One of the most essential resources for life on our planet is water. A concern for water resource sustainability has shifted towards the sustainable development of clean water body resource (SWDF, 2009). Data for the Vaal River water chemistry is in abundance. However, research on the historic natural conditions influencing the inorganic water quality, is not as extensive. Inorganic data was obtained from the Department of Water Affairs, for the period 1972 to 2011, for identified monitoring stations along the Vaal River. Water quality was evaluated using various geochemical techniques to analyse the data. The results of the study indicate that the water chemistry of the Vaal River is controlled by: 1. Chemical weathering of siliceous sediment, intrusive igneous rocks and metamorphic rocks (Na+, K+, Mg2+, Ca2+ and (HCO3)-). 2. Anthropogenic influences increasing the sulphate (SO4) concentration There is no major increase in ion concentrations for the stations. However the concentrations of bicarbonate (HCO3)- and SO4 change as it progresses downstream from the first upstream station to the last downstream station. Based on the chemical characterisation, three groups have been identified. (1) Group 1 stations appear to suggest a higher influence in chemical weathering than the group 2 stations. (2) Group 2 stations appear to suggest a greater influence from SO4. (3) Group 3 stations appear to suggest an influence from both the bicarbonate and the SO4 influences. Geographically the chemical weathering is an indication of the three different groups with strong anthropogenic influences in the middle group. The water chemistry for the Vaal River is controlled by two processes, namely chemical weathering and anthropogenic influences. The prominent indication of the difference in these two influences can be seen between group 1 and group 2. A secondary conclusion indicates that a total dissolved solid (TDS) alone is not an accurate representation of anthropogenic influence (or poor water quality) on inorganic water quality of the Vaal River. The natural weathering or geological influences appears to play a more dominant role in certain sections or catchments with lower contributions from anthropogenic influences. / MSc (Environmental Sciences), North-West University, Potchefstroom Campus, 2015

Masters of Science / Department of Agricultural Economics / Hikaru H. Peterson / Concerns about environmental degradation due to agriculture have gained importance as it is associated with soil erosion, health hazards, and ground water pollution. Environment-friendly land use practices have been developed to gain a wide range of environmental benefits including reduced soil erosion, reduced nutrient runoff from crop and livestock facilities, increased biodiversity preservation efforts, and restoration of wetlands and other native ecosystems. No-till is one such practice where soil erosion, nutrient runoff and environmental degradation can be reduced to a certain extent. This study evaluated the factors affecting the adoption of tillage systems in Kansas. A survey was conducted with a total of 135 participants from four different locations in the state of Kansas between August 2006 and January 2007. The adoption process was modeled as a two-step econometric models consisting of perception and adoption equations to estimate the impacts of demographic variables and farmers’ familiarity with and participation in certain conservation programs. The results for the perception models showed that the farm operators’ perceptions regarding whether BPM installation and management is unfair to producers or not and whether environmental legislation is often unfair to producers do not vary systematically across farm size, producers’ familiarity and participation in conservation programs, or other demographics considered in the study. On the other hand, their perceptions regarding how polluted their water supplies varied by their thoughts on relative profitability across various tillage practices, their primary occupation, and their familiarity with conservation programs. Specifically, the results suggested that those who regarded no-till practices to be more profitable than other tillage practices or whose primary occupation was farming-related tended to believe that ground water was not polluted, and those who were less familiar with available conservation programs tended to believe that surface waters were not polluted. The adoption model results suggested that farmers with greater operating acreage, those who perceived that no-till was more profitable than other tillage systems, and those with greater familiarity with and participation in existing conservation programs were more likely to adopt more conservation tillage systems, all else equal. Further, perceptions of fairness of environmental regulations or the level of pollution did not impact the tillage choices.

