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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.
251

FOREST HARVEST EQUIPMENT MOVEMENT AND SEDIMENT DELIVERY TO STREAMS

Bowker, Daniel Whiteside 01 January 2013 (has links)
Streamside management zones (SMZs) have become important management techniques to prevent the introduction of sediment to stream networks. This study examined the current Kentucky best management practice (BMP) guidelines for SMZs by outfitting mobile forest harvest equipment with global positioning system (GPS) receivers, enabling modeling of equipment traffic and spatial analysis of stream sediment delivery. Three SMZ configurations were implemented during commercial timber harvest, along with four different techniques of crossing ephemeral channels, in order to determine where and why sediment was introduced to the stream network. Results indicate that increasing the SMZ buffer width leads to decreased sediment delivery, and that requiring an SMZ buffer with some canopy retention on ephemeral channels will lead to improvements in stream water quality. Care should be taken in the placement and construction of water control measures for skid trail retirement, and improved stream channel crossings such as bridges and pipe culverts should be required to improve water quality over unimproved fords. A northeasterly aspect of harvested areas was shown to be related to increased sediment delivery to streams, while surface roughness downslope from the skid trail system was shown to decrease sediment delivery.
252

A practical assessment of spatial development frameworks in terms of water resources for development / by Hanneke Pretorius.

Pretorius, Hanneke January 2012 (has links)
There is no single resource so essential to sustaining life and livelihoods than water (UNDP, 2005). Water is furthermore a strategic resource that not only gives life, but is also a catalyst for development; therefore water has to and must be at the centre of all development plans (Buyelwa, 2009). Water can be the limiting factor for economic growth, upliftment and social development due to its scarcity and uneven distribution. Strategic spatial interface and relationship with water resource planning and management is fundamental to development and realisation of spatial potential. Strategic spatial planning has many components of which the Spatial Development Framework forms the key regulation to guide development and inform investment opportunities. The goal of this study is to determine the degree to which water resource management and planning is incorporated in Spatial Development Frameworks in context of strategic spatial planning. Concurrently international strategic spatial planning procedures and water resource management principles are investigated to correlate the local situation with international trends. A Goal Achievement Matrix (GAM) with ten assessment principles is developed as a tool for evaluation of strategic spatial planning and water resource management documents in terms of the local municipal level. This GAM may be used and implemented as a comparative evaluation tool to compare the degree of integration and implementation of water resource management and strategic spatial planning of local municipal authorities internationally. The percentage score as achieved in evaluation of the GAM indicates the degree of integration of water resource management and planning with strategic spatial planning. The cumulative result of the GAM scored 68% which can be used as a degree of comparison in future studies with other local municipalities, even on an international level. Measured in terms of the different authority levels the local level performed the worst with a 50% GAM score whilst the national level has a high GAM score of 86%. The low local level score indicates that exceptional legislation and policies on national level are not sufficient to eradicate poverty, provide water for all and provide for long-term sustainability if the implementation at local level falters. The low local level score may also be attributed to a lack of institutional capacity and lack of appropriate skills. It is concluded that Spatial Development Frameworks (as a component of strategic spatial planning) and water resource management and planning on a local level are not effectively integrated and it is recommended that water resources and planned future development must be effectively managed and integrated in order to ensure sustainable communities at local level. As a planning recommendation, the Guidelines for the Development of Spatial Development Frameworks developed by the Department of Rural Development and Land Reform must be extended to incorporate the integrative approach between strategic spatial planning and water resource management as a fundamental aspect. The effective integration of water resource management and planning in strategic spatial planning is key to sustainable, equitable and viable communities. / Thesis (MArt et Scien (Urban and Regional Planning))--North-West University, Potchefstroom Campus, 2013.
253

A practical assessment of spatial development frameworks in terms of water resources for development / by Hanneke Pretorius.

