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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.
51

Linkage Between Mangrove Fish Community and Nearshore Benthic Habitats in Biscayne Bay, Florida, USA: A Seascape Approach

Santos, Rolando O. 01 April 2010 (has links)
The role of mangroves as essential fish habitat has been a focus of extensive research. However, recent evidence has shown that this role should not be evaluated in isolation from surrounding habitats such as seagrass beds and hard-bottom communities. For example, submerged aquatic vegetation (SAV) communities provide potential sources of food and shelter for fish species that may reside in the mangroves, but may also undergo ontogenetic migrations and daily home-range movements into neighboring habitats. The connectivity between the mangrove fish community and the surrounding seascape may be influenced by the level of patchiness, fragmentation, and spatial heterogeneity of adjacent SAV habitats (i.e., SAV seascape structure). The spatial patterns and heterogeneity of SAV seascape structures are driven by internal and external regulatory mechanisms operating at different spatial and temporal scales. In addition, it is likely that many fish species inhabiting the mangrove zones have different home ranges, and foraging and migratory patterns; therefore, different mangrove fish species may respond to seascape heterogeneity at different scales. There are few studies that have assessed the influence and connectivity of benthic habitats adjacent to mangroves for estuarine fish populations at multiple scales. The present research used an exploratory seascape approach in Biscayne Bay (Florida, USA) to evaluate patterns in the patch composition and configuration of SAV communities, and to examine relationships between seascape structural metrics and the abundance, diversity, and distribution of fishes that utilize the adjacent mangrove shoreline as nursery and/or adult habitat. This seascape approach consisted of: a) the multi-scale characterization of the SAV distribution across the seascape with metrics developed in Landscape Ecology, Geographic Information Systems and Remote Sensing; b) multivariate analyses to identify groups with significantly distinct SAV seascape structures within the most heterogeneous scale, and identify possible mechanisms driving the observed SAV seascape structures; and c) an assessment of the mangrove fish community responses to SAV seascape structures. By applying a set of multivariate analyses (e.g., ANOSIM, MDS plots, hierarchical clustering), the buffer within 200 m from shore was identified as the scale with the highest structural heterogeneity. At this scale, two major SAV seascape structures (i.e., areas with similar SAV spatial arrangement and composition) were identified: a fragmented SAV seascape (FSS) structure and a continuous SAV seascape (CSS) structure. Areas with CSS were characterized by large, uniform SAV patches. In contrast, areas with FSS were characterized by a higher density of smaller, more complex SAV patches. Furthermore, the areas with CSS and FSS structures clustered in zones of the bay with distinct salinity properties. The areas with CSS structures were mostly located in zones characterized by high and stable salinity. However, the areas with FSS concentrated in zones that are influenced by freshwater discharges from canals and with low and variable salinity. The responses of fish diversity metrics were not constrained to the scale at which the greatest spatial heterogeneity of SAV seascape structures was observed (i.e., the seascape composition and configuration within 200 m from shore), but was related to SAV seascape characteristics across different scales. The majority of the variability of the fish diversity metrics in the mangrove shoreline was explained by SAV seascape structures within the smaller scales (i.e., 100-400 m from shore), and SAV seascape structures that represented the level of fragmentation and/or the percent of suitable habitat. Different conceptual models were proposed to illustrate and understand the ecological dynamics behind the relationship between the diversity of the mangrove fish community and the structure of the adjacent SAV seascape. In general, the diversity and abundance of fishes is influenced by the type and level of fragmentation of the SAV seascape, which, in turn, influence the proportion of the seascape used for foraging and refuge by fish. In conclusion, this research quantified how the release of large pulses of freshwater into near-shore habitats of coastal lagoons can influence the seascape structure of SAV communities. Namely, freshwater inputs produce fragmentation in otherwise fairly homogeneous SAV meadows. The outcome of this research highlights the importance of seascape characteristics as indicators of ecosystem-level modifications and alterations affecting the spatial distribution, assemblage, and diversity of marine nearshore habitats in coastal regions heavily influenced by human activities. In addition, the results illustrated the cascading effects and synergistic influences of near-shore habitat spatial assemblages on the composition and diversity of estuarine fish communities. Lastly, and very importantly, the relationships established in this project provide quantitative and qualitative information on patterns of species-habitat associations needed for the improved synergistic management and protection of coastal habitats and fisheries resources.
52

Analysing and modelling spatial patterns to infer the influence of environmental heterogeneity using point pattern analysis, individual-based simulation modelling and landscape metrics

Hesselbarth, Maximilian H.K. 06 April 2020 (has links)
No description available.
53

Erfassung der Landnutzungsstruktur in Sachsen und im Randbereich des Ballungsraumes Dresden

