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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

Responding to climate change : policy integration and the Indonesian forestry sector

Suwarno, Yogi January 2017 (has links)
Literature on the integration of cross-cutting issues, or policy integration, has given little attention to how policy-making processes allow for policy integration as well as present barriers. There is also little evidence of how sectoral ministries respond to crosscutting issues and in what way they are affected by pressure to address such issues, including those promoted by ‘competing’ agencies. Climate change presents a significant and important issue for integration into many areas of public policy. Many government ministries and departments are tasked with responding to climate change mitigation and adaptation objectives. Forestry is a key sector in building a response to climate change and so an investigation into how policy-makers and policy-making processes have responded to climate change can shed light on the integration of cross-cutting issues. The thesis reports on investigation into how the Ministry of Forestry, Indonesia, has responded to climate change and into the organisational arrangements developed in the response to climate change. The research developed an innovative framework for the analysis of policy integration, generating conclusions in relation to the policy process, organisational arrangements and the influence of key actors, including policy champions and boundary spanners.
32

Variables affecting the stiffness and distortion of Sitka spruce

Reynolds, Timothy N. January 2010 (has links)
Inherent in the structure of timber are features affecting dimensional stability, stiffness and strength. These include knots, compression wood and spiral grain. Physical characteristics such as log shape, density, rate of growth, presence of juvenile wood and microfibril angle also affect these properties and, in turn, utilisation. In this thesis, the relationships between tree, log and board variables to the properties of stiffness and distortion of British-grown Sitka spruce (Picea sitchensis) are examined. The research‟s main aim was to identify variables which could potentially be used to sort timber. Different behaviour in terms of the relationship between stiffness and variables such as density, knot content, log taper, tree height and axial position were noted between groups of upper log and butt log material, and between the four stands and two sites studied. Relationships between stiffness and these variables were generally weak, notably for density. Overall, variables based on radial position within the stem were not found to be useful sorting parameters. No relationship between batten stiffness and compression wood content or slope of grain was observed. The relatively low stiffness of butt wood material was associated with high microfibril angle. Batten twist was found to be a function of spiral grain angle and distance from pith. However, practical difficulties with the use of slope of grain measurements to sort timber were noted. Although severe forms of compression wood were seen to be associated with stem-form correction, relatively straight logs and those which were round, or without pith eccentricity, were also observed to contain compression wood and hence yield timber which distorted on drying. In particular, this work demonstrates the effect of sorting timber using combined variables (e.g. log shape and knot content). These findings may be of use to foresters, sawmillers and developers of timber scanning technologies.
33

