Rozprawy doktorskie: „Forest remnants”

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Masson, Peta Helen. "The dynamics of the Afromontane forest remnants in the Southwestern Cape". Master's thesis, University of Cape Town, 1990. http://hdl.handle.net/11427/21852.

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This thesis identifies the major forest types present in the southwestern Cape and investigates the floristic and structural changes in vegetation composition across the indigenous forest ecotone. The dynamics of forest-fynbos boundaries of differing post-fire age are compared and patterns of vegetation change from forest to fynbos are related to environmental constraints and disturbance history. Riparian forest and Scree forest were identified, and differences in the structure a.nd composition of the two forest types and their ecotonal communities were evident at both the recently burnt site of Swartboskloof and the fire-protected catchment of Orange · Kloof. Soil moisture, soil depth and the amount of rock cover were. key factors influencing the dynamics of the forest-fynbos ecdtone, with fbrest composition and the consequent availability of seed also important. The analysis of post-fire regeneration strategies indicated that seedling production and coppice growth were best represented in the igirnediate post-fire condition, thus supporting the initial floristic composition (IFC) hypothesis. This implies that coppice production is an immediate, reactionary mode of regeneration following disturbance, and that most seedling establishment and subsequent growth of saplings occurs soon after the disturbance event. The absence of seedlings in scree fynbos areas at Orange Kloof suggests an episodic recruitment strategy which is influenced by local species composition and seed production.

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Deakin, Elizabeth Louise. "Impacts of land-use intensification on forest remnants embedded within production landscapes". Thesis, University of Canterbury. Biological Sciences, 2013. http://hdl.handle.net/10092/8712.

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Agricultural expansion has transformed and fragmented natural forest habitats at an alarming rate, and dramatic increases in agricultural intensification have since taken place in order to keep pace with human population growth and food demands. This simultaneously poses a considerable threat to biodiversity in agricultural landscapes, as production land is now one of the largest terrestrial biomes on the planet. Therefore, its contribution to biodiversity conservation is critical. Links between the intensification of agricultural systems and ‘in situ’ declines of biodiversity on farmland have been well documented. However, despite growing recognition that system inputs such as fertiliser and livestock can move or ‘spillover’ into adjacent natural habitats, there has been no direct quantification of the extent of impacts in recipient ecosystems. These abiotic and biotic pathways can cause dramatic impacts on the diversity, composition, and functioning of remaining natural ecosystems, and on their ability to provide a variety of essential ecosystem services. Due to concerns regarding future food security, balancing trade-offs between agriculture and conservation has subsequently become a hot topic in ecological research. However, without any direct quantification of the off-site ecological impacts of agricultural intensification in mosaic landscapes, it is inherently difficult to fully evaluate strategies aimed at balancing production and conservation. Using New Zealand farming systems as a case study, this thesis aims to address gaps in our current understanding of how increasing agricultural intensification impacts biodiversity in native forest remnants embedded within production landscapes. The first main chapter explores whether the magnitude of ecological impact in forest remnants (for a suite of 26 response measures) and severity of edge effects, scale with the degree of land-use intensity in surrounding agricultural pastures. This chapter also examines whether ecological responses differ in remnants ‘spared’ for conservation purposes (i.e. where livestock are excluded by fencing). The second chapter uses a model food-chain approach native to New Zealand, to test whether nutrient spillover from agricultural pastures influences plant-herbivore and herbivore-parasitoid interactions in forest remnants. This chapter also includes a large-scale common garden fertilisation experiment using the same tri-trophic system, which was established to examine bottom-up multi-trophic responses to the independent and combined effects of Nitrogen (N), Phosphorus (P) and cow dung and urine. The third main chapter uses a novel stable isotope approach for quantifying community-wide incorporation of resources into trophic structure. I test for the first time whether increasing intensity of farming systems drives greater nutrient spillover spatially into adjacent forest remnant soils and examine scaling effects of 15N (as a marker for anthropogenic N) through multiple trophic levels. Beyond finding that agricultural land-use intensity generally has negative off-site effects on biodiversity, the key findings of this thesis were (i) spillover of nitrogen and phosphorus from agricultural systems into adjacent remnant soils is exacerbated by increases in land-use intensity, with (ii) percolating bottom-up effects on plant and insect community dynamics. (iii) The magnitude of ecological impacts in forest remnants scales linearly with increasing land-use intensity, as does (iv) direct anthropogenic N enrichment across multiple trophic levels, which has the potential to severely jeopardise the stability of ecologically important remnant habitats. (v) Although there were stark structural differences in remnants with and without livestock exclusion, impacts of land-use intensity on ecological response metrics were actually comparable across all sites. (vi) Livestock exclusion should be a priority first step towards conserving native forest remnants, however it should be recognised that fencing does not prevent abiotic channels of nutrient spillover (fertiliser drift, overland flow, leaching) in land characteristic of land spared for nature. (vii) Consequently, increasing land-use intensity compromises the effectiveness of the land-sparing trajectory for conserving native biodiversity, which is currently undertaken in New Zealand production systems. Given the overall strength of these findings and the novel, ecosystem-wide and landscape-scale approaches taken to address fundamental questions, the work in this thesis greatly enhances our knowledge of the relationships between agricultural productivity and ecological impacts in spatially-coupled ecosystems. This is highly important, not only in New Zealand but worldwide, as it is anticipated that unstoppable human population growth and food security pressures will cause ecological impacts both on the farm and in adjacent natural ecosystems to become even more severe. Therefore, determining the relationship between land-use intensification and biodiversity loss represents the cornerstone of sustainable agricultural development in the future.

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Barahona, Túpac A. "The impact of human practices on forest remnants people and conservation in a small nature reserve in western Nicaragua". Ohio : Ohio University, 2001. http://www.ohiolink.edu/etd/view.cgi?ohiou987449787.

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Rodrigues, Laís Lautenschlager. "Effects of domestic megafauna and landscape on diversity of mammals in Atlantic Forest remnants /". Rio Claro, 2019. http://hdl.handle.net/11449/191060.

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Orientador: Mauro Galetti Rodrigues
Resumo: A conversão de paisagens florestais para usos antrópicos é a principal causa do desmatamento das florestas tropicais em todo o mundo. Essas florestas são conhecidas por conter parte significativa da biodiversidade terrestre global, porém pouco se sabe sobre como as modificações na paisagem, como a perda de habitat para produção agropecuária e o principalmente o impacto do gado afetam a diversidade e ocupação de mamíferos resilientes nesses fragmentos. Sendo assim, nós examinamos como a riqueza de espécies e a composição de mamíferos são explicadas pela configuração da paisagem e como a presença do gado afeta a detecção de mamíferos de médio e grande porte. Foram amostradas 20 paisagens dominadas por pastagens ao longo de um gradiente de cobertura florestal (8% a 98%), no sudeste do Brasil. Nós registramos 75% das espécies de mamíferos esperadas para esta região em uma cobertura florestal de média a alta. A cobertura florestal, distância euclidiana do vizinho mais próximo e área estrutural foram as variáveis que melhor explicaram a ocorrência de algumas espécies de mamíferos dependentes de floresta. As comunidades de mamíferos exibiram um alto grau de alternação de espécies entre as paisagens, representando 95% da diversidade beta total. Os impactos da pecuária foram mostrados devido ao seu efeito negativo na detecção de espécies florestais e positivo na detecção de grupos de espécies não florestais. Discutimos a importância de manter fragmentos com alta cobertura vegetal para... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: The landscape conversion to anthropic uses is the major cause of deforestation worldwide. Tropical forests are known to contain a significant portion of global terrestrial biodiversity, but little is known about how changes in landscape, such as habitat loss for livestock and its impacts affect the diversity and occupation of resilient mammals in forest fragments immersed in pasture matrices. Here we examine how species richness and mammal composition are explained by landscape configuration and how cattle presence affects the detection of medium and large mammals. We sampled 20 landscapes dominated by pastures along a forest cover gradient (8% to 98%) in southeastern Brazil. We recorded 75% of the mammalian species expected for this region in a medium-to-high forest cover. Landscapes metrics, as forest cover, Euclidean distance from the nearest neighbor and structural area were the variables that best explained the occurrence of some forest mammal species. Mammalian communities exhibited a high degree of species turnover between landscapes, representing 95% of total beta diversity. Livestock impacts were shown due to its negative effect on the detection of forest-dwelling species and positive on the detection of non-forest species groups. We discuss the importance of maintaining forest fragments with high vegetation cover to improve connectivity between disturbed landscapes, favoring mammalian species flow. There is an urgent need for a better understanding of livestock gene... (Complete abstract click electronic access below)
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Dufner, Karina Campos Tisovec. "Intention of preserving forest remnants among landowners in the Atlantic Forest: the role of the ecological context and experiences with nature". Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/41/41134/tde-20092018-103043/.

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Unravelling the psychological processes determining landowners\' support towards forest conservation is key, particularly, in developing countries, where most forest remnants are within private lands. As human-nature connections are known to shape pro-environmental behaviors, the intention of preserving forest remnants should be ultimately determined by the ecological context people live in. Here, we investigate the pathways through which the ecological context (forest cover), via experiences with nature (contact, uses and losses associated with forests), influences the psychological determinants of conservation behavior (beliefs, attitude and intention towards preserving forest remnants). We conceptualized a model based on the Reasoned Action Approach, using the ecological context and experiences with nature as background factors, and tested the model using Piecewise SEM. Data was collected through an interview-based protocol applied to 106 landowners across 13 landscapes varying in forest cover in a region in the Brazilian Atlantic Forest. Our results indicate that: (i) ecosystem services are more important than disservices for shaping intention of preserving forests, particularly those related to non-provisioning benefits; (ii) contact with forest has an indirect effect on intention, by positively influencing forest uses; (iii) people living in more forested ecological contexts have more experiences with nature, and ultimately stronger intention of preserving forests. Hence, our study suggests a dangerous positive feedback loop between deforestation and the extinction of human-nature connections. Local demands across the full range of ecosystem services, the balance between services and disservices, and the ecological context people live should be considered when developing conservation initiatives in rural areas
Desvendar os processos psicológicos que determinam o apoio dos proprietários de terras à conservação das florestas é fundamental, particularmente, nos países em desenvolvimento, onde a maioria dos remanescentes florestais se encontra em áreas privadas. Como as conexões humano-natureza são conhecidas por moldar comportamentos pró-ambientais, a intenção de preservar remanescentes florestais deve ser, em última instância, determinada pelo contexto ecológico no qual as pessoas vivem. Neste trabalho, investigamos os caminhos pelos quais o contexto ecológico (cobertura florestal), através das experiências com a natureza (contato, usos e perdas associados às florestas), influencia os determinantes psicológicos do comportamento de conservação (crenças, atitude e intenção de preservar remanescentes florestais). Formulamos um modelo baseado na Abordagem da Ação Racional, usando o contexto ecológico e as experiências com a natureza como fatores de base, e o testamos através da Piecewise SEM. Os dados foram coletados através de protocolo aplicado, por meio de entrevista, a 106 proprietários de terra em 13 paisagens que variam em cobertura florestal em uma região da Mata Atlântica. Nossos resultados indicam que: (i) serviços ecossistêmicos são mais importantes que desserviços para moldar a intenção de preservar florestas, particularmente outros serviços que não os de provisão; (ii) o contato com a floresta tem um efeito indireto sobre a intenção, influenciando positivamente os usos da floresta; (iii) as pessoas que vivem em contextos ecológicos mais florestados têm mais experiências com a natureza e, assim, uma intenção mais forte de preservar as florestas. Nosso estudo, portanto, sugere um perigoso ciclo de retroalimentação positiva entre o desmatamento e a extinção das conexões humano-natureza. As demandas locais considerando toda a gama de serviços ecossistêmicos, o balanço entre serviços e desserviços e o contexto ecológico no qual as pessoas vivem devem ser considerados ao se desenvolverem iniciativas de conservação em áreas rurais

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Barahona, Tupac A. "THE IMPACT OF HUMAN PRACTICES ON FOREST REMNANTS: PEOPLE AND CONSERVATION IN A SMALL NATURE RESERVE IN WESTERN NICARAGUA". Ohio University / OhioLINK, 2001. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou987449787.

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Hausmann, Franziska, i n/a. "The Utility of Linear Riparian Rainforest for Vertebrates on the Atherton and Evelyn Tablelands, North Queensland". Griffith University. Australian School of Environmental Studies, 2004. http://www4.gu.edu.au:8080/adt-root/public/adt-QGU20050115.105740.

