<p><font face="Times New Roman"><font face="Times New Roman"> <p align="left">The research problem for this study is the limited and unsuccessful implementation of the IWRM concept. This thesis has argued that comprehensive assessment of physical and socioeconomic conditions is essential to provide explanation on factors that limit the successful execution of the IWRM approach. It has further argued that the local IWRM works as proxy for full and successful implementation of the IWRM approach. To contextualise this thesis, the prevailing physical and socioeconomic factors in Malawi in relation to current management and usage of water resources were explained. With 1,321m per year, this study showed that Malawi is a physically water stressed country but not physically water scarce country although economically it is a water scarce country. This novelty is against some literature that present Malawi as a water abundant country. Again, this study showed that executing a full and successful IWRM in Malawi remains a challenge because of the prevailing socioeconomic situation in terms of water policies, water laws, institutions and management instruments. These aspects have not been reformed and harmonised to facilitate a successful operation of the IWRM approach. The main water-related problem in Malawi is the mismanagement of the available water resources. This is largely due to the lack of implementing management approaches which can generate systematic data for practical assessment of water resources to guide the coordinated procedure among water stakeholders working in catchments. This lack of implementing a coordinated management approach commonly known as integrated water resources management (IWRM) can be attributed to various reasons that include i) lack of comprehensive assessment of factors that can explain lack of successful IWRM implementation at catchment level and ii) lack of methods to demonstrate data generation and analysis on quantity, quality and governance of water that show practical operation of IWRM at community level using groundwater as a showcase among others. This study revealed that introducing local IWRM requires a prior knowledge of the evolution and role of the full IWRM concept in the international water policy which aimed at addressing broader developmental objectives. Globally, the current status of the IWRM concept has potential to address such broader developmental objectives, but sustaining IWRM projects where they have been piloted showed slow progress. Basing<font face="Times New Roman">&nbsp / on the factors that slow such a progress, local IWRM approach has emerged as a proxy to execute the full IWRM as demonstrated in chapter 8 in this thesis. However, the observed lack of sustainable resources to fund continual functioning of local IWRM activities will defeat its potential solution to water management challenges. The main threat for sustainable local IWRM activities is the tendency of national governments to decentralise roles and responsibilities to local governments and communities without the accompanying financial resources to enable the implementation of the local participation, investments and initiatives at local level. If this tendency could be reversed, the contribution by local IWRM towards solving management problems in the water sector will be enormous. Chapter four has provided the general case-study approach used in this study in terms of research design, data collection methods, data analysis methods, ethical consideration and limitation of the current study within the context of water resource management with a focus on groundwater management. Using geologic map, satellite images, photographs and hydrogeologic conceptual model, the following results emerged: 1) that the Upper Limphasa River catchment has fractured rock aquifer with limited permeability and storage capacity / 2) The topographic nature and north-south strikes of the lineaments explained the north-south flow direction of groundwater in the catchment / 3) The drainage system observed in the Kandoli and Kaning&rsquo / ina Mountains to the east and west of the Upper Limphasa River catchment respectively (Fig. 5.1 / Fig.5.2) formed a groundwater recharge boundary / 4) The regional faults in the same mountains (Fig. 5.1 / Fig.5.2) formed structural boundary as well as hydrogeologic boundary which controlled flow direction of the groundwater / 5) the hydrogeologic conceptual model showed the existence of the forested weathered bedrock in the upland areas of the entire catchment which formed no-flow boundary and groundwater divide thereby controlling the water flow direction downwards (Fig. 5.9) / 6) The major agricultural commercial activities existed in Lower Limphasa catchment while only subsistence farming existed in Upper Limphasa catchment. This knowledge and visualization from the map (Fig. 5.3) and conceptual model (Fig.5.9) showe interactions between upland and lowland areas and the role of physical factors in controlling groundwater flow direction in the catchment. It also provided the enlightenment on implications of socioeconomic farming activities on water management. These insights enabled this study to recommend the need for expedited implementation of holistic effective management for sustainable water utilization. <font face="Times New Roman">Using different physical factors, water scarcity indices and methodologies, this study showed that Malawi is a physically water stressed as well as an economic water scarce country. This novelty is against some literature that present Malawi as a water abundant country. Again, despite the high proportion (85%) of Malawians relying on groundwater resource, groundwater availability (storage in km 6.10) compared to other countries within SADC and Africa. Given the complexity of</font><font face="Times New Roman"> groundwater abstraction, the available groundwater for use is further reduced for Malawians who depend on such a resource for their domestic and productive livelihoods. Such insights provided the basis for discussing the need for IWRM. Although daily statistics on groundwater demand (i: 21.20 litres / 116.91 litres / 80,550.99 litres), use (ii: 16.8 litres / 92.55 litres / 63,766.95 litres) and abstracted but not used (iii: 4.4 / 24.36 / 16,784.04 litres) were relatively low per person, per household and per sub-catchment respectively, such statistics when calculated on monthly basis (i. Demand: 636 litres / 3,507.30 litres / 2,416,529.70 litres / ii.Use:504 litres / 2,776.5 litres / 1, 913, 008.5 litres iii. Abstracted but not used: 132 litres / 730 litres / 503, 521.2) / and on yearly basis (i. Demand: 7,632 litres / 42,087.6 litres / 28,998,356.4 litres / ii. Use: 6,048 litres / 33,318 litres / 22, 956, 102 litres / iii: Abstracted but not used: 1,584 litres / 8,769.6 litres / 6,042,254.4 litres) per person, per household and per sub-catchment provided huge amount of groundwater (Table 6.5). Given the limited storage capacity of fractured rock aquifer in the basement complex geology, the monthly and yearly groundwater demand and use on one hand and abstracted but not used on the other was considered enormous. With the population growth rate of 2.8 for Nkhata Bay (NSO, 2009) and the observed desire to intensify productive livelihoods activities coupled with expected negative effects of climate change, the need to implement IWRM approach for such groundwater resource in the study catchment remains imperative and is urgently needed. In addition to identifying and describing factors that explain the limited groundwater availability in the study catchment, the study developed a methodology for calculating groundwater demand, use and unused at both households and sub-catchment levels. This methodology provided step-by-step procedure for collecting data on groundwater demand and use as a tool that would improve availability of data on groundwater. Implications of such results for IWRM in similar environments were discussed. Despite<font face="Times New Roman">&nbsp / the time-consuming procedure involved in using the developed methodology, the calculations are simple and interpretation of results is easily understood among various stakeholders. Hence, such an approach is recommended for the IWRM approach which requires stakeholders from various disciplines to interact and collaborate. Nonetheless, this recommends the use of this method as its further refinement is being sought. The analysis on groundwater quality has shown that the dominant water type in the aquifers of Upper Limphasa catchment was Ca-HCO had shallow, fresh groundwater with recent recharged aquifer. Analyses on</font><font face="Times New Roman"> physicochemical parameters revealed that none of the sampled boreholes (BHs) and protected shallow dug wells (PSWs) had physical or chemical concentration levels of health concern when such levels were compared with 2008-World Health Organisation (WHO) guidelines and 2005-Malawi Bureau of Standards (MBS). Conversely, although the compliance with 2008-WHO and 2005-MBS of pathogenic bacteria (E.coli) in BHs water was 100% suggesting that water from BHs had low risk and free from bacteriological contamination, water from PSWs showed 0% compliance with 2008- WHO and 2005-MBS values implying high risk to human health. The overall assessment on risk to health classification showed that PSWs were risky sources to supply potable water, hence the need to implement strategies that protect groundwater. On the basis of such findings, the analysis in this study demonstrated the feasibility of using IWRM approach as a platform for implementing environmental and engineering interventions through education programmes to create and raise public awareness on groundwater protection and on the need for collaborative efforts to implement protective measures for their drinking water sources. The use of different analytical methods which were applied to identify the exact sources of the observed contaminants in the PSWs proved futile. Therefore, this study concluded that rolling-out PSWs either as improved or safe sources of drinking water requires further detailed investigations. However, this research recommended using rapid assessment of drinking water-quality (RADWQ) methods for assessing the quality of groundwater sources for drinking. Despite the study area being in the humid climatic region with annual rainfall above 1,000 mm, many of the physical factors were not favourable for availability of more groundwater in the aquifers. Such observation provided compelling evidence in this<font face="Times New Roman">&nbsp / study to commend the local IWRM as a proxy for the full IWRM implementation for sustainable utilization of such waters. Although institutional arrangements, water laws and water policy were found problematic to facilitate a successful implementation of full IWRM at national level in Malawi, this thesis demonstrated that local institutional arrangements, coordination among institutions, data collection efforts by local community members (active participation), self-regulation among local community committees were favourable conditions for a successful local IWRM in the Upper Limphasa River catchment. This research recommends continuation of such local participation, investment and initiatives as proxy for the full and successful IWRM beyond the study catchment. However, the observed lack of financial resource from central government to facilitates local IWRM activities were seen as counterproductive. In addition, this thesis recommended further studies which should aim at improving some observed negative implications of self-regulations on community members and the limited decentralisation elements from the Department of Water Development. Finally, one of the contributions from this study is the scientific value in using different methods to assess the quality of groundwater as presented in chapter 7. The second value is the demonstration of applying practical techniques to evaluate factors that explain the amount of groundwater storage in the aquifers that can be understood by water scientists, water users, water developers and water managers to implement IWRM collaboratively using groundwater as a showcase. The third contribution is the provision of the procedure to systematically generate data on demand (abstraction) and use of groundwater in unmetered rural areas which has the potential to guide water allocation process in the catchment. Fourthly, the thesis has provided a hydrogeologic conceptual model for the first time for Limphasa River catchment to be used as a visual tool for planning and developing management practices and addressing current water problems. Fifthly, the study has shown how local IWRM works at community level as a proxy for the full implementation of IWRM despite the absence of Catchment Management Agencies. The last contribution is the dissemination of results from this study made through publications and conference presentations as outlined in the appendix.</font></font></font></font></p> </font></font></p>