The effects of drying on the dimensional stability of spruce wood

Canavan, James W. January 2017 (has links)
Sitka spruce (Picea sitchensis (Bong.) Carr.) has been the most common forestry species in UK plantations for many decades. It is generally fast grown in short rotation, which has implications for quality. The harvested timber has a number of end-use applications. Of these, sawn construction grade timber is at the high end of market value. Currently, under one third of home grown sawn timber processed by sawmills achieves the required C16 or higher grading for construction class timber. Presently there is significant standing stock of 40 years old or under. Improvements in timber quality would create significant benefits for growers and processors. Distortion in kiln dried sawn timber is a considerable barrier to improving grading classification and marketability. Twist in particular accounts for around six percent of the rejections after kiln drying. Additional twist when timber dries further; in storage, at construction sites or in-service, is perceived as a marketing issue. The focus of this work was to better understand the evolution of twist during the drying process and seek to improve quality by examining the key properties in sawn timber that contribute to the formation of twist. Samples of regularly processed full size (3 m in length) sawn timber were kiln dried with no restraint to promote maximum twist. This was done in three stages to assess the impact of intermittent drying. Measurements of twist, moisture content, acoustic velocity and basic dimensions were taken before and after each drying cycle. The results showed highly significant differences between battens containing the pith and those that did not. Drying in stages did not seem to affect the linearity of the moisture content against twist relationship. Twist was seen to develop at a consistent rate throughout the process regardless of the final amount of twist accrued or the position from which the batten was sawn. Where timber is likely to dry to lower moisture content after sale it is therefore possible to predict the additional twist from the moisture content expected and allow for it by stricter grading than the twist standard demands. Twist was seen to decrease slightly during a lengthy period of storage in controlled conditions between drying cycles. This may allude to a relaxation effect which could have implications for timber distortion in-service but this would require a more extensive study before any such conclusions could be drawn. A second batch of unrelated samples, were kiln dried to 12% MC under restraint. All of these samples contained the pith along their length and all developed significant amounts of twist. This suggests that battens containing the pith will twist regardless of restraint. A method was developed to measure longitudinal shrinkage. This required the batten size to be reduced to fit the method and battens were sawn into 3 x 1 m sections. Battens were re-saturated and measured daily throughout air drying until an equilibrium moisture content was achieved. Measurements of transverse shrinkage were also taken concurrently. No relationship could be found between the longitudinal and transverse results. When plotted against the data for twist a positive relationship was found with longitudinal shrinkage. Acoustic tools were used to calculate dynamic stiffness. As the values for acoustic velocity squared correlated well with dynamic stiffness, other possible relationships were explored. Good agreement was found with twist and longitudinal shrinkage. This suggests it may be possible to predict twist in sawn timber directly or as a function of microfibril angle, using acoustic tools. A simple method for measuring grain angle was devised. Discs taken from the trees used in the drying experiment were measured for grain angle to compare with other measured properties. The measurement method worked well but the sample size was small and the discs too thin to provide good quality data quality. The results were not as instructive as expected. A vague relationship with twist was found. A repeat of the experiment with an improved method could yield more conclusive results. A method was developed to measure radial and tangential shrinkage in discs. Discs of Sitka spruce from a different source were used. Discs were saturated and allowed to dry with the expectation of cracks developing. The intention was to explore the nature of internal stresses present in intact discs and why tangential and radial shrinkage differs. As only one disc cracked the scope of comparison was limited but it was apparent that the greater shrinkage tendency in the tangential direction was responsible for radial cracking.
34

Distributional modelling in forestry and remote sensing

Wang, Mingliang January 2005 (has links)
The use of distributional models in forestry is investigated, in terms of their capability of modelling distributions of forest mensurational attributes, for modelling and inventory purposes. Emphasis is put on: (i) the univariate and bivariate modelling of tree diameters and heights for stand-level modelling work, and (ii) heuristic methods for use and analysis of distributions which occur in multi-temporal EO imagery, (for the inventory-related tasks of land-use mapping, change detection and growth modelling). In univariate distribution modelling, a new parameterization of the widely-used Johnson’s SB distribution is given, and new Logit-Logistic, generalised Weibull and the Burr system (XII, III, IV) models are introduced into forest modelling. The Logit-Logistic distribution is found to be the best among those compared. The use of regression-based methods of parameter estimation is also investigated. In the domain of bivariate distribution modelling of tree diameters and heights the Plackett method (a particular form of copula) is used to construct Plackett-based bivariate Beta, S­B and Logit-Logistic distributions, (the latter two are new), which are compared with each other and the SBB­ distribution. Other copula functions, including the normal copula, are further employed (for the first time in forest modelling) to construct bivariate distributional models. With the normal copula, the superiority of the Logit-Logistic in the univariate domain is extended into the bivariate domain. To use multi-temporal EO imagery, two pre-processing procedures are necessary: image to image co-registration, and radiometric correction. A spectral correlation-based pixel-matching method is developed to “refine” manually selected control points to achieve very accurate image co-registration. A robust non-parametric method of spectral-distribution standardization is used for relative radiometric correction between images. Finally, possibilities for further research are discussed.
35

The natural history, non-invasive sampling, activity patterns and population genetic structure of the Bornean banteng Bos javanicus lowi in Sabah, Malaysian Borneo

