MODELING NITROGEN CYCLING AND
EXPORT IN FORESTED WATERSHEDS
USING HSPF
"AQUA TERRA
'ElMViRONMENTAl ASSESSMENT
CONSULTANTS
V/ATER RESOURCES-
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USGS/EPA
September 1996
MODELING NITROGEN CYCLING AND
EXPORT IN FORESTED WATERSHEDS
USING HSPF
by
B. R. Bicknell, A. S. Donigian, Jr.
T. H. Jobes, R. V. Chinnaswamy
AQUA TERRA Consultants
Mountain View, CA 94043
USGS Contract No. 14-08-0001-23472
Delivery Orders No. 17 and No. 25
Technical Project Officers
Alan M. Lumb
Hydrologic Analysis Support Section
U.S. Geological Survey, WRD, Reston, VA 20192
Thomas O. Barnwell
U.S. Environmental Protection Agency
National Exposure Research Laboratory
Ecosystems Research Division, Athens, GA 30605-2700
OFFICE OF RESEARCH AND DEVELOPMENT
NATIONAL EXPOSURE RESEARCH LABORATORY
U.S. ENVIRONMENTAL PROTECTION AGENCY
ATHENS, GA 30605-2700
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DISCLAIMER
The work presented in this document has been funded by the U.S. Geological Survey under
Contract No. 14-08-0001-23472 to AQUA TERRA Consultants. It has not been subjected to
the Survey's peer and administrative review and has not been approved as a USGS document.
Mention of trade names or commercial products does not constitute endorsement or
recommendation for use.
11
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ABSTRACT
The Chesapeake Bay Watershed Model provides nutrient loadings to the Chesapeake Bay Water
Quality Model for use in estimating the impacts of land use and potential management options
on water quality in the Bay. The nonpoint loadings are defined by the various land use
categories in the Watershed Model which include forests, agricultural cropland (conventional and
conservation tillage), pasture, haylands, urban, and animal waste areas. The U.S. EPA
Hydrologic Simulation Program-FORTRAN (HSPF) is the framework for the Watershed Model,
and the AGCHEM module within HSPF is used to model nutrient cycling and export for the
agricultural croplands and haylands. A recent review of the nitrogen loadings calculated by the
Watershed Model indicates an over-prediction of nitrogen loadings from forested segments of
the drainage area. Furthermore, this review, performed by Oak Ridge National Laboratory
(ORNL) and sponsored by the U.S. EPA Athens Laboratory, concluded that the HSPF
AGCHEM module provided a sound basis for selected enhancements that would improve
simulation of nitrogen cycling and export in forested systems.
In this effort, based on the recommendations provided in the ORNL review, the HSPF
AGCHEM module was modified to provide a more detailed representation of specific nitrogen
cycling processes which are important in forested systems. These changes included: (1)
expanding the single organic N compartment to allow both particulate and dissolved fractions
of both labile and refractory organic N (i.e. four compartments); (2) providing both below-
ground and above-ground plant N compartments; (3) allowing the return (i.e. cycling) of above-
ground plant N to the soil N through an intermediate litter N compartment; (4) allowing return
of below-ground plant N to the soil organic N; and (5) providing options to use saturation
kinetics (i.e. Michaelis-Menton) for immobilization and plant N uptake. In addition, in
conjunction with changes implemented to improve N modeling in agricultural areas,
volatilization of soil ammonia and soil N fixation by leguminous plants were included as
additional options.
The modified AGCHEM module was applied at a regional scale for selected segments of the
CBP Watershed model, and then for small forested sites within these model segments where
observed data had been collected by the U.S. Geological Survey. This report describes the code
and algorithm enhancements, the estimation of expected N balances and export for forests to
help guide the calibration effort, and the results of testing at both the regional and small
watershed sites. Recommendations are provided for further testing and improvement of the N
cycle representation for forests.
111
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This report was submitted in fulfillment of Contract No. 14-08-0001-23472, Delivery Orders
No. 17 and No. 25, by AQUA TERRA Consultants of Mountain View, CA under sponsorship
of the U.S. Geological Survey. This report covers the period from December 1993 through
September 1996, and work was completed as of 27 September 1996.
IV
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CONTENTS
Page
Disclaimer ii
Abstract iii
Figures vii
Tables ix
Acknowledgments x
1.0 INTRODUCTION 1
1.1 Study Goals and Objectives 1
' 1.2 Overview of HSPF Model, AGCHEN Module, and Study Sites 2
1.3 Study Conclusions and Recommendations 3
1.4 Format of Report 8
2.0 REFINEMENTS TO AGCHEM MODULE FOR FORESTED WATERSHEDS . . 9
2.1 Overview 9
2.2 HSPF AGCHEM Nitrogen Modeling Framework 10
2.3 Forest N Process Enhancements 11
3.0 REGIONAL-SCALE TESTING ON SHENANDOAH RIVER WATERSHED
MODEL SEGMENTS 22
3.1 Testing Objectives, Site, and Procedures 22
3.2 Expected Forest N Balance and Storages 23
3.3 AGCHEM Forest N Testing Results 25
3.4 Conclusions and Recommendations 42
4.0 SMALL WATERSHED SITE TESTING OF FOREST N MODELING 44
4.1 Testing Overview 44
4.2 Test Site Locations, Parameterization and Database 44
4.3 Hydrologic Calibration 54
4.4 AGCHEM Testing for Forest N cycling and Export 62
5.0 REFERENCES 82
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APPENDICES 85
Appendix A. Hunting Creek Hydrology Simulation Results 86
Appendix B. Young Womans Creek Hydrology Simulation Results 92
Appendix C. Shenandoah Segment 190 UCI 98
Appendix D. Hunting Creek UCI 108
Appendix E. Young Womans Creek UCI 127
VI
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FIGURES
1.1 HSPF PERLND Structure Chart 4
1.2 Nitrogen and Phosphorus Transformations in AGCHEM,
HSPF Version No. 10 5
1.3 Chesapeake Bay Watershed Model Segments and Locations of Test Sites .... 6
2.1 Modified AGCHEM Module for Forest N Transformation '..... 12
3.1 Frequency Analysis of Flow at Reach 190, South Fork Shenandoah River
at Front Royal, VA 30
3.2 Simulated Forest AG, BG, Litter, and Total Plant N in Shenandoah Segment 190 35
3.3 Simulated Forest Aboveground and Belowground Plant N in
Shenandoah Segment 190 36
3.4 Simulated Labile, Refractory, Total Plant N, and Total N Storage
in Shenandoah Segment 190 37
3.5 Simulated Forest Monthly Mineralization Rate in Shenandoah Segment 190 ... 39
3.6 Simulated Monthly NO3-N, Organic N, and NH3-N Concentrations from Forests
in Shenandoah Segment 190 41
4.1 Hunting Creek Watershed and Monitoring Stations 46
4.2 Young Womans Creek Watershed and Location of Meteorologic Stations .... 51
4.3 Simulated and Observed Flow for Hunting Creek Tributary
near Foxville, MD, 1990-91 56
4.4 Flow Frequency Simulation for Hunting Creek Tributary near Foxville, MD . . 57
4.5 Simulated and Observed Flow for Young Womans Creek
near Renovo, PA, 1988-89 60
4.6 Flow Frequency Simulation for Young Womans Creek near Renovo, PA .... 61
4.7 Simulated Forest AG, BG, Litter, and Total Plant N in Hunting Creek Watershed 73
4.8 Simulated Forest Aboveground and Belowground Plant N in Hunting Creek
Watershed, 1984-85 74
4.9 Simulated Labile, Refractory, Total Plant N, and Total N Storage
in Hunting Creek Watershed 75
4.10 Simulated Monthly NO3-N, Organic N, and NH3-N Concentrations
in Hunting Creek Watershed Compared to Observed Data 76
4.11 Simulated Forest AG, BG, Litter, and Total Plant N in Young Womans Creek
Watershed 77
4.12 Simulated Forest Aboveground and Belowground Plant N in
Young Womans Creek Watershed, 1984-85 78
vii
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4.13 Simulated Labile, Refractory, Total Plant N, and Total N Storage
in Young Womans Creek Watershed 79
4.14 Simulated Monthly NO3-N, Organic N, and NH3-N Concentrations in
Young Womans Creek Watershed Compared to Observed Data 80
4.15 Simulated Forest Monthly Mineralization Rate for Hunting Creek and
Young Womans Creek Watersheds 81
Vlll
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TABLES
Page
3.1 Targets for Forest Nitrogen Balance and Storages 24
3.2 Typical Nitrogen Balance For Major Crops and Land Use/Land Cover
Categories (Ib/ac/yr) 26
3.3 Simulated Hydrologic Balance for Forest Land in Shenandoah
Model Segment 190 28
3.4 Shenandoah River Watershed Hydrologic Calibration: Comparison of Annual
Total Observed vs Simulated Flow for South Fork Shenandoah River
at Front Royal, VA 28
3.5 AGCHEM Simulation Results for Forest Land in Shenandoah
Model Segment 190 31
3.6 Simulated Changes in Forest N Pools from 1984 to 1991 for
the Shenandoah Segment 34
4.1 Meteorologic, Streamflow and Water Quality Data for Simulation of Hunting
Creek Tributary near Foxville, MD 47
4.2 Meteorologic, Streamflow and Water Quality Data for Simulation of Young
Womans Creek, PA 50
4.3 Comparison of Annual Total Observed Flow vs Simulated Flow:
Hunting Creek Tributary near Foxville, MD (USGS Gage No. 01640970) .... 55
4.4 Simulated Hydrologic Balance for Hunting Creek Watershed 55
4.5 Comparison of Annual Total Observed Flow vs Simulated Flow:
Young Womans Creek near Renovo, PA (USGS Gage No. 01545600) 59
4.6 Simulated Hydrologic Balance for Young Womans Creek Watershed 59
4.7 AGCHEM Simulation Results for Forest Land in Hunting Creek Watershed ... 66
4.8 AGCHEM Simulation Results for Forest Land in Young
Womans Creek Watershed 69
4.9 Simulated Changes in Forest N Pools from 1984 to 1991 for Hunting Creek . . 72
4.10 Simulated Changes in Forest N Pools from 1984 to 1991 for Young
Womans Creek 72
IX
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ACKNOWLEDGMENTS
This report was prepared under Delivery Orders No. 17 and 25 of Contract No. 14-08-0001-
23472 by AQUA TERRA Consultants for the U.S. Geological Survey, Hydrologic Analysis and
Support Section of the Office of Surface Water in Reston, VA. Original sponsorship of the
study was provided through the High Performance Computing and Communications Program
(HPCCP) by the U.S. Environmental Protection Agency, National Exposure Research
Laboratory, Ecosystem Research Division in Athens, GA. The Technical Project Officers for
this work were Dr. Alan Lumb, with the U.S.G.S. in Reston, VA and Mr. Thomas Barnwell
of the EPA, Athens, GA. Both of these individuals were instrumental in the successful conduct
and completion of this work, and their contributions are gratefully acknowledged.
A number of individuals provided data and information vital to the performance of this study.
Drs. Carolyn Hunsaker, Charles Garten, and Patrick Mulholland of Oak Ridge National
Laboratory, Oak Ridge TN performed the basic algorithm research and development which was
the foundation for the code changes in HSPF implemented to better represent nitrogen cycling
in forested systems. They willingly answered our questions and graciously responded to our
requests throughout the study. Their participation was a critical element of this work.
Data for site testing was provided by various U.S.G.S. offices and staff. Dr. Karen Rice of the
Charlottesville, VA office, Mr. Joseph Bachman and Mr. George Zynjuk of the Towson, MD
office, and Mr. Lloyd Reed of the Harrisburg, PA office provided data and responded to our
numerous questions and requests for information. In addition Mr. Zynjuk and Mr. Reed were
our gracious guides for field visits to the small watershed sites in MD and PA. We would like
to express our appreciation for all the assistance provided by these individuals.
For AQUA TERRA Consultants, Mr. Brian Bicknell and Mr. Anthony Donigian served as
Project Managers for different aspects of the study. Mr. Bicknell designed the code
enhancements to AGCHEM, and directed Mr. Tom Jobes in the code implementation and
testing. Mr. Donigian reviewed the code design, provided technical direction in the development
of the expected N balance, and led the regional and small site testing effort; he was assisted by
Mr. Radha Chinnaswamy who performed the database development, reviewed the nitrogen
literature, and performed the model runs for both hydrologic calibration and forest nitrogen
simulations. Mr. Donigian and Mr. Bicknell wrote the final report with assistance from Mr.
Chinnaswamy and Mr. Jobes.
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SECTION 1.0
INTRODUCTION
1.1 STUDY GOALS AND OBJECTIVES
The Chesapeake Bay Watershed Model (Linker et al. 1993) provides nutrient loadings to the
Chesapeake Bay Water Quality Model for use in estimating the impacts of land use and other
management scenarios on water quality in the Bay. The nonpoint loadings are defined by the
various land use categories in the Watershed Model, which include forests, cropland, pasture,
haylands, urban, and animal waste areas. The U.S. EPA Hydrologic Simulation Program-
FORTRAN (HSPF) (Bicknell et al. 1993) provides the framework for the Watershed Model, and
the AGCHEM module within HSPF is used to model nutrient cycling and export for the
agricultural croplands and haylands.
A recent review of the nitrogen loadings calculated by the Watershed Model indicates an over-
prediction of nitrogen loadings from forested segments of the model. Under a joint USGS/EPA
effort to improve AGCHEM for representing nitrogen mass-balance modeling for forest areas
at the watershed scale, a number of refinements have been implemented and are being tested
based on recommendations by Oak Ridge National Laboratory (Hunsaker et al. 1994).
In this effort, based on the recommendations provided in the ORNL review, the HSPF
AGCHEM module was modified to provide a more detailed representation of specific nitrogen
cycling processes which are important in forested systems. These changes included: (1)
expanding the single organic N compartment to allow both particulate and dissolved fractions
of both labile and refractory organic N (i.e. four compartments); (2) providing both below-
ground and above-ground plant N compartments; (3) allowing the return (i.e. cycling) of above-
ground plant N to the soil N through an intermediate litter N compartment; (4) allowing return
of below-ground plant N to the soil organic N; and (5) providing options to use saturation
kinetics (i.e. Michaelis-Menton) for immobilization and plant N uptake. In addition, in
conjunction with changes implemented to improve N modeling in agricultural areas,
volatilization of soil ammonia and soil N fixation by leguminous plants were included as
additional options.
The modified AGCHEM module was applied at a regional scale for selected segments of the
CBP Watershed model, and then for small forested sites within these model segments where
observed data had been collected by the U.S. Geological Survey. This report describes the code
and algorithm enhancements, the estimation of expected N balances and export for forests to
1
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help guide the calibration effort, and the results of testing at both the regional and small
watershed sites. Recommendations are provided for further testing and improvement of the N
cycle representation for forests.
1.2 OVERVIEW OF HSPF MODEL, AGCHEM MODULE, AND STUDY SITES
The Hydrological Simulation Program - FORTRAN (HSPF) (Johanson et al., 1984; Bicknell et
al., 1993) is a comprehensive package for simulation of watershed hydrology and water quality
for both conventional and toxic organic pollutants. HSPF incorporates the watershed scale ARM
and NFS models into a basin-scale analysis framework that includes fate and transport in one-
dimensional stream channels. It is the only comprehensive model of watershed hydrology and
water quality that allows the integrated simulation of land and soil contaminant runoff processes
with instream hydraulic, water temperature, sediment transport, nutrient, and sediment-chemical
interactions. The runoff quality capabilities include both simple relationships (i.e., empirical,
buildup/washoff, constant concentrations) and detailed soil process options (i.e., leaching,
sorption, soil attenuation, and soil nutrient transformations).
HSPF contains three application modules and six utility modules. The three application modules
simulate the hydrologic/hydraulic and water quality components of the watershed. The utility
modules are used to manipulate and analyze time-series data. The three application modules
within HSPF, and their primary functions, are as follows:
(1) PERLND - Simulates runoff and water quality constituents from pervious land areas
in the watershed.
(2) IMPLND - Simulates impervious land area runoff and water quality.
(3) RCHRES - Simulates the movement of runoff water and its associated water quality
constituents in stream channels and mixed reservoirs.
As PERLND simulates the water quality and quantity processes that occur on pervious land
areas, it is the most frequently used part of HSPF. To simulate these processes, PERLND
models the movement of water along three paths: overland flow, interflow, and groundwater
flow. Each of these three paths experiences differences in time delay and differences in
interactions between water and its various dissolved constituents. A variety of storage zones are
used to represent the processes which occur on the land surface and in the soil horizons. Snow
accumulation and melt are also included in the PERLND module so that the complete range of
physical processes affecting the generation of water and associated water quality constituents can
be represented. Some of the many capabilities available in the PERLND module include the
simulation of:
water budget and runoff components
snow accumulation and melt
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sediment production and removal
nitrogen and phosphorus fate and runoff
pesticide fate and runoff
movement of a tracer chemical
Figure 1.1 defines the structure and contents of the PERLND module. The module features
individual compartments for modeling air temperature as a function of elevation (ATEMP), snow
accumulation and melting (SNOW), hydrologic water budget (PWATER), sediment production
and removal (SEDMNT), soil temperature (PSTEMP), surface runoff water temperature and gas
concentrations (PWTGAS), generalized water quality constituents (PQUAL), solute transport
(MSTLAY), pesticides (PEST), nitrogen (NITR), phosphorus (PHOS), and conservatives
(TRACER).
The AGCHEM module (or subroutines) are shown within the dashed lines encompassing the
MSTLAY, PEST, NITR, PHOS, and TRACER subroutines. Plant uptake of soil nutrients is
performed within the NITR and PHOS modules, whose transformation diagrams are shown in
Figure 1.2. Plant uptake, and all other biochemical transformations in Figure 1.2, are
represented (in HSPF Version No. 10) as first-order rate processes with an Arrhenius
temperature correction adjustment based on simulated soil temperatures. The first-order plant
uptake rates are defined by the user, can be specified separately for each soil zone (i.e. surface,
upper, lower, groundwater) within HSPF, and can vary for each month to approximate the
monthly pattern of crop growth and nutrient uptake. The rates are adjusted during calibration
to mimic the expected annual nutrient uptake and the seasonal pattern for the specific crop.
As noted above, the AGCHEM module, as modified in this effort to enhance the ability to model
N cycling in forests, was applied at both a regional scale for a selected segment of the CBP
Watershed Model, and then for small forested sites where observed data had been collected by
the U.S. Geological Survey. Figure 1.3 shows the locations of the test sites along with the
segmentation scheme for the Watershed Model for the Above Fall Line (AFL) portion of the
Chesapeake Bay Watershed. The 'regional' scale application and testing of the forest N cycling
enhancements were performed on the Shenandoah River watershed segments (No. 190 and No.
200, in Figure 1.3), while the small forested test sites included Hunting Creek near Foxville,
MD (within Segment 750) and Young Woman's Creek near Renovo, PA (within Segment 60).
1.3 STUDY CONCLUSIONS AND RECOMMENDATIONS
The ORNL Study (Hunsaker et al., 1994) concluded that the AGCHEM module of HSPF
provided a sound scientific framework for modeling N cycling in forested systems at the regional
scale needed by the Chesapeake Bay Program for determining the N export and contributions
by forests to the Chesapeake Bay. Their recommendations were the basis for enhancements to
the AGCHEM module that were subsequently evaluated and tested at both the regional and small
site scale in this study. The following conclusions and recommendations were derived from
these testing results:
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PERLND Structure Chart
PERLND
Simulate
a pervious
land
segment
MST
ATEMP 1
Correct air
tempera-
ture
SNOW 1
Simulate
snow and
Ice
P WATER 1
Simulate
water
budget
SEDMNT!
Simulate
sediment
PSTEMP 1 PWTGASl PQUAL 1
Estimate
soil
tempera-
ture(s)
Estimate
water
tempera-
ture
gas
and
con-
centrations
Simulate
general
quail
ty
constit-
uents
LAY 1
Estimate
solute
transport
PEST
1 NITR
Simulate
pesticides
1 PHOS
Simulate
nitrogen
1 TRACER 1
Simulate
phosphorus
AGRI-CHEMICAL SECTIONS -
Simulate
a tracer
(conserva-
tive)
Figure 1.1 HSPF PERLND Structure Chart
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Nutrient Transformations Simulated by the AGCHEM Module
N2
PLNT-N
KDNI
KPLN
NO3
(+NO2)
KADAM
NH4 - A
KNI
NH4 - S
Key
KDSA
KAM
N-Nltrogen
P-Phoaphorua
A-Adaorbed
S-Solutlon
K-Reactlon Rate
Parameters
KIMAM
ORG - N
KIMNI
A. Nitrogen transformations In NITR module
PLNT -P
KDSP
PO4 -A
KPLP KIMP
PO4 -S
ORG - P
KADP KMP
B. Phosphorus transformations In PHO8 module
Figure 1.2 Nitrogen and Phosphorus Transformations in AGCHEM,
HSPF Version No. 10
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Young Womans
Creek, PA
Shenandoah
Model Segments
Hunting Creek, MD
Figure 1.3 Chesapeake Bay Watershed Model Segments and Location of Test Sites
6
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a. The enhancements to the AGCHEM module of HSPF for simulating N cycling in
forested systems have provided a reasonable representation of both the N export, internal
cycling, and various N pools, or storages expected for the forested ecosystems.
Application at both a large, regional scale and small monitored watersheds has been
hampered by limited relevant data for both parameterization and calibration. However,
the expected export of the various N forms, and the overall N balance and pools, are
within expected ranges, and the mass-balance framework provides a sound basis for
nutrient management issues within the Chesapeake Bay Watershed.
b. The modeling showed that for forested systems with atmospheric deposition as the
primary external input (i.e. no fertilization and little N fixation) and watershed export as
the primary loss (i.e. no denitrification or leaching), the net annual impact or change in
the Total N of the ecosystem was essentially equal to the difference in these two fluxes,
i.e. atmospheric deposition minus N export. Closing this simple mass balance, after all
the internal fluxes and transformations, confirmed the functioning of the code changes
and, with relatively low N export, identified our test sites as being in the very early
stages (i.e. Stage 0 or 1) of N saturation.
c. Plant uptake of N by forests is a key component of the cycling process. However, the
seasonal uptake pattern produced in this study appeared to be more linear with time than
the expected s-shaped pattern showing the largest uptake fluxes during leaf-out in early
spring and summer. Further calibration and/or investigation of alternative options within
AGCHEM (e.g. first-order rates, yield-based) should be pursued to improve the N uptake
timing during the year. This may also help refine the seasonal pattern of the export of
both nitrate and ammonia.
d. Because there are wide ranges in the magnitudes of N storages in the various plant and
soil pools, depending on soil conditions, climate, stand age, tree species, etc., more
detailed information is needed for these state variables for valid application of the model
to both specific regional and small-site scales. Future testing should focus on sites with
more comprehensive data on the forest N pools and N export.
e. The AGCHEM enhancements for representation of soil organics expanded the single
particulate organic N pool into four separate pools for dissolved and particulate forms
of both labile and refractory organic N. This helped to allow export of dissolved organic
N (DON) which is a significant component of the total N export from forested areas.
The DON export values produced by the model are reasonable and within expected
ranges, but the soil storages need further investigation. Our simulations showed labile
N continually decreasing during the simulation period due to the expected range of
mineralization fluxes or lack of sufficient immobilization and plant return to the labile
pool. More calibration, soil organic data, and process investigation is needed to better
define the fractionation into the various organic N pools, partitioning between the
dissolved and particulate forms, conversion mechanisms between the labile and refractory
forms, and appropriate changes in storages with time in forested ecosystems.
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f. The aboveground (AG), belowground (BG), and plant litter N pools included in the new
AGCHEM module provide a more realistic approach to N uptake and subsequent
disposition of plant material and residues, and their impact on soil N levels. Our
simulations produced realistic patterns of seasonal changes in these pools; however, more
data is needed to validate and better define the plant return pathways through the litter
compartment and from the BG pool to the soil.
g. Further model testing work is recommended to pursue the issues described above. These
testing efforts should focus on watershed sites where observed data is available for more
complete model parameterization and calibration of storages (plant, litter and soil),
important fluxes (i.e. mineralization, immobilization, plant uptake and return), and export
of all N forms, including both inorganic and organic N. The most appropriate sites
would include the type of pool and flux data collected at the Integrated Forest Study
(IPS) sites (Johnson and Lindberg, 1992), in combination with meteorologic and
hydrologic monitoring to provide the complete database needed to determine N export
and support watershed modeling. Potential sites with these characteristics that should be
considered include the IPS sites at the Coweeta Hydrologic Laboratory, NC; the Walker
Branch Watershed, Oak Ridge, TN (Johnson and Van Hook, 1989); the well-known
Hubbard Brook watershed, NH; and other IPS sites where detailed meteorologic and
hydrologic monitoring is performed.
1.4 FORMAT OF THIS REPORT
Following this introduction, Section 2 describes the refinements of the AGCHEM module for
modeling N cycling in forested watersheds, while Chapter 3 presents the results of testing
performed on a regional scale on the Shenandoah model segments. The testing and application
effort involved identifying target, or expected, components of the N balance in forested systems,
and the general magnitude of these components as a guide to the calibration process; the
development of the expected N balance is also discussed in Section 3. In Section 4, we conclude
with the small watershed site testing results for both the Hunting Creek, MD and Young
Womans Creek, PA watersheds. The Appendices include complete hydrologic simulation results
for each test subbasin and the HSPF input (i.e. Users Control Input, or UCI) including
parameter values and simulated options for each site.
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SECTION 2.0
REFINEMENTS TO AGCHEM MODULE FOR
FORESTED WATERSHEDS
2.1 OVERVIEW
The primary nitrogen inputs to forests are atmospheric deposition and nitrogen fixation, and the
primary losses are leaching and denitrification. Important processes are retention of ammonium
by the soil, mineralization of organic N, and uptake of available nitrogen by plants. Typically,
forests are deficient in nitrogen, and consequently, they tend to retain input nitrogen. However,
after long term nitrogen inputs, forests can eventually become saturated, at which point the
combined effective inputs of mineralization and atmospheric deposition may exceed the capacity
of the plants to take up the available nitrogen. At this point, nitrogen exports, particularly
nitrate, begin to increase. The needs of the forest nitrogen model for the Chesapeake Bay are
representation of the principal state variables already considered in the Watershed Model,
representation of the important variables and processes in forests, responsiveness to atmospheric
deposition, and ability to generate the expected magnitude and timing of nitrogen exports.
Under this joint USGS/EPA effort to improve watershed modeling capabilities for representing
N mass-balance modeling for forested areas at the both the regional and watershed scale, Oak
Ridge National Laboratory (ORNL) reviewed the available literature on forest N export, cycling,
and modeling with a specific focus on the capabilities needed within the Chesapeake Bay
Watershed Model (Hunsaker et al., 1994). They concluded that the AGCHEM module within
HSPF provided a sound scientific framework for modeling N cycling and export in forests at a
regional scale, but that additional N process representations and enhancements were needed to
better represent conditions and processes specific to forested systems. Based primarily on their
specific recommendations for forest-related modifications to AGCHEM, we implemented the
following changes:
The particulate organic nitrogen state variable was subdivided into four soil organic
nitrogen state variables: labile particulate, labile solution, refractory particulate, and
refractory solution. The particulate labile fraction is assumed to convert to the refractory
form using first-order kinetics, and both particulate species are assumed to leach to the
solution forms using a simple partitioning function.
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Because uptake of inorganic nitrogen from forest soil can be saturated at high nitrogen
concentrations, an optional method was added for modeling nitrogen uptake and
immobilization, using saturation kinetics instead of first-order kinetics.
The plant nitrogen state variable was subdivided into aboveground and belowground
compartments.
A litter nitrogen compartment was added to provide an intermediate compartment
between the aboveground plant nitrogen and the surface and upper layer organic nitrogen.
New pathways were added to allow plant nitrogen in the aboveground and belowground
compartments to return to the litter and organic nitrogen in the soil using first-order
kinetics.
Concurrently, additional modifications were made to the AGCHEM module to improve specific
nitrogen process modeling for agricultural areas. Ammonia volatilization was added for
conditions where animal waste or fertilizer applications warrant this mechanism; soil N fixation
by leguminous plants was added; and a yield-based plant uptake option was included to make
the model more sensitive to nutrient applications (Donigian et al., 1995). HSPF Version No.
11 (Bicknell et al., 1996) includes all these additional algorithm refinements plus those
recommended for forested conditions. In this section we first describe the AGCHEM framework
for N modeling, followed by the forest N enhancements and the current N process descriptions
of the AGCHEM module; a more complete description of processes, parameters, and format
requirements are in the HSPF User Manual (Bicknell et al., 1996). Many of the process
descriptions are extracted directly from the manual, so readers may need to refer to it for
parameter designations and other clarifications.
2.2 HSPF AGCHEM NITROGEN MODELING FRAMEWORK
The AGCHEM modules of HSPF (Bicknell et al., 1993) attempt to represent the major nitrogen
and phosphorus processes occurring within the soil profile that determine and control the fluxes
of soil nutrients within the soil/plant/terrestrial environment. The model maintains soil nutrient
storages, allows for various nutrient application modes, and simulates the nutrient balance and
subsequent movement of soil nutrients based on runoff, soil moisture, and sediment values
calculated by the corresponding sections of HSPF. These fluxes and state variables are used by
the AGCHEM module to provide the moisture storage and transport values needed for the
simulation of nutrient transformation and transport. Fertilizers, animal wastes, plant residues,
and other nutrient inputs (e.g., atmospheric deposition, sludge application) are applied in their
elemental chemical form (i.e., NH4-N, NO3-N, PO4-P, Organic N, Organic P) either as a surface
application or incorporated into the soil.
Nutrients are stored in four depth layers: surface zone, upper zone, lower zone, and groundwater
zone. The depths of each zone are defined by input parameters estimated by the model user.
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The shallow surface layer is a continuous mixing zone which may be defined functionally as the
zone of interaction of surface applied chemicals, from which surface runoff, sediment erosion,
and associated chemicals are transported to a waterbody. The upper zone extends from the
bottom of the surface zone to a depth often ranging from 10 to 20 cm, and usually corresponds
to the depth of major tillage operations and/or incorporation of applied nutrients. The lower
zone is the primary source of plant evaporation, and it regulates the amount of soluble chemicals
that can be introduced into groundwater since the chemicals must pass through this layer. For
agricultural applications, the lower zone depth is typically set to the maximum depth of the crop
root zone, usually ranging from 50 to 150 cm. The groundwater layer represents the depth of
shallow groundwater that actively contributes baseflow to the stream channel. It can also be
visualized as a shallow mixing depth within the surface aquifer that controls the chemical
transformations and associated contributions to baseflow concentrations.
2.3 FOREST N PROCESS ENHANCEMENTS
Within the AGCHEM module, the NITR section performs the reactions and transformations of
nitrogen species within the soil profile as a basis for predicting the soil nitrogen storages and
resulting nitrogen content of runoff, both surface and subsurface. The N transformations,
nutrient storages, and reaction rates considered by NITR, as modified in these recent
development efforts, are shown in Figure 2.1. Each of the subsurface processes and
compartments (i.e., not aboveground plant N, litter N, or related processes) occur in each of the
four soil layers modeled in the AGCHEM module. The nutrient simulation primarily assumes
first-order reaction rates, but the recent modifications have added additional options and
capabilities to improve the plant uptake representation, forest litter, and return of plant N to the
soil. In the original version, the processes simulated include immobilization, mineralization,
nitrification/denitrification, plant uptake, and adsorption/desorption (for which an equilibrium
isotherm option is available). As noted above, the recent modifications are summarized as
follows:
The particulate organic N state variable was divided into four state variables: labile
particulate, labile solution, refractory particulate, and refractory solution.
An optional method was added for modeling nitrogen uptake and immobilization, using
saturation kinetics instead of first-order kinetics.
The plant N state variable was divided into Aboveground and Belowground compartments.
A new pathway was added for plant N to "return" to organic N in the soil.
A litter N compartment was added to provide an intermediate compartment between the
Aboveground plant N and the surface and upper layer organic N.
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N Fixation
Denitrification
Atmospheric
Deposition
Volatilization
Atmospheric
Deposition
Uptake of N03 and NH4
Litterfall
Plant N return
Conversion
Atmospheric
Deposition
* return of above ground plant N and litter N
occurs to surface and upper zones only
Figure 2.1 Modified AGCHEM Module for Forest N Transformations
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A yield-based plant uptake option was included as an alternative to the first-order rates,
and allow for multiple cropping, nitrogen fixation, and nutrient/moisture stress
conditions.
Ammonia volatilization was added for conditions where animal waste or fertilizer
applications warrant this loss mechanism.
2.3.1 Soil Nitrogen Storages and Transformations
The diagram in Figure 2.1 shows the N transformation pathways, processes, and N storages or
pools maintained in the enhanced AGCHEM model. Reaction rates are input on a per day basis
for each soil layer. Nitrite (N02) transforms so quickly in most soils that it is not considered
separately. The adsorbed phase represents the nutrients in a complex form along with those
adsorbed on the soil. Selected plant uptake parameters are input monthly as a function of the
stage of crop growth and expected yields. These monthly parameters are adjusted to represent
the crop uptake of N from the soil storages and to distribute it throughout the growing season.
The nitrogen species of nitrate, ammonia, and four forms of organic nitrogen (i.e. particulate
organic nitrogen (labile and refractory) and dissolved organic nitrogen (labile and refractory))
are represented. The soil nitrogen transformations include plant uptake of nitrate and
ammonium, return of plant nitrogen to organic nitrogen, denitrification or reduction of
nitrate-nitrite, immobilization of nitrate-nitrite and ammonium, mineralization of organic
nitrogen, fixation of atmospheric nitrogen, volatilization of ammonium, and the
adsorption/desorption of ammonium and the organic forms. All reactions and fluxes are
computed on a daily basis and then the storages are updated.
Nitrogen reactions can be divided between those that are chemical in nature and those that are
a combination of chemical and biological reactions. The adsorption and desorption of
ammonium is a chemical process. The user has the option of simulating ammonium adsorption
and desorption by first order kinetics with subroutine FIRORD or by the Freundlich isotherm
method with subroutine SV (discussed below).
The other reactions are a combination of biological and chemical transformations. They all can
be accomplished by first order kinetics, but plant uptake can optionally use alternative algorithms
(described below). The optimum first order kinetic rate parameter is corrected for soil
temperatures below 35 degrees C by the generalized equation:
KK = K*TH**(TMP-35.0)
where:
KK = temperature corrected first order transformation rate (per day)
K = optimum first order reaction rate parameter (per day)
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TH = temperature coefficient for reaction rate correction (-)
(typically about 1.06)
TMP = soil layer temperature (degrees C)
Soil temperature must be simulated, or input by the user, when nitrogen processes are being
simulated with AGCHEM. When temperatures are greater than 35 degrees C, the rate is
considered optimum, that is, KK is set equal to K. When the temperature of the soil layer is
below 4 degrees C or the layer is dry, no biochemical transformations occur. Identifiers with
a leading "K" (e.g., KDNI) are the optimum rates; those for corrected rates have both a leading
and trailing "K" (e.g., KDNIK). The corrected reaction rate parameters are determined every
day and multiplied by the respective storages as shown in Figure 2.1 to obtain the reaction
fluxes.
The biochemical reaction rate fluxes that are shown in Figure 2.1 are coupled, that is, added to
and subtracted from the storages simultaneously. The coupling of the fluxes is efficient in use
of computer time but has a tendency to produce unrealistic negative storages when large reaction
intervals and large reaction rates are used jointly. A method has been introduced which will
modify the reaction fluxes so that they do not produce negative storages. A warning message
is issued when this modification occurs.
Ammonia Volatilization
Ammonia volatilization is included as an optional (AMVOFG = 1) first-order reaction in order
to allow large concentrations of ammonia in the soil, resulting from animal waste and fertilizer
applications, to be attenuated by losses to the atmosphere. The original formulation by Reddy
et al., (1979) included adjustment for variable soil cation exchange capacity (CEC) and wind
speed, and it could be "turned off" after seven days. In HSPF, it is assumed that: (1) the CEC
factor can be incorporated into the first-order rate constant by the user, and (2) the wind (air
flow) is always high enough to result in maximum loss; Reddy's original method reduced the
volatilization rate only when wind speed was less than 1.4 km/day. Downward adjustment of
the rate, after an initial period of high losses, requires use of the Special Actions capability.
The volatilization flux in each layer is computed as:
AMVOL = AMSU * KVOL * TCVOL**(TEMP-TRFVOL)
where:
AMVOL = loss of ammonia (mg/l/day)
AMSU = dissolved ammonia concentration (mg/1)
KVOL = rate constant at 20 C (/day)
TCVOL = temperature correction coefficient (-)
TEMP = air temperature (C)
TRFVOL = reference temperature for KVOL (C)
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The temperature correction for volatilization of ammonia is slightly different than the standard
method used for the other reactions. The reference temperature is user-specified, instead of 35
degrees C, since rates in the literature are often given at a temperature of 20 degrees C. Also,
instead of attaining a maximum value at the reference temperature, the volatilization rate is
adjusted upwards when the soil temperature exceeds the reference temperature.
