The Atherton Tablelands basalt aquifer is a major source of groundwater supply for irrigation and other agricultural use. The Tertiary to Quaternary age basaltic aquifer can be regarded as a generally unconfined, layered system, comprising numerous basalt flows separated by palaeo-weathering surfaces and minor alluvial gravels of palaeo-drainage channels. Layers of massive basalt and clay-rich weathered zones act as local aquitards, with some local perched aquifers also present. The aquifer is regarded as a system in which several factors interact to produce the overall characteristics of the hydrogeochemistry of the groundwaters. They include the mineralogical composition of both the basalt aquifer and the thick overlying weathered zone, the porosity and permeability of the basalt aquifer, its thickness, bedrock composition, and climate and topography. The hydrogeochemical processes operating in this aquifer system have been investigated though the analysis of 90 groundwater samples collected from October 1998 to October 1999, groundwater chemistry data provided by the Queensland Department of Natural Resources & Mines for more than 800 groundwater samples, rain water samples collected during 1999 by CSIRO, stream chemistry data provided by CSIRO and James Cook University, and mineralogical and whole rock geochemistry data of drill chip samples. The methods used in this research study include the assessment of groundwater major ion chemistry data and field physico-chemical parameters using hydrochemical facies and statistical approaches, investigation of the mineralogical composition of the aquifer, assessment of concentrations and activities of the ions in solution, the degree of saturation with respect to both primary and secondary minerals, and hydrogeochemical modelling to determine the likely controls on the chemical evolution of these groundwaters. The basaltic groundwaters are mostly Mg-Ca-Na, HCO3 type waters, with electrical conductivities generally less than 250 μS/cm and pH values from 6.5 to 8.5. Dissolved silica (H4SiO4) comprises a large proportion of the total dissolved load, with average concentrations of around 140 mg/L. Concentrations of potassium, chloride and sulphate are low, that is, generally less than 3 mg/L, 15 mg/L and 10 mg/L, respectively. Despite the very low salinity of the Atherton Tablelands basalt groundwaters, the relative concentrations of the major ions are comparable to groundwaters from other basaltic regions, and are consistent with expected waterrock interactions. A variety of multivariate statistical techniques may be used to aid in the analysis of hydrochemical data, including for example, principal component analysis, factor analysis and cluster analysis. Principal component factor analyses undertaken using the hydrochemical data for the Atherton groundwaters has enabled the differentiation of groundwaters from various lithological formations, the underlying geochemical processes controlling groundwater composition in the basalt aquifer to be inferred, relative groundwater residence and flow directions to be inferred and mapping of the estimated thickness of the basalt aquifer. The limitations of multivariate statistical methods have been examined, with emphasis on the issues pertinent to hydrochemical data, that is, data that are compositional and typically, non-normally distributed. The need to validate, normalize and standardize hydrochemical data prior to the application of multivariate statistical methods is demonstrated. Assessment of the saturation states of the Atherton basalt groundwaters with respect to some of the primary minerals present indicate that the groundwaters are mostly at equilibrium or saturated with respect to K-feldspar, and approach equilibrium with respect to the plagioclase feldspars (albite and anorthite) with increasing pH. These groundwaters are at equilibrium or saturated with respect to the major secondary minerals, kaolinite, smectite (Ca-montmorillonite) and gibbsite. They also tend to be saturated with respect to the oxidation products, goethite and hematite, common accessory minerals in the Atherton Tablelands basalt sequence. Silicate mineral weathering processes are the predominant influence on the composition of these basalt groundwaters. These weathering processes include the weathering of pyroxenes, feldspars and other primary minerals to clays, aluminium and iron oxides, amorphous or crystalline silica, carbonates and zeolites, releasing ions to solution. The contribution of substantial organic carbon dioxide to the groundwater is an important factor in the extent to which silicate mineral weathering occurs in this aquifer system. Evaporative enrichment of recharging waters, oxidation and ion-exchange reactions and the uptake of ions from, and decomposition of, organic matter, are processes that have a minor influence on the composition of the basalt groundwaters. The relationships observed between mineralogical compositions, basalt character and groundwater occurrence in the Atherton Tablelands region improved the understanding how groundwater is stored and transmitted in this basalt aquifer system. Groundwater is mostly stored in vesicular basalt that may be fresh to highly weathered, and movement of this water is facilitated by pathways through both vesicular and fractured basalt. Related work undertaken as part of this research project showed that the groundwater flow patterns defined by the hydrogeochemical interpretations correspond well with the spatial trends in water level fluctuations, and response to recharge events in particular. Groundwater baseflow to streams and discharge to topographic lows in the Atherton Tablelands region is indicated by the relationships between the major cations and anions in the stream waters. Fracture zones are likely to be preferred pathways of groundwater movement. Recharge estimates, based on a chloride mass balance, range from 310 mm/yr in the north-western part of the study area (north of Atherton) to 600 mm/yr in the wetter southern and eastern parts of the study area. These recharge estimates should be treated with caution however, due to the low groundwater chloride concentrations and the high variability in rainfall chloride concentrations. The findings of this research project have improved the understanding of the hydrogeochemical processes controlling the composition of the low salinity basalt groundwaters in the Atherton Tablelands region, and are applicable to other basalt groundwater systems, particularly those in high rainfall environments.

