<p>The hydrological conditions on the southern slopes of Mt Kilimanjaro, Tanzania, are complex and not similar to very many other places. High annual precipitation with complex distribution patterns occurs on these slopes. Extensive water consumption and concentrated groundwater sources of unknown origin are found on the plains. The distribution and utilisation of the scarce water resources can easily be influenced by change in these and in other factors. A hydrological model is developed for the area and used for studying these processes and their influence on potential change in land use and climate.</p><p>This study is a part of a cooperative project between the University of Dar es Salaam, Tanzania and the Norwegian University of Science and Technology in Trondheim, Norway, focusing on how changes in land use influence the hydrologic -al responses of a catchment.</p><p>Extensive fieldwork has been performed in the course of several stays in the area. Three gauging stations were established on the slopes south of Mt Kilimanjaro for gauging the runoff from areas with and without influence from human activities. Precipitation and temperature measurements from the lower boundary of the forest reserve and up to 4000 metres above sea level (masl) were performed. Extensive field surveys were performed for identifying and understanding the hydrological processes taking place in the catchment. In addition, hydrological data were collected from the regular observation network.</p><p>The stream gauging and the precipitation measurements were analysed. The results were used in a water balance assessment of the southern slopes of Mt Kilimanjaro for determination of the extent of infiltration in the higher areas. Based on the results from the three sub-studies, a hydrological model was developed which describes the vertical water balance above and in the soil zone. The model can be used for investigation of the hydrological impact of changes in land use or climate. The model takes meteorological data as an input in addition to parameters describing the land cover and water demand in the catchment. This was applied for analysing the impact of prospective land use and climate changes.</p><p>The analysis of the discharge data and field inspections indicated that no surface runoff comes from the area above 2800 masl. The study of the precipitation data resulted in a function describing the relative distribution of precipitation according to elevation for the southern slopes of Mt Kilimanjaro. The analysis indicates that the maximum precipitation intensity occurs about 400-500 meters higher than previously assumed. The water balance assessment gave indications on the extent of the deep groundwater infiltration on the southern slopes of Mt Kilimanjaro. </p><p>These findings were incorporated into the hydrological model, which was calibrated for three catchments on the southern slopes of Mt Kilimanjaro. The calibration for a small 21 km² uphill catchment, a mid-hill 52 km² catchment and a large 1783 km²catchment reaching from the plains to the peak of Mt Kilimanjaro showed good accordance between the simulated and the observed discharge for the three catchments.</p><p>The calibrated model was successfully used for simulating the period from 1958 to 2000 for the large catchment and showed good accordance for the simulation period. Simulations with changes in forest cover, water demand and climate were performed. The climate changes simulated were based on the findings from the Intergovernmental Panel on Climate Change and land use and forest cover and were evaluated on the basis of potential management schemes. The simulations indicate that the water demand in the area is not being met, and that changes in water demand are not fully reflected in the river discharge. The results also show that the changes have greater influence in years where the water deficit is already substantial, so called “dry years”, than in years with a smaller deficit.</p><p>The tools developed and illustrated can be developed further for use in operational water management predicting the hydrological response due to changes in land use and water demand based on various management schemes. It is advised that the infrastructure developed during this work for collecting further measurements concerning the hydrological elements in the area continues to be operated.</p>

This thesis examines the hydrological characteristics of West Washmawapta Glacier, an overdeepened cirque glacier located in the Vermillion Range, B.C., Canada. Fieldwork involved drilling nine boreholes, which were surveyed with a borehole camera and instrumented with combinations of pressure transducers, thermistors and electrical conductivity sensors. Results show the cirque hydrology consisted of a predominantly subglacial, distributed drainage system. Hydraulic jacking occurred within the overdeepened region in both the summers of 2007 and 2008. Hydrological shut-down occurred very late, potentially due to the effect of the riegel on basal drainage, preventing flow out of the overdeepening at lower water pressures. Basal water temperatures were observed to fluctuate diurnally (up to 0.8^0C) above the local pressure melting point, likely due to influx of geothermally-heated groundwater and insulation of water within a sediment aquifer. Varying basal water pressures and temperatures suggest that hydraulic potential and supercooling effects are often over-simplified in glacier studies.

Thesis (M.S.)--Indiana University, 2007. / Title from screen (viewed on Apr. 27, 2007) Department of Earth Science, Indiana University-Purdue University Indianapolis (IUPUI) Includes vita. Includes bibliographical references.

