PARENT SESSION
Oral Session #46: Disturbance Ecology.
Presiding: M. Slocum
Tuesday, August 6. 1:00 PM to 4:45 PM. Grand Ballroom East, Radisson.
Development of ecological indicator guilds for land management.
Krzysik, Anthony*,1, Kovacic, David2, Wallace, Michael2, Zak, John3, Graham, John4, Freeman, Carl5, Emlen, John6, Duda, Jeff6, 1 Embry-Riddle Aeronautical University, Prescott, AZ2 University of Illinois, Champaign-Urbana, IL3 Texas Tech University, Lubbock, TX4 Berry College, Mount Berry, GA5 Wayne State University, Detroit, MI6 U.S. Geological Survey - BRD, Seattle, WA
ABSTRACT- Ten Ecological Indicator Systems (EISs) are being researched and developed for the purpose of assessing and monitoring ecological conditions and trends resulting from landscape scale mechanized infantry military training activities. The guild approach motivates the classification of EISs into groups of similar responses to ecological conditions/trends for guiding multiuse land management options. Nine research sites representing a gradient of vegetation and soil disturbance were selected in longleaf pine sand hills physiography at Fort Benning, Georgia. Discriminant analysis, nonmetric multidimensional scaling, canonical correspondence analysis, and other analytical tools were used to quantify, characterize, and associate ecological indicators. The following EISs are discussed analytically in relation to landscape disturbance gradients: habitat physiognomy and floristics, microbial functional diversity, nitrogen flux/leakage, ant communities, and plant physiological responses and developmental instability. Soil compaction was the primary habitat parameter that separated Low from Medium disturbance sites. High disturbance sites differed from Medium sites by possessing: lower tree canopy cover and basal area, more bare ground and less litter, shallower soils, less diverse woody ground cover, lower microbial activity, greater nutrient leakage, and lower soil organics and nitrate. Developmental instability and plant transpiration rates increased with habitat disturbance, while net photosynthesis declined. Other quantitative ecological differences among site disturbance gradients included fungal and bacterial functional diversity and the structure of ant communities.
KEY WORDS: ecological indicators, military training disturbance, landscape disturbance gradients, multivariate community analysis