United States
Environmental Protection
Agency
Office of Water
(4305)
EPA-823-R-00-006
September 2000
»EPA AQUATOX FOR WINDOWS
A MODULAR FATE AND EFFECTS
MODEL FOR AQUATIC ECOSYSTEMS
RELEASE 1
VOLUME 1: USER'S MANUAL
-------
-------
AQUATOX FOR WINDOWS
A MODULAR FATE AND EFFECTS MODEL
FOR AQUATIC ECOSYSTEMS
RELEASE 1
VOLUME 1: USER'S MANUAL
SEPTEMBER 2000
U.S. ENVIRONMENTAL PROTECTION AGENCY
OFFICE OF WATER
OFFICE OF SCIENCE AND TECHNOLOGY
WASHINGTON DC 20460
-------
DISCLAIMER
This document has been approved for publication by the Office of Science and Technology, Office
of Water, U.S. Environmental Protection Agency. Mention of trade names, commercial products
or organizations does not imply endorsement or recommendation for use.
This document describes a new aquatic ecosystem simulation model. It is not intended to serve as
guidance or regulation, nor is the use of this model in any way required. This document cannot
impose legally binding requirements on EPA, States, Tribes, or the regulated community.
ACKNOWLEDGMENTS
This model has been developed and documented by Dr. Richard A. Park of Eco Modeling;
most of the programming has been by Jonathan S. Clough under subcontract to Eco Modeling. It
was funded with Federal funds from the U.S. Environmental Protection Agency, Office of Science
and Technology under contract number 68-C4-0051 to The Cadmus Group, Inc. Work assignment
managers for The Cadmus Group have been Paul Jacobson, Jonathan Butcher, and William Warren-
Hicks; their help in expediting the contractual arrangements and in reviewing the scientific
approaches is appreciated. Revision of the documentation has been performed under subcontract
to AQUA TERRA Consultants, Anthony Donigian, Work Assignment Manager, under EPA
Contract 68-C-98-010. v
Additional Federal funding for program development has come from the U. S. Environmental
Protection Agency, Office of Pollution Prevention and Toxics, through Purchase Orders 7W-0227-
NASA and 7W-4330-NALX to Eco Modeling.
The assistance, advice, and comments of the EPA work assignment manager, Marjorie
Coombs Wellman of the Exposure Assessment Branch, Office of Science and Technology has been
of great value in developing this model and preparing this report. Further technical and financial
support from David A. Mauriello and Rufus Morison of the Office of Pollution Prevention and
Toxics is gratefully acknowledged.
In an earlier version of the model developed at Abt Associates, Brad Firlie facilitated the
programming; Rodolfo Camacho developed and programmed the inorganic sediment constructs; and
review was provided by Lisa Akeson, Elizabeth Fechner-Levy, and Keith Sappington.
n
-------
TABLE OF CONTENTS
1. QUICK START 1-1
1.1 System Requirements 1-1
1.2 Installation 1-1
1.3 Starting 1-2
1.4 Loading a Study 1-2
1.5 Loading a Library 1-5
1.6 Running and Saving a Simulation 1-8
1.7 Running Batch Mode 1-8
2. MODEL COMPONENTS 2-1
2.1 State Variables 2-1
Selection 2-1
Initial Conditions 2-2
Parameters 2-4
Loadings 2-8
2.2 Sites 2-11
Selection 2-11
Site Characteristics 2-13
2.3 Driving Variables .. 2 - 14
2.4 Setup 2-16
2.5 Output 2-19
Tables 2-19
Graph 2-22
Files ..-../ 2-26
3. APPLICATIONS ,. 3 - 1
3.1 Nutrient Enrichment 3-1
3.2 Contamination by Organic Toxicants 3-9
3.3 Multiple Stressors Due To Agricultural Runoff 3 - 16
Controlling Nutrients and Sediments 3-16
Controlling Pesticides 3-27
Controlling All Pollutants 3-32
4. UNCERTAINTY ANALYSIS 4-1
5. DATA CONSIDERATIONS 5-1
5.1 Toxicant . ..: 5 - 1
5.2 Nutrients and Remineralization 5-1
5.3 Plants 5-2
5.4Animals 5-2
5.5 Inorganic Sediments .....5-2
6. QUALITY ASSURANCE ,6-1
in
-------
PREFACE
The Clean Water Act— formally the Federal Water Pollution Control Act Amendments of
1972 (Public Law 92-50), and subsequent amendments in 1977,1979,1980,1981,1983, and 1987—
calls for the identification, control, and prevention of pollution of the nation's waters. In the
National Water Quality Inventory: 1996 Report to Congress, 36 percent of assessed river lengths
and 39 percent of assessed lake areas were impaired for one or more of their designated uses (US
EPA 1998). The most commonly reported causes of impairment in rivers and streams were siltation,
nutrients, bacteria, oxygen-depleting substances, and pesticides; in lakes and reservoirs the causes
also included metals and noxious aquatic plants. The most commonly reported sources of
impairment were agriculture, nonpoint sources, municipal point sources, atmospheric deposition,
hydro logic modification, habitat alteration and resource extraction. There were 2196 fish
consumption advisories, which may include outright bans, in 47 States, the District of Columbia and
American Samoa. Seventy-six percent of the advisories were due to mercury, with the rest due to
PCBs, chlordane, dioxin, and DDT (US EPA 1998). States are not required to report fish kills for
the National Inventory; however, available information for 1992 indicated 1620 incidents in 43
States, of which 930 were attributed to pollution, particularly oxygen-depleting substances,
pesticides, manure, oil and gas, chlorine, and ammonia.
New approaches and tools, including appropriate technical guidance documents, are needed
to facilitate ecosystem analyses of watersheds as required by the Clean Water Act. In particular,
there is a pressing need for refinement and release of an ecological risk methodology that addresses
the direct, indirect, and synergistic effects of nutrients, metals, toxic organic chemicals, and non-
chemical stressors on aquatic ecosystems, including streams, rivers, lakes, and estuaries.
r-
The ecosystem model AQUATOX is one of the few general ecological risk models that
represents the combined environmental fate and effects of toxic chemicals. The model also
represents conventional pollutants, such as nutrients and sediments, and considers several trophic
levels, including attached and planktonic algae, submerged aquatic vegetation, several types of
invertebrates, and several types offish. It has been implemented for streams, small rivers, ponds,
lakes, and reservoirs.
The AQUATOX model is described in these documents. Volume 1: User's Manual
describes the usage of the model. Because the model is menu-driven and runs under Microsoft
Windows on microcomputers, it is user-friendly and little guidance is required. Volume 2:
Technical Documentation provides detailed documentation of the concepts and constructs of the
model so that its suitability for given applications can be determined. Volume 3: Model Validation
Reports presents three model validation studies performed for different environmental stressors and
in different waterbody types.
IV
-------
AQUATOX USER'S MANUAL
CHAPTER 1
1. QUICK START
1.1 System Requirements
Minimum Requirements
PC Compatible, Intel 486DX 66 MHz
Microsoft Windows 95, 98, or NT
16MB RAM
• 30 MB free disk space
Recommended
Pentium PC, 300 MHz or higher
64 MB RAM
• 75 MB free disk space
1.2 Installation
To install AQUATOX, run AQTXSetup.exe, the files will unzip, and InstallShield will lead
you through the straightforward installation.
WinZip Self-Extractor [AQTXSetup.exe]
.
Welcome to
AOUATOX setup
1-1
-------
AQUATOX USER'S MANUAL
CHAPTER 1
1.3 Starting
Double-click on the AQUATOX icon in Windows to open the program.
Then a "splash" window will open briefly, indicating that the model is still subject to modification
and that, while the model is in the public domain, there are parts of the model interface that are
proprietary.
AQUATOX
Version 1.69
Richard A. Park and Jonathan S. Cfough_
Eco Modeling 1999
Developed with EPA funding under contracts
| 3 68-04-0051, 68-C-98-010, 7W-4330-^tALXy
RESTRICTED RIGHTS NOTICE: Use, duplication, oraisdtosurefe
sufiiect to restrictions as set forth in subdivision (g)(3)(1 J'of the.
Rights in Data-General, Alternate lit dans?! 52 227-14 of the
Federal Acquisition Regulation ",, >*,
' /
This software and associated files are distributed "a& is"
without any warranties of performance or fitness for any
particular purpose. Ho warranties are expressed or
— - implied, j.
~ _ Bi-'xf* 4
1.4 Loading a Study
The study is the basic unit hi AQUATOX; it contains site data, loadings, and parameter
values used in a simulation; and it may contain results from a prior simulation. Usually we model
one study at a tune; however, there is a batch mode that is described later. Click on File in the menu
bar to get the pull-down file menu, and click on Open. You will then be given a choice of
AQUATOX study files to load. For this example we will choose Esfenpond.aps.
1-2
-------
AQUATOX USER'S MANUAL
CHAPTER 1
•!nSpid^™«!tw»rWRi«j!4t»-«--" "
:
t-4* . ',%>><
AgricRes.aps
2] ChlorLow.aps
21 ChlorMed.aps
Coralvillc.aps
Zl DorParathion.aps
Zl EFPoplarCr.a
& Program Flies
& AQUATOX
UATOX Studies {".APS) &jS c:J
The main window will appear with the name of the study, the list of state variables used, and
buttons from which to choose various operations. The Study Name can be edited; it is separate from
the name of the file, which you loaded and which is displayed at the top of the screen. The study
name is used as a title in graphical output, so is best capitalized. The Status window tells when the
perturbed and control runs were made, and warns if they are incomplete or outdated. The Initial
Conditions button brings up a screen with all the state variable values at the beginning of a
simulation. The Chemical button brings up the parameter screen for the organic toxicant, if
modeled. Double clicking on Dissolved org. toxicant at the top of the list of state variables and
driving variables has the same effect. The Site button loads the site characteristic screen. Setup
allows the user to set the dates of the simulation, and to specify various options such as the control
setup, uncertainty analysis, and saving biologic rates. Notes provides a window for writing
comments on the study. Perturbed starts the simulation with changed conditions, such as with a
toxicant. Control starts a simulation without the stressor; the user can use Control Setup as
mentioned above to specify what is changed and what is held constant. Output presents the results
as a series of charts and graphs. The output can be exported as database files by clicking on Export
Results or Export Control. Help is not yet implemented, except the About window, which brings
up the splash window.
1-3
-------
AQUATOX USER'S MANUAL
CHAPTER 1
EAOUATOX- F« Windowr "ESFcnPondops"
0. U»«JP Studjf
•N "> < -W •"-**,
AQUATOX: Study Information
Study Hame: |ESFEHVAl.ERATl^PpNp
Model Run Status:
Puiluibod Run: No Run Recorded
Control Run; No Ctrl. Run Recorded
Data Operations; i Program Operations
[ J||| Initial Conds. I 1 )g'"'BSf!> Eerturbed
Chnmlcal
Site
Sfitup
Uotos
Conlrol
Output
"i Bf Export Results
Export Contiol
! ^state and Dftvlnfl Variables In Study
i w
Dbsolved org. toxicant: [EsfenVataratu]
Ammonia
Nitrate
Phosphate
Oxygen '
Labile sed. detritus
fUfrac. sett, detritus
Susp. and dissolved detritus
Buried labile detritus
Buried refrac. detritus ,
Diatoms: [Diatoms] , .,
aiuo-graans; [Blue^reens] "^N* "^
Greens: [Periphyton, Greonsj *• ^
Macrophytes: [Myriophytlumj
D8trItlvorouilnv8rtobrate:[ChlronomldI
Horblvorous invertebrate: [Daphnlal
Predatory Invertebrate; [Predatory Zooplank.)
Bottom fish: [Catfish) '
Small game fish: [iargDmauth Bass, YOY]
Large game fish: [Largcmouth Bass, Lg}
Water Volume • " ' M Sit - -^
pH
Light _ ""'
Tomporature
Wind Loading
To save a file, click on File then Save or Save As on the menu bar; you will also be given
an opportunity to save an altered file before exiting or loading another file. Study files range in size
from 25 KB to over 2 MB. If you wish to minimize the size of a study—for example, to transmit
to someone else—you can strip out the results by clicking on Study and choosing Clear Results
from the menu bar. The study files distributed with AQUATOX have been minimized in this way.
IgjAQUATOX-- For Windows: "ESrenPOND.aps"
Stu
P
Model up
•i^_ Control
-------
AQUATOX USER'S MANUAL
CHAPTER 1
1.5 Loading a Library
There is a basic dichotomy in working with AQUATOX. You have a choice of editing
database files in the general library or of opening a particular study. Studies are self-contained files
with all the information on a particular simulation, including initial conditions, loadings, parameter
values, first and last dates for the simulation, and simulation results. Parameter values can be edited,
but changes apply only to that study. The intent is to be able to archive a model application so that
all assumptions and results are saved for future reference. This is especially important for regulatory
applications that are subject to later review. (Of course, you also should archive the version of
AQUATOX that was used.)
Parameter and site records that will be used repeatedly should be saved in the appropriate
library. Each library is a database in Paradox format with records for each organism, chemical, or
site. Generally, editing of parameters should be done in the library mode to maintain consistency
among studies. In contrast, if a site record is only going to be used for a single study, it may be
desirable to create it within the study. Study records can be copied into the library; so the choice of
where to edit parameters is up to the user. It is the user's responsibility, though, to synchronize
parameter values among studies. This can be done by saving a record to a library and then loading
that record to each study.
To create or edit a record for general use, click on Library in the menu bar. You can then
click on the specific library from the pull-down menu.
^AQUATOX-- For Windows: "ESFenPond.aps1
'
Prs^^ipWf^^iifSi
_ "; •
In this example we will choose Chemical and Default in sequence. The first record is for atrazine.
We can click on the arrows in the upper left or can search for a particular name to move through the
database. Use the arrow to move to Esfenvalerate. When you leave a database you will be asked
whether you want to save it or lose any changes you might have made. The frequent requests for
confirmation may be irritating, but they are for your protection. Any time you leave a record you
may back out of a change by not saving it. There is no undo capability, so if you save a change, you
are stuck with it, except by re-editing the entire record. It is easy to print a record, and you are
1-5
-------
AQUATOX USER'S MANUAL
CHAPTER 1
encouraged to make a hard copy before you make extensive changes. Some variables are not used
at this time and are so indicated.
Chemical Properties and Fate Data: -
CAS Registry No |51630-5B-1 Chemical is a Base n»»V" •> e
Molecular Weight I 41951 References:
Dissociation Constant
Hcnty'tUw Constant
••'•'• " "" Ja | 5E7[mm Hg
OctinotWaltr , -—, - 1=——
Partition Coaftciant I &»LS°fl> jPlrariha
nT [ 41387X8^/t _ _ .
Ral» of Anaerobic i—
Microbial Degradation ' .
Rate of Aarobic
KaiB oi/wroDic i O^fi/d
Mistobial Degradation 1_ V
Uncatalyzsd i j, . p
hydrolysis constant L , >~—- I _
Add catalyzed
hydrolysis constant I ~ oil tool d f
Photolysis Rtta I
Osjra io Reach Equilibrium: 152.73
^s^j=^__',^" V^^^Jfe^ _ ,
il
l/d |SdiImmol at nt."B3
You can see the lower part of the screen, which gives toxicity data for the chemical, by
clicking on the scroll bar at the right or by clicking on the Toxicity Data button at the top right.