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This study investigated the utility to vertebrates of upland linear riparian rainforest fragments on the Atherton and Evelyn Tablelands in the Australian Wet Tropics region, north Queensland. Similar linear fragments were selected, that varied in forest age and their connectivity to large areas of continuous forest:- (connected primary (N=6), isolated primary (N=5), connected secondary (N=6) and isolated secondary (N=7)). Primary sites had either never been cleared or only subject to selective logging, while secondary forest had been completely cleared and allowed to regenerate for at least 30 years. These linear fragments were contrasted with riparian sites within continuous forest sites (N=6 to 7), which were situated in State Forest or National Parks, and sites within the cleared matrix (pasture, N=6). Vertebrates surveyed were birds, ground-dwelling mammals and reptiles, particularly leaf-litter skinks. All surveys were conducted between September and December in 2001 and/or 2000. Chapter 2 investigates the effects of forest age, isolation and structural vegetation features on bird assemblages within linear riparian fragments of rainforest. Bird surveys and structural vegetation assessments were conducted within connected and isolated primary and secondary linear fragments, and compared with those of continuous forest habitat (N=6) and pasture. There were strong effects of forest age; all three types of primary rainforest had higher values than secondary rainforest for most measured attributes of vegetation structure (including canopy height and cover; and frequency of large-diameter trees, lianes, epiphytes, strangler figs; and woody debris), but lower frequencies of tree ferns and thorny scramblers. Sites within primary rainforest also had a greater frequency of many bird species across different guilds of habitat, feeding and movement. Assemblages of rainforest-dependent birds showed an effect of isolation, although its strength was less than that of forest age. Isolated fragments of primary rainforest differed significantly from continuous primary rainforest in their rainforest-dependent bird species assemblages (and had lower species richness), and isolated fragments of secondary rainforest differed from those that were connected. There was a significant association between the species composition of rainforest birds and some measured vegetation parameters across all sites, but not within primary or secondary sites. Vegetation differences did not explain the lowered frequency of several species in isolated fragments. Limited dispersal seems unlikely to be a main cause, and causal processes probably vary among species. Specialist rainforest species endemic to the Wet Tropics region showed stronger responses to present-day rainforest age and fragmentation than those not endemic. Variation in nest depredation levels associated with rainforest fragmentation (edge effects) is examined in Chapter 3. Artificial nests were placed in the forest understorey at seven edge sites where continuous forest adjoined pasture, seven interiors (about one kilometre from the edge), and six primary linear riparian forest remnants (50-100 m wide) that were connected to continuous forest. Four nest types were compared, representing different combinations of two factors; height (ground, shrub) and shape (open, domed). At each site, four nests of each type, containing one quail egg and two model plasticine eggs, were interspersed about 15 m apart within a 160 m transect. Predators were identified from marks on the plasticine eggs. The overall depredation rate was 66.5% of 320 nests' contents damaged over a three-day period. Large rodents, especially the rat Uromys caudimaculatus, and birds, especially the spotted catbird Ailuroedus melanotis, were the main predators. Mammals comprised 56.5% and birds 31.0% of identified predators, with 12.5% of unknown identity. The depredation rate did not vary among site-types, or between open and domed nests, and there were no statistically significant interactions. Nest height strongly affected depredation rates by particular types of predator; depredation rates by mammals were highest at ground nests, whereas attacks by birds were most frequent at shrub nests. These effects counterbalanced so that overall there was little net effect of nest height. Mammals accounted for 78.4% of depredated ground nests and birds for at least 47.4% of shrub nests (and possibly up to 70.1%). The main predators were species characteristic of rainforest, rather than habitat generalists, open-country or edge specialists. For birds that nest in the tropical rainforest understorey of the study region, it is unlikely that edges and linear remnants presently function as ecological population sinks due to mortality associated with increased nest depredation. The use of linear riparian remnants by small ground-dwelling mammals and reptiles (mainly leaf litter skinks), is reported in Chapter 4. Site types were continuous rainforest, connected and isolated linear fragments of both uncleared primary rainforest and secondary regrowth rainforest. Mammals were also surveyed in pasture sites. Neither reptile species richness nor abundance varied significantly among site types. Although mammal species richness varied significantly between site types, with isolated primary sites containing highest species richness, overall mammal abundance did not differ significantly among site types. Pasture sites differed significantly from all rainforest sites in their mammal species composition, and were dominated by the introduced house mouse (Mus musculus). This species was absent from all rainforest sites, which were characterised by moderate abundances of bush rat/Cape York rat Rattus fuscipes/leucopus, fawn-footed melomys Melomys cervinipes and giant white-tailed rat Uromys caudimaculatus. None of these species varied significantly in abundance among site types, although the giant white-tailed rat showed a trend (P=0.09) for reduced abundance in isolated secondary sites. A single reptile species, the prickly forest skink Gnypetoscincus queenslandiae, occurred in sufficient numbers for individual analysis, and its abundance varied significantly among the forested site types, being less abundant in all linear fragments than in continuous forest sites. The utility of linear riparian rainforest for vertebrates appears to be species-specific and involves many factors. However, overall, species endemic to the Wet Tropics (which are hence of the highest conservation significance) appear to be the most sensitive to fragmentation. These species were most likely to show altered abundances or frequencies of occurrence due to isolation, forest age, and habitat linearity. The ecology of species within this group warrants further investigation within fragmented and non-fragmented regions of the Tablelands. For many other vertebrates examined in this study, there appears to be sufficient functional connectedness between remnants on the Tablelands to minimise the effects of fragmentation. Nevertheless, the lower density of many of these species in pasture may indicate that their long-term persistence within the fragmented rainforest areas could benefit from the maintenance or establishment of habitat linkages. Certainly, if the current rainforest vegetation cover were further reduced, or if the land use in the matrix became more intensive, the establishment of specific habitat linkages could become more important as existing dispersal routes could be lost. It also appears that nest depredation levels are unlikely to limit the value of linear rainforest remnants and other small rainforest remnants as breeding habitat for birds (at least for understorey-nesting species), relative to more intact rainforest, in the study region.

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Jay, Grace Mairi McIntyre. "Symbolic order and material agency a cultural ecology of native forest remnants on Waikato dairy farms /". Connect to this title online, 2004. http://adt.waikato.ac.nz/public/adt-uow20060125.120921/.

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Jay, Grace Mairi M. "Symbolic order and material agency: A cultural ecology of native forest remnants on Waikato dairy farms". The University of Waikato, 2004. http://hdl.handle.net/10289/2603.

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Loss of native biological diversity is a world-wide problem of growing international concern. One of the main causes of native biodiversity loss is destruction and degradation of native habitat through land development for agriculture. The Waikato region is an example of the destruction and degradation of native habitat in association with the development and intensification of farming, including dairy farming. This thesis explores cultural reasons for the loss of native forest in the Waikato region, and reasons why fragments of native forest remain. The research involves a participant observation study of 'typical' dairy farm families for 9 months of the dairy year, in-depth interviews of dairy farmers who have protected a significant proportion of their land for conservation of native habitat, a questionnaire of dairy farmers, and an examination of dairy farm magazines and other literature to identify the values and attitudes that motivate dairy farmers in relation to land management and protection of native habitat. The title of the thesis suggests two elements that are important for understanding the loss and persistence of native forest in Waikato's farmed landscapes. Symbolic reason refers to the values, attitudes and perceptions of farmers that derive from socio-political and economic forces which encourage productivist practises that leave little opportunity for native forest to survive. Material agency refers to the local circumstances of particular farms and individual people which enable native forest to persist. The thesis argues that persistence of native forest depends on the idiosyncrasies of material circumstance in the face of relentless pressure to transform the production landscape for economic purposes. The thesis concludes with a suggestion that policies to assist survival of native habitat in farmed landscapes need to include ones that encourage the odds in favour of fortuitous circumstance. In the face of globalised economic pressures, policies for conservation of native biodiversity need to involve a 'portfolio' of measures that apply to individual landowners and the wider rural community by recognising, assisting and rewarding management for non-production values.

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Tariku, Haile Yineger. "Comparing Bird Communities and a Forest Tree in Fragmented Remnants in NW Ethiopia: Inventory, Conservation Planning, Modelling and Conservation Genetic Approaches". Thesis, Griffith University, 2014. http://hdl.handle.net/10072/367874.

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Anthropogenic disturbance regimes in areas that were once large continuous habitats have been major drivers of habitat fragmentation and loss which in turn form the largest worldwide threat to biodiversity. Studies suggest that functional trait based approaches provide better understanding of fragmentation effects on ecological processes in human- modified landscapes. However, research on these thematic areas is limited in many tropical regions, such as Ethiopia. In the second chapter of this thesis, I evaluated sensitivity of bird communities and functional groups to fragmentation processes in Ethiopia. Standard point counts were used to survey birds in 16 remnant forest patches of variable sizes and degrees of isolation. The information theoretic model selection approach was used for precise understanding of avian functional group responses to habitat loss and fragmentation. Results showed strong impacts of forest loss and fragmentation on forest specialists, insectivores, frugivores, open nesters, understorey nesters and resident birds. These results led to the identification of indicator bird functional groups, which can be used to prioritize sites for conservation particularly where management funds are limited. Specifically, the indicator groups can provide the cheapest option to efficiently conserve biodiversity of the region particularly when systematic conservation planning approaches are used while at the same time considering important landscape features, socio-economic, political and bioclimatic factors. Where management resources are affordable, protection and restoration of the remnant forest patches and matrix vegetation may help mitigate the negative effects of fragmentation on the specialist bird functional groups.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
Griffith School of Environment
Science, Environment, Engineering and Technology
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Santos, Carlos Eduardo de Santana. "A expansão urbana sobre os remansecentes florestais situados no entorno da Avenida Luis Viana Filho, Salvador - Bahia". reponame:Repositório Institucional da UFBA, 2009. http://www.repositorio.ufba.br/ri/handle/ri/9706.

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Com o acelerado processo de expansão urbana, o conjunto da vegetação natural contido nas grandes cidades vem sofrendo, a cada ano, significativas reduções. Em Salvador, os remanescentes de vegetação natural foram drasticamente reduzidos e em algumas áreas do município a floresta urbana é completamente ausente. Atualmente a maior parte destas se encontra em áreas da cidade protegida pelo poder público. A área de estudo abriga um dos últimos remanescentes florestais de grande porte em propriedade particular no município de Salvador. Inserida entre as regiões Administrativas de Itapuã (RA X) e Pau da Lima (RA XIII) é recortada transversalmente por uma das mais importantes avenidas de Salvador, a Av. Luis Viana Filho. Sofre intensa pressão por ocupação, tanto por parte de movimentos populares, quanto por pelo capital imobiliário. É neste cenário que o presente trabalho objetiva mensurar os impactos da expansão urbana frente aos remanescentes florestais, nos períodos de 1989 – 2002 – 2006. O programa de geoprocessamento ArcView versão 3.3 foi escolhido para o desenvolvimento do trabalho. Fotos aéreas da área de estudo foram digitalizadas e georreferenciadas para posterior composição de um fotomosaico. O programa de geoprocessamento permitiu a delimitação de ilhas de vegetação sobre as fotos digitalizadas. Esta operação foi feita para todos os mosaicos de imagem nos períodos estudados. Para uma melhor classificação dos fragmentos e uma análise mais detalhada do objeto de estudo foi realizada uma subdivisão da área estudada. Assim, foram criadas as sub-áreas Nordeste, Noroeste e Sul. Uma vez encerrada a fotointerpretação, as feições foram classificadas e conferidas nos três períodos estudados. Os dados referentes à área e à classificação das tipologias foram sistematizados em um banco de dados para posterior análise. Por fim, os mapas resultantes da classificação foram elaborados, de forma a auxiliar na análise da evolução urbana nos períodos pré-estabelecidos. O cenário atual da área de estudo é de constante transformação, onde tem ocorrido uma rápida conversão dos remanescentes florestais e áreas úmidas para ambiente construído. Em 17 anos, a área urbanizada contida na poligonal em estudo aumentou em 12,42 % no período compreendido entre os anos de 1989 a 2006, ao passo que as áreas de remanescentes florestais recuaram 11,41 %. Em termos absolutos, no intervalo temporal total (1989 a 2002) foram perdidos 247 hectares de floresta ombrófila densa, dos quais 115 hectares em estágio médio e 132 hectares em estágio inicial. Na totalidade do intervalo temporal avaliado, a tipologia que apresentou maior retração na área estudada foi a floresta Ombrófila em Estágio inicial, com uma taxa de decréscimo de 7,8 hectares ao ano (ha/ano).
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Vianna, Renata Marques [UNESP]. "Assembleia de aves comparada em dois fragmentos de floresta estacional semidecidual do centro oeste paulista". Universidade Estadual Paulista (UNESP), 2017. http://hdl.handle.net/11449/151360.

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Devido ao desmatamento e perda de área, a Mata Atlântica e suas fisionomias têm sido alvo de diversos estudos sobre as comunidades de aves em diversos fragmentos. O atual estudo visou registrar a riqueza de aves presentes em dois fragmentos de mata estacional semidecidual: a RNNP Olavo Egydio Setúbal (OES) com 615 ha e no fragmento pertencente à fazenda Igurê (IGR) com 320 ha. Além da análise e comparação da estrutura da avifauna nos dois fragmentos a partir de dados como riqueza e abundância, foram também comparadas as categorias alimentares e estratos de forrageio em relação às riquezas e abundâncias registradas em estudos conduzidos anteriormente nas mesmas áreas. Os levantamentos foram realizados mensalmente em cada fragmento durante um período de 12 meses por meio da metodologia de pontos de contagem. Foi registrado um total 129 espécies de aves nas áreas de estudo, sendo 102 espécies em cada fragmento. Os índices de diversidade e equidistribuição apresentaram-se ligeiramente maiores na OES; ambos locais apresentaram maiores riquezas de espécies insetívoras seguidas por frugívoras; quanto às abundâncias, espécies insetívoras foram mais abundantes nos dois locais, porém, as espécies onívoras apresentaram uma maior abundância em relação a OES. Nos dois fragmentos foram registradas espécies endêmicas da Mata Atlântica e ameaçadas de extinção, sendo na OES 22 espécies endêmicas e duas ameaçadas e na IGR 16 endêmicas e duas ameaçadas. A comparação com estudos anteriores revelou que as espécies que apresentaram maiores alterações possuem maior especificidade alimentar como insetívoros e frugívoros. Mesmo apresentando a mesma riqueza, as duas áreas possuem composições específicas distintas, sendo mais espécies de aves especialistas encontradas na OES e na IGR mais espécies generalistas. Apesar de estarem expostas a diferentes pressões, as duas áreas de estudo são de grande importância para a manutenção da avifauna do interior paulista, apresentando a capacidade de manter espécies endêmicas da Mata Atlântica e ameaçadas de extinção cujos níveis de sensibilidade muitas vezes não toleram fragmentos alterados.
Due to deforestation and loss of area, the Atlantic Forest and its physiognomies have been the target of several studies on the bird communities in several fragments. The present study aimed to record the richness of birds present in two fragments of semideciduous seasonal forest: Olavo Egydio Setúbal (OES) with 615 ha and in the Igurê farm (IGR) with 320 ha. In addition to analyze and compare the structure of the avifauna in the two fragments from data such as richness and abundance, we also compared the food categories and forage strata in relation to the richness and abundance recorded in studies conducted previously in the same areas. The surveys were carried out monthly in each fragment during a period of 12 months using the methodology of counting points. A total of 129 bird species were recorded in the study areas, with 102 species in each fragment. The diversity and evenness indexes were slightly higher in OES; both sites presented higher richness of insectivorous species followed by frugivores; insectivorous species were more abundant in both sites, however, the omnivorous species in IGR presented a higher abundance in relation to OES. In both fragments endemic species of the Atlantic Forest and threatened with extinction were recorded, being in OES 22 endemic species and two endangered species and in IGR 16 endemic and two threatened. Comparison with previous studies revealed that the species that presented the greatest changes have a higher food specificity such as insectivores and frugivores. Even though they present the same richness, the two areas have distinct specific compositions, with more species of specialized birds found in the OES and in IGR a higher number of generalist species. Although they are exposed to different pressures, these two study areas are of great importance for the maintenance of avifauna in the interior of São Paulo, presenting the capacity to maintain endemic endangered Atlantic Forest species whose levels of sensitivity often do not tolerate altered fragments.

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Hutchison, Melissa Alice Sarah. "Interactions between habitat fragmentation and invasions: factors driving exotic plant invasions in native forest remnants, West Coast, New Zealand". Thesis, University of Canterbury. School of Biological Sciences, 2009. http://hdl.handle.net/10092/3218.

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Habitat fragmentation and biological invasions are widely considered to be the most significant threats to global biodiversity, and synergistic interactions between these processes have the potential to cause even greater biodiversity loss than either acting alone. The objective of my study was to investigate the effects of fragmentation on plant communities in native forest fragments, and to examine potential interactions between these effects and invasions by exotic plants at multiple spatial scales. I examined edge, area and landscape effects on plant invasions using empirical data from fragmented landscapes on the West Coast of New Zealand. My research revealed significant interactions between the amount of native forest cover in the landscape and the strength of edge and area effects on plant communities in forest fragments. The dominance of exotic plants in the community was highest at forest edges and decreased towards fragment interiors, however the interiors of very small fragments were relatively more invaded by exotic plants than those in larger fragments, reflecting a significant interaction between edge and area effects. Similarly, exotic dominance increased in more heavily deforested landscapes, but this effect was only apparent in very small fragments (<2 ha). The combined effects of small fragment size and low forest cover in the landscape appear to have promoted invasions of exotic plants in very small remnants. I explored the mechanisms underlying edge-mediated invasions in forest fragments and examined whether propagule availability and/or habitat suitability may be limiting invasions into fragments. Experimental addition of exotic plant propagules revealed that landscape forest cover interacted with edge effects on germination, growth and flowering rates of two short-lived, herbaceous species, and this appeared to be driven by elevated light and soil phosphorus levels at edges in heavily deforested landscapes. I also examined the role of traits in influencing plant responses to forest fragmentation. Different traits were associated with exotic invasiveness in edge and interior habitats of forest fragments, indicating that the traits promoting invasiveness were context dependent. Traits also had a major influence on responses of native plants to forest fragmentation, with generalist species appearing to benefit from fragmentation, as they can utilise both forest and open habitats, whereas native forest specialists have been negatively impacted by fragmentation.

