Compared to natural forests, fast-growing plantations of exotic species such as Pinus radiata are often perceived as marginal habitat or unsuitable habitat for most native species. By studying Coleoptera (beetles) in a variety of landscape elements (pasture, native forest and different aged Pinus radiata stands) in a highly modified and fragmented landscape in New Zealand I aimed to determine the value of exotic plantation forests for native biodiversity, and how these species are affected by different sized clearfell harvest areas. Pitfall trap sampling of beetles showed that plantation forest stands can provide suitable complimentary habitat to native forest for many species. Rarefied species richness of Carabidae, Scarabaeidae and Scolytinae was not significantly different between habitats, however, habitat types differed significantly in their beetle community composition. Comparing different production habitats, Pinus radiata stands had a beetle community composition most similar to native forest. However, a small minority of species, e.g., Dichrochile maura, were restricted to native forest habitat highlighting the importance of retaining indigenous ecosystems within plantations. Unlike human modified habitats, native forests did not provide suitable habitat for exotic species. Clearfell harvesting is controversial and its impact on biodiversity is a key constraint for many forest certification programs, such as that administered by the Forest Stewardship Council (FSC). Despite this, no replicated manipulative experimental studies of the impact of different sized clearfell harvest areas on biodiversity have been undertaken at scales relevant to the New Zealand forest industry. One potential model of the impact of different clearfell harvest sizes is the concept of a threshold size. A threshold scenario may occur where clearfell harvest impacts increase at a rate disproportionate to the change in clearfell size over a small range of harvest areas, but impacts remain relatively unchanged either side of the threshold zone. I sampled Coleoptera in experimentally created 0.01, 0.05, 0.5, 5.0, 50 and 500 ha clearfells within Pinus radiata plantations in the central North Island of New Zealand. The wide range of clearfell harvest sizes, including some very small areas, such as 0.01 ha was instigated in an attempt to document potential clearfell harvest size thresholds. Rarefied native beetle species richness was higher in harvest areas compared to adjacent mature plantation stands. The beetle species richness in 5 ha and 500 ha harvest areas was significantly greater species than that in small 0.01 - 0.5 ha harvest areas. Although, the high beetle diversity recorded in 500 ha clearfells should be treated with caution due to confounding spatial autocorrelation. The degree of change in beetle community composition increased with increasing clearfell harvest area. Beetle assemblages in large harvest areas were less similar to their paired adjacent mature forest than smaller harvest areas. Although, constrained multivariate ordination techniques did show a short-term change in beetle species composition between recently clearfelled harvest areas of as little as 0.05 ha and adjacent mature P. radiata stands. The colonisation by open-habitat disturbance-adapted species was a key driver of this change, some species dispersed into clearfelled stands in significant densities within days post-harvest. Overall, there were no distinct short-term trends to the change in species richness as a function of increasing harvest area that would suggest an ecological impact threshold response. If short-term outcomes of clearfell harvesting are ameliorated by successful recolonisation, the long-term spatial arrangement of different aged stands becomes more important for the maintenance of biodiversity at the landscape level than short-term consequences of harvesting. By sampling selected beetle taxa in 1, 2, 4, 8, 16 and 26 year-old stands, I found that the abundance of seven out of eight of the species selected for analysis recovered to levels similar to those in adjacent mature forest within the timeframe of a single harvest rotation. Individual species utilised different aged stands, indicating different life-history strategies. For example, open-habitat, disturbance-adapted species such as Cicindela tuberculata and Sitona discoideus were prominent in young stands, and forest species such as Pycnomerus sophorae and Paracatops phyllobius were highly abundant in older stands. These alternative life-history strategies highlight the benefits of maintaining a mixture of different aged stands to increase biodiversity at the landscape level. This thesis fills an important gap in our knowledge of biodiversity in production landscapes. I show that plantation forests have value as complimentary habitat to native forest and they make an important contribution to the maintenance of biodiversity at the landscape level. Although clearfell harvesting is a severe disturbance to the forest ecosystem, the long-term recovery of beetle populations suggests that harvesting is not the key limiting factor to the enhancement of biodiversity in the plantation forests studied. This unusual situation is possibly the result of prior land-use history, as many plantations were established on degraded pastoral land, and harvest-sensitive species are unlikely to have survived this initial land-use change. As such, the severity of the long-term impacts of clearfell harvesting on biodiversity are likely to be context specific and will vary accordingly. The importance of spatial heterogeneity of habitat elements, including different aged plantation stands and native forest remnants, needs to be investigated in more detail to determine what limits biodiversity in this plantation landscape. Key points to consider are the proximity to, and proportion of, native forest cover in the landscape and the degree of connectivity among native remnants. It is these landscape-level attributes that may determine biodiversity at a regional scale, and more emphasis should be placed on landscape scale factors and there interaction with stand specific forest management practices. For example, the spatial mosaic of harvesting areas may need to be of a finer-scale when there are fewer native remnants within the landscape.

