A fragmentação e a perda de habitat são atualmente as principais ameaças à biodiversidade e funcionamento dos ecossistemas florestais. Em florestas tropicais fragmentadas e degradadas, tem sido observado um aumento na densidade, biomassa e na produtividade das comunidades de trepadeiras. Trepadeiras competem com árvores por recursos acima e abaixo do solo, e quando estão hiperabundantes podem alterar a estrutura e composição de espécies dos fragmentos florestais, bem como pode representar um filtro ecológico que mantém a regeneração natural estagnada por décadas. Especialmente nas bordas florestais, as trepadeiras têm se tornado hiperabundantes, mas as suas relações com as árvores e a regeneração natural nas bordas dos fragmentos florestais não são bem conhecidas. Diante disso, o objetivo desta tese foi verificar como trepadeiras em hiperabundância se relacionam com a comunidade arbustivo-arbórea e a regeneração natural em bordas de fragmentos florestais inseridos em paisagens agrícolas, analisar os possíveis desdobramentos dessas relações para a estrutura e composição de espécies nessas bordas e testar o manejo de trepadeiras como ferramenta de restauração da regeneração natural. Para a realização do presente estudo, foram selecionados três fragmentos de floresta estacional semidecídua, que apresentavam visivelmente trepadeiras em hiperabundância em suas bordas. A fim de analisar as relações entre trepadeiras, árvores e a regeneração natural, foram instaladas na borda de cada fragmento, oito parcelas permanentes de 150m2 (10mx15m), 24 parcelas ao todo, onde foram amostradas todas as árvores (DAP >= 5cm). Para o levantamento de trepadeiras, foi alocada uma subparcela de 50m2 (5mx10m) e a regeneração natural foi amostrada em três subparcelas de 4m2 (2mx2m). Foram calculadas variáveis descritoras dos três grupos amostrados, que foram correlacionadas entre si para investigar padrões nessas relações. Posteriormente, foi feita uma análise descritiva da estrutura e composição dessas bordas florestais com trepadeiras em hiperabundância. Para testar o efeito do manejo de trepadeiras em hiperabundância na regeneração natural, foi instalado um experimento de manejo, com corte total de todas as trepadeiras em metade das parcelas permanentes, a outra metade foi controle. As respostas do recrutamento, crescimento em altura, riqueza e composição da regeneração natural foi avaliada um ano após o manejo de trepadeiras. O presente trabalho traz em seu primeiro capítulo uma introdução sobre o papel ecológico das trepadeiras, suas relações com a estrutura de florestas e seu potencial para estagnar a sucessão florestal em fragmentos degradados, traz também o delineamento experimental geral. Nós investigamos no segundo capítulo, as relações entre trepadeiras em hiperabundância, árvores e a regeneração natural e fizemos uma análise descritiva da estrutura e composição de bordas florestais com trepadeiras em hiperabundância, inseridas em paisagem agrícola. No terceiro capítulo, nós demonstramos os efeitos iniciais do manejo de trepadeiras no recrutamento, crescimento em altura, riqueza e composição de espécies na regeneração natural. Trazemos também uma análise do rendimento operacional em função da densidade prévia de trepadeiras. Nós encontramos que a densidade de trepadeiras pequenas (<=2.5cm de diâmetro) e a proporção de árvores que apresentam ocupação severa da copa por trepadeiras (>=75%), têm relação negativa com a estrutura da comunidade arbórea e com a regeneração natural. Já a densidade de trepadeiras grandes (>2.5cm) tem relação positiva com características de floresta madura (maior biomassa e projeção da copa no solo, por exemplo). A estrutura predominante nas bordas estudadas inclui densidades altíssimas de trepadeiras (parcelas com até 78 trepadeiras/árvore) e mais de 80% dos indivíduos com as copas ocupadas por trepadeiras onde, em média, metade dessas árvores apresentam ocupação severa e a regeneração natural está comprometida. Nossos resultados ressaltam evidências que trepadeiras em hiperabundância podem contribuir com a degradação da estrutura da comunidade arbórea e com a supressão da regeneração natural nas bordas florestais. O manejo de trepadeiras proporcionou aumento no recrutamento e na diversidade da regeneração natural já no primeiro de avaliação. Também houve uma tendência de efeito positivo no crescimento em altura de espécies não pioneiras. Essa ação de manejo de trepadeiras em fragmentos florestais degradados é mais rentável comparada a técnicas convencionais de restauração ecológica (plantio de mudas para o reflorestamento de áreas que foram totalmente desmatadas, por exemplo), que são amplamente adotadas no país, indicando ser uma opção economicamente viável. Ao testar o manejo de trepadeiras, reconhecemos que essa prática é útil para a restauração da regeneração natural em bordas florestais com trepadeiras em hiperabundância e, consequentemente, para a