<p><font face="Times New Roman"><font face="Times New Roman"> <p align="left">The research problem for this study is the limited and unsuccessful implementation of the IWRM concept. This thesis has argued that comprehensive assessment of physical and socioeconomic conditions is essential to provide explanation on factors that limit the successful execution of the IWRM approach. It has further argued that the local IWRM works as proxy for full and successful implementation of the IWRM approach. To contextualise this thesis, the prevailing physical and socioeconomic factors in Malawi in relation to current management and usage of water resources were explained. With 1,321m per year, this study showed that Malawi is a physically water stressed country but not physically water scarce country although economically it is a water scarce country. This novelty is against some literature that present Malawi as a water abundant country. Again, this study showed that executing a full and successful IWRM in Malawi remains a challenge because of the prevailing socioeconomic situation in terms of water policies, water laws, institutions and management instruments. These aspects have not been reformed and harmonised to facilitate a successful operation of the IWRM approach. The main water-related problem in Malawi is the mismanagement of the available water resources. This is largely due to the lack of implementing management approaches which can generate systematic data for practical assessment of water resources to guide the coordinated procedure among water stakeholders working in catchments. This lack of implementing a coordinated management approach commonly known as integrated water resources management (IWRM) can be attributed to various reasons that include i) lack of comprehensive assessment of factors that can explain lack of successful IWRM implementation at catchment level and ii) lack of methods to demonstrate data generation and analysis on quantity, quality and governance of water that show practical operation of IWRM at community level using groundwater as a showcase among others. This study revealed that introducing local IWRM requires a prior knowledge of the evolution and role of the full IWRM concept in the international water policy which aimed at addressing broader developmental objectives. Globally, the current status of the IWRM concept has potential to address such broader developmental objectives, but sustaining IWRM projects where they have been piloted showed slow progress. Basing<font face="Times New Roman">&nbsp / on the factors that slow such a progress, local IWRM approach has emerged as a proxy to execute the full IWRM as demonstrated in chapter 8 in this thesis. However, the observed lack of sustainable resources to fund continual functioning of local IWRM activities will defeat its potential solution to water management challenges. The main threat for sustainable local IWRM activities is the tendency of national governments to decentralise roles and responsibilities to local governments and communities without the accompanying financial resources to enable the implementation of the local participation, investments and initiatives at local level. If this tendency could be reversed, the contribution by local IWRM towards solving management problems in the water sector will be enormous. Chapter four has provided the general case-study approach used in this study in terms of research design, data collection methods, data analysis methods, ethical consideration and limitation of the current study within the context of water resource management with a focus on groundwater management. Using geologic map, satellite images, photographs and hydrogeologic conceptual model, the following results emerged: 1) that the Upper Limphasa River catchment has fractured rock aquifer with limited permeability and storage capacity / 2) The topographic nature and north-south strikes of the lineaments explained the north-south flow direction of groundwater in the catchment / 3) The drainage system observed in the Kandoli and Kaning&rsquo / ina Mountains to the east and west of the Upper Limphasa River catchment respectively (Fig. 5.1 / Fig.5.2) formed a groundwater recharge boundary / 4) The regional faults in the same mountains (Fig. 5.1 / Fig.5.2) formed structural boundary as well as hydrogeologic boundary which controlled flow direction of the groundwater / 5) the hydrogeologic conceptual model showed the existence of the forested weathered bedrock in the upland areas of the entire catchment which formed no-flow boundary and groundwater divide thereby controlling the water flow direction downwards (Fig. 5.9) / 6) The major agricultural commercial activities existed in Lower Limphasa catchment while only subsistence farming existed in Upper Limphasa catchment. This knowledge and visualization from the map (Fig. 5.3) and conceptual model (Fig.5.9) showe interactions between upland and lowland areas and the role of physical factors in controlling groundwater flow direction in the catchment. It also provided the enlightenment on implications of socioeconomic farming activities on water management. These insights enabled this study to recommend the need for expedited implementation of holistic effective management for sustainable water utilization. <font face="Times New Roman">Using different physical factors, water scarcity indices and methodologies, this study showed that Malawi is a physically water stressed as well