SUBSTRATE: Dominantly sandy with beds of clay, phosphatic
mudstone, and peat; usually underlain by limestone.
TOPOGRAPHY/HYDROLOGY: Most Florida lakes formed by dissolution
of limestone bedrock, subsequent groundwater flow into subterranean
caverns, and collapse of surface layers. 7800 lakes greater than
1 acre; most are small, shallow, and in central, sandy ridge part
of state; Okeechobee produced by an uplifted sea-floor depression,
is by far the largest.
VEGETATION/ALGAE: Density and diversity of microalgal species
dependant on trophic level; aquatic plants, macroalgae, mosses,
and floating flowering plants particularly important in Florida's
numerous shallow lakes.
FAUNA: Molluscs, crustaceans, larval and adult insects common;
about 40 species of native fishes.
PROCESSES/DYNAMICS/ABIOTIC FACTORS: Trophic (nutrient) status
varies; most lakes are poorly to moderately supplied with nitrogen
and phosphorus nutrients and have low to medium densities of microalgae
and aquatic plants.
HUMAN IMPACTS: Discharge of nutrients and other pollutants
from human activities; siltation from forest clearing; exotic plant
species, such as water hyacinth and hydrilla, clog waterbodies and
change their chemical composition; native fish experience competition
from 21 established exotic fish species.
ANIMALS AND PLANTS NATIVE TO ECOSYSTEM: List of selectable
animals and plants
native to the Lakes ecosystem, with detailed descriptions and pictