LAUSR

Coffee is one of the basic commodities of Colombian agricultural production, the country being one of the main producers in the Neotropics. Sun coffee farms are widespread but they are likely to simplify the landscape and degrade biodiversity. In this study, we examined the effect of three land uses associated with coffee production (sun coffee, shaded coffee and natural patches) on species diversity among omnivorous and predatory ants and ground beetles. The study was carried out in Caldono, Cauca in southwestern Colombia; we sampled eight plots of each land use in two collecting sessions. Specimens were captured with pitfall traps and mini-Winkler bags. We sampled each plot for 48 h in each session. Species representativeness for ants was higher than for ground beetles, and species richness of both taxa was higher in natural patches than on coffee farms. Omnivorous ants were more abundant on sun coffee farms, and a higher richness and abundance of omnivorous ground beetles was also observed. Sun coffee farm communities were distant from natural patches, and there were shaded coffee farms in between them. As for indicator species, we found 24 for ants and four for ground beetles. High heterogeneity of landscape and intermingling of farms with other land uses is more important for maintaining biodiversity than considering each land use independently. Although this fauna could be moving across the landscape, small vegetation patches are key to the survival of several species. In general, coffee plantations under the sun favor the generalist species whilst shaded coffee is friendlier with biodiversity, and should be promoted. Finally, we found that severe drought homogenizes tendencies of species richness, and widely favors generalist species.