Grantee Research Project Results
2000 Progress Report: Health Indicators for Salt Marsh Estuaries of the South Atlantic Bight
EPA Grant Number: R825147Title: Health Indicators for Salt Marsh Estuaries of the South Atlantic Bight
Investigators: Alberts, James J. , Kneib, Ronald T. , Newell, Steven Y. , Pennings, Steven
Institution: University of Georgia
EPA Project Officer: Packard, Benjamin H
Project Period: October 1, 1996 through September 30, 1999
Project Period Covered by this Report: October 1, 1999 through September 30, 2000
Project Amount: $786,349
RFA: Ecological Assessment (1996) RFA Text | Recipients Lists
Research Category: Ecological Indicators/Assessment/Restoration , Aquatic Ecosystems
Objective:
The research examines development and testing of simple, inexpensive, and rapid methods for assaying and monitoring the general health of salt marsh ecosystems in the southeastern United States. It is designed to examine a suite of salt marsh indigenous organisms to:
- Evaluate methods that determine critical rates within the macrophyte community, focusing on sublethal impacts;
- Determine the efficacy of using reproductive potential of three species of estuarine crustaceans as another measure of sublethal stress; and
- Evaluate a battery of physiological bioassays using short lived marine
microorganisms as indicators of salt marsh ecosystem condition.
Progress Summary:
Microtox? Laboratory and Field Studies (Alberts). All field and laboratory studies were concluded during Year 3. This year was spent in finishing data analyses and preparing presentations and manuscripts. During the year, three presentations were made at national and international meetings in Boston, MA, Washington, DC, and Karlsruhe, Germany, one paper was published and another is in press (see Publications/Presentations).
Fungal Subproject (Newell). This was a year of winding down of sampling. Efforts were concentrated upon processing of samples and publication and presentation of findings, with one invited presentation in Canada, two published papers and four additional manuscripts in press (see Publications/Presentations). It is hoped that the central finding of the fungal subproject, that saltmarsh ascomycetes are very resistant to toxic pollutants, will lead to studies of these ascomycetes to determine their potential for bioremediation of contaminated saltmarsh and other coastal-marine areas.
Macrophyte Subproject (Pennings). Work in Year 4 has focused on data analysis and manuscript preparation, which has resulted in two papers in press and four additional manuscripts in preparation (see Publications and Presentations). Our field studies at heavily polluted sites in Brunswick, GA (a Superfund site polluted with mercury and PCBs, and a site polluted with toxaphene), and Charleston Harbor, SC (several sites polluted with metals and PAHs) have generally revealed little impact on indicators of marsh plant health (gas exchange, stress enzymes). Plant gas exchange was found to vary with tidal range, marsh elevation, and pore-water salinity. Consequently, future attempts to use this indicator as a measure of plant health must standardize for these environmental factors.
Macro-Crustacean Reproductive Potential Subproject (Kneib). During Year 4, processing of all field samples was completed and attention was focused on crustacean population abundance because earlier comparisons of reproductive output (mean brood size and mean size of individual eggs or embryos) of gravid female crustaceans did not show clear and consistent differences between estuarine sites subject to stressors and those that were not. Our analysis of the abundance data for tanaids (Hargeria rapax) and amphipods (Uhlorchestia spartinophila and Gammarus palustrs) points to lower survival in the juvenile life stages in stressed environments compared to areas with minimal anthropogenic development. The abundance of all species is lower in developed estuaries despite the fact that individual reproductive potential of the survivors does not seem to be affected. This general conclusion had a very interesting twist with respect to the effect of an isopod parasite in populations of grass shrimp (Palaemonetes pugio). The isopod, Probopyrus pandalicola, resides in the gill chamber of the shrimp, renders the host sterile for as long as it is present, and is easily detected with the unaided eye. One of our most interesting findings was that the incidence of parasitism by the isopod in grass shrimp populations was negatively related to the level of environmental stress in the estuary. The general implication of our work suggesting that juvenile stages of crustaceans are most affected by environmental stressors extends to this parasite of grass shrimp as well. The inverse of the incidence of P. pandalicola in estuarine populations of grass shrimp may provide a promising measure of environmental stress. Two manuscripts have been submitted to date as a result of this work and four additional manuscripts are in preparation (see Publications and Presentations).