Sorption/Desorption of Ammonium
When FORAFG = 0, the ammonium adsorption and desorption reaction fluxes of chemicals are
simulated with the FIRORD subroutine using temperature dependent first-order kinetics. The
calculation of the reaction fluxes by first-order kinetics for soil temperatures less than 35 degrees
C takes the form:
DES = CMAD*KDS*THKDS**(TMP-35.0)
ADS = CMSU*KAD*THKAD**(TMP-35.0)
where:
DES = current desorption flux of chemical (mass/area per interval)
CMAD = storage of adsorbed chemical (mass/area)
KDS = first-order desorption rate parameter (per interval)
THKDS = temperature correction parameter for desorption
TMP = soil layer temperature (degrees C)
ADS = current adsorption flux of chemical (mass/area per interval)
CMSU = storage of chemical in solution (mass/area)
KAD = first-order adsorption rate parameter (per interval)
THKAD = temperature correction parameter for adsorption
(THKDS and THKAD are typically about 1.06 )
All of the variables except the temperature coefficients may vary with the layer of the soil being
simulated. As noted above, soil temperature must be simulated when nitrogen is being
simulated. The temperature correction of the reaction rate parameter is based on the Arrhenius
equation. At temperatures of 35 degrees C or above no correction is made. When the
temperature is at 0 degrees C or below or the soil layer is dry, no adsorption and desorption
occurs.
When FORAFG = 1, the SV subroutine simulates sorption/desorption based on the Freundlich
isotherm, which, unlike first-order kinetics, assumes instantaneous equilibrium. That is, no
matter how much chemical is added to a particular phase, equilibrium is assumed to be
established between the solution and adsorbed phase of the chemical. These methods also
assume that for any given amount of chemical in the soil, the equilibrium distribution of the
chemical between the soil solution and on the soil particle can be found from an isotherm.
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The adsorbed and solution phases of ammonium are determined in this subroutine by a
modification of the standard Freundlich equation (shown below). When the amount of chemical
is less than the capacity of the soil particle lattice to permanently bind the chemical (XFIX), then
all the material is consider fixed. All the fixed chemical is contained in the adsorbed phase of
the soil layer storage. Otherwise, the Freundlich equation for curve 1 is used to determine the
partitioning of the chemical into the adsorbed and solution phases:
X = KF1*C**(1/N1) + XFIX
where:
X = chemical adsorbed on soil (ppm of soil)
KF1 = single value Freundlich K coefficient
C = equilibrium chemical concentration in solution (ppm of solution)
Nl = single value Freundlich exponent
XFIX = chemical which is permanently fixed (ppm of soil)
The above equation is solved in subroutine ITER by an iteration technique. The parameters used
in the computation can differ for each soil layer.
2.3.2 Nitrogen Inputs: Atmospheric Deposition, N Applications, and N fixation
Inputs of nitrogen to the surface and subsurface soil horizons can be accommodated for
representing atmospheric deposition, nitrogen additions through fertilizer, manure, and/or
waste/sludge applications, and N fixation by leguminous plants. All nitrogen inputs are defined
in their elemental forms as NO3-N, NH4-N, and organic N; for each of the three input categories
further restrictions may apply on the form and species of the applied amounts (discussed below).
Two basic types of atmospheric deposition are simulated. Dry deposition is considered to be
a flux per unit area over the land surface which is independent of rainfall. Wet deposition is
considered to be a concentration of a nitrogen species dissolved in the input precipitation. If
data is available as a total flux only, it should be input as dry deposition. All deposition inputs
are added to the surface soil horizon, and are assumed to be input as NO3-N, adsorbed NH4-N,
and particulate labile organic N.
If atmospheric deposition is being simulated, the soil storage in the surface horizon is updated
for each of these three species of nitrogen using the formula:
N(i+l) = N(i) + ADFX + PREC*ADCN
where:
N(i) = storage of nitrogen species in the soil layer on day i, in mass/area
ADFX = dry or total atmospheric deposition flux in mass/area per interval
PREC = precipitation depth
ADCN = concentration for wet atmospheric deposition in mass/volume
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Nitrogen applications with fertilizers or manure is accomplished in a manner analogous to
pesticide applications. Application dates are specified for the entire simulation period, along
with the specific amounts of each N form ~ NO3-N, NH4-N, and organic N , the depth of
incorporation for each application, and the labile fraction of the applied organic N.
Another potential source of N inputs for both agricultural conditions and selected forest species
is N fixation from the atmosphere. This capability to represent leguminous plants (e.g.
soybeans, woody legumes, conifers) is available as an option when using the yield-based plant
uptake algorithm (described below); it will fix nitrogen from the atmosphere assuming it is an
infinite source. The algorithm is designed to allow N fixation only to make up any shortfall in
.soil nitrogen, i.e., fixation is only allowed if the available soil nitrogen (nitrate and solution
ammonium) is insufficient to satisfy the target uptake. The maximum daily nitrogen fixation rate
is subject to the same limits as the uptake under deficit conditions noted below.
2.3.3 Plant N and Uptake
Plant N simulation involves uptake of ammonium and nitrate by the plant, and "return" of plant
N to organic N in the soil. There are three optional methods for simulating plant uptake,
including the default, first-order kinetics method, a yield-based approach designed for
agricultural crops, and a Michaelis-Menten or saturation kinetics method. These options are
selected using the input flag NUPTFG.
First-Order Uptake
When NUPTFG = 0, plant uptake of soil nutrients is represented the same as in HSPF Version
No. 10, as a first-order rate process with an Arrhenius temperature correction adjustment based
on simulated soil temperatures. The first-order plant uptake rates are defined by the user, can
be specified separately for each soil layer, and can vary for each month to approximate the
monthly pattern of crop growth and nutrient uptake. The rates are adjusted during calibration
to mimic the expected annual nutrient uptake and the seasonal pattern for the specific crop and
practice. Plant uptake can be distributed between nitrate and ammonium by input parameters
intended to designate the fraction of plant uptake from each species.
Because this option uses first-order monthly uptake rates to represent time-varying plant nutrient
uptake, the calculated uptake amounts are highly sensitive to, and a direct function of, the
available nutrients in the soil profile and the specific nutrient input/application rates. This causes
a problem when application rates are changed, such as under nutrient reduction alternatives,
because the uptake amounts are not a function of expected crop yields and associated nutrient
uptake; thus, even though sufficient nutrients may be available to satisfy crop needs under the
reduced application rates, the calculated uptake may be less than the crop needs because of the
first-order formulation.
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Yield-Based Plant Uptake Option
The problems and issues related to the plant uptake algorithms in the AGCHEM modules of
HSPF, along with the primary alternative algorithms used in a number of current agricultural
nutrient models were reviewed by Donigian et al. (1995). Based on that review effort and the
compatibility of alternative functions with the AGCHEM and HSPF soil profile representation,
the plant uptake formulation in the Nitrate Leaching and Economic Analysis Package (NLEAP
model) (Shaffer et al., 1991) was selected and adapted for incorporation into AGCHEM/HSPF
Version No. 11 (Bicknell et al, 1996).
This method is referred to as the yield-based plant nitrogen uptake method, and it is selected
when NUPTFG = 1. It is designed to be less sensitive to soil nutrient levels and nutrient
application rates than the first-order rate approach (NUPTFG = 0); thus, it allows crop needs
to be satisfied, subject to nutrient and moisture availability, without being calculated as a direct
function of the soil nutrient level. This approach allows a better representation of nutrient
management practices, since uptake levels will not change dramatically with changes in
application rates.
In this method, a total annual target, NUPTGT, is specified by the user, and is then divided into
monthly targets during the crop growing season; the target is further divided into the four soil
layers. The monthly target for each soil layer is calculated as:
MONTGT = NnjPTGT!1WPTFM(MON)*NUPTM(MON)*CRPFRC(MON,ICROP)
where:
MONTGT = monthly plant uptake target for current crop, mass N/area
NUPTGT = total annual uptake target, mass N/area
NUPTFM = monthly fraction of total annual uptake target, dimensionless
NUPTM = soil horizon fraction of monthly uptake target, dimensionless
CRPFRC = fraction of monthly uptake target for current crop, dimensionless.
This is 1.0, unless the month contains parts of two or more crop
seasons, in which case the monthly uptake target is divided among the
crop's according to the number of days of the month belonging to each
crop season.
MON = current month
ICROP = index for current crop
Planting and harvesting dates can be specified for up to three separate crops during the year.
Plant uptake is assumed to occur only during a growing season, defined as the time period
between planting and harvest. When portions of two growing seasons are contained within one
month, the total monthly target is divided between the two crops in proportion to the number
of days in each season in that month. The daily target is calculated by starting at zero at the
beginning of a crop season and using a trapezoidal rule to solve for monthly boundaries; linear
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interpolation is used to solve for daily values between the monthly boundaries, and between a
monthly boundary and a planting or harvest date.
Yield-based plant uptake only occurs when the soil moisture is above the wilting point, which
is specified by the user for each soil layer, and sufficient nutrients are available. No
temperature rate adjustment is performed, but all uptake is stopped when soil temperature is
below 4 degrees C. If the uptake target is not met during a given interval, whether from
nutrient, temperature, or moisture stress, then a deficit is accumulated, and applied to the next
interval's target. When uptake later becomes possible, the program will attempt to make up the
deficit by taking up nitrogen at a rate higher than the normal daily target, up to a user-specified
maximum defined as a multiple of the target rate. The deficit is tracked for each soil layer, and
is reset to zero at harvest, i.e. it does not carry over from one crop season to the next.
Saturation Kinetics Uptake
The third option for simulating plant uptake is to use a Michaelis-Menten or saturation kinetics
method recommended for forested areas in the ORNL Study (Hunsaker et al., 1994). Thus,
whenever it is selected, the same method is also used to simulate immobilization of ammonium
and nitrate, following the ORNL recommendations. Saturation kinetics is activated for both
uptake and immobilization by setting NUPTFG to 2 or -2.
The user specifies a maximum rate and a half-saturation constant for each of the four processes
(uptake of nitrate and ammonia, and immobilization of nitrate and ammonia and for each soil
layer). The input maximum rates can vary monthly. The corresponding reaction fluxes are
computed using the general equation:
FLUX = KK * CONG / (CS + CONC)
where:
FLUX = amount of flux (mg/1/interval)
KK = temperature corrected maximum rate (ing/I/interval)
CONC = concentration of nitrogen species in soil layer (mg/1)
CS = half-saturation constant (mg/1)
The flux is then converted to units of mass per interval.
Regardless of the option used to simulate plant uptake, if the above-ground and litter
compartments are being simulated, then the user can specify the fraction of uptake from each
layer that goes to the aboveground plant N storage. The remainder is assumed to become plant
N within that soil layer.
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2.3.4 Soil and Plant Nitrogen, and Litter Compartments
In the previous version of the NITR module in HSPF AGCHEM, plant N was a single "state
variable" that represented the cumulative amount of N taken up by plants from each soil layer.
This material continues to "build up" as Plant N associated with (or derived from) each soil
layer during the simulation, i.e., it is not converted to any other species in the soil until (or
unless) a SPECIAL ACTION is imposed to represent the impacts of harvest, tillage, or other
operations. In the new version, we have added a pathway in each layer so that plant N can be
converted (by first-order rate) to organic N (labile or refractory particulate) to represent the
return of plant N to the soil through leaf fall, crop residues, and root decomposition. These
rates can be either constant or monthly variable.
The user can select between two optional scenarios for simulating plant nitrogen. If ALPNFG
= 0, plant N is simulated in each of the four standard soil layers (i.e., surface, upper, lower,
and active groundwater) as in previous HSPF versions. If ALPNFG = 1, plant N is also
simulated in aboveground and litter compartments, in addition to the standard below-ground
layers. Plant N simulation involves uptake of ammonium and nitrate by the plant, and "return"
of plant N to organic N in the soil.
Return of litter and below-ground plant N to particulate organic N is divided into labile and
refractory fractions, which can be constant or monthly variable. By using default values of the
return parameters, all plant return becomes labile organic N. Regardless of the option used to
simulate plant uptake, if the aboveground and litter compartments are being simulated, then the
user can specify the fraction of uptake from each layer that goes to the aboveground storage.
The rest is assumed to remain within the below-ground plant N compartment for that soil layer.
The N taken up by the plants can be divided between aboveground and belowground pools using
a simple fraction of the total uptake; these fractions can also be constant or monthly variable.
The aboveground plant N return would first fall into a litter compartment before returning to the
soil organic N in either the surface or upper soil layers. Both of these rates - from aboveground
N to litter and from litter to soil organic N - can be either constant or monthly variable. The
aboveground plant N and litter N are single compartments, while the belowground plant N
storage is maintained for each of the soil compartments. Note that under this option, the old
definition of plant N as the nitrogen that has been derived from a particular layer has been
modified since some of the plant N derived from a layer will be allocated to the aboveground
storage.
Thus, when ALPNFG = 1, total plant nitrogen is divided into aboveground, litter, and
belowground compartments. Aboveground plant N returns to the litter compartment, and litter
N returns to particulate organic N (with labile and refractory fractions) in the surface and upper
soil layers. Both of these reactions are simulated using first-order kinetics. No other reactions
affect these nitrogen storages except for plant uptake to the above-ground compartment, as
calculated in subroutine NITRXN.
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2.3.5 Organic Nitrogen Compartments and Reactions
The previous NITR module of AGCHEM contained a single organic N state variable in each soil
layer. This material was assumed to be a particulate species that is increased from
immobilization of nitrate and ammonia, and is converted back to ammonia by mineralization in
the soil. It also is transported on the surface by association with sediment. In the new module,
this species is described as a "particulate labile" fraction of organic N; in addition to
mineralization, it will undergo conversion by first order rate to a "particulate refractory"
fraction, and it will partition to a "soluble labile" fraction. The "particulate refractory" species
will also partition to a "soluble refractory" fraction. The two soluble species will therefore be
available for transport as runoff and leaching within the soil profile, and likewise, the new
particulate fraction will be transported on the surface with sediment.The particulate labile species
is the default form of organic N in the model; if default values of organic N-related sorption
parameters and reaction rates are used, only this form will exist.
The organic nitrogen partitioning reactions (sorption-desorption) are described by equilibrium
linear isotherms as shown in the following equations:
KLON = PLON/SLON (2)
KRON = PRON/SRON
where:
KLON and KRON = partition coefficients for the labile and refractory
organic nitrogen, respectively (-)
PLON = particulate labile organic N (Ib N/ac or kg N/ha)
SLON = solution labile organic N (Ib N/ac or kg N/ha)
PRON = particulate refractory organic N (Ib N/ac or kg N/ha)
SRON = solution refractory organic N (Ib N/ac or kg N/ha)
The four organic nitrogen forms and their assorted reactions are illustrated in Figure 2.1. Note
that the storages and transformations in this figure are generally repeated in each soil layer
except for the aboveground plant N and the litter compartments. Also, the three new organic
nitrogen state variables described above are always present in the NITR module, i.e., they are
not optional. However, in order to make the program compatible with previous versions, the
default inputs result in the three new forms maintaining zero concentrations; therefore, there
should be no impact on the simulation results of existing applications when using the current
version of HSPF.
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SECTION 3.0
REGIONAL-SCALE TESTING ON SHENANDOAH RIVER
WATERSHED MODEL SEGMENTS
3.1 TESTING OBJECTIVES, SITE, AND PROCEDURES
The objectives of this testing effort were to evaluate the behavior of the N cycling enhancements
to the AGCHEM module of HSPF, develop a reasonable model parameterization for representing
forest N storages and fluxes, and identify areas for future testing, investigation, and model
refinement. Since the study was initiated from N-related issues in the Chesapeake Bay region,
the Shenandoah River model segments were selected for regional scale-evaluation and testing of
the forest N enhancements. Figure 1.3, in Section 1.0, shows the locations of the Shenandoah
segments; the testing was limited to the forested portions of Model Segments 190 and 200,
corresponding to pervious land segments (PLSs) 191 and 201.
Model testing at a regional-scale is limited by the lack of both region-wide and forest-specific
information for comparison to model predictions that pertain only to the forested land segments
of the watershed. Thus, the testing procedures involved estimating initial model parameters
from previous experience with the AGCHEM module, prior simulations for the Shenandoah
segments, parameter guidance from the ORNL report (Hunsaker et al., 1994), and other
available literature information. To help guide the calibration effort, we developed an
'expected', or typical N balance for forested watersheds similar to the procedures used for
calibrating AGCHEM for cropland segments in the Phase II Chesapeake Bay Watershed (CBW)
Model Study (Donigian et al., 1994). Thus, we adjusted the forest model parameters to mimic
the expected N balance for forested ecosystems, including storages and transformation fluxes,
while maintaining the N export within reasonable bounds based on experience and available
literature information. The results of this effort provided the foundation for the Chesapeake Bay
Program Office application of this N balance modeling approach to all forested areas within
CBW area. In a concurrent effort, the forest N AGCHEM approach was incorporated into the
entire Shenandoah model, along with all other land uses, sources, and selected changes and
enhancements, the results of which are reported by Donigian and Chinnaswamy (1996a).
Below we describe the expected N balance we developed for forested watersheds, drawing
heavily from the study by ORNL, followed by the results of regional-scale testing on the
Shenandoah forest segments, and our conclusions and recommendations from this testing effort.
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3.2 EXPECTED FOREST N BALANCE AND STORAGES
The N balance for forest was derived primarily from information in the report by Oak Ridge
National Laboratory (ORNL) (Hunsaker et al., 1994) which was the basis for the algorithm
enhancements to AGCHEM for forest N cycling processes described in Section 2. In addition
to the design details for the model enhancements, the ORNL report included an extensive
literature review of forest N pools and fluxes, review of monitored N data from the CBW
region, and available N models. That literature review focused primarily on data collected from
two studies: the International Biological Program, which provided data on 116 forest research
sites around the world, and the Integrated Forest Study that provided 17 forest research sites (16
in North America) (Johnson and Lindberg, 1992). The information and data collected at these
sites and subsequently presented in the ORNL report formed a reasonable basis for developing
the expected N balance and storages (or N pools) shown in Table 3.1. Although additional
references were consulted (e.g. Stoddard, 1994; Johnson, 1992; Aberetal., 1989; Boring etal.,
1988; Johnson et al., 1988; Pastor and Post, 1986), the ORNL report provided the most
comprehensive basis for defining the expected forest N balance.
The information in Table 3.1 is presented in a 'production' sense by estimating the annual
INPUTS and OUTPUTS for the forest soil-plant ecosystem. The INPUTS represent external
additions to the system, such as atmospheric deposition, N-fixation, and nutrient applications
(i.e. fertilizer and manure), in addition to net mineralization from the soil that supplies plant-
available inorganic nutrients. The OUTPUTS represent various loss mechanisms, plus plant
uptake (e.g. through plant retention or harvest) that extracts the nutrients from the soil impacting
the potential for nutrient export and losses. Thus, although mineralization and plant uptake are
not truly external to the soil-plant system, they are most often key components in establishing
representative N balances for forests and most other land use/cover categories. Table 3.1 also
identifies the general magnitude of the N pools for forest systems since these are important
components of the simulation. The values in the table are not identical to those in the ORNL
report; they are provided as general ranges based on that summary and the other sources
reviewed.
Based on the review of available literature and information provided in the ORNL report, the
following discusses the ranges and associated issues presented in Table 3.1.
The primary sources of input to forests are atmospheric N deposition, with nitrogen
fixation for some species, along with plant available N (inorganic N) from
mineralization. Forest fertilization can be important in silvicultural activities and should
be included if appropriate for a specific site assessment; we have not included forest
fertilization in Table 3.1.
The major pathways by which N export losses occur include leaching from.soil and
denitrification. Also, the surface runoff losses are generally small except when the forest
system has reached higher levels of N saturation (Stoddard, 1994). Although plant
uptake is not a true 'loss' from the system, it is a key component in the overall balance.
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Table 3.1 Targets for Forest Nitrogen Balance and Storages
FLUXES: Ib/ac/yr Comment/Source*
INPUTS:
Atmospheric Deposition
N-Fixation, Fertilization
Mineralization
Mineral Soil N
Forest Floor
OUTPUTS:
Runoff, including erosion
N03
NH3
OrgN
Total
Denitrification
Leaching
OTHER FLUXES:
Plant Uptake
Plant Return
to Litter
BG to Soil N .
STORAGES:
Plant N
Above Ground (AG)
Below Ground (BG)
Litter N
SoilN
Surface Soils
Subsurface
7- 10
0
40 - 140
20-80
20-60
Cone (mg/1)
< 1 -2 < 0.5- 1.0
< 0.2 < 0.01-0.1
1-2 < 0.2-1.0
<2-4 < 0.5-2.0
< 1 -5
< 1 -5
ORNL Report
(2% - 7% of Labile Soil N/yr)
ORNL report
about lOx less than NO3
same magnitude as NO3
50 - 150
40 - 120
15-40
25-65
Ib/ac
290 - 740
230 - 580
60 - 160
20-50
2000 - 8500
700-3000(35%)
1300-5500(65%)
50/50 split AG/BG, ORNL Report
80%-90% of uptake, ORNL Report
BG/AG ratio of 1.6; ORNL Report
ORNL Report
5% to 10% of AG
ORNL Report
ORNL Report
'ORNL Report = Hunsaker et al., 1994
24
-------
The other processes that play important roles in forest N cycling are retention of
ammonium-N by soils, immobilization of available nitrogen by microorganisms, and
return of plant N to the soil both belowground and through the forest litter layer.
Since mineralization and plant uptake are such dominant components of a forest N
balance, an accurate accounting of their fluxes is critical to modeling the N cycling and
export to waterbodies. Annual mineralization was estimated as 2% to 7 % of the labile
soil organic N (Hunsaker et al., 1994). They indicated a general range of plant uptake
of 50 to 150 Ib/ac/yr, split 50/50 between above and below ground, with 80% to 90%
returned to the soil either through the litter compartment or root decay. Also, an
estimated ratio of 1.6 for below to above ground returned plant N was determined.
Plant and soil N storages cover a wide range, as shown by the values in Table 3.1.
Generally, 70% to 80% of total plant N is above ground, and about 35% of the total soil
N is in the top soil layer (down to about 20-30 cm). More than 70% of the total soil N
is relatively stable, refractory organic N.
For comparison purposes, Table 3.2 shows the typical or expected nitrogen balances for different
major crops and land cover/use categories, including forest. Concurrent with this study, and
as part of the Chesapeake Bay Program (CBP) Phase IV Watershed Model effort, the 'expected'
nutrient balances in Table 3.2 were developed to help guide the model application and calibration
effort for those land segments for which the new HSPF Version 11.0 AGCHEM module was
applied to simulate detailed nitrogen dynamics (Donigian and Chinnaswamy, 1996a). A review
of the literature was performed to develop the nutrient balances for each category, with the
primary focus on the forest, pasture, and urban categories. The nutrient balances for
agricultural croplands developed during the earlier Phase II study (Donigian et al., 1994) are
included in Table 3.2. In the recent CBW Model study, the AGCHEM sections replaced the
PQUAL sections in the Watershed Model for forest for only the N species, and for pasture for
both N and P species. Although the preliminary nutrient balances for the urban land use were
developed, the nutrient loadings from the urban segment in the Model were still simulated using
PQUAL, due to lack of detailed urban land use categories and associated N balance data
(Donigian and Chinnaswamy, 1996a).
3.3 AGCHEM FOREST N TESTING RESULTS
In testing the AGCHEM forest N enhancements at the regional-scale, no observed data was
available for just the forested portions of the Shenandoah Model segments. Consequently, we
relied heavily on the expected N balance and storages shown in Table 3.1, our past experience
in applying AGCHEM to croplands, previous simulations of the Shenandoah River Watershed
as part of the CBW Model efforts, and the general guidance provided in the ORNL report. We
started with the hydrology parameters for the forest portions of the Shenandoah segments. We
then revised these to better represent the expected forest flow regime. We estimated the initial
25
-------
Table 3.2 Typical Nitrogen Balance For Major Crops and Land Use/Land Cover Categories
(Ib/ac/yr)
Corn* Soybeans'1' Grains* Hay* Forest1 Pasture Urban
INPUTS:
Fertilizer/Manure 100-160 25-35 50-100 30-60 0 10-60' 100-200"
Atmos. Deposition 7-10 7-10 7-10 7-10 7-10 7-10 7-10
Mineralization 25-40 25-40 25-40 25-40 40-140 25-40" 25-40"
Totals 132-210 57-85 82-150 62-110 47-150 42-110 132-250
OUTPUTS:
Plant Uptake 120-150 25-402 60-90 30-55 50-150 31-803 86-1637
Surface Runoff 2-5 1-3 2-4 1-3 1-2 1-5* 5-108
Leaching & Subsurface 10-25 10-15 5-15 5-15 1-5 5-15" 13-259
Runoff
Volatilizations 15-25 5-15 10-20 10-20 1-10 7-196 30-5810
Denitrification 0
Totals 147-205 41-73 77-129 46-91 53-167 44-119 134-256
A STORAGE -15 to +5 +16 to +12 +5 to +21 +16 to +10 -6 to -17 -2 to -9 -2 to -6
Notes: See Donigian and Chinnaswamy(1996a) for references cited below -
* From Chesapeake Bay Program Phase II report (Donigian et al., 1994)
Approximately 60% of the Segments in CBP region receives 10-20 Ib/ac while about 20% receives greater
than 20 Ib/ac and the rest receives less than 5 Ib/ac (Source: M.Palace, CBPO, personal communication,
1996)
"- Since no literature data is avail-able it is assumed to be in the same range as that for hay
'- ORML Report (Hunsaker et aI.. 1994)
2- Represents uptake from the soil, approximately 25% of total .uptake, with 75% supplied by fixation
(Tisdale et al., 1985)
3- 73% uptake - average of 65-80% (Legg and Meisinger, 1982, Muchovej and Rechcigl, 1994)
4- 5% loss in surface runoff (Legg and Meisinger, 1982)
6- 17% volatilization - average of 10-25% (Meisinger and Randall, 1991); Denitrification is assumed to be
insignificant (Uoodmansee, 1978, Muchovej and Rechcigl, 1994).
6- Literature reported range for home lawns and turfgrass (Muchovej and Rechcigl, 1994,-Petrovic, 1990;
Morton et al. 1988).
7- 65 % uptake - average of 50-80% (Petrovic, 1990, Muchovej and Rechcigl, 1994).
8- 5% of total N input (Morton et al. 1988; Petrovic, 1990).
e- 10% of total N input (Muchovej and Rechcigl, 1994; Morton et al. 1988).
10- 23% of total N input (average of 10-36%) (Petrovic, 1990)
26
-------
values of the AGCHEM parameters from our past experience and available guidance in the
ORNL report, and then we adjusted the parameters in an attempt to mimic the expected storages
(e.g. soil N, aboveground (AG) plant N, belowground (BG) plant N, litter N) and fluxes (i.e.
mineralization, plant uptake, plant return to litter and soil). The goal was to achieve relatively
stable and expected patterns of the N pools and fluxes, while predicting the N export, and its
components, within or close to the expected ranges shown in Table 3.1. As shown by the
large ranges and varying magnitudes in Table 3.1, the primary difficulty in calibrating the model
is related to balancing the large storages of plant and organic nitrogen over long periods with
small inorganic storages, relatively small inputs and process fluxes, while attaining the observed
(or expected) seasonal variation in nutrient concentrations and loadings in discharge from the
watershed. In particular the seasonal timing of mineralization, plant uptake, and plant return
fluxes are critical to the plant nitrogen storage and accurate estimation of loadings.
Below we discuss the model results for the forest portion of Shenandoah model segment 190
(i.e. PLS 191) in terms of the simulation of the forest hydrology, plant and soil N storages, and
N exports. Appendix C includes the HSPF User's Control Input (UCI) for the final model run
showing the specific parameter values used to obtain these results. Parameter definitions are
included in Section 2.0, and complete descriptions of both the model algorithms, parameters,
and input formats are provided in the HSPF Version No. 11 User's Manual (Bicknell et al.,
1996).
3.3.1 Shenandoah Forest Hydrology Simulation
As noted above, the Shenandoah forest hydrology simulation was based on a slight modification
to the hydrology parameters calibrated in previous CBW modeling efforts. The parameters were
revised, based on simulations for small forested watershed sites (see Section 4.0), to produce
less surface runoff and more interflow than previously simulated, providing a better
representation of the hydrologic regime for forested watersheds. Previous modeling results
showed similar amounts for surface runoff and interflow, whereas true 'surface runoff is
relatively infrequent in forested systems with subsurface flow dominating. These refinements
only affected the distribution between surface and subsurface flow, with no significant impact
on total annual flow volumes (Donigian and Chinnaswamy, 1996b).
The hydrology simulation for this study on the Shenandoah Basin is essentially the same as was
reported by Donigian and Chinnaswamy (1996a) for the prior study; Table 3.3 shows the
hydrologic balance components for the forest lands, including the precipitation, runoff, and
evapotranspiration components, while Table 3.4 shows the annual flow comparison. On
average, total runoff is dominated by baseflow, accounting for 65% of the total, while surface
runoff is about 6% and interflow is 29%. In high flow years, such as 1985, the surface runoff
fraction reaches 12%, interflow increases to about 30%, while baseflow still represents 58% of
the total. Evapotranspiration is about 90% of the total Potential Evapotranspiration (PET) which
is common for deciduous forests in the moderate climates of the central Atlantic Coast.
27
-------
Table 3.3 Simulated Hydrologic Balance for Forest Land in Shenandoah Model Segment 190
1984 1985 1986 1987 1988 1989 1990 1991 MEAN
Precipitation 43.65 42.99 30.45 43.61 31.42 45.43 41.84 35.51 39.36
(in)
Runoff (in)
0.76
3.77
8.55
13.09
Evapot ranspirat i on(i n)
Potential 24.88 28.91 29.91 32.90 32.30 24.65 29.57 29.59 29.09
Intercep St 9.21 9.20 10.20 9.92 9.11 11.09 9.71 8.82 9.66
Upper Zone 8.73 9.30 5.20 9.15 8.96 8.81 11.23 9.28 8.83
Lower Zone 5.36 7.88 10.06 9.57 9.85 3.76 6.64 8.62 7.72
Total Actual 23.30 26.38 25.46 28.64 27.92 23.66 27.59 26.71 26.21
Surface
Interflow
Basef low
Total
1.23
6.25
10.41
17.89
1.89
4.60
8.96
15.46
0.14
1.09
6.02
7.26
0.95
4.16
8.91
14.02
0.02
0.95
6.40
7.38
0.47
5.15
10.11
15.72
0.88
4.83
9.23
14.94
0.51
3.13
8.39
12.03
Table 3.4 Shenandoah River Watershed Hydrologic Calibration: Comparison of Annual Total
Observed vs Simulated Flow for South Fork Shenandoah River at Front Royal, VA
SOUTH FORK SHENANDOAH RIVER AT FRONT ROYAL, VA (SEGMENT 190)
YEAR OBSERVED SIMULATED
FLOW (in) FLOW (in)
1984 18.60 20.05
1985 16.20 17.10
1986 7.34 7.24
1987 16.10 14.73
1988 7.71 7.06
1989 15.08 16.35
1990 13.58 15.41
1991 11.67 11.63
MEAN 13.29 13.70
28
-------
Although no observed data is available for just the forest land within Segment 190, the
hydrology simulation results for the South Fork of the Shenandoah River at Front Royal have
been presented by Donigian and Chinnaswamy (1996a). The annual flow volumes shown in
Table 3.4 and the flow-duration (cumulative frequency) curves in Figure 3.1 from that study
indicate a very good agreement with the observed data for this watershed, which is about 50%
forest. Based on these results, and the forest hydrologic balance in Table 3.3, we feel the
hydrology is simulated well enough to provide a sound basis for testing and evaluating the forest
N simulations with AGCHEM'. For interested readers, Donigian and Chinnaswamy (1996a)
provide more detailed results on the hydrology simulation of the Shenandoah Basin.
3.3.2 AGCHEM Modeling of Forest Plant N and Soil N Pools
Table 3.5 presents a summary of the AGCHEM simulation results for forest land in Shenandoah
model segment 190 for the eight-year period from 1984 to 1991. The table includes the
following:
a. annual values for runoff, sediment loss, and N export for all N forms
b. year-end storage values of various plant N pools
c. year-end storage values of all N forms in the soil layers
d. fluxes for atmospheric deposition, plant uptake, plant-to-litter, plant-to-soil, and litter-
to-soil returns
e. transformation fluxes for mineralization, denitrification, nitrification, immobilization,
and labile-to-refractory organic N conversion
f. sums and averages for the above information for the entire simulation period
This table is produced by an auxiliary software package that reads the detailed HSPF output file
and provides the summary information for calibrating and evaluating the model behavior.
Although annual values are shown in Table 3.5, time-interval (i.e. hourly), daily, and monthly
values can also be produced and evaluated as needed as part of the testing and calibration
exercise.
Clearly, the large volume of information produced by AGCHEM, which was increased
significantly with the forest N enhancements, makes it difficult to fully assess all aspects of the
complex interactions being simulated. Furthermore, the lack of data with which to evaluate each
of the fluxes and state variables in Table 3.5 further complicates model application, calibration,
and testing. In short, the more complex the model, the more data and effort required to assess
its behavior and accuracy. In this section we will discuss the simulation results of some of the
key plant and soil N pools shown in Table 3.5, in comparison to the expected range of values
from Table 3.1; the following section will address the N export results.
The behavior of various N pools is more easily analyzed with graphical displays. Accordingly,
Figure 3.2 shows the behavior of the plant N pools for the eight-year simulation period for the
aboveground (AG), belowground (BG), and Total Plant N compartments, including the litter N,
which is shown separately in the top (auxiliary) graph in the figure. Figure 3.3 shows the AG
29
-------
10°
10J
CO
Li-
CJ
S imuIo ted
Observed
LO
O
10J
10'
10
0.1 0.5 1 2 5 10 20 30 50 70 80 90 95 98 99
Percent of Time Flow Exceeded
FIGURE 3.1 FREQUENCY ANALYSIS OF FLOW AT REACH 190
SF SHENANDOAH RIVER AT FRONT ROYAL. VA
99.8
-------
Table 3.5 AGCHEM Simulation Results for Forest Land in Shenandoah Model Segment 190
u>
Rainfall (in)
Runoff (in)
Surface
Interflow
Basef low
Total
Sediment Loss (t/a)
Nutrient Loss (Ib/a)
N03 Loss
Surface
Interflow
Basef low
Total
NH3 Loss
Surface
Interflow
Basef low
Sediment
Total
Labile ORGN
Surface
Interflow
Basef low
Sediment
Refrac ORGN
Surface
Interflow
Basef low
Sediment
Total ORGN Loss
Total N Loss (Ib/a)
STORAGES (Ib/ac)
AG Plant N
Litter N
BG Plant N Storage
Surface
Upper
Lower
1984
43.65
1.232
6.246
10.41
17.89
0.1600
0.3545E-01
0.7217
1.189
1.946
0.3668E-01
0.5717E-01
0.4030E-01
0.6773E-03
0.1348
0.4898E-01
0.3889
0.2430
0.1235
0.2696E-01
0.2141
0.1678
0.4967
1.710
3.791
538.3
28.42
20.15
212.7
69.40
1985
42.99
1.891
4.603
8.962
15.46
0.7296E-01
0.1929E-01
0.5538
1.217
1.790
0.2520E-01
0.4315E-01
0.4820E-01
0.2860E-03
0.1168
0.4039E-01
0.2668
0.2365 .
0.5586E-01
0.2118E-01
0.1573
0.1680
0.2143
1.160
3.067
571.9
28.69
20.40
225.4
82.68
1986
30.45
0.1440
1.092
6.022
7.258
0.3054E-01
0.5665E-02
0.4687
1.027
1.501
0.4838E-02
0.2101E-01
0.4486E-01
0.1303E-03
0.7084E-01
0.7433E-02
0.7263E-01
0.2305
0.2662E-01
0.3757E-02
0.4437E-01
0.1686
0.9693E-01
0.6508
2.223
607.3
29.82
20.61
236.4
91.01
1987
43.61
0.9480
4.164
8.910
14.02
0.6364E-01
0.3658E-01
0.5174
1.621
2.175
0.2184E-01
0.3907E-01
0.4773E-01
0.2803E-03
0.1089
0.3461E-01
0.2255
0.2242
0.5298E-01
0.1679E-01
0.1463
0.1691
0.1870
1.057
3.340
634.0
31.13
20.82
246.0
96.42
1988
31.42
0.2200E-01
0.9530
6.403
7.378
0.1476E-02
0.3524E-02
0.1784
0.8825
1.064
0.1329E-02
0.1141E-01
0.4039E-01
0.3406E-05
0.5313E-01
0.2975E-02
0.6618E-01
0.2193
0.6179E-03
0.1406E-02
0.4449E-01
0.1702
0.2142E-02
0.5073
1.625
653.7
32.26
20.98
250.8
98.03
1989
45.43
0.4680
5.146
10.11
15.72
0.1010
0.1743E-01
0.2838
0.9639
1.265
0.2974E-01
0.2144E-01
0.4072E-01
0.4733E-03
0.9237E-01
0.3255E-01
0.2743
0.2129
0.8584E-01
0.1479E-01
0.1897
0.1702
0.2861
1.266
2.624
664.9
33.12
21.20
254.6
98.29
1990
41.84
0.8820
4.827
9.233
14.94
0.6175E-01
0.1620E-01
0.4583
0.2146
0.6891
0.2389E-01
0.3347E-01
0.3613E-01
0.2433E-03
0.9373E-01
0.3660E-01
0.2529
0.2083
0.5086E-01
0.1620E-01
0.1765
0.1708
0.1647
1.077
1.860
678.3
33.88
21.39
257.8
96.75
1991
35.51
0.5140
3.132
8.387
12.03
0.4677E-01
0.2390E-01
0.5710
0.2633
0.8581
0.2375E-01
0.4160E-01
0.3271E-01
0.2117E-03
0.9828E-01
0.2577E-01
0.1639
0.2038
0.3849E-01
0.1127E-01
0.1150
0.1713
0.1228
0.8523
1.809
690.6
34.56
21.54
259.9
94.74
SUM/AVER
39.36
0.7626
3.770
8.554
13.09
0.6727E-01
0.1975E-01
0.4691
0.9223
1.411
0.2091E-01
0.3354E-01
0.4138E-01
0.2882E-03
0.9611E-01
0.2866E-01
0.2139
0.2223
0.5435E-01
0.1404E-01
0.1360
0.1695
0.1963
1.035
2.542
629.9
31.49
20.89
243.0
90.91
Total AG, BG, Litter 868.9 929.1 985.1 1028. 1056. 1072. 1088. 1101. 1016.
