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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.
341

Efeito do contexto da paisagem em diferentes escalas sobre a distribuição de pequenos mamíferos em cultivos agrícolas e em remanescentes florestais / Effect of landscape context at different scales on the distribution of small mammals in areas of agriculture and in forest remnants

Fabiana Umetsu 27 October 2010 (has links)
Este estudo enfocou a importância do contexto de ambientes alterados do entorno para a distribuição de diferentes grupos de espécies de pequenos mamíferos não-voadores em paisagens fragmentadas de Mata Atlântica. Na primeira abordagem (capítulo 2), usando a distribuição de pequenos mamíferos em remanescentes florestais e nos quatro principais habitats alterados de uma paisagem de Mata Atlântica, investigamos (1) como o poder explanatório dos modelos que descrevem a distribuição das espécies em fragmentos florestais varia entre as variáveis da estrutura da paisagem que incorporam ou não a qualidade da matriz e (2) a importância da escala espacial para analisar a influência da estrutura da paisagem. Usamos amostragem padronizada nos remanescentes e habitats alterados para gerar dois índices de qualidade de habitat, correspondentes à abundância e à ocorrência de pequenos mamíferos. Para cada remanescente, calculamos a quantidade de habitat e a conectividade em diferentes escalas espaciais, considerando ou não a qualidade dos habitats ao redor. A incorporação da qualidade da matriz aumentou o poder explanatório dos modelos para todas as escalas espaciais para metade das espécies que ocorreram na matriz, mas apenas quando consideramos a distância entre as manchas de habitat (conectividade). Os resultados indicam a importância da matriz para a dinâmica de paisagens fragmentadas e sugere que índices relativamente simples podem melhorar nosso entendimento sobre a distribuição das espécies, e poderiam ser aplicados na modelagem, monitoramento e manejo de paisagens tropicais complexas. Na segunda abordagem (capítulo 3), testamos duas hipóteses relacionadas à importância do contexto da paisagem para a diversidade biológica encontrada em áreas agrícolas usando os pequenos mamíferos da Mata Atlântica como modelo: (1) que o contexto em que cultivos agrícolas estão inseridos, em particular a quantidade de florestas remanescentes, determina a assembléia de pequenos mamíferos encontrada nestas áreas produtivas; (2) que essas respostas ao contexto são escala-dependentes, sendo observadas em escalas espaciais mais amplas. Para tanto, amostramos 36 sítios em áreas agrícolas em duas paisagens fragmentadas de Mata Atlântica com diferentes proporções de florestas nativas remanescentes, os quais foram selecionados de forma a abranger ampla variação na quantidade e agregação de áreas abertas no entorno imediato. Construímos e comparamos 12 modelos candidatos que diferem quanto à contribuição dos efeitos do contexto em escala espacial ampla e em escala local, incluindo todas as combinações possíveis entre essas variáveis, a interação das variáveis medidas em diferentes escalas, e um modelo nulo. De acordo com as expectativas iniciais, as espécies restritas a biomas florestais foram mais comuns e bem distribuídas em áreas agrícolas circundadas por maiores quantidades de floresta em escala ampla. No entanto, as espécies invasoras e não-restritas a biomas florestais dominaram as áreas agrícolas das duas paisagens estudadas, independentemente da quantidade de floresta remanescente em escala ampla, tendo respondido principalmente, mas de maneira oposta, ao contexto em escalas menores. Os resultados indicam que: (1) a resposta diferencial entre os grupos de espécies é condicionada por diferenças nos requerimentos de habitat entre eles; (2) a manutenção de espécies mais exigentes em áreas agrícolas depende de estratégias de manejo que considerem a escala da paisagem; (3) mesmo áreas de agricultura convencional podem ser importantes para a conectividade da paisagem para espécies exigentes, desde que inseridas em contexto de maior quantidade de matas remanescentes; (4) o controle das populações