Thesis (M. Tech.) -- Central University of Technology, Free State, 2007 / In South Africa, water is a scarce resource and it has become very important to manage this resource effectively. The State developed a regulating framework, under the hospice of the Minister of Water Affairs and Forestry, which protects the country‟s water resources from over-exploitation by ensuring that it is protected, used, developed, conserved, and managed, in a sustainable and equitable manner. The laws and policies governing the use of water resources are contained in the National Water Act (South Africa, 1998), the National Water Policy (South Africa, 1997a), the National Water Resource Strategy, and the Water Services Act (South Africa, 1997b). In addition some water-related functions were transferred to Catchment Management Agencies and Water Users‟ Associations, and it is their task to ensure that the strategies, laws and policies are implemented. Effective water management can only be performed by making use of hydroinformatics which assists with simulations and estimations. As a result input data will be collected, added to a Relational Database Management System and output results generated. A Geographic Information System with the support of a geodatabase will allow users to store spatial and temporal data. The research project investigated different water-related data models (ArcHydro, Hydstra, GML, HYMOS, and WinHSPF), as well as hydrological modelling frameworks (BASINS, OMS, OpenMI, SPATSIM, and TIME) to determine whether they were adequate to assist with the decision making of water-related activities. It was found that these data models and hydrological modelling frameworks did not allow users to add new datasets to their existing data structures and in many cases only had a limited set of functions. For these reasons it was decided to develop a comprehensive, modifiable, geodatabase that will function in a modelling environment which will allow users to save their data in a centralised database. Additionally the functionality provided by other data models and modelling frameworks may be linked and used in the new modelling environment. A methodology that has been followed was to first establish the objectives of the research project, gather the necessary data, investigate various data models and hydrological modelling frameworks, determine the requirements for the modelling environment, design and create the modelling environment, design and create the geodatabase, and finally selecting the study area which will provide the research project with the necessary data. The following findings were made concerning the research project: firstly, that ArcHydro will be used as example data model to assist in designing the geodatabase. Secondly, that UML will be used as a development tool to assist with the development of the geodatabase. Thirdly, that the geodatabase will be generated from the XML schema and be made available to ArcCatalog. Fourthly, that data from different users/providers (Hydstra, Stats SA, Weather Bureau, Department of Water Affairs and Forestry, etc.) be inserted into the geodatabase. Fifthly, that any other hydrological modelling framework may make use of the data stored in the geodatabase. Finally, ArcGIS was selected as GIS application and Microsoft Access as a storage area.

It is common knowledge that water is one of the basic needs for human beings. However, the consumption of contaminated water can lead to waterborne diseases and fatalities. It is, therefore imperative to constantly monitor the quality of potable water. There are numerous technologies used for water quality monitoring. These technologies are relatively effective however these tests are expensive and complex to use, which then require experienced technicians to operate them. Other tests are not rapid, making consumers of water susceptible to waterborne diseases. In this study, dye-doped, surface functionalized silica nanoparticles (SiNPs) and surface-functionalized magnetic nanocomposites (MNCs) were proposed as materials that can be applied in order to reduce the time taken to get results as well as to make the processes less complex and portable. The aim of this study was to synthesize and characterize surface functionalized dye-doped SiNPs and surface functionalized MNCs for detection and preconcentration of in water. Additionally, proof of concept had to be shown using the synthesized materials. SiNPs were the materials of choice due to their easily functionalized surfaces and their strong optical properties. SiNPs are photostable and they do not leach in solution due to the inert nature of the silica matrix in aqueous media. MNCs were chosen as materials of choice for preconcentration of E. coli in water because they are easy to synthesize and they can be applied in various biological applications due to their functional groups. SiNPs were synthesized using the water-in-oil microemulsion. The SiNPs were further functionalized with amine and carboxyl groups and avidin. Thereafter, they were bioconjugated with biotinylated anti-E. coli antibodies. The pure and surface functionalized SiNPs were characterized using ATR-FTIR spectroscopy, FE-SEM, HR-TEM, Zeta Sizer, UV-vis spectroscopy and spectrofluorometry. The application of the dye—doped surface functionalized SiNPs in E. coli detection was characterized using the fluorescence plate reader. The SiNPs were spherical and uniform in size. They increased in size as they were being functionalized, ranging from 21.20 nm to 75.06 nm. The SiNPs were successfully functionalized with amine and carboxyl groups as well as with avidin and antibodies. Two methods were investigated for carboxyl group attachment (direct and indirect attachment) and the direct attachment method yielded the best results with a surface charge of -31.9 mV compared to -23.3 mV of the indirect method. The dye loading was found to be 1% after particle synthesis. The optical properties of the Ru(Bpy) dye were enhanced 3 fold when they were encapsulated in the Si matrix. The SiNPs were binding to the E. coli cells and enabled detection. MNCs were synthesized through in-situ polymerization. The MNCs were characterized using ATR-FTIR spectroscopy, SEM, TEM and XRD. The MNCs were successfully functionalized with carboxyl groups. The increase in size of the nanocomposites as seen in SEM images proved that the Fe3O4 was successfully encapsulated in the polymer matrix. The MNCs were proven to be magnetic by a simple magnetism test whereby they were separated in an aqueous solution using an external magnetic field. The antibody-labelled MNCs were binding to the E. coli cells as shown in TEM images. E. coli cells were removed from water at varying concentrations of 1x106 CFU/mL to 1x109 CFU/mL at 10 mL volumes. This study has demonstrated that dye-doped SiNPs amplify the signal of E. coli cells using fluorescence. The study has also demonstrated that the MNCs can be applied in sample preconcentration and enrichment for E. coli detection. However, further studies should investigate and optimize the combination of the two techniques in a point of use device for water quality testing of 100 mL-samples as per the requirement of the SANS 241 standard. / Civil and Chemical Engineering / M. Tech. (Chemical Engineering)