Total Soil, Litter,
& Plant N Storage 6527. 6533. 6538. 6544. 6550. 6557. 6564. 6569. 6548.
-------
Table 3.5 Continued
NH4-N SOLN STORAGE
Surface 0.0000
Upper 0.4900E-01
Interflow 0.0000
Lower
GW
Total
NH4-N ADS STORAGE
Surface
Upper
Lower
GW
Total
N03/2-N STORAGE
Surface
Upper
Interflow
Lower
GW
Total
Labile ORGN(SOLN)
Surface
Upper
J-0 Interflow
N3
Lower
GW
Total
Labile ORGN(ADS)
Surface
Upper
Lower
GW
Total
Refrac ORGN(SOLN)
Surface
Upper
Interflow
Lower
GW
Total
Refrac ORGN(ADS)
Surface
Upper
Lower
GW
Total
0.9000E-01
0.8000E-02
0.1480
0.2760
7.663
6.347
5.231
19.52
0.3000E-02
1.117
0.1100E-01
1.291
0.1970
2.619
0.1100E-01
0.1170
0.1000E-02
0.5600E-01
0.4300E-01
0.2280
49.90
525.1
250.3
195.5
1021.
0.6000E-02
0.6700E-01
0.1000E-02
0.3700E-01
0.3000E-01
0.1410
196.7
2208.
1206.
1004.
4615.
0.0000
0.3000E-01
0.0000
0.7000E-01
0.6000E-02
0.1060
0.2840
7.460
6.257
5.097
19.10
0.1810
0.2530
0.0000
0.5940
0.1650
1.192
0.1100E-01
0.1110
0.0000
0.4700E-01
0.4200E-01
0.2120
51.46
498.8
212.5
190.8
953.6
0.6000E-02
0.6700E-01
0.0000
0.3700E-01
0.3100E-01
0.1400
194.9
2215.
1212.
1007.
4629.
0.0000
0.4600E-01
0.1000E-02
0.6300E-01
0.1800E-01
0.1280
0.2640
7.608
6.277
5.628
19.78
0.8800E-01
1.054
0.1900E-01
1.995
0.6530
3.809
0.1200E-01
0.1030
0.2000E-02
0.4100E-01
0.4100E-01
0.1980
53.66
462.3
183.1
185.1
884.2
0.6000E-02
0.6700E-01
0.1000E-02
0.3700E-01
0.3100E-01
0.1420
193.4
2224.
1217.
1011.
4645.
0.0000
0.3700E-01
0.1000E-02
0.5100E-01
0.1000E-01
0.9900E-01
0.2690
7.481
6.213
5.269
19.23
0.9000E-02
0.5710
0.1300E-01
0.5270
0.2480
1.368
0.1200E-01
0.9800E-01
0.2000E-02
0.3600E-01
0.4000E-01
0.1880
54.92
439.3
160.7
180.8
835.7
0.6000E-02
0.6800E-01
0.2000E-02
0.3700E-01
0.3100E-01
0.1430
191.3
2232.
1221.
1014.
4659.
0.0000
0.3800E-01
0.0000
0.4600E-01
0.8000E-02
0.9200E-01
0.2820
7.716
6.245
5.625
19.87
0.8100E-01
0.5600
0.1000E-02
0.3880
0.2750
1.304
0.1300E-01
0.9500E-01
0.0000
0.3200E-01
0.3900E-01
0.1780
56.37
426.4
142.6
175.9
801.2
0.6000E-02
0.6800E-01
0.0000
0.3700E-01
0.3100E-01
0.1420
189.6
2239.
1225.
1018.
4671.
0.3000E-02
0.3100E-01
0.2000E-02
0.3400E-01
0.6000E-02
0.7600E-01
0.2630
7.354
6.116
5.127
18.86
0.0000
0.3640
0.3000E-01
0.8500E-01
0.4400E-01
0.5240
0.1300E-01
0.9500E-01
0.8000E-02
0.2900E-01
0.3800E-01
0.1820
56.99
425.6
128.6
172.0
783.2
0.6000E-02
0.6800E-01
0.6000E-02
0.3700E-01
0.3100E-01
0.1480
187.4
2244.
1229.
1021.
4682.
0.0000
0.3700E-01
0.2000E-02
0.3200E-01
0.8000E-02
0.7800E-01
0.2610
7.440
6.119
5.142
18.96
0.9000E-02
0.6260
0.3700E-01
0.2450
0.9000E-01
1.006
0.1300E-01
0.9300E-01
0.6000E-02
0.2600E-01
0.3700E-01
0.1750
57.82
418.7
117.1
168.2
761.8
0.6000E-02
0.6800E-01
0.4000E-02
0.3700E-01
0.3100E-01
0.1460
185.4
2251.
1232.
1024.
4693.
0.0000
0.4300E-01
0.1000E-02
0.3100E-01
0.1100E-01
0.8600E-01
0.2590
7.583
6.148
5.446
19.44
0.2700E-01
0.9590
0.2600E-01
0.6500
0.2400
1.902
0.1300E-01
0.9100E-01
0.2000E-02
0.2400E-01
0.3600E-01
0.1670
59.53
410.8
107.5
164.1
741.9
0.6000E-02
0.6800E-01
0.2000E-02
0.3700E-01
0.3100E-01
0.1440
183.6
2258.
1236.
1027.
4704.
0.3750E-03
0.3887E-01
0.8750E-03
0.5212E-01
0.9375E-02
0.1016
0.2697
7.538
6.215
5.321
19.34
0.4975E-01
0.6880
0.1712E-01
0.7219
0.2390
1.716
0.1225E-01
0.1004
0.2625E-02
0.3637E-01
0.3950E-01
0.1910
55.08
450.9
162.8
179.1
847.8
0.6000E-02
0.6762E-01
0.2000E-02
0.3700E-01
0.3088E-01
0.1433
190.3
2234.
1222.
1016.
4662.
-------
Table 3.5 Continued
FLUXES (Ib/ac)
Atmos Dep(lb/ac)
NH3-N
N03-N
ORGN
Plant Uptake
Above Ground
NH3 Uptake
N03 Uptake
Below Ground
NH3 Uptake
N03 Uptake
Above Ground Plant
N to Litter
Litter N Return
to Labile ORGN
Surface
Upper
Total
to Refrac ORGN
Surface
Upper
Total
BG Plant N Ret
to Labile ORGN
Surface
Upper
Lower
Total
to Refrac ORGN
Surface
Upper
Lower
Total
L/R ORGN Conversion
LORGN Mineralization
Denitrification
NH3 Nitrification
NH3 Immobilization
N03 Immobilization
2.245
6.639
0.6068
48.30
8.107
47.84
11.65
18.11
14.03
2.070
6.417
0.6070
45.49
7.318
46.59
10.65
19.26
13.13
1.775
6.019
0.6070
45.54
10.35
45.13
14.26
20.48
2.204
6.635
0.6070
39.66
8.482
40.35
12.52
21.44
1.852
5.997
0.6068
35.43
6.464
35.29
8.150
22.14
2.618
7.040
0.6070
28.21
5.532
28.93
7.493
22.53
2.130
6.498
0.6070
31.59
4.742
32.98
6.537
22.98
13.62
11.87
10.68
9.122
9.715
1.833
6.097
0.6070
30.79
4.906
31.29
6.960
23.39
9.463
2.091
6.418
0.6069
38.13
6.988
38.55
9.778
21.29
5.953
12.76'
18.71
0.3133
0.6713
0.9846
5.739
12.30
18.04
0.3021
0.6473
0.9493
5.848
12.53
18.38
0.3078
0.6595
0.9673
6.087
13.04
19.13
0.3204 .
0.6865
1.007
6.350
13.61
19.96
0.3342
0.7162
1.050
6.550
14.04
20.58
0.3447
0.7387
1.083
6.717
14.39
21.11
0.3535
0.7576
1.111
6.864
14.71
21.57
0.3613
0.7742
1.135
6.264
13.42
19.68
0.3297
0.7064
1.036
0.0000
17.51
8.401
25.91
0.0000
0.9215
0.4422
1.364
0.0000
18.77
10.64
29.41
0.0000
0.9878
0.5599
1.548
0.0000
25.86
12.07
37.93
0.0000
1.361
0.6355
1.996
0.0000
22.59
13.08
35.68
0.0000
1.189
0.6885
1.878
0.0000
21.49
13.55
35.04
0.0000
1.131
0.7133
1.844
0.0000
16.94
13.62
30.56
0.0000
0.8915
0.7169
1.608
0.0000
22.26
13.50
35.75
0.0000
1.171
0.7103
1.882
0.0000
22.90
13.26
36.16
0.0000
1.205
0.6976
1.903
0.0000
21.04
12.27
33.31
0.0000
1.107
0.6455
1.753
11.45
118.0
0.0000
19.01
4.735
3.928
109.4
0.0000
15.68
4.068
3.763
118.5
0.0000
25.66
3.189
2.955
98.77
0.0000
17.61
3.821
3.511
85.22
0.0000
12.41
3.260
2.791
66.97
0.0000
9.390
3.983
2.921
75.42
0.0000
8.958
3.823
3.006
74.43
0.0000
10.17
3.431
2.642
93.34
0.0000
14.86
3.789
3.190
-------
Table 3.6 Simulated Changes in Forest N Pools from 1984 to 1991 for the Shenandoah Segment
INITIAL FINAL TOTAL MEAN ANNUAL
STORAGE STORAGE CHANGE CHANGE
(IbN/ac) (IbN/ac/yr)
Aboveground Plant N 500
Litter N 30
Belowground Plant N 270
Total Plant N 800
Labile Soil N 1100
Refractory Soil N 4600
Total Soil N 5700
TOTAL N 6500
691
35
376
1102
742
4704
5446
6548
191
5
106
302
-358
104
-254
48
23.9
0.6
13.3
37.8
-44.8
13.0
-31.8
6.0
and BG plant N pools at expanded scales for 1984-85 to demonstrate the seasonal pattern of
uptake changes. In Figure 3.4 we show the soil N components, including Total N, labile soil
organic N, and refractory soil organic N; Total plant N is also shown for comparison and to
complete the total N balance. Table 3.6 shows the initial and final N storages for the various
plant and organic N pools, along with the total and mean annual changes during the simulation.
Our review of these results indicates the following:
a. The N storages and fluxes were calibrated to generally fall within the ranges identified
as the expected N balance in Table 3.1. The export (discussed in Section 3.4), plant
uptake, plant return, and mineralization are all within the expected ranges. The various
plant and organic N storages also compare well with the values in Table 3.1, however
some differences are noted. The BG plant N is higher, and Total Soil N is near the high
end of the ranges in Table 3.1 for two reasons: first, the simulated soil core is deeper
than most soil N data; and second, soil data from Johnson and Lindberg (1992) for
selected IPS sites such as the Coweeta site were used for estimating initial storages. The
simulated soil core includes 120 cm down to the bottom of the lower zone (i.e. surface,
upper, and lower soil zones), and another 150 cm for the shallow groundwater zone;
most soil core data from Johnson and Lindberg do not exceed 100 cm. Also, a few of
the IPS sites near the Shenandoah Basin showed relatively higher BG and soil N values.
34
-------
u>
o
I
CO
40
20
0
1.500
1,350
1,200
1,050
900
750
600
450
300
150
0
AG PLANT N
BG PLANT N
TOTAL PLANT N
j_
_l_
I
I
1984 1985 1986 1987 1988 1989 1990 1991
FIGURE 3.2 SIMULATED FOREST AG, BG, LITTER AND TOTAL PLANT N IN
SHENANDOAH SEGMENT 190
-------
OJ
d
2=
=>
O Z
ce.
350
300
250
600
590
580
570
560
550
540
530
520
510
500
I I I I I I I I I I I I I I I I I I
I I I I
M
M
SO
JJASONDJFMAMJJA
1984 1985
FIGURE 3.3 SIMULATED FOREST ABOVE GROUND AND BELOW GROUND PLANT N IN
SHENANDOAH SEGMENT 190
-------
«£
I
Q-
6600
6390
6180
5970
5760
5550
5340
5130
4920
4710
4500
1,500
1,410
1,320
1 ,230
1 .140
1,050
960
870
780
690
600
TOTAL N
REFRACTORY N
TOTAL PLANT N
LABILE N
1984 1985 1986 1987 1988 1989 1990 1991
FIGURE 3.4. SIMULATED LABILE, REFRACTORY, TOTAL PLANT N AND TOTAL N STORAGE
IN SHENANDOAH SEGMENT 190
-------
b. Table 3.5 and Figure 3.2 show that the plant N pools are generally increasing each year
over the eight-year simulation period. The AG plant N increases about 24 Ib N/ac/yr,
while the BG increases about 13 Ib N/ac/yr, corresponding to about a 5% annual
increase. The litter N shows the expected cyclic pattern with increases due to leaf fall
in October-November, and gradual decomposition and return to the soil dominating the
rest of the year. The general patterns and magnitudes of the plant N pools all look
reasonable, but unfortunately no data was available to confirm the simulation.
c. The AG seasonal uptake pattern is shown at an expanded scale in Figure 3.3. Our
experience with N uptake by agricultural crops would indicate a more s-shaped curve
should be expected, with steeper uptake during leaf-out in the spring and a leveling of
the curve in summer and fall prior to leaf fall as litter. Adjustments to the monthly
maximum N uptake rates did not significantly improve the shape, indicating that the
uptake may be more controlled by the seasonal availability of inorganic N than the input
rates. This should be pursued further, along with identification of any literature data on
seasonally of N uptake in forests.
d. Figure 3.4 shows increases for Total N, refractory organic N, and Total Plant N, while
the labile organic N decreases significantly, about 45 Ib N/ac/yr or 4% annually (from
Table 3.6). This is due to the difference between the mineralization and runoff losses
from the labile N pool, less the gains from BG plant return and immobilization. It is not
clear that the labile N pool should decrease to the extent shown in Figure 3.4; further
calibration and investigation is needed, perhaps by increasing immobilization and BG
plant return to limit the labile N decreases. In these simulations we limited the labile-
refractory conversion to minimal levels because of the continuous decreases in the labile
N pool.
e. There is very little data on organic N partitioning between dissolved and particulate
forms for both the labile and refractory pools. In these simulations we adjusted the
partition coefficients to limit the dissolved organic N to the expected ranges identified in
Table 3.1. Also, little data was found on organic N for comparison with the runoff
concentrations, and no information was found on the relative levels of the distribution
between the labile and refractory forms. More investigation is needed here also.
f. The primary fluxes, such as plant uptake, plant to litter, and return to soil from both the
litter and BG pools are well within the expected ranges. In addition the ratio of the
below ground return to the litter return is close to the 1.6 value recommended by the
ORNL report (Hunsaker et al., 1994). Due to the continuous drop in labile N, the
mineralization flux decreases throughout the simulation period. Figure 3.5 shows the
monthly mineralization fluxes and the seasonal pattern due to the air/soil temperature
variation. Low levels of mineralization are simulated throughout the year due to the
moderate (i.e above-freezing) temperatures in the lower soil and groundwater zones.
Further investigation is needed to determine to what extent mineralization occurs, and
what levels should be simulated, in these deeper soil zones. Since no plant uptake and
38
-------
30
25
^20
15
10
1984
1985
1986
1987
1988
1989
1990
1991
FIGURE 3.5 SIMULATED FOREST MONTHLY MINERALIZATION RATE IN
SHENANDOAH SEGMENT 190
-------
very little immobilization is simulated for the groundwater zone (based on the current
parameter values), any mineralization in this zone directly contributes to export of both
NH3 and NO3.
g. It is interesting to note that the change in Total N (i.e. total soil N and Plant N) in Table
3.6 is about 6 Ib N/ac/yr, which corresponds very closely (within 0.5 Ibs) to the
difference between the atmospheric deposition flux of 9 Ib N/ac/yr and the runoff export
of 2.5 Ib N/ac/yr. Thus, without other inputs (e.g. fixation, fertilization) or losses (e.g.
denitrification, volatilization), the net gain or loss from the system, after all the internal
plant-soil cycling, is simply the deposition minus the runoff.
3.3.3 AGCHEM Modeling of Forest N Export
Figure 3.6 shows the simulated monthly concentrations for NO3-N, NH3-N, and Organic N from
forests in Shenandoah model segment 190. These values were developed by averaging the
hourly simulations to daily and then monthly values for the entire eight-year simulation period.
These are concentrations in the runoff from the forest land, and are input values to the stream
reach in model segment 190. As noted earlier, since we do not have runoff data for just the
forest land, no observed values are shown in the figure. The loading rates for each N form (in
Table 3.5) are consistent with the expected ranges from Table 3.1, and the concentrations are
generally within the ranges reported for forests in the ORNL report (Hunsaker et al., 1994).
The seasonal patterns, which are evident for NO3-N and somewhat less obvious for NH3-N,
are indicative of the patterns for Stage 0 and Stage 1 of nitrogen saturation described by Aber
et al. (1989) and Stoddard (1994), and this is consistent with the conclusions of Hunsaker et al.
(1994) for forests in the CBW. The Organic N concentrations are relatively constant with some
increase in fall and winter. This is expected as the organic forms are primarily paniculate with
very high partition coefficients, producing low soluble organic N concentrations. One concern
about the seasonal pattern is that for some years (e.g. 1986 to 1988) concentrations begin
increasing earlier than expected; that is, in July and August, whereas September and October
would be expected based on decreases in plant uptake. Further improvements to the plant uptake
patterns may also help improve this timing, as recommended above.
The highest NO3-N concentration values, exceeding 2.0 mg/1 during the fall-winter months of
1986-87 and 1988-89, occur during extreme low flow periods and thus contribute very little to
the annual load. However, these high concentrations also indicate that subsurface sources, such
as mineralization in the lower soil zones, may be over-estimated; the highest NH3-N
concentrations also occur during these time periods, further pointing to this conclusion. Also,
simulation of low flows may be contributing to these peaks, or insufficient immobilization.
These issues need to be further investigated.
40
-------
0.2
0.15
0.1
i
ro
n:
0.05
5
4
<4
CO
3 3
CO
o 3
S 2
S Z
CJ
^^ 4
Z 1
0
SIM N03-N
SIM ORGANIC N
1984
1985
1986
1987
1988
1989
1990
1991
FIGURE 3.6 SIMULATED MONTHLY N03-N, ORGANIC N AND NH3-N CONCENTRATIONS
FROM FORESTS IN SHENANOOAH SEGMENT 190
-------
3.4 CONCLUSIONS AND RECOMMENDATIONS
Based on the results of our Shenandoah simulations presented above, the following conclusions
and recommendations are offered for consideration:
a. The enhancements to the AGCHEM module of HSPF for simulating N cycling in
forested systems have provided a reasonable representation of both the N export, internal
cycling, and various N pools, or storages expected for the forested portions of the
Shenandoah Basin. Application at this large, regional scale has been hampered by
limited relevant data at this scale for both parameterization and calibration. However,
the expected export of the various N forms, and the overall N balance and pools, are
within expected ranges and the mass-balance framework provides a sound basis for
nutrient management issues within the Chesapeake Bay Watershed.
b. The modeling showed that for forested systems with atmospheric deposition as the only
input (i.e. no N fixation) and watershed export as the only loss (i.e. no denitrification or
leaching), the net impact or change in the Total N of the ecosystem was essentially equal
to the difference in these two fluxes, i.e. atmospheric deposition minus N export.
Closing this simple mass balance, after all the internal fluxes and transformations,
confirmed the functioning of the code changes and, with the relatively low N export
identified these forested areas as being in the early stages (i.e. stage 0 or 1) of N
saturation as represented in our simulations.
c. Plant uptake of N by forests is a key component of the cycling process. The new
AGCHEM module allows the user to define a seasonality pattern for the uptake and
adjust the parameters to obtain appropriate annual uptake fluxes. However, the seasonal
uptake pattern produced in this study appeared to be more linear with time than the
expected s-shaped pattern with the largest uptake fluxes during leaf-out in early spring
and summer. Further calibration and/or investigation of alternative options within
AGCHEM (e.g. first-order rates, yield-based) should be pursued to improve the N uptake
timing during the year. This may also help refine the seasonal pattern of the export of
both nitrate and ammonia.
d. Because there are wide ranges in the magnitudes of N storages in the various plant and
soil pools, depending on soil conditions, climate, stand age, tree species, etc., more
detailed information is needed for these state variables for application of the model to
both specific regional and small-site scales. Based on the ORNL report and selected IPS
sites, the model testing used values that were consistent with the expected range but
whose accuracy was unknown. Future testing should focus on sites with more
comprehensive data on the forest N pools (see future testing recommendations below).
e. The AGCHEM enhancements for representation of soil organics expanded the single
particulate organic N pool into four separate pools for dissolved and particulate forms
of both labile and refractory organic N. This helped to allow export of dissolved organic
42
-------
N (DON) which is a significant component of the total N export from forested areas.
The DON export values produced by the model are reasonable and within expected
ranges, but the soil storages need further investigation. Our simulations showed labile
N continually decreasing during the simulation period due to the expected range of
mineralization fluxes or lack of sufficient immobilization and plant return to the labile
pool. More calibration, soil organic data, and process investigation is needed to better
define the fractionation into the various organic N pools, partitioning between the
dissolved and paniculate forms, conversion mechanisms between the labile and refractory
forms, and appropriate changes in storages with time in forested ecosystems.
f. The AG, BG, and plant litter N pools included in the new AGCHEM module provide a
more realistic approach to N uptake and subsequent disposition of plant material and
residues, and their impact on soil N levels. Our simulations produced realistic patterns
of seasonal changes in these pools without actual site data for confirmation. Increases
in both the AG and BG plant N, and the cyclic pattern of litter N were reasonable, but
more data is needed to validate and better define the plant return pathways through the
litter compartment and from the BG pool to the soil.
g. Further model testing work is recommended to pursue the issues described above. These
testing efforts should focus on watershed sites where observed data is available for more
complete model parameterization and calibration of storages (plant, litter and soil),
important fluxes (i.e. mineralization, immobilization, plant uptake and return), and export
of all N forms, including both inorganic and organic N. The most appropriate sites
would include the type of pool and flux data collected at the IPS sites, in combination
with meteorologic and hydrologic monitoring to provide the complete database needed
to determine N export and support watershed modeling. Potential sites with these
characteristics that should be considered include the IPS sites at the Coweeta Hydrologic
Laboratory, NC; the Walker Branch Watershed, Oak Ridge, TN (Johnson and Van
Hook, 1989); the well-known Hubbard Brook watershed, NH; and other IPS sites where
detailed meteorologic and hydrologic monitoring is performed.
43
-------
SECTION 4.0
SMALL WATERSHED SITE TESTING OF FOREST N MODELING
4.1 TESTING OVERVIEW
Testing of the N cycle enhancements to the AGCHEM module for forested watersheds first
involved selection of test watersheds and then application of HSPF to the sites following the
standard application procedures described by Donigian et al (1984). Site selection was based
on information and data reviewed by Hunsaker et al (1994) in their assessment of forest N
loadings within the Chesapeake Bay Watershed; their report identified a number of forested
watershed sites, along with the data collection programs, which provided a list of potential sites
for our testing efforts.
Following site selection, the HSPF application procedures were followed to set the stage for the
testing and evaluation phase of the AGCHEM N cycle modeling on the test sites. The primary
components of the HSPF application procedures involved in this testing study included database
development, watershed segmentation and parameterization, hydrologic and sediment calibration,
and nonpoint source and water quality calibration. Since our test sites were chosen to be
essentially all forests, the nonpoint source and water quality calibration involved detailed
examination of the forest N cycle fluxes and storages (as described in Section 3.0), along with
the comparison of the simulated and observed N concentrations at the watershed outlet. In brief,
the goal was to mimic the expected N balance for the forest land segments while closely
approximating the N concentrations representing the N export from the test site.
In this section, we describe our efforts on all the above-mentioned tasks. Section 4.2 describes
the test sites, the development of the data used in the modeling, and the watershed
parameterization for each test site. Next, the hydrologic calibration is presented and discussed
in Section 4.3, followed by the AGCHEM N cycle testing and results in Section 4.4. Finally,
summary conclusions and recommendations are presented in Section 4.5.
4.2 TEST SITES, DATABASE, AND PARAMETERIZATION .
Figure 1.3 in Section 1 showed the locations of the two test sites selected: Hunting Creek
Tributary near Foxville, MD (USGS Gage No. 01640970), and Young Woman's Creek near
Renovo, PA (USGS Gage No. 01545600). Both sites were selected because they are almost
entirely forested and have been monitored by the U.S. Geological Survey for both streamflow
44
-------
and water quality for at least 10 years; the simulation period was 1984 to 1991 to coincide with
the Chesapeake Bay Watershed database. The Hunting Creek site is a small, 4.01 sq.mi.
watershed in northcentral Maryland located within the Catoctin Mountains, and it has been part
of the National Acid Precipitation Assessment Program (NAPAP) (Rice and Bricker, 1995; Rice
et al., 1993; Katz et al., 1985). Young Woman's Creek is significantly larger, at 46.2 sq. mi.,
located in northcentral Pennsylvania, and is part of the USGS hydrologic benchmark station
program. Below we describe the data and information available for modeling each of these sites,
first for Hunting Creek and then Young Woman's Creek.
4.2.1 Hunting Creek, MD
Figure 4.1 shows the watershed of Hunting Creek Tributary near Foxville, MD, and the
locations of the data stations used in the simulation, while Table 4.1 summarizes the available
meteorologic, streamflow and water quality timeseries data. The only additional stations listed
in Table 4.1 include the Unionville, MD hourly precipitation gage, located about 20 miles
southeast of the site, and Dulles Airport which is about 50 miles directly south. Since the
Hunting Creek site is contained within Segment 750 of the Chesapeake Bay Watershed (CBW)
Model, much of the meteorologic database developed for the CBW Model was used in this
modeling effort (Donigian et al., 1994). However, the hourly precipitation and air temperature
data collected at the site were analyzed and compared with the available CBW data. Below we
discuss the collection and development of hourly precipitation, air temperature and other
meteorologic data in detail.
Hourly Precipitation Data
Development of reliable precipitation data is critical because it is the principal driving force for
the model simulation. Two types of precipitation data were available for the Hunting Creek
watershed; hourly precipitation data recorded by the National Climatic Data Center (NCDC) at
Catoctin Mountain Park, and daily precipitation recorded by U.S.G.S. at the location shown in
Figure 4.1. The NCDC hourly precipitation data contained incomplete records (i.e missing
values) for some months. To fill in these missing records, we used the U.S.G.S METCMP
program (Lumb and Kittle, 1995) to disaggregate the U.S.G.S. daily rainfall data based on the
distribution at Unionville, the NCDC hourly station 20 miles southeast of Catoctin Mountain
Park. The disaggregated data were then inserted in the missing periods in the hourly
precipitation data recorded by NCDC to provide the complete hourly timeseries used in the
simulation.
Air Temperature
Daily maximum and minimum air temperature data were received for the Catoctin Mountain
Park station from NCDC. Again using METCMP, the daily maximum and minimum
temperature were converted to hourly air temperature based on a sinusoidal curve with the daily
minimum at 6 AM and maximum at 4 PM. Since the daily temperature data had missing values
for October and November 1991, for this period we used the air temperature values from the
45
-------
EXPLANATION
$ Atmospheric deposition
station
f Surlace water and
water quality stations
«. Walerslied boundary
CLIMATOLOGICAL
STATION
USGS STATION
f USGS Gage #01640970
Sludy Area
Frederick County.
Maryland PENNSYLVANIA
VIRGINIA
KIIOMUU\
Figure 4.1 Hunting Creek Watershed and Monitoring Stations
-------
Table 4.1 Meteorologic, Streamflow and Water Quality Data for Simulation of Hunting Creek Tributary near Foxville, MD
DATA TYPE
Precipitation
Catoctin Mtn
Unionville
Air Temperature
Evaporation
Solar Radiation
Wind Movement
Dewpoint
Temperature
Streamflow
Water Quality
Snow Depth
LOCATION
Catoctin Mtn Park
USGS Station
Unionville, MD
Catoctin Mtn Park
Dulles Airport
(Washington, DC)
Dulles Airport
Dulles Airport
Dulles Airport
Foxville, MD
Foxville, MD
Catoctin Mtn Park
PERIOD OF
RECORD
1/80-7/94
1/82-12/91
' 1/80-7/94
1/80-08/91
12/91-12/94
1/84-12/91
1/84-12/91
1/84-12/91
1/84-12/91
1/84-9/91
2/81-8/94
1/80-12/94
TIME
INTERVAL
Hourly
Daily
Hourly
COMMENT
NCDC data
Used to fill in missing NCDC data periods
Used for disaggregation of USGS data
Daily(Max/Min) Missing data filled with
CBW's Region 5 data
Daily
Hourly
Hourly
Daily
Daily
Random
Daily
Data from Region 5 of CBW
(Donigianetal., 1994)
Data from Region 5 of CBW
Data from Region 5 of CBW
Data from Region 5 of CBW
USGS data
USGS data
NCDC data
-------
CBW data base for this region (i.e. CBW Meteorologic Region 5). Average elevation of the
watershed is approximately 1500 ft and the elevation of the air temperature gage is 1610 ft. The
small correction needed in the air temperature values due to this elevation difference is
performed by the ATEMP module in HSPF.
Potential Evapotranspiration
Potential evapotranspiration from the CBW data base corresponding to region 5 was used in the
calibration (Donigian et al., 1994). The Penman (1948) method was used in the computation
of pan evaporation. The method, as described by Kohler et al. (1955), uses daily inputs of solar
radiation (Langleys), wind speed (miles/day), dew point (F), and average air temperature (F).
The average air temperature is defined here as the mean of the maximum and minimum daily
values. All the input data were collected at Dulles Airport (Washington, DC). Development
of the regional evapotranspiration data set was accomplished using the following two-step
procedure.
1. Regional daily pan evaporation totals were computed using the Penman method.
2. Monthly adjustment factors (i.e. pan coefficients) were developed to transform the pan
evaporation to potential evapotranspiration, while accounting for an apparent
overprediction by the Penman method for winter months.
Other Meteorologic Data
The hourly wind speed data from the CBW data base was used in the data base development.
The daily wind speed recorded at National Airport (Washington, DC) was distributed to hourly
values using a slight diurnal variation having a constant, minimum value from midnight to 7
AM, followed by a diurnal variation with a maximum at 3 PM (Donigian et al., 1990). Also,
the hourly solar radiation, the daily cloud cover and dewpoint temperature data developed for
the CBW were used in this study (Donigian et al., 1994).
Flow. Water Quality and Atmospheric Deposition Data
Daily streamflow data was available for Hunting Creek Tributary from January, 1984 through
September, 1991. For October through December, 1991, streamflow data from Hunting Creek
were multiplied by the ratio of the drainage area of Hunting Creek tributary to that of Hunting
Creek. In addition to that, monthly water quality data for nitrate, ammonia, and water
temperature were available from 1981 through 1994. No sediment data was available.
As mentioned above, atmospheric deposition data developed for the modeling of CBW were used
in this modeling effort. For the simulation of Hunting Creek tributary, the data corresponding
to Segment 750 (Monocacy basin) was obtained from the CBW data base. It should be noted
that the forested watershed that encompasses Hunting Creek falls within the segment 750 of
Chesapeake Bay Watershed Model. Wet and dry nitrate, ammonia and organic N deposition
data were available in pounds/day.
48
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Characterization of the Channel System
Characterization of the channel system for HSPF simulations is normally based on measured
channel cross section data, changes in channel geometry, and bankful flow travel times. A
reasonably accurate characterization of the channel system is needed to provide a sound basis
for routing of streamflow, sediment, and water quality constituents. Since measured cross
section data was not available for the Hunting Creek tributary, the channel cross section was
estimated from a field site visit. In HSPF, channel reaches are represented using Function
Tables (i.e. FTABLES). An FTABLE is a table of stage-volume-discharge-surface area
information that allows HSPF to determine the amount of channel storage and the routing of
streamflow through the channel reach system. For the Hunting Creek tributary channel, the
FTABLE was developed using a FORTRAN code which accepts the channel cross section, slope
of the flood plain, Manning's n and upstream/downstream elevations to calculate the components
of the FTABLE based on Manning's equation.
Land Use. Soils and Model Parameter Development
The watershed is covered with deciduous forest with steep-sided valleys at the lower elevations
and has relatively flat upland areas. The watershed is underlain by a thick sequence of
interbedded greenstone and sedimentary rocks known as the Catoctin Formation of Precambrian
age. In general, the soils derived from weathering of this formation belong to the Highfield
Series. These soils are medium textured, well developed and well-drained. A large part of the
watershed is mapped as rough and stony ground, and the thickest soils occur in the valley
bottoms (Katz et al. 1985).
Model parameter development is the process of estimating initial values of all the model
parameters needed to quantitatively define the important characteristics of the specific watershed
for which HSPF is being applied. These parameters include, or are related to soils
characteristics, topography and vegetation characteristics. For Hunting Creek watershed,
estimation of initial parameter values was derived from Segment 750 of the Chesapeake Bay
Watershed Model (Donigian et al, 1995). Since the forested land of Segment 750 was calibrated
for hydrology, sediment and water quality as part of the CBW modeling effort, using these
values as initial parameter values was considered to be a reasonable approach.
4.2.2 Young Woman's Creek, PA
Table 4.2 summarizes the available meteorologic, streamflow and water quality timeseries data
used in the simulation of Young Woman's Creek, PA. Figure 4.2 shows the locations of the
data stations in and around the watershed. Since Young Woman's Creek is contained within
Segment 60 of the CBW Model, much of the meteorologic database developed for the CBW
Model was used in this testing effort (Donigian et al., 1994). However, hourly precipitation and
49
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Table 4.2 Meteorologic, Streamflow and Water Quality Data for Simulation of Young Womans Creek, PA
PERIOD OF TIME
DATA TYPE LOCATION RECORD INTERVAL COMMENT
Ul
o
Precipitation
Renovo
Philipsburg
Air Temperature
Evaporation
Solar Radiation
Wind Movement
Dewpoint
Temperature
Streamflow
Water Quality
Snow Depth
Renovo, PA
Philipsburg, PA
Renovo, PA
Williamsport, PA
Williamsport, PA
Williamsport, PA
Binghamton, NY
Renovo, PA
Renovo, PA
Renovo, PA
1/84-12/91
1/84-12/91
1/80-03/86
9/86-12/91
1/84-12/91
1/84-12/91
1/84-12/91
1/84-12/91
12/64-9/93
5/65-3/95
1/80-12/91
Daily
Hourly
Daily(Max/Min)
Daily
Hourly
Hourly
Daily
Daily
Random
Daily
Disaggregated to hourly
Used in disaggregation
Missing data filled with'
CBW's Williamsport data
Data from Region 2 of CBW
(Donigian etal., 1994)
Data from Region 2 of CBW
Data from Region 2 of CBW
Data from Region 2 of CBW
USGS data
USGS data
NCDC data
-------
Location of Young Woman's Creek Watershed
Pennsylvania
Williamsport
Renovo
Renovo 6S
Philipsburg 8E
Harrisburg
Philadelphia
/:. .
?;'*YOUNG WOMANS
USGS Gage #01545600
LiAJL\J
WEST BRANCH SUSQUEHANNA RIVER
Figure 4.2 Young Womens Creek Watershed and Location of Meteorologic Stations
51
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daily max-min air temperature data closer to the site were collected, analyzed, and compared
with the available CBW data. As noted above for Hunting Creek, the HSPF simulation time
period for this study was limited to 1984 through 1991 to minimize the need for additional data
manipulation. Below we discuss the data collection and data base development efforts.
Hourly Precipitation Data
As noted above, development of reliable precipitation data is critical because it is the principal
driving force for the model simulation. Hourly precipitation data obtained from NCDC for the
Renovo 6S, PA station had incomplete records for.several months. Therefore this data was
considered incomplete and unreliable. On the other hand, the CBW database contained daily
precipitation data for Renovo, PA, a station located about ten miles north of Renovo 6S. The
database also had hourly precipitation data for the stations Philipsburg 8E and Sizerville, PA
(Figure 4.2). Since the Renovo station had daily data, the following two-step procedure was
followed to develop the needed complete hourly precipitation timeseries for the site:
1. The missing values in the Renovo data were filled with data from Philipsburg 8E.
2. METCMP was used to distribute the daily values from Renovo to hourly values based
on the hourly distribution of the Philipsburg data.