as an economic water scarce country. This novelty is against some literature that present Malawi as a water abundant country. Again, despite the high proportion (85%) of Malawians relying on groundwater resource, groundwater availability (storage in km 6.10) compared to other countries within SADC and Africa. Given the complexity of</font><font face="Times New Roman"> groundwater abstraction, the available groundwater for use is further reduced for Malawians who depend on such a resource for their domestic and productive livelihoods. Such insights provided the basis for discussing the need for IWRM. Although daily statistics on groundwater demand (i: 21.20 litres / 116.91 litres / 80,550.99 litres), use (ii: 16.8 litres / 92.55 litres / 63,766.95 litres) and abstracted but not used (iii: 4.4 / 24.36 / 16,784.04 litres) were relatively low per person, per household and per sub-catchment respectively, such statistics when calculated on monthly basis (i. Demand: 636 litres / 3,507.30 litres / 2,416,529.70 litres / ii.Use:504 litres / 2,776.5 litres / 1, 913, 008.5 litres iii. Abstracted but not used: 132 litres / 730 litres / 503, 521.2) / and on yearly basis (i. Demand: 7,632 litres / 42,087.6 litres / 28,998,356.4 litres / ii. Use: 6,048 litres / 33,318 litres / 22, 956, 102 litres / iii: Abstracted but not used: 1,584 litres / 8,769.6 litres / 6,042,254.4 litres) per person, per household and per sub-catchment provided huge amount of groundwater (Table 6.5). Given the limited storage capacity of fractured rock aquifer in the basement complex geology, the monthly and yearly groundwater demand and use on one hand and abstracted but not used on the other was considered enormous. With the population growth rate of 2.8 for Nkhata Bay (NSO, 2009) and the observed desire to intensify productive livelihoods activities coupled with expected negative effects of climate change, the need to implement IWRM approach for such groundwater resource in the study catchment remains imperative and is urgently needed. In addition to identifying and describing factors that explain the limited groundwater availability in the study catchment, the study developed a methodology for calculating groundwater demand, use and unused at both households and sub-catchment levels. This methodology provided step-by-step procedure for collecting data on groundwater demand and use as a tool that would improve availability of data on groundwater. Implications of such results for IWRM in similar environments were discussed. Despite<font face="Times New Roman">&nbsp / the time-consuming procedure involved in using the developed methodology, the calculations are simple and interpretation of results is easily understood among various stakeholders. Hence, such an approach is recommended for the IWRM approach which requires stakeholders from various disciplines to interact and collaborate. Nonetheless, this recommends the use of this method as its further refinement is being sought. The analysis on groundwater quality has shown that the dominant water type in the aquifers of Upper Limphasa catchment was Ca-HCO had shallow, fresh groundwater with recent recharged aquifer. Analyses on</font><font face="Times New Roman"> physicochemical parameters revealed that none of the sampled boreholes (BHs) and protected shallow dug wells (PSWs) had physical or chemical concentration levels of health concern when such levels were compared with 2008-World Health Organisation (WHO) guidelines and 2005-Malawi Bureau of Standards (MBS). Conversely, although the compliance with 2008-WHO and 2005-MBS of pathogenic bacteria (E.coli) in BHs water was 100% suggesting that water from BHs had low risk and free from bacteriological contamination, water from PSWs showed 0% compliance with 2008- WHO and 2005-MBS values implying high risk to human health. The overall assessment on risk to health classification showed that PSWs were risky sources to supply potable water, hence the need to implement strategies that protect groundwater. On the basis of such findings, the analysis in this study demonstrated the feasibility of using IWRM approach as a platform for implementing environmental and engineering interventions through education programmes to create and raise public awareness on groundwater protection and on the need for collaborative efforts to implement protective measures for their drinking water sources. The use of different analytical methods which were applied to identify the exact sources of the observed contaminants in the PSWs proved futile. Therefore, this study concluded that rolling-out PSWs either as improved or safe sources of drinking water requires further detailed investigations. However, this research recommended using rapid assessment of drinking water-quality (RADWQ) methods for assessing the quality of groundwater sources for drinking. Despite the study area being in the humid climatic region with annual rainfall above 1,000 mm, many of the physical factors were not favourable for availability of more groundwater in the aquifers. Such observation provided compelling evidence in this<font face="Times New Roman">&nbsp / study to commend the local IWRM as a proxy for the full IWRM implementation for sustainable utilization of such waters. Although institutional arrangements, water laws and water policy were found problematic to facilitate a successful implementation of full IWRM at national level in Malawi, this thesis demonstrated that local institutional arrangements, coordination among institutions, data collection efforts by local community members (active participation), self-regulation among local community committees were favourable conditions for a successful local IWRM in the Upper Limphasa River catchment. This research recommends continuation of such local participation, investment and initiatives as proxy for the full and successful IWRM beyond the study catchment. However, the observed lack of financial resource from central government to facilitates local IWRM activities were seen as counterproductive. In addition, this thesis recommended further studies which should aim at improving some observed negative implications of self-regulations on