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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.
421

In the forest, field and studio : art/making/methodology and the more-than-written in the rendering of place

Thomson, Amanda Repo Taiwo January 2013 (has links)
This is an interdisciplinary arts practice based PhD that incorporates fieldwork into its exploration of Abernethy Forest in Cairngorms National Park, and Culbin Forest in Morayshire, Scotland. The thesis explores how a contemporary arts practice can articulate a place’s multi-layered complexities and how processes of coming to know influence and impact on the kinds of artworks created. This way of working incorporates an innovative approach that draws on geographical, anthropological, historical and ecological sources, and includes the synthesis of a contemporary arts practice with an ethnographic element - more specifically participant observation, with foresters, ecologists and others - as a mode of gathering. Description and examination of encounters in the field give context to the artwork and provide additional knowledge that lends insight into management practices and the knowledge that these workers possess. The research constitutes an original contribution to investigations of the forests of Culbin and Abernethy and correspondingly innovative outputs. This research proposes that a contemporary arts practice can articulate and communicate aspects and elements of place in ways that offer insights to artists, geographers, anthropologists and others. Central to this is the idea that places are multi-layered, everchanging, embodied, active and containing complex ecological, sensorial and physical histories and presences. Communicating these understandings requires a multi-faceted way of working and multi-modal ways of articulation in recognition of place as an experiential field of investigation. The art produced forms a non-linear, multi-stranded body of work that emphasises the benefits of multiple formats within an arts practice. The thesis enhances and further complicates conceptualisations of place that in geography and anthropology are often restricted to academic writing and demonstrates how artists and others can usefully enlarge and expand the ways in which places can be articulated and rendered.
422

AN INSTITUTIONAL AND ECONOMIC ANALYSIS OF THE ARIZONA TIMBER INDUSTRY

Moses, Thomas Clifford January 1981 (has links)
The purpose of this study was to investigate the pricing behavior between the Forest Service, the seller of national forest timber, and the firms in the Arizona timber industry, and buyers of this timber. The period of investigation was for the 1974 timber sales and the ultimate purchases of these sales through 1979. The market structure for the sale of national forest timber is one of monopoly on the part of the Forest Service and that of oligopsony for the industry. Two factors beside the market structure affect the behavior of the market participants. One, the interaction of the participants is constrained by several legal and institutional factors. Two, excess capacity exists in the industry and the supply of timber in Arizona is relatively fixed. Three methods were used in the study to analyze the behavior of the participants. First, the appraised value of the timber was compared to the residual value that could be afforded by each mill, using individual mill costs. Second, a linear transportation model was employed to determine the optimal allocation for the 1974 timber sales. The optimal results were then compared to the actual disposal for further analysis of the pricing behavior. Third, estimated profits were determined for the actual purchases of the 1974 sales and the results compared to the estimated profit allowances in the original appraisal. The results of the analysis showed the following. (1) The appraised values for the 1974 timber sales appeared to be overvalued. (2) The actual allocation of the 1974 sales was essentially optimal. The exceptions to the optimal allocations were generally where legal constraints prevented it. (3) Active bidding for the timber was minimal. Bidding among the firms included in the study occurred on slightly over 2% of the volume of the sales. The major conclusions reached from the analysis were that certain adjustments should be made in the appraisal process. These adjustments should be made for the lag effects of costs, the accuracy of imputed costs used, and the concept of profit allowance used. Also, the industry must improve its efficiency, especially in the area of utilizing the waste material from lumber production. The industry should also reduce its capacity to have a better balance between supply and demand, as supply is relatively fixed. Additionally, the behavior of the participants was determined to be as expected in view of the constraints, fixed supply, and locational factors. It is recommended that long-run study of this nature be conducted to offer more conclusive results.
423

Effects of Gambel oak on the characteristics of litter in a ponderosa pine forest

Lefevre, Robert Edward, 1950- January 1974 (has links)
No description available.
424

Resources and the regional economy: an historical assessment of the forest industry in British Columbia