The environmental problems facing the world today are largely attributable to anthropogenic activities and landscape change. Addressing these challenges in an evidence-based way requires an understanding of precisely how species and ecosystems are responding to human impacts. Discerning linkages between stressors and their ecological repercussions, and using this to inform conservation, can be challenging due to the complexity and uncertainty of ecological research. I focused on the responses of five wide-ranging large mammal species – gray wolf (Canis lupus), Canada lynx (Lynx canadensis), coyote (Canis latrans), white-tailed deer (Odocoileus virginianus) and moose (Alces alces) – to human footprint (measure of human infrastructure and landscape change), using 12 years (2001-2013) of snowtrack surveys conducted across the boreal forest of Alberta. I explored three key challenges to discerning the linkages between ecological dynamics and management actions. First, I asked whether the direction and magnitude of species responses vary depending on the spatial extent and grain of the study. Second, I asked whether these species respond more strongly to individual footprint features or to the cumulative effects of footprint (measured as total footprint), and whether responses to footprint are consistent across species. Third, I evaluated the utility of thresholds for large mammal management and asked whether there is evidence for consistent threshold responses to total footprint across scales. In addressing the first two questions, I evaluated a set of generalized linear mixed effects models (GLMM) relating the relative abundance of each species to individual and cumulative effects of human footprint, using an information-theoretic approach. I compared the direction of species responses across our regional study area (approximately 400,000 km2) to those reported in previous smaller-extent studies (median 1,525 km2), and compared responses across three spatial grains (250m, 1500m, and 5000m transect buffers). In addressing the third question, I conducted a review on the utility of ecological thresholds, described as abrupt changes in the response to a continuous driver, for large mammal management. I further tested for thresholds in species responses to total footprint by comparing linear models (logistic regression) to piecewise regression models. I compared threshold values between two grains (approximately 33km2 - 1500m transect buffer, and 5500km2 - grouping transects into clusters), and across four regions (boreal forest extent, three landscape planning units). I found that the direction of species responses varied with spatial extent, but not grain, and that species responded strongly to a broad suite of footprint features, indicating the need to manage for cumulative effects. Despite the appeal of ecological thresholds, using these as targets is challenging and the success of doing so has rarely been evaluated. I found threshold models to be better supported than linear ones across species, but due to variability and uncertainty in threshold values, the results are more suited as guidelines or hypotheses to be further tested, as opposed to specific management targets. Translating research on complex ecological systems into management actions is a continuing challenge, yet, ongoing biodiversity monitoring and adaptive management may refine our existing tools, and ultimately lead to better environmental stewardship. / Graduate / 2017-09-05 / 0329

Compared to natural forests, fast-growing plantations of exotic species such as Pinus radiata are often perceived as marginal habitat or unsuitable habitat for most native species. By studying Coleoptera (beetles) in a variety of landscape elements (pasture, native forest and different aged Pinus radiata stands) in a highly modified and fragmented landscape in New Zealand I aimed to determine the value of exotic plantation forests for native biodiversity, and how these species are affected by different sized clearfell harvest areas. Pitfall trap sampling of beetles showed that plantation forest stands can provide suitable complimentary habitat to native forest for many species. Rarefied species richness of Carabidae, Scarabaeidae and Scolytinae was not significantly different between habitats, however, habitat types differed significantly in their beetle community composition. Comparing different production habitats, Pinus radiata stands had a beetle community composition most similar to native forest. However, a small minority of species, e.g., Dichrochile maura, were restricted to native forest habitat highlighting the importance of retaining indigenous ecosystems within plantations. Unlike human modified habitats, native forests did not provide suitable habitat for exotic species. Clearfell harvesting is controversial and its impact on biodiversity is a key constraint for many forest certification programs, such as that administered by the Forest Stewardship Council (FSC). Despite this, no replicated manipulative experimental studies of the impact of different sized clearfell harvest areas on biodiversity have been undertaken at scales relevant to the New Zealand forest industry. One potential model of the impact of different clearfell harvest sizes is the concept of a threshold size. A threshold scenario may occur where clearfell harvest impacts increase at a rate disproportionate to the change in clearfell size over a small range of harvest areas, but impacts remain relatively unchanged either side of the threshold zone. I sampled Coleoptera in experimentally created 0.01, 0.05, 0.5, 5.0, 50 and 500 ha clearfells within Pinus radiata plantations in the central North Island of New Zealand. The wide range of clearfell harvest sizes, including some very small areas, such as 0.01 ha was instigated in an attempt to document