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Vianna, Renata Marques. "Assembleia de aves comparada em dois fragmentos de floresta estacional semidecidual do centro oeste paulista". Botucatu, 2017. http://hdl.handle.net/11449/151360.

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Orientador: Reginaldo José Donatelli
Resumo: Devido ao desmatamento e perda de área, a Mata Atlântica e suas fisionomias têm sido alvo de diversos estudos sobre as comunidades de aves em diversos fragmentos. O atual estudo visou registrar a riqueza de aves presentes em dois fragmentos de mata estacional semidecidual: a RNNP Olavo Egydio Setúbal (OES) com 615 ha e no fragmento pertencente à fazenda Igurê (IGR) com 320 ha. Além da análise e comparação da estrutura da avifauna nos dois fragmentos a partir de dados como riqueza e abundância, foram também comparadas as categorias alimentares e estratos de forrageio em relação às riquezas e abundâncias registradas em estudos conduzidos anteriormente nas mesmas áreas. Os levantamentos foram realizados mensalmente em cada fragmento durante um período de 12 meses por meio da metodologia de pontos de contagem. Foi registrado um total 129 espécies de aves nas áreas de estudo, sendo 102 espécies em cada fragmento. Os índices de diversidade e equidistribuição apresentaram-se ligeiramente maiores na OES; ambos locais apresentaram maiores riquezas de espécies insetívoras seguidas por frugívoras; quanto às abundâncias, espécies insetívoras foram mais abundantes nos dois locais, porém, as espécies onívoras apresentaram uma maior abundância em relação a OES. Nos dois fragmentos foram registradas espécies endêmicas da Mata Atlântica e ameaçadas de extinção, sendo na OES 22 espécies endêmicas e duas ameaçadas e na IGR 16 endêmicas e duas ameaçadas. A comparação com estudos anteriores revel... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: Due to deforestation and loss of area, the Atlantic Forest and its physiognomies have been the target of several studies on the bird communities in several fragments. The present study aimed to record the richness of birds present in two fragments of semideciduous seasonal forest: Olavo Egydio Setúbal (OES) with 615 ha and in the Igurê farm (IGR) with 320 ha. In addition to analyze and compare the structure of the avifauna in the two fragments from data such as richness and abundance, we also compared the food categories and forage strata in relation to the richness and abundance recorded in studies conducted previously in the same areas. The surveys were carried out monthly in each fragment during a period of 12 months using the methodology of counting points. A total of 129 bird species were recorded in the study areas, with 102 species in each fragment. The diversity and evenness indexes were slightly higher in OES; both sites presented higher richness of insectivorous species followed by frugivores; insectivorous species were more abundant in both sites, however, the omnivorous species in IGR presented a higher abundance in relation to OES. In both fragments endemic species of the Atlantic Forest and threatened with extinction were recorded, being in OES 22 endemic species and two endangered species and in IGR 16 endemic and two threatened. Comparison with previous studies revealed that the species that presented the greatest changes have a higher food specificity such as... (Complete abstract click electronic access below)
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Hausmann, Franziska. "The Utility of Linear Riparian Rainforest for Vertebrates on the Atherton and Evelyn Tablelands, North Queensland". Thesis, Griffith University, 2004. http://hdl.handle.net/10072/365964.

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This study investigated the utility to vertebrates of upland linear riparian rainforest fragments on the Atherton and Evelyn Tablelands in the Australian Wet Tropics region, north Queensland. Similar linear fragments were selected, that varied in forest age and their connectivity to large areas of continuous forest:- (connected primary (N=6), isolated primary (N=5), connected secondary (N=6) and isolated secondary (N=7)). Primary sites had either never been cleared or only subject to selective logging, while secondary forest had been completely cleared and allowed to regenerate for at least 30 years. These linear fragments were contrasted with riparian sites within continuous forest sites (N=6 to 7), which were situated in State Forest or National Parks, and sites within the cleared matrix (pasture, N=6). Vertebrates surveyed were birds, ground-dwelling mammals and reptiles, particularly leaf-litter skinks. All surveys were conducted between September and December in 2001 and/or 2000. Chapter 2 investigates the effects of forest age, isolation and structural vegetation features on bird assemblages within linear riparian fragments of rainforest. Bird surveys and structural vegetation assessments were conducted within connected and isolated primary and secondary linear fragments, and compared with those of continuous forest habitat (N=6) and pasture. There were strong effects of forest age; all three types of primary rainforest had higher values than secondary rainforest for most measured attributes of vegetation structure (including canopy height and cover; and frequency of large-diameter trees, lianes, epiphytes, strangler figs; and woody debris), but lower frequencies of tree ferns and thorny scramblers. Sites within primary rainforest also had a greater frequency of many bird species across different guilds of habitat, feeding and movement. Assemblages of rainforest-dependent birds showed an effect of isolation, although its strength was less than that of forest age. Isolated fragments of primary rainforest differed significantly from continuous primary rainforest in their rainforest-dependent bird species assemblages (and had lower species richness), and isolated fragments of secondary rainforest differed from those that were connected. There was a significant association between the species composition of rainforest birds and some measured vegetation parameters across all sites, but not within primary or secondary sites. Vegetation differences did not explain the lowered frequency of several species in isolated fragments. Limited dispersal seems unlikely to be a main cause, and causal processes probably vary among species. Specialist rainforest species endemic to the Wet Tropics region showed stronger responses to present-day rainforest age and fragmentation than those not endemic. Variation in nest depredation levels associated with rainforest fragmentation (edge effects) is examined in Chapter 3. Artificial nests were placed in the forest understorey at seven edge sites where continuous forest adjoined pasture, seven interiors (about one kilometre from the edge), and six primary linear riparian forest remnants (50-100 m wide) that were connected to continuous forest. Four nest types were compared, representing different combinations of two factors; height (ground, shrub) and shape (open, domed). At each site, four nests of each type, containing one quail egg and two model plasticine eggs, were interspersed about 15 m apart within a 160 m transect. Predators were identified from marks on the plasticine eggs. The overall depredation rate was 66.5% of 320 nests' contents damaged over a three-day period. Large rodents, especially the rat Uromys caudimaculatus, and birds, especially the spotted catbird Ailuroedus melanotis, were the main predators. Mammals comprised 56.5% and birds 31.0% of identified predators, with 12.5% of unknown identity. The depredation rate did not vary among site-types, or between open and domed nests, and there were no statistically significant interactions. Nest height strongly affected depredation rates by particular types of predator; depredation rates by mammals were highest at ground nests, whereas attacks by birds were most frequent at shrub nests. These effects counterbalanced so that overall there was little net effect of nest height. Mammals accounted for 78.4% of depredated ground nests and birds for at least 47.4% of shrub nests (and possibly up to 70.1%). The main predators were species characteristic of rainforest, rather than habitat generalists, open-country or edge specialists. For birds that nest in the tropical rainforest understorey of the study region, it is unlikely that edges and linear remnants presently function as ecological population sinks due to mortality associated with increased nest depredation. The use of linear riparian remnants by small ground-dwelling mammals and reptiles (mainly leaf litter skinks), is reported in Chapter 4. Site types were continuous rainforest, connected and isolated linear fragments of both uncleared primary rainforest and secondary regrowth rainforest. Mammals were also surveyed in pasture sites. Neither reptile species richness nor abundance varied significantly among site types. Although mammal species richness varied significantly between site types, with isolated primary sites containing highest species richness, overall mammal abundance did not differ significantly among site types. Pasture sites differed significantly from all rainforest sites in their mammal species composition, and were dominated by the introduced house mouse (Mus musculus). This species was absent from all rainforest sites, which were characterised by moderate abundances of bush rat/Cape York rat Rattus fuscipes/leucopus, fawn-footed melomys Melomys cervinipes and giant white-tailed rat Uromys caudimaculatus. None of these species varied significantly in abundance among site types, although the giant white-tailed rat showed a trend (P=0.09) for reduced abundance in isolated secondary sites. A single reptile species, the prickly forest skink Gnypetoscincus queenslandiae, occurred in sufficient numbers for individual analysis, and its abundance varied significantly among the forested site types, being less abundant in all linear fragments than in continuous forest sites. The utility of linear riparian rainforest for vertebrates appears to be species-specific and involves many factors. However, overall, species endemic to the Wet Tropics (which are hence of the highest conservation significance) appear to be the most sensitive to fragmentation. These species were most likely to show altered abundances or frequencies of occurrence due to isolation, forest age, and habitat linearity. The ecology of species within this group warrants further investigation within fragmented and non-fragmented regions of the Tablelands. For many other vertebrates examined in this study, there appears to be sufficient functional connectedness between remnants on the Tablelands to minimise the effects of fragmentation. Nevertheless, the lower density of many of these species in pasture may indicate that their long-term persistence within the fragmented rainforest areas could benefit from the maintenance or establishment of habitat linkages. Certainly, if the current rainforest vegetation cover were further reduced, or if the land use in the matrix became more intensive, the establishment of specific habitat linkages could become more important as existing dispersal routes could be lost. It also appears that nest depredation levels are unlikely to limit the value of linear rainforest remnants and other small rainforest remnants as breeding habitat for birds (at least for understorey-nesting species), relative to more intact rainforest, in the study region
Thesis (Masters)
Master of Philosophy (MPhil)
Australian School of Environmental Studies
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Brassaloti, Ricardo Augusto. "Diversidade e estrutura de taxocenoses de anfíbios anuros em uma paisagem fragmentada no centro-oeste paulista /". São José do Rio Preto : [s.n.], 2010. http://hdl.handle.net/11449/87615.

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Orientador: Denise de Cerqueira Rossa-Feres
Banca: Lilian Casatti
Banca: Cynthia Peralta de Almeida Prado
Resumo: Anfíbios anuros são particularmente sensíveis a alterações no habitat, seja pela sua baixa vagilidade e fidelidade a áreas de reprodução e forrageio, ou mesmo, por possuírem ciclo de vida complexo com fase aquática e terrestre. Tais características os tornam bons modelos para o estudo de questões relacionadas à modificação no habitat, sejam elas relativas a identificação de padrões ou inferência sobre processos associados à fragmentação ou perda de habitat original ou mesmo ocupação e colonização em áreas alteradas. Dentro deste contexto, este trabalho procurou como objetivo principal, determinar a diversidade e estrutura da taxocenose de anfíbios anuros presente em remanescentes de floresta estacional semidecidual (FES) e compará-la com a registrada em implantações silviculturais, na região centro-oeste do estado de São Paulo (capítulo 3). Além deste, buscou-se o levantamento da fauna em uma área preservada (Unidade de Conservação), afim de aproximar-se da composição presente na região antes do processo de fragmentação (capítulo 1), além da distribuição espacial das espécies encontradas nesse tipo de formação florestal (FES) e sua possível relação biogeográfica com taxocenoses presentes nas fitofisionomias limítrofes a ela (capítulo 2). A partir do levantamento mensal das espécies em campo durante nove meses consecutivos, compreendidos na estação de maior atividade para o grupo, e utilizando-se de metodologias diferentes e complementares (armadilhas de interceptação e queda e procura em ambientes de reprodução), foram determinadas a abundância e a riqueza de anuros em três áreas comparáveis de implantação florestal (silvicultura de eucalipto) e três remanescentes florestais (fragmentos de FES), além da única grande unidade de conservação em um raio de 150 km... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: Frogs are particularly sensitive to changes in habitat, either by their low vagility and fidelity to breeding and foraging sites, or even by had a complex life cycle with aquatic and terrestrial phase. Such characteristics make them good models for studying issues related to habitat change, whether concerning the identification of patterns or inferences about processes associated with fragmentation and habitat loss or occupancy and colonization in disturbed areas. Within this context, this work main goal sought to determine the diversity and structure of his assemblage of amphibians in forest remnants semideciduous (FES) and compare it with that recorded in silvicultural deployments in the mid-west region of São Paulo (Chapter 3). Besides this, we sought to survey anurans in a protected area (Conservation Unit), in order to approach the species composition in this region, before the fragmentation process (Chapter 1), and we tried to elucidate the spatial distribution of the species found in this type of forest formation (FES) and its possible biogeographical relationship with assemblages present in adjacent types of vegetation (Chapter 2). From the monthly survey of the species in the field for nine months consecutively, including the season of greatest activity for the group, and using different and complementary methodologies (pitfall traps and survey at breeding sites) were determined the abundance and richness of frogs in three comparable areas of deployment forestry (eucalyptus forestry) and three remaining forest (remnants of FES), and the only major conservation unit within a radius of 150 km. For comparison of data abundance and diversity, between forestry and forest remnants, were used univariate analysis of variance (ANOVA) with each data sets, and also descriptive techniques such as non-metric multidimentional scaling (NMDS), clustering (UPGMA) and similarity analysis... (Complete abstract click electronic access below)
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Mello, Tatiana Figueira de. "Estrutura da vegetação, cobertura florestal e preferências de uso da paisagem associadas a vertentes: as quase-florestas de São Luiz do Paraitinga". Universidade de São Paulo, 2010. http://www.teses.usp.br/teses/disponiveis/41/41134/tde-19042010-105930/.

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O município de São Luiz do Paraitinga, SP, originalmente coberto pela Floresta Atlântica estabelecida sobre os mares de morros do Planalto Atlântico, testemunhou o uso intensivo da terra que resultou em uma paisagem onde predominam pequenos fragmentos de floresta secundária. Considerando práticas agrícolas orientadas pela topografia nesta paisagem, avaliei o efeito da orientação e inclinação das vertentes na cobertura florestal e na estrutura da vegetação. Orientadas por aspectos produtivos, as preferências de utilização tiveram efeitos expressivos na configuração da paisagem. Enquanto as pastagens ocorreram preferencialmente nas vertentes mais produtivas (norte/leste), a cobertura florestal concentrou-se nas vertentes opostas e nas áreas mais declivosas, de mais difícil cultivo e acesso. A regeneração florestal ocorreu preferencialmente nas vertentes sul e nas maiores declividades, enquanto o desmatamento relativo foi maior nas vertentes norte/leste. Podemos apontar na configuração da paisagem uma origem híbrida, determinada pelas preferências (atributos culturais) e topografia (atributo natural), associados, que não poderia ser explicada por domínios separados de natureza e cultura. A estrutura da vegetação dos fragmentos desta paisagem está correlacionada apenas parcialmente com intervenções humanas que dependem da topografia, podendo sofrer influência, também, de intervenções associadas a outros elementos da paisagem, como a propriedade rural. As ações humanas, suas origens variadas e seus efeitos sobre a vegetação podem ser mais bem compreendidos de forma contextualizada, associados aos processos sociais em curso na paisagem. Ao incluirmos a ação humana nos modelos de paisagem, podemos compreender melhor os processos envolvidos na produção (e degradação) destas paisagens e ficar mais aptos a elaborar propostas de conservação adequadas às paisagens fragmentadas
This study was carried out in São Luiz do Paraitinga a county located in a hilly area in Southeastern Brazil that was originally covered by Atlantic Rainforest. The region has a history of intensive land use which resulted in a severely fragmented landscape. Under the hypothesis that agricultural practices and topography are closely linked in this landscape, I evaluated the effect of slopes orientation and inclination in forest cover and vegetation structure. Land use preferences had significant effects in shaping the landscape. While land use occurred mainly in most productive slopes (north/east), forest covered preferentially south and west facing slopes and steeper slopes. Forest regeneration occurred mainly on south facing slopes and steeper slopes, while deforestation was higher on north/east facing slopes. We propose that the landscape configuration has a hybrid origin, a product of the interplay between human choices (cultural attributes) and topography (a natural attribute), and which could not be explained by separate domains of nature and culture. Vegetation structure was only partly correlated with human interventions that are related to topography, and could also be influenced by actions related to other landscape elements, such as rural properties. Human actions, their varied origins and their effects on vegetation can be better understood if linked to social processes. Hence, if we want to improve our understanding on landscapes production and degradation, as well as propose conservation strategies appropriate to fragmented landscapes we need to explicitly include human activity in our landscape models.