Toxicity can be estimated for several organisms, given data for others indicated in bold type. For
example, change the LC50 for trout from 1.3177 to 1.4 (or any other value). You will then get a
window presenting you with other organisms for which the LC50 can be estimated. If any have zero
values, they will be checked automatically. The estimation procedures were developed with
pesticide databases (Mayer and Ellersieck, 1986, Suter et al., 1986), so they should be applied with
caution to industrial chemicals.
1-6
-------
AQUATOX USER'S MANUAL
CHAPTER I
AQUATOX- Edil Chemical
M±El!bF
JgiM^SsSgfa
•"* -•" Acute •" Eitm. fiats'
Rainbow Trout I 1,31<^ Lo.0fl03.tr $6t| - 0.11
References: ,_
•^ , •*•* V
Bluegill | JM4 jjiMKHg, ] afi'l'- O.os'j jltS.EPA'Bff, p.6» V 1 ~
Bass J 1.483111 aooos iJ~^ii"',r0IT Jfiegres^ion on Blueglll^.'J,,^.,' ^ '
'' 00.7,927 •[ 0.0006 Jp,, gsYj. VoAttesgreiisioitoj
„ ^ ^ s ^ \J "^ XX
^ j -,-,
N , ., V
-0221/> OJM)29 ^ %" j 0,047 |u.S,feP,ft.
Daghnla | oH!| MftS,^" gfi j 0.06.| "', 48-hr;
* ChTOfrornia |, 0.3283) | J0.0084*]
sttmefly3j"^aot |r"|;b06*ir
0.05 [Regression on Daphnia
__ . .
Osttacoj)> 7ttJ
!36 I 0 Jiff
^a02fl"Onillp M"')^ ' 0.05 "JU'.SJ £.P.ft., 4B4ir. < OJJ2 " ~ s * „
• < 011 - 0 j Mf\^05>?l
$> 0.2
Greens j o | 03804- A
Dia|dms^,] o"| [ 0,3804j | afT 53"
r7H,i 55:=
'.Blue-Greens 28000>vfl
Macrophytes | o'J»flJ)905;p gs^j a5z,j „ ,,,r, , „
', *, ' growth /eoiaiaeak reprotfuction " comment:
Minnow | qJEZ. (1014 of LC50 "
Daph'nia | 0.0031 ilO%ofLCSO
0.0015 IS%ofLC5B
Using the,d^ta you entered, AQUATOX can oatcuiate
sftb cateulatel Empty cells have been selectee!;'
tff ", '. - K " ' - ".< ,<«:
W'-'-A"'.-*'—^ '• ' ^-y ^, .,4. ,- -
No Regiessioni
1-7
-------
AQUATOX USER'S MANUAL
CHAPTER 1
1.6 Running and Saving a Simulation
You can run both Perturbed and Control simulations to see the impacts of various stressors.
The results can be exported in dBase, Paradox, or text (Prn) formats. When you click on Export you
will be given the Study subdirectory as the default for saving the results; you may wish to choose
the Output or some other directory.
Export Results As:
i;. Savein: €3 Studies
•^Filename: j
i! Save as type:
save
DBase Format ».dbN
1.7 Running Batch Mode
There are applications where it is desirable to run a series of studies automatically. This can
be done by creating a Batch subdirectory under the Study directory and placing studies with
appropriately chosen options in it. The subdirectory should also contain a text file labeled
"batch.txt" that lists the names of the studies to be run, one to a line. On the menu bar you should
click on Run Batch on the pull-down File window. That will open a window that allows you to
Run in Batch Mode. You also can save the B AFs and organic-matter partition coefficients (KOMs)
to a comma-separated text file batchout.csv. (See Volume 2: Technical Documentation for
discussion of bioaccumulation of organic toxicants, BAFs and KOMs.) The Help button will give
you context-sensitive help.
1-
-------
AQUATOX USER'S MANUAL
CHAPTER 1
BAQUATOXVl.69
Run in Batch Mode
Output KUMs"fronrBateh Motfe,
1 T'/Help
I,,, , ., g,,,,,,,,,.
1-9
-------
AQUATOX USER'S MANUAL
CHAPTER 1
^^^H H elp with B atch M ode ' B|
ai>
kr
f
1
' t.. , i 4 l « * t', . - "- .- >S^^ ^^
f .,
'._
„
*
1 ,
i:
*
I.:.,
1 "
*
-jr -. j " <'<•„•" - ;, - :: „, ,, ,y.r.^
*£ i imf *•* t™1" ""8 « "fc^ 33 F * ?? * » •$* *^ <• ~ f, "i?.£_ * -^-^^ ^^,. , .A ,.? ,. t^z&ts Z?T .' /*'JSE*
Batch Mode Help: j
f
Batch Mode is designed to help the user run multiple files with one button press. This is I
especially useful for BAF analysis. |
To run a program in batch mode, you must have a subdirectory off of your Studies §
Subdirectory named "batch" I
In that "batch" subdirectory must be all studies you wish to run along with a file named ^
"batch.txt".
i
The batch.txt file must include each study name that you wish to run on a separate line. No f
blank lines may be included. ,
fc
The program will then execute each of the specified studies one by one and save them along |
with their results. I
To output the last BAF datapoint for each organism in each of the batch files, select the
Output button. This will open each study and write all of the BAF data from each study file into £
a CSV file named batchout.csv. ^
„ „_ . _ _ „„.„,_,,.„. r^v,,^^/^ ^^^.-,~!r«' (^ ff j,
&.
igi7
wu
is
k
g*<
f' yt
* /
w
ff>-
r
t*>
&• •&•
>,-„: "-V T^OK: J^
.. « _ .-.».-' - - ~ Jftf" ...5...!*-; -<- — -1 i — J
At this point you may experiment with the various buttons and screens. You cannot hurt
anything; just don't save the edited data or the study when you exit the screens and AQUATOX
unless you Save As a different name. On the other hand, if you are more comfortable following
directions, read on, doing the operations as you go.
1-10
-------
AQUA.TOX USER'S MANUAL
CHAPTER 2
2. MODEL COMPONENTS
2.1 State Variables
Selection—State variables are those ecosystem components that are being simulated. These include
organism and detrital compartments and their associated toxicants (which are not listed in the Study
Information window), nutrients, dissolved oxygen, and other variables traditionally considered
driving variables, such as water inflow, temperature, pH, light, and wind.
AQUATOX is very powerful because you can add or delete state variables. It is even
possible to remove all biotic components in order to model a tank or other sterile system. In general,
the fewer state variables, the better. In particular, unnecessary state variables slow down the
simulation and create additional requirements for verification. This is especially true for streams,
which tend to be more dynamic and therefore slower to simulate. Nevertheless, often it is desirable
to model a food web rather than a food chain, for example to examine the possibility of less tolerant
organisms being replaced by more tolerant organisms as environmental perturbations occur. The
choice of which state variables to model depends to a large extent on the purpose of the modeling
application.
,AQUATOX:~'Study Information
~* '~
]eSFi*pJ:Wp, PO*I0 \ ("
Model Run Status; H
Perturbed Rum *fo Run Recorded
Control Run: «o CM. Run Recorded ,i»,,
, Data Operations; '-^ Program 0|
; Chemical
Eorturbad
.
EJ^ Export Results
-• ^ jas;^-~ G^ ^-^^(^ -^ ^"-^ ^^^- ™ -fa "A- ^™- - -^ ^ 1
State 5andrDrtv!nayariiabl**Ilrt.Sfudy c , „
Dissolved org. toxicant: [Esfeitualorato]
-ablle sed. detritus
lefrac. sed. detritus
Susp. and dissolved detritus :
Sailed labile JiBtrltus
Juried refrac. detf itus
Small game fish: ILargemouth Bass, TOY)
.arge game fish; (Largemouth Bass, Lg]
\ak«fe Vofwrte -'.--=- •
LigM -" ^
' Temperature ,
! Wind Loading
2-1
-------
AQUATOX USER'S MANUAL
CHAPTER 2
Open the file Esfenpond.aps, if it is not already open. We will remove the macrophyte
compartment by highlighting it in the list, clicking on the Delete button, and confirming the deletion.
When the change is made, you will see a warning that the Control Run is not current. The control
run provides a basis of comparison so that the effects of the perturbation can be determined.
Likewise, state variables can be added by clicking on the Add button and choosing from the
list. Let's add macrophytes back to the list of state variables.
Inseit State Variable
Select State Variable to Insert:
Sand
Silt
Jti
* 1_^
Cancel
m •ml
Note that the names of the taxonomic groups and ecologic guilds on the main study screen
are followed by the names of the specific groups in brackets. We have to specify the type of
macrophyte by highlighting Macrophytes and clicking on Edit, or by double-clicking on
Macrophytes. That will give us a double screen representing both the macrophytes and the
associated toxicant. Click on Load Data to load a specific plant record for macrophytes. In this
example, Chora andMyriophyllum are the only macrophytes listed; we highlight Myriophyllum and
click on OK. If there is no selection made you will receive an error message indicating that there
is no data associated with the state variable Macrophyte.
Default Fila C Other File
Asterionella
Attached blue-greens
Blu«-gr«ens
Chara
Chlorella
Cryptomonad
Cyclotella nana
D«f*u tFllfr- PiantPDB
Periphyton, Diatoms
Portphyton, Greens
OK H X Cancel
2-2
-------
AQUATOX USER'S MANUAL
CHAPTER 2
Initial Conditions—To continue with our macrophyte example, we should enter a value for the
biomass of macrophytes present at the beginning of the simulation; if the value is left as 0 and there
is no loading, then macrophytes would not be simulated. The initial condition will depend on when
the simulation starts (which is specified in Setup). In this,example we will enter a value of 0.1 g/m2,
which is appropriate for Myriophyllum in a temperate pond at the beginning of the growing season.
Macrophytesi [MyridphyllUmJ*;,- ;
Initial Condition:
•«t - Toxic Chemical Exposure?
'••'"- - <• "(of Macrophytes)"'
~r
Loadings from Safiow:^^
'Use Constant Leading of
<~ Use Dynamic Loadings:
Use Dynamic Loadings
Date I Loading „ ,
Date* '," j Loading
Multiply loading by p
t V \ & * -v^\ ~,\
,--«•"'.- SZ', '^. ] Import
< 'Multiply loading by }1
sssr ^— -** s *
, 1 toa
-------
AQUATOX USER'S MANUAL
CHAPTER 2
The Initial Conditions screen provides a useful way of displaying all state variables. In
order to avoid conflicts with other windows, you cannot edit the initial conditions in this screen; that
is reserved for the loading screens.
State Variables' Initial Conditions
Jug/L
0.08 mg/L
0.05 mg/L
0.05 f mg/L
1.5'mg/L
12;mg/L
3 g/sq.m
3 g/sq.m
(LIIBjmg/L
fl.72jnig/L *
0.02 mg/L i
0.08: mg/L
21Kg/cu.m ,
2.Kg/cu.m ,
3 mg/L
3Efi|mg/L
0.2'mg/L
Djug/kg
0 ug/kg
0 lug/kg
0 ug/kg
Ojug/kg
Q i ug/kg
Parameters—These provide values for coefficients in the process equations. Although default
values are given, the user has great flexibility in specifying values to represent site-specific species
or groups. We already have seen the screen for chemical parameters as an example of using the
Library. Instead of loading the general library record, we could have loaded the study-specific
record by clicking on Chemical or by double-clicking on Dissolved org. toxicant in the state
variable list and then choosing Edit underlying data. In the following examples we will examine
a record from each of the other libraries. A record can be down-loaded into a study from a library
by choosing Load data on the Edit State Variable Data screen.
We will examine first the parameter screen for plants. Choose Plants from the Library
menu, then move to Cyclotella nana (this is a common diatom, but we could just as easily have
chosen Diatom and gotten more general parameter values). Two fields near the top of the screen
require explanation. If you click on the arrow to the right of Plant type, you will be given a choice.
The choice of Plant type is important because different types have different physical or biological
processes that apply to them. For instance, phytoplankton are subject to sinking, but not periphyton,
2-4
-------
AQUATOX USER'S MANUAL
CHAPTER 2
which are attached to a surface. Conversely periphyton are limited somewhat by very slow current
velocity; but not phytoplankton., which are adapted to still water.
Less obvious is the Toxicity Record; again, clicking on the arrow to the right of the field
will give you several choices. The intent is to associate the organism record with one of the limited
number of organisms for which there might be toxicity data or procedures for estimating toxicity.
In this instance, if you choose Diatoms the model will utilize the toxicity data (e.g., EC50) for
Esfenvalerate to Diatoms, as listed on the Toxicity Record portion of the Chemical Properties
screen.
fAQUATOX- Edit Plant
Inorg C Walf-sSpatian \ \, 0.054".t*>D/j~ |C & W83, p. 39 (greens)
Temp IJesponse Slope'pi?Wi *--j/ ~
OptimumTemperaftire f «,s 10,*C jCollins&VVIosinski B3,p.43-21
,3* *- ~3* I v *"J ~" <
,." "jcaWB3r
Maximum'"Jfl?nperature-j ;^_ 35s,"o
! *I" ," "*/•."' . ' -"I "'
i yfii'Adaptatian Tem'p> I 35 *<;
' ». • ~~. ^Hfir
Max Photosyufheti* Rats j 7T> JU11,
s^ ^/-j, * iS—z: -^
"_ RespiratftnCoefSgdnt \t
-------
AQUATOX USER'S MANUAL
CHAPTER 2
Next we will locate the record for Ghironomid from the Animal Library. Click on Animal
Type to see the pull-down menu. Chironomids have aquatic larvae, so Benfhic insects is chosen;
this is important because emergence is simulated by AQUATOX for insects as a loss term, but does
not apply to other animals. Note that the drop-down menu for Toxicity Record here includes an
Other selection. If there is no clear association and you have toxicity data, you should choose
Other and enter the data under Other in the Toxicity part of the Chemical screen. Click on the
scroll bar to the right to see the rest of the Plant screen.
Banthtc Insact jrj! Toxjcity Record |Chir ^ ^ ^ I ^> ^ f J^
Carrying Capacity | " lOfitig/L jobs, blomassLakeEsrom, Den. ^; »,^ -
Scroll down to see the rest of the screen. The trophic interaction table is important because
it defines the food-web relationships and assimilation efficiencies. Freshly sedimented
phytoplankton are an important food source for chironomids; these are modeled as labile sediment
organic matter in AQUATOX. The Bioaccumulation Data section contains parameters relevant to
bioaccumulation of organic toxicants, only one of which (Initial fraction that is Lipid) is sensitive.
The model is not sensitive to the longevity of the insects because emergence is a function of growth
rate, which depends on local, seasonally varying conditions. Likewise, mean weight can only be
approximate across all instars because it will vary greatly during the growing season.
