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The characteristics, behaviour and heterogeneous chemical reactivity of estuarine suspended particlesBale, Anthony John January 1987 (has links)
No description available.
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An investigation into the heavy metals, sediment and vegetation of a Mersey Estuary salt marshJemmett, Alan William Lancaster January 1991 (has links)
No description available.
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Sedimentation in small active-margin estuaries of the northwestern United StatesPeterson, Curt D. 27 May 1983 (has links)
Graduation date: 1984
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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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Assessment of the Rhode Island coastal lagoon ecosystem /Ford, Kathryn Hale. January 2003 (has links)
Thesis (Ph. D.)--University of Rhode Island, 2003. / Typescript. Includes bibliographical references (leaves 178-187.
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Estuarine sediment nutrient exchange : the importance of physical transport mechanisms and benthic micro-communities /Reay, William Glendon. January 1992 (has links)
Thesis (Ph. D.)--Virginia Polytechnic Institute and State University, 1992. / Vita. Abstract. Includes bibliographical references (leaves 207-235). Also available via the Internet.
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Diffusion in a tidal estuaryBanks, Robert B. January 1952 (has links)
Thesis (doctoral)--Imperial College of Science and Technology, 1952. / Includes bibliographical references (leaves 73-74).
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Net ecosystem metabolism in Texas shallow water estuaries an indicator of freshwater inflow effects, scales of variability, and changes due to climate change and watershed development /Russell, Marc James, January 1900 (has links) (PDF)
Thesis (Ph. D.)--University of Texas at Austin, 2005. / Vita. Includes bibliographical references.
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Organic carbon in the subaqueous soils of a mesotidal Maine estuary: an investigation of quantity and source /Jespersen, Jennifer L., January 2006 (has links) (PDF)
Thesis (M.S.) in Ecology and Environmental Science--University of Maine, 2006. / Includes vita. Includes bibliographical references (leaves 73-94).
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Organic Carbon in the Subaqueous Soils of a Mesotidal Maine Estuary: An Investigation of Quantity and SourceJespersen, Jennifer L. January 2006 (has links) (PDF)
No description available.
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