Air Temperature
Since the watershed is located in a mountainous region, snow is a significant component of the
hydrologic regime. In order to perform a reasonable snow simulation, development of reliable
air temperature data is the second most important (i.e. second to precipitation) of all the needed
meteorologic data. The daily maximum and minimum air temperature for the Renovo station
was obtained from the NCDC. Using METCMP, the daily max-min temperature were converted
to hourly air temperature, as described above for Hunting Creek. The ATEMP module in HSPF
performs the correction needed in air temperature values due to the elevation difference between
the average elevation of the watershed of 1400 ft, and the gage elevation of 660 ft.
Potential Evapotranspiration
Potential evapotranspiration from the CBW data base corresponding to Meteorologic Region 2
was used in the calibration (Donigian et al., 1994). The same procedures as described above
for Hunting Creek were used, with all the input meteorologic data from Williamsport, PA except
for dewpoint temperature which was collected at Binghamton, NY.
Other Meteorologic Data
The hourly wind speed data from the CBW data base for Meteorologic Region 2 was used. The
daily wind speed recorded at Williamsport, PA was distributed to hourly values as described
above. In addition, the hourly solar radiation, the daily cloud cover and dewpoint temperature
52
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data developed for the CBW, with the stations listed in Table 4.2, were used (Donigian et al.,
1994).
Flow. Water Quality and Atmospheric Deposition Data
Daily stream flow data was available for Young Womans creek from 1965 through 1993. Also,
monthly water quality data for nitrate and associated nitrogen species such as ammonia and
organic N, organic and inorganic P, BOD, DO, water temperature and sediment concentration
were also available from 1965 through 1994. Snow depth data were available from 1980
through 1991.
Atmospheric deposition data developed for the modeling of the Chesapeake Bay Watershed were
used in this effort. For the simulation of Young Woman's Creek, the data corresponding to
Segment 60 (West Branch Susquehanna basin) was obtained from the CBW data base. Wet and
dry nitrate, ammonia and organic N deposition data were available in pounds/day.
Characterization of the Channel System
As noted above, accurate characterization is needed to provide a sound basis for routing of
streamflow, sediment, and water quality constituents. However, measured cross section data
were not available for Young Womans creek. Thus, FTABLEs were developed from the
available rating curve data for the gage site (i.e. stage-discharge data), topographic maps, and
channel cross section data estimated from a field site visit.
Land Use. Soils and Model Parameter Development
Young Woman's Creek watershed is covered with deciduous forest. The watershed is underlain
by a sequence of sandstone, siltstone and claystone. The watershed area consists of soils of the
Dekalb-Lehew series. These soils are stony loam, moderately deep, well-drained and found on
the sides of the mountains and mountaintops. Additionally, these soils formed in material
derived from sandstone. The texture of the subsoil consists of stony sandy loam to sandy clay
loam.
Model parameter development is the process of estimating initial values of all the model
parameters needed to quantitatively define the important characteristics of the specific watershed
for which HSPF is being applied. These parameters include, or are related to soils
characteristics, topography and vegetation characteristics. For Young Womans creek, estimation
of initial parameter values was derived from Segment 60 of the Chesapeake Bay Watershed
Model (Donigian et al, 1995). The forested land of Segment 60 was calibrated for hydrology
sediment and water quality as part of the CBW Model effort. Thus, these parameter values were
considered to be reasonable initial values.
53
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4.3 HYDROLOGIC CALIBRATION
The hydrology calibration was performed using the HSPF Expert System (Lumb et al., 1994)
and following the general guidelines described in the HSPF Application Guide (Donigian et al.
1984). The Expert System for HSPF is a decision tool for hydrologic calibration that allows
users to interactively perform simulation runs, review model results in both tabular and graphical
form for flows and a variety of state variables, and receive advice on parameter adjustments to
improve the calibration. Model users can define acceptance criteria for a number of hydrologic
variables (e.g. total runoff volume, low flows, high flows, storm volumes, low flow recession,
etc.), and error statistics are provided to show users how well the criteria are satisfied. It is an
extremely powerful tool that helps to facilitate HSPF hydrologic calibration.
For the two test sites in this study, the HSPF Expert System was used to guide the calibration
with our primary focus on annual flow volumes, daily flow timeseries, and flow frequency
comparisons of simulated and observed values. Since both sites experience low temperatures
and significant snow accumulation, the snowmelt portions of HSPF were activated and model
results were compared to the available snow depth data. Unfortunately, the Expert System does
not yet provide calibration advice for snow simulation, so standard procedures based on past
experience were followed.
4.3.1 Hunting Creek, MD
A summary of the Hunting Creek hydrologic simulation and calibration is provided in Tables
4.3 and 4.4, and Figures 4.3 and 4.4. Table 4.3 shows the comparison of the simulated and
observed annual runoff volumes, while Table 4.4 shows the simulated hydrologic balance
components. Figure 4.3 is an example of the daily simulated and observed flows for 1990-91
while Figure 4.4 is the comparison of the cumulative flow frequency (flow-duration) curves,
simulated and observed. Complete simulation results are provided in Appendix A.
Based on these results, we characterize the Hunting Creek hydrologic calibration as follows:
a. The HSPF Expert System acceptance criteria for annual volumes, low and high flows,
low flow recession, and storm volumes, in the range of 10% to 15%, were satisfied,
indicating a reasonably good calibration.
b. The flow volumes in Table 4.3 indicate very good agreement for the mean annual values,
with generally good year-to-year match of the values, with some deviations.
c. The water balance components for the Hunting Creek Watershed (Table 4.4) appear to
be reasonable. As expected for a small forested watershed, the surface runoff is minimal
while the interflow and baseflow are the two primary outflow components.
54
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Table 4.3 Comparison of Annual Total Observed Flow vs Simulated Flow:
Hunting Creek Tributary Near Foxville, MD (USGS Gage No. 01640970)
YEAR Observed Simulated
Flow (in) Flow (in)
1984 34.86 41.23
1985 19.26 21.80
1986 17.33 15.33
1987 18.04 . 18.46
1988 17.84 18.33
1989 21.05 21.23
1990 22.78 22.05
1991 16.24 16.73
MEAN 20.92 21.97
Table 4.4 Simulated Hydrologic Balance for Hunting Creek Watershed
1984 1985 1986 1987 1988 1989 1990 1991 MEAN
Precipitation 66.30 47.71 38.02 43.29 42.11 46.84 51.87 39.93 47.01
(in)
Runoff (in)
Surface 4.94 0.80 0.51 0.94 2.76 2.01 0.70 0.42 1.63
Interflow 16.58 9.17 6.45 6.36 5.96 7.73 8.24 6.17 8.33
Baseflow 19.71 11.83 8.37 11.16 9.61 12.10 13.12 10.14 12.01
Total 41.23 21.80 15.33 18.46 18.33 21.83 22.05 16.73 21.97
Evapotranspiration (in)
33.31
8.63
9.65
6.75
Total 25.27 25.76 22.92 24.62 24.15 24.41 29.00 24.13 25.03
Potential
Intercep St
Upper Zone
Lower Zone
27.46
9.50
12.79
2.99
34.37
8.70
9.38
7.68
35.69
6.54
7.10
9.28
34.37
8.79
8.78
7.05
35.18
7.82
8.41
7.92
28.52
9.65
10.00
4.76
35.03
10.15
12.37
6.48
35.89
7.85
8.40
7.88
55
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" 2
ce
o_
0
100
90
80
70
60
50
10
30
20
10
niL.i mjii.«>L A/nL.j\A J..i , il.L> LlilJuJiJi.. tlm..
SIM FLOW
DBS FLOW
i i i r
i i i i i i
i f i i
JFMAMJJASONO
1990
F M A M J J A S 0 N D
1991
FIGURE 4.3 SIMULATED AND OBSERVED FLOW FOR HUNTING CREEK
TRIBUTARY NEAR FOXVILLE, MD, 1990-91
-------
Ol
i
10J
10
SimuI a ted
Observed
10
-1
10
-2
0.2 0.5 1
5
10
90
95
20 30 50 70 80
Percent of Time Flow Exceeded
FIGURE 4.4 FLOW FREQUENCY SIMULATION FOR HUNTING CREEK TRIBUTARY
NEAR FOXVILLE, MO
98 99 99.5
-------
d. The daily flow timeseries, Figure 4.3 and Appendix A, generally show good agreement
between the observed data and simulated values. However, the low flows below about
five cfs are somewhat under-simulated. We suspect that some of this difference may be
due to subsurface baseflow contributions from outside this small watershed.
e. The flow frequency curves in Figure 4.4 match quite well throughout the range of flows
exceeding about 40% - 50%. As noted above, below about five cfs there is a small
difference in the two frequency curves that is maintained down to extremely low flows.
f. As part of the hydrology calibration, snow simulation was performed and calibrated
against the observed snow depth data from Catoctin Mountain Park. Considering the
wide spatial variability in snow depth measurements, the results indicated a reasonable
agreement between the simulated and observed snow depth, (see Appendix A).
In summary, we feel the overall hydrology calibration for the Hunting Creek Watershed is
reasonable and shows good to very good agreement with the available observed data. Although
further improvement in low flows, storm volumes, and selected storm peaks is possible, and
should be pursued, the current hydrologic calibration provides a sound basis for testing the new
forest N simulation capabilities implemented in the AGCHEM module.
4.3.2 Young Womans Creek, PA
The hydrology calibration for Young Womans Creek was performed using the same procedures
as described above for Hunting Creek, i.e. the HSPF Expert System (Lumb et al., 1994) and
the general guidelines from the HSPF Application Guide (Donigian et al. 1984). This watershed
presented different problems than Hunting Creek because it is more than ten times larger, and
the available meteorologic data was much further from the watershed. Since the average
elevation of the watershed is about 1400 ft and the elevation of the rain gage is 610 ft, a
multiplication factor of 1.18 was used in the input rainfall timeseries to account for orographic
effects at the higher elevations (i.e. 18% increase), and isohyetal patterns. Also, a channel reach
was included in the simulation to account for travel time and storage effects within the channel
system.
Results of the Young Womans Creek hydrologic simulation and calibration is provided in Tables
4.5 and 4.6, and Figures 4.5 and 4.6. Table 4.5 shows the comparison of the simulated and
observed annual runoff volumes, while Table 4.6 shows the simulated hydrologic balance
components. Figure 4.5 is an example of the daily simulated and observed flows for 1988-89
while Figure 4.4 is the comparison of the cumulative flow frequency (flow-duration) curves,
simulated and observed. Complete simulation results are provided in Appendix B.
58
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Table 4.5 Comparison of Annual Total Observed Flow vs Simulated Flow:
Young Womans Creek Near Renovo, PA (USGS Gage No. 01545600)
YEAR Observed Simulated
Flow (in) Flow (in)
1984 28.58 31.14
1985 18.77 17.09
1986 23.66 21.06
1987 15.40 18.04
1988 13.39 13.55
1989 19.93 15.88
1990 26.94 28.76
1991 13.14 15.12
MEAN 19.98 20.08
Table 4.6 Simulated Hydrologic Balance for Young Womans Creek Watershed
1984 1985 1986 1987 1988 1989 1990 1991 MEAN
Precipitation 6Z.95 43.68 50.45 45.89 38.20 38.44 58.11 37.45 46.90
(in)
Runoff (in)
Surface 3.69 0.40 0.67 0.71 0.34 0.37 1.53 0.53 1.03
Interflow 12.28 6.74 9.35 7.00 5.03 6.89 12.49 7.20 8.37
Baseflow 15.17 9.95 11.04 10.33 8.18 8.62 14.75 7.39 10.68
Total 31.14 17.09 21.06 18.04 13.55 15.88 28.76 15.12 20.08
Evapotranspiration (in)
Potential 28.48 30.28 30.51 28.97 32.36 24.18 26.29 32.11 29.15
Intercep St 12.85 10.92 9.177 11.18 9.43 8.99 11.65 9.75 10.49
Upper Zone 11.14 7.44 10.91 10.64 -6.89 7.70 10.53 4.75 8.75
Lower Zone 4.17 9.71 9.05 6.26 9.41 6.54 3.88 0.71 7.47
Total 28.16 28.06 29.14 28.08 25.73 23.23 26.06 25.21 26.71
59
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jliAiJ.ui. AL^I .j>nvl. fct .. L tiAl. mm i. . A iLj j AH.A- u- ..^t .
uMjvLi .1. ... u u JHU..A
1,000
900
800
700
600
500
400
300
200
100
n i r
i i i i r
i i i i i i i i i i i r
SIM FLOW
OBS FLOW
JFMAMJJASOND
1988
JFMAMJJ
1989
SON
FIGURE 4.5 SIMULATED AND OBSERVED FLOW FOR YOUNG WOMAN'S CREEK
NEAR RENOVO, PA, 1988-89
-------
10'
S imuI a ted
Observed
10'
CO
l_i_
CJ>
10
10
-1
0.1 0.5 1 2 5 10 20 30 50 70 80 90 95 98 99 99.8
Percent of Time Flow Exceeded
FIGURE 1.6 FLOW FREQUENCY SIMULATION FOR YOUNG WOMAN'S CREEK NEAR RENOVO, PA
-------
The hydrologic calibration results for Young Womans Creek are very similar to those for
Hunting Creek in terms of the level of agreement between simulated and observed values. The
HSPF Expert System acceptance criteria are all satisfied in the 10% to 15% level, the annual
flow volumes in Table 4.5 show very good agreement, the hydrologic balance (Table 4.6) is
consistent with the expected forest hydrologic regime, the daily flow simulation in Figure 4.5
mimics the observed pattern, and the simulated flow frequency curve (Figure 4.6) provides a
very good representation of the observed curve. There appears to be some slight
undersimulation of low flows below about 10 cfs, similar to problems in Hunting Creek, which
could be due to channel banks effects, riparian vegetation, or baseflow contributions from
outside the basin. Further investigation and calibration could possibly improve these areas.
Snow simulation was also performed for Young Womans Creek, and calibrated against the
observed snow depth data at Renovo, PA. Since Renovo is at a much lower elevation than the
watershed, we calibrated the snow depths to be consistently higher than the observations (see
results in Appendix B). These results also provided more accurate winter and spring snowmelt
derived flow rates than would be expected with less snow pack.
In summary, although additional data and further calibration could improve the overall hydrology
simulation, we feel the results presented here are a sound basis for the forest N AGCHEM
testing described below.
4.4 AGCHEM TESTING FOR FOREST N CYCLING AND EXPORT
The objectives of testing the forest AGCHEM N enhancements on the small sites were
essentially identical to those for the Shenandoah watershed testing, i.e. to evaluate the model
enhancements and behavior of the algorithms, but with the additional calibration goals of
representing the observed N export concentrations at the watershed outlets. Also, model
parameterization was based on the same sources as discussed in Section 3.0, but with the
additional benefit of starting with the forest N parameters calibrated for the Shenandoah.
Below we present and discuss the model results for both Hunting Creek and Young Womans
Creek, concurrently, including the plant and soil N storages, and N exports. For convenience
and clarity, all the tables and figures are shown at the end of this section. Appendices D and
E include the HSPF User's Control Input (UCI) for the final model runs for Hunting Creek and
Young Womans Creek, respectively, showing the specific parameter values used to obtain these
results. As noted earlier, readers should refer to Section 2.0 or HSPF Version No. 11 User's
Manual (Bicknell et al., 1996) for parameter definitions.
Tables 4.7 and 4.8 are the summary tables of the AGCHEM simulation results for Hunting
Creek and Young Womans Creek, respectively, for the eight-year period from 1984 to 1991.
As noted earlier in Section 3.3, these tables include the following simulation results:
a. annual values for runoff, sediment loss, and N export for all N forms
62
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b. year-end storage values of various plant N pools
c. year-end storage values of all N forms in the soil layers
d. fluxes for atmospheric deposition, plant uptake, plant-to-litter, plant-to-soil, and litter-
to-soil returns
e. transformation fluxes for mineralization, denitrification, nitrification, immobilization,
and labile-to-refractory organic N conversion
f. sums and averages for the above information for the entire simulation period
Tables 4.9 and 4.10 show the initial and final N storages for the various plant and organic N
pools, along with the total and mean annual changes during the simulations for Hunting Creek
and Young Womans Creek, respectively.
Following these tables are the figures listed below which show the behavior of the various plant
and soil N pools, analogous to the figures discussed in Section 3.3 for the Shenandoah:
Figure 4.7 Simulated Forest AG, BG, Litter, and Total Plant N in Hunting Creek
Figure 4.8 Simulated Forest AG and BG Plant N in Hunting Creek, 1984-85
Figure 4.9 Simulated Labile, Refractory, Total Plant N and Total N Storage in Hunting
Creek
Figure 4.10 Simulated Monthly and Observed NO3-N, NH3-N, and Organic N
Concentrations in Hunting Creek Compared to Observed Data
Figure 4.11 Simulated Forest AG, BG, Litter, and Total Plant N in Young Womans Creek
Figure 4.12 Simulated Forest AG and BG Plant N in Young Womans Creek, 1984-85
Figure 4.13 Simulated Labile, Refractory, Total Plant N and Total N Storage in Young
Womans Creek
Figure 4.14 Simulated Monthly and Observed NO3-N, NH3-N, and Organic N
Concentrations in Young Womans Creek Compared to Observed Data
Figure 4.15 Simulated Monthly Mineralization Rates in Hunting Creek and Young
Womans Creek
These results from the small site testing on Hunting Creek and Young Womans Creek further
re-enforce the conclusions and recommendations derived from the Shenandoah simulations
discussed in Section 3.4. The N pools show similar patterns and behavior as noted earlier, and
demonstrate a reasonable representation of N cycling processes in forested watersheds. The lack
of appropriate data on forest N pools and storages is also an issue on these two small test sites,
indicating the possible need for more field data collection for proper parameterization when a
detailed simulation of this type is attempted.
Below we discuss some issues identified in this phase of the model testing that complement the
conclusions and recommendations provided earlier in Section 3.4:
a. Since the small watershed test sites are further north and generally at higher elevations
than the Shenandoah segment, the lower temperatures on these sites appeared to lead to
less mineralization, lower plant uptake, and generally less N cycling. The N pools still
63
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changed in the same direction as in the Shenandoah, but the changes were smaller. Both
mineralization and plant uptake (Tables 4.7 and 4.8) were near the lower end of the
expected range shown in Table 3.1, and the labile soil organic N still decreases but not
to the extent as in the Shenandoah. In the Shenandoah, labile N decreased about 45 Ib
N/ac/yr, or 4% annually; whereas in these sites the decrease is 10 and 17 Ib N/ac/yr, or
1.4% and 2.4% annually for Hunting Creek and Young Womans Creek, respectively.
The plant uptake was 50 to 60 Ib N/ac/yr and mineralization was 60 to 65 Ib N/ac/yr,
while these values were in the range of 90 to 95 Ib N/ac/yr in the Shenandoah.
b. For these sites the shallower soils and smaller tree heights, based on limited soil data and
field observations, indicated smaller soil and plant N storages than in the Shenandoah.
Also, using the Coweeta sites as typical templates (Johnson and Lindberg, 1992), we set
the AG and BG plant N pools to be about equal. Clearly, field data from these sites is
needed to better represent these N pools and their behavior as part of the forest N cycle.
c. The seasonal pattern of AG plant uptake, as shown in Figures 4.8 and 4.12, indicates the
same timing issues as discussed in Section 3.4 for the Shenandoah. The uptake pattern
shown from April through August is almost linear, whereas a more s-shaped curve would
be expected with the highest uptake rates during leaf-out in the spring and early summer.
It appears that uptake may be controlled and limited by the availability of the solution
inorganic N forms in our simulations, with most of the plant available N being generated
by mineralization during the growing season.
d. The overall changes in soil and plant N shown in Tables 4.9 and 4.10 for the eight-year
simulation period are consistent with the Shenandoah results. There is a net gain in plant
N that overcomes a net loss in soil N, to result in a small net gain in the total soil and
plant N, shown as the last line in the tables. As noted in Section 3.4, this net overall
gain is approximately equal to the difference between the atmospheric deposition and the
runoff flux. This confirms the N balance in the simulations, since leaching (i.e. losses
to deep groundwater) and volatilization are set to zero in our simulations, and
denitrification has been set at minimal levels (i.e. less than about 1 Ib N/ac/yr), the net
gain should be equal to the difference in inputs and outputs.
e. Figures 4.10 and 4.14 show the N export concentrations for these two sites. For the
Hunting Creek site (Figure 4.10), only NO3-N was measured, whereas some NH3-N and
organic N concentrations were also measured at Young Womans Creek (Figure 4.14).
The simulated concentrations are generally in the range of the observed data and within
the expected ranges for forested watersheds (Hunsaker et al., 1994). Additional data is
needed especially for NH3-N and organic N; the few organic N and NH3-N values in
Figure 4.14 indicate a wide range for organic N, which is consistent with the
simulations. The observed NH3-N values show no obvious pattern, but they fall within
the simulated range, except for 1991(see discussion below).
64
-------
f. In Hunting Creek the clear seasonal pattern in the observed NO3-N concentrations is not
well modeled; the timing problem noted in the Shenandoah results is evident here, but
it is not as obvious as in the Young Womans Creek results. The modeled increase in N
concentrations, primarily NO3-N, occurs in the late summer and fall before the increases
in the observations. As noted earlier, this pattern may be due to the plant uptake timing
and pattern, groundwater contributions from mineralization, and/or extreme low flow
conditions. It is clear that the low flow conditions contribute to the high concentrations
since the differences are the greatest in Hunting Creek in 1985-88 and 1991 when the
flow drops below 1 cfs for extended time periods during the summer and fall. A similar
condition occurs in Young Womans Creek in 1988 and 1991 when low flows of 2 to 3
cfs occurred. Fortunately, the export during these low flow periods is small, but further
investigation is needed to better represent the observed seasonal patterns in the
concentrations.
g. In Figure 4.15, the monthly mineralization rates show a reasonable pattern for Young
Womans Creek (bottom graph in Figure 4.15), similar to the Shenandoah results.
However, for Hunting Creek (top graph in Figure 4.15) the rates are erratic without any
obvious pattern. This could be due to problems in the temperature or possibly moisture
limitations, where fluxes and transformations are reduced at low moisture levels. The
reasons for this behavior are unknown at this time and are being investigated.
65
-------
Table 4.7 AGCHEM Simulation Results for Forest Land in Hunting Creek Watershed
Rainfall (in)
Runoff (in)
Surface
Interflow
Basef low
Total
Sediment Loss (t/a)
Nutrient Loss (Ib/a)
N03 Loss
Surface
Interflow
Basef low
Total
NH3 Loss
Surface
Interflow
Basef low
Sediment
Total
Labile ORGN
Surface
Interflow
Basef low
Sediment
Refrac ORGN
Surface
Interflow
Basef low
Sediment
Total ORGN Loss
Total N Loss (Ib/a)
STORAGES (Ib/ac)
AG Plant N
Litter N
BG Plant N Storage
Surface
Upper
Lower
1984
66.30
4.937
16.58
19.71
41.23
0.1380
0.1314
2.491
1.520
4.143
0.9126E-01
0.6315
0.1118
0.7998E-03
0.8354
0.6833E-01
0.7223
0.6318
0.1118
0.4757E-01
0.4733
0.5618
0.4425
3.059
8.037
353.6
27.99
50.26
299.1
100.4
1985
47.71
0.7990
9.171
11.83
21.80
0.2620E-02
0.2307E-01
2.047
1.096
3.166
0.2464E-01
0.3744
0.8196E-01
0.2721E-05
0.4810
0.2793E-01
0.4692
0.4592
0.5382E-03
0.1827E-01
0.3084
0.4252
0.2049E-02
1.711
5.358
363.3
27.51
50.50
300.6
100.3
1986
38.02
0.5110
6.454
8.366
15.33
0.1986E-02
0.1233E-01
2.323
1.041
3.377
0.2085E-01
0.4372
0.6866E-01
0.0000
0.5267
0.1895E-01
0.3309
0.3907
0.0000
0.1179E-01
0.2210
0.3747
0.0000
1.348
5.251
378.8
27.93
50.67
304.2
100.2
1987
43.29
0.9430
6.356
11.16
18.46
0.1689E-01
0.1245E-01
1.550
1.144
2.706
0.1444E-01
0.2867
0.7907E-01
0.7286E-04
0.3803
0.2247E-01
0.3001
0.4242
0.1581E-01
0.1322E-01
0.2073
0.4231
0.5349E-01
1.460
4.546
386.0
28.44
50.85
306.8
99.50
1988
42.11
2.759
5.960
9.614
18.33
0.1660
0.2167E-01
0.7023
0.9182
1.642
0.1784E-01
0.1301
0.6751E-01
0.7223E-03
0.2161
0.2741E-01
0.2481
0.3854
0.1668
0.1537E-01
0.1734
0.3993
0.5342
1.950
3.808
395.0
29.01
50.98
308.5
98.22
1989
46.84
2.005
7.731
12.10
21.83
0.8869E-01
0.3394E-01
1.152
0.7728
1.958
0.9719E-01
0.1740
0.6480E-01
0.4245E-03
0.3364
0.3359E-01
0.3240
0.4188
0.8987E-01
0.1802E-01
0.2280
0.4498
0.2759
1.838
4.133
396.5
29.38
51.16
310.3
96.82
1990
51.87
0.6980
8.236
13.12
22.05
0.5564E-02
0.1473E-01
1.630
0.8354
2.480
0.1915E-01
0.2596
0.7147E-01
0.2265E-04
0.3502
0.2332E-01
0.3954
0.3994
0.4828E-02
0.1194E-01
0.2764
0.4455
0.1406E-01
1.571
4.401
398.2
29.61
51.39
307.5
95.51
1991 SUM/AVER
39.93 47.01
0.4190 1.634
6.168 ' 8.332
10.14 12.01
16.73
0.1557E-02
0.1084E-01
1.872
0.7557
2.638
0.1088E-01
0.3716
0.5271E-01
0.2966E-05
0.4352
0.2042E-01
0.3411
0.3575
0.7370E-03
0.1023E-01
0.2367
0.4119
0.2135E-02
1.381
4.454
402.2
29.88
51.64
306.5
94.02
21.97
0.5266E-01
0.3255E-01
1.721
1.010
2.764
0.3703E-01
0.3331
0.7475E-01
0.2560E-03
0.4452
0.3030E-01
0.3914
0.4334
0.4880E-01
0.1830E-01
0.2656
0.4364
0.1655
1.790
4.998
384.2
28.72
50.93
305.4
98.12
Total AG, BG, Litter 831.3 842.2 861.8 871.6 881.6 884.2 882.2 884.2 867.4
Total Soil, Litter
& Plant N Storage 4356. 4359. 4362. 4366. 4369. 4375. 4379. 4383. 4369.
-------
Table 4.7 Continued
NH4-N
NH4-N
SOLN STORAGE
Surface
Upper
Interflow
Lower
GW
Total
ADS STORAGE
Surface
Upper
Lower
GW
Total
0.0000
0.5400E-01
0.2000E-02
0.6000E-02
0.1000E-02
0.6400E-01
0.2710
8.584
6.038
5.324
20.22
0.0000
0.4000E-01
0.1000E-02
0.6000E-02
0.1000E-02
0.4800E-01
0.2730
8.062
6.031
5.236
19.60
0.0000
0.5300E-01
0.1700E-01
0.6000E-02
0.3000E-02
0.8000E-01
0.2550
8.439
6.048
5.452
20.19
0.0000
0.4700E-01
0.5000E-02
0.6000E-02
0.2000E-02
0.6100E-01
0.2740
8.225
6.037
5.279
19.81
0.0000
0.4400E-01
0.4000E-02
0.5000E-02
0.3000E-02
0.5500E-01
0.2730
8.217
6.033
5.352
19.87
0.0000
0.4300E-01
0.2300E-01
0.5000E-02
0.2000E-02
0.7400E-01
0.2620
7.897
6.042
5.403
19.60
0.0000
0.6100E-01
0.3500E-01
0.5000E-02
0.2000E-02
0.1030
0.2650
8.365
6.029
5.151
19.81
0.0000
0.5500E-01
0.1400E-01
0.4000E-02
0.2000E-02
0.7500E-01
0.2580
8.328
6.022
5.258
19.86
0.0000
0.4962E-01
0.1262E-01
0.5375E-02
0.2000E-02
0.7000E-01
0.2664
8.265
6.035
5.307
19.87
N03/2-N STORAGE
Surface
Upper
Interflow
Lower
GW
Total
0.8000E-01
0.6820
0.1900E-01
0.1000E-02
0.3100E-01
0.8140
0.2000E-02
0.3310
0.4000E-02
0.3000E-02
0.8000E-02
0.3490
0.7700E-01
0.1420
0.6100E-01
0.1000E-02
0.8300E-01
0.3650
0.1000E-02
0.2920
0.3300E-01
0.1300E-01
0.3400E-01
0.3730
0.4200E-01
0.2450
0.1800E-01
0.1000E-02
0.4700E-01
0.3530
0.0000
0.1830
0.1520
0.5000E-01
0.1700E-01
0.4030
0.3000E-02
0.1970
0.1450
0.6000E-02
0.3300E-01
0.3840
0.1900E-01
0.2620
0.9800E-01
0.1000E-02
0.3600E-01
0.4160
0.2800E-01
0.2918
0.6625E-01
0.9500E-02
0.3612E-01
0.4321
Labile'ORGN(SOLN)
Surface
Upper
Interflow
Lower
GW
Total
0.7000E-02
0.5800E-01
0.2000E-02
0.2100E-01
0.1400E-01
0.1020
0.8000E-02
0.5700E-01
0.1000E-02
0.2000E-01
0.1300E-01
0.9900E-01
0.8000E-02
0.5400E-01
0.1200E-01
0.1900E-01
0.1300E-01
0.1060
0.8000E-02
0.5300E-01
0.6000E-02
0.1800E-01
0.1200E-01
0.9800E-01
0.9000E-02
0.5200E-01
0.4000E-02
0.1700E-01
0.1200E-01
0.9400E-01
0.9000E-02
0.5300E-01
0.3000E-01
0.1600E-01
0.1200E-01
0.1200
0.9000E-02
0.5300E-01
0.3000E-01
0.1600E-01
0.1100E-01
0.1200
0.1000E-01
0.5300E-01
0.1400E-01
0.1600E-01
0.1100E-01
0.1030
0.8500E-02
0.5412E-01
0.1237E-01
0.1788E-01
0.1225E-01
0.1052
Labile ORGN(ADS)
Refrac
Refrac
Surface
Upper
Lower
GW
Total
ORGN(SOLN)
Surface
Upper
Interflow
Lower
GW
Total
ORGN(ADS)
Surface
Upper
Lower
GW
Total
51.38
405.1
144.2
96.64
697.3
0.5000E-02
0.3800E-01
0.1000E-02
0.1500E-01
0.1300E-01
0.7200E-01
197.3
1505.
602.8
501.2
2806.
53.66
399.0
136.8
93.33
682.9
0.5000E-02
0.3800E-01
0.1000E-02
0.1500E-01
0.1300E-01
0.7100E-01
195.8
1510.
605.4
502.5
2814.
57.00
378.9
131.1
89.87
656.9
0.5000E-02
0.3800E-01
0.8000E-02
0.1500E-01
0.1300E-01
0.7900E-01
194.7
1516.
608.0
503.7
2823.
59.08
372.6
125.4
86.80
643.9
0.5000E-02
0.3800E-01
0.4000E-02
0.1500E-01
0.1300E-01
0.7500E-01
193.1
1521.
610.5
504.8
2830.
61.87
365.0
119.9
83.72
630.5
0.5000E-02
0.3800E-01
0.3000E-02
0.1500E-01
0.1300E-01
0.7400E-01
191.5
1526.
612.9
505.9
2837.
63.71
367.8
115.4
80.94
627.8
0.5000E-02
0.3800E-01
0.2100E-01
0.1500E-01
0.1300E-01
0.9200E-01
189.8
1531.
615.2
507.0
2843.
65.16
371.3
111.9
78.42
626.8
0.5000E-02
0.3800E-01
0.2100E-01
0.1500E-01
0.1300E-01
0.9200E-01
188.3
1536.
617.5
508.0
2850.
67.11
370.3
108.6
75.72
621.8
0.5000E-02
0.3900E-01
0.1000E-01
0.1500E-01
0.1300E-01
0.8100E-01
187.0
1541.
619.7
508.9
2856.
59.87
378.8
124.2
85.68
648.5
0.5000E-02
0.3813E-01
0.8625E-02
0.1500E-01
0.1300E-01
0.7950E-01
192.2
1523.
611.5
505.3
2832.
-------
OO
Table 4.7 Concluded
FLUXES (Ib/ac)
Atmos Dep(lb/ac)
NH3-N
N03-N
ORGN
Plant Uptake
Above Ground
NH3 Uptake
N03 Uptake
Below Ground
NH3 Uptake
N03 Uptake
Above Ground Plant
N to Litter
Litter N Return
to Labile ORGN
Surface
Upper
Total
to Refrac ORGN
Surface
Upper
Total
BG Plant N Ret
to Labile ORGN
Surface
Upper
Lower
Total
to Refrac ORGN
Surface
Upper
Lower
Total
L/R ORGN Conversion
LORGN Mineralization
Denitrification
NH3 Nitrification
NH3 Immobilization
N03 Immobilization
2.434
7.739
0.6068
17.52
5.546
1.971
6.932
0.6070
17.99
5.990
1.875
6.840
0.6070
1.871
6.777
0.6070
1.767
6.527
0.6068
2.315
7.305
0.6070
2.235
7.390
0.6070
18.74
19.14
19.58
19.68
19.76
6.765
5.712
5.748
4.873
5.058
1.752
6.621
0.6070
19.96
5.192
2.028
7.016
0.6069
17.29
3.816
17.89
4.261
23.29
4.428
22.27
4.681
28.83
5.447
29.26
6.338
21.81
4.464
23.36
4.833
23.94
4.632
23.56
4.837
17.31
3.887
18.87
3.887
16.60
4.850
16.88
5.007
20.26
3.681
19.05
4.371
21.17
4.401
21.39
4.777
19.05
5.902
12.65
18.55
0.3107
0.6657
0.9763
5.582
11.96
17.54
0.2938
0.6296
0.9234
5.541
11.87
17.41
0.2916
0.6249
0.9165
5.630
12.06
17.70
0.2963
0.6350
0.9313
5.747
12.31
18.06
0.3025
0.6481
0.9506
5.838
12.51
18.35
0.3073
0.6584
0.9657
5.904
12.65
18.55
0.3107
0.6658
0.9766
5.953
12.76
18.71
0.3133
0.6713
0.9846
5.762
12.35
18.11
0.3033
0.6499
0.9531
0.0000
13.20
8.098
21.30
0.0000
0.6948
0.4262
1.121
0.0000
15.94
8.075
24.01
0.0000
0.8388
0.4250
1.264
0.0000
22.32
8.067
30.39
0.0000
1.175
0.4246
1.599
0.0000
16.75
8.023
24.78
0.0000
0.8817
0.4223
1.304
0.0000
18.50
7.976
26.47
0.0000
0.9736
0.4198
1.393
0.0000
13.19
7.821
21.02
0.0000
0.6944
0.4117
1.106
0.0000
16.78
7.715
24.50
0.0000
0.8833
0.4060
1.289
0.0000
16.73
7.612
24.34
0.0000
0.8805
0.4006
1.281
0.0000
16.68
7.923
24.60
0.0000
0.8778
0.4170
1.295
5.610
59.49
1.426
12.54
15.99
7.523
68.94
1.330
10.82
14.68
4.616
85.88
1.167
15.33
13.19
5.828
67.28
1.123
10.69
13.31
4.331
69.22
1.376
10.16
13.06
4.217
53.81
0.4453
6.976
12.88
4.053
56.95
2.004
12.05
13.08
5.114
61.23
0.6992
10.11
13.10
5.307
65.35
1.196
11.08
13.66
5.124
-------
Table 4.8 AGCHEM Simulation Results for Forest Land in Young Womans Creek Watershed
Rainfall (in)
Runoff (in)
Surface
Interflow
Basef low
Total
Sediment Loss (t/a)
Nutrient Loss (Ib/a)
N03 Loss
Surface
Interflow
Basef low
Total
NH3 Loss
Surface
Interflow
Basef low
Sediment
Total
Labile ORGN
Surface
Interflow
Basef low
Sediment
Refrac ORGN
Surface
Interflow
Basef low
Sediment
Total ORGN Loss
Total N Loss (Ib/a)
STORAGES (Ib/ac)
AG Plant N
Litter N
BG Plant N Storage
Surface
Upper
Lower
1984
62.95
3.692
12.28
15.17
31.14
0.2090
0.1128
0.6220
1.017
1.752
0.2365E-01
0.3693E-01
0.3923E-01
0.1042E-02
0.1008
0.5052E-01
0.6095
0.5159
0.1816
0.2756E-01
0.3043
0.3502
0.7400
2.780
4.632
363.6
28.34
50.21
225.1
90.67
1985
43.68
0.4000
6.742
9.952
17.09
0.1584E-01
0.9087E-02
0.5198
1.093
1.622
0.3690E-02
0.2301E-01
0.4051E-01
0.7224E-04
0.6728E-01
0.2071E-01
0.3736
0.4157
0.1315E-01
0.1131E-01
0.1865
0.2931
0.5342E-01
1.368
3.057
377.4
28.21
50.32
232.1
96.34
1986
50.45
0.6710
9.347
11.04
21.06
0.9355E-02
0.3646E-01
1.000
0.8825
1.919
0.1278E-01
0.4105E-01
0.3356E-01
0.3647E-04
0.8743E-01
0.3376E-01
0.4933
0.4234
0.6480E-02
0.1846E-01
0.2465
0.3104
0.2676E-01
1.559
3.566
386.2
28.56
50.54
237.5
98.65
1987
45.89
0.7060
7.004
10.33
18.04
0.1545E-01
0.3652E-01
0.5889
0.7502
1.376
0.2837E-01
0.3107E-01
0.2881E-01
0.7862E-04
0.8833E-01
0.2480E-01
0.3587
0.4019
0.1164E-01
0.1344E-01
0.1781
0.3056
0.4736E-01
1.341
2.805
391.5
28.94
50.73
243.2
98.77
1988
38.20
0.3380
5.030
8.181
13.55
0.6986E-02
0.1142E-01
0.6412
0.8342
1.487
0.9774E-02
0.2995E-01
0.2980E-01
0.2822E-04
0.6955E-01
0.1740E-01
0.2846
0.3479
0.4918E-02
0.9372E-02
0.1408
0.2741
0.1993E-01
1.099
2.655
401.5
29.50
50.88
251.0
97.93
1989
38.44
0.3650
6.890
8.624
15.88
0.8499E-02
0.1630E-01
0.5320
0.7926
1.341
0.8115E-02
0.2233E-01
0.2758E-01
0.4059E-04
0.5807E-01
0.1749E-01
0.3659
0.3387
0.6566E-02
0.9111E-02
0.1828
0.2775
0.2581E-01
1.224
2.623
405.9
29.97
51.03
258.0
95.93
1990
58.11
1.532
12.49
14.75
28.76
0.7520E-01
0.6709E-01
0.8029
0.7142
1.584
0.1603E-01
0.4878E-01
0.2764E-01
0.4206E-03
0.9287E-01
0.4061E-01
0.6239
0.4103
0.6173E-01
0.2088E-01
0.3117
0.3492
0.2368
2.055
3.732
406.9
30.22
51.20
262.8
93.25
1991 SUM/AVER
37.45 46.90
0.5250
7.198
7.393
15.12
0.8054E-02
0.1315E-01
0.7830
0.6679
1.464
0.1461E-01
0.5649E-01
0.2722E-01
0.3083E-04
0.9836E-01
0.2676E-01
0.4108
0.3115
0.5343E-02
0.1420E-01
0.2038
0.2739
0.2142E-01
1.268
2.830
421.4
30.88
51.30
273.4
90.81
1.029
8.372
10.68
20.08
0.4355E-01
0.3785E-01
0.6862
0.8440
1.568
0.1463E-01
0.3620E-01
0.3179E-01
0.2187E-03
0.8284E-01
0.2901E-01
0.4400
0.3957
0.3643E-01
0.1554E-01
0.2193
0.3043
0.1464
1.587
3.237
394.3
29.33
50.77
247.9
95.29
Total AG, BG, Litter 757.9 784.4 801.4 813.2 830.9 840.9 844.3 867.8 817.6
Total Soil, Litter
& Plant N Storage 4253. 4261. 4269. 4277. 4285. 4293. 4301. 4307. 4281.