de espécies invasoras que podem atuar como reservatórios de patógenos causadores de doenças no homem e pestes na agricultura depende de manejo em escala local, pelo menos em paisagens onde as áreas agrícolas são predominantes. / This study focused on the importance of the context of altered habitats in the neighborhoods to the distribution of different groups of species of non-flying small mammals in fragmented landscapes of the Atlantic forest. In the first approach (chapter 2), using the distribution of small mammals in forest remnants and in the four main altered habitats in an Atlantic forest landscape, we investigated 1) how explanatory power of models describing species distribution in forest remnants varies between landscape structure variables that do or do not incorporate matrix quality and 2) the importance of spatial scale for analyzing the influence of landscape structure. We used standardized sampling in remnants and altered habitats to generate two indices of habitat quality, corresponding to the abundance and to the occurrence of small mammals. For each remnant, we calculated habitat quantity and connectivity in different spatial scales, considering or not the quality of surrounding habitats. The incorporation of matrix quality increased model explanatory power across all spatial scales for half the species that occurred in the matrix, but only when taking into account the distance between habitat patches (connectivity). Results indicate the importance of the matrix for the dynamics of fragmented landscapes and suggest that relatively simple indices can improve our understanding of species distribution, and could be applied in modeling, monitoring and managing complex tropical landscapes. In the second approach, (chapter 3), we aimed at testing two hypotheses related to the importance of landscape context to the biological diversity found in areas of agriculture using Atlantic forest small mammals as a model: (1) that the context in which the areas of agriculture are inserted, in particular the quantity of remnant forests, determines the assemblage of small mammals found in those productive areas; (2) that those responses to the context are scale-dependent, being observed at larger spatial scales. To accomplish that, we sampled 36 sites in areas of agriculture in two fragmented Atlantic forest landscapes presenting different proportions of native forest remnants, which were selected aiming at including the widest variation in quantity and aggregation of open anthropogenic areas in the local neighborhood. We built and compared 12 candidate models which differed in relation to the contribution of the effects of context at large and local spatial scales, including all possible combinations between these variables, the interaction of the variables measured at different scales, and the null model. According to our initial expectations, the species that are restricted to forest biomes were the commonest and best-distributed ones, in areas of agriculture surrounded by higher quantities of forest at the large scale. However, the invasive species and the species that are not restricted to forest biomes dominated the areas of agriculture in the two studied landscapes, independently from the quantity of remnant forest at the large scale, and they responded mainly, but in the opposite way, to the context at smaller scales. The results indicate that: (1) the differential response between the groups of species is conditioned by differences in habitat requirements between them; (2) the maintenance of more demanding species in agricultural lands depends on management strategies which consider the landscape scale; (3) even areas of conventional agriculture can be important to the connectivity of the landscape for the most demanding species, as far as they are inserted in a context of higher quantities of remnant forest; (4) the control of the populations of invasive species that can act as reservoirs of pathogens that cause disease in men, and that can be pests in agriculture, depends on the management at local scale, at least in landscapes where the areas of agriculture predominate.
342

