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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Geology, geomorphology, and dynamics of mass movement in parts of the Middle Santiam River drainage basin, western Cascades, Oregon /

Hicks, Bryan A. January 1982 (has links)
Thesis (M.S.)--Oregon State University, 1982. / Typescript (photocopy). Some maps folded in pocket. Includes bibliographical references (leaves 156-169). Also available via the World Wide Web.
12

Some bedded zeolites, San Simon basin, southeastern Arizona

Edson, Gary M. (Gary Morency), 1940- January 1977 (has links)
No description available.
13

Modelling the spatial characteristics of hydrometeorology in the Upper Oldman River Basin, Alberta

Sheppard, Dennis Leslie, University of Lethbridge. Faculty of Arts and Science January 1996 (has links)
A characteristic of alpine drainage basins is the very sparse distribution of meteorological recording stations. This study models a contiguous distribution of microclimate and snowpack accumulation in the upper Oldman River basin. To accomplish this goal, gaps between weather recording stations are first filled using a modified MTCLIM climate simulation model in conjunction with the spatial analysis capabilities of the PAMAP geographic information system (GIS). The GIS provides terrain information such as elevation, slope, and aspect on a 100 metre grid as input into the microclimate simulator which, in turn, outputs daily meteorological conditions for a user-defined period of time. The estimation of snowpack accumaltion is achieved with another component of the model which makes use of the modelled microclimate to calculate daily accumulation and ablation on a grid point basis. Simulation results are returned to the GIS for display and spatial analysis. Discussion includes such thngs as the grouping of terrain variables and the derivation of an altitudinal precipitation profile, both of which are required for computational efficiency. While regression analysis indicates a very close relationship between observed and simulated temperature, precipitation is less successfully modelled at the daily time scale. Comparisons of simulated temperature with observed data resulted in an r2 + .94 and are therefore considered very reliable. Daily precipitation comparisons initially indicated a low correlation between observed and simulated data. However, when monthly totals are considered instead, r2 rises to 0.66. When snopack conditions are simulated for several snow pillows in the region, regression analysis with observed data producers r2 values as high as 0.896. / xi, 178 leaves : ill., maps ; 29 cm.
14

Aquatic insects as an energetic subsidy to riparian consumers in the Olman River Basin, Alberta

Becker, Allison L January 2012 (has links)
Freshwater and terrestrial ecosystems are connected through biomass exchanges such as the flow of predators, prey, nutrients and detritus between them. Emerging aquatic insects provide an alternate food source to riparian consumers often termed an allochthonous subsidy. Stable isotope analyses of naturally occurring carbon and nitrogen is effective for tracing energetic food sources to consumers. This thesis evaluated whether stable isotope analysis would be effective in the Oldman River Basin, Alberta. Aquatic and riparian primary consumers are distinct in their isotopic signatures and valid for to use in stable isotope analysis. Stable isotope modelling was then used to evaluate the proportional contribution of aquatic insects to riparian spider and beetle diets. Carbon analysis showed an overall aquatic insect contribution of 25 % and 18 % for spiders and beetles, respectively; while nitrogen analysis showed an overall contribution of 36 % and 20 %, respectively. The spatial extent of the aquatic insect contribution upland from the river was shown to decrease from 50 - 55 % at 1 m to 0 % at 30 m for both consumers using carbon, and from 35 - 40 % at 1 m to 0 % at 40 m using nitrogen. Finally, regression modelling of the size of a river and the spatial scale of an aquatic insect dietary contribution showed a significant relationship, indicating larger water bodies support higher production of aquatic insects. A meta-analysis of published literature applied to this model also indicated a significant relationship between the size of the river and the extent of an aquatic insect contribution. / xii, 126 leaves m ; 29 cm
15

Quantifying baseflow inputs to the San Pedro River a geochemical approach /

Baillie, Matthew Nelson. January 2005 (has links) (PDF)
Thesis (M.S. - Hydrology and Water Resources) - University of Arizona. / Includes bibliographical references (leaves 70-74).
16

