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Linda J. Britton

Publications and source records attributed to Linda J. Britton.

7 recordsLinked to original sources

Water-quality characteristics of selected lakes and reservoirs in Colorado

During the summers and autumns of 1973, 1974, and 1975, water-quality data were collected and compiled for 56 lakes and reservoirs in Colorado. The lakes and reservoirs sampled range from large reservoirs in the eastern part of the State to smaller natural lakes in the higher western parts of the Colorado Plateaus. The smallest body of water sampled was Anderson Reservoir No. 1 with a surface area of 47 acres in Mesa County, and the largest was Najajo Reservoir with a surface area of 15,600 acres in Archuleta County. The report includes physical, chemical, and biological water-quality data collected as a part of each lake or reservoir reconnaissance. Also included are data on drainage area, water-surface altitude, surface area,depth, storage capacity, and principal uses, obtained from various governmental agencies or the owner or regulating agency of each lake or reservoir. A subjective evaluation of the trophic (enrichment) state is presented based on nutrient and phytoplankton concentrations and the dissolved-oxygen distribution. In addition, a numerical trophic-state index, based on Secchi-disk transparency (a measure of light penetration) is reported, to show trophic comparisons between lakes and reservoirs. (USGS)

Open-File Report

Data compilation of periphyton colonized on artificial substrates placed in the Sacramento and Feather rivers, California, 1975

Periphyton was collected from artificial substrates placed in the Sacramento and Feather rivers, California, and analyzed to determine the rate of colonization and succession of periphyton types with time. Samples for determination of water-quality characteristics, especially suspended-sediment concentrations, that might have a direct effect on the growth of periphyton were collected during each station visit. This paper describes the methods of data collection and presents qualitative and quantitative findings of periphyton collected during two colonization periods (August 5-September 5, 1975, and November 28-December 29, 1975) and associated water-quality data.

California

Periphyton and phytoplankton in the Sacramento River, California, May 1972 to April 1973

Periphyton and phytoplankton samples were collected monthly at five sites in the Sacramento River between May 1972 and April 1973. Periphyton were analyzed for species identification and biomass, and phytoplankton were analyzed for species identification and concentrations. The results were used to assess biological water-quality conditions in the river and to compare phytoplankton types and concentrations at three sites with those in 1960-61. Diatoms were the dominant group in both numbers and types of periphyton and phytoplankton. The number of genera and frequency of occurrence of periphyton increased downstream. The periphyton biomass decreased downstream and with succeeding monthly sampling periods. The highest productivity was at site B, below Red Bluff, probably because the Red Bluff Diversion Dam provides optimum conditions for periphyton growth. The decreasing productivity downstream is probably a function of higher sediment concentrations. The periphyton biomass ranged from 0.00 to 0.56 grams per square meter per day throughout the study period. Phytoplankton concentrations and diversity increased downstream. The highest phytoplankton concentration was 980 organisms per milliliter at site D, above Knights Landing, in September. The diversity indices ranged from 0.95 to 3.88 for all sites throughout the study period. Fewer phytoplankton genera were collected in 1972-73 than in 1960-61, but the generic composition was similar. Total phytoplankton concentrations were nearly always higher in 1960-61 than in 1972-73. Green algal concentrations were significantly higher ( p <0.05) at site C and diatoms were significantly higher at all three sites in 1960-61. Blue-green algal concentrations were higher in 1972-73, but differences between the two time intervals were not significant.

California

Limnological data from selected lakes in the San Francisco Bay region, California

Limnological data were compiled on 21 lakes in the San Francisco Bay area. The data were obtained from regulating agencies and from recent surveys made by the U.S. Geological Survey. The history of each lake and of its respective regulating agency is presented, along with methods used for data collection and analyses. The largest reservoir, Lake Berryessa, has a volume of 1,600,000 acre-ft (1,975 hm 3 ), with a drainage. area of 576 mi 2 (1,490 km 2 ). Pilarcitos Lake is one of the smallest reservoirs, with a volume of 3,100 acre-ft (3. 8 hm 3 ) and a drainage area of 3. 80 mi 2 (9.84km 2 ). Eleven of the 21 reservoirs are open to the public for recreation. The most intensive shoreline development and use is at Lake Berryessa and Lake Merced. All but three of the 21 reservoirs (not including Upper Crystal Springs Reservoir) were thermally stratified during the summer. Eight of the reservoirs showed evidence of dissolvedoxygen depletion during the summer. Lafayette Reservoir and Loch Lomond are mechanically aerated in order to increase the dissolved-oxygen concentration and lower the surface water temperature. The lake waters ranged from the hard (320 mg/1 CaC0 3 ) of Calero Reservoir, to the soft (27 mg/1 CaC0 3 ) of Upper Crystal Springs Reservoir. Drainage from abandoned mercury mines in Santa Clara County has resulted in mercury concentrations in Calero and Lexington Reservoir fish which exceed U.S. Food and Drug limitations (0.5 &mu; /g) for acceptability of mercury in fish used for human food. In Loch Lomond, four major production periods of the blue-green algae, Anabaena sp . , occurred from May to October, 1967-69. Blue-green algae were the most numerous algae in Lake Del Valle from March through July 1971, with 5,400 blue-green algal organisms per millilitre collected in April.

California