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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.
291

Quantifying forest degradation and deforestation using Geographic Information System (GIS); a case study in the three provinces, South Kalimantan, East Kalimantan and South-east Sulawesi, Indonesia

Sau, Andi Adriana We Tenri January 2013 (has links)
Forest degradation and deforestation have been pervasive problems in Indonesia and the country is placed second in terms of a high rate of tropical deforestation. Different definitions and different techniques have been used to quantify forest degradation and deforestation in Indonesia, and different factors have been detected as direct and underlying causes. However, almost no quantitative studies have been conducted to relate deforestation and forest degradation to the causes. This study quantifies the rate of forest degradation and deforestation between 2000 and 2009 in three provinces of Indonesia, South Kalimantan, East Kalimantan and South East Sulawesi, as a case study. A geographic information system (GIS) was used to generate geographic datasets to allow quantification; accompanied by a descriptive statistical analysis. Land cover in 2000 and 2009 was used as the basis of analysis. A national land use classification was aggregated into 10 different land use classes. Changes in land use between 2000 and 2009 allowed quantification of the rates of forest degradation and deforestation as well as the association between degradation and deforestation and potential causes. Overall, 95% of primary forest degradation in South Kalimantan, 65% in East Kalimantan, and 46% in SE Sulawesi were associated with direct causes such as forest concessions, mining activities and the government-sponsored transmigration program. The selected direct causes explain 56% of secondary forest deforestation in South Kalimantan, 44% in East Kalimantan and 55% in SE Sulawesi. Results of this study also show that forest degradation and deforestation occurred across the official forest areas. Almost 40% of forest degradation in South Kalimantan and East Kalimantan occurred in conservation forests and production forests respectively; while 57% of forest degradation in SE Sulawesi occurred in protected forests. Deforestation occurred 29% and 34% in the production forests of South Kalimantan and East Kalimantan respectively. In SE Sulawesi, 34% of deforestation occurred in watershed protection forests. This study suggests that current practice in the forest resources management in Indonesia is not effective and efficient enough to mitigate and to halt forest degradation and deforestation. This is due to the lack of consistency in implementing forest land use policy, mistaken policy interventions, and non-synchronised policy between central and local governments. Policy reform is needed to conserve the remaining forest resources and mega-diversity of Indonesia.
292

Stream fusion : practical shortcut fusion for coinductive sequence types

Coutts, Duncan January 2011 (has links)
In functional programming it is common practice to build modular programs by composing functions where the intermediate values are data structures such as lists or arrays. A desirable optimisation for programs written in this style is to fuse the composed functions and thereby eliminate the intermediate data structures and their associated runtime costs. Stream fusion is one such fusion optimisation that can eliminate intermediate data structures, including lists, arrays and other abstract data types that can be viewed as coinductive sequences. The fusion transformation can be applied fully automatically by a general purpose optimising compiler. The stream fusion technique itself has been presented previously and many practical implementations exist. The primary contributions of this thesis address the issues of correctness and optimisation: whether the transformation is correct and whether the transformation is an optimisation. Proofs of shortcut fusion laws have typically relied on parametricity by making use of free theorems. Unfortunately, most functional programming languages have semantics for which classical free theorems do not hold unconditionally; additional side conditions are required. In this thesis we take an approach based not on parametricity but on data abstraction. Using this approach we prove the correctness of stream fusion for lists -- encompassing the fusion system as a whole, not merely the central fusion law. We generalise this proof to give a framework for proving the correctness of stream fusion for any abstract data type that can be viewed as a coinductive sequence and give as an instance of the framework, a simple model of arrays. The framework requires that each fusible function satisfies a simple data abstraction property. We give proofs of this property for several standard list functions. Previous empirical work has demonstrated that stream fusion can be an optimisation in many cases. In this thesis we take a more universal view and consider the issue of optimisation independently of any particular implementation or compiler. We make a semi-formal argument that, subject to certain syntactic conditions on fusible functions, stream fusion on lists is strictly an improvement, as measured by the number of allocations of data constructors. This detailed analysis of how stream fusion works may be of use in writing fusible functions or in developing new implementations of stream fusion.
293