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Oliveira, Patricia do Prado. "Métricas da paisagem e perspectivas de conservação para parques em situação de isolamento na cidade de São Paulo: o Parque Estadual Fontes do Ipiranga (PEFI), o Parque Estadual do Jaraguá (PEJ) e o Parque Natural Municipal Fazenda do Carmo (PNMFC), Município de São Paulo (SP)". Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/8/8135/tde-10052018-121509/.

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O município de São Paulo, a partir da década de 1970, apresentou uma rápida expansão de sua área periférica que resultou na perda de sua cobertura vegetal original. A cobertura vegetal foi reduzida a fragmentos isolados pelo rápido processo de expansão da urbanização. Esses remanescentes contam com a presença de vegetação natural secundária da Mata Atlântica, que antes ocupava boa parte do território paulista e que deu lugar à metrópole de hoje. Na tentativa de proteger esses remanescentes foram criadas unidades de conservação da natureza na paisagem urbana, como os Parques. Os parques estaduais Fontes do Ipiranga (PEFI) do Jaraguá (PEJ) e o Parque Natural Municipal Fazenda do Carmo (PNMFC) se encontram em uma situação semelhante no município de São Paulo: são unidades de proteção integral que guardam remanescentes florestais em áreas relativamente reduzidas e estão isolados em regiões densamente urbanizadas. Neste sentido trabalhou-se com a hipótese de que a condição de isolamento submeteu esses ambientes a situações que ameaçam sua conservação em longo prazo. Dentro dessa perspectiva, este estudo discute como a estrutura da paisagem pode influenciar na conservação dos remanescentes florestais protegidos por Parques que se encontram em situação de isolamento. Os Parques que devem garantir o mínimo de interferência de atividades humanas enfrentam grandes dificuldades em cumprir de forma efetiva sua função de unidade de proteção integral em ambientes urbanizados, existindo, uma relação conflituosa entre urbanização e conservação. A bacia hidrográfica foi definida como unidade de análise para este estudo, por se tratar de uma região natural e abranger também o entorno dos Parques: a bacia do córrego Ipiranga, que é um afluente do rio Tamanduateí, foi selecionada por apresentar em seu perímetro o Parque Estadual Fontes do Ipiranga (PEFI). As bacias hidrográficas dos ribeirões Vermelho e São Miguel e do córrego Santa Fé abrangem a área do Parque Estadual do Jaraguá (PEJ); e, a bacia hidrográfica do rio Aricanduva, conta com a presença do Parque Natural Municipal Fazenda do Carmo (PNMFC). Foram elaborados mapas de uso e cobertura da terra para a reconstituição da paisagem das bacias hidrográficas e para identificação das mudanças provocadas principalmente pelo processo de urbanização. Foram utilizadas fotografias áreas dos anos de 1962 e 1994, e, Imagens do satélite RapidEye para realização do mapeamento; e, posteriormente foram geradas métricas da paisagem para análise da situação atual e pretérita dos remanescentes florestais presentes nas bacias hidrográficas. Partiu-se dos pressupostos teóricos da Ecologia da Paisagem, observado como as mudanças do uso e cobertura da terra e o processo de urbanização interferiram na dinâmica e nas condições ecológicas desses remanescentes florestais protegidos por Parques no município de São Paulo. Com a análise dos dados obtidos a partir das métricas da paisagem foi possível estabelecer as principais tendências e prognósticos para a conservação desses fragmentos e discutir sobre ações possíveis para amenizar o isolamento e melhorar as condições ecológicas desses remanescentes.
The municipality of São Paulo, from the 1970s, presented a rapid expansion of its peripheral area that resulted in the loss of its original vegetation cover. The vegetation cover was reduced to fragments isolated by the process of urbanization expansion. These remnants have a presence of secondary natural vegetation of the Atlantic Rain Forest, which used to occupy a good part of the territory of São Paulo and that gave rise to today\'s metropolis. In an attempt to protect these remnants, nature conservation units were created in the urban landscape, such as the Parks. The Parque Estadual Fontes do Ipiranga (PEFI), Parque Estadual do Jaraguá (PEJ) and and the Parque Natural Municipal Fazenda do Carmo (PNMFC) are located in a non-municipal situation of São Paulo: they are integral protection units that keep remnants of forest in relatively small areas and are isolated in densely urbanized regions. In this sense we worked with a hypothesis of an isolation condition subjected these environments to situations that threaten their conservation in long term. From this perspective, this study discusses how a landscape structure can influence the conservation of forest remnants protected by Parks that are in isolation. The parks that must guarantee the minimum interference of human activities face great difficulties in effectively fulfilling their function as integral protection unit in urbanized environments, existing a conflicting relationship between urbanization and conservation. The hydrographic basin was defined as a unit of analysis for this study, because it is a natural region and also encompasses the surroundings of the Parks: a basin of the Ipiranga stream, which is a tributary of the Tamanduateí river, was selected for presenting in its perimeter Parque Estadual Fontes do Ipiranga (PEFI). As watersheds of the Vermelho and São Miguel streams and the Santa Fe stream cover an area of the Parque Estadual do Jaraguá (PEJ); And, a watershed of the Aricanduva river, counts on presence in the Parque Natural Municipal Fazenda do Carmo (PNMFC). Land use and land cover maps were prepared for a reconstruction of the river basin landscape and for the identification of the changes brought about by the urbanization process. Photographs were made of areas from the years 1962 and 1994, and, Images of the RapidEye satellite to perform the mapping; And, later, metrics of the landscape were generated to analyze the present and preterite situation of the forest remnants present in the hydrographic basins. It was based on the theoretical assumptions of Landscape Ecology, observed how changes in land use and coverage and the urbanization process interfered in the dynamics and ecological conditions of forest remnants protected by Parks in the city of São Paulo. With an analysis of the data obtained from the landscape metrics, it is possible to establish as main tendencies and prognoses for the conservation of the losses and to discuss possible actions to soften the isolation and to improve the ecological conditions of the remnants.

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Infante, In?s de Souza. "Avalia??o do potencial dos munic?pios do estado do Rio de Janeiro no repasse do ICMS Verde a partir da cria??o de unidades de conserva??o". Universidade Federal Rural do Rio de Janeiro, 2010. https://tede.ufrrj.br/jspui/handle/jspui/1620.

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CAPES
The creation of conservation units is to preserve and / or conserving biodiversity. However, the space reserved for them limits, sometimes, the development and economic growth, which can generate conflicts. To minimize this problem, in 1991, was created in the Paran? Ecological VAT, whose initial goal was to compensate municipalities that had entered its territory in protected areas. Thirteen federal states followed Parana?s example and, with some variations to the adopted criteria for the transfer, also developed and implemented that instrument. Among them is the Rio de Janeiro state, which by Law 5.100 of October 4, 2007, created the Green ICMS. The criteria adopted by Rio de Janeiro take into account the existence of conservation, water quality and management of solid waste in each municipality. The aim of this study is evaluating the potential of Rio de Janeiro?s municipalities to participate in the transfer of Green ICMS from the creation of new conservation areas potential. The methodology adopted in this work simulates the creation of parks and APAs in three different scenarios, using 100%, 75% or 50% of the forest remnants in each of the 92 municipalities of Rio de Janeiro? states. The indexes of municipal protected area and the relative indexes of municipal protected area needed to determine the amount to be transferred to each municipality followed the guidelines in the present Decree 41.844 of May 4, 2009. In 92 municipalities of Rio de Janeiro?s state, 28 have protected areas under their tutelage, and they occupy 98.449ha, equivalent to 8.43% of the remaining forests of the state, and town of Parati is one that contains higher remaining area. In 67 municipalities there are remnants that can be converted into protected areas. The biggest benefit from the creation of parks in 100% of its remnants would be Rio Claro, in 75% and 50% would Angra dos Reis. In the case of establishing APAs using 100%, 75% or 50% of their remaining forest the city to receive greater value would pass Angra dos Reis.
A cria??o de unidades de conserva??o visa ? preserva??o e/ou conserva??o da biodiversidade. Entretanto, o espa?o a elas reservado limita, por vezes, o desenvolvimento e o crescimento econ?mico, podendo gerar conflitos. Para minimizar esse problema, em 1991, foi criado no Paran? o ICMS Ecol?gico, cujo objetivo inicial foi compensar os munic?pios que tivessem inseridas em seu territ?rio unidades de conserva??o. Mais treze estados da federa??o seguiram exemplo do Paran? e, com algumas varia??es em rela??o aos crit?rios adotados para o repasse, tamb?m criaram e implementaram esse instrumento. Entre eles, est? o estado do Rio de Janeiro, que atrav?s da lei n? 5.100, de 4 de outubro de 2007, criou o ICMS Verde. Os crit?rios adotados por esse estado levam em conta a exist?ncia de unidades de conserva??o, a qualidade da ?gua e a administra??o dos res?duos s?lidos em cada munic?pio. Este trabalho tem como objetivo avaliar o potencial dos munic?pios do estado do Rio de Janeiro de participa??o no repasse do ICMS Verde a partir da cria??o de novas unidades de conserva??o. A metodologia adotada para a realiza??o deste trabalho consiste em simular a cria??o de Parques e APAs em tr?s cen?rios distintos, utilizando 100%, 75% ou 50% dos remanescentes florestais de cada um dos 92 munic?pios do estado do Rio de Janeiro. Os ?ndices de ?rea protegida municipal e os ?ndices relativos de ?rea protegida municipal necess?rios para determinar o valor a ser repassado a cada munic?pio seguiram as orienta??es presentes no Decreto 41.844, de 04 de maio de 2009. Dos 92 munic?pios do estado do Rio de Janeiro, 28 possuem unidades de conserva??o sob sua tutela, sendo que as mesmas ocupam uma ?rea de 98.449ha, equivalente a 8,43% dos remanescentes florestais do estado, sendo o munic?pio de Parati aquele que cont?m maior ?rea de remanescentes. Em 67 munic?pios ainda h? remanescentes florestais pass?veis de serem convertidos em unidades de conserva??o. O maior beneficiado com a cria??o de Parques em 100% de seus remanescentes seria o munic?pio de Rio Claro, em 75% e 50% seria Angra dos Reis. No caso da cria??o de APAs utilizando 100%, 75% ou 50% de seus remanescentes florestais, o munic?pio a receber maior valor de repasse seria Angra dos Reis.

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Gross, Aline. "Dinâmica da Floresta Ombrófila Mista no Planalto Sul Catarinense". Universidade do Estado de Santa Catarina, 2017. http://tede.udesc.br/handle/handle/2348.

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FUMDES
The present dissertationaimed to investigate the tree component dynamics in different forest remnants in “Planalto Sul Catarinense Region”. In particular, I seek to understand how edaphoclimatic variables, anthropogenic chronic disturbances, landscape and forest structure could influence the regional scale spatial variation of tree species demographics rates. This information is essential for a better comprehension of forest ecosystems functioning ina contemporary context, marked by frequent chronical anthropogenic disturbances. Thus, I obtained data from permanent plots tree component monitoring and environmental conditions (edaphoclimatic, altitude, landscape and cattle presence) of nine forest remnants in the municipalities of Capão Alto, São José do Cerrito, Lages, Painel, Urubici and Bom Jardim da Serra, in Santa Catarina State. Principal Components Analysis (PCAs) were performed in order to identify regional scale tree component dynamics pattern and ecological gradients. The influence of explicative variables on dynamics patterns was verified by Regression Tree. In the first and second inventory a mean tree density of 1,583 e 1,546 ind.ha-1 were observed, representing a mean net change rate of -0.61%.year-1. For basal area, values of 34.74 m2.ha-1and 35.79 m2.ha-1were observed, represent a mean net change rate of 0.79%.year-1.In regional scale, the Araucaria Forest dynamics varied, mostly, in mortality and basal area loss rates. In general, mortality and basal area loss rates were smaller in well-structured (greater values of basal area) larger fragments with smaller proportion of edge areas. Therefore, I conclude that, in regional scale, anthropogenic fragmentation impacted significantly the tree component dynamics in the study Araucaria Forest areas
A presente dissertação teve como objetivo geral investigar a dinâmica do componente arbóreo em diferentes remanescentes florestais na região do Planalto Sul Catarinense. Em particular, buscou-se compreender a influência de variáveis edafoclimáticas, de perturbações antropogênicas crônicas, da paisagem e estruturação da floresta sobre a variação espacial das taxas demográficas de espécies arbóreas em escala regional. Informações desta natureza são fundamentais para a compreensão do funcionamento dos ecossistemas florestais no contexto da época em que vivemos, caracterizada pela presença marcante de impactos crônicos causados por atividades de origem antrópica. Desta forma, foram obtidos dados de monitoramento de parcelas permanentes do componente arbóreo e de condições ambientais (altitude, variáveis edafoclimáticas, da paisagem e presença de gado) de nove remanescentes de Floresta Ombrófila Mista, situados nos municípios de Capão Alto, São José do Cerrito, Lages, Painel, Urubici e Bom Jardim da Serra, no Estado de Santa Catarina. Visando identificar os padrões de dinâmica do componente arbóreo e gradientes ecológicos em escala regional, foi utilizado uma abordagem multivariada através da Análise de Componentes Principais (PCA). A influência das variáveis explicativas sobre o padrão de dinâmica foi avaliada por meio de Árvore de Regressão. Entre o primeiro e o segundo inventário foram observados, respectivamente, uma densidade média de 1.583 e 1.546 ind.ha-1, o que representou uma taxa de mudança líquida média de -0,61%.ano-1. Para área basal, os valores foram de 34,74 m2.ha-1 e 35,79 m2.ha-1, com mudança líquida de 0,79%ano-1. Em escala regional, a dinâmica das áreas de Floresta com Araucária variou, principalmente, no que se refere as taxas de mortalidade e perda em área basal. De forma geral, fragmentos maiores, com menor proporção de bordas e mais bem estruturados (maior área basal) apresentaram menores taxas de mortalidade e perda em área basal. Assim, conclui-se que, em escala regional, a fragmentação antrópica impactou de forma significativa os padrões de dinâmica observados nas áreas de Floresta Ombrófila Mista

