STONE, PETER ALAN.

Floating islands are common natural features in modern Hillsboro
Marsh. Most floating islands: 1) occur as detached,
free-floating batteries (raft-like peaty masses that rise
from substrate), and 2) form in habitats containing abundant
waterlilies. New batteries are quickly colonized by
marsh, and often terrestrial, plants. Differences in
species diversity and early succession occur between two
ecologically different subareas. In one subarea many
batteries succeed quickly to mixed graminoid-arborescent
vegetation. Floating batteries form hydrologically unusual
Everglades habitats and support some locally rare plants.
Battery formation produces local topographic elevations and
depressions. Apparent size-successional vegetational and
landform continuumns seem to link batteries with small extant
tree-islands. Radiometric evidence suggests presence of
batteries in peat profiles of two tree-islands. Everglades
floating islands most resemble others reported in southeastern
United States and appear dissimilar morphologically and
in mode of origin to those reported from elsewhere worldwide.