Inhaltszusammenfassung

A tremendous number of indices exists to calculate landscape beta diversity or species heterogeneity between two or more samples. Here, we propose to calculate a set of related indices to differentiate between several effects that lead to heterogeneity or homogenization. Turnover and pairwise similarity indices do not differentiate between heterogeneity along rising distance or patchiness of species sorting in the landscape. Calculating similarity of species in relation to the complete datase...A tremendous number of indices exists to calculate landscape beta diversity or species heterogeneity between two or more samples. Here, we propose to calculate a set of related indices to differentiate between several effects that lead to heterogeneity or homogenization. Turnover and pairwise similarity indices do not differentiate between heterogeneity along rising distance or patchiness of species sorting in the landscape. Calculating similarity of species in relation to the complete dataset, the determination of the effect of nestedness and of distance decay characterize the degree of homogenization of species composition in the landscape. Additional trait analyses uncover i.a. eutrophication effects on species sorting processes. In an example the equivocal use of some beta diversity indices is demonstrated. The need for twofold conservation measures in the agricultural area studied is highlighted.» weiterlesen» einklappen

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