ABSTRACT
Background ....................................................................................................................................629 Nitrogen Loading from the Everglades to Downstream Coastal Waters......................................630 Nitrogen Enrichment Initiates Biotic Phase Shifts in Florida Bay...............................................633 Nutrient Enrichment and Decline of Coral Reefs in the Florida Keys ........................................639 Summary and Conclusions ............................................................................................................644 Acknowledgments ..........................................................................................................................645 References ......................................................................................................................................645
This chapter describes how human alteration of the Everglades watersheds in South Florida have increased nutrient loads to “downstream” seagrass communities in Florida Bay and coral reefs in the Florida Keys. We also describe how these hydrological and biogeochemical modifications have resulted in nutrient enrichment of coastal waters, initiating harmful algal blooms and seagrass dieoff in Florida Bay and loss of coral communities on the Florida reef tract. Historically, nutrient concentrations were very low in the upland freshwater ecosystems in South Florida and controlled largely by nutrient concentrations in rainfall. Sheetflow drained southward through the Everglades marsh system and fringing mangroves where natural biogeochemical nutrient cycling prevented