In Taiwan, more than 20% of the major rivers are mildly to heavily pollute by domestic, industrial, and agricultural wastewaters due to the low hook-up rate of public underground sewerage systems in rural areas. Thus, constructed or engineered wetlands have been adopted as the major alternatives to cleanup polluted rivers. Constructed wetlands are also applied as the tertiary wastewater treatment systems to polish the secondary wastewater effluents to meet water reuse standards with lower operational costs. The studied Kaoping River Rail Bridge Constructed Wetland (KRRBCW) is the largest constructed wetland in Taiwan. It is a multi-function wetland and is used for polluted creek water purification and secondary wastewater polishment before they discharge into the Kaoping River. Although constructed wetlands are feasible for contaminated water treatment, wetland sediments are usually the sinks of organics and metals. In this study, water, sediment and macrophytes samples were collected from the major wetland basins in KRRBCW. The quarterly investigation (from 2007 to 2009) results show that more than 97% of total coliforms (TC), 55% of biochemical oxygen demand (BOD), and 30% of nutrients [e.g., total nitrogen (TN), total phosphorus (TP)] were removed via the constructed wetland system. However, results from the sediment analyses show that wetland sediments contained high concentrations of metals (e.g., Cu, Fe, Zn, Cr, and Mn), organic contents (sediment oxygen demand = 1.7 to 7.6 g O2/m2-d), and nutrients (up to 18.7 g/kg of TN and 1.22 g/kg of TP). Thus, sediments should be excavated periodically to prevent the release the pollutants into the wetland system and causing the deterioration of wetland water quality. Results of polymerase chain reaction (PCR), denaturing gradient gel electrophoresis (DGGE), and nucleotide sequence analysis reveal that an increase in microbial diversities in the wetland systems was observed. Results from the DGGE analysis indicate that all sediment samples contained significant amounts of microbial ribospecies, which might contribute to the carbon degradation and nitrogen removal. Gradually disappearing of E. coli was also observed along the flow courses through the natural attenuation mechanisms. The factor analysis of SPSS 12.0 shows that 17 water-quality items of the study site could obtain four to six principal components, including nitrate factor, phosphorus factor, eutrophication factor, organic factor, and environmental background factor, the major influencing components are nutrition factor and eutrophication factor. The ponds of the study site were classified into two or three clusters depend on in-and-out flow location. This study attempted to establish a forecasting model of wetland pollutants concentration through the time series (ARIMA), results show that the outcome of the B7 pond was better than others. Results indicate that the ARIMA model can be used to simulate the trend of treatment efficiency using the wetland system. Experience and results obtained from this study would provide solutions for water quality control. Thus, the wetland system has a significant effect on water quality improvement and is capable of removing most of the pollutants from the local drainage system before they are discharged into the downgradient water body. Other accomplishments of this constructed wetland system include the following: providing more green areas along the riversides, offering more water assessable eco-ponds and eco-gardens for public, and rORPabilitating the natural ecosystem. The Kaoping River Rail Bridge Constructed Wetland has become one of the most successful multi-function constructed wetlands in Taiwan. The experience obtained from this study will be helpful in designing similar natural treatment systems for river water quality improvement and wastewater treatment.

