WATER USE IN MANGROVE COMMUNITIES OF BISCAYNE NATIONAL PARK, FL
G.J. Telesnicki, M.S. Ross, S. Oberbauer, J.F. Meeder, and P.L. Ruiz
Southeast Environmental Research Program, Florida International University, Miami, Fl 33199
Water use for Rhizophora mangle
& Laguncularia racemosa
were estimated for scrub and paralic mangrove communities along a coastal gradient in Biscayne National Park, FL. Flow measurements were based on a Stem Heat Balance model. In this method, radial and vertical heat conduction are partitioned and separated from connvective sap transport by measuring differential temperature over short sections of live stem trunk. Rainfall, barometric pressure, relative humidity, solar radiation, temperature, and wind speed data were collected to assess the relationships between climatic variables and stem flow. Predawn moisture stress and stomatal conductance were also measured on the same or adjacent trees through a diurnal cycle. Sap flow and stomatal conductance showed typical diurnal flow patterns. Individual sap transport rates were expressed on a leaf area basis, which allowed us to scale up observed species and site differences among individuals to the community and ecosystem levels.