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Dissertations / Theses on the topic 'Sewage disposal in rivers, lakes'

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1

O'Hearn, Rebecca Jones John R. "Nutrients, chlorophyll and bacterial fecal indicators in coves and open water areas of Lake of the Ozarks, Missouri." Diss., Columbia, Mo. : University of Missouri--Columbia, 2009. http://hdl.handle.net/10355/6563.

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The entire thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file; a non-technical public abstract appears in the public.pdf file. Title from PDF of title page (University of Missouri--Columbia, viewed on November 19, 2009). Thesis advisor: Dr. John R. Jones. Includes bibliographical references.
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2

Li, Lin. "A semi-analytical self-similar solution of a bent-over jet in crossflow /." Hong Kong : University of Hong Kong, 1998. http://sunzi.lib.hku.hk/hkuto/record.jsp?B20353029.

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3

Li, Lin, and 李琳. "A semi-analytical self-similar solution of a bent-over jet in crossflow." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1998. http://hub.hku.hk/bib/B31221373.

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4

Esposito, David M. "Hydrogeochemistry of stream channel recharge of sewage effluent, northwest of Tucson, Arizona." Diss., The University of Arizona, 1993. http://hdl.handle.net/10150/191176.

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This investigation has documented the water quality impacts of stream channel recharge of sewage effluent northwest of Tucson and has evaluated the hydrogeochemical mechanisms potentially responsible for observed water quality changes. The evaluation was accomplished partly through construction of twelve monitor wells and implementation of a quarterly water quality monitoring program for surface water and groundwater. Constituents monitored included major inorganic chemical constituents, trace inorganics, trace metals, priority pollutants/trace organics and microbiological contaminants. ¹⁵N also proved useful in the study. The significance of a reducing zone immediately beneath the bed of the Santa Cruz River with respect to denitrification was documented. Findings of this investigation indicate that while sewage effluent is of poor quality with respect to drinking water standards, groundwater recharged by sewage effluent is of improved quality. Other findings include: * Nitrate in shallow groundwater near the Santa Cruz River in the Cortaro area appears to be primarily from stream channel recharge of sewage effluent; * Nitrate-N contents of effluent recharged groundwater averaged about 5 mg/1, well below the maximum contaminant level for drinking water of 10 mg/1, representing a 75 percent loss in total nitrogen during stream channel recharge of sewage effluent (assuming no mixing); * Both stream channel recharge of sewage effluent and agricultural deep percolation contribute to nitrate in shallow groundwater near the Santa Cruz River in the Marana area; * The reducing zone beneath the Santa Cruz River may be responsible for denitrification losses of up to 5 mg/1 of nitrate-N. This would explain approximately 30 percent of nitrogen losses, on average, between effluent and recharged groundwater; * The mechanisms of cation exchange and mixing with groundwater from other sources can explain the major changes in water quality between effluent and groundwater with respect to major inorganic chemical constituents; * Renovation of effluent with respect to coliform bacteria and enteric viruses content during recharge is not complete.
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5

Lacher, Laurel Jane 1964. "Recharge characteristics of an effluent dominated stream near Tucson, Arizona." Diss., The University of Arizona, 1996. http://hdl.handle.net/10150/191199.

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Almost 90% of the treated sewage effluent processed by the two treatment plants serving the greater Tucson area is available for passive recharge through the Santa Cruz River streambed north of Tucson. In the absence of any major disturbance of the effluent channel, the recharge capacity of the streambed materials decreases over time as microbial activity, and possibly suspended sediments settling out of solution, act to clog the surficial sediments under the effluent stream. Effluent stream transmission-loss measurements made over the period from November 1994 to August 1995 provided data used to determine the average vertical hydraulic conductivity of the low-flow channel in the study reach through simulations using the computer model known as KINEROS2. Saturated hydraulic conductivity (KSAT) served as the calibration parameter in the model. The appropriate KSAT value was chosen for each set of field data by matching the observed and simulated downstream hydrographs for the study reach. KSAT values were corrected for viscosity changes resulting from changing average daily surface water temperatures over the study period. Saturated hydraulic conductivity values for the effluent stream channel ranged from a maximum of 37 mm/hr in January, 1995, following several major winter storms, to a minimum of 11 mm/hr in August, 1995, after a nearly six-month interstorm period. The saturated hydraulic conductivity values decay exponentially with time after the last major winter storm. The mathematical model describing this decay may be used to estimate effluent recharge rates under similar future meteorological and climatological conditions.
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6

Muller, Matthew Justin. "Linking institutional and ecological provisions for wastewater treatment discharge in a rural municipality, Eastern Cape, South Africa." Thesis, Rhodes University, 2013. http://hdl.handle.net/10962/d1013048.