potential clearfell harvest size thresholds. Rarefied native beetle species richness was higher in harvest areas compared to adjacent mature plantation stands. The beetle species richness in 5 ha and 500 ha harvest areas was significantly greater species than that in small 0.01 - 0.5 ha harvest areas. Although, the high beetle diversity recorded in 500 ha clearfells should be treated with caution due to confounding spatial autocorrelation. The degree of change in beetle community composition increased with increasing clearfell harvest area. Beetle assemblages in large harvest areas were less similar to their paired adjacent mature forest than smaller harvest areas. Although, constrained multivariate ordination techniques did show a short-term change in beetle species composition between recently clearfelled harvest areas of as little as 0.05 ha and adjacent mature P. radiata stands. The colonisation by open-habitat disturbance-adapted species was a key driver of this change, some species dispersed into clearfelled stands in significant densities within days post-harvest. Overall, there were no distinct short-term trends to the change in species richness as a function of increasing harvest area that would suggest an ecological impact threshold response. If short-term outcomes of clearfell harvesting are ameliorated by successful recolonisation, the long-term spatial arrangement of different aged stands becomes more important for the maintenance of biodiversity at the landscape level than short-term consequences of harvesting. By sampling selected beetle taxa in 1, 2, 4, 8, 16 and 26 year-old stands, I found that the abundance of seven out of eight of the species selected for analysis recovered to levels similar to those in adjacent mature forest within the timeframe of a single harvest rotation. Individual species utilised different aged stands, indicating different life-history strategies. For example, open-habitat, disturbance-adapted species such as Cicindela tuberculata and Sitona discoideus were prominent in young stands, and forest species such as Pycnomerus sophorae and Paracatops phyllobius were highly abundant in older stands. These alternative life-history strategies highlight the benefits of maintaining a mixture of different aged stands to increase biodiversity at the landscape level. This thesis fills an important gap in our knowledge of biodiversity in production landscapes. I show that plantation forests have value as complimentary habitat to native forest and they make an important contribution to the maintenance of biodiversity at the landscape level. Although clearfell harvesting is a severe disturbance to the forest ecosystem, the long-term recovery of beetle populations suggests that harvesting is not the key limiting factor to the enhancement of biodiversity in the plantation forests studied. This unusual situation is possibly the result of prior land-use history, as many plantations were established on degraded pastoral land, and harvest-sensitive species are unlikely to have survived this initial land-use change. As such, the severity of the long-term impacts of clearfell harvesting on biodiversity are likely to be context specific and will vary accordingly. The importance of spatial heterogeneity of habitat elements, including different aged plantation stands and native forest remnants, needs to be investigated in more detail to determine what limits biodiversity in this plantation landscape. Key points to consider are the proximity to, and proportion of, native forest cover in the landscape and the degree of connectivity among native remnants. It is these landscape-level attributes that may determine biodiversity at a regional scale, and more emphasis should be placed on landscape scale factors and there interaction with stand specific forest management practices. For example, the spatial mosaic of harvesting areas may need to be of a finer-scale when there are fewer native remnants within the landscape.

Por meio de uma amostragem padrozinada de longa duração, realizamos levantamentos de pequenos mamíferos com armadilhas de interceptação e queda em 68 sítios distribuídos em seis paisagens de 10.000 ha (três em mata contínua e três em paisagens fragmentadas) localizadas em três regiões do Planalto Atlântico Paulista. As paisagens fragmentadas compreendem diferentes quantidades de matas remanescentes, 50%, 30% e 10%, porcentagens acima e próximas dos limites superior e inferior do limiar teórico de fragmentação (10-30%). A presente tese de doutoramento foi dividida em quatro capítulos e duas abordagens principais. A primeira delas (Capítulo 2) teve por objetivo avaliar se os pequenos mamíferos listados como ameaçados de extinção são afetados pela fragmentação e pela qualidade dos remanescentes de Mata Atlântica do Planalto Atlântico Paulista. Para isso, utilizamos os dados coletados nos 68 sítios amostrados, os quais estavam distribuídos em oito categorias: nove em matas maduras contínuas, nove em matas secundárias contínuas, quatro em fragmentos grandes e 11 em fragmentos pequenos da paisagem com 50% de remanescentes, sete em fragmentos grandes e 13 em fragmentos pequenos da paisagem com 30% de remanescentes, e quatro em fragmentos grandes e 11 em fragmentos pequenos da paisagem com 10% de remanescentes. Avaliamos se 10 espécies de pequenos mamíferos listados como ameaçados de extinção e cinco espécies endêmicas comuns nas mata contínuas e ausentes das listas vermelhas são afetados igualmente pela fragmentação, na escala da paisagem e da mancha, e pela qualidade dos remanescentes de Mata Atlântica. Nenhuma das espécies analisadas, independentemente do grau de ameaça ou de raridade, respondeu a variação do estádio de regeneração das matas contínuas. Por outro lado, nossos dados mostraram que as espécies endêmicas comuns respondem de forma mais congruente