Pretorius, Hanneke January 2012 (has links)
There is no single resource so essential to sustaining life and livelihoods than water (UNDP, 2005). Water is furthermore a strategic resource that not only gives life, but is also a catalyst for development; therefore water has to and must be at the centre of all development plans (Buyelwa, 2009). Water can be the limiting factor for economic growth, upliftment and social development due to its scarcity and uneven distribution. Strategic spatial interface and relationship with water resource planning and management is fundamental to development and realisation of spatial potential. Strategic spatial planning has many components of which the Spatial Development Framework forms the key regulation to guide development and inform investment opportunities. The goal of this study is to determine the degree to which water resource management and planning is incorporated in Spatial Development Frameworks in context of strategic spatial planning. Concurrently international strategic spatial planning procedures and water resource management principles are investigated to correlate the local situation with international trends. A Goal Achievement Matrix (GAM) with ten assessment principles is developed as a tool for evaluation of strategic spatial planning and water resource management documents in terms of the local municipal level. This GAM may be used and implemented as a comparative evaluation tool to compare the degree of integration and implementation of water resource management and strategic spatial planning of local municipal authorities internationally. The percentage score as achieved in evaluation of the GAM indicates the degree of integration of water resource management and planning with strategic spatial planning. The cumulative result of the GAM scored 68% which can be used as a degree of comparison in future studies with other local municipalities, even on an international level. Measured in terms of the different authority levels the local level performed the worst with a 50% GAM score whilst the national level has a high GAM score of 86%. The low local level score indicates that exceptional legislation and policies on national level are not sufficient to eradicate poverty, provide water for all and provide for long-term sustainability if the implementation at local level falters. The low local level score may also be attributed to a lack of institutional capacity and lack of appropriate skills. It is concluded that Spatial Development Frameworks (as a component of strategic spatial planning) and water resource management and planning on a local level are not effectively integrated and it is recommended that water resources and planned future development must be effectively managed and integrated in order to ensure sustainable communities at local level. As a planning recommendation, the Guidelines for the Development of Spatial Development Frameworks developed by the Department of Rural Development and Land Reform must be extended to incorporate the integrative approach between strategic spatial planning and water resource management as a fundamental aspect. The effective integration of water resource management and planning in strategic spatial planning is key to sustainable, equitable and viable communities. / Thesis (MArt et Scien (Urban and Regional Planning))--North-West University, Potchefstroom Campus, 2013.
254

The Effect of Climate Change on Food Security in Sub-Saharan Africa

Long, Shelby K 01 January 2015 (has links)
The purpose of this thesis is to examine the projected future changes in the global and Sub-Saharan Africa climate. These changes are expected to have varying effects depending on the region of the globe being examined. Sub-Saharan Africa is expected to be one of the most vulnerable regions in the future because of the already-variable and unpredictable climate. Population growth and lack of financial and informational resources further exacerbates the climate problems, making it even more difficult for African farmers to respond to their changing environment. In order to respond to these climate changes within an already dry and nutrient-lacking environment, farmers must be given the necessary adaptation information and aid from outside investors. However, without the proper information available to investors, regarding future expectations about precipitation, temperature, extreme weather events, soil nutrients, and available adaptation strategies, investors cannot efficiently allocate capital or other forms of aid. Therefore, I stress the importance of developing accurate climate models on a regional scale that investors can use to better allocate aid. Each region is affected in very different ways by the climate as a result of local topographical factors and global factors, such as the Intertropical Convergence Zone. Therefore, tools, such as models and simulations must be able to take these factors into account in order to accurately project future changes. This thesis examines a wide range of existing literature in the area of climate change and food security on both a global and regional scale. I investigate the current and future climate of Sub-Saharan Africa, as well as the farming culture, in order to provide an in-depth understanding of the various factors that are interacting. Although many steps have been made to develop models and provide aid to Sub-Saharan Africa farmers, the lack of food security is only expected to become worse as the environment becomes harsher on food crops. Therefore, in order to respond to the expanding population and harsher farming environment, farming adaptations must continue to be intensified.
255

Capital, Accumulation, and Crisis: Surveying the Neoliberal Waterscape of Municipal Privatization in Canada

Lang, Michael Keith 26 August 2013 (has links)
While the outright privatization of water services has declined globally, it has been replaced with public-private partnerships (P3s) in the government procurement and delivery of water services, and increasingly at the local level. This research finds that such initiatives are on the rise in Canada, and considering the overall record of failure that has amounted from varied types of water privatization thus far, it seeks to analyze this expanding waterscape from a critical perspective. More specifically, by historically situating the privatization of Canadian municipal water in a political-economic context that identifies its relation to contemporary (neoliberal) capitalism, this research examines how the focused state commitment to water P3s is indicative of the processes of neoliberalization. I argue that regulatory and budgetary changes since the economic crisis of 2008 have formed an institutionalized policy apparatus that essentially forces needy municipalities into long-term contracts with private firms, therefore establishing sustained sites for capital accumulation. This thesis concludes with a discussion concerning the implications that such a “partnership” will have for municipal autonomy, organized labour, and the environment, particularly in light of the intensifying state focus on international free trade. / Graduate / 0626 / 0629
256

The development and application of a charge-coupled device based instrument for at-site monitoring of algae and cyanobacteria in freshwaters