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The Green Drop Certification Programme, launched in 2008 alongside the Blue Drop Certification Programme, aims to provide the Department of Water Affairs with a national overview of how municipalities and their individual wastewater treatment works (WWTW) are complying with licence conditions set by the National Water Act (NWA) (No. 36 of 1998; DWAF 1998) and the Water Services Act (No. 108 of 1997; DWAF 1998). By publishing the results of each municipality’s performance, the programme aims to ensure continuous improvement in the wastewater treatment sector through public pressure. The programme has been identified by this project as a necessary linking tool between the NWA and the Water Services Act to ensure protection and sustainable use of South Africa’s natural water resources. It does this through assisting municipalities to improve their wastewater treatment operations which in theory will lead to discharged effluent that is compliant with discharge licence conditions. These discharge licences form part of the NWA’s enforcement tool of Source Directed Controls (SDC) which help a water resource meet the ecological goals set for it as part of Resource Directed Measures (RDM). The link between meeting the required SDC and achieving the RDM goals has never been empirically tested. This project aimed to determine the present ecological condition of the Uie River, a tributary of the Sundays River which the Sundays River Valley Municipality (SRVM) discharges its domestic effluent into. It then determined whether the SRVM’s WWTW was complying with the General Standard licence conditions and what the impact of the effluent on the river was through the analysis of monthly biomonitoring, water chemistry and habitat data. Lastly, the project examined the effectiveness of the Green Drop Certification Programme in bringing about change in the SRVM’s wastewater treatment sector, which previously achieved a Green Drop score of 5.6 percent. It wanted to examine the underlying assumption that a WWTW which improves its Green Drop score will be discharging a better quality effluent that will help a water resource meets the RDM goals set for it. The Kirkwood WWTW did not have a discharge licence at the time of assessment and was thus assessed under the General Standard licence conditions. It was found that the Kirkwood WWTW was not complying with the General Standard discharge licence conditions in the Uie River. This was having a negative impact on the river health, mainly through high concentrations of Total Inorganic Nitrogen (TIN-N), orthophosphate and turbidity. The SRVM should see an improvement in its Green Drop score for the Kirkwood WWTW. However, the municipality showed no implementation of necessary programmes. Implementation of these programmes would help the SRVM meet the General Standard licence conditions (part of SDC) which would help the Uie River meet the RDM goals set for it.
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7

De, Almeida Louise. "The effect of sewage effluent from De Beers marine diamond mining operations on the expression of cytochrome P450 (CYP1A) and vitellogenin (vtg)." Thesis, Rhodes University, 2013. http://hdl.handle.net/10962/d1009440.