e negativamente à perda e fragmentação da Mata Atlântica do que as ameaçadas, as quais tanto podem não ser afetadas quanto ser positivamente ou negativamente afetadas pela fragmentação. Assim, sugerimos a separação das espécies em dois grupos nas listas vermelhas (naturalmente raras versus afetadas pelas ações antrópicas) e a utilização de outros critérios para avaliar o status de ameaça das espécies mais comuns, como a resposta à perda e fragmentação do habitat e a especificidade ao habitat na forma de endemismos e de grau de tolerância a matriz. A segunda abordagem (Capítulo 3) teve como objetivo verificar a influência do contexto (paisagem) e do tamanho do fragmento em paisagens com quantidades diferentes de remanescentes sobre a riqueza e abundância de espécies endêmicas e não-endêmicas. Para isso, utilizamos dados de 50 dos 68 fragmentos amostrados, localizados nas três paisagens 114 fragmentadas com 50%, 30% e 10% de remanescentes. A partir da avaliação da plausibilidade de oito modelos de regressão, que expressam visões teóricas alternativas da importância do contexto e da área dos fragmentos, investigamos se a influência positiva da área das manchas de floresta é mais forte (1) para as espécies endêmicas e (2) na paisagem próxima ao limite superior do limiar de fragmentação (sensu Andrén, 1994), já que em contexto de muita mata remanescente, fragmentos pequenos e grandes poderiam abrigar populações viáveis, e em contexto de pouca mata remanescente, espécies sensíveis já teriam desaparecido. Com exceção da riqueza de espécies não-endêmicas, modelos que incluem o contexto foram as hipóteses mais plausíveis para descrever a variação da riqueza e abundância das espécies de pequenos mamíferos. Como esperado, a influência positiva da área do fragmento foi mais importante na paisagem com 30% de floresta para a maioria das espécies de pequenos mamíferos endêmicos, enquanto que os modelos que incluem a influência da área do fragmento não estiveram entre os mais plausíveis para as espécies não-endêmicas. Nossos resultados corroboram a existência de um limiar de fragmentação e indicam que, ainda que os limiares variem entre espécies, é possível identificar grupos com respostas semelhantes à perda e fragmentação do habitat, auxiliando as políticas de manejo e conservação. / A long-term standardized survey of the Atlantic Forest small mammals was conducted using pitfall traps in 68 sites distributed in six 10.000-ha landscapes (three in continuous forest and three in fragmented landscapes) located in three regions in the Atlantic Plateau of São Paulo. The fragmented landscapes harbored different amounts of remnants, 50%, 30% and 10%, percentages above or within the superior and inferior limits of the theoretical fragmentation threshold (10-30%). This thesis was divided in four chapters e two main approaches. The first approach (Chapter 2) aimed to evaluate if small mammals listed as threatened were affected by forest fragmentation and quality in the Atlantic Plateau of São Paulo state. For this, we used data from 68 sites distributed in eight categories: nine in mature continuous forests, nine in secondary continuous forests, four in large and 11 in small patches in the landscape with 50% of remnants, seven in large and 13 in small patches in the landscape with 30% of remnants and four in large and 11 in small patches in the landscape with 10% of remnants. We investigated if 10 threatened small mammals and five non-threatened endemic species commonly found in continuous forests were equally affected by fragmentation, at the landscape and patch scales, and by forest quality. Regardless of threat or rarity level, no analyzed species responded to differences in the regeneration stage in continuous forests. On the other hand, our data showed that common endemic species respond more strongly and negatively to the loss and fragmentation of the Atlantic Forest than threatened species, which either may not be affected by fragmentation, or be positively or negatively affected. we suggest separating species in two groups (naturally rare versus affected by human impact) in the Red Lists and including different criteria to evaluate common species such as response to habitat loss and fragmentation as well as habitat specificity in terms of endemism and level of matrix tolerance. The second approach (Chapter 3) aimed to evaluate the effects of context (landscape) and patch area in landscapes with different amounts of remnants on the richness and abundance of the endemic and non-endemic species. We used data from 50 sites located in the three fragmented landscapes. By analyzing the plausibility of eight regression models, which express alternative theoretical hypothesis about the importance of context and patch area, we investigate if the positive influence of patch area was stronger (1) for endemic species and (2) in the landscape within the superior limit of the fragmentation threshold (sensu Andrén, 1994), since in a context of high proportion of remnants, small and large patches could harbor viable populations and in a context of low proportion of remnants, sensitive species would have gone extinct. Except for the non116 endemic species richness, the models including context were the most plausible hypothesis to describe small mammal richness and abundance variations. As expected, the positive influence of patch area was more important in the landscape with 30% of remnants for the majority of the endemic small mammals, whereas the models including patch area were not among the most plausible ones for the non-endemic species. Our data corroborate the existence of a fragmentation threshold and point out that, although thresholds vary among species, it is possible to identify groups with similar response to habitat loss and fragmentation, directing management and conservation policies.

