SS3.06 Large Scale Change in Prominent Ecosystems
Date: Wednesday, June 12, 2002
Time: 10:15:00 AM
Location: Lecture Theatre
 
GaiserEE, Florida International University/Southeast Environmental Research Center, Miami, USA, gaisere@fiu.edu
Childers, D, L, Florida International University/Southeast Environmental Research Center, Miami, USA, childers@fiu.edu
Jones, R, D, Florida International University/Southeast Environmental Research Center, Miami, USA, serc@fiu.edu
 
EFFECTS OF HYDROLOGIC AND NUTRIENT ALTERATIONS ON PERIPHYTON BIOMASS AND COMPOSITION ACROSS THE EVERGLADES LANDSCAPE (FLORIDA, USA)
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The Everglades of South Florida, one of the largest wetlands in the world, is threatened by a century of large-scale perturbations in water flow and nutrient inputs. Mat-forming periphyton aggregations containing hundreds of species of algae, fungi and bacteria dominate primary production, support a diverse food web, and control soil formation and biogeochemical cycling in these marshes. To determine landscape patterns of periphyton structure and function in the Everglades, we examined biomass, species composition, nutrient content and productivity at 120 random sites and 63 sites distributed along transects in 5 major Everglades basins. We coordinated our survey with other investigators who collected biogeochemical, soil, plant, and consumer data from the same sites. Variation in most periphyton attributes could be explained in part by two factors: flooding duration (hydroperiod) and nutrient availability. A surprising negative relationship between periphyton biomass and phosphorus availability was detected in all basins. We developed basin-specific models to predict hydroperiod and phosphorus availability from periphyton community attributes that can be used to gauge the success of pending large-scale water quantity and quality restoration efforts in the Everglades.