Carswell, Leo David Cecil January 2002 (has links)
The research presented in this thesis describes the development and application of a portable, high-resolution instrument, specifically designed for the at-site monitoring of algae and cyanobacteria in freshwaters. The instrument incorporates a miniature charge-coupled device (CCD) based spectrometer and a low power combined deutelium and tungsten light source, enabling the absorbance to be measured between 200 - 850 nm at a resolution of 1.3 nm. A transmission dip probe with removable tips of 5, 10 and 40 mm pathlengths forms the sampling device. A specifically developed control program allows easy operation of the instrument. A linear response from 0.0 - 1.2 AU and a combined signal to noise ratio of 576: 1 for the instrument components resulting in a high baseline stability of 1.0 mAU drift over five hundred measurements being observed. The instrument provides in-vivo absorbance characteristics with high resolution across the visible spectrum. Up to twelve specific spectral features were commonly identified in the absorbance spectra of algae and cyanobacteria between 400 - 750 nm. Individual spectral features were linked to specific pigments, some of which were found to be taxonomically distinct. Fourth derivative analysis was proven to provide further enhancement of subtle spectral features. The instrument has a linear range for chlorophyll a up to 1000 !lg rl and a detection limit of 8 )lg rl using the 40 mm pathlength probe. Physiological adaptation to light and nutrient conditions were shown to have a significant effect on the in-vivo absorbance spectrum, therefore providing potential information on physiological status and health of a natural sample. Spectral analysis using principal component analysis (PCA) with classification based on the soft independent modelling of class analogy (SIMCA) method was used to classify nine species from three taxonomic classes, including four cyanobacteria (Microcystis aeruginosa, Anabaena variabilis, Aphanizornenon flos-aquae, Synechnococcus sp.), four chlorophyceae (Chlorella vulgaris, Scenedesmus acuminatus, Spirogyra mirabilis, Staurastrurn chaetoceros) and a single bacillariophyceae (Asterionella Formosa). Classification using the SIMCA method proved to be highly reliable and robust. Moreover, the addition of noise was found to have very little effect on the classification. Under laboratory conditions all nine species were correctly classified using 'unknown' spectra. At-site classification of natural samples and laboratory simulations have shown the robustness and reliability of the developed portable instrument. In combination with the data analysis techniques, the instrument is well suited to the proactive at-site assessment of algal and cyanobacterial blooms in eutrophic freshwater environments.
257

Ensuring Our Future or Sowing the Seeds of Our Own Destruction? Crop Insurance and Water Use in Texas

Shapiro, Michael 01 January 2015 (has links)
Agriculture is the largest consumer of water in the United States. Policies that affect agriculture therefore have the potential to have a large effect on the overall use of water. Crop insurance is one such policy, which was found to significantly increase water use in the state of Texas. Much, but not all of this effect can be explained by an increase in planting density, and results vary widely by crop and by region.
258

Human-river relationships in the Kat River catchment and the implications for integrated water resource management (IWRM) : an exploraratory study /

Birkholz, Sharon Alice January 2009 (has links)
Thesis (M.Sc. (Geography)) - Rhodes University, 2009.
259

An assessment of the companion modelling approach in a context of negotiating water allocation strategies : the case of the Kat River Valley, Eastern Cape, South Africa /

Gumede, Felicity Hlengiwe January 2008 (has links)
Thesis (M.Sc. (Geography)) - Rhodes University, 2008
260

Denitrification and Greenhouse Gas Dynamics in Lakes Receiving Atmospheric Nitrogen Deposition

January 2010 (has links)
abstract: The global transport and deposition of anthropogenic nitrogen (N) to downwind ecosystems are significant and continue to increase. Indeed, atmospheric deposition can be a significant source of N to many watersheds, including those in remote, unpopulated areas. Bacterial denitrification in lake sediments may ameliorate the effects of N loading by converting nitrate (NO3-) to N2 gas. Denitrification also produces nitrous oxide (N2O), a potent greenhouse gas. The ecological effects of atmospheric N inputs in terrestrial ecosystems and the pelagic zone of lakes have been well documented; however, similar research in lake sediments is lacking. This project investigates the effects N of deposition on denitrification and N2O production in lakes. Atmospheric N inputs might alter the availability of NO3- and other key resources to denitrifiers. Such altered resources could influence denitrification, N2O production, and the abundance of denitrifying bacteria in sediments. The research contrasts these responses in lakes at the ends of gradients of N deposition in Colorado and Norway. Rates of denitrification and N2O production were elevated in the sediments of lakes subject to anthropogenic N inputs. There was no evidence, however, that N deposition has altered sediment resources or the abundance of denitrifiers. Further investigation into the dynamics of nitric oxide, N2O, and N2 during denitrification found no difference between deposition regions. Regardless of atmospheric N inputs, sediments from lakes in both Norway and Colorado possess considerable capacity to remove NO3- by denitrification. Catchment-specific properties may influence the denitrifying community more strongly than the rate of atmospheric N loading. In this regard, sediments appear to be insulated from the effects of N deposition compared to the water column. Lastly, surface water N2O concentrations were greater in high-deposition lakes compared to low-deposition lakes. To understand the potential magnitude of deposition-induced N2O production, the greenhouse gas inventory methodology of Intergovernmental Panel on Climate Change was applied to available datasets. Estimated emissions from lakes are 7-371 Gg N y-1, suggesting that lakes could be an important source of N2O. / Dissertation/Thesis / Ph.D. Biology 2010

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