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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.
261

Value-added to Small-Diameter Timber (Obtained from Hardwood Plantations)

Ting-Ho Tsai (17549595) 05 December 2023 (has links)
<p dir="ltr">Thinning operations play a crucial role in ensuring forest health and sustainability. It strategically removes weaker trees and enhances overall growth by providing more essential resources such as sunlight, nutrients, and water. Small-diameter timber (SDT) is generally a byproduct of thinning operations in natural or plantation forests from either softwood or hardwood species. SDT is characterized by a diameter at breast height (DBH) of less than 9 inches for softwood and 11 inches for hardwood species.</p><p dir="ltr">Plantation forests contribute significantly to uniform material resources, needed for sustainable timber production. However, using SDT is often challenging because of the high cost of management, thinning operation, and its intrinsic characteristics, such as decreased wood properties due to the presence of juvenile wood and defects. Economic difficulties are especially evident for hardwood plantation owners because of the longer growth period of hardwoods.</p><p dir="ltr">This study explores feasible methods to enhance the value of hardwood SDT, encouraging its utilization and aiding plantation owners in offsetting management and thinning operations costs before the harvest of large-diameter timber. There are three parts: exploring potential products based on semi-products, conducting a case study by producing school furniture from six walnut SDTs, and providing recommendations for possible production from SDT.</p><p dir="ltr">Our investigation reveals strategic considerations for future school furniture producers. Establishing sorting and grading criteria, investing in more advanced machinery, producing edge-glued panels from SDT lumber, and having broader ideas for school furniture are pivotal for optimizing the SDT value-added process. The findings suggest that having a plan for the utilization of SDT, considering the recommendations provided, can elevate challenges, optimize strategies, increase the potential value of SDT from plantations, and promote sustainable and profitable use of forest resources.</p>
262

Forest resources and forestry in Vietnam: Review paper

Luong, Thi Hoan 09 December 2015 (has links)
Forest and forestland are important roles and sources of livelihood for the population living in or near forests and in mountainous areas of Vietnam. The objectives of this paper analysed the change in forest resource, and policy of forestry in Vietnam. In recent several years, forest area rapidly covered an average rate of 240,000 ha/year and had about 13.39 million hectares in 2010. It has contributed to the use of bare land, job creation and improvement of livelihoods for 25% of Vietnam’s population living in mountainous areas. Those results were the purpose of reforestation program and the production of wood industry in Vietnam. In this addition, government policies and regulations have provided a solid foundation for development of the forest plantations and conservation of forest ecosystems though forest land allocation and lease to organizations, households, and individuals. Therefore, the forest utilization has motivated by both environmental and commercial factors in Vietnam based on dividing into three forest categories special use, protection and production forests. However, the development strategy of forest management plan is the difficulties associated with conflicting land claims and boundary disputes due to the value of the established forest. / Rừng và đất rừng đóng vai trò quan trọng và là nguồn sinh kế cho người dân sống trong hoặc gần rừng ở các khu vực miền núi của Việt Nam. Mục tiêu của nghiên cứu này phân tích sự thay đổi về tài nguyên rừng và chính sách về lâm nghiệp. Trong một vài năm gần đây, diện tích rừng bao phủ nhanh với tốc độ trung bình 240.000 ha/năm và có khoảng 13,39 triệu ha trong năm 2010 này đã góp phần vào việc sử dụng đất trống, tạo việc làm và cải thiện đời sống cho 25% dân số sống ở khu vực miền núi của Việt Nam. Kết quả này là mục đích của chương trình trồng rừng và sản xuất gỗ công nghiệp tại Việt Nam. Bên cạnh đó, chính sách và các quy định của chính phủ đã cung cấp một nền tảng vững chắc cho việc phát triển diện tích trồng rừng và bảo tồn hệ sinh thái rừng mặc dù rừng và đất rừng đã được giao và khoán cho các tổ chức, hộ gia đình, cá nhân. Vì vậy, việc sử dụng rừng đã thúc đẩy bởi hai yếu tố môi trường và thương mại ở Việt Nam, dựa trên phân loại rừng: rừng đặc dụng, rừng sản xuất và rừng phòng hộ. Tuy nhiên, chiến lược kế hoạch quản lý phát triển rừng có những khó khăn liên quan đến xung đột khiếu nại đất và tranh chấp biên giới do giá trị của rừng được thành lập.
263