Climate variability and extremes in the Okavango River Basin, southern Africa

Moses, Oliver 11 September 2023 (has links) (PDF)
The Okavango River Basin (ORB) located in southern Africa is a region of highly sensitive and biodiverse ecosystems. It spans Angola, Namibia and Botswana, with the world-famous Okavango Delta located in the latter country. The ecosystems depend on the highly seasonal ORB streamflow, which is also the major source of freshwater for the rural population, most of whom depend on subsistence farming. Climate variability and extremes such as droughts, hot days and extreme rainfall events are not well understood over this region. Also, the relationship between climate and other aspects like vegetation and river discharge are not well understood. To contribute to a better understanding of this relationship, the thesis investigated relationships between rainfall, temperature, Normalized Difference Vegetation Index (NDVI) and river discharge, and their interannual variability and trends. It was found that at monthly and seasonal time scales, NDVI spatial patterns are closely related to those of rainfall than temperature. The NDVI-rainfall and NDVI-temperature relationships differ north of 18.9°S where rainfall is higher than to its south. Correlations between NDVI and rainfall show lags of 1-2-months. Large areas across the region show significant warming trends in all seasons but mainly in October-December (OND), as well as wetting mainly in the north. The warming trend may imply more evaporation and desiccation which may exacerbate extreme event impacts such as severe droughts. Interannual variability of rainfall, NDVI and temperature is pronounced with significant correlations with El Niño-Southern Oscillation (ENSO), the subtropical Indian Ocean Dipole (SIOD) and the Botswana High for rainfall and temperature, and for NDVI with ENSO. The temperature (rainfall) correlations with ENSO and the Botswana were positive (negative), with the SIOD they were negative (positive), and the NDVI-ENSO correlations were negative. On longer time scales, the wet 2006-2013 period was analysed relative to much drier 1999-2005 epoch for OND. The 2006-2013 wetter conditions appear linked to La Niña Modoki conditions, regional circulation differences and warmer sea surface temperature near Angola. Extreme rainfall events over the ORB were analysed. The analysis was performed within a larger region in western central southern Africa (WCSA), given that many rainfall events extend beyond river basin boundaries. Focus was placed on extreme rainfall events accumulated over 1-day (DP1) and 3-days (DP3), during the main rainy season, January-April (JFMA). Due to data sparsity, the Climate Hazards Group Infrared Precipitation with Station data (CHIRPS) were used to identify these events. It was found that contributions of DP1 and DP3 events to JFMA rainfall totals are, on average, ~10% and ~17%, respectively, but in some years their contributions exceed 30%. Most of the events result from tropical-extratropical cloud bands, with tropical lows being also important. Interannual variability in extreme events is substantial and appears linked to ENSO and the Botswana High. Although ENSO influences the extreme events and rainfall totals more generally over southern Africa, by far the neutral JFMA 2017 season experienced the wettest conditions over the world-famous Okavango Delta region. Factors that contributed to these heavy rains included a deeper Angola Low, weaker mid-level Botswana High and anomalous westerly moisture fluxes from the tropical southeast Atlantic during January – early March. The second most intense rainfall event occurred on April 22nd, resulting from a cut-off low. DP1 frequencies show significant increasing trends, and similarly, rain-days and rain totals over many areas. These trends have important implications for agricultural and water management as well as wildlife conservation in the ORB. To contribute to a better understanding of drought over the ORB region, the thesis analysed various drought metrics. These include a Cumulative Drought Intensity (CDI) index, based on the product of maximum dry spell duration and maximum temperature anomaly, and the Standardised Precipitation-Evapotranspiration Index (SPEI). Strong horizontal gradients in frequencies of dry spells and hot days were found to shift south over the ORB from August to November as the tropical rain-belt shifts increasingly south of the equator, the Congo Air Boundary declines and the Botswana High strengthens and shifts south-westwards. By December, the tropical gradient in dry spell frequencies is unnoticeable while that across the Limpopo River and southern ORB region, where the Botswana High is centred, stands out. On seasonal time scales, October-November 2013-2021 is particularly hot and dry over the Okavango Delta region. The thesis provided evidence that this hot and dry epoch is related to a stronger and southward shifted Botswana High and reduced low-level moisture convergence. On interannual time scales, there were strong relationships with the Botswana High, and to lesser extent ENSO. A strong drying-warming trend was found in the early summer, linked to a significant strengthening of the Botswana High. These trends, in conjunction with the Coupled Model Intercomparison Project Phase 6 (CMIP6) projected early summer drying over southern Africa found in the literature, may impact severely on the sensitive ecosystems of the ORB, and on water availability as well as subsistence farming in the region.
17

