Grantee Research Project Results
1999 Progress Report: An Integrative Aquatic Ecosystem Indicator
EPA Grant Number: R826591Title: An Integrative Aquatic Ecosystem Indicator
Investigators: Stemberger, Richard S. , Miller, Eric K.
Institution: Dartmouth College
EPA Project Officer: Packard, Benjamin H
Project Period: October 1, 1998 through June 30, 2003
Project Period Covered by this Report: October 1, 1998 through June 30, 1999
Project Amount: $888,661
RFA: Ecological Indicators (1998) RFA Text | Recipients Lists
Research Category: Ecological Indicators/Assessment/Restoration , Aquatic Ecosystems
Objective:
This project uses measures of the relative supply of carbon (C), nitrogen (N), and phosphorus (P) to integrate watershed, lake, and pelagic zooplankton assemblages in a multitier ecological indicator for monitoring lake integrity. Complex species assemblages are aggregated into simple consumer guilds that reflect relative elemental N and P intracellular requirements of species. Element supply ratios relate a variety of potential risks to lake ecosystem function such as loss of the cool-water refuge, bioaccumulation of toxins, algal turbidity, acidification, and ultraviolet (UV)-B toxicity. These risks are associated with zooplankton assemblage structure along the N:P ratio gradient. Some specific objectives of the project include:
- Evaluate metrics based on the C, N, and P supply of the total dissolved plus seston fraction of lake water as indicators of the character of lake zooplankton assemblage.
- Establish the strength of the linkage between the relative C, N, and P supply from the watershed to the C, N, and P supply to the lake. We will test the hypothesis that N:P, C:N, and C:P ratios in lake water and watershed C, N, and P supply to lakes are significantly influenced by landscape factors related to human land use activity, forest ecosystem composition, and regional air pollution gradients.
- Conduct a landscape characterization analysis of features in the lake-watershed basins that, in conjunction with concurrent watershed-associated stream and groundwater measurements, will be used to develop proxy measures for expected relative C, N, and P supply conditions for lake water.
- Establish zooplankton assemblage-derived variables that reflect risks to ecosystem function, structure, or human health as a function of the elemental supply gradient. These risks include food web simplification reflected by assemblage-derived structural indices like chain length and linkages, the availability of oxic cold-water habitat, algal turbidity, UV-B and aluminum toxicity, and bioaccumulation and transfer efficiency of toxins.
- Conduct a thorough analysis of the sensitivity of zooplankton metrics using a large temporally intensive dataset (Yan, et al., 1996), as well as the spatially extensive dataset in this study and from the existing Environmental Monitoring and Assessment Program (EMAP) dataset. These analyses will establish statistical confidence and power to detect change for measures of lake integrity. We expect to demonstrate that the proposed relative C, N, and P supply indicator can provide a simple, inexpensive, and practical approach to evaluating aquatic ecosystem integrity within the context of the terrestrial environment.
- Develop a hierarchical, ecological-indicator analysis tool designed to aid resource managers in the assessment, monitoring, and prediction of aquatic ecosystem integrity, sustainability, and associated ecosystem risks.
Progress Summary:
Objectives 1?2. In our first field season, we conducted 36 lake visits, including 26 first visits and 10 revisits. Twenty-two lakes were sampled in the Adirondack Mountain and Saint Lawrence Valley Regions of New York, and four lakes were sampled from the Champlain Valley of Vermont. At each lake visit, physical profiles were collected (CTD, DO, pH, and turbidity). Water samples were collected from the epilimnion, metalimnion, hypolimnion, and all tributary streams of each lake. Dissolved and suspended fractions were separated. Plankton tows were conducted for both enumeration and chemical analysis. Sediment samples were collected from mid-lake and tributary mouths. Chemical analysis of water samples is 90 percent complete. Chemical analysis of particulate samples is 50 percent complete. Analysis of sediment samples is just getting underway.