2-6
-------
AQUATOX USER'S MANUAL
CHAPTER 2
- -iiiinii-!-
Oatnete Mortality \ <*,
Coefficient I ' "0.001, |/d - [minimal, L&P'BO genera) value I"!" '7> •via'!- •"* ' *" "f " '
w ' " ' ' - • "--* «-*«'*•»•*' • -
- -• 0.02 '
-zz**1*-""
3 Capacity • | ' _ iO,jgj/l,,' "sJoJiSjWonfass'U
"v ,v x,^ i-' Traphfc
Sed Refractory Ofilntus j
Sed. Labile Detritus
SParticulate Refrac, Dftntus^
Partwulate Labile 0«ntos,
, "Diatoms
1 " "Waerophytas''
Oetntiyorous invertebrates
^afiii¥Dtdua Invertebrates
^'PfeWtory Invertebrates
I" '"forage Rsh
- Small Game Fis
0.01
0.99
. ' °
* \'N 0
.Cs- ?
— - >i<*
,:< ro
••
- <*?
,4. * *
^ - * f * ^
.^ '
,,,«
1
, ' ' 0.3
^ifs ~ \
/,¥ ' o-5
- 0.-2
0.0
„ ,'02
^^ >•
'
'
*
,
filter feed by means of web
selectively filter feed mostly floe, layer'
-=-,«- sl ~ - ,-~i>
'K',"-- '^-/ia
" *" , /.'":™3vT,,' J. " "~
V. ^!^i'st
^ ^ •*, »
. *. - ""^" f
- -3 " ' "/ .
, '/ ^:s' -" ~4
X1*" •)» * x ~*"" j,1*^
» " ,« K'JJAS -~
if ~ . !
V ' " .
*"' S *!>!.! 14
f* •«*
-' Bioac'cumulation fiata: —
lylean age or Ijfetime *f- ^ ,365 day^|multtyear to L. [Esrpm (Berg et al. 1962)
Initial fraction that is EJpid n -0.05
(Wef Wt.)
Meanweigjlf 1 "^ 0.0075 g JHatidbookof Enyirori.Data i
- ~ > "-^S0^
Finally, we will examine the default remineralization screen. Because the parameters are
global there is little need to change them for a site, unless the organic material is quite different or
there is some reason that the microflora might have adapted to abnormal conditions, such as a
thermal spring or acid mine drainage.
2-7
-------
AQUATOX USER'S MANUAL
CHAPTER 2
Remineralization Data:
References
PQt. Anaerobic Sad.
NH<, Aerobic Sed.
65,'C
|no longer used "^
jtemperature at which degradation meat
| Alexander, 1961 ~~
jno longer used
JLyman et al.fl2;Francls et al. In Hendrej
Ityman et al., B2j.
0.018 • fra,c. |Redfleld "55 ratio
0.079 i frac.
0.575 ratio jWlnflelit et al., 71 & Redfleld 58
4.57' ratio jScavia W
0.15 g/m-d {Collins & WloslnsM B3 (0.69)
Ojg/nfd (redundant
9Z g/nrfd jEfller et al. 1967, p.695 (mg or g?)
Max Degrdn, Rale,Labile [ 0.0153 jg/g-d |Gunnison 1S3S,p.63(phytaplankton) •
Max. Degrdn, Rate. Refrac, | 0.0049 |g/g-d JGunnlson 1985, p. 63 (conifer needles)
Temp. Retponse Slope
Optimum Temperature
Maximum Temperature
Min Adaptation Temp.
Mm pH for Degradation
Max, pH for Degradation
Organics to P
Oiganics to N
02 Diomass, Respiration
O:: N, Nitrification
Detmal Sad Rate
*,>>
•ar^e <$ ,-f *^
/{-^,, ,', »xt> ,
'•••* i » Vf >,,
Loadings—Double-click on Dissolved org. toxicant or on the Chemical button on the main screen
to bring up the Edit Chemical Data screen, and to examine the various options for loadings to the
system. Pollutant loadings can be entered as constant or dynamic loadings in several different forms.
The pollutant can be entered as a concentration in the dissolved phase (or loosely bound to
suspended sediment); the water inflow and the site volume are then used by the model to compute
the loading per unit volume. The gas-phase concentration is used to compute atmospheric exchange;
ordinarily concentration in the atmosphere can be considered to be 0, although some pollutants such
as PCBs may have significant atmospheric concentrations.
Point-source loadings are mass per day (g/d) for the entire site; they are divided by the site
volume to obtain the loading per unit volume. In this example, dynamic loadings from a point
discharge as calculated by the PRZM model are entered. Note that the dynamic loadings are
interpolated, so if the intent is to represent a spike such as from storm runoff on a particular day, then
the loading should be bracketed by "0" loadings. The model assumes that the loadings "wrap
around" with an annual cycle and that the last loading can be interpolated to the first loading as if
it were in the succeeding year. Exercise caution when modeling multiple years, but you only have
loadings data from one or a few years. Sporadic loadings, which would only be expected in that one
particular year, may inappropriately be repeated in successive years. If you do not wish loadings to
be repeated, enter values ("0" or otherwise) for the first and last days of the simulation. The dynamic
loadings in this example were entered by hand; an excellent alternative is to download or prepare
2-8
-------
AQUATOX USER'S MANUAL
CHAPTER 2
a file external to the model and import it into the study using the Import button. This procedure is
described in detail later.
Another potential pollution loading source is from direct precipitation. These are given as
g/m2 d because AQUATOX does not explicitly consider precipitation. Click on N.P.S. to toggle to
the non-point source screen, which is in g/d.
t Sources
Use DynainlcLqadings —-*•
^DtssoWed'org, toxic
Mode) Run'
Perturbed,!
Control I
Bate I Loading j,±i *
^12/25/1994
12/26/1994 _?-D421 '
12/27/1994" " D.13289
12/28/1994 DJ1B517
>12y29/1994" 0 ,' -
v 'Multiply loading fey [53
loadins froin Direct Preciitation
ff UseCatist,L
-------
AQUATOX USER'S MANUAL
CHAPTER 2
AQUATOX- Edit Slate Variable Data
Macrophytes: [Myriophyllum] ^
Initial Condition:
J0.1 [g&q.m _
Loadings from Inflow:
Loadings: '/ *, „ /
" <• Use Constant Loading of
»,
£„,
»/.i
2-10
-------
AQUATOX USER'S MANUAL
CHAPTER 2
Perhaps the most confusing, yet flexible, loading screens are those for suspended and
dissolved detritus. In an effort to minimize data requirements, the screens combine several
compartments: suspended and dissolved refractory and labile detritus, defined as percentages.
AQUATOX will make the appropriate conversions from BOD, organic carbon, and organic material,
and partition them among refractory and labile particulate and dissolved fractions to provide input
to the model run.
&' fn&tf^amoiiJIjjjfpaiticafale Kfieirjt'ciSiy;|ij|8?
rp-*""^r'•••/^^^"•••'-""'T-'"^^ : • • •' -.AS-^.-x--
2.2 Sites
Selection—Several default sites are provided as part of the AQUATOX database. These can be
edited and additional ones can be created in Library mode. They can be loaded into a Study by
clicking on the Site button. The Site Type is used at this time to indicate a baseline extinction
coefficient for the water and, for streams, to enable computation of discharge-related characteristics;
it does not serve as a filter for the site choices that are presented when one chooses Load Site from
DB.
2-11
-------
AQUATOX USER'S MANUAL
CHAPTER 2
it- _.'. :-.-., f-uifc Stsvjr, &*
AQUATOX: Study Information - ^
State and Driving Variables In Study
Study Hamr. JESFENWERATE, POND
Model Run Status:
Perturbed Run: No Run Recorded
Control Run: No Ctrl. Run Recorded
Data Operations ' Program Operation?
Dissolved org. toxicant: [Esfcnvalerato]
Ammonia
Nitrate
Phosphate
Carbon dioxide , ,m^.
'; j
Eorturbac
£h«mlcal
Control !
SIX
»f, HftfJ a"1?"1 |
"SfiT —-—--r ! in—— S_=B?
J|ll Sjtup I i !|B^ Export Rwuhs
O*l Holts ' f 13». Export Control
»*' i »£ ii
Site; Missouri Pond
Edit Underlying Data
, Load Site From DB
Remlnerallzatlon
! Reload Rentln. From DB
Slta Type:
T; L'ake
'{"•'Stream
C Reserwolr
CrUmnocorral
Wind Loading
fidd Ffieftte
Default File r, Other File
Corn Belt Pond
Default Lake
Default Pond
Default Reservoir
Default Stream
Dor Israel Pond
Duiuth Enclosure
E F Poplar Cr TN
EF Poplar CrTN #3
Kansas Pond
Lake Ontario
Missouri Pond
Monticello stream .
NOnKAMIXDN PA
Default Fie- Site.SDB
2-12
-------
AQUATOX USER'S MANUAL
CHAPTER 2
Site Characteristics—Each site can be characterized by a small number of site constants. These
can be seen and edited by clicking on Edit Underlying Data in the Site Data window, or they can
be loaded from the Library. There is some redundancy in that Volume, Area, and Mean Depth
all have to be specified. Based on mean and maximum depth, the bathymetry of the site is
computed. Volume is a state variable and can be computed in a variety of ways (accessible through
the volume loading screen); however, one option is to set it to a constant using the value provided
in the site screen (see 2.3 Driving Variables).
Both epilimnetic and hypolimnetic temperature parameters have to be specified, even for streams
and ponds, where they can be set equal. Given observed annual means and ranges for temperature
and light, seasonal fluctuations are computed. These are not computed from the latitude because of
local and regional differences in elevation, cloud cover, and maritime or continental climatic
conditions. Latitude is used to compute the seasonal variation in day length. The Max. Length is
the distance, usually the long axis, across which wave buildup can occur; it determines the depth of
mixing in stratified systems. Some variables are not used at this time and are so indicated.
AQU AT OX- Edit Site
«, f^^psisJL*' * £,~»jl|& »^|
^I^Mnl-lis
. Max length (or reach) j- 0.779 -km ^ 4Eftl8l;Santl Ha'rnett, 1996, p. 3
11 sr^s w) i -i3iD°r°m3 *.' i^i"!"'19^!-^:'
Surface Area I 12000000 »?-',
' Mean Depth j •<_'- loT, ?, ,-//.
' Maximum Depth | ' 19.5 m , •
Ave .Epilimnetrc'j
^Temp
13 "0,^ JOwensana Effler,*1996;f.'207 -r,
Epiljmnetic Temp I f 57 «c U'il'V '' ; ?'Vj-' *•*
-/ - Ranoe,! „. ,- \*,,~
Ave Hypolirrmetjc r
'
Temp I ,—
Hypolmtnetie r
^ Temp Range j ,
- Latitude f-
Anni/a! Lfem Range I,', "430
If modeling a stream, information on the type of channel and slope can be supplied by clicking on
the Stream data button.
2-13
-------
AQUATOX USER'S MANUAL
CHAPTER 2
2.3 Driving Variables
The traditional driving variables (light, water temperature, wind, pH, and water volume) are
listed with the state variables on the Study Information (main) screen. This was done because it
simplified the data structure, and it provides for expansion of the model to compute these variables
using differential equations. As mentioned above, light and temperature are computed from annual
means and ranges using simple sinusoidal functions. They also can be specified by the user as
constant or variable loadings. The Edit window is called by double-clicking on the appropriate item
in the list.
Use Annual Mean and Range Loadings
Use Constant Loading of
Ly/d , .,
C Use Dynamic Loadings:
2-14
-------
AQUA.TOX USER'S MANUAL
CHAPTER 2
As a default, wind is computed using a complex Fourier series of sines and cosines for a 140-
day repeating period with a user-supplied mean value. Dynamic loadings of observed values can
be entered or imported. At this time pH is a site constant or loading.
AQUATOX- Edit State.Variable Dala;
Eft'«
£:•- ' T^f^^^ !
f^*' v4»^Ius8?BifaMltTiB)e Series5^*" ^ «*#&•* 'f " ,"^".1,^;!S^ , 5?^' , -^'
H'^i*"''^.^P^^^?,?*"^0'^'"*,': ' •-' .iw.-.:^-
"*."-'',' '*'•'.• , ^jUs^ft^rfainic Loadings:;-.; ;:J^^|!h-*'*T'';''.:? - ,-;
s??"': --^
K -.;:>-.•.*
^..s^Siwv
^b^1^-9 -. -.---.^.^ : - - • — "VV^ . y •.•v.-^ ..^-aa^MfK- -.
.jl^te-Tf: ;; t /rV ^gy^^^^V.
Vrf , ' ' rf>| ^.Ix"^!^'^'Tl '^^f/¥^' '***'*„!/- X
r;^S«9^«Sft.
jm
yjj^^tijl
^^s^^'^^^^Z-^^jS^^M^m'^
2-15
-------
AQUATOX USER'S MANUAL
CHAPTER 2
Inflow, outflow, and changes in volume can be represented by a variety of options. In this
simple example, the volume is kept constant. Although inflow is provided as a constant, it can be
overridden by the model if there is insufficient inflow to offset evaporation (an annual site constant
set by the user). Likewise, discharge is computed to maintain the volume with high inflow. An
example of dynamically specified volume will be given later.
' inflow Q£ water
(• Use Const. Loading of [15
Use Dynamic Loadings
Water Volume
Initial Condition:
p Use Manning's Eqiiptfpn^trcsms only)
(• Keep Constant at Initial Condition Level
Calculate Dynamically
Utilize Known Values (below)
Date I Loading
Multiply loading by ]1
Multiply loading by I1
Get Initial Condition from Site Data
2.4 Setup
Before you execute the model, you should check various settings by clicking on Setup. At
the top of the setup screen you can modify the first and last days of the simulation. Use a 4-digit
year designation to avoid any confusion between the years 1900 and 2000; the model will interpret
"700" as "72000." The Data Storage Step defines how often the results are saved; it is usually one
day, but can be varied to save space or show high frequency results. AQUATOX interpolates
variable-step output to obtain the desired interval. The Relative Error is the acceptable error in the
simulation; if it is not achieved in a particular time step, the variable Runge-Kutta routine decreases
the step size and tries again. If the relative error is too large, the results may be erroneous; if it is too
small, the run time may be too long. Usually a value between 0.005 and 0.0005 is appropriate, but
you may wish to experiment for a particular application.
2-16
-------
AQUA.TOXUSER'S MANUAL
CHAPTER 2
Study Setup
yi First Dajtlf Study
^ mast Day 05/01/199;-^ ,
'""* ""*~*
Storage Step^f .Ofl
<7~:- <^^2.S - - , ^v^t^v ' ) •* • ft "
Relative Error >OJ050,;t ~/ Minimum StepsFz^ iE-llfc^
Contaminant Constant
N
tjiji" S~"!? ,
ipid Calculation* -*
__£"._ Disable
s Write Hjipoip,
Include Coinplene'd -Tok? itrBAF Calculations
What follows are three choices for computing bioaccumulation factors (BAFs) and a choice
for saving output. If you wish to compute steady-state BAFs, you may wish to hold the freely
dissolved contaminant constant; this was done in an application concerning PCBs in Lake Ontario
(see Volume 3: Model Validation Reports document). AQUATOX calculates time-varying lipid
fractions in fish, but those calculations can be disabled and default or user-supplied initial values can
be used. The older literature often did not distinguish between freely dissolved contaminants and
those complexed with dissolved organic matter. You may choose to include the complexed
contaminant in computing BAFs so that the results are directly comparable with the older literature
values. In plotting output for stratified systems it is usually more pleasing to plot continuous values
for the hypolimnion, even when the system is not stratified. This is done by duplicating epilimnion
values for the hypolimnion when the system is well mixed; however, that takes additional storage,
so you may choose not to duplicate those data points.
