Hui Wing-chi. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2001. / Includes bibliographical references (leaves 127-141). / Abstracts in English and Chinese. / LIST OF TABLES --- p.xi / LIST OF FIGURES --- p.xiii / LIST OF ACRONYMS --- p.xvii / Chapter CHAPTER ONE- --- INTRODUCTION / Chapter 1.1 --- Background --- p.1 / Chapter 1.2 --- Conceptual Framework and Study Objectives --- p.7 / Chapter 1.3 --- Scope of the Research and Study Area --- p.10 / Chapter 1.3.1 --- Location and Climate --- p.10 / Chapter 1.3.2 --- Geology --- p.12 / Chapter 1.3.3 --- Landuse Characteristics and Status of Water Quality --- p.13 / Chapter 1.4 --- Significance of Study --- p.14 / Chapter 1.5 --- Organization of Thesis --- p.16 / Chapter CHAPTER TWO - --- LITERATURE REVIEW / Chapter 2.1 --- Landuse Alteration --- p.17 / Chapter 2.1.1 --- Urbanization and Landuse Changes --- p.17 / Chapter 2.1.2 --- Detecting Landuse Changes in Urbanizing Region --- p.19 / Chapter 2.2 --- Impact of Landuse Alteration on Water Quality --- p.21 / Chapter 2.2.1 --- Point and Nonpoint Sources of Water Pollution --- p.22 / Chapter 2.2.2 --- Nonpoint Source Pollution as a Worldwide Environmental Problem --- p.23 / Chapter 2.2.3 --- Methods of Assessing Nonpoint Source Pollution --- p.24 / Chapter 2.2.4 --- GIS-based Modeling of Nonpoint Source Pollution --- p.26 / Chapter 2.2.5 --- Application of Remote Sensing on Water Quality Study --- p.27 / Chapter 2.3 --- Landuse Changes and Their Water Quality Impacts in the Pearl River Delta --- p.28 / Chapter 2.3.1 --- Economic Reform and Urbanization --- p.29 / Chapter 2.3.2 --- Urban Redevelopment --- p.31 / Chapter 2.3.3 --- Rural Industrialization --- p.33 / Chapter 2.3.4 --- Water Pollution --- p.34 / Chapter CHAPTER THREE - --- METHODOLOGY / Chapter 3.1 --- Introduction --- p.36 / Chapter 3.2 --- Computation of Areal Nonpoint Source Pollution Loading --- p.38 / Chapter 3.2.1 --- Assumptions --- p.38 / Chapter 3.2.2 --- Soil Conservation Service (SCS) Curve Number Method --- p.39 / Chapter 3.2.3 --- Generation of Nonpoint Source Pollutants --- p.42 / Chapter 3.2.4 --- Model Operation --- p.43 / Chapter 3.3 --- Instream Water Quality Modeling --- p.45 / Chapter 3.3.1 --- Description ofWASP5 --- p.46 / Chapter 3.3.2 --- Hydraulic Parameters --- p.47 / Chapter 3.3.3 --- Model Constants --- p.48 / Chapter 3.4 --- Description of Model Input Data --- p.49 / Chapter 3.4.1 --- Watershed Delineation --- p.49 / Chapter 3.4.2 --- Soil Data --- p.51 / Chapter 3.4.3 --- Rainfall Data --- p.52 / Chapter 3.4.4 --- Detection Landuse Changes --- p.53 / Chapter 3.4.4.1 --- Image Preprocessing --- p.54 / Chapter 3.4.4.2 --- Classification and Post-classification Analysis --- p.57 / Chapter 3.4.4.3 --- Assessment of Accuracy --- p.60 / Chapter 3.5 --- Scenario Modeling --- p.61 / Chapter CHAPTER FOUR - --- INTERFACING ARCVIE W GIS WITH WATER QUALITY MODEL / Chapter 4.1 --- Watershed Parameter Generator --- p.64 / Chapter 4.1.1 --- Topographic Analysis and Stream Network Definition --- p.65 / Chapter 4.1.2 --- Vectorization of Basin Geometries --- p.68 / Chapter 4.1.3 --- Computation of Basin Geometric Characteristics --- p.69 / Chapter 4.2 --- Nonpoint Source Pollution Loading Generator --- p.69 / Chapter 4.3 --- Instream Water Quality Calculator --- p.74 / Chapter CHAPTER FIVE- --- LANDUSE AND LAND COVER CHANGES ANALYSIS / Chapter 5.1 --- Framework for Analysis --- p.78 / Chapter 