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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

An Internet survey of private pond owners and managers in Texas

Schonrock, April Elizabeth 01 November 2005 (has links)
This study was designed to integrate a mailing list-based survey with an internetbased presentation/response in order to take into account the trend toward selfadministration that is evident in everyday interactions with automated services that have taken the place of personal interactions. A random sample of 2,999 was taken from applicants for Triploid Grass Carp Permits from the Texas Parks and Wildlife Department. A forty-nine question survey was constructed containing five sections: general pond characteristics, physical pond characteristics, aquatic vegetation, fish and other wildlife, and management goals. The primary emphasis of this study was to determine what specific problems Texas pond owners faced, how widely these problems occurred, and where pond owners got the information they used to deal with pond management problems. A secondary emphasis of the project was to examine the potential presented by the Internet for use in this type of information gathering and distribution for Texas Cooperative Extension. An overall response rate of 21.3% (excluding non-deliverables and unusable submitted surveys) was obtained. Summary statistics for each question were calculated and then compared in order to gain a clearer picture of the pond management practices employed by Texas pond owners. These results indicated some initial discrepancies between pond owners?? management practices and current management recommendations, most dramatically where aquatic vegetation was concerned. The internet-based survey methodology worked effectively to lower the cost of distribution and the workload of data entry when compared to the mail survey. These benefits outweighed the disadvantages caused by survey error with the new methodology.
32

Factors regulating the abundance of phytoplankton, particularly Volvox aureus, in a small pond

Hunchberger, Robert A. January 1982 (has links)
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).
33

The ecological and social dynamics of Inuit narwhal foraging at Pond Inlet, Nunavut /

Lee, David S. January 2005 (has links)
Research over the past several decades on the nature of Inuit hunting of narwhals has focused upon harvesting technologies and the traditional ecological knowledge of modern hunting of the species. However, as much as such work has contributed to our understanding of Inuit and narwhal interaction, less is known about contemporary Inuit hunting behaviour of narwhal. The research presented in this dissertation redresses this gap by providing a detailed behavioural description and analysis of the Inuit narwhal hunting in two critical environments utilized by the Inuit of Pond Inlet---those of the spring floe-edge and the summer open water. / This information and its analysis are presented through three manuscripts. The first manuscript forms the analytical basis of the behavioural description by presenting through the use of a decision flow chart, the parameters that affect narwhal hunting. The second and third manuscript explore different foraging strategies involved in several major decisions the Inuit typically face when pursuing narwhal at the floe-edge (Manuscript Two) and in the open water environment (Manuscript Three). The data pertinent to the major decision factors influencing actions in both environments were obtained through participant observation, supplemented by interviews with hunters and elders. / The main results of this research pertain to the different, but complementary, strategies employed by Mittimatalingmiut (Pond Inlet Inuit) hunters during the floe-edge and ice free seasons, as well as during the transition between the two. Before break-up, the most frequent method employed in floe-edge and outpost camp hunts is an ambush or a sit-and-wait strategy. Interestingly, during the transition between floe-edge and complete open water, Pond Inlet Inuit utilized both sit-and-wait and pursuit hunting strategies to maximize their hunting opportunities.
34

Effect of sodium nitrate treatment on water and sediment quality in laboratory and pond studies

Chainark, Suwanit, Boyd, Claude E., January 2008 (has links)
Thesis (Ph. D.)--Auburn University. / Abstract. Vita. Includes bibliographical references (p. 73-80).
35

Use of primary nursery ponds for red snapper larvae culture and associated zooplankton dynamics

English, Daniel Patrick, Phelps, Ronald Paul, January 2008 (has links) (PDF)
Thesis (M.S.)--Auburn University, 2008. / Abstract. Vita. Includes bibliographical references.
36

Postglacial vegetation, fire, and climate history of Blacktail Pond, Northern Yellowstone National Park, WY

Huerta, Mariana Angelica. January 2008 (has links) (PDF)
Thesis (MS)--Montana State University--Bozeman, 2008. / Typescript. Chairperson, Graduate Committee: Cathy Whitlock. Includes bibliographical references (leaves 50-54).
37

