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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.
281

Dynamics of Forest Cover Extent, Forest Fragmentation and Their Drivers in the Lake Victoria Crescent, Uganda From 1989 to 2009

Waiswa, Daniel 29 April 2011 (has links)
Despite the important values forests play in the tropics, sustainable forest management still remains a challenge as manifested through continued forest loss. The objective of this study was to provide information on the dynamics of forest cover and their drivers vital for enhancing sustainable forest management in the Lake Victoria crescent, Uganda. Several methodologies including remote sensing and Geographic Information Systems techniques, analysis of landscape patterns and various social science techniques were integrated in working towards the stated goal. Results showed that the Lake Victoria crescent, Uganda covering an area of about 1,509,228 ha, experienced a decline in forest cover from 9.0% in 1989 to 4.4% in 2009. This was in comparison with non-forest cover which increased from 58.7% in 1989 to 63.5% in 2009 while open water coverage generally remained unchanged averaging 32.3% from 1989 to 2009. Mean annual deforestation rate from 1989 to 2009 decreased with a weighted mean rate of 2.56%. Both deforestation and afforestation declined between 1989 and 2009 although deforestation still exceeded afforestation. In addition to deforestation, the Lake Victoria crescent also experienced forest fragmentation from 1989 to 2009. Forests greater than 100 ha in size were the most vulnerable to forest fragmentation yet they still constituted a big proportion of forest cover in 2009. Deforestation was a consequence of proximate causes which were triggered by a number of underlying drivers acting singly or in combination, with underlying drivers being more influential. In a bid to promote sustainable forest management, there is a need to continue with efforts to curb deforestation and forest fragmentation, especially amongst forests greater than 100 ha. This could be achieved through empowerment of local communities to take a core role in sustainable management of forest resources. / Ph. D.
282

Constructing the problem of "slash-and-burn" agriculture

O'Brien, William Eugene 11 July 2007 (has links)
"Slash-and-burn" agriculture, or shifting cultivation, is perceived by many to be the leading cause of land degradation in tropical forests. Performed mainly by resource-poor farmers, shifting cultivation is the most widespread form of agriculture in the tropics. Concern over its environmental impacts has led to calls throughout the twentieth century for alternatives by policy-makers and development planners. This study employs a constructivist framework, post-colonial perspectives, and rhetorical methods to understand the images which support such assertions regarding shifting cultivation, primarily in policy-oriented depictions. Elements of Kenneth Burke's "dramatistic" method are used, including the analysis of hierarchies which structure discourse, and pentadic analysis. / Ph. D.
283

The Social Cost of Fiscal Federalism and the Depletion of China’s Native Forests

Wang, Haoyu 06 May 2021 (has links)
China's key forested region is located in the northeast. This region consists of state forest enterprises which manage harvesting and reforestation and have represented the most important source of wood supplies since the 1950s. Deforestation is a major problem there, however, and has resulted in several central government reforms. We develop a framework for assessing the social cost of state forest enterprise deforestation. We first develop a two-principal, one-agent model that fits the federalistic organization state forests, in that state forest managers make (potentially hidden) decisions under influence of provincial and central government policies and quotas meant to direct manager behavior. This model is used to derive an expression of the social cost of these hidden actions as well as a comparison of first and second best government policies. We then use panel data from a survey conducted by the Environmental Economics Program in China (EEPC) to compute social welfare losses and use a regression approach to confirm the main factors in these costs in practice. A sensitivity analysis shows that lower harvesting limits and a more accurate monitoring system are the keys to lowering social welfare loss. These are more important than conventional instruments used by the governments such as wages for managers that achieve certain targets. Through regression analysis we find that the remote areas with a higher percentage of mature natural forests are the ones that will always have the highest social welfare loss. These areas are the hardest to monitor, but our results show they must be a critical focus moving forward. / M.S. / China's key forested region is located in the northeast. This region consists of state forest enterprises which manage harvesting and reforestation and have represented the most important source of wood supplies since the 1950s. Deforestation is a major problem there. We develop a framework for assessing the damage to the society because of deforestation. We develop a theoretical model to describe the forest management structure, in which state forest managers make (potentially hidden) decisions under influence of provincial and central government policies. This model is used to derive an expression of the damage. We then use data from a survey conducted by the Environmental Economics Program in China (EEPC) to compute the damage and confirm the main factors in these damages in practice. We find that lower harvesting limits and a more accurate monitoring system are the keys to lowering the damage. These are more important than conventional instruments used by the governments such as wages for managers that achieve certain targets. We also find that the remote areas with a higher percentage of mature natural forests are the ones that will always have the largest damage. These areas are the hardest to monitor, but our results show they must be a critical focus moving forward.
284