community members and the limited decentralisation elements from the Department of Water Development. Finally, one of the contributions from this study is the scientific value in using different methods to assess the quality of groundwater as presented in chapter 7. The second value is the demonstration of applying practical techniques to evaluate factors that explain the amount of groundwater storage in the aquifers that can be understood by water scientists, water users, water developers and water managers to implement IWRM collaboratively using groundwater as a showcase. The third contribution is the provision of the procedure to systematically generate data on demand (abstraction) and use of groundwater in unmetered rural areas which has the potential to guide water allocation process in the catchment. Fourthly, the thesis has provided a hydrogeologic conceptual model for the first time for Limphasa River catchment to be used as a visual tool for planning and developing management practices and addressing current water problems. Fifthly, the study has shown how local IWRM works at community level as a proxy for the full implementation of IWRM despite the absence of Catchment Management Agencies. The last contribution is the dissemination of results from this study made through publications and conference presentations as outlined in the appendix.</font></font></font></font></p> </font></font></p>

Mercury (Hg)-contaminated freshwater fisheries are a global toxicological concern. Previous research suggests that the slow release of Hg in runoff from upland soils may delay the recovery of Hg-contaminated aquatic systems. Four complementary studies were undertaken in a small boreal Shield headwater catchment as part of the Mercury Experiment to Assess Atmospheric Loading in Canada and the U.S. (METAALICUS) to assess the controls on the retention and release of historically-deposited Hg (ambient Hg) and newly-deposited (spike Hg) in the soil landscape. In the first study, hydrometric and GIS-based methods were used to quantify thresholds in terrestrial water storage and their relationship to observed rainfall-runoff response. It was found that event-scale hydrologic response displayed a threshold relationship with antecedent storage in the terminal depression and predictions of event runoff improved when storage excesses from upslope depressions were explicitly routed through the catchment. In the second study, it was shown that the dominant source of ambient Hg to the lake was likely derived from shallow soil-water flowing through the lower, well-humified organic soil horizon. Throughout the catchment, ambient Hg to soil organic carbon (SOC) ratios increased with depth and the experimentally-applied spike Hg was concentrated in the surface litter layer, suggesting that the vertical redistribution of Hg in the soil profile is a function of the rate of decomposition of SOC. In the third study, canopy type was found to be a good predictor of ambient Hg and spike Hg stocks in the lower organic horizon, while drainage conditions were not, suggesting that vertical fluxes of Hg dominate over lateral fluxes in topographically-complex landscapes. Lastly, it was shown that catchment discharge, antecedent depression storage and antecedent precipitation were the best predictors of dissolved organic carbon (DOC), ambient Hg and spike Hg concentrations in catchment runoff. A comparison of DOC, ambient Hg and spike Hg dynamics for two storm events showed that distinct shifts occurred in the concentration-discharge relationship as a result of differences in antecedent moisture conditions. Combined, the results of the four studies demonstrate the need to incorporate hydrological, biogeochemical and landscape controls into predictive models of terrestrial-aquatic Hg export.

Mercury (Hg)-contaminated freshwater fisheries are a global toxicological concern. Previous research suggests that the slow release of Hg in runoff from upland soils may delay the recovery of Hg-contaminated aquatic systems. Four complementary studies were undertaken in a small boreal Shield headwater catchment as part of the Mercury Experiment to Assess Atmospheric Loading in Canada and the U.S. (METAALICUS) to assess the controls on the retention and release of historically-deposited Hg (ambient Hg) and newly-deposited (spike Hg) in the soil landscape. In the first study, hydrometric and GIS-based methods were used to quantify thresholds in terrestrial water storage and their relationship to observed rainfall-runoff response. It was found that event-scale hydrologic response displayed a threshold relationship with antecedent storage in the terminal depression and predictions of event runoff improved when storage excesses from upslope depressions were explicitly routed through the catchment. In the second study, it was shown that the dominant source of ambient Hg to the lake was likely derived from shallow soil-water flowing through the lower, well-humified organic soil horizon. Throughout the catchment, ambient Hg to soil organic carbon (SOC) ratios increased with depth and the experimentally-applied spike Hg was concentrated in the surface litter layer, suggesting that the vertical redistribution of Hg in the soil profile is a function of the rate of decomposition of SOC. In the third study, canopy type was found to be a good predictor of ambient Hg and spike Hg stocks in the lower organic horizon, while drainage conditions were not, suggesting that vertical fluxes of Hg dominate over lateral fluxes in topographically-complex landscapes. Lastly, it was shown that catchment discharge, antecedent depression storage and antecedent precipitation were the best predictors of dissolved organic carbon (DOC), ambient Hg and spike Hg concentrations in catchment runoff. A comparison of DOC, ambient Hg and spike Hg dynamics for two storm events showed that distinct shifts occurred in the concentration-discharge relationship as a result of differences in antecedent moisture conditions. Combined, the results of the four studies demonstrate the need to incorporate hydrological, biogeochemical and landscape controls into predictive models of terrestrial-aquatic Hg export.

