Agricultural mosaics` novel ecosystems in the rolling pampas of Argentina

GHERSA CLAUDIO M.; POGGIO SANTIAGO L.; MOLINA GONZALO A. R.; LE FEÓN VIOLETTE; WEYLAND FEDERICO

Portland, Oregon

Congreso; 97th Annual Meeting, Ecological Society of America; 2012

Ecological Society of America

The Pampas plains, originally covered by grasslands communities organized by small topographic differences, and rainfall and temperature gradients, were developed into an agricultural mosaic.  Human activities altered the natural heterogeneity and introduced new organisms assembling novel ecosystems. Our aim is to highlight the contribution of anthropic elements in farmland mosaics to retain biodiversity and its associated ecological functions and services.  We describe the different elements (land use, cropping activities, field size, road and fence networks, rural homesteads and woodlots).   We also analyze the proportion of the area occupied by each element type and its contribution to the overall diversity. We performed physiographic and physiognomic studies together with plant surveys over the different landscapes in the Rolling Pampas and during a series of years. We also used surveys and trapping to study bird, arthropods and small rodents.  Species richness and abundance were determined for the different taxa and landscape elements. Fauna was also classified according to functional characteristics. Elements´ area was determined, and they were further classified in a hierarchy according to area and species contribution to the agricultural mosaic biodiversity.