Por meio de uma amostragem padrozinada de longa duração, realizamos levantamentos de pequenos mamíferos com armadilhas de interceptação e queda em 68 sítios distribuídos em seis paisagens de 10.000 ha (três em mata contínua e três em paisagens fragmentadas) localizadas em três regiões do Planalto Atlântico Paulista. As paisagens fragmentadas compreendem diferentes quantidades de matas remanescentes, 50%, 30% e 10%, porcentagens acima e próximas dos limites superior e inferior do limiar teórico de fragmentação (10-30%). A presente tese de doutoramento foi dividida em quatro capítulos e duas abordagens principais. A primeira delas (Capítulo 2) teve por objetivo avaliar se os pequenos mamíferos listados como ameaçados de extinção são afetados pela fragmentação e pela qualidade dos remanescentes de Mata Atlântica do Planalto Atlântico Paulista. Para isso, utilizamos os dados coletados nos 68 sítios amostrados, os quais estavam distribuídos em oito categorias: nove em matas maduras contínuas, nove em matas secundárias contínuas, quatro em fragmentos grandes e 11 em fragmentos pequenos da paisagem com 50% de remanescentes, sete em fragmentos grandes e 13 em fragmentos pequenos da paisagem com 30% de remanescentes, e quatro em fragmentos grandes e 11 em fragmentos pequenos da paisagem com 10% de remanescentes. Avaliamos se 10 espécies de pequenos mamíferos listados como ameaçados de extinção e cinco espécies endêmicas comuns nas mata contínuas e ausentes das listas vermelhas são afetados igualmente pela fragmentação, na escala da paisagem e da mancha, e pela qualidade dos remanescentes de Mata Atlântica. Nenhuma das espécies analisadas, independentemente do grau de ameaça ou de raridade, respondeu a variação do estádio de regeneração das matas contínuas. Por outro lado, nossos dados mostraram que as espécies endêmicas comuns respondem de forma mais congruente e negativamente à perda e fragmentação da Mata Atlântica do que as ameaçadas, as quais tanto podem não ser afetadas quanto ser positivamente ou negativamente afetadas pela fragmentação. Assim, sugerimos a separação das espécies em dois grupos nas listas vermelhas (naturalmente raras versus afetadas pelas ações antrópicas) e a utilização de outros critérios para avaliar o status de ameaça das espécies mais comuns, como a resposta à perda e fragmentação do habitat e a especificidade ao habitat na forma de endemismos e de grau de tolerância a matriz. A segunda abordagem (Capítulo 3) teve como objetivo verificar a influência do contexto (paisagem) e do tamanho do fragmento em paisagens com quantidades diferentes de remanescentes sobre a riqueza e abundância de espécies endêmicas e não-endêmicas. Para isso, utilizamos dados de 50 dos 68 fragmentos amostrados, localizados nas três paisagens 114 fragmentadas com 50%, 30% e 10% de remanescentes. A partir da avaliação da plausibilidade de oito modelos de regressão, que expressam visões teóricas alternativas da importância do contexto e da área dos fragmentos, investigamos se a influência positiva da área das manchas de floresta é mais forte (1) para as espécies endêmicas e (2) na paisagem próxima ao limite superior do limiar de fragmentação (sensu Andrén, 1994), já que em contexto de muita mata remanescente, fragmentos pequenos e grandes poderiam abrigar populações viáveis, e em contexto de pouca mata remanescente, espécies sensíveis já teriam desaparecido. Com exceção da riqueza de espécies não-endêmicas, modelos que incluem o contexto foram as hipóteses mais plausíveis para descrever a variação da riqueza e abundância das espécies de pequenos mamíferos. Como esperado, a influência positiva da área do fragmento foi mais importante na paisagem com 30% de floresta para a maioria das espécies de pequenos mamíferos endêmicos, enquanto que os modelos que incluem a influência da área do fragmento não estiveram entre os mais plausíveis para as espécies não-endêmicas. Nossos resultados corroboram a existência de um limiar de fragmentação e indicam que, ainda que os limiares variem entre espécies, é possível identificar grupos com respostas semelhantes à perda e fragmentação do habitat, auxiliando as políticas de manejo e conservação. / A long-term standardized survey of the Atlantic Forest small mammals was conducted using pitfall traps in 68 sites distributed in six 10.000-ha landscapes (three in continuous forest and three in fragmented landscapes) located in three regions in the Atlantic Plateau of São Paulo. The fragmented landscapes harbored different amounts of remnants, 50%, 30% and 10%, percentages above or within the superior and inferior limits of the theoretical fragmentation threshold (10-30%). This thesis was divided in four chapters e two main approaches. The first approach (Chapter 2) aimed to evaluate if small mammals listed as threatened were affected by forest fragmentation and quality in the Atlantic Plateau of São Paulo state. For this, we used data from 68 sites distributed in eight categories: nine in mature continuous forests, nine in secondary continuous forests, four in large and 11 in small patches in the landscape with 50% of remnants, seven in large and 13 in small patches in the landscape with 30% of remnants and four in large and 11 in small patches in the landscape with 10% of remnants. We investigated if 10 threatened small mammals and five non-threatened endemic species commonly found in continuous forests were equally affected by fragmentation, at the landscape and patch scales, and by forest quality. Regardless of threat or rarity level, no analyzed species responded