A multiscale analysis and quantification of human impacts on Sumatran tiger (Panthera tigris sumatrae) habitat in Riau, Sumatra

Poor, Erin Elizabeth 25 September 2018 (has links)
Worldwide, we are losing biodiversity at unprecedented rates, and due to deforestation, degradation and poaching, Southeast Asian wildlife is facing extreme threats. Indonesia recently eclipsed Brazil in having the world's highest deforestation rate, largely due to the rise of the palm oil industry. Indonesia contains multiple biodiversity hotspots and endangered species such as the Sumatran tiger (Panthera tigris sumatrae). While Riau Province, Sumatra, produces approximately 20% of the world's palm oil, tigers still inhabit parts of Riau, though their habitat and prey are understudied. Thus, in this research, I aim to assess and quantify how tiger habitat has changed, how it will continue to change, and provide recommendations on how to improve the landscape for tigers. I create the first accuracy-assessed land cover maps of Riau, and then predict land cover change from 2016 – 2050. Using this newly created land cover map, I assess whether Tesso Nilo National Park, Bukit Tigapuluh National Park, and Rimbang Baling Wildlife Reserve are effective at preventing deforestation. Next, I examine human impacts within Tesso Nilo specifically, due to its suitability for oil palm and its potential as a stepping stone for wildlife movement from the western, mountains to the eastern peatlands of Sumatra. Finally, I examine impacts of human presence within Rimbang Baling on felid-prey relationships. I predict that by 2050, over 60% of natural forest in Riau will be lost, and all protected areas only confer low levels of protection. I determined that Tesso Nilo National Park has nearly 2500 km of roads within it and no areas within the park are untouched by humans. Wildlife detections were low near the boundary of Rimbang Baling and there was evidence of humans negatively impacting mousedeer (Tragulus spp) behavior. I suggest focusing on securing the habitat within Rimbang Baling and Bukit Tigapuluh to ensure habitat for dispersing tigers from the western mountains, in addition to, and perhaps before focusing on restoring Tesso Nilo and creating wildlife corridors. While tiger recovery in Riau will be difficult, with education, dedication, persistence and intelligent planning, tigers may be able to persist in this unique ecosystem in the long-term. / Ph. D. / Worldwide, we are losing plants and animals at unprecedented rates, and due to deforestation, degradation and poaching, Southeast Asian wildlife is facing extreme threats. Indonesia recently passed Brazil in having the world’s highest deforestation rate, largely due to the rise of the palm oil industry. Indonesia has a wide diversity of plants and animals, including endangered species such as the Sumatran tiger. While Riau Province, Sumatra, produces approximately 20% of the world’s palm oil, tigers still inhabit parts of Riau, though their habitat and prey are understudied. Thus, in this research, I aim to assess how tiger habitat has changed, how it will continue to change, and provide recommendations to improve the landscape for tigers. I create the first land cover maps of Riau that have been verified with field data, and then predict land cover change from 2016 – 2050. Using this land cover map, I assess whether Tesso Nilo National Park, Bukit Tigapuluh National Park, and Rimbang Baling Wildlife Reserve are effective at preventing deforestation. Next, I examine human impacts within Tesso Nilo, due to its soil characteristics making it suitable for oil palm and its potential as habitat for wildlife movement from the western, mountains to the eastern swamps of Sumatra. Finally, I examine impacts of humans within Rimbang Baling on wild cat-prey relationships. I predict that by 2050, over 60% of forest in Riau will be lost, and all protected areas only provide slight protection. I determined that Tesso Nilo has nearly 2500 km of roads within it and no areas within the park are untouched by humans. Wildlife sightings were low near the boundary of Rimbang Baling and there was evidence of humans negatively impacting tiger prey behavior. I suggest focusing on securing the forests within Rimbang Baling and Bukit Tigapuluh to ensure forest for tigers that may come from the western mountains, in addition to, and before focusing on restoring Tesso Nilo and creating wildlife movement areas. While tiger recovery in Riau will be difficult, with education, dedication, persistence and intelligent planning, tigers may be able to persist in this unique ecosystem in the long-term.
285