Walz, Ulrich January 1999 (has links)
Der südöstliche Randbereich des Verdichtungsraumes Dresden ist sowohl naturräumlich als auch von der Nutzung her sehr heterogen strukturiert. Hier treffen die Naturräume des Elbtales, des Erzgebirgsvorlandes und der Sächsischen Schweiz aufeinander. Städtische Nutzungen wie Wohn- und Industriegebiete in den Städten Dresden, Heidenau und Pirna stehen ländlichen Nutzungen wie Ackerbau und Intensivobstbau, aber auch Rohstoffabbau in den Kiesgruben gegenüber. Ein Schwerpunkt der Arbeit in diesem Raum lag daher in der quantitativen Erfassung und flächenbezogenen Darstellung von Parametern, die die unterschiedlichen nutzungsbedingten Strukturen im Raum beschreiben und quantifizieren. Dabei standen folgende Fragen im Vordergrund: – Welche Parameter wurden bisher erfaßt und können herangezogen werden? – Wie lassen sich Methoden der Fernerkundung zur großräumigen Ableitung solcher Parameter verwenden? Welche Klassifizierungs- bzw. Filteralgorithmen müssen dazu eingesetzt werden? – Welche Informationen müssen zusätzlich über ein Geo-Informationssystem eingebracht werden? Um das Verhalten der Indizes auf unterschiedlichen räumlichen Ebenen untersuchen zu können, wurden Strukturmaße für die regionale Ebene und den gesamten Freistaat Sachsen bestimmt. Die Berechnung erfolgte mit dem Programm FRAGSTATS. Sowohl für Raster- als auch Vektordaten können damit Maßzahlen für Nutzungseinheiten („Patches“), Nutzungsklassen und für die gesamte Landschaftseinheit ermittelt werden.
54

Kolektivizace zemědělství a její promítnutí do krajiny. Případová studie katastrálního území Široký Důl / Collectivization of agriculture and its projection to the landscape. Case study of cadastral area Široký Důl

Kocmanová, Pavlína January 2010 (has links)
Diplomová práce Kolektivizace zemědělství a její promítnutí do krajiny ABSTRACT I searched changes in the cultural landscape structure in the relation with social processes in the time period 1937-2010 in my thesis. The research refers to the second half of 20th century, or more precisely, to the era of collectivization of Czechoslovak agriculture. In consequence of collectivization, the landscape was ecologically devastated and overall the nature of Czech countryside changed. Analysis of the landscape structure has form of case study of cadastral area of Široký Důl. I interpreted landscape changes from historical aerial photos and then analyzed the changes by geographical information systems. The results of those analyses are indicators (landscape metrics), by which I interpreted conditions of landscape in particular time. I confronted the changes in the landscape structure with social processes, which are described in theoretical part of thesis according to background research. Result of my thesis is general story of particular landscape, whose structure changed fundamentally in consequence of collectivization of agriculture. Key words: landscape structure, collectivization, landscape metrics, GIS, cultural landscape, aerial photos, Široký Důl
55

Remote Sensing of Urbanization and Environmental Impacts

Haas, Jan January 2013 (has links)
The unprecedented growth of urban areas all over the globe is nowadays maybe most apparent in China having undergone rapid urbanization since the late 1970s. The need for new residential, commercial and industrial areas leads to new urban regions challenging sustainable development and the maintenance and creation of a high living standard as well as the preservation of ecological functionality. Therefore, timely and reliable information on land-cover changes and their consequent environmental impacts are needed to support sustainable urban development.The objective of this research is the analysis of land-cover changes, especially the development of urban areas in terms of speed, magnitude and resulting implications for the natural and rural environment using satellite imagery and the quantification of environmental impacts with the concepts of ecosystem services and landscape metrics. The study areas are the cities of Shanghai and Stockholm and the three highly-urbanized Chinese regions Jing-Jin-Ji, the Yangtze River Delta and the Pearl River Delta. The analyses are based on classification of optical satellite imagery (Landsat TM/ETM+ and HJ-1A/B) over the past two decades. The images were first co-registered and mosaicked, whereupon GLCM texture features were generated and tasseled cap transformations performed to improve class separabilities. The mosaics were classified with a pixel-based SVM and a random forest decision tree ensemble classifier. Based on the classification results, two urbanization indices were derived that indicate both the absolute amount of urban land and the speed of urban development. The spatial composition and configuration of the landscape was analysed by landscape metrics. Environmental impacts were quantified by attributing ecosystem service values to the classifications and the observation of value changes over time. ivThe results from the comparative study between Shanghai and Stockholm show a decrease in all natural land-cover classes and agricultural areas, whereas urban areas increased by approximately 120% in Shanghai, nearly ten times as much as in Stockholm where no significant land-cover changes other than a 12% urban expansion could be observed. From the landscape metrics analysis results, it appears that fragmentation in both study regions occurred mainly due to the growth of high density built-up areas in previously more natural environments, while the expansion of low density built-up areas was for the most part in conjunction with pre-existing patches. Urban growth resulted in ecosystem service value losses of ca. 445 million US dollars in Shanghai, mostly due to a decrease in natural coastal wetlands. In Stockholm, a 4 million US dollar increase in ecosystem service values could be observed that can be explained by the maintenance and development of urban green spaces. Total urban growth in Shanghai was 1,768 km2 compared to 100 km2 in Stockholm. Regarding the comparative study of urbanization in the three Chinese regions, a total increase in urban land of about 28,000 km2 could be detected with a simultaneous decrease in ecosystem service values corresponding to ca. 18.5 billion Chinese Yuan Renminbi. The speed and relative urban growth in Jing-Jin-Ji was highest, followed by the Yangtze River Delta and the Pearl River Delta. The increase in urban land occurred predominately at the expense of cropland. Wetlands decreased due to land reclamation in all study areas. An increase in landscape complexity in terms of land-cover composition and configuration could be detected. Urban growth in Jing-Jin-Ji contributed most to the decrease in ecosystem service values, closely followed by the Yangtze River Delta and the Pearl River Delta. / <p>QC 20130610</p>
56

