954 resultados para Forest resource and environment


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Yhteenveto: Elohopea Suomen metsäjärvissä ja tekoaltaissa: ihmisen vaikutus kuormitukseen ja pitoisuuksiin kaloissa.

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‪This dissertation examines the impacts of energy and climate policies on the energy and forest sectors, focusing on the case of Finland. The thesis consists of an introduction article and four separate studies. The dissertation was motivated by the climate concern and the increasing demand of renewable energy. In particular, the renewable energy consumption and greenhouse gas emission reduction targets of the European Union were driving this work. In Finland, both forest and energy sectors are in key roles in achieving these targets. In fact, the separation between forest and energy sector is diminishing as the energy sector is utilizing increasing amounts of wood in energy production and as the forest sector is becoming more and more important energy producer.‬ ‪The objective of this dissertation is to find out and measure the impacts of climate and energy policies on the forest and energy sectors. In climate policy, the focus is on emissions trading, and in energy policy the dissertation focuses on the promotion of renewable forest-based energy use. The dissertation relies on empirical numerical models that are based on microeconomic theory. Numerical partial equilibrium mixed complementarity problem models were constructed to study the markets under scrutiny. The separate studies focus on co-firing of wood biomass and fossil fuels, liquid biofuel production in the pulp and paper industry, and the impacts of climate policy on the pulp and paper sector.‬ ‪The dissertation shows that the policies promoting wood-based energy may have have unexpected negative impacts. When feed-in tariff is imposed together with emissions trading, in some plants the production of renewable electricity might decrease as the emissions price increases. The dissertation also shows that in liquid biofuel production, investment subsidy may cause high direct policy costs and other negative impacts when compared to other policy instruments. The results of the dissertation also indicate that from the climate mitigation perspective, perfect competition is the favored wood market competition structure, at least if the emissions trading system is not global.‬ ‪In conclusion, this dissertation suggests that when promoting the use of wood biomass in energy production, the favored policy instruments are subsidies that promote directly the renewable energy production (i.e. production subsidy, renewables subsidy or feed-in premium). Also, the policy instrument should be designed to be dependent on the emissions price or on the substitute price. In addition, this dissertation shows that when planning policies to promote wood-based renewable energy, the goals of the policy scheme should be clear before decisions are made on the choice of the policy instruments.‬

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There is a large interest in biofuels in India as a substitute to petroleum-based fuels, with a purpose of enhancing energy security and promoting rural development. India has announced an ambitious target of substituting 20% of fossil fuel consumption by biodiesel and bioethanol by 2017. India has announced a national biofuel policy and launched a large program to promote biofuel production, particularly on wastelands: its implications need to be studied intensively considering the fact that India is a large developing country with high population density and large rural population depending upon land for their livelihood. Another factor is that Indian economy is experiencing high growth rate, which may lead to enhanced demand for food, livestock products, timber, paper, etc., with implications for land use. Studies have shown that area under agriculture and forest has nearly stabilized over the past 2-3 decades. This paper presents an assessment of the implications of projected large-scale biofuel production on land available for food production, water, biodiversity, rural development and GHG emissions. The assessment will be largely focused on first generation biofuel crops, since the Indian program is currently dominated by these crops. Technological and policy options required for promoting sustainable biofuel production will be discussed. (C) 2010 Elsevier Ltd. All rights reserved.

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The boreal forest of western Canada is being dissected by seismic lines used for oil and gas exploration. The vast amount of edge being created is leading to concerns that core habitat will be reduced for forest interior species for extended periods of time. The Ovenbird (Seiurus aurocapilla) is a boreal songbird known to be sensitive to newly created seismic lines because it does not include newly cut lines within its territory. We examined multiple hypotheses to explain potential mechanisms causing this behavior by mapping Ovenbird territories near lines with varying states of vegetation regeneration. The best model to explain line exclusion behavior included the number of neighboring conspecifics, the amount of bare ground, leaf-litter depth, and canopy closure. Ovenbirds exclude recently cut seismic lines from their territories because of lack of protective cover (lower tree and shrub cover) and because of reduced food resources due to large areas of bare ground. Food reduction and perceived predation risk effects seem to be mitigated once leaf litter (depth and extent of cover) and woody vegetation cover are restored to forest interior levels. However, as conspecific density increases, lines are more likely to be used as landmarks to demarcate territorial boundaries, even when woody vegetation cover and leaf litter are restored. This behavior can reduce territory density near seismic lines by changing the spatial distribution of territories. Landmark effects are longer lasting than the effects from reduced food or perceived predation risk because canopy height and tree density take >40 years to recover to forest interior levels. Mitigation of seismic line impacts on Ovenbirds should focus on restoring forest cover as quickly as possible after line cutting.

