Wednesday, December 13, 2006

Ground beetles (Family Carabidae) as indicators of change in forest floor processes due to long-term precipitation alteration

Bryan S. Marbert, and Ray S. Williams, Appalachian State University, Biology, PO Box 32027, 572 Rivers Street, Department of Biology, Boone, NC

Global climate change is predicted to alter precipitation patterns in temperate forest ecosystems. Our research used ground beetles (Family Carabidae) as indicators of environmental change caused by precipitation alterations to an intact hardwood forest. In May 2005 we established 10 8 X 8 m plots in each dry, control, and wet treatment plots previously established at the Oak Ridge National Laboratory,TN, Throughfall Displacement Experiment (TDE). Pitfall traps were used to collect beetles during spring, summer, and fall of 2005. Total mean carabid abundance was significantly less in the dry compared to wet treatment (p=0.0311). Coupled with this observation, mean Oi layer litter mass was significantly greater (p=0.0235) in the dry treatment (467.11 g/m2) than in the control (379.56 g/m2). The chemistry of litter was also affected by treatment where tannic acid equivalents (p=0.0193) and C:N ratio (p=0.0215) were significantly greater in the dry treatment Oi layer. Litter moisture generally did not differ between the three treatments. Our research indicates that if precipitation patterns change in temperate ecosystems, forest floor processes along with their fauna may be altered, potentially affecting carbon storage in the forest floor.

Species 1: Coleoptera Carabidae (ground beetle)