Impact of the red imported fire ant (Solenopsis invicta) on soil arthropods of a cotton agroecosystem

The Red Imported Fire Ant (Solenopsis invicta) is a common arthropod in most, if not all, disturbed soils of the southern United States.  Introduced from South America in the late 1930’s, the Red Imported Fire Ant (RIFA) now plays a significant role in shaping arthropod communities.  Aside from their well-understood role in aboveground foodwebs, there is also a limited body of evidence suggesting that the RIFA may have a significant impact on soil fauna.  This study examines soil arthropod community dynamics over the course of one growing season at the Horseshoe Bend Agroecosystem in Athens, GA in both the presence and absence of fire ants.  The overarching theme for research at this site deals with the sequestration of soil organic carbon under different agricultural management strategies.  Given the important role of soil arthropods in the processing of soil organic matter, this study may have implications at both community and ecosystem levels.  Results from analysis at the whole-community level (abundance, richness and diversity) indicate that the exclusion of fire ants can increase soil arthropod diversity.  At the morpho-species level (indicator species analysis) there appear to be two collembola and one mite species significantly associated with fire ant exclusion.