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Global change is substantially led by greenhouse gases (GHG) emissions (Ruddiman, 2013). In Brazil, the largest emission rates come from the forestry & land-use change sector, which historically accounts for more than half of Brazil’s emissions (SEEG, 2016a). Within the Legal Amazon, deforestation is the main driver of land-use change (TerraClass, 2014). Furthermore, Amazon-based settlements, established by Brazil’s Land Reform, play an important role in this process, as 28.6% of all Amazon deforestation stemmed from this type of land property in 2016 alone (Azevedo et al, 2016). Even though public policies aim at curbing this source of land-clearing, they often fail to achieve this goal. Hence, this thesis will analyse why policies do not efficiently prevent clear-cutting in Amazon-based settlements. This analysis is done through a multilevel comparison between political priorities and local perceptions on deforestation. The inquiry relies on text analysis to assess the Land Reform as a land-use policy and the Forest Code as a deforestation policy. It further summarizes the impressions of local family farmers collected in the fieldwork. Then it compares both results to understand why policies fail to fully curb deforestation. The main conclusion is that policies fail because they are erratic, they do not sufficiently take into account the social aspects of deforestation and they do not promote resilience in local communities. The geographical scope of the case-study is western Pará state, in which 30.8% of all deforestation occur in Amazon-based settlements (Ibidem). It is in Pará where the case-study takes place, namely the PAS Project carried out by the Amazon Environmental Research Institute. The main contribution of this thesis is to adopt a socio-ecological systems approach to compare policy priorities to local case-study results and to emphasize the interlinkages between income-generation and land-clearing.

Deforestation and land use change are widespread in western Uganda. However, the spatial patterns and time-series of change and the reasons why it is occurring remain to be fully investigated. In this work a combination of satellite imagery and social surveys is used to quantify forest gains and loss over the last three decades in the region close to Lake Albert, whilst also providing an account of possible drivers of change. This area proves to be interesting as it covers regions with both formally protected areas (gazetted regions) and un-protected forest, the latter being largely under private ownership. Remote sensing data from the Landsat satellites were gathered for forest change detection, and were processed using standard remote sensing techniques, then quantified using GIS and regression methods. Fieldwork allowed these data to be ground truthed while gathering (quantitative) household surveys and (qualitative) key informant interviews. Quantitative surveys were analysed using Principal Components Analysis (PCA) and cluster analysis, and were compared qualitatively with the satellite analysis and stakeholder interviews. The results show that forest cover declined significantly outside gazetted areas at the expense of varying local?scale processes, although the protection of the gazetted forests was remarkably successful. In forest corridors outside gazetted regions, losses exceeded 90% (p<0.05). Survey data suggest that rural poor households were more likely to be situated in forested regions, and were more dependent on forest resources for their livelihoods. However, the drivers of change were spatially variable, with expansion of sugarcane farming being a likely driver in the northern areas, but small?scale agricultural expansion a significant factor in the more southern parts of the study region. While there is wide agreement within the data that the patterns of forest cover and land use changes are anthropogenically driven, more specific drivers are swamped by intricacies of the bio-physical and socio-economic preconditions that are inseparable in both space and time, although agricultural expansion and population growth were evident and pervasive. The analyses provide insights into complex anthropogenic processes at various spatial scales, and policy recommendations provided are widely applicable for developing countries struggling to conserve nature whilst boosting economic growth.

Este artículo explica la forma como las estrategias productivas familiares de los colonos agricultores y las percepciones que los agricultores tienen sobre el bosque influyen en el ritmo de deforestación. Este tipo de enfoque, basado en el análisis de procesos endógenos, procura contextualizar y entender cómo los agricultores funcionan dentro de un contexto de «transición forestal», resultado de significativos cambios económicos, expansión del mercado y desarrollo de la infraestructura vial. Nuestro argumento central es que las indicadas estrategias de los agricultores en el cantón de Tena, en relación con el ritmo de deforestación en sus fincas, se construyen como resultado de la combinación de un conjunto de procesos económicos de sobrevivencia a corto y mediano plazo y desde los cuales se elaboran percepciones mentales o culturales sobre el bosque. Tales procesos endógenos no son únicamente respuestas a contextos externos sino que también se derivan de ciclos demográficos y dinámicas de acumulación que ocurren dentro de las familias de los productores. / This article explains how the family productive strategies of farmer settlers and their perceptions of the forest influence the rate of deforestation. This particular approach, based on the analysis of endogenous processes, seeks to contextualize and understand how farmers operate within a context of «forest transition», as a result of significant economic changes, market expansion and road infrastructuredevelopment. Our central argument is that the farmers’ strategies in Tena, in relation to the rate of deforestation on their farms, are a result of the combination of a set of economic processes of survival in the short and medium term and of their mental or cultural perceptions of the forest. Such endogenous processes arenot only responses to external contexts but are also derived from demographic cycles and accumulation dynamics that occur within the families of producers.