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Brassaloti, Ricardo Augusto [UNESP]. "Diversidade e estrutura de taxocenoses de anfíbios anuros em uma paisagem fragmentada no centro-oeste paulista". Universidade Estadual Paulista (UNESP), 2010. http://hdl.handle.net/11449/87615.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Anfíbios anuros são particularmente sensíveis a alterações no habitat, seja pela sua baixa vagilidade e fidelidade a áreas de reprodução e forrageio, ou mesmo, por possuírem ciclo de vida complexo com fase aquática e terrestre. Tais características os tornam bons modelos para o estudo de questões relacionadas à modificação no habitat, sejam elas relativas a identificação de padrões ou inferência sobre processos associados à fragmentação ou perda de habitat original ou mesmo ocupação e colonização em áreas alteradas. Dentro deste contexto, este trabalho procurou como objetivo principal, determinar a diversidade e estrutura da taxocenose de anfíbios anuros presente em remanescentes de floresta estacional semidecidual (FES) e compará-la com a registrada em implantações silviculturais, na região centro-oeste do estado de São Paulo (capítulo 3). Além deste, buscou-se o levantamento da fauna em uma área preservada (Unidade de Conservação), afim de aproximar-se da composição presente na região antes do processo de fragmentação (capítulo 1), além da distribuição espacial das espécies encontradas nesse tipo de formação florestal (FES) e sua possível relação biogeográfica com taxocenoses presentes nas fitofisionomias limítrofes a ela (capítulo 2). A partir do levantamento mensal das espécies em campo durante nove meses consecutivos, compreendidos na estação de maior atividade para o grupo, e utilizando-se de metodologias diferentes e complementares (armadilhas de interceptação e queda e procura em ambientes de reprodução), foram determinadas a abundância e a riqueza de anuros em três áreas comparáveis de implantação florestal (silvicultura de eucalipto) e três remanescentes florestais (fragmentos de FES), além da única grande unidade de conservação em um raio de 150 km...
Frogs are particularly sensitive to changes in habitat, either by their low vagility and fidelity to breeding and foraging sites, or even by had a complex life cycle with aquatic and terrestrial phase. Such characteristics make them good models for studying issues related to habitat change, whether concerning the identification of patterns or inferences about processes associated with fragmentation and habitat loss or occupancy and colonization in disturbed areas. Within this context, this work main goal sought to determine the diversity and structure of his assemblage of amphibians in forest remnants semideciduous (FES) and compare it with that recorded in silvicultural deployments in the mid-west region of São Paulo (Chapter 3). Besides this, we sought to survey anurans in a protected area (Conservation Unit), in order to approach the species composition in this region, before the fragmentation process (Chapter 1), and we tried to elucidate the spatial distribution of the species found in this type of forest formation (FES) and its possible biogeographical relationship with assemblages present in adjacent types of vegetation (Chapter 2). From the monthly survey of the species in the field for nine months consecutively, including the season of greatest activity for the group, and using different and complementary methodologies (pitfall traps and survey at breeding sites) were determined the abundance and richness of frogs in three comparable areas of deployment forestry (eucalyptus forestry) and three remaining forest (remnants of FES), and the only major conservation unit within a radius of 150 km. For comparison of data abundance and diversity, between forestry and forest remnants, were used univariate analysis of variance (ANOVA) with each data sets, and also descriptive techniques such as non-metric multidimentional scaling (NMDS), clustering (UPGMA) and similarity analysis... (Complete abstract click electronic access below)

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Gerotti, Raphael Whitacker [UNESP]. "Análise das variáveis tempo e distância no método “pontos de contagem” no estudo da assembleia de aves na estação ecológica de Caetetus (EECa), São Paulo". Universidade Estadual Paulista (UNESP), 2017. http://hdl.handle.net/11449/151361.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Pontos de contagem é um método atrativo para utilização em programas de monitoramento de aves por ser simples e permitir que vários locais sejam amostrados. Contudo, nos estudos realizados em regiões tropicais utilizando-se deste método, os autores utilizam a variável "tempo" de forma diferente para registrar a abundância das aves nos fragmentos florestais. Portanto, os dados obtidos por estes diferentes estudos não podem ser comparados entre si, pois o tempo gasto nos pontos e o tempo total das contagens diferem significativamente, assim como as distâncias percorridas. Desta forma, o objetivo do presente trabalho foi o de comparar quatro durações de tempos distintas (5, 10, 15 e 20 minutos) para identificar qual destas registra maior riqueza e abundância de aves em fragmentos de florestas tropicais. As amostragens foram realizadas durante 12 meses em um fragmento de floresta estacional semidecidual de 2.180 ha no interior de São Paulo. Um total de 120 minutos de amostragem foi realizado a cada mês para cada tempo distinto, o que exigiu um número diferente de pontos amostrais e uma diferente distância total percorrida na floresta. Com relação à riqueza e abundância, os testes estatísticos evidenciaram que o tempo de cinco minutos apresentou resultados que diferem significativamente dos outros tempos (10’, 15’ e 20’). Além disso, houve uma correlação positiva entre as diferentes distâncias percorridas e a abundância registrada, ou seja, quanto maior a distância percorrida, maior a riqueza e abundância registradas. Um aspecto da ecologia da comunidade que deve ser levado em consideração é que as espécies são distribuídas de forma heterogênea em uma floresta, pois diferentes espécies de plantas e diferentes padrões na fisionomia da floresta proporcionam diferentes tipos de micro-hábitats para aves. Quando se utiliza um maior número de pontos de amostragem, espera-se encontrar uma maior heterogeneidade da floresta, portanto, a maior riqueza registrada pela contagem de cinco minutos está associada a um maior número de pontos necessários para isolar a variável tempo. Outro fator importante é a variação encontrada nos valores do Índice Pontual de Abundância amostrados. A menor variação e consequente maior poder estatístico ocorreu na contagem mais curta (5’ minutos), indicando que o tempo é o mais eficiente para atingir os objetivos propostos. É importante ressaltar que este período de tempo exigiu quatro meses a menos para registrar o mesmo número de espécies que as outras contagens. No oitavo mês de amostragem, o tempo de cinco minutos já acumulava 119 espécies, valor maior que a riqueza total obtida com os outros tempos. Portanto, ao utilizar o método de pontos de contagem para analisar a estrutura da comunidade de aves em fragmentos florestais, o melhor resultado foi alcançado com a contagem de cinco minutos. Este tempo provou ser mais eficiente por detectar maior riqueza e abundância com menor esforço amostral, além de aumentar a chance de se registrar novas espécies devido ao maior número de pontos realizados em um maior número de micro-hábitats na floresta.
Point counts are attractive for use in avian monitoring programs because they are straightforward and allow numerous geographic sites to be sampled. However, in studies conducted with the point count method in tropical regions, authors use the variable "time" differently to record the abundance of birds in forest remnants. Therefore, the data obtained by different studies cannot be compared since the time spent at the points and the total counting time differ significantly, as do the distances traveled. The objective of the present study was to compare four distinct point count times (5, 10, 15 and 20 minutes) to identify which registers relatively greater bird richness and abundance in tropical forest fragments. Samplings were carried out for 12 months in a 2,180 ha fragment of semideciduous forest in the interior of the state of São Paulo. A total of 120 minutes of sampling was carried out each month for each counting time, which required a different number of counting points and a different total distance traveled in the forest. With respect to richness and abundance, the statistical tests showed that five minutes of counting yielded results that were significantly different from those of the other point count times. Additionally, there was a positive correlation between the different distances traveled and the recorded abundance, i.e., the greater the distance traveled, the greater the richness and abundance. One aspect of community ecology that must be considered is that species are distributed heterogeneously in a continuous forest because different plant species and different patterns in the terrain of the forest provide different microhabitats for birds. When a greater number of sampling points is used, greater forest heterogeneity is expected; therefore, the greater richness recorded by the five-minute counts is associated with a greater number of points needed to isolate the time variable. Another important factor is the variation in the sampling rates; the lowest variation, and consequently greater statistical power, occurred in the shortest count (5′), indicating that this counting time is effective for meeting the proposed objectives. Importantly, this counting time required four fewer months to record the same number of species as the other times. By the eighth month of sampling, the five-minute count had accumulated 119 species, which was higher than the total richness obtained with the other times. Therefore, when using the point method to analyze the community structure of birds in forest fragments, the best result was achieved with the five-minute count. This time proved to be more efficient because it detected greater richness and abundance with a lower sampling effort and increased the chance of registering new species due to the higher number of sampling points over a larger number of microhabitats in the forest.

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Gerotti, Raphael Whitacker. "Análise das variáveis tempo e distância no método “pontos de contagem” no estudo da assembleia de aves na estação ecológica de Caetetus (EECa), São Paulo". Botucatu, 2017. http://hdl.handle.net/11449/151361.

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Orientador: Reginaldo José Donatelli
Resumo: Pontos de contagem é um método atrativo para utilização em programas de monitoramento de aves por ser simples e permitir que vários locais sejam amostrados. Contudo, nos estudos realizados em regiões tropicais utilizando-se deste método, os autores utilizam a variável "tempo" de forma diferente para registrar a abundância das aves nos fragmentos florestais. Portanto, os dados obtidos por estes diferentes estudos não podem ser comparados entre si, pois o tempo gasto nos pontos e o tempo total das contagens diferem significativamente, assim como as distâncias percorridas. Desta forma, o objetivo do presente trabalho foi o de comparar quatro durações de tempos distintas (5, 10, 15 e 20 minutos) para identificar qual destas registra maior riqueza e abundância de aves em fragmentos de florestas tropicais. As amostragens foram realizadas durante 12 meses em um fragmento de floresta estacional semidecidual de 2.180 ha no interior de São Paulo. Um total de 120 minutos de amostragem foi realizado a cada mês para cada tempo distinto, o que exigiu um número diferente de pontos amostrais e uma diferente distância total percorrida na floresta. Com relação à riqueza e abundância, os testes estatísticos evidenciaram que o tempo de cinco minutos apresentou resultados que diferem significativamente dos outros tempos (10’, 15’ e 20’). Além disso, houve uma correlação positiva entre as diferentes distâncias percorridas e a abundância registrada, ou seja, quanto maior a distância percorrida, mai... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: Point counts are attractive for use in avian monitoring programs because they are straightforward and allow numerous geographic sites to be sampled. However, in studies conducted with the point count method in tropical regions, authors use the variable "time" differently to record the abundance of birds in forest remnants. Therefore, the data obtained by different studies cannot be compared since the time spent at the points and the total counting time differ significantly, as do the distances traveled. The objective of the present study was to compare four distinct point count times (5, 10, 15 and 20 minutes) to identify which registers relatively greater bird richness and abundance in tropical forest fragments. Samplings were carried out for 12 months in a 2,180 ha fragment of semideciduous forest in the interior of the state of São Paulo. A total of 120 minutes of sampling was carried out each month for each counting time, which required a different number of counting points and a different total distance traveled in the forest. With respect to richness and abundance, the statistical tests showed that five minutes of counting yielded results that were significantly different from those of the other point count times. Additionally, there was a positive correlation between the different distances traveled and the recorded abundance, i.e., the greater the distance traveled, the greater the richness and abundance. One aspect of community ecology that must be considered is that... (Complete abstract click electronic access below)
Mestre

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Marchesan, Juliana. "Análise espacial da fragmentação florestal em áreas do bioma mata atlântica utilizando linguagem R". Universidade Federal de Santa Maria, 2017. http://repositorio.ufsm.br/handle/1/12858.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES
There are decades the deforestation resulting from the process of anthropization of the landscape has been causing the destruction of natural resources. The native forests are giving space mainly for agriculture, cattle raising and urbanization, occurring the formation of fragments. In this context, the present study aims to develop an R language package for the calculation of landscape ecology metrics, as well as, to use the same for the analysis of the forest fragments, under the domain of the Atlantic Forest biome, located in the hydrographic sub-basin of Arroio Jaquirana, Rio Grande do Sul, for the year 2016. For the development of the package, called LanscapeMetrics, used the R software and packages igraph, raster, rgdal, rgeos, devtools, roxygen2 and Rtools. In order to avoid the use of redundant metrics a total of twenty-one was selected covering metrics of area and density, shape, border, central area and proximity. For the mapping of the forest fragments, used images of the RapidEye/REIS satellite dated 02/29/2016, with the definition of two classes of land use and cover: native forest and other uses. The classification was supervised through the Bhattacharyya algorithm, using SPRING software. The fragments were analyzed separately in size classes, to separate them used the software R. The results showed that the native forest occupied 14,099.89 ha, corresponding to 34.01% of the study area, covering a total of 1,995 fragments, of which 93.43% less than 5 ha. In the size class occupied by the fragments smaller than 5 ha, it was found a higher edge value and a perimeter-area ratio, indicating a greater edge effect, so that the central areas of these remnants are exposed to the effects of the external matrix. This fact is proved by the calculation of the metrics of central areas, since, subject to the edge distances from 80 m, total domination by the edge effect occurs. However, these smaller fragments are important, since they lessen the distance between the larger fragments, due to their high density and being well distributed in the study area. Thus, it is concluded that R is a promising and efficient tool for spatial data analysis, which allowed the manipulation of data from remote sensors.
Há décadas os desmatamentos decorrentes do processo de antropização da paisagem vêm ocasionando a destruição dos recursos naturais. As florestas nativas foram cedendo espaço principalmente para agricultura, pecuária e urbanização, ocorrendo a formação de fragmentos. Desse modo, o presente estudo tem por objetivo desenvolver um pacote em linguagem R para cálculo de métricas de ecologia da paisagem, bem como, utilizar o mesmo para análise dos fragmentos florestais, sob domínio do bioma Mata Atlântica, localizados na sub-bacia hidrográfica do Arroio Jaquirana, Rio Grande do Sul, para o ano de 2016. Para o desenvolvimento do pacote, denominado LanscapeMetrics, utilizou-se o programa R e os pacotes igraph, raster, rgdal, rgeos, devtools, roxygen2 e Rtools. De modo a evitar a utilização de métricas redundantes foram selecionadas um total de vinte e uma, abrangendo métricas de área e densidade, forma, borda, área central e de proximidade. Para o mapeamento dos fragmentos florestais utilizou-se imagens do satélite RapidEye/REIS datadas de 29/02/2016, com a definição de duas classes de uso e cobertura da terra: floresta nativa e outros usos. A classificação foi de forma supervisionada por meio do algoritmo Bhattacharyya, utilizando o programa SPRING. Os fragmentos foram analisados separadamente em classes de tamanho, para separá-los utilizou-se o programa R. Os resultados demonstraram que a floresta nativa ocupou 14.099,89 ha, correspondendo a 34,01% da área de estudo, abrangendo um total de 1.995 fragmentos, destes, 93,43% inferiores à 5 ha. Na classe de tamanho ocupada pelos fragmentos menores que 5 ha, encontrou-se maior valor de borda e de razão perímetro-área, indicando maior efeito de borda, dessa forma, as áreas centrais destes remanescentes estão expostas aos efeitos da matriz externa. Este fato é comprovado pelo cálculo das métricas de áreas centrais, uma vez que, submetidos às distâncias de borda a partir de 80 m, ocorre total dominação pelo efeito de borda. Contudo, estes fragmentos menores são importantes, uma vez que amenizam a distância entre os fragmentos maiores, devido sua alta densidade e por estarem bem distribuídos na área de estudo. Desse modo, conclui-se que o R é uma ferramenta promissora e eficiente para análise de dados espaciais, o qual permitiu a manipulação de dados provenientes de sensores remotos.

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Goins, Sean Michael. "Dynamics and Disturbance in an Old-Growth Forest Remnant in Western Ohio". University of Dayton / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=dayton1341941451.

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Keeton, William Scott. "Occurrence and reproductive role of remnant old-growth trees in mature Douglas-fir forests, southern Washington, Cascade Range /". Thesis, Connect to this title online; UW restricted, 2000. http://hdl.handle.net/1773/5479.

