Mangrove Morphological Change Across an Environmental Gradients: Implications for Competitive Ability in a Changing Climate

In Florida, mangroves have responded to climate change by slowly migrating
northward into traditional salt marsh habitat. However, little is understood about the
relationships among mangrove growth form plasticity and environmental conditions. In
addition, the effects of the mangrove northward expansion on pre-existing salt marsh
communities are unknown, especially any influences of differences in tree morphology.
The size, canopy structure, and root structure of the three mangrove species Rhizophora
mangle, Avicennia germinans, and Laguncularia racemosa were measured at six sites
along the east coast of Florida. Structural equation modeling was used to evaluate the
multivariate relationships between environmental and biotic variables. Mangrove growth
form varied widely with environmental variables. The results of this study suggest that R.
mangle expansion into salt marsh may rely on interactions with salt marsh and shading as
well as on climatic variables, which has implications for future mangrove expansion
northward in Florida.