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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.
21

Protected Area Site Selection Based On Abiotic Data: How Reliable Is It?

Kaya Ozdemirel, Banu 01 February 2011 (has links) (PDF)
Protected area site selection is generally carried out using biodiversity data as surrogates. However, reliable and complete biodiversity data is rarely available due to limited resources, time and equipment. Instead of drawing on inadequate biodiversity data, an alternative is to use environmental diversity (ED) as a surrogate in conservation planning. However, there are few studies that use environmental diversity for site selection or that evaluates its efficiency / unfortunately, no such example exists for Turkey, where biodiversity is high but our knowledge about it is unsatisfactory. Hence, this study was carried out to investigate the efficiency of environmental surrogates and the utility of different biological taxa in conservation planning. The objective was to find out the most efficient surrogates, either environmental or biological, for conservation planning, so that limited resources can be used more efficiently to establish an effective protected areas network. The study was carried out in northeastern Turkey, within the Lesser Caucasus ecoregion. The taxonomic groups considered include large mammals, breeding birds, globally threatened reptiles and amphibians, butterflies, highly threatened plants, and ecological communities. The distribution data was taken from a previous study, while climate and topographical data were obtained from various sources and produced through spatio-statistical techniques. Complementarity-based site selection was carried out with Marxan software, where the planning unit was the 100 sq.km. UTM grid square. Various statistical methods, including geographically weighted regression, principal components analysis, and p-median algorithm, were used to determine ED across the units. Performance of different approaches and different sets of surrogates were tested by comparing them to a random null model as well as representation success. Results indicate that endemic or non-endemic highly threatened plant species, butterfly species and ecological communities represent biodiversity better than other taxa in the study area. As such, they can be used on their own as efficient biodiversity surrogates in conservation area planning. Another finding is that highly threatened plant species are required to be used in the site selection process if they need to be represented well / in other words, they are their own surrogates. It was demonstrated that while ED alone can be used as a surrogate to represent biodiversity of an area, they are not as good as biodiversity surrogates themselves. It is also suggested that using species taxa with smaller distributional ranges or taxa that complement each other due to ecological differences as surrogates provide better results. On the other hand, ED might be a more suitable surrogate if resources are very limited or field work is impossible. In such cases, using ED in conjunction with one of the better biodiversity surrogates is probably the best solution.
22

Dinâmica da paisagem no geossistema do estuário do Rio Paraíba - extremo oriental das Américas: estimativas de perdas de habitat e cenários de recuperação da biodiversidade / Spatial Analisis for biodiversity conservation at the Paraíba River Estuary Geossistema

Stevens, Pamela Oliveira 12 February 2014 (has links)
Made available in DSpace on 2015-05-14T12:17:12Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 5064930 bytes, checksum: 247e078f9d93df87f7340f0cb0801116 (MD5) Previous issue date: 2014-02-12 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The conservation of the biodiversity is intimately dependent on the human appreciation of the facts relating to the changes in usage of the area. The scale of the details of this study defines the size of the geossistemas which are areas determined by a relative uniformity of physical characteristics. A 62.143 hectares geossistema were defined around the Paraiba river estuary and this area was studied with a view of conservation of the biodiversity. The Paraiba river estuary geossistemas is located within the Atlantic Forest area which is one of the world s most biodiverse systems and, as it happens, one of the most degraded. The area studied was given, by the Portaria No 9/2007 of the Ministry of