Pequenos mamíferos terrestres e a regeneração da Mata Atlântica: influência da estrutura do habitat e da disponibilidade de alimento na recuperação da fauna / Terrestrial small mammals and Atlantic forest regeneration: effect of habitat structure and food availability in the wildlife recovery

Bruno Trevizan Pinotti 09 April 2010 (has links)
Através da amostragem de 28 sítios em diferentes estádios de regeneração em uma área de Mata Atlântica contínua, procuramos nesta dissertação contribuir para o entendimento dos mecanismos relacionados às mudanças faunísticas observadas durante o processo de regeneração em florestas tropicais, e, assim, melhor compreender o valor das florestas secundárias para a conservação da biodiversidade tropical. Para isso, na primeira parte da dissertação investigamos a influência da regeneração sobre características de estrutura da floresta e disponibilidade de alimento consideradas importantes para diversos grupos da fauna. Encontramos maior profundidade do folhiço, volume de galhadas e disponibilidade de frutos de uma abundante palmeira de sub-bosque nas florestas mais maduras, enquanto que nas áreas em estádio mais inicial de regeneração encontramos maior conexão da vegetação, biomassa de artrópodes no solo e disponibilidade de frutos no total e da espécie de planta mais abundante no sub-bosque. Essas modificações podem estar relacionadas às mudanças na fauna observadas durante a regeneração florestal. As espécies que dependem de características só encontradas nas matas mais maduras, como espaços abertos para movimentação, maior complexidade do chão da floresta, ou determinados recursos alimentares poderiam encontrar limitações em áreas em estádios mais iniciais de regeneração, ao passo que espécies que não dependem desses recursos poderiam se beneficiar da maior disponibilidade total de alimentos, ou da maior conexão da vegetação para movimentação, encontradas nessas áreas. Na segunda parte do trabalho, avaliamos a influência da regeneração e de características estruturais e de disponibilidade de alimento sobre espécies endêmicas (especialistas de floresta) e não-endêmicas (generalistas de habitat) de pequenos mamíferos terrestres. Como previsto, observamos que um grupo de espécies (generalistas de habitat) prolifera nas áreas mais jovens, enquanto que o outro grupo (especialistas de floresta) foi mais comum, embora de maneira mais sutil, nas áreas mais maduras. Esses padrões foram em parte explicados pelas variáveis mensuradas, principalmente a disponibilidade de recursos alimentares. Aparentemente, as espécies generalistas estão se beneficiando da maior disponibilidade de alimentos encontrada nas áreas em estádio mais inicial de regeneração, enquanto que as especialistas possuem maior capacidade de ocupação das áreas mais maduras, onde esses recursos são mais escassos. Portanto, esses resultados sugerem um compromisso (trade-off) entre capacidade competitiva e capacidade de utilização de recursos 101 abundantes, como prevê o mecanismo de nicho sucessional, proposto inicialmente para explicar a sucessão de espécies vegetais. As características encontradas nas florestas mais jovens favoreceram a proliferação de espécies de pequenos mamíferos terrestres generalistas de habitat. Entretanto, o efeito positivo da regeneração florestal sobre as espécies especialistas, de maior interesse para a conservação, foi menos acentuado, de forma que as florestas secundárias abrigaram uma assembléia de pequenos mamíferos terrestres rica, podendo, portanto, representar um importante instrumento de aumento de área e conectividade em paisagens altamente modificadas, como as encontradas na Mata Atlântica. Entretanto, esses resultados não reduzem o valor das florestas maduras, principalmente em paisagens fragmentadas e para grupos mais sensíveis da fauna. Essas florestas devem ser protegidas, assim como deve ser garantida (e se preciso auxiliada) a regeneração das florestas secundárias, para que possam adquirir em longo prazo as condições necessárias à manutenção das espécies e dos grupos de espécies da fauna mais severamente afetados pela secundarização das florestas tropicais. / By sampling 28 sites in different regeneration stages in a continuous Atlantic forest area, in this master thesis we aimed to contribute to the understanding of the mechanisms associated with the wildlife changes observed during tropical forest regeneration, and thereby better understand the value of secondary forests for the conservation of tropical biodiversity. In the first part of the thesis we investigated the influence of regeneration on aspects of forest structure and food availability considered to be important to several wildlife groups. We found deeper leaf litter, and higher woody debris volume and fruit availability of an abundant understorey palm in the older-growth areas, while in areas in earlier stages we found higher vegetation connection, higher ground-dwelling arthropod biomass, total fruit availability, and availability of fruits of the most abundant understorey plant species. These modifications may be related to the wildlife changes observed during forest regeneration. Species that rely on features only found in older-growth forests, such as open space for movement, higher complexity of the forest floor, or certain food resources, could find limitations in younger forests, whereas species which do not depend on these resources could benefit from the higher total food availability, or higher 102 vegetation connection for movements, found in these areas. In the second part of the study, we assessed the effect of regeneration and of structural attributes and food availability on endemic (forest specialist) and non-endemic (habitat generalist) terrestrial small mammal species. As expected, we found that a group of species (habitat generalists) proliferate in younger areas, while the other group (forest specialists) is more common, although more subtly, in older-growth areas. These patterns were partly explained by the measured variables, especially food availability. Apparently, the generalist species are benefiting from the increased food availability found in younger forests, while specialist species have greater ability to occupy older-growth areas, where these resources are scarcer. Therefore, our data suggest a trade-off between competitive ability and ability to use abundant resources, as predicted by the successional niche mechanism, initially proposed to explain the succession of plant species. The characteristics observed in younger forests favored the proliferation of habitat generalist terrestrial small mammals. However, the positive effect of forest regeneration on specialist species, of more conservation concern, was less pronounced, so that the secondary forests harbored a rich terrestrial small mammal assemblage, and may therefore be an important tool to increase the area and connectivity in highly modified landscapes, such as those found in the Atlantic forest. However, these results do not diminish the value of old-growth forests, especially in fragmented landscapes and for more sensitive wildlife groups. These forests should be protected, as well as the regeneration of the secondary forests should be guaranteed (and assisted, if necessary), so that these areas could acquire in the long term the necessary conditions to maintain the species and the groups of species most adversely affected by the secondarization of the tropical forests.
343

