Impact of different land management on soil spiders (Arachnida: Araneae) in two Amazonian areas of Brazil and Colombia.

The global demand for different land-use practice commodities in the Amazonia is growing, and this region is increasingly affected by the impacts of land management. The aim of this study was to evaluate the influence of land-use intensification on soil spider assemblages from six different land-use systems in Colombia and Brazil. The systems were fallows after crops and pastures, forest, crops, pastures and plantations. Spider species richness and density decreased with increasing farming management intensity. A principal component analysis (PCA) showed forests and fallows were separated from systems with stronger anthropogenic soil disturbance. The relationships of ten spider guilds differed significantly between land-uses, suggesting that they can be a reliable parameter for studies of ecological indicators. [ABSTRACT FROM AUTHOR]