Abstract not available. / Thesis (M.T.R.P.)-University of Natal, 1997.

An important task of research on trace metals in soils is to evaluate how much metals are potentially bioavailable and may cause toxic effects. In this thesis, the chemical speciation and complexation of cadmium (Cd), copper (Cu), mercury (Hg) and lead (Pb) were examined in eastern Canadian soils collected from different locations around smelters. Our goal is to be able to predict metal binding in the soil solution and on the solid phase under a wide range of field conditions. / In Chapter 2, speciation of Cd, Cu and Pb in the lysimeter soil solutions was determined using an ion exchange technique (IET) involving a resin column. The IET-speciation data were used to estimate the metal-dissolved organic carbon (DOC) binding constants using the non-ideal competitive adsorption (MICA)-Donnan model, which assumed a continuous distribution of binding affinities on the DOC molecule. The published Cd and Pb speciation data in a variety of soils (Chapter 3) were also used to test the effectiveness of two speciation models, the MICA-Donnan model and WinHumicV. Both models satisfactorily predicted the concentrations of Cd2+ and Pb2+. The two chapters of metal speciation demonstrated that the NICA-Donnan model could estimate the binding strength of organic matter in soil solutions. / Proton and metal complexation to the surface of soil particles (Chapters 4 and 5) was investigated using back-titration and batch adsorption procedures. It was shown that the surface binding of H+, Cd2+, Hg2+ and Pb2+ was significantly related to soil organic matter (SOM). Though the soil particle surface was covered by a mixture of organic and mineral components, a two-site distribution could be identified from the titration curves. With the parameters derived from the back-titration and adsorption data, the MICA-Donnan model reasonably predicted the surface complexation of proton and metals. Furthermore, the statistically significant relationships between the model parameters and soil organic matter supported the assumptions in this thesis: (1) Organic matter was the most important sorbent on the particle surface; (2) The MICA-Donnan model may be used to interpret the surface binding data in these soils.

Stormwater runoff from log yards in different BC regions can affect aquatic habitats to varying degrees given differences in weather, water quality and tree species. The objective of this thesis was to compare runoff quality and total runoff loadings from a coastal and interior log yard. Chemical analyses, toxicity tests and treatments were conducted. Data were compared to criteria, statistically compared between sites and assessed for seasonal trends. Export coefficients (ECs) were compared between sites. Relationships between toxicological and chemical variables were explored statistically. Runoff toxicity was similar between sites and fairly low. LC50s for 48-hour Ceriodaphnia dubia tests ranged from 32.95 to > 100 and 58.70 to > 100 for coastal and interior runoff, respectively. Microtox ®.5 minute EC50s ranged from 27.12 to > 100 for coastal runoff and 22.22 to > 100 for interior runoff. Several metals and dehydroabietic acid (DHA) exceeded criteria in runoff from both sites. Biochemical oxygen demand, alkalinity, pH and metals were significantly higher (p < 0.05) at the interior site. Sodium and conductivity were higher at the coastal site. No seasonal differences in runoff quality were observed. Therefore, acute effects would occur during periods of high runoff, during autumn at the coastal site and late winter at the interior site. The unpaved interior site generated less runoff per square meter due to ground infiltration. ECs were comparable to the paved coastal site. Exceptions to this include tannins and lignin (11 fold higher at the coastal site) and DHA (9 fold higher at the interior site). C. dubia toxicity was partially associated with TSS for both sites. Tannins and lignins were correlated (r² =0.91) with C. dubia toxicity for coastal runoff. Tannin and lignin concentrations ranged from 45 to 263 mg/L and 43 to 75 mg/L in coastal and interior samples, respectively. Since results suggest that TSS is partially responsible for toxicity, and since contaminants are often bound to TSS, source control and treatment options for TSS should be implemented.

I write this thesis based on the premise that many environmental problems are the result of conventional community design. I argue that conventional community designs are "anti-ecological" because they consume too much energy, produce an extraordinary amount of waste, are car-oriented, ignore any relationship with the natural environment, and reflect the irresponsible attitude of man conquering nature. However, I suggest that ecologically responsible community design alternatives do exist. I refer to these alternatives as "ecological communities". These communities attempt to function as ecosystems that conserve natural resources, are self-regulating, and produce little waste. / I present the central principles of ecological communities, and then explore the validity of these assertions. Using five ecological communities from Northern Europe, I examine the following principles: (1) alternative energy systems at the community-scale, (2) wastewater treatment and water reclamation, (3) waste management in the community, (4) ecologically sustainable landscapes, and (5) environmentally responsible housing. / Finally, I present my observations and conclusions. The observations are intended to help community designers to understand the characteristics of ecological communities, and perhaps some of the conditions necessary for these communities to exist. The hope is that these observations may assist community designers avoid common mistakes on similar projects. The observations may shorten the time designers require to transfer their ideas from theory into practice. I conclude that when compared with conventional communities--not with perfection or the utopian dream--ecological communities and what they represent can provide designers with viable development alternatives.