Atributos individuais, formas de manejo e contexto ambiental: quais fatores determinam a chance de cachorros visitarem remanescentes florestais? / Individual traits, management and environmental context: which factors determine the chance of dogs visiting forest remnants?

Vinícius Leonardo Biffi 17 August 2017 (has links)
Invasões biológicas representam hoje a segunda maior ameaça à biodiversidade, e o homem desempenha papel fundamental na introdução de espécies exóticas potencialmente invasoras. O cachorro (Canis lupus familiaris) é uma dessas espécies. Presente em todos os continentes, é o carnívoro mais abundante do mundo, e pode causar impactos à fauna nativa através de efeitos letais e não letais da predação, competição, hibridização e transmissão de doenças, além de ser potencialmente importante na epidemiologia de zoonoses. Em áreas rurais, que concentram grande parte dos remanescentes de vegetação nativa no mundo, os cachorros são frequentemente criados soltos e circulam livremente, intensificando a chance de contato com a fauna nativa. Nesse trabalho, avaliamos a importância relativa de fatores associados a atributos individuais (sexo, idade, condição de saúde, comportamento exploratório, tamanho e raça), formas de manejo (incentivo do dono à movimentação, motivo para a criação, confinamento e frequência de alimentação) e contexto ambiental (proximidade à mata nativa) para determinar a chance de cachorros visitarem remanescentes florestais em paisagens fragmentadas de Mata Atlântica. Selecionamos oito paisagens de 2830 ha cada, nas quais visitamos todas as construções em áreas rurais a fim de entrevistar, através da aplicação de questionário, os responsáveis pela criação de cachorros e fotografar os cachorros. Utilizamos a imputação múltipla para estimar os dados faltantes (comuns em dados obtidos via questionários), gerando 10 conjuntos de dados imputados que foram analisados separadamente. Por meio de seleções de modelos através do Critério de Informação de Akaike, comparamos modelos candidatos com até cinco variáveis independentes para determinar a chance de cachorros visitarem remanescentes florestais. Nossos resultados nos permitem afirmar que quatro fatores - dois associados a atributos individuais e dois associados a formas de manejo - atuam em conjunto para determinar a chance de cachorros visitarem remanescentes florestais em paisagens rurais da Mata Atlântica. Cachorros maiores, mais exploradores, que recebem mais incentivo a se movimentar e que passam menos tempo confinados têm maior chance de visitar remanescentes florestais. A maior importância de atributos individuais e da forma de manejo está de acordo com a grande variação fenotípica existente entre cachorros e a variedade de modos como são manejados. Entre os atributos individuais, tanto características físicas como comportamentais são importantes, enquanto os aspectos chave da forma de manejo são aqueles mais diretamente relacionados à movimentação dos cachorros. Independentemente do tempo de confinamento, o incentivo do dono à movimentação do cachorro, em particular o estímulo para que o cachorro o acompanhe em visitas a remanescentes florestais, é fundamental. O contexto ambiental, em especial a proximidade do domicílio a áreas de mata nativa, por sua vez, é irrelevante dada a alta mobilidade dos cachorros. Nossos dados sugerem que a densidade de cachorros em paisagens rurais de Mata Atlântica é uma ordem de magnitude mais alta do que a de carnívoros de médio porte silvestres relativamente comuns, que muitos cachorros já tiveram contato direto com espécies silvestres, e que a vacinação e outras medidas profiláticas são relativamente incomuns. Todos esses dados indicam o potencial de efeitos negativos, tanto para a fauna silvestre como para o homem. Programas de redução destes impactos devem incluir tanto aspectos veterinários, como a expansão de campanhas públicas de profilaxia para além da vacinação antirrábica, quanto aspectos sociais, como a divulgação e conscientização dos potenciais problemas ocasionados pela entrada de cachorros em áreas de vegetação nativa, visando mudanças nas crenças, atitudes e comportamento da população humana / Biological invasions are today the second greatest threat to biodiversity, and humans play a significant role in the introduction of potentially invasive exotic species. The dog (Canis lupus familiaris) is one of such species. Distributed across all continents, the dog is the most abundant carnivore in the planet, and can impact wildlife through lethal and non-lethal effects of predation, competition, hybridization and disease transmission, besides being potentially important in the epidemiology of zoonoses. In rural areas where most remnants of native vegetation around the world are concentrated, most dogs are free-ranging, enhancing the chance of interactions with wildlife. Here, we evaluated the relative importance of factors associated with individual traits (sex, age, health condition, exploratory behaviour, size and breed), management (owner\'s incentive to movement, motive for raising, confinement and feeding frequency), and environmental context (proximity to native forest) to determine the chance of dogs visiting forest remnants in Atlantic Forest fragmented landscapes. We selected eight landscapes of 2830 ha each, where we visited all constructions in rural areas in order to interview dog owners by applying a questionnaire and to photograph dogs. We used multiple imputation to estimate missing data (common in data obtained through questionnaires), obtaining 10 imputed datasets that were analyzed separately. We compared candidate models with up to five independent variables to determine the chance of dogs visiting forest remnants through the Akaike Information Criterion. Our results indicate that four factors - two associated with individual traits and two associated with management - work together to determine the chance of dogs visiting forest remnants in Atlantic Forest rural landscapes. Larger dogs, and those that exhibit exploratory behaviour, are more stimulated to move or confined for shorter periods have greater chance of visiting forest remnants. The greater importance of factors associated with individual traits and management is in accordance with the ample phenotypic variation among dogs and the variety of ways they can be managed. Among individual traits, both morphological and behaviour characteristics are important, whereas the key aspects of management are those directly related to dog movement. Irrespective of the time confined, the owner\'s incentive to movement, in particular taking the dog to the forest, is a crucial aspect. In contrast, the environmental context, especially the proximity of the household to native forest, is irrelevant given the vagility of dogs. Our results suggest that the density of dogs across rural landscapes in the Atlantic forest is at least one order of magnitude higher than the density of relatively common medium-sized native carnivores, that several dogs have already had direct contact with wild species, and that vaccination and other prophylactic measures are relatively uncommon. All of these highlight the potential for negative effects on both wildlife and human population. Plans to reduce these effects should include not only veterinarian aspects, such as the expansion of public prophylactic campaigns beyond rabies vaccination, but also social aspects, such as the dissemination of information on the problems caused by dogs visiting native vegetation, aiming at changing people\'s beliefs, attitudes and behaviour
344

Reservas legais: critérios para localização e aspectos de gestão / Legal reserves: allocation criteria and management aspects

