Thesis (M.S.)--Oregon State University, 1992. / Typescript (photocopy). Includes bibliographical references (leaves 87-90). Also available on the World Wide Web.

Thesis (Ph. D.)--University of Wisconsin--Madison, 1947. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 121-128a).

Thesis (Ph. D.)--University of Wisconsin--Madison, 1973. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

Thesis (M. Sc.)--York University, 1998. Graduate Programme in Geography. / Typescript. Includes bibliographical references (leaves 223-234). Also available on the Internet. MODE OF ACCESS via web browser by entering the following URL: http://wwwlib.umi.com/cr/yorku/fullcit?pMQ39210.

Soil, water, and climatic classification systems are reviewed as background for the construction of a classification system for earthen aquaculture ponds. The physical and chemical properties of important soil types are also reviewed because of the critical role that the soil plays in earthen pond systems. A pond classification system is constructed using key elements from established climate, water, and soil classification systems, and its use as a management tool is demonstrated. Additional benefits of pond classification are discussed. Functional relationships pertaining to a particular management practice--the application of lime--are examined for seven classes of acid soils. Theoretical and empirical models of pH-percent base saturation relationships are evaluated using data from United States soils. Selected models are partially validated using an independent set of data and incorporated into a lime requirement determination model. A table of lime requirement estimates based on initial soil pH values is calculated for each soil class. Partial validation of the classification system is achieved by ANOVA for the cation exchange capacities of the soils, by fitting the selected pH-percent base saturation models to data from an independent source, and by comparison of the estimated lime requirements with previously published guidelines. Possible reasons for weaknesses in the classification system, the pH-percent base saturation models, or the approach to lime requirement determination are explored, and areas requiring further research are identified. Additional uses and benefits, and further validation and refinement of the classification system are discussed. It is concluded that the proposed classification is a good first approximation that provides a basis for further work. / Graduation date: 1992

A detailed limnological study of Clark's Borrow Pit Pond (SW* Sec. 30 T22N R9E, Delaware County, IN) was conducted from the spring of 1978 through the fall of 1979 to ascertain what factors regulate the abundance of Volvox aureus, a major phytoplanktor of the pond. This algal species often dominates the spring and sometimes fall phytoplankton blooms that occur annually, but disappears fran the plankton throughout the remainder of the year.Laboratory growth experiments suggest that the spring peak of V. aureus (105 colonies ml-l in 1978) is most likely induced by the high nutrient levels in the pond (total P = 4.6 µmoles ℓ-1; NO3 - N + NH3 - N = 11.8 Wholes 2-1) and warming temperatures. Competition from other algal species is reduced at this time by the presence of the zooplanktor Da hnia ambigua which effectively grazes all but the V. aureus colonies. Decreased nutrient levels in the summer months (total P = 1.0 µmoles Z-1 N03 - N + NH3 - N = 1.3 µmoles Z-1 ) restrict the abundance of V. aureus, and other algal species (notably blue-greens) dominate. Two of these species, Oscillatoria sp. and Microcystis sp., were shown to exhibit no allelopathic influences on the growth of V. aureus. However, experiments suggested a heat labile inhibitor or inhibitors of V. aureus may periodically affect its growth in the pond. Increasing nutrient levels in the fall sometimes induce a second V. aureus bloom, but this declines rapidly as the water temperature drops below 10° C. Consequently, the abundance of V. aureus in Clark's Pond is influenced mainly by abiotic factors (nutrient availability and water temperature) and only to a lesser degree by biotic factors (grazing and competition).

Thesis (M.S.)--Marshall University, 2004. / Title from document title page. Document formatted into pages; contains vii, 82 p. including illustrations. Includes abstract. Includes bibliographical references (p. 36-38).

Production rates of seven species of fish, along with food-web interactions, were determined for one year in a pond. Production of fish in the pond amounted to 208.9 q/m2/yr. Over 95% of the production occurred in the summer, with Y of Y fish contributing 83.8%. There were two food-web interactions observed in Y of Y fishes: crappie vs. bass and bullhead vs. sunfish. When Y of Y fish shifted to benthic diets in the spring, the small biomass of benthos available could not sustain the larger biomass of fish. Competition for the available food resulted in decreased production rates for the fish community.

Thesis (Ph. D.)--University of Chicago, Dept. of Ecology and Evolution, August 2003. / Includes bibliographical references. Also available on the Internet.

This study investigated the relationship between flood duration of beaver ponds in eastern Ontario and their productivity for waterfowl. The primary objective was to assess the effect of removing water from a beaver pond for one year had on the subsequent productivity of the wetland. Productivity was estimated by sampling water chemistry, standing crops of aquatic invertebrates, vertebrates, algae and vegetation composition and distribution in naturally occurring and managed beaver ponds of varying ages during 1994 and 1995. Three ponds in each of the following categories were sampled; managed ponds reflooded in 1993, managed ponds reflooded in 1991, naturally occurring beaver ponds reflooded in 1992-93, and naturally occurring old flood ponds ($>$5 years old). / Results from this study indicate that beaver pond productivity is negatively affected by flooding duration. Removal of a portion of the beaver dam on old flood ponds may be an effective means of rejuvenating the wetland. Positive effects on the productivity of the wetland should be realized for several years after reflood. Variability in results indicates that other environmental variables were also affecting the overall productivity of beaver ponds. (Abstract shortened by UMI.)