To determine the relationship between vegetation and environmental parameters in the middle and upper watershed of Nan-Tze-Shian stream, the first comprehensive multivariate statistical analysis of the woody vegetation data obtained from field survey, is presented. According to physiognomy and plant composition, 70 homogenous stands were sampled in the area. Each plot is composed of twenty 5 ¡Ñ 5 m2 quadrates. Five environmental factors including plot location, altitude, slope, aspect and microtopography were recorded. All woody plants in each plot species with dbh ≥ 1cm present in the quadrates were identified, and their dbh were measured. In addition, ground layer species were identified and evaluated by their coverage. The vascular plants inventory recorded a total of 118 families, 321 genera and 563 species. Among the 203 woody plants, the families are rich in species including Lauraceae, Fagaceae, Theaceae, Symploaceae and Moraceae. Detrended correspondence analysis (DCA) was applied to the ordination analysis, to clarify the spatial variation of the 70 plots and search for relationship of the variation with 5 environmental variables. Classification of the vegetation types was conducted by the cluster analysis (CA), two-way indicator species analysis (TWINSPAN) and tabular comparison method. The results obtained from the analysis are that the distribution of vegetation types and flora are obvious and sensitive to the elevation and whole light sky space (WLS) and the floristic classification distinguished 9 forest types: Neolitsea acuminatissima - Cyclobalanopsis morii, Vaccinium randaiense - Castanopsis cuspidata, Pasania kawakamii - Cyclobalanopsis stenophylloides, Beilschmiedia erythrophloia, Engelhardtia roxburghiana - Cyclobalanopsis longinux, Helicia formosana - Machilus konishii kusanoi, Castanopsis formosana, Machilus zuihoensis - Schefflera octophylla and Ficus irisana - Machilus kusanoi associations. The associations were re-arranged by tabular comparison method for developing a hierachy of forest vegetation system. This hierachical system consists of Three alliances, characterized by Cyclobalanopsis stenophylloides, Beilschmiedia erythrophloia and Machilus kusanoi, respectively. Finally, I ascribed the vertical vegetation spectrum along with altitude gradient. The altitudinal boundaries between upper Quercus, lower Quercus and Machilus-Castanopsis zones are ca. 1800 m and 1200 m, respectively. The results might help us to understand the habitat diversity and plant diversity in the area, and those are expected to apply to vegetation mapping and environment monitoring.

No description available.

Orientador: Paulina Setti Riedel / Banca: Paulo Milton Barbosa Landim / Banca: Diana Sarita Hamburger / Resumo: As imagens de satélite, por serem um registro de alvos com diferentes comportamentos espectrais e diferentes arranjos espaciais, respondem com variações tonais de cinza e variações texturais. Esta variação textural é analisada normalmente através de interpretação visual, que é uma sistematização de várias técnicas, as quais convergem para um único objetivo, a compartimentação da imagem. Em geral, a textura apresenta-se como sendo uma arma valiosa na interpretação de formas de relevo, drenagem e de padrões da cobertura vegetal e de uso da terra. Acredita-se que, a partir da utilização das técnicas de processamento digital de imagens e técnicas estatísticas multivariadas, como subsidiária na redução do caráter subjetivo da análise textural e da correspondência entre zonas homólogas, será possível favorecer a discriminação de elementos imageados, e encontrar um modelo que possibilite explicar mais satisfatoriamente a compartimentação e a relação de equivalência entre zonas que constituem texturas semelhantes. Desta forma, o objetivo geral do trabalho, é avaliar diversas metodologias, com intuito de realizar uma compartimentação fisiográfica, explorando o aspecto textural da imagem além da similaridade existentes entre as áreas após compartimentada. A área de estudo abrange os municípios de Itanhaém e Peruíbe localizados no litoral sul do Estado de São Paulo. A partir dos resultados obtidos, verificou-se que o método convencional de fotointerpretação juntamente com a aplicação da análise estatística multivariada, mostrou-se viável de ser aplicado apresentando resultados satisfatórios e inovadores. Já no processamento de alguns algoritmos de textura a redução de informações foi bastante grande, devido à redução dos valores de níveis de cinza e à homogeneização dos alvos; mostrando que o resultados não foram positivos...(Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Satellite images record surface features based on their different spectral behaviors and spatial arrangements. As such, these features are discernable from different shades of gray and textural variations seen in the images. These textural variations represent a systematic utilization of various techniques, which converge for a single objective: compartmentalization of the image. In general, texture is used as an important tool in the interpretation of relief forms, drainage patterns and vegetative cover and land-use patterns. Through the application of digital processing techniques and multivariable statistical analyses, it is possible to reduce the subjective character of textural analysis and correspondence between homologous zones, hence enhance the discrimination of different elements in an image. These methods can help find a model that allows for a better explanation of the compartmentalization and equivalence between zones that consist of similar textures. In this form, the general objective of the study is to evaluate diverse methodologies with the objective of determining the physiographic compartmentalization, exploiting the textural aspect of the image in addition to the existing similarities between areas following compartmentalization. The study area is within the municipalities of Itanhaém e Peruíbe, located along the south coastal region of São Paulo State. Based on the results obtained, it is confirmed that the conventional method of photo-interpretation, together with the application of multivariate statistical analysis, shows that it is a viable combination, yielding both satisfactory and innovative results. Already, in the processing of some textural algorithms, the reduction of information was significant, owing to the reduction of the values in the shades of gray and to the homogenization of targets, showing that the results were not positive...(Complete abstract click electronic access below) / Mestre

As dificuldades de aprendizagem sobre estatística e suas aplicações simplesmente em razão da matemática envolvida, principalmente, pelos alunos dos cursos de humanas, fazem dela um desafio para o professor que a ministra e também para o aluno que aprende. Assim, esta tese busca mostrar o quanto à elaboração e o desenvolvimento de uma ferramenta de avaliação tipo teste em um ambiente virtual pode contribuir como apoio ao ensino presencial do estudo de ferramentas estatísticas multivariadas para os alunos de graduação em Administração da FEARP/USP, matriculados na disciplina Estatística Aplicada à Administração II. Este trabalho faz parte do projeto virtual denominado LaViE, que é um ambiente virtual de ensino-aprendizagem de estatística, e que está fundamentado em três dimensões: Pedagogia Virtual, Tecnologia da Comunicação e Processo de Validação. Para a criação dessa ferramenta de avaliação tipo teste online foi necessário, primeiramente, a elaboração de um protocolo para desenvolvimento e implementação desse sistema no LaViE. A metodologia, então, foi baseada em três etapas: 1) elaboração do protocolo fundamentado na pesquisa exploratória de pedagogia virtual com base na teoria sobre processo de ensino-aprendizagem para o desenvolvimento de um conjunto de regras e passos que balizasse a criação de questões testes on-line com níveis diferentes de ?adaptação? pelo aluno para cada módulo apresentado na disciplina em questão. Neste caso, foram criados três níveis de adaptação: básico (I), intermediário (II) e avançado (III); 2) implementação dessa ferramenta de avaliação no LaViE (teste seu conhecimento), com o desenvolvimento das questões baseadas nos assuntos sobre análise estatística multivariada e; 3) avaliação quantitativa da opinião dos alunos (usuários) quanto à usabilidade do sistema ?teste seu conhecimento? desenvolvido. Esses dados foram coletados quando essa disciplina foi ministrada, porém em dois períodos diferentes; no segundo semestre de 2005 como projeto-piloto, e no segundo semestre de 2006. Dessa forma, pôde ser feita uma análise comparativa da opinião dos alunos sobre o sistema em dois momentos diferentes. Para esse levantamento foram utilizados dois questionários aplicados diretamente aos alunos em sala de aula momentos antes da avaliação presencial da disciplina e um outro logo após essa avaliação presencial. Essas três etapas finalizadas deram condição de existência de uma ferramenta que faz parte de uma das três dimensões citadas do LaViE ? Processo de Validação. / The mathematical knowledge involved in the process of learning statistics and its applications, brings about difficulties to the Humanities department students, thus making it a challenge not only to those who teach it but also to the ones who learn it. Therefore, this work aims at showing the contribution the elaboration and development of a tool such as an online evaluation test can give, as a support to the presencial teaching of the study of multivariate statistical resources, to the FEARP/USP Business Management undergraduate students, registered in Applied Statistics to Business Management II. This study is part of a virtual project named LaViE which is a virtual environment of teaching-learning of Statistics based on three dimensions: Virtual Pedagogy, Communication Technology and Validation Process. For the development and implementation of the online evaluation test in