Fugacity and kinetic partitioning are grayed out because the model only represents kinetic
partitioning now. If you click on Show Integration Info, you will be able to see what tune steps
are used in solving the differential equations and what rates and associated relative errors are causing
the integration to slow down while the model is running.
2-17
-------
AQUATOX USER'S MANUAL
CHAPTER 2
Percentage of Maximum Stepsize
Last Error Overrun:
T H2O(ug/L)
You may save biologic (and chemical) rates for examination with a spreadsheet program.
Choose Save Biologic Rates and click on Rate Specifications to designate those state variables for
which you want the additional output. Don't save rates for all state variables or the output will be
voluminous! Usually you would save rates for each output step, by choosing When Writing
Results. However, you can save rates for each step in the solution of the differential equations, that
is, Each Attempted Step. You also can choose to save just the errors associated with each state
variable. These latter choices are useful only if you are concerned with the details of the numerical
analysis.
FBe Type to Write Rate Data to:
Paradox FBe (>.*) C, DBase File ('.dbl)
Track Rates for these vars:
CO2
3xynen
Rdetrsed(gAn2)
Ldetrsert(g/m2)
Fldetrdiss
Ldetrdiss
Rdetrpart
Ldetrpart
ff -WIumWriUnB
Results
C Each Attempted
Bl-greens
Macroph(gftTi2)
D invert
Hinvert
P Invert
Fflsh
3 fish
Sm g fish
I nnffch
WrHe All Rates
Associated with
V <&•* i X Cancel'
Uncertahity and Control setups are complex and are covered under Applications.
2-18
-------
AQUATOXUSER'S MANUAL
CHAPTER 2
2.5 Output
AQUATOX takes advantage of the Borland database engine to provide a rich selection of
output screens. Click on Output in the main screen to see these. Unfortunately, because of the
complexity of the data and the number of output configurations, it may take several minutes to
format and load the output on a slower computer.
Tables—First let's examine the Perturbed Simulation table. It gives the values for each of the
state variables using the reporting step specified in the Setup screen; the default step is one day. The
first row in the table gives the initial conditions.
jf&AQUATOX-- Output
("Perturbed SimulationI Perturbed Toxics| Control Simulation! Control Toxics| Perturbed Graph j Control Graph j Difference Graph |"Perturbed Hypo. SurnllJ_£.
f» •*,£, "" ,~«*\ &artrjptu!ieifZimritatinn*r&taia}/strttthfaKR~ NN , *•'•
Lil*sed(S)taaRdelrsedaft2MLd*dlss Rd*dlss Ldelrpart Rdeir
2-19
-------
AQUATOX USER'S MANUAL
CHAPTER 2
The Control Simulation presents the results of a simulation without the perturbation. In this
way even subtle, indirect effects can be discerned. Furthermore, comparison of perturbed and
control runs ensures that consistent evaluations are obtained without undue concern with how well
calibrated the model is for a particular site.
AUUAIUX Output
Sljy'jjdjjrnulaljonj jjHtotb^foxlgjjamttol Simulation | Control Toxics I PeOwbaA Graph ] Control Graph | Difference graph | perturbed Hypo. SumJLJlL
Print \ Control Simulation: State Variables I FSaonsinmgfL unless
TpsmSOFSaftef™^ OWaUWfrOxWsWff
2-20
-------
AQUATOX USER'S MANUAL
CHAPTER 2
The Perturbed Toxics and Control Toxics tables give masses of toxicant associated with
each compartment or carrier (in |ag/L, mass per unit volume), total mass, time-varying half-lives (in
days), concentrations (in ug/kg, ppb), and rates of degradation, volatilization, and loadings (in \igfL -
d).
Control Simulation] QmW Toxics] Pst
~
Contro^^jph j Difference Graph | Perturbed fljrjjo.^MBiilL
" ,- ,
, _ --^ -^,- „ ,
' ^ *-
2-21
-------
AQUATOXUSER'S MANUAL
CHAPTER 2
Graph—Limited graphing capability also is available. Click on the Perturbed Graph tab and you
will get a default graph for the perturbed simulation with representative ecologic guilds. By double-
clicking on a given point on a line you will get label for the line and value for the particular point.
Poilmbed Simulation | Perturbed Toxics | Control Simulation{ Control Toxics"' Perturbed 6fa|ih | Control Graph ]'Difference Graph | frerturbetl tiypo^Sum*.
1^ yl
Oiganlsms in mg/L, toxicant In pgfL unless olhemise indicated /f / * * t
View rtypo&nnfon
Print Setup | Print Chart j
ESFENVALERATE, POND (PERTURBED) 01/30/2000 8 09 47 PM
J
^mefiwa^i^i^i^mms^^i^^^mwmim
08/28/1994 10/27/1984- 1SOS/19S4
CEplilmrforv segment) DATE
The color of the lines and symbols can be changed by clicking on the hammer (tool) icon and
selecting Palette Bar. The color can be dragged to the line (the cursor becomes a fill symbol to
indicate the procedure). Be careful that the fill symbol is on a line and not on the background, or you
will change the background! The scale can be changed by clicking on the magnifying glass icon,
and changing the maximum scale value. The titles and axis labels can be changed by clicking on
the icon labeled "ab" and changing the appropriate text.
You will probably wish to change the state variables plotted, so click on the Change
Variables button on the upper left. You can highlight one compartment, or you can highlight
several choices in the list on the left at once by highlighting the top one, moving the cursor down,
and pressing the shift key and the mouse button together. Clicking on the IE symbol will move the
choices to the window on the right. By clicking on the 0 symbol you clear the list on the right.
2-22
-------
AQUATOX USER'S MANUAL
CHAPTER 2
AQUATOX-- Select State Variables to Graph
<-- * .
Available State Variables;,'
, -» -, ss «.» -
1vv**" Slate Variable* Jo Giaplgr,
-" ~
T H20(ug/L)
NH4
H03
P04
C02
Oxygen
L detr sed[g/m2)
R detr sed(g/m2)
L detr diss
R detr diss
L detr part
R detr part
BurLDetr(kg/m3)
BurRDelr(kg/m3)
Oth alg(g/m2)
Macroph(g/m2)
P invert
Bfish
UTalor Vnl !«-•• ">1
1, -Jjfl*
Diatoms
Bl-greens
D invert
H invert
F fish
Sm g fish
Lg g fish
Click on the Control Graph tab, and you will get a comparable plot of the control
simulation.
^
nulationl PDrturbed Toxics 1 Co
fSf, '/^ , ti.Vw t'lrL ^_ _ . _,
7 CofeoiGfipE"!Difference.Graph I perturbs
2-23
-------
AQUATOX USER'S MANUAL
CHAPTER 2
By clicking on the 3D icon you can get a ribbon graph. Another option is an area graph. "A
picture is worth a thousand words," so experiment with the other icons.
'SAUUATOX-. output
Pmluibud Simulation | Pjrturbed LISxlHljCSS*?1 S|mu}atlon|
-''-'-"" ..... " ----- "— -" — • ---- =-~~:~-^=-~ -- ^ --- "~~ — ~^;-..~- — ^^ir^ -
cs j Perturbed GJ-aph^ [Co^l'Gpfh|p!jfgj-gnc8
*" ^fl'^v. n rv^^v** ^swSL/siyt^^ ^vSZ-vfe^t — ^
ESFENVALERATE. POND fCONTROU 01/30/2000 8 09'47 P%/(", .
Oenfl/1994 10C7/I994 12/26/1994 B2C4/IB9S
(Ep&nnlon Segment) DATE
X f o i
2-24
-------
AQUATOX USER'S MANUAL
CHAPTER 2
More informative is the Difference Graph, which plots the percent difference of the
Perturbed minus the Control values for the state variables. It is an excellent way to isolate and
portray the direct and indirect effects of the perturbation. For example, in the pond study most
animals were affected by chronic and acute toxicity to esfenvalerate. However, the detritivorous
invertebrates (amphipods) recovered quickly. The forage fish (bluegill) rebounded in part due to the
abundant amphipods and benefitted from decreased predation from the large game fish (bass), which
did not fully recover during the year-long simulation.
___ ssi
BrturbBd toxics I Control Simulation
•?-, *£f*r -*>"—
^.*'3.
A graph can be printed by clicking on the Print button. Print Setup allows you to specify
the printer and its properties. You also can save the graph to the Windows Clipboard by clicking
on the camera icon. If you wish better graphics, then you should export results to a file to be
processed by a spreadsheet program.
The model also can compute and plot or tabulate lipid-nprmalized bioaccumulation factors
(BAFs). Two methods are provided for the computation: the actual BAF based on a comparison of
the concentrations in the organisms and the concentration in the truly dissolved phase in the water,
and a computation based on a "dissolved" concentration that includes dissolved and complexed to
dissolved organic matter—the latter for comparison with older literature values that did not account
for complexed contaminant. The choice of computational method may be made in the Setup screen.
If you choose "Log BAF" from the list of available variables, the resulting plot shows that
2-25
-------
AQUATOX USER'S MANUAL
CHAPTER 2
esfenvalerate has a log B AF over 10 in forage fish (bluegill) at the end of the simulation, indicating
that is a highly bioaccumulative chemical, especially in a complex food web.
PBrtUibQrf'Slmulirtion[Wrtu^ |ControlGraph] Difference
qanooVni4ij!e« | Organisms In my L, toxIcarMnfig/LunSesstiihewlia Indicated
VtaWllypoliiTinlim | Print Setup | Print Chart |
ESFENVALERATE, POND (PERTURBpD) 01/3PCOOOS 10 17 PM _
Files—^You may wish to export the files for use in another program. From the Study Information
screen, click on Export Results, to export the results of the simulation with the toxicant, or Export
Control. The default will be in dBase cft/format, which is limited to eight upper-case letters in the
column headings. The full headings will be exported if you choose Paradox db format, which is the
native format of the AQUATOX data structures. A third option is to export as delimited ASCII files
suitable for importing into almost any spreadsheet.
Note that the library databases, saved in the Database subdirectory, also are in Paradox
format. To read and edit them with a Paradox-compatible program it is necessary to rename them
with a db extension, instead ofsdb, cdb,pdb, or adb for site, chemical, plant, and animal databases.
Don't forget to change the extension back before attempting to use it with AQUATOX.
2-26
-------
AQUATOX USER'S MANUAL
CHAPTER 3
3. APPLICATIONS
The following examples are intended as illustrations of potential applications. AQUATOX
has been validated with several data sets from diverse sites and applications; however, like any
complex model, it should be evaluated for the intended use. More detailed reports on model
validation, including analysis of model predictions as compared to observed data, are found in
Volume 3: Model Validation Reports. No warranty, either expressed or implied, is made.
3.1 Nutrient Enrichment
AQUATOX has its roots in what was basically a eutrophication model, and it provides a
reasonable representation of the effects of nutrient enrichment. It can be configured to depict a
complex food web that is both phytoplankton- and detritus-based, with both game fish and bottom
fish, which are very important from the standpoint of protecting aquatic life and fisheries. It also
reports phytoplankton both as biomass and as chlorophyll a, which is an important index of water
quality. Dissolved oxygen is another important index that is computed. The Secchi depth, an
indicator of clarity, also is estimated.
For our first example, we will use data from Onondaga Lake, New York (Onondaga.aps),
The lake has been described very well in a book edited by Effler (1996). It has received municipal
and industrial wastes for many years, and effluent from the municipal wastewater treatment plant
accounts for nearly 20% of the annual inflow to the lake (Effler, 1996). Of particular concern are
the combined sewer overflows (CSOs) that carry storm water and raw sewage into tributary creeks
about 50 times a year. In 1991 there were 45 CSOs discharging into Onondaga Creek, 19 into
Harbor Brook, and 2 into Ley Creek. In a separate report, Park (1999b) described three levels of
analyses in validating Version 1.66 with Onondaga Lake data. For purposes of this example, we will
use the third-level implementation with detailed loadings for nutrients, a site-specific mixing depth,
and compartments parameterized for cryptomonads and rotifers.
Discharge data from the four gauged streams in the watershed (Onondaga Creek, Ninemile
Creek, Ley Creek, and Harbor Brook, listed in order of importance) were downloaded from the U.S.
Geological Survey Web site (see Table 1). Discharge from four ungauged streams was estimated,
assuming that they had an aggregate flow rate that was 94% of the discharge of Ley Creek and
Harbor Brook based on data in Effler (1996, p. 102).
3-1
-------
AQUATOX USER'S MANUAL
CHAPTER 3
Table 1. Input Data for Onondaga Lake Simulation
Variable
Inflow
Phosphorus, NPS
METRO
NOX&NH3, NPS
METRO
Org. matter, NPS
METRO
Epilimnion
temperature
Hypolimnion
temperature
Wind
Solar radiation
Initial conditions
Source
www.waterdata.usgs.gov
(note: URLs may change)
Effler 1996, calc. from p. 162
Effler 1996, calc. from p. 159
Effler 1996, p. 162
Effler 1996, calc. from p. 138
Effler 1996, calc. from p. 128
Effler 1996, calc. from p. 138
Effler 1996, calc. from p. 138
Effler 1996, calc. from p. 128
Effler 1996, calc. from p. 138
Effler 1996, p. 207
Effler 1996, p. 247
Effler 1996, p. 248
unpub. data, Lake George,
N.Y.
Effler 1996
Format
daily values for 4 gauged streams;
extrapolated to ungauged streams
mean annual cone., 7 tributaries, 1989-
1990; mult, by respective inflow
mean loads, April-September, 1990
mean annual concentrations for 1989
for 4 tributaries
mean annual loads for 1989
back-calculated from organic-N
mean annual loads for 1989
monthly interpolation from figure
monthly interpolation from figure
mean value est. from figure for 30
years
observed annual mean and range
obs. data and professional judgment
The loadings were then computed using average concentrations for the respective streams,
assuming a constant relationship between concentration and discharge. Different average phosphate
values were used for 1989 and 1990 for Onondaga and Ninemile Creeks, which varied considerably
between the two years due to combined sewer overflows. Also, the concentration of ammonia in
Ninemile Creek, which flows through soda ash waste beds, exhibits an inverse relationship to flow
rate according to Effler (1996, p. 131); therefore, his Equation 3.12 was used to compute the
ammonia concentrations:
= 0.20 +
0.73
Flow
where:
3-2
-------
AQUATOX USER'S MANUAL
CHAPTER 3
[T-NH3]
Flow
concentration of total ammonia (mgN/L),
flow rate (mVs).
The computations were performed in a spreadsheet by first converting the discharge data
from cfs to m3/d and nrYs then, for the nutrients, multiplying by the given concentrations to obtain
mass per day (g/d) in successive columns. The loadings were imported into AQUATOX by clicking
on Import in the Edit State Variable screen and choosing the appropriate comma-delimited (csv)
or database file.
F2 "'"it ,-vil
5
1
S
9
"10
1f
12
13
Ye
17
18
71
22
-23
24
25
26
27.
"30"
31
"32"
33
34
35
"36.
~3B
fj).
