Keystone arthropods as webmasters in desert ecosystems.

Abstract

Despite the paucity of literature on patch generation in desert landscapes, there are several studies that provide evidence for the keystone role of ants and termites as agents which affect landscape heterogeneity at the different spatial and temporal scales reviewed here. How termites and ants control the spatial and temporal distribution of critical resources such as water and nutrients, thereby affecting essential ecosystem process such as productivity and nutrient cycling, are described. The data summarized are predominantly for the Chihuahuan Desert in North America and a few desert areas in Australia. Termites and ants affect virtually all the ecosystem processes, i.e. infiltration, runoff, sediment yield, nutrient cycling and plant production. Not only do these arthropods affect processes on the ecological time-scale, they also affect processes on the geological time-scale through the movement of soil materials to the surface where they are subjected to physical and biological weathering.