Entre forêts, agroforêts et plantations : analyse des dynamiques paysagères à Bungo, province de Jambi, Indonésie / Between forests, agroforests and plantations : analysis of landscape dynamics in Bungo district, Jambi, Indonesia

Feintrenie, Laurène 08 October 2010 (has links)
Dans le contexte de la transition agraire actuellement en cours en Indonésie, les paysages se transforment rapidement, généralement aux dépens de la forêt. En 2010, le district de Bungo présente une mosaïque paysagère, qui combine des vestiges de forêts à des agroforêts à hévéa et à durian, et à des plantations monospécifiques de palmier à huile et d’hévéa. Les agroforêts sont de plus en plus converties en plantations par les agriculteurs, dans l’espoir d’améliorer leurs revenus. Cette évolution repose sur l’implication de différentes catégories d’acteurs – population, gouvernements, secteur industriel – qui partagent un intérêt commun dans le développement économique du district. Cette thèse analyse en détails les dynamiques de conversion des agroforêts à hévéa en plantations monospécifiques de palmier à huile et d’hévéa. Une approche multiscalaire et transdisciplinaire a été suivie pour articuler les différentes échelles spatiales et sociales, du champ cultivé à la famille étendue, du village au district, et au contexte international. Les communautés locales souhaitent intensifier leurs pratiques agricoles, et participent volontairement et activement au développement des plantations monospécifiques, en particulier du palmier à huile. La conservation des forêts et des agroforêts dans l’intérêt général n’est pas une de leurs préoccupations, mais bien celle de la communauté internationale, représentée par des organisations non gouvernementales et des conventions internationales sur la préservation de l’environnement. / In the wider context of the agrarian transition in Indonesia, changes in landscapes are happening very quickly and generally at the expense of forested lands. In 2010, Bungo district presents a landscape mosaic, combining remnant forest patches to rubber and durian agroforests and monoculture plantations of oil palm and rubber. Agroforests are increasingly converted into monoculture plantations by farmers, in intend to enhance their income. This evolution rests on the investment of different categories of stakeholders – population, governments, industrial sector - who share a common interest in the economic development of the district. This thesis analyses in details the dynamics of rubber agroforests conversion to rubber and oil palm monoculture plantations. A multi-scale and transdiciplinary approach was used to articulate different spatial and social scales, from the cultivated plot to the extended family, from the village to the district, and to the broader international context. Local communities are willing to intensify their agricultural practices, and voluntarily participate in the development of monoculture plantations, in particular of oil palm. The conservation of forests and agroforests in not their concern, but one of the international community, represented by non governmental organizations and international conventions for the preservation of the environment.
294

Ecosystem Services and Disservices in an Agriculture–Forest Mosaic : A Study of Forest and Tree Management and Landscape Transformation in Southwestern Ethiopia

Ango, Tola Gemechu January 2016 (has links)
The intertwined challenges of food insecurity, deforestation, and biodiversity loss remain perennial challenges in Ethiopia, despite increasing policy interventions. This thesis investigates smallholding farmers’ tree- and forest-based livelihoods and management practices, in the context of national development and conservation policies, and examines how these local management practices and policies transform the agriculture–forest mosaic landscapes of southwestern Ethiopia. The thesis is guided by a political ecology perspective, and focuses on an analytical framework of ecosystem services (ESs) and disservices (EDs). It uses a mixed research design with data from participatory field mapping, a tree ‘inventory’, interviews, focus group discussions, population censuses, and analysis of satellite images and aerial photos. The thesis presents four papers. Paper I investigates how smallholding farmers in an agriculture–forest mosaic landscape manage trees and forests in relation to a few selected ESs and EDs that they consider particularly beneficial or problematic. The farmers’ management practices were geared towards mitigating tree- and forest-related EDs such as wild mammal crop raiders, while at the same time augmenting ESs such as shaded coffee production, resulting in a restructuring of the agriculture–forest mosaic. Paper II builds further on the EDs introduced in paper I, to assess the effects of crop raids by forest-dwelling wild mammals on farmers’ livelihoods. The EDs of wild mammals and human–wildlife conflict are shown to constitute a problem that goes well beyond a narrow focus on yield loss. The paper illustrates the broader impacts of crop-raiding wild mammals on local agricultural and livelihood development (e.g. the effects on food security and children’s schooling), and how state forest and wildlife control and related conservation policy undermined farmers’ coping strategies. Paper III examines local forest-based livelihood sources and how smallholders’ access to forests is reduced by state transfer of forestland to private companies for coffee investment. This paper highlights how relatively small land areas appropriated for investment in relatively densely inhabited areas can harm the livelihoods of many farmers, and also negatively affect forest conservation. Paper IV investigates the patterns and drivers of forest cover change from 1958 to 2010. Between 1973 and 2010, 25% of the total forest was lost, and forest cover changes varied both spatially and temporally. State development and conservation policies spanning various political economies (feudal, socialist, and ‘free market-oriented’) directly or indirectly affected local ecosystem use, ecosystem management practices, and migration processes. These factors (policies, local practices, and migration) have thus together shaped the spatial patterns of forest cover change in the last 50 years. The thesis concludes that national development and conservation policies and the associated power relations and inequality have often undermined local livelihood security and forest conservation efforts. It also highlights how a conceptualization of a local ecosystem as a provider of both ESs and EDs can generate an understanding of local practices and decisions that shape development and conservation trajectories in mosaic landscapes. The thesis draws attention to the need to make development and conservation policies relevant and adaptable to local conditions as a means to promote local livelihood and food security, forest and biodiversity conservation, and ESs generated by agricultural mosaic landscapes. / <p>At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 2: In press. Paper 3: Submitted. Paper 4: Manuscript.</p>
295