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Sewage effluents disposed into the marine environment from De Beers Marine Namibia diamond mining vessels have the potential to cause endocrine disruptive effects in marine organisms. Endocrine disruption refers to the alteration of the normal functioning of the endocrine system and various chemicals have the ability to mimic hormones, effecting endogenous hormone synthesis, transport, receptor interaction and intracellular signaling. The potential endocrine disruptive effects, caused by the release of different types of sewage effluents into the ocean, on fish species is a concern due to the commercial importance of fish species found in the mining area e.g. hake, sole, horse mackerel. Increased awareness of marine environmental degradation due to the presence of chemical contaminants has resulted in research being done on early warning systems, in the form of biomarkers. Cytochrome P450 monooxygenase 1A (CYP1A) and vitellogenin (vtg) are important proteins found in fish liver and blood, that have been used as biomarkers for the detection of pollutants in fish. CYP1A is a subfamily of the P450 superfamily of enzymes and catalyzes the oxidation, hydrolysis and reduction of exogenous and endogenous compounds (phase I reactions) and thus has the capacity to regulate the metabolism of several organic contaminants. CYP1A expression is altered by exposure to planar xenobiotic compounds e.g. polyaromatic hydrocarbons. Vtg is an important precursor for egg yolk proteins and plays a role in the growth and development of an oocyte. Expression of this protein is altered upon exposure to estrogenic compounds. The aim of this project was to isolate CYP1A from fish liver by differential centrifugation and optimize conditions for the CYP1A-mediated ethoxyresorufin-Odeethylase (EROD) assay and western blot analysis (to assess CYP1A expression). Another aim of this study was to evaluate the potential effects of biologically disruptive chemicals from sewage effluents, discharged into the marine environment, on the expression of CYP1A in two species of hake, Merluccius capensis and M. paradoxus (Cape hake). CYP1A in Cape hake is approximately a 60 kDa protein and the highest EROD activity was detected in the microsomal fraction after differential centrifugation. Optimal EROD assay conditions were observed at pH 7.5, a temperature of 25 °C, 10 μl of sample and a reaction time of 30 seconds. Enzyme stability assays indicated a drastic decrease in enzyme activity after 30 seconds. The EROD assay was not NADPH dependent but was limited by NADPH supply, with an increase of 300% in EROD activity being observed with the addition of 0.1 M exogenous NADPH. The addition of dicumarol (40 μM), a phase II enzyme inhibitor, showed a 232% increase in EROD activity. This is because dicumarol inhibited enzymes with the capacity to metabolize the product (resorufin) of the EROD reaction. With regard to western blot analysis, the optimal primary (rabbit antifish CYP1A peptide) and secondary (anti-mouse/rabbit antibody-horseradish peroxidase conjugate (POD)) antibody dilutions were determined to be 1:1000 and 1:5000, respectively. The comparison of CYP1A expression in Cape hake samples from De Beers Marine mining area and reference sites showed higher EROD activity (16.29 ± 0.91 pmol/min) in fish samples from the mining area in comparison to the reference site (10.42 ± 2.65 pmol/min). Western blot analysis was in agreement with the EROD assay results and a higher CYP1A expression was observed in fish from the mining sites. The increased CYP1A expression observed in fish from the mining area is not definitively an indication of a pollutant effect in the environment, as several environmental and biological factors (e.g. photoperiod and age) must also be considered before reaching this conclusion. Another aim of this study was to purify vtg from Cape hake blood samples. Cape hake vtg was purified from fish plasma by selective precipitation with MgCl2 and EDTA. Precipitated sample was subjected to anion exchange chromatography using fast protein liquid chromatography (FPLC). Vtg eluted as two broad peaks and had a molecular weight above 200 kDa. SDS-PAGE analysis also resolved smaller molecular weight proteins below 70 kDa, which were thought to be vitellogenin cleavage proteins, lipovitellin and phosphovitins. Western blot analysis was performed; however, it did not produce any conclusive results. The purification of vtg enables further studies in characterizing this protein and developing assay aimed at detecting estrogenic pollutants in the marine environment
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8

Yau, Yick-yee Joyce. "Bacterial indicators for beach water quality /." Hong Kong : University of Hong Kong, 1999. http://sunzi.lib.hku.hk/hkuto/record.jsp?B21301554.

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9

Yau, Yick-yee Joyce, and 丘奕怡. "Bacterial indicators for beach water quality." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1999. http://hub.hku.hk/bib/B31254445.

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10

Gola, Nontutuzelo Pearl. "The value of locally isolated freshwater micro-algae in toxicity testing for water resource management in South Africa." Thesis, Rhodes University, 2015. http://hdl.handle.net/10962/d1017873.