~~*IX~
ffi
A,, [ 8, j . C , ! % D .J E-rJ- ' T .1' -6
#Station number 04240010 , __
# latitude (ddmmss) 430327 .
# longitude (dddmmss) __07_60946
# state code 36
# county _ Onondaga _
#hydrolpgic unit code . 04140201
# basin name Seneca ^
# drainage area (square miles) 110 ,
# contributing drainage area (square miles)
# gage datum (feet above NGVD) 362 29
#base discharge (cubic ft/sec)
#WATSTORE parameter code _ D0060
SWATSTORE statistic code 00003
# Discharge is listed in the table in cubic feet per second
# '
# Daily mean discharge data were retrieved from the
# National Water Information System files called ADAPS
#
# Format of table is as follows
# Lines starting with the # character are comment lines describing the data
# included in this file. The next Mine ^ is ja row ^ of tab-delimiled column
Snames that are~Date and Discharge The next line is a row of tab-delimited
# data type codes that descnbe a 10-character-wide date (10d) and an
#8-character-wide numenc value_ftir dischargeJBn) All following lines are
#rows of tab-delimited data values of date (year month day) and discharge
#
# NOTE this file was requested from the NVV1S W software package
tfonTueSep 81740341998
# Dates are now in format.
:# "~ ._
i# — Date Range In File -
!# 101/01/1989-12/31/1990
Date Discharge Flags 2446 6 = cfs -> cu m/d p 128
10s 8n 2s cu m/d cu m/s NH3 g/d NOx g/d
101/01/1989 113 276.466 320 46399, 270.93!
-~»<
— -
— —
p 128 'p 159
DOM *TP
' 1,969819' 58^611*
Ready
3-3
-------
AQUATOX USER'S MANUAL
CHAPTER 3
Given the readily available hydrologic data, both 1989 and 1990 were simulated with daily
loadings. Examination of the loading plots confirms that the streams draining into Onondaga Lake
are indeed "flashy" or subject to fast runoff with distinct peaks; the nutrient and organic matter
loadings vary accordingly, except the ammonia loadings, which vary slightly from the other loadings
due to the inverse flow relationship cited above. The data files and plots were prepared using
Quattro Pro and Excel.
Onondaga Lake inflow
Onondaga Lake ammonia loadings
7,000,000
6.000,000
§" 5,000,000
J. 4.000,000
§ 3,000,000
H 2.000,000
1,000.000
01/01/89
09/24/89 06/17/90
05/14/89 02/04/90 10/28/9Q
1,800,000
1,600,000
1,400,000
§1,200,000
< 1,000,000
O 800,000
5 600,000
400,000
200,000
01/01/89 09/24/89 06/17/90
05/14/89 02/04/90 10/28/90
Results from preliminary model runs indicated that some of the model assumptions and
defaults were inappropriate for this application, and therefore needed to be modified. For instance,
the model computes the depth of the well mixed layer (epilimnion) using a robust regression
equation with the fetch (distance across which the wind can blow) as the independent variable; this
equation is based on a dataset for 167 lakes. In Onondaga Lake the computed mixing depth of 15
m is twice as deep as observed (Effler, 1996). It appears that salinity from industrial pollution in the
lake is restricting the mixing depth. By back-calculating from the regression equation, a fetch
(Length) of 0.779 km was found to give the observed well mixed depth (MaxZMix) of 7.75 m:
MaxZMix = Length0336 • 0.569
log(Length) = . .I, ' + 0.245
Length = 779 m
3-4
-------
AQU A.TOX. USER'S MANUAL
CHAPTER 3
The maximum length was then changed in the Site Characteristics screen.
Savjlllifaiy i^
SBeNama jOnondaga bake _
^.-i*,
-/e «, 'Site Data:
MaxLeglh^orrecli)
loforeeM5 rn wel(mtxe
s"*v Hypoftrnnetic
r " Temp Range
J8.7 iuoi( L, 'tfllft C
" •••-•-'•'
p J msq/C, Efflsi c» at
A second modification was necessary because the observed spring algal bloom was not
predicted in initial runs. The spring bloom was reported to be due to cryptomonads, a flagellated
algal group that was not in the default data set. Using values from Collins and Wlosinski (1983),
a cryptomonad compartment was parameterized. The present version of AQUATOX can simulate
three algal groups; diatoms and green algae are more important than blue-greens in Onondaga Lake,
so cryptomonads were substituted for blue-greens. This is appropriate because the model assumes
that blue-greens occupy the top meter of water unless the wind exceeds 3 m/s, when Langmuir
stripes form, and cryptomonads also tend to move toward the surface. Rotifers are important grazers
on cryptomonads, and predatory zooplarikton probably are unimportant in the lake, so rotifers were
substituted for predatory zooplankton. Furthermore, the food preferences for rotifers were changed
to force them to "eat" cryptomonads in the model.
3-5
-------
AQUATOX USER'S MANUAL
CHAPTER 3
AQUATOX Ed.IAmm.il
•mrwin»
Anlmi! jRotifif, Brachlonus ;|n ^
^ J*,
t'-P i .
• " '" " " " -. ' —•',', ^ * " rf •* f * « / r -
ArvimalType; jPolagiclnvart.
'JaB' Tpxicity Record JDaphnla '*£] ^ 'st, " ,'C*
? r^ A''' •*
Animal Data: KeAfm^K • ' "" '- , ^, .„„-.,-" , -/j?
Half Saiuralion Feeding iKs/l, IWalz. 1995, p. 441 " * „ ' l * /„ "> ' <-* *^
Maximum Consumption p
Min Pray fix Feeding P
Temp. Response Slope |
Optimum Temperature p
Maximum Temperature P
Min Adaptation Temp. |
Respiration Ra!« P
Specific Dynamic Action P
Excretion : Respiration P
Gamele* : Biomase P
Gamete Mortality P
Mortality Coefficient P
Exponential Mori, Coeff P
Carrying Capacity P
S^SBQlpd | (Collins iWlosliwW 1983, p. 45 T/, f *~< ™ ^ ,^» ^
0£
._^_ll
Hisf/7L |WaIz.1995,ji.441 _ ' •- J^T. , ~. ~ f t ,, ~ ^ j'
Wr-- " P"
. .,. ....... „ .^».™«_™^ ^Sil"3 ?"* !, - - ^ ^^J.
25.gQ_ ]Walz.1995,p.443 _,<^ ' 'fe^^fe, "<%, < ~ " { - **;:' "^ J"t
35' Jg '' [prof, opinion ^ — ^.^^ * - - v t r - **
2;i&L Jcoldjidapt«d(sa»WalZ,199S> ^^^ ''*,"",».*. ,*',," f"
034[rUcl |Uldy * Ploskay, 1980, p. D20 ^ /^' ' ~* ^ / ^
• o,[
0.17'J
' ^ -
0.18|
OIXM1
(unilless) HJ
!i..,^^,/ ' iL
is?-, r
duded In above _ _^» ' " ' , » •
''. s,- - ' - -».
•pfff |Walz.1995,p.445 -- "^ £'*' ^s? , ;fr*'f ""'4^
"H.d jquestionabts ^ „ ( ^^ ^ ^ ^ *
OiSipfd j*
/alz. 1995, p, 443 , _s ^^_ *„.,' '^"'"TT'*, -
JUajt/ajfeld )W«li.1995,p.442 ,_ ^ ^^ ^.J. -. ~" * •" (-^ " ' ^ ^
z*[
S»S J
6aen*to«.4lCCo-«ne.rr198Orp.26L,^ i/d J
ifl)alz.1995,p,_442 ^ ,' - ( ( ( ^ '.^, ' "
2-51'mg/L LoCren S Lowe-McConnDlI, 1980, p. 260 — «v» <•»>)' f
"" _,»^ W*" '"*
Trophic Interactions: - -- ,/' Tv'^
Preference: Eaaitlom Rflforcncoi: , ' "-"S**r , y^
ft»f*il (Sacftion) * ' . ^ " x < ,
Std. Refractory Detritus
S*d, Labile Dolriluo
Partlcutale Refrac. DolrSus
Particulale Labih Dotritus
Diatoms
Bhie-Gnana
Greens
Macrophylee
Detrilivoraus Invertebratee
Kerbivorout Invertebratee
Prtdatory Invertebrates
Forage Fish
Bottom Fish
Small Game Fish
Mean aje or lifslim
Initiil fraction thai is LJpi
(WetWt
Mean v/eign
0
0'
0
OA.
OJJS
US'
oxe
0
0:
0
0
o
0
-Si
Bioacc
* 1
0
0
0
8.15
0.15
0.15
0.15
D
D
0
0
0
0
0
" '" " "- ' ' ^.''ff , ..,« *
f *^ <<-»ft\ /- T ,- '^ ' ^-^" » f»-
$*' ' , ,._ " i.-,,*^ T
Walz. 1995, p. 438 v'^ii.. ' " ^ '' - If
if** i^-^^&r T t ' " ^- l»
"ciyplonionarfa j_ , . , , / |^
-t/ - 1 .* '.<-.''• •-, ' j"; • '"
•.-, T ' ^ *'^ '" /
* ^ r.^~"/" "^ .'" .•y
' „.. -i^iSK.*- . '1'sS? -
-« r^*? ir ,,',/T ' ''^
i T "" ~j ^. „ zjr^^y^C", *. -*i
umutation Data: ~ "7,*- -^<-* •„ ^ ,,^4}
<|aya|W8li.1995,p.442 -jy, ^~, ^ ' -J"* " T
-------
AQUATOX USER'S MANUAL
CHAPTER 3
In order to conduct "what if exercises with the model, we will set the control options to
remove point source loadings for nutrients and detritus (click on Setup then Control Setup). This
effectively turns off the contributions of the metropolitan sewage treatment plant. (Another option
would be to turn off the non-point source loadings.)
•*-' .^QU^rd*.' Study ftifomsQtion^
" I1" Mt^,,i! ^"-^ *t%*
Study Nat
'._ t s, StateranlH>iiX>!,ie}
oe(nft/s: -. sS
Zeto-OU Initial Condlttorre
OmUWIowLoadtnai:
OniKJ(>*KS!ion»t,iM«lii(i v .
N om« Direct prodp«WiM>I.Mi«iias > Fi, !
"
Om«Dlr!>clPiedr«tatl
-------
AQUATOX USER'S MANUAL
CHAPTERS
Other water quality parameters related to eutrophication and nutrients are also computed, such
as dissolved oxygen, Secchi depth, nitrate, ammonia, and phosphate. The user could perform similar
analyses with these parameters as was just shown with chlorophyll a. This would give a more complete
picture of the lake's responses to proposed nutrient control scenarios, and whether water quality
standards would be met. See Volume 3: Model Validation Reports document for a more detailed
discussion of the application to this highly eutrophied lake.
3-8
-------
AQUATOX USER'S MANUAL
CHAPTER 3
3.2 Contamination by Organic Toxicants
As the only general fate and effects model of potentially toxic chemicals in aquatic
ecosystems, AQUATOX is well suited for risk assessment of organic toxicants. An earlier version
was used in a comparative risk assessment of twenty-five pesticides. As an example, let's consider
the.ecological risk assessment of the pesticide chlprpyrifos in an experimental pond enclosure. Load
the study ChlorMed. aps and click on Chemical. You will see the Edit State Variable window. First
check to be sure that Gas-phase cone, is set to 0 and that the initial condition is 6.3 ng/L (we will
start the simulation with an initial concentration and no loadings). Then click on Edit Underlying
Data to get the chemical parameters. Click on Toxicity Data or page down to see the ecotoxicology
parameters. The lipid fractions for the organisms should be as shown below. When they are correct,
click on Estimate K2s (elimination rates) to be sure that estimates are up to date.(See Volume 2:
Technical Documentation for a discussion of K2s.~) Then save and go back to main menu to run the
perturbed and control simulations. If you wish to evaluate biologic rates, that should be done in the
Setup screen prior to running the simulations.
Load from felfe. f j Save to'cibfaiy
V * *! ^ *»* I f\\rif
? Esll|nal8K2sg{,- - / OX ft
N< T*1*' ^ v-.^ , j **;.,>
Rate &#.''' fjpfd ' ™References:
£.CiOftig/l)COMSi,(Wd) nme(hrs) (fraction) ^ '
Rainbow Trout ] 8.7008! j DJ3019 I 96 1 0.11 (Regression on Bluetjill ' "\
* r.^/~ ~ " ^ "^-' ^" ' ** / ^ *" / /
BWegill ) 2* | abB76] [ 5s | bis* jE!PASlu«tJB7|)v124^
_^BSSS ^ ] 9*487, ) 0.0033 ' |
^ ^ ,_™™__ y "" '
ih t &87.1736 . | O0037'|
Minnow
Danhnla
7.1736
Z03_ j.aOIBS
tO.<(7,| a0915
Chironiimid j. 1.4157 j tttiSSi
Stal% p "10* j JB.OM8
Ostracod ^2.0553' j 0.0693"
Amjlrfiiod | 0.29 j ttq693>
Other 1" ^T? 1 ^~5"i
sion on Bluegill
0.1 [Regression nit Blueglli
% 96' j 0.047 tpiolcombe et a!., 1382
TiT
24"
if - ptiotasyiiat "fjafe
Greens,-;! ~6" ! Ti4
0.06; |EPA,W,"p.42(Dulirth) '
0 05 ^jj^gressjori ortD|p|mia, '
~W I ol«r|MayeftaEliemWt*i1982
24 | 0.05^'JRegressi^n art Ojphfti?r.( "
"l^'j oSi". JEPA B7» p. 42 (Duluth) ^ ^
^r r~iuefP "T" ^^
SxfK, L!p!d~
r/ma fraction)
ClicK Hero to View Algae LC50 Data. |
^
•H&fJ
Miiinow
70JJ9'1 jlOltOftCSO
J , 10.15 _]S* oft<3B(,
-F'iuiisnr
. ,^ja,-'"
*«!" *^
\K < "
" r-vU' i>
. *J «4!!i«W •
1 !• r ,» ^ •< *a*s T, ^^s^l-* 1
I, '.'.S- V- ' —
!s- *™y> "'•t1' ., ,».
~>
-------
AQUATOX USER'S MANUAL
CHAPTER 3
The impacts are substantial when contrasted with the Control simulation. In the perturbed
graph the most obvious features are the immediate decline of most compartments with the exception
of the forage fish (minnows).
&AUUAIUX IJulpiH
•iTo^lLaiffi^Ji^Hi^Al^^SSS^^^i^sJ C<"S*^JE
~~~^,,_
'^^^^i^^^^^fMmm.
3-10
-------
AQUATOXUSER'S MANUAL
CHAPTER 3
In the control plot we see a normal progression as first the zoobenthos, then the forage fish,
then the small game fish become established hi this experimental system.