the Environment, a high priority for the conservation of the biodiversity in nine categories, and is one of the most populated areas of the Paraiba state, and one which retains important vestiges of the Atlantic Forest and its associated ecosystems. For the analysis of the changes which led to the loss of the biodiversity of the geossistema, were employed Geographic Information Systems (GIS) techniques, remote sensing and landscape ecology. The use of the land was mapped for two historic dates, 1970 and 2010, and through the interpretation of metrics of landscape ecology it was possible to learn the high degree of vulnerability of the natural environment in the studied area. It was discovered that more than two thirds of the natural vegetation was substituted for human land uses. On the left bank of the river Paraiba estuary the increase of the coconut and sugar cane monocultures and on the right bank the increase of the urban areas of João Pessoa, Cabedelo, Bayeux and Santa Rita have transformed the countryside over the last 36 years. The geossistema landscape was characterized by different types of vegetation mosaic with mean patch size of 70 hectares. Actually the fragments of vegetation have become only small patches distributed mainly in protected areas around the ditches, with mean patch area of 50 hectares. The conservation of the remaining vegetation will be compromised if the connections between the fragments are not re-established. Thus it is important to identify not only priority areas for conservation but also areas suitable for the reestablishment of communication between the fragments. In this treatise the method of Systematic Conservation Planning was used to create scenarios to select the areas which are most in need of forest recovery action. / A conservação da biodiversidade está intimamente ligada ao estudo das transformações do espaço a uma escala adequada à compreensão humana dos fatos. Esta escala caracteriza a dimensão dos geossistemas, que são áreas delimitadas segundo uma relativa uniformidade de aspectos físicos. Foi identificado um geossistema com uma área de 62.143 hectares no entorno do estuário do rio Paraíba PB e o mesmo foi estudado a partir da perspectiva da conservação dos ambientes naturais. O geossistema do estuário do rio Paraíba está localizado no domínio da Mata Atlântica, um dos biomas mais biodiversos do mundo, e, no entanto, também um dos mais degradados. A área de estudo foi considerada prioritária para a conservação da biodiversidade pela Portaria Nº 9/2007 do Ministério do Meio Ambiente (MMA) em nove categorias, e é uma das regiões mais populosas do Estado da Paraíba, e que resguarda importantes remanescentes de vegetação de Mata Atlântica Setentrional e ecossistemas associados. Para a análise das transformações que levaram a perda da biodiversidade no geossistema, foram empregadas técnicas de geoprocessamento, sensoriamento remoto e ecologia da paisagem. além disto, foi testada a metodologia do Planejamento Sistemático da Conservação aplicado na elaboração de cenários que indiquem as áreas mais prioritárias para o estabelecimento de ações de recuperação ambiental. O uso do solo foi mapeado em dois momentos históricos, 1970 e 2010 e através da interpretação das métricas de ecologia da paisagem foi possível compreender o alto grau de vulnerabilidade dos ambientes naturais da área estudada. Foi detectado que mais de dois terços da vegetação natural foi substituída por ocupações humanas apenas no período estudado. Na margem esquerda do estuário do rio Paraíba a ampliação de monoculturas de coco e cana-de-açúcar, e na margem direita, o crescimento das áreas urbanas dos municípios de João Pessoa, Cabedelo, Bayeux e Santa Rita transformaram a paisagem do geossistema. A paisagem do geossistema era caracterizada por um mosaico de tipos diferentes de vegetação com média de tamanho dos fragmentos de 70 ha. Atualmente, os fragmentos de vegetação resumem-se a pequenas manchas distribuídas principalmente em unidades de conservação e ao redor dos corpos d água e a média do tamanho dos fragmentos aproxima-se a 50 ha. A conservação dos remanescentes vegetacionais estará comprometida caso não seja restabelecida a conectividade entre os fragmentos. Desta forma é importante que se identifiquem áreas que sejam prioritárias não apenas para a conservação, mas também áreas adequadas ao estabelecimento de medidas que melhorem a comunicação entre os fragmentos, como a recuperação florestal.
23