Deforestation, degradation, and natural disturbance in the Amazon: using a new monitoring approach to estimate area and carbon loss

Bullock, Eric L. 10 February 2020 (has links)
Forest degradation causes environmental damage and carbon emissions, but its extent and magnitude are not well understood. New methods for monitoring forest degradation and deforestation show that more disturbance has occurred in the Amazon in recent decades than previously realized, indicating an unaccounted for source of carbon emissions and damage to Amazon ecosystems. Forest degradation and natural disturbance change a landscape, but the visible damage apparent in satellite images may be temporary and difficult to differentiate from undisturbed forests. Time series analysis of Landsat data used in a spectral mixture analysis improves monitoring of forest degradation and natural disturbance. In addition, the use of statistical inference accounts for classification bias and provides an estimate of uncertainty. Application of the methodology developed in this dissertation to the Amazon Ecoregion found that forest degradation and natural disturbance were more prevalent than deforestation from 1995 to 2017. Of consequence, the total area of forest in the Amazon that has been recently disturbed is greater than previously known. Overall, deforestation affected 327,900 km2 (±15,500) of previously undisturbed forest in the Amazon while degradation and natural disturbance affected 434,500 km2 (±22,100). Forest degradation and natural disturbance occur more frequently during drought years, which have increased in frequency and severity in recent years. Deforestation has largely decreased since 2004, while forest degradation and natural disturbance have remained consistent. Previously disturbed forests are lower in biomass than undisturbed forests, yet regeneration after disturbance gradually sequesters carbon. A carbon flux model shows that gross aboveground carbon loss from forest degradation and natural disturbance and deforestation from 1996 to 2017 in the Amazon were 2.2-2.8 Pg C and 3.3-4.3 Pg C, respectively. Since 2008, however, carbon loss from degradation and natural disturbance has been approximately the same as from deforestation. The methodologies developed in this dissertation are useful for monitoring deforestation and degradation throughout the world’s forest ecosystems. By leveraging dense data time series, statistical inference, and carbon modeling it is possible to quantify areas of deforestation and forest degradation in addition to the resulting carbon emissions. The results of this dissertation stress the importance of degradation and natural disturbance in the global carbon cycle and information valuable for climate science and conservation initiatives.
286

A Reserva Legal, sua instituição e o seu desmatamento em propriedades rurais do município de Sorriso, Mato Grosso / The Legal Reserve, its institution and its deforestation in rural properties of Sorriso, State of Mato Grosso.