EJAQUAIOX" Output
'Perturbed Simulation jPerturbWTpx|c
7C>_Sc?**|*' *•?* ^pSS'" -
3-11
-------
AQUATOX USER'S MANUAL
'CHAPTERS
The difference graph shows the impact of the chlorpyrifos. It is obvious that a significant
fraction of the invertebrates are killed immediately. However, the effects on fish are more subtle and
interpretation of the output requires additional information.
t AUUAIUX" Uulnul
"§litiillallnn[ PerturbedToxIcs'rControl sTmulalioiiLcoii>fo|Tg«te[Pertur6ed Graph j ControliStaph"|l;!frprB|cBpap¥|'pgffliiicitt Hypa.<$nn
IpflrtSrtup |i PtintCturt [
The rates were saved by choosing Setup from the main screen, Save Biologic Rates, and then
Rate Specifications. The state variables and file type were chosen in the following screen. The plots
were produced using Quattro Pro, but any spreadsheet or graphing program could be used.
raoTypoloWrtoRatuOalato:
<-•- Paradoxntol'jfc) f PBas»HtoC.dbf>
3-12
-------
AQUATOX USER'S MANUAL
CHAPTER 3
Bluegill rates in control simulation
Bluegill rates with 6 ug/L chlorpyrifos initially
0.25
06/17/86 06/29/8607/11/8607/23/86 08/04/86 08/16/86 08/28/86 09/09/86
| Consumption4 HQ Defecation4 B Respiration4
]Excretion4 [tj Predation4 H Mortalitv4
06/17/8606/29/8607/11/8607/23/8608/04/8608/16/8608/28/8609/09/86
B Consumption4 Q Defecation4 | Respiration4
p| Excretion4 F71 Predation4 H Mortality4
With chlorpyrifos, the small game fish (actually bluegill young-of-year) immediately suffer
loss of food base; but, more important, the increase in defecation indicates chronic toxicity, which
is paralleled by decreased consumption in the simulation. There is no acute toxicity as indicated by
mortality, but the fish biomass declines steadily. Examination of the chemical record shows that
bluegill have a laboratory LC50 of 2.4 ug/L The fact that bluegill are not killed can be explained by
the rapid sorption of chlorpyrifos to sediments and therefore decreased bioavailability.
3-13
-------
AQUATOX USER'S MANUAL
CHAPTERS
Chlorpyrifos is abioaccumulative chemical. A plot of bioaccumulation factors indicates that
there is biomagnification up the food-chain and that steady-state has not been achieved for the fish
in the three-month simulation.
AUUAIUX Output
ji3grt}£ei%Lh«JJgxliaf^^ | Control Giapti [DiffDrnncB Graph ] PorturbBd Hj5>o._Siintjy
• Printchirt |
"ctji.RPYR)F08eugn-(pam!RBECo
i?9'XVMX?™JC'CHWft?XK!WX)Oro
l-<;i.;l^»-t iri ;l t I *.-».( »*«• jrt «(ijJ (fj t I t ^ t > t <•' '* **>*,*«> | i . . i )tt)i taf~* t,j(it»lltv> j^f^t i )
. 07/1M9S6 08/02/136S ^ x 03fl8/19S6 09/D3fl988 tBhgt
(Epfimnion Segtmsrt) DATE
3-14
-------
AQUATOX USER'S MANUAL
CHAPTER 3
3.3 Multiple Stressors Due To Agricultural Runoff
In our example, we will model a run-of-the-rivef reservoir receiving extensive agricultural
runoff and minimal municipal and industrial effluents (Park, 1999a). In the 1970s approximately
90% of the watershed of Coralville Reservoir, Iowa, was in agricultural land (MacDonald and
MacDonald, 1976). Water quality was so poor that the lake was referred to locally as the "Dead
Sea." We will use the reservoir study Coralville.aps as a starting point. Open the file, then click on
File and Save As, and name it AgricRes.aps so we don't write over the default reservoir study by
mistake. Also, change the Study Name to "CORALVILLE RESERVOIR" (this will be the heading
for the graphs).
Controlling Nutrients and Sediments—Because this reservoir receives a large quantity of
suspended sediments, we need to load observed total suspended solids (TSS). Clay, silt, and sand
are only available if the site is a stream. Suspended algae and detritus are subtracted from the
observed TSS and the difference is considered to be suspended inorganic sediments. These are used
in calculating the extinction coefficient and the Secchi depth.
Click on Add at the bottom of the state variable list and choose Tot. Susp. Solids. In the
main screen we then see this as an additional state variable.
Insert State Variable
Select State ^arjaifetb
Clay
Sand
Silt
Tot. Susp. Solids
gr™fl[£ ...... jl
^^^^tt^MMMMIWMMMMtaJ3
Cancel
3-15
-------
AQUATOX USER'S MANUAL
CHAPTER 3
£fe \.ttvy Stud*
AQUATOX: Study Information
SluUyNamo: (OIELDRIN, CORALVILLE
Model Run Status:
Perturbed Run: Ho Run Recorded
Control Run; Wo Ctrl. Run Recorded
Data Operations:
|;s|||[ fritlialConds.
<^6 Chemical
Silo
SfituP
Holes
Program Operations:
Eerturbed
Conlrol
Ojrtput
Export Results
Expotf Control
State and Driving Variables In Study
Dissolved org, toxicant: [OielilMn]
Ammonia
titrate
Phosphate
Carbon dioxide
Oxygen
Tot Susp. Solids
Labile sed. detritus
Refrac. sed. detritus
Susp. and dissolved detritus:
Buried labile detritus
Buried refrac. detritus
Diatoms: [Diatoms]
Blue-greens: [Blue-greens!
Greens: [Greens]
Macrophytes: IMyriophyllum]
Detritivorouslnvertebrate:;iChironorrttd]
Herbivorous invertebrate: [Daphnia]
Predatory Invertebrate:,[Predatory Zooplank.]
Bottom fish: [Buftalofish]
Forage fish: [Blueglll]
Small game fish: [Largemouth Bass, YOY]
Large game fish: [Largemouth Bass, Lg]
Water Volume
pH
Light
Temperature
Wind Loading
Double-click on Tot. Susp. Solids obtain the loadings screen. Then click on Use Dynamic
Valuation and Import to load the file TSSCoraLcsv.
Each line oflhe text file must
have a unique date enttyln the
form MWddW/Y followed by a
comma and then a loading
entry in the appropriate units..
3-16
-------
AQUATOX USER'S MANUAL
CHAPTER 3
Click on Initial Conditions to see the initial values for all the State variables. Dieldrin is 0
because we will let the model compute the concentration in the reservoir.
PJiosiohate
'Carbon dioxide
0.08 mg/L
4.9> mg/L
0.21 mg/L
12 mg/L
6.5 mg/L
20 mg/L
2.5 (j/sq.m
5 g/sq.m
0.5994 rng/L
0.0666*mg/L
0.0666 mg/L
0.0074 mg/L
2; Kg/cu.m
2 Kg/cu.m
0.05; mg/L
0.21'• mg/L
0.05 mg/L
Detritivorous invertebrate: [Chironomid]
Herbivorous invertebrate: [Danhnia1
0.1 rng/L
2 rng/L
Bottom fish: fBuffalofishl
Forage fish: [Bluegill] "•._
Small tiame fish: FLarqemouth Bass, YO'
Large game fish: [Largemouth Bass, Lg]
0.023 mg/L
0.1 mg/L
5 mg/L
2; mg/L"
0.230! mg/L
3 mg/L
0 ug/kg
0 ug/kg
0 ug/kg
0 jig/kg
0 ug/kg
0 ug/kg
0 Ug/kg
0 ug/kg
0 ug/kg
0 ug/kg
0 ug/kg
0 ug/kg
1200 ug/kg
0 ug/kg
0 ug/kg
0 ug/kg
3-17
-------
AQUATOX USER'S MANUAL
CHAPTER 3
Click on Setup and make sure that the simulation dates correspond to, or are less than, the
range of dates for TSS, 10/1/1973 to 9/30/1978. Be careful, if you enter "10/1/73" it will be
interpreted as "10/01/2073." Because observed TSS values are being used in lieu of dynamically
simulated inorganic sediments, the capability of the model to repeat a time-series loading should not
be used for TSS unless all other loadings, particularly inflow, are restricted to the same range.
Otherwise, the model will extrapolate the TSS beyond the observed dates and obtain unacceptable
estimates of suspended sediments. Note that the 5-year simulation may be quite lengthy on a slow
machine; you may wish to decrease the period.
First we will investigate the impact of nutrient reduction, most likely through best
management practices, without any change in loadings of dieldrin or inorganic sediments. Click on
Control Setup and uncheck all the Organic Toxicant controls, and check Set Multiply Loadings
Factors to 1.0 for Nutrients and Detritus. Then, going back to the main screen, double-click on
ammonia, nitrate, phosphate, and suspended and dissolved detritus and enter a multiplicative loading
of 0.5, if not already done, on the Edit State Variable Data screen for each. In doing so, we have
set the model so that nutrients and detritus will be halved in the perturbed run and kept unchanged
for the control run. Dieldrin will be present in both simulations. This demonstrates the power of the
control settings to set up various pollution control scenarios.
Zero-Out Initial Conditions
Omit Inflow Loadings
Omit Point Source Loadings
Omit Direct Precipitation Loadings
Omit Non-Point Source Loadings
Omit Toxicant in Organisms
Omit Buried Toxicants
Organic Toxicant:
Zero-Out Intial Conditions
Nutrients: (Ammonia, Nitrate, and Phosphate)
Zero-Out Initial Conditions
Omit Inflow Loadings
Omit Point Source Loadings
Omit Direct Precipitation Loadings
Omit Non-Point Source Loadings
Set Multiple-Loadings Factors to 1.0
' ' „ *«*•*•'
Omit Inflow Loadings : ;f /P
fe>mft:Point Source Loadings } :, '.," JT"
bri^i(D{rect.P^e9igit^in.t^^ijigs>/'' P
Omit'Non-pointSo^ul^alb.adli^s1';'' •' . ;r;P
Set Multiply-Loadings Factors to 1.0 f/;;.,
Ssnd/Sflt/Clay:
Zero-Out Initial Conditions
Omit Inflow Loadings
Omit Point Source Loadings ...
Omit Direct Pfiepipitatfon Loadings
Omit Non-Poiht Source Loadings
Set Muttipfy-Loadings Factors to..1.0
3-18
-------
AQUATOX USER'S MANUAL
CHAPTER 3
Run the simulation without any additional changess clicking on Perturbed and Control.
Select Output, and view the Control graph. Note that detritivorous invertebrates have a high
biomass, reflecting the large influx of detritus from upstream. Diatom blooms occur periodically,
with maximum biomass of about 16 mg/L during drought conditions in 1977.
SlAQUATOX-- Output
Perturbe'CStmulatiotiJ PerturbedTojfIc?|"CR(rtrolSimulationIjCrttrtwIJoxIcs] PejiitrhsdGraph,*Controlffrapti [oiffepiwce Graph1! ?8rturf>eHHypo- Sum.
|[_chanagy«rriiffle8J| ^ Organisms Inygg^L. toxeanim
View Hypolimnlon I . *f*
.Pritrt$«i }.'
CORALViLlf RESERVOIR (CONTR04
3- 19
-------
AQUATOX USER'S MANUAL
CHAPTER 3
If we plot Secchi depth we find that the minimum is 8 cm, with a maximum of about 2.5 m
and a mean of less than 1 m. Note that if you plot only one variable the graphing routine plots it in
black, and no legend appears. Also note that the label on the vertical axis reads "Concentration";
you may wish to edit this.
Parturbid Simulation | Porturbad toxics] Control Simulation | Control Toxics | Perturbed Graph Control Graph | Difference Graph'fPerturb^l Hypo.'Smri
|[SjrrioBV«cl;bte« j'| Oiaanlsms in m& L, toxicant In fig/L unless othaninse mtficstetf
DIELDRIN, CORALVILLE (CONTROL) 01/30/20009 12 17 AM ,
230 •
2M •
J.IO •
2.00 «
1.90 •
i.eo •
1.70 .
160 •
150 .
I 140 •
1,30 i
1,50 <
WO •
090 •
oeo •
0.70 •
oeo •
oso
040
030
020
010
000
07/26/1974
03/17/1976 01/11/1977
(epttennlon Segment) DATE
11/07/1977
3-20
-------
AQUATOX USER'S MANUAL
CHAPTER 3
Now view the Perturbed graph. The similarity with the Control graph suggests that few
changes would occur in water quality if the nutrient and detritus loads are reduced by one-half. The
diatom blooms are virtually unchanged. The most obvious change is a small decline in forage fish
(blue-gills), which is probably linked to a corresponding decline in detritivore biomass.
AQUATOX-- Output
Perturbed Simulation [ Perturbed Toxics] Control Simulation | Control Toxics^'PerSirbei
Control Graph j Difference Graph'] Perturbed Hypo. Sum
|rchan9eVariabteV]j - Organismstomg/Lftoxicant in fig/Ltinless otltsnosa wteterf j
View Hypolfmman ] ^ ^ ~- * N Print Setup j s Pnnt Chart j t>
CORALVILLE RESERVOIR (PERTURBED) OE/14C000 9 25 00 AM
**+ a -Diatoms
Bl-greens
I x '
^ A D invert
o H Invert
!n Fdsh
0 Sm g fish.
Lggfish
3-21
-------
AQUATOX USER'S MANUAL
CHAPTER 3
A better way to portray the changes is by plotting a Difference graph. Because we have set
the nutrient and organic loadings in the perturbed simulation to half the normal values, a positive
percent difference means an increase in biomass with decreasing nutrient and organic loadings.
(Remember that the Difference graph plots the percent difference of Perturbed minus Control.)
We also will plot bottom fish (buffalofish), which were so abundant in Coralville Reservoir that they
supported a commercial fishery in the early 1970s. Based on this graph and examination of
predicted rates for the invertebrates and fish, which were saved and plotted in Quattro Pro, we
observe that invertebrate detritivores declined slightly due to decreased detritus loadings; this caused
a decline in blue-gills, followed by declines in their predators, bass. Eventually, in the absence of
competition, buffalofish are predicted to increase. Caution should be exercised in interpreting
difference graphs; these are plotted as percent changes, and small absolute differences are magnified.
For example, due to the toxicity of dieldrin, bass exhibit very low biomass values, even in the
control. This can be seen by plotting just the fish in the control simulation.
Perturbed Simulation | Perturbed ^^Joxlre|c^oi Sltnu^o^|_Con(rol Toxics |P8rtMrb8<) Graph] Co
Difference Graph IfertiTrbe'd Hypo. Sum < l>
I/1973
03rt7rt975 Ofrttrt977 11/07fl977
OATS
3-22
-------
AQU ATOX USER'S MANUAL
CHAPTER 3
BlAQUATOX-- Output
Perturbed Simulation j Perturbed Topics] Control Simulation] Controrfpxtasl Perturbed™Graph Control Graph%]piJFeri»nce Grapfi ["Perturbed Hypo, Sum...
f7 ~—*.„.--.[ ^ -i
Chanae Variables I Organisms in mg/LJoxicant in ug/L unless olhamisa indicated * f . ' <
1 I , „%„.„ «,u» rA'f-'^T ^
View llypolimnion | w ^ > Print Setup | 'PrintChart | ^' " J. . ^ '^"
OORALVlLtE RESERVOIR (CONTROL) 06/14/2000 3 39 03 AM
3-23
-------
AQUATOX USER'S MANUAL
CHAPTER 3
If we plot the difference graph for the key environmental indicators, oxygen, Secchi depth,
and chlorophyll, we see that halving the nutrient and detrital loadings improves the water quality
only slightly as indicated by slightly decreased chlorophyll levels and slightly increased Secchi
depths.