From Passive to Active Community Conservation: A Study of Forest Governance in a Region of the Sierra Norte of Oaxaca, Mexico

Van Vleet, Eric 25 March 2013 (has links)
This thesis investigates how seven communities in a subregion of the Sierra Norte of Oaxaca are conserving high forest cover in the absence of national protected areas. To conduct this study I relied on archival research and the review of community documents, focus group interviews and land use transects to explore historical and current land use. I found that communities have conserved 88.34% of the subregion as forest cover, or 58,596 hectares out of a total territory of 66,264 hectares. Analysis suggests that the communities have undergone a historical transition from more passive conservation to more active, conscious conservation particularly in the last decade. This thesis further contends that communities deserve additional financial compensation for this active conservation of globally important forests for biodiversity conservation and that exercises in systematic conservation planning ignore the reality that existing biodiversity conservation in the subregion is associated with community ownership.
24

Dinámica del uso del suelo y cambio climático en la planeación sistemática para la conservación : un caso de estudio en la cuenca Grijalva-Usumacinta / Dynamique de changement d'occupation et d'usage du sol et de changement climatique dans la planification systématique de la protection : un cas d'étude du bassin de réception Grijalva-Usumacinta (Mexique) / Dynamics of land use and cover change and climate change in systematic conservation planning : a case study in the Grijalva-Usumacinta basin (Mexico)