the LaViE project, a protocol was elaborated. The methodology involved is based on three phases: 1) protocol production built on the virtual pedagogy exploratory research founded on the theory concerning the teaching-learning process in order to develop a set of rules and measures which support the creation of online test problems presenting different levels of adaptation for each module of the mentioned discipline. Thus, three levels of adaptation were created: basic (I), intermediate (II), and advanced (III); 2) implementation of such evaluation tool in the LaViE project (test your knowledge) by developing questions based on topics about multivariate statistical analysis; 3) quantitative evaluation of the users? opinion as to the usability of the ?test your knowledge? system. Data were collected in two distinct occasions: second semester of 2005, as a pilot project, and second semester of 2006, what enabled a comparative analysis of the system by the users at two different moments. This survey was conducted by means of two questionnaires completed in class by the students, being the first before the presencial discipline evaluation, and the second immediately after it. At the completion of the three phases previously mentioned, the Validation Process was obtained.

Made available in DSpace on 2014-06-11T19:26:11Z (GMT). No. of bitstreams: 0 Previous issue date: 2003Bitstream added on 2014-06-13T18:54:15Z : No. of bitstreams: 1 moreira_mr_me_rcla.pdf: 4230931 bytes, checksum: d03e922a64150ccc7e14429414e1555c (MD5) / As imagens de satélite, por serem um registro de alvos com diferentes comportamentos espectrais e diferentes arranjos espaciais, respondem com variações tonais de cinza e variações texturais. Esta variação textural é analisada normalmente através de interpretação visual, que é uma sistematização de várias técnicas, as quais convergem para um único objetivo, a compartimentação da imagem. Em geral, a textura apresenta-se como sendo uma arma valiosa na interpretação de formas de relevo, drenagem e de padrões da cobertura vegetal e de uso da terra. Acredita-se que, a partir da utilização das técnicas de processamento digital de imagens e técnicas estatísticas multivariadas, como subsidiária na redução do caráter subjetivo da análise textural e da correspondência entre zonas homólogas, será possível favorecer a discriminação de elementos imageados, e encontrar um modelo que possibilite explicar mais satisfatoriamente a compartimentação e a relação de equivalência entre zonas que constituem texturas semelhantes. Desta forma, o objetivo geral do trabalho, é avaliar diversas metodologias, com intuito de realizar uma compartimentação fisiográfica, explorando o aspecto textural da imagem além da similaridade existentes entre as áreas após compartimentada. A área de estudo abrange os municípios de Itanhaém e Peruíbe localizados no litoral sul do Estado de São Paulo. A partir dos resultados obtidos, verificou-se que o método convencional de fotointerpretação juntamente com a aplicação da análise estatística multivariada, mostrou-se viável de ser aplicado apresentando resultados satisfatórios e inovadores. Já no processamento de alguns algoritmos de textura a redução de informações foi bastante grande, devido à redução dos valores de níveis de cinza e à homogeneização dos alvos; mostrando que o resultados não foram positivos... / Satellite images record surface features based on their different spectral behaviors and spatial arrangements. As such, these features are discernable from different shades of gray and textural variations seen in the images. These textural variations represent a systematic utilization of various techniques, which converge for a single objective: compartmentalization of the image. In general, texture is used as an important tool in the interpretation of relief forms, drainage patterns and vegetative cover and land-use patterns. Through the application of digital processing techniques and multivariable statistical analyses, it is possible to reduce the subjective character of textural analysis and correspondence between homologous zones, hence enhance the discrimination of different elements in an image. These methods can help find a model that allows for a better explanation of the compartmentalization and equivalence between zones that consist of similar textures. In this form, the general objective of the study is to evaluate diverse methodologies with the objective of determining the physiographic compartmentalization, exploiting the textural aspect of the image in addition to the existing similarities between areas following compartmentalization. The study area is within the municipalities of Itanhaém e Peruíbe, located along the south coastal region of São Paulo State. Based on the results obtained, it is confirmed that the conventional method of photo-interpretation, together with the application of multivariate statistical analysis, shows that it is a viable combination, yielding both satisfactory and innovative results. Already, in the processing of some textural algorithms, the reduction of information was significant, owing to the reduction of the values in the shades of gray and to the homogenization of targets, showing that the results were not positive...(Complete abstract click electronic access below)

