2,296 research outputs found

    Temporal variation in bird assemblages: how representative is a one-year snapshot?

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    Bird assemblages generally are no longer regarded as stable entities, but rather as fluctuating in response to many factors. Australia’s highly variable climate is likely to result in a high degree of dynamism in its bird assemblages, yet few studies have investigated variation on an inter-annual temporal scale. We compared two year-long samples of the bird assemblages of a series of highly fragmented buloke Allocasuarina luehmannii (Casuarinaceae)woodland remnants in south-eastern Australia, the first sample taken in 1994–1995 and the second in 2001–2002. Bird densities were almost three times higher in the second period than in the first. Mean species richness also was significantly higher. Species richness of each individual site was unrelated between the two years. Minimum species turnover was 63% and was higher, on average, for migratory and nomadic than for sedentary species. Therefore, site-level bird assemblage composition was markedly different between the two survey periods and, on average, the assemblage composition of each site bore greater resemblance to those of other sites in the same year than to that of the same site in the other survey period. Most species changed substantially in their distribution among remnants between the two periods. The change in distribution of most species did not differ significantly from that expected if the species had redistributed at random among the sites. This suggests that although the remnant vegetation of the area is highly fragmented with minimal interpatch connectivity, bird movements among remnants must be relatively frequent. Interannual variability in Australian bird assemblages may be higher than is commonly recognized. In such dynamic systems, we must be cautious when extrapolating from the findings of short-term studies to longer temporal scales, especially in relation to conservation management. A greater understanding of the processes driving distributional patterns is likely to enable better predictions of species’ responses to habitat change

    Science granting councils in Sub-Saharan Africa : final technical report

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    Metrics for measuring distances in configuration spaces

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    In order to characterize molecular structures we introduce configurational fingerprint vectors which are counterparts of quantities used experimentally to identify structures. The Euclidean distance between the configurational fingerprint vectors satisfies the properties of a metric and can therefore safely be used to measure dissimilarities between configurations in the high dimensional configuration space. We show that these metrics correlate well with the RMSD between two configurations if this RMSD is obtained from a global minimization over all translations, rotations and permutations of atomic indices. We introduce a Monte Carlo approach to obtain this global minimum of the RMSD between configurations

    Disaster Resilience Education and Research Roadmap for Europe 2030 : ANDROID Report

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    A disaster resilience education and research roadmap for Europe 2030 has been launched. This roadmap represents an important output of the ANDROID disaster resilience network, bringing together existing literature in the field, as well as the results of various analysis and study projects undertaken by project partners.The roadmap sets out five key challenges and opportunities in moving from 2015 to 2030 and aimed at addressing the challenges of the recently announced Sendai Framework for Disaster Risk Reduction 2015-2030. This roadmap was developed as part of the ANDROID Disaster Resilience Network, led by Professor Richard Haigh of the Global Disaster Resilience Centre (www.hud.ac.uk/gdrc ) at the School of Art, Design and Architecture at the University of Huddersfield, UK. The ANDROID consortium of applied, human, social and natural scientists, supported by international organisations and a stakeholder board, worked together to map the field in disaster resilience education, pool their results and findings, develop interdisciplinary explanations, develop capacity, move forward innovative education agendas, discuss methods, and inform policy development. Further information on ANDROID Disaster Resilience network is available at: http://www.disaster-resilience.netAn ANDROID Disaster Resilience Network ReportANDROI
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