Tree islands of the Florida everglades? Long-term stability and response to hydrologic change

Tree islands are important centers of biodiversity in the Florida Everglades; they have two to three times the plant and animal diversity of the surrounding wetlands. This high diversity is due primarily to their higher elevation relative to the adjacent wetlands (fig. 1). In the natural Everglades system, water levels fluctuated seasonally with rainfall, and tree islands were the only sites that escaped flooding during the wet season. These seasonally dry sites provided refugia and nesting sites for animals and allowed tree and shrub communities to flourish.