Nisqually conflict renewed

McCurdy, Jane L January 2010 (has links)
Photocopy of typescript. / Digitized by Kansas Correctional Industries
18

Islamic foundations for effective water management : four case studies

Walz, Jonathan David 16 February 2011 (has links)
This thesis project addresses Islamic water management by presenting case studies on regional water issues and analyzing the extent to which Muslim-majority states behave in a way consistent with Islamic shariah law. The case studies presented in this thesis address both international cooperation related to the management of trans-boundary water basins (the Nile and Tigris-Euphrates River Basins) and domestic water management strategies employed by Muslim-majority states in the MENA region (Jordan and Yemen). In each case, it is not clear that there is consistency between the Islamic ideals discussed by academics and the actual techniques employed by various states. In international attempts at managing the shared waters of the Nile and Tigris-Euphrates Basins, the fact that many riparian states have Muslim-majority populations does not appear to make the management of trans-boundary resources any easier or more successful. The implications for Islamic water management at the domestic level is also unclear – with shariah playing a positive role in Jordanian attempts at water conservation but promoting the over-exploitation of resources in Yemen. Although shariah appears to play a limited role in the management of trans-boundary water resources, it seems to be better suited for informing how states internally manage their endowments of freshwater resources. / text
19

Renewable energy outlook for the Drina River Basin countries

Fejzic, Emir January 2020 (has links)
The Drina River Basin (DRB) plays a vital role for the power sectors of the riparian countries of Bosnia and Herzegovina, Montenegro and Serbia. The Drina river and its tributaries have a considerable hydropower potential, which, due to its geographical position and the political landscape between the riparian countries, have not yet been utilized to its full potential. This study aims to investigate the role of hydropower and other renewables in the future energy mix under different scenarios. Additionally, the study aims to examine the renewable energy penetration within the DRB, as well as changes in total CO2eq emissions from the power sector by 2035. The study describes the implementation and testing of a modelling framework with the purpose of analysing the future energy mix. To answer the key research questions, an energy model was created using the Open Source Energy Modelling System (OSeMOSYS). Input parameters for the model were obtained through information gathering based on literature reviews, interviews with local experts and reviews of policy documents. The scenario analysis includes a business as usual scenario (BAU), a nationally determined contribution scenario (NDC), renewable energy scenario (RE) and a sensitivity analysis based on three different levels of implementation of the emission trading scheme (ETS). The results indicate that the share of hydropower differ amongst the scenarios, ranging between 41% and 55% by 2035. The scenario results also show that the share of RES located within the DRB ranges between 45-58% by 2035, in relation to the total installed RES capacity in the basin countries. This high share of economically feasible RES potential highlights the importance of the DRB, particularly since the basin area accounts for approximately 12,8% of the total country area. Furthermore, the obtained resultsfrom the scenario analysis indicate the possibility of emission reductions between 7% and 50 % by 2035, compared to the BAU scenario emissions. / Flodområdet Drina (DRB) spelar en central roll för kraftsektorerna i de angränsande länderna Bosnien och Hercegovina, Montenegro och Serbien. Drinafloden och dess bifloder har en betydande vattenkraftpotential som, på grund av dess geografiska position och komplexa politiska landskap, inte har utnyttjats till fullo. Denna studie syftar till att undersöka förnybara energikällors roll i den framtida energimixen, under olika scenarion, med