5.2 --- Landuse Changes During the Study Period --- p.82 / Chapter 5.2.1 --- Areal Landuse Changes --- p.82 / Chapter 5.2.2 --- Inter-category Landuse Changes --- p.86 / Chapter 5.2.2.1 --- Rural-to-urban Changes --- p.86 / Chapter 5.2.2.2 --- Rural-to-rural Changes --- p.87 / Chapter 5.2.3 --- Error matrix --- p.88 / Chapter 5.3 --- Spatial Pattern of Landuse and Land cover --- p.91 / Chapter 5.3.1 --- Urban Land --- p.92 / Chapter 5.3.2 --- Rural Areas --- p.94 / Chapter 5.4 --- Scenario Building --- p.96 / Chapter 5.5 --- Limitation of Landuse Classification based on Satellite Image Interpretation --- p.96 / Chapter 5.6 --- Summary --- p.98 / Chapter CHAPTER SIX - --- IMPACTS OF LANDUSE CHANGES ON NONPOINT SOURCE POLLUTION LOADING AND WATER QUALITY / Chapter 6.1 --- Impact of Landuse Changes on NPS Loading --- p.100 / Chapter 6.1.1 --- Identification of Curve Number --- p.100 / Chapter 6.1.2 --- Runoff and Areal Nonpoint Source Pollution Loadings --- p.101 / Chapter 6.1.3 --- Sensitivity of NPS Pollution Loading to Landuse Changes --- p.107 / Chapter 6.2 --- Instream Water Quality Analysis --- p.110 / Chapter 6.2.1 --- Downstream Variation of Water Quality --- p.111 / Chapter 6.2.2 --- Comparison with NWQC II --- p.114 / Chapter 6.3 --- Strategic Landuse Management --- p.117 / Chapter 6.4 --- Limitation of the Study --- p.118 / Chapter CHAPTER SEVEN - --- CONCLUSION / Chapter 7.1 --- Summary of Findings --- p.122 / Chapter 7.1.1 --- Landuse and Land Cover Changes --- p.122 / Chapter 7.1.2 --- GIS-based Water Quality Modeling --- p.123 / Chapter 7.1.3 --- Pollution Loading and Instream Water Quality --- p.124 / Chapter 7.2 --- Future Study --- p.125 / REFERENCES --- p.127

The environmental impact of agricultural activities on water quality was studied on two sub-watersheds of the L'Assomption river in Quebec, over a 3 year period. The sub-watersheds studied were the Saint Esprit (26.1 km 2) and Desrochers (17.9 km2). Development of a methodology and associated tools for targeting conservation activities and assessing the potential impacts of conservation practices was one of the study's components. A goal of this research was the development of a tool using NPS modelling capability and GIS tools. The ANSWERS 2000 model and SPANS GIS software were selected for integration. / Using the advanced SPANS operation and EASI script language, the ANSWERS 2000 model was integrated into the latest version of SPANS GIS (Explorer ver. 7). Integration of these two software packages provided assistance in creating and handling the extensive input and output data for models, evaluating of model output, and delineating of critical areas. A sensitivity analysis of the ANSWERS model was performed on thirteen parameters to determine their effects on runoff ANSWERS 2000 was found to be most sensitive to depth of soil horizon, silt and clay contents of soil texture, and solar radiation. Four years of runoff predictions by the model were analysed using observed data. Overall, the model was in good agreement with observed runoff in the Saint Esprit watershed, particularly in the years with above the average precipitation. The coefficient of (CP'A) between predicted and observed runoff values was 0.5 and 1.5 for 1994 and 1995, respectively. The model predictions of total cumulative runoff were 66.6% in 1994, 54.9% in 1995, 71.7% in 1996, and 42.4% in 1997, of measured cumulative runoff values.