Integration of Photovoltaic Thermal Technology in the Greenhouses (A case study of Greece and Portugal)

Shah, Syed Aman January 2022 (has links)
The thesis work was done as a part of the company's proposal writing work for the Horizon Europe projects, which is the European Union's key funding program for research and innovation with a budget of €95.5 billion. The budget for this project call was €5 million and aimed towards demonstrating the possibilities of Photovoltaic thermal technologies (PVT), which will produce heat and electricity at the same time on agricultural land to combat climate change. The initial stage of the project, which the thesis work corresponds to, consists of the concept of implementing the objectives of the call and demonstrating how it could be achieved by forming a consortium of different companies, allocating the sites, possible applications of the PVT technology, understanding the plants which can grow in the relevant climate conditions under the shading of the panels. There are different companies who participate in the project call and, if they succeed, are liable to demonstrate the objectives of the call under the allocated budget and share the results with the European Union. The thesis work tried to focus on the company's objective for the call, which was to find out the suitable crops to be planted under the integrated PVT greenhouses, details on the weather conditions and applications of heat and electricity on the demonstration sites, i.e., Greece and Portugal. The emphasis was also given to creating a business canvas model and doing the strengths, weaknesses, opportunities, and threats (SWOT) analysis to make a business plan for this project. In this project, an Absolicon X10 PVT collector has been proposed with thermal heat up to 75 ºC and electricity at 230V. The outcomes also showed that each PVT collector integrated into the greenhouse could produce 4.73 MWh/year of thermal energy and can supply 2.2 MWh/year of electrical energy, which can save up to 0.48 tons/year of oil equivalent and avoid 37.6 tons of CO2 emissions during its lifetime of 25 years compared to burning oil. Considering the weather conditions in Greece and Portugal and to make sure the plants do not need much shading, tomatoes, barley and cacao seeds were identified as the potential crops to be planted in the PVT-integrated greenhouses.
264

Living History as Peformance: An Analysis of the Manner in which Historical Narrative is Developed through Performance

Mateer, Shelley Megan 13 January 2006 (has links)
No description available.
265

The socio-economic contributions of large-scale plantation forests: perceptions of adjacent rural communities in the Northern Province of Sierra Leone

Kainyande, Aruna, Auch, Eckhard F., Okoni-Williams, Arnold D. 31 May 2024 (has links)
The rapid demand for wood products globally has put pressure on natural forests. Therefore, global efforts are now being directed toward establishing plantation forests to fill the wood supply gap while reducing the pressure on natural forests. This study conceptualized the socio-economic contribution of large-scale plantation forests to adjacent rural communities in the Northern Province of Sierra Leone based on the local perceptions of 125 households interviewed during data collection. To complement the household survey data, two forest-plantation experts were interviewed. The study found that local communities mainly benefit from plantation forestry through employment, improved road conditions, and water well constructions. However, the delivery of these benefits differed among the communities depending on the spatial distance from the plantation forestry central office. Benefits related to improvements in road conditions were perceived higher in the more far away communities. The trend is similar for the perception of benefits from plantation forestry activities: the farthest community with limited opportunities for alternative livelihood options appreciated the plantation forestry benefits highly and as fairly distributed. The results further revealed that perceived benefits from the plantation forestry industry, specifically employment and income, were rather unevenly distributed because the elites were able to capture more benefits than the others. These people were also identified to be influential in the distribution of benefits from the plantation industry. It is suggested that the plantation industry makes a conscious effort to extend the delivery of benefits to more community members regardless of their landholding, social status, or education level to ensure equal access to employment and land lease income, as well as CSR benefits.
266

Physical and Hydrologic Responses of an Intensively Managed Loblolly Pine Plantation to Forest Harvesting and Site Preparation