As dificuldades de aprendizagem sobre estatística e suas aplicações simplesmente em razão da matemática envolvida, principalmente, pelos alunos dos cursos de humanas, fazem dela um desafio para o professor que a ministra e também para o aluno que aprende. Assim, esta tese busca mostrar o quanto à elaboração e o desenvolvimento de uma ferramenta de avaliação tipo teste em um ambiente virtual pode contribuir como apoio ao ensino presencial do estudo de ferramentas estatísticas multivariadas para os alunos de graduação em Administração da FEARP/USP, matriculados na disciplina Estatística Aplicada à Administração II. Este trabalho faz parte do projeto virtual denominado LaViE, que é um ambiente virtual de ensino-aprendizagem de estatística, e que está fundamentado em três dimensões: Pedagogia Virtual, Tecnologia da Comunicação e Processo de Validação. Para a criação dessa ferramenta de avaliação tipo teste online foi necessário, primeiramente, a elaboração de um protocolo para desenvolvimento e implementação desse sistema no LaViE. A metodologia, então, foi baseada em três etapas: 1) elaboração do protocolo fundamentado na pesquisa exploratória de pedagogia virtual com base na teoria sobre processo de ensino-aprendizagem para o desenvolvimento de um conjunto de regras e passos que balizasse a criação de questões testes on-line com níveis diferentes de ?adaptação? pelo aluno para cada módulo apresentado na disciplina em questão. Neste caso, foram criados três níveis de adaptação: básico (I), intermediário (II) e avançado (III); 2) implementação dessa ferramenta de avaliação no LaViE (teste seu conhecimento), com o desenvolvimento das questões baseadas nos assuntos sobre análise estatística multivariada e; 3) avaliação quantitativa da opinião dos alunos (usuários) quanto à usabilidade do sistema ?teste seu conhecimento? desenvolvido. Esses dados foram coletados quando essa disciplina foi ministrada, porém em dois períodos diferentes; no segundo semestre de 2005 como projeto-piloto, e no segundo semestre de 2006. Dessa forma, pôde ser feita uma análise comparativa da opinião dos alunos sobre o sistema em dois momentos diferentes. Para esse levantamento foram utilizados dois questionários aplicados diretamente aos alunos em sala de aula momentos antes da avaliação presencial da disciplina e um outro logo após essa avaliação presencial. Essas três etapas finalizadas deram condição de existência de uma ferramenta que faz parte de uma das três dimensões citadas do LaViE ? Processo de Validação. / The mathematical knowledge involved in the process of learning statistics and its applications, brings about difficulties to the Humanities department students, thus making it a challenge not only to those who teach it but also to the ones who learn it. Therefore, this work aims at showing the contribution the elaboration and development of a tool such as an online evaluation test can give, as a support to the presencial teaching of the study of multivariate statistical resources, to the FEARP/USP Business Management undergraduate students, registered in Applied Statistics to Business Management II. This study is part of a virtual project named LaViE which is a virtual environment of teaching-learning of Statistics based on three dimensions: Virtual Pedagogy, Communication Technology and Validation Process. For the development and implementation of the online evaluation test in the LaViE project, a protocol was elaborated. The methodology involved is based on three phases: 1) protocol production built on the virtual pedagogy exploratory research founded on the theory concerning the teaching-learning process in order to develop a set of rules and measures which support the creation of online test problems presenting different levels of adaptation for each module of the mentioned discipline. Thus, three levels of adaptation were created: basic (I), intermediate (II), and advanced (III); 2) implementation of such evaluation tool in the LaViE project (test your knowledge) by developing questions based on topics about multivariate statistical analysis; 3) quantitative evaluation of the users? opinion as to the usability of the ?test your knowledge? system. Data were collected in two distinct occasions: second semester of 2005, as a pilot project, and second semester of 2006, what enabled a comparative analysis of the system by the users at two different moments. This survey was conducted by means of two questionnaires completed in class by the students, being the first before the presencial discipline evaluation, and the second immediately after it. At the completion of the three phases previously mentioned, the Validation Process was obtained.