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The ecological position of micro-algae at the base of the aquatic food web makes them critical components of aquatic ecosystems. Their short generation time also makes them useful biological indicators because they respond quickly to changes in environmental condition, enabling timely identification and assessment of water quality changes. The inclusion of micro-algae as indicators in water resource regulation and management in South Africa has started recently, their more extensive use in biomonitoring and ecotoxicology programmes for water resource management would contribute to the South African policy if water resource protection. The standard algal growth inhibition assay with the species Pseudokirchneriella subcapitata is currently used for monitoring toxicity of in-stream and industrial wastewater discharges to freshwater micro-algae. The relevance of the data generated by standard toxicity bioassays has been questioned, since micro-algae in particular are extremely variable in their sensitivity to a range of contaminants and these standard species used may not occur in the local aquatic environment. As a result, international regulatory agencies, have recommended algal growth inhibition tests be changed from a single standard species to tests with a number of species. One recommendation, in addition to the use of standard toxicity tests, is the use of species isolated from the local environment which may be more relevant for assessing site specific impacts. This study investigated the value and application of locally isolated South African freshwater micro-algae in toxicity tests for water resource management and was carried out in three phases. The first phase involved isolating micro-algae from South African aquatic resources. Micro-algae suitable for toxicity testing were identified and selected using as set of criteria. Three (Scenedesmus bicaudatus, Chlorella sorokiniana and Chlorella vulgaris) out of eight successfully isolated species satisfied the prescribed selection criteria and these were selected as potential toxicity test species. The second phase focused on refining and adapting the existing algal toxicity test protocol (the algal growth inhibition assay) for use on the locally isolated algal species. The refinement of the test protocol was achieved by exposing the locally isolated species to reference toxicants in order to assess and compare their growth and sensitivity to the toxicants under the prescribed toxicity test conditions with that of the standard toxicity test species (Pseudokirchneriella subcapitata) and a commercial laboratory species (Chlorella protothecoides). During this phase, one of the three local species (Scenedesmus bicaudatus) was eliminated as a potential toxicity test species due to inconsistent growth. The third phase of the study involved assessing the sensitivity of the two remaining species (C. vulgaris and C. sorokiniana) to a range of toxicants (reference toxicants, salts, effluents and a herbicide) and comparing it to that of the standard toxicity test species P. subcapitata and C. protothecoides. The toxicants were selected based on their relative importance in the South African context, as well as the practicality of using these local micro-algae to routinely determine the impact of these toxicants on local aquatic resources. The growth of the four micro-algae was stimulated by the selected effluents. The standard toxicity test species P. subcapitata was ranked the most sensitive and of the four species to two reference toxicants and two inorganic salts. Chlorella sorokiniana was ranked the most sensitive of the three Chlorella species to two reference toxicants and two inorganic salts. The herbicide stimulated the growth of C. vulgaris while inhibiting the growth of the other species. Pseudokirchneriela subcapitata and C. sorokiniana showed high intra-specific variability in growth, which made it difficult to determine the effective concentrations of the herbicide and therefore compare the sensitivity of the species. This varied response of micro-algal species to toxicants may result in the biodiversity shifts in aquatic ecosystems, and also supports the recommendation of using a battery of different species to support more informed decisions in water resource management.
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11

Sauveur, Stephen Charles. "Estimation of phosphorus contributed to lakes from on-site sewage disposal systems." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape8/PQDD_0021/MQ48287.pdf.

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12

Tse, Kiu-chung. "Estimation of submarine groundwater discharge into Tolo Harbour." Click to view the E-thesis via HKUTO, 2006. http://sunzi.lib.hku.hk/hkuto/record/B38230926.

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13

Rutherford, Jasmine Lee. "The role of geology, geomorphology, climate and vegetation, in controlling spatial and temporal changes in groundwater discharge from weathered crystalline basement aquifers in southwestern Australia /." Connect to this title, 2005. http://theses.library.uwa.edu.au/adt-WU2006.0006.

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Tse, Kiu-chung, and 謝喬中. "Estimation of submarine groundwater discharge into Tolo Harbour." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2006. http://hub.hku.hk/bib/B38230926.

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15

Loveless, Alicia Maree. "The spatial, temporal and biogeochemical dynamics of submarine groundwater discharge in a semi-enclosed embayment /." Connect to this title, 2006. http://theses.library.uwa.edu.au/adt-WU2007.0113.

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16

Soltis, Jeffrey J. "Stakeholder participation in watershed permitting in the Powder River Basin of Wyoming satisfaction, success, discourse, and knowledge /." Laramie, Wyo. : University of Wyoming, 2008. http://proquest.umi.com/pqdweb?did=1686179941&sid=1&Fmt=2&clientId=18949&RQT=309&VName=PQD.

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17

Randall, William O. "The Effects of a phosphate detergent ban on a biological nutrient removal plant and anaerobic digester /." Thesis, This resource online, 1990. http://scholar.lib.vt.edu/theses/available/etd-03122009-040637/.