Dinâmica de uso das terras nos municípios de Bonito, Jardim e Bodoquena (MS) e o estado e conservação dos recursos biológicos do Parque Nacional da Serra da Bodoquena e de sua zona de amortecimento / Spatial and temporal dynamics of land use in Bonito, Jardim and Bodoquena (MS) Municipalities, and the conservation state of the biological resources in the Serra da Bodoquena National Park buffer zone

Silva, Normandes Matos da 31 March 2008 (has links)
A pesquisa abordou o processo de uso e ocupação das terras nos municípios de Bodoquena, Bonito e Jardim, situados na borda leste do Parque Nacional da Serra da Bodoquena (PNSB), região sudoeste de Mato Grosso do Sul. Além disso, foi estudado o estado de conservação, em termos de estrutura e configuração da paisagem, dos remanescentes de cerrado e floresta contidos no interior do PNSB e em sua zona de amortecimento. O objetivo foi o de analisar a dinâmica de ocupaçao das terras nos municípios mencionados nos últimos 18 anos, com vistas à subsidiar estratégias de planejamento do uso e ocupação das terras ideal para a região. Objetivou-se também analisar a dinâmica espacial e temporal da paisagem que compõe o PNSB e sua zona de amortecimento, visando à conservação da biodiversidade local. Para isso, foi utilizado um sistema de informação geográfica (SIG) para elaboração de mapas temáticos e de um banco de dados georreferenciado. A determinação do grau de conservação do PNSB e da sua zona de amortecimento se deu mediante a utilização de métricas de paisagem, e da adoção dos preceitos da Teoria dos Grafos. O capítulo 1 demonstrou, por meio dos mapas gerados para os municípios de Bodoquena, Jardim e Bonito, dos anos de 1986 e 2004, que ocorreu uma perda de área nativa e um conseqüente crescimento da matriz antrópica composta por pastagens (principalmente) e culturas agrícolas. Apenas em Bodoquena os remanescentes vegetais tiveram maior porcentual que as áreas de pastagens e lavouras. Pode-se observar que a região estudada, passa por um processo de conversão de habitats naturais, outrora contínuos, para uma paisagem composta por fragmentos de cerrados, campos e florestas. O capítulo 2 mostrou que as fisionomias florestais e de cerrado, apresentaram-se em melhor estado de conservação em 1986 que em 2004. Além disso, foi possível observar que os remanescentes das formações vegetais acima citadas, apresentaram-se em melhor estado de conservação no interior do PNSB, que em sua zona de amortecimento. O mapa de relevância dos remanescentes de floresta, considerando as notas combinadas das métricas de forma e área das manchas indicou, quais são as áreas prioritárias para serem protegidas, por possuírem características adequadas para a persistência da biodiversidade florestal presente no PNSB e em sua zona de amortecimento. O setor norte se destacou por apresentar remanescentes com valores alto e extremamente alto com relação à relevância. O mesmo setor norte possui um maior número de pontos de sensibilidade à quebra de conectividade entre as manchas de floresta. Nesta região pode-se observar que a maior parte dos pontos com alta sensibilidade, merece alguma estratégia que retarde ou mesmo cesse o processo de conversão da floresta para pastagem ou agricultura. Com relação ao padrão de fragmentação dos remanescentes vegetais, conclui-se o seguinte: os remanescentes de cerrado e floresta, no intervalo de dezoito anos, ficaram menores, mais irregulares, mais distantes e mais numerosos, indicando uma piora no estado de conservação da paisagem entre 1986 e 2004. Isso compromete a manutenção da biodiversidade, a persistência de espécies, diminuindo suas populações mínimas viáveis. A diversificação das formas de uso das terras na matriz é recomendada, com a introdução da silvicultura (principalmente composta por espécies nativas), por exemplo, também poderá auxiliar na manutenção/surgimento da heterogeneidade espacial e da complexidade estrutural da