A Tese trata da ação pública voltada à governança socioambiental da Amazônia na década de 2000. Os objetivos da pesquisa foram registrar o conjunto de ações implementadas e analisar os principais elementos que explicam os resultados do sucesso obtido na inédita redução do desmatamento verificada no período, que se caracterizou pela consistência e constância. A metodologia adotada consistiu na identificação e classificação das iniciativas desenvolvidas nos campos institucional, legal e político pelo Plano de Prevenção e Controle do Desmatamento na Amazônia (PPCDAm); avaliação do esforço governamental empreendido de forma comparativa com as iniciativas da década anterior; suas correlações com as taxas de desmatamento; o grau de impacto nas mídias nacional e regional das medidas implementadas; e a percepção de atores locais sobre os principais fatores que explicam a redução obtida no desmatamento. Para o desenvolvimento da pesquisa foi realizada extensa revisão bibliográfica; analisados dados secundários das principais instituições de pesquisa e de produção de estatísticas socioeconômicas sobre a região; feito levantamento detalhado dos atos legais e infralegais elaborados e das ações implementadas pelo governo federal na região no período de 1990 a 2010; levantamento pormenorizado das matérias sobre desmatamento na Amazônia veiculadas pelos principais veículos de imprensa, em âmbito nacional e regional do período de 1990 a 2010; produção de dados primários, notadamente por meio da utilização de sistema de informação geográfica, que permitem o cruzamento e espacialização de informações secundárias; e realizada pesquisa semiestruturada com atores locais. Os resultados indicam que, associadas ao efeito direto das ações desenvolvidas, muitas das quais tiveram baixa implementação, o volume expressivo de ações de fiscalização e ordenamento territorial, principalmente com a criação de unidades de conservação em terras públicas nas zonas de expansão da fronteira agrícola e no aperfeiçoamento do monitoramento por satélite, somadas à grande repercussão das operações lideradas pela Polícia Federal e a presença do governo federal de forma articulada e constante, estabeleceu na sociedade local uma percepção acentuada de aumento do risco, que induziu a uma mudança de comportamento em relação ao cumprimento da legislação ambiental. A conclusão gera elementos para uma discussão sobre a importância da coerência de posicionamento do Estado e sua clara comunicação à sociedade, constância de atuação e rigor na exigência do cumprimento das normas legais para, juntamente com medidas objetivas de ação pública, na indução da governança socioambiental com efetividade e eficácia. As mudanças no posicionamento do governo federal frente ao tema observadas nos últimos cinco anos e a estabilização da curva descendente da taxa de desmatamento observada a partir de 2012 juntamente com o recente aumento registrado nos anos 2014 e 2015, reforçam os argumentos para a oportunidade dessa discussão. / The thesis deals with public action focused on the socio-environmental governance of the Amazon in the decade of 2000. The goals of the research were to record the set of actions implemented and to analyze the main elements that explain the results of the success obtained in the unprecedented reduction of deforestation in the period, characterized by consistency and constancy. The methodology adopted consisted in identifying and classifying the initiatives developed in the institutional, legal and political fields by the Plan for Prevention and Control of Deforestation in the Amazon (PPCDAm, in Portuguese acronym); evaluation of the governmental effort undertaken in a comparative manner with the initiatives of the previous decade; their correlations with deforestation rates; the impact of the implemented measures on national and regional media; and perception of local actors about the main factors that explain the achieved reduction in deforestation. For the development of the research, an extensive bibliographic review was carried out; secondary data from the main research institutions and socioeconomic statistics on the region were analyzed; a detailed survey of the legal and regulatory acts and the actions implemented by the federal government in the region in the period from 1990 to 2010 was produced; a detailed survey of the press material about Amazon deforestation carried out by the main media outlets at national and regional levels from 1990 to 2010 was developed; production of primary data, notably through the use of geographic information system, thus allowing secondary information intersection and spatialization; and a semi-structured research with local actors was undertaken. The results indicate that, associated with the direct effect of the developed actions, many of which had low implementation, the expressive number of actions on territorial control and planning, mainly with the creation of conservation units on public lands in the agricultural frontier zones and the improvement of satellite monitoring, along with the great repercussion of operations led by the Federal Police and the presence of the federal government in an articulated and constant manner, established among local society a remarkable perception of risk increase, which induced a change of behavior in relation to their compliance with environmental legislation. The conclusion creates elements for a discussion about the importance of the coherence in the State\'s position and its clear communication to the society, constancy of action and rigor in the requirement of compliance with the legal norms, together with objective measures of public action, in the induction of an effective and efficiency socio-environmental governance. The changes in the federal government\'s position in the last five years and the stabilization of the downward trend in the rate of deforestation observed from 2012, as well as the recent increase in 2014 and 2015, reinforce the arguments for the opportunity of this discussion.