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Lee, Chun-ming, and 李進銘. "Estimation of submarine groundwater discharge and nutrient loading of Tolo Harbour." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2012. http://hub.hku.hk/bib/B48330206.

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Tolo Harbour is naturally eutrophic with frequent algal blooms in the past. Water quality of the Harbour has been improved in past 20 years but the phytoplankton density is still high compared to other waters in Hong Kong. This study aimed to quantify submarine groundwater discharge (SGD) to Tolo Harbour and to show the important role of SGD in terms of nutrient loading with ecological effect. SGD was determined by one of the natural geochemical tracers, 226Ra. Mass balance of 226Ra was applied to quantify SGD and SGD was estimated to be 8.28 × 106 m3 d-1. A large portion of the SGD was recirculated seawater while the freshwater component of SGD, or submarine fresh groundwater discharge (SFGD), was only a small portion of that. SFGD was estimated to be 2.31 ×105 m3 d-1 using water balance. The flushing time of Tolo Harbour was estimated to be 77.9 d by using SFGD as one of the fresh water input components. Different nutrients including NH3—N, NO2—N, NO3—N, PO43-—P, SiO2—Si and dissolved inorganic nitrogen (DIN) were applied to nutrient mass balance analyses. The mass balance is based on non-point sources which include aerosol deposition (dry deposition), rainfall (wet deposition), diffusion from sediment, river, SGD and tidal exchange. Removal of nutrients was determined once all the non-point sources were estimated. SGD is the major source which contributes more than 88 % for different nutrients. Other sources contribute less than 10 % individually. The total nutrient loads of DIN, PO43-–P and SiO2—Si are 8.33 ×105, 1.03 ×104 and 1.28 ×106 mol d-1 respectively. The removals of DIN, PO43-–P and SiO2—Si are 6.87 ×105, 5.10 × 103 and 1.28 ×106 mol d-1 respectively. Assume the removal of nutrients was only due to consumption of phytoplankton, primary productivity was estimated to be 1.16g C m-2 d-1. Limitations of this study were about the determination of atmospheric depositions and diffusion from sediment. However, the contribution of nutrient loading from these sources was insignificant compared with SGD. Even if SGD is replaced by SFGD for the nutrient loading estimation, it is still the major contributor among all other non-point sources. In spite of the limitations, the important role of SGD in terms of nutrient loading is evident. Groundwater quality should be monitored and controlled as it has significant ecological impact to the Harbour.
published_or_final_version
Earth Sciences
Master
Master of Philosophy
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19

Songkiatisak, Preeyaporn. "A simulation model for triclosan concentrations in the North and Middle Rivers, Virginia /." Full-text of dissertation on the Internet (1.47 MB), 2009. http://www.lib.jmu.edu/general/etd/2009/Masters/Songkiatisak_Preeyaporn/songkipx_masters_11-20-2009.pdf.

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Chan, Yi-kei, and 陳伊祺. "Nutrient input of Tolo Harbour by river, atmospheric deposition and submarine groundwater discharge." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2011. http://hub.hku.hk/bib/B46732718.

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Loveless, Alicia Maree. "The spatial, temporal and biogeochemical dynamics of submarine groundwater discharge in a semi-enclosed embayment." University of Western Australia. School of Environmental Systems Engineering, 2007. http://theses.library.uwa.edu.au/adt-WU2007.0113.

