24 research outputs found

    Microclimate affects landscape level persistence in the British Lepidoptera

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    Microclimate has been known to drive variation in the distribution and abundance of insects for some time. Until recently however, quantification of microclimatic effects has been limited by computing constraints and the availability of fine-scale biological data. Here, we tested fine-scale patterns of persistence/extinction in butterflies and moths against two computed indices of microclimate derived from Digital Elevation Models: a summer solar index, representing fine-scale variation in temperature, and a topographic wetness index, representing fine-scale variation in moisture availability. We found evidence of microclimate effects on persistence in each of four 20 × 20 km British landscapes selected for study (the Brecks, the Broads, Dartmoor, and Exmoor). Broadly, local extinctions occurred more frequently in areas with higher minimum or maximum solar radiation input, while responses to wetness varied with landscape context. This negative response to solar radiation is consistent with a response to climatic warming, wherein grid squares with particularly high minimum or maximum insolation values provided an increasingly adverse microclimate as the climate warmed. The variable response to wetness in different landscapes may have reflected spatially variable trends in precipitation. We suggest that locations in the landscape featuring cooler minimum and/or maximum temperatures could act as refugia from climatic warming, and may therefore have a valuable role in adapting conservation to climatic change

    Climate change refugia for the flora and fauna of England

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    A variety of evidence suggests that species have, in the past, been able to withstand the effects of climatic change in localised environments known as refugia, where specific environmental conditions acted as a buffer against broader-scale climatic changes. Therefore, an important question for conservation is whether refugia might exist under current and future anthropogenic climate change. If there are areas that are likely to remain relatively climatically stable and so enable species to persist despite climate change making surrounding areas unsuitable, identifying and protecting these places will be an important part of future conservation strategies. This report is part of a project that is investigating this question. The report was commissioned to identify the characteristics of potential refugia, to investigate evidence for the existence of contemporary refugia by analysing patterns of local persistence and disappearance of over 1000 species across a range of taxa, and to identify sites in England with the potential to function as refugia for different taxonomic groups at a range of spatial scales

    Terrestrial and Freshwater Ecosystems and Their Services (Chapter 2)

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    Chapter 2, building on prior assessments1, provides a global assessment of the observed impacts and projected risks of climate change to terrestrial and freshwater ecosystems, including their component species and the services they provide to people. Where possible, differences among regions, taxonomic groups and ecosystem types are presented. Adaptation options to reduce risks to ecosystems and people are assessed

    Temporal dynamics of the shrub and herbaceous layer of an area of moist grassland in Alto Paraíso de Goiás, Brazil

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    Este trabalho avaliou a dinâmica estrutural e fl orística de uma comunidade de espécies herbáceo-arbustivas de uma área de campo limpo úmido em Alto Paraíso de Goiás, o primeiro inventário realizado em 2000 (T0) e o segundo em 2007 (T1). A diversidade de Shannon entre os períodos foi comparada pelo teste-t de Hutcheson e a similaridade fl orística, pelo índice de similaridade de Chao-Sørensen. As relações fl orísticas e a cobertura, entre os períodos e as linhas, foram avaliadas por meio de análises de correspondência retifi cada (DCA). Foram amostradas 98 espécies, 88 no T0 e 67 no T1, sendo 31 exclusivas do T0 e 10 do T1. A diversidade fl orística na comunidade foi elevada nos dois períodos, porém diferente entre esses (t = 7,12; p < 0,001), devido a variação no número e cobertura das espécies. A similaridade entre os dois inventários foi alta (Chao-Sørensen ± IC = 0,841 ± 0,074). A ordenação por DCA indicou relações entre a composição fl orística e a cobertura com o gradiente de umidade e de matéria orgânica no solo identifi cados em T0. Houve modifi cações nas linhas em zonas sazonais, as quais se tornaram mais semelhantes às linhas constantemente saturadas por água. Em um intervalo de sete anos o campo limpo úmido apresentou mudanças na composição fl orística e, principalmente na estrutura devido o aumento da cobertura de espécies perenes, cespitosas e entouceiradas, que foram favorecidas pela maior umidade no solo em resposta à elevação da pluviosidade da região. __________________________________________________________________________________________ ABSTRACTTh is study evaluated the fl oristic and structural dynamics of a community of herbaceous-shrub species in an area of moist grassland in Alto Paraíso de Goiás. Th e fi rst inventory was undertaken in 2000 (T0) and the second in 2007 (T1). Shannon’s diversity between the periods was compared by Hutchesons´s t-test, and the fl oristic similarity by the Chao-Sørensen similarity index. Floristic composition and cover, between periods and lines, were evaluated by detrended correspondence analysis (DCA). We sampled 98 species, 88 at T0 and 67 at T1; 31 were unique to T0 and 10 to T1. Floristic diversity in the community was high in both periods, but diff erent between them (t = 7.12, p <0.001), due to variation in species number and coverage. Similarity between the two surveys was high (Chao-Sørensen CI = ± 0.841 ± 0.074). Th e DCA ordination indicated relationships between the fl oristic composition and cover with a gradient of moisture and organic matter in the soil identifi ed in T0. Th ere were changes in the lines in the seasonal zones, which became more similar in those constantly saturated with water. During an interval of seven years the moist grassland showed changes in fl oristic composition and mainly in structure due to increased cover of the clumped tussock perennial species, which were favored by higher soil moisture due to high rainfall in the region

    Countryside Survey - Environmental Change Network link

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    The flowers of the forest

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