Various biotic and abiotic agents are changing forests. Prolonged human activities substantially could cause not only different changes in forests but also could accelerate natural hazards in the Anthropocene. Despite several remote sensing-based research in forest changes, there is a need for a holistic study that could visualize different dimensions of anthropogenic-induced forest changes such as forest loss, forest fragmentation, and forest degradation. Besides, the effects of these changes require to be investigated in the natural hazards’ studies in forest regions. This research was accomplished for holistic assessing of long-term forest loss, forest fragmentation, and forest degradation induced by human activities such as sprawling residential areas and expanding road networks in northeast Iran. Moreover, it has investigated the significance of forest dynamics in analyzing of landslide susceptibility in the forest regions. The time series of Landsat data with the contribution of aerial photos were employed to investigate long-term forest changes in three spans from 1966 to 2016. The expansion of forest roads was extracted from a combination of satellite images and topographic maps. Both pixel– and object-based approaches were used for analyzing forest changes. The spatial autocorrelation indicators and spatial regression models were applied for visualizing patterns of forest changes and possible relationships between forest changes and the expansion of residential areas and road networks. Furthermore, the detection of old and new landslide events was accomplished through Sentinel-1 and -2 images and DEM derivatives using object-oriented random forest method. The significance of conditioning and triggering factors that control the susceptibility of protected and non-protected forests to landslides was explored using the object-based random forest approach as well. Key findings revealed that the expansion of residential areas and rural roads have increasingly heightened the rates of forest loss before 2000. However, the spatial patterns of forest dynamics were changed from forest loss to forest fragmentation and forest degradation– along with the expansion of forest and mine roads– since the 1980s. Although the topographic and hydrologic features were the top influential predictors that control the susceptibility of protected forests to landslides, the natural and anthropogenic triggers have obtained significant values in non-protected forests to the landslides as well; forest fragmentation and logging were the top features of anthropogenic triggers. This research verifies that influential variables are different either for detecting landslides or for assessing landslide susceptibility in different forest regions. The spatial-based regression models showed higher efficiency than the traditional regression model for modelling relationships between forest changes and anthropogenic- induced drivers; however, there was no priority between spatial models. Random forest algorithm demonstrated satisfactory accuracy for mapping of both old and new landslides and landslide susceptibility with higher accuracy in the protected forests. This research has investigated human-induced forest changes; however, other abiotic and biotic agents may cause these changes such as climate hazards, forest fires, insect outbreaks, pathogens, and other natural hazards that need to be explored in the future studies. / Verschiedene biotische und abiotische Faktoren verursachen Veränderungen im Wald. Dauerhafte menschliche Eingriffe im Anthropozän könnten nicht nur zu unterschiedlichen Typen von Veränderungen im Wald selbst führen, sondern auch bestehende