Ground cover recovery patterns and life-history traits: implications for restoration obstacles and opportunities in a species-rich savanna
* 1We identified species with low re-colonization potential, which could be used as indicators of recovery of species-rich pine savannas, by comparing the ground-cover flora of a 64-year-old slash pine plantation (recovery site) with that of a nearby natural longleaf pine savanna (reference site). We also determined life-history traits that were useful predictors of recolonization potential. * 2The high floristic overlap in species between reference and recovery sites and similar species richness at scales ≥ 10 m2 suggests that substantial vegetation recovery occurred over the 65-year period. However, for areas < 10 m2 the lower species packing in the recovery sites indicates that coexistence of a high number of species at small scales is dependent on local dispersal and establishment, and may take much longer to achieve. * 3The absence, or near absence, of some species from the recovery site, even after 65 years, suggests that some species may be particularly vulnerable to disturbance and may re-establish infrequently, if ever. Several dispersal distance-restricted species were identified that require active reintroduction. While no particular guild of species was a strong indicator of recovery in this study, we identified a group of species that assess the absence of or the degree of recovery from, prior soil disturbance. * 4Local dispersal appears to be an important factor structuring species richness patterns in pine savannas. Limitations of dispersal distance in some species, particularly those with gravity and ant-dispersal mechanisms, represent an obstacle to passive restoration that can only be overcome either by introduction of propagules in the restoration process or by allowing for longer periods of recruitment. * 5This study demonstrates a method for identifying a suite of species that may be unsuccessful at recolonization. The method would be applicable to numerous degraded ecosystems, particularly similar species-rich savannas, grasslands and forests.