Dynamic spatial simulation modeling of coastal wetland habitat succession

Abstract To adequately model many ecological systems and management problems, spatial dynamics need to be treated explicitly. A dynamic spatial simulation model composed of interacting cells was designed to project habitat changes as a function of marsh type, hydrology, subsidence, and sediment transport for a generalized coastal wetland area. The model with nine interacting cells was developed to test mathematical formulations and computer algorithms, and to help explain model structure and behavior. Each cell in the model is classified and assigned a habitat parameter ‘signature’ corresponding to a multidimensional niche space. Large-scale habitat changes (‘succession’) occur in the model when water and material fluxes between cells produce storages corresponding to the signature of a new habitat. After some time lag to reflect successional changes, the cell parameters are changed to reflect the new habitat signature. In this manner the model can be used to project the impact of natural and man-made changes (i.e., levees, canals) to the system on the spatial distribution and productivity of the various habitats.