to differences in the regeneration stage in continuous forests. On the other hand, our data showed that common endemic species respond more strongly and negatively to the loss and fragmentation of the Atlantic Forest than threatened species, which either may not be affected by fragmentation, or be positively or negatively affected. we suggest separating species in two groups (naturally rare versus affected by human impact) in the Red Lists and including different criteria to evaluate common species such as response to habitat loss and fragmentation as well as habitat specificity in terms of endemism and level of matrix tolerance. The second approach (Chapter 3) aimed to evaluate the effects of context (landscape) and patch area in landscapes with different amounts of remnants on the richness and abundance of the endemic and non-endemic species. We used data from 50 sites located in the three fragmented landscapes. By analyzing the plausibility of eight regression models, which express alternative theoretical hypothesis about the importance of context and patch area, we investigate if the positive influence of patch area was stronger (1) for endemic species and (2) in the landscape within the superior limit of the fragmentation threshold (sensu Andrén, 1994), since in a context of high proportion of remnants, small and large patches could harbor viable populations and in a context of low proportion of remnants, sensitive species would have gone extinct. Except for the non116 endemic species richness, the models including context were the most plausible hypothesis to describe small mammal richness and abundance variations. As expected, the positive influence of patch area was more important in the landscape with 30% of remnants for the majority of the endemic small mammals, whereas the models including patch area were not among the most plausible ones for the non-endemic species. Our data corroborate the existence of a fragmentation threshold and point out that, although thresholds vary among species, it is possible to identify groups with similar response to habitat loss and fragmentation, directing management and conservation policies.

Orientador: Adriano Garcia Chiarello / Resumo: O efeito da redução do habitat natural na biodiversidade é idiossincrática a respeito das relações que se estabelecem entre as espécies e as características das paisagens modificadas pelo homem. Nesse contexto, as evidências científicas evidenciam cada vez mais a importância de se utilizar não somente a escala espacial na interpretação das respostas da biodiversidade, mas também a escala temporal. A correlação dos parâmetros biológicos atuais com características do ambiente pretérito mostra que respostas atrasadas das espécies às modificações podem ocorrer após um distúrbio ambiental, o que como consequência, gera interpretação errôneas da relação das espécies com os ambientes da paisagem no presente, o que vem a comprometer as subsequentes tomadas de decisão de viés conservacionista. A fim de compreender como espécies de mamíferos de médio e grande porte neotropicais estão respondendo à paisagens de Cerrado que passaram por redução de habitat ao longo de um intervalo temporal de 48 anos, a presente tese objetivou em seus capítulos: (i) caracterizar a trajetória e a transição das classes de cobertura e uso do solo de três paisagens modificadas pelo homem, (ii) Detectar a existência de respostas atrasadas de sete espécies de mamíferos neotropicais de médio e grande porte em relação ao ambiente nativo dessas três paisagens e (iii) detectar a existência de limiares ecológicos nas respostas de seis espécies de mamíferos neotropicais a ambientes nativo e antrópico. As três paisage... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The effect of habitat reduction on biodiversity is idiosyncratic regarding the established relationships among species and the traits of human-modified landscapes. In this manner novel scientific evidences point to the importance of considering not only the spatial scale on the interpretation of species responses, but also the temporal scale. The correlation between biological parameters of the present and environmental traits of the past show that species might present delayed responses after a disturbance event, and as consequence, species responses to current landscape traits may be misleading for conservation purposes and environmental management actions. In order to understand how the neotropical medium and large-sized mammals are responding to human-modified landscapes of Cerrado under a 48-years interval of disturbance, the present dissertation aimed in their three chapters: (i) to describe land use and land cover trajectory and native vegetation transition of three human-modified landscapes, (ii) to detect the existence of time-lagged responses among seven neotropical medium and large-sized mammal species to their the natural environment and (iii) to detect the existence of ecological threshold responses of six neotropical medium and large-sized mammal species to natural and human-modified environments. The three studied landscapes are located in the northeastern region of São Paulo State and harbor important protected remnants of Cerrado and Atlantic Rainforest under... (Complete abstract click electronic access below) / Doutor