The hydrological conditions on the southern slopes of Mt Kilimanjaro, Tanzania, are complex and not similar to very many other places. High annual precipitation with complex distribution patterns occurs on these slopes. Extensive water consumption and concentrated groundwater sources of unknown origin are found on the plains. The distribution and utilisation of the scarce water resources can easily be influenced by change in these and in other factors. A hydrological model is developed for the area and used for studying these processes and their influence on potential change in land use and climate. This study is a part of a cooperative project between the University of Dar es Salaam, Tanzania and the Norwegian University of Science and Technology in Trondheim, Norway, focusing on how changes in land use influence the hydrologic -al responses of a catchment. Extensive fieldwork has been performed in the course of several stays in the area. Three gauging stations were established on the slopes south of Mt Kilimanjaro for gauging the runoff from areas with and without influence from human activities. Precipitation and temperature measurements from the lower boundary of the forest reserve and up to 4000 metres above sea level (masl) were performed. Extensive field surveys were performed for identifying and understanding the hydrological processes taking place in the catchment. In addition, hydrological data were collected from the regular observation network. The stream gauging and the precipitation measurements were analysed. The results were used in a water balance assessment of the southern slopes of Mt Kilimanjaro for determination of the extent of infiltration in the higher areas. Based on the results from the three sub-studies, a hydrological model was developed which describes the vertical water balance above and in the soil zone. The model can be used for investigation of the hydrological impact of changes in land use or climate. The model takes meteorological data as an input in addition to parameters describing the land cover and water demand in the catchment. This was applied for analysing the impact of prospective land use and climate changes. The analysis of the discharge data and field inspections indicated that no surface runoff comes from the area above 2800 masl. The study of the precipitation data resulted in a function describing the relative distribution of precipitation according to elevation for the southern slopes of Mt Kilimanjaro. The analysis indicates that the maximum precipitation intensity occurs about 400-500 meters higher than previously assumed. The water balance assessment gave indications on the extent of the deep groundwater infiltration on the southern slopes of Mt Kilimanjaro. These findings were incorporated into the hydrological model, which was calibrated for three catchments on the southern slopes of Mt Kilimanjaro. The calibration for a small 21 km2 uphill catchment, a mid-hill 52 km2 catchment and a large 1783 km2 catchment reaching from the plains to the peak of Mt Kilimanjaro showed good accordance between the simulated and the observed discharge for the three catchments. The calibrated model was successfully used for simulating the period from 1958 to 2000 for the large catchment and showed good accordance for the simulation period. Simulations with changes in forest cover, water demand and climate were performed. The climate changes simulated were based on the findings from the Intergovernmental Panel on Climate Change and land use and forest cover and were evaluated on the basis of potential management schemes. The simulations indicate that the water demand in the area is not being met, and that changes in water demand are not fully reflected in the river discharge. The results also show that the changes have greater influence in years where the water deficit is already substantial, so called “dry years”, than in years with a smaller deficit. The tools developed and illustrated can be developed further for use in operational water management predicting the hydrological response due to changes in land use and water demand based on various management schemes. It is advised that the infrastructure developed during this work for collecting further measurements concerning the hydrological elements in the area continues to be operated.

Many active stream conduits within karst aquifers transport and deposit non-carbonate, clastic sediment. However, little is known about how these sediments impact conduit development and enlargement rates. For example, can dissolution take place at the sediment/bedrock interface beneath a flowing stream? If not, cavern enlargement might be dominated by flood conditions when the bare rock of the walls and ceiling are in contact with the dissolving fluids. An approach using limestone tablet weight loss experiments, along with water sampling and geochemical modeling, has been undertaken to understand the nature of fluid movement and chemistry with the sediment beneath an active flowing cave stream within the Kentucky's Mammoth Cave System. Fluid flow and carbonate chemistry were compared between the active stream and within the sediment at 15, 30, 60, and 90 cm below the stream bed. It was found that carbon dioxide pressure within the interstitial fluids was elevated an order of magnitude above that of the stream waters, having levels as much as 31 times that of atmospheric background, presumably from microbial decomposition of organic material. The fluids were all under-saturated with respect to calcite (SI= -0.4 to -0.9), and limestone blocks buried at these levels all dissolved (rates from 0.8 to 21.9 g m -2 yr -1). These results suggest that at some locations the limestone bedrock may be dissolving beneath clastic sediment deposits; which in turn has implications for understanding rates and geometries of conduit evolution within karst aquifers.

