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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.
31

Draft forest management plan for Cashmere Forest, Port Hills, Canterbury /

Mansell, Jeremy. January 2006 (has links)
Thesis (M. For. Sc.)--University of Canterbury, 2006. / Typescript (photocopy). Includes bibliographical references (leaves 170-175). Also available via the World Wide Web.
32

The influence of introduced forest management practices on transformative social learning in a selected social-ecological forest community : a case of PFM and REDD projects at Pugu and Kazimzumbwi Forest Reserves in Tanzania

Ferdinand, Victoria Ugulumu January 2016 (has links)
This research investigates the influence of introduced forest management approaches on transformative social learning in the community surrounding the Pugu and Kazimzumbwi forest reserves in Tanzania from 2000 to 2015. The term transformative social learning reflects an understanding of learning processes that emerge through conscious changes in the perspectives of individuals or communities while interacting with forest management practices. The investigation explores the learning (if any) that occurred in the community and how and why the learning occurred. It also explores whether the learning was social and transformative and examines the conditions that enable or constrain transformative social learning at the Pugu and Kazimzumbwi community. Thus, the three concepts of social learning, transformative learning, and social practices are central to the research. Participatory Forest Management (PFM) emerged globally in the early 1980s to mobilise rural capabilities and resources in development and environmental stewardship. The Pugu and Kazimzumbwi community was introduced to Participatory Forest Management (PFM) projects by the late 1990s. The recent global focus on empowering communities around forests has drawn attention towards transformational adaptation to climate change impacts and building resilience capacities. As a result, in 2011 the Pugu and Kazimzumbwi community started working with a project for Reduction of Emissions through Deforestation and forest Degradation (REDD), which forms a key focus in this study as the most recently introduced PFM with embedded social learning assumptions. This research is designed and conducted as a qualitative case study. The research seeks to study the complex object of socially and contextually constructed learning through a systemic exploration of learning,using semi-structured interviews, focus group discussions, analysis of documents and archival records as well as observations and a reflexive workshop. Supportive information throughfield notes and audio voice and video recording was also generated. A contextual profile of the research site was conducted in March 2012, prior to the actual data collection in 2013 and 2014. Field explorations during the contextual profile helped to describe the research site and promote initial understanding of the context. During data collection, field inquiries based on interactive relationships between a researcher and participants stimulated practice memories and people’s living experiences with forestry and the introduced PFM projects under examination. Analysis of data employed analytical modes of induction, abduction and retroduction. Thick descriptions of learning obtained from fieldi based interactionswere produced before re-contextualising data through theoretical lenses. The research employed realist social theory by Archer (1995), under-laboured by critical realism, and practice theory advanced by Schatzki (2012) and Kemmis et al. (2014). The research process as a whole was underlaboured by the layered ontology of critical realism which proposes emergence of phenomena in open systems as shaped by interacting mechanisms which in this study were both material / ecological and social /political /economic /cultural. And more...
33

Statistical characterization of area and distance in arc-node geographic information systems

Prisley, Stephen P. January 1989 (has links)
While Geographic Information Systems (GIS) have proven to be effective tools for the management and analysis of forest resources data, estimates of the reliability of area and distance measures computed in GIS have been lacking. Using fairly weak assumptions regarding the variability of point location errors, expressions for computing the mean, variance and covariance of polygon area, and an approximate distribution for distance are derived. Assumptions about point location errors include unbiasedness, independence between X and Y coordinate errors, known and equal variance of errors in X and Y coordinates, and correlation between errors at adjacent points. For the derivation of distance from a point to a line, the assumption of normality of errors is added. Because the variance of polygon area that was derived depends on the location of the centroid, a centroid location which minimizes polygon variance was defined. After the mean and variance of polygon area errors were obtained, polygon area was shown to be approximately normally distributed in a simulation of errors in regular polygons. Distance between a point and a line consists of two cases: distance from the point to a vertex of the line, and perpendicular distance to a line segment. The square of vertex distance was shown to be distributed as a non-central chi-square random variable when normal errors are assumed. The normal distribution was demonstrated to be a reasonable approximation for perpendicular distance under similar assumptions. As an application of the polygon variance and covariance formulas, the variability of value of a tract of land was estimated, based upon fixed per-acre values and assumptions regarding variability of location errors. Under moderate assumptions of variability and correlation, the coefficient of variation of mean tract value was 8%. To demonstrate the application of the distribution of distance, a probabilistic point-in-polygon analysis was performed using timber cruise plot locations in a timber stand map. Over half of the plots were ambiguously located when evaluated using the most liberal set of assumptions tested. The advantages and disadvantages of the models developed herein are discussed. / Ph. D.
34