Naturgefahren verstärken. Trotz verschiedener fernerkundungsgestützter Forschungsarbeiten zu Waldveränderungen besteht Bedarf an einer holistischen Studie, welche verschiedene Dimensionen anthropogen verursachter Waldveränderungen wie Waldverlust, Waldfragmentierung und Waldschädigung aufzeigen kann. Außerdem ist es notwendig, die Auswirkungen derartiger Veränderungen in Naturgefahrenstudien für Waldgebiete zu untersuchen. Ziel dieser Forschung war es, eine holistische Bewertung von langfristigem Waldverlust, Waldfragmentierung und Waldschädigung durchzuführen, die durch menschliche Aktivitäten wie Ausbreitung von Siedlungsgebieten und Ausbau von Straßennetzen im Nordosten des Iran verursacht werden. Darüber hinaus hat diese Forschungsarbeit die Bedeutung der Walddynamik in der Analyse von Rutschungsneigung innerhalb von Waldgebieten untersucht. Um langfristige Waldveränderungen in drei Intervallen zwischen 1966 und 2016 zu untersuchen, wurden Zeitreihen von Landsat-Daten und zusätzlich von Luftbildern verwendet. Die Erweiterung der Waldwege wurde aus einer Kombination von Satellitenbildern und topographischen Karten extrahiert. Für die Analyse von Waldveränderungen wurden sowohl pixel- als auch objektbasierte Ansätze verwendet. Räumliche Autokorrelationsindikatoren und räumliche Regressionsmodelle wurden eingesetzt, um Muster von Waldveränderungen und Zusammenhänge zwischen Waldveränderungen und der Erweiterung von Wohngebieten und Straßennetzen zu visualisieren. Darüber hinaus wurde die Erkennung alter und neuer Erdrutsche aus Sentinel-1 und -2 Bildern und DEM-Derivaten unter Verwendung der objektorientierten „Random Forest “-Methode durchgeführt. Ebenfalls mit dem objektbasierten „Random Forest “-Ansatz wurde die Bedeutung von Konditionierungs- und Auslösefaktoren untersucht, welche die Suszeptibilität einer Fläche für Erdrutsche in geschützten und nicht geschützten Wäldern kontrollieren. Die zentralen Erkenntnisse sind, dass die Ausbreitung von Siedlungsflächen und der Ausbau von Landstraßen die Waldverluste vor dem Jahr 2000 zunehmend erhöht haben. Mit dem Ausbau von Wald- und Bergbaustraßen änderten sich jedoch seit den 1980er Jahren die räumlichen Muster der Walddynamik von Waldverlust hin zu Waldfragmentierung und Walddegradierung. Obwohl die orographischen und hydrologischen Merkmale die wichtigsten Einflussfaktoren hinsichtlich Suszeptibilität für das Auftreten von Erdrutschen in Schutzwäldern waren, haben weitere natürliche und anthropogene Auslöser Signifikanz erreicht innerhalb der nicht geschützten Waldflächen: Holzeinschlag und Waldfragmentierung waren dabei die dominierenden anthropogenen Auslöser. Die Studie bestätigt zudem, dass die Parameter für die Erkennung von Erdrutschen und für die Beurteilung der Rutschungs-Suszeptibilität an die verschiedenen Waldgebiete anzupassen sind. In der Modellierung der Beziehung zwischen Waldveränderungen und anthropogenen Einflüssen zeigten räumlich basierte Regressionsmodelle eine höhere Effizienz als das traditionelle Regressionsmodell; allerdings gab es keine klare Priorität innerhalb der räumlichen Modelle. Der „Random Forest “-Ansatz zeigte eine zufriedenstellende Genauigkeit sowohl bei der Kartierung historischer Erdrutsche als auch in der Bestimmung der Rutschungs-Suszeptibilität. Dabei lag die erreichte Genauigkeit in den geschützten Waldgebieten höher. Diese Forschungsarbeit hat vom Menschen verursachte Waldveränderungen untersucht. Da jedoch auch andere abiotische und biotische Faktoren die geschilderten Veränderungen verursachen können, sind weitere Studien notwendig. Diese könnten z. B. Klimaparameter, Waldbrände, Insektenschädigung und andere Naturgefahren einschließen.