Kolb, Mélanie 22 May 2013 (has links)
Dans les régions néo-tropicales, l’augmentation des taux de changements d’occupation et d’usages des sols et une forte déforestation durant la deuxième moitié du 20e siècle ont engendré une forte dégradation de l’environnement et une forte perte de biodiversité. Cette étude analyse les empreintes spatiales et les processus des changements d’occupation et d’usages des sols et de la déforestation pour le bassin versant du Grijalva-Usumacinta, l’un des plus importants du sud Mexique en matière hydrologique et de biodiversité, pour être confrontée aux discussions sur les changements forestiers émergents. Des cartes d’occupation et d’usages des sols de 1992, 2002 et 2007, dérivées d’images satellitaires et de photographies aériennes sont utilisées pour tester l’hypothèse d’un changement de trajectoires d’évolution à l’échelle régionale. Les probabilités et taux de changements ont été calculés pour les deux périodes 1992-2002 et 2002-2007, et les processus de changements dominants ont été identifiés. Les changements d’occupation et d’usages des sols sont complexes et ne peuvent s’expliquer par une histoire prédominante et linéaire de la déforestation. Deux des principaux résultats concernent (1) un taux anormalement élevé de dégradation des forêts primaires, équivalent à 1,7 fois la surface déforestée ; (2) les processus de déforestation se produisent principalement dans les forêts secondaires. Les activités agricoles, encouragées par les politiques publiques, sont les principaux moteurs de ces changements, parmi lesquelles le pâturage a le plus d'impact sur la déforestation. Les probabilités et taux de déforestation et de changement d’occupation et d’usages de sols ont stagné alors que la reforestation naturelle a augmenté. Bien que ces tendances sont essentielles pour le commencement de la transition forestière, la déforestation et la dégradation l'emportent bien sur la repousse de la végétation. / This study explores how to use techniques of prospective analysis in order to incorporate dynamic factors that put into risk the persistence of biodiversity into systematic conservation planning. Land use and cover change (LUCC) and climate change (CC) represent the main impacts and future threats to biodiversity and thus were the subject of analyses that provided information on prioritization for conservation actions. Since LUCC, CC and biodiversity loss, as well as the related socio-economic structures take place on a regional scale, this work is based on a large watershed in southern Mexico, the Grijalva-Usumacinta Basin. This basin is not only one of the most important areas for biological diversity, but is also renowned for its cultural complexity and hydrological importance and the multiple environmental and social problems that put biodiversity in peril. The main finding is that deforestation and forest degradation are the main LUCC processes and their high rates and strong future trends make it difficult to get to the point of forest transition in the near future, when deforestation and regeneration are balanced. Nevertheless, the scenario analysis shows that it is possible to influence LUCC trajectories in a substantial way in order to halt negative effects over biodiversity in the next decade. CC represents an additional threat to biodiversity difficult to evaluate, especially if the multiple synergistic effects between CC and LUCC are considered that could lead to much higher impacts. Anyway, the analysis showed that even until 2030 CC could have impacts on bioclimatic variables and species composition that could further hamper conservation efforts in the study area. Criteria for a proactive prioritization of sites for conservation are proposed based on scenarios of LUCC and CC. These criteria are used to identify “hot spots” (high probability of LUCC and severe CC impacts) and “refuges” (high probability of permanence and minor CC impacts). This joint analysis of CCUS and CC shows that there are differences between the conservation and the probable scenario; the effort needed to conserve the biodiversity contained in the priority sites in the conservation scenario is considerable less. The spatial pattern of hot spots and refuges of change is very similar across scenarios, despite the differences in absolute areas compromised by each. / Este estudio explora cómo aplicar técnicas de análisis prospectivos para incorporar factores dinámicos que ponen en riesgo la persistencia de biodiversidad en la planeación sistemática de la conservación (PSC). El cambio de cobertura y uso del suelo (CCUS) y el cambio climático (CC) representan los impactos y amenazas futuras más importantes para la biodiversidad, por lo que fueron escogidos como sujetos de análisis que proveen información para la priorización para acciones de conservación. Como el CCUS, el CC, la pérdida de biodiversidad, así como las estructuras socio-económicas relacionadas, ocurren a una escala regional, este trabajo está basado en una cuenca grande en el sur de México. La cuenca Grijalva-Usumacinta no sólo es una de las áreas más biodiversas en el mundo, también es reconocida por su complejidad cultural y su importancia hidrológica. A la vez se han documentado diversos problemas ambientales y sociales que ponen en peligro la persistencia de la biodiversidad. El resultado principal es que la deforestación y la degradación forestal son los procesos dominantes de CCUS y sus altas tasas y fuertes tendencias hacia el futuro vuelven difícil de llegar al punto de la transición forestal, en el cual la deforestación y la regeneración son balanceadas. Sin embargo, el análisis de escenarios muestra que es posible influenciar las trayectorias de CCUS de manera sustancial para detener los efectos adversos en la biodiversidad en la próxima década. El CC representa una amenaza adicional para la biodiversidad difícil de evaluar, especialmente si se consideran los múltiples efectos sinérgicos entre el CC y el CCUS que podrían hacer que el impacto sea mucho mayor. Aun así, el análisis mostró que hasta el 2030 el CC podría tener impactos en las variables bioclimáticas y la composición de especies que podrían dificultar más los esfuerzos de conservación en el área de estudio. Se proponen criterios para una priorización proactiva de la conservación son propuestos basados en escenarios de CCUS y CC. Estos criterios son usados para identificar focos rojos (alta probabilidad de CCUS e impactos de CC severos) y refugios (alta probabilidad de permanencia natural e impactos de CC menores). Este análisis conjunto de CCUS y CC muestra que hay diferencias entre el escenario de conservación y el escenario probable; el esfuerzo necesario para conservar la biodiversidad dentro de los sitios prioritarios es considerablemente menor. Los patrones espaciales de los focos rojos de cambio y los refugios son muy similares en los dos escenarios, a pesar de la diferencia absoluta de áreas en cada uno.
25

A molecular genetic appraisal of biodiversity and conservation units in freshwater fishes from southern Australia.