Metcalf, Cherie Maureen 05 1900 (has links)
This thesis provides empirical evidence to assess the long term contribution of the B.C. forest industry to the provincial economy. Estimates of resource rent are constructed to measure the direct contribution of the resource to provincial income and growth. Measures of rent are constructed for a firm level sample (1906-76) and at an industry level (1918-92). The figures for rent are used to generate estimates of the share of provincial income measures directly attributable to the industrial exploitation of the province's forests. While there were periods during which the direct contribution to provincial income and its growth was nontrivial, in general the growth of forest industry rent did not drive overall economic growth but rather lagged behind. Rent was low on average and volatile during the years before W.W.II, rose rapidly from roughly 1940-51, then declined unevenly. To investigate the forces which underlie both the broad trends and the variability in rent, a stylized model of the forest industry is applied in an empirical analysis. Broad changes in aggregate rent were the result of changes in rent per unit of B.C. timber. The rapid increase in rent coincided with a marked rise in the price of forest products. The secular decline resulted from the combination of a falling output price and rising costs. An investigation of real harvesting costs indicates that depletion played a role in this increase. The variability of rent is also explored and found to be most strongly influenced by factors reflecting market risk which the B.C. industry could not diversity away from. The rent measures may not capture the full impact of the forest industry, so the industry's potential role as a leading export sector is also examined. The possibility of a stable long term link between forest exports and provincial income is investigated using cointegration tests. B.C. forest exports and G.D.P. are not cointegrated; their levels axe not linked in a deterministic way in the long run. A bivariate VAR, is used to examine the short run interaction between the growth of forest exports and provincial G.D.P. The results do not strongly support the view that the forest industry acts as a leading export sector in the provincial economy.
425

Identity, culture, and the forest: the Sto:lo

O'Neill, Amy 05 1900 (has links)
I offer some tentative thoughts on Sto:lo relations with the forest and, in turn, suggest how those relations may inform Sto:lo views on identity and culture. While highlighting the variety and complexity of Sto:lo attitudes toward the forest, I pay particular attention to those that appear contradictory. In so doing, I suggest that such "contradictions" are instead necessary antagonisms that spring from the constantly changing pressures to which the Sto:lo have been subjected, as well as from the ways in which they have struggled to cope with such pressures. More specifically, in pointing to Sto:lo attitudes towards forest work and forest conservation, I suggest that the Sto:lo have been forced and even encouraged to make claims to their identity that do not, and need not, conform with what is considered "traditional." In this way, my discussion is structured around the relationship between a sense of Sto:lo identity and the notion of cultural continuity, while aimed at highlighting the material as well as the intellectual realities behind that relationship. In a broader context, my discussion is aimed at reinforcing the need for more flexible examinations of Native identity; those that will highlight what it means to live in a modern Native culture, and what it means to be vulnerable to power.
426

Unlocking the code to hardwood pulpwood supply : an analysis to determine if intervention in the stump-to-mill supply chain by NCT will increase hardwood pulpwood supply from its members in KwaZulu-Natal?