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Concern that European forest biodiversity is depleted and declining has provoked widespread efforts to improve management practices. To gauge the success of these actions, appropriate monitoring of forest ecosystems is paramount. Multi-species indicators are frequently used to assess the state of biodiversity and its response to implemented management, but generally applicable and objective methodologies for species' selection are lacking. Here we use a niche-based approach, underpinned by coarse quantification of species' resource use, to objectively select species for inclusion in a pan-European forest bird indicator. We identify both the minimum number of species required to deliver full resource coverage and the most sensitive species' combination, and explore the trade-off between two key characteristics, sensitivity and redundancy, associated with indicators comprising different numbers of species. We compare our indicator to an existing forest bird indicator selected on the basis of expert opinion and show it is more representative of the wider community. We also present alternative indicators for regional and forest type specific monitoring and show that species' choice can have a significant impact on the indicator and consequent projections about the state of the biodiversity it represents. Furthermore, by comparing indicator sets drawn from currently monitored species and the full forest bird community, we identify gaps in the coverage of the current monitoring scheme. We believe that adopting this niche-based framework for species' selection supports the objective development of multi-species indicators and that it has good potential to be extended to a range of habitats and taxa.

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This thesis contends that government focus on policy implicitly defines community education as a means of overcoming barriers to government-initiated change, rather than as an input to governmental decision-making. The role of education is thus viewed as instrumentalist rather than as dialectical in nature. I argue that this role has been reinforced and driven by economic rationalism, as a mechanism related to scientific theory and practice. The thesis addresses the role of government in non-institutional community-based environmental education. Of interest is environmental education under the dominance of economic rationalism and as expressed in government-derived policy, in its own right, and as enacted in two government funded animal management projects. The main body of data, then, includes a review of some contemporary environmental policies and two case studies of 'policy in practice'. Chapter One provides an overview of environmentalism as it has emerged as part of the discourse of Western political systems. Recognised as part of this change is a move to environmentalism embued with the rhetoric of economic theory. The manifestation of this change can be seen in an emphasis on management for the natural environment's use as a resource for humans. Education under this arrangement is valued in terms of its ability to support initiatives that are perceived as economically viable and economically advantageous, maintaining centralised control of decision-making and serving the interests of those who profit from this arrangement. Government-derived environmental policies are presented in Chapter Two. They provide evidence of the conjoining of environment with economic rationalism and the adoption of a particular stance which is both utilitarian and instrumentalist. Emerging from this is an understanding of the limitations placed on environmental debates that do not respond to complex understandings of context and instead support and legitimate centralisation of decision-making and control. Chapter Three presents an argument for an historical approach to environmental education research to accommodate contextual dimensions, as well as scientific, economic and technical dimensions, of the subject under study. An historical approach to research, inclusive of biographical, intergenerational and geographical histories, goes some way to providing an understanding of current individual and collective responses to policy enactment within the two study sites. It also responds to the concealing of history which results from the reduction of environmental debates to economic terms. With this in mind, Chapters Four and Five provide two historical case studies of 'policy in practice'. Chapter Four traces the workings of a rabbit control project in the Sutton Grange district of Victoria and Chapter Five provides an account of a mouse plague project in the Wimmera and Mallee regions of Victoria. The Sutton Grange rabbit project is organised and controlled by district landholders while the Wimmera and Mallee mouse project is organised and controlled by representatives from a scientific organisation and a government agency. Considered in juxtaposition, the two case studies enable an analysis of two somewhat different expressions of the 'role of government'. Chapter Six investigates the competing processes of community participation in governmental decision-making and Australia's system of representative democracy, Despite a call for increased community participation, the majority of policies remain dominated by governmental rhetoric and ideology underpinned by a belief in impartiality. The primacy of economics is considered in terms of government and community interaction, with specific reference to the emergence of particular conceptual constructions, such as cost-benefit analysis, that support this dominance. Of specific importance to this thesis is the argument that economic theory is essentially anthropocentric and individualist and, thus, necessarily marginalises particular conceptions of environment that are non-anthropocentric and non-individualistic. Finally, Chapter Six examines two major interrelated tensions; those of central interests and community interests, and economic rationalism and environmentalist. Chapter Seven looks at examples of theories and practices that fall outside the rationality determined by scientistic knowledge. It is clear from the examination of environmental policy within this thesis that the role ascribed to environmental education is instrumentalist. The function of education is often to support, promote and implement policy and its advocated practices. It is also clear from the examination of policy and advocated processes that policy defines community education as a means of manifesting change as determined by policy, rather than as an input to governmental decision-making. The domination of scientific, economic and technocratic processes (and legitimation of processes) allows only for an instrumentalist approach to education from government. What is encouraged by government through the process of change is continuity rather than reform. It promotes change that will not disrupt the governing hegemony. Particular perspectives and practices, such as a critical approach to education, are omitted or considered only within the unquestioned rationale of the dominant worldview. Chapter Seven focuses on the consequence of government attention to policy which implicitly defines community education as a means of overcoming barriers to change, rather than as an input to governmental decision-making. Finally a list of recommendations is put forward as a starting point to reconstruct community-based environmental education. The role considered is one that responds to, and encourages engagement in, debates which expose disparate views, assumptions and positions. Community ideology must be challenged through the public practices of communication and understanding, decision-making, and action. Intervention is not on a level that encourages a preordinate outcome but, rather, what is encouraged is elaborate consideration of disparate views and rational opinions, and the exposure of assumptions and interests behind ideological positions.

