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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.
141

Trees and indigenous ecological knowledge about agroforestry practices in the rangelands of Shinyanga Region, Tanzania

Kilahama, Felician Bakamaza January 1994 (has links)
No description available.
142

Project appraisal under risk, threat and uncertainty : a case study of the afforestation project of Bihar, India

Shukla, Devendra Kumar January 1996 (has links)
In view of the Indian Government's growing commitment to forestry, a number of afforestation projects have been implemented. But most projects in developing countries do not conclude as per plan, uncertainty being a major factor. This study undertakes physical, financial, economic and social appraisal of the afforestation programme through case studies of the farm forestry (FF) and the rehabilitation of degraded forest (RDF) components and discusses the conceptual and methodological issues in appraisal of these projects under risk, threat and uncertainty. We have used three different approaches to risk appraisals in the present study. They are: the expected value of NPV through the illicit felling models; the cumulative distribution function comparisons through stochastic efficiency rules; the utility function of the project managers. Physical (logistic and Weibull models), financial and management decision (deterministic and probabilistic models) models developed in the study help in threat appraisal through quantification of physical loss, financial appraisal of its consequences and formulation of a management strategy under the threat of illicit felling. The risk analysis of the FF and the RDF component using Monte Carlo simulation is used to generate probability of return profiles and the results are compared through stochastic efficiency rules. The utility functions of the project managers are used to describe their risk attitude. The study shows that most managers are risk averse and the analysis of their utility functions supports the decreasing absolute risk aversion hypothesis. It emphasizes the need for a risk policy in the Forest Department. The economic appraisal examines the interaction of the FF and the RDF components with the economy rather than the treasury. Illicit felling is accounted for as a benefit to the economy. A 'Shadow pricing approach' is adopted for economic and social appraisals. For the social appraisal, inputs and outputs are estimated in terms of net discounted utility-weighted consumption flows. All the parameters of social and economic appraisal such as the consumption value of unit reinvestment, utility weight for incremental consumption at different consumption levels, social discount rate and economic discount rate are estimated. To study farmers' adoption behaviour, principal component analysis is used to explore significant factors and a logit model is developed after that to estimate probability of adoption. The study indicates that adoption of FF can be explained in an overall framework of evolutionary theory proposed in this study. The evolutionary theory posits that farmer tree growing can be considered as a land use strategy in response to both changing macro and micro factors, many of which relate to characteristics of the farmers, their resource endowments etc. It is concluded that success of projects can be assessed by taking account of the factors influencing the variability in the project outcome and understanding the whole process of people's interaction and participation in the project.
143

A knowledge-based systems approach to agroforestry research and extension

Walker, Daniel Harmen January 1994 (has links)
Agroforestry development programmes frequently rely on knowledge from a number of different sources. In particular, there is a growing recognition amongst development professionals of the value of augmenting partial scientific and professional understanding with the detailed knowledge held by local people. Taking advantage of the complementarity of local, scientific and professional knowledge demands the development of effective mechanisms for accessing, recording and evaluating knowledge on specified topics from each of these sources. The research described in this thesis developed a methodology for the acquisition, synthesis and storage of knowledge. The defining feature of the approach is the explicit representation of knowledge. This is achieved through the application of knowledge-based systems techniques. AKT2 (Agroforestry Knowledge Toolkit), a software toolkit developed in Prolog, an artificial intelligence programming language, provides the user with an environment for the creation, storage and exploration of large knowledge bases containing knowledge on a specified topic from a range of sources. The use of diagramming techniques, familiar to ecologists and resource managers through systems analysis, provides an intuitive and robust interface. This knowledge-based system drives incremental knowledge acquisition based on an iterative evaluation of the knowledge bases created. The iterative approach to knowledge acquisition provides a coherent, consistent and comprehensive, and therefore more useful, record of knowledge. Once created, knowledge bases can be maintained and updated as a record of current knowledge. Techniques for the exploration and evaluation of the knowledge base may be useful in : " giving research and extension staff access to a concise and flexible record of the current state of knowledge; " providing a resource and mechanisms for use in planning and prioritising research objectives; and " providing a resource and mechanisms for the generation of extension materials tailored to the needs of particular clients.
144

Ex-post cost-benefit analysis of village woodlots of Gujarat, India

Khan, Jamal Ahmad January 1993 (has links)
No description available.
145

The prediction of growth and wood quality parameters for plantation grown Pinus radiata D. Don. in New Zealand

James, R. N. January 1983 (has links)
Most of the wood harvested in New Zealand comes from plantations of the exotic species Pinus radiata D. Don. Because forest yield exceeds demand much of the expanding forest production is available for export. Analysis of the export potential for forest products has shown that wood quality will be important to market success. Yet there is concern that intrinsic properties will decline after 1985 with an inevitable reduction in rotation age. This work develops parameters which link silviculture to the two most important intrinsic properties, wood density and tracheid length. Both of these properties vary more or less regularly with geographic region. Within individual trees values depend on wood-age (= rings from pith). The properties of a stand of trees can be assessed if volume per tree can be partitioned into wood age categories. The parameter suggested here as best indicating wood quality whilst also having relevance to silviculture is volume of mature-wood, that is volume of wood age greater than ten years. A replicated spacing/thinning trial of 75, 0.06ha plots provided the data source. Models were developed to predict the wood quality parameter. Diameter growth is projected for a plot by means of an individual tree, distance dependent model based on multiple linear equations. Height is predicted from age and diameter by a system of homologous non-linear equations and volume per tree by a function of diameter squared and height. From diameter, height and age, mean wood age is predicted using a multiple linear equation and the distribution of volume by wood age is predicted using the Weibull function. The distribution is applied to each tree and totalled for the stand. Comparing results at a fixed age for a wide range of silvicultural regimes reveals that silviculture has a greater influence on wood quality than hitherto believed.
146

