United States
Enivronmental Protection
Agency
Office of Research and
Development
Washington, DC 20460
EPA/600/R-00/060
September 2000
www.epa.gov/ncerqa
EPA Proceed i ngs
Coastal Intensive Sites Network
(CISNet): STAR Grants
2000 Progress Review
September 26-27, 2000
Narragansett, Rhode Island
NATIONAL CENTER FOR ENVIRONMENTAL RESEARCH
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Table of Contents
Introduction . . . ... v
Indicators of UV Exposure in Coral and Their Relevance to Global Climate
Change and Coral Bleaching .... . . . 1
Susan Anderson, Richard Zepp, Jana Machula, Debbie Santavy, Lara Hansen,
Gary Cherr, Erich Mueller (see also related work in Zepp et al.)
Factors Controlling UV Exposure of Coral Assemblages in the Florida Keys . . . . 3
Richard Zepp, Eric Davis, Susan Anderson, Jana Machula, Debbie Santavy, Lara Hansen,
Erich Mueller (see also related work in Anderson et al.)
An Autonomous, Moored Profiler: The Oceanic Remote Chemical/Optical Analyzer (ORCA) . ... 5
Steven R. Emerson, J.P. Dunne, A.H. Devol, M.J. Perry, J. Newton, R.A. Reynolds
Rhode River CISNet: Estuarine Optical Properties as an Integrative Response
to Natural and Anthropogenic Stressors ... . . 6
Charles L. Gallegos, Thomas E. Jordan, Patrick J. Neale
CISNet for the Neuse River Estuary, NC: A Program for Evaluating Nitrogen-Driven Eutrophication
Associated With Changing Land Use in a Coastal Watershed . . . . 7
Rick Luettich, Hans Paerl, Jay Pinckney
The Choptank River: A Mid-Chesapeake Bay Index Site for Evaluating
Ecosystem Nutrient Management ... 9
Thomas C. Malone, J. Court Stevenson, J. C. Comwell, L. W. Harding, W. C. Boicourt
CISNet: Molecular to Landscape-Scale Monitoring of Estuarine Eutrophication 10
James T. Morris, M. Fletcher, J. Jensen, A. Lewitus, P. Noble, D. Porter
CISNet San Pablo Bay Network of Environmental Stress Indicators ... . . 12
S. Geoffrey Schladow, T.M. Young, I. Werner, B. Thompson, J.A. Davis,
N. Nur, D. Schoellhamer
CISNet: Nutrient Inputs as a Stressor and Net Nutrient Flux as an Indicator of Stress Response
in Delaware's Inland Bays Ecosystem . . . . 13
William J. Ullman, Kuo-Chuin Wong, Joseph R. Scudlark, John M. Madsen,
David E. Krantz, A. Scott Andres, Thomas E. McKenna
Index of Authors . . . • 15
The Office of Research and Development's National Center for Environmental Research iii
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Introduction
In Fiscal Year 1998, the U.S. Environmental Protection Agency (EPA), in partnership with the National
Oceanic and Atmospheric Administration (NO A A) and the National Aeronautics and Space Administration (NASA),
funded a set of research grants to investigate monitoring approaches and ecological indicators for future use at U.S.
coastal monitoring sites. It is hoped that the research findings will be useful in the design of intensive, long-term
monitoring and research, particularly in estuarine and great lakes environments. A potential program to plan for such
sites, the Coastal Intensive Sites Network (CISNet), would be one possible application of the research, as would the
many regional and state coastal protection and monitoring programs currently underway throughout the country. As
a follow-on and expansion of this 1998 research program, EPA and NASA will be funding an additional set of larger,
longer term grants called the Estuarine and Great Lakes (EAGLE) projects, which will be selected and funded at the
end of 2000. Abstracts of the particular research to be funded under the EAGLE grants will be available on the EPA
Web Site in late 2000 or early 2001.
This volume, prepared in support of a program progress review meeting to be held in Narragansett, Rhode
Island, contains abstracts describing progress to date on the CISNet grants that were funded by EPA through its
Science to Achieve Results (STAR) research program. (STAR is EPA's principal program for providing extramural
grants to support environmental research). Abstracts of additional 1998 CISNet projects funded by NOAA and NASA
will be available in a future progress review volume, when all of the grants near completion.
CISNet has three general objectives:
(1) To develop a scientific basis for understanding ecological responses to anthropogenic stresses in coastal
environments, including the interactions of exposure, environment/climate, and ecological factors, and the
spatial and temporal nature of these interactions.
(2) To demonstrate the usefulness of intensively monitored sites for examining short-term variability and long-
term trends in the relationships between natural and anthropogenic stressors and ecological responses.
(3) To evaluate indicators of change hi coastal systems at particular intensively monitored sites.
If you have any questions regarding EPA's CISNet grants, you can contact the program manager, Kim
Devonald, at 202-564-5178, or by e-mail at devonald.kim@epa.gov. (For information about the future EAGLE
program, contact the program manager, Barbara Levinson, at 202-564-6911.)
