Ground-dwelling spiders in agroecosystems of the Dry Chaco: A rapid assessment of community shifts in response to land use changes

Abstract

Deforestation and land-cover changes have transformed the Argentinian Dry Chaco into a mosaic dominated by crops and ranch fields. Although land-use activities are seen as one of the major driving forces of biodiversity loss, the specific impacts in this ecoregion are poorly understood. In this study, we analyse the effects of land-uses and management on ground-dwelling spiders in agroecosystems of the Dry Chaco, in the North of Argentina. We identified four land-use classes: secondary forests, pastures, orchards, and crops. Additionally, 15 environmental variables were recorded within these land-use classes. Management, tree cover and species richness of trees, shrubs and herbs were the most important variables determining spider community composition. Three families, lycosids (Lycosidae), thomisids (Thomisidae), and zodariids (Zodariidae), were associated as taxonomic indicators as well as functional indicators of the different groups of land-uses; thus suggesting that functional traits of ground-dwelling spiders reflect habitat changes within the agricultural landscape they inhabit.