Schütte, Craig Ernst. January 2006 (has links)
NCT Forestry Co-operative Limited has experienced decreased yearly hardwood pulpwood volume sales over the last several years. This indirectly means NCT members have decreased their hardwood pulpwood volume trade to NCT over the last several years. Combined with the general under-supply of hardwood pulpwood from its members, NCT's current systems do not accurately predict the monthly and yearly volumes from its members. This is because many factors play a role and influence the physical volume of hardwood pulpwood supplied during the marketing process from the stump to the mill. Two independent studies have been carried out by NCT, to determine the main factors causing NCT members to under-supply their hardwood pulpwood. Both reports sighted "price" as the major factor and driver in contributing to NCT members making a decision to bank their timber or dispose of it elsewhere. Due to NCT's core business being export orientated, "price" is considered to be "exogenous" by nature or defined as an "uncontrollable variable" as the mill delivered price NCT offers its members is a factor of the macro economic conditions between South Africa, United States of America and Japan. More specifically the "price" NCT offers its members is a factor of the exchange rate between the South African rand and the United States dollar. The second contributing factor which was sighted by NCT members as to why they were under-supplying their hardwood pulpwood was "operational issues". "Operational issues" can be refined to issues pertaining to the stump-to-mill supply chain. "Operational issues" as apposed to "price" can be considered as a "controllable variable" as every component within the stump-to-mill supply chain can be controlled and managed. This paper specifically undertakes to investigate, in more detail, what specific factors within the stump-to-mill supply chain are causing NCT members to under-supply their hardwood pulpwood to NCT. Mitigating research into the stump-to-mill supply chain as an area of concern for NCT is the fact that South Africa is currently and forecasted for the future, to have an under-supply and over-demand of hardwood pulpwood. This factor alone has many knock-on effects within the entire forestry value chain. Combined with the under-supply and over-demand situation for hardwood pulpwood, is the fact that NCT's competitors define the profile of an NCT member, being mainly associated to the medium and small grower category, as the most liquid form of hardwood pulpwood resource available. By understanding the problems the contracting fraternity faces in the value chain, further mitigates the focus on the stump-to-mill supply chain as a problem area for NCT. Research exposes that mainly "second economy" or "informal contractors" work in the environment of medium and small grower categories. For independent contractors, this environment is characterized by failure to reach economies of scale, lack of business skills, poor access to finance and training, difficulties in getting public liability insurance cover and limited help from the large corporate grower organisations. In general, NCT members falling into the medium and small grower categories will invariably experience un-professional service from independent contractors. This causes conflict in the stump-to-mill supply chain and can damage the marketing service NCT provides to its members and markets. The loyalty of NCT hardwood pulpwood owning members will be tested as the sale of hardwood pulpwood moves more and more into a "sellers" market, which will inherently mean an increase in the bargaining power and leverage these members will enjoy. Buyers who position themselves to satisfy these anticipated increased needs of private/independent growers will most likely enjoy competitive advantage. This study has found that competitive advantage partly lies in more control and management of the stump-to-mill supply chain. The study has also recommended that NCT adopt a combined strategy of backward vertical integration with keiretsu (a combined supply chain management strategy that incorporates few suppliers and backward vertical integration in a coalition partnership) in its approach to gain more control of the stump-to-mill supply chain. The study further concluded that the orthodoxy of supply chain management (SCM) emphasises competitive advantage through increased operational control and efficiency combined with market responsiveness from production and distribution processes into the hands of NCT. Further, the paper found that anticipated future competition for NCT would be between the stump-to-mill supply chains rather than between firms. Indirectly this means NCT will have to increase the scope of service to its members and that means increasing its service in the stumpto-mill supply chain. An effective hardwood pulpwood procurement (marketing) strategy rolled out by NCT using a combination of backward vertical integration and keiretsu as supply chain management strategies, in a drive to gain more control and management over the stump-to-mill supply chain was strongly recommended. This strategy will not only increase the control over the volume supplied to NCT but will also increase the sustainability of fibre by creating planned felling schedules. This strategy will also provide a stable environment for the "informal" or "second economy" contractors to work in, while satisfying the increasing needs of NCT members, and in the process creating a competitive advantage by providing a much-needed additional service. By adopting the supply chain management approach of using both backward vertical integration and keiretsu as strategies will allow for benchmarking between the two strategies to take place, while at the same time due to increased planning, economies of scale will be achieved leading to cost savings. Cost savings in the stump-to-mill supply chain will allow NCT more flexibility in defending its mill delivered prices. Hence, the key to unlocking the code to hardwood pulpwood supply from the NCT membership partly lies in the intervention of the stump-to-mill supply chain by adopting a dual supply chain management strategy of both backward vertical integration and keiretsu by NCT in the stump-to-mill supply chain. However, one can capture the hill by using "service" only, but this strategy will not necessary help you hold the hill. A combined strategy of "price" and "increased service" will more than likely allow NCT to capture and hold the hill. / Thesis (M.B.A.) - University of KwaZulu-Natal, Pietermaritzburg, 2006.
427

A systematic approach for using lidar intensity to detect forest structure.

Langford, Jaden Orion 12 November 2008 (has links)
Lidar intensity, a quantity analogous to backscatter, has yet to be fully exploited as an information source in the characterization of coniferous forests. Intensity images appear noisy due to (1) dynamic survey geometry, and (2) complex laser interactions in a forested environment. The nature of these issues are explored, and a systematic procedure for processing, visualizing, and normalizing the intensity data is presented. Despite high variability among neighbouring intensity values, the data are inherently spatially structured. Results from an investigation into the spatial pattern of intensity demonstrate that (1) the scale and variability of global estimates of spatial autocorrelation derived from raw intensity (point) data were markedly different between stands of different age, and these differences were driven by the canopy and gap structure within each individual stand, and (2) the magnitude of local estimates of spatial autocorrelation varied with canopy height, and, particularly in old growth stands, these magnitudes are linked to compositional factors such as species.
428

Effect of sewage sludge and clearfelling on the nutrient cycling of a mature Scots pine (Pinus sylvestris L.) stand