Analyse de la détérioration de la forêt de la Cordillère de la Costa dans le sud chilien : géomatique et modélisation prospective appliquée sur une forêt patrimoniale de la province d'Osorno (41º 15’ - 41º 00’ latitude Sud) / Analysis of the deterioration of forest in the Cordillera de la Costa in southern Chile : geomatics and prospective modeling applied to a national forest in the province of Osorno (41°15' - 41°00' south latitude)

Toro Balbontin, Darío 08 September 2014 (has links)
On étudie une zone de la Cordillère de la Costa au sud du Chili (41°15'S-41°00'S), habitée par l'ethnie Mapuche. Là, il y a encore des précieuses forêts tempérées, qui ont une haute priorité de conservation au plan mondial. Mais, il est constaté, un processus continu de transformation lié à l'extraction de bois de chauffe, l'élevage extensif, la perturbation de l'habitat du conifère Fitzroya cupressoides, et le déploiement des plantations forestières. Sur la base d'une classification multi-temporelle d'images satellite, une modélisation spatio-temporelle a été mise en œuvre pour comprendre et anticiper la dynamique de la détérioration de la forêt. L'analyse rétrospective révèle qu'entre 1976 et 2008, la forêt a été réduite 12400 ha, soit un taux de déforestation 0,25% par an. 20 modèles de déforestation sont calibrés, 4 d'entre eux sont sélectionnés pour construire des scénarios prospectifs. La simulation prévoit que la diminution de forêt entre 2008 et 2040 pourrait atteindre 13000 ha. Deux autres modèles mis en œuvre simulent l'évolution de la qualité de l'habitat de F. cupressoides. Les scénarios prévoient une augmentation de la surface détériorée ; l’extrapolation à partir de la période d’apprentissage 2001-2008 pendant laquelle la plus grande part de terres indigènes a été légalisée, par rapport à la période précédente à 2001, prédit une augmentation plus significative de la surface détériorée. On fournit un outil pour amplifier la gestion territoriale des systèmes environnementaux toujours non incorporée dans la planification chilienne. Enfin, la thèse met également d'intéressantes comparaisons entre modèles qui diffèrent par rapport aux paramètres de calibration. / SAn area of the Cordillera de la Costa is studied in southern Chile (41°15'S - 41°00'S), inhabited by ethnic Mapuche. There are still valuable temperate forests that have high conservation priority worldwide. But it is found, a continuous process of transformation related to the extraction of firewood, ranching, disruption of habitat conifer Fitzroya cupressoides, and deployment of forest plantations. Based on a multi-temporal satellite images classification, a spatial-temporal modeling was implemented to understand and predict the dynamics of the deterioration of the forest. Retrospective analysis revealed that between 1976 and 2008, the forest has been reduced 12,400 ha, a deforestation rate of 0.25% per annum. 20 models of deforestation are calibrated, 4 of them are selected to construct scenarios. The simulation predicted that reductions of forest between 2008 and 2040 could reach 13,000 ha. Two other models implemented simulate changes in habitat quality F. cupressoides. Scenarios predict an increase in the damaged surface; extrapolating from the learning period 2001-2008 during which the largest share of indigenous lands was legalized, compared with the previous period to 2001, predicts a significant increase in the damaged surface. In this way, it provides a tool to enhance the local management of environmental systems still not incorporated into the Chilean planning. Finally, the thesis also makes interesting comparisons between models that differ with respect to the calibration parameters.
296