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Pereira.pdf: 8559526 bytes, checksum: b0f6ba0982104d5a1057b1207b6f4c0e (MD5) Previous issue date: 2015-10-09 / FAPEAM - Fundação de Amparo à Pesquisa do Estado do Amazonas / The width of riparian zones and its conservation has been topic of discussion in political and scientific circles. The Brazilian Forest Code (BFC), which regulates creation of Permanent Protection Areas (PPA) prescribes protection of riparian vegetation up to 30 m on both stream sides. Studies conducted in Central Amazon showed that this width is not efficient in maintaining plant and animal biodiversity and ecosystem processes associated to them. We investigated the influence of distance to the stream on bat guild and species abundance, number and composition. We hypothesize that bat assemblage changes with distance to the stream. We believe that this change occurs at species composition level with increasing abundance, mainly of frugivorous and nectarivorous bats in areas close to streams. Bats were captured with mist-nets in 24 riparian plots and 25 non-riparian plots within a trail grid in a primary terra-firme forest at northeast of Manaus, Amazonas State, Brazil. Each plot was sampled thrice in 7056 net-hours. A total of 1.138 bats were captured, composing 51 species, five families and five trophic guilds. We used model selection by AIC (Akaike Information Criterion) in linear and piecewise regressions to estimate existence of ecological threshold for bat assemblage. For animalivorous and nectarivorous bat abundance, quantitative and qualitative species composition and guild composition, piecewise models with one breakpoint were more parsimonious and had greater Akaike weights than linear models. Animalivorous bat abundance was higher close to the stream up to 181 m and frugivorous bat abundance decreased up to 50 m of distance to the stream. The change on animalivorous bat abundance suggests that feeding areas away from streams may provide enough food to maintain more individuals of that guild and the opposite of that may occur for frugivorous bat abundance. The width of riparian zone recognized by bat species was up to 114 m of distance to the stream and was given by qualitative composition model. Given this width, requirements of 30 m for forest protection in riparian PPAs with streams of up to 10 m do not incorporate composition of bat species in riparian areas. Clearing of vegetation after 30 m allowed by law reduces 380% of riparian forest habitat that is necessary for conservation of bat assemblage in riparian zones. Ecological thresholds obtained from studies in primary forests at community level, combined with landscape descriptors suitable to animal and plant species ecology should be an effective strategy to predict width of riparian habitats necessary for biodiversity preservation. / A largura das zonas ripárias e sua conservação tem sido assunto de discussões no meio científico e político. O Código Florestal Brasileiro (CFB), que regulamenta a criação de Áreas de Proteção Permanente, determina a proteção de até 30 m de vegetação ripária em ambos os lados de pequenos riachos. Estudos realizados na Amazônia Central verificaram que esta largura não é eficiente em preservar a biodiversidade de alguns grupos animais e vegetais e processos ecossistêmicos associados a eles. Nós investigamos a influência da distância ao riacho sobre a abundância, número e composição de espécies e guildas tróficas de morcegos. A nossa hipótese é que a assembleia de morcegos muda com a distância ao riacho. Nós acreditamos que essa mudança se dê no nível de composição de espécies com o aumento da abundância, principalmente dos morcegos frugívoros e nectarívoros, nas áreas próximas aos riachos. Morcegos foram capturados com redes de neblina em 24 parcelas ripárias e 25 parcelas não-ripárias inseridas em uma grade de trilhas em uma floresta primária de terra firme a nordeste de Manaus, Estado do Amazonas, Brasil. Cada parcela foi amostrada três vezes, totalizando 7.056 horas-rede. Ao total foram capturados 1.138 morcegos, distribuídos em cinco famílias e 51 espécies, compondo cinco guildas tróficas. Utilizamos seleção de modelos por AIC (Akaike Information Criterion) nas regressões lineares e piecewise para estimar a existência de um limiar ecológico para a assembleia de morcegos. Para abundância de animalívoros e frugívoros, composição quantitativa e qualitativa de espécies e composição de guildas tróficas os modelos piecewise com um ponto de quebra foram mais parcimoniosos e tiveram maior peso do que os modelos lineares. A abundância dos morcegos animalívoros foi maior na região próxima ao riacho até 181 m e a abundância de morcegos frugívoros diminuiu até 50 m. Essa mudança na abundância de animalívoros sugere que áreas de forrageio mais afastadas do riacho devem fornecer alimento suficiente para manter maior número de indivíduos dessa guilda trófica e o inverso deve acontecer para os frugívoros. A largura da zona ripária reconhecida pelas espécies de morcegos foi de 114 m de distância ao riacho e foi dada pelo modelo de composição qualitativa. Considerando essa largura, as prescrições do CFB para proteção de 30 m de floresta em APP’s ripárias com riachos de até 10 m não incorporam a composição das espécies de morcegos de áreas ripárias. O desmatamento da vegetação depois de 30 m permitido pela legislação reduz 380% do habitat de floresta ripária necessário para a manutenção da assembleia de morcegos em zonas ripárias. Limiares ecológicos obtidos de estudos de comunidades em florestas primárias, combinados com descritores da paisagem apropriados à ecologia de espécies vegetais e animais devem constituir uma estratégia eficiente para prever a largura de habitats ripários necessária à preservação da biodiversidade.