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Alexandrino, Eduardo Roberto. "A paisagem antrópica sob avaliação: a avifauna em remanescentes florestais, matrizes agrícolas e as implicações para a conservação". Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/91/91131/tde-19102015-174122/.

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Devido o dinamismo e complexidade estrutural observada nas paisagens antrópicas, pesquisas contínuas são necessárias para melhorar o conhecimento sobre quais os impactos delas na biodiversidade, bem como para entender quais espécies ocorrentes nestas paisagens refletem as condições ambientais lá existentes. Desse modo, tomando a avifauna como representante da biodiversidade presente nestas paisagens, esta tese objetivou: 1) caracterizar as assembleias de aves ocorrentes nos remanescentes florestais de Mata Atlântica inseridos em paisagem antrópica agrícola, bem como as assembleias que ocorrem no interior das culturas de pasto e cana-de-açúcar, 2) identificar um método analítico adequado para acessar a integridade ecológica existente nos remanescentes florestais por meio das assembleias de aves, 3) avaliar o efeito da estrutura e dinâmica destas paisagens nas assembleias de aves ocorrentes nos remanescentes florestais, 4) identificar quais características da paisagem antrópica agrícola influenciam as aves ocorrentes no interior das culturas de pasto e cana-de-açúcar. Assembleias de aves foram amostradas mensalmente durante um ano (Nov2011-Nov2012) por meio de pontos fixos e transectos em oito remanescentes florestais com diferentes tamanhos (3-115ha) e históricos de degradação, e oito sítios amostrais localizados no interior das culturas agrícolas (quatro em pasto e quatro em cana-de-açúcar). Estes foram selecionados dentro de cinco unidades amostrais de uma paisagem tipicamente (16 km2) agrícola do Estado de São Paulo (Bacia do Rio Corumbataí). O índice de serviços ecossistêmicos de Ferraz et al. (2014) foi adotado como uma medida do grau de distúrbios antrópicos presente nos remanescentes florestais do qual leva em consideração a dinâmica e estrutura deles. Já as características das paisagens nas culturas agrícolas foram coletadas em duas escalas de análise (buffers circulares de 600 e 1000m) levando em consideração métricas que pudessem refletir uma maior heterogeneidade da paisagem. No total, 191 espécies foram observadas nos remanescentes florestais, enquanto que 137 nas culturas agrícolas. As aves com hábitos florestais, não-florestais, hábitos mistos florestais-não-florestais, pequenos insetívoros de sub-bosque, aves que forrageiam no estrato médio dos remanescentes, espécies endêmicas e ameaçadas foram os melhores indicadores ecológicos nos remanescentes. Estes grupos formaram a base de dados do Índice de Integridade Biótica (IIB) um método multimétrico que obteve um melhor desempenho em refletir a integridade existente nos remanescentes quando comparado com os níveis de sensibilidade a distúrbios antrópicos de Parker III et al. (1996), riqueza geral das assembleias e índice de diversidade de Shannon. Foram registradas 132 espécies nas pastagens enquanto que apenas 72 nos canaviais, sendo que tanto a riqueza geral quanto a abundância relativa de alguns grupos de aves foram explicadas pela variação na heterogeneidade da paisagem. Assim, conclui-se que métodos analíticos classicamente utilizados em ecologia podem apresentar falhas na avaliação ecológica de remanescentes de Mata Atlântica inseridos em paisagem antrópica, ocasionando interpretações errôneas. Novos métodos analíticos devem ser explorados, sendo o IIB um possível substituto. A diferença existente entre as assembleias de aves ocorrentes nas pastagens, (maior heterogeneidade) e nos canaviais (baixa heterogeneidade) indicam as consequências negativas que homogeneização da paisagem agrícola pode ocasionar à biodiversidade ocorrente nestas paisagens.
Because human-modified landscapes (HML) are dynamic and have structural complexity, continuous research is necessary to improve knowledge about the HML impacts on the biodiversity, as well as to provide knowledge of which current species may reflect the environmental conditions existing there. Thus, considering birds as sample of the HML existing biodiversity, the following thesis aimed to: 1) describe the bird assemblages of Atlantic Forest patches located in HML and bird assemblages of the interior of cattle pastures and sugar cane crops, 2) identify a proper bird analytical approach to assess the existing ecological integrity of forest patches in HML, 3) assess the effects of the landscape features (dynamic and structure) on the bird assemblages of forest patches in HML, 4) identify which landscapes features of both crops may exert influence on the bird assemblage composition of each crop. Bird sampling was performed monthly along one year (Nov 2011 - Nov 2012) in eight forest patches with different historical and size (3 - 115 ha), and eight sites located in the interior of each crop (four in cattle pasture and four in sugar cane), using point counts and transects. Five focal landscapes (16 km2) located in a typical HML of São Paulo state (Corumbataí river basin) were used to select these sampling sites. The rank of ecosystem services provisioning of Ferraz et al. (2014) was used as a measurement of the existing gradient of human disturbance in the forest patches, which was built through information about forest dynamic and structure. The landscape features of each crop were collected through two scale of analysis (circular buffers with 600 and 1000 radius meters) taking into account metrics that may represent the landscape heterogeneity. 191 species were observed in the forest patches while 137 in the crops. The forest birds, non-forest birds, birds with forest-non-forest habits, small understory-midstory insectivorous, species with foraging habits in the midstory strata, threatened and endemic species, were the best ecological indicators of the forest patches. These bird groups were used as database in the development of the Index of Biotic Integrity (IBI), a multimetric approach, which showed a better performance to indicate the existent integrity in the forest patches in comparison with \"sensitivity to disturbance\" of Parker III et al. (1996), total species richness and Shannon´s diversity index. 132 species were observed in cattle pastures while 72 in sugar cane. Both richness and relative abundance of some bird groups were explained by the landscape heterogeneity variation. Thus, it is possible to conclude that some classical birds analytical approaches may be flawed in the ecological assessment of Atlantic Forest patches inserted in HML. New analytical approaches should be explored, and the IBI is a possible alternative. The bird\'s assemblage differences between cattle pastures (high heterogeneity) and sugar cane (low heterogeneity) are an example of the negative consequences caused by the crops homogenization on the living biodiversity of agricultural landscapes.

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Berry, Christopher J. J. "Post-dispersal seed predation in a conifer-broadleaf forest remnant : the importance of exotic mammals". Lincoln University, 2006. http://hdl.handle.net/10182/666.

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Despite extensive international acceptance of the critical role of mammalian post-dispersal seed predation in many plant communities, in New Zealand we have limited knowledge of these predators’ influence on plant recruitment in our forests. The principle objective of my thesis was to determine the importance of exotic mammals as post-dispersal seed predators in a New Zealand conifer-broadleaf forest remnant. To address this goal, I used a series of field-based experiments where the actions of different post-dispersal seed predators were separated by wire-mesh exclosures. My study was conducted at Mount Peel Forest Park Scenic Reserve, South Canterbury, New Zealand. Being a human modified conifer forest currently dominated by broadleaf species, it is typical of forest remnants in New Zealand. This presented an opportunity to study a wide range of both potential post-dispersal seed predators and broadleaf tree species. My findings indicate that exotic mammals are not only post-dispersal seed predators at Peel Forest, but are responsible for the majority of post-dispersal predation events observed. Ship rats (Rattus rattus) were the dominant post-dispersal seed predators, while brushtail possums (Trichosurus vulpecula), house mice (Mus musculus) and native invertebrates were also important post-dispersal seed predators for several tree species. Through use of time-lapse video and cafeteria experiments I found that exotic mammalian seed predators, when compared to native invertebrate seed predators, preyed upon larger-seeded plant species and were responsible for considerable seed losses of several tree species. However, exotic mammalian seed predators do share several foraging characteristics with native invertebrate seed predators, as predators foraged in similar habitats and responded in a similar way to changes in seed density. In investigating if post-dispersal seed predation by mammals had a flow-on effect to plant recruitment, I observed natural seedling densities at Peel Forest were significantly higher in the absence of mammalian seed predators, but I found no evidence that the presence of mammals significantly altered the overall species richness. At the community level, I did not find an interaction between habitat and exotic mammals, however I present evidence that for individual plant species a significant mammal : habitat interaction occurred. Consequently, even though my cafeteria experiment implied there was no significant difference in the overall amount of seed preyed upon within different habitats, the less favourable microsite conditions for germination under an intact continuous canopy allows mammals to exacerbate habitat-related patterns of seed mortality and have a noticeable effect on seedling establishment. In an effort to validate the use of manipulative experiments to predict the long-term effect of post-dispersal seed predation on plant dynamics, I attempted to link results of my cafeteria experiment with observed seedling abundance at Peel Forest. Seven tree species were used in this comparison and a strong correlation was observed. This result shows that the level of post-dispersal seed predation determined in the cafeteria experiment provided a good predictor of the effect of mammalian post-dispersal seed predation on seedling establishment. To fully gauge the impact of mammalian post-dispersal seed predators on seedling establishment, the relationship between these seed predators and the type of recruitment limitation experienced by a plant species was also investigated. By using a combination of seed addition, plot manipulations and seed predator exclusion I was able to investigate this relationship. I found evidence that seed limitation at Peel Forest is positively correlated with seed size, and that while mammalian post-dispersal seed predators can further reduce plant recruitment of plant species experiencing seed limitation, the influence of mammals in determining plant recruitment was limited for plant species experiencing microsite limitation. My study has proven that exotic mammals are now the dominant post-dispersal seed predators at Peel Forest, the amount of seed preyed upon varies among plant species, and post-dispersal seed predation by mammalian species can lead to differences in seedling richness and abundance. I proved that the influence of exotic mammals on seedling establishment is also linked to habitat structure and recruitment limitations. When combined these observations suggest that exotic mammalian post-dispersal seed predators may play an important role in determining landscape abundance and distribution of plants at Peel Forest.

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Lindgren, Jessica. "Small remnant habitats : Important structures in fragmented landscapes". Doctoral thesis, Stockholms universitet, Institutionen för naturgeografi, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-148653.

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The world-wide intensification of agriculture has led to a decline in species richness due to land use change, isolation, and fragmentation of natural and semi-natural habitats in agricultural and forestry landscapes. As a consequence, there is a current landscape management focus on the importance of green infrastructure to mitigate biodiversity decline and preserve ecosystem functions e.g. pollination services and pest control. Even though intensification in agriculture has been ongoing for several hundreds of years, remnant habitats from earlier management practices may still be remaining with a surprisingly high plant richness. Preserving these habitats could help conserving plant species richness in agricultural landscapes, as well as other organisms that are dependent on plants for food and shelter. In this thesis I focus on two small remnant habitats; midfield islets and borders between managed forest and crop field in southeastern Sweden. In the past, both habitats were included in the grazing system and therefore often still have remnant population of grassland specialist species left today. I have used these two remnant habitats as model habitats to investigate the effect of landscape factors and local factors on species richness of plants, flower morphologies and plants with fleshy fruits. Additively, I analysed the effect of surrounding landscape and local openness on the functions; pollination success, biological pest control of aphids and seed predation on midfield islets. One of my studies showed that spatial distribution and size of the habitat affected plant species richness. Larger habitat size and higher connectivity between habitats increased species richness of plants in the habitats. Openness of the habitats was shown to be an important factor to increase species richness and richness of flower morphologies, both on midfield islets and in forest borders. Even though midfield islets had the highest species and morphology richness, both habitat types are needed for habitat complementary as forest borders have more plants with fleshy fruits and a higher richness of plant species that flowers in spring/early summer. It was also shown that a more complex forest border, not just with gaps in the canopy, but also with high variation in tree stem sizes increases plant species richness in the field layer. The conclusion is that by managing small remnant habitats to remain or become more semi-open and complex in their structure, would increase species richness of plants, grassland specialist species, and flower morphologies. It would also increase some ecosystem functions as seed predation and biologic pest control of aphids are more effective close to trees. If both midfield islets and forest borders would be managed to be semi-open, the area and connectivity of semi-open habitat would increase in the agricultural landscape, which may also improve pollination success as the connectivity between populations has a possibility to increase. Grassland specialist species are clearly abundant in the small remnant habitats. As the decline of semi-natural grasslands is causing a decline in grassland specialists’ species, not only plants, I recommend that small remnant habitats are included in conservation and management plans and strategies to improve habitat availability and connectivity for grassland species in agricultural landscapes.

Research funder Ekoklim. Project:4339602.

At the time of the doctoral defense, the following paper was unpublished and had a status as follows: Paper 4: Manuscript.

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Bock, Douglas Carl-Johan. "Wide Field Aperture Synthesis Radio Astronomy". University of Sydney. Physics, 1998. http://hdl.handle.net/2123/377.

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This thesis is focussed on the Molonglo Observatory Synthesis Telescope (MOST), reporting on two primary areas of investigation. Firstly, it describes the recent upgrade of the MOST to perform an imaging survey of the southern sky. Secondly, it presents a MOST survey of the Vela supernova remnant and follow-up multiwavelength studies. The MOST Wide Field upgrade is the most significant instrumental upgrade of the telescope since observations began in 1981. It has made possible the nightly observation of fields with area ~5 square degrees, while retaining the operating frequency of 843 MHz and the pre-existing sensitivity to point sources and extended structure. The MOST will now be used to make a sensitive (rms approximately 1 mJy/beam) imaging survey of the sky south of declination -30°. This survey consists of two components: an extragalactic survey, which will begin in the south polar region, and a Galactic survey of latitudes |b| < 10°. These are expected to take about ten years. The upgrade has necessitated the installation of 352 new preamplifiers and phasing circuits which are controlled by 88 distributed microcontrollers, networked using optic fibre. The thesis documents the upgrade and describes the new systems, including associated testing, installation and commissioning. The thesis continues by presenting a new high-resolution radio continuum survey of the Vela supernova remnant (SNR), made with the MOST before the completion of the Wide Field upgrade. This remnant is the closest and one of the brightest SNRs. The contrast between the structures in the central pulsar-powered nebula and the synchrotron radiation shell allows the remnant to be identified morphologically as a member of the composite class. The data are the first of a composite remnant at spatial scales comparable with those available for the Cygnus Loop and the Crab Nebula, and make possible a comparison of radio, optical and soft X-ray emission from the resolved shell filaments. The survey covers an area of 50 square degrees at a resolution of 43" x 60", while imaging structures on scales up to 30'. It has been used for comparison with Wide Field observations to evaluate the performance of the upgraded MOST. The central plerion of the Vela SNR (Vela X) contains a network of complex filamentary structures. The validity of the imaging of these filaments has been confirmed with Very Large Array (VLA) observations at 1.4 GHz. Unlike the situation in the Crab Nebula, the filaments are not well correlated with H-alpha emission. Within a few parsec of the Vela pulsar the emission is much more complex than previously seen: both very sharp edges and more diffuse emission are present. It has been postulated that one of the brightest filaments in Vela X is associated with the X-ray feature (called a `jet') which appears to be emanating from the region of the pulsar. However, an analysis of the MOST and VLA data shows that this radio filament has a flat spectral index similar to another more distant filament within the plerion, indicating that it is probably unrelated to the X-ray feature.

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Long, Emma. "The feeding ecology of Pteropus rufus in a remnant gallery forest surrounded by sisal plantations in south-east Madagascar". Thesis, University of Aberdeen, 2002. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=231933.