paisagem. A Teoria dos Grafos, avaliada neste trabalho, apresentou-se como ferramenta eficiente para se calcular a conectividade em paisagens heterogêneas. / The research approached the process of use and occupation of lands in the cities of Bonito, Bodoquena and Jardim, situated in the edge east of the National Park of the Serra da Bodoquena (NPSB), southwestern region of Mato Grosso do Sul, Brazil. Moreover, the conservation state was studied, in terms of structure and configuration of the landscape, of the contained remainders of cerrado and forest in the interior of the NPSB and its buffer zone. The objective was to analyze the dynamics of occupation of lands in the cities mentioned in last the 18 years, with sights to subsidizing strategies of planning of the use and ideal occupation for the region. Also, it was objectified to analyze the space-temporal dynamics of the landscape that composes the PNSB and its buffer zone, aiming at to the conservation of local biodiversity. For this, geographic information system (GIS) for the classification of images of satellite and elaboration of thematic maps was used. The determination of the NPSB conservation degree and its buffer zone occurred by means of the use and of metrics of landscape ecology and the adoption of Graph Theory. Chapter 1 demonstrated, by the maps generated for the cities of Bonito, Bodoquena and Jardim, of the years of 1986 and 2004, that it occurred a loss of native area and a consequent growth of the composed matrix for pastures (mainly) and agriculture. Only in Bodoquena the vegetal remainders had percentual had been bigger than the areas of pastures and agriculture. It can be observed that the studied region passes for a process of conversion of natural habitats, long ago continuous, for a composed landscape for patches of cerrado and forests in a matrix predominantly represented by planted pasture and agriculture. Chapter 2 showed that the forest and cerrado physiognomy, had been presented in better conservation in 1986 that in 2004. Moreover, it was possible to observe that the remainders of the vegetal formations above cited, had been presented in better conservation in the interior of the NPSB, that in its buffer zone. The map of relevance of the remainders of forest, considering the agreed area and shape notes metric of the spots, had indicated which the priority areas to be protecting, for possessing characteristics adjusted for the persistence of present forest biodiversity in the NPSB and its buffer zone. The north sector had detached for presenting remainders with high and extremely high values to the relevance. The same north sector posses a bigger number of points of sensitivity to the break of connectivity between the forest spots. In this region it can be observed that most of the points with high sensitivity deserves some strategy that delays or stop the conversion process of the forest for pasture or agriculture. Regard the standard of spelling of the vegetal remainders, had been concluded that: the remainders of cerrado and forest, in the interval of eighteen years, had been lesser, more irregular, more distant and more numerous, indicating a worsening in the state of conservation of the landscape between 1986 and 2004. This compromises the maintenance of biodiversity, the species persistence, diminishing its viable minimum populations. The diversification of the forms of use of lands in the matrix is recommended, with the introduction of forestry (mainly composed for native species), for example, also it will be able to assist in the maintenance/sprouting of the space heterogeneity and the structural complexity of the landscape. The Graph Theory, evaluated in this work, was presented as efficient tool to calculate the connectivity in heterogeneous landscapes.
57

以景觀指數探討台北都會區綠地變遷趨勢之研究 / A study using landscape metrics to investigate the green space change trend in Taipei metropolitan area

