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Monitoring the effects of offshore aquaculture on water quality in the Red SeaDunne, Aislinn 06 1900 (has links)
The Saudi Arabian government has announced an economic development plan (Vision 2030) to invest in a range of industries across the Kingdom, one of which is the development of aquaculture. In the face of a likely increase in Red Sea fish farming, we investigated the impacts of offshore fish farms on the coastal water quality of the Red Sea by a) measuring the environmental impacts of an operational Red Sea fish farm, and b) testing whether an existing aquaculture modeling software can be used as a meaningful planning tool in the development of Red Sea aquaculture. Water quality parameters such as dissolved oxygen, nutrients, particulate matter, chlorophyll, ammonium, and bacterial abundance were measured seasonally over the course of a year around an offshore fish farm along the south-central coast of Saudi Arabia to determine the impacts of fish farm effluent on the surrounding waters. Bacteria, phosphate, inorganic nitrogen, and suspended particulate matter showed patterns of enrichment close to the fish farm. Additionally, dissolved oxygen has slightly lower concentrations close to and down current from the fish farms. Benthic sediments from a nearby coral reef were also assessed for organic enrichment, but concentrations of total organic carbon and total nitrogen were not significantly different from those at an offshore reef. The data from these sampling efforts were then used as input parameters for an aquaculture modeling software (AquaModel.net), however many of the input parameters required to run the model were unavailable and meaningful conclusions could not be drawn from the results. Through field studies and modeling, we assessed the current impact of a Red Sea fish farm on water quality with the goal of predicting the potential impacts of future offshore aquaculture development in Saudi Arabia.
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Catchment diagnostic framework for the Klip River catchment, Vaal Barrage, October 1998 - September 1999.Davidson, Celene 11 August 2003 (has links)
This research report is a completed Catchment Diagnostic Framework (CDF) for the Klip
River catchment (Johannesburg) for the period October 1998 to September 1999.
The framework consists of a catchment description and a diagnostic index which provide
a simple and representative view of the catchment and its characteristics and assist in
identifying problem areas.
GIS maps, graphs and tables are used to provide a background of the catchment. The
Diagnostic Index is based on a set of Indicators that are calculated and then scored
according to a rating system allowing for the calculation of an overall value for the
catchment. The indicators and description cover resource conditions, socioeconomics,
water quantity, water quality and management.
Using this CDF it was found that the Klip River catchment is highly altered due to
mining, urban, industrial and agricultural development. All of these have impacts on the
beneficial use of the Klip River itself and on the downstream users of the Vaal Barrage. / AC 2016
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Assessment of the Impacts of a Biofiltration Best Management Practice (BMP) and Associated Groundwater Flow on Water QualityTupper, Jacquelyn E 30 April 2015 (has links)
Stormwater runoff from urbanized areas can have detrimental impacts on groundwater and surface water supplies by mobilizing contaminants such as bacteria and nutrients from surrounding areas. Best Management Practices (BMPs) are commonly designed to mitigate these impacts, but the processes governing the effectiveness of these BMPs are often not well understood. Biofiltration BMPs, which include storage, sediment removal, and infiltration processes, are particularly challenging to quantify.
This research involved an investigation of the processes associated with a biofiltration BMP located in West Boylston, MA adjacent to the Wachusett Reservoir. The basin treats runoff from an 8-acre watershed with two roadways (Routes 12 and 110) and surrounding residential and commercial land uses. Water exits the basin by either seepage directly to groundwater or by seepage through a two-foot filtration bed to an outfall pipe on one side of the basin. A field sampling program was conducted in collaboration with the Massachusetts Department of Conservation and Recreation to characterize the various flow paths of contaminants upstream, within, and downstream of the biofiltration facility. The program included collection of volumetric flow information, field parameters (dissolved oxygen, specific conductance, pH, and temperature), and water quality samples. Samples were tested for alkalinity, bacteria, dissolved organic carbon, nutrients, additional anions and cations, and suspended sediments. Stormwater samples were collected for storm events that included substantial rainfall and illustrated seasonal variability. A set of seven monitoring wells installed for this project provided information on groundwater flow and quality at the site.
The field program provided quantitative data on the flows and transformations that occur within and in the groundwater downstream of the biofiltration basin. The results demonstrated that stormwater infiltration to groundwater is an important component to consider for BMP design. The flow path through the outfall was effective in removing sediments, but was found to have limited capacity for water quality treatment, since only small changes in stormwater quality occurred between the culvert inflow, basin, and outfall samples. However, analysis of the flow data showed that infiltration to groundwater was comparable to discharge through the outfall. Furthermore, the signatures of stormwater infiltration could still be seen in the wells, indicating that the infiltration from the stormwater basin can impact groundwater quality. The groundwater pathway was found to impact the chemistry of the constituents, and was particularly effective in removing bacteria and phosphorus. The results demonstrate the value of groundwater recharge as a component of BMP design, and provide a basis for a number of specific design recommendations related to biofiltration basins.
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Cultivation of invasive zebra mussels (Dreissena polymorpha) for the improvement of reservoir water qualityMcLaughlan, Claire January 2015 (has links)
No description available.