Elevated toxaphene levels have been reported in the biota of the Arctic. The purpose of this study is to measure total toxaphene levels in food samples commonly consumed by the Canadian Inuit and study the relationship between concentrations of total toxaphene and individual congeners. A total of 127 Inuit food samples were collected for toxaphene analysis. Total toxaphene and the specific toxaphene congeners including Parlar #26, #40/41, #42, #44, #50 and #62 were detected in the food samples. Total toxaphene concentrations ranged from 13 to 2800 ng/g and various congener concentrations ranged from 0 to 610 ng/g. Concentrations of total toxaphene were strongly correlated with congener concentration in marine mammals and weaker in fish. The sum of congeners Parlar #26, #50 and #62 accounted for 0--15% of total toxaphene in fish and 0--66% in marine mammals. Regression models were used to estimate total toxaphene based on individual or combinations of congener concentrations. Dietary intake was estimated to be 1.07 and 0.78 mug/kg body weight per day in Chesterfield Inlet and Igloolik. Our results show that there is no general conversion factor that can be used to estimate total toxaphene concentrations based on congener measurements.

In Canada, regulations against the use of lead (Pb) shot for waterfowl hunting were first established in the early 1990s with the creation of a few non-toxic shot zones, and culminated with a national ban in 1997. Prior to establishment of the first non-toxic shot zones in Canada, a nation-wide survey of Pb accumulation in wing bones of young-of-the-year (YY) dabbling and diving ducks determined the incidence of elevated Pb exposure in different parts of the country (Scheuhammer & Dickson, 1996). The objective of the present study was to determine the incidence of elevated Pb accumulation in the same species several years after the national ban on Pb shot; to survey waterfowl hunters to determine approximate levels of compliance with the Pb shot ban; and to use stable Pb isotope analysis to help determine the relative importance of different sources of Pb exposure. / Wing bones from 721 YY black, mallard, and ring necked ducks, and 579 YY woodcock from selected zones in Ontario, Quebec, BC, and the Maritimes, Canada were analyzed for Pb using flame atomic absorption spectrometry. (Abstract shortened by UMI.)

Many low molecular weight chlorinated organic compounds produced by the pulp and paper industry during kraft bleaching of the wood pulp are toxic. Mass balance studies suggest that mineralization of chlorinated organics is occurring in pulp and paper mill wastewater treatment systems. To understand the nature of dechlorination activity, molecular tools such as oligonucleotide primers and corresponding DNA probes were developed to monitor the presence of microorganisms possessing key genes (dehalogenases) responsible for the degradation of chloroaliphatic organics in kraft pulp mill effluent treatment systems. Oligonucleotide primers designed from the coding sequence of known dehalogenases and a methane monooxygenase gene, which is known to catalyze dehalogenation reactions, were used for polymerase chain reaction (PCR) analysis, using genomic DNA extracted from dehalogenating bacterial isolates and total community DNA extracted from water and sediments of lagoon treatment systems. PCR amplification with dhlB oligonucleotide primers, designed from the haloacid dehalogenase of Xanthobacter autotrophicus, revealed the presence of dehalogenase genes in both aerated lagoons and stabilization basins. Similar results were obtained with mmoX primers designed from the methane monooxygenase gene of Methylococcus capsulatus. DNA sequence analysis of several PCR fragments showed significant similarity to known dehalogenase genes. The molecular tools developed in this study revealed the presence of different types of microorganisms with dechlorination potential in the microbial community of pulp mill effluents.

The objective was to analyze the effects of logging and prescribed burning on carabid beetles (Coleoptera: Carabidae) at a jack pine stand and white spruce plantations in order to assess short-term impacts of these forestry practices on the diversity of this beetle group. In addition, soil scarification was also included at the jack pine stand. Based on previous reports on forest disturbance influences on carabids, it is hypothesized that short-term effects of studied forestry practices do not reduce carabids' diversity. Four carabid assemblage characteristics were compared: (a) number of catches; (b) dry mass; (c) species richness; and, (d) diversity index. Species responses and dry mass distributions were also investigated. Treatments either increased or maintained studied variables compared with control sites. Diversity indices were highest in burnt-over areas. Similar response patterns of species or groups of species were observed in both forest types. The presence of regenerating sites among the natural landscape increased carabid diversity.