In recent years there has been a growing interest in the contemporary floodplain environment which has come from a number of fields including civil engineering, hydrology, geomorphology and ecology. A major advance in civil engineering has been the development of two-dimensional hydraulic models capable of a high degree of spatial representation. These models were originally developed for engineering applications although recent developments, such as their application to longer reach lengths, mean that these models are very powerful predictive tools with potential for application in many different fields. Two-dimensional floodplain hydraulic models can be viewed as a platform for further development through the incorporation of additional components to represent specific processes. For the case of the application of these models in hydrology, whilst the models provide a good representation of floodplain processes in a hydraulic context, catchment hydrology is essentially treated as a black box. The only input to the system is the upstream input hydrograph (occasionally rainfall over the floodplain surface and tributary inflows are included) and output only occurs at the downstream boundary. The floodplain is assumed to be impermeable and any input from the hillslopes bordering the reach is ignored. This investigation examines the significance of contributions to the floodplain from the hillslopes bordering the reach. In order to do this, the zero flux boundary condition at the hillslope-floodplain interface is relaxed. A two-dimensional floodplain inundation model, RMA-2, is set up for a 14 km reach of the River Culm in Devon. A distributed hillslope hydrology model, VSAS3 is set up for a section of the hillslopes bordering the reach. This model is coupled to RMA-2 using a simple external coupling mechanism whereby water produced by VSAS3 is applied to elements along the edge of the RMA- 2 finite element mesh. A sensitivity analysis is carried out using this coupled scheme to identify some of the range of hillslope environments which may contribute a significant volume of lateral inflow to the floodplain. Five key hillslope parameters are selected and altered over a range of values. It has been shown that hillslope inflows can have a significant effect on the predictions made by RMA-2, both in terms of changes to the predicted output hydrograph and localised changes in depth and inundation extent. It has also been shown that the timing of the hillslope inflow peak relative to the arrival of the floodwave from upstream is of great importance. The addition of inflows has also been found to affect the calibration of the floodplain inundation model.

京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第19298号 / 工博第4095号 / 新制||工||1631(附属図書館) / 32300 / 京都大学大学院工学研究科都市環境工学専攻 / (主査)教授 米田 稔, 教授 田中 宏明, 准教授 島田 洋子 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DGAM

Soil moisture is a key state variable that controls runoff formation, infiltration and partitioning of radiation into latent and sensible heat. However, the experimental characterisation of near surface soil moisture patterns and their controls on runoff formation remains a challenge. This subject was one aspect of the BMBF-funded OPAQUE project (operational discharge and flooding predictions in head catchments). As part of that project the focus of this dissertation is on: (1) testing the methodology and feasibility of the Spatial TDR technology in producing soil moisture profiles along TDR probes, including an inversion technique of the recorded signal in heterogeneous field soils, (2) the analysis of spatial variability and temporal dynamics of soil moisture at the field scale including field experiments and hydrological modelling, (3) the application of models of different complexity for understanding soil moisture dynamics and its importance for runoff generation as well as for improving the prediction of runoff volumes. To fulfil objective 1, several laboratory experiments were conducted to understand the influence of probe rod geometry and heterogeneities in the sampling volume under different wetness conditions. This includes a detailed analysis on how these error sources affect retrieval of soil moisture profiles in soils. Concerning objective 2 a sampling strategy of two TDR clusters installed in the head water of the Wilde Weißeritz catchment (Eastern Ore Mountains, Germany) was used to investigate how well “the catchment state” can be characterised by means of distributed soil moisture data observed at the field scale. A grassland site and a forested site both located on gentle slopes were instrumented with two Spatial TDR clusters that consist of up to 39 TDR probes. Process understanding was gained by modelling the interaction of evapotranspiration and soil moisture with the hydrological process model CATFLOW. A field scale irrigation experiment was carried out to investigate near subsurface processes at the hillslope scale. The interactions of soil