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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.
111

An economic analysis of Wisconsin's diversion permit system for agricultural irrigation

Osterhoudt, Frank Howard, January 1968 (has links)
Thesis (M.S.)--University of Wisconsin--Madison, 1968. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
112

Harbour reclamation in Hong Kong land production and landuse planning : the environmental perspective /

Cheung, Wai-hung, Tony, January 1997 (has links)
Thesis (M.U.D.)--University of Hong Kong, 1998. / Includes bibliographical references (leaves 63-65) Also available in print.
113

Long-term ecosystem development on an open-cut coal mine in central Queensland /

Kopittke, Gillian Ruth. January 2005 (has links) (PDF)
Thesis (M.Phil.) - University of Queensland, 2006. / Includes bibliography.
114

Classification of subwatershed slopes and geotechnical characterization of steep slopes on reclaimed mine lands in East Tennessee

White, Patrick Hamilton. January 2009 (has links) (PDF)
Thesis (M.S.)--University of Tennessee, Knoxville, 2009. / Title from title page screen (viewed on Nov. 6, 2009). Thesis advisor: Eric Drumm. Vita. Includes bibliographical references.
115

Habitat Associations of Grassland and Shrubland Bird Communities at Reclaimed Surface-Mines in Southern Illinois

Duncan, Shawn 01 May 2011 (has links)
The grassland bird-community has declined significantly in abundance and diversity in Illinois over the past century. Reclamation of surface coal-mines in southern Illinois has created ca. 50,000 ha of grassland habitat that offers surrogate habitat for grassland and shrubland birds. Much of the grassland habitat created by reclamation of mine lands has not been managed and has succeeded to shrubland habitat dominated by both native and non-native shrubs. The purposes of this research were to identify the bird community utilizing reclaimed surface-mines in southern Illinois, and to examine the habitat-associations of the bird community and compare those to previously reported habitat-associations. I examined bird communities, plant structure and composition, and invertebrate communities at grasslands and shrublands at 3 reclaimed surface-mines in southern Illinois. I used 100-m wide strip-transects to survey the bird community and measured habitat characteristics including: vegetation height and density, litter depth and cover, shrub density and height, and plant composition. I observed 57 bird species over 126 surveys in 2008 and 2009. I used Generalized Linear Models and Akaike's Information Criteria to develop habitat-association models for 7 bird species: Henslow's sparrow (Ammodramus henslowii), grasshopper sparrow (Ammodramus savannarum), eastern meadowlark (Sturnella magna), dickcissel (Spiza americana), indigo bunting (Passerina cyanea), field sparrow (Spizella pusilla), and Bell's vireo (Vireo belli). Of these 7 species, dependable models were found for the Henslow's sparrow, grasshopper sparrow, eastern meadowlark, and field sparrow. The best habitat model for Henslow's sparrows indicated a positive association with % litter cover and a negative association with large variations in grass cover. The best habitat model for grasshopper sparrows indicated a negative association with both litter cover and depth and a positive association with grassland area. The best habitat model for the eastern meadowlark indicated a negative association with visual obstruction and shrub density. The best habitat model for the field sparrow indicated a curvilinear association with shrub density and visual obstruction. The habitat-association model for Henslow's sparrows differed from previous research in that neither vegetation height nor density were indicated as important habitat characteristics. To identify the habitat characteristics that have the greatest effect on the overall bird-community composition, I generated graphical ordinations using non-metric multidimensional scaling. The habitat factors most affecting the bird community composition were: vegetation density, vegetation height, litter depth, shrub density, shrub height, warm-season grass cover, and the ratio of habitat area to perimeter. Invertebrate biomass at a site was positively correlated to forb cover and plant richness and negatively correlated to grass cover. Grassland bird species have distinct habitat-associations that allow them to reduce interspecific competition through niche partitioning and would be best managed with a diverse set of successional stages.
116

From marshes to reclamation : there and back again : contested nature, memories and practices in two wetlands of Agro Pontino, Italy

Gruppuso, Paolo January 2016 (has links)
What is a wetland? What does this category imply? Is it different from a land which is wet? This thesis addresses these questions through a study of environmental conflicts in two protected wetlands in Agro Pontino, Italy. This region, 70 kilometres south of Rome, was affected between the 1920s and the 1930s, by one of the most important operations of land reclamation of that time, conducted by the fascist regime which drained the largest marshland in Italy, i.e. the Pontine Marshes. Based on fieldwork in protected wetlands considered as the remnants of the Pontine Marshes, the thesis includes the analysis of various original case studies, such as the activities of Environmental Interpretation and farming, among others. Moreover, it discloses archive records that cast new light on the social and environmental context of the Pontine Marshes. The thesis explores how farmers and conservationists relate with a particular kind of environment, namely wetlands in conservation areas; their relations with non-humans; their different reading of the history and evolution of these landscapes and the connections between these aspects and the conflicts affecting these areas. These conflicts concern different ideas of what a wetland should be and the appropriate practices aimed at implementing those ideas. The research, which is influenced by the work of Tim Ingold, challenges the established notion of wetland, based on a topographic and spatial understanding of the world, suggesting that wetlands are patterns characterized by movements, tasks and activities: entanglements of innumerable life-lines traced by human and non-human beings in the accomplishment of their tasks. It is in this entanglement which politics emerge, conflicts flourish and life goes on. Accordingly, I argue that following these life-lines and exploring what I call the geography of the meshwork, can disclose new interpretative perspectives to understand environmental conflicts.
117