The Office of Research and Development's National Center for Environmental Research
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Indicators of UV Exposure in Coral and Their
Relevance to Global Climate Change and Coral Bleaching
Susan Anderson \ Richard Zepp2, Jana Machula', Debbie Santavy3, Lara Hansen3, Gary Chen1,
and Erich Mueller4
'University of California-Davis, Bodega Marine Laboratory, Bodega Bay, CA; 2USEPA NERL, Athens, GA;
3USEPA NHEERL Gulf Breeze, FL; 4Mote Marine Laboratory Summerland Key Facility, Summerland Key, FL
The frequency and severity of coral bleaching has
increased dramatically over the last 2 decades, posing a
serious threat to coral resources worldwide. Bleaching
can destroy large areas of a reef with limited recovery or
recruitment, and it may be induced by a variety of
stressors. Increased temperature is implicated in most
bleaching events, but a possible synergy between temper-
ature and ultraviolet light has been proposed.
Under conditions of ocean warming, often asso-
ciated with calm, stratified waters, photobleaching of
UV-absorbing chromophoric dissolved organic matter
(CDOM) is increased, and penetrance of both UV-B and
UV-A is greatly enhanced. Indices of UV-specific ef-
fects in coral tissue are needed to test whether increases
in UV, associated with global climate change, are harm-
ful to coral. To address this challenge, UV-specific ef-
fects in coral have been evaluated, and factors that alter
penetrance of UV radiation over coral reefs have been
characterized.
An immunoblotting assay was developed to exam-
ine UV-specific lesions (thymine dimers) in coral and
zooxanthellae DNA. Dose-dependent increases of thy-
mine dimers were observed in purified coral (Porites
porites) DNA exposed to UV-C in the laboratory and
with intact P. porites in a Suntest solar simulator. How-
ever, with whole coral, effects were not strictly propor-
tional at the lowest exposure times (see Figure 1). Next,
the assay was used to determine whether thymine dimers
are detected under realistic field conditions (Maryland
Shoals, Florida Keys, July 1999). Thymine dimers in P.
porites collected at 0830 hrs and at 1300 hrs differed
significantly (p = 0.04). A diurnal variation experiment
was conducted in July 1999 at Eastern Sambo Reef (Flo-
rida Keys), and samples currently are being analyzed.
Sampling was conducted at multiple timepoints to deter-
mine whether thymine dimers follow hypothesized di-
urnal cycles. Chlorophyll, tissue protein, zooxanthellae
counts, and carotenoid pigments also will be analyzed.
Immunofluorescence techniques are now being de-
veloped that will help determine where dimers are lo-
calized within coral tissue and zooxanthellae. Results
obtained to date indicate that UV-specific effects can be
discerned under field conditions and related to exposure
dose. Studies now underway will help determine wheth-
er these effects are linked to coral bleaching and to other
indicators of stress in coral. UV measurements also
were made as part of the experiments conducted during
July 1999 at Eastern Sambo reef and nearby sites in-
cluding profiling along transects from reef to shore.
These findings represent the first known attempt to
evaluate UV-specific DNA damage in coral, and together
with the dosimetry data, they represent an important first
step in assessing the role that UV radiation may play in
coral bleaching. The next steps will be to: (1) complete
development of the thymine dimer assay, (2) complete
work underway to localize dimers in coral and zoo-
xanthellae, and (3) evaluate interactions between temper-
ature and UV light.
The Office of Research and Development's National Center for Environmental Research
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Induction of Thymine Dimers in P. porites Using a Solar Simulator
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Figure I. Coral pieces were collected from natural reefs in the Florida Keys and held in a UV-free environment prior to exposure in a solar
simulator. Thymine dimers are represented as relative pixel intensity in 1.0 mg of DNA, and vary significantly in each treatment
(Kruskal-Wallis P=0.01). Error bars represent standard deviation.
The Office of Research and Development's National Center for Environmental Research
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Factors Controlling UV Exposure
of Coral Assemblages in the Florida Keys
RichardZepp1, Eric Davis1, Susan Anderson2, Jana Machula2, Debbie Santavy3, Lara Hansen3,
and Erich Mueller4
'USEPA NERL, Athens, GA; 2University of California-Davis, Bodega Marine Laboratory, Bodega Bay, CA;
3USEPA NHEERL Gulf Breeze, FL; "Mote Marine Laboratory Summerland Key Facility, Summerland Key, FL
Recent studies have indicated that solar UV radi-
ation is a significant stressor of coral assemblages in
tropical and subtropical marine environments. Al-
though increased exposure to UV has been tightly
linked to stratospheric ozone depletion, there is evi-
dence that UV exposure of corals also is strongly af-
fected by changes in UV-absorbing substances in the
overlying water. In particular, these results indicate
that changes in chromophoric dissolved organic matter
(CDOM) play a critically important role in controlling
underwater UV exposure in the Florida Keys.
To define factors that affect UV exposure, depth
profiles of underwater UV and visible irradiance were
measured at a number of sites on cruises aboard the
OSV P.W. Anderson during 1998 and 1999 and, as
part of the experiments conducted during July 1999, at
Eastern Sambo reef and nearby sites along transects
from reef to shore. Water samples were obtained at
these sites, and absorption and fluorescence spectra
and chemical properties of the filtered water samples
were obtained.