Miwa, Masato 30 September 1999 (has links)
The Southeastern Lower Coastal Plain wet pine flats include thousands of acres of jurisdictional wetlands that are economically, socially, and environmentally important. These highly productive forests have been intensively managed as pine plantations for the past few decades. More recently, harvesting and site preparation practices have become a concern among natural resource managers because intensive forestry practices may alter soil physical properties and site hydrology. These alterations could decrease seedling survival, growth, and future site productivity. However, the effects of soil disturbance on long-term site productivity and the effects of amelioration techniques on site hydrology are uncertain. The overall objectives of this study were (1) to characterize disturbed forest soil morphology and physical properties, (2) to assess their impact on the processes that control site hydrology and site productivity, (3) to determine effects of harvesting and site preparation on site hydrology, specifically on the overall hydrological balance and on spatial and temporal patterns of surface water storage. The study site is located in an intensively managed loblolly pine (Pinus taeda L.) plantation in the lower coastal plain of South Carolina. This study was established in winter 1991, and dry- and wet-weather harvesting treatments were installed in summer 1993 and winter 1994, respectively. Bedding and mole channel/bedding treatments were installed in both dry- and wet-harvested plots in fall 1995. Soil profiles were described for a recently disturbed, deeply-rutted area, and 2-year-old deeply-rutted and churned areas, bedded and undisturbed areas. Intact soil core samples and composite loose soil samples were collected from each morphological section for soil physical characterizations. Automated weather station and wells were used to collect continuous climatic and surface water level data since 1996. Surface water levels were monitored monthly on a 20 x 20 m grid of 1-m wells since 1992. Total groundwater heads were determined from differential piezometer measurements at high and low elevation places in each treatment plot. Soil profile descriptions and soil physical property measurements indicated that significant amounts of organic debris were incorporated into the surface horizons, and subsurface soil horizons showed significant soil structural changes and increased redoximorphic features caused by soil disturbance. The disturbed soil layers in recently created traffic ruts consisted of exposed and severely disturbed subsurface soils, but this layer was naturally ameliorated 2 years after the disturbance. Bedding site preparation had little amelioration effects on the physical properties of surface soil horizons because the surface horizons already had some incorporation of organic debris. Overall, the main consequence of bedding in a disturbed wet site was to increase the aerated soil volume. The bedding appeared to have little effect on disturbed subsurface horizons. Groundwater head in the study site was constantly higher than -25 cm during the study period, which caused groundwater inflow when the surface water level was low. Frequent fluctuation of the surface water level and constant water supply from the groundwater probably explain the high productivity of the study site. Results of the annual water balance showed that surface soil water storage changes were very small, and annual precipitation and potential evapotranspiration were approximately equal. Silvicultural practices and minor topography on the study site had significant effects on the water balance because they influenced surface water level. Surface water hydraulic gradient evaluation and multivariate cluster analysis indicated that micro-site hydrology and water flow patterns were significantly altered by wet-weather harvesting and bedding site preparation, but overall site hydrology was not altered. Evaluation of predicted surface water level indicated that micro-topography and precipitation patterns had significant influences on surface water levels during the site establishment period. These results revealed that the hydrologic components of wetland delineation are complex in the wet pine flatwoods. / Ph. D.
267

Untersuchungen zur genotypischen und phänotypischen Variabilität verschiedener Schilfklone (Phragmites australis)