蔡杰廷, Tsai, Chieh Ting Unknown Date (has links)
永續發展的概念現今已被運用於都市,其中,都市綠地在環境、生態、景觀、社會各層面之機能皆可提升都市永續性,在快速的都市化下,都市內綠地減少,土地利用變遷帶來之環境衝擊影響已自個體單元累積到全球。然而,過去研究中未有關注在綠地的變化趨勢與其他土地利用間的互動關係,以及在不同區域下的變化差異。因此,本研究採用GIS和景觀指數看在1995年至2006年間台北都會區綠地變遷趨勢,並分區探討土地利用間的互動關係,最後藉由二元羅吉斯迴歸分析綠地變化可能原因。 研究結果顯示,在1995年至2006年間,台北都會區整體發展是建地增加,林地也呈上升趨勢,而草地是土地利用轉移下被犧牲掉最多的土地,綠地轉移成其他土地利用情形以都會邊緣地區最嚴重。不同綠地型態在1995年至2006年間的變遷仍有差異,林地在整個台北都會區屬於景觀中的基質,主導性未受動搖,僅在都會中心減少並受破壞;而農地面積略微下降,呈破碎化發展,尤其以都會中心外圍區農地被破壞情形最明顯;草地面積亦下降,破碎化情形較農地更嚴重,在都會郊區、次中心之草地被破壞嚴重,草地各方面機能降低。透過二元羅吉斯迴歸分析發現自然環境、社會經濟與計畫環境皆影響台北都會區的綠地變遷。根據研究結果,建議未來政府於都市計畫上應將綠地空間納入考量,對於不同綠地型態應有不同管制措施,考量各區域綠地型態之差異性,以及自然環境、社會經濟和計畫環境對於綠地變遷的影響,以促進都市朝向永續發展。 / The concept of sustainable development has been applied in cities. Urban green space plays an important role in enhancing the sustainability of the city in regards to the environment, ecology, landscape and society aspects. Under rapid urbanization, green space has greatly declined in cities. Environmental impact resulting from land use change has grown from local to global proportions. However, researches did not pay attention to interactions between green spaces and other land-use change trends or different types of change in different areas. This research used GIS and landscape metrics to investigate the green space change trend and interactions among different land use types in the Taipei metropolitan area from 1995 to 2006. Furthermore, this research analyzed possible reasons that may have caused green space change through logistic regression. The results showed that, from 1995 to 2006, the built up area and the forest increased in Taipei Metropolitan Area; however, the grass decreased because of land use change. Urban fringe was the place that green space changed to other land-use most. There were differences of land use change for different types of green space. Forest was the matrix in the landscape of Taipei metropolitan area. It still kept the predominant role, only decreased and was destroyed in the center of metropolitan area. Farmland slightly decreased and became fragmented, especially in the periphery of the urban center. Grassland area decreased and became fragmented much more than farmland. In suburb and sub-center, grassland was destroyed seriously and became less functional. Through binary logistic regression, the study found that natural environment, socio-economic and government planning do have influence on green space changes in the Taipei metropolitan area. According to the result of the study, the recommendation was that government should take green space into consideration when doing urban planning. For different types of green space and different areas, the government needs to have different measures and needs to consider the impact factors of green space change in order to accelerate sustainable development in cities.
58

Ecologia de paisagens de fragmentos de Floresta Ombrófila Mista no Planalto Sul Catarinense / Landscape ecology of Araucaria Forest fragments in South Plateau of Santa Catarina State

Cruz, Aline Pereira 26 February 2016 (has links)
Submitted by Claudia Rocha (claudia.rocha@udesc.br) on 2017-12-08T12:19:49Z No. of bitstreams: 1 PGEF16MA060.pdf: 200273 bytes, checksum: c59f22cc1e5f18c0272f4b828aab3423 (MD5) / Made available in DSpace on 2017-12-08T12:19:50Z (GMT). No. of bitstreams: 1 PGEF16MA060.pdf: 200273 bytes, checksum: c59f22cc1e5f18c0272f4b828aab3423 (MD5) Previous issue date: 2016-02-26 / Capes / This work aimed to evaluate the influence of landscape structure on the floristic-structural organization and the demographics rates of the tree component of Araucaria Forest fragments in South Plateau of Santa Catarina State, in Brazil. Studies of this nature are important to the development of conservation strategies in fragmented landscapes, situation of the study area. Two chapters are presented, in the first i) the influence of landscape structure on the floristic-structural patterns in forest fragments was analyzed; and in the second ii) the inter-relationships between