Using these irradiance and spectral data and the
Setlow action spectrum for DNA damage, dose rates
of DNA-damaging UV for various depths at Eastern
Sambo and nearby sites were computed. Results of
these analyses indicate that the coral reefs at Eastern
Sambo were receiving considerable exposure to DNA-
damaging radiation during July that was approximately
10-35 percent of surface UV irradiance at a depth of
3-4 meters (see Figure 1).
Water just inside the reef in Hawk Channel and
water closer to land was considerably more opaque to
UV due to higher concentrations of CDOM derived
from long-range transport of CDOM from Florida Bay
and the Everglades, from onshore mangroves, and
from sea grasses in the channel. Water from Hawk
Channel photobleached with loss of UV absorbance
when it was exposed to simulated solar radiation.
These findings suggest that several interacting
climatic and other factors are affecting UV exposure in
the Florida Keys. Large-scale hydrologic manipula-
tions of the Everglades, coupled with changes in pre-
cipitation patterns and runoff, likely have altered the
amounts and variability of UV-protective CDOM in
Hawk Channel and out over the coral reefs. Increased
UV-B radiation at the surface of the water due to
stratospheric ozone depletion can enhance photo-
bleaching of the CDOM. This photobleaching effect,
moreover, interacts with climate related factors such
as warming-induced stratification or transport from
CDOM-rich waters such as Hawk Channel, Florida
Bay, and the Everglades.
To build on the initial results of this project, it is
planned to: (1) more carefully examine the effects of
water stratification and photobleaching on UV expo-
sure at the corals sites; (2) compare spectral and other
properties of the CDOM along transects in Hawk
Channel and at coral reef sites to identify the major
sources of CDOM; (3) conduct manipulations to
identify factors that affect the photobleaching; (4) ob-
tain continuous data on CDOM concentrations at Flor-
ida Keys sites such as Sand Key site based on fluor-
escence measurements; and (5) help develop methods
and action spectra to relate these observations to
changes in UV-specific damage to the coral and zoo-
xanthellae DNA.
The Office of Research and Development's National Center for Environmental Research
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1e-5
Surface
Eastern Sambo, z = 4.0 m
Mid-Hawk Channel, z = 4.0 m
dose rate = 6.15 x 1CT6 W crrf2
dose rate = 2.21 x 10~5 W cm"2
dose rate= 1.78x 10'' Wcm
280
300 320 340
Wavelength, nm
360
Figure 1. DNA-damaging weighted irradiance estimated for near the surface and at depth of 4.0 meters for Eastern Sambo and mid-Hawk
Channel sites located in the Florida Keys.
The Office of Research and Development's National Center for Environmental Research
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An Autonomous, Moored Profiler: The
Oceanic Remote Chemical/Optical Analyzer (ORCA)
Steven R. Emerson, J.P. Dunne, A.H. Devol, M.J. Perry, J. Newton, and R.A. Reynolds
School of Oceanography, University of Washington, Seattle, WA
The purpose of this project is to establish a long-
term water quality monitoring site in South Puget Sound.
This system of fjords is fed by high-nutrient, oxygen-
poor waters from the northeast Pacific. Although the
main basin of Puget Sound is tidally mixed, parts of
South Puget Sound are seasonally stratified and nutrient
limited. The area currently is predominantly undevel-
oped, but it is expected to undergo extensive urbanization
in the coming years. Because the area already is sen-
sitive to oxygen depletion, eutrophication derived from
long-term urbanization is of great water quality concern.
To monitor water quality in the area, the Wash-
ington State Puget Sound Ambient Monitoring Program
(PSAMP) currently conducts monthly sampling at a suite
of sites in Puget Sound via seaplane. The sampling,
however, is coarse both temporally and vertically, mak-
ing it difficult to distinguish local, tidal, diurnal, sea-
sonal, and long-term effects.
For this research project, an autonomous, moored
profiler called the Oceanic Remote Chemical/Optical
Analyzer (ORCA) (see Figure 1) was developed to sense
a variety of physical, chemical, and optical properties at
high temporal and vertical resolution. This is an inten-
sive effort to complement the extensive PSAMP one
program. ORCA has three main components: (1) a
three-point moored ATLAS toroidal float; (2) a profiling
assembly on the float with a Tattletale-8 microcomputer,
marine winch with slip rings, cellular system for remote
programming and data download, batteries, and solar
panels for battery recharge; and (3) an underwater sensor
package at the end of a hydro-wire with Seabird CTD
profiler, YSI dissolved oxygen electrode, Wetlabs trans-
missometer for particle concentration, and Wetlabs chlo-
rophyll fluorometer for phytoplankton concentration.
At regular sampling intervals, ORCA's winch pro-
files the sensor package through the water column using
pressure data from the CTD. ORCA has undergone ex-
tensive tests and was moored in Carr Inlet, South Puget
Sound on May 26, 2000. Since that time, it has been
gathering water quality data, detailing extensive strati-
fication, oxygen depletion, and phytoplankton biomass
variability in the area. These results will be compared
with data collected aboard ship and during the PSAMP
flights.