Castro, Daniel Stella 12 August 2010 (has links)
Este estudo busca propor uma análise do fenômeno de desmatamento ilegal da Reserva Legal, objetivando compreender os fatores que condicionaram o baixo enforcement exercido pelo Estado acerca do cumprimento das regras de conservação da Reserva Legal instituídas pela Lei nº 4.771 de 15 de setembro de 1965 e suas alterações (Código Florestal). Para tanto, foi necessário conhecer o estado da arte dos trabalhos científicos que abordam assuntos relacionados ao desmatamento ilegal da Reserva Legal, enfatizando pesquisas realizadas na Amazônia Legal, em particular no Estado de Mato Grosso, e ao mesmo tempo entender o ambiente institucional de criação e construção das regras de conservação da vegetação nativa dentro da propriedade rural, sobretudo a Lei 4.771 de 15 de setembro de 1965 (Código Florestal). Sendo assim, assumindo a análise da relação do Estado com a sociedade como um fator crucial ao entendimento da pergunta central do trabalho, apropriou-se de alguns conceitos da Teoria do Estado capitalista de Nicos Poulantzas, como modo de produção, classe social e poder, sob a ótica que o Estado não é sujeito tão pouco coisa ou objeto de uma determinada classe ou frações de classe, mas sim a condensação das contradições existentes entre as diversas práticas de classe numa formação social, permitindo a manutenção ou subversão da unidade desta formação. Neste sentido, optou-se por uma primeira aproximação acerca da formação econômico-social do Estado de Mato Grosso, pois diversas propriedades rurais localizadas nesta porção do território brasileiro ainda apresentam o mesmo proprietário que realizara a retirada da vegetação nativa para o estabelecimento do monocultivo. Com efeito, buscando uma contextualização do estudo em questão em virtude de evidências empíricas de áreas de Reserva Legal inferiores ao limite mínimo exigido em lei, optou-se pela análise de propriedades rurais localizadas no município de Sorriso, Mato Grosso. Todas as propriedades rurais dos sojicutores entrevistados que realizaram o desmatamento até 1995 apresentaram passivo ambiental em relação à Reserva Legal. Assim, justifica-se o reduzido enforcement do Estado em relação ao cumprimento da regra acerca da Reserva Legal no município de Sorriso, ao período do início da colonização privada da década de 1970 até a primeira metade da década de 1990, pela permanência dos interesses da classe latifundiária e dos grandes produtores no poder do Estado. Desta maneira, não fazia parte no horizonte dos seus interesses dentro de sua prática de classe, permitir que sua principal atividade fosse obliterada pelas regras de conservação da Reserva Legal. Importante lembrar que no Estado de Mato Grosso, os interesses ambientalistas passaram a ter força social e ser representados como classe lutando pelos seus interesses no seio do poder do Estado, a partir da década de 1990. / This study expects to set an analysis about the illegal deforestation phenomenum of the Legal Reserve in many brazilian rural properties in order to clarify the driven factors of the lack State enforcement related to formal rules conservation of natural cover vegetation inside rural propertires instituted by the federal law 4.771, September 15, 1965 (Brazilian Forest Code). Thus it was necessary to access the actual state of the art in scientific research related to the illegal deforestation of Legal Reserve, aiming scientific studies developed in the Legal Amazon, in particular in the State of Mato Grosso. At the same time, it was needed to understand the institutional environment related to the creation of natural vegetation conservation rules for rural properties, in particular the institution of the Brazilian Forest Code. Assuming the analysis of the State and society relation as a key factor to solve the main question of this dissertation, a theoretical framework proposed by Nicos Poulantzas to explain the Capitalist State was chosen. In fact some key concepts based on his theory, such as social class, power and means of production were aplied in a case study (rural properties from Sorriso, State of Mato Grosso) structured on his proposal that the State does not mean the subject or the object of some specific class, but the contradictions consolidation from the class conflicts in a social formation. The State of Mato Grosso was chosen as a result of many rural properties there still have the same owner which provided the deforestation of natural cover vegetation. This fact was empirically observed in some rural properties of Sorriso, where levels of Legal Reserve conservation were below than permitted by the Brazilian Forest Code. Nevertheless, in order to give a scientific basis to the case study, an analysis of the economic and social formation of the State of Mato Grosso was constructed. The levels of Legal Reserve in all rural properties analised were bellow than the legal limities related to the Forest Code. Then, the lack State enforcement of formal rules related to conservation of natural cover vegetation inside rural propertires for the analised period can be explained by the continue presence in the State power of the landlord class and big farm producers interests. Based on the last observation, the class strugle in the State power would not aloud to have it´s mains activity constrained by the conservation rules of the Forest Code. It´s important to remember that environmental interests became to have a class representation in the State of Mato Grosso in the early nineties decade.
287

A Reserva Legal, sua instituição e o seu desmatamento em propriedades rurais do município de Sorriso, Mato Grosso / The Legal Reserve, its institution and its deforestation in rural properties of Sorriso, State of Mato Grosso.

