The vegetation of the Everglades and in particular the marl prairies is
linked to both microtopography and the hydrology of the land. As can
be seen from the figure at right (adapted from Werner 1975), the Muhlenbergia
filipes and the sparsely vegetative Cladium jamaicense prairies are
located at different elevations in the Everglades. The muhly grass prairies tend
to exist at higher elevation than the thin sawgrass areas which in turn exist
at higher elevations than thick stands of sawgrass.
Although there is a clean ecotone between the three ecotypes in the figure, this ecotone is extremely dynamic. The elevation where Muhlenbergia grass dominated prairie will exist shifts according to hydrology. If there is a series of dry years, the Muhlenbergia grass/thin stands of Cladium ecotone may shift down in elevation. If there is a series of wet years, this ecotone will shift up in elevation and if this shift is large enough it may eventually exclude Muhlenbergia filipes from the area diagrammed. These same logical arguments can also be applied to the thin Cladium/thick Cladium ecotone as well.