Victor Eduardo Lima Ranieri 30 June 2004 (has links)
A destruição de ambientes naturais é um dos mais reconhecidos problemas ambientais de âmbito global que, entre outras conseqüências, provoca impactos como perda de biodiversidade e degradação dos solos e da água. Tais impactos se refletem nos sistemas econômicos e sociais, o que tem conduzindo a discussão das estratégias de conservação da natureza por rumos que incluem, não somente questões técnicas, como também aspectos políticos. Além das estratégias de proteção baseadas em terras públicas, a conservação da biodiversidade e dos recursos hídricos em áreas sob domínio privado, é uma necessidade amplamente reconhecida. Seja em terras públicas ou particulares, a conservação de áreas naturais implica na imposição de limites às ações humanas, o que tende a gerar conflito de interesses. No Brasil, a chamada reserva legal - instrumento estabelecido pelo Código Florestal, Lei no. 7.441 de 1965, com a finalidade de garantir o uso sustentável dos recursos naturais, conservar biodiversidade e processos ecológicos limita o uso da propriedade rural e é foco de discussão entre proprietários, governos e setores da sociedade ligados à área ambiental. O presente trabalho analisa e propõe estratégias para a conservação da biodiversidade e dos recursos hídricos por meio do instrumento reserva legal, considerando critérios de alocação e aspectos de gestão, com ênfase na realidade dos biomas Mata Atlântica e cerrado. São analisados aspectos políticos, legais e institucionais relacionados à questão, identificados conflitos de interesses e sugeridos caminhos para o equacionamento desses conflitos. Sob o aspecto técnico, são propostos critérios e parâmetros para auxiliar o processo de tomada de decisão na escolha de áreas prioritárias para locação de reservas legais e apresentados cenários de ocupação do solo de uma região específica, considerando tais critérios. As informações levantadas permitem concluir que a estratégia brasileira baseada em instrumentos de comando e controle tem sido ineficaz no que tange à questão das reservas legais. Pontos de menor conflito entre os atores envolvidos, como a possibilidade de compensação de reservas legais fora dos limites das propriedades - utilizando instrumentos como o zoneamento ambiental e incentivos econômicos - podem tornar o instrumento reserva legal mais eficaz desde que: a) sejam definidos recortes territoriais adequados para a gestão compartilhada de florestas e água e b) sejam utilizados critérios técnicos claros para determinação de áreas prioritárias para locação de reservas legais, de modo a minimizar a subjetividade das normas gerais. Os resultados das simulações, materializados em oito cenários de ocupação, mostram que é possível, com a adoção de critérios técnicos objetivos, identificar locais mais propícios para implantação de reservas legais e, com isso, alterar parâmetros como tamanho, área central e conectividade entre fragmentos. Tais alterações podem tornar a paisagem mais favorável aos fluxos de fauna, à manutenção de espécies dependentes de grandes áreas de vida e de habitats sob menor efeito de borda, além de promover maior proteção dos solos e dos recursos hídricos. Questões como a responsabilidade por eventuais danos às reservas legais administradas em condomínios e aquelas relativas ao manejo de tais áreas para garantir sua conservação em longo prazo, entretanto, ainda exigem mais esforços para serem equacionadas. Esses esforços deverão se concentrar em estratégias inovadoras que, possivelmente, incluirão a participação da sociedade civil na gestão dessas áreas como, por exemplo, administradoras das reservas ou condomínios de reservas. / The destruction of natural environments is one of the most recognized worldwide environmental problems, which, among other consequences, causes impacts such as the loss of biodiversity and soil and water degradation. Such impacts reflect upon social and economic systems, which have lead the discussion on nature conservation strategies through paths which include not only technical but also political aspects. As well as protection strategies based on public land, biodiversity and water resource conservation in areas under private domain is a widely recognized need. On public or private land, the conservation of natural areas means imposing limits on human action, which tends to generate a conflict of interests. In Brazil, the so called legal reserve - a tool established by the Brazilian Forestry Code, Law 4,771 of 1965, with the aim of guaranteeing the sustainable use of natural resources, biodiversity conservation, and ecological processes - limits the use of rural properties and is the focus of discussions among landowners, governments, and entities linked to the environmental arena. This paper analyzes and proposes strategies for biodiversity, soil and water resource conservation through the legal reserve tool, considering designation criteria and management aspects, with a focus on the Atlantic Rainforest and cerrado. Political, legal, and institutional aspects related to the issue are analyzed, conflicts of interest are identified, and paths for the balance of these conflicts are suggested. Under a technical aspect, criteria and parameters to aid in the decision-making process for designating priority areas for legal reserves are proposed and scenarios for soil occupation of a specific region are presented, considering such criteria. The information gathered lead to the conclusion that the brazilian strategy is inefficacious. Points with less conflict among those involved, with the possibility of compensation for legal reserves outside property limits - based on tools like environmental zoning and economic incentives - could make the legal reserve instrument more efficient as long as: a) adequate territorial patches are defined for the co-management of forests and water and b) clear technical criteria are used to determine the priority areas designated as legal reserves, in a manner which minimizes the subjectivity of the general norms. The results of simulations, materialized in eight occupation scenarios, show that it is possible, with the adoption of objective technical criteria, to identify areas more susceptible to the implementation of legal reserves and thus change parameters such as size, central area, and connectivity between fragments. Such changes can make the landscape more favorable for fauna fluxes, for the maintenance of species dependent upon large area and habitats with less border effect, as well as promote greater protection of soils and water resources. Issues such as the responsibility for subsequent damage to legal reserves managed in shared natural areas and those related to the management of such areas to guarantee long-term conservation, however, still require more effort to be calculated. These efforts should concentrate on innovative strategies, which will include, for example, the participation of civil society in the management of reserves or shared natural areas.
345

Campesinato e biodiversidade no Cerrado : um estudo sobre o Assentamento Americana (Grão Mogol-MG) à luz da agroecologia / Peasantry and biodiversity at Cerrado biome : a study about the Americana settlement (Grão Mogol, Minas Gerais, Brazil) under the agroecology perspective

