Influence of red imported fire ants on greenhouse gas emissions from a piedmont plateau pasture

Researchers have previously attempted to relate the influences of many ant species to the nitrogen (N) and carbon (C) cycles. However, the gaseous phases of these cycles have been neglected. A field study was conducted near Auburn University (32degrees52'N, 85degrees30'W) in a bermudagrass [Cynedon dactylon (L.) Pers] pasture to determine the influence of the red imported fire ant [Solenopsis invicta (L.) Buren] on soil emission of three greenhouse gases from April 1999 to April 2000. A completely random design was used with three replications. Treatments consisted of ant influenced soil (mounds) and-non-ant influenced control soil. Surface emission rates of N2O-N, CH4-C, and CO2-C were measured bi-weekly using. a closed chamber technique.. Soil collection to a depth of 100 cm was used to determine soil moisture, pH, and status of soil N and C. While the red imported fire ant significantly influenced greenhouse gas fluxes from mound soil, it was concluded that for. a bermudagrass pasture in Alabama, the increase of annual emissions of N2O-N, CH4-C, and CO2-C was only 6.95 g N ha(-1), 0.16 g C ha(-1), 0.92 kg C ha(-1), respectively. It is speculated that regional and global budgets of these greenhouse gases may be underestimated when the influence of soil macro-organisms, such as ants, are not taken into account. However, this underestimation may only be slight.