The next step is to add a suite of additional sensors:
meteorological sensors (wind, temperature, humidity, ir-
radiance), a Moss Landing Marine Labs chemical nitrate
analyzer, a Pro-Oceanus chemical dissolved oxygen sen-
sor, a Pro-Oceanus total dissolved gas sensor, an under-
water photosynthetically active radiation (PAR) sensor,
and an instrument for measuring spectral absorption and
scattering coefficients (Wetlabs AC-9).
Figure 1. The Oceanic Remote Chemical/Optical Analyzer (ORCA).
The Office of Research and Development's National Center for Environmental Research
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Rhode River CISNet: Estuarine Optical Properties
as an Integrative Response to Natural and Anthropogenic Stressors
Charles L. Gallegos, Thomas E. Jordan, and Patrick J. Neale
Smithsonian Environmental Research Center, Edgewater, MD
Light penetration in estuaries is governed by three
factors that are broadly indicative of the health of the
system and that are impacted by different human activ-
ities. Those factors are phytoplankton chlorophyll, an
indicator of eutrophication caused by nutrient over-
enrichment; suspended sediment, resulting from soil ero-
sion and resuspension of bottom sediments; and dissolved
color, which comes from decaying plant matter or cer-
tain industrial (e.g., paper mill) effluents.
The primary objective of this work is to utilize
recent advances in monitoring of estuarine spectral opti-
cal properties to develop the capability to continuously
monitor concentrations of factors that affect light pene-
tration in the water. Synthesis of results will be aimed
at developing estuarine optical properties as an integrated
measure of response to perturbations on time scales rang-
ing from individual storms or phytoplankton blooms, to
seasonal, decadal, or longer responses to increased dis-
turbance or to management efforts.
A system for continuously monitoring spectral ab-
sorption and scattering coefficients that utilizes a com-
mercially available absorption/transmittance meter has
been developed. Research is being conducted to inter-
pret continuously monitored optical properties in terms
of the three factors that govern light penetration. Ad-
ditionally, manipulative experiments are being conducted
to establish the response of in situ concentrations of
chlorophyll, suspended sediments, and dissolved color to
inputs of nutrients on event to interannual time scales.
Finally, process level research is being conducted to
examine the effects of solar UV radiation on nearshore
plankton communities, as influenced by potential changes
in estuarine optical properties.
A self-cleaning flow-through system has been de-
signed to supply water to the optical monitoring instru-
ment at hourly intervals. Monitoring data collected to
date indicate that the system will be useful for resolving
changes in phytoplankton chlorophyll over a wide range
of time scales. Manual sampling over a 24-hour period
in conjunction with the automated monitoring has ver-
ified that the system is measuring actual changes in
optical properties. A mathematical procedure for deter-
mining the concentrations of light-absorbing materials
has been developed, and shows great promise for inter-
preting the monitored data.
The system was in place during a major algal
bloom in upper Chesapeake Bay in the spring of 2000.
This red tide was widely publicized in the local media.
The measurements obtained in this work will provide a
quantitative estimation of the impact of this and similar
events on light availability for submerged bay grasses
during a critical period in their growth season.
In the coming year, data on the World Wide Web
will begin to be posted. Creation of an FTP site that will
be linked to the main research page of our local Web Site
(www.serc.si.edu) is underway. Measurements of pro-
cesses that result in nutrient inputs and eutrophication in
the system will continue during the coming year. In ad-
dition, it is planned to construct a mobile unit for mea-
surement of spatial variability in optical properties, to
extend the measurements to other tributaries as well as
the mainstem of Chesapeake Bay.
»---•*
Figure 1. Technicians measuring underwater light spectra and light attenuation at the Rhode River CISNet Site.
The Office of Research and Development's National Center for Environmental Research
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CISNet for the Neuse River Estuary, NC:
A Program for Evaluating Nitrogen-Driven Eutrophication
Associated With Changing Land Use in a Coastal Watershed
Rick Luettich, Hans Paerl, and Jay Pinckney
University of North Carolia Institute of Marine Sciences, Morehead City, NC
Over the past 2 decades, the Neuse River Estuary
(NRE) has been plagued with nuisance algal blooms,
hypoxia, toxicity, and fish kills associated with declining
water quality. Increased nitrogen (N) loading associated
with human population growth and land-use changes has
been implicated. In response to mounting scientific evi-
dence and public pressure, the State of North Carolina
has legislated that a 30 percent reduction in external N
loading (based on a mean 1990-1995 N loading "cap")
be in place in the NRE by 2003. This represents a large-
scale experiment that provides a unique opportunity to
examine the effects of nutrient reduction on the eco-
system.
The objective of this CISNet program is to examine
the impacts of external stressors—most prominently N
loading—on the health of the NRE ecosystem. This re-
quires development of time series of loading, transport,
and spatially explicit indicator responses capable of sepa-
rating long-term trends from interannual variability. The
approach includes ongoing field-based studies of: (1) hy-
drography, nutrients, DO, light, and phytoplankton dy-
namics; (2) atmospheric N inputs; and (3) circulation in
the NRE-Pamlico Sound system.
