Richard Roberts
Wednesday, October 15, 2008 - 4:00-4:30
The Northwest Fork of the Loxahatchee River is located in southeastern Florida. In May 1985 a portion of this blackwater river/floodplain swamp consisting of tropical and temperate vegetation was designated as Florida’s first National Wild and Scenic River. Unfortunately, in less then 60 years the natural hydrological system of the river’s watershed has been altered by drainage activities associated with agriculture, urbanization and the Jupiter Inlet being opened permanently to the Atlantic Ocean. These multiple impacts have brought about unwanted changes in the balance of freshwater and saltwater interface resulting in the encroachment of saltwater-tolerant mangroves into freshwater forested communities in the tidal reach and invasion and displacement of some plant species in the riverine reach. Since the early 1970s remedial actions have been taken to improve management of water flows and in 2003 a joint agency effort initiated a ―practical restoration plan‖. Our 2003 Loxahatchee River Floodplain Study investigated 10 vegetational transects, including earlier research. The study consisted of 138 vegetational plots with 26 canopy species, 52 shrub species and 73 groundcover species, along with four environmental variables (river mile, elevation, soil type and forest type). Within the three riparian reaches, fifteen forest community types were identified. The major vegetative types were identified as swamp, bottomland hardwoods, hydric and mesic hammocks and uplands. Stage and flow relationship was also established for several of these forest types. Other factors that contributed to the determination of the plant community structure included logging, exotic vegetation, hummocks and upland plant invasion.
Keywords: CYPRESS, MANGROVE, SALTWATER INTRUSION, LOXAHATCHEE RIVER