Mitchell, Diane January 1996 (has links)
The effects of sewage sludge application and the additional effects of clearfelling on nutrient cycling have been assessed in a mature Scots pine stand, north-east Scotland. The forest site was situated in a low rainfall area with high evapotranspiration and low leaching losses. The ground vegetation formed an important sink for N and P following sludge addition and clearfelling. Sludge application caused a foliar N response, increased foliar needle weight, and litterfall showed a significant and rapid potential to immobilize NH<sub>4</sub>-N and PO<sub>4</sub>-P added in sludge. The soil availability of NH<sub>4</sub>-N and PO<sub>4</sub>-P together with rates of mineralization of N and P and nitrification in sludge-treated areas were significantly increased compared with that of the control. Concentrations of NH<sub>4</sub>-N, NO<sub>3</sub>-N, PO<sub>4</sub>-P and organic P were increased significantly following sludge addition and fluxes were an order of magnitude greater than that of the control. Peaks in concentrations of NH<sub>3</sub>-N in sludge-treated areas exceeded the EC limit of 11.3 mg 1<sup>-1</sup> on several occasions. Of the total N and P applied to the sludge, throughfall and litterfall over a 17 month period, 2.4 % and 0.72 % were measured in the B<sub>s</sub> soil horizon flux. After clearfelling, initial increases in soil availability of NH<sub>4</sub>-N, NO<sub>3</sub>-N andPO<sub>4</sub>-P were measured. Felling increased nitrification rates, although increases were significant only in areas previously treated with sludge. Fluxes of NO<sub>3</sub>-N, NH<sub>4</sub>-N and PO<sub>4</sub>-P and organic P were increased at least an order of magnitude greater in felled areas than those of the control. Immobilization of N and P was greater in green and abscised litters placed in previously sludge-treated areas than compared with those placed in control areas.
429

Aspects of the ecology of black grouse (Tetrao tetrix) in plantation forests in Scotland

Haysom, Susan L. January 2001 (has links)
Aspects of the ecology of black grouse (Tetrao Tetrix), a species of international conservation concern, in commercial plantation forests were investigated between 1996 - 1998 at three study areas in Scotland. The aim was to identify the species' habitat and area requirements in first and second rotation forestry. The distribution of males was assessed using lek surveys and studied at two spatial scales in the mixed rotation forest landscape of Cowal, Argyll and at two spatial and temporal scales in highland Perthshire - a less afforested region. In addition, a radio-tracking study was undertaken to examine the habitat selection of broods in two first rotation plantations in north Perthshire. Pre-thicket forestry formed a preferred habitat but, in terms of lek distribution, black grouse did not differentiate between first and second rotation pre-thicket habitat patches. Patch size, the total amount of forestry in the area, the proportion that was pre-thicket stock and its level of fragmentation, however, were all correlated with the probability of a location holding a lek and the number of males attending it. Lek isolation reduced the number of males in attendance and increased the likelihood of the lek declining over time. Brood habitat preferences differed from those of adult birds. Broods selected habitats that were 'open' enough to support a rich ground flora and presumably an adequate invertebrate fauna but also 'closed' enough to provide cover, representing a compromise between foraging potential and predation risk. Brood roost sites differed by having shorter trees but a higher degree of cover 1-1.5 metres above the ground. Results from the different study areas and age classes are compared and contrasted and the implications of the research findings for 'black grouse friendly' forestry management are discussed. Finally, suggestions for further work are made.
430

The potential of airborne polarimetric synthetic aperture radar data for quantifying and mapping the biomass and structural diversity of woodlands in semi-arid Australia.

Cronin, Natasha Louise Rafaelle, School of Biological, Earth & Environmental Sciences, UNSW January 2004 (has links)
Levels of carbon dioxide in the atmosphere have been steadily increasing since the beginning of the Industrial Revolution in the 1800s. The earth's climate is sensitive to alterations in these levels of carbon dioxide and other greenhouse gases (GHG), with significant changes in climate predicted long term. The adoption of the Kyoto Protocol in 1997 heralded a new age in terms of greenhouse gas accounting and emissions responsibility, for all nations. In Australia, carbon emissions from the Land Use and Land Use Change and Forestry sector are responsible for a large proportion of the national total emissions. Radar remote sensing has demonstrated considerable potential in the estimation and mapping of vegetation biomass and subsequently carbon. The aim of this research is to investigate the potential of airborne polarimetric radar for quantifying and mapping the biomass and structural diversity of woodlands in semi-arid Australia. Initial investigation focussed on the physical structure of the woodland, which revealed that despite a diversity of woodland associations, the species diversity was relatively low. Both excurrent and decurrent growth forms were present, which subsequently resulted in varying allocation of biomass to the components (i.e., branches, trunks). In view of this, both empirical and modelling methodologies were explored. Empirical relationships were established between SAR backscatter and the total above ground biomass. Considerable scatter was present in these relationships, which was attributed to the large range of species and their associated structures. Comparison of actual and model simulations for C-, L- and P-band wavelengths, reveal that no significant difference existed for these wavelengths, except at CHH, and the cross-polarised data at L- and P-band. The study confirmed that microwaves at C-band interacted largely with the leaves and small branches, with scattering at VV polarization dominating. Compared to the lower frequencies, the return from the ground surface (as expected) was significant. The differences in scattering mechanisms (i.e., branch-ground versus trunk-ground) between excurrent and decurrent structures were due largely to the larger angular branches associated with Eucalyptus and Angophora species, which were absent from Callitris glaucophylla.

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