San Joaquin - Tulare NAWQA Program
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What is NAWQA? Study Unit Description Cycle I Surface Water Aquatic Ecology Ground Water Cycle II Surface Water Aquatic Ecology Ground Water Topical Studies: ACT TANC Trends: Surface Water Ground Water NAWQA Personnel Liaison Committee Presentations Publications Study Design Surface Water Ground Water Aquatic Ecology Interdisciplinary Related Studies Ground Water Nitrate Other Studies Publications |
Aquatic Ecology: Cycle I Activities (1991 - 2001)Retrospective AnalysisThe review and analysis of existing aquatic ecological data provide a historical perspective on the aquatic ecology in the Study Unit and are used to assess strengths and weaknesses of available information and to evaluate initial priorities for study design. Reference: Brown, L.R., 1996, Aquatic Biology of the San Joaquin-Tulare Basins, California: Analysis of Available Data Through 1992, U.S. Geological Survey Water-Supply Paper 2471, 89 p. Aquatic Ecology: Study DesignEcological Studies are an integral part of the approach used by NAWQA to assess water quality. Information on biological communities and habitat characteristics contributes to the conceptual model of factors that affect water quality and to improved understanding of the relation among physical, chemical, and biological characteristics of streams. Fixed-Reach Assessments and Intensive Ecological Assessments provide an initial evaluation of the linkages among physical, chemical, and biological conditions within the Study Unit. Ecological Synoptic Studies provide a much more complete geographic representation within the Study Unit, but for a more limited set of physical, chemical, and biological characteristics. Three taxonomic groups--fish, invertebrates, and algae--are sampled because they respond differently to various environmental stresses. Fish are valuable biological indicators of long-term water-resource conditions because they are long lived (years to decades) and have considerable economic value and public interest. Benthic invertebrates (aquatic insects, mollusks, crustaceans, worms) have life cycles (from months to a few years) that are intermediate between fish and algae, have close association with streambed sediments, and can be used for characterizing changes in water quality over small spatial area. Algae respond quickly (within days to weeks) to changes in their environment and serve as valuable biological indicators of rapid changes in water-resource conditions. Gilliom, R.J., Alley, W.M., and Gurtz, M.E., 1995, Design of the National Water-Quality Assessment Program--Occurrence and distribution of water-quality conditions: U.S. Geological Survey Circular 1112, 33 p. Ecological Studies: Fixed Reach AssessmentEcological studies combine descriptions of fish, benthic invertebrate and algal communities, and habitats with physical and chemical data to provide an integrated assessment of water quality within selected environmental settings. These studies are used to assess trends in water quality, and investigate the influence of major natural and human factors on water quality.Data Collected: Algae, benthic invertebrates, and fish were collected, and instream and riparian habitats were described at 13 sites in September 1993. Three types of algae and invertebrate samples were collected:
Ecological Studies: Intensive Ecological AssessmentThe Intensive Ecological Assessment was done to provide information on spatial and temporal variability of biological communities and habitat characteristics. Spatial variability was addressed by sampling three similar reaches at three stream sites (Multi-Reach Assessment). Temporal variability was addressed by sampling one reach at each site annually during the three-year intensive data collection period (1993, 1994, 1995) (Single-Reach, Multi-Year Assessment). Data Collected:
Ecological Studies: Community Assessment SynopticThe Ecological Synoptic Study completed in 1994 had two primary purposes. First, additional sites were sampled on the lower mainstem San Joaquin River and the Stanislaus, Tuolumne, and Merced Rivers, below the reservoirs to improve spatial coverage of the Fixed-Reach Assessment on each river and to facilitate comparison of ecological communities among rivers. Second, a number of locations upstream of Lake McClure on the Merced River were sampled, including several sites in Yosemite National Park. Data from these samples were used to analyze the ecological communities of the least-altered Sierra Nevada river in the study unit and to establish a database of background information for future studies. Data Collected:Fish and algae data were collected at 7 sites in 1993, 25 sites in 1994. A total of 32 sites were sampled. References: Brown, L.R., 2000, Fish communities and their associations with environmental variables, lower San Joaquin River drainage, California: Environmental Biology of Fishes 57:251-269. Brown, L.R., and May, J.T., 2000, Benthic macroinvertebrate assemblages and their relations with environmental variables in the Sacramento and San Joaquin Drainages, California: U.S. Geological Survey Water-Resources Investigations Report 00-4125, 25 p. Brown, L.R., and May, J.T., 2000, Macroinvertebrate assemblages on woody debris and their relations with environmental variables in the lower Sacramento and San Joaquin river drainages, California: Environmental Monitoring and Assessment 64:311-329. Leland, H.V., L.R. Brown,and D.K. Mueller., 2001, Distribution of algae in the San Joaquin River, California, in relation to nutrient supply, salinity, and other environmental factors. Freshwater Biology 46:1139-1167. Aquatic Ecology DataAquatic Ecology Data include descriptions of fish, benthic invertebrate and algal communities, and habitat. At this time only the fish data is available. Fish Data:The following files are in a tab-delimited ascii format. An explanation of the format and content of the files is in the file readme.fsh. A listing of the site information is in the file fish.sitetable. References: Cuffney, T.F., Gurtz, M.E., and Meador, M.R., 1993, Methods for collecting benthic invertebrate samples as part of the National Water-Quality Assessment Program, U.S. Geological Survey Open-File Reports 93-406, 66 p. Meador, M.R., Cuffney, T.F, and Gurtz, M.E., 1993, Methods for sampling fish communities as part of the National Water-Quality Assessment Program, U.S. Geological Survey Open-File Report 93-104, 40 p. Meador, M.R., Hupp, C.R., Cuffney, T.F., Gurtz, M.E., 1993, Methods for characterizing stream habitat as part of the National Water-Quality Assessment Program, U.S. Geological Survey Open-File Report 93-408, 48 p. Porter, S.D., Cuffney, T.F., Gurtz, M.E., and Meader, M.R., 1993, Methods for collecting algal samples as part of the National Water-Quality Assessment Program, U.S. Geological Survey Open-File Report 93-409, 39 p. Low-Intensity Phase SamplingBiological data collection include annual single-reach assessments of fish, invertebrate, and algal communities, and Level I habitat characterization. |