The focus has been on dissolved oxygen and the
planktonic microalgal community, as they are easy-to-
measure indicators of the biotic response of this ecosys-
tem to external stressors. Dissolved oxygen depletion re-
stricts benthic habitat and plays a causal role in fish kills.
Phytoplankton dominate primary production and nutrient
fluxes (e.g., in the Neuse-Pamlico Sound system, about
80 percent of the annual "new" C input is attributable to
phytoplankton). A natural attribute of the phytoplankton,
photopigments (determined by high-performance liquid
chromatography [HPLC] coupled to spectrophotometry),
are being used to rapidly and effectively distinguish
major phytoplankton functional groups, including poten-
tially harmful dinoflagellates and blue-green algae (cya-
nobacteria).
N loading over the past year was dominated by the
extreme (~ 500 year) runoff event associated with Hur-
ricane Floyd. The NRE responded to the organic and in-
organic nutrient loading associated with this event with
extensive bottom-water hypoxia that lasted several weeks
and the development of an algal bloom (chlorophyll-a
levels above 20 (J.g/1, compared with typical values of
approximately 3-6 [J.g/1) at the mouth of the NRE (see
Figure 1). This bloom has persisted into spring 2000
(i.e., 7 months), indicating a possible longer term (at
least multiseasonal) trophic shift of the system in
response to the hurricane's floodwaters. Diagnostic pig-
ment analyses are being used to examine shifts in bloom
composition and dynamics during this large-scale event.
Ecosystems such as the NRE may be expected to
respond very differently to long-term, chronic nutrient
stress and short-term, intense, episodic nutrient stress.
The funding provided by CISNet is allowing for the
expansion of earlier observational programs in the NRE
to develop timeseries that are capable of separating long-
term trends from high interannual variability. At the
same time, this funding has allowed for the unprece-
dented opportunity to observe the ecological conse-
quences of an extreme event in the NRE. Understanding
the relative roles of chronic and event-based stressors is
critical if a determination is to be made of the effec-
tiveness of nutrient reduction in systems such as the NRE
given the forecast of enhanced hurricane activity during
the next 20 years.
Activities in 2000-2001 will include: (1) continu-
ation of the ongoing field program, (2) expansion of the
photopigment techniques as part of a continuous water
quality monitoring program utilizing the NC Ferry sys-
tem as "ships of opportunity" for sampling the Neuse
River Estuary and Pamlico Sound, and (3) exploring eco-
system-scale quantification of photopigments (phyto-
plankton biomass) by remote sensing (aircraft and satel-
lite) with Dr. L. Harding (University of Maryland).
The Office of Research and Development's National Center for Environmental Research
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Figure 1. Response near the mouth of the Neuse River Estuary to Hurricane Floyd, which struck during September 15-16, 1999.
The Office of Research and Development's National Center for Environmental Research
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The Choptank River: A Mid-Chesapeake Bay
Index Site for Evaluating Ecosystem Nutrient Management
Thomas C. Malone, J. Court Stevenson, J.C. Cornwell, L.W. Harding, and W.C. Boicourt
University of Maryland Center for Environmental Science (UMCES), Horn Point Laboratory, Cambridge, MD
The Choptank River has been largely impacted in
the past by agricultural activities on the Delmarva Pen-
ninsula, especially over the last 50 to 100 years as fer-
tilizer usage steadily increased until the 1980s, when
efforts began to curtail nutrient inputs. This project fo-
cuses on monitoring via traditional shipboard sampling
and retrospective data analysis as well as remote sensing
approaches to determine estuarine responses to changing
management strategies.
Water quality sampling in this project began in
January 1999, in a particularly dry year, and is contin-
uing under much wetter conditions in 2000. The data
suggest that nutrient loadings were reduced in 1999,
which undoubtedly was a factor in increasing the abun-
dance of submersed aquatic vegetation in the shallows
downstream. However, after the drought ended in
spring, there were large dinoflagellate blooms (Prorocen-
trum sp.), in several locations reflecting a flush of nutri-
ents had occurred in the Choptank watershed. In addi-
tion, the Choptank bifurcates with the main arm having
more wetland buffering from the other more agricul-
turally dominated Tuckahoe. The Tuckahoe has been un-
derstudied historically, but appears to have much differ-
ent nutrient dynamics. It has particularly high nitrate
loadings, reflecting the large agricultural inputs in this
area.
The measurement of denitrification and calculations
suggest that if well positioned in the landscape, tidal wet-
lands may be able to buffer as much as 80 percent of the
incoming nitrate in groundwater and are a significant
term in the budget in the mainstem of the Choptank.
Thus, fringe marshes are very effective in reducing ni-
trogen loadings. Unfortunately, these are beginning to
decrease in effectiveness because of high rates of sea
level rise in this system, particularly over the last decade
when rates have averaged 1.3 cm/yr.
It may not be surprising in view of this diminished
function that the Choptank has shown slightly increasing
nutrient concentrations over the last 20 years (despite
massive attempts to clean up the Chesapeake). This is
attributable to the fact that little has been done to actually
reduce nitrogen and phosphorus loadings on the Eastern
Shore of the Bay—other than creating grass buffer strips.
