583-1 Land Use Effects on Microbial Community Dynamics in the Everglades Agricultural Area, Florida.

Monday, 6 October 2008
George R. Brown Convention Center, Exhibit Hall E
Rongzhong Ye1, Alan Wright2, K. R. Reddy3, Yu Wang1 and Kanika Inglett1, (1)PO Box 110510, University of Florida, Gainesville, FL
(2)University of Florida, Belle Glade, FL
(3)Wetland Biogeochemistry Laboratory, University of Florida, Gainesville, FL
Soil subsidence has become a critical problem since the onset of drainage of the organic soils in the Everglades Agriculture Area (EAA), which may impair current land uses in the future. The objectives of this study were to characterize soil microbial community-level physiology profiles, extracellular enzymatic activities, microbial biomass, and nutrient pools for four land uses: sugarcane, turfgrass, pasture, and forest. Long-term cultivation and management significantly altered the distribution and cycling of nutrients and microbial community composition and activity in the EAA, especially for sugarcane and turf fields. The least managed fields under pasture had the lowest microbial biomass and P levels. Turf and forest had higher microbial metabolic diversity than pasture or the most intensively-managed sugarcane fields. Land use changes from sugarcane cropping to turf increased microbial activity and organic matter decomposition rates, indicating that changes from agricultural to urban land uses may further contribute to soil subsidence.