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Plankton Community Response to Dechorination of a Municipal Effluent Discharged into the Trinity River

Description: Chorine is used by the Village Creek Waste Water Treatment Plant to kill pathogenic microorganisms prior to discharge of the effluent into the Trinity River. The residual chlorine in the river impacted aquatic life prompting the U.S. Environmental Protection Agency in December 1990 to require dechlorination using sulfur dioxide. One pre-dechlorination and four post-dechlorination assessments of phytoplankton, periphyton, and zooplankton communities were conducted by the Institute of Applied Sciences at the University of North Texas. Dechlorination had no effect on the phytoplankton community. The periphyton community exhibited a shift in species abundance with a more even distribution of organisms among taxa. No change occurred in zooplankton species abundance, however, there was a decrease in zooplankton density following dechlorination.
Date: December 1994
Creator: Bryan, Brynne L. (Brynne Lee)
Partner: UNT Libraries

Size Fractionation of Metabolically Active Phytoplankton and Bacteria in Two Diverse Lentic Systems

Description: Simultaneous size fractionation of plankton populations associated with NaH^14CO_3 and ^3H-glucose uptake was employed in eutrophic Lake Texoma (Texas and Oklahoma) and oligotrophic Flathead Lake (Montana). Autoradiography was utilized to determine the role of specific microorganisms in community metabolism. Ultraplankton (0.45-10 μm) dominated plankton numbers and metabolic activity in both aquatic systems. Many of the most abundant species were not the most productive, in terms of inorganic C fixation. Rates of heterotrophic uptake of ^3H-glucose were small in comparison to photolithotrophic uptake in both lakes, Photoheterotrophy was more extensive in Flathead Lake, Autoradiographs indicated that bacteria were responsible for observed photoheterotrophy. Oscillatoria sp. exhibited. mixotrophy in Lake Texoma,
Date: August 1980
Creator: Ellis, Bonnie K.
Partner: UNT Libraries

Use of ATP as a Planktonic Biomass Indicator in Reservoir Limnology

Description: A series of laboratory experiments and a field investigation were conducted to closely define the application of the ATP assay and ATP as a planktonic biomass estimator for routine use in reservoir limnology. The laboratory experiments verified the published range of C:ATP ratios (i.e. 250:1) as a conversion factor for ATP to biomass in cultured selected genera of freshwater algae, except for the species of blue-green algae examined. The field investigation conducted at Moss Reservoir included organic carbon measurements with ATP biomass in size classes on a depth basis. The ATP biomass varied seasonally and with depth; the best significant mtltiple correlation was between organic carbon and the smallest size class (.45 to 10 um) and total net plankton biomass (.45 to 165 um). Daily monitoring of biomass in size classes demonstrated the sensitivity of the technique.
Date: August 1978
Creator: Perry, William B.
Partner: UNT Libraries

Ecological Studies of the Hudson River Near Indian Point

Description: "The general purpose of [this study is] to determine the ecological responses of the [Hudson] River to various classes of potential pollutants, so that the discharge of waste heat and radionuclides from the Indian Point Power Plant can be evaluated in context with these" (p. 1).
Date: April 1971
Creator: New York University. Medical Center. Institute of Environmental Medicine.
Partner: UNT Libraries

Spatial and Temporal Variability of Plankton Stocks on the Basis of Acoustic Backscatter Intensity and Direct Measurements in the Northeastern Gulf of Mexico

Description: Report detailing the size and concentration of zooplankton in the water column using backscattered acoustic signals of acoustic Doppler current profilers
Date: August 2001
Creator: Scott, Rebecca L.; Biggs, Douglas C. & DiMarco, Steven F.
Partner: UNT Libraries Government Documents Department