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[Truncated abstract] It has become widely apparent throughout the world that the discharge of nitrogen contaminated groundwater is reducing surface water quality of marine coastal waters, and is subsequently contributing to the decline of benthic habitats such as seagrasses. A process-based understanding of submarine groundwater discharge (SGD) has lagged behind these impacts, and this lack of understanding is addressed by this thesis. This thesis, of the spatial and temporal complexity of SGD, has uncovered and answered questions regarding the sources, fate and transport of SGD in a complex coastal discharge environment. Radium isotope techniques, groundwater biogeochemical investigations and HAMSOM surface water modelling have identified the magnitude, transport and fate of SGD in Cockburn Sound, a semienclosed embayment in Western Australia. A temporal periodicity that encompassed end-of-winter, early-summer, late-summer and mid-winter regimes of hydrology and oceanography, was employed in field studies that spanned the years 2003, 2004 and 2005. ... The fate of the groundwater in the semi-enclosed embayment was investigated using knowledge of surface water currents. Localised regions of high groundwater influence were identified in the surface waters of the embayment, and through the application of a 3-dimensional hydrodynamic model (HAMSOM) it was discovered that, despite similar total volume residence times, variation in the surface flow regime resulted in very different fates for groundwater discharged to the embayment. For three of the four investigated seasonal regimes, groundwater discharged at the shoreline was shown to be rapidly exported out of the embayment (within approximately 1-3 days). During mid-winter very different wind and current regimes existed, resulting in the lateral transport of shoreline groundwater across the embayment, presenting potential for nutrient recirculation within the system for longer time periods (10+ days). Lateral transport of groundwater during mid-winter from the limestone region of the coastline, may contribute to peaks in phytoplankton biomass that have been reported to occur at this time. The investigations into spatial, temporal and biogeochemical dynamics of SGD provided for further dissertation of the processes that affect these dynamics, at a scale that was relevant to marine embayments, coastal aquifers and the coastal ecosystem. It is hoped that this thesis will contribute to a better understanding of the inputs, dynamics and impacts of SGD on coastal ecosystems and lead to improved management strategies for coastal zones.
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Rutherford, Jasmine Lee. "The role of geology, geomorphology, climate and vegetation, in controlling spatial and temporal changes in groundwater discharge from weathered crystalline basement aquifers in southwestern Australia." University of Western Australia. School of Earth and Geographical Sciences, 2006. http://theses.library.uwa.edu.au/adt-WU2006.0006.

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[Truncated abstract] The Collie River drainage basin is an important water resource catchment in southwestern Australia. Salinisation of a major water supply within the catchment, the Wellington Reservoir, has arisen due to changes in the water and salt balance in response to land clearing over saprolite aquifers. Paired catchment studies, the Collie Experimental Catchments (CECs), established in the early 1970’s in high and low rainfall areas increased our understanding of water and salt (predominantly chloride) movement in these aquifers through the collection and analysis of high resolution spatio-temporal data. However, the conceptual models developed from this work take little account of landscape heterogeneity, and this has caused problems in subsequent modelling studies, where success in calibrating stream flow has been countered by difficulties in predicting salt loads. The challenge remains to better describe variability in the Collie landscape and understand the influence of climate, vegetation, geology and geomorphology on observed water and salt fluxes. The release of salt from the lower saprolite aquifer and the role of the surficial aquifer in buffering groundwater discharge were investigated. The acquisition, analysis and interpretation of new regolith and geophysical data in 2001-2003 from the CECs, together with data from a high resolution digital elevation model, and existing drilling information, were used to construct a geologicalgeomorphological compartment framework, to observe changes in aquifer behaviour ... Significant differences in the salt flux from compartments have been noted at a range of scales, with implications for both water resource and land management. The approach developed to identify compartments and assess their efficiency could be simplified, using catchment critical parameters determined from geological and geomorphological characteristics. As a consequence, the implementation of a compartment framework in catchments with saprolite aquifers should allow for more informed decisions to be made in the selection of sites for revegetation strategies or the development of engineering works. This is particularly important in the Collie Catchment where reclamation scenarios are currently being discussed. Consideration of the catchment as a compartmentalised system would help manage salt loads in the Collie River and return the Wellington Reservoir to a functional water resource.
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Lacher, Laurel Jane. "Recharge characteristics of an effluent dominated stream near Tucson, Arizona." 1996. http://etd.library.arizona.edu/etd/GetFileServlet?file=file:///data1/pdf/etd/azu_e9791_1996_253_sip1_w.pdf&type=application/pdf.

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Seanego, Koena Gloria. "Ecological status of the Sand River after the discharge of sewage effluent from the Polokwane and Seshego wastewater treatment works." Thesis, 2014. http://hdl.handle.net/10386/1329.

