PARENT SESSION
Oral Session #46: Disturbance Ecology.
Presiding: M. Slocum
Tuesday, August 6. 1:00 PM to 4:45 PM. Grand Ballroom East, Radisson.
Stream indicators of ecological impacts from military training at Fort Benning, Georgia.
MULHOLLAND, PATRICK*,1, HOUSER, JEFFREY1, FEMINELLA, JACK2, MALONEY, KELLY2, 1 Oak Ridge National Laboratory, Oak Ridge, TN2 Auburn University, Auburn, AL
ABSTRACT- Military bases are often islands of relatively rich biological habitat within agriculture-dominated regional landscapes. Military training activities, particularly intensive maneuvers involving large tracked vehicles, can result in degradation of habitat via vegetation removal, erosion and deterioration of water quality in adjacent aquatic ecosystems. As part of the U.S. Department of Defense's Strategic Environmental Research and Development Program (SERDP), we are evaluating several ecological indicators that can be used to determine when training activities result in unacceptable ecosystem degradation. We are measuring a number of physical, chemical, and biological characteristics in 1st- and 2nd-order streams draining catchments spanning a wide range in disturbance severity at Fort Benning in the Sand Hills (Coastal Plain) region of western Georgia. Our results indicate that suspended sediment concentrations, particularly during storms, diurnal dissolved oxygen profiles, streambed organic matter content and sediment movement, and abundance of chironomid midges Rheosmittia sp. and Lopescladius sp. appear to be good indicators of disturbance within the catchment. Somewhat surprisingly, stream water nutrient concentrations and traditional stream macroinvertebrate community metrics, such as total invertebrate and EPT richness, were not particularly useful indicators of disturbance. Our results suggest that the primary impacts on stream ecosystems from military training at Fort Benning are upland erosion and increased sediment loading of streams that reduce the quality of habitat for benthic biota.
KEY WORDS: disturbance, stream, sediment