Zemlin, Rüdiger 21 September 2004 (has links)
In der vorliegenden Arbeit werden Wachstum und Entwicklung von 10 Schilfklonen (Phragmites australis) verglichen, um die genotypische Determinierung verschiedener Eigenschaften sowie den Einfluss der Standortfaktoren auf diese Eigenschaften zu untersuchen. Dabei sollen Aussagen zum Bestehen unterschiedlicher Ökotypen beim Schilf abgeleitet werden. Die Untersuchungen erfolgten auf sechs Pflanzfeldern, die im Rahmen von Renaturierungsmaßnahmen an den Ufern der Berliner Gewässer Seddinsee, Langer See und Havel im Frühjahr 1995 angelegt wurden. Die Anpflanzung erfolgt am Land, das Schilf wuchs in das Wasser vor. Die Herkunftsorte der Schilfklone unterschieden sich in der Nährstoffversorgung, der Substratqualität und der Exposition. Die Ergebnisse ließen deutliche Unterschiede in der Morphometrie der Halme (Halmlänge, Halmdurchmesser, Blattfläche pro Halm), der Halmbiomasse und der Balance zwischen Halmdichten und Halmlängen (bzw. Trockenmassen) zwischen den einzelnen Schilfklonen erkennen. Da dies beim Wachstum unter vergleichbaren Standortbedingungen gefunden wurde, kann eine genotypische Determinierung dieser Eigenschaften vermutet werden. Es konnte ebenfalls ein starker Einfluss der Umwelt auf das Wachstum des Schilfs festgestellt werden. Allgemein waren die Wachstumsbedingungen im Wasser deutlich besser als am Land. Die höchsten Halmbiomassen der einzelnen Schilfklone wurden daher im Wasser erreicht (zwischen 0,7 und 2,1 kg Trockenmasse pro m²), während die Werte am Land geringer waren (zwischen 0,6 und 1,0 kg/m²). Obwohl sich die Schilfklone an ihren ursprünglichen Standorten deutlich in den Stickstoffgehalten der Halme unterschieden, ergaben sich auf den Pflanzungen keine Unterschiede zwischen ihnen. Im Gegensatz dazu lagen die N-Werte bei jedem Schilfklon im Wasser erheblich höher als am Land. Dies lässt folgern, dass die Stickstoffgehalte der Halme in erster Linie vom Stickstoff-Angebot am jeweiligen Standort abhängen. Insgesamt deuten die Ergebnisse darauf hin, dass die Schilfklone genotypische Unterschiede in verschiedenen Merkmalen aufweisen können. Eine mögliche Nutzung zu einer Verbesserung des Erfolges von Pflanzmaßnahmen wird diskutiert. / In this study, growth and development of 10 reed clones (Phragmites australis) were compared to investigate genetically determined differences in various characteristics as well as the influence of site conditions on these characteristics. In addition, conclusions on the existence of different ecotypes were to be drawn. The study was performed on six experimental fields, established for shore renaturation on the lakes Seddinsee, Langer See and on the river Havel in Berlin in spring 1995. The plantations were established ashore, the reed expanded into the water. The sites of origin of the clones differed in nutrient supply, substrate quality and shore exposition. The results showed distinct differences between the individual reed clones regarding the morphometrics of the shoots (shoot length, culm diameter, leaf area per shoot), standing crop and the trade-off between shoot length (or dry matter) and shoot density. The fact that these results were found with clones that had grown under comparable site conditions seems to suggest a genotypic determination of these characteristics. A strong influence of the environment on the growth of the reed could also be deserved. In general, the conditions for growth were better in water than ashore. The highest standing crops of the individual reed clones were reached in water (between 0.7 and 2.1 kg drymatter pro m²), while the values ashore were lower (between 0.6 and 1.0 kg/m²). Although the reed clones at their original sites were clearly different in the nitrogen content of shoots, no differences were observed on the experimental fields. In contrast, the N-values of each clone were higher in water than ashore. This suggests that the nitrogen content of the shoots depends primarily on the nitrogen availability at the specific site. The results overall suggest that reed clones could exhibit genetically determined differences in various characteristics. A possible practical use to increase the efficiency of further reed plantations is discussed.
268

Producing tea coolies? / Work, life and protest in the colonial tea plantations of Assam, 1830s- 1920s