A study was conducted to assess the efficiency of a constructed wetland for sediment and nutrient removal from a riverine source containing non-point source pollution (NPS) in a Nordic climate. The constructed wetland, built near the town of Mystic, Southern Quebec, consists of a sedimentation basin, a sinuous subsurface horizontal flow section and an open water body or pond that continuously receives up to 5% of Walbridge Creek. Flow into and through the system is controlled by gravity. There is a gate on the intake structure, which allows inflow into the wetland to be adjusted, along with three composite weirs; located at the outlet of each section of the wetland. Water samples were analyzed for orthophosphates (PO4), dissolved phosphorus (DP), total phosphorus (TP), ammonium (NH4+) and nitrates (NO3-) The study occurred from May to December 2003 and from May to December 2004. In 2003, there was a 33.6% reduction in TP load from intake to outlet with a retention rate of 2.23 g m-2 year-1. The greatest reduction in TP load during 2003 took place during the summer months (32.2%). In 2004, there was a further reduction of 42.8% in TP load from intake to outlet with a retention rate of 1.56 g m-2 year-1 compared to 2003. The largest reduction in TP load during the operational year of 2004 took place during the summer months (43.7%). Within the wetland, both the submerged flow section and open water basin showed similar and significant reductions of TP load in 2003 and 2004 annually and seasonally. Both annually and seasonally in 2003, NO3- showed no significant decrease in load from intake to outlet or within portions of the wetland. In 2004, there was a 22% annual load reduction from intake to outlet with a retention rate of 43.9 g m-2 year-1. The largest reduction in NO3- load during 2004 took place during the summer months (25.6%). Within the wetland, the submerged flow section showed the greatest reduction in NO3- concentrations annually and during the summer months of 2004. These results confirm the range of treatment efficiencies that can be achieved using a constructed wetland for NPS pollution in a Nordic climate.

The purpose of this study was to determine how much phosphorus could be lost from soils in Quebec. Samples of four soil series and 3 sediment samples from the St. Esprit watershed, Quebec, Canada were treated with KH2PO 4 solutions of 0, 50,100, and 500 mg kg--1 of soil. The relationship between water-extractable phosphorus (soluble phosphorus) and Mehlich III available phosphorus was determined at water: soil ratios 100:1, 200:1, 500:1. Measurements were made on a LACHAT QuickChem AE instrument (based on EPA method 365.3; USEPA, 1983) after 4 hours of shaking. More than 90% of the soluble phosphorus was released after 3 hours of shaking for all the soil samples and the sediment sample. Therefore, the shaking time for release of soluble P was set at 4 hours for all soil groups of the watershed. Mehlich III extractable phosphorus was also determined for each soil and sediment sample. Using a modified form of a well-known equation, it was possible to show that, with appropriate values for the constants, linear relationships exist between the logarithm of soluble phosphorus and the logarithm of Mehlich III extractable phosphorus at different water soil ratios. This was true for all soil groups and the sediment sample. Thus, given the soil type of a particular watershed, and using the linear relationship (isotherm) for that type, it becomes possible to predict the phosphorus yields from agricultural lands with reasonable confidence.

