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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.
1

Afforestation in South Australia, 1870-1950

Manhood, Cleve. January 1961 (has links) (PDF)
Thesis (B.A.(Hons.))--University of Adelaide, 1962. / [Typewritten].
2

An interdisciplinary approach to improving the design of contingent valuation studies to estimate the non-market value of complex environmental goods

Chilton, Susan Mary January 1996 (has links)
No description available.
3

Assessment and modelling of water chemistry in a large catchment, River Dee, NE Scotland

Wade, Andrew John January 1999 (has links)
This thesis describes the water chemistry of the River Dee and its tributaries, and the potential water chemistry changes that may occur under acid deposition and land use change scenarios. Historic water quality and flow records were collated and supplemented with new water chemistry data. These data were analysed in relation to catchment geography and river flow using both mathematical modelling and novel, GIS based techniques. This analysis established the importance of diffuse inputs and highlighted differences between upland and lowland regions in the catchment. In headwater streams, different geological types create hydrochemical source areas that strongly influence stream chemistry whilst in lowland tributaries, agricultural sources are particularly important. In the upland region most major ions were diluted as flows increased, further emphasizing the influence of deeper geological sources on baseflow chemistry, but showing soilwater controls on stormflow composition. The headwaters, which drain predominantly acid rocks, are presently oligotrophic but threatened by the impact of acid deposition and land use change (re-afforestation). In some of the lowland tributaries, increased NO3-N concentrations have resulted from more intensive land management. The potential impacts of acid deposition and land use change were simulated in both upland and lowland catchments by considering existing and new models within a Functional Unit Network. For upland regions this consisted of developing a new, two component hydrochemical mixing model to simulate the spatial and flow-related variations in streamwater acidity. The mixing model was based on End Member Mixing Analysis (EMMA), and site specific end members (alkalinity and Ca) could be predicted from emergent catchment characteristics (soil and land use) using linear regression.
4

Environmental impact assessment in the forest sector of Great Britain

Gray, Ian Munro January 2001 (has links)
Environmental impact assessment has been in use within the British forest sector since 1988 when the Environmental Assessment (Afforestation) Regulations became effective. In Great Britain between 1988 and 1998 a total of 211 applications for grant assistance for afforestation proposals have been subject to environmental impact assessment. Of these 101 had been completed by 1998 and the assessment concluded. This research details the development of environmental impact assessment in international, national and forest sector contexts, and presents a review procedure tailored for use in the British forest sector. Using this procedure, 89 forest sector environmental statements were reviewed. The review highlights the overall poor quality of environmental impact assessments and environmental statements within the British forest sector. The research investigates the efficacy of the Forestry Commission's screening process and its ability to identify projects with potential impacts through the development of a screening protocol for use in the British forest sector, which was used Forest Commission staff to screen a series of case studies. The survey, prediction and assessment techniques employed within forest sector environmental impact assessments are analysed. For a sample of assessments where adequate baseline information was included in the original assessment, a practical audit of impact predictions was carried out, where the actual outcomes of predicted impacts were compared with information derived from field investigation.
5