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Thesis (M.Sc. (Aquaculture)) -- University of Limpopo, 2014
Population growth in urban areas is putting pressure on sewage treatment plants. The improper treatment of sewage entering the aquatic ecosystems causes deterioration of the water quality of the receiving water body. The effect of sewage effluent on the Sand River was assessed. Eight sampling sites were selected, site 1 and 2 were upstream of the of the sewage treatment plant along the urbanised area of Polokwane, whilst sites 3, 4, 5, 6, 7 and 8 were downstream. The physicochemical parameters and coliform counts in the water samples were determined. Macroinvertebrate abundances and diversity (H') was determined at the different sites during the dry and rainy season. The water quality status of the Sand River with respect to the South African scoring system (SASS) scores and average score per taxon (ASPT) was determined. A linear regression was performed to test the correlation of the SASS scores with abundance and H'. Heavy metal concentrations in water, sediment, grass (Ishaemum fasciculatum) and fish (Oreochromis mossambicus) at the sites were evaluated. The suitability of the Sand River and surrounding borehole water for irrigation was also determined. Hierarchical average linkage cluster analysis produced two clusters, grouping two sites above the sewage treatment works and six sites downstream of the sewage effluent discharge point. Principal component analysis (PCA) identified total nitrogen, total phosphorus, conductivity and salinity as the major factors contributing to the variability of the Sand River water quality. These factors are strongly associated with the downstream sites. Canonical correspondence analysis (CCA) indicated that Chironomidae family was found on the nitrogen gradient during the dry season. However during the rainy season, Chironomidae was found in the centre of the ordination which indicated that it was ubiquitous. Escherichia coli levels (1463.73 counts/100ml) in the maturation ponds of Polokwane wastewater treatment works could potentially lead to contamination of the Polokwane aquifer. High diversity was recorded at the sites before discharge and the sites further downstream. There was significant correlation (P<0.05) between the SASS scores and macroinvertebrate diversity during the dry season (R2=0.69) and the rainy season (R2=0.77). Fish samples had significantly higher (P<0.05) iron and copper concentrations, while the vi sediment had significantly higher lead concentration (P>0.05). The United States salinity laboratory (USSL) diagram indicated that the sodium hazard (SAR) and alkalinity hazard (conductivity) was low and the Sand River and borehole water was suitable for irrigation. The residual sodium carbonate (RSC) was below 1.24 meq/l, also indicating that both the Sand River and borehole water is still suitable for irrigation. The total phosphorus concentrations fluctuated across the different site. Total nitrogen concentrations showed a gradual decrease downstream from the point of discharge. The coliform levels also showed a gradual decrease downstream. This shows that the river still has a good self-purification capacity.
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West, D. W. "Responses of wild freshwater fish to anthropogenic stressors in the Waikato River of New Zealand." 2007. http://adt.waikato.ac.nz/public/adt-uow20070828.145414/index.html.

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26

Ojijo, Vincent Omondi. "Treatment of wastewater containing Melanoidin through simultaneous adsorption and biodegradation processes." 2010. http://encore.tut.ac.za/iii/cpro/DigitalItemViewPage.external?sp=1000476.

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M. Tech. Engineering : Chemical.
Evaluates the applicability of adsorption, biodegradation and hybrid adsorption and biodegradation system in treatment of wastewater containing melanoidin.Treatment of wastewater containing melanoidin through SAB process in fluidized bed bioreactor results in the best performance index as compared to adsorption and biodegradation processes undertaken singly. The synergies realized are more pronounced in fluidized bed bioreactor than in stirred tank system.
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Otieno, Dennis Ouma. "Treatment of tea industry effluents using a combined adsorption and advanced oxidation process." 2014. http://encore.tut.ac.za/iii/cpro/DigitalItemViewPage.external?sp=1001708.

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Abstract:
M. Tech. Chemical Engineering.
Discusses the general objective of this research is to study the application of a combined advanced oxidation and adsorption process, with a view to developing a novel technique for the treatment of tea industry effluents prior to discharge into receiving water bodies. The specific objectives of the research are: a) To tailor natural zeolite physico-chemical properties in attempt to enhance its adsorptive performance ; b) To evaluate the decolourization efficiency of functionalized zeolite in tea industry effluent treatment. c) To evaluate the effect of the following operational parameters: pH, initial concentration,temperature and the sorbent mass, on the removal of colour in tea industry effluent. d) To apply adsorption and advanced oxidation independently and to combine the two into one process.
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