More recently, winter cover crops have shown promise,
and these are being used in increasing percentages in re-
cent years to remove excess nitrogen fertilizers in the
fall.
Another pervasive problem is the nitrogen and
phosphorus in sewage sludge from the western shore
wastewater plants, which may eventually be transported
to tributaries such as the Choptank.
Current efforts are focused on trying to target "hot-
spot areas" in this tributary using a combination of older
photographic as well as new techniques, such as hyper-
spectral analysis, to help guide increased efforts to con-
trol diffuse source pollution.
The Office of Research and Development's National Center for Environmental Research
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CISNet: Molecular to Landscape-Scale
Monitoring of Estuarine Eutrophication
James T. Morris, M. Fletcher, 3. Jensen, A. Lewitus, P. Noble, and D. Porter
Belle W. Baruch Institute for Marine Biology and Coastal Research, University of South Carolina, Columbia, SC
This research project addresses three major hypoth-
eses : (1) the composition and abundance of bacterial and
phytoplankton communities will differ among estuaries
as functions of nutrient availability; (2) bacterial and
phytoplankton communities form associations that vary
in complexity (species diversity) as a function of nutrient
availability; and (3) at a landscape-scale, remote sensing
of the concentration of chlorophyll in emergent wetland
vegetation will provide a quantitative index of wetland
condition and will demonstrate differences in nutrient
loading among estuaries.
This work is focused on two South Carolina estu-
aries that have different nutrient loadings. Preliminary
findings from the phytoplankton component of this re-
search indicates that there are significant differences in
phytoplankton communities between sites, and that these
communities can be distinguished by using high-perfor-
mance liquid chromatography (HPLC) to analyze the
photopigments in water samples.
These observations indicate that diatoms generally
respond favorably to high nutrient (especially NO3) in-
puts, while marine cyanobacteria are adapted to oligotro-
phic conditions. It is envisioned that the combined ap-
plications of CHEMTAX and neural computing to HPLC
pigment profiles will lead to a major advance in the cur-
rent capabilities in determining phytoplankton community
composition.
Using neural network (NN) sensitivity analysis, it
was found that salinity, DOC, temperature, NH4, sample
position in the water column, and orthophosphate (OP)
had significant associations with the pigments. The pig-
ment violaxanthin, an accessory pigment of green algae,
had strong, positive associations with NH4 and ortho-
phosphate. Developing NNs that can recognize the as-
sociation between HPLC pigment profiles and phyto-
plankton taxonomy will allow for the forecasting of envi-
ronmental conditions that promote different community
types, including red tide blooms. Work on the bacterial
communities using DGGE is progressing, and results
from DGGE analysis indicate significant community dif-
ferences within and between the two sites.
A second component of this project is developing
linkages between remotely sensed images of coastal wet-
lands, fertility or nutrient status, and the chlorophyll den-
sity of the emergent wetland plant community. In situ
biophysical (chlorophyll, biomass) data obtained at ap-
proximately 50 locations within each of the Spartina
altemiflora-dominated study areas are being used to de-
velop regression models between ecological variables and
remote sensor data.
These models will be used to produce "greenness"
maps depicting the functional health and productivity of
the estuarine wetland vegetation. Maps of functional
ecosystem health for each year of the study and a change
detection analysis between 1999 and 2001 will be devel-
oped using this technique. This will provide baseline
data for long-term monitoring of coastal estuarine wet-
lands, and the techniques being developed should be ap-
plicable to other coastal regions.
To develop tools for interpreting remotely sensed
data, the light energy reflected from individual plant
leaves is being examined with a spectroradiometer,
which is providing information about the quality of light
reflected from the plant canopy (see Figure 1), and is
being correlated with related biophysical data, such as
leaf area index (LAI), tissue nitrogen concentration,
chlorophyll, and CO2 exchange rates. These results
should allow for a determination of which wavelengths
are most sensitive to environmental variables such as
nutrient availability. Then, it should be possible to de-
velop models that can be used to interpret remotely
sensed data such as multispectral ADAR images.
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1-0 1
Mean reflectance from Spartina
leave© from two sites in the
ACE Basin Estuary, SC, May 2000
800
300 400 500 600
Wavelength
700
800
Figure 1. Examples of mean reflectance of light from Spartina leaves collected from two sites within the ACE Basin Estuary, SC. St.
Pierre is a site that is impacted by a nearby marina and housing. Big Bay is not impacted. The top figure shows reflectance as a
function of wavelength. In the bottom figure, reflectance has been standardized to the peak chlorophyll-a reflectance at 430 nm.
