详情

原文传递 Water Quality Management Studies,West Point Lake, Chattahoochee River, Alabama - Georgia

题名：	Water Quality Management Studies,West Point Lake, Chattahoochee River, Alabama - Georgia
作者：	Dean B. Raotke, Cary R. Buell, and Howard A.Perlman
关键词：	Water quality Tissue analysis Limnology West Poist Lake
摘要：	West Point Reservoir is a multiple-purpose project on the Chattahoochee River about 95 kilometers downstream from Atlanta. Urbanization has placed largo demands on the Chattahoochee River, and water quality below Atlanta was degraded, even before Impoundment. Water-quality, bottom-sediment, and fish-tissue samples were collected from West Point Reservoir to determine whether water-quality problems have occurred subsequent to impoundment. Water-quality data were collected at 16 sampling stations within the reservoir and the river downstream of the dam on 17 data-collection trips Water-quality data show that severe hypolimnetic oxygen deficiency occurred in the reservoir after thermal stratification developed in the spring of both 1978 and 1979. This environment favored the release of iron, manganese, phosphorus, and other constituents from the sediments. Concentrations of dissolved iron and manganese in the hypolimnion at the dam pool stations ranged from 20 to 7,700 and 30 to 3,000 micrograms per liter, respectively. During these periods of thermal stratification, dissolved oxygen concentrations in the release water from West Point Reservoir consistently were below State of Georgia water-quality standards at the data collection stations immediately below the reservoir. At these stations, dissolved-oxygen concentrations ranged from 2.0 to 6.3 milligrams per liter, having a mean of 3.8 milligrams per liter. The State of Georgia requires a minimum concentration of 4 milligrams per liter to meet water-quality standards. Hydrogen sulfide odor was also evident in the area immediately downstream from the dam during periods of thermal stratification. The upper lentic, or middle section of the reservoir, showed the greatest biological activity in terms of plankton standing stock, adenosine triphosphate, and chlorophyll production. During thermal stratification periods, phytoplankton and zooplankton standing crops in this section of the reservoir ranged from 39,310 to 666,280 cells per milliliter and 6,000 to 283,740 organisms per liter, respectively. The dominant plankton groups in numbers per unit volume were blue-green algae and rotifers. Algal growth potential assay data showed that the availability of nutrients decreased in response to increases in phytoplankton concentrations from the upper to lower reaches of the reservoir. A maximum algal growth potential value (U.S. Geological Survey method) of 48.0 milligrams per liter was obtained at the uppermost data-collection station at franklin, Georgia, on July 13, 1978, whereas a minimum value of 0.4 milligrams per liter was recorded at the dam pool station in August 1978. "Algal Assay Procedure: Bottle Test" (U.S. Environmental Protection Agency method) Identified nitrogen as the primary growth limiting nutrient in the lotic section and phosphorus as the primary growth limiting nutrient in the lentic section during stratified periods. Also, phosphorus addition in the presence of excess nitrogen appeared to support growth to its maximum. The highest measured concentrations of total iron, total manganese, total phosphorus, total organic carbon, and volatile solids in sediments occurred in the lentic section of the reservoir and at the tributary stations, where silts and clays constitute most of the bottom sediments. PCB's (polychlorinated biphenyls) and chlordane concentrations in the bottom sediments were also relatively high in this section of the reservoir. At these locations, PCB's and chlordane were detected at concentrations up to 740 micrograms per kilogram and 210 micrograms per kilogram, respectively. Young bullhead catfish and largemouth bass tissue samples analyzed for chlorinated hydrocarbons and heavy metals showed substantial amounts of chlordane and PCB's in both whole fish and fillet samples. Concentrations of PCB's and chlordane in fish tissue ranged from 19 to 3,800 micrograms per kilogram and 6.0 to 280 micrograms per kilogram, respectively.
报告类型：	科技报告