-------
Table 4.8 Continued
NH4-N SOLN Storage
Surface
Upper
Interflow
Lower
GW
Total
NH4-N ADS Storage
Surface
Upper
Lower
GW
Total
N03/2-N Storage
Surface
Upper
Interflow
Lower
GW
Total
Labile ORGN(SOLN)
Surface
Upper
Interflow
-J Lower
0 GW
Total
Labile ORGN(ADS)
Surface
Upper
Lower
GW
Total
Refrac ORGN(SOLN)
Surface
Upper
Interflow
Lower
GW
Total
Refrac ORGN(ADS)
Surface
Upper
Lower
GW
Total
0.0000
0.2000E-01
0.7000E-02
0.1900E-01
0.2000E-02
0.4800E-01
0.2410
7.050
6.318
4.957
18.57
0.2700E-01
0.6900E-01
0.4400E-01
0.2100E-01
0.5700E-01
0.2180
0.1200E-01
0.1020
0.3700E-01
0.3000E-01
0.2400E-01
0.2040
47.31
406.0
120.0
96.69
670.1
0.7000E-02
0.5000E-01
0.1800E-01
0.2000E-01
0.1700E-01
0.1120
195.6
1506.
603.1
501.4
2806.
0.0000
0.1200E-01
0.0000
0.1300E-01
0.1000E-02
0.2700E-01
0.2530
6.980
6.271
4.980
18.48
0.3000E-02
0.3200
0.3000E-02
0.1700E-01
0.4400E-01
0.3870
0.1200E-01
0.1010
0.2000E-02
0.2500E-01
0.2300E-01
0.1630
46.99
405.4
98.49
93.15
644.0
0.6000E-02
0.5000E-01
0.1000E-02
0.2000E-01
0.1700E-01
0.9500E-01
192.7
1512.
605.8
502.8
2813.
0.0000
0.1000E-01
0.1000E-02
0.1000E-01
0.1000E-02
0.2200E-01
0.2490
6.948
6.242
4.963
18.40
0.1000E-01
0.3180
0.2000E-01
0.9000E-02
0.3400E-01
0.3910
0.1200E-01
0.1020
0.8000E-02
0.2100E-01
0.2200E-01
0.1650
46.68
408.3
83.71
89.99
628.7
0.6000E-02
0.5100E-01
0.4000E-02
0.2000E-01
0.1700E-01
0.9800E-01
190.0
1517.
608.2
504.2
2820.
0.0000
0.1800E-01
0.1000E-02
0.8000E-02
0.2000E-02
0.2800E-01
0.2600
7.063
6.227
4.994
18.54
0.1050
0.2280
0.7000E-02
0.6000E-02
0.5300E-01
0.3990
0.1200E-01
0.1030
0.4000E-02
0.1800E-01
0.2200E-01
0.1580
46.50
412.4
73.12
86.99
619.0
0.6000E-02
0.5100E-01
0.2000E-02
0.2000E-01
0.1700E-01
0.9600E-01
187.3
1523.
610.4
505.4
2826.
0.0000
0.1700E-01
0.0000
0.7000E-02
0.2000E-02
0.2700E-01
0.2670
7.073
6.229
5.119
18.69
0.6200E-01
0.3670
0.1000E-01
0.6000E-02
0.7400E-01
0.5180
0.1200E-01
0.1010
0.3000E-02
0.1600E-01
0.2100E-01
0.1530
47.42
405.6
64.67
83.82
601.6
0.6000E-02
0.5100E-01
0.1000E-02
0.2000E-01
0.1700E-01
0.9600E-01
185.0
1529.
612.3
506.6
2833.
0.0000
0.6000E-02
0.0000
0.6000E-02
0.2000E-02
0.1300E-01
0.3110
6.910
6.223
5.128
18.57
0.5270
0.2000E-02
0.0000
0.4000E-02
0.6500E-01
0.5990
0.1200E-01
0.1020
0.0000
0.1500E-01
0.2000E-01
0.1490
48.37
406.2
58.54
80.94
594.1
0.6000E-02
0.5100E-01
0.0000
0.2000E-01
0.1700E-01
0.9500E-01
183.0
1534.
614.1
507.9
2839.
0.0000
0.2100E-01
0.5000E-02
0.4000E-02
0.1000E-02
0.3100E-01
0.2520
7.063
6.190
4.919
18.42
0.1900E-01
0.2090
0.3200E-01
0.4000E-02
0.2800E-01
0.2930
0.1100E-01
0.1040
0.2400E-01
0.1400E-01
0.2000E-01
0.1730
45.56
415.2
54.52
78.47
593.8
0.6000E-02
0.5100E-01
0.1200E-01
0.2100E-01
0.1700E-01
0.1070
179.2
1540.
616.0
508.9
2844.
0.0000
0.2600E-01
0.0000
0.5000E-02
0.4000E-02
0.3500E-01
0.2700
7.217
6.208
5.297
18.99
0.3000E-02
0.3940
0.2000E-02
0.5000E-02
0.1700
0.5750
0.1200E-01
0.9900E-01
0.1000E-02
0.1300E-01
0.1900E-01
0.1430
46.72
395.0
50.21
75.34
567.3
0.6000E-02
0.5200E-01
0.1000E-02
0.2100E-01
0.1700E-01
0.9600E-01
176.9
1548.
617.8
510.0
2853.
0.0000
0.1625E-01
0.1750E-02
0.9000E-02
0.1875E-02
0.2887E-01
0.2629
7.038
6.239
5.045
18.58
0.9450E-01
0.2384
0.1475E-01
0.9000E-02
0.6562E-01
0.4225
0.1188E-01
0.1018
0.9875E-02
0.1900E-01
0.2137E-01
0.1635
46.94
406.8
75.41
85.68
614.8
0.6125E-02
0.5087E-01
0.4875E-02
0.2025E-01
0.1700E-01
0.9937E-01
186.2
1526.
611.0
505.9
2829.
-------
Table 4.8 Concluded
Atmos Dep(lb/ac)
NH3-N
N03-N
ORGN
Plant Uptake
Above Ground
NH3 Uptake
N03 Uptake
Below Ground
NH3 Uptake
N03 Uptake
Above Ground Plant
M to Litter
Litter N Return
to Labile ORGN
Surface
Upper
Total
to Refrac ORGN
Surface
Upper
Total
8G Plant N Ret
to Labile ORGN
Surface
Upper
Lower
Total
to Refrac ORGN
Surface
Upper
Lower
Total
L/R ORGN Conversion
LORGN Mineralization
Denitrification
NH3 Nitrification
NH3 Immobilization
N03 Immobilization
2.574
9.127
0.6068
17.93
5.809
2.101
8.393
0.6070
18.64
5.572
2.361
8.786
0.6070
2.238
8.481
0.6070
1.955
8.048
0.6068
2.289
8.526
0.6070
2.420
8.925
0.6070
19.13
19.40
19.90
20.13
20.18
4.881
4.561
5.182
4.422
4.081
1.698
7.696
0.6070
20.83
6.015
2.204
8.498
0.6069
25.39
6.107
25.95
7.713
27.56
4.959
27.48
5.738
23.35
4.518
22.38
4.842
20.32
4.443
20.78
4.568
24.88
4.992
25.06
5.566
20.09
4.424
21.28
4.316
16.92
4.229
17.18
4.498
26.08
9.311
26.28
12.30
23.07
5.373
23.30
6.193
19.52
5.923
12.69
18.62
0.3117
0.6680
0.9798
5.672
12.16
17.83
0.2986
0.6398
0.9383
5.676
12.16
17.84
0.2987
0.6402
0.9389
5.748
12.32
18.07
0.3025
0.6483
0.9508
5.846
12.53
18.37
0.3077
0.6593
0.9670
5.942
12.73
18.67
0.3127
.0.6701
0.9829
6.023
12.91
18.93
0.3170
0.6793
0.9963
6.098
13.07
19.16
0.3209
0.6877
1.009
5.866
12.57
18.44
0.3087
0.6616
0.9704
0.0000
7.887
8.917
16.80
0.0000
0.4151
0.4693
0.8844
0.0000
9.679
9.715
19.39
0.0000
0.5094
0.5113
1.021
0.0000
8.271
10.12
18.39
0.0000
0.4353
0.5324
0.9678
0.0000
8.079
10.22
18.30
0.0000
0.4252
0.5382
0.9634
0.0000
12.13
10.22
22.35
0.0000
0.6385
0.5380
1.176
0.0000
9.390
10.03
19.42
0.0000
0.4942
0.5281
1.022
0.0000
8.659
9.794
18.45
0.0000
0.4557
0.5155
0.9712
0.0000
19.25
9.535
28.79
0.0000
1.013
0.5019
1.515
0.0000
10.42
9.819
20.24
0.0000
0.5483
0.5168
1.065
5.065
74.00
0.6212
10.06
12.28
3.127
70.94
0.5266
7.312
10.73
2.690
58.84
0.3971
5.098
10.37
2.203
53.48
0.3485
4.161
10.22
1.899
63.71
0.6057
6.596
8.916
1.874
51.17
0.4000
3.575
8.586
1.540
44.22
0.3162
3.027
9.547
1.630
77.53
1.267
18.91
7.275
1.984
61.74
0.5603
7.342
9.740
2.118
-------
Table 4.9 Simulated Changes in Forest N Pools from 1984 to 1991 for Hunting Creek
INITIAL FINAL TOTAL MEAN ANNUAL
STORAGE STORAGE CHANGE CHANGE
Aboveground Plant N
Litter N
Belowground Plant N
Total Plant N
Labile Soil N
Refractory Soil N
Total Soil N
TOTAL N
Table 4. 10 Simulated
Creek
Aboveground Plant N
Litter N
Belowground Plant N
Total Plant N
Labile Soil N
Refractory Soil N
350
30
450
830
700
2800
3500
4330
\i\J Ml (Us)
402
30
452
884
662
2856
3478
4362
52
0
2
54
-78
56
-22
32
Changes in Forest N Pools from 1984 to
INITIAL
STORAGE
350
30
350
730
700
2800
FINAL
STORAGE
- (Ib N/ac)
421
31
416
868
567
2853
TOTAL
CHANGE
71
1
66
138
-138
53
^iu Liia\,iyij
6.5
0.0
0.3
6.8
-9.8
7.0
-2.8
4.0
1991 for Young Womans
MEAN ANNUAL
CHANGE
(Ib N/ac/yr)
8.9
0.1
8.3
17.3
-16.6
6.6
Total Soil N
TOTAL N
3500
4230
3420
4288
-80
58
-10.0
7.3
72
-------
O
-«£
O
CO
40
30
20
10
0
1.000
900
800
700
600
500
400
300
AG PLANT N
BG PLANT N
1984 1985 1986 1987 1988 1989 1990
FIGURE 4.7 SIMULATED FOREST AG, BG, LITTER AND TOTAL PLANT N IN
HUNTING CREEK WATERSHED
1991
-------
500
450
400
400
395
< 390
CD
~| 385
£ 380
°~ 375
1 37°
£ 365
en
* 360
355
350
I I I I I I I T T I I I I \ I I
I I
I I
I I l
J F M
AMJJASONDJFMAMJJ/
1984 1985
FIGURE 4.8 SIMULATED FOREST ABOVE GROUND AND BELOW GROUND PLANT N IN
HUNTING CREEK WATERSHED. 1984-85
S 0 N D
-------
4500
4300
4100
3900
3700
3500
3300
3100
2900
2700
2500
900
870
TOTAL N
REFRACTORY N
o
03
0=
O
810
780
750
720
690
660
630
600
1984 1985 1986 1987 1988 1989 . 1990 1991
FIGURE 4.9 SIMULATED LABILE, REFRACTORY, TOTAL PLANT N AND TOTAL N STORAGE IN
HUNTING CREEK WATERSHED
-------
0.3
'0.15
CO
z
o
-«£
oe
0
5.0
4.5
4.0
3.5
SIM N03-N
DBS N03-N
SIM ORGN
1984 1985 1986 1987 1988 1989 1990 1991
FIGURE 4.10 SIMULATED MONTHLY N03-N. ORGANIC N AND NH3-N CONCENTRATIONS IN
HUNTING CREEK WATERSHED COMPARED TO OBSERVED DATA
-------
CJ
CO
40
30
20
10
0
1.000
900
800
700
600
500
400
300
AG PLANT N
BG PLANT N
TOTAL PLANT N
1984 1985 1986 1987 1988 1989 1990
FIGURE 4.11 SIMULATED FOREST AG, BG, LITTER AND TOTAL PLANT N
YOUNG WOMANS CREEK WATERSHED
1991
-------
400
--J
00
o
CD
I O.
L>J
CO
375
350
400
395
390
385
380
375
370
365
360
355
350
I I I I
i i
I i I i
i i i
i i i i i i i i i i i i i i i i i i i i i i
JFMAMJJASOND
1984
JFMAMJJASOND
1985
FIGURE 4.12 SIMULATED FOREST ABOVE GROUND AND BELOW GROUND PLANT N IN
YOUNG WOMANS CREEK WATERSHED, 1984-85
-------
VO
«
^
o
CD
'
LU
DC
0
1
LO
4350
4190
4030
3870
3710
3550
3390
3230
3070
2910
2750
1 ,000
950
900
850
800
750
700
b50
bOO
550
500
TOTAL N
-
-
-
-
REFRACTORY N
LABILE N
IOTAL PLANT N
^__ ___^- S~~-
..^
^~
^^
" --. . r-
~~~~~~~ N_ _______ ___
1 1 1 1 1 1 1
1984 1985 1986 1987 1988 1989
FIGURE 4.13 SIMULATED LABILE, REFRACTORY, TOTAL PLANT N AND
IN YOUNG WOMANS CREEK WATERSHED
1990 1991
TOTAL N STORAGE
-------
0.1
oo
o
"0.05
0
5.0
4.5
4.0
3.5
3.0
2'5
2.0
1.5
1.0
0.5
0
SIM N03-N
OBS N03-N
SIM ORGN
OBS ORCN
1984 1985 1986 1987 1988 1989 1990 1991
FIGURE 4.14 SIMULATED MONTHLY N03-N, ORGANIC N AND NH3-N CONCENTRATIONS FOR
YOUNG WOMANS CREEK WATERSHED COMPARED TO OBSERVED DATA
-------
15
7.5
00
0
30
27
24
21
18
15
12
9
6
3
0
1954
1985
1986
1987
1988
1989
1990
1991
FIGURE 4.15 SIMULATED FOREST MONTHLY MINERALIZATION RATE FOR HUNTING CREEK
(TOP GRAPH) AND YOUNG WOMANS CREEK {BOTTOM GRAPH) WATERSHEDS
-------
SECTION 5.0
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Lumb, A.M., R.B. McCammon, and J.L. Kittle, Jr. 1994. Users Manual for an Expert System
(HSPEXP) for Calibration of the Hydrological Simulation Program - Fortran. Water-
Resources Investigations Report 94-4168, U.S. Geological Survey, Reston, VA. 102 p.
83
-------
Lumb, A.M. and J.L. Kittle, Jr. 1995. Users Manual for METCMP, A Computer Program for
Interactive Computation of Meteorologic Time Series. Water-Resources Investigation Report
95-xxxx, DRAFT REPORT. U.S. Geological Survey, Reston, VA. 88 p.
Miller, R.W. and R.L. Donohue. 1990. Soils: An Introduction to Soils and Plant Growth.
6th Edition. Prentice Hall, Englewood Cliffs, NJ. p 264.
Pastor, J. and W.M. Post. 1986. Influence of Climate, Soil Moisture, and Succession on Forest
Carbon and Nitrogen Cycles. Biogeochemistry, 2:3-27.
Penman, H.L. 1948. Natural Evaporation from Open Water, Bare Soil, and Grass. Proceedings
of the Royal Society of London, Ser A, Vol. 193, No. 1032, pp. 120-145.
Reddy, K.R., R. Khaleel, M.R. Overcash, and P.W. Westerman. 1979. A Nonpoint Source
Model for Land Areas Receiving Animal Waste: II. Ammonia Volatilization. Trans. ASAE,
22(6): 1398-1405.
Rice, K.C., M.M. Kennedy, O.P Bricker, and C.A. Donnelly. 1993. Data on the Quantity and
Chemical Quality of Precipitation, Catoctin Mountain, North-Central Maryland, 1982-91.
U.S. Geological Survey, Open-File Report 93-169. Towson, MD. 46 p.
Rice, K.C. and O.P Bricker. 1995. Seasonal Cycles of Dissolved Constituents in Streamwater
in Two Forested Catchments in the Mid-Atlantic Region of the Eastern USA. J. Hydrol.
170:137-158
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Groundwater Quality and Farm Profitability. R.F. Follett, D.R. Keeney, and R.M. Cruse
(eds.). Soil Science Society of America, Inc.
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File: \910317\reptforn.wp
84
-------
APPENDICES
Appendix A. Hunting Creek Hydrology Simulation Results
Appendix B. Young Womans Creek Hydrology Simulation Results
Appendix C. Shenandoah Segment 190 UCI
Appendix D. Hunting Creek UCI
Appendix E. Young Womans Creek UCI
85
-------
Appendix A. Hunting Creek Hydrology Simulation Results
Flow Frequency Simulation for Hunting Creek Tributary Near Foxville, MD
Simulated and Observed Flow for Hunting Creek Tributary Near Foxville, MD (1984-87)
Simulated and Observed Flow for Hunting Creek Tributary Near Foxville, MD (1988-91)
Simulated and Observed Snow Depth in Hunting Creek Watershed (1984-87)
Simulated and Observed Snow Depth in Hunting Creek Watershed (1988-91)
86
-------
00
10°
10
10
-1
10
-2
S imuI a ted
Observed
0.2 0.5 1 2 5 10 20 30 50 70 80 90 95
Percent of Time Flow Exceeded
FLOW FREQUENCY SIMULATION FOR HUNTING CREEK TRIBUTARY NEAR FOXVILLE, MD
98 99 99.5
-------
00
00
cc:
CL-
360
320
280
210
200
160
Jill
400 IIIIIIII
SIM FLOW
OBS FLOW
JFMAMJJASOND
- i i i
JFMAMJJASOND
1984
1985
JFMAMJJASOND
1986
JFMAMJJASOND
1987
SIMULATED AND OBSERVED FLOW FOR HUNTING CREEK TRIBUTARY
NEAR FOXVILLE, MD, 1984-87
-------
oo
VO
4
2
0
500
450
400
350
300
250
200
150
100
50
J.uJ iJ
SIM FLOW
DBS FLOW
JitWr^k^
.1 U-.J tli/i
JFMAMJJASONDJFMAMJJASOND
1988
1989
JFMAMJJASOND
1990
JFMAMJJASOND
199
SIMULATED AND OBSERVED FLOW FOR HUNTING CREEK TRIBUTARY
NEAR FQXVILLE, MD, 1988-91
-------
z 6
" 3
O-
0
20
18
16
14
~ 12
3:
£ 10
*
o
S 8
LlilJlUJili
llu.
.i i-iMliJ ..I. l.iLlLiJiJ*..tiii kliili.jL
SIM SNOW DEPTH
OBS SNOW DEPTH
i i i i i i
I I I I I I 11* L!
J F M A M J J A S 0 N OU F M A M J J A S 0 N D
1984
1985
JFMAMJJASONDJFMAMJJASOND
1986
1987
SIMULATED AND OBSERVED SNOW DEPTH IN HUNTING CREEK WATERSHED, 1984-87
-------
o
CO
4
2
1. -
0
20
18
16
14
12
10
8
6
4
2
1 1 1 1 1 1 1 1 I 1 1 1 1 1
'
1 1
Jd I L
il iL
1 1 II"
Llll.Lllll.Jl.^llni.lUjl.lUllL.lj.lLLlLil.Li.lllLl
1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
SIM SNOW DEPTH
DBS SNOW DEPTH
-
_
~
~
'
"
i
|
n
J
-
1
1
' 11 '
;|l ;
^5r. ........ .SI.!.'
0
i
1
i
i
!
,
1 I i i I t i I I
JFMAMJJASONDJFMAMJJASON
(1
['
,y
D
,
J F M
-
1 1 1 1 1 1 1 1 b
A M J J A S 0 N D
!
1
\
>l !'l 1 I 1 1 1 1 1 1 H I
JFMAMJJASOND
1988
1989
1990
1991
SIMULATED AND OBSERVED SNOW DEPTH IN HUNTING CREEK WATERSHED, 1988-91
-------
Appendix B. Young Womans Creek Hydrology Simulation Results
Flow Frequency Simulation for Young Woman's Creek Near Renovo, PA
Simulated and Observed Flow for Young Womans's Creek Near Renovo, PA (1984-87)
Simulated and Observed Flow for Young Womans's Creek Near Renovo, PA (1988-91)
Simulated and Observed Snow Depth in Young Woman's Creek Watershed (1984-87)
Simulated and Observed Snow Depth in Young Woman's Creek Watershed (1988-91)
92
-------
10'
Simulated
Observed
- L
10'
en
LJ_
CJ
u>
10
10
-1
0.1 0.5 1 2 5 10 20 30 50 70 80 90 95 98 99 99
Percent of Time Flow Exceeded
FLOW FREQUENCY SIMULATION FOR YOUNG WOMANS CREEK NEAR RENOVO, PA
-------
on
Li_
CJ
4
2
0
4,000
3,600
3,200
2,800
2,400
2,000
1 ,600
1,200
800
400
0
iaiiljyjjljiu .Wl L. ....I.Jii. LlLiL Jl UiJL... Lj>,l,ii..LiitlJitl..Jiik..L.».... iL.iiJiiiiLullk.iul.
i i i r
\ \ i i i i i i i i i i i i i i r
n i i i i i i i i r
n i i r
SIM FLOW
OBS FLOW
JFMAMJJASONDJFMAMJJASONOJFMAMJJASOND
JFMAMJJASOND
1984 1985 1986 1987
SIMULATED AND OBSERVED FLOW FOR YOUNG WOMAN'S CREEK NEAR RENOVO, PA, 1984-87
-------
ex.
a.
to
Li-
es
*
o
4
2
0
1 ,000
900
800
700
600
500
400
300
200
100
JiUi.i ,J>. ,
,. tJi.Jti... i .Ui
.jll,,,IA.llllMLliy..J Ji..i.AJn,.iLu,lilii,dll.l .ill.,
JV\
i i '<' iN>
SIM FLOW
OBS FLOW
.!.»! .J.L.I -P
JFMAMJJASOND
1988
JFMAMJJASOND
1989
1990
JFMAMJJASOND JFMAMJJASOND
1991
SIMULATED AND OBSERVED FLOW FOR YOUNG WOMAN'S CREEK NEAR RENOVO, PA, 1988-91
-------
OtC
Q_
20
18
16
14
12
10
8
6
4
2
SIM SNOW DEPTH
OBS SNOW DEPTH
1 1 1 1 1 1 L/.
k
:L> i i i i i i i
l 1 1 1 1 1 1
1
JFMAMJJASOND
1984
JFMAMJJASONDJFMAMJJASOND
1985
1986
JFMAMJJASOND
1987
SIMULATED AND OBSERVED SNOW DEPTH IN YOUNG WOMAN'S CREEK WATERSHED, 1984-87
-------
VO
36
32
24
20
16
12
JiLu JL... A\ ill L ..ill. u. ..*.. A.. lkJj.u iJi.J J..M UiLjll..JAliiiJlAL,ily.J Ji..^!.^.^.!..!!.^!.!].!^!.!! .Jii.
40 I i i i i i i i i \ i i i i i i i i r~i i i i i i i i i i i i i i i i i i i i i i i i i i i i r
-X.
SIM SNOW DEPTH
DBS SNOW DEPTH
; »
11* r *
'V'.'1
i i i i i i ...i
JFMAMJJASOND
1988
J
JFMAMJJASOND
1989
JFMAMJJASOND
1990
i i i i i i i.
JFMAMJJASOND
1991
SIMULATED AND OBSERVED SNOW DEPTH IN YOUNG WOMAN'S CREEK WATERSHED, 1988-91
-------
RUN
GLOBAL
SHENANDOAH RIVER (SEGMENT 190) 9103-17 - FOREST N TESTING FINAL RUN
START 1984/01/01 END 1991/12/31
RUN INTERP OUTPUT LEVEL 4
RESUME 0 RUN 1
END GLOBAL
FILES
WDM
MESSU
***< FILE NAME
24 \usgs\9103-17\sh_forn.wdm
25 \usgs\9103-17\shentest.ech
90 \usgs\9103-17\shentest.out
END FILES
OPN SEQUENCE
INGRP INDELT 01:00
PERLND 191
GENER 1
GENER 2
GENER 3
COPY 1
GENER 191
END INGRP
END OPN SEQUENCE
SPEC-ACTIONS
*** kwd varnam optyp opn vari s1 s2 s3 tp multiply Ic Is ac as agfn ***
<****> < > < > <-> < ><-><-><-><->< > <><-> <><-> <--> ***
UVQUAN ornmin PERLND 191 ORNMN 5 3
<-l> *** dstp
GENER 191 3
END SPEC-ACTIONS
<1><2><3><-value--> tc tst nu
K 1 = ornmin
PERLND
ACTIVITY
# # ATMP SNOW PWAT SED PST
191 10111
END ACTIVITY
PRINT-INFO
# # ATMP SNOW PWAT SED PST
191 5 445
END PRINT-INFO
PWG PQAL MSTL PEST NITR PHOS TRAC ***
1010100
PWG PQAL MSTL PEST NITR PHOS TRAC PIVL***PY
554 12
GEN-INFO
# # NAME
191 FOREST
END GEN-INFO
NBLKS UCI
1 1
IN
1
OUT ENGL METR
1 90 0
ATEMP-DAT
ELEVATION DIFFERENCE BETWEEN GAGE AND PLS ***
# # ELDAT AIRTMP ***
191 -592.0 32.1
END ATEMP-DAT
PWAT-PARM1
# # CSNO RTOP UZFG VCS VUZ NVV VIFW VIRC
191 01110000
END PWAT-PARM1
PWAT-PARM2
# # ***FOREST LZSN INFILT LSUR
191 0.000 8.000 0.06 200.
END PWAT-PARM2
VLE ***
0
. SLSUR
0.22000
KVARY
0.000
AGWR
0.985
99
-------
PWAT-PARM4
# # CEPSC
191 0.00
END PWAT-PARM4
UZSN
1.000
NSUR
0.350
INTFU
3.000
IRC
0.750
LZETP
0.420
MON-INTERCEP
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
191 0.0600.0600.0600.1000.1600.1600.1600.1600.1600.1000.0600.060
END MON-INTERCEP
PWAT-STATE1
# # *** CEPS SURS UZS IFWS LZS AGWS GWVS
191 0.000 0.000 1.500 0.000 7.900 1.006 0.000
END PUAT-STATE1
SED-PARM1
# # CRV VSIV SDOP ***
191 101
END SED-PARM1
SED-PARM2
# # SMPF KRER JRER AFFIX COVER NVSI ***
191 1.000 0.271 2.000 0.002 0.000 2.000
END SED-PARM2
SED-PARM3
# # KSER JSER KGER JGER ***
191 13.00 2.000 0.000 2.000
END SED-PARM3
MON-COVER
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
191 .970 .970 .970 .970 .970 .970 .970 .970 .970 .970 .970 .970
END MON-COVER
SED-STOR
# # DETS ***
191 0.10
END SED-STOR
PSTEMP-PARM1
# # SLTV ULTV LGTV TSOP ***
191 1111
END PSTEMP-PARM1
PSTEMP-PARM2
# # ASLT
191 32.0
END PSTEMP-PARM2
BSLT
0.95
ULTP1
32.0
ULTP2
0.90
LGTP1
32.0
LGTP2
0.0
MON-ASLT
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
191 33. 33. 35. 41. 47. 50. 50. 50. 50. 47. 40. 35.
END MON-ASLT
MON-BSLT
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
191 0.30 0.30 0.35 0.45 0.52 0.57 0.57 0.57 0.56 0.52 0.45 0.42
END MON-BSLT
MON-ULTP1
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
191 36. 36. 37. 40. 45. 48. 48. 48. 48. 45. 40. 38.
END MON-ULTP1
MON-ULTP2
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
191 .22 .22 .25 .40 .50 .55 .55 .55 .55 .50 .45 .25
END MON-ULTP2
100
-------
MON-LGTP1
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
191 49.0 48.5 50.0 55.0 58.0 60.0 61.0 61.5 59.5 56.0 52.0 49.5
END MON-LGTP1
PSTEMP-TEMPS
# # AIRTC SLTMP ULTMP LGTMP ***
191 32.0 32.0 32.0 50.0
END PSTEMP-TEMPS
PWT-PARM1
.# # IDV ICV GDV GCV ***
191 1010
END PUT-PARM1
PWT-PARM2
# # ELEV IDOXP IC02P ADOXP AC02P ***
191 1880. 8.80 0.00 8.80 0.00
END PWT-PARM2
MON-IFWDOX
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
191 12.7 12.7 11.2 9.70 7.40 6.50 5.50 5.50 6.00 8.40 9.40 11.6
END MON-IFWDOX
MON-GRNDDOX
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
191 12.0 12.0 11.0 10.0 7.50 5.50 4.50 4.00 4.50 7.50 9.0 10.0
END MON-GRNDDOX
PWT-GASES
# # SODOX SOC02 IODOX IOC02 AODOX AOC02 ***
191 , 14.5 0.0 12.7 0.0 10.0 0.0
END PWT-GASES
*** SECTION MSTLAY ***
MST-PARM
FACTORS USED TO ADJUST SOLUTE LEACHING RATES ***
SLMPF ULPF LLPF ***
# # ***
191 0.9 3.0 1.5
END MST-PARM
MST-TOPSTOR INITIAL MOISTURE TOP SOIL LAYER STORAGES DEFAULTED TO ZERO ***
MST-TOPFLX INITIAL MOISTURE FLUXES TOP SOIL LAYER DEFAULTED TO ZERO ***
*** SECTION NITR ***
SOIL-DATA
SOIL LAYER DEPTHS AND BULK DENSITIES ***
# - # DEPTHS (IN) BULK DENSITY (LB/FT3) ***
SURFACE UPPER LOWER GROUNDW SURFACE UPPER LOWER GROUNDW ***
191 0.39 11.42 35.43 60. 84.3 84.3 84.3 90.5
END SOIL-DATA
NIT-FLAGS
NITROGEN FLAGS ***
# - # VNUT FORA ITMX BNUM CNUM NUPT FIXN AMVO ALPN VNPR ***
191 1 1 100 3 1 2 11
END NIT-FLAGS
NIT-AD-FLAGS
Atmospheric Deposition Flags ***
N03 NH3 ORGN ***
sur upp sur upp sur upp ***
# - # F C F C FCFC FCFC***
191 -1000-1000-1000
101
-------
END NIT-AD-FLAGS
NIT-UPIMCSAT
CSUNI
# - # (UG/L)
191 20.
END NIT-UPIMCSAT
SURFACE LAYER
CSUAM CSINI
(UG/L) (UG/L)
5. 10.
CSIAM ***
(UG/L) ***
2.0
NIT-UPIMCSAT
CSUNI
# - # (UG/L)
191 20.
END NIT-UPIMCSAT
UPPER LAYER
CSUAM CSINI
(UG/L) (UG/L)
5. 10.
CSIAM ***
(UG/L) ***
2.0
NIT-UPIMCSAT
CSUNI
# - # (UG/L)
191 20.
END NIT-UPIMCSAT
NIT-UPIMCSAT
CSUNI
# - # (UG/L)
191 20.0
END NIT-UPIMCSAT
LOWER LAYER
CSUAM CSINI
(UG/L) (UG/L)
10. 10.
GROUNDUATER LAYER
CSUAM CSINI
(UG/L) (UG/L)
10. 10.
CSIAM ***
(UG/L) ***
2.0
CSIAM ***
(UG/L) ***
3.0
MON-NITUPNI SURFACE LAYER
Maximum Plant Uptake Rate for Nitrate (mg/l/day) ***
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV
191 0. 0. 5. 20. 25. 30. 30. 30. 30. 30. 25.
END MON-NITUPNI
MON-NITUPNI UPPER LAYER
Maximum Plant Uptake Rate for Nitrate (mg/l/day)
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT
191 1.0 1.0 3. 10. 15. 15. 15. 15. 15. 10.
END MON-NITUPNI
NOV
5.
DEC
0.
DEC
1.0
MON-NITUPNI LOWER LAYER
Maximum Plant Uptake Rate for Nitrate (mg/l/day) ***
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC
191 .10 .10 0.30 0.70 0.90 1.0 1.0 1.0 1.0 0.80 0.50 0.10
END MON-NITUPNI
MON-NITUPNI GROUND WATER LAYER
Maximum Plant Uptake Rate for Nitrate (mg/l/day)
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT
191 0. 0. 0. 0. 0. 0. 0. 0. 0. 0.
END MON-NITUPNI
NOV
0.
MON-NITUPAM SURFACE LAYER
Maximum Plant Uptake Rate for Ammonia (mg/l/day) ***
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV
191 0. 0. 2.0 10. 12.5 15. 15. 15. 15. 15. 5.0
END MON-NITUPAM
DEC
0.
DEC
0.
MON-NITUPAM UPPER LAYER
Maximum Plant Uptake Rate for Ammonia (mg/l/day) ***
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV
191 2. 2. 5.0 12. 20. 20. 20. 20. 20. 15. 12.
END MON-NITUPAM
DEC
2.
MON-NITUPAM LOWER LAYER
Maximum Plant Uptake Rate for Ammonia (mg/l/day) ***
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV
191 .10 .10 .30 .70 .80 .80 .80 .80 .80 .70 .60
END MON-NITUPAM
DEC
.10
MON-NITUPAM
GROUND WATER LAYER
102
-------
Maximum Plant Uptake Rate for Ammonia (mg/t/day) ***
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
191 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0.