Submitted by Renata Lopes (renatasil82@gmail.com) on 2016-07-25T11:29:35Z No. of bitstreams: 1 thiagorubiolidafonseca.pdf: 2521373 bytes, checksum: a24da2c1e7f75a55e9c0a3bb75fc040e (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2016-07-25T16:32:43Z (GMT) No. of bitstreams: 1 thiagorubiolidafonseca.pdf: 2521373 bytes, checksum: a24da2c1e7f75a55e9c0a3bb75fc040e (MD5) / Made available in DSpace on 2016-07-25T16:32:44Z (GMT). No. of bitstreams: 1 thiagorubiolidafonseca.pdf: 2521373 bytes, checksum: a24da2c1e7f75a55e9c0a3bb75fc040e (MD5) Previous issue date: 2016-03-29 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / As florestas urbanas estão inseridas em uma matriz altamente antropizada e fragmentada, resultando em comunidades com diferentes arranjos bióticos e estruturais. Uma das principais consequências dos impactos antrópicos, intensificados durante o Antropoceno, foi o surgimento dos Novel Ecosystems. Considerando a importância das florestas urbanas para a manutenção de serviços ecossistêmicos, conservação da biodiversidade, bem estar humano e sua relação com o conceito de Novel Ecosystems, três perguntas foram elaboradas: (1) Fragmentos florestais urbanos, localizados próximos entre si, apresentam diversidade, estrutura e composição de espécies semelhantes? (2) Fragmentos florestais urbanos apresentam composição, diversidade e estrutura distintas de uma floresta secundária em estágio avançado de regeneração, de mesma fitofisionomia na região? (3) Os fragmentos florestais urbanos estudados são exemplos de Novel Forests no Brasil? O estudo foi realizado no sudeste de Minas Gerais, em predomínio de Floresta Estacional Semidecidual Montana. Os indivíduos arbóreos (DAP ≥ 5 cm) de cinco fragmentos florestais urbanos e um fragmento florestal em estágio avançado de regeneração (controle) foram amostrados em 10 parcelas de 20 x 20 m. Os fragmentos urbanos se diferenciaram entre si com relação à diversidade e composição de espécies, devido à dominância de espécies exóticas (Pinus elliottii Engelm.) e nativas oportunistas (Eremanthus erythropappus (DC.) MacLeish). Os fragmentos urbanos se diferenciaram da floresta controle, apresentando composição de espécies distinta, baixa acumulação de biomassa, baixa diversidade e distribuição de espécies menos heterogênea, em sua maioria. A dominância de poucas espécies (exóticas ou nativas oportunistas) foi suficiente para indicar a ultrapassagem de um limiar ecológico, classificando-os como Novel Forests. Devido à atualidade do conceito e a escassez de trabalhos no Brasil, este estudo é importante para documentar a existência de Novel Forests em território brasileiro e contribuir para o conhecimento do seu funcionamento. / Urban forests are within a highly anthropogenic and fragmented matrix, resulting in communities with distinct biotic and structural assemblages. The most important consequence of human impacts, which was intensified in the Anthropocene, was the arise of Novel Ecosystems. Given the importance of urban forests to maintain ecosystem services, biodiversity conservation, human welfare and its relation with Novel Ecosystem concept, three questions were developed: (1) Diversity, structure and species composition are similar in urban forest fragments, located close together? (2) Species composition, diversity and structure of urban forest fragments are distinct from an old-growth forest located within the same phytophysiognomy and same region? (3) Are the studied urban forest fragments examples of brazilian Novel Forests? The study was conducted in the southeast of Minas Gerais State, within the seasonally semideciduous domain. Trees (DBH ≥ 5 centimeter) of five urban forest fragments and one old-growth forest fragment (control) were sampled with 10 plots of 20 x 20 m. The results showed that urban forest fragments were different mainly between diversity and species composition, due to the dominance of alien species (Pinus elliottii Engelm.) and native opportunists (Eremanthus erythropappus (DC.) MacLeish). The urban forest fragments were different from the control forest due to mostly different species composition, low biomass accumulation, low diversity, and less heterogeneous species distribution. The dominance of a few species (exotic or native opportunists) in most of the urban forest fragments was sufficient to indicate a crossed ecological threshold and define them as Novel Ecosystems. Due to the novelty of the concept and lack of studies in Brazil, this is important to show the existence of Brazilian Novel Forests and contribute to the knowledge of their function.