Loss, fragmentation and decreasing quality of habitats have been proposed as major threats to biodiversity world-wide, but relatively little is known about biodiversity responses to multiple pressures, particularly at very large spatial scales. We evaluated the relative contributions of four landscape variables (habitat cover, diversity, fragmentation and productivity) in determining different components of avian diversity across Europe. We sampled breeding birds in multiple 1-km 2 landscapes, from high forest cover to intensive agricultural land, in eight countries during 2001−2002. We predicted that the total diversity would peak at intermediate levels of forest cover and fragmentation, and respond positively to increasing habitat diversity and productivity; forest and open-habitat specialists would show threshold conditions along gradients of forest cover and fragmentation, and respond positively to increasing habitat diversity and productivity; resident species would be more strongly impacted by forest cover and fragmentation than migratory species; and generalists and urban species would show weak responses. Measures of total diversity did not peak at intermediate levels of forest cover or fragmentation. Rarefaction-standardized species richness decreased marginally and linearly with increasing forest cover and increased non-linearly with productivity, whereas all measures increased linearly with increasing fragmentation and landscape diversity. Forest and open-habitat specialists responded approximately linearly to forest cover and also weakly to habitat diversity, fragmentation and productivity. Generalists and urban species responded weakly to the landscape variables, but some groups responded non-linearly to productivity and marginally to habitat diversity. Resident species were not consistently more sensitive than migratory species to any of the landscape variables. These findings are relevant to landscapes with relatively long histories of human land-use, and they highlight that habitat loss, fragmentation and habitat-type diversity must all be considered in land-use planning and landscape modeling of avian communities.
RESUMOO estudo do meio físico de uma bacia hidrográfica é condição básica para o planejamento bem sucedido da preservação da mata ciliar e conservação e produção de água. Os objetivos do presente trabalho foram analisar e quantificar a evolução espacial e temporal (1984 e 2010) através de imagens de satélite Landsat-5, da sub-bacia do córrego do Cintra, Botucatu SP, processadas pelo sistema computacional IDRISI Andes, e analisar a qualidade da água pelos parâmetros pH, CE, OD e a DBO 5 em 4 pontos distintos nos anos de 1999, 2008 e 2009. Considerando a área de 1076,48ha da sub-bacia, observou-se que a classe pastagem em 1984 foi reduzida em 25,55% em 2010 resultando no aumento das demais classes. A mais importante foi a classe mata nativa e reflorestamento, pois aumentou 5,08%, o que demonstra recuperação da mata ciliar. Foram identificadas áreas degradadas situadas no limite inferior da sub-bacia (P 3 e P 4 ) e contaminação pontual (P 1 e P 2 ) com piora na qualidade da água nos demais pontos nos períodos de 2008 e 2009. Restauração e manejo de sucessão ecológica nas áreas degradadas e o monitoramento da qualidade da água nos pontos 1 e 2 serão necessários para restabelecer a condição natural na área de estudo.
The original article presented a summary of the results and conclusions of a Comparative Test conducted within the scope of RILEM TC 189-NEC ''Non destructive Evaluation of the Concrete Cover''. The Comparative Test (CT) was intended to assess, under the same conditions, the performance of different non-destructive test (NDT) methods 2 Curing and pre-conditioning of the slabs All slabs were initially stored in a moist room (20°C, 90% RH) for 24 h. Subsequently they were demoulded and treated as detailed below. *This document has been prepared by R. Torrent chairman of the RILEM TC 189-NEC Committee that consists of 26 members representing 12 countries.
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