END MON-NITUPAM
MON-NITIMNI SURFACE LAYER
Maximum Immobilization Rate for Nitrate (mg/l/day) ***
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
191 .05 .05 .05 .10 .10 .10 .15 .15 .10 .10 .10 .05
END MON-NITIMNI
MON-NITIMNI UPPER LAYER
Maximum Immobilization Rate for Nitrate (mg/l/day) ***
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
191 .05 .05 .05 .05 .05 .10 .10 .10 .10 .05 .05 .05
END MON-NITIMNI
MON-NITIMNI LOWER LAYER
Maximum Immobilization Rate for Nitrate (mg/l/day) ***
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
191 .02 .02 .02 .04 .04 .05 .05 .05 .04 .04 .04 .02
END MON-NITIMNI
MON-NITIMNI GROUNDWATER LAYER
Maximum Immobilization Rate for Nitrate (mg/l/day) ***
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
191 .05 .05 .05 .10 .10 .10 .15 ..15 .10 .10 .10 .05
END MON-NITIMNI
MON-NITIMAM SURFACE LAYER
Maximum Immobilization Rate for Ammonia (mg/l/day) ***
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
191 .10 .10 .10 .10 .10 .20 .20 .20 .20 .10 .10 .10
END MON-NITIMAM
MON-NITIMAM UPPER LAYER
Maximum Immobilization Rate for Ammonia (mg/l/day) ***
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
191 .10 .10 .10 .10 .10 .10 .10 .10 .10 .10 .10 .10
END MON-NITIMAM
MON-NITIMAM LOWER LAYER
Maximum Immobilization Rate for Ammonia (mg/l/day) ***
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
191 .01 .01 .01 .01 .02 .02 .02 .02 .02 .01 .01 .01
END MON-NITIMAM
MON-NITIMAM GROUNDWATER LAYER
Maximum Immobilization Rate for Ammonia (mg/l/day) ***
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
191 .05 .05 .05 .05 .05 .10 .10 .10 .10 .05 .05 .05
END MON-NITIMAM
MON-NITAGUTF SURFACE LAYER
Monthly Above-Ground Fractions for Plant Uptake ***
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
191 .3 .3 .3 .7 .7 .7 .7 .4 .4 .4 .4 .3
END MON-NITAGUTF
MON-NITAGUTF UPPER LAYER
Monthly Above-Ground Fractions for Plant Uptake ***
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
191 .3 .3 .3 .5 .7 .7 .7 .4 .4 .4 .4 .3
END MON-NITAGUTF
MON-NITAGUTF LOWER LAYER
Monthly Above-Ground Fractions for Plant Uptake ***
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
191 .3 .3 .3 .5 .7 .7 .7 .4 .4 .4 .4 .3
103
-------
END MON-NITAGUTF
HON-NITAGUTF GROUNDWATER LAYER
Monthly Above-Ground Fractions for Plant Uptake ***
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
191 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0.
END MON-NITAGUTF
NIT-ORGPM
ORGANIC N TRANSFORMATION PARAMETERS FOR SURFACE LAYER ***
x - x KLON KRON KONLR THNLR ***
191 4500. 33000.00 .0001 1.07
END NIT-ORGPM
NIT-ORGPM
ORGANIC N TRANSFORMATION PARAMETERS FOR UPPER LAYER ***
X - x KLON KRON KONLR THNLR ***
191 4500. 33000.00 .00001 1.07
END NIT-ORGPM
NIT-ORGPM
ORGANIC N TRANSFORMATION PARAMETERS FOR LOWER LAYER ***
x - x KLON KRON KONLR THNLR ***
191 4500. 33000.00 .00001 1.07
END NIT-ORGPM
NIT-ORGPM
ORGANIC N TRANSFORMATION PARAMETERS FOR ACTIVE GU LAYER ***
X - X KLON KRON KONLR THNLR ***
191 4500. 33000.00 .00001 1.07
END NIT-ORGPM
MON-NPRETBG SURFACE LAYER
Return rates for below-ground plant N in surface layer (/day) ***
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
191 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0.
END MON-NPRETBG
MON-NPRETBG UPPER LAYER
Return rates for below-ground plant N in upper layer ***
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
191 6.E-46.E-46.E-46.E-46.E-46.E-46.E-46.E-46.E-46.E-46.E-46.E-4
END MON-NPRETBG
MON-NPRETBG LOWER LAYER
Return rates for below-ground plant N in lower layer ***
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
191 4.E-44.E-44.E-44.E-44.E-44.E-44.E-44.E-44.E-44.E-44.E-44.E-4
END MON-NPRETBG
MON-NPRETBG GROUNDWATER LAYER
Return rates for below-ground plant N in GW layer ***
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
191 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0.
END MON-NPRETBG
MON-NPRETFBG
Monthly refractory fractions for below-ground plant N return ***
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
191 .05 .05 .05 .05 .05 .05 .05 .05 .05 .05 .05 .05
END MON-NPRETFBG
MON-NPRETAG
Monthly return rates for above-ground plant N to Litter (/day) **
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
191 0. 0. 0. 0. 0. 0. 0. 0. 0..0009.0002 0.
END MON-NPRETAG
104
-------
MON-NPRETLI SURFACE LAYER
Monthly return rates for litter N to SZ (/day) ***
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
191 .0007.0007.0007.0007.0007.0007.0007.0007.0007.0007.0007.0007
END MON-NPRETLI
MON-NPRETLI UPPER LAYER
Monthly return rates for litter N to UZ (/day) ***
# # JAN FEB MAR APR MAY JUN. JUL AUG SEP OCT NOV DEC ***
191 .0015.0015.0015.0015.0015.0015.0015.0015.0015.0015.0015.0015
END MON-NPRETLI
MON-NPRETFLI
Monthly refractory fractions for litter N return to SZ/UZ ***
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
191 .05 .05 .05 .05 .05 .05 .05 .05 .05 .05 '.05 .05
END MON-NPRETFLI
NIT-FSTGEN
UPT-FRAC.< TEMP-PARMS(THETA) > ***
# # N03 NH4 PLN KDSA KADA KIMN KAM KDNI KNI KIMA ***
191 0.3 0.7 1.07 1.05 1.05 1.07 1.07 1.07 1.05 1.07
END NIT-FSTGEN
NIT-FSTPM
*** NITROGEN FIRST-ORDER RATES FOR SURFACE LAYER (/DAY)
# #*** KDSAM KADAM KIMNI KAM KDNI KNI KIMAM
191 .0 .005 0. 10. 0.0
END NIT-FSTPM
NIT-FSTPM
*** NITROGEN FIRST-ORDER RATES FOR UPPER LAYER (/DAY)
# #*** KDSAM KADAM KIMNI KAM KDN! KNI KIMAM
191 .0 .0030 0. 10. 0.0
END NIT-FSTPM
NIT-FSTPM
*** NITROGEN FIRST-ORDER RATES FOR LOWER LAYER (/DAY)
# #*** KDSAM KADAM KIMNI KAM KDNI KNI KIMAM
191 .0 .0025 0. 3. 0.0
END NIT-FSTPM
NIT-FSTPM
*** NITROGEN FIRST-ORDER RATES FOR GROUNDWATER LAYER (/DAY)
# #*** KDSAM KADAM KIMNI KAM KDNI KNI
191 .0 .00030 0. 3.
END NIT-FSTPM
KIMAM
.0
NIT-CMAX
# #
191
END NIT-CMAX
NIT-SVALPM
MAXIMUM SOLUBILITY OF AMMONIUM
CMAX
(PPM)
5000.
SURFACE
***
***
***
NITROGEN SINGLE VALUE FREUNDLICH ADSORPTION/DESORPTION PARAMTERS ***
XFIX K1 N1***
# # (PPM)
191 2.
END NIT-SVALPM
1.0
1.50
NIT-SVALPM UPPER
NITROGEN SINGLE VALUE FREUNDLICH ADSORPTION/DESORPTION PARAMETERS ***
XFIX K1 N1***
# # (PPM) ***
191 2. 1.0 1.20
END NIT-SVALPM
105
-------
NIT-SVALPM LOUER
NITROGEN SINGLE VALUE FREUNDLICH ADSORPTOIN/DESORPTION PARAMETERS ***
XFIX K1 N1***
# # (PPM) ***
191 .55 0.5 1.20
END NIT-SVALPM
NIT-SVALPM GROUNDWATER
NITROGEN SINGLE VALUE FREUNDLICH ADSORPTION/DESORPTION PARAMETERS ***
XFIX K1 N1***
# # (PPM) ***
191 .25 0.5 1.10
END NIT-SVALPM
NIT-STOR1 SURFACE-BLK 1
INITIAL STORAGE OF N FORMS IN UPPER LAYER LB/AC ***
# # LORGN AMAD AMSU N03 PLTN
191 550. 7.0 0.5 1. 200.
END NIT-STOR1
NIT-STOR1 LOWER LAYER
INITIAL STORAGE OF N FORMS IN LOUER LAYER LB/AC ***
# # LORGN AMAD AMSU N03 PLTN
191 300. 6.0 0.5 1. 50.
RORGN***
200.
RORGN***
2200.
RORGN***
1200.
END NIT-STOR1
NIT-STOR1 GROUNDWATER LAYER
INIT!AL STORAGE OF N FORMS IN GROUNDWATER LAYER LB/AC ***
# # LORGN AMAD AMSU N03 PLTN RORGN***
191 200. 5.0 0.10 .5 .0 1000.
END NIT-STOR1
NIT-STOR2
INITIAL N IN INTERFLOW, ABOVE GROUND, AND LITTER STORAGE (LB/AC) ***
# # IAMSU IN03 ISLON ISRON AGPLTN LITTRN***
191 500. 30.
END NIT-STOR2
END PERLND
EXT SOURCES
<-Volume-> SsysSgap<--Mult-->Tran <-Target vols> <-Grp> <-Member-> ***
# # tern strg<-factor->strg # # it # ***
WDM 105 HPRC 10 ENGLZERO SAME PERLND 191 EXTNL PREC
WDM 40 EVAP ENGLZERO 0.86 DIV PERLND 191 EXTNL PETINP
WDM 49 ATMP ENGL SAME PERLND 191 EXTNL GATMP
WDM
WDM
WDM
WDM
ATM DEPOSITION
541 NH4X
542 N03X
543 N03X
545 ORGN
ENGL
ENGL
ENGL
ENGL
DIV PERLND 191
DIV PERLND 191
DIV PERLND 191
DIV PERLND 191
EXTNL NIADFX 2 1
EXTNL NIADFX 1 1
EXTNL NIADFX 1 1
EXTNL NIADFX 3 1
END EXT SOURCES
NETWORK
<-Volume-> <-Grp> <-Member-><--Mutt-->Tran <-Target vols> <-Grp> <-Member-> ***
^, M #<-factor->strg # # # # ***
PERLND 191 NITR
PON03
GENER
1
INPUT ONE
106
-------
PERLND 191 PWATER PERO
GENER 1 OUTPUT TIMSER
PERLND 191 NITR PONH4
PERLND 191 PWATER PERO
GENER 2 OUTPUT TIMSER
PERLND 191 NITR POORN
PERLND 191 PUATER PERO
GENER 3 OUTPUT TIMSER
PERLND 191 NITR SN 5
PERLND 191 NITR UN 5
PERLND 191 NITR LN 5
PERLND 191 NITR AN 5
END NETWORK
0.0833 GENER 1
0.368 SAME COPY 1
0.0833
0.368
0.0833
0.368
GENER
GENER
SAME COPY
GENER
GENER
SAME COPY
INPUT TWO
INPUT MEAN 1
INPUT ONE
INPUT TWO
INPUT MEAN 2
INPUT ONE
INPUT TWO
INPUT MEAN 3
COPY 1 INPUT POINT 1
COPY 1 INPUT POINT 1
COPY 1 INPUT POINT 1
COPY 1 INPUT POINT 1
EXT TARGETS
<-Volume-> <-Grp> <-Member-x--Mult-->Tran <-Volume-> Tsys Tgap Amd ***
if # #<-factor->strg # # tem strg strg***
COPY
COPY
COPY
PERLND
PERLND
PERLND
PERLND
PERLND
COPY
PERLND
PERLND
PERLND
PERLND
PERLND
GENER
1 OUTPUT
1 OUTPUT
1 OUTPUT
191 PSTEMP
191 PSTEMP
191 PSTEMP
191 PWATER
191 NITR
1 OUTPUT
191 NITR
191 NITR
191 NITR
191 NITR
191 NITR
191 OUTPUT
MEAN 1
MEAN 2
MEAN 3
SLTMP
ULTMP
LGTMP
PERO
AGPLTN 1
POINT 1
LITTRN 1
TOTNIT 1
TN 5
TN 1
TN 7
TIMSER
END EXT TARGETS
GENER
OPCODE
#thru# code ***
1 3 19
191 24
END OPCODE
PARM ***
#thru# constant
191 0
END PARM ***
END GENER
COPY
TIMESERIES
#thru# NPT NMN
1 1 3
END TIMESERIES
END COPY
END RUN
AVER WDM
AVER WDM
AVER WDM
AVER WDM
AVER WDM
AVER WDM
AVER WDM
AVER WDM
AVER WDM
AVER WDM
AVER WDM
AVER WDM
AVER WDM
AVER WDM
SUM WDM
2001 N03X
2002 NH3X
2003 ORGN
2004 TEMP
2005 TEMP
2006 TEMP
2007 HYDR
2008 NITR
2012 NITR
2009 NITR
2010 NITR
2011 NITR
2013 NITR
2014 NITR
2016 NITR
ENGL AGGR REPL
ENGL AGGR REPL
ENGL AGGR REPL
ENGL AGGR REPL
ENGL AGGR REPL
ENGL AGGR REPL
ENGL AGGR REPL
ENGL AGGR REPL
ENGL AGGR REPL
ENGL AGGR REPL
ENGL AGGR REPL
ENGL AGGR REPL
ENGL AGGR REPL
ENGL AGGR REPL
ENGL AGGR REPL
107
-------
Appendix D. Hunting Creek UCI
108
-------
RUN
GLOBAL
Hunting Creek Trtb Near Foxville, MD
START 1984/01/01 END
RUN INTERP OUTPUT LEVEL 4
RESUME 0 RUN 1
END GLOBAL
(SEGMENT 750) - 9103-25 FOREST N TESTING FINAL RUN
1991/12/31
FILES
WDM
HESSU
END
***< FILE NAME-
24 CATOCTIN.WDM
25 CATOCTIN.ECH
90 CATOCTIN.OUT
FILES
OPN SEQUENCE
INGRP
PERLND
RCHRES
COPY
GENER
GENER
GENER
GENER
GENER
COPY
END INGRP
END OPN SEQUENCE
INDELT 01:00
751
750 ***
600 ***
1
2
3
4
751
1
SPEC-ACTIONS
*** kwd varnam optyp opn vari s1 s2 s3 tp multiply Ic Is ac as agfn ***
<****> < > < > <-> < ><-><-><-><->< > <><-> <><-> <--> ***
UVQUAN ornmin PERLND 751 ORNMN 5 3
*** dstp
GENER 751 3
END SPEC-ACTIONS
<1><2><3><-value--> tc tst nu
K 1 = ornmin
PERLND
ACTIVITY
# # ATMP SNOW PWAT SED PST
751 11111
END ACTIVITY
PRINT-INFO
# # ATMP SNOW PWAT SED PST
751 55545
END PRINT-INFO
PWG PQAL MSTL PEST NITR PHOS TRAC
1010100
PWG PQAL MSTL PEST NITR PHOS TRAC PIVL***PY
5554 12
GEN-INFO
# # NAME
751 FOREST
END GEN-INFO
NBLKS UCI
1 1
IN
1
OUT ENGL METR
1 90 0
ATEMP-DAT
# # ELDAT
751 -250.0
END ATEMP-DAT
AIRTMP ***
20.0
ICE-FLAG
# # I CFG ***
751 1
END ICE-FLAG
SNOW-PARM1
# #
751
LAT
(DEC)
39.4
ELEV SHADE
(FT)
1500. 0.90
SNOWCF COVIND ***
(IN) ***
1.22 0.25
109
-------
END SNOW-PARM1
SNOW-PARM2
# # RDCSN
751 0.120
END SNOW-PARM2
TSNOW
32.0
SNOEVP
0.150
SNOW-INIT1
# # PACK-SNOW PACK-ICE PACK-WATR
751 2.500 0.250 0.200
END SNOU-INIT1
CCFACT
1.000
RDENPF
0.20
MWATER MGHELT ***
0.030 0.015
DULL PAKTMP ***
400. 30.0
SNOU-INIT2
# # COVINX
751 0.01
END SNOW-INIT2
XLNMLT
0.00
SKYCLR
0.90
PUAT-PARM1
# # CSNO RTOP UZFG VCS VUZ NVV
751 111110
END PWAT-PARM1
PWAT-PARM2
# # ***FOREST LZSN
751 0.200 3.000
END PWAT-PARM2
PWAT-PARM3
*** PETMAX PETMIN
*** x - x (deg F) (deg F)
751 35.0 30.0
END PWAT-PARM3
PWAT-PARM4
# # CEPSC UZSN
751 0.00 0.400
END PWAT-PARM4
INFILT
0.085
VIFU VIRC
0 0
LSUR
220.
INFEXP
2.0
NSUR
0.350
MON-INTERCEP
# it JAN FEB MAR APR MAY JUN
751 0.0500.0500.0500.1000.1600 .20
END MON-INTERCEP
INFILD
2.0
INTFW
4.000
JUL AUG
.20 .20
VLE ***
1
SLSUR KVARY AGWR
0.16000 1.000 0.955
DEEPFR BASETP AGWETP
0.0 0.0 0.0
IRC LZETP ***
0.820 0.300
SEP OCT NOV DEC ***
.20 .15 .050 .050
MON-LZETPARM
# # JAN FEB MAR APR MAY JUN JUL AUG
751 0.20 0.20 0.20 0.30 0.32 0.32 0.32 0.32
END MON-LZETPARM
MON-UZSN
# # JAN FEB MAR APR MAY JUN JUL AUG
751 0.35 0.40 0.45 0.60 0.80 0.80 0.80 0.80
END MON-UZSN
SEP OCT NOV DEC ***
0.32 0.30 0.20 0.20
SEP OCT NOV DEC ***
0.80 0.60 0.50 0.45
PWAT-STATE1
# # *** CEPS
751 0.000
END PUAT-STATE1
SURS
0.000
SED-PARM1
# # CRV VSIV SDOP ***
751 101
END SED-PARM1
SED-PARM2
# # SMPF
751 1.000
END SED-PARM2
SED-PARM3
KRER
0.268
UZS
0.800
JRER
2.000
IFWS
0.000
AFFIX
0.002
LZS AGWS GWVS
4.00 1.000 1.000
COVER NVSI ***
0.000 2.000
110
-------
# # KSER JSER KGER JGER ***
751 0.071 2.000 0.000 2.000
END SED-PARM3
MON-COVER
# # JAN FEB MAR APR MAY JUM JUL AUG SEP OCT NOV DEC ***
751 .970 .970 .970 .970 .970 .970 .970 .970 .970 .970 .970 .970
END MON-COVER
SED-STOR
# #
751
END SED-STOR
DETS ***
0.03
PSTEMP-PARM1
# # SLTV ULTV LGTV TSOP
751 1111
END PSTEMP-PARM1
PSTEMP-PARM2
# # ASLT
751 32.0
END PSTEMP-PARM2
BSLT
0.95
MON-ASLT
# # JAN
751 33.
END MON-ASLT
FEB
33.
MAR
35.
APR
41.
MON-BSLT
# # JAN FEB MAR APR
751 0.30 0.30 0.35 0.45
END MON-BSLT
MON-ULTP1
# # JAN
751 36.
END MON-ULTP1
FEB
36.
MAR APR
37. 40.
ULTP1 ULTP2 LGTP1 LGTP2 ***
32.0 0.90 32.0 0.0
MAY JUN JUL AUG SEP OCT NOV DEC ***
45. 47. 47. 47. 47. 45. 40. 35.
MAY JUN JUL AUG SEP OCT NOV DEC ***
0.52 0.55 0.55 0.55 0.55 0.52 0.45 0.42
MAY JUN JUL AUG SEP OCT NOV DEC ***
43. 45. 45. 45. 45. 43. 40. 38.
MON-ULTP2
# # JAN FEB MAR APR
751 .22 .22 .25 .40
END MON-ULTP2
MON-LGTP1
# # JAN FEB MAR APR
751 49.0 48.5 50.0 51.0
END MON-LGTP1
MAY JUN JUL AUG SEP OCT NOV DEC ***
.50 .52 .52 .52 .52 .50 .45 .25
MAY JUN JUL AUG SEP OCT NOV DEC ***
52.0 53.5 54.5 55.0 54.5 53.5 52.0 49.5
PSTEMP-TEMPS
# # AIRTC
751 32.0
END PSTEMP-TEMPS
SLTMP
32.0
ULTMP LGTMP ***
32.0 50.0
PWT-PARM1
# # IDV
751 1
END PWT-PARM1
ICV GDV
0 1
GCV
0
PWT-PARM2
# # ELEV
751 770.
END PUT-PARM2
IDOXP
8.80
IC02P ADOXP AC02P ***
0.00 8.80 0.00
MON-IFUDOX
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC
751 12.7 12.7 11.2 9.70 7.40 6.50 5.50 5.50 6.00 8.40 9.40 11.6
END MON-IFUDOX
111
-------
MON-GRNODOX
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC
751 12.0 12.0 11.0 10.0 7.50 5.50 4.50 4.00 4.50 7.50 9.0 10.0
END MON-GRNDDOX
PUT-GASES
# # SODOX
751 14.5
END PUT-GASES
SOC02
0.0
IODOX
12.7
IOC02
0.0
AODOX
10.0
AOC02 ***
0.0
*** SECTION MSTLAY ***
MST-PARM
FACTORS USED TO ADJUST SOLUTE LEACHING RATES ***
SLMPF ULPF LLPF ***
ft # ***
751 756 0.9 3.0 1.5
END MST-PARM
MST-TOPSTOR INITIAL MOISTURE TOP SOIL LAYER STORAGES DEFAULTED TO ZERO ***
MST-TOPFLX INITIAL MOISTURE FLUXES TOP SOIL LAYER DEFAULTED TO ZERO ***
*** SECTION NITR ***
SOIL-DATA
SOIL LAYER DEPTHS AND BULK DENSITIES ***
# - # DEPTHS (IN) BULK DENSITY (LB/FT3) ***
SURFACE UPPER LOWER GROUNDW SURFACE UPPER LOWER GROUNDW ***
751 0.39 11.42 35.43 60. 84.3 84.3 84.3 91.1
END SOIL-DATA
NIT-FLAGS
NITROGEN FLAGS ***
# - # VNUT FORA ITMX BNUM CNUM NUPT FIXN AMVO ALPN VNPR ***
751 1 1 100 3 1 2 11
END NIT-FLAGS
NIT-AD-FLAGS
Atmospheric Deposition Flags ***
NH3 ORGN ***
sur upp sur upp ***
F C F C F C F C ***
-10 00 -10 00
N03
sur upp
# - # F C F C
751 -1000
END NIT-AD-FLAGS
NIT-UPIMCSAT
CSUNI
# - # (UG/L)
751 20.
END NIT-UPIMCSAT
SURFACE LAYER
CSUAM CSINI
(UG/L) (UG/L)
5. 10.
CSIAM ***
(UG/L) ***
2.
NIT-UPIMCSAT
CSUNI
# - # (UG/L)
751 20.
END NIT-UPIMCSAT
NIT-UPIMCSAT
CSUNI
# - # (UG/L)
751 20.
END NIT-UPIMCSAT
NIT-UPIMCSAT
CSUNI
# - # (UG/L)
751 20.
END NIT-UPIMCSAT
UPPER LAYER
CSUAM CSINI
(UG/L) (UG/L)
5. 10.
LOWER LAYER
CSUAM CSINI
(UG/L) (UG/L)
10. 10.
CSIAM ***
(UG/L) ***
2.
CSIAM ***
(UG/L) ***
2.
GROUNDWATER LAYER
CSUAM CSINI CSIAM ***
(UG/L) (UG/L) (UG/L) ***
10. 10. 3.
112
-------
MON-NITUPNI SURFACE LAYER
Maximum Plant Uptake Rate for Nitrate (mg/l/day) ***
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
751 0. 0. 5. 25. 25. 25. 10. 10. 10. 10. 5. 0.
END MON-NITUPNI
MON-NITUPNI UPPER LAYER
Maximum Plant Uptake Rate for Nitrate (mg/l/day) ***
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
751 .5 .5 .5 3. 70. 100. 100. 100. 100. 70. 10. 1.0
END MON-NITUPNI
MON-NITUPNI LOWER LAYER
Maximum Plant Uptake Rate for Nitrate (mg/l/day) ***
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
751 .1 .1 .1 1.5 3.0 5.0 5.0 5.0 S'.O 5.0 1.0 .2
END MON-NITUPNI
MON-NITUPNI GROUND WATER LAYER
Maximum Plant Uptake Rate for Nitrate (mg/l/day) ***
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
751 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0.
END MON-NITUPNI
MON-NITUPAM SURFACE LAYER
Maximum Plant Uptake Rate for Ammonia (mg/l/day) ***
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
751 0. 0. 2. 15. 15. 15. 12. 12. 12. 8. 2. 0.
END MON-NITUPAM
MON-NITUPAM UPPER LAYER
Maximum Plant Uptake Rate for Ammonia (mg/l/day) ***
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
751 .5 .5 .5 5. 70. 100. 100. 100. 100. 70. 10. 1.0
END MON-NITUPAM
MON-NITUPAM LOWER LAYER
Maximum Plant Uptake Rate for Ammonia (/day) ***
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
751 .1 .1 .1 2. 3.0 5.0 5.0 5.0 5.0 5.0 1.0 .2
END MON-NITUPAM
MON-NITUPAM GROUND WATER LAYER
Maximum Plant Uptake Rate for Ammonia (/day) ***
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
751 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0.
END MON-NITUPAM
MON-NITIMNI SURFACE LAYER
Maximum Immobilization Rate for Nitrate (mg/l/day) ***
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
751 .0 .0 .10 .20 .20 .20 .30 .30 .20 .20 .20 .0
END MON-NITIMNI
MON-NITIMNI UPPER LAYER
Maximum Immobilization Rate for Nitrate (mg/l/day) ***
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
751 2. 2. 2. .60 .60 .60 .60 2.0 2.0 2.0 2.0 2.0
END MON-NITIMNI
MON-NITIMNI LOWER LAYER
Maximum Immobilization Rate for Nitrate (mg/l/day) ***
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
751 .5 .5 .5 .15 .15 .15 .15 .15 .15 .5 .5 .5
END MON-NITIMNI
MON-NITIMNI GROUNDWATER LAYER
Maximum Immobilization Rate for Nitrate (/day) ***
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
113
-------
751 .0 .0 .0 .1 .1 .1 .1 .1 .1 .1 .1 .0
END MON-NITIMNI
MON-NITIMAM SURFACE LAYER
Maximum Immobilization Rate for Ammonia (mg/l/day) ***
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
751 .5 .5 .45 .45 .45 .90 .90 .90 .90 .5 .5 .5
END MON-NITIMAM
MON-NITIMAM UPPER LAYER
Maximum Immobilization Rate for Ammonia (mg/l/day) ***
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
751 1.5 1.5 1.5 1.2 1.2 1.2 1.2 1.2 1.2 1.3 1.5 1.5
END MON-NITIMAM
MON-NITIMAM LOWER LAYER
Maximum Immobilization Rate for Ammonia (mg/l/day) ***
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
751 .5 .5 .3 .2 .20 .20 .20 .20 .20 .20 .30 .5
END MON-NITIMAM
MON-NITIMAM GROUNDWATER LAYER
Maximum Immobilization Rate for Ammonia (mg/l/day) ***
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
751 .3 .3 .3 .3 .10 .10 .10 .10 .10 .10 .3 .3
END MON-NITIMAM
MON-NITAGUTF SURFACE LAYER
Monthly Above-Ground Fractions for Plant Uptake ***
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
751 .3 .3 .3 .7 .7 .7 .7 .4 .4 .4 .4 .3
END MON-NITAGUTF
MON-NITAGUTF UPPER LAYER
Monthly Above-Ground Fractions for Plant Uptake ***
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
751 .3 .3 .3 .5 .7 .7 .7 .4 .4 .4 .4 .3
END MON-NITAGUTF
MON-NITAGUTF LOWER LAYER
Monthly Above-Ground Fractions for Plant Uptake ***
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
751 .3 .3 .3 .5 .7 .7 .7 .4 .4 .4 .4 .3
END MON-NITAGUTF
MON-NITAGUTF GROUNDWATER LAYER
Monthly Above-Ground Fractions for Plant Uptake ***
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
751 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0.
END MON-NITAGUTF
NIT-ORGPM
ORGANIC N TRANSFORMATION PARAMETERS FOR SURFACE LAYER ***
x - x KLON KRON KONLR THNLR ***
751 7000. 40000. .0001 1.07
END NIT-ORGPM
NIT-ORGPM
ORGANIC N TRANSFORMATION PARAMETERS FOR UPPER LAYER ***
X - X KLON KRON KONLR THNLR ***
751 7000. 40000. .00001 1.07
END NIT-ORGPM
NIT-ORGPM
ORGANIC N TRANSFORMATION PARAMETERS FOR LOWER LAYER ***
X - X KLON KRON KONLR THNLR ***
751 7000. 40000. .00001 1.07
END NIT-ORGPM
114
-------
NIT-ORGPM
ORGANIC N TRANSFORMATION PARAMETERS FOR ACTIVE GW LAYER ***
X - x KLON KRON KONLR THNLR ***
751 7000. 40000. .00001 1.07
END NIT-ORGPM
MON-NPRETBG SURFACE' LAYER
Return rates for below-ground plant N in surface layer (/day) ***
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
751 .0 .0 .0 .0 .0 .0 .0 .0 .0 .0 .0 .0
END MON-NPRETBG
MON-NPRETBG UPPER LAYER
Return rates for below-ground plant N in upper layer ***
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
751 5.E-45.E-45.E-45.E-45.E-45.E-45.E-45.E-45.E-45.E-45.E-45.E-4
END MON-NPRETBG
MON-NPRETBG LOWER LAYER
Return rates for below-ground plant N in lower layer ***
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
751 3.E-43.E-43.E-43.E-43.E-43.E-43.E-43.E-43.E-43.E-43.E-43.E-4
END MON-NPRETBG
MON-NPRETBG GROUNDWATER LAYER
Return rates for below-ground plant N in GW layer ***
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
751 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0.
END MON-NPRETBG
MON-NPRETFBG
Monthly refractory fractions for below-ground plant N return ***
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
751 .05 .05 .05 .05 .05 .05 .05 .05 .05 .05 .05 .05
END MON-NPRETFBG
MON-NPRETAG
Monthly return rates for above-ground plant N to LitterC/day) ***
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
751 0. 0. 0. 0. 0. 0. 0. 0. 0..0012.0004 0.
END MON-NPRETAG
MON-NPRETLI SURFACE LAYER
Monthly return rates for litter N to SZ (/day) ***
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
751 .0007.0007.0007.0007.0007.0007.0007.0007.0007.0007.0007.0007
END MON-NPRETLI
MON-NPRETLI UPPER LAYER
Monthly return rates for litter N to UZ (/day) ***
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
751 .0015.0015.0015.0015.0015.0015.0015.0015.0015.0015.0015.0015
END MON-NPRETLI
MON-NPRETFLI
Monthly refractory fractions for litter N return to SZ/UZ ***
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
751 .05 .05 .05 .05 .05 .05 .05 .05 .05 .05 .05 .05
END MON-NPRETFLI
NIT-FSTGEN
UPT-FRAC.< TEMP-PARMS(THETA) >***
# # N03 NH4 PLN KDSA KADA KIMN KAM KDNI KN1 KIMA***
751 .3 .7 1.07 1.05 1.05 1.07 1.07 1.07 1.05 1.07
END NIT-FSTGEN
NIT-FSTPM
*** NITROGEN FIRST-ORDER RATES FOR SURFACE LAYER (/DAY)
# #*** KDSAM KADAM KIMNI KAM KDNI KNI KIMAM
115
-------
751 .0 .005 .0 7. 0.0
END NIT-FSTPM
NIT-FSTPM
*** NITROGEN FIRST-ORDER RATES FOR UPPER LAYER (/DAY)
# #*** KDSAM KADAM KIMNI KAM KDNI KNI KIMAM
751 .0 .0042 0.2 10. ' 0.0
END NIT-FSTPM
NIT-FSTPM
*** NITROGEN FIRST-ORDER RATES FOR LOWER LAYER (/DAY)
# #*** KDSAM KADAM KIMNI KAM KDNI KNI KIMAM
751 .0 .0035 0.2 6. .0
END NIT-FSTPM
NIT-FSTPM
*** NITROGEN FIRST-ORDER RATES FOR GROUNDWATER LAYER (/DAY)
# #*** KDSAM KADAM KIMNI KAM KDNI KNI KIMAM
751 .0 .00037 0.1 6. .0
END NIT-FSTPM
NIT-CMAX
MAXIMUM SOLUBILITY OF AMMONIUM ***
# # CMAX ***
(PPM) ***
751 5000.
END NIT-CMAX
NIT-SVALPM SURFACE
NITROGEN SINGLE VALUE FREUNDLICH ADSORPTION/DESORPTION PARAMTERS ***
XFIX K1 N1***
# # (PPM) ***
751 2. 1.0 1.50
END NIT-SVALPM
NIT-SVALPM UPPER
NITROGEN SINGLE VALUE FREUNDLICH ADSORPTION/DESORPTION PARAMETERS ***
XFIX K1 N1***
# # (PPM) ***
751 2. 1.0 1.20
END NIT-SVALPM
NIT-SVALPM LOWER
NITROGEN SINGLE VALUE FREUNDLICH ADSORPTOIN/DESORPTION PARAMETERS ***
XFIX K1 N1***
# # (PPM) ***
751 .55 0.5 1.20
END NIT-SVALPM
NIT-SVALPM GROUNDWATER
NITROGEN SINGLE VALUE FREUNDLICH ADSORPTION/DESORPTION PARAMETERS ***
XFIX K1 N1***
# # (PPM) ***
751 .25 0.5 1.10
END NIT-SVALPM
NIT-STOR1 SURFACE-BLK 1
INITIAL STORAGE OF N FORMS IN SURFACE LAYER LB/AC ***
# # LORGN AMAD AMSU N03 PLTN RORGN ***
751 50. .25 0.0 .1 50. 200.
END NIT-STOR1
NIT-STOR1 UPPER -BLK 1
IN1TIAL STORAGE OF N FORMS IN UPPER LAYER LB/AC ***
# # LORGN AMAD AMSU N03 PLTN RORGN ***
751 400. 9.0 .05 1.0 300. 1500.
END NIT-STOR1
NIT-STOR1 LOWER LAYER
116
-------
INITIAL STORAGE OF N FORMS IN LOWER LAYER LB/AC ***
# # LORGN AMAD AMSU N03 PLTN RORGN ***
751 150. 8.0 .01 .5 100. 600.
END NIT-STOR1
NIT-STOR1 GROUNDWATER LAYER
INITIAL STORAGE OF N FORMS IN GROUNDWATER LAYER LB/AC ***
# # LORGN AMAD AMSU N03 PLTN RORGN ***
751 100. 5.5 0.1 .1 .0 500.
END NIT-STOR1
NIT-STOR2
INITIAL N IN INTERFLOW, ABOVE GROUND, AND LITTER STORAGE (LB/AC) ***
# # IAMSU IN03 ISLON ISRON AGPLTN LITTRN***
751 350. 30.
END NIT-STOR2
*** SECTION PHOS ***
*** TABLE SOIL-DATA NOT NEEDED AS NITR IS ACTIVE
PHOS-FLAGS
PHOSPHORUS FLAGS ***
VPUT FORP ITMX BMUM CNUM PUPT ***
# - # ***
751 1 100 3 1 1
END PHOS-FLAGS
PHOS-AD-FLAGS
Atmospheric Deposition Flags ***
P04 ORGP ***
sur upp sur upp ***
# - # F C F C F C F C ***
751 -1000-1000
END PHOS-AD-FLAGS
MON-PHOSUPT
PLANT UPTAKE OF PHOSPHORUS IN SURFACE LAYER (/DAY) ***
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
751 .25 .25 .25 .25 .35 1.5 1.5 1.5 1.5 1.2 .25 .25
END MON-PHOSUPT
MON-PHOSUPT
PLANT UPTAKE OF PHOSPHORUS IN UPPER LAYER (/DAY) ***
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
751 .25 .25 .25 .25 .75 3.5 4.5 4.5 4.5 4.5 .55 .25
END MON-PHOSUPT
MON-PHOSUPT
PLANT UPTAKE OF PHOSPHORUS IN LOWER LAYER (/DAY) ***
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
751 .15 .15 .15 .50 2.0 5.2 6.0 6.0 6.0 6.0 .15 .15
END MON-PHOSUPT
*** DEFAULT PLANT UPTAKE OF PHOSPHORUS FROM GROUNDWATER ZONE TO ZERO
PHOS-YIELD
PUPTGT PMXRAT ***
# - # (LB/AC) ***
751 28.00 1.8
END PHOS-YIELD
MON-PUPT-FR1
Monthly fractions for plant uptake target ***
# - # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
751 .01 .04 .09 .115 .135 .145 .15 .14 .095 .05 .025 .005
END MON-PUPT-FR1
117
-------
MON-PUPT-FR2
Monthly fractions for plant uptake target from surface
# - # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC
751 .05 .05 .05 .05 .05 .05 .05 .05 .05 .05 .05 .05
END MON-PUPT-FR2
***
***
MON-PUPT-FR2
Monthly fractions for plant uptake target from upper
# - # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC
751 .85 .85 .85 .85 .85 .85 .85 .85 .85 .85 .85 .85
END MON-PUPT-FR2
***
***
MON-PUPT-FR2
Monthly fractions for plant uptake target from lower ***
# - # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
751 .10 .10 .10 .10 .10 .10 .10 .10 '.10 .10 .10 .10
END MON-PUPT-FR2
MON-PUPT-FR2
Monthly fractions for plant uptake target from active gw ***
# - # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
751 .0 .0 .0 .0 .0 .0 .0 .0 .0 .0 .0 .0
END MON-PUPT-FR2
PHOS-FSTGEN
TEMPERATURE CORRECTION PARAMETERS FOR PHOSPHORUS REACTIONS ***
# # THPLP THKDSP THKADP THKIMP THKMP ***
751 1.07 1.07 1.05
END PHOS-FSTGEN
PHOS-FSTPM
PHOSPHORUS FIRST-ORDER RATES FOR SURFACE LAYER (/DAY)
# # KDSP KADP KIMP KMP
751 10.0 .001
END PHOS-FSTPM
***
***
PHOS-FSTPM
PHOSPHORUS FIRST-ORDER RATES FOR UPPER LAYER (/DAY)
# # KDSP KADP KIMP KMP
751 2.00 .00005
END PHOS-FSTPM
***
***
PHOS-FSTPM
PHOSPHORUS FIRST-ORDER RATES FOR LOWER LAYER (/DAY)
# # KDSP KADP KIMP KMP
751 .100 .00007
END PHOS-FSTPM
***
***
PHOS-FSTPM
PHOSPHORUS FIRST-ORDER RATES FOR GROUNDWATER LAYER (/DAY)
# # KDSP KADP KIMP KMP
751 0. 0.00
END PHOS-FSTPM
***
***
PHOS-CMAX
MAXIMUM SOLUBILITY OF PHOSPHATE ***
# # CMAX ***
(PPM) ***
751 50.0
END PHOS-CMAX
PHOS-SVALPM
XFIX
# # (PPM)
751 20.