the landscape spatial configuration x floristic-structural organization x demographics rates of tree component were verified in a system formed by forest fragments and corridors. For nine forest fragments in the region, surrounding land cover maps and landscape metrics (shape, connectivity and influence of edge) were generated from the Landsat 8 satellite images; and information about floristic-structural composition of tree component was obtained. For the forest fragment-corridor system the demographics rates for a four years period (2010-2014) were also obtained. The data were analyzed through Principal Component Analysis (PCA), Non-Metric Multidimensional Scaling (NMDS), Principal Coordinates Analysis (PCoA), Structural Equations Models, and Generalized Linear Models (GLM). In the first chapter, it was observed that the spatial configuration of the fragments in the landscape (shape complexity and area) and the surrounding land cover (forest, swamp, grassland, urbanization) significantly influenced the floristic-structural organization of the arboreal vegetation. In the second chapter, it was evidenced that the floristic-structural organization of the tree component was influenced by landscape spatial configuration and the tree abundance; and the demographics rates were only influenced by 14 vegetation structure (abundance and basal area). We conclude that the landscape spatial configuration influences the floristic-structural organization in FOM areas and that demographic rates of the tree component are determined primarily by structural aspects, which reflect the successional stage of vegetation / A presente dissertação objetivou avaliar a influência da estrutura da paisagem sobre a organização florística-estrutural e sobre as taxas demográficas do componente arbóreo de fragmentos de Floresta Ombrófila Mista (FOM) no Planalto Sul Catarinense. Estudos dessa natureza são importantes para o desenvolvimento de estratégias de conservação em paisagens fragmentadas, situação em que se encontra a região de estudo. São apresentados dois capítulos, sendo que no primeiro i) foi analisada a influência da estrutura da paisagem sobre os padrões florístico-estruturais em fragmentos florestais; e no segundo ii) foram verificadas as inter-relações entre a configuração espacial da paisagem x organização florística-estrutural x taxas demográficas do componente arbóreo, em um sistema composto por fragmentos e corredores florestais. Para nove remanescentes florestais na região, foram gerados mapas de cobertura do solo no entorno e obtidas as métricas de paisagem de área (forma, conectividade, influência de borda e área das classes de cobertura na vizinhança), a partir de imagens do satélite Landsat 8; e obtidas informações sobre a composição florística-estrutural, além das taxas demográficas do sistema de fragmentos e corredores para um período de quatro anos (2010-2014). Os dados foram analisados por meio de Análise de Componentes Principais (PCA), Escalonamento Multidimensional Não-Métrico (NMDS), Análise de Coordenadas Principais (PCoA), Modelagem de Equações Estruturais e Modelos Lineares Generalizados (GLM). No primeiro capítulo, observou-se que a configuração espacial dos fragmentos na paisagem (complexidade da forma e área) e a cobertura do solo do entorno (floresta, banhado, campo, urbanização) influenciaram de forma significativa a organização florística-estrutural da vegetação arbórea. No segundo capítulo ficou evidenciado que a organização 12 florística-estrutural do componente arbóreo foi influenciada pela configuração espacial da paisagem e pela a abundância de árvores, e as taxas demográficas foram influenciadas apenas por aspectos estruturais (abundância e área basal) da vegetação. Conclui-se que a configuração espacial da paisagem exerce influência sobre a organização florística-estrutural em áreas de FOM e que as taxas demográficas do componente arbóreo são determinadas fundamentalmente por aspectos estruturais, que refletem o estágio sucessional da vegetação
59