Daniel Stella Castro 12 August 2010 (has links)
Este estudo busca propor uma análise do fenômeno de desmatamento ilegal da Reserva Legal, objetivando compreender os fatores que condicionaram o baixo enforcement exercido pelo Estado acerca do cumprimento das regras de conservação da Reserva Legal instituídas pela Lei nº 4.771 de 15 de setembro de 1965 e suas alterações (Código Florestal). Para tanto, foi necessário conhecer o estado da arte dos trabalhos científicos que abordam assuntos relacionados ao desmatamento ilegal da Reserva Legal, enfatizando pesquisas realizadas na Amazônia Legal, em particular no Estado de Mato Grosso, e ao mesmo tempo entender o ambiente institucional de criação e construção das regras de conservação da vegetação nativa dentro da propriedade rural, sobretudo a Lei 4.771 de 15 de setembro de 1965 (Código Florestal). Sendo assim, assumindo a análise da relação do Estado com a sociedade como um fator crucial ao entendimento da pergunta central do trabalho, apropriou-se de alguns conceitos da Teoria do Estado capitalista de Nicos Poulantzas, como modo de produção, classe social e poder, sob a ótica que o Estado não é sujeito tão pouco coisa ou objeto de uma determinada classe ou frações de classe, mas sim a condensação das contradições existentes entre as diversas práticas de classe numa formação social, permitindo a manutenção ou subversão da unidade desta formação. Neste sentido, optou-se por uma primeira aproximação acerca da formação econômico-social do Estado de Mato Grosso, pois diversas propriedades rurais localizadas nesta porção do território brasileiro ainda apresentam o mesmo proprietário que realizara a retirada da vegetação nativa para o estabelecimento do monocultivo. Com efeito, buscando uma contextualização do estudo em questão em virtude de evidências empíricas de áreas de Reserva Legal inferiores ao limite mínimo exigido em lei, optou-se pela análise de propriedades rurais localizadas no município de Sorriso, Mato Grosso. Todas as propriedades rurais dos sojicutores entrevistados que realizaram o desmatamento até 1995 apresentaram passivo ambiental em relação à Reserva Legal. Assim, justifica-se o reduzido enforcement do Estado em relação ao cumprimento da regra acerca da Reserva Legal no município de Sorriso, ao período do início da colonização privada da década de 1970 até a primeira metade da década de 1990, pela permanência dos interesses da classe latifundiária e dos grandes produtores no poder do Estado. Desta maneira, não fazia parte no horizonte dos seus interesses dentro de sua prática de classe, permitir que sua principal atividade fosse obliterada pelas regras de conservação da Reserva Legal. Importante lembrar que no Estado de Mato Grosso, os interesses ambientalistas passaram a ter força social e ser representados como classe lutando pelos seus interesses no seio do poder do Estado, a partir da década de 1990. / This study expects to set an analysis about the illegal deforestation phenomenum of the Legal Reserve in many brazilian rural properties in order to clarify the driven factors of the lack State enforcement related to formal rules conservation of natural cover vegetation inside rural propertires instituted by the federal law 4.771, September 15, 1965 (Brazilian Forest Code). Thus it was necessary to access the actual state of the art in scientific research related to the illegal deforestation of Legal Reserve, aiming scientific studies developed in the Legal Amazon, in particular in the State of Mato Grosso. At the same time, it was needed to understand the institutional environment related to the creation of natural vegetation conservation rules for rural properties, in particular the institution of the Brazilian Forest Code. Assuming the analysis of the State and society relation as a key factor to solve the main question of this dissertation, a theoretical framework proposed by Nicos Poulantzas to explain the Capitalist State was chosen. In fact some key concepts based on his theory, such as social class, power and means of production were aplied in a case study (rural properties from Sorriso, State of Mato Grosso) structured on his proposal that the State does not mean the subject or the object of some specific class, but the contradictions consolidation from the class conflicts in a social formation. The State of Mato Grosso was chosen as a result of many rural properties there still have the same owner which provided the deforestation of natural cover vegetation. This fact was empirically observed in some rural properties of Sorriso, where levels of Legal Reserve conservation were below than permitted by the Brazilian Forest Code. Nevertheless, in order to give a scientific basis to the case study, an analysis of the economic and social formation of the State of Mato Grosso was constructed. The levels of Legal Reserve in all rural properties analised were bellow than the legal limities related to the Forest Code. Then, the lack State enforcement of formal rules related to conservation of natural cover vegetation inside rural propertires for the analised period can be explained by the continue presence in the State power of the landlord class and big farm producers interests. Based on the last observation, the class strugle in the State power would not aloud to have it´s mains activity constrained by the conservation rules of the Forest Code. It´s important to remember that environmental interests became to have a class representation in the State of Mato Grosso in the early nineties decade.
288