Around the world, many forested areas have been and continue to be cleared for expanding agriculture. Canada’s remaining forested lands account for around 9% of the world’s forest cover. Although only a fraction is lost to deforestation annually (0.02%, 2013), Statistics Canada reports that conversion to agriculture is the most significant driver of forest loss. As climate changes and agricultural demand expands, this trend is expected to continue, and ecosystems will continue to be impacted by resulting habitat loss and hydrological changes that can impact infrastructure and communities. Additionally, changes to sediment and nutrient loadings can harm ecosystems and affect the downstream usability of freshwater supplies. The impact of increased sediment and nutrient concentrations in freshwater systems has been extensively documented in the literature. In some extreme cases, it can lead to anoxic ‘dead zones’ in riverine, lacustrine, and marine habitats. Many river systems in Canada have shown elevated nutrient levels in recent years, often tied to the expansion of agricultural land use and destruction of natural forests to increasing nutrient levels in downstream rivers, lakes, and oceans. This study applies numerical modelling to quantify the influence of forest loss, agricultural expansion and the application of best management practices (BMPs) on water quality and quantity in the South Nation Watershed in eastern Ontario, Canada. The land use in the watershed is mainly agricultural (over 60%) with forest (27%) that is unevenly distributed in the basin. Aerial photography surveys from 2008 and 2014 show a steady decline in forest cover. Recent water quality monitoring has shown nutrient concentrations at or above Canadian water quality standards in many parts of the basin. The Soil and Water Assessment Tool (SWAT) was used to model the watershed because of its capacity to simulate comprehensive land management scenarios and assess their impact on a variety of water quantity and parameters quickly and effectively. The work was performed in four steps: 1. Recent land use configurations (2008-2014) in the watershed were acquired, and simplified land use projections based on the direct substitution of cropland for forest land were developed. 2. A numerical model was calibrated and validated for the initial land use scenario. 3. These land use scenarios, as well as more hypothetical scenarios representing more extensive deforestation and reforestation, were used as the basis for hydrological modelling using 31 years of real-world meteorological observations. 4. Idealized vegetated filter strips (VFSs) and grassed waterways (GWWs) were added to the cropped land packages to study the potential of these practices to contribute to the management of water quality. Analysis of the 33 output datasets derived from simulations of the suite of land use scenarios with and without VFSs and GWWs leads to several conclusions, while also raising some questions. Generally, forests significantly reduce sediment, nitrate and phosphorus outputs to streams as well as slightly reducing water yield compared to cropped areas due to an increase in surface runoff, groundwater and lateral flow combined with the absence of tile drainage. Across subbasins, this translates to significant reductions in sediment, nitrate and total phosphorus loadings entering the river reaches and a slight increase in water yield. At the basin outlet near Plantagenet, Ontario, streamflow and sediment loading show to have little sensitivity to changes in forest and crop cover, while increased forest cover leads to significantly reduced nutrient loadings, particularly in late spring and early winter. It is clear from this work that continued deforestation will continue to drive further nutrient enrichment in the South Nation River, while VFSs seems to have a significant potential for offsetting some of this enrichment. Streamflow and sediment loadings, however, are not significantly impacted by foreseeable deforestation. The influence of land use change and BMPs was much more significant in the runoff than in exports from the basin, suggesting there would be value in further examination of water quality and quantity at a higher spatial density to expand on assumptions of in-stream processes made here.

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The seagrass extent has been declining globally. The human activities that are most likely to cause seagrass loss are those which affect the water quality and clarity. However, turbidity following coastal erosion is often left out from marine ecosystem vulnerability indices. This study quantified the coastal erosion for Tsimipaika Bay in northwestern Madagascar by using change detection analysis of satellite imageries. The annual coastal erosion data was then used to create an index for seagrass vulnerability to turbidity following coastal erosion. Considering that the height of seagrass species plays an important role in their survival following turbidity, the seagrass vulnerability index (SVI) was based on two factors; seagrass species height and their distance to the nearest possible erosion place. The results for the coastal erosion showed that the amount of erosion was particularly high in 1996, 2001 and 2009 for Tsimipaika Bay. The highest erosion occurred in 2001 with a land loss area of about 6.2 km2 . The SVI maps revealed that 40% of the seagrass communities had minimum mean SVI values in 2001 and 50% had the maximum mean SVI during the year 2009. This study showed that it is possible to use coastal erosion to measure seagrass vulnerability; however, the index requires configuration such as including the total amount of annual coastal erosion and incorporating bathymetric data. The entire project was built and automated in Jupyter Notebook using Python programming language, which creates a ground for future studies to develop and modify the project.

Energy poverty is defined as the lack of access of households in developing countries to modern energy sources, and their consequent reliance on solid biomass fuels for cooking. So-called “Improved stoves” have been promoted by various public and private actors since the 1970s to tackle various environmental and health challenges associated with biomass use. Impact studies of such projects are usually based on on-site surveys about the stoves’ use, and thus are extremely site-specific, and difficultly generalizable. This thesis project aims to introduce a novel approach to impact assessment of improved cooking stoves on both local energy needs and deforestation in the area. This approach will base most of its figures and assumptions on calculated energy needs rather than survey reports. This will result in a highly flexible energy model, which can be used and adapted to help decision and policy makers in their function. The area of Nyeri County, Kenya, where the author completed a one-month field study, is used throughout the thesis as a case study in order to validate the model.