Stream samples were tested at 18 sites in three subwatersheds of the Upper White River for ammonia, nitrate, orthophosphate, atrazine, and diazinon. Nutrient results were tested with a general linear model and in linear regressions with selected landuse characteristics. A critical areas index for surface runoff of pollutants was created using a geographic information system. Comparisons were made between results obtained by Ball State University and by the Muncie Bureau of Water Quality and other outside laboratories. Most mean concentrations of nutrients were likely related to combinations of agricultural and residential landuse factors. Only concentrations of ammonia and orthophosphate were significantly related (a = 0.05) to any landuse characteristics. Atrazine levels were high in the spring, but decreased in the fall. Results suggest that improved or increased best management practices should be implemented in these subwatersheds to control non-point source pollution of the streams. / Department of Natural Resources and Environmental Management

A research project was undertaken to study the hydrology and water quality of a 26 km$ sp2$ intensive agricultural watershed over an 18 month period. Flow and precipitation data were used to establish hydrologic parameters for the watershed and to empirically model hydrologic processes. Water samples taken from the outlet of the watershed were analyzed for nitrate, phosphate, suspended sediment and atrazine. Water quality data were analyzed to establish temporal trends in pollutant concentration and load in the watercourse. / The measured time of concentration was found to be consistent with a mean of 6.89 hours for the 25 storms profiled. The time to peak was found to vary linearly with storm duration. The event recession constant was measured to be 0.9715. Regression analysis was performed on measured hydrologic properties. The strongest relationship was found between the percentage of rainfall appearing as runoff versus the sum of the 72 hour antecedent rainfall plus the storm rainfall. / Spring snowmelt was identified as a significant period of pollutant material export. All pollutant materials displayed seasonal variability in the export process. Temporal variability accounted for poor correlations between observed hydrologic and water quality parameters in the two seasons for which data were available. / Peak pollutant concentrations were associated with high flow events. Maximum observed concentrations for nitrate, phosphate, suspended sediment and atrazine were 8.6 mg/l, 0.478 mg/l, 0.7 g/l, and 8.06 ug/l respectively.

CAPES / Os corpos hídricos têm suas características afetadas pela poluição difusa, por meio do carreamento de poluentes pelo escoamento superficial nos eventos de chuvas ou também por despejos pontuais. Esta pesquisa foi realizada nas cavas do Parque das Águas em Pinhais/PR e teve por objetivo avaliar a qualidade das águas e sedimentos dos corpos hídricos e a sua correlação com a poluição difusa. Foram analisadas algumas variáveis físico-químicas, bacteriológicas e de compostos orgânicos HPAs e n-Alcanos em 6 pontos, que podem indicar possíveis alterações na qualidade desses corpos hídricos. Estas cavas deverão futuramente ser destinadas para uso de recreação de contato secundário, como pesca e esportes náuticos pela LEI No 189/87 - Pinhais, indicando que as águas dessas cavas devem atender a resolução CONAMA 357/05, que estabelece limites para parâmetros físico- químicos, biológicos e de espécies metálicas que possam causar danos à saúde e ao ambiente. Para embasar a discussão dos resultados para HPAs e espécies metálicas em sedimento, utilizou-se a resolução CONAMA 344/04. Os limites indicados pelas resoluções do CONAMA 357/05 e 344/04, são valores de segurança. Com base nos resultados obtidos, identificou-se a influência das chuvas nas concentrações das variáveis analisadas. Através da comparação dos resultados com a Resolução CONAMA 357/05 para água doce de classe 2, pôde ser constatado que os parâmetros salinidade, OD, turbidez, amônia, nitrito, nitrato estão de acordo com os limites impostos pela resolução, a DBO a para maioria dos pontos analisados apresentou-se dentro dos limites, porém em um dos pontos excedeu o limite. Para Coliformes termotolerantes, a maior parte dos pontos se apresentou dentro dos limites estabelecidos pela resolução. A variável Sulfeto não atende a CONAMA 357/05. Dos sete metais analisados em água cádmio e ferro apresentam-se acima do limite para o CONAMA 357/05. Os metais cobre, zinco, cádmio, níquel e chumbo em sedimentos estão dentro do limite