Varma, Nitin 05 December 2013 (has links)
Als "Coolie" gilt gemeinhin der "ungelernte" Arbeiter. Das Anbieten von Leiharbeit hatte diverse präkoloniale Vorläufer. Im 19. Jahrhundert wurde der Versuch unternommen, den Begriff des "Coolies" durch diskursive Auslegungen und die Methoden einer "flexiblen-inflexiblen" Arbeit neu zu prägen. "Coolie"-Arbeit galt meist als ein Kompromiss zwischen der Vergangenheit (Sklavenarbeit) und der Zukunft (freie Arbeit/Lohnarbeit) und als Spagat zwischen beiden Systemen. Sie wurde als ein Übergangsstadium und Teil eines versprochenen Wandels dargestellt. Die Teeplantagen Assams nahmen wie viele andere tropische Plantagen in Südasien auch im 19. Jahrhundert offiziell ihren Betrieb auf. Ursprünglich wurden sie von lokalen Arbeitern betrieben. Erst in den späten 1850er-Jahren wurden die lokalen Arbeiter durch von außerhalb der Provinz importierten Arbeitskräften ersetzt, die in der historischen Literatur gemeinhin unproblematisch mit dem Begriff "Coolies" belegt werden. Durch eine Analyse des Übergangs von der lokal rekrutiert für "Kuli" Arbeit und durch eine Analyse seiner Einführung die Studie argumentiert, dass "Kuli" Arbeit wurde "produziert" in den Kolonialkapitalistischen Plantagen in Assam. Mein Anliegen besteht dabei ausdrücklich nicht darin, einen zügellosen kolonialen Kapitalismus nahezulegen, dessen Strategie es ist, "Coolies" zu definieren und hervorzubringen oder die historischen Umstände, Verhandlungen, Streitfragen und Krisen zu betonen. Ich versuche vielmehr, die Erzählungen vom plötzlichen Auftauchen des archetypischen Teeplantagen-"Coolies" (d.i. als importierter und unfreier Lohnarbeiter) zu hinterfragen und sein Erscheinen, sein Bestehen und seine Verlagerungen mehr im Sinne grundlegender und diskursiver Prozesse auszulegen. / “Coolie” is a generic category for the “unskilled” manual labour. The offering of services for hire had various pre-colonial lineages. In the nineteenth century there was an attempt to recast the term in discursive constructions and material practices for “mobilized-immobilized” labour. Coolie labour was often proclaimed as a deliberate compromise straddling the regimes of the past (slave labour) and the future (free labour). It was portrayed as a stage in a promised transition. The tea plantations of Assam, like many other tropical plantations in South Asia, were inaugurated and formalized during this period. They were initially worked by the locals. In the late 1850s, the locals were replaced by labourers imported from outside the province who were unquestioningly designated “coolies” in the historical literature. Qualifying this framework of transition (local to coolie labour) and introduction (of coolie labour), this study makes a case for the “production” of coolie labour in the history of the colonial-capitalist plantations in Assam. The intention of the research is not to suggest an unfettered agency of colonial-capitalism in defining and “producing” coolies, with an emphasis on the attendant contingencies, negotiations, contestations and crises. The study intervenes in the narratives of an abrupt appearance of the archetypical coolie of the tea gardens (i.e., imported and indentured) and situates this archetype’s emergence, sustenance and shifts in the context of material and discursive processes.
269

L'efficacité du broutage par les moutons pour la gestion de la concurrence des herbes adventices dans de jeunes plantations de conifères en Colombie-Britannique au Canada

Serra, Ruth 20 April 2018 (has links)
La gestion de la végétation par des moutons (GVM) ou Sheep Vegetation Management (SVM) est une méthode biologique de gestion de la végétation concurrentielle dans des plantations de conifères, relativement récente en Colombie-Britannique (C-B). La présente étude comporte un volet biologique et un volet économique. Le premier se concentre sur la réponse de la croissance de l’épinette hybride (Picea glauca x Picea engelmannii) après le broutage des moutons en comparant des sites pâturés et non pâturés. Le second consiste en une évaluation de la rentabilité du SVM selon le nombre de pâturages appliqués. Les résultats suggèrent que le pâturage favorise la croissance en longueur internodale de l’épinette hybride. Pour rendre la SVM rentable dans les plantations de conifères, il est nécessaire de raccourcir la période de rotation. Ainsi, ce mémoire permet de combler certaines lacunes existantes sur le sujet en vue de promouvoir cette méthode en C-B. / The Sheep Vegetation Management (SVM) is a relatively recent biological method to control competing vegetation in conifer plantations in British Columbia (BC). This study is structured into biological and economic components. The first is based on growth response of hybrid spruce (Picea glauca x Picea engelmannii) saplings to sheep grazing treatment through the comparison of grazed and ungrazed sites. The second is a profitability evaluation of SVM depending on the number of grazing treatments. Results suggest that grazing improve intermodal length growth of hybrid spruce. To make SVM profitable method in conifer plantations, it would be necessary to shorten the rotational period. Hence, this thesis fills the gaps that still exist on the topic and promote the use of SVM in BC.
270