We expect to complete enumeration of this summer's zooplankton samples by this spring. We also are processing biomass of zooplankton from 30 lakes from the 1991?1996 EMAP pilot survey to give us additional leverage in analysis with our more intensive current survey of these same lakes. Zooplankton population data are being converted to biomass/carbon using length-weight regression. This will allow us to integrate the soluble and particulate fractions of C, N, and P in lake and stream water. This biomass program is written using the National Institutes of Health (NIH) Image language that is available from the NIH Web Site (http://rsb.info.nih.gov/nih-image). This macro provides a permanent image archive of the lake zooplankton, and gives many useful data such as magnification and descriptive statistics (N, standard deviation, and coefficient of variation). All data are time stamped and saved as text files for later manipulation and cross-referencing for quality assurance checks. This program will be posted for interested users at the NIH Web Site.
Objective 3. The landscape characterization task involves both field and geographic information system (GIS) analysis components. Fifteen tributary riparian zone locations were visited for field characterizations that included vegetation survey, leaf-litter sampling, and soil characterization and sampling. Chemical analysis of these samples is just getting underway. The bulk of fieldwork related to landscape characterization will take place during 2000. The foundation data layers (topographic factors, land cover?land use, soils, hydrography, climate, and atmospheric deposition) of a regional GIS that will be used for characterization of the study watersheds have been acquired, converted to grid data, reprojected, and resampled as necessary. The generation of riparian zone overlays is in progress. Software for collecting statistics from the GIS was written.
Objective 4. We linked patterns in the structure of zooplankton assemblages of northeastern U.S. lakes to the effects of predators and nutrients on assemblage responses in 1000-L experimental mesocosms. Predator and nutrients (N and P) had highly significant impacts on zooplankton abundances that were consistent with consumer-guild related body size responses to size-selective predation and food quality-related mineral limitation on species growth rates. Phosphorus stimulated the growth of cladocerans and rotifers, while N addition had significant effects on the abundance of calanoid and cyclopoid copepods. Fish greatly reduced large-bodied copepods and large cladocerans, and increased abundances of cyclopoid instars, small cladocerans, and rotifers. The main factors and their interactions revealed in experimental treatments corroborate the factors that explained assemblage structure in natural lakes. Principal component analysis (PCA) of zooplankton from northeastern U.S. lakes contrasted micro-consumer groups like small cladocerans, cyclopoid copepodites, nauplii, and rotifers against calanoid-dominant assemblages. PC-axis 1 was significantly and positively correlated to total N, total P, and young of year fish age-class, and was negatively correlated to N:P ratio. The N:P ratio also was positively and significantly correlated to PC-axis 2, which contrasted calanoid-dominant assemblages in low fertility, low pH lakes having high N:P against lakes having mixed zooplankton assemblages with lower N:P and relatively low concentrations of phosphorus and nitrogen. The results from these independent but mutually supporting approaches greatly strengthen the importance of these factors, especially of nutrients, in controlling structure of zooplankton assemblages in the northeastern United States (manuscript in preparation).
Objective 5. We analyzed the components of variance for zooplankton richness and population indicators in the context of the spatial and temporal conceptual model of the EMAP pilot study of northeastern U.S. lakes. Estimates of sensitivity of candidate metrics were evaluated for their ability to distinguish differences among lakes, their utility to give precise estimates of status, and their ability to detect trends on a regionwide basis and for lake populations in major geographic subregions. Four subregions were defined by their similarity in landscape, land use patterns, and post-glacial drainage histories. Sensitivity of metrics increased in one or more subregions relative to regionwide estimates. Calanoid copepods and large cladocerans were the most sensitive indicators, in that they had 80?90 percent of their variance associated with the lake component for richness and population metrics. Hence, the spatial and temporal components of variance of the zooplankton are more responsive at these smaller subregional scales. Rotifers, cyclopoid copepods, small cladocerans, and minor zooplankton groups had low sensitivity regardless of spatial scale. Indicators of richness generally had higher sensitivity at all spatial scales than did population-based indicators (manuscript in preparation).