Decentralising forest management in India : the case of Van Panchayats in Kumaun

Baumann, Pari Christina January 1997 (has links)
This thesis is an examination of the political settlement in Indian forest policy. In the last two decades the rapid degradation of Indian forests has led to a reconsideration of who should manage the forests and with what priorities. An agenda has emerged which identifies the decentralisation of resources to local communities for subsistence as a national priority. This thesis explores the content and development of the consensus over decentralised forest management. My focus in this respect is on a system of common property forest management in the Central Himalaya, and on two villages in District Kurnaun in particular. In chapter 1 argue that the content of agenda is determined by two interest groups, the government and 'a social forestry interest group', comprised of NGOs ahd the international development community. Both have theories about the interaction between environment and society in which their own specific interests are represented as being in the general interest of society as a whole. The 'conventional' position adopted by the government considers central control over local units of management necessary to prevent unrestrained resource use. The 'populist' position of the social forestry interest group maintains that common property regimes were a past tradition, and that their disruption - is a principle cause for deforestation. Both theories fail to explore the material causes for environmental degradation, and the way in which local communities have adapted their patterns of resource use and social relations of production in response to developments in the wider economy. In chapter 3, 5, 6 and 7 I show the inadequacies of populist and conventional explanations for the interaction between environment and society, and why the new agenda fails to offer a comprehensive agenda for development. In chapter 4 and 8 I consider the way in which the discourse over the environment has become entrenched in policy making.
147

A comparison of the environmental effects of traditional intensive forestry and the sustainable forestry initiative: a modeling approach at the landscape level

Azevedo, Joao Carlos 30 September 2004 (has links)
Changes in landscape pattern caused by changes in forest management, namely the Sustainable Forestry Initiative (SFI), and the implications of these structural changes on landscape processes were analyzed. Landscape structure was studied based upon the comparison of landscapes with different management histories. Ecological processes were analyzed based upon simulation of stand and landscape attributes of habitats for several vertebrate species and upon simulation of hydrological processes such as water and sediment yield. A methodology to integrate landscape and stand pattern and dynamics with landscape processes was developed for this work. It integrates a forest landscape structure model, several stand level growth and yield models, vertebrate habitat models, and a hydrological model. The comparisons among landscapes revealed that forest management has a strong influence on landscape structure. The SFI program increases fragmentation of the landscape indicated by the presence of more and smaller patches, more edges, more complex shapes, and less and smaller core areas. Traditional intensive and extensive management show comparable patterns characterized by high aggregation and connectivity. Landscapes managed according to the SFI program show higher Habitat Suitability Index (HSI) values for American woodcock, American beaver, wild turkey, fox squirrel, and gray squirrel. HSI is higher for pine warbler in the landscape not managed according to the SFI program. Downy woodpecker and barred owl present very reduced HSI values in either landscape. The SFI program induced fragmentation of the habitat of pine warbler and the establishment of narrow and elongated habitats in a network structure for the remaining species. Both patterns are determined by SMZs. The scenario representing management according to the SFI program presents higher sediment yield at the watershed level than the scenario representing management not according to the SFI program due to higher channel erosion related to the absence of buffer strips in the non-SFI scenario. In general, management according to the SFI program increases landscape diversity and evenness, habitat suitability for most species, potential vertebrate diversity, and provides habitat structure suitable for most species. This management also decreases sediment loss at the watershed level.
148

A comparison of the environmental effects of traditional intensive forestry and the sustainable forestry initiative: a modeling approach at the landscape level

Azevedo, Joao Carlos 30 September 2004 (has links)
Changes in landscape pattern caused by changes in forest management, namely the Sustainable Forestry Initiative (SFI), and the implications of these structural changes on landscape processes were analyzed. Landscape structure was studied based upon the comparison of landscapes with different management histories. Ecological processes were analyzed based upon simulation of stand and landscape attributes of habitats for several vertebrate species and upon simulation of hydrological processes such as water and sediment yield. A methodology to integrate landscape and stand pattern and dynamics with landscape processes was developed for this work. It integrates a forest landscape structure model, several stand level growth and yield models, vertebrate habitat models, and a hydrological model. The comparisons among landscapes revealed that forest management has a strong influence on landscape structure. The SFI program increases fragmentation of the landscape indicated by the presence of more and smaller patches, more edges, more complex shapes, and less and smaller core areas. Traditional intensive and extensive management show comparable patterns characterized by high aggregation and connectivity. Landscapes managed according to the SFI program show higher Habitat Suitability Index (HSI) values for American woodcock, American beaver, wild turkey, fox squirrel, and gray squirrel. HSI is higher for pine warbler in the landscape not managed according to the SFI program. Downy woodpecker and barred owl present very reduced HSI values in either landscape. The SFI program induced fragmentation of the habitat of pine warbler and the establishment of narrow and elongated habitats in a network structure for the remaining species. Both patterns are determined by SMZs. The scenario representing management according to the SFI program presents higher sediment yield at the watershed level than the scenario representing management not according to the SFI program due to higher channel erosion related to the absence of buffer strips in the non-SFI scenario. In general, management according to the SFI program increases landscape diversity and evenness, habitat suitability for most species, potential vertebrate diversity, and provides habitat structure suitable for most species. This management also decreases sediment loss at the watershed level.
149

THE USE OF PRODUCTION ECONOMICS TO ALLOCATE RESOURCES IN TIMBER AND HERBAGE PRODUCTION

Burde, John Henry, 1946- January 1974 (has links)
No description available.
150

Public preferences for SFM: Case studies in tenure policy and forest certification

Kruger, Christopher Reinhard Unknown Date
No description available.

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