Forest industry restructuring and emerging forest tenures in Deschutes and Klamath Counties, Oregon /

Kelly, Erin Clover. January 1900 (has links)
Thesis (Ph. D.)--Oregon State University, 2010. / Printout. Includes bibliographical references (leaves 129-145). Also available on the World Wide Web.
35

The impact of subsistence use of forest products and the dynamics of harvested woody species populations in a protected forest reserve in Western Zimbabwe

Mudekwe, John 03 1900 (has links)
Thesis (PhD (Forest and Wood Science))—University of Stellenbosch, 2007. / Developing sustainable mechanisms for use-management of forest products by user communities has been suggested as a possible solution to the often-observed conflict between forest use and the conservation of protected forests. In Zimbabwe, the use of forest products in protected forests by local communities has a long history, but few studies have explored both the socio-economic and ecological aspects of this use. This study was conducted in the Baikiaea plurijuga forests and woodlands in and around Fuller Forest in western Zimbabwe, protected since 1943. It explored the characteristics and dynamics of forest products use by communities surrounding this protected forest. Further, the demography and dynamics of commonly harvested woody species was examined in order to establish the present status of populations of these species. This examination, focusing on diameter class distributions, was aimed at informing whether species populations were expanding, stable or declining in view of their capacity to continue providing required goods and services. Results indicated that all households, rich and poor, were harvesting at least some forest resources from the protected forest, with the most frequently harvested resources being firewood, wood for curios, thatch grass, wild fruits, timber for construction and fencing and those who owned livestock used the forest for livestock grazing. The extraction and use of 23 different products was recorded across the villages. The top five harvested forest products in terms of the mean proportion of households using them were fuelwood, building poles, thatch grass, wild fruits and broom grass. Forest products were harvested both for own consumption and for sale. At present Baikiaea plurijuga, Colophospermum mopane, Brachystegia spiciformis, Diplorhynchus condylocarpon, Commiphora mocambicensis and Bauhinia petersiana out of 14 commonly harvested species appear to have relatively stable populations as indicated by their inverse J-shaped diameter class distribution profiles. Preliminary indications from this baseline information point towards the successful integration of local use of forest products and conservation objectives noting that there is need for caution until further studies as recommended in this study are taken.
36

A conspiracy of optimism: Sustained yield, multiple use, and intensive management on the national forests, 1945-1991.

Hirt, Paul Wayne. January 1991 (has links)
This is a historical study of the intersection of political economy with natural resources management, as played out on the national forests between 1945-1991. Specifically, it focuses on two core national forest management policies; sustained yield and multiple use. These two policy directives represent an attempt by the public and elected officials to apply principles of sustainable development to publicly-owned forest lands, and to ensure that a wide variety of both market and nonmarket forest values are preserved for the benefit of present and future generations. Interest groups, the Forest Service, and policy makers have conceived of sustained yield and multiple use in different and evolving ways over the years. This study explores how these principles have been variously defined and either implemented or thwarted. After World War Two, with escalating demands on national forest resources, the U.S. Forest Service turned to "intensive management" as a technological method of enhancing natural forest productivity and mitigating the environmental effects of increased use. But the agency's optimistic vision of efficient, sustained production of forest commodities through technical mastery over nature has met overwhelming fiscal, environmental, technical, and political obstacles. Nevertheless, agency leaders, industry advocates, and politicians have consistently promulgated an optimistic faith that intensive applications of labor, capital, and technology can maximize and harmonize multiple uses, rehabilitate damaged resources, and sustain high levels of outputs in perpetuity--despite repeated failures to achieve balanced multiple use management and to manage grazing and timber extraction at sustainable levels. The conspiracy of optimism ideologically justifies continued unsustainably high levels of resource extraction. Changing public values since the 1960s and the popularization of ecology have initiated a growing skepticism toward the premises of intensive management. At the same time, field level forest managers have grown frustrated with top-down imposition of resource production quotas and the lack of adequate political, fiscal, and organizational support for sound forest management. As the last old growth forests fall to the chainsaw, and as the federal subsidies required to access these remote timber stands on the national forests escalate, public controversy deepens. In this decade of the national forest centennial a revolt of conscience has erupted among grassroots Forest Service personnel, and a strong challenge from the environmental community has gained momentum. Another major period of policy evaluation and revision appears to be taking place. Whether the conspiracy of optimism can continue to sustain the old status quo is questionable.
37