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Pteropus rufus, Madagascar's largest endemic fruit bat, is widely distributed but declining in number due to habitat loss and over-hunting. The roost of Berenty, located in a 250 ha remnant of gallery forest surrounded by 30,000 ha of sisal plantations and patches of endemic spiny forest, is the largest in southeastern Madagascar and is an important historical breeding site for this species. Compared with conspecifics elsewhere in Madagascar the diet of P. rufus at Berenty is narrow, containing only 17 plant species. Seven gallery forest and four cultivated species are consistently utilised by the bats, but no endemic spiny forest species were identified in their diet. Pollen of Agave sisalana, present in 84% of faecal samples, contains 36% protein, the main digestive extraction of which was high (73%). Native fruits provide more protein that cultivars, but the latter have significantly higher concentrations of soluble carbohydrates. P. rufus has high mean buccal extraction for nitrogen (73%); carbohydrates (86%); condensed tannins (46%) and phenolics (24%). However, contrary to expectation condensed tannin extraction had no significant effect on nitrogen extraction. P. rufus swallows more viable than non-viable Ficus seeds. In 92% and 58% of germination trials, bat-passed seeds had the highest percentage germination and fastest rate of germination, respectively, compared with seeds from ripe fruits, ejecta pellets or faeces of other frugivores. A minimum foraging range of 17 km was established. The role of P. rufus in pollination is inferred from the presence of pollen on the head and thorax of bats and in their faeces. P. rufus is therefore, an important seed disperser and potentially important pollinator. However, at Berenty its' heavy reliance on the introduced cultivator A. sisalana, unique among the Pteropodidae, suggests that without this resource the remaining gallery forest could not support such a large colony of P. rufus.

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Bittencourt, Juliana Vitoria Messias. "Genetic diversity and dynamics in remnant patches of Araucaria angustifolia forest in Paraná State, Brazil : implications for conservation and restoration". Thesis, University of Reading, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.494782.

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The objective of this study was to assess the genetic diversity and dynamics in remnant patches of Araucaria angustifolia forest, with different levels of human modification. The Araucaria forest is one of the most important biomes occurring naturally in southern Brazil. Extensive logging and agricultural expansion in the last century resulted in significant fragmentation of the forest cover. Molecular genetic markers (microsatellite), combined with population genetics and landscape ecology, were used to improve the understanding of the impact of fragmentation on the forest and to develop guidelines for habitat conservation and restoration.

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Alves, Jos? Ricardo. "Monitoramento de remanescentes florestais urbanos com ve?culo a?reo n?o tripulado". Pontif?cia Universidade Cat?lica de Campinas, 2017. http://tede.bibliotecadigital.puc-campinas.edu.br:8080/jspui/handle/tede/1118.

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Pontif?cia Universidade Cat?lica de Campinas - PUC - Campinas
The aim of this dissertation was to use current technology to collect environmental quantities of forests to perform a periodic monitoring that would aid in preventing the advance of degradation and deforestation of the urban forest remnants of Campinas, more specifically Mata do Quilombo, located in the Bar?o Geraldo district. The use of Unmanned Aerial Vehicles (UAV) in the diagnosis and preservation of this urban forest remnant provided a low-cost method and a non-invasive monitoring. The strategy was to use the UAV with embedded remotely-activated electronic sensors in order to collect units of environmental quantities such as the location of clearings within the forest created by deforestation, air temperature and humidity, luminosity and the georeferenced location of the study site. In addition to the UAV technology, wireless technology was also used to communicate with various frequency bands, thus validating the simultaneous operation of the embedded sensors without any interference between them or external sources. After the data was collected, the objective was to submit it to an outlier verification method and make them available in a monitoring center, so that the user could later save this information in a remote access system known as supervisory system.
Esse trabalho teve o intuito de utilizar tecnologias atuais para coleta das grandezas ambientais das matas para realizar um acompanhamento peri?dico dos remanescentes florestais urbanos de Campinas, mais especificamente a Mata do Quilombo, localizada no distrito de Bar?o Geraldo, que auxiliasse na preven??o do avan?o da degrada??o frequente e do desmatamento. A utiliza??o do VANT (Ve?culo A?reo N?o Tripulado) no diagn?stico e preserva??o desse remanescente florestal urbano proporcionou um m?todo de baixo custo e uma avalia??o de forma n?o invasiva. A estrat?gia visou utilizar o VANT com sensores eletr?nicos embarcados acionados remotamente afim de capturar unidades de grandezas ambientais como a localiza??o de clareiras no interior da mata provindas do desmatamento, temperatura e umidade do ar, luminosidade e localiza??o georreferenciada do local de estudo. Aliada ? tecnologia do VANT, tamb?m foi utilizada a tecnologia de comunica??o sem fio com diversas faixas de frequ?ncias, validando assim o funcionamento desses sensores embarcados em atividade simult?nea sem que houvesse interfer?ncias entre os mesmos e de meios externos. Ap?s a coleta, o intuito foi submeter os dados coletados a um tratamento de verifica??o de outlier (m?todo de descarte de dados que se distanciam dos demais) e disponibiliz?-los numa central de monitoramento, de forma que o usu?rio pudesse salvar essas informa??es posteriormente num servidor de acesso remoto conhecido como sistema supervis?rio.

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Hansen, Simone. "How flower visitation of remnant grassland patches is affected by commercial timber plantations and an invasive alien species (Rubus cuneifolius)". Thesis, Stellenbosch : Stellenbosch University, 2015. http://hdl.handle.net/10019.1/98051.

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Thesis (MSc)--Stellenbosch University, 2015.
ENGLISH ABSTRACT: Our planet is in the midst of a biodiversity crisis, with factors such as land transformation, climate change, anthropomorphic disturbance and invasive species acting together to threaten biodiversity. In South Africa, with minimal natural wood resources, commercial forestry is one of the most abundant forms of landscape transformation. However, a third of the land inside many plantations has been set aside for conservation as unplanted remnant grassland patches (RGPs). These areas are subjected to an additional negative impact by invasive alien species, namely Rubus cuneifolius (American bramble), a weed that is particularly problematic in and around forestry plantations in South Africa. The grassland biome of South Africa is extremely diverse and is of vital importance for the ecosystem services it supplies. Despite this, the grassland biome is under threat as this is where much of South Africa’s forestry plantations are located. Driven by anthropomorphic disturbance, pollinators are in decline. Landscape transformation of natural areas for forestry plantations is likely to affect plant-pollinator interactions which will affect ecosystems and biodiversity. However, it is not known to what extent these ecosystems are affected. It is thought that the impact depends on the complexity of the ecosystem in question, and analyses at the network-level provide insights into the robustness of ecosystems in the face of biodiversity loss. Thus, this study evaluates the effect of natural habitat fragmentation and invasion of the alien species, R. cuneifolius, on flower visitation networks of South African grasslands. The study was conducted in the KwaZulu-Natal Midlands within a commercial timber plantation and a neighbouring protected area (PA). Flower-visitor observations were carried out in uninvaded protected areas and RGPs and in protected areas and RGPs invaded by R. cuneifolius. I found that RGPs within commercial forestry plantations successfully decrease the negative effects of land transformation on the grasslands of the KwaZulu-Natal Midlands, and flower visitation network patterns are largely maintained in these habitat fragments. However, within RGPs, invasion by R. cuneifolius affected the composition and the interaction network structure of flower-visitor and plant communities. The fact that there are unplanted areas within commercial forestry plantations is positive for biodiversity conservation in South Africa. Research has indicated that these areas successfully aid in the conservation of biodiversity and ecosystem functioning. Due to the positive influence that RGPs have on conservation in fragmented and transformed landscapes, it is critical that these unplanted areas are retained. However, the effects of bramble invasion are more intense within RGPs than within protected areas, and therefore, it must be a priority to keep these areas undisturbed. R. cuneifolius has been found to have devastating effects on ecosystem function and network structure. It is also a category 1 invasive plant within South Africa, and its removal is required by law. Therefore, the removal of bramble must be a management priority.
AFRIKAANSE OPSOMMING: Ons planeet is in die middel van 'n biodiversiteit krisis, met faktore soos grond transformasie, klimaatsverandering, antropomorfiese versteuring en indringerspesies wat gesamentlik werk om biodiversiteit te bedreig. Suid-Afrika, besit minimale houtbronne. Daarom is kommersiële bosbou een van die mees algemene vorme van landskap transformasie. Tog is 'n derde van die land binne baie plantasies opsy gesit vir bewaring as oorblywende grasveld kolle (OGKs). Hierdie gebiede word ongelukkig blootgestel aan die bykomende negatiewe impak van die uitheemse spesies, Rubus cuneifolius (Amerikaanse steekdoring), wat veral problematies is in en rondom bosbouplantasies. Die grasveldbioom van Suid-Afrika is baie divers en is van kardinale belang vir die ekosisteem dienste wat dit lewer. Ten spyte hiervan, word die grasveldbioom bedreig waar dit op dieselfde areas as die meerderheid van Suid-Afrika se bosbouplantasies geleë is. Antropomorfiese versteuring lui daartoe dat bestuiwergetalle daal. Landskap transformasie vir bosbou plantasies raak dus plant-bestuiwer interaksies, wat ekosisteme en biodiversiteit beïnvloed. Dit is nie bekend tot watter mate hierdie ekosisteme geraak word nie. Daar word vermoed dat die impak af hang van die kompleksiteit van die ekosisteem. Ontledings van ekosisteme op netwerk vlak kan insigte bied oor die robuustheid van hierdie ekosisteme in die aangesig van biodiversiteitverlies. Dus, die studie evalueer die effek van fragmentasie van natuurlike habitatte en inval van die indringer spesie, R. cuneifolius, op blom-besoekings netwerke van Suid-Afrikaanse grasvelde. Hierdie studie is uitgevoer in die KwaZulu-Natal Midlands binne 'n kommersiële hout plantasie en 'n naburige beskermde gebied (BG). Blom-besoeker waarnemings was in BGs en OGKs sonder R. cuneifolius, en in BGs en OGKs met R. cuneifolius uitgevoer. Ek het gevind dat OGKs binne kommersiële bosbouplantasies suksesvol is om die negatiewe uitwerking van land transformasie te verminder, en blom-besoeking netwerk patrone grootliks gehandhaaf word in hierdie habitat fragmente. Egter, binne OGKs, het R. cuneifolius die samestelling en die interaksie netwerk struktuur van blom-besoekers en plant gemeenskappe negatief geraak. Die feit dat OGKs ongeplant gelaat word, is positief vir die bewaring van biodiversiteit in Suid- Afrika. Navorsing dui aan dat hierdie gebiede suksesvol is om te help met die bewaring van biodiversiteit en ekosisteemfunksionering. As gevolg van die positiewe invloed van OGKs op bewaring in gefragmenteerde en omskepte landskappe, is dit krities dat hierdie areas ongeplant bly. Egter, die gevolge van steekdoring inval is meer intens binne OGKs as binne beskermde gebiede, en daarom moet dit 'n prioriteit wees om hierdie gebiede ongestoord te hou. R. cuneifolius se verwoestende uitwerking op ekosisteem funksie en netwerk struktuur was baie duidelik. Dit is ook 'n kategorie 1 indringerplant in Suid-Afrika, en sy verwydering word deur is die wet vereis. Daarom moet die verwydering van steekdoring ‘n bestuursprioriteit wees.

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Shiponeni, Ndafuda Nangula. "Dispersal of seeds as a constraint in revegetation of old fields in Renosterveld vegetation in the Western Cape, South Africa". Thesis, Stellenbosch : Stellenbosch University, 2003. http://hdl.handle.net/10019.1/53396.

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Thesis (MScFor )--Stellenbosch University, 2003.
ENGLISH ABSTRACT: Species-rich Renosterveld vegetation does not return to old agricultural fields even after many years (10-20) of abandonment. In most cases the fields are slowly taken over by non-indigenous species, particularly alien pasture grasses and African lawn grass. While poor survival of indigenous seedlings due to competition, grazing or any other establishment constraints, might explain the failure of natural vegetation to colonise old fields, here I am testing the hypothesis that recolonisation by indigenous plant species is limited by seed dispersal. I have quantified changes in seed density with distance from the natural vegetation into old fields using seed traps and soil seed bank assessment. I have also looked at seed dispersal in the dung of large herbivores. Shrubs (with the exception of Eytropappus rhinocerotis) were poorly represented in the seed rain indicating that they might be seed limited. Dicerothamnus rinocerotis (a dominant shrub in Renosterveld) and certain geophytes (that were recovered in the soil bank) have proven that seed dispersal is not the primary constraint to their return to ploughed fields. Dicerothamnus rinocerotis produces a large number of seeds that are dispersed long distances into the old field and a number of geophytes were well represented in the soil bank. Large herbivores are dispersing a lot of herbaceous forbs in their dung but make very little contribution to the dispersal of indigenous tussock grass and shrubs. Seeds of indigenous Renosterveld tussock grasses (e.g Tribolium hispidum) were restricted to the edge of the natural vegetation. My research has shown that some indigenous seeds, particularly those dispersed in wind and through large mammals, do reach the old ploughed field. I therefore conclude that seed dispersal is not the primary constraint to the natural recovery of populations of some indigenous plant species on old fields, but may limit recovery of certain indigenous geophytes, grasses and shrubs.
AFRIKAANSE OPSOMMING: Spesie-ryke Renosterveld plantegroei hervestig nie op ou landerye nie, selfs ná baie jare (l0-20) van verlating. Oor die algemeen word hierdie grond stadig oorgeneem deur uitheemse spesies, veral uitheemse weidingsgrasse en kweekgras. Terwyl swak oorlewing van inheemse saailinge as gevolg van kompetisie, weiding of enige ander vestigingsbeperkinge, die mislukte vestiging van natuurlike plantegroei op ou benutte grond kan verduidelik, toets ek hier die hipotese dat hervestiging deur inheemse plantspesies deur saadverspreiding beperk word. Ek het veranderinge in saaddigtheid oor afstand vanaf die natuurlike plantegroei na ou landerye gekwantifiseer, deur gebruik te maak van saadopvangsvalle en sand saadbank beraminge. Ek het ook gekyk na saadverspreiding in die mis van groot herbivore. Struike (behalwe Eytropappus rhinocerotis) was swak verteenwoordig in die "saadreën", wat mag toon dat struike saadbeperk is. Eytropappus rhinocerotis ('n dominante struik in Renosterveld) en sekere geofiete (wat in die saadbank gevind is) het bewys dat saadverspreiding nie die hoofbeperking is vir hulle terugkeer na geploegde lande nie. Eytropappus rhinocerotis produseer 'n groot hoeveelheid saad wat oor groot afstande oor die ou landerye versprei word en 'n aantal geofiete was goed verteenwoordig in die saadbank. Groot herbivore versprei 'n groot hoeveelheid kruidagtige forbe in hulle mis, maar maak 'n baie klein bydrae tot die verspreiding van inheemse polgras en struike. Saad van inheemse Renosterveld polgrasse (bv. Tribolium hispidum) was beperk tot die some van die natuurlike plantegroei. My navorsing het getoon dat sommige inheemse saad, veral dié wat deur die wind en deur groot herbivore versprei word, wel die ou geploegde landerye bereik. Ek maak dus die gevolgtrekking dat saadverspreiding nie die hoofbeperking is vir die natuurlike herstel van populasies van sommige inheemse plantspesies op ou landerye nie, maar mag die herstel van sekere inheemse geofiete, grasse en struike beperk.