Litígios estratégicos ambientais e justiça participativa: o caso do desmatamento nos projetos de assentamento de reforma agrária na Amazônia Legal / Strategic environmental litigation and public participation: the case of deforestation in agrarian reform settlement projects in Legal Amazon

Albuquerque, Carolina de 17 March 2017 (has links)
Esta pesquisa caracteriza-se pela interdisciplinaridade e tem como eixo integrador o desmatamento em Assentamentos de Reforma Agrária na Amazônia Legal, sob responsabilidade do INCRA, com foco na atuação do Grupo de Trabalho Amazônia Legal - GTAL, do Ministério Público Federal - MPF e na percepção jurídico-ambiental dos assentados no Estado de Rondônia. As metodologias utilizadas foram: estudo de caso, pesquisa documental, análise de conteúdo, pesquisa de campo, entrevistas com questionários abertos e fechados e análise estatística. As principais bases teóricas utilizadas foram: Aplicação Seletiva dos Direitos Sociais, Princípio da Proporcinalidade, Justiça Ambiental Participativa, Litígio Estratégico e Voluntarismo Político. Conclui-se que as atividades do GTAL, do MPF, do INCRA e do Poder Judiciário, até o momento, neste caso específico, não envolveram os assentados, do que decorre a necessidade de maior participação desses stakeholders para ampliação de resultados positivos em casos difíceis ambientais, no manejo de litígio estratégico. / This research is characterized by interdisciplinarity and focus the deforestation in Agrarian Reform Settlements, in the Legal Amazon, under the responsibility of INCRA, in order to examine the function of the Legal Amazon Working Group (GTAL), the Federal Public Prosecutor (MPF) and the legal and environmental perception of the settlers in the State of Rondônia. The methodologies used were: case study, documentary research, content analysis, field research, interviews with open and closed questionnaires and statistical analysis. The main theoretical bases used were: Selective Application of Social Rights, Principle of Proportionality, Participatory Environmental Justice, Strategic Litigation and Political Voluntarism. It is concluded that the activities of the GTAL, Public prosecutor, INCRA and the Judiciary, so far, in this specific case, did not involve the settlers, resulting in the need for greater participation of these stakeholders to increase positive results in difficult environmental cases, in litigation management strategic.
297

O papel dos remanescentes florestais na retenção da biodiversidade e conservação da água em uma paisagem fragmentada na região central de Rondônia / The role of forest remnants on biodiversity retention and water conservation in a fragmented landscape of central region of Rondônia state, Brazil