Avaliação da cobertura florestal da sub-bacia hidrográfica do rio Alegre, Sul do estado do Espírito Santo, utilizando geotecnologias / Assessment of forest cover in the hydrographic subbasin of the Alegre river, southern Espirito Santo state, using geotechnology

Silva, Kmila Gomes da 12 March 2013 (has links)
Made available in DSpace on 2016-12-23T13:51:55Z (GMT). No. of bitstreams: 1 kmila Gomes da Silva.pdf: 1840290 bytes, checksum: 71792d0ca0267bf6f9206f3a5d471245 (MD5) Previous issue date: 2013-03-12 / The analysis of the plant covering behavior on a temporal scale addresses practices that make forest remnant sustainability possible. The present study seeks to analyze the dynamics of the forest fragments in the hydrographic subbasin of the Alegre river, Espirito Santo state, based on the alterations of the plant covering and the structure of the forest landscape on a space-time scale, through two chapters. The first is based on the hypothesis that vegetation indexes can express similar vegetative or differentiated vigor of canopies of a specific area. To test the hypothesis, the objective was to to compare three vegetation indexes: TVI (Transformed Vegetation Index), CTVI (Corrected Transformed Vegetation Index) and RATIO (Ratio Vegetation Index), in relation to the behavior of NDVI (Normalized Difference Vegetation Index), regarding the discrimination of the vegetative vigor, as well as the alterations in the forest cover between 1987 and 2010. Through the obtained results, it was verified that the vegetation indexes allowed to estimate the vegetative vigor of the plant covering. A 4.90% (NDVI) increase and one of 7.78% (TVI) of forest covering, a pasture reduction of 3.34% (NDVI) and 5.53% (TVI) and a reduction of nonvegetated areas of 5.93% (NDVI) and 3.35% (TVI), in the period between 1987 and 2010 were evidenced. The natural regeneration process might have been the decisive factor for the area increrease and the changes in the forest vegetation of the area. The second chapter was based on the hypotheses that:1) In the forest landscape the predominance of fragments of small area occured during the years studied (1975, 2002 and 2007); 2) there is a predominance of forest fragments with complex forms and with smaller central area; 3) The forest remnants are isolated and with a larger border area. Based on the above, the aim was to characterize the space and temporal evolution of the forest fragment structures using landscape ecology metrics applied in the years of 1975, 2002 and 2007; the structural analysis of the forest fragments was conducted contemplating area parameters, form, nucleus, border and proximity by size classes. Based on the obtained results, a 7% increase was verified in the total area of the forest covering with the appearance of 645 new fragments. The number of fragments increased and the area of contribution small, which implied in the high border/area ratio. The smallest fragments (< 1 ha.) presented simple geometric form in relation to the others. The largest forest fragments (> 20 ha.) were shown proximate, presenting a tendency towards reduction of the proximity measure values / A análise do comportamento da cobertura vegetal numa escala temporal direciona práticas que viabilizam a sustentabilidade dos remanescentes florestais. O presente estudo visa analisar a dinâmica dos fragmentos florestais na sub-bacia hidrográfica do rio Alegre-ES, com base nas alterações da cobertura vegetal e na estrutura da paisagem florestal em uma escala espaço temporal, por meio de dois capítulos. O primeiro deles com base na hipótese de que índices de vegetação podem expressar vigores vegetativos semelhantes ou diferenciados, de dosséis de uma determinada região. Para testar a hipótese, objetivou-se comparar três índices de vegetação: TVI (Transformed Vegetation Index), CTVI (Corrected Transformed Vegetation Index) e RATIO (Ratio Vegetation Index), em relação ao comportamento do NDVI (Normalized Difference Vegetation Índex), quanto à discriminação do vigor vegetativo, bem como as alterações na cobertura florestal entre 1987 e 2010. Por meio dos resultados obtidos, verificou-se que os índices de vegetação permitiram estimar o vigor vegetativo da cobertura vegetal. Evidenciou-se o aumento da cobertura florestal de 4,90% (NDVI) e 7,78% (TVI), redução de pastagens de 3,34% (NDVI) e 5,53% (TVI), e redução de áreas não vegetadas de 5,93% (NDVI) e 3,35% (TVI), entre o período de 1987 e 2010. O processo de regeneração natural pode ter sido o fator determinante para o incremento de área e as mudanças na vegetação florestal da região. Já o segundo capítulo, baseou-se nas hipóteses de que: 1) Na paisagem florestal ocorre a predominância de fragmentos de pequena área durante os anos estudados (1975, 2002 e 2007); 2) Há predominância de fragmentos florestais com formas complexas e com menor área central; 3) Os remanescentes florestais estão isolados e com maior área de borda. Diante disso, objetivou-se caracterizar a evolução espacial e temporal das estruturas dos fragmentos florestais, utilizando as métricas da ecologia da paisagem aplicadas nos anos de 1975, 2002 e 2007; a análise estrutural dos fragmentos florestais foi realizada contemplando parâmetros de área, forma, núcleo, borda e proximidade em classes de tamanho. Com base nos resultados obtidos, verificou-se um aumento de 7% na área total da cobertura florestal com o surgimento de 645 novos fragmentos. O número de fragmentos foi elevado e a área de contribuição pequena, o que implicou na alta relação de borda/área. Os menores fragmentos (< 1 ha) apresentaram forma geométrica simples, em relação aos demais. Os maiores fragmentos florestais ( > 20 ha) mostraram-se próximos, apresentando uma tendência de redução nos valores da métrica de proximidade
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Dinâmica de uso das terras nos municípios de Bonito, Jardim e Bodoquena (MS) e o estado e conservação dos recursos biológicos do Parque Nacional da Serra da Bodoquena e de sua zona de amortecimento / Spatial and temporal dynamics of land use in Bonito, Jardim and Bodoquena (MS) Municipalities, and the conservation state of the biological resources in the Serra da Bodoquena National Park buffer zone