Gardner, Penny January 2014 (has links)
The banteng (Bos javanicus lowi) is an endangered wild bovid that is endemic to the island of Borneo. Within their last stronghold, the Malaysian state of Sabah, their population is believed to be less than 500 individuals, which are threatened with extinction by habitat loss and hunting. The banteng is highly elusive and rarely seen, and their preference for dense and remote tropical forest habitat makes them a highly challenging species to study. No extensive quantitative surveys have been undertaken in Sabah, and there is little information available to underpin their conservation and management. This thesis provides the first baseline data on the Bornean banteng in Sabah using ecological and molecular techniques. In Chapter 2, I created the first extensive natural history account of the banteng, which will help further the knowledge of this species. This compilation helped identify gaps in the knowledge, which were then addressed by this thesis. In Chapter 3, I test non-invasive survey techniques and individual identification, and estimate the population size in two forest reserves. In Chapter 4, I demonstrate that logged forests undergo dramatic changes in structure and ambient temperature, and that banteng mitigate these changes by altering their behaviour to avoid thermal-stress. Chapter 5 presents new information of the population genetic structure of banteng in four forest reserves in Sabah. Using mitochondrial markers I show that the ancestral lineage of the Bornean banteng reinforces the suggestion that they should be recognised as a separate subspecies to the Burmese and Javan banteng. I also show that the banteng experienced a population expansion following their colonisation of Borneo, and that the present genetic diversity indicates the population may be managed as two geographically-distinct units. Chapter 6 summarises the main findings of this thesis and the implications for the conservation of the Bornean banteng in Sabah.
36

A social and economic history of the Blackmount Deer Forest, Argyllshire, 1815-1900

Doogan, Brian January 2004 (has links)
Scottish deer forests are mainly a Highland phenomenon. Many were formed during the nineteenth century when proprietors benefited from their economic marketability as 'sporting estates'. The Blackmount area was a forest, under the ownership of the Campbells of Glenorchy, since the fifteenth century. Situated in one of the most mountainous ranges of the west Highlands, its function was to serve as a hunting reserve for both that family and their aristocratic peers, whilst being protected by foresters from poachers and trespassers. The earlier Forest of Corrie Ba ceased to exist during the later eighteenth century when sheep farming became the predominant land use there. Blackmount Forest was re-formed anew in 1820 due to an economic recession after the Napoleonic Wars terminated. This thesis identifies the social, political, economic, geographical and environmental reasons for Blackmount Forest's creation, growth and continued existence. It questions if this was for leisure alone or for a commercial ethos adopted by landlords of other forests. The Forest expanded during the nineteenth century, gaining national recognition, especially in the 1840s-1850s and thereafter. However, the Campbells of Breadalbane faced internal and external challenges and criticisms, several of a legal nature. The family were long established, in the Scottish aristocracy, with extensive estates in the west-central Highlands. The retained Blackmount for themselves, excepting the period 1863-1885 when it was let out wholesale. The thesis also identifies its social impact upon the locality, and the extent to which this forest may have influenced others coming into existence later that century.
37

Ways of knowing of farmers and scientists : tree and soil management in the Ethiopian Highlands