Begotti, Rodrigo Anzolin 19 December 2013 (has links)
Em toda a superfície terrestre o uso humano está transformando grande parte das florestas, especialmente na região tropical. O desmatamento de florestas tropicais é uma das principais fontes de emissão de gases do efeito estufa e a principal ameaça à conservação de espécies e dos serviços ambientais prestados pela floresta. Dentro desse contexto que também envolve a fragmentação do habitat, o objetivo desse trabalho foi analisar como as relações entre a dinâmica do uso e cobertura da terra afetaram a estrutura e composição da comunidade de vertebrados, e também a qualidade da água em riachos no Sudoeste da Amazônia brasileira. Nós analisamos esse processo em uma área de aproximadamente 50000 km² por meio de mapas classificados a partir de imagens de satélite ao longo de 36 anos de monitoramento. Nós observamos uma perda de floresta da ordem de 24826 km² relacionada, dentre outros fatores, à expansão da malha viária de 3158 km para 12863 km de extensão, tornando a área de estudo como uma das mais desmatadas de toda a Amazônia brasileira. A dinâmica do uso e cobertura da terra ao longo da série temporal mostra que as paisagens com desmatamento mais recente apresentaram fragmentação mais intensa do que aquelas com desmatamento mais antigo e onde ocorreu pequena ou nenhuma derrubada de floresta. Os resultados da inferência com modelos generalizados de mínimos quadrados mostram que a proximidade das estradas é um dos fatores que contribuem para o aumento no desmatamento, principalmente em áreas com menor declividade e distantes dos rios. Os modelos lineares generalizados com os maiores valores de importância relativa para explicar a riqueza de espécies, biomassa agregada e o índice de vulnerabilidade à caça foram compostos pela área, número e distância entre os fragmentos como variáveis independentes. A área de floresta é importante também para a conservação da água, principalmente quanto à sua proporção na faixa de 100 m ao longo dos riachos amostrados. Levando-se em conta as características dos solos predominantes na microbacias e a sazonalidade, principalmente nos meses chuvosos, a redução de floresta próxima aos rios é responsável pelo aumento nas concentrações de alumínio, fosfato, sedimentos em suspensão, amônio e nitrato, de acordo com nossos modelos lineares generalizados. Ao final, considerações foram feitas a respeito do aumento da fiscalização e da regularização fundiária para impedir que a fronteira do desmatamento continue a avançar sobre áreas de floresta primária, e que o manejo das áreas fragmentadas inclua a restauração da floresta, principalmente ao longo dos rios para diminuir o isolamento dos fragmentos remanescentes. Nós ressaltamos também, a necessidade de se estudar como as perturbações recorrentes nos fragmentos como corte seletivo e incêndios continuam afetando a comunidade de vertebrados que ocorrem fora das áreas contínuas de floresta. / Extensive areas across the Earth surface have been modified by human land uses, particularly in the tropical region. Deforestation is one of main sources of emissions of greenhouse gases and the main threat to the conservation of biodiversity and ecosystem services provided by tropical forests. In the context of human-modified landscapes, including forest fragmentation, the main goal of this work is to understand the relationships between land use and land cover dynamics and the changes in the structure and composition of forest vertebrate community and also, the alterations in the quality of surface water in catchments. We assess land use dynamics about 50,000 km² of study area located in Southwestern Brazilian Amazon. By mean of maps of land cover classified from satellite images based in a 36-year monitoring, we observed a forest loss of 24,826 km² related to the expansion of road network from 3158 km to 12863 km in the same period. This result makes the study area as the most deforested of entire Brazilian Amazon. The land use dynamics show that fragmentation is higher in recent deforestation frontier than in both older deforestation and landscapes with few or no deforestation detected. Our results from inference with generalized least square models show that distance to the roads affects negatively the deforestation rates, mainly in flat areas and near to small and large rivers. The generalized linear models with higher relative importance to explain the species richness, aggregate biomass and the index of hunting vulnerability had as predictors the fragment area, number of patches and distance between fragments as major attributes of the landscape that affects the vertebrate community. The forest is important for maintenance of stream water quality, particularly if there is forest cover in the 100 m strips alongside the streams, considering the soil characteristics such as proportion of bases and seasonality. In our GLM multi-model analysis, the higher proportion of forest in surroundings the streams contributes to the increasing of concentrations in the rainy season of aluminum, phosphate, suspension sediments, ammonium and nitrate. At the end, we made consideration about law enforcement and landownership, to preclude the deforestation toward extensive areas of pristine forest. Moreover, we suggest that in fragmented landscapes the conservation efforts to be concentrated in forest restoration, mainly near to rivers, to reduce the isolation of the fragments. We highlighted the importance in monitoring the biodiversity responses to recurrent disturbing sources such as selective logging and accidental forest fires in fragmented landscapes.
298

A biogeoquímica do rio Urupá, Rondônia / The biogeochemistry of Urupá river, Rondônia

