The role of the soil seed bank in freshwater marl prairie plant community restoration: Big Cypress Basin, Florida, USA

Restoration of disrupted or degraded ecological processes can lead to reestablishment of the biotic components of an ecosystem. In some cases, however, even with the return of natural ecological processes (e.g. disturbance regime), propagule limitation leads to depauperate plant communities. Potential changes in water management in southwest Florida, along with conservation plans to increase prescribed burning, present an opportunity to restore freshwater marl prairie in the Big Cypress Basin, FL, USA. To assess the potential contribution of the seed bank to restoration of the wet prairie plant community, we assayed the soil seed bank of two degraded depressional wetlands within the wet prairie matrix. Although the seed bank contained many species characteristic of the ecosystem type (Bacopa caroliniana, Proserpinaca palustris, Mikania scandens, Eleocharis spp.), key components of species composition, typically those that rely primarily on vegetative propagation, were not present in the seed bank (e.g. Cladium jamaicense, Rhynchospora spp.). Therefore, natural recolonization following restoration of hydrology and fire regime may be insufficient to restore critical species to these sites. Further, presence of invasive species in the seed bank (Typha domingensis) may complicate establishment of desirable native species. These data indicate that freshwater marl prairie sites in this region may require active revegetation to restore the full complement of critical species. Our results support conclusions from other studies that have found the contribution of the seed bank to plant community recolonization to be limited for degraded wetlands in this region.