Future Activities:
Work will continue in support of Objectives 1?6. Chemical analysis of 1999 lake, plankton, sediment, and soil samples should be completed prior to the upcoming field season. The lake survey will be expanded in the two remaining field seasons (2000/2001). Each year, 30?50 percent of the study lakes will be revisited. The bulk of fieldwork related to landscape characterization will take place during 2000. GIS development, analysis, and modeling will continue through 2001. The development of indicator analysis tools (Objective 6) will take place primarily during 2001.Journal Articles on this Report : 7 Displayed | Download in RIS Format
Other project views: | All 27 publications | 12 publications in selected types | All 11 journal articles |
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Type | Citation | ||
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Allen AP, Whittier TR, Kaufmann PR, Larsen DP, O'Conner RJ, Hughes RM, Stemberger RS, Dixit SS, Brinkhurst RO, Herlihy AT, Paulsen SG. Concordance of taxonomic richness patterns across multiple assemblages in lakes of the northeastern United States. Canadian Journal of Fisheries and Aquatic Sciences 1999;56(5):739-747. |
R826591 (1999) R826591 (2000) |
not available |
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Chen CY, Stemberger RS, Klaue B, Blum JD, Pickhardt PC, Folt CL. Accumulation of heavy metals in food web components across a gradient of lakes. Limnology and Oceanography 2000;45(7):1525-1536. |
R826591 (1999) R826591 (2000) R826591 (2001) R826591 (2002) |
not available |
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Evans CA, Miller EK, Friedland AJ. Nitrogen mineralization associated with birch and fir under different soil moisture regimes. Canadian Journal of Forest Research 1998;28(12):1890-1898. |
R826591 (1999) R826591 (2000) |
Exit |
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Friedland AJ, Miller EK. Major element cycling in a high-elevation Adirondack forest: patterns and change, 1986-1996. Ecological Applications 1999;9(3):958-967 |
R826591 (1999) R826591 (2000) |
Exit Exit |
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Miller EK, Friedland AJ. Local climate influences on precipitation, cloud water, and dry deposition to an Adirondack subalpine forest: insights from observations 1986-1996. Journal of Environmental Quality 1999;28(1):270-277. |
R826591 (1999) R826591 (2000) |
Exit Exit |
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Stemberger RS, Miller EK. A zooplankton- N:P-ratio indicator for lakes. Environmental Monitoring and Assessment 1998;51(1-2):29-51. |
R826591 (1999) R826591 (2000) R826591 (2001) R826591 (2002) R826591 (Final) |
not available |
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Stemberger RS, Chen CY. Fish tissue metals and zooplankton assemblages of northeastern U.S. lakes. Canadian Journal of Fisheries and Aquatic Sciences 1998;53:339-352. |
R826591 (1999) R826591 (2000) |
Exit |
Supplemental Keywords:
air, water, watersheds, limnology, ecology, ecological effects, ecosystem, indicators, aquatic, terrestrial, EMAP, modeling, GIS, northeast., RFA, Scientific Discipline, Water, Ecosystem Protection/Environmental Exposure & Risk, Water & Watershed, Nutrients, Ecology, Hydrology, Ecosystem/Assessment/Indicators, Ecosystem Protection, exploratory research environmental biology, Environmental Chemistry, Ecological Effects - Environmental Exposure & Risk, Air Deposition, Drinking Water, Geology, Watersheds, Ecological Indicators, nutrient transport, aquatic ecosystem, environmental monitoring, nutrient supply, ecological effects, ecological exposure, risk assessment, EMAP, carbon cycling, algae, multi-level indicators, bioavailability, other - risk assessment, algal growth, chemical transport, ecosystem indicators, terrestrial, aquatic ecosystems, phosphorus, carbon storage, integrative indicators, lake ecosystem, landscape characterization, land use, nitrogen, atmospheric depositionRelevant Websites:
http://rsb.info.nih.gov/nih-image
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.