Bolson, Marcos Alexandre 19 October 2006 (has links)
O estado de Rondonia possui hoje o 8° maior rebanho bovino do pais. Essa caracteristica o torna urn estado essencialmente pecuarista, muito embora ja se perceba um avanco na atividade agricola. Em termos de impacto ambiental, a pecuaria é extremamente agressiva, pois nas praticas antigas de manejo do gado era comum a conversdo direta da floresta em pastagem e consecutivas queimas nos primeiros anos para a limpeza da biomassa remanescente da floresta. Este trabalho tem por objetivo avaliar possiveis alteracOes na biogeoquimica das aguas do rio Urupd mediante esse cenario de contraste entre areas que preservam as caracteristicas naturais e areas corn elevado grau de perturbacao. Corn este intuito, foram realizadas amostragens em seis pontos ao longo do rio Urupd, de forma a termos um gradativo cendrio de perturbacdo no use do solo. 0 primeiro ponto refere-se ao setor da nascente, e é o mais preservado da bacia, corn praticamente 100% de suas caracteristicas naturais, ao passo que o Ultimo, que abrange toda a bacia de drenagem, mantem aproximadamente 51% de floresta. Para essas unidades de drenagens foram analisadas as concentraeOes de ions maiores (Nat, Kt, Mg2+, Ca2+, HCO3\", CY e SO42), de carbono organic° dissolvido (COD), e a razao isotOpica do carbono inorganic° dissolvido (613C do CID). Em geral, os resultados mostraram que, apesar da quantidade de pastagem aumentar de uma unidade de drenagem para outra, e as concentracCies de ions dissolvidos aumentarem consideravelmente, as diferencas nas concentracOes apresentam melhor relacdo coin a distribuicao da Capacidade Efetiva de Troca de Cations, caracteristica inerente dos solos. Portanto, em termos das concentracOes de ions maiores, apesar do extenso desmatamento, ndo ha indicios de que os processos naturais tenham sido suplantados por antropogenicos como principais fatores determinantes da dinamica neste sistema. Contudo, a distribuicdo espacial e temporal das concentraceies de carbono organic° dissolvido demonstram que o aumento do percentual de pastagens relaciona-se corn concentracOes significativamente maiores desta forma de C nas aguas do canal principal. A composicao isot6pica (613C) do carbono inorganic° dissolvido demonstrou que, nos setores mais a juzante da bacia do rio Urupd, a quimica das aguas e predominantemente determinada por processos de intemperismo de rochas carbonatadas / The state of Rondonia has the 8th largest cow herd of the country. This characteristic makes it a state where cattle raising dominates the landscape, although other agricultural uses are becoming noticeable. In terms of environmental impacts cattle raising is extremely aggressive, since early practices were based on slash and burn techniques. This study intends to evaluate changes in the biogeochemistry of the Urupá river waters in such a scenario of remaining pristine areas and heavily impacted ones. In order to understand that, 6 sampling stations were established along the river, at different degrees of land use changes. The first station refers to the headwaters and is the most pristine reach, with almost 100% of its original vegetation, whereas the the last corresponds to the whole basin and has only 51% or remaining forests. The waters where analyzed for the concentrations of major ions (Na+, K+, Mg2+, Ca2+, HCO3-, Cl- e SO42-), dissolved organic carbon (DOC) and the isotopic composition (?13C) of dissolved inorganic carbon (DIC). Generally, the results show that, although the percentages of pasture and major ion concentrations increase significantly along the basin, the latter relates better with a natural characteristic of the soils, which is the effective cation exchange capacity. Consequently, in terms of the ionic concentration of these waters, even with the extensive deforestation observed in the basin, it is not possible to conclude that anthropogenic processes have overcome natural ones as main forces driving the dynamics of this system. However spatial and temporal DOC distributions show that pastures are directly related to increases of this form of C in these waters. DIC isotopic composition (?13C) shows that the chemistry of the Urupá river lower reaches is controlled by the weathering of carbonate rocks
299

Impacto das atividades produtivas na dinâmica da paisagem do assentamento Matupi, estado do Amazonas / Impact of Productive Activities in Landscape Dynamics Matupi Settlement, State of Amazonas