retomada da sucessão florestal em fragmentos florestais degradados inseridos em paisagens agrícolas. / Fragmentation and loss of habitat are currently the main threats to the biodiversity and functioning of forest ecosystems. In fragmented and degraded tropical forests, there has been an increase in density, biomass and productivity of climbing communities. Climbers compete with trees for above and below ground resources, and when they are overabundant, they can alter the structure and composition of forest fragments, as well as represent an ecological filter that keeps natural regeneration arrested for decades. Especially on forest edges, climbing plants have become overabundant, but their relationships with trees and natural regeneration at the edges of forest fragments are not well known. Therefore, the objective of this thesis was to verify how overabundant climbers relate to the shrub-tree community and natural regeneration on forest edges of fragments inserted in agricultural landscapes, to analyze the possible unfolding of these relationships for the structure and species composition on edges and to test the management of climbing plants as a tool to restore natural regeneration. For the accomplishment of the present study, three fragments of semideciduous seasonal forest were selected, that one visibly presented overabundant climbers in in its edges. In order to analyze the relationships between climber plants, trees and natural regeneration, eight permanent plots of 150m2 (10mx15m), 24 plots in total, were sampled on the edge of each fragment, where all trees (DAP >= 5cm) were sampled. A subplot of 50m2 (5mx10m) was allocated for climber plants samples, and natural regeneration was sampled in three subplots of 4m2 (2mx2m). Descriptive variables were calculated from the three sampled groups, which were correlated with each other to investigate patterns in these relationships. Subsequently, a descriptive analysis was made of the structure and composition of these forest edges with hyperabundant climbers. To test the effect of the management of overabundant climbers on natural regeneration, a management experiment was installed, with a total cut of all climbers in half of the permanent plots, four plots, the other half was control. The responses of recruitment, growth in height, richness and composition of natural regeneration was evaluated one year after the management. This work presents in its first chapter an introduction on the ecological role of climbers, their relationships with the forest structure and their potential to stagnate the forest succession in degraded fragments, also brings the general experimental design. We investigated in the second chapter, the relationships between hyperabundant climbers, trees and natural regeneration, and we did a descriptive analysis of the structure and composition of forest edges inserted in agricultural landscape with overabundant climbers. In the third chapter, we demonstrate the initial effects of management of climbers on recruitment, growth in height, richness, and species composition in natural regeneration. We also present an analysis of the operational performance in function of the previous density of climbers. We found that the density of small climber plants (<=2.5cm in diameter) and the proportion of trees with severe crown occupancy by climbers (>=75%) are negatively related to tree structure and natural regeneration. However, the density of large climbers (> 2.5 cm) has a positive relation with mature forest characteristics (greater biomass and crown projection in the soil, for example). The predominant structure in the studied forest edges includes very high densities of climbers (plots with up to 78 climbers / tree) and more than 80% of individuals with crown occupied by climbers where, on average, half of these trees are severely occupied and natural regeneration is compromised. Our results highlight evidence that hyperabundant climbers can contribute to the degradation of the tree community structure and the suppression of natural regeneration at the forest edges. The management of climbers provided an increase in recruitment and in the diversity of natural regeneration in the first-year evaluation. There was also a trend of positive effect on growth in height of non-pioneer species. This action of management of climbers in degraded forest fragments is more profitable compared to the conventional techniques of ecological restoration (planting seedlings for the reforestation of areas that have been totally deforested, for example), that are widely adopted in the country, indicating that it is economically viable. In testing the management of climbers, we recognize that this practice is useful for the restoration of natural regeneration on forest edges with overabundant climbers and, consequently, for the resumption of forest succession in degraded forest fragments inserted in agricultural landscapes.

