Spatial pattern formation of coastal vegetation in response to external gradients and positive feedbacks affecting soil porewater salinity: a model study
Authored by Donald L DeAngelis, Jiang Jiang, III Thomas J Smith, Su Yean Teh, Hock-Lye Koh
Date Published: 2012
DOI: 10.1007/s10980-011-9689-9
Sponsors:
United States Geological Survey (USGS)
Platforms:
No platforms listed
Model Documentation:
ODD
Mathematical description
Model Code URLs:
Model code not found
Abstract
Coastal vegetation of South Florida typically comprises
salinity-tolerant mangroves bordering salinity-intolerant hardwood
hammocks and fresh water marshes. Two primary ecological factors appear
to influence the maintenance of mangrove/hammock ecotones against
changes that might occur due to disturbances. One of these is a gradient
in one or more environmental factors. The other is the action of
positive feedback mechanisms, in which each vegetation community
influences its local environment to favor itself, reinforcing the
boundary between communities. The relative contributions of these two
factors, however, can be hard to discern. A spatially explicit
individual-based model of vegetation, coupled with a model of soil
hydrology and salinity dynamics is presented here to simulate
mangrove/hammock ecotones in the coastal margin habitats of South
Florida. The model simulation results indicate that an environmental
gradient of salinity, caused by tidal flux, is the key factor separating
vegetation communities, while positive feedback involving the different
interaction of each vegetation type with the vadose zone salinity
increases the sharpness of boundaries, and maintains the ecological
resilience of mangrove/hammock ecotones against small disturbances.
Investigation of effects of precipitation on positive feedback indicates
that the dry season, with its low precipitation, is the period of
strongest positive feedback.
Tags
Competition
Dynamics
Australia
Habitats
Simulation-model
Florida
Treeline ecotones
Mangrove forests
Inland mangroves
Everglades