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CISNet San Pablo Bay Network of Environmental Stress Indicators
S.Geoffrey Schladow1, T.M. Young1, I. Werner2, B. Thompson3, J.A. Davis3, N. Nur4, and
D. Schoellhamer5
'Department of Civil and Environmental Engineering, University of California, Davis, CA; Departments of
Anatomy, Physiology, and Cell Biology, University of California, Davis, CA; 3San Francisco Estuary Institute,
Richmond, CA; "Point Reyes Bird Observatory, Stinson Beach, CA; 5U.S. Geological Survey, Sacramento, CA
The primary objective of this research project is to
design an estuarine and wetland monitoring network that
is temporally and spatially adequate to indicate ecological
impacts of natural and anthropogenic stressors. Specific
goals include: (1) determining spatial and temporal var-
iability in anthropogenic and natural stressors; (2) de-
veloping and testing indicators of ecological health and
understanding their natural variability; (3) identifying
relations among indicators to refine their deployment;
and (4) developing and demonstrating the monitoring
network.
Flow, conductivity, temperature, depth, and optical
backscatter are measured continuously for two 3-month
periods during summer and winter at six sites. At 12
sites, water column and sediments are sampled monthly
and analyzed for a suite of trace metal and organic
compounds. Supercritical fluid extractability and aque-
ous desorption potential will be used to predict local
contaminant effects on benthic organisms. Relationships
between sediment-borne and water-borne contaminant
fluxes and toxicity will be investigated using correlation
analysis, principal components analysis, and multiple
regression to identify statistical associations.
Biochemical indicators of ecological stress will be
investigated in Macoma balthica and Ampelisca abdita.
Monitoring sensitive biochemical and cellular indicators
of deleterious effects should foretell subtle and possibly
longer term consequences of exposure to chemicals in the
environment. Sublethal effects will be compared to con-
taminant body burden and higher level effects such as
growth and mortality. Ecological stress indicators in-
clude benthic community composition, contaminant bio-
accumulation in fish tissue, and bioaccumulation and
reproductive success for two bird species: Double-
Crested Cormorants and Song Sparrows.
Methods for interpreting indicator outcomes will be
facilitated by knowledge gained from the research on
processes and mechanisms of flow and sediment trans-
port, as well as relationships among indicators. Demon-
stration monitoring of these sites and the selected in-
dicators will be performed at the end of Year 2 and early
in Year 3, hi coordination with the San Francisco Bay
Regional Monitoring Program for Trace Substances
(RMP). Flux data still are being analyzed; however, an
interesting phenomena showed tidally averaged water and
suspended-solids fluxes (SSF) can occur in opposite
directions. This demonstrates that both water and SS
fluxes are necessary to determine the fate and transport
of dissolved and adsorbed contaminants. Desorption rate
measurements are being conducted by combining con-
taminated sediment with clean background water and
a sorbent resin (Tenax beads) in a vial that is contin-
uously mixed. The resin beads serve as an infinite sink
for hydrophobic organic contaminants, keeping aqueous
concentrations always close to zero.
Cadmium and the insecticide esfenvalerate were
chosen as model pollutants for laboratory studies. In ad-
dition, the effects of natural stressors (salinity and tem-
perature variations) were investigated. A. abdita sur-
vival after 4 days of exposure was equal to controls in all
Cd treatments, whereas all animals died when exposed to
0.1 and 0.5 (-ig/L esfenvalerate (nom. cone.). As this
compound is hydrophobic, actual concentrations in these
treatments are likely to be lower. Esfenvalerate is ex-
tremely toxic to A. abdita. Exposure to esfenvalerate did
not affect survival of M. balthica. Tissue concentrations
and bioaccumulation potential are being determined.
Fish are being sampled in three habitat types: open
bay, tidal marsh, and freshwater creek. The two species
sampled in 1999 were Staghorn Sculpin and Striped
Bass. Both species are resident in the San Pablo Bay
ecosystem and are predators that are exposed to
relatively high concentrations of toxicants due to their
trophic position. Contaminants being measured include
mercury, selenium, PCBs and other trace elements, and
organochlorine pesticides. Chemical analysis of the fish
collected in 1999 currently is in progress.
Study plots were established for Song Sparrow
breeding at four sites in three San Pablo Bay marshes.
Nests also were monitored at two Suisun Bay tidal mar-
shes and at the upland Palomarin field station. Cormor-
ant eggs were collected from a colony on the Richmond
Bridge. Chemical analysis of these samples is in pro-
gress. In samples from 1999, mercury concentration in
fail-to-hatch Cormorant eggs were higher than in ran-
domly collected eggs. For the Song Sparrows, prelim-
inary analysis indicates that there is no significant differ-
ence among the sites in San Pablo Bay hi terms of egg
hatchability, nor a significant difference in hatchability
between San Pablo Bay and the Suisun sites.
The main significance of the results to date is that
they generally confirm the suitability of the approach
selected. Many of the chemical analyses have yet to be
completed, so spatial and temporal trends cannot be
ascertained at present. The next major instrument de-
ployment is being prepared, and Year 2 sampling of fish
and birds also is underway. Later this year, the first
demonstration monitoring exercise by the RMP will take
place. A recent toxicity event within the boundaries of
the study area is a major focus. It is planned to ac-
celerate the analysis of some archived samples and to
take additional samples in the vicinity of the event.