da resolução CONAMA 344/04, mas em alguns pontos amostrados os HPAs indicaram contaminação por elementos de origem petrogênica quando confrontados com os limites indicados nesta mesma resolução. Para evitar que os limites sejam excedidos, visto que alguns dos pontos amostrados estão muito próximos, ou extrapolando os limites indicados, faz-se necessário evitar a entrada de poluente nas cavas do parque em questão, devido ao grande risco de perder a qualidade destes corpos hídricos e prejudicar a sua função para a sociedade. A pesquisa permitiu identificar que o incremento da carga poluente é potencializado pelo escoamento superficial das chuvas, inferindo desta forma, a necessidade do controle da poluição difusa para a área do parque. Uma das possíveis soluções seria a implantação de sistemas de wetlands construídos, que podem funcionar como barreiras para a entrada de poluentes, principalmente nas cavas mais próximas às estruturas viárias pavimentadas. / The water bodies have the characteristics affected by diffuse pollution through the drift of pollutants in the runoff from rain events or also by occasional evictions. This research was conducted in pools of the Water Park in Pinhais/PR and aimed to assess the quality of waters and sediments of water bodies and their correlation with diffuse pollution. The analyses from some physico-chemical, bacteriological and organic compounds PAHs and n-alkanes in 6 points, indicated possible changes in the quality of these water bodies. These pools will be designed for future use of secondary contact recreation such as fishing and water sports in the LAW 189/87 - Pinhais-PR, indicating that the water pools must answer these CONAMA Resolution 357/05, which sets limits for physical- chemical, biological and metal species that may cause damage to health and the environment. To support the discussion of the results for PAHs in sediment and metal species, is used the CONAMA Resolution 344/04. The limits given by CONAMA resolutions 357/05 and 344/04, are safety values. Based on these results, we identified the influence of rainfall in the concentrations of all variables. By comparing the results with CONAMA Resolution 357/05 for freshwater class 2, it might be noted that the parameters salinity, dissolved oxygen, turbidity, ammonia, nitrite, nitrate comply with the limits imposed by resolution, for the DBO Most points analyzed was within the limits, but in one of the exceeded limit. For Fecal coliform, most points are presented within the limits established by resolution. The variable sulfide does not meet CONAMA 357/05. Of the seven metals analyzed in water cadmium and iron are found above the ceiling for CONAMA 357/05. The metals copper, zinc, cadmium, nickel and lead in sediments are within the limit of CONAMA Resolution 344/04, but in some sampling sites indicated PAH contamination source elements petrogenic when confronted with the limits specified in this same resolution. To avoid the exceeding the limits, since some of the points are very close, or extrapolating the limits, it is necessary prevent the entry of polluting the pools of the park in question, due to the high risk of losing the quality of these bodies water and impair its function for society. The research identified that the increase in pollution load is powered by the runoff of rainfall, implying thus the need for control of diffuse pollution to the park area. One of the possible solutions would be the deployment of constructed wetlands, which can act as barriers to the entry of pollutants, mainly pools nearest paved road structures.

CAPES / Os corpos hídricos têm suas características afetadas pela poluição difusa, por meio do carreamento de poluentes pelo escoamento superficial nos eventos de chuvas ou também por despejos pontuais. Esta pesquisa foi realizada nas cavas do Parque das Águas em Pinhais/PR e teve por objetivo avaliar a qualidade das águas e sedimentos dos corpos hídricos e a sua correlação com a poluição difusa. Foram analisadas algumas variáveis físico-químicas, bacteriológicas e de compostos orgânicos HPAs e n-Alcanos em 6 pontos, que podem indicar possíveis alterações na qualidade desses corpos hídricos. Estas cavas deverão futuramente ser destinadas para uso de recreação de contato secundário, como pesca e esportes náuticos pela LEI No 189/87 - Pinhais, indicando que as águas dessas cavas devem atender a resolução CONAMA 357/05, que estabelece limites para parâmetros físico- químicos, biológicos e de espécies metálicas que possam causar danos à saúde e ao ambiente. Para embasar a discussão dos resultados para HPAs e espécies