Silva, Viviane Vidal da 20 September 2012 (has links)
As causas relacionadas ao desmatamento que ocorre na região Amazônica estão vinculadas aos diferentes usos e ocupações dessa área, entre eles os assentamentos rurais implantados pelo INCRA. Desta forma, com um estudo de escala local, o objetivo desta pesquisa foi investigar quais são os fatores sociais, econômicos e institucionais que influenciam no uso da terra e no desmatamento no Projeto de Assentamento Matupi, localizado no município de Manicoré, sul do estado do Amazonas. Para a avaliação das mudanças no uso da terra e do desmatamento foram utilizadas as informações geradas pelo PRODES/INPE no período de 2000-2010. As características sócio-econômicas foram levantadas a partir da aplicação de 121 questionários com os responsáveis pelo lote no assentamento Matupi. Utilizou-se o Modelo de Regressão Multivariada (MRM) para selecionar as variáveis sociais, institucionais e econômicas (variáveis independentes) que explicam o uso da terra e o desmatamento (variável dependente) no PA Matupi. No período analisado observou-se que a conversão de áreas de floresta em uso da terra tem aumentado no PA Matupi e para os lotes da amostra de 121 entrevistados, 90,9% dos responsáveis pelo lote utilizam mais de 20% de sua área, principalmente com a atividade da pecuária. Das 28 variáveis independentes, apenas atividade atual do lote, assistência técnica, utilização de equipamentos e máquinas, responsável pelo lote, local de moradia antes da chegada ao assentamento, origem dos responsáveis pelo lote, produtos comercializados e comercialização dos produtos foram selecionadas para explicar o uso da terra e o desmatamento na área estudada. Desta forma, estudos locais e que integrem os fatores sociais, institucionais e econômicos são necessários para se avaliar a real contribuição dos projetos de assentamentos do INCRA no desmatamento da região, contribuindo para o planejamento de novos assentamentos na região, que visem ao desenvolvimento social, econômico e ambiental. / Causes related to the deforestation in the Amazon region are linked to different uses and occupations of this area, including rural settlements implemented by Incra. Thus, through a local-scale study, the objective of this research was to investigate which are the social, economic and institutional influences on land use and deforestation in Matupi Settlement Project, in the municipality of Manicoré, in the southern region of the state of Amazonas. For the assessment of changes in land use and deforestation, information generated by PRODES / INPE, in the period 2000-2010, were used. The social-economic characteristics were obtained from the application of 121 questionnaires with those responsible for the lot in the Matupi settlement. We used the Multivariate Regression Model (MRM) to select the variables social, institutional and economic factors (independent variables) that explain land use and deforestation (dependent variable) in PA Matupi. The analysis showed that the conversion of forest land to use has increased in Matupi PA and for 121 respondents, 90.9% use more than 20% of the lot, especially with the activity of livestock. Of the 28 independent variables, only the current activity in the lot, technical assistance, use of equipment and machinery, responsible for the lot, place of residence before arriving at the settlement, origin of the responsible for the plot, and marketing of products and marketed products have been selected to explain the land use and deforestation in the area. Thus, local studies integrating social, economic and institutional factors are needed to assess the real contribution of the INCRA settlement projects in the deforestation of the region, contributing to the planning of new settlements in the region, aimed at the social, economic and environmental development.
300

Variabilidade temporal e espacial das chuvas e do balanço hídrico no estado de Rondônia: caracterização e análise de tendência / Temporal and spatial variability of rainfall and water balance in the state of Rondônia, Brazil: characterization tendency analysis