Hammer, Michael January 2008 (has links)
The freshwater fish fauna of southern Australia is characterised by low species richness and high endemism in groups displaying southern temperate, temperate-subtropical or temperate-tropical distributions. Comparatively few studies in Australia have incorporated modern molecular techniques to delineate species boundaries and define within-species conservation units. This is problematic because freshwater fishes are likely to show high levels of cryptic speciation and marked spatial sub-structure, and is information which is needed to conserve biological diversity and maintain the integrity of ecological communities and processes. The current study uses a ‘combined evidence’ approach, led principally by a set of nuclear genetic markers (allozymes), to assess species boundaries, spatial sub-structure and conservation units in obligate freshwater fishes from southern Australia. A literature review (Chapter 2) concerns the nature and effects of fragmentation in freshwater environments. It considers the implications for freshwater fishes and the types of extrinsic and intrinsic characteristics, both natural and human accelerated, that might drive population fragmentation and divergence. This theoretical framework is then applied to a suite of six largely co-occurring species groups with contrasting biological characteristics, and derive hypotheses about expected levels of genetic divergence across and within different drainages. Major findings Species of Retropinna (Chapter 3) are widespread and generally regarded as ‘common’ and mobile. Allozyme analyses revealed species-level and population-level sub-divisions, including five distinct species with contiguous ranges and no evidence of genetic exchange. Three occur along the eastern seaboard (including three instances of sympatry), another in coastal and inland southeastern Australia and Tasmania, and a fifth in the Lake Eyre Basin. There is no indication of a simple ‘tasmanica’ versus ‘semoni’ dichotomy, but instead a complex pattern involving discrete clusters for the Upper Murray plus Darling rivers, Lower Murray, Glenelg River and Tasmanian regions. These findings have implications for biodiversity, conservation and ecology. This chapter has been published in modified form (Marine and Freshwater Research 58, 327- 341). Nannoperca obscura (Chapter 4) is a small demersal fish with specialised habitat requirements. It is under threat of extinction, particularly in the western section of its range. Combined nuclear and matrilineal genetic data identified congruent within-species sub-structure, divided by patternsof distribution and biogeography. Four monophyletic mtDNA lineages, each distinct at multiple nuclear loci, indicate four Evolutionarily Significant Units (ESUs), namely (1) Lake Alexandrina in the Murray-Darling Basin (MDB), (2) Glenelg River, Millicent Coast River Basin and the outlying Mt Emu Creek, (3) Merri River and associated coastal streams, and (4) the eastern range section. Additional genetic and ecological data support multiple Management Units (MUs) within ESUs for individual or groups of river basins separated by marine barriers. Nannoperca australis (Chapter 5) has a similar character to its aforementioned congener, except that it occurs across a much wider area. Although generally common, particular populations are threatened, especially in the MDB. Allozyme analyses of 57 populations confirm the presence of two divergent species, with an eastern species containing two ESUs: (1) Gippsland and Flinders Island, and (2) Ansons River in northeastern Tasmania. The western species shows sub-structure across its range, including a separation of MDB and coastal populations as two heterogenous ESUs. The Lower Murray region (Mount Lofty Range streams and the Lower Lakes) harbours a remarkable level of between- and within-population diversity, underscoring its importance for conserving evolutionary potential. Mogurnda adspersa (Chapter 6) has been presumed extinct in South Australia since the early 1970s and has also been assumed lost from the southern MDB. This chapter reports on the rediscovery of M. adspersa from a wetland near the terminus of the Lower Murray, some 2500 river kilometres from the nearest known population. The nature and basic ecology of this population is documented, but the combined effects of drought and water abstraction recently have led to the probable extirpation of the wild population. A combined allozyme and mtDNA dataset confirmed the ‘nativeness’ of the population as a distinct sub-population (and MU), with a moderate level of allele heterogeneity. This information provides a platform for captive breeding as a conservation measure. The endemic genus Philypnodon (Chapter 7) contains two nominal species: P. grandiceps and the long recognised but only recently described P. macrostomus. The former is considered widespread and common (near ubiquitous), whereas the latter is more patchily distributed. Some tolerance to marine conditions is indicated, suggesting that there may be less sub-structure, but allozyme analyses of 269 individuals indicate the presence of multiple, species-level taxa within both described species. This obscures interpretations of existing ecological data. Although the presence of genetically-similar populations within and across some drainage divides indicates higher levels of gene flow, the pattern is complex and suggests historic genetic exchange between some but not other geographically-adjacent taxa. The freshwater blackfish genus Gadopsis (Chapter 8) has been a problem group for taxonomists, and it is unclear where the group is placed phylogenetically and how many species occur. Northern and southern forms on respective sides of the Great Dividing Range have been proposed, but with limited supporting evidence. Its dispersal ability (hence predicted genetic structure) is obscured by opposing life-history traits, including large body size (i.e. good swimming ability) versus habitat specialisation, demersal larvae and restricted home ranges. This chapter provides a genetic overview incorporating 61 locations across the range, and demonstrates unequivocally the presence of distinct northern and southern species of G. ‘marmoratus’. Moreover, distinct genetic discontinuities involving geographically abutting lineages indicate the likely presence of multiple ESUs within each species. A comparison of the allozyme data with previous mtDNA studies also identified two ESUs within G. bispinosus. Overall, considerable complexity is demonstrated signalling the need for a review of how the southern Australian fish fauna should be viewed, studied and protected. The genetic data also provide insight into the interplay of intrinsic biological characters (e.g. dispersal ability, population ecology) with historic and contemporary extrinsic environmental factors (e.g. fragmentation, biogeographic processes). Comparisons between and within traditionally-defined species are problematic, however, owing to multiple species-level splits and other genetic divisions that may have matching biological counterparts. Together with other reports in the literature, the findings presented herein have significant conservation implications, particularly given the rapid pace of human-mediated change in some regions that house high species and genetic diversity and unique evolutionary components, notably southeastern Queensland (especially the Mary River) and the lower River Murray in South Australia. Other regions displaying high genetic substructure or divergent populations include the Clarence River and Lachlan River in New South Wales; Gippsland, Goulburn River, Glenelg River and Mt Emu Creek in Victoria, and the Macquarie River and Ansons River in Tasmania. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1339749 / Thesis (Ph.D.) - University of Adelaide, School of Earth and Environmental Sciences, 2008
26