Carvalho, Igor Simoni Homem de, 1980- 10 January 2013 (has links)
Orientadores: Sonia Maria Pessoa Pereira Bergamasco, Mateus Batistella / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Filosofia e Ciências Humanas / Made available in DSpace on 2018-08-23T15:08:20Z (GMT). No. of bitstreams: 1 Carvalho_IgorSimoniHomemde_D.pdf: 11569012 bytes, checksum: 186f94f222917b3ed0d90cc7ab72076e (MD5) Previous issue date: 2013 / Resumo: O Assentamento Americana, localizado no município de Grão Mogol-MG e implantado em 2001, é uma proposta diferenciada de ocupação e uso dos recursos naturais do Cerrado, baseada na agroecologia, no extrativismo e no modo de vida dos habitantes tradicionais da região, denominados Geraizeiros. Esta tese tem como objetivo apresentar um estudo sobre este Assentamento Rural e as famílias assentadas, analisando de que forma sua implantação pode contribuir no debate sobre o campesinato e a biodiversidade no bioma Cerrado, mais especificamente nos cerrados do Norte de Minas. O marco teórico-metodológico principal utilizado é a agroecologia, recebendo aportes também de outras disciplinas como a sociologia rural e biologia da conservação. É apresentada a ideia de "referenciais camponeses" no intuito de analisar o perfil das famílias assentadas. A metodologia foi construída com base em entrevistas semi-estruturadas a 37 famílias assentadas e profissionais envolvidos com o Assentamento, além da análise de documentos e outros materiais pertinentes. Como resultado, chegou-se a elementos de grande relevância ao debate sobre campesinato e biodiversidade no Cerrado, que concernem especialmente às práticas agrícolas, pecuárias e extrativistas e ao grau de proximidade ou distanciamento dos referenciais camponeses presentes no Assentamento / Abstract: The Assentamento Americana (Americana settlement), located at Grão Mogol municipality (Minas Gerais state, Brazil), and created in 2001, is a differentiated proposal of land occupation and natural resources use on Cerrado biome (Brazilian savanna), based upon agroecology, extractivism (collection and use of native biodiversity products) and upon the way of life of traditional local inhabitants, called Geraizeiros. This thesis presents a study of this rural settlement and its families, analyzing how its implantation can contribute on the debate about peasantry and biodiversity at Cerrado biome, and specifically at the Norte de Minas region. The theoretic marks and methodology are based mainly on agroecology, with contributions also from rural sociology and biology conservation. It?s presented the idea of "peasant references" aiming to analyze the typology of the families. The methodology was constructed based on semi-structured interviews to 37 families of the Assentamento and other professionals linked to it, and also based on documents analyses. As a result, there were find elements of great to Cerrado peasantry and biodiversity debate, specially concerned to agriculture practices, cattle ranch and extractivism, and also to the proximity/distance from peasant references of the families studied / Doutorado / Aspectos Biológicos de Sustentabilidade e Conservação / Doutor em Ambiente e Sociedade
346

Mind the gap : People-centered biodiversity conservation in policy and practice in Cape Town, South Africa.

Israelsson, Elin January 2010 (has links)
Approaches to conserving biodiversity have traditionally left humans out of the picture. However, to separate between humans and protected areas has become increasingly criticized for being ethically problematic and ineffective. As a result, the political landscape for how biodiversity should be conserved has changed during the last 30 years. Instead of exclusive conservation practices, there is a request for so-called people-centered practices that tackle development and conservation jointly. However, several studies show a gap between public policies with people-centered ambitions and what is happening on areas assigned for biodiversity conservation. This study aims to understand if people-centered ideas are converted into conservation practices at four nature reserves in Cape Town, South Africa. The study also hopes to explain if the public-civil partnership Cape Flats Nature (CFN) is a useful arrangement in order to convert people-centered ambitions into practices. Using an ideal type analysis, conducting informant interviews and gathering documents, the findings suggest that people-centered practices are found at all four nature reserves. However, there are significant differences and the two nature reserves partnering with CFN have the most people-centered practices. In these cases, human well being is, for example, viewed to be an integral part of the objectives at nature reserves and fences that tend to keep people out are focused on to a lesser extent than in the other nature reserves that are not partnering with CFN. Even though there are no blueprint solutions, instruments such as CFN can be a useful arrangement for narrowing the gap between people-centered ambitions and conservation practices. However, further studies on for example social network analysis focusing on the role of bridging organizations would perhaps strengthen such claims.
347

Chocó challenges:communities negotiating matters of concern and care on Colombia’s margin