Geo-hydrological remediation of hydrocarbon contaminated soil at Johannesburg International Airport

Raleru, Sylvia 05 February 2009 (has links)
M.Sc.
118

Community based soil conservation as basis for land reclamation in the Eastern Cape

Maswana, Ntombokuqala Nokulunga 10 November 2005 (has links)
Soil erosion is a hazard that is adversely affecting agricultural production in the Eastern Cape province. The climatic conditions ad parent material (natural resources) are not conducive for the development of stable soil. This situation is, however, aggravated by amongst other things, poor planning, bad agricultural practices, land tenure, population pressures, overgrazing, etc. Soil reclamation has become one of the Government’s priorities. However, all their attempts have failed. On the other hand the interventions by NGO’s have been successful. This study has found that the most effective way to address the soil reclamation problems and ensure that the soil conservation initiatives are successful and sustainable, is to: 1. Involve the natural resource users (the local community). Community involvement entails the following: -- The community taking ownership and the lead in the initiative -- Where there is a need they must be empowered to make informed decisions. -- For the participation to be effective, there must be technology transfer. -- The immediate beneficiaries must be the active participants. 2. Prevent soil degradation through development of sustainable farming systems for the poor soils. This is a process that needs detailed study of the natural resources as a first step. In this study it was learnt that poor planning as a result of lack of understanding or knowledge of the natural resource of the province, particularly the soil, is one of the key causes of soil erosion. A detailed study of the soils or soil survey of the Eastern Cape has become critically important in order to ensure that planning is based on facts rather than assumptions. This will pave the way for the development of sustainable farming systems. However, without addressing the land tenure system in the Eastern Cape province (communal), by giving ownership of land to the people it becomes difficult to ensure that farmers will invest in the land through soil reclamation and soil conservation practices. / Dissertation (M Inst Agrar (Land-use planning))--University of Pretoria, 2006. / Plant Production and Soil Science / unrestricted
119

Alternatives for development of unreclaimed land in the kootenay river floodplain, creston, British Columbia : a benefit-cost analysis

Bowden, Gary K. January 1971 (has links)
This thesis is an investigation of the economic potential for use of 15,000 acres of land in the Kootenay River floodplain at Creston, British Columbia. The Kootenay River flows north into Canada through this floodplain and enters Kootenay Lake 20 miles north of the International Border. The total area of the floodplain between Kootenay Lake and the Border is approximately 36,000 acres, of which 20,000 acres have been reclaimed for agriculture. This study is concerned with 15,000 acres which remain undeveloped, 10,000 acres being provincial Crown land, and 5,000 being Indian Reserve. At present this land is inundated annually by the freshet of the Kootenay River. It provides an important link in the habitat requirements of migratory waterfowl, is used lightly by hunters and fishermen, and provides limited grazing for beef cattle before and after the freshet. The impending completion of Libby Dam, upstream on the Kootenay River at Libby, Montana, will reduce the extent of annual flooding and the costs associated with more intensive use of the land. Consequently, there is considerable interest in intensive development of this land, either for agriculture as with the rest of the floodplain, or as a wildlife management area for the production of wildlife and use in outdoor recreation. Resource managers face the problem of determining which of these alternatives represents the optimum land use. This is a difficult problem, and its solution requires that the benefits and costs associated with each alternative be reduced to a common basis for comparison. This study attempts to make such comparisons on a rigorous basis through the use of benefit-cost analysis. The feasibility of each land use alternative is assessed, and comparisons made on the basis of the net present worth of benefits minus costs. The principles of benefit-cost analysis are well developed, and its application is not difficult when project costs and benefits are adequately reflected in factor prices. Difficulties are encountered in the present study, however, where the output from development for wildlife and outdoor recreation is not marketed and there are no prices to reflect the values created. In analysing the wildlife-recreation alternative, values are imputed to the recreational opportunities using recently developed concepts in evaluating non-priced resource uses. While values are established for direct recreational use, other important aspects of the output under this development are not valued (the production of wildlife independent of recreational use, the preservation of rare species, the fulfillment of international obligations regarding migratory birds). The analysis of this alternative is thus restricted to a comparison between the full costs and only those benefits which are expressed in monetary terms. A further important issue is that the relevant measure of benefits and costs may differ, depending on the 'referent group' from whose point of view the analysis is conducted. To demonstrate the importance of this matter the analysis in this study is conducted from the point of view of three referent groups, the local Creston economy, the province of British Columbia, and Canada as a whole. The outcome of a benefit-cost analysis may also be sensitive to the discount rate adopted, and the sensitivity is tested in this study using rates of six, eight and 10 per cent. Despite the difficulties of expressing all costs and benefits in monetary terms, a rigorous analysis is undertaken and provides the basis for a clear choice of the optimum form of land use. Analysis of agricultural reclamation reveals it to be feasible, with net present values of primary and secondary benefits ranging from $2.4 million from the local perspective to $2.2 million from the provincial and national points of view. Offset against these tangible net benefits are the intangible costs associated with the destruction of existing wildlife habitat and wildlife species. Analysis of the wildlife-recreation development produces widely varying results, depending on the referent group adopted. The net present value of primary and secondary benefits is estimated at $2.1 million from the local viewpoint, $4.6 million provincially, and $7.3 million from the point of view of Canada as a whole. In addition to these quantified values, this development will produce important unmeasurable benefits. In comparing the two, the net benefits estimated for agricultural development can be interpreted as maximum values, ignoring as they do some of the costs associated with wildlife losses. The net benefits estimated from the wildlife-recreation development are regarded as minimum values, since important additional values associated with wildlife production are not quantified.. Viewed in this light the choice between alternatives favors the wildlife-recreation development from both provincial and national perspectives, but is less clear at the local level. Since a basic premise of the study is that the provincial viewpoint is appropriate for decision making, it is concluded that the wildlife-recreation development represents the optimum land use. / Arts, Faculty of / Vancouver School of Economics / Graduate
120