KAOUATOX- Output
Peituibed Simulation | PerjurbidTo^te|
,.u^,<»&,«sax~*. „ x,,*.- * i.^.
d GraPh 1 Confrol Graph prfferBtTciTGraiili | Perturbed Hypoi'§«ni_lLt
CEp4w4xi.il strolTied)
PrlntSrtup I'
SUFI [aaiiiuiigM«?iigi|Lii|tii
CORALVILLE RESERVOIR
fn Oxygen
chioroph tu^fl)
3-24
-------
AQUATOX USER'S MANUAL
CHAPTER 3
Having seen the effects of halving the nutrient and detritus loadings, let us now investigate
the effects of suspended sediments. In this run-of-the-river reservoir most of the suspended solids
are silt and clay, and most are from upstream. In the unlikely event that best management practices
were to halve the TSS without altering the other pollutants, what would be the impacts on the
Coralville ecosystem? This is easily analyzed with AQUATOX. Close the Output window, open
the Setup window, and choose Control Setup: Now uncheck the Nutrient and Detritus choices.
In the main window double-click on each of the nutrients and suspended detritus and set the
multipliers back to 1.0; then double-click on Tot. Susp. Solids and set the Multiply loading to 0.5.
Then click Perturbed (but do not run Control) to obtain a run that is perturbed only in that TSS is
one-half that in the control.
Click Output and plot Secchi depth, chlorophyll a, phosphate, and nitrate in the Difference
graph. By decreasing TSS, and hence inorganic sediments, turbidity decreases, and phytoplankton
are not as severely light limited in the simulation. In turn, phosphate decreases—almost certainly
becoming limiting for the phytoplankton. Chlorophyll a does not increase significantly, probably
because of grazing pressure by invertebrates.
EJAQUATOX-- Output
Perturbed .Simulation ] Perturbed Topics j Control Sihmtatlon I Control Toxics | Pertorbejl Graph 1 Control Grand 0I«8r8Rbe GrapFI Perturbed Hypo,
1 -1 * „ * •" "" ~ ~* "-^™* ™ ~ i™ r ™ • t * ~v *~r N ,_, _^ | *,
(Epilimnion, it stratified)
.
Print Srtap['PrintCtiari |
3-25
-------
AQUATOX USER'S MANUAL
CHAPTER 3
Controlling Pesticides—Next we will examine the effects of the dieldrin independent of the
nutrients, detritus, and TSS. Similar to the example of esfenvalerate in the pond, we will use the
perturbed run to simulate the toxicant and the control run without the toxicant. Therefore, close the
Output window, then set the multiplicative loading for TSS back to 1.0, open the Setup window,
and choose Control Setup. Now set the remaining-options back to their original state, with all the
Organic Toxicant choices checked, and the Nutrient and Detritus choices unchecked.
Organic Toxicant:
Zero-Out Initial Conditions
Omit Inflow Loadings
Omit Point Source Loadings
Omit Direct Precipitation Loadings
Omit Non-Point Source Loadings
P.!™! T95!.i?aI[*.'J?_0I8.?.n'sms
pmit~Buffed"fbxicants|
Set Multiple-Loadings Factors to 1.0
Nutrients: (Ammonia, Nitrate, and Phosphate)
Zero-Out Initial Conditions J~"
Omit Inflow Loadings T
Omit Point Source Loadings J~
Omit Direct Precipitation Loadings T"
Omit Non-Point Source Loadings F"
Set Multiple-Loadings Factors to 1.0
icmd/S/ft/C/ay:
Zero-Out Initial Conditions
Omit Inflow Loadings
Omit Point Source Loadings
Omit Direct Precipitation Loadings
Omit Non-Point Source Loadings
Set Murtipfy-Laadings Factors-to 1.8
Detritus:
Zero-Out Initial Conditions
Omit Inflow Loadings
Omit Point Source Loadings
Omit Direct Precipitation Loadings
Omit Non-Point Source Loadings
Set Multiple-Loadings Factors to 1.0
T
T~
f"
("
T"
T
3-26
-------
AQUATOXTJSER'S MANUAL
CHAPTER 3
Click Perturbed and Control to re-run the simulations. The perturbed graph shows the
effects of dieldrin on the default state variables. You can plot other variables by clicking on Change
Variables.
AQUATOX- Oulput
Perturbe'iTsimwTatlon | p¥rturbjp!fpxfcs|^Sntrol Simulation'] Control Toxics
change variables Organisms in trig/ L, texifantmfig/L unless othew/ss indicated
| Control Graph ] Difference Grapti j.Perttjjfcetl Hypo, Sum
View Hypptimmon
Print Setup Print Chart
, . CORALVILLE RESEgVOIR (PERTURBED) 06/14/200010 55 15AM
1
-------
AQUATOX USER'S MANUAL
CHAPTER 3
The control graph shows the seasonal patterns in biomass without dieldrin. Note that forage
fish (bluegill) are relatively important throughout the simulation, in contrast to the pattern shown in
the perturbed graph.
P«ltuihetf Shmilatlanl j>ertobe|;Bxte] 3Jn
-------
AQUATOX USER'S MANUAL
CHAPTER 3
The differences between the perturbed and control graphs are emphasized in the difference
graph. The difference is obtained by subtracting the control biomass from the perturbed biomass,
so negative values indicate relatively low biomass values in the perturbed simulation (in other words,
in the presence of dieldrin). The decline of all fish except the hardy buffalofish is easily seen. The
chironomids (invertebrate detritivores) benefit from the decreased predation and exhibit positive
values.
fl?ff
-------
AQUATOX USER'S MANUAL
CHAPTER 3
From these results, we postulate that the decline in fish is a combination of direct and indirect
effects of dieldrin. We can examine the rates for largemouth bass by clicking on Setup in the main
screen and Save Biologic Rates and Rate Specifications, then choosing Lg g fish prior to running
the model. The rates will be saved, with Paradox format as the default, in the Output subdirectory.
The rates can be plotted in a spreadsheet program. In this example, consumption declines due to
chronic toxicity and loss of bluegill forage base, and mortality increases in part due to acute toxicity.
Defecation increases due to the modeled effect of chronic toxicity on assimilation. This illustrates
the use of biologic rates for analyzing cause and effect relationships.
LARGEMOUTH BASS, CORALVILLE
o
10/03/73 12/30/73 03/28/74 06/24/74 09/20/74
11/16/73 02/12/74 05/11/74 08/07/74
| Consumption4 |H Defecation4 ^ Respiration4
| | Excretion4 Mortality^
3-30
-------
AQUATOX USER'S MANUAL
CHAPTER 3
Controlling All Pollutants—Finally, we can examine the effects of decreasing all pollutants from
agricultural runoff simultaneously in the perturbed simulation. Dieldrin was set to zero and the
nutrient and organic matter multiplicative loading factors were set to one-half. As we have seen
from the above applications, there are many complex interactions, and comparing the perturbed and
control graphs is difficult.
Zero Out Initial Conditions'
Omit Inflow Loatltnas , -
Omit Point SourceLoadings .
Omit Direct Precipitation Loadings
OmitNon Point Source Loadings
, '.•iSo'-o'uhriltlal Conditions ''•-
k pmitjnitaw Loadings ' r,
""' bn^t ^nt Source Loadings ; ' -'
ZeroOut Initial Conditions,^",
ng"""*?-"
Omit Inflow Loading
Omtt Point SourceLtradlnqs -
Omit Direct Precipitation Loauing
Omit Won Point Source loadings
set MUltlDV Loadings Facldrstd
SAQUATOX- output
*—1^—^^^^^^^^^^"^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ ~ • ~ ^ ~ irrmmlTTTlTTlr «-~ ru..,,.. ...m,. n n. rn......m m _. ^r-^r-rT-™^^^,^^-r^,T^_^ ^ ^ ^l
Perturbed Simulation | Perturbed^Toxfcs] Control Simulation) Control Toxics Perturbed Graph j Control'Graph | Difference GfapfjJ Perturbed Hypo.sSum^ilL
(change Variables' | * O(ganfett)s m mg/L, taxicsniinfig/L unfess othewise indicated
" Print Setup | Print Chart |
View Hypolimmon
CORALVILLE RESERVOIR (PERTURBED) JB/14/2000 12 1853 f|M_,,/_J_
3-31
-------
AQUATOX USER'S MANUAL
CHAPTER 3
However, the difference graph provides a direct comparison. Bluegill and bass increase
significantly in the absence of dieldrin. Chironomids decline due to increased predation pressure.
The buffalo fish exhibit a long-term decline due to loss of chironomid forage because of increased
competition. Algae, herbivorous zooplankton, and labile detrital sediments (not shown) are relatively
unchanged.
Portuibod Simulation | Perturbed Toxics | Control Simulation | Control Toxics ^Perturbed Graph j Control Graph Difference Graph | Purturbetl'tlypO' S«mjj±.
Print 6e
-------
AQUATOX USER'S MANUAL
CHAPTER 3
To better determine the effects on water quality, we will plot several environmental indices
in a difference graph. We see that chlorophyll a is generally slightly lower with nutrients halved,
oxygen is slightly increased, and Secchi depth is slightly improved.
HAQUATOX-- Output
Pertwrtmtj Simulation') Perturbed toxics] Control Simulation j Control Toxics) Pj^urbedjgraph j Control Graph Difference Graph j Perturbed Hypo. S«m JXi.
HfVflP J" , ' ^ _^t
ij, PjjntChart
j Change Var;iib;eii"j|
(EutlimraoMtstfalifietj)' -
-SOU ,, .,,.
10(Qtfl973
. 03fl7f1976~ 01/!1fl977 , 11/07/1977
DATE • * s v<"
In conclusion, AQUATOX can be used to analyze complex relationships in impaired
ecosystems and to suggest the relative importance of various causes of impairment. In this example,
dieldrin was shown to be a very important stressor. The simulations suggest that external loadings
of nutrients and organic matter are far less important; and, based on the model, halving the loadings
might not improve water quality significantly but might decrease the productivity of sport fish.
Therefore, this ecosystem model has the potential not only to help identify stressors, but to assess
possible environmental management scenarios as well.
3-33
-------
-------
AQUATOX USER'S MANUAL
CHAPTER 4
4. UNCERTAINTY ANALYSIS
Until now we have dealt with deterministic simulations. However, there are numerous
sources of uncertainty and variability in natural and polluted aquatic systems. These can be
represented easily in AQUATOX (see Volume 2: Technical Documentation), although access to
the additional analytical power is not obvious to the casual user. The key is to click on the Setup
button and choose Uncertainty Setup. We will go back to the ESFenPond study for this example.
Fii^tDayofStudp
-' "
D#fr Storage Step 1,00
Keep Fiody Ditiolved Contaminant Conitant .. « - -
mic Lipitl Calculation* . ^^^^vs.^ ^ J
iV Save Biologic Ralot
4-1
-------
AQUATOX USER'S MANUAL
CHAPTER 4
That will open a window that lists either all variables subject to uncertainty analysis or those
variables already chosen for analysis. We will display all variables. Because AQUATOX uses a
Latin hypercube sampling algorithm, it requires far fewer iterations than a brute-force Monte Carlo
sampling. Therefore, the default number of iterations is 20. This is probably adequate for an
analysis involving a single variable; however, it should be increased as more variables are chosen
for analysis. If you wish to replicate the sampled values in successive analyses, you should choose
a non-random seed for the number generator and keep it the same.
Run Uncertainty Analysis Number of Iterations 120
Utilize Non-Random Seed
Henry's Law Constant <«tm. mA3ftnol) jHormal
SedJDetritus-Water Partition Coeff. (mo* Normal
Normal
normal
Normal
Normal
Normal
Normal
Normal
Normal
Normal
Normal
Normal
Normal
Normal
Normal
Normal
Normal
Normal
Normal
Normal
Aoroblc Mlcroblil Dcgrdn. (Lid)
Unortah/zed Hydrolysis (Ud)
Photolysis Rate (Ud)
Trout: LC50(un/L>
Cattish: LCSO (U()/L)
Minnow: LC50(U[)/L)
D«ph,nla:LC50(ug/U
ChlronomldiLCSO (eniL)
Slonefly: LCSO (ug/L)
6«tracod:LC50(uaJL>
ftmpfipodY LCsb (ug/L)
Other: LCSO
-------
AQUATOX USER'S MANUAL
CHAPTER 4
By double-clicking on a variable the distribution can be displayed and edited. The lognormal
distribution is the default for loadings. The user can accept the default distribution parameters or
change them. The graph will show the results of any changes. The mean values are derived from
the underlying parameter sets, but altering them in the uncertainty screen will not change them in
the database and the deterministic simulation.
C: Normal v^l, Z
\C» ^
•*• ,i"'0'a673?lrf.r- '5;
Piiaftabilit^v5 i Cumulatwe)i)!striultin^
- ..s- .- .••,- <-,- *:•/-.. ••-•-•'
In an Urfcettainitf B
, -,«( ,-, -.^"JSST^.'v -N'*^ '••
OUse Point Estimate! ••'-. , ,
-- -'
Let's use that distribution to vary the multiplicative factor for point-source loadings of
esfenvalerate in water. For each iterative simulation the model will sample one value from the
distribution and use it as a multiplicative factor for all dynamic point-source loading values.
4-3
-------
AQUATOX USER'S MANUAL
CHAPTER 4
Click on OK, which will take you back to the list of variables; then choose to display only
those that will be varied in the uncertainty analysis. Be sure that the button in the upper left is
checked to Run Uncertainty Analysis (that button is a convenient way to toggle between the
deterministic and uncertainty options without disturbing the individual distributions).
17, Run Uncertainty Analysis Number of Iterations 20
Utilize Non-Random Seed
Param. 1 Param. 2 Param. 3 IParam. 4 Used?
ffJQnV Display Utilized Dlstribj
r Display flllDIstribs.
4-4
-------
A.QUATOX USER'S MANUAL
CHAPTER 4
Close the Study Setup screen by clicking on OK. Back on the main screen we see that
there is now a message in red in the upper right indicating the number of iterations chosen. That
message only appears when the uncertainty analysis is enabled.
llAQUATOX-- Foi Windows: "ESFenPond.aps"
*\k 3 <*>>
3^
.Study Name: "
Model RlinlStatus: *"
~ ^ ^ _, '!»>i/
Rerturbed Runt No Run Recorded 3-
1 /Control Rjhm No Ctrl. Kurt Recorded
3X: StudyInformation
(and Drivipg^r^Je|Jr^||^dy-j! ;VT^ '
_ I ^T"l#
Data Operations:
Initial Cohds.
Chemical
STfte s-
M"T
' ":>-.-• -»•'» i8*?--—-
^ /sa -, , _' -
: .^^Motes- I
, •v . ',
Program Operatiot
Control
Stutpjit, «j
x'^^^^^^W
f Expert Control
w
uncertairrfyiterations,
jl, A. * ^^'"
Dissolved -oriiy^lcan^psfenval^itel'
Ammonia _^ " <+>'"'' " *•,_
Nitrate '' ',-$~~~
Carbon dioxide
Oxygen -X^1'-1 ",
u.