>Magister Scientiae - MSc / Groundwater is one of the most valuable natural resources on earth and it forms an important part of the total water resources of South Africa. For this reason, this resource should be monitored and controlled on a regular basis. The study was conducted in Newcastle, in the KwaZulu-Natal province of South Africa. The aim of this study was to assess groundwater quality geochemically and determine its suitability for domestic and irrigation purposes. For the purpose of this study 31 samples were collected from 31 boreholes in and around the town of Newcastle. The samples were analysed for Magnesium (Mg2+), Calcium (Ca2+), Sodium (Na+), Potassium (K+), Chloride (Cl-), Sulfate (SO42-), Bicarbonate (HCO3-), Nitrate (NO3-), Fluoride (F-) (pH, TDS and Ec. The SAQWG (DWAF, 1996) and the WHO (2011) water standards were used as the basis of evaluating the suitability of groundwater for drinking purposes. For irrigation, Electrical Conductivity (EC), Sodium Percent (Na %), Sodium Adsorption Ratio (SAR), Residual Sodium Carbonate (RSC), Kelly’s Ratio (KR), Magnesium Ratio (MR) and Permeability Index (PI) were used to evaluate suitability. Classical hydro-chemical methods together with multivariate statistical methods were used to further understand the composition controlling processes. Lastly, the spatial distribution of the results was presented using ArcGIS. The results showed that the groundwater is alkaline in nature and that most of the samples are within the permissible range of both SAWQG (DWAF, 1996) and WHO (2011). Few samples showed concentration of Na+, Cl-, SO42- , F- and TDS above the guideline value as per WHO (2011) standards. The order of abundance of major ions in the groundwater, based on their mean values is as follows: Na+>Ca2+>Mg2+>K+ and HCO3->SO42- >Cl->NO3-. Classical hydro-chemical methods revealed four hydro-chemical facies in the study area, which are Ca-Mg-HCO3, Na-HCO3, Ca-Na-SO4-HCO3 and Na-Cl. The major ion chemistry analysis revealed that the main composition controlling processes in the study area is rock-water interaction. It further revealed that the ionic concentration is due to silicate weathering, carbonate weathering, cation exchange, gypsum dissolution and halite dissolution. Factor analysis indicated three factors, which explained 79.71 % of the total variance in the water quality data. The first factor which accounted for the highest variance in the data was the Alkalinity factor, followed by the Hardness factor and the Anthropogenic factor which accounted for the least variance. The cluster analysis revealed five clusters and discriminant analysis showed that Na+, TH, HCO3- and SO42- discriminate these clusters by 96.8%. In conclusion, the study revealed that the groundwater in most of the boreholes in the study area is generally suitable for drinking and irrigation. This is with exception to boreholes 13 and 31 which showed concentrations higher than the permitted level by WHO (2011) standards of TDS, Na+, Cl-, SO42- and F-. Similarly, 45.16% the groundwater samples showed that the groundwater has high sodium hazard potential which makes water from these boreholes unsuitable for irrigation purposes without proper treatment. accounted for the least variance. The cluster analysis revealed five clusters and discriminant analysis showed that Na+, TH, HCO3- and SO42- discriminate these clusters by 96.8%. accounted for the least variance. The cluster analysis revealed five clusters and discriminant analysis showed that Na+, TH, HCO3- and SO42- discriminate these clusters by 96.8%.In conclusion, the study revealed that the groundwater in most of the boreholes in the study area is generally suitable for drinking and irrigation. This is with exception to boreholes 13 and 31 which showed concentrations higher than the permitted level by WHO (2011) standards of TDS, Na+, Cl-, SO42- and F-. Similarly, 45.16% the groundwater samples showed that the groundwater has high sodium hazard potential which makes water from these boreholes unsuitable for irrigation purposes without proper treatment.

No description available.