Habermann, Birgit January 2014 (has links)
The Ethiopian Highlands have been studied extensively, hosting a large amount of research for development projects in agriculture and forestry over several decades. The encounters in these projects were also encounters of different ways of knowing that were negotiated by the actors meeting in the space provided by the projects. This research explores these encounters and the social worlds they are embedded in, drawing on actor-oriented approaches as well as theories of narratives and framing. Ways of knowing and citizen epistemologies are taken as a lens to understand the role of identities in knowledge production and use. The two case studies were agroforestry research projects in the Ethiopian Highlands. The research followed a range of qualitative and ethnographic research methods. Different types of farmers and scientists meet in the case studies. I recognise that they all have individual agency, nevertheless I use the terms ‘scientist' and ‘farmer' in this thesis. I use the terms to describe certain groups of actors who all draw on different ways of knowing, and different value systems, when interacting with each other and their environment. The results indicate that the importance of social worlds at different scales and the contexts of research projects tend to be underestimated. In spite of good intentions scientific methodologies, terminologies and narratives tend to dominate. Scientists in the case studies acknowledged the existence of farmers' ‘indigenous' knowledge, but they determined the value of knowledge by its scientific applicability and the replicability of experiments. Research systems force the scientists into a certain modus operandi with limited possibilities to experiment and to respond to the complexities and diversities of people's social worlds. Farmers in the case studies preferred observation from their parents, observing from others or the environment as a way of learning and gaining knowledge. Depending on their personalities and their life histories they also relied on alternative ways of knowing rooted in spirituality, emotions and memories. Powerful influences on ways of knowing resulted from the way languages and authority had been used. These often led to the exclusion of marginalised community members from access to knowledge and technologies. Unfortunately, common narratives prevailed in the case studies, and alternative ways of knowing were often marginalised. By acknowledging different ways of knowing and the importance of different social worlds and different ways of doing research, both scientists and farmers could benefit and develop more sustainable pathways for agricultural and forestry land use.
38

Poverty within tropical forest : assets and activities to develop pro-poor forest conservation

Perge, Emilie January 2011 (has links)
Poverty within forests is often acknowledged but poorly assessed through economic evi- dence. To some extent, this lack of evidence explains why even if forest conservation has positive effects on households' welfare, such benefits are quite limited. This thesis is aimed at investigating in three steps how forest conservation can help poor forest households to improve their welfare. A first chapter deals with assessing poverty of forest households in Bolivia looking at their asset accumulation and allowing for a poverty trap mechanism that may arise, preventing households to be better off. The empirical analysis does not find evidence for the exis- tence of a poverty trap. Households are slowly accumulating assets over time but such an accumulation does not lead to any improvements in their welfare. Households would remain persistently poor. A second chapter focuses on forest households' labour supply and allocations. Using primary data I collected in Cameroon, a non-separable agricultural household model is employed to identify factors influencing household labour supply and allocations into di- verse activities. The empirical results shows that leisure is an inferior good, households working more when having greater income. Furthermore, households participating in for- est activities have higher levels of welfare than households that do not. Increasing prices of forest resources helps households to improve their welfare. The last chapter deals with designing payments for forest conservation so as to encourage forest households to internalise externalities. These payments are theoretically analysed using a principal-agent game in order to define incentives such that a forest group plants and conserves a great number of trees. Payments are non-zero when observing such con- servation levels and equal to zero in all other cases. Doing so creates a virtuous circle on forest resources. Pro-poor conservation schemes as opposed to non-pro poor, are achiev- able with lower payments.
39

Improvement and the Scottish rural estate : Sir Archibald Grant at Monymusk, 1715-1778

Doroszenko, Rebekah January 2015 (has links)
The purpose of this study is ultimately to analyze the influence of cultural attitudes on the treatment of the Scottish estate in the first half of the 18th century (c.1715 – c.1776), making particular reference to the ideology of improvement, through the use of Sir Archibald Grant of Monymusk as a case study. Grant’s improvement of his estate is not understood as literally agricultural or economic development alone, but as a complex ideological commitment to the transformation of land, landscape and society. Whilst Grant of Monymusk has been discussed with reference to economic improvement, the relationship between his role as a publically acknowledged improver and his patronage of art and architecture, as well as his attempts at publication, has not been subject to similar interest. This thesis uses an innovative interdisciplinary approach which draws on archaeological as well as art historical methodologies. It discusses a wider range of estate commissions, in particular Grant’s patronage of the portrait artists John Smibert and William Robertson, the poet John Ogilvie, his commission of the architectural surveyors Alexander Jaffray and Robert Robinson, as well as his work to construct planned villages at Kirktown of Monymusk and Archiestown. The thesis attempts to place these commissions within the context of recent studies of improvement which emphasize its role as an ideology with cultural implications. The use of an individual case study allows for a more in depth discussion of specific reactions to historical and ideological change, providing a narrative of a specific site and thus creating an individual response towards broader cultural and scientific developments.

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