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Hidrogeoquímica do aquífero Adamantina na área urbana do município de Bauru/SP /Canato, Helena de Mello. January 2014 (has links)
Orientador: Fabiano Tomazini da Conceição / Co-orientador: Jorge Hamada / Banca: Rodrigo Braga Moruzzi / Banca: Guilhermo Rafael Beltran Navarro / Resumo: Neste trabalho buscou-se avaliar as influências naturais e antrópicas na qualidade da água subterrânea na área urbana de Bauru, interior do Estado de São Paulo. Para tal, foram selecionados 24 pontos de amostragem de águas subterrâneas no Aquífero Adamantina, Sistema Aquífero Bauru, analisando-se os seguintes parâmetros: condutividade elétrica, temperatura, pH, HCO3, PO42-, Cl, F, N-No3, Ca2+, Na, K+, Mg2+, Si4+, Fe3+ e Al3+. Os resultados indicaram que as águas subterrâneas na área urbana de Bauru possuem pH ligeiramente ácido e baixa condutividade, com sua composição iônica apresentado baixa concentração de cátions e ânions, sendo elas classificadas como moles ou moderadamente duras e biocarbonatadas cálcicas. As fontes naturais de elementos/compostos podem ser atribuídas a dissolução dos carbonatos, durante o processo de interação água/rocha, controlando o pH, alcalinidade, condutividade elétrica e hidrólise dos demais minerais constituintes das rochas sedimentares da Formação Adamantina, com exeção do quartzo. As elevadas concentrações N-NO-3 encontradas em alguns poços de abastecimento público na área urbana de Bauru são originadas devido às atividades antrópicas, oriundas do esgotamento sanitário / Abstract: This work evaluated the natural and anthropogenic influences in the quality of groundwater in the urban area of Bauru, São Paulo State. Twenty four sampling points were established in the Adamantina Aquifer, Bauru Aquifer System, analyzing the following parameters: electrical conductivity, temperature, pH, HCO3, PO42-, Cl, F, N-No3, Ca2+, Na, K+, Mg2+, Si4+, Fe3+ e Al3+. The results indicated that the groundwaters in the urban area of Bauru posses pH slightly acid and low conductivity, with the ionic composition presents low cations and anions concentration, being they classified as soft water and calcium-bicarbonated. Natural sources of elements/compounds can be attributed to the dissolution of carbonates during the water/rock interaction, controlling pH, alkalinity, electrical conductivity and hydrolysis of other mineral constituents of sedimentary rocks from Adamantina Formation, with the exception of quartz. High concentration of N-NO3 found in some public supply wells in urban Bauru originated due to sewage / Mestre
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Reclamation of wastewater for polyculture of freshwater fishLiang, Yan 01 January 1997 (has links)
No description available.
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Optimal regional water quality management by multilevel approach and the discrete maximim principlePaidy, Sudhakar Reddy January 2011 (has links)
Digitized by Kansas Correctional Industries
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Development of a hydrologic and water quality model of Cedar CreekVecchi, Anthony 01 May 2017 (has links)
The hypoxic zone in the Gulf of Mexico is a symptom of a greater problem of nutrient loss to streams across the American Midwest. The United States Environmental Protection Agency (EPA) has responded to the problem by requiring states along the Mississippi River to develop nutrient reduction strategies and implement practices that reduce nutrient loss. The state of Iowa developed their strategy and formed the Iowa Nutrient Research Center (INRC) to study the most effective conservation practices and policies. This thesis is conducted as part of the INRC and is focused on the development of a hydrologic and water quality model of the Cedar Creek watershed in southeastern Iowa.
The Cedar Creek hydrologic and water quality model was created using MIKE SHE, a coupled surface/subsurface modeling software. The model was calibrated using real-time streamflow and water quality measurements taken within the watershed. Several water quality scenarios were tested in order to determine the most effective ways to simulate nitrate concentration within the MIKE SHE framework. The results of this thesis will guide future hydrologic and water quality modeling in agricultural watersheds and serve as a demonstration of the ways to simulate nutrient transport within the landscape.
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In-stream nitrogen processing and dilution in an agricultural stream networkPrior, Kara 01 May 2015 (has links)
The interaction of agricultural fertilizer application and a drought-to-flood transition in 2012-2013 set up conditions for a watershed-scale experiment on nutrient dynamics. The region-wide drought in 2012 left surface soils disconnected from stream networks and restricted nutrient use by crops, resulting in an unusually large nitrogen pool stored in the soil column through the winter. The wet conditions in the Midwest in spring of 2013 mobilized the unused fertilizer from the landscape into the stream network. A six-week period of extremely high in-stream nutrient concentrations followed. This study analyzes results of three synoptic sampling campaigns in the Iowa-Cedar River Basin in 2013 to quantify patterns in nitrogen dynamics. I estimate nutrient spiraling metrics by interpreting the fertilizer mobilization from the landscape to the stream as a constant rate nutrient addition at the scale of the entire watershed—a vital scale on which to understand these processes, but for which costs and logistics of standard experiments are prohibitive. Results of this study compare patterns in dilution and uptake across spatial and temporal scales, and bound feasible explanations for hydrologic and reactive function in each reach of the network.
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Microbial populations as indicators of river 'health'Driessen, Jennifer Petronella, 1973- January 2000 (has links)
Abstract not available
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