Reclamation of strip mine overburden through tree planting

Lowenberger, Frederick John January 1973 (has links)
Kaiser Resources Limited is extracting coal from a major strip mining operation near Sparwood, B.C. In spite of the recognized economic benefits which accrue from this mine, serious consideration must he given to its potential deleterious effects. Problem areas include accelerated erosion, water pollution, danger of slides and a barren landscape in and around the mine. A reclamation program has been initiated to minimize these problems. It includes land-use planning, physical alteration of topography, revegetation and subsequent tending of reclaimed land. This thesis is related to the revegetation aspect of the above program in that it investigates the feasibility of establishing and growing coniferous trees on overburden. Development of plantations on these mine wastes fits well into the overall reclamation plan as seventy percent of the area to be reclaimed is best suited to growing trees. In addition, trees provide a suitable long-term means of minimizing erosion and pollution. Field work carried out to provide necessary data included the establishment of spring and fall replications of ten sample plots on mined sites around Michel and Natal. One plot was also set out on a small inactive area at the high elevation mine site on Harmer Ridge. The plots were situated and designed so that the effects of site, elevation, species choice, type of planting and time of planting on survival and growth could be studied. Planting was carried out during September 1970 and May 1971. The final collection of data took place during May 1972. Results indicate that trees are suitable for use in the revegetation of the residuals of the Kaiser mine. Analysis reveals spring planting survival to be much higher than that obtained from fall planting. Trees grown in the organic soil plug prototype container show better survival and growth than do bare-root seedlings or stock grown in plastic bullets. The optimum age of planting stock appears to be two years. Trees were successfully established over a wide range of elevations. Of the three species planted, Douglas-fir, lodgepole pine and Engelmann spruce, lodgepole pine did best between elevations of 3500 to 5000 feet. Above 5000 feet Engelmann spruce gave superior results. High mortality occurred on compacted sites and south facing slopes. Successful reforestation of compacted areas will require some form of site preparation to take place prior to planting. Plants other than trees, such as shrubs and grasses, should be used to regenerate south slopes. Successful plantation establishment will be dependent upon the control of both erosion and accidental damage. Proper planning at the highest management level will be required to minimize accidental damage while a variety of site preparation techniques will have to be utilized to control erosion. Further studies of reclamation problems are still required to ensure successful long-term results. Future research possibilities are therefore suggested. / Forestry, Faculty of / Graduate
6

