PARENT SESSION
Organized Oral Session 46: Ecological indicators at multiple scales
Organizer(s): F Müller and E Hyatt
Thursday, August 11, 8:00 AM - 11:30 AM, Meeting Room 516 C, Level 5, Palais des congrès de Montréal
Ecological indicators from the microbial to the landscape level.
Dale, Virginia*,1, Druckenbrod, Daniel1, Feminella, Jack2, Maloney, Kelly2, Mulholland, Patrick1, Peacock, Aaron3, 1 Environmental Sciences Division, Oak Ridge, TN, USA2 Department of Biological Sciences, Auburn, AL, USA3 Center for Environmental Biotechnology, Knoxville, TN, USA
ABSTRACT- Characterizing how resource use and management activities affect ecological conditions is necessary to document and understand ecological changes. Resource managers on military installations have the delicate task of balancing the need to train soldiers effectively with the need to maintain ecological integrity. Ecological indicators can play an important role in the management process by providing feedback on the impacts that training has on environmental characteristics, including soil microbes, stream invertebrates, stream chemistry, terrestrial vegetation, and landscape patterns. These indicators vary in their responses across a range of spatial and temporal scales. We established field observations and experiments in longleaf pine (Pinus palustris) systems with different types of military training at Fort Benning in south central Georgia in the southeastern United States. Our research narrowed potential indicators at the plot level to include measures of the microbial soil community and understory vegetation cover, richness and life forms. At the catchment level, indicators include stream storm hydrograph recession constants, suspended sediment concentrations (total and inorganic) during baseflow and storms, baseflow concentrations of PO4 and DOC, stormflow concentrations of NO3 and PO4, benthic macroinvertebrates, and fish. These stream-based hydrological, chemical and biological indicators were strongly related to the proportion of bare ground and upaved road cover in the catchment. At the broad scale of the entire installation, final indicators include percent cover, total edge, number of patches, mean patch area, patch area range, coefficient of variation of patch area, perimeter/area ratio, Euclidean nearest neighbor distance, shape range, and clumpiness. Together, these indicators provide a means for resource managers to monitor changes in ecological conditions and to understand impacts of land use practices at Fort Benning. Our approach of using field studies and experiments to examine a hierarchy of indicators should be applicable to resource management in other ecological systems as well.
Key words: indicator, scale, hierarchy