moisture and runoff formation were analysed using discharge data from three nested catchments: the Becherbach with a size of 2 km², the Rehefeld catchment (17 km²) and the superordinate Ammelsdorf catchment (49 km²). Statistical analyses including observations of pre-event runoff, soil moisture and different rainfall characteristics were employed to predict stream flow volume. On the different scales a strong correlation between the average soil moisture and the runoff coefficients of rainfall-runoff events could be found, which almost explains equivalent variability as the pre-event runoff. Furthermore, there was a strong correlation between surface soil moisture and subsurface wetness with a hysteretic behaviour between runoff soil moisture. To fulfil objective 3 these findings were used in a generalised linear model (GLM) analysis which combines state variables describing the catchments antecedent wetness and variables describing the meteorological forcing in order to predict event runoff coefficients. GLM results were compared to simulations with the catchment model WaSiM ETH. Hereby were the model results of the GLMs always better than the simulations with WaSiM ETH. The GLM analysis indicated that the proposed sampling strategy of clustering TDR probes in typical functional units is a promising technique to explore soil moisture controls on runoff generation and can be an important link between the scales. Long term monitoring of such sites could yield valuable information for flood warning and forecasting by identifying critical soil moisture conditions for the former and providing a better representation of the initial moisture conditions for the latter. / Abflussentwicklung, Infiltration und die Umverteilung von Strahlung in latenten und sensiblen Wärmestrom werden maßgeblich durch die Bodenfeuchte der vadosen Zone gesteuert. Trotz allem, gibt s wenig Arbeiten die sich mit der experimentellen Charakterisierung der Bodenfeuchteverteilung und ihre Auswirkung auf die Abflussbildung beschäftigen. Der Fokus dieser Dissertation wurde darauf ausgerichtet: (1) die Methode des Spatial TDR und deren Anwendbarkeit einschließlich der Inversion des TDR Signals in heterogenen Böden zu prüfen, (2) die Analyse der räumlichen und zeitlichen Dynamik der Bodenfeuchte auf der Feldskala einschließlich Feldexperimenten und hydrologischer Modellierung, (3) der Aufbau verschiedener Modellanwendungen unterschiedlicher Komplexität um die Bodenfeuchtedynamiken und die Abflussentwicklung zu verstehen und die Vorhersage des Abflussvolumens zu verbessern. Um die Zielsetzung 1 zu erreichen, wurden verschiedene Laborversuche durchgeführt. Hierbei wurde der Einfluss der Sondenstabgeometrie und verschiedener Heterogenitäten im Messvolumen bei verschiedenen Feuchtegehalten untersucht. Dies beinhaltete eine detaillierte Analyse wie diese Fehlerquellen die Inversion des Bodenfeuchteprofils beeinflussen. Betreffend der Zielsetzung 2, wurden 2 TDR-Cluster in den Quellgebieten der Wilden Weißeritz installiert (Osterzgebirge) und untersucht, wie gut der Gebietszustand mit räumlich hochaufgelösten Bodenfeuchtedaten der Feldskala charakterisiert werden kann. Um die Interaktion zwischen Evapotranspiration und Bodenfeuchte zu untersuchen wurde das hydrologische Prozessmodell CATFLOW angewendet. Ein Beregnungsversuch wurde durchgeführt um die Zwischenabflussprozesse auf der Hangskala zu verstehen. Die Interaktion zwischen Bodenfeuchte und Abflussentwicklung wurde anhand von drei einander zugeordneten Einzugsgebieten analysiert. Statistische Analysen unter Berücksichtigung von Basisabfluss, Bodenvorfeuchte und verschiedenen Niederschlagscharakteristika wurden verwendet, um auf das Abflussvolumen zu schließen. Auf den verschiedenen Skalen konnte eine hohe Korrelation zwischen der mittleren Bodenfeuchte und dem Abflussbeiwert der Einzelereignisse festgestellt werden. Hierbei konnte die Bodenfeuchte genauso viel Variabilität erklären wie der Basisabfluss. Im Hinblick auf Zielsetzung 3 wurden “Generalised liner models” (GLM) genutzt. Dabei wurden Prädiktorvariablen die den Gebietszustand beschreiben und solche die die Meteorologische Randbedingungen beschreiben genutzt um den Abflussbeiwert zu schätzen. Die Ergebnisse der GLMs wurden mit Simulationsergebnissen des hydrologischen Gebietsmodells WaSiM ETH verglichen. Hierbei haben die GLMs eindeutig bessere Ergebnisse geliefert gegenüber den WaSiM Simulationen. Die GLM Analysen haben aufgezeigt, dass die verwendete Messstrategie mehrerer TDR-Cluster in typischen funktionalen Einheiten eine viel versprechende Methode ist, um den Einfluss der Bodenfeuchte auf die Abflussentwicklung zu verstehen und ein Bindeglied zwischen den Skalen darstellen zu können. Langzeitbeobachtungen solcher Standorte sind in der Lage wichtige Zusatzinformationen bei der Hochwasserwarnung und -vorhersage zu liefern durch die Identifizierung kritischer Gebietszustände für erstere und eine bessere Repräsentation der Vorfeuchte für letztere.

