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This study uses species distribution modeling and physiological and functional traits to predict the impacts of climate change on native freshwater fish in the Murray-Darling Basin, Australia. We modelled future changes in taxonomic and functional diversity in 2050 and 2080 for two scenarios of carbon emissions, identifying areas of great interest for conservation. Climatic-environmental variables were used to model the range of 23 species of native fish under each scenario. The consensus model, followed by the physiological filter of lethal temperature was retained for interpretation. Our study predicts a severe negative impact of climate change on both taxonomic and functional components of ichthyofauna of the Murray-Darling Basin. There was a predicted marked contraction of species ranges under both scenarios. The predictions showed loss of climatically suitable areas, species and functional characters. There was a decrease in areas with high values of functional richness, dispersion and uniqueness. Some traits are predicted to be extirpated, especially in the most pessimistic scenario. The climatic refuges for fish fauna are predicted to be in the southern portion of the basin, in the upper Murray catchment. Incorporating future predictions about the distribution of ichthyofauna in conservation management planning will enhance resilience to climate change.

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ABSTRACT. Forest fragmentation may negatively impact fauna and flora. An important tool for the development and implementation of research on these effects is the use of a geographic information system (GIS). This paper aims to perform an integrated analysis of the landscape fragments that compose the Alonzo River watershed, Paraná State, by using remote sensing tools and landscape ecology metrics. The analyzed landscape metrics were Patton's index, total area of the patches, edge length, edge density, forest fragment density, and the core area of the patches. The results showed 888 forest patches with area values ranging from 0.15 ha to 2509.82 ha, and it represents 12.5% of the total forest land cover of the studied basin; this means that 85.3% of the forest patches are less than 50 ha and that 75% of those fragments have a Patton's index value of less than 3.9. The fragments that compose the studied area may be subject to edge effects and biodiversity loss as long as they present reduced areas and small core areas. Thus, the use of GIS and landscape ecology metrics is a quick and efficient way to evaluate the effect of fragmentation over large areas.Keywords: conservation; connectivity; GIS. Dimensões espaciais de métricas da paisagem de remanescentes da Mata Atlântica no Estado do Paraná, Brasil RESUMO.A fragmentação florestal pode exercer influências negativas sobre a fauna e da flora. Uma importante ferramenta para o desenvolvimento e aplicação de trabalhos sobre efeito da fragmentação florestal é o uso de Sistema de Informação Geográfica (SIG). Esta pesquisa objetivou analisar fragmentos que compõem a bacia hidrográfica do rio Alonzo no Estado do Paraná, usando ferramentas de geoprocessamento e métricas em ecologia de paisagem. As métricas analisadas foram o índice de Patton, área total dos fragmentos, comprimentos de borda, densidade de borda, densidade dos fragmentos florestais e área de núcleo dos fragmentos. Os resultados mostraram 888 fragmentos florestais com valores de área variando de 0,15 ha até 2.509,82 ha, o que representa 12,5% da cobertura vegetal total da bacia estudada, da qual 85,3% dos fragmentos possuem área inferior a 50 ha, e 75% com o índice de Patton inferior a 3,9. Os fragmentos que compõem a área de estudo estão sujeitos à influência do efeito de borda e perda de biodiversidade, pois apresentam reduzidas áreas e, consequentemente, menor área de núcleo. Dessa forma, o uso de SIG e métricas de ecologia de paisagem é uma forma rápida e eficiente de avaliação do efeito da fragmentação em grandes áreas.