metálicas em sedimento, utilizou-se a resolução CONAMA 344/04. Os limites indicados pelas resoluções do CONAMA 357/05 e 344/04, são valores de segurança. Com base nos resultados obtidos, identificou-se a influência das chuvas nas concentrações das variáveis analisadas. Através da comparação dos resultados com a Resolução CONAMA 357/05 para água doce de classe 2, pôde ser constatado que os parâmetros salinidade, OD, turbidez, amônia, nitrito, nitrato estão de acordo com os limites impostos pela resolução, a DBO a para maioria dos pontos analisados apresentou-se dentro dos limites, porém em um dos pontos excedeu o limite. Para Coliformes termotolerantes, a maior parte dos pontos se apresentou dentro dos limites estabelecidos pela resolução. A variável Sulfeto não atende a CONAMA 357/05. Dos sete metais analisados em água cádmio e ferro apresentam-se acima do limite para o CONAMA 357/05. Os metais cobre, zinco, cádmio, níquel e chumbo em sedimentos estão dentro do limite da resolução CONAMA 344/04, mas em alguns pontos amostrados os HPAs indicaram contaminação por elementos de origem petrogênica quando confrontados com os limites indicados nesta mesma resolução. Para evitar que os limites sejam excedidos, visto que alguns dos pontos amostrados estão muito próximos, ou extrapolando os limites indicados, faz-se necessário evitar a entrada de poluente nas cavas do parque em questão, devido ao grande risco de perder a qualidade destes corpos hídricos e prejudicar a sua função para a sociedade. A pesquisa permitiu identificar que o incremento da carga poluente é potencializado pelo escoamento superficial das chuvas, inferindo desta forma, a necessidade do controle da poluição difusa para a área do parque. Uma das possíveis soluções seria a implantação de sistemas de wetlands construídos, que podem funcionar como barreiras para a entrada de poluentes, principalmente nas cavas mais próximas às estruturas viárias pavimentadas. / The water bodies have the characteristics affected by diffuse pollution through the drift of pollutants in the runoff from rain events or also by occasional evictions. This research was conducted in pools of the Water Park in Pinhais/PR and aimed to assess the quality of waters and sediments of water bodies and their correlation with diffuse pollution. The analyses from some physico-chemical, bacteriological and organic compounds PAHs and n-alkanes in 6 points, indicated possible changes in the quality of these water bodies. These pools will be designed for future use of secondary contact recreation such as fishing and water sports in the LAW 189/87 - Pinhais-PR, indicating that the water pools must answer these CONAMA Resolution 357/05, which sets limits for physical- chemical, biological and metal species that may cause damage to health and the environment. To support the discussion of the results for PAHs in sediment and metal species, is used the CONAMA Resolution 344/04. The limits given by CONAMA resolutions 357/05 and 344/04, are safety values. Based on these results, we identified the influence of rainfall in the concentrations of all variables. By comparing the results with CONAMA Resolution 357/05 for freshwater class 2, it might be noted that the parameters salinity, dissolved oxygen, turbidity, ammonia, nitrite, nitrate comply with the limits imposed by resolution, for the DBO Most points analyzed was within the limits, but in one of the exceeded limit. For Fecal coliform, most points are presented within the limits established by resolution. The variable sulfide does not meet CONAMA 357/05. Of the seven metals analyzed in water cadmium and iron are found above the ceiling for CONAMA 357/05. The metals copper, zinc, cadmium, nickel and lead in sediments are within the limit of CONAMA Resolution 344/04, but in some sampling sites indicated PAH contamination source elements petrogenic when confronted with the limits specified in this same resolution. To avoid the exceeding the limits, since some of the points are very close, or extrapolating the limits, it is necessary prevent the entry of polluting the pools of the park in question, due to the high risk of losing the quality of these bodies water and impair its function for society. The research identified that the increase in pollution load is powered by the runoff of rainfall, implying thus the need for control of diffuse pollution to the park area. One of the possible solutions would be the deployment of constructed wetlands, which can act as barriers to the entry of pollutants, mainly pools nearest paved road structures.

No description available.

No description available.