Submitted to: American Society of Agronomy
Publication Type: Abstract Only
Publication Acceptance Date: September 1, 1995
Publication Date: N/A
Technical Abstract: The activity of soil fauna is frequently cited as a factor contributing to the spatial variability of arid rangeland soils in the southwestern United States. However, few studies have correlated differences in soil physical properties with the activity of specific soil organisms. In order to quantify the contribution of ant activity to spatial variability in surface emacroporosity, infiltration rates under ponding and under tension at the center and margins of harvester ant (Pogonomyrmex rugosus) nests were compared with rates in adjacent unvegetated control sites. Both saturated hydraulic conductivity and the difference between saturated and unsaturated conductivity were highest at the nest centers. These results illustrate the role of ants in the creation of macropores capable of conducting water under conditions of overland flow. The results will be discussed with respect to patterns and densities of ant nests in the Chihuahuan Desert.