Planejamento para a conservação de plantas ameaçadas no cerrado brasileiro / Conservation planning of threatened plants in the brazilian cerrado

Monteiro, Lara de Macedo 15 March 2017 (has links)
Submitted by Franciele Moreira (francielemoreyra@gmail.com) on 2017-08-17T18:33:27Z No. of bitstreams: 2 Dissertaçao - Lara de Macedo Monteiro - 2017.pdf: 68300760 bytes, checksum: ba7fbce35b9ab3e46180337ae3129580 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2017-08-18T12:02:30Z (GMT) No. of bitstreams: 2 Dissertaçao - Lara de Macedo Monteiro - 2017.pdf: 68300760 bytes, checksum: ba7fbce35b9ab3e46180337ae3129580 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2017-08-18T12:02:30Z (GMT). No. of bitstreams: 2 Dissertaçao - Lara de Macedo Monteiro - 2017.pdf: 68300760 bytes, checksum: ba7fbce35b9ab3e46180337ae3129580 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2017-03-15 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Earth is facing the highest species' extinction rates of its history, and humans are the major stressar. Adding up to this biodiversity crisis, species-rich areas, which also coincide with areas highly transformed by humans (e.g. biodiversity hotspots), are poorly covered by protected areas. ln Brazil this reality is not different. Responsible for harbouring a third of all plant species already classified under a threat category (n= 645), the Brazilian Cerrado has only 8.3% of its area legally protected. ln this biorne, the campos rupestres, a mountaintop grassland ecosystem, stands out for its high number of threatened species currently underrepresented in conservation strategies. ln chapter 1, we aimed at indicating priority areas to secure protection of the threatened plant species from the southern Espinhaço mountains, a region that encampasses large areas of campos rupestres. We found that it is possible to protect, on average, more than 25% of the threatened species' ranges, avoiding sites with extensive use for farming and mining and favouring areas with intensive fire frequency by constraining the management to a relatively small area of only 17% of the region. Conservation plans such as these proposed for campos rupestres represent important opportunities to fulfil the gap existent between research and implementation. However, we do not rule out the need for increasing sophisticated tools that account for the consequences of complex processes threatening biodiversity in the near future ( e.g. clima te change and deforestation) and especially the need for predictive and realistic conservation strategies that anticipate and mitigate their negative effects. Unfortunately, until now we have been relying species protection to a residual system of PAs that provide minimal conservation impact. Thus, in chapter 2 we aimed to select spatial conservation priorites that minimize the risk of deforestation while retaining sites with high plant biodiversity value threatened from climate change in the Brazilian Cerrado. We simulated two ways of spacing out priorities for conservation actions ("time-step action" and "acting now''), and two methods of setting priorities: one that minimizes expected habitat conversion and prioritizes high valuable sites to plant biodiversity at risk from climate change (maximum conservation impact) and another that prioritizes sites based only on their value for plant biodiversity at risk from climate change, regardless their vulnerability to land conversion ("usual approach''). We found that although the scenarios that maximize conservation impact avoided higher amounts of vegetation loss, they prevented least species' range loss. Moreover, the acting now scenarios always performed better in terms of range loss avoided compared to the time-step scenarios under the sarne method of prioritization. Finally, we believe that planning for vegetation loss avoidance is a more conservative strategy because vegetation information is less subjective to any source of bias and is a better surrogate for general biodiversity. We also recommend that acting as soon as possible is always the best strategy to guarantee biodiversity conservation in the Cerrado. / A Terra vem enfrentando as maiores taxas de extinção de espécies de sua história, e os humanos são a maior causa disso. Além da crise de biodiversidade, áreas ricas em espécies, que, por sua vez, coincidem com locais sob alta influência de atividades humanas (ex: hotspots de biodiversidade), são pouco representadas por Unidades de Conservação. No Brasil, essa realidade não é diferente. Responsável por abrigar um terço de todas as espécies de plantas já classificadas sob uma das categorias de ameaça (n=645), o Cerrado brasileiro possui somente 8.3% de sua área legalmente protegida. Nesse biorna, o ecossistema de campos rupestres destaca-se pelo seu alto número de espécies ameaçadas atualmente subrepresentadas em estratégias de conservação. No capítulo 1, nosso objetivo foi indicar áreas prioritárias para assegurar a proteção de espécies ameaçadas de plantas da Serra do Espinhaço Meridional, uma região que abrange grandes trechos de campos rupestres. Nós encontramos que é possível proteger, em média, mais de 25% da distribuição das espécies ameaçadas restringindo o manejo a uma área relativamente pequena de apenas 17% da região e evitando locais de uso extensivo do solo para agropecuária e mineração e favorecendo locais com alta ocorrência de queimadas. Planos de conservação como esse proposto para campos rupestres representam importantes oportunidades para preencher a lacuna existente entre pesquisa e implementação. No entanto, nós não descartamos a necessidade de ferramentas mais sofisticadas que considerem as consequências dos complexos processos que ameaçam a biodiversidade em um futuro próximo ( ex: mudanças climáticas e desmatamento) e, especialmente, a necessidade de estratégias de conservação preditivas e realistas que antecipem e mitiguem seus efeitos negativos. Infelizmente, até agora a proteção das espécies tem se restringido a um sistema residual de unidades de conservação de baixo impacto para a conservação. Portanto, no capítulo 2 nosso objetivo foi selecionar espacialmente locais de alto valor para a biodiversidade de plantas ameaçadas em um cenário de mudanças climáticas e ao mesmo tempo minimizar o risco de conversão da vegetação desses locais. Nós simulamos duas formas de particionar as ações de conservação ("ação em intervalos de tempo" e "agir agora") e dois métodos de estabelecer prioridades: um que minimiza a conversão de hábitat esperada e prioriza locais altamente importantes para a biodiversidade de plantas ameaçadas em um cenário de mudanças climáticas ("máximo impacto da conservação") e outro que prioriza locais baseando-se somente no seu valor para a biodiversidade de plantas ameaçadas em um cenário de mudanças climáticas, independentemente de sua vulnerabilidade ao desmatamento ("abordagem habitual''). Nós encontramos que, embora os cenários que maximizem o impacto da conservação tenham evitado maiores perdas de vegetação, eles evitaram uma menor perda no tamanho médio da distribuição das espécies comparado às abordagens habituais. Além disso, constatamos que os cenários "agir agora" tiveram um melhor desempenho em termos de perda de distribuição evitada comparado aos cenários de implementação sequencial de ações considerando um mesmo método de priorização. Finalmente, nós acreditamos que planejar para evitar perda de vegetação é uma estratégia mais segura, porque a informação sobre vegetação é menos sujeita a qualquer viés e é um melhor indicador para biodiversidade em geral. Também recomendamos que agir o quanto antes é sempre a melhor estratégia para garantir a conservação da biodiversidade no Cerrado.
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Prioridades espaciais para a conservação de mamíferos do Cerrado em um mundo em mudança / Spatial priorities for conservation of mammals from Cerrado in a change world