Sistemas agroflorestais para recuperação de matas ciliares em Piracicaba, SP. / Agroforestry systems for restoration of riparian forests in Piracicaba, SP.

Vaz da Silva, Patricia Pereira 09 April 2002 (has links)
A necessidade de recuperação de áreas ciliares degradadas tem subsídio na legislação, porém, o uso de sistemas agroflorestais para esse fim não é permitido. O objetivo desse trabalho é comparar a capacidade de recuperação de dois sistemas agroflorestais e de um plantio florestal com espécies arbóreas nativas, também avaliando as diferenças de custos de implantação e manejo. A pesquisa foi realizada no Estado de São Paulo, município de Piracicaba, às margens do Rio Corumbataí, na propriedade da Usina Costa Pinto, onde o cultivo de cana-de-açúcar ocupa a maior parte do uso do solo. Os tratamentos foram: (1) testemunha; (2) sistema florestal, com 10 espécies arbóreas nativas; (3) sistema agroflorestal simples, com as mesmas arbóreas nativas, guandu e feijão-de-porco como adubo verde; (4) sistema agroflorestal complexo, com diversas espécies frutíferas, girassol e capim napier, além das mesmas arbóreas nativas e das duas leguminosas. Os fatores mensurados foram: altura e diâmetro à altura do colo das arbóreas nativas, custos, liberação de CO2 do solo, biomassa microbiana e fertilidade do solo. O SAF simples apresentou as maiores alturas médias, com um aumento de 36% em relação ao sistema florestal. O SAF complexo apresentou resultados intermediários, com altura média 10% superior à do sistema florestal. Separando as espécies em pioneiras e não pioneiras, as primeiras não apresentaram diferença entre os tratamentos, tendo as não pioneiras crescido cerca de 35% melhor no SAF simples. Supõe-se que as leguminosas tenham cumprido a função de pioneiras, melhorando o ambiente e propiciando o melhor crescimento das não pioneiras. A média do diâmetro de todas as espécies para cada tratamento apresentou diferença entre o SAF simples (51% maior) e o SAF complexo, sendo ambos semelhantes ao sistema florestal, que foi intermediário. Entre pioneiras e não pioneiras, as diferenças foram semelhantes, sendo o SAF simples 67% superior ao SAF complexo, entre as pioneiras, e 33% superior entre as não pioneiras. As análises de solo, tanto de biomassa microbiana, liberação de CO2 ou de fertilidade, não mostraram diferenças entre os tratamentos. Numa estimativa com base nas modificações sugeridas a partir dos dados do experimento, o SAF simples pode ter um custo 16% inferior ao do sistema florestal, principalmente devido à redução da necessidade de manutenção do sistema. O SAF complexo apresentou o maior custo dos três tratamentos, pois, além da grande demanda de mão-de-obra, o sistema encontra-se fora dos padrões legais para venda de sementes. O estudo da heterogeneidade do ambiente reforça a necessidade do uso de métodos de implantação e de manejos diferentes para cada situação encontrada e permitiu inter-relacionar os blocos quanto à degradação, com base nas médias dos blocos, para todos os parâmetros avaliados. Seguindo critérios semelhantes, as espécies arbóreas nativas também foram ordenadas segundo a sucessão, de acordo com a teoria de Götsch: Sangra d’água, Embaúba, Cordia, Mutambo, Pau Viola, Tamboril, Trema, Canafístula, Aroeira, Canelinha. Em condições de grande fragmentação da matriz florestal e forte domínio de gramíneas, o uso de sistemas agroflorestais na recuperação de matas ciliares pode trazer efeitos positivos ao crescimento das árvores nativas e redução no custo de implantação. / Riparian forest is the vegetation that borders rivers, ponds and lakes, and although it is protected by law, agricultural systems are widely used in these areas. Restoration of deforested riparian zones is requested by law, but agroforestry systems are not accepted for this purpose. The objective of this research