Application of Stable Isotope Techniques to Identifying Foodweb Structure, Contaminant Sources, and Biogeochemical Reactions in the EvergladesEntry ID: USGS_SOFIA_kendall_stable_isotopes
Abstract: This is the largest isotope foodweb study ever attempted in a marsh ecosystem, and combines detailed, long-term, trophic and biogeochemical studies at selected well-monitored USGS/SFWMD/FGFFC sites with limited synoptic foodweb data from over 300 sites sampled during 1996 and 1999 by a collaboration with the EPA-REMAP program. The preliminary synthesis of the biota isotopes at USGS and 1996 REMAP ... sites provides a mechanism for extrapolating the detailed foodwebs developed at the intensive USGS sites to the entire marsh system sampled by REMAP. Furthermore, this unique study strongly suggests that biota isotopes provide a simple means for monitoring how future ecosystem changes affect the role of periphyton (vs. macrophyte-dominated detritus) in local foodchains, and for predictive models for foodweb structure and MeHg bioaccumulation under different proposed land-management changes. Data are available for the following sites: Cell 4, ENR-OUT, L7, Cell 3, LOX, North Holeyland, E0, F1, U3/Glory Hole, L35B, 2BS, L67, 3A-15, 3A-TH, Lostmans Creek, North Prong Creek, TS-7, and TS-9 for the plants and animals found at each site.
A first step of the Everglades restoration efforts is "getting the water right". However, the underlying goal is actually to re-establish, as much as possible, the "pre-development" spatial and temporal distribution of ecosystems throughout the Everglades. Stable isotope compositions of dissolved nutrients, biota, and sediments provide critical information about current and historic ecosystem conditions in the Everglades, including temporal and spatial variations in contaminant sources, biogeochemical reactions in the water column and shallow subsurface, and trophic relations. Hence, the scientific focus of this project is to use stable isotope techniques to examine ecosystem responses (especially variations in foodweb base and trophic structure) to temporal and spatial variations in hydroperiod and contaminant loading for the entire freshwater Everglades. The major "long-term" objectives of this project have been to: (1) determine the stable C, N, and S isotopic compositions of Everglades biota, (2) use bulk and compound-specific isotopic ratios to determine relative trophic positions for major organisms, (3) examine the spatial and temporal changes in foodweb structures across the ecosystem, especially with respect to the effect of anthropogenically derived nutrients and contaminants from agricultural land uses on foodwebs, (4) evaluate the effectiveness of isotopic techniques vs. gut content analysis for determining trophic relations in the Everglades, (5) evaluate the role of algae vs. detritus/microbial materials in foodwebs for the entire freshwater marsh part of the Everglades, and (6) work with modelers to correctly incorporate food web and MeHg bioaccumulation information into predictive models. More recent and specific objectives include: (1) link our data on seasonal and temporal differences in foodweb bases and trophic levels with SFWMD, FGFFC, and USGS Hg datasets (first for large fish and, more recently, for lower trophic levels), (2) investigate the effects of seasonal/spatial changes in nutrients, water levels, and reactions on the isotopic compositions at the base of the foodweb (that affect our interpretation of relative trophic positions of organisms), and (3) continue our efforts to link our foodweb isotope data from samples collected at USGS-ACME and EPA-REMAP sites with the spatial environmental patterns observed by the REMAP program.
This work started as part of the Aquatic Cycling of Mercury in the Everglades (ACME) project in 1996 and was made a separate project in 2000.
Data Set Citation
Dataset Originator/Creator: Carol Kendall Bryan E. Bemis; Scott D. Wankel
Dataset Title: Application of Stable Isotope Techniques to Identifying Foodweb Structure, Contaminant Sources, and Biogeochemical Reactions in the Everglades
Dataset Release Date: 2005
Data Presentation Form: spreadsheetOnline Resource: http://sofia.usgs.gov/projects/int_geochem_foodweb/
Start Date: 1995-03-01Stop Date: 1999-10-31
TERRESTRIAL HYDROSPHERE > WATER QUALITY/WATER CHEMISTRY > CONTAMINANTS
TERRESTRIAL HYDROSPHERE > WATER QUALITY/WATER CHEMISTRY > STABLE ISOTOPES
BIOSPHERE > TERRESTRIAL ECOSYSTEMS > WETLANDS > MARSHES
BIOSPHERE > AQUATIC ECOSYSTEMS > WETLANDS > MARSHES
BIOSPHERE > ECOLOGICAL DYNAMICS > ECOSYSTEM FUNCTIONS > BIOGEOCHEMICAL CYCLES
BIOSPHERE > ECOLOGICAL DYNAMICS > ECOSYSTEM FUNCTIONS > TROPHIC DYNAMICS
Access Constraints None
Use Constraints These data are subject to change and are not citeable until reviewed and approved for official publication.
Data Set Progress
Distribution Format: MS Excel
Role: TECHNICAL CONTACT
Email: ckendall at usgs.gov
U.S. Geological Survey 345 Middlefield Road, MS 434
City: Menlo Park
Province or State: CA
Postal Code: 94025
Role: DIF AUTHOR
Email: alicia.m.aleman at nasa.gov
Goddard Space Flight Center Code 610.2
Province or State: MD
Postal Code: 20771
Haitzer, M., Aiken, G. R.; Ryan, J. N., 2002, Binding of Mercury (II) to Dissolved Organic Matter: The Role of the Mercury-to-DOM Concentration Ration, Environmental Science and Technology, v. 36, Washington, DC, American Chemical Society, The entire paper is available from the Environmental Science and Technology Journal web site; however, a journal subscription is required. http://sofia.usgs.gov/publications/papers/hg_dom_binding/
Kendall, Carol, Bemis, Bryan; Wankel, Scott, Silva, Steve; Chang, Cecily; Campbell, Linda, Lessons from the Everglades: Atypical isotope patterns in a complex ecosystem, 2001, Menlo Park, CA, U.S. Geological Survey. http://sofia.usgs.gov/publications/posters/lessons-evergl/
Kendall, C., Silva, S. R.; Stober, Q. J.; Meyer, P., 1998, Mapping spatial variability in marsh redox conditions in the Florida Everglades using biomass stable isotopic compositions, EOS Transactions, v. 79, Washington, DC, American Geophysical Union.
Rumbold, D. G., Fink, L. E.; Laine, K. A.; Niemczyk, S. L.; Chandrasekhar, T.; Wankel, S. D.; Kendall, C,
2002, Levels of mercury in alligators (Alligator mississippiensis) collected along a transect through the Florida Everglades, The Science of the Total Environment, vol. 297, issues 1-3, Amsterdam, The Netherlands, Elsevier Science B.V., Only the abstract is available online; a journal subscription is required to access the full article.
McCutchan, Jr., James H., Lewis, Jr., William M.; Kendall, Carol; McGrath, Claire C., 2003, Variation in trophic shift for stable isotope ratios of carbon, nitrogen, and sulfur, Oikos, vol. 102, issue 2, Lund, Sweden, Nordic Ecological Society, Only the abstract is available free of charge. A journal subscription is required for access to the full article.
To view the abstract, click on the link under Journal Articles at, http://sofia.usgs.gov/projects/int_geochem_foodweb/
Extended Metadata Properties
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Creation and Review Dates
DIF Creation Date: 2007-09-17
Last DIF Revision Date: 2014-02-03