In South Australia, overabundant kangaroo populations are managed through commercial harvest. Kangaroo harvest rates over the past decade have averaged only 40% of the harvest quota despite strong demand for the product. With kangaroo populations increasing, the problem of low kangaroo harvest rate in South Australia requires research attention. Previous research regarding kangaroo harvest has focused on questions of biology and ecology and little attention has been directed towards advancing understanding of the human dimensions of kangaroo management. This research sought to fill this gap in knowledge. Qualitative research methods were most appropriate due to the focus on social and institutional dimensions of kangaroo management. Data were collected during interviews with people involved in commercial kangaroo harvest: landholders, harvesters and meat processors. The main topics covered were regnlations and policy, economic issues, the rights and interests of various industry stakeholders and South Australian harvest rates. The views of Aboriginal people were also sought including the significance of kangaroos to Aboriginal people, access to kangaroos for subsistence harvest, kangaroo management and the kangaroo industry. The main findings of this research are presented as a series of peer-reviewed articles: • Article I introduces the research topic and presents preliminary findings of this study. • Article 2 establishes that an increase in South Australia's low harvest rate is needed if kangaroo harvest is to make greater contributions to regional communities, and recommends institutional reform to meet this goal. • Article 3 examines the management regime for kangaroos in South Australia and shows how the informal rules in use are often incongruent with the formal rules established by management administrators. • Article 4 describes the undervalued position of landholders in the kangaroo industry and the obstacles to landholders deriving income from kangaroo harvest. • Article 5 discusses the cultural basis of Aboriginal perspectives on kangaroo harvest and includes suggestions for appropriate ways for Aboriginal people to contribute to kangaroo management. The main findings of this research were applied in a comparative study of kangaroo management with that of moose management in Finland. This study found that similar social and institutional factors impact on the management of moose and kangaroos. The broad lessons for wildlife management drawn from the comparative study are: • mobile wildlife resources require flexible management systems • stakeholder involvement is critical to management • hunters/harvesters are conservative of their resource base • declining harvester numbers need to be addressed through support, incentives and training. These lessons can be applied in part, or in whole, to other overabundant and mobile wildlife species. Thus this thesis makes contribution to kangaroo management by making specific recommendations for the industry, but also contributes to wildlife management in a broader sense through the application of findings to other species. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1298303 / Thesis (Ph.D.) -- University of Adelaide, School of Agriculture, Food and Wine, 2007

In South Australia, overabundant kangaroo populations are managed through commercial harvest. Kangaroo harvest rates over the past decade have averaged only 40% of the harvest quota despite strong demand for the product. With kangaroo populations increasing, the problem of low kangaroo harvest rate in South Australia requires research attention. Previous research regarding kangaroo harvest has focused on questions of biology and ecology and little attention has been directed towards advancing understanding of the human dimensions of kangaroo management. This research sought to fill this gap in knowledge. Qualitative research methods were most appropriate due to the focus on social and institutional dimensions of kangaroo management. Data were collected during interviews with people involved in commercial kangaroo harvest: landholders, harvesters and meat processors. The main topics covered were regnlations and policy, economic issues, the rights and interests of various industry stakeholders and South Australian harvest rates. The views of Aboriginal people were also sought including the significance of kangaroos to Aboriginal people, access to kangaroos for subsistence harvest, kangaroo management and the kangaroo industry. The main findings of this research are presented as a series of peer-reviewed articles: • Article I introduces the research topic and presents preliminary findings of this study. • Article 2 establishes that an increase in South Australia's low harvest rate is needed if kangaroo harvest is to make greater contributions to regional communities, and recommends institutional reform to meet this goal. • Article 3 examines the management regime for kangaroos in South Australia and shows how the informal rules in use are often incongruent with the formal rules established by management administrators. • Article 4 describes the undervalued position of landholders in the kangaroo industry and the obstacles to landholders deriving income from kangaroo harvest. • Article 5 discusses the cultural basis of Aboriginal perspectives on kangaroo harvest and includes suggestions for appropriate ways for Aboriginal people to contribute to kangaroo management. The main findings of this research were applied in a comparative study of kangaroo management with that of moose management in Finland. This study found that similar social and institutional factors impact on the management of moose and kangaroos. The broad lessons for wildlife management drawn from the comparative study are: • mobile wildlife resources require flexible management systems • stakeholder involvement is critical to management • hunters/harvesters are conservative of their resource base • declining harvester numbers need to be addressed through support, incentives and training. These lessons can be applied in part, or in whole, to other overabundant and mobile wildlife species. Thus this thesis makes contribution to kangaroo management by making specific recommendations for the industry, but also contributes to wildlife management in a broader sense through the application of findings to other species. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1298303 / Thesis (Ph.D.) -- University of Adelaide, School of Agriculture, Food and Wine, 2007