Acosta García, N. (Nicolás) 17 April 2018 (has links)
Abstract Chocó is a remote and biodiverse region located on Colombia’s Northern Pacific Coast. The region is home to indigenous Embera and Afro-descendant communities. Both communities share and contest a legacy of colonisation, violence, dispossession and discrimination. This thesis explores the ways in which the local communities of Chocó challenge and transform the matters that concern them. It focuses on their concerns over the effects of biodiversity conservation, development, and drug trade on their communities. It first investigates the challenges associated with doing research concerning both global and local concerns. Then, based on ethnographic fieldwork conducted in Chocó, it develops a methodology to address environmental value conflicts over the use of Utría National Park, located in the region. Third, the thesis studies the social protest of both local communities for the construction of a small hydroelectric power plant inside the park, finding that this protest for electricity reflects a complex post-colonial politics complementary to the discourse concerning political resistance as expressed by local and indigenous communities protesting against development. Fourth, drift-cocaine has been arriving recently to the coastal region of Chocó as a side effect of the country’s war on drugs. In Chocó, this phenomenon is referred to as the White Fish and is investigated here by situating its associated practices and transformations within the local context. Fifth, Utría National Park is explored visually as a place of rhythms and temporalities. Lastly, it argues that the mechanisms, grounded in concepts of solidarity and co-existence, which are employed by the local communities in negotiating the matters that concern them, provide alternative narratives to the ones often used to described them as in “poverty” and in need of “development”. / Tiivistelmä Chocó on syrjäinen ja biologisesti monimuotoinen alue Pohjois-Tyynenmeren rannikolla Kolumbiassa. Kyseinen alue on koti useille Embera-alkuperäiskansan jäsenille sekä Afrikasta polveutuville yhteisöille. Ryhmät jakavat ja haastavat kolonialismin, väkivaltaisuuksien, riiston sekä sorron värittämän historian. Tämä väitöskirja tarkastelee tapoja, joilla Chocón paikalliset yhteisöt haastavat ja muokkaavat heitä koskevia kysymyksenasetteluja. Se keskittyy yhteisöjä koskeviin huolenaiheisiin, jotka liittyvät biologisen monimuotoisuuden suojelun vaikutuksiin, kehitysinfrastruktuuriin ja huumekauppaan Ensimmäiseksi väitöskirja tarkastelee haasteita, jotka liittyvät maailmanlaajuisten muutosten ja paikallisten huolenaiheiden tutkimiseen. Tämän jälkeen työ kehittelee Chocóssa kerätyn etnografisen aineiston perusteella metodologiaa käsittelemään ympäristöön liittyviä arvoristiriitoja liittyen alueella sijaitsevan Utrían kansallispuiston käyttöön. Kolmanneksi väitöskirja tutkii paikallisyhteisöjen sosiaalista protestia liittyen pienen vesivoimalan rakentamiseen puiston alueelle. Havainnot haastavat tulkinnan, jonka mukaan infrastruktuurin hyväksyntä tai vastustaminen alkuperäiskansojen toimesta liittyy suoraan myös alkuperäiskansojen elämäntapojen puolustamiseen tai uhmaamiseen. Neljänneksi, ajelehtivaa kokaiinia on viime aikoina päätynyt Chocón rannikkoalueelle maan huumeiden vastaisen sodan seurauksena. Chocóssa ilmiöön viitataan nimellä Valkoinen kala, ja tässä työssä aihetta lähestytään tarkastelemalla siihen liittyviä käytänteitä ja muutoksia paikallisessa kontekstissa. Viidenneksi, Utrían kansallispuistoa tutkitaan visuaalisesti rytmien ja ajallisuuksien paikkana. Lopuksi esitetään, että paikallisten yhteisöjen hyödyntämät mekanismit heitä koskevissa keskusteluissa horjuttavat valtasuhteita epävarmoissa oloissa ja tarjoavat vaihtoehtoisia solidaarisuuden ja rinnakkaiselon narratiiveja, joilla lähestyä huolenaiheita.
348

Determining the diversity of nocturnal flying insects of the grassland in the Krugersdorp Nature Reserve

Pretorius, Estherna 02 May 2012 (has links)
M.Sc. / The grassland biome of South Africa harbours rich ecosystem diversity. Some of the distinctive features of grassland biodiversity in South Africa include globally significant centres of plant endemism, half of the country's endemic mammal species, a third of its endangered butterfly species and 10 of 14 of its globally threatened bird species. Grassland is one of the most inadequately maintained biomes in Southern Africa because 23% is under cultivation, 60% is irreversibly transformed and most of the remaining natural area is used as rangeland for livestock. Only 2% of the grassland biome is currently protected. Grasslands provide essential ecosystem services for economic development, but this biome also supports a large human population whose resource demands have serious environmental implications that threaten the grasslands‘ biodiversity. Urbanisation is possibly one of the major immediate threats to the grassland ecology in South Africa. This is also the case in the Cradle of Humankind World Heritage Site (COHWHS) and adjacent areas. New housing complexes and informal housing are encroaching on the COHWHS. Indigenous fauna and flora are being affected by ecologically insensitive urban development. This poses a major threat to the fauna of this region including the insects that occur in grassland habitats. The insects play a vital role as pollinators in grassland habitats and form an essential food source to a range of predators, including grass owls, shrews, bull frogs, lizards and bats. In order to conserve the insects and therefore the food web of which they form part, it is necessary to understand the diversity of the insects in the grassland in the dolomitic areas. The COHWHS is a world renowned heritage site devoted to the origin of humankind and is characterised by dolomitic caves. These caves are also the home of a large population of bats consisting of several species. The negative impact on the grasslands in the COHWHS and surroundings pose a threat to the survival of these bat populations if the food source they depend on is negatively affected. For this reason it is important to determine which flying nocturnal insect species are available in the grasslands surrounding bat roosts in the COHWHS and surroundings. 3 The choice of location for the primary trap site was made on the basis of its proximity to known bat roosts and the fact that it is situated in a nature reserve that, although the river is polluted, contains an otherwise relatively unspoilt grassland habitat. Sampling took place over a period of 14 months during which fluctuations in the insect population was observed. The fluctuations can be ascribed to seasonal climate changes and the three veld fires that occurred during this period. This fluctuation was most evident in the representatives of the Orders Lepidoptera and Coleoptera sampled.
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Guidelines for the formation of a community conservation and eco-tourist site on the KwaNibela Peninsula - KwaZulu-Natal