When designed, installed, and maintained properly, septic systems provide a cost-effective and environmentally-sound method to treat domestic wastewater. However, poor installation, unsuitable site conditions, and infrequent maintenance can lead to system failure and the discharge of partially-treated effluent to local waterways. As many as 1%, or 4,000 systems, fail each year in the Atlanta area. Therefore, the purpose of this paper is to evaluate what social and physical factors are significant to the location of on-site sewage management system failures in Cherokee County, Georgia. A regression analysis of the septic system failure rate, which was estimated with repair permit records from the local Board of Health, with Census demographics, soil, and septic system information found that the percent of soils in the “A” hydrologic group, unemployment rate, percent African-American population, population density, household size, percent of homes built between 1980 and 1989, percent built between 1970 and 1979, percent built between 1940 and 1949, and the average lot size of the parcels issued a repair permit were statistically-significant (p < 0.05) indicators of the failure rate at the Census block group level. The inclusion of socioeconomic, environmental, and physical characteristics suggests that the most effective response to reduce failures will incorporate actions to address these significant elements collectively. Despite restrictions on the ability of the Georgia Department of Public Health to regulate maintenance, many policy options are available to proactively identify areas with the greatest likelihood of failure and reduce the incidence of failure in those areas. Greater collaboration between stakeholders, including the county Board of Health and utility providers, improved record-keeping, and education and incentive programs provide the best opportunities to improve the management of septic systems in local jurisdictions.

This critical overview document (COD) presents, discusses and brings together the selected portfolio of publications that the author believes make a significant contribution to the field of wastewater treatment, focusing on the removal of endocrine disrupting chemicals (EDCs) in wastewater treatment applications. The aim of the research within this COD was to investigate the fate, mechanisms and optimisation of EDCs removal in wastewater treatment applications. The key objectives were to: 1. Investigate and understand the mechanisms of removal of EDCs in wastewater and sludge treatment processes. 2. Evaluate novel methods for the removal of EDCs in water and wastewater treatment applications. 3. Establish the kinetic and thermodynamic properties of the removal processes to inform process modelling of full scale design of treatment processes.

Integrated Coastal Zone Management (ICZM) is a dynamic process in which a coordinated strategy is developed and implemented for the allocation of environmental, socio-cultural, and institutional resources to achieve the conservation and sustainable multiple use of the coastal zone. The present study titled “Coastal Zone Management in Dubai with reference to ecological characterization” is an effort to consider critical water quality and ecological issues in the current and future coastal zone of Dubai Creek. The work included water quality, ecology and numerical modeling for predicting future conditions. This study is utmost significant due to management of critical coastal environmental issues (fish mortality, bad odour, unaesthetic view, algal bloom etc.) in Dubai Creek besides protection of internationally recognized bird sanctuary (Ras Al Khor Wildlife Sanctuary) and sustainable multibillion dollar of property developments as an extension of Dubai Creek. Comprehensive attempt made to collect primary data on water quality and ecology during 2005 and 2006 from specific monitoring stations spreading along Dubai Creek. The pragmatic results in Dubai Creek are alarming; the upper region is susceptible to high organic pollution which exhibits 3-122 folds high nutrients levels while biodiversity in the same region at the seabed is almost died and non-existing. The current assessment suggests a policy for the ICZM and an “Immediate Action Plan” for the beneficial and sustainable development of Dubai Creek. The study recommends the following mitigation as a tool for the management strategies of Dubai Creek lagoon: Dredging in the lagoon of Dubai Creek. -- Tertiary treatment of wastewater from Awir STP prior to discharge into the Creek or divert the discharge from the lagoon of Dubai Creek. -- A new Government Decree for the water quality thresholds in Dubai Creek.

published_or_final_version / Ecology and Biodiversity / Doctoral / Doctor of Philosophy

published_or_final_version / Environmental Management / Master / Master of Science in Environmental Management

published_or_final_version / Environmental Management / Master / Master of Science in Environmental Management