fokus på vattenkraft. Studien ämnar fortsättningsvis att undersöka penetrationen av förnybar energi inom DRB, såväl som förändringar i de totala CO2-utsläppen från kraftsektorn, fram till år 2035. Vidare beskriver studien implementeringen och testningen av en modelleringsram framtagen med syftet att analysera den framtida energimixen. För att besvara forskningsfrågorna skapades en energimodell med hjälp av Open Source Energy Modelling System (OSeMOSYS). Inmatningsparametrar för modellen erhölls genom informationsinsamling baserad på litteraturgranskningar, intervjuer med lokala experter samt granskningar av nationella policydokument. Scenarioanalysen inkluderar ett Business as Usual scenario (BAU), ett Nationally Determined Contribution scenario (NDC), ett scenario för Renewable Energy (RE) samt en känslighetsanalys baserad på tre olika nivåer för implementering av systemet för utsläppshandel (ETS). Resultaten indikerar på att andelen vattenkraft skiljer sig mellan scenariona och sträcker sig mellan ett intervall på 41% och 55% år 2035. Scenarioresultaten påvisar även att andelen RES som ligger inom DRB varierar mellan 45–58% fram till 2035, i förhållande till den totala installerade RES-kapaciteten inom de angränsande länderna. Den höga andelen ekonomiskt genomförbar RES-potential belyser betydelsen av DRB-området, framför allt då flodområdet utgör cirka 12,8% av det totala landområdet. Vidare indikerar resultaten från scenarioanalysen möjligheten till utsläppsminskningar på mellan 7% och 50% fram till 2035, jämfört med utsläpp indikerade i BAU-scenariot.
20

Tools to assess the ecohydrological impacts of water system innovations

January 2009 (has links)
Water scarce countries such as South Africa are subject to various hydrological constraints, particularly within resource poor farming communities that are reliant on rainfed agriculture. Recent initiatives to address this issue have shifted focus to explore more efficient alternatives to water supply. Adoption of water system innovations through the use of runoff harvesting is one such alternative that provides a means to supplement water use for increased food production. However, increasing the implementation of runoff harvesting, without encountering unintended impacts on downstream hydrological and ecological systems, requires better understanding of the hydrologic and environmental impacts at catchment scale. The objective of this dissertation was to gain knowledge to the ecohydrological impacts that are likely to occur with the adoption of water system innovations as a means for upgrading rainfed smallholder farming systems. To fulfil this objective, a research component was developed whereby tools were utilised to facilitate this process on the basis of two broad aims. The first aim entailed developing a method for locating areas that are most suitable for the adoption of runoff harvesting using Geographical Information Systems (GIS). This was achieved by spatially modelling physical properties of the landscape which influence runoff response. Combining potential runoff with socio-economic factors produced a runoff harvesting map of sites with low, medium and high suitability. This is illustrated by a case study at the Potshini catchment, a small sub-catchment in the Thukela River basin, South Africa. The second aim involved modelling the impacts that runoff harvesting would have on the downstream hydrology and ecology based on the alteration of the flow regimes. To accomplish this, the ACRU Agrohydrological model which was configured to represent runoff harvesting, was used to simulate streamflow for quaternary catchments within the headwaters of the Thukela River basin. Simulated streamflows from ACRU was input into the IHA model to generate ecologically relevant hydrological parameters. Alteration of the flow regime due to runoff harvesting was mostly a reduction in high and low flows however the impacts were insignificant. This suggests that, depending on the intensity of runoff harvesting, downstream ecological impacts are insignificant. / Thesis (M.Sc.) - University of KwaZulu-Natal, Pietermaritzburg, 2009.

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