END PHOS-SVALPM
PHOS-SVALPM
XFIX
SURFACE
K1
5.
UPPER
K1
N1***
***
1.50
N1***
118
-------
# # (PPM) *
751 15. 5. 1.50
END PHOS-SVALPM
PHOS-SVALPM
XFIX
# # (PPM)
751 10.
END PHOS-SVALPM
PHOS-SVALPM
XFIX
# # (PPM)
751 12.
END PHOS-SVALPM
LOWER
K1
5.
GROUNDWATER
K1
6.
N1***
***
1.50
N1***
***
1.50
fALPM
PHOS-STOR1
INITIAL PHOSPHORUS STORAGE IN SURFACE LAYER LB/AC ***
# # ORGP P4AD P4SU PLTP ***
751 50. 2.00 0.00 0.
END PHOS-STOR1
PHOS-STOR1
INITIAL PHOSPHORUS STORAGE IN UPPER LAYER LB/AC ***
# # ORGP P4AD P4SU PLTP ***
751 100. 28.0 1.00 0.
END PHOS-STOR1
PHOS-STOR1
INITIAL PHOSPHORUS STORAGE IN LOWER LAYER LB/AC ***
# # ORGP P4AD P4SU PLTP ***
751 60. 138.0 1.5 0.
END PHOS-STOR1
PHOS-STOR1
INITIAL PHOSPHORUS STORAGE IN GROUNDWATER LAYER LB/AC ***
# # ORGP P4AD P4SU PLTP ***
751 30. 210. 01.0 0.
END PHOS-STOR1
*** INTERFLOW STORAGES DEFAULTED TO ZERO
END PERLND
RCHRES
ACTIVITY
RCHRES Active Sections (1=Active; 0=Inactive) ***
# - # HYFG ADFG CNFG HTFG SDFG GQFG OXFG NUFG PKFG PHFG ***
750 1101101110
END ACTIVITY
PRINT-INFO
RCHRES Print-flags ***
# - # HYDR ADCA CONS HEAT SED GQL OXRX NUTR PLNK PHCB PIVL PYR ***
750 55 55 555 12
END PRINT-INFO
GEN-INFO
RCHRES< Name >Nexit Unit Systems Printer ***
# - # User t-series Engl Metr LKFG ***
in out ***
750 REACH 750 1 1 1 1 90 0 0
END GEN-INFO
HYDR-PARM1
RCHRES Flags for HYDR section ***
# - # VC A1 A2 A3 ODFVFG for each ODGTFG for each *** FUNCT for each
FG FG FG FG possible exit possible exit *** possible exit
12345 12345*** 12345
750 1114
119
-------
END HYDR-PARM1
HYDR-PARM2
RCHRES
# # FTABNO
750 750
END HYDR-PARM2
LEN
1.0
DELTH
100.0
STCOR
KS
.5
***
DB50 ***
HYDR-INIT
RCHRES Initial conditions for HYDR section ***
# - # VOL Initial value of COLIND *** Initial value of OUTDGT
(ac-ft) for each possible exit *** for each possible exit
EX1 EX2 EX3 EX4 EX5 *** EX1 EX2 EX3 EX4 EX5
750 5.00
END HYDR-INIT
HEAT-PARM
RCHRES ELEV
# - #
750 280.
END HEAT-PARM
ELDAT
-10.
CFSAEX
.95
KATRAD
9.5
KCOND
6.12
KEVAP ***
***
2.24
HEAT-INIT
RCHRES
# - #
750
END HEAT-INIT
TW
33.
AIRTMP ***
***
33.
SANDFG
RCHRES ***
# - tfSNDFG ***
750 3
END SANDFG
SED-GENPARM
RCHRES BEDWID BEDWRN POR ***
# - # (ft) (ft) (-) ***
750 200. 3. 0.4
END SED-GENPARM
SAND-PM
RCHRES
# - #
750
END SAND-PM
D
(in)
.005
W
(in/s)
0.25
RHO
(9/cm3)
2.5
KSAND
.001
EXPSND ***
***
5.0
SILT-CLAY-PM
RCHRES D W
# - # (in) (in/s)
750 0.00040 0.0030
END SILT-CLAY-PM
SILT PARAMETERS
RHO TAUCD TAUCS
(9/cm3)
2.4 0.08 .42
M ***
***
1.8
SILT-CLAY-PM
RCHRES D W
# - it (in) (in/s)
750 0.00010 0.00010
END SILT-CLAY-PM
CLAY PARAMETERS
RHO TAUCD TAUCS
(g/cm3)
2.4 0.070 .40
***
***
2.0
SSED-INIT
RCHRES Suspended sed cones (mg/l) ***
# - # Sand Silt Clay ***
750 0. 8. 8.
END SSED-INIT
BED-INIT
RCHRES BEDDEP
# - # (ft)
750 1.
END BED-INIT
Initial bed composition
Sand Silt Clay
.38 .45 .17
120
-------
BENTH-FLAG
RCHRES BENF ***
# - # ***
750 1
END BENTH-FLAG
OX-FLAGS
RCHRES REAM ***
# - # ***
750 3
END OX-FLAGS
OX-GENPARM
RCHRES KBOD20
# - # /hr
750 .004
END OX-GENPARM
OX-REAPARM
***** REAK= .484*1.
RCHRES TCGINV
# - #
750 1.024
END OX-REAPARM
OX-BENPARM
RCHRES BENOD
# - #
750 100.
END OX-BENPARM
OX-INIT
RCHRES DOX
# - # mg/l
750 14.5
END OX-INIT
NUT-FLAGS
RCHRES TAM N02
# - #
750 1 0
END NUT- FLAGS
TCBOD
1.047
5 (SEE HSPQ
REAK
/hr
.25
TCBEN
1.074
BOD
mg/l
1.3
P04 AMV
1 0
KODSET SUPSAT ***
***
.025 ' 1.15
pg. 54; HSPF pg. 298) *****
EXPRED EXPREV ***
***
-1.673 .969
EXPOD BRBOD(A) BRBOD(2) EXPREL***
mg/in2.hr mg/m2.hr ***
1.22 .001 .001 2.82
SATDO ***
mg/l ***
14.5
DEN ADNH ADPO PHFG ***
***
1 1 1
NUT-AD-FLAGS
Atmospheric Deposition Flags ***
N03 NH3 P04 ***
x -
750 -10-1
END NUT-AD-FLAGS
00
CONV-VAL1
RCHRES
# - #
750 1.63
END CONV-VAL1
CVBO CVBPC CVBPN
mg/mg mo Is/mo I mo Is/mo I
106.
16.
BPCNTC ***
***
49.
NUT-NITDENIT
RCHRES KTAM20 KN0220 TCNIT KN0320 TCDEN DENOXT ***
# - # /hr /hr /hr mg/l ***
750 .018 .012 1.070 .004 1.04 9.0
END NUT-NITDENIT
NUT-BEDCONC
RCHRES Bed concentrations of NH4 & P04 (mg/kg) ***
#- # NH4-sand NH4-silt NH4-clay P04-sand P04-silt P04-clay ***
750 40. 100. 100. 100. 250. 250.
END NUT-BEDCONC
NUT-ADSPARM
121
-------
RCHRES Partition coefficients for NH4 AND P04 (ml/g) ***
# - # NH4-sand NH4-silt NH4-clay P04-sand P04-silt P04-clay ***
750 10. 100. 100. 100. 1000. 1000.
END NUT-ADSPARM
NUT-DINIT
RCHRES N03 TAM
# - # mg/l mg/l
750 2.30 0.10
END NUT-DINIT
N02
mg/l
P04
mg/l
0.05
PH ***
***
7.
NUT-ADSINIT
RCHRES Initial suspended NH4 and P04 concentrations (mg/kg) ***
# - # NH4-sand NH4-silt NH4-clay P04-sand P04-sitt P04-clay ***
750 0. 0. 0. 0. 0. 0.
END NUT-ADSINIT
PLNK- FLAGS
RCHRES PHYF ZOOF BALF SDLT AMRF DECF NSFG ZFOO ***
# - # ***
750 10100112
END PLNK- FLAGS
PINK-AD- FLAGS
Atmospheric Deposition Flags ***
ORN ORP ORC ***
x - :
750 -1000
END PLNK-AD-FLAGS
BENAL-PARM
00
RCHRES MBAL
# - # mg/m2
750 3500.
END BENAL-PARM
PLNK-PARM1
RCHRES RATCLP
# - #
750 .68
END PLNK-PARM1
PLNK-PARM2
RCHRES *** CMMLT
# - # ***ly/min
750 .010
END PLNK-PARM2
PLNK-PARM3
RCHRES ALR20
# - # /hr
750 .005
END PLNK-PARM3
PHYTO-PARM
RCHRES SEED
# - # mg/l
750 1.0
END PHYTO-PARM
PLNK-INIT
RCHRES PHYTO
# - # mg/l
750 0.1
END PLNK-INIT
CFBALR
.5
NONREF
.5
CMMN
mg/l
.025
ALDH
/hr
.01
MXSTAY
mg/l
2.0
ZOO
org/l
.03
CFBALG
1.0
LITSED
0.
CMMNP
mg/l
.0001
ALDL
/hr
.001
OREF
200.
BENAL
mg/m2
3500.
***
***
ALNPR
.25
CMMP
mg/l
.005
OXALD
/hr
.03
CLALDH
ug/l
35.
ORN
mg/l
0.5
EXTB
/ft
0.300
TALGRH
deg F
95.
NALDH
mg/l
.01
PHYSET
.027
ORP
mg/l
0.1
MALGR ***
/hr ***
.110
TALGRL TALGRM
deg F deg F
-10.0 86.
PALDH ***
mg/l ***
.002
REFSET ***
***
.037
ORC ***
mg/l ***
0.5
END RCHRES
*** RCH LENGTH 1 MILE, UPSTREAM ELEV 1400, DOWNSTREAM 1030 FT ***
122
-------
FTABLES
FTABLE 750
ROWS COLS ***
15 4
DEPTH AREA VOLUME DISCH FLO-THRU ***
(FT) (ACRES) (AC-FT) (CFS) (MIN) ***
0.00 0.0 0.0 0.0 0.
0.42 2.0 0.8 30.7 19.
0.83 2.1 1.6 98.2 12.
1.25 2.3 2.6 194.8 10.
1.67 2.4 3.5 318.2 8.
2.08 2.6 4.6 467.3 7.
2.50 2.7 5.7 641.9 6.
3.33 3.0 8.1 1067. 5.
4.17 3.3 10.7 1597. 5.
5.00 3.6 13.6 2233. 4.
6.67 5.6 21.3 4177. 4.
8.33 7.5 32.2 6791. 3.
10.00 9.5 46.4 10183. 3.
11.67 11.4 63.8 14445. 3.
13.33 13.3 84.4 19662. 3.
END FTABLE750
END FTABLES
EXT SOURCES
<-Volume-> SsysSgap<--Mutt-->Tran <-Target vols>
# # tem strg<-factor->strg # #
WDM 203 HPRC 10 ENGLZERO 1.05 SAME PERLND 751
WDM 50 EVAP ENGLZERO 0.78 DIV PERLND 751
WDM 51 DEWP ENGLZERO SAME PERLND 751
WDM 54 WNDH ENGLZERO SAME PERLND 751
WDM 56 RADH ENGLZERO SAME PERLND 751
WDM 310 TEMP ENGLZERO SAME PERLND 751
WDM 203 HPRC 10 ENGLZERO 1.05 SAME RCHRES 750
WDM 50 EVAP ENGLZERO 0.78 DIV RCHRES 750
WDM 51 DEWP ENGLZERO SAME RCHRES 750
WDM 52 CLDC ENGLZERO SAME RCHRES 750
WDM 54 WNDH ENGLZERO SAME RCHRES 750
WDM 56 RADH ENGLZERO SAME RCHRES 750
WDM 310 TEMP ENGLZERO SAME RCHRES 750
*** ATMOSPHERIC DEPOSITION LOADS
WDM 571 NH4X ENGL DIV PERLND 751
WDM 572 N03X ENGL DIV PERLND 751
WDM 573 N03X ENGL DIV PERLND 751
WDM 575 ORGN ENGL DIV PERLND 751
WDM 571 NH4X ENGL DIV RCHRES 750
WDM 572 N03X ENGL DIV RCHRES 750
WDM 573 N03X ENGL DIV RCHRES 750
WDM 575 ORGN ENGL DIV RCHRES 750
END EXT SOURCES
SCHEMATIC
<-Grp> <-Member-> ***
# # ***
EXTNL PREC
EXTNL PETINP
EXTNL DTMPG
EXTNL WINMOV
EXTNL SOLRAD
EXTNL GATMP
EXTNL PREC
EXTNL POTEV
EXTNL DEWTMP
EXTNL CLOUD
EXTNL WIND
EXTNL SOLRAD
EXTNL GATMP
EXTNL NIADFX 2 1
EXTNL NIADFX 1 1
EXTNL NIADFX 1 1
EXTNL NIADFX 3 1
EXTNL NUADFX 2 1
EXTNL NUADFX 1 1
EXTNL NUADFX 1 1
EXTNL PLADFX 1 1
<-Source-> <--Area--> <-Target-> ***
# <-factor-> #
PERLND 751 2567. RCHRES 750
PERLND 751 2567. COPY 600
END SCHEMATIC
MASS- LINK
# ***
1
91
MASS-LINK 1
<-Grp> <-Member-><--Mult-->
# #<-factor->
PERLND PWATER PERO 0.0833333 RCHRES
<-Grp> <-Member-> ***
# # ***
INFLOW IVOL
123
-------
PERLND SEDMNT
PERLND SEDMNT
PERLND SEDMNT
PERLND PUTGAS
PERLND PWTGAS
PERLND NITR
PERLND NITR
PERLND NITR
PERLND NITR
PERLND NITR
PERLND NITR
PERLND NITR
END MASS- LINK
MASS- LINK
<-Volume-> <-Grp>
PERLND PUATER
PERLND PUATER
PERLND PUATER
PERLND PUATER
PERLND PUATER
PERLND PUATER
PERLND PWATER
END MASS-LINK
END MASS- LINK
NETUORK
<-Volume-> <-Grp>
#
PERLND 751 NITR
PERLND
GENER
PERLND
PERLND
GENER
PERLND
PERLND
GENER
751
1
751
751
2
751
751
3
PUATER
OUTPUT
NITR
PWATER
OUTPUT
NITR
PUATER
OUTPUT
**** PARTICULATE
RCHRES
RCHRES
GENER
RCHRES
750
750
4
750
**** TOTAL
RCHRES
RCHRES
GENER
RCHRES
750
750
4
750
*** TOTAL
RCHRES
RCHRES
750
750
*** TOTAL
RCHRES
RCHRES
RCHRES
RCHRES
PERLND
PERLND
PERLND
750
750
750
750
751
751
751
NUTRX
HYDR
OUTPUT
PLANK
N
NUTRX
NUTRX
OUTPUT
PLANK
SOSED 1 0.04
SOSED 1 0.69
SOSED 1 0.27
POHT
PODOXM
PON03
TSAMS 1
TSAMS 5
SSAMS 3
SEDN 2 0.70
SEDN 2 0.30
SEDN 1
1
91
<-Member-><--Mult-->Tran
x x<-factor->strg
SURO
IFUO
AGUO
PET
TAET
UZS
LZS
91
<-Member-><--Mult-->Tran
# #<-factor->strg
PON03
PERO
TIMSER
PONH4
PERO
TIMSER
POORN
PERO
TIMSER
N (ADS
RSNH4
VOL
TIMSER
PKST3
DNUST
DNUST
TIMSER
PKST3
NH3 (DISS NH3
NUTRX
NUTRX
NUCF1
NUCF2
NH3
4
4
1
2
4
0.0833
0.368
0.0833
0.368
0.0833
0.368
+ ORG N)
0.368
0.368
SAME
SAME
SAME
AVER
AVER
SAME
AVER
AVER
AVER
SAME
AVER
+ ADS NH3) LOADING
2
4
N LOADING - N03 +
NUTRX
NUTRX
NUTRX
PLANK
NITR
NITR
NITR
NUCF1
NUCF1
NUCF2
PKCF1
SN
UN
LN
1
2
4
3
5
5
5
1
NH3 + ORN
1
***
RCHRES INFLOU
RCHRES INFLOU
RCHRES INFLOU
RCHRES INFLOU
RCHRES INFLOU
RCHRES INFLOU
RCHRES INFLOU
RCHRES INFLOU
RCHRES INFLOU
RCHRES INFLOU
RCHRES INFLOU
RCHRES INFLOU
<-Target vols> <-Grp>
COPY INPUT
COPY INPUT
COPY INPUT
COPY INPUT
COPY INPUT
COPY INPUT
COPY INPUT
<-Target vols> <-Grp>
# #
GENER 1 INPUT
GENER
COPY
GENER
GENER
COPY
GENER
GENER
COPY
GENER
GENER
COPY
COPY
COPY
COPY
COPY
COPY
***
COPY
COPY
COPY
COPY
COPY
COPY
COPY
COPY
COPY
1
1
2
2
1
3
3
1
4
4
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
INPUT
INPUT
INPUT
INPUT
INPUT
INPUT
INPUT
INPUT
INPUT
INPUT
INPUT
INPUT
INPUT
INPUT
INPUT
INPUT
INPUT
INPUT
INPUT
INPUT
INPUT
INPUT
INPUT
INPUT
INPUT
ISED 1
ISED 2
ISED 3
I HEAT
OXIF 1
NUIF1 1
NUIF1 2
NUIF1 2
NUIF1 2
NUIF2 2 1
NUIF2 3 1
PKIF 3
<-Member-> ***
x x ***
MEAN 1
MEAN 2
MEAN 3
MEAN 4
MEAN 5
MEAN 6
MEAN 7
<-Member-> ***
# # ***
ONE
TUO
MEAN
ONE
TUO
MEAN
ONE
TUO
MEAN
ONE
TUO
MEAN
MEAN
MEAN
MEAN
MEAN
MEAN
MEAN
MEAN
MEAN
MEAN
MEAN
MEAN
POINT
POINT
POINT
1
2
3
***
***
1 ***
1 ***
2 ***
2 ***
2 ***
2 ***
6 ***
6 ***
7 ***
7 ***
7 ***
7 ***
1
1
1
124
-------
PERLND 751 NITR AN
COPY
INPUT POINT 1
END NETWORK
EXT TARGETS
<-Volume-> <-Grp> <-Member-><--Mult-->Tran <-Volume-> Tsys Tgap Amd ***
# # #<-factor->strg # # tern strg strg***
RCHRES 750 HYDR RO AVER WDM 1701 FLOW ENGL AGGR REPL
PERLND 751 SNOW PDEPTH AVER WDM 1717 SNOW ENGL AGGR REPL
PERLND 751 PWATER PERO 2566.4 AVER WDM 1702 SEDM ENGL AGGR REPL
***Expert System Data Sets
COPY 600 OUTPUT MEAN 1
COPY 600 OUTPUT MEAN 2
COPY 600 OUTPUT MEAN 3
COPY 600 OUTPUT MEAN 4
COPY 600 OUTPUT MEAN 5
COPY 600 OUTPUT MEAN 6
COPY 600 OUTPUT MEAN 7
RCHRES 750 ROFLOW ROVOL
COPY 1 OUTPUT MEAN 1
COPY 1 OUTPUT MEAN 2
COPY 1 OUTPUT MEAN 3
PERLND 751 NITR AGPLTN
COPY 1 OUTPUT POINT 1
PERLND 751 NITR LITTRN
PERLND 751 NITR TOTNIT
PERLND 751 NITR TN 5
PERLND 751 PWATER PERO
PERLND 751 NITR TN 1
PERLND 751 NITR TN 7
GENER 751 OUTPUT TIMSER
PERLND 751 NITR SN 3
PERLND 751 NITR UN 3
PERLND 751 NITR LN 3
PERLND 751 NITR AN 3
PERLND 751 NITR TN 3
PERLND 751 NITR SN 4
PERLND 751 NITR UN 4
PERLND 751 NITR LN 4
PERLND 751 NITR AN 4
PERLND 751 NITR TN 4
RCHRES 750 NUTRX DNUST 1
RCHRES 750 NUTRX DNUST 2
COPY 1 OUTPUT MEAN 1
COPY 1 OUTPUT MEAN 2
RCHRES 750 PLANK PHYCLA
RCHRES 750 PLANK PKST3 6
RCHRES 750 OXRX DOX
RCHRES 750 OXRX BOD
RCHRES 750 HTRCH TW
PERLND 751 PSTEMP SLTMP
PERLND 751 PSTEMP ULTMP
PERLND 751 PSTEMP LGTMP
to WDM***
.000389559 WDM
.000389559 WDM
.000389559 WDM
.000389559 WDM
.000389559 WDM
.000389559 WDM
.000389559 WDM
.00467471 WDM
AVER WDM
AVER WDM
AVER WDM
AVER WDM
AVER WDM
AVER WDM
AVER WDM
AVER WDM
AVER WDM
AVER WDM
AVER WDM
SUM WDM
AVER WDM
AVER WDM
AVER WDM
AVER WDM
AVER WDM
AVER WDM
AVER WDM
AVER WDM
AVER WDM
AVER WDM
AVER WDM
AVER WDM
AVER WDM
AVER WDM
AVER WDM
AVER WDM
AVER WDM
AVER WDM
AVER WDM
AVER WDM
AVER WDM
AVER WDM
401 SURO
402 IFWO
403 AGWO
404 PETX
405 SAET
406 UZST
407 LZST
408 QDEP
2004 N03X
2005 NH3X
2006 ORGN
2007 NITR
2022 NITR
2008 NITR
2009 NITR
2010 NITR
2011 PERO
2023 NITR
2024 NITR
2025 NITR
2012 NITR
2013 NITR
2014 NITR
2015 NITR
2016 NITR
2017 NITR
2018 NITR
2019 NITR
2020 NITR
2021 NITR
1706 N03X
1705 NH4X
1707 ORGN
1708 TOTN
1713 CHLA
1712 TOCX
1704 DOXX
1714 BODX
1703 WTMP
2001 STMP
2002 UTMP
2003 LTMP
ENGL AGGR REPL
ENGL AGGR REPL
ENGL AGGR REPL
ENGL AGGR REPL
ENGL AGGR REPL
ENGL AGGR REPL
ENGL AGGR REPL
ENGL AGGR REPL
ENGL AGGR REPL
ENGL AGGR REPL
ENGL AGGR REPL
ENGL AGGR REPL
ENGL AGGR REPL
ENGL AGGR REPL
ENGL AGGR REPL
ENGL AGGR REPL
ENGL AGGR REPL
ENGL AGGR REPL
ENGL AGGR REPL
ENGL AGGR REPL
ENGL AGGR REPL
ENGL AGGR REPL
ENGL AGGR REPL
ENGL AGGR REPL
ENGL AGGR REPL
ENGL AGGR REPL
ENGL AGGR REPL
ENGL AGGR REPL
ENGL AGGR REPL
ENGL AGGR REPL
ENGL AGGR REPL***
ENGL AGGR REPL***
ENGL AGGR REPL***
ENGL AGGR REPL***
ENGL AGGR REPL***
ENGL AGGR REPL***
ENGL AGGR REPL***
ENGL AGGR REPL***
METR AGGR REPL***
ENGL AGGR REPL
ENGL AGGR REPL
ENGL AGGR REPL
END EXT TARGETS
GENER
OPCODE
#thru# code ***
1 4 19
751 24
END OPCODE
125
-------
PARM
#thru# constant ***
751 0
END PARM
END GENER
COPY
TIMESERIES
#thru# NPT NMN ***
1 1 3
600 7
END TIMESERIES
END COPY
END RUN
126
-------
Appendix E. Young Womans Creek UCI
127
-------
RUN
GLOBAL
YOUNG WOMAN'S CREEK AT RENOVO, PA 9103-25 - FOREST N TESTING RUN# 31
START 1984/01/01 END 1991/12/31
RUN INTERP OUTPUT LEVEL 4
RESUME 0 RUN 1
END GLOBAL
FILES
UDM
MESSU
END
***< FILE NAME
24 \usgs\9103-25\wdm\renovo.wdm
25 renovo.ech
90 renovo.out
FILES
OPN SEQUENCE
INGRP
PERLND
RCHRES
COPY
GENER
GENER
GENER
GENER
GENER
COPY
END INGRP
END OPN SEQUENCE
INDELT 01:00
61
60
600 ***
1
2
3
4
61
1
SPEC-ACTIONS
*** kwd varnam optyp opn van" s1 s2 s3 tp multiply Ic Is ac as agfn ***
<****> < > < > <-> < ><-><-><-><->< > <><-> <><-> <--> ***
UVQUAN ornmin PERLND 61 ORNMN 5 3
*** dstp
GENER 61 3
END SPEC-ACTIONS
<1><2><3><-value--> tc tst nu
K 1 = ornmin
PERLND
ACTIVITY
# # ATMP SNOW PWAT SED PST
61 11111
END ACTIVITY
PRINT-INFO
# # ATMP SNOW PWAT SED PST
61 55555
END PRINT-INFO
PWG PQAL MSTL PEST NITR PHOS TRAC
1010100
PWG PQAL MSTL PEST NITR PHOS TRAC PIVL***PY
55505000 12
GEN-INFO
# # NAME NBLKS UCI IN
61 FOREST 1 1 1
END GEN-INFO
OUT ENGL METR ***
1 90 0
ATEMP-DAT
ELEVATION DIFFERENCE BETWEEN GAGE AND PLS ***
ELDAT AIRTMP ***
# # (ft) (deg F) ***
61 876.0 24.4
END ATEMP-DAT
ICE-FLAG
# # I CFG ***
61 1
END ICE-FLAG
SNOW-PARM1
LAT
ELEV
SHADE
SNOWCF COVIND ***
128
-------
# # (DEC)
61 41. 4
END SNOU-PARM1
SNOU-PARM2
# # RDCSN
61 0.120
END SNOU-PARM2
SNOU-INIT1
# # PACK- SNOW
61 1.500
END SNOW-INIT1
SNOW- IN I T2
# # COVINX
61 0.01
END SNOW-INIT2
PWAT-PARM1
(FT)
1400.
TSNOW
32.0
0.80
SNOEVP
0.150
PACK-ICE PACK-WATR
0.000
XLNMLT
0.0
# # CSNO RTOP UZFG VCS
61 1 1
END PWAT-PARM1
PUAT-PARM2
# # ***FOREST
61 0.300
END PWAT-PARM2
PWAT-PARH3
# # ***PETMAX
61 35.0
END PWAT-PARM3
PUAT-PARM4
# # CEPSC
61 0.00
END PWAT-PARM4
MON-INTERCEP
# # JAN FEB
61 0.0500.0500
END MON-INTERCEP
MON-LZETPARM
# # JAN FEB
61 0.2 0.2
END MON-LZETPARM
MON-UZSN
# # JAN FEB
61 0.8 0.8
END MON-UZSN
PWAT-STATE1
if # *** CEPS
61 0.000
END PWAT- STATE 1
SED-PARM1
# # CRV VSIV
61 1 0
END SED-PARM1
SED-PARM2
# # SMPF
61 1.000
1 1
LZSN
3.500
PETMIN
30.0
UZSN
0.800
MAR APR
.0500.1000
MAR APR
0.30 0.45
MAR APR
0.8 0.9
SURS
0.000
SDOP ***
1
KRER
0.200
0.150
SKYCLR"
0.90
VUZ NVV
1 0
INFILT
0.0500
INFEXP
2.0
NSUR
0.350
MAY JUN
.1600 .20
MAY JUN
0.55 0.60
MAY JUN
1.0 1.1
UZS
0.8
JRER
2.000
1.20
CCFACT
1.000
RDENPF
0.20
***
VIFW VIRC
0 0
LSUR
200.
INFILD
2.0
INTFW
8.000
JUL AUG
.20 .20
JUL AUG
0.60 0.60
JUL AUG
1.2 1.2
IFWS
0.000
AFFIX
0.002
(IN)
0.3
MWATER
0.030
DULL
400.
VLB ***
1
SLSUR
0; 22000
DEEPFR
0.0
IRC
0.850
SEP OCT
.20 .15
SEP OCT
0.60 0.50
SEP OCT
1.2 1.2
LZS
4.0
-
COVER
0.000
***
MGMELT
0.015
PAKTMP
30.0
KVARY
1.000
BASETP
0.000
LZETP
0.400
NOV DEC
.0500.050
NOV DEC
.35 0.2
NOV DEC
1.2 0.9
AGUS
0.50
NVSI
2.000
***
***
AGWR
0.975
AGWETP
0.0
***
***
***
***
GWVS
0.70
***
END SED-PARM2
129
-------
SED-PARM3
# # KSER JSER KGER JGER ***
61 0.190 2.000 0.000 2.000
END SED-PARM3
MON-COVER
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
61 0.97 0.97 0.97 0.97 0.97 0.97 0.97 0.97 0.97 0.97 0.97 0.97
END MON-COVER
SED-STOR
# # DETS ***
61 0.0500
END SED-STOR
PSTEMP-PARM1
# # SLTV ULTV LGTV TSOP ***
61 1111
END PSTEMP-PARM1
PSTEMP-PARM2
# # ASLT BSLT ULTP1 ULTP2 LGTP1 LGTP2 ***
61 32.0 0.95 32.0 0.90 32.0 0.0
END PSTEMP-PARM2
MON-ASLT
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
61 33. 33. 35. 41. 45. 47. 47. 47. 47. 45. 40. 35.
END MON-ASLT
MON-BSLT
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
61 0.30 0.30 0.35 0.45 0.52 0.55 0.55 0.55 0.55 0.52 0.45 0.42
END MON-BSLT
MON-ULTP1
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
61 36. 36. 37. 40. 43. 45. 45. 45. 45. 43. 40. 38.
END MON-ULTP1
MON-ULTP2
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
61 0.22 0.22 0.25 0.40 0.50 0.52 0.52 0.52 0.52 0.50 0.45 0.25
END MON-ULTP2
MON-LGTP1
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
61 49.0 48.5 50.0 51.0 52.0 53.5 54.5 55.0 54.5 53.5 52.0 49.5
END MON-LGTP1
PSTEMP-TEMPS
# # AIRTC SLTMP ULTMP LGTMP ***
61 32.0 32.0 32.0 50.0
END PSTEMP-TEMPS
PWT-PARM1
# # IDV ICV GDV GCV ***
61 1010
END PWT-PARM1
PWT-PARM2
# # ELEV IDOXP IC02P ADOXP AC02P ***
61 1400. 8.80 0.00 8.80 0.00
END PWT-PARM2
MON-IFWDOX
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
61 14. 14. 13. 12. 11.5 10.5 10. 9.50 9.50 10.5 11.5 12.
END MON-IFUDOX
130
-------
MON-GRNDDOX
# it JAN FEB MAR
61 13.5 13.5 12.5
END MON-GRNDDOX
APR
11.0
MAY
10.5
JUN
10.
JUL
9.5
AUG
9.0
SEP
9.0
OCT
10.
NOV DEC
11.0 12.0
PWT-GASES
# # SODOX SOC02
61 14.5 0.0
END PWT-GASES
IODOX
12.7
IOC02
0.0
AODOX
10.0
AOC02 ***
0.0
*** SECTION MSTLAY *
MST-PARM
FACTORS USED TO ADJUST SOLUTE LEACHING RATES ***
SLMPF ULPF LLPF ***
# # ***
61 0.9 3.0 1.5
END MST-PARM
MST-TOPSTOR
MST-TOPFLX
INITIAL MOISTURE TOP SOIL LAYER STORAGES DEFAULTED TO ZERO ***
INITIAL MOISTURE FLUXES TOP SOIL LAYER DEFAULTED TO ZERO ***
*** SECTION NITR ***
SOIL-DATA
SOIL LAYER DEPTHS AND BULK DENSITIES ***
# - # DEPTHS (IN) BULK DENSITY (LB/FT3) ***
SURFACE UPPER LOWER GROUNDW SURFACE UPPER LOWER GROUNDW
61 0.39 11.42 35.43 60. 78.7 81.8 86.8 88.7
END SOIL-DATA
NIT-FLAGS
NITROGEN FLAGS ***
# - # VNUT FORA ITMX BNUM CNUM NUPT FIXN AMVO ALPN VNPR ***
61 1 1 100 3 1 2 11
END NIT-FLAGS
NIT-AD-FLAGS
Atmospheric Deposition Flags ***
N03
sur upp
# - # F C F C
61 -1000
END NIT-AD-FLAGS
NH3
sur upp
F C F C .
-1000
ORGN ***
sur upp ***
F C F C ***
-1000
NIT-UPIMCSAT
CSUNI
# - # (UG/L)
61 50.
END NIT-UPIMCSAT
SURFACE LAYER
CSUAM CSINI
(UG/L) (UG/L)
5. 10.
CSIAM ***
(UG/L) ***
2.0
NIT-UPIMCSAT
CSUNI
# - # (UG/L)
61 50.
END NIT-UPIMCSAT
UPPER LAYER
CSUAM CSINI
(UG/L) (UG/L)
5. 10.
CSIAM ***
(UG/L) ***
2.0
NIT-UPIMCSAT
CSUNI
# - # (UG/L)
61 50.
END NIT-UPIMCSAT
LOWER LAYER
CSUAM CSINI
(UG/L) (UG/L)
10. 10.
CSIAM ***
(UG/L) ***
2.0
NIT-UPIMCSAT
CSUNI
# - # (UG/L)
61 50.
END NIT-UPIMCSAT
GROUNDWATER LAYER
CSUAM CSINI CSIAM ***
(UG/L) (UG/L) (UG/L) ***
10. 10. 3.0
131
-------
MON-NITUPNI SURFACE LAYER
Maximum Plant Uptake Rate for Nitrate (mg/l/day) ***
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
61 0. 0. 5. 25. 25. 25. 10. 10. 10. 10. 5. 0.
END MON-NITUPNI
MON-NITUPNI UPPER LAYER
Maximum Plant Uptake Rate for Nitrate (mg/l/day) ***
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
61 . 2.0 2.0 10. 50. 70. 70. 50. 50. 50. 30. 5. 2.
END MON-NITUPNI
MON-NITUPNI LOWER LAYER
Maximum Plant Uptake Rate for Nitrate (mg/l/day) ***
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
61 ' .4 .4 .40 3.0 3.0 3.0 2.0 2.0 2.0 1.0 .4 .4
END MON-NITUPNI
MON-NITUPNI GROUND WATER LAYER
Maximum Plant Uptake Rate for Nitrate (mg/l/day) ***
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
61 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0.
END MON-NITUPNI
MON-NITUPAM SURFACE LAYER
Maximum Plant Uptake Rate for Ammonia (mg/l/day) ***
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
61 0. 0. 2.0 15. 15. 15. 12. 12. 12. 8. 2. 0.
END MON-NITUPAM
MON-NITUPAM UPPER LAYER
Maximum Plant Uptake Rate for Ammonia (mg/l/day) ***
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
61 2.0 2.0 20. 50. 70. 70. 50. 50. 50. 30. 10. 2.0
END MON-NITUPAM
MON-NITUPAM LOWER LAYER
Maximum Plant Uptake Rate for Ammonia (mg/l/day) ***
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
61 .4 .4 .40 3.0 3.0 3.0 2.0 2.0 2.0 1.5 .40 .4
END MON-NITUPAM
MON-NITUPAM GROUND WATER LAYER
Maximum Plant Uptake Rate for Ammonia (mg/l/day) ***
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
61 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0.