A Short Cultural History of the Thoreau Society

Neville, Caitlyn January 2022 (has links)
Thesis advisor: Min Song / The Thoreau Society is the oldest literary society for an American author in the United States, as well as an important force for environmental preservation in Concord, Massachusetts. Since its founding in 1941 the society has used Thoreau's texts, philosophy, and character to bring people together and, during the 1950s, save Walden Pond from future development. In doing so I argue the society essentially bridged literature and environmentalism in a way that created tangible change. Though they are a complicated group that can and should be seen from a critical lens, their triumphs speak to a broader connection between writing and preservation that alters how present-day readers view Thoreau's work. Thus, the thesis will demonstrate how examining the origins, dynamics, tactics, motivations, and achievements of the society grants a clearer understanding not just of how Walden Pond came to be preserved in Concord, but how Thoreau has come to exist in a modern light. / Thesis (BA) — Boston College, 2022. / Submitted to: Boston College. College of Arts and Sciences. / Discipline: Departmental Honors. / Discipline: English.
38

The ecological and social dynamics of Inuit narwhal foraging at Pond Inlet, Nunavut /

Lee, David S. January 2005 (has links)
No description available.
39

Continuous simulation of groundwater use and effluent discharge in catfish (Ictalurus punctatus) ponds at five locations in the Southeast U.S

Triyono, Sugeng 11 August 2007 (has links)
Long-term climatological data were used to evaluate the effectiveness of a drop/add management strategy to reduce groundwater use and effluent discharge in catfish ponds in the southeast U.S.. A drop/add approach is based on the creation of a storage volume in the pond for rainfall collection. The storage volume is created by allowing water level in the pond to decrease until some minimum level is reached. When the minimum level is reached, the pond is partly refilled, leaving the remaining volume available to capture incident precipitation. In this way, the role of precipitation in the water budget is increased. In the process, groundwater use and effluent release both become smaller. The data consisted of 45 year precipitation and evaporation records from Fairhope, AL; Clemson, SC; Stoneville, MS, Stuttgart, AR; and Thomsons, TX. The data were used in a water balance levee pond model that included precipitation, evaporation, infiltration, overflow, groundwater pumping, and draining. The model appeared to indicate that the drop/add management scheme is an effective strategy to reduce groundwater use and effluent discharge. The simulated results showed that variation of climate in the southeast U.S. was an important determinant of performance of the drop/add management scheme. At locations with positive P-0.8E, zero groundwater use could be achieved with low drop depths. At location with negative P-0.8E, zero groundwater use could be achieved for about 50% of the 45 simulated years. The model also indicated that effluent discharge cannot be avoided at most locations except at location with very low (negative) P-0.8E. The model also indicated that 65 to 100% of annual precipitation (depending on the P-0.8E?s of the locations) can be captured and used in the ponds. Rainwater contribution to the total water budget ranged from 90 to 100%. The sensitivity analysis showed that model sensitivity to pan coefficient and infiltration rate was affected by infiltration rate and pond water storage capacity (drop depth). The model was more sensitive to pan coefficient rather than to infiltration rate at lower infiltration rates and vice-versa.Both sensitivities of the model, however, increased when pond water deeper storage capacity was used.
40

Trophic Structure and Energy Flow in a Texas Pond

Childress, William M. 08 1900 (has links)
Annual energy flow and mean annual biocontent of eighteen compartments were determined for a 0.94 ha north central Texas pond ecosystem. Annual primary production was 7,780 kcal m^-2 yr^-2, and community production-to-respiration ratio was 1.49. One-third of annual primary production accumulated on the substrate as silt and sedimentation. Community production, production-respiration ratio, and biocontents of all compartments except aquatic insects were large in summer, small in winter. Biocontents of four trophic levels in the pond were all of the same order of magnitude, approximately 50 kcal m^-2. Suspended and benthic organic material forprimary consumers and terrestrial insects for tertiary consumers were substantial allochthanous energy imports into the pond system.

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