Future Activities:
This was the final year of the grant and no new activities are planned other than to continue to publish and present the findings of this study as applicable.
Journal Articles on this Report : 8 Displayed | Download in RIS Format
Other project views: | All 32 publications | 14 publications in selected types | All 11 journal articles |
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Type | Citation | ||
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Ewel KC, Cressa C, Kneib RT, Lake PS, Levin LA, Palmer MA, Snelgrove P, Wall DH. Managing critical transition zones. Ecosystems 2001;4(5):452-460. |
R825147 (1998) R825147 (1999) R825147 (2000) |
Exit Exit |
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Levin LA, Boesch DF, Covich A, Dahm C, Erseus C, Ewel KC, Kneib RT, Moldenke A, Palmer MA, Snelgrove P, Strayer D, Weslawski JM. The function of marine critical transition zones and the importance of sediment biodiversity. Ecosystems 2001;4(5):430-451. |
R825147 (1998) R825147 (1999) R825147 (2000) |
Exit Exit |
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Newell SY, Wall VD, Maruya KA. Fungal biomass in saltmarsh grass blades at two contaminated sites. Archives of Environmental Contamination and Toxicology 2000;38(3):268-273. |
R825147 (1998) R825147 (1999) R825147 (2000) R825147 (Final) |
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Newell SY. Fungal biomass and productivity in standing-decaying leaves of black needlerush (Juncus roemerianus). Marine & Freshwater Research 2001;52(2):249-255. |
R825147 (1998) R825147 (1999) R825147 (2000) |
Exit |
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Newell SY. Multiyear patterns of fungal biomass dynamics and productivity within naturally decaying smooth cordgrass shoots. Limnology and Oceanography 2001;46(3):573-583. |
R825147 (2000) R825147 (Final) |
Exit Exit |
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Newell SY. Spore-expulsion rates and extents of blade occupation by ascomycetes of the smooth-cordgrass standing-decay system. Botanica Marina 2001;44(3):277-285. |
R825147 (1998) R825147 (1999) R825147 (2000) R825147 (Final) |
Exit |
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Pennings SC, Moore DJ. Zonation of shrubs in western Atlantic salt marshes. Oecologia 2001;126(4):587-594. |
R825147 (1998) R825147 (1999) R825147 (2000) R825147 (Final) |
Exit Exit |
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Wall VD, Alberts JJ, Moore DJ, Newell SY, Pattanayek M, Pennings SC. The effect of mercury and PCBs on organisms from lower trophic levels of a Georgia salt marsh. Archives of Environmental Contamination and Toxicology 2001;40(1):10-17. |
R825147 (1998) R825147 (1999) R825147 (2000) |
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Supplemental Keywords:
water, watersheds, sediments, marine, estuary, effects, ecological effects, bioavailability, animal, organism, population, stressor, chemicals, toxics, PAHs, heavy metals, organics, indicators, aquatic, habitat, life cycle analysis, public good, conservation, environmental assets, environmental chemistry, biology, ecology, zoology, monitoring, analytical, measurement methods, southeast, Atlantic coast., RFA, Water, Geographic Area, Ecosystem Protection/Environmental Exposure & Risk, Ecosystem/Assessment/Indicators, Ecosystem Protection, exploratory research environmental biology, Chemical Mixtures - Environmental Exposure & Risk, Ecological Effects - Environmental Exposure & Risk, Monitoring/Modeling, Ecological Effects - Human Health, Southeast, Mercury, Ecological Indicators, aquatic, monitoring, health indicator, bacteria, cordgrass, biodiversity, salt marsh estuaries, estuarine ecosystems, regional scale, South Atlantic Bight, aquatic ecosystems, fishRelevant Websites:
http://www.arches.uga.edu/~rtkneib (follow link on index page to research sponsored by U.S. Environmental Protection Agency.)
Progress and Final Reports:
Original AbstractThe perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Conclusions drawn by the principal investigators have not been reviewed by the Agency.