Normandes Matos da Silva 31 March 2008 (has links)
A pesquisa abordou o processo de uso e ocupação das terras nos municípios de Bodoquena, Bonito e Jardim, situados na borda leste do Parque Nacional da Serra da Bodoquena (PNSB), região sudoeste de Mato Grosso do Sul. Além disso, foi estudado o estado de conservação, em termos de estrutura e configuração da paisagem, dos remanescentes de cerrado e floresta contidos no interior do PNSB e em sua zona de amortecimento. O objetivo foi o de analisar a dinâmica de ocupaçao das terras nos municípios mencionados nos últimos 18 anos, com vistas à subsidiar estratégias de planejamento do uso e ocupação das terras ideal para a região. Objetivou-se também analisar a dinâmica espacial e temporal da paisagem que compõe o PNSB e sua zona de amortecimento, visando à conservação da biodiversidade local. Para isso, foi utilizado um sistema de informação geográfica (SIG) para elaboração de mapas temáticos e de um banco de dados georreferenciado. A determinação do grau de conservação do PNSB e da sua zona de amortecimento se deu mediante a utilização de métricas de paisagem, e da adoção dos preceitos da Teoria dos Grafos. O capítulo 1 demonstrou, por meio dos mapas gerados para os municípios de Bodoquena, Jardim e Bonito, dos anos de 1986 e 2004, que ocorreu uma perda de área nativa e um conseqüente crescimento da matriz antrópica composta por pastagens (principalmente) e culturas agrícolas. Apenas em Bodoquena os remanescentes vegetais tiveram maior porcentual que as áreas de pastagens e lavouras. Pode-se observar que a região estudada, passa por um processo de conversão de habitats naturais, outrora contínuos, para uma paisagem composta por fragmentos de cerrados, campos e florestas. O capítulo 2 mostrou que as fisionomias florestais e de cerrado, apresentaram-se em melhor estado de conservação em 1986 que em 2004. Além disso, foi possível observar que os remanescentes das formações vegetais acima citadas, apresentaram-se em melhor estado de conservação no interior do PNSB, que em sua zona de amortecimento. O mapa de relevância dos remanescentes de floresta, considerando as notas combinadas das métricas de forma e área das manchas indicou, quais são as áreas prioritárias para serem protegidas, por possuírem características adequadas para a persistência da biodiversidade florestal presente no PNSB e em sua zona de amortecimento. O setor norte se destacou por apresentar remanescentes com valores alto e extremamente alto com relação à relevância. O mesmo setor norte possui um maior número de pontos de sensibilidade à quebra de conectividade entre as manchas de floresta. Nesta região pode-se observar que a maior parte dos pontos com alta sensibilidade, merece alguma estratégia que retarde ou mesmo cesse o processo de conversão da floresta para pastagem ou agricultura. Com relação ao padrão de fragmentação dos remanescentes vegetais, conclui-se o seguinte: os remanescentes de cerrado e floresta, no intervalo de dezoito anos, ficaram menores, mais irregulares, mais distantes e mais numerosos, indicando uma piora no estado de conservação da paisagem entre 1986 e 2004. Isso compromete a manutenção da biodiversidade, a persistência de espécies, diminuindo suas populações mínimas viáveis. A diversificação das formas de uso das terras na matriz é recomendada, com a introdução da silvicultura (principalmente composta por espécies nativas), por exemplo, também poderá auxiliar na manutenção/surgimento da heterogeneidade espacial e da complexidade estrutural da paisagem. A Teoria dos Grafos, avaliada neste trabalho, apresentou-se como ferramenta eficiente para se calcular a conectividade em paisagens heterogêneas. / The research approached the process of use and occupation of lands in the cities of Bonito, Bodoquena and Jardim, situated in the edge east of the National Park of the Serra da Bodoquena (NPSB), southwestern region of Mato Grosso do Sul, Brazil. Moreover, the conservation state was studied, in terms of structure and configuration of the landscape, of the contained remainders of cerrado and forest in the interior of the NPSB and its buffer zone. The objective was to analyze the dynamics of occupation of lands in the cities mentioned in last the 18 years, with sights to subsidizing strategies of planning of the use and ideal occupation for the region. Also, it was objectified to analyze the space-temporal dynamics of the landscape that composes the PNSB and its buffer zone, aiming at to the conservation of local biodiversity. For this, geographic information system (GIS) for the classification of images of satellite and elaboration of thematic maps was used. The determination of the NPSB conservation degree and its buffer zone occurred by means of the use and of metrics of landscape ecology and the adoption of Graph Theory. Chapter 1 demonstrated, by the maps generated for the cities of Bonito, Bodoquena and Jardim, of the years of 1986 and 2004, that it occurred a loss of native area and a consequent growth of the composed matrix for pastures (mainly) and agriculture. Only in Bodoquena the vegetal remainders had percentual had been bigger than the areas of pastures and agriculture. It can be observed that the studied region passes for a process of conversion of natural habitats, long ago continuous, for a composed landscape for patches of cerrado and forests in a matrix predominantly represented by planted pasture and agriculture. Chapter 2 showed that the forest and cerrado physiognomy, had been presented in better conservation in 1986 that in 2004. Moreover, it was possible to observe that the remainders of the vegetal formations above cited, had been presented in better conservation in the interior of the NPSB, that in its buffer zone. The map of relevance of the remainders of forest, considering the agreed area and shape notes metric of the spots, had indicated which the priority areas to be protecting, for possessing characteristics adjusted for the persistence of present forest biodiversity in the NPSB and its buffer zone. The north sector had detached for presenting remainders with high and extremely high values to the relevance. The same north sector posses a bigger number of points of sensitivity to the break of connectivity between the forest spots. In this region it can be observed that most of the points with high sensitivity deserves some strategy that delays or stop the conversion process of the forest for pasture or agriculture. Regard the standard of spelling of the vegetal remainders, had been concluded that: the remainders of cerrado and forest, in the interval of eighteen years, had been lesser, more irregular, more distant and more numerous, indicating a worsening in the state of conservation of the landscape between 1986 and 2004. This compromises the maintenance of biodiversity, the species persistence, diminishing its viable minimum populations. The diversification of the forms of use of lands in the matrix is recommended, with the introduction of forestry (mainly composed for native species), for example, also it will be able to assist in the maintenance/sprouting of the space heterogeneity and the structural complexity of the landscape. The Graph Theory, evaluated in this work, was presented as efficient tool to calculate the connectivity in heterogeneous landscapes.

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