Van Meygaarden, Gerard Lambert 12 September 2012 (has links)
M.Sc. / KwaNibela Peninsula is situated directly adjacent to the World Heritage Site of Lake St. Lucia, and lies between the northern parts of False Bay and Lake St. Lucia. The community of KwaNibela is not unlike many other rural communities in Africa, found in pristine areas with very little development having taken place over the years. However the pristine environment of KwaNibela is under threat from the community themselves, through excessive hunting, slash and burn bush clearing, the encroachment of alien plant species, and various uncontrolled forms of harvesting from the bush. Around the world eco-tourism has been seen as a way to sustainably fund conservation and benefit the local communities. For the conservation of the sand forests and surrounding wetland areas of KwaNibela it is necessary for the local people to see the benefit of conserving the area in their everyday life. Ecotourism has been investigated as the solution to conservation problems at KwaNibela. However it should not be neglected that for hundreds of years the people of KwaNibela have been harvesting from the bush and it is a part of their everyday life, so sustainable ways of using the natural resources in the surrounding area are also being looked at. A plan to demarcate a conservancy area is put forward and to allow limited harvesting and promote and develop tourism in that area. The education of the local community is also of paramount importance to the progression of the project, right from primary school level to the adult community members. The tourism potential of the area is immense; but depends on the development of the right infrastructure and skills to make it a success.
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The ecology and conservation of Mackinder's eagle owls (Bubo capensis mackinderi) in central Kenya in relation to agricultural land-use and cultural attitudes

Ogada, Darcy L January 2008 (has links)
The loss of habitat to agriculture is a worldwide problem for biodiversity conservation. One species that has seemingly been able to adapt to the conversion of forests to farmlands is Mackinder’s eagle owl (Bubo capensis mackinderi), which inhabits highland areas, but little is known of its ecology, especially outside of protected areas. This study examined the impact of agricultural practices and farmer’s attitudes on the foraging and population ecology of the Mackinder’s eagle owl in central Kenya. Owl territories were monitored monthly from June 2004- October 2006 for signs of occupancy, breeding activity, mortality and to collect data on food resources. Nest site characteristics were measured for all known nests. Because previous studies showed an affinity for rodents, small mammals were trapped monthly using mark-recapture methodology. In each territory, the type and amount of farm crops were measured each month and farmers were interviewed about their knowledge and beliefs about owls. Mackinder’s eagle owls in central Kenya lived at extremely high density 0.87 owl pairs/km². This density was high compared to other populations of Mackinder’s eagle owl and to Eurasian eagle owl (Bubo bubo) populations in Europe. Breeding success was 48% over three years and this compared well with other species of eagle owl inhabiting human-disturbed areas. All nests and roosts were located in river valleys, and all successful nest sites were located on cliffs or other inaccessible rocky terrain. Nest sites were located adjacent to farms, which provided for both open hunting and an abundance of prey. Breeding activity was concentrated after the rainy seasons and this was likely linked to prey availability after the rains. Agricultural activities generally had a positive effect on rodent populations. Small mammal trapping results revealed that rodents were over 14 times more abundant in farms than in adjacent grassland habitat. This population of Mackinder’s eagle owl had a very catholic diet and consumed mostly mammalian prey species including hares, giant rats, root rats, grooved-tooth rats and small rodents. Small rodents accounted for almost half of the owls’ diet and when their numbers increased, owls responded by consuming more of them, indicating the importance of farming activities to this population of owls. Other populations of eagle owl inhabiting human-disturbed areas had diet widths positively related to levels of habitat disturbance. This result supported optimal foraging theory that more productive environments have predators with more specialized diets, while patchy environments have generalist predators. The ecology of this population of Mackinder’s eagle owls was heavily influenced by human agricultural activities, which generally had a positive effect on their population. Farming activities changed rapidly both within and between seasons as plots were small and neighbouring farmers planted various crops at different times of the year and this was enhanced by irrigation in some areas. Year-round availability of forage within farms had a positive effect on owl prey species, some of which increased relative to the type and amount of crops found in farms. However, 57% of owl injuries and mortalities that occurred were related either directly or indirectly to human activities. Cultural prejudices against owls remain the biggest threat to this population’s long-term persistence. Farmer education was shown to play a significant role in overcoming negative beliefs about owls. Because Mackinder’s eagle owls are highly adaptable to anthropomorphic landscape changes, largely due to their adaptability as food generalists, they are one of the few top predators remaining in this highly disturbed agricultural system. However, populations within agricultural areas remain especially vulnerable to negative human attitudes towards owls due to their close association with human activities.

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