FALEIRO, Frederico Augusto Martins Valtuille 28 March 2012 (has links)
Made available in DSpace on 2014-07-29T16:21:19Z (GMT). No. of bitstreams: 1 Faleiro Frederico Dissertacao.pdf: 1687158 bytes, checksum: e1a8a44e89beea38d1a839934c890e56 (MD5) Previous issue date: 2012-03-28 / The human actions has triggered many threats to biodiversity like land-use and climate changes, overexploitation, pollution, and introduction of invasive species, which can affect organisms both at local and global scale. The science of spatial conservation prioritization emerged as a quantitative approach to support the spatial decisions in face of these threats, while minimizing the socioeconomic and political conflicts. Here we developed spatial solutions to the conservation of non-flying mammals from Brazilian Cerrado considering the socioeconomic costs and the opportunities of environmental governance (first objective). Further, we generated solutions to face the land-use and climate change taking into account the dispersal abilities of species and uncertainties in the species distribution modeling (SDM) process (second objective). We considered the current network of reserves of the Cerrado in both objectives. We built SDMs for 154 species combining model projections weighted by their statistical fit to produce consensus maps of species distribution grouped in three distinct types of models (envelope, statistical and machine-learning models), for both current future scenarios of climate (used only in the last aim). For the first goal, we used the current predicted distribution to run spatial prioritization analyses indicating the best sites for the conservation investment considering human population density, land cost, anthropogenic land use, level of environmental governance, and the distribution of species in trade-off analyses. For the second goal, we used both current and future predicted distribution to run optimization procedures and propose priority sites for conservation, while minimizing species climate-forced dispersal distance , the mean uncertainty associated to the SDM process, and taking into account the future changes in the landscape (by our land use model). SDMs indicated that species-rich sites converge to regions with high population density, high land cost, high anthropogenic land use, and with diverse levels of environmental governance. There was a significant change in spatial priorities when socioeconomic and political dimensions were included in analyses: top priority sites moved towards the north. This spatial change reduced by 68% the potential conservation conflicts with human population, by 72% the likely conflicts arising from land cost and by 68% anthropogenic land use. It also increased by 51% the beneficial effect of environmental governance. Including land-use changes and the modeling uncertainty in the conservation planning process changed significantly the spatial distribution of priority sites in the region. While the inclusion of land-use models altered the spatial location of priority sites at the regional scale, the effects of climate change tended to take place at the local scale. Note that, our solutions already include possible dispersal corridors linking current and future priority sites for mammal conservation, as well as a formal risk analysis based on planning uncertainties. Our results allowed dealing with both complex nature of conflicts among socioeconomic and political dimensions, and the dynamic problem imposed mainly by land-use and climate change. Thus, our analyses figure as a methodological prospect supporting the decision-make process and the consequent translation of conservation planning outcomes into conservations actions / As ações humanas têm desencadeado diversas ameaças a biodiversidade como as mudanças de uso do solo e do clima, sobre-exploração, poluição e introdução de espécies invasoras, que afetas os organismos da escala local até a global. A ciência da conservação espacial para conservação emergiu como uma abordagem quantitativa que tem o objetivo de auxiliar escolhas espaciais que lidem com essas ameaças enquanto minimizam conflitos socioeconômicos e políticos. Aqui nós desenvolvemos soluções espaciais para conservação de mamíferos não voadores do Cerrado considerando os custos socioeconômicos e as oportunidades vindas da governança ambiental (primeiro objetivo). Além disso, nós geramos soluções espaciais que lidem com as mudanças do uso do solo e climáticas levando em consideração as capacidades de dispersão das espécies e as incertezas associadas ao processo de modelagem de distribuição de espécies (MDE) (segundo objetivo). Em ambos objetivos nós consideramos a atual rede de reservas do Cerrado. Nós modelamos a distribuição de 154 espécies combinando as projeções dos modelos e pesado pelo ajuste estatístico para produzir os mapas consenso de distribuição das espécies, agrupados em três distintos tipos de modelos (modelos de envelope, estatísticos e de inteligência artificial), para a atualidade e projetados para o futuro (usado apenas no último objetivo). Para o primeiro objetivo, nós usamos as predições da atual distribuição das espécies para realizar as análises de priorização espacial, indicando os melhores locais para investimento considerando a densidade humana, custo da terra, uso do solo antropogênico, nível de governança ambiental e a distribuição das espécies na perspectiva da análise de demandas conflitantes. Para o segundo objetivo, nós usamos a distribuição atual e futura das espécies para realizar o procedimento de otimização e propor locais para conservação que minimizem os efeitos da dispersão induzida pelas mudanças climáticas, incertezas associadas ao processo MDE e considerando as futuras mudanças na paisagem (através do nosso modelo de uso do solo). A MDE indicou que locais ricos em espécies convergem para locais com alta densidade populacional, alto custo de terra, alta proporção de uso do solo voltado para atividades humanas e diversos níveis de governança ambiental. Houve significativas mudanças nas prioridades espaciais quando as dimensões socioeconômicas e políticas foram incluídas nas análises, fazendo que os locais prioritários mudassem para o norte. Essa mudança espacial reduziu em 68% de potenciais conflitos com população humana, em 72% de conflitos de custo da terra, em 68% de conflitos com o uso do solo antropogênico e 51% de aumento dos possíveis benefícios da governança ambiental. Quando incluímos as mudanças de uso de solo e a incerteza da modelagem no processo de planejamento, os locais prioritários mudaram significativamente na região. Enquanto a inclusão das mudanças no uso do solo alterou a localização espacial dos locais prioritários em escala regional, os efeitos da mudança climática tenderam a ocorrem em escala local. Note que nossas soluções já incluíram possíveis corredores de dispersão para ligação entre as atuais áreas prioritárias com aquelas importantes no futuro, tão bem quanto a análise de risco baseado nas incertezas do planejamento. Nossos resultados permitiram lidar tanto com a complexa natureza dos conflitos entre dimensões socioeconômicas e políticas quanto com problema dinâmico imposto principalmente pelas mudanças do uso do solo e climáticas. Assim, nossas análises auxiliam metodologicamente a dar suporte no processo de tomada de decisão e a consequente tradução dos resultados de planejamentos de conservação em ações de conservação
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Biogeografia da conservação frente à expansão agrícola: conflitos e prioridades / Conservation Biogeography faced with agricultural expansion: conflicts and priorities