Forest plantation management strategies for economic development of Uganda

Moyini, Yakobo Z. G. January 1978 (has links)
The pace of economic development in Uganda has been slow. National output has not increased fast enough. There has been evidence of a long-term deterioration in the terms of trade, elements of export instability and a serious stress in the balance of payments. Employment and rural development have been less than satisfactory. A possible strategy for alleviating these problems involves a more rational utilization of natural resources, of which the forestry sector is one. A review of the past performance of the forestry sector indicated that its contribution to the Gross Domestic Product was minimal, 2.1%. Furthermore, employment in forest management was small and unstable and imports of forest products have increased faster than exports. On the other hand, forest industries were labour-intensive, ranking second to the textile industry and contributing 10% of the total employment in manufacturing. The lack of a sound forest policy and a quantifiable production goal was identified as a possible cause of the poor performance. Forestry was relegated to the position of a handmaid to agriculture and the size of the national forest estate was limited to a minimum of 8% of the total land area of the country. If the forestry sector is to contribute substantially to economic development, it must be well planned. To achieve this the identification of optimum product-oriented management models for forest lands is necessary. By the year 2000 A.D. maximum consumption requirements 3 in million M were estimated to be 46.85 for fuelwood and charcoal, 2.89 for poles and posts, 1.0 3 for sawnwood and sleepers and 0.15 for wood-based panels; and 0.25 million metric tons for paper and paperboard. Based on roundwood supply projections at current levels of management and timber prices, the forest resource of Uganda will be unable to meet the anticipated demand by the year 2000. Increased utilization of the lesser-known species in the tropical high forests is a feasible medium-term strategy for avoiding timber scarcity. In addition, preliminary studies indicate that species such as Cyanometra alexandrii (CH. Wright) offer real promise in the export sector and should, therefore, be processed. However, for a much more sustained production with attendant improvements in quality and yield per hectare, a greater effort towards forest plantations is advocated. Five product-oriented softwood (Pinus patula Schl. Cham and P. caribaea Morelet var. hondurensis) management models were forumulated and tested for efficiency. Two of the models had close spacing (2200 stems/ha) with a light (IA) and a heavy (IB) thinning. Model IC had intermediate spacing (1800 stems/ha) with two heavy thinnings; ID with wide spacing (900 stems/ha) and a heavy thinning; and IE, the current management regime, has a wide/intermediate spacing (1370 stems/ha) with three thinnings. The "VYTL" simulation model developed at the Commonwealth Forestry Institute (Oxford) was used to produce yield tables for the management models. The models appropriate for Eucalyptus grandis (Hill) Maiden had already been adequately analysed elsewhere. In terms of efficiency, model IC had the highest mean 3 annual increment (29.4 M³/ha/year at age 20) and ID attained a mean dbh of 20 cm earliest, at age 11. Using the Faustmann formula and assuming a constant timber price (models IA, IB and IC) and a size-responsive revenue function (models ID and IE), the optimum rotations in years were 17 for IA, 19 for IB, 22 for IC, 27 for ID and 29 for IE. Substantial economies in the use of land can be achieved by adopting the appropriate management strategies. Model IA was best suited for pulpwood production and IE for veneer and saw logs. For an integrated pulpwood/veneer and saw log production, model IA was most suited if greater emphasis was on pulpwood and IC if the emphasis was on veneer and saw logs. Based on the revenue assumptions for the determination of rotation length, model IE had the largest amount of present net worth (U.shs 3374/ha at 6% discount rate) and ID, the highest internal rate of return (10.50 percent). When either the amount of initial capital outlay, or total cost compounded to rotation age required to produce a unit volume of wood was used to measure cost-effectiveness, model IE was the most efficient. Taking into account all these efficiency rankings, model IE was selected as the optimum product-oriented management strategy for veneer and saw log production, IA for pulpwood and IC for an integrated pulpwood/veneer and saw log production. Having identified the optimum management strategies, their implications for economic development in terms of foreign exchange earnings, investment requirements, employment and rural development were assessed. The greatest opportunities for foreign exchange earnings were in import-and product-substitution. The economic values of substitution locally produced softwood sawnwood for prime grade hardwoods on the domestic market and for imports of softwood sawnwood were estimated to be U.shs 1400 and 727 per M³ respectively. Direct or seedling credit schemes for eucalypt woodlot farms were recommended and will require a maximum investment of U.shs 1461 million and employ 183 thousand persons per annum. For softwood plantations, a maximum investment of U.shs 213 million and employing 62,000 persons annually will be needed. Due to the existence of an artificial surplus of land, a two-pronged strategy of forest area expansion and intensive management was considered optimal for Uganda. It was estimated that through adoption of the optimum intensive management models, the size of the national forest estate should be increased from the current 8% to about 17% of the total land area of the country to avoid future timber scarcity. To lessen the disparities in the standard of living among regions, industrial plantations should be located in economically depressed areas. A land availability index, expressed as a function of regional rate of land utilization, carrying capacity, actual population density and real per capita income was used to determine potential sites for establishing plantations. Those districts with land availability indices below the national average were considered economically depressed. They were Madi, West Nile, Acholi (East and West), Lango, Mubende and Bunyoro, in a decreasing order of severity. The last four offer greatest promise for plantation forestry. Finally, the management strategies identified in this study should provide the main basis for sound social cost-benefit analyses of forestry projects. It is hoped the projects will subsequently be adopted in the next development plan of Uganda. / Forestry, Faculty of / Graduate
7

Soil and afforestation in the Shing Mun Country Park, Hong Kong

Yau, Fung-yee, Caroline. January 1997 (has links)
Thesis (M.Phil.)--University of Hong Kong, 1997. / Includes bibliographical references (leaf 238-249). Also available in print.
8

Soil and afforestation in the Shing Mun Country Park, Hong Kong /

Yau, Fung-yee, Caroline. January 1997 (has links)
Thesis (M. Phil.)--University of Hong Kong, 1997. / Includes bibliographical references (leaf 238-249).
9

Detritus retention and invertebrate communities in forestry impacted streams

Pretty, James L. January 2000 (has links)
No description available.
10

Perception of forest aesthetics in Québec, Canada

D'Amour, Therese January 1976 (has links)
No description available.

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