Refrac. sed. detritus
Susp, and dissolved detritus :
Buried labile detritus ' ^ '
Ofttomsfpatorhsl ^ *-*" "*'7J
Blue greens: [Blue-greens] 'w_
Greens: [Periphyton, GreensJ
Detrititforous invertebrate: IChironomidJ
Herbivorous irvvertebrate: [Daphnia] , ,
Predatory invertebrate: {Predatory Zooplar
nnnnm Aeht.rr'ii&.M - * - , •i-vift i
SJottqm fght
t , ^
Small game fish: [L argemouth Bas|t, YO'W ^ ,
i^ ^i^ (K-^^ •'"^"n^^ M ^r' rk" » * ~
game fish: [Largemoutn Bass, LgJ ,;
y' ^
JfieldlS1 T ~v Edit
^'^K^BS'W^ ^ Jsa* t«i^ ««« tetta*
^^
4-5
-------
AQUATOX USER'S MANUAL
CHAPTER 4
When you click on Perturbed or Control you will be asked to give the output file name and
location. The folder to Save in will be given as the Studies folder, which is active; you might wish
to change that to the Output folder. Be sure to specify the extension "dbf' or you will get an error
message.
lutput Uncertainty Results As:
Save ]n: j€3 Output
Filename: JLJESFMult.dbf
Save as type: j DBase Format (*.dbf)
;1 j
, - * . — , i^toZtowp »*», "
SSL
i
i
»
r
iSJIf^fave/ |-
jj|j. if',',, "Cancel j
~"V P- '"" -• S , „ J r
Because of the voluminous output, it will be split into three separate files using the root name
that you provide. Ordinarily, you will not have to concern yourself with the supplemental files.,
which will be listed in subsequent Save operations.
Output Uncertainty Results As:
- Save in
t*
Output
Tox_UESFMult.DBF
Tox2_UESFMult.DBF
UESFMultDBF
f File name:
r-
Save as type: j DBase Format f.dbf)
The model will perform a deterministic simulation first to provide a baseline. Then it will
cycle through the uncertainty iterations.
4-6
-------
AQUATOX USER'S MANUAL
CHAPTER 4
The results of the uncertainty analysis can be viewed by scrolling to the far right tab in the
Output on the main screen, and clicking on Uncertainty Graph. (If you have not run a simulation
or if you wish to see the results of a different simulation, you may choose to View a Different
Database.) Only one state variable is plotted at a time, with separate curves for mean, minimum,
maximum, mean - one standard deviation, mean + one standard deviation, and deterministic results.
These are the distributions of the results for that particular state variable and are not necessarily a
reflection of the distribution of the sampled input variable. For example, the maximum loading of
esfenvalerate would almost certainly result in the minimum biomass of the large game fish, but the
benthic fish that is graphed is most likely responding to decreased predation. You may choose to
View a Different Variable, such as the concentration of the toxicant in the dissolved state. The
default Y-axis label assumes that you are plotting biomass, so it should be changed to units of
"ug/L" if you plot toxicant concentration.
4-7
-------
AQUATOX USER'S MANUAL
CHAPTER 4
PlffiBrianca^raph IfcerturboFHypo- Summary | Control Hypo. Summary:
'- — - ---- — -- - ' " - ~<~ ""-
4-8
-------
AQU ATOX USER'S MANUAL
CHAPTER 4
iigAHUAirbx-'oulpui
[Control Toxics I Perturbed Graph | Control Graph | Difference Graph j Pertui
.
View » Different Dstotinno
, ViowlnoD«t«infiIo:
I
K*aDsvj
s V-j
Similarly, we can vary the input values for other variables by sampling from the appropriate
distributions. For example, we have two values for the Henry's Law constant for esfenvalerate: a
measured value of 6.1E-8 and a calculated value of 3. OE-6 (ARS Pesticide Property Database). Why
not just use the measured value? Unfortunately, the constant is not easily measured, so the
calculated value may have as much validity as the measured value. Therefore, we can use a uniform
distribution defined by the two values, with equal probability of any value over that range being
chosen. Henry's Law constant helps control the bioavailability of organic toxicants, so the
sensitivity to a range of possible values is of interest.
~T5OT~ ----'- i"v_, 4*™
?>^V»? ^^>,_%v ^ ^V |
4-9
-------
AQUATOX USER'S MANUAL
CHAPTER 4
The results of varying just the Henry's Law constant for esfenvalerate are shown in the
Uncertainty Graph for large game fish biomass. The spread of values, although not appreciable, is
due to the differences in bioavailability and therefore differences in amount of toxicity.
J AQUATOX--Output
~\ r-JJ
View • Different Database
Vtewlno D«t« In RlK D:Wquatox\AQTX169Wutput«ESFUniforin.dlJf ^HntSSBip
4-10
-------
AQUATOX USER'S MANUAL
CHAPTER4
In another example, we will vary a critical parameter for the large game fish, bass, to see
how it affects the response of this important species. The most likely maximum consumption rate
is set at 0.055 g/g-d based on application of an allometric equation that relates consumption to mean
weight (Hewett and Johnson, 1992); however, there is considerable variation reported in the
literature (Leidy and Jenkins, 1977). The extreme values reported are 0.015 and 0.07. We could
take these as the constraints for a triangular distribution, but that would mean throwing out the
lowest and highest observed values because the constraints have zero probability. Therefore, we will
extend the constraints by 10% of the observed values. .
The results of varying this one parameter indicate that the model is not sensitive to
it—probably because the chronic and acute toxic effects dominate the simulation.
4-11
-------
AQUATOX USER'S MANUAL
CHAPTER 4
AQUATOX- Output
"Control Graph] Difference Graph |j Perturbed Hypo. Summary] Control Hypo. Summary Uncertainty Graph :
JTlTf
** y™"
Vtow * afferent Database
Organisms In m&L, toxicant in pgfL unless otherwise indicated \
•/ r
Viewing D*ta In Rle: D:\Aquatox\A«TX169\OutpuraESFTrIang.dW i Print Setup
DATE
In the final analysis we will examine the effects of varying mean depth of water in the pond.
A normal distribution is used with a mean of 1.2 m and a standard deviation of 0.4. The minimum
depth simulated was 0.097 m, and the maximum depth was 1.86 m.
The macrophyte biomass is sensitive to water depth. As rooted vegetation, macrophytes are
well adapted to shallow water; the maximum biomass is at the minimum depth. However, they are
probably light limited at the greater depths simulated in this turbid pond.
4-12
-------
AQUATOXUSER'S MANUAL
CHAPTER 4
IlAQUATOX-- Output
rContrBij^ragjj I DfffetenreJBrapri J Perturbed Hypo, Summary j Control Hypo. Sun«W«fiNi.|^ft6*«^W9l^'|.*-^^ ^3j
WalrfHte^A^ 1.
|[yiewauOTCTBnty»riatilej[
tt
^•s
4-13
-------
-------
AQUATOX USER'S MANUAL
CHAPTER 5
5. DATA CONSIDERATIONS
AQUATOX has many possible loading variables and process-level parameters. What input
data are most critical for the simulations? The answer depends on the goals of the simulation and
the site-specific requirements. By using the principles outlined above in Uncertainty Analysis, one
can perform sensitivity analysis to identify the more sensitive parameters and loadings for a
particular simulation. Sensitive parameters may require site-specific determination or careful
calibration. Some sensitive variables were suggested in the above analyses, others have been
identified in other studies.
5.1 Toxicant
• The octanol-water partition coefficient is critical to bioaccumulation in organisms and
partitioning in detritus. It often can be estimated better than it can be measured.
• Henry's law constant is important for volatilization and yet is often difficult to measure.
• Chemical and microbial degradation parameters determine the persistence in an ecosystem.
If only half-lives are reported, they should be represented as uncatalyzed hydrolysis rates,
which are not affected by seasonal conditions as are microbial rates.
• The thickness of the active layer, represented as the mass of sediment detritus, is important
because of the simplifying conceptualization in this version that treats sediment-water
interaction of contaminants as very efficient but restricted to the active layer.
• Some toxicants, such as parathion, may bind more tightly to sediments than indicated by
organic partitioning. Estimation of the sediment partition coefficient may need to be
overridden with observed values.
5.2 Nutrients and Remineralization
• The fraction of phosphate that is available depends on the nature of the phosphate loadings.
The model distinguishes between detrital loadings, with implicit phosphorus content that is
more or less available depending on whether the material is refractory or labile. Phosphate
loadings may be in the dissolved phase or may be bound tightly in mineral particles; the user
accounts for these by varying the fractional multiplier: 1.0 if the phosphate is readily
available and a small fraction if it is tightly bound.
• Release of phosphate from anaerobic sediments is a constant (during periods of anoxia) that
is set in the Remineralization screen (available by clicking on Site). Site-specific values
are appropriate where iron-dependent biogeochemistry processes are dominant.
• Co-precipitation of phosphate with calcium carbonate is not modeled. In sites where that is
important the best work-around is probably to decrease the loading accordingly.
• Chemical oxygen demand is not modeled explicitly because of its site-specific nature; a
work-around would be to decrease oxygen loadings.
* Constant stoichiometry for nutrients in organic matter is a simplifying assumption. One can
change the value of the ratio of a given nutrient to organic matter in the Remineralization
screen. The Redfield (1958) ratio is used as the default.
5-1
-------
AQUATOX USER'S MANUAL
CHAPTER 5
The proportions of refractory and labile and dissolved and particulate organic matter in a
system control the rate of remineralization. Inappropriate initial conditions will cause a
transient response, but poor characterization of loadings may affect the long-term nutrient
budget and bioavailability of organic contaminants. If possible, obtain seasonal values for
total organic carbon (TOC), dissolved organic carbon (DOC), and biological oxygen demand
(BOD, which is labile); these can be used to obtain the necessary proportions. Otherwise,
consider the source of detritus loadings (forests, treatment plant, etc.) when deciding how
much may be refractory and particulate.
5.3 Plants
Half-saturation constants for nutrients control how responsive phytoplankton and periphyton
are to eutrophication; parameter values may depend on trophic status.
Maximum photosynthetic rates determine the competitiveness and resilience of algae;
observed rates vary greatly and composite rates, such as for a diatom community, are most
appropriate for most applications.
The model assumes that blue-green algae (or any alga occupying that compartmental slot,
such as cryptomonads in the Onondaga Lake example above) float unless the wind exceeds
3 m/s; this makes the model sensitive to the mean wind loading.
Most macrophytes are sensitive to fall dieback; cold-tolerant groups, such as charaphytes,
should be so characterized with appropriately low optimal temperatures.
5.4 Animals
Consumption of refractory detrital sediments by zoobenthos increases the degradation rates
of those sediments, increasing the simulated sediment oxygen demand and remineralization.
The user should assume that most zoobenthos selectively feed on labile detritus, which
includes freshly sedimented algae.
The minimum biomass for feeding (Bmin) is seldom measured, yet the model can be very
sensitive to this. The BMin value protects prey from being totally consumed, but if it is set
too high the predators may starve to death. It may require site calibration.
Half-saturation for feeding is very seldom measured, but it can significantly reduce predicted
feeding rates. Therefore, it should be set low in the absence of data.
Consumption and respiration rates in fish are functions of body size. Most default values are
based on application of allometric equations presented by Hewett and Johnson (1992).
Selection of representative mean weights for use in the equations is important.
Mortality rates may vary greatly from one site to another. This often becomes a calibration
parameter, especially since death due to predation is separate in the model.
If modeling an aquatic insect that emerges, be sure to select "Benthic Insect" in the drop-
down list hi the parameter screen because otherwise emergence will not be simulated.
5-2
-------
AQUATOX USER'S MANUAL
CHAPTER 5
5.5 Inorganic Sediments
• Inorganic sediments are not explicitly modeled for standing water and only roughly for
streams. This simplification reflects the model's emphasis on nutrients and organic
contaminants. If sediment transport, burial, and scour are important, the model should be
coupled to a hydrodynamic model such as EFDC.
• Total suspended solids are used to back-calculate suspended silts and clays in the model.
Because this is a loading that is compared with phytoplankton biomass in the computation
of Secchi depth and light extinction, it should be provided for the entire period of the
simulation (most loadings can be repeated automatically if the simulation period is longer
than the available data).
5-3
-------
-------
A.QUA.TOXUSER'S MANUAL
CHAPTER 6
6. QUALITY ASSURANCE
AQUATOX is designed to facilitate documentation of assumptions and data sources for
specific applications and to archive results. Note fields are provided for the study and for each of
the state-variable loading screens. These are intended to provide the user with a way to record an
overview of the study and to describe sources and salient features of the loading data. Furthermore,
almost every parameter has an associated comment field to document the source of the value used.
These fields are not fully utilized in the example sets; but, as additional data are incorporated,
comments should be used liberally.
A study, with all associated data and output, can be archived in a study file. Good practice
dictates that the version of AQUATOX used for the application should be saved as well. In that way
the study can be opened and results examined at any time; and, if necessary, the model can be re-run.
The main screen indicates the dates and times that the perturbed and control simulations were run,
but be careful: opening some screens, such as Setup, will reset the status to "Run Not Current." If
you make a change to a study, you may choose not to save the changed file. To minimize file size,
do not save the output; this can be done by clicking on Study on the menu bar in the main screen
and choosing Clear Results. The file will usually be much smaller, but you will have to re-run the
simulation to see the results.
AQUATOX versions are upward compatible within reason—but not necessarily years
later—so if you open an old study with a newer version of the model, the data structure will be
updated. Usually this is automatic, but sometimes the user may be directed to assist in the upgrade,
as shown in the sequence of information windows below.
Information
to l
i^s«* ~ ^, ^* ~*—^'
-r, - »-^.,,"-L-
snould go into the Choirt, Underling Data and Re-Estimate K2s.
ire feihg converted to ararns>per square meter
' ~ '-'• • - * •*•
6-1
-------
-------
AQ\JATOXUSER'S MANUAL
REFERENCES
REFERENCES
Collins, Carol D., and Joseph H. Wlosinski, 1983. Coefficients for Use in the U.S. Army Corps
of Engineers Reservoir Model, CE-QUAL-R1. Vicksburg, Miss.: Environmental
Laboratory, U.S. Army Engineer Waterways Experiment Station, 120 pp.
Effler, Steven W. 1996. Limnological and Engineering Analysis of a Polluted Urban Lake.
New York: Springer-Verlag, 832 pp.
Hewett, Steven W., and Barry L. Johnson. 1992. Fish Bioenergetics Model 2. Madison, Wis.:
University of Wisconsin Sea Grant Institute, 79 pp.
McDonald, D.B. and M.P. McDonald. 1976. Coralville Water Quality Study Annual Report
Water Year October 1, 1974 to September 30, 1975. Report No. 187, Iowa Institute of
Hydraulic Research, The University of Iowa, Iowa City, Iowa, 78 pp.
Park, R.A. 1999a. Validation of the AQUATOX Model, Version 1.66 with Data from Coralville
Reservoir, Iowa. In: AQUATOX for Windows: A Modular Fate and Effects Model for
Aquatic Ecosystems-Volume 3: Model Validation Reports. U.S. Environmental
Protection Agency 2000. EPA-823-R-00-008.
Park, R.A. 1999b. Validation of the AQUATOX Model, Version 1.66, with Data from Lake
Onondaga, New York. In: AQUATOX for Windows: A Modular Fate and Effects Model
for Aquatic Ecosystems-Volume 3: Model Validation Reports. U.S. Environmental
Protection Agency 2000. EPA-823-R-00-008.
Redfield, A.C. 1958. The Biological Control of Chemical Factors in the Environment.
American Scientist 46:205-222.
R-l
-------
------- |