The Role of the Forest in Climate Policy

Eriksson, Mathilda January 2016 (has links)
Abstract In Paper [I], I develop the FOR-DICE model to analyze optimal global forest carbon management. The FOR-DICE is a simple framework for assessing the role of the boreal, tropical, and temperate forests as both a source of renewable energy and a resource to sequester and store carbon. I find that forests play an important role in reducing global emissions, especially under ambitious climate targets. At the global level, efforts should focus on increasing the stock of forest biomass rather than increasing the use of the forest for bioenergy production. The results also highlight the important role of reducing tropical deforestation to reduce climate change. In Paper [II], I develop the FRICE to investigate the role of two key efforts to increase the stock of forest biomass, namely, afforestation and avoided deforestation. FRICE is a multi-regional integrated assessment model that captures the dynamics of forest carbon sequestration in a transparent way and allows me to investigate the allocation of these actions across space and time. I find that global climate policy can benefit considerably from afforestation and avoided deforestation in tropical regions, and in particular in Africa. Avoided deforestation is particularly effective in the short run while afforestation provides the largest emissions reductions in the medium run. This paper also highlights the importance of not solely relying on avoided deforestation as its capacity to reduce emissions is more limited than afforestation, especially under more stringent temperature targets. In Paper [III], we investigate how uncertainties linked to the forest affect the optimal climate policy. We incorporate parameter uncertainty on the intrinsic growth rate and climate effects on the forest by using the state-contingent approach. Our results show that forest uncertainty matters. We find that the importance of including forest in climate policy increases when the forest is subject to uncertainty. This occurs because optimal forest response allows us to reduce the costs associated with uncertainty. In Paper [IV], we explore the implications of asymmetries in climate policy arising from not recognizing forest carbon emissions and sequestration in the decision-making process. We show that not fully including carbon values associated with the forest will have large effects on different forest controls and lead to an increase in emissions, higher carbon prices, and lower welfare.  We further find, by investigating the relative importance of forest emissions compared to sequestration, that recognizing forest emissions from bioenergy and deforestation is especially important for climate policy.
289