Forest fires have an enormous impact on biotic and abiotic variables that control runoff and soil properties in watersheds. Because wildfires do not have a uniform effect on the burned area, significant variability occurs between areas of different burn severity and likely elicits different hydrologic responses within watersheds. Much of the control on this hydrologic response stems from the variability of soil between burned and unburned watersheds. Establishing a linkage between soil infiltration and burn severity may therefore, offer insight into the likelihood of elevated levels of runoff and the likelihood of floods. Although previous studies have sought to establish a quantitative relationship between runoff and burn severity, this relation has not been evaluated with respect to soil moisture and infiltration and varying degrees of burn severity. The Loretta-Linda Basin presents a unique opportunity to compare areas with different burn severities (with the right fork of the drainage experiencing a much higher burn severity than the left), while eliminating most other variables that may occur with greater spatial variability such as elevation, temperature, precipitation, underlying geology, and soil type. Rainfall, soil moisture, runoff, and infiltration data collected over a two-month period were used to evaluate the relationship between burn severity, runoff, and infiltration for the Loretta-Linda basin as a whole as well as for the individual forks of the basin. The impact of varying burn severity on the two sub drainages was further investigated by creating a dynamic simulation model in TopoFlow®. Comparative analysis between the two forks did not show a dramatic difference in the runoff and infiltration relationship between the two burn severities. Variability of field conditions, the presence of parameters affecting runoff not accounted for, and the limitations of point measurements, are reflected by the data analysis and lack of a strong correlation between burn severity, infiltration, and runoff. The use of spatial hydrologic modeling allowed for the investigation of the relative importance of the infiltration parameters as well as the impact of Manning’s n on the response of the basin to rainfall. The modeling results indicate a strong correlation between high burn severity, low infiltration capacity, and elevated discharge volumes.

This research examined equine management practices that limit or contribute to the spread of West Nile virus and other mosquito-bome disease. I hypothesize that there is a relationship between equine management practices and outbreaks of mosquito-borne disease in horse populations. Improved and appropriate mosquito habitat management may limit the risk of mosquito-borne disease in humans and horses by helping to lower the mosquito populations. The study goals were to recognize equine management practices and mosquito prevention practices that foster outbreaks of mosquito-borne disease. This study used a questionnaire for county level analysis of equine management practices and the relationship to mosquito-borne disease. This study is important because horses live in a natural setting among unmanaged elements, such as pastures with ponds, wooded areas, and riparian areas. However, horses themselves are highly managed. Equine management practices include pasture horses, who live exclusively outdoors, stabled horses who receive some turn-out time, and ultra-managed horses, such as race horses. Kentucky's economy is partially dependant on the horse industry, which is responsible for over 51,000 jobs and is a major part of the culture of Kentucky. Equine diseases can significantly affect this section of the state's economy. The study area consisted of three categories of noncontiguous counties, with each group containing three to four Kentucky counties. The three selected categories of study highlighted areas of West Nile virus incidence in equine populations. Surveys were distributed to horse owners and barn managers to collect data on differences in equine management practices and outbreaks of mosquito-borne disease. Two categories represented counties with large equine populations, and one category represented counties with low equine populations. Category I consists of the three counties that were selected based on high horse populations and high incidence of West Nile virus in 2002—Barren, Fleming, and Nelson counties. Category II consists of four counties with high equine populations and low incidence of West Nile virus in 2002 - Allen, Grant, Jessamine, and Meade counties. The third category looks at low equine populations and high incidence of West Nile virus in 2002 - Carlisle, Marion, Russell, and Todd counties. Areas with low equine populations and low incidence of West Nile virus were not considered for the study because those areas do not have either high horse populations or high incidence of West Nile virus and hence were not relevant for this particular research question about equine management practices. A minimum of thirty surveys was collected for each category. Statistical analysis was used to determine relationships between incidences of disease, management practices, and knowledge of mosquito prevention. Each survey question was analyzed using the two-tailed version of the two-sample difference of proportion test. West Nile virus is an important disease to study due to the potential economic loss to the horse industry but also because the disease has been responsible for sickness and death in human and animal populations. I studied horses because of the their mix of unmanaged and managed habitat. This study did find a difference in equine management practices when it came to vaccination to prevent West Nile virus occurrences in horse populations. Horse people in categories with high horse populations had a higher use of a West Nile virus vaccine to prevent disease than people use in the low horse population category. While statistics from this study show that there is little or no difference in other equine management practices between the three categories, this research demonstrates that few horse owners and barn mangers limit mosquito habitat around their animals or are aware of IPM techniques. Vaccination lowers the chance that a horse will develop West Nile virus, but it is important that active equine management programs include limiting mosquito habitat to assist in prevention of mosquito-borne disease. Limiting mosquito-borne disease is an important preventive strategy that could protect the health of both horses and humans.