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Doody, Brendan J. "Riccarton Bush and the natural and social realities of native trees in Christchurch, New Zealand". Lincoln University, 2008. http://hdl.handle.net/10182/865.

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Urbanization has destroyed and fragmented previously large areas of natural habitat. Small remnants that still exist in numerous cities will be unable to sustain many viable wild plant populations if they do not expand into the surrounding urban matrix. Residential gardens surrounding such remnants, and which form a significant component of urban green space in many cities, could play a role in redressing this problem. Riccarton Bush, a 7.8 hectare forest remnant, and its surrounding suburban residential area, in Christchurch, New Zealand, is a good example. Over 125 years the reported number of native vascular plants in the bush has declined by a third. My study was an attempt to understand: 1) the ecological, social and cultural factors influencing the dispersal and regeneration of 12 native bird-dispersed woody species from Riccarton Bush, into surrounding residential properties; and 2) the potential role residential properties could play in the future of the bush. To examine these diverse factors I adopted an interdisciplinary research approach combining methodologies, concepts and theories from ecology and the social sciences. In a broader context my work was an attempt to demonstrate how urban ecology can further develop and strengthen by adopting and integrating new methodologies, theories and concepts. The ecological component involved recording individuals of the study species found on 90 randomly selected properties within a 1.4 km radius of the bush. Soil samples were also collected from 31 of those properties and placed in a glasshouse and the study species that germinated were recorded. Results showed some species, particularly kahikatea (Dacrycarpus dacrydioides), the most abundant species in the bush, are being dispersed and establishing on properties predominantly within 250 m of the forest margin. These juveniles are not reaching maturity as most gardeners tend to remove all non-planted woody species. Qualitative interviews with 16 residents and a quantitative survey of the residents of 85 of the properties provided insights into the social context which these natural processes were operating. Using notions of place and performance I argue that gardens are continuously created and recreated by humans and non-humans. Residents attempt to create and maintain a garden that fulfils their individual and familial needs and desires (e.g., aesthetics, leisure and privacy), and public responsibilities such as ensuring they have a ‘neat’ and ‘tidy’ garden. This involves selecting plants for colour, shape and the care they require, and encouraging certain performances (e.g., flowering) while controlling other undesirable plants and performances (e.g. growth, spread and shading). While people make connections between native plants, belonging and identity; the ‘scientific’ demarcation between native and exotic species often becomes obscured as the garden is co-created by people and plants. Some plants become more significant than others but usually this is attributable to their performances rather than whether they are native or exotic. Residential gardens have the potential to play a major role in the conservation of species restricted to urban remnants. My research suggests that although the potential exists for woody species restricted to Riccarton Bush to naturally regenerate in nearby gardens, this will not happen without human intervention. Plants will need to be eco-sourced and propagated to avoid detrimental impacts on the genetic health of remnant populations, and then actively planted in gardens. The success of such planting initiatives will be increased by providing residents with information about the plants that are suitable for their performative needs and desires (e.g., the size, colour, and maintenance requirements of plants) and, most importantly, control over the location of plantings. In concluding, I argue that by adopting new concepts, theories and methodologies, the productivity, creativity and relevance of urban ecology can be significantly enhanced.

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Aragundi, León Sheika. "Biogeographic study of the Polylepis forest remnants of the northeastern Cordillera Oriental of Ecuador and implications for their conservation". 2008. http://purl.galileo.usg.edu/uga%5Fetd/león%5Fsheika%5Fa%5F200812%5Fphd.

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Hutchison, Melissa Alice Sarah. "Interactions between habitat fragmentation and invasions : factors driving exotic plant invasions in native forest remnants, West Coast, New Zealand : a thesis submitted in partial fulfillment of the requirements of the degree of Doctor of Philosophy in Ecology, School of Biological Sciences, University of Canterbury /". 2008. http://hdl.handle.net/10092/3218.

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39

Comtois, Michèle. "Camp et Forêt suivi de Quatre objets de mémoire". Thèse, 2012. http://hdl.handle.net/1866/9200.

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Camp met en présence un officier nazi et ses Juifs : une petite fille s’appuyant sur sa vie d’avant afin de survivre dans sa vie d’après, une jeune femme d’une cinglante liberté intérieure et un groupe de prisonniers, la masse grise. Ce récit se déroule en quelques jours dans un camp d’extermination, en Pologne. Il y est question d’un projet insensé, imaginé et mis en œuvre par le Nazi dont le discours s’apparente à de confuses et dérisoires logorrhées. La recherche d’une humanité déniée, à la base du dévoilement de l’individualité des personnages (prisonniers), émane de la grâce, de l’authenticité et de la force vitale de la protagoniste, la petite fille, tendue vers son plan-de-quand-même-vie. Forêt, écrit en parallèle, puis à la fin de Camp, n’est pas sa suite, mais l’est aussi… Court récit poétique, il raconte la traversée d’une forêt par une femme à la recherche de ses édens. Le lieu, interpellé et très souvent conspué pour ce qu’il est devenu, devient un actant. Forêt, se servant de ses restes mythiques, contraint le pas-à-pas de la femme, perdue d’avance. L’essai, Quatre objets de mémoire, porte sur l’appropriation et la transmission de la mémoire de la Shoah, à partir de restes, de détails, de petits riens, perçus ici comme d’imaginables traces. J’interroge les signes singuliers d’improbables objets (feuillets administratifs du Troisième Reich, clichés fragmentaires d’Auschwitz-Birkenau et photographies de ses bois et de ses latrines) afin d’y débusquer de petits morceaux du caché, du secret et de l’innommable de la Solution finale. L’affect ressenti en présence de ces objets, par ce que je nomme, le nécessaire abandon, y est analysé dans le dessein d’en saisir leurs douleurs et de les rendre miennes. L’œuvre de l’artiste de la photo, Marie-Jeanne Musiol, sur Auschwitz-Birkenau, est à la base de ce désir de mémoire pérenne.
Camp presents a Nazi officer and his Jews : a little girl leaning on her previous life so that she’ll survive in her afterwards life, a young woman livened up by a pungent inner freedom and a group of prisoners, the grey herd. This story takes place within few days inside an extermination camp, in Poland. It is about an insane plan, envisioned and implemented by the Nazi whose discourse is similar to muddled and vacuous logorrheas. At the very roots of the unveiling of the character’s individuality (the prisoners), the quest for a denied humanity emanates from the grace and the vital force of the protagonist, the little girl, towards her plan-of-anyhow-life. First written in parallel then in the end, Forêt is not the continuation of Camp even if it is, as well… This brief poetical narrative relates a woman’s crossing of a forest while searching for her Edens. Hailed and quite often jeered for what it became, the site turns into an actant. Through its mythical remnants, Forest ergo compels the woman’s doomed step-by-step. The essay Quatre objets de mémoire focuses on the appropriation and transmission of the memory of the Holocaust through remnants, details, small things regarded here as imaginable traces. I examine quaint signs of unlikely objects (Third Reich’s administrative leaflets, Auschwitz-Birkenau’s fragmented pictures and images of its woods and latrines) in order to disclose small pieces of what is the hidden, the secretive and the unspeakable about the Final Solution. The affect experienced upon their contact, through what I call the “necessary abandonment”, is thusly analyzed with the purpose to comprehend the corresponding pains and to seize them for myself. Photo Artist Marie-Jeanne Musiol’s work on Auschwitz-Birkenau underlies this perennial desire to remember.

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Huang, Jheng-Yu, i 黃正宇. "Remnant Trees and Surrounding Vegetation Influence Avian Frugivores Visitation in Forest Restored Sites in Taiwan". Thesis, 2014. http://ndltd.ncl.edu.tw/handle/36050543617215723886.

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碩士
國立臺灣大學
森林環境暨資源學研究所
102
Human exploitation is the major threat to forests worldwide, which resulted in severe forest loss and degradation and compelling need of forest restoration. Due to the limitation of planting seedlings, effective forest restoration strategy should combine both human planting and accelerating natural recovery. The visitation of avian frugivores to a site is thought to be positively correlated with seed rain. Therefore, more visits of avian frugivore to restored site should increase input of seed rain, which promotes forest restoration. In this study, I monitored avian frugivore visitation in 30 forest restored sites within Experimental Forest of National Taiwan University in Nantou. As my results, avian frugivore species richness was positively related with tree species diversity. Avian frugivore visitation rate was positively related with tree species diversity and foliage volume of remnant trees, and negatively related with conifer plantation coverage in surrounding landscape. However, the effect of remnant trees differed as landscape structure changed. In area dominated by conifer plantations, the effect of remnant tree was limited, and few frugivore species appeared in the restored sites. Some Frugivore species showed different habitat associations in restored sites. Black Bulbul (Hypsipetes leucocephalus) and White-eared Sibia (Heterophasia auricularis) were relatively general in different restored sites. Entering ratio of avian frugivore differed among species and seasons. Shrub-dwelling frugivore species rarely entered restored sites. However, tree frugivore species entered restored sites more often except Taiwan barbet (Megalaima nuchali), and their entering ratios increased dramatically during the non-breeding season. My results suggest more diverse and dense structure of remnant tree is more effective on attracting avian frugivores to restored sites. However, for restored sites within conifer plantations, remnant trees would become less effective and more human efforts are needed to promote forest recovery. Black bulbul and White-eared Sibia are important seed dispersers in restored sites, and some frugivore specie would enter more frequently during non-breeding season, which may result in higher abundance of seed rain.

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Zeppel, M. "The influence of drought, and other abiotic factors on tree water use in a temperate remnant forest". Thesis, 2006. http://hdl.handle.net/10453/37299.

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University of Technology, Sydney. Faculty of Environmental Sciences.
This thesis presents the results of work undertaken to examine daily, seasonal and annual patterns of water use by a native remnant woodland in temperate Australia. The focus of the study was on the two dominant tree species of the woodland, but limited assessments of understorey and soil evapotranspiration were also undertaken. One of dominant species was Eucalyptus crebra, a broad-leaved tree and the other was Callitris glaucophylla a needle-leaved tree. At the start of the study, much of the eastern seaboard of Australia experienced a severe and prolonged drought but towards the end of the field work, rainfall at the site was significantly larger than the long-term average. This provided a fortuitous opportunity to compare the responses of vegetation water use to drought and nondrought periods. The study was conducted on the Liverpool Plains, of western New South Wales, Australia. Principle methods applied were (a) use of heat-pulse technology to measure rates of sap flow through trees; (b) open-top chambers to measure understorey and soil evapotranspiration; (c) application of the Penman-Monteith equation to estimate canopy conductance and transpiration rates; (d) two methods to scale spatially from measurements of individual trees to estimates of stand water use; (e) three methods to scale temporally from measurements conducted over a few weeks each year to provide annual estimates of stand water use; (f) a simple water balance was constructed to approximate the rate of deep drainage of water (rate of recharge). An annual water budget for the site was estimated for the drought and post-drought periods. The relationship between tree water use and diameter at breast height (DBH) was similar for the two species in each season, but the relationship for both species differed between seasons and years. In contrast, the relationships amongst DBH, sapwood area and leaf area differed between species at all times. This suggests that the same rate of water use by the eucalypt and Callitris (at a common size) was achieved through different mechanisms. Daily rates of stand water use showed significant intra- and inter-seasonal variation, with the lowest rates observed in winter and largest rates in summer. A simple model based upon solar radiation and vapour-pressure deficit was able to account for approximately 80 % of variation of stand water use under summer conditions with wet soil. Estimates of stand water use derived from the Penman-Monteith equation generally agreed well with those based upon measurements of sap velocity, with a slope of the regression of the two estimates being 1.03. In the drought-year, stand water use was approximately 59 % of rainfall and recharge was approximately 2% but in the post-drought year, when rainfall doubled compared to the drought year, stand water use was also 59 % whereas recharge was 4 %. This showed that despite the impact of an extensive and pronounced drought, the trees were able to rapidly adjust to more favourable conditions and maintain a low rate of recharge. These results are discussed in relation to the management of water resources for human consumptive use and in relation to the development of dryland salinity across Australian landscapes that have been cleared of trees.

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42

Vera, Paula. "Fire history and ecology of remnant forest patches in the Sub-Boreal Pine-Spruce zone of central British Columbia". Thesis, 2001. http://hdl.handle.net/2429/11597.

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When a fire burns a substantial area of forest, it often leaves patches unburned. No published study appears to have addressed the question of whether or not there are patches that have never been burned by fires within the last few hundred years in British Columbia. Published studies have only partially addressed the question of whether or not there are some landscape factors that prevented fire from killing trees within the unburned patches. To address these questions, a project commenced in 1999 in the SBPSxc biogeoclimatic subzone with 2 main objectives - to determine (1) if there are some forest patches within lodgepole pine forests in this subzone in central B.C. that have not burned during the last 200-300 years, and (2) if forest patches within these lodgepole pine forests that did not burn at the time when the surrounding forests were most recently burned, have some characteristics that caused them not to burn. It was determined that in 24 of 26 patches studied, the most recent fire within the patch was the same one that established the surrounding forest. All patches had burned within the last 200-300 years. It is not completely certain why trees in the study patches escaped being killed during the fire that established the surrounding forest. It appears that lower tree density and basal area within the patches at the time of the fire may have been important. Other factors such as topographic features, soil moisture, and crown fuels do not appear to have been important.

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Goslin, Matthew N. "Development of two coniferous stands impacted by multiple, partial fires in the Oregon Cascades : establishment history and the spatial patterns of colonizing tree species relative to old-growth remnant trees /". 1997. http://hdl.handle.net/1957/12073.

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Galasso, Louise. "The spectacled bear's impact on livestock and crops and use of remnant forest fruit trees in a human-altered landscape in Ecuador". 2002. http://digital.library.wisc.edu/1793/7588.

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45

Gooch, Scott. "Effects of white-tailed deer herbivory on a tallgrass prairie remnant". 2010. http://hdl.handle.net/1993/3847.

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A study was conducted to determine what impact high white-tailed deer (Odocoileus virginianus) densities were having on the native grasslands of a tallgrass: aspen forest tract embedded within an agro-urban setting. Due to excessive spring moisture, row-crops were unavailable the first year. Using microhistological fecal analysis to determine dietary composition, deer were assessed to be placing the site’s favoured native plant species at risk of extirpation. Measuring woody stem abundance and height along and near the prairie: forest ecotone, deer were found to restructure woody growth but not directly influence encroachment rates. Indirectly, however, deer facilitated forest encroachment and prairie degradation through seed dispersal, nitrogen deposition, gap-dynamics, and trampling. Comparing dietary composition to nutritional data, deer grazed to maximize fitness, selecting foods high in IVDMD, minimizing energy expenditure, and optimizing CP. High crop CP was offset by intensively grazing particular native plants. ADF was an effective nutritional marker, not AIA.

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Wilson, Anne-Marie. "Linking science, policy and practice in the conservation of woodland birds in a rural landscape : a case study in the South-West Slopes, New South Wales, Australia". Phd thesis, 2003. http://hdl.handle.net/1885/148277.

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Maas, Bea. "Birds, bats and arthropods in tropical agroforestry landscapes: Functional diversity, multitrophic interactions and crop yield". Doctoral thesis, 2013. http://hdl.handle.net/11858/00-1735-0000-0022-5E77-5.

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