END MON-NITUPAM
MON-NITIMNI SURFACE LAYER
Maximum Immobilization Rate for Nitrate (mg/l/day) ***
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
61 .10 .10 .10 .20 .20 .20 .30 .30 .20 .20 .20 .10
END MON-NITIMNI
***
MON-NITIMNI UPPER LAYER
Maximum Immobilization Rate for Nitrate (mg/l/day)
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
61 .60 .60 .60 .60 .60 1.2 1.2 1.2 1.2 .60 .60 .60
END MON-NITIMNI
MON-NITIMNI LOWER LAYER
Maximum Immobilization Rate for Nitrate (mg/l/day) ***
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
61 .10 .10 .10 .15 .15 .20 .20 .20 .20 .20 .12 .10
END MON-NITIMNI
MON-NITIMNI GROUNDWATER LAYER
Maximum Immobilization Rate for Nitrate (mg/l/day) ***
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
132
-------
61 .0 .0 .0 .0 .0 .0 .0 .0 .0 .0 .0 .0
END MON-N1TIMNI
MON-NITIMAH SURFACE LAYER
Maximum Immobilization Rate for Ammonia (mg/l/day) ***
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
61 .45 .45 .45 .45 .45 .90 .90 .90 .90 .45 .45 .45
END MON-NITIMAM
MON-NITIMAM UPPER LAYER
Maximum Immobilization Rate for Ammonia (mg/l/day) ***
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
61 1.0 1.0 1.0 1.2 1.2 1.35 1.35 1.35 1.35 1.2 1.2 1.0
END MON-NITIMAM
MON-NITIMAM LOWER LAYER
Maximum Immobilization Rate for Ammonia (mg/l/day) ***
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
61 .12 .12 .12 .18 .20 .20 .20 .20 .20 .18 .18 .12
END MON-NITIMAM
MON-NITIMAM GROUNDWATER LAYER
Maximum Immobilization Rate for Ammonia (mg/l/day) ***
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
61 .15 .15 .15 .15 .15 .30 .30 .30 .30 .15 .15 .15
END MON-NITIMAM
MON-NITAGUTF SURFACE LAYER
Monthly Above-Ground Fractions for Plant Uptake ***
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
61 .3 .3 .3 .7 .7 .7 .7 .4 .4 .4 .4 .3
END MON-NITAGUTF
MON-NITAGUTF UPPER LAYER
Monthly Above-Ground Fractions for Plant Uptake ***
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
61 .3 .3 .3 .7 .7 .7 .7 .4 .4 .4 .4 .3
END MON-NITAGUTF
MON-NITAGUTF LOWER LAYER
Monthly Above-Ground Fractions for Plant Uptake ***
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
61 .3 .3 .3 .7 .7 .7 .7 .4 .4 .4 .4 .3
END MON-NITAGUTF
MON-NITAGUTF GROUNDWATER LAYER
Monthly Above-Ground Fractions for Plant Uptake ***
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
61 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0.
END MON-NITAGUTF
NIT-ORGPM
ORGANIC N TRANSFORMATION PARAMETERS FOR SURFACE LAYER ***
X - X KLON KRON KONLR THNLR ***
61 4000. 30000.0 .0001 1.07
END NIT-ORGPM
NIT-ORGPM
ORGANIC N TRANSFORMATION PARAMETERS FOR UPPER LAYER ***
x - x KLON KRON KONLR THNLR ***
61 4000. 30000.0 .00001 1.07
END NIT-ORGPM
NIT-ORGPM
ORGANIC N TRANSFORMATION PARAMETERS FOR LOWER LAYER ***
x - x KLON KRON KONLR THNLR ***
61 4000. 30000.0 .000010 1.07
END NIT-ORGPM
133
-------
NIT-ORGPM
ORGANIC N TRANSFORMATION PARAMETERS FOR ACTIVE GU LAYER ***
X - x KLON KRON KONLR THNLR ***
61 4000. 30000.0 .000010 1.07
END NIT-ORGPM
MON-NPRETBG SURFACE LAYER
Return rates for below-ground plant N in surface layer (/day) ***
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
61 0. 0. 0. 0. 0. .0. 0. 0. 0. 0. 0. 0.
END MON-NPRETBG
MON-NPRETBG UPPER LAYER
Return rates for below-ground plant N in upper layer ***
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
61 5.E-45.E-45.E-45.E-45.E-45:E-45.E-45.E-45.E-45.E-45.E-45.E-4
END MON-NPRETBG
MON-NPRETBG LOWER LAYER
Return rates for below-ground plant N in lower layer ***
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
61 3.E-43.E-43.E-43.E-43.E-43.E-43.E-43.E-43.E-43.E-43.E-43.E-4
END MON-NPRETBG
MON-NPRETBG GROUNDWATER LAYER
Return rates for below-ground plant N in GW layer ***
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
61 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0.
END MON-NPRETBG
MON-NPRETFBG
Monthly refractory fractions for below-ground plant N return ***
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
61 .05 .05 .05 .05 .05 .05 .05 .05 .05 .05 .05 .05
END MON-NPRETFBG
MON-NPRETAG
Monthly return rates for above-ground plant N to Litter (/day) ***
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
61 0. 0. 0. 0. 0. 0. 0. 0. 0..0012.0004 0.
END MON-NPRETAG
MON-NPRETLI SURFACE LAYER
Monthly return rates for litter N to SZ (/day) ***
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
61 .0007.0007.0007.0007.0007.0007.0007.0007.0007.0007.0007.0007
END MON-NPRETLI
MON-NPRETLI UPPER LAYER
Monthly return rates for litter N to UZ (/day) ***
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
61 .0015.0015.0015.0015.0015.0015.0015.0015.0015.0015.0015.0015
END MON-NPRETLI
MON-NPRETFLI
Monthly refractory fractions for litter N return to SZ/UZ ***
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
61 .05 .05 .05 .05 .05 .05 .05 .05 .05 .05 .05 .05
END MON-NPRETFL!
NIT-FSTGEN
UPT-FRAC.< TEMP-PARMS(THETA) > ***
# # N03 NH4 PLN KDSA KADA KIMN KAM KDNI KNI KIMA ***
61 0.3 0.7 1.07 1.05 1.05 1.07 1.07 1.07 1.05 1.07
END NIT-FSTGEN
NIT-FSTPM
*** NITROGEN FIRST-ORDER RATES FOR SURFACE LAYER (/DAY)
# #*** KDSAM KADAM KIMNI KAM KDNI KNI KIMAM
134
-------
61 .0 .005 0. 7.0 0.0
END NIT-FSTPM
NIT-FSTPM
*** NITROGEN FIRST-ORDER RATES FOR UPPER LAYER (/DAY)
# #*** KDSAM KADAM KIMNI KAM KDNI KNI KIMAM
61 .0 .0037 0.2 10.0 0.0
END NIT-FSTPM
NIT-FSTPM
*** NITROGEN FIRST-ORDER RATES FOR LOWER LAYER (/DAY)
# #*** KDSAM KADAM KIMNI KAM KDNI KNI KIMAM
61 .0 .005 0.1 6.0 0.0
END NIT-FSTPM
WIT-FSTPM
*** NITROGEN FIRST-ORDER RATES FOR GROUNDWATER LAYER (/DAY)
# #*** KDSAM KADAM KIMNI KAM KDNI KNI KIMAM
61 .0 .00039 .10 6.0 0.0
END NIT-FSTPM
NIT-CMAX
MAXIMUM SOLUBILITY OF AMMONIUM ***
# # CMAX ***
(PPM) ***
61 5000.
END NIT-CMAX
NIT-SVALPM SURFACE
NITROGEN SINGLE VALUE FREUNDLICH ADSORPTION/DESORPTION PARAMTERS ***
XFIX K1 N1***
# # (PPM) ***
61 2. 1.0 1.50
END NIT-SVALPM
NIT-SVALPM UPPER
NITROGEN SINGLE VALUE FREUNDLICH ADSORPTION/DESORPTION PARAMETERS ***
XFIX K1 N1***
# # (PPM) ***
61 2. 1.0 1.20
END NIT-SVALPM
NIT-SVALPM LOWER
NITROGEN SINGLE VALUE FREUNDLICH ADSORPTOIN/DESORPTION PARAMETERS ***
XFIX K1 N1***
# # (PPM) ***
61 .55 0.5 1.20
END NIT-SVALPM
NIT-SVALPM GROUNDWATER
NITROGEN SINGLE VALUE FREUNDLICH ADSORPTION/DESORPTION PARAMETERS ***
XFIX K1 N1***
# # (PPM) ***
61 .25 0.5 1.10
END NIT-SVALPM
NIT-STOR1 SURFACE-BLK 1
INITIAL STORAGE OF N FORMS IN SURFACE LAYER LB/AC ***
# # LORGN AMAD AMSU N03 PLTN RORGN***
61 50. .25 0.0 0.05 50. 200.
END NIT-STOR1
NIT-STOR1 UPPER -BLK 1
IN1TIAL STORAGE OF N FORMS IN UPPER LAYER LB/AC ***
# # LORGN AMAD AMSU N03 PLTN RORGN***
61 400. 3.5 0.05 0.2 220. 1500.
END NIT-STOR1
NIT-STOR1 LOWER LAYER
135
-------
INITIAL STORAGE OF N FORMS IN LOWER LAYER LB/AC ***
# # LORGN AMAD AMSU N03 PLTN RORGN***
61 150. 7.0 0.01 0.05 80. 600.
END NIT-STOR1
NIT-STOR1 GROUNDWATER LAYER
INITIAL STORAGE OF N FORMS IN GROUNDWATER LAYER LB/AC ***
# # LORGN AMAD AMSU N03 PLTN RORGN***
61 100. 5.0 0.01 .05 .0 500.
END NIT-STOR1
NIT-STOR2
INITIAL N IN INTERFLOW, ABOVE GROUND, AND LITTER STORAGE (LB/AC) ***
# # IAMSU IN03 ISLON ISRON AGPLTN LITTRN***
61 350. 30.
END NIT-STOR2
*** INTERFLOW STORAGES DEFAULTED TO ZERO
*** SECTION PHOS ***
*** TABLE SOIL-DATA NOT NEEDED AS NITR IS ACTIVE
PHOS-FLAGS
PHOSPHORUS FLAGS ***
VPUT FORP ITMX BMUM CNUM PUPT ***
# - # ***
61 1 100 3 1 1
END PHOS-FLAGS
PHOS-AD-FLAGS
Atmospheric Deposition Flags ***
P03 ORGP ***
sur upp sur upp ***
# - # F C F C F C F C ***
61 -1000-1000
END PHOS-AD-FLAGS
MON-PHOSUPT
PLANT UPTAKE OF PHOSPHORUS IN SURFACE LAYER (/DAY) ***
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
61 .25 .25 .25 .25 .25 .35 .85 .90 .80 .75 .25 .25
END MON-PHOSUPT
MON-PHOSUPT
PLANT UPTAKE OF PHOSPHORUS IN UPPER LAYER (/DAY) ***
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
61 .25 .25 .25 .25 .75 3.5 4.5 4.5 4.5 4.5 .55 .25
END MON-PHOSUPT
MON-PHOSUPT
PLANT UPTAKE OF PHOSPHORUS IN LOWER LAYER (/DAY) ***
# # JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ***
61 .15 .15 .15 .15 .90 5.2 6.0 6.0 6.0 6.0 .15 .15
END MON-PHOSUPT
*** DEFAULT PLANT UPTAKE OF PHOSPHORUS FROM GROUNDWATER ZONE TO ZERO
PHOS-FSTGEN
TEMPERATURE CORRECTION PARAMETERS FOR PHOSPHORUS REACTIONS ***
# # THPLP THKDSP THKADP THKIMP THKMP ***
61 1.07 1.07 1.05
END PHOS-FSTGEN
PHOS-FSTPM
PHOSPHORUS FIRST-ORDER RATES FOR SURFACE LAYER (/DAY) ***
# # KDSP KADP KIMP KMP ***
61 10.00 .001
136
-------
END PHOS-FSTPM
PHOS-FSTPM
PHOSPHORUS FIRST-ORDER RATES FOR UPPER LAYER (/DAY)
# # KDSP KADP KIMP KMP
61 3.0 .00005
END PHOS-FSTPM
***
***
PHOS-FSTPM
PHOSPHORUS FIRST-ORDER RATES FOR LOWER LAYER (/DAY)
# # KDSP KADP KIMP KMP
61 .100 .00007
END PHOS-FSTPM
***
***
PHOS-FSTPM
PHOSPHORUS FIRST-ORDER RATES FOR GROUNDWATER LAYER (/DAY)
# # KDSP KADP KIMP KMP
61 0. 0.00
END PHOS-FSTPM
***
***
PHOS-CMAX
MAXIMUM SOLUBILITY OF PHOSPHATE ***
# # CMAX ***
(PPM) ***
61 50.0
END PHOS-CMAX
PHOS-SVALPM
# #
61
SURFACE
XFIX K1
(PPM)
20. 5.
N1***
***
1.50
END PHOS-SVALPM
PHOS-SVALPM UPPER
XFIX K1
# # (PPM)
61 15. 5.
END PHOS-SVALPM
N1***
***
1.50
PHOS-SVALPM
XFIX
# # (PPM)
61 10.
END PHOS-SVALPM
LOWER
K1
5.
N1***
***
1.50
PHOS-SVALPM
XFIX
# # (PPM)
61 15.
END PHOS-SVALPM
GROUNDWATER
K1
7.
N1***
***
1.50
PHOS-STOR1
INITIAL PHOSPHORUS STORAGE IN SURFACE LAYER LB/AC ***
# # ORGP P4AD P4SU PLTP ***
61 50. 2.00 0.00 0.
END PHOS-STOR1
PHOS-STOR1
INITIAL PHOSPHORUS STORAGE IN UPPER LAYER LB/AC ***
# # ORGP P4AD P4SU PLTP . ***
61 100. 28.0 1.00 0.
END PHOS-STOR1
PHOS-STOR1
INITIAL PHOSPHORUS STORAGE IN LOWER LAYER LB/AC
# # ORGP P4AD P4SU PLTP
61 60. 140. 1.5 0.
END PHOS-STOR1
***
***
137
-------
PHOS-STOR1
INITIAL PHOSPHORUS STORAGE IN GROUNDWATER LAYER LB/AC ***
# # ORGP P4AD P4SU PLTP ***
61 30. 210. 01.0 0.
END PHOS-STOR1
*** INTERFLOW STORAGES DEFAULTED TO ZERO
END PERLND
RCHRES
ACTIVITY
RCHRES Active Sections (1=Active; 0=Inactive) ***
# - # HYFG ADFG CNFG HTFG SDFG GQFG OXFG NUFG PKFG PHFG ***
60 11011 111
END ACTIVITY
PRINT-INFO
RCHRES Print-flags
# - # HYDR ADCA CONS HEAT
60 55 5
END PRINT-INFO
SED
5
GQL OXRX NUTR PLNK PHCB PIVL
555
PYR ***
12
GEN-INFO
RCHRES< Name-
# - #
60 REACH 60
END GEN-INFO
>Nexit Unit Systems Printer ***
User t-series Engl Metr LKFG ***
in out ***
1 1 1 1 90 0 0
HYDR-PARH1
RCHRES Flags for HYDR section
# - # VC A1 A2 A3 ODFVFG for each
FG FG FG FG
60 1
END HYDR-PARM1
1 1
possible
1 2 3
4
exit
4 5
ODGTFG for each *** FUNCT for each
possible exit *** possible exit
12345*** 12345
HYDR-PARM2
RCHRES
# - # FTABNO
60 60
END HYDR-PARM2
LEN
7.0
DELTH
350.0
STCOR
KS
.5
***
DB50 ***
HYDR-INIT
RCHRES Initial conditions for HYDR section
# - # VOL Initial value of COLIND
(ac-ft) for each possible exit
EX1 EX2 EX3 EX4 EX5
60 200.00
END HYDR-INIT
***
***
Initial value of OUTDGT
for each possible exit
EX1 EX2 EX3 EX4 EX5
0.0
HEAT-PARM
RCHRES ELEV
# - #
60 1000.
END HEAT-PARM
ELDAT CFSAEX KATRAD KCOND
ELV OF GAGE 660 FT
340. .10 10.25 6.75
KEVAP ***
***
1.10
HEAT-INIT
RCHRES
# - #
60
END HEAT-INIT
TW
33.
AIRTMP ***
***
33.
SANDFG
RCHRES ***
# - # SDFG ***
60 3
END SANDFG
138
-------
SED-GENPARM
RCHRES BEDWID
# - # (ft)'
60 30.
END SED-GENPARM
SAND-PM
RCHRES D
# - # (in)
60 .005
END SAND-PM
SILT-CLAY-PM
RCHRES D
# - # (in)
60 0.00040
END SILT-CLAY-PM
SILT-CLAY-PM
RCHRES D
# - # (in)
60 0.00010
BEDWRN
(ft)
3.
W
(in/s)
0.25
U
(in/s)
0.0035
POR
(-)
0.4
RHO
(g/cm3)
2.5
SILT
RHO
(g/cm3)
2.4
***
***
KSAND EXPSND ***
***
.002 3.0
PARAMETERS
TAUCD TAUCS
0.9 1.10
M ***
***
.005
CLAY PARAMETERS
U
(in/s)
0.00015
RHO
(g/cm3)
2.4
TAUCD TAUCS
0.9 1.10
M ***
***
.01
END SILT-CLAY-PM
SSED-INIT
RCHRES Suspended sed cones (mg/t) ***
# - # Sand Silt Clay ***
60 0. 5. . 5.
END SSED-INIT
BED-INIT
RCHRES
# - #
60
END BED-INIT
BEDDEP Initial bed composition
(ft)
2.
Sand
.52
Silt
.33
Clay ***
.15
BENTH-FLAG
RCHRES BENF ***
# - # ***
60 0
END BENTH-FLAG
OX-FLAGS
RCHRES REAM ***
# - # ***
60 2
END OX-FLAGS
OX-GENPARM
RCHRES KBOD20
# - # /hr
60 .001
END OX-GENPARM
OX-REAPARM ***
***** REAK= .484*1.5
RCHRES TCGINV
# - #
60 1.024
END OX-REAPARM ***
OX-BENPARM
RCHRES BENOD
# # /hr
60 100.
TCBOD
1.047
(SEE HSPQ
REAK
/hr
.25
TCBEN
1.074
KODSET
.010
pg.195;
EXPRED
-1.673
EXPOD
1.22
SUPSAT ***
***
1.25
HSPF pg. 509) *****
EXPREV ***
***
.969 ***
BRBOD(A) BRBOD(2)
mg/m2.hr mg/m2.hr
.001 .001
EXPERL ***
***
2.82
END OX-BENPARM
OX-INIT
RCHRES
DOX
BOD
SATDO
139
-------
# #
60
END OX-INIT
mg/l
14.5
mg/l
1.3
mg/l ***
14.5
NUT- FLAGS
RCHRES TAH N02 P04 AMV DEN ADNH ADPO PHFG ***
# - # ***
60 1010111
END NUT- FLAGS
NUT-AD-FLAGS
Atmospheric Deposition Flags ***
N03 NH3 P04 ***
x -
60 -1 0
END NUT-AD-FLAGS
-10-10
CONV-VAL1
RCHRES CVBO
# - # mg/mg
60 1.63
END CONV-VAL1
CVBPC CVBPN
mols/mol moIs/moI
106. 16.
BPCNTC ***
***
49.
NUT-NITDENIT
RCHRES KTAM20 KN0220 TCNIT KN0320 TCDEN DENOXT ***
# - # /hr /hr /hr mg/l ***
60 .006 .002 1.045 .002 1.024 10.0
END NUT-NITDENIT
NUT-BEDCONC
RCHRES Bed concentrations of NH4 & P04 (mg/kg)
# - # NH4-sand NH4-silt NH4-clay P04-sand P04-silt
60 20. 50. 50. 50. 150.
END NUT-BEDCONC
P04-clay ***
150.
NUT-ADSPARM
RCHRES Partition coefficients for NH4 AND P04 (ml/g) ***
# - # NH4-sand NH4-silt NH4-clay P04-sand P04-silt P04-clay ***
60 10. 100. 100. 100. 1000. 1000.
END NUT-ADSPARM
NUT-DINIT
RCHRES N03 TAM N02 P04
# - # mg/l mg/l mg/l mg/l
60 1.0 .050 0. .01
END NUT-DINIT
PH ***
***
0.
NUT-ADSINIT
RCHRES Initial suspended NH4 and P04 concentrations (mg/kg) ***
#- # NH4-sand NH4-silt NH4-clay P04-sand P04-silt P04-clay ***
60 0. 0. 0. 0. 0. 0.
END NUT-ADSINIT
PLNK- FLAGS
RCHRES PHYF ZOOF BALF SDLT AMRF DECF NSFG ZFOO ***
# - # ***
60 00000112
END PLNK- FLAGS
PLNK-AD- FLAGS
Atmospheric Deposition Flags ***
ORN ORP ORC ***
x - x ***
60 -10-10 00
END PLNK-AD-FLAGS
BENAL-PARM
RCHRES
# - #
MBAL
mg/m2
CFBALR CFBALG
***
***
140
-------
60 150.
END BENAL-PARM
.50
1.0
PLNK-PARM1
RCHRES RATCLP
# - #
60 .68
END PLNK-PARM1
PLNK-PARM2
RCHRES *** CMMLT
# - # ***ly/min
60 .01
END PLNK-PARM2
PLNK-PARM3
RCHRES ALR20
# - # /hr
60 .003
END PLNK-PARH3
PHYTO-PARM
RCHRES SEED
# - # mg/l
60 .5
END PHYTO-PARM
PLNK-INIT
RCHRES PHYTO
# - # tng/l
60 5.0
END PLNK-INIT
END RCHRES
FTABLES
FTABLE 60
ROWS COLS ***
17 4
DEPTH AREA
(FT) (ACRES)
0. 0.0
1.2 27.49
1.3 27.66
1.7 28.34
2.1 29.02
2.5 29.70
3.0 30.55
3.6 31.56
4.1 32.41
5.2 36.20
6.2 47.52
7.0 56.57
7.8 65.62
8.3 71.27
9.0 79.19
10.0 90.51
100.0 905.10
END FTABLE 60
END FTABLES
NONREF
.5
CMMN
mg/l
.015
ALDH
/hr
.02
HXSTAY
mg/l
1.
ZOO
org/l
.03
VOLUME
(AC-FT)
0.0
31.77
34.52
45.72
57.20
68.94
84.00
102.63
118.63
155.50
197.36
238.99
287.86
322.08
374.75
459.60
4596.00
LITSED
0.0
CMMNP
mg/l
.001
ALDL
/hr
.001
OREF
6000.
BENAL
mg/m2
150.
DISCH
(CFS)
0.0
0.0
.27
13.2
68.5
172.0
372.0
705.0
1060.0
2002.0
3036.0
3992.0
5098.0
5880.0
6800.0
7800.0
78000.0
ALNPR EXTB MALGR ***
/ft /hr ***
.35 .30 .075
CMMP TALGRH TALGRL TALGRM
mg/l deg F deg F deg F
.001 95. -10.0 86.
OXALD NALDH PALDH ***
/hr mg/l mg/l ***
.03 .01 .002
CLALDH PHYSET REFSET ***
ug/l ***
30. .020 .065
ORN ORP ORC ***
mg/l mg/l mg/l ***
0. 0. 0.
FLO-THRU ***
(MIN) ***
0.
0.
0.
332.
210.
162.
134.
117.
104.
87.
76.
68.
60.
60.
60.
60.
60.
EXT SOURCES
<-Volume-> SsysSgap<--Mult-->Tran <-Target vols> <-Grp> <-Member->***
# # tern strg<-factor->strg
1.18 SAME PERLND
0.82 DIV PERLND
SAME PERLND
SAME PERLND
SAME PERLND
SAME PERLND 61 EXTNL SOLRAD
WDM
WDM
WDM
WDM
WDM
WDM
309 HPRC
20 EVAP
316 ATMP
21 DEWP
24 WNDH
26 RADH
10 ENGLZERO
ENGLZERO
ENGLZERO
ENGLZERO
ENGLZERO
ENGLZERO
#
61
61
61
61
61
#
EXTNL
EXTNL
EXTNL
EXTNL
EXTNL
PREC
PETINP
GATMP
DTMPG
UINMOV
# #***
141
-------
WDM 309
WDM 20
WDM 21
WDM 22
WDM 24
WDM 26
WDM 316
HPRC 10 ENGLZERO 1.18 SAME
EVAP ENGLZERO 0.82 DIV
DEWP ENGLZERO SAME
CLDC ENGLZERO SAME
WNDH ENGLZERO SAME
RADH ENGLZERO SAME
ATMP ENGLZERO SAME
RCHRES
RCHRES
RCHRES
RCHRES
RCHRES
RCHRES
RCHRES
60
60
60
60
60
60
60
EXTNL
EXTNL
EXTNL
EXTNL
EXTNL
EXTNL
EXTNL
PREC
POTEV
DEWTMP
CLOUD
WIND
SOLRAD
GATMP
**** ATM DEPOSITION
WDM 531
WDM 532
WDM 533
WDM 535
WDM 534
WDM 536
WDM 531
WDM 532
WDM 533
WDM 535
WDM 534
WDM 536
NH4X
N03X
N03X
ORGN
P04X
ORGP
NH4X
N03X
N03X
ORGN
P04X
ORGP
ENGL
ENGL
ENGL
ENGL
ENGL
ENGL
ENGL
ENGL
ENGL
ENGL
ENGL
ENGL
DIV
DIV
DIV
DIV
DIV
DIV
DIV
DIV
DIV
DIV
DIV
DIV
PERLND
PERLND
PERLND
PERLND
PERLND
PERLND
RCHRES
RCHRES
RCHRES
RCHRES
RCHRES
RCHRES
61
61
61
61
61
61
60
60
60
60
60
60
EXTNL
EXTNL
EXTNL
EXTNL
EXTNL
EXTNL
EXTNL
EXTNL
EXTNL
EXTNL
EXTNL
EXTNL
NIADFX
NIADFX
NIADFX
NIADFX
PHADFX
PHADFX
NUADFX
NUADFX
NUADFX
PLADFX
NUADFX
PLADFX
2
1
1
3
1
2
2
1
1
1
3
2
1
1
1
1
1 ***
1 ***
1
1
1
1
1
1
END EXT SOURCES
SCHEMATIC
<-Source->
#
PERLND 61
PERLND 61
<--Area-->
<-factor->
29568.
29568.
<-Target-> ***
RCHRES
COPY
#
60
600
# ***
1
91
END SCHEMATIC
MASS-LINK
MASS-LINK
PERLND
PERLND
PERLND
PERLND
PERLND
PERLND
PERLND
PERLND
PERLND
PERLND
PERLND
PERLND
<-Grp>
PWATER
SEDMNT
SEDMNT
SEDMNT
PWTGAS
PWTGAS
NITR
NITR
NITR
NITR
NITR
NITR
1
<-Member-x--Mult-->
PERO
SOSED
SOSED
SOSED
POHT
PODOXM
PON03
TSAMS
TSAMS
SSAMS
SEDN
SEDN
*** REFRACTORY ORGANIC N
PERLND
PERLND
PERLND
PERLND
*** LABILE
NITR
NITR
NITR
NITR
ORGANIC
SEDN
TSSRN
TSSRN
SSSRN
N TO
*** CVBO/CVBN = 18.953;
PERLND
PERLND
PERLND
PERLND
NITR
NITR
NITR
NITR
END MASS- LINK
MASS- LINK
<-Volume->
<-Grp>
SEDN
TSSLN
TSSLN
SSSLN
1
91
#
#<-factor->
0.0833333
1
1
1
1
5
3
2
2
0.04
0.69
0.27
0.70
0.30
RCHRES
RCHRES
RCHRES
RCHRES
RCHRES
RCHRES
RCHRES
RCHRES
RCHRES
RCHRES
RCHRES
RCHRES
<-Grp>
INFLOW
INFLOW
INFLOW
INFLOW
INFLOW
INFLOW
INFLOW
INFLOW
INFLOW
INFLOW
INFLOW
INFLOW
<-Member-> ***
I VOL
ISED
ISED
ISED
I HEAT
OXIF
NUIF1
NUIF1
NUIF1
NUIF1
NUIF2
NUIF2
#
1
2
3
1
1
2
2
2
2
3
# ***
1
1
TO RCHRES ***
3
1
5
3
RCHRES
RCHRES
RCHRES
RCHRES
INFLOW
INFLOW
INFLOW
INFLOW
PKIF
PKIF
PKIF
PKIF
3
3
3
3
RCHRES
CVBO =1.63
1
1
5
3
18.953
18.953
18.953
18.953
mgO/mg
<-Member-><--Mult-->Tran
X
x<-factor
->stra
Biomass; CVBN
RCHRES
RCHRES
RCHRES
RCHRES
<-Target vols>
= .086 mgN/mg
INFLOW
INFLOW
INFLOW
INFLOW
<-Grp>
OXIF
OXIF
OXIF
OXIF
Biomass ***
2
2
2
2
<-Member
X
_> ***
X ***
PERLND PWATER SURO COPY INPUT MEAN 1
PWATER IFWO COPY INPUT MEAN 2
PERLND
PERLND
PWATER AGWO
COPY
INPUT MEAN
142
-------
PERLND
PERLND
PERLND
PERLND
PWATER PET
PWATER TAET
PWATER UZS
PWATER LZS
COPY
COPY
COPY
COPY
INPUT MEAN 4
INPUT MEAN 5
INPUT MEAN 6
INPUT MEAN 7
END MASS-LINK 91
END MASS-LINK
NETWORK
<-Volume-> <-Grp> <-Member-x--Mult-->Tran <-Target vots> <-Grp> <-Member-> ***
# # #<-factor->strg # # # # ***
PERLND
PERLND
GENER
PERLND
PERLND
GENER
PERLND
PERLND
GENER
61
61
1
61
61
2
61
61
3
NITR
PWATER
OUTPUT
NITR
PWATER
OUTPUT
NITR
PWATER
OUTPUT
**** PARTICULATE
RCHRES
RCHRES
GENER
RCHRES
60
60
4
60
**** TOTAL
RCHRES
RCHRES
GENER
RCHRES
60
60
4
60
*** TOTAL
RCHRES
RCHRES
60
60
*** TOTAL
RCHRES
RCHRES
RCHRES
RCHRES
60
60
60
60
*** BELOW
PERLND
PERLND
PERLND
PERLND
61
61
61
61
NUTRX
HYDR
OUTPUT
PLANK
N
NUTRX
NUTRX
OUTPUT
PLANK
PON03
PERO
TIMSER
PONH4
PERO
TIMSER
POORN
PERO
TIMSER
N (ADS
RSNH4
VOL
TIMSER
PKST3
DNUST
DNUST
TIMSER
PKST3
NH3 (DISS NH3
NUTRX
NUTRX
NUCF1
NUCF2
NH3 +
4
4
1
2
4
+ ADS
2
4 1
0.0833
0.368
0.0833
0.368
0.0833
0.368
ORG N)
0.368
0.368
SAME
SAME
SAME
AVER
AVER
SAME
AVER
AVER
AVER
SAME
AVER
NH3) LOADING
N LOADING - N03 + NH3 + ORN
NUTRX
NUTRX
NUTRX
PLANK
GROUND
NITR
NITR
NITR
NITR
NUCF1
NUCF1
NUCF2
PKCF1
1
2
4 1
3
***
GENER
GENER
COPY
GENER
GENER
COPY
GENER
GENER
COPY
GENER
GENER
COPY
COPY
COPY
COPY
COPY
COPY
***
COPY
COPY
COPY
COPY
COPY
COPY
1
1
1
2
2
1
3
3
1
4
4
1
1
1
1
1
1
1
1
1
1
1
1
INPUT
INPUT
INPUT
INPUT
INPUT
INPUT
INPUT
INPUT
INPUT
INPUT
INPUT
INPUT
INPUT
INPUT
INPUT
INPUT
INPUT
INPUT
INPUT
INPUT
INPUT
INPUT
INPUT
ONE
TWO
MEAN
ONE
TWO
MEAN
ONE
TWO
MEAN
ONE
TWO
MEAN
MEAN
MEAN
MEAN
MEAN
MEAN
MEAN
MEAN
MEAN
MEAN
MEAN
MEAN
1
2
3
4
4
5
5
5
5
6 ***
6 ***
7 ***
7 ***
7 ***
7 ***
PLANT N ***
SN
UN
LN
AN
5
5
5
5
COPY
COPY
COPY
COPY
1
1
1
1
INPUT
INPUT
INPUT
INPUT
POINT
POINT
POINT
POINT
1
1
1
1
END NETWORK
GENER
OPCODE
#thru# code ***
1 4 19
61 24
END OPCODE
PARM
#thru#
61
END PARM
END GENER
EXT TARGETS
constant ***
0
143
-------
<-Voluroe-> <-Grp> <-Hember-x--Mult-->Tran <-Volume-> Tsys Tgap Amd ***
# # #<-factor->strg # # tern strg strg***
RCHRES 60 HYDR RO
PERLND 61 SNOW PDEPTH
RCHRES 60 SEDTRN SSED 4
RCHRES 60 HYDR TAU
***Expert System Data Sets to WDM***
COPY 600 OUTPUT MEAN 1 .00003382
COPY 600 OUTPUT MEAN 2 .00003382
COPY 600 OUTPUT MEAN 3 .00003382
COPY 600 OUTPUT MEAN 4 .00003382
COPY 600 OUTPUT MEAN 5 .00003382
COPY 600 OUTPUT MEAN 6 .00003382
COPY 600 OUTPUT MEAN 7 .00003382
RCHRES 60 ROFLOW ROVOL .00040584
COPY 1 OUTPUT MEAN 1
COPY 1 OUTPUT MEAN 2
COPY 1 OUTPUT MEAN 3
PERLND 61 NITR AGPLTN
COPY 1 OUTPUT POINT 1
PERLND 61 NITR LITTRN
PERLND 61 NITR TOTNIT
PERLND 61 NITR TN 5
PERLND 61 PWATER PERO
PERLND 61 NITR TN 1
PERLND 61 NITR TN 7
GENER 61 OUTPUT TIMSER
PERLND 61 NITR SN 3
PERLND 61 NITR UN 3
PERLND 61 NITR LN 3
PERLND 61 NITR AN 3
PERLND 61 NITR TN 3
PERLND 61 NITR SN 4
PERLND 61 NITR UN 4
PERLND 61 NITR LN 4
PERLND 61 NITR AN 4
PERLND 61 NITR TN 4
RCHRES 60 NUTRX DNUST 1
RCHRES 60 NUTRX DNUST 2
COPY 1 OUTPUT MEAN 4
COPY 1 OUTPUT MEAN 5
RCHRES 60 PLANK PHYCLA
RCHRES 60 PLANK PKST3 6
RCHRES 60 OXRX DOX
RCHRES 60 OXRX BOD
RCHRES 60 HTRCH TW
PERLND 61 PSTEMP SLTMP
PERLND 61 PSTEMP ULTMP
PERLND 61 PSTEMP LGTMP
AVER WDM
AVER WDM
AVER WDM
AVER WDM
WDM
WDM
WDM
WDM
WDM
WDM
WDM
WDM
AVER WDM
AVER WDM
AVER WDM
AVER WDM
AVER WDM .
AVER WDM
AVER WDM
AVER WDM
AVER WDM
AVER WDM
AVER WDM
SUM WDM
AVER WDM
AVER WDM
AVER WDM
AVER WDM
AVER WDM
AVER WDM
AVER WDM
AVER WDM
AVER WDM
AVER WDM
AVER WDM
AVER WDM
AVER WDM
AVER WDM
AVER WDM
AVER WDM
AVER WDM
AVER WDM
AVER WDM
AVER WDM
AVER WDM
AVER WDM
1701 FLOW
1716 SNOW
1702 SEDM
1717 TAUX
401 SURO
402 IFWO
403 AGWO
404 PETX
405 SAET
406 UZST
407 LZST
408 QDEP
2004 N03X
2005 NH3X
2006 ORGN
2007 NITR
2022 NITR
2008 NITR
2009 NITR
2010 NITR
2011 PERO
2023 NITR
2024 NITR
2025 NITR
2012 NITR
2013 NITR
2014 NITR
2015 NITR
2016 NITR
2017 NITR
2018 NITR
2019 NITR
2020 NITR
2021 NITR
1706 N03X
1705 NH4X
1707 ORGN
1708 TOTN
1713 CHLA
1712 TOCX
1704 DOXX
1714 BODX
1703 WTMP
2001 STMP
2002 STMP
2003 STMP
ENGL AGGR REPL
ENGL AGGR REPL
ENGL AGGR REPL
ENGL AGGR REPL
ENGL AGGR REPL
ENGL AGGR REPL
ENGL AGGR REPL
ENGL AGGR REPL
ENGL AGGR REPL
ENGL AGGR REPL
ENGL AGGR REPL
ENGL AGGR REPL
ENGL AGGR REPL
ENGL AGGR REPL
ENGL AGGR REPL
ENGL AGGR REPL
ENGL AGGR REPL
ENGL AGGR REPL
ENGL AGGR REPL
ENGL AGGR REPL
ENGL AGGR REPL
ENGL AGGR REPL
ENGL AGGR REPL
ENGL AGGR REPL
ENGL AGGR REPL
ENGL AGGR REPL
ENGL AGGR REPL
ENGL AGGR REPL
ENGL AGGR REPL
ENGL AGGR REPL
ENGL AGGR REPL
ENGL AGGR REPL
ENGL AGGR REPL
ENGL AGGR REPL
ENGL AGGR REPL
ENGL AGGR REPL
ENGL AGGR REPL
ENGL AGGR REPL
ENGL AGGR REPL***
ENGL AGGR REPL***
ENGL AGGR REPL
ENGL AGGR REPL
METR AGGR REPL
ENGL AGGR REPL***
ENGL AGGR REPL***
ENGL AGGR REPL***
END EXT TARGETS
COPY
TIMESERIES
#thru# NPT NMN
1 1 5
600 7
END TIMESERIES
END COPY
END RUN
144
------- |