>Magister Scientiae - MSc / Catchment forums are concerned groups of people that come together on a voluntary basis in a specific area. They share the same goal and purpose to achieve - sustainable water resources management. These Catchment Forums are suppose to give a voice for those who are marginalised, by creating a safe space in smaller gathering of familiar people on water issues.Higher level organisations such as Department of Water Affairs and Forestry and Catchment Management Agencies have a responsibility to look after these forums. The main focus of this research is to develop an in-depth understanding of these catchment forums, elaborate on the role they play in water resources management, what impact or influence they have on governance in the catchment and the difficulties that they experience through the process of acting as custodian of water resources. Another crucial part of this research is to describe public participation approached by Department of Water Affairs and Forestry in the process of writing the proposal to establish a catchment management agency, determine the role of catchment forums in the establishment of catchment management agency in the Olifant-Doorn Water Management Area and the necessity of these forums as an organisational type in the establishment of catchment management agency. Minutes from the meetings of the Reference Group in the Olifants-Doorn Water Management were therefore the primary source of data. Additional data sources were approved proposals and field notes. Consultants who facilitated the public participation process were consulted from time to time to verify information.The National Water Policy hints at an ideal state where all residents of a catchment are in a position to negotiate water allocation and resolve resource-based conflicts in an equitable manner. One of the key themes evident in the Nation Water Policy of South Africa and echoed in the National Water Act and Water Service Act is participatory water management. For the public participation process in the Olifants-Doorn Water Management Area, catchment forums almost seemed unnecessary, since there were 38 other stakeholder groups active. This study has shown that catchment forums in the Olifants-Doorn Water Management Area participated at the level of collaborate. When it is taken into consideration that the higher level includes all the lower levels, catchment forums had sufficient opportunity to influence the decision taken in the process of writing the proposal to establish the Olifants-Doorn Catchment Management Agency, without experiencing the need or having the clout to actually make the decision.Key words: Catchment Forums, Catchment Management Agencies, decision-making,governance, iwrm, public participation.

M.Sc. (Geography) / One of the main objectives of the National Water Act (Act 36 of 1998) is the protection of natural resources (water resources) against pollution and misuse. These resources must be protected for the sustainable use by future and present generations. The study area consisted of the Kromdraai Catchment which included the Upper Wonderfonteinspruit, Lower Wonderfonteinspruit, Loopspruit and the Mooi River. This area is known for the amount of gold mining activities which may have a negative influence on the environment and especially on water. The aim of this study is to determine the impact of the gold mining industry may have on the water quality of the Kromdraai Catchment. Huge volumes of water quality data were collected from certain major monitoring stations throughout the Kromdraai catchment. A good indicator of pollution in a water sample is the electrical conductivity (Ee) of the sample. EC values were used to determine the pollution in each of the water samples because it saves time and costs. Pollution trends were established and conclusions were drawn to determine the impact of the gold mines on the water quality. A clear impact of a tailings dam on the water quality of the Turffontein Oog was established by the sharp increase in the EC values since the Doornfontein Gold Mine started depositing huge volumes of slime on the no. 3 tailing dam. The EC values of the Turffontein Oog have started to decline when the depositing of the slime was ceased. The conclusion of the study is that the gold mining industry has a definite negative impact on the water quality of the water resources in the Kromdraai catchment. The only effective way to mitigate and, manage these negative impacts, is through integrated environmental management. The sharing of data by all interested and affected parties is of critical importance, since most neighbouring goldmines are directly impacting on each other through the pumping and discharging of huge volumes of mine water. Catchment forums were established for the integrated environmental management of the Kromdraai catchment by all interested and affected parties. These forums have become important bodies representing stakeholders in the establishment of catchment management authority (CMA) that Will be established in the Upper Vaal Water Management Area.

An endmember mixing analysis (EMMA) is a hydrograph separation technique used to identify and quantify stream source contributions, but the error within the results of the analysis itself can be difficult to quantify. Employing EMMA to accurately quantify these contributions is particularly important for critical watersheds that supply water to large populations, such as montane watersheds. We applied EMMA to the Provo River, a nested catchment with three monitoring locations in northern Utah, to understand the limitations and potential improvements that could be made to EMMA. Four main endmembers (quartzite groundwater, soil water, snow and carbonate groundwater) were identified for the watershed and differentiated using the conservative tracers δ18O, δ2H, Si, HCO3-, Mg2+, K+, and Ca2+. In a traditional EMMA approach, a principal components analysis (PCA) is used to identify endmembers for a single location in a watershed, and the principal component (PC) scores are used to calculate the fractional contributions of each endmember. However, we found that calculating the fractional contributions of the endmembers in tracer space resulted in less error in the calculations compared to performing the calculation in PC defined space (U-space). Performing the mixing in tracer space with four endmembers showed that during spring runoff, snow was the main endmember with inputs ranging from 23 – 66% for the highest part of the watershed and 14 – 60% for the lowest part of the watershed. During baseflow, the stream was dominated by groundwater with contributions ranging from 23 – 60% quartzite groundwater for the upper part of the watershed and 30 – 57% carbonate groundwater for the lower part of the watershed. The amount of error present in the results depended on the scale of the catchment and the number of endmembers included, with more error in downstream locations relative to upstream locations. The nested catchment approach is a further improvement on traditional EMMA because it allows for identification of missing endmembers and error analysis for characterizing stream chemistry in several locations in a complex watershed.