Realising REDD in Africa : risk, feasibility and supporting policy

Knowles, Tony 12 1900 (has links)
Thesis (PhD)--Stellenbosch University, 2012. / ENGLISH ABSTRACT: Responding appropriately to anthropogenic climate change presents a considerable challenge to humankind. Projected changes in climate are anticipated to affect the world's natural systems, human health and economies in many ways. Consequently, there is an urgent need to implement climate change mitigation and adaptation measures that are appropriate and efficient. This dissertation focuses on aspects of risk and feasibility associated with land use based climate change mitigation. First, it reviews policy, implementation and incentive issues that are key to promoting permanence and reducing the risk of leakage associated with reducing emissions from deforestation and forest deforestation (REDD1) in sub-Saharan Africa. Secondly, it assesses the transaction costs associated with the implementation of avoided deforestation and reforestation activities and their effect on the financial feasibility of ventures located in woodland and rangeland systems. Thirdly, it explores the potential impact of biophysical risk factors (such as fire) on the outcome of REDD activities in two chapters. The first risk chapter introduces the notion of biophysical risk and reviews the risk of fire to REDD activities located in important African vegetation types. The second chapter on risk uses the Century Ecosystem Program and published climate projection data to assess the effect of projected changes in temperature, rainfall and atmospheric carbon dioxide on the outcome of REDD activities. The results indicate that, among the biophysical risk variables assessed, fire may not present a major risk to REDD activities located in African woodland, savanna and grassland systems. In contrast, fire may present a significant risk in moist forests where unprecedented dry periods may allow fire to occur in a system where it has previously been absent. The analysis of the affect of climate change found that changes in climate are generally predicted to lead to an increase in carbon stocks and sequestration rates for the vegetation types assessed. Exceptions do occur, such as the modeled effect on nutrient-rich savannas, which require further investigation. The analysis of transaction costs associated with REDD activities illustrated that such costs may inhibit the feasibility of smaller-scale activities, especially in ecosystems outside of moist forests with relatively low carbon stocks and associated revenues. Whereas the proposed creation of national-scale capacity may reduce some transaction costs to a certain extent, there is a clear need to better understand the true cost of REDD activities. In terms of required supporting policy and implementation capacity, it is noted 1) that multi-criteria land use planning is particularly important in reducing permanence risk, 2) that the scope of recognized land use activities that reduce atmospheric GHG needs to be expanded if the benefits of REDD are to be fully realised and 3) that informal land tenure may not require transformation prior to successful, sustainable implementation. A review of the appropriateness of community-based forest carbon monitoring found that such an approach presents significant cost savings while providing local employment and incentive opportunities. Exposure to such initiatives to date indicated that the quality of data collected is adequate and sufficiently robust to fulfill project and national-scale reporting and verification requirements. / AFRIKAANSE OPSOMMING: Antropogeniese klimaatsverandering hou daadwerklike uitdagings vir die mensdom in. Huidige voorspellings dui daarop dat klimaatsverandering natuurlike sisteme, gesondheid en die ekonomie op 'n verskeidenheid van vlakke gaan beinvloed. Daar is dus 'n dringende nood aan korrekte en effektiewe aanpassings- en mitigasie maatstawwe wat geimplementeer kan word. Hierdie proefskrif fokus op die risiko en lewensvatbaarheid van grondgebruiksgebaseerde klimaatsverandering mitigasie. Eerstens gee dit 'n oorsig van die beleids en implementasie dryfvere wat noodsaaklik is vir die bevordering van permanentheid en die verlaging van die risiko van lekkasie wat geassosieer word met verlaagde emissies vanwee degradasie en ontbossing (VEDO2) in sub-Sahara Afrika. Tweedens analiseer dit die transaksiekoste wat geassosieer word met die vermyding van ontbossing en herbebossing en die effek daarvan op die finansiele lewensvatbaarheid van sulke aktiwiteite in bosveld en weiveld. Derdens ondersoek die proefskrif die biofisiese risiko faktore (soos vuur) op die uitslag van VEDO aktiwiteite in twee hoofstukke. Die eerste hoofstuk word ingelei deur 'n ontleding en verklaring van biofisiese risiko en gee dan 'n oorsig oor die risiko van vuur op VEDO projekte in belangrike plantegroei-tipes in Afrika. Die tweede hoofstuk maak gebruik van die Century Ekostelsel Program om die impak van voorspelde veranderings in temperatuur, reenval en atmosferiese koolstofdioksied op VEDO aktiwiteite te evalueer. Die resultate dui aan dat onder die biofisiese risiko faktore wat ondersoek is, vuur nie so „n belangrike risiko inhou vir VEDO projekte in die bosveld, savanna en grasveld plantegroeitipes in Afrika nie. In teenstelling hou vuur 'n groot risiko in vir nat woude waar ongekende droeë tydperke kan veroorsaak dat vuur wel mag voorkom in „n stelsel waar dit voorheen afwesig was. Die analise op die effek van klimaatsverandering het bevind dat veranderinge in klimaat tipies sal lei tot a toename in koolstof voorrade en verhoogde sekwestrasie tempos vir die plantegroeitipes wat geevalueer is. Daar was egter uitsonderings, soos byvoorbeeld die gemodeleerde impakte op nutrientryke savannas wat verdere ondersoek benodig. Die analise ten opsigte van die transaksiekoste wat gepaardgaan met VEDO aktiwiteite illustreer dat sulke kostes dalk die lewensvatbaarheid van kleinerskaal projekte mag benadeel, veral in ekostelsels anders as nat woude met relatief lae koolstof voorrade en geassosieerde inkomste. Die voorgestelde skepping van kapasiteit op 'n nasionale vlak mag dalk transaksie koste verlaag tot 'n mate, maar daar is duidelik 'n behoefte om beter insigte te verkry oor die ware kostes van VEDO aktiwiteite. Wat betref die vereiste ondersteunende beleid en implimentasie kapasiteit is daar bevind dat 1) multi-kriteria grondgebruik beplanning uiters belangrik is in die verlaging van permanentheidsrisiko, 2) die omvang van erkende grondgebruiks aktiwiteite moet uitgebrei word om ten volle voordeel te trek uit VEDO, 3) dat informele grondbesit dalk nie transformasie vereis voor suksesvolle, volhoubare implementasie nie. „n Oorsig oor die aanvaarbaarheid van gemeenskapsgebaseerde woudkoolstofmonitering het gevind dat so 'n benadering tot groot kostebesparings lei terwyl dit ook plaaslike werkskepping bevorder en dien as dryfveer vir projekte. Blootstelling aan sulke inisiatiewe tot op hede dui aan dat die kwaliteit van die data wat ingesamel is voldoen aan projek- sowel as nasionale vlak verslaggewingsvereistes.
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Changes in eco-hydrological functioning after tropical rainforest transformation to rubber and oil palm plantations

Röll, Alexander 30 September 2015 (has links)
No description available.

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