Limnological features of a culturally eutrophic pond in Southern California

Includes bibliographical references (pages 58-62)A study of a culturally eutrophic pond including structural features and their dynamics was carried out. Data analysis from measured physical, chemical, and biological parameters collected over a 15 week period from a 15 million gallon pond receiving secondary treated wastewater indicated a distinct and eutrophic character. \ud Physical and chemical measurements revealed a marked degree of stratification and correlation for dissolved oxygen, temperature, and pH. Low Secchi disk transparencies and high concentrations of nitrogen and phosphorous are primary evidence of cultural enrichment. Evidence indicates that carbon may be acting as a limiting nutrient for the pond's phytoplankton. \ud Phytoplankton densities and distributions varied widely. Genera common to eutrophic systems were dominant-blue-green algae of the genus Oscillatoria and green algae such as Ankistrodesmus sp. and Sphaerocystis sp. . Populations of net phytoplankton were not dependent or influenced by the measured nutrients - nitrogen and phosphorous. Photosynthetic activity clearly influences the chemical equilibrium of the pond. (See more in text.