The role of grass-legume communities in revegetation of a subalpine mine site in British Columbia

Yamanaka, Koji January 1982 (has links)
This study describes an investigation of the potential for pioneer grass-legume communities to stabilize and ameliorate geologically-fresh soil leading to the establishment of a self-sustaining, progressive plant succession on a surface-mined subalpine site. The study area is located 2,000 m above sea level in the Canadian Rocky Mountains. Field surveys at the site indicated extremely limited invasion of reclaimed areas (3-7 years old) by native species from the adjacent subalpine forest. Soils on revegetated sites were generally warmer and drier than soils of the associated forest and have less than half the content of fine soil fragments (<2 mm). Field studies revealed chronological trends in grass-legume communities at four sites revegetated during 1974-1978 including: species composition, legumes (Trifolium repens L., T. hybridum L. and Medicago sativa L.) performing increasingly poorly on the older sites; biomass changes, a shoot to root ratio (S/R) decreasing from 2.3 to 0.2 as the communities aged; and litter accumulation which continued even on the oldest site. Fertilizer (13-16-10) operationally applied at 150 -391 kg/ha enhanced the growth of Dactylis glomerata L. and litter degradation, and acidified the soil. Nitrogen fertilization was also associated with two clear inverse relationships identified between D. glomerata and Festuca rubra L. biomass, and between soil pH and phosphorus levels. In greenhouse tests grasses were revealed to be more efficient soil nitrogen consumers than were legumes and nitrogen fixation decreased significantly (P<0.01) and linearly with increasing grass seeding rates. In the presence of grasses, nitrogen fixation was positively correlated with aboveground legume biomass at all nitrogen fertilizer levels tested. The results further revealed that operational seeding and fertilizer rates at this site may not optimize plant productivity and the ability of legumes to fix nitrogen symbiotically. Field trials based upon the experimentaly derived combination (17.5 : 30 : 50 kg/ha grass seeding rate : legume seeding rate : nitrogen fertilizer rate) would be desirable to evaluate these data on the site. Other potential practical implications from this study are: (1) The need for improved legume establishment, involving legume seed germination, species and variety selection, and selection of Rhizobium strains. (2) Improved control of the operational fertilizer application. (3) Alteration of grass and legume species composition of the present seed mix. (4) Selective placement of initial material (overburden or spoil) handling. A modification of the acetylene reduction assay, "the open system" technique, was developed for evaluation of legume nitrogen fixation of mine spoils. Although the unit developed is limited to detection of the presence or absence of ethylene, calibration with the closed system of ethylene levels obtained by the open system appeared feasible. Further refinement of the system for quantitative use would increase its usefulness in nitrogen fixation studies of legumes on mine spoils, nitrogen fixing woody plants in forests, and legumes in grassland sods. / Land and Food Systems, Faculty of / Graduate

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