was to compare the restoration success and the costs of three kinds of restoration management systems: two agroforestry systems and one forestry system, intending to give basis for changes in public policies. This research was carried out in São Paulo State, Piracicaba County, in the Corumbataí River watershed, in the farm of Usina Costa Pinto, where sugar cane fills most of the lanscape. The treatments were: (1) control; (2) forestry system, with 10 native tree species; (3) agroforestry system 1, where two herbaceous/shrub legume species were included in addition to trees; (4) agroforestry system 2, were 10 edible fruit species, sunflower and napier grass were added. Management was evaluated by measuring height and diameter of the native tree species, soil respiration, microbial biomass and soil fertility. Comparing the mean height of all species, agroforestry system 1 showed the best results, which was 36% better than the forestry system. Agroforestry system 2 showed intermediate results: mean height was 10% higher than the one achieved in forestry system. When the species were grouped according to ecological succession, pioneers didn’t present any difference between treatments, but not-pioneers grew 35% better in agroforestry system 1. Probably, legume plants played the role of pioneers, improving the environment and supporting a better development of the non-pioneers. The mean diameter at ground level of all the species showed differences between agroforestry system 1 (51% better) and agroforestry system 2, but both were not different from the forestry system, which had intermediate results. There were similar differences when the species were grouped in pioneers and non-pioneers. For pioneers, agroforestry system 1 was 67% better than agroforestry system 2 and, for non pioneers, this difference was of 33%. There were no differences among treatments in soil fertility, microbial biomass and soil respiration. Estimating the costs, on the basis of modifications suggested after data analysis, agroforestry systems 1 may cost 16% less than forestry system, due to less necessity of interventions for weeds control. Agroforestry system 2 had the highest cost because it demanded much more work than other treatments and this system, like agroforestry system 1, is out of legal standard for seed production. Studies on the environment heterogeneity allowed to rank blocks, based on the block means of all the measured parameters. Based on the same principles, the native tree species were also ranked according to Götsch succession theory: Croton urucurana, Cecropia pachystachya, Cordia superba, Guazuma ulmifolia, Cytharexyllum myrianthum, Enterolobium contortisiliquum, Trema micrantha, Peltophorum dubium, Schinus terebinthifolius, Nectandra megapotamica. In conditions of high fragmentation of natural forests and high density of weeds, agroforestry systems may cause positive effects in riparian forests restoration, favoring better growing of native trees and lower costs of restoration.
38

Using place attachment to determine the acceptability of restoring fire to its natural role in wilderness ecosystems

Turbeville, Eric Paul. January 2006 (has links)
Thesis (M.S.)--University of Montana, 2006. / Title from PDF t.p. (viewed on Mar. 14, 2007). Includes bibliographical references (p. 112-117).
39

A history of the use and management of the forested lands in Arizona, 1862-1936

Lauver, Mary Ellen, 1904- January 1938 (has links)
No description available.
40

Draft forest management plan for Cashmere Forest, Port Hills, Canterbury

Mansell, Jeremy. January 2006 (has links)
Thesis (M. For. Sc.)--University of Canterbury, 2006. / Title from PDF title page (viewed on Feb. 9, 2008). Includes bibliographical references (leaves 170-175). Also issued in print.

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