Furlan, Deise Nunes 22 May 2009 (has links)
Com os significativos índices de desmatamento na região Amazônica, grande é a preocupação sobre os efeitos que essa mudança na cobertura vegetal pode ter sobre a dinâmica climática e pluviométrica dessa região, como também em outras localidades do Brasil. Dentro desse contexto, o presente trabalho teve como objetivo verificar se os atuais índices de desmatamento em Rondônia, ocorridos nos últimos 30 anos, são suficientes para contribuir para a modificação do regime hídrico e pluviométrico. Os dados utilizados no presente estudo foram obtidos juntos à Agência Nacional de Águas ANA e são provenientes de 29 postos pluviométricos instalados no estado de Rondônia. Essa é uma região de pequena disponibilidade de dados meteorológicos devido à colonização recente, sendo que as séries dificilmente passam de 30 anos de dados. Além disso, essas séries são comprometidas por falhas na coleta de dados, que em algumas localidades chegam a apresentar mais de um ano sem registro. Para que as análises fossem possíveis, foi realizado o preenchimento das falhas nas séries de dados através do gerador de dados CLIMGEN. Em seguida, os dados foram analisados pelo método de Duplas Massas para que eventuais falhas e inconsistências nas séries preenchidas pelo CLIMGEN fossem detectadas. Como passo seguinte, os dados foram submetidos ao ajuste de distribuição de probabilidade pela função Gama, para que fossem identificadas regiões homogêneas quanto à distribuição de probabilidade da chuva em Rondônia. Acompanhando essa análise foi utilizada a análise de agrupamento para que fossem identificas as localidades e os meses com precipitação semelhante. Finalmente, os dados de precipitação foram submetidos ao teste de tendência Mann- Kendall, assim como as variáveis do balanço hídrico seqüencial das localidades de Ouro Preto dOeste e Porto Velho. Os resultados mostram que o CLIMGEN é uma ferramenta que pode ser utilizada no preenchimento de falhas em séries de dados em Rondônia, porém o método de Duplas Massas identificou inconsistências em duas localidades, sendo que as mesmas foram descartadas nas análises seguintes. Quanto à função gama foi verificado um menor grau de assimetria na distribuição de probabilidade da precipitação nos meses mais chuvosos. Nos meses secos, junho, julho e agosto, a distribuição de probabilidade da precipitação é mais assimétrica, sendo semelhante entre todas as localidades. Acompanhando a distribuição gama, a análise de agrupamento mostrou uma heterogeneidade espacial na distribuição da precipitação. Finalmente, as análises de tendência não identificaram mudanças sistemáticas que indiquem que o estado de Rondônia esteja passando por mudanças no regime pluviométrico no período analisado, sendo as tendências observadas possivelmente decorrentes da variabilidade climática natural. As séries de temperatura máxima e mínima de Porto Velho e Ouro Preto dOeste apresentaram tendências, com indícios de aumento principalmente da temperatura mínima. Quanto às análises de tendência nas variáveis do balanço hídrico foram verificadas tendências de aumento principalmente da ETR e ETP. Os resultados permitiram concluir que apesar do significativo aumento da área desmatada em Rondônia, isso ainda não foi suficiente para que mudanças no clima fossem identificadas, sendo necessárias análises de séries mais longas. / Amazon deforestation rate has been significant, resulting in a great concern about the effect that the reduction of the forest can have on the climatic dynamics in this region, as well as in other brazilian locations. In such context, the present work aimed to verify if the current rate of deforestation in Rondônia, last 30 years has been contributed for changes in the rainfall and balance patterns. Data from 29 rainfall stations in Rondônia State which belongs to the National Water Agency ANA were used for this purpose. This is a region of small availability of weather data due to recent settling, with the data series hardly passing of 30 years. Moreover, those data series are compromised by imperfections in the collection of data, resulting in missing data. To have this study feasible, the through the weather missing data were filled out data generator CLIMGEN. After that, the data was analyzed by the method of Double Masses so that imperfections and inconsistencies in the series filled out with CLIMGEN were detected. As a next step, the data were submitted to the adjustment of the Gamma distribution of probability to identify homogeneous regions in relation to the rainfall distribution of probability in Rondônia. Sveh analysis was applied to identify the localities and months with similar rainfall pattern. Finally, the rainfall data was submitted to Mann-Kendall trend test, as well as the variables of the sequential water balance in Ouro Preto dOeste and Porto Velho locations. The results showed that the CLIMGEN is a tool that can be used to fill out missing data in series of Rondônia; however the method of Double Masses identified inconsistencies in two localities, which were not considered in the analyses. The Gamma distribution function presented a smaller degree of asymmetry in the distribution of rainfall probability in the rainy months. Dry months, like in June, July and August, the distribution of rainfall probability is more asymmetrical, being similar among all evaluated locations. Following Gamma the distribution, the cluster analysis showed spatial heterogeneity in the rainfall distribution. Finally, the tendency analyses did not identified systematic changes which indicated that Rondônia State is having changes in the rainfall pattern during the analyzed period, being verified only oscillations of natural order in the climate. The series of maximum and minimum temperature of Porto Velho and Ouro Preto dOeste presented positive tendency, mainly in the minimum temperature. For the variables of the water balance, positive tendencies were detected for ETR and ETP. The results allowed to conclude that although the significant increase of the deforested area in Rondônia, this was not enough yet to cause changes in the climate, being necessary analyses of longer series.

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