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Man-made lakes and waterways within residential developmentsGoodin, Julius Anderson 08 1900 (has links)
No description available.
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Mathematical modeling of '1'3'7Cs and '2'1'0Pb transport in lakes, their sediments, and surrounding catchmentSmith, James Thompson January 1993 (has links)
No description available.
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Reservoir sedimentation and land use change in north west EnglandStott, A. P. January 1985 (has links)
No description available.
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Biogeochemical dynamics of an intermittently open estuary: a field and modelling study.Everett, Jason D., School of Biological, Earth & Environmental Science., UNSW January 2007 (has links)
This thesis presents a combined modelling and observational study of an intermittently open and closed lake or lagoon (ICOLL) in south-eastern Australia. ICOLLs are a common, yet vulnerable type of estuary characterised by low freshwater inflow leading to a sand berm being formed across the entrance preventing oceanic flushing. The accumulation of nutrients during the closed phase, and the increased water residence time, can have detrimental effects on the estuary if the nutrient load cannot be assimilated. The general aim of this study was to develop a quantitative understanding of ecological processes in Intermittently Closed and Open Lakes or Lagoons (ICOLLs) through a combination of field work and ecological modelling. The field-based component of the studied was completed in Smiths Lake, NSW Australia. The field data shows that concentrations of NH3, NOx and Chlorophyll a in Smiths Lake gradually increases over time between the two studied opening events, before declining while the lake is open to the ocean. Phosphorus concentration is relatively low throughout both cycles. Of the 2 opening events, one was long (~ 3.5 months) and one was short (~3 weeks). Initially ammonia concentrations following this short open period were 2-4 times higher than the initial values from the previous 2 closures. The reduced open phase also resulted in more persistent stratification. The observations show that the duration of the open/closed phases will influence the physiochemical characteristics of the water column. A spatially resolved, eleven-box ecological model was developed for Smiths Lake. The process descriptions in the ecological model are based on a combination of physical and physiological limits to the processes of nutrient uptake, light capture by phytoplankton and predator/prey interactions. An inverse model is used to calculate mixing coefficients from salinity observations. When compared to field data, the ecological model obtains fits for salinity, nitrogen, phosphorus, chlorophyll a and zooplankton that are within 1.5 standard deviations of the mean of the field data. Simulations show that nutrient limitation (nitrogen and phosphorus) is the dominant factor limiting growth of the autotrophs during both the open and closed phases of the lake. The model is characterised by strong oscillations in phytoplankton and zooplankton abundance,typical of predator-prey cycles. A sensitivity analysis was completed using a simplified 1-box configuration, coupled with the existing ecological model. When small perturbations in the initial conditions of DIN, phytoplankton and zooplankton are implemented, the standard deviations of the state variables strongly attract to a declining oscillation, showing the variation between runs decreasing with time. The most sensitive parameters in the model were the feeding efficiency of small and large zooplankton, and the mortality of epiphytes and small zooplankton which all had normalised sensitivities of 1.28, 1.11, 1.01 and 1.05 respectively for a 10% change in parameter value. The non-linearity of the model is illustrated by increasing the percentage change of the parameter. For a 25% change in feeding efficiency of small and large zooplankton, the normalised sensitivity increased to 1.28 and 1.15 respectively, and for a 50% change, they increased further to 1.78 and 1.35 respectively. The ecological state variables were also sensitive to increased catchment loads and depths. The modelled system switches from seagrass dominated to algal dominated at loads over 10?? the current loads, with increased plankton biomass and suspended solids shading the seagrass. The spatially resolved ecological model is run for a variety of open/closed cycles to assess the impact of various opening regimes on the model state variables. The results indicate that Smiths Lake is capable of assimilating its current nutrient loads without persistent phytoplankton blooms or a decrease in seagrass biomass. When catchment loads are increased by 10?? or the duration of the lake open/closed cycle is increased there is a corresponding increase in seagrass biomass. In contrast, small and large phytoplankton both increase in biomass as the duration of the open phase increases. Small and large phytoplankton growth is generally limited by phosphorus, and seagrass growth is limited by nitrogen under normal catchment loads. Due to the shallow depths and low phytoplankton biomass, seagrass only becomes light limited when the nutrient and suspended solids loads are increased 10??. This switch to light limitation only decreases the biomass for short periods.
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Long-wave wind effects on closed lakes, with special application to the Murray Mouth Lakes, South AustraliaWalsh, Patrick Joseph January 1974 (has links)
xi, 178 leaves : ill., maps, charts (some fold.) ; 28 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.1975)--University of Adelaide, Dept. of Applied Mathematics, 1975
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An introductory look at the fishes of the Opossum Creek / Camp Hydaway Lake System and the effects of an herbicide on the Lake's aquatic plantsDeweber, Jefferson T. January 2007 (has links)
Thesis (Honors)--Liberty University Honors Program, 2007.
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Phosphorus cycling in Maine lakes: a sedimentary analysis /Coolidge, Kyle Marvin, January 2004 (has links)
Thesis (M.S.) in Civil Engineering--University of Maine, 2004. / Includes vita. Includes bibliographical references (leaves 50-56).
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Mechanisms controlling long-term changes in periphytic diatom community structure /Olson, Olaf Gerald, January 1998 (has links)
Thesis (Ph. D.)--Lehigh University, 1998. / Includes vita. Bibliography: leaves 98-109.
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Great Lakes rural cultureHollingsworth, D. Richard. January 2000 (has links)
Thesis (D.Min.)--Austin Presbyterian Theological Seminary, 2000. / Includes bibliographical refereces (leaves 261-272).
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Seasonal variations in the forms of nitrogen found in lake waters and their relation to certain types of bacteria Part I. The proteolytic action of Bacillus granulobacter Pectinovorum and its effect on the hydrogen-ion concentration. Part II. The forms of nitrogen found in certain lake waters. Part III. The occurrence of amino acids and other organic nitrogen compounds in lake water. Part IV. Seasonal variations in the ammonia and nitrate content of lake waters and their relation to certain types of bacteria /Domogalla, Bernhard January 1900 (has links)
Presented as Thesis (Ph. D.)--University of Wisconsin--Madison, 1925. / Added collective thesis title page. Part I. ("By W.H. Peterson, E.B. Fred and B.P. Domogalla") reprinted from Journal of the American Chemical Society, vol. XLVI, no. 9 (Sep. 1924), p. [2086]-2090. Parts II. ("[by] B.P. Domogalla, C. Juday, and W.H. Peterson") and III. ("[by] W.H. Peterson, E.B. Fred and B.P. Domogalla") reprinted from Journal of biological chemistry, vol. LXIII, no. 2 (Mar. 1925), p. 269-295. Part IV. ("[by] B.P. Domogalla, E.B. Fred and W.H. Peterson") reprinted from Journal of the American Water Works Association, vol. 15, no. 4 (Apr. 1926), p. 369-385. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
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