DOBROVOLSKI, Ricardo 10 April 2012 (has links)
Made available in DSpace on 2014-07-29T16:23:34Z (GMT). No. of bitstreams: 1 Tese Ricardo Dobrovolski.pdf: 1981880 bytes, checksum: 8c60352c3d999171ab957f065b32a9db (MD5) Previous issue date: 2012-04-10 / Agriculture is the human activity with the greatest impact on the environment. Specifically, it represents the greatest threat to biodiversity. In the future, this activity should expand due to population growth, increased consumption and production of biofuels from food. To understand the possible impacts of this expansion on biodiversity, we used scenarios of land use change between 1970 and 2100 from IMAGE (Integrated Model to Access Global Environment) to test the following hypotheses: (i) areas considered as global priorities for conservation by international NGOs will be preferentially impacted by agricultural expansion in the XXI century, (ii) there is a conflict between the priority areas for carnivores conservation and agricultural expansion, and this conflict can be reduced by incorporating information on agricultural expansion in the prioritization process, (iii) the integration among countries for conservation planning may benefit both biodiversity and agricultural productivity, (iv) Brazilian protected areas will be impacted by agricultural expansion in the future and this impact will differ between protected areas of integral protection and those of sustainable use. We found that: (i) the impact on priority areas for conservation depends on the criteria by which they were set, so that areas defined by its high vulnerability are currently most affected than those of low vulnerability. Throughout the XXI century this impact is expected to increase, although the difference between the two types of priorities remains, except for High Biodiversity Wilderness Areas, defined by their low vulnerability in current time, but for which most pessimistic scenarios forecast an impact similar to priority areas of high vulnerability, (ii) there is a high spatial congruence between areas with high agricultural use in the future and priority areas for conservation of carnivores. This conflict can be reduced if the prioritization process include information on agricultural expansion; this incorporation, however, causes a profound change in the distribution of priority areas and reduces the number of protected carnivore populations, (iii) the integration of countries to create a set of priority areas for conservation that represents 17% of the land surface can protect 19% more mammal populations without reducing food production, compared to a strategy in which each country seeks to protect its territory independently, and (iv) the impact of agriculture in Brazil is expected to increase until the end of the century, threatening even the protected areas and their surroundings. This impact, however, should not be different between areas of sustainable use and those of integral protection. We conclude that agricultural expansion should remain a major threat to biodiversity in the future, even in areas of special interest for conservation. Conservation actions should be planned taking into account this threat in order to reduce their potential impacts. For this, countries like Brazil should strengthen its surveillance on agricultural expansion and on how this activity is developed. Furthermore, the integration of international conservation efforts should be pursued, given its benefits for biodiversity and food production. Finally, humanity must choose methods of agricultural production that reduce its impacts, including avoiding its future expansion, so as to meet the increasing needs of a human population globally. / A agricultura é a atividade humana com maior impacto sobre o ambiente. Particularmente, ela representa a maior ameaça à biodiversidade. No futuro, essa atividade deve expandir-se com o aumento populacional humano, o aumento do consumo e a produção de biocombustíveis a partir dos alimentos. Para entender os possíveis impactos dessa expansão sobre a biodiversidade, nós utilizamos cenários de mudança de uso do solo entre 2000 e 2100 do IMAGE (Integrated Model to Access Global Environment) para testar as seguintes hipóteses: (i) as áreas consideradas como prioridades globais de conservação pelas ONGs internacionais serão preferencialmente impactadas pela expansão agrícola no século XXI; (ii) há um conflito entre áreas prioritárias para a conservação de carnívoros e a expansão agrícola e esse conflito pode ser reduzido com a incorporação da informação sobre expansão agrícola no processo de priorização; (iii) a integração entre os países para o planejamento da conservação pode ser favorável à proteção da biodiversidade e à produção agrícola; (iv) no Brasil, as áreas protegidas serão impactadas pela expansão agrícola no futuro e esse impacto será diferente entre áreas de proteção integral e áreas de uso sustentável. Nós encontramos os seguintes resultados: (i) o impacto sobre as áreas prioritárias para a conservação depende dos critérios pelos quais elas foram definidas, assim, as áreas definidas por sua alta vulnerabilidade estão atualmente mais impactadas do que áreas de baixa vulnerabilidade. Ao longo do século XXI, o impacto geral da agricultura deve aumentar, mas a diferença entre os dois tipos de prioridades se mantém, exceto para as High Biodiversity Wilderness Areas, definidas por sua baixa vulnerabilidade, mas que nos cenários mais pessimistas podem ter um impacto agrícola semelhante ao das áreas de alta vulnerabilidade; (ii) há uma alta congruência espacial entre áreas com elevado uso agrícola no futuro e áreas prioritárias para a conservação de carnívoros; esse conflito pode ser reduzido se o processo de priorização incluir as informações sobre a expansão agrícola; a incorporação dessa informação, entretanto, provoca uma profunda alteração na distribuição das áreas prioritárias e reduz o número de populações de carnívoros protegidas; (iii) a integração entre os países para a criação de um conjunto de áreas prioritárias para conservação que represente 17% da superfície terrestre pode proteger 19% mais populações de mamíferos sem reduzir a produção de alimentos, se comparada a uma estratégia em que cada país busque proteger seu território independentemente; (iv) o impacto da agricultura no Brasil deve aumentar até o fim do século XXI, ameaçando inclusive as áreas protegidas e o seu entorno. Esse impacto, porém, não deve ser diferente entre as áreas de uso sustentável e aquelas de proteção integral. Assim, a expansão agrícola deve continuar a ser uma importante ameaça à biodiversidade no futuro, atingindo inclusive áreas de especial interesse para a conservação. As ações de conservação devem ser planejadas levando em consideração essa ameaça, a fim de reduzir seus impactos potenciais. Para isso, países como o Brasil devem reforçar sua vigilância sobre a expansão agrícola e a maneira como essa atividade é desenvolvida. Além disso, a integração internacional dos esforços de conservação deve ser buscada, dados seus benefícios para a biodiversidade e para a produção de alimentos. E por fim, a humanidade deve optar por formas de produção agrícola que reduzam seus impactos, inclusive evitando sua expansão futura, mas que possam satisfazer as necessidades da população humana globalmente.

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