Efecto de las terrazas sobre la diversidad de artrópodos caminadores en cultivos de soja

Effect of terraces on soil dwelling arthropod diversity in soybean production: The loss of biodiversity in agroecosystems constitutes a main issue in ecological research. Steep backslope terraces, used for soil erosion control, could act as refuges for arthropods in agricultural landscapes. Total and predator arthropod species richness and abundance were surveyed in soybean fields in Entre Rios under a no-till system with and without terraces using pit-fall traps. For the total crop period, total species richness was significantly higher at the margins than in the crop, but not for predator species. Abundance was higher in margins than in crops only when total individuals were considered. Predators were more abundant in margins only at the beginning and the end of the crop cycle, although, in fields with terraces abundance and richness were never higher than in fields without terraces for both total species and predators. Field with terraces did not increase the abundance but increased the species numbers, both total and predators, showing that habitat heterogeneity introduced by terraces favors arthropod diversity at the fi eld scale.