Réinventer l'espace forestier : ethnographie d'initiatives collectives de forêts nourricières et de plantations climatiques dans le Bas-Saint-Laurent, Québec

Giroux-Works, Nakeyah 24 January 2024 (has links)
Titre de l'écran-titre (visionné le 22 janvier 2024) / Cette thèse porte un regard anthropologique sur des initiatives collectives de plantation de végétaux réalisées dans la région du Bas-Saint-Laurent, Québec. Les initiatives étudiées mènent 1) à la création d'aménagements comestibles appelés « forêts nourricières » ou 2) à la réalisation de plantations d'arbres à des fins de compensation carbone volontaire, que j'ai nommées des « plantations climatiques ». Portées par différents groupes d'acteurs de la société civile (citoyens, professeurs, municipalités, organismes environnementaux, etc.), ces initiatives misent sur des approches de la conservation et de la valorisation environnementale basées sur des actions collaboratives, des attitudes de convivialité et de solidarité, et des économies déployées dans une perspective de transition socio-écologique. En m'appuyant sur une ethnographie multisites, j'explique comment la réalisation de ces projets agroforestiers se basent sur des idéaux de la forêt et des besoins en matière de lutte contre les changements climatiques, de protection de la biodiversité, de verdissement et de résilience alimentaire. L'approche de l'écologie politique permet de situer les contextes d'émergence de ces deux types d'initiatives, de rendre compte des dynamiques de pouvoir qui accompagnent leur création, et d'exposer leurs implications pour la construction et l'appropriation de l'espace forestier bas-laurentien. Cette thèse contribue à élargir les thématiques de recherche investies en anthropologie de la forêt au Québec, qui touchent généralement les aires protégées étatiques, l'industrie forestière et les questions autochtones. Elle met en lumière des modes d'exploitation des arbres et des plantes qui impliquent de valoriser, d'une part, des produits autres que le bois et, d'autre part, des espaces environnementaux « non productifs », comme des friches et des terrains déboisés, en mobilisant des imaginaires forestiers. Également, cette thèse vient poursuivre les recherches anthropologiques documentant les nouvelles manières de vivre et de s'engager sur le territoire rural du Bas-Saint-Laurent, en se penchant sur les aspirations socio-environnementales, locales et régionales, qui justifient les actions des groupes d'acteurs étudiées. / This thesis takes an anthropological look at collective vegetation planting initiatives carried out in the Bas-Saint-Laurent region, Quebec. The initiatives studied lead to the creation of 1) edible arrangements called "food forests" or 2) tree plantations for voluntary carbon offset purposes, which I have named "climatic plantations". Carried out by various groups of civil society actors (citizens, professors, municipalities, environmental organizations, etc.), these initiatives rely on approaches to conservation and environmental enhancement based on collaborative actions, attitudes of conviviality and solidarity, and economies deployed in a perspective of socio-ecological transition. Based on a multi-site ethnography, I explain how the realization of these agroforestry projects is based on the ideals and needs of the forest in terms of combating climate change, protecting biodiversity, greening and food resilience. The approach of political ecology allows to situate the contexts of emergence of these two types of initiatives, to account for the power dynamics that accompany their creation, and to expose their implications for the construction and appropriation of the Bas-Saint-Laurent forest area. This thesis contributes to broadening the research themes invested in anthropology of the forest in Quebec, which generally touch on state protected areas, the forestry industry and indigenous issues. It highlights modes of exploitation of trees and plants that involve valuing products other than wood and "non-productive" environmental spaces, such as fallow and lands, by drawing on forest-inspired imaginaries. Also, this thesis continues anthropological research documenting new ways of living and engaging in the rural territory of Bas-Saint-Laurent, focusing on socio-environmental aspirations, local and regional, which justify the actions of the groups of actors studied.

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