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We investigated the home-range size and habitat use of eight Sooty Owls (Tyto tenebricosa tenebricosa) in coastal forests in East Gippsland, Victoria, Australia, between November 2006 and January 2008. The size of home-ranges varied widely; based on 95% adaptive kernel estimates, the average size of home-ranges of males was 3025ha (±1194s.d., n=3), whereas that of females was 994ha (±654s.d., n=5). Sooty Owls utilised a broad range of ecological vegetation classes and topographical features for roosting and foraging at a greater scale than previously assumed. There was minimal selection for habitat types based on floristic composition, primarily only avoiding heathlands (for foraging and roosting) and selecting particular dense foliage (rainforest and riparian scrub) for foliage roosting. Two Owls maintained home-ranges close to logged areas, with logging regrowth (<45 years old) being strongly avoided by both individuals. We recommend that the size of individual reserves for Sooty Owls in commercial forests should be increased to more closely resemble the core spatial resource requirements needed by a pair. Reserves should be largest where they feed predominantly on hollow-dependent prey. Most importantly, rather than conservation measures just focussing on the spatial requirements of Sooty Owls, efforts should be directed towards retaining high densities of crucial resources, such as hollow-bearing trees and mammalian prey species throughout the landscape.

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During my three academic years, I focused on the effects of N fertilization on growth and function of plants and forest stands. The study had the dual objective of estimating the effects of atmospheric N deposition and evaluating the potential management value of N fertilization itself. In particular, the analysis took into account the changes induced in water use and intrinsic transpiration efficiency (ITE), an aspect often overlooked in world literature but of great importance especially in Mediterranean environment, where the positive effects of N fertilization may be denied by the parallel increased transpiration and exacerbated water stress.

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The north-eastern escarpment of Madagascar contains the island’s last remaining large-scale humid forest massifs surrounded by diverse small-scale agricultural mosaics. There is high deforestation mainly caused by shifting cultivation practiced by local land users to produce upland rice for subsistence. Today, large protected areas restrict land users’ access to forests to collect wood and other forest products. Moreover, they are no more able to expand their cultivated land, which leads to shorter shifting cultivation cycles and decreasing plot sizes for irrigated rice and cash crop cultivation. Cash crop production of clove and vanilla is exposed to risks such as extreme inter-annual price fluctuations, pests and cyclones. In the absence of work opportunities, agricultural extension services and micro-finance schemes people are stuck in a poverty trap. New development strategies are needed to mitigate the trade-offs between forest conservation and human well-being. As landscape composition and livelihood strategies vary across the region, these strategies need to be spatially differentiated to avoid implementing generic solutions, which do not fit the local context. However, up to date, little is known about the spatial patterns of shifting cultivation and other land use systems at the regional level. This is mainly due to the high spatial and temporal dynamics inherent to shifting cultivation, which makes it difficult to monitor the dynamics of this land use system with remote sensing methods. Furthermore, knowledge about land users’ livelihood strategies and the risks and opportunities they face stems from very few local case studies. To overcome this challenge, firstly, we used remote sensing data and a landscape mosaic approach to delineate the main landscape types at the regional level. Secondly, we developed a land user typology based on socio-ecological data from household surveys in 45 villages spread throughout the region. Combining the land user typology with the landscape mosaic map allowed us to reveal spatial patterns of the interaction between landscapes and people and to better understand the trade-offs between forest conservation and local wellbeing. While shifting cultivation systems are being transformed into more intensive permanent agricultural systems in many countries around the globe, Madagascar seems to be an exception to this trend. Linking land cover information to human-environmental interactions over large areas is crucial to designing policies and to inform decision making for a more sustainable development of this resource-rich but poverty-prone context.

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1. The often complex architecture of coral reefs forms a diversity of light microhabitats. Analogous to patterns in forest plants, light variation may drive strategies for efficient light utilization and metabolism in corals. 2. We investigated the spatial distribution of light regimes in a spur-and-groove reef environment and examine the photophysiology of the coral Montipora monasteriata (Forskal 1775), a species with a wide habitat distribution. Specifically, we examined the variation in tissue and skeletal thickness, and photosynthetic and metabolic responses among contrasting light microhabitats. 3. Daily irradiances reaching corals in caves and under overhangs were 1-5 and 30-40% of those in open habitats at similar depth (3-5 m), respectively. Daily rates of net photosynthesis of corals in cave habitats approximated zero, suggesting more than two orders of magnitude variation in scope for growth across habitats. 4. Three mechanisms of photoadaptation or acclimation were observed in cave and overhang habitats: (1) a 20-50% thinner tissue layer and 40-60% thinner skeletal plates, maximizing light interception per unit mass; (2) a two- to threefold higher photosynthetic efficiency per unit biomass; and (3) low rates of dark respiration. 5. Specimens from open and cave habitats displayed a high capacity to acclimate to downshifts or upshifts in irradiance, respectively. However, specimens in caves displayed limited acclimation to further irradiance reduction, indicating that these live near their irradiance limit. 6. Analogous to patterns for some plant species in forest gaps, the morphological plasticity and physiological flexibility of M. monasteriata enable it to occupy light habitats that vary by more than two orders of magnitude.