12
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CISNet: Nutrient Inputs as a Stressor and Net Nutrient Flux
as an Indicator of Stress Response in Delaware's Inland Bays Ecosystem
William J. Ullman1'2, Kuo-Chuin Wong1, Joseph R. Scudlark1, John M. Madsen2'2, David E. Krantz4'1,
A. Scott Andres3, and Thomas E. McKenna3
1 College of Marine Studies, Department of Geology, and3Delaware Geological Survey, University of Delaware,
Lewes, DE and Newark, DE; 4U.S. Geological Survey, Dover, DE
This program is focused on the watershed of
Delaware's Inland Bays, members of a common but
understudied class of shallow estuarine ecosystems. The
objective of this program is to document the sources and
sinks of nutrients (nitrogen, phosphorus, and organic
carbon) to and from the Bays. This watershed receives
excessive nutrient fluxes from agricultural, municipal,
domestic, and industrial sources. These lead to a number
of undesirable consequences of eutrophication in the
Bays. Nuisance algal blooms and episodes of anoxia are
common in the Inland Bays.
The specific goals of this study are to: (1) deter-
mine the sources, magnitudes, and spatial and temporal
variability of nutrient fluxes to the Bays; (2) assess the
magnitude of nutrient sinks in this system; and (3) de-
velop conceptual and simple quantitative models that re-
late these inputs and outputs to more easily measured and
monitored hydrological forcing parameters such as pre-
cipitation, temperature, season, groundwater levels, and
surface-water discharge.
The research is divided into six subprograms.
These include components dealing with inputs from tri-
butary streams, groundwater, and atmospheric deposi-
tion; inputs and outputs from the coastal ocean; outputs
to sediments; and nutrient processing within the Bays.
Progress has been made on all components of this effort,
except for the outputs to sediments component, which is
scheduled for 2001.
Baseflow discharges of nutrients from 14 tributary
streams to the Bays continue to be sampled biweekly
throughout the year. Tributaries were chosen on the ba-
sis of land use/land cover of their subwatershed and the
significance of the total discharge. At six of these sites,
stormwater discharges also have been sampled with fun-
ding from the Delaware Department of Natural Re-
sources and Environmental Control. Precipitation chem-
istry is monitored on an ongoing basis at Cape Henlopen
State Park, under the auspices of the NOAA-AIRMoN
Program to determine the direct input of atmospheric ni-
trogen to the Inland Bays ecosystem. A second monitor-
ing site, closer to the Bays, also has been established for
this project.
An aerial thermal radiometer survey of the Bays
was conducted in early 1999 to detect intense localized
groundwater discharges. Sites identified by this survey
have been visited to determine whether the observed
thermal anomalies are associated with fresh groundwater
seepage or other processes. Surveys of water and salt
fluxes between Indian River Bay and the adjacent coastal
waters and at other major channels within the ecosystem
were conducted. Surface water samples are collected
monthly during the spring, summer, and fall for the de-
termination of changing nutrient distributions within the
Bays.
In some tributaries, the concentrations of dissolved
nutrients in baseflow appear to vary little; therefore, the
net flux from these tributaries appears to be primarily
dependent on the rate of water discharge. In other
streams, the concentrations of nutrients appear to vary
inversely with discharge. The atmospheric deposition of
nitrogen provides between 14 and 24 percent of the total
annual input to the Bays. Nitrogen deposition from the
atmosphere is substantially higher in summer than win-
ter. A number of sites have been identified for further
detailed study of groundwater fluxes. One such site cur-
rently is being instrumented to document the spatial and
temporal variability of discharge and the subsurface
geology controlling the discharge. Tidal currents are
dominated by the semidiurnal tides. Weaker semidiurnal
tides produce significant modulations in the tidal
currents.
Land use/land cover appears to control the char-
acter of nutrient fluxes from tributaries. It is not ap-
propriate to use discharge alone as an indicator of the
seasonal variability of nutrient fluxes from the watershed
to the Bays. Atmospheric inputs of nitrogen during the
summer may be ecologically extremely important, as
surface waters in large areas of the Bays are N-limited
during this period. The local contributions of nitrogen to
the atmospheric budget are comparable in magnitude to
all of the other sources. The data collected during Hur-
ricane Floyd (September 1999) will allow for an examin-
ation of the impact of extreme hydrological events on
nutrient flushing of the Inland Bays.
The bulk of the present research activity is con-
cerned with the analysis of the baseflow and storm dis-
charge results and putting this data into an easily ac-
cessible database management system (using Microsoft
Access) to allow access by all of the CISNet collab-
orators and collaborators from state and federal agencies.
Analysis of water, salt, and nutrient exchange continues,
and analysis of the distributions of nutrients in the
surface waters of the Bays is beginning. Preliminary
geophysical surveys in support of the proposed sediment
sampling are being conducted this year.
Additional assistance in meeting the goals of this
program has been provided by the U.S. Geological
Survey, the Delaware Geological Survey, the Delaware
Sea Grant College Program, and the Delaware Center
for the Inland Bays.
The Office of Research and Development's National Center for Environmental Research
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Index of Authors
Anderson, S., 1
Emerson, S.R., 5
Gallegos, C.L., 6
Luettich, R., 7
Malone, T.C., 9
Morris, J.T., 10
Schladow, S.G., 12
Ullman, W.J., 13
Zepp, R.,3
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