The development of Geographic Information System (GIS) technology has provided techniques for a holistic approach to the study of karst groundwater contamination. While karst groundwaters supply water to a large percentage of the earth's population, its complex environments often have lacked the scientific examination and conservation measures typical of non-karst regions. In this study, GIS methodologies were explored to examine the relationships between land-use and water quality in karst watersheds. Eight watersheds throughout southern and western Kentucky were examined. The study areas included the Mammoth Cave Karst Aquifer, which is the watershed that drains the Mammoth Cave System, and seven watersheds that serve as sources of drinking water. Most of these watersheds exhibit karst geology and, therefore, are highly sensitive to groundwater contamination. Using GIS and remote sensing interpretation, land-uses within these watersheds were classified manually and coded according to the USGS Anderson system (Anderson et al., 1976). The majority of land-uses classified within these basins were agricultural. With the results of land-use analysis, statistical methods were employed in the development of a multivariate, predictive regression model to relate land-uses and contaminants thafhave agricultural land-uses as common sources (fecal coliform, nitrate, phosphorus, alachlor, atrazine, and simazine). Although the regression models resulted in relatively low r2 values (ranging from 0.076 to 0.169), future revisions of the models may increase these values. Potential revisions to the statistical models could include examining other statistical methods and exploring additional independent variables. Using the capabilities of GIS, including buffer analyses, database queries, and digital elevation analyses, areas of potential water quality degradation were located within the study watersheds. Land areas identified through GIS analyses can indicate target areas for implementation of Best Management Practices, information campaigns, incentive programs, and outreach by resource managers, scientists, or agricultural extension offices. High-risk land-uses, including feedlots and row crops, were found to be located in or near locations that may be key to karst groundwater quality (sinkholes, swallets, streams that sink into the subsurface). Such GIS analysis can provide tools to protect ecosystems and be a step toward providing a clean and sustainable drinking water source for Kentucky residents.

Climate Change Effects and Water Vulnerability in the Molalla Pudding River Basin, Oregon, USA

This thesis proposes a model for the interaction between ground flow and surface flow using a coupled system of the Navier-Stokes and Darcy equations. The coupling of surface flow with porous media flow has important applications in science and engineering. This work is motivated by applications to geo-sciences. This work couples the two flows using interface conditions that incorporate the continuity of the normal component, the balance of forces and the Beaver-Joseph-Saffman Law. The balance of forces condition can be written with or without inertial forces from the free fluid region. This thesis provides both theoretical and numerical analysis of the effect of the inertial forces on the model. Flow in porous media is often simulated over large domains in which the actual permeability is heterogeneous with discontinuities across the domain. The discontinuous Galerkin method is well suited to handle this problem. On the other hand, the continuous finite element is adequate for the free flow problems considered in this work. As a result this thesis proposes coupling the continuous finite element method in the free flow region with the discontinuous Galerkin method in the porous medium. Existence and uniqueness results of a weak solution and numerical scheme are proved. This work also provides derivations of optimal a priori error estimates for the numerical scheme. A two-grid approach to solving the coupled problem is analyzed. This method will decouple the problem naturally into two problems, one in the free flow domain and other in the porous medium. In applications for this model, it is often the case that the areas of interest (faults, kinks) in the porous medium are small compared to the rest of the domain. In view of this fact, the rest of the thesis is dedicated to a coupling of the Discontinuous Galerkin method in the problem areas with a cheaper method on the rest of the domain. The finite volume method will be coupled with the Discontinuous Galerkin method on parts of the domain on which the permeability field varies gradually to decrease the problem sizes and thus make the scheme more efficient.