Estuaries, the interface of interaction of fluvial discharge and marine action serve as temporary repositories of materials (solid and dissolved) before finally exporting them to sea. This interchange of material is dependent on a range of factors such as tidal range, prism, and symmetry; fluvial flows and estuarine morphodynamics. The efficacy of transfer of materials to the marine environment is important for estuarine health particularly in estuaries located in highly developed areas such as the major coastal metropolitan areas of many countries. This study assesses the efficacy of the export of nitrates from three estuaries of the eThekwini Municipality of the city of Durban, South Africa which maintain an open mouth status, ensuring tidal exchange throughout the year. The focus of this study was to determine and analyze the net flux of nitrates between the Isipingo, Mgeni, and Tongati estuaries of the eThekwini Municipality, and their adjacent nearshore environments. It questioned whether the Isipingo, Mgeni, and Tongati estuaries were efficient at exporting nitrates to their adjacent marine environments. The abovementioned estuaries are classified as temporarily open/closed estuaries, and were chosen for this study, as they maintain an open mouth status for most of the year. An open mouth condition was critical in order to conduct this study, as tidal exchange, and the resulting nitrate fluxes, could occur. The net flux of nitrates was measured for these estuaries on a seasonal basis for both spring and neap tides. Measurements were taken over the tidal cycle, ensuring that the peak high and low tides were sampled. To determine the values of net flux, the cross-sectional area of the estuary mouths were measured; average flow velocities of water were measured; and average concentrations of nitrates were obtained. Results indicate that although there is a net export of nitrates to the nearshore environment, there were instances, particularly on the spring tide, when a net import of nitrates into the estuary occurred. The origin of the latter is likely derived from nearshore upwelling; unusually high biotic decomposition at sea and/or the longshore drift transport of decomposing sewage outfall. This creates an added dimension for consideration in estuarine management plans. Taking all three estuaries studied into consideration, a net export of nitrates for all seasons for the eThekwini Municipality was measured with a clear seasonal influence detected where high rainfall seasons led to greater export as a consequence of greater fluvial flows, erosion and leaching of agricultural lands and longer ebb duration. / Thesis (M.Sc.)-University of KwaZulu-Natal, Westville, 2011.

Sustainable development is often described in three dimensions, namely social, environmental and economic. Environmental Management Accounting (EMA) is a management accounting approach which brings the environmental impact of the process to the attention of the stakeholders whilst also looking at the economic aspect so as to control costs. While EMA’s application has been adopted widely in developed countries, does the same apply in South Africa? Seeking to understand the level of current EMA being conducted at the corporate level will assist government and corporations in South Africa to understand the factors encouraging better accounting sustainability. The focus of this study was confined to leaders of organisations operating in the KwaZulu-Natal (KZN) province of South Africa. Quantitative research was conducted on 40 organisations that operated in KZN. The organisations sampled ranged from small to large enterprises, and operated in a number of different industries. The study centred on analysing the organisation’s attitude towards environmental sustainability, the types of EMA reports generated and reasons for or against using EMA. The research revealed that the attitude by each organisation towards environmental sustainability was vital in encouraging organisations to implement EMA as a method of controlling pollution. The majority of organisations had applied some form of EMA in their KZN organisation. A major finding was that for those who chose to apply EMA, their most important reason was to control costs better. The second reason for applying EMA was legislation. Planned implementation of EMA was analysed and a number of specific industries and sizes of industries were highlighted for their implementation of EMA or lack thereof. This research is useful to the reader as it has analysed the current application of EMA to encourage sustainable development, identify the general obstacles encountered to application of EMA and recommend strategies that can be employed to overcome them. These recommendations include government involvement through education programmes to improve the understanding and attitude towards EMA. Secondly, government should pass legislation making environmental reporting a compulsory disclosure for all organisations. Organisations themselves should use advanced computerised recording systems to develop their application of EMA. Larger businesses should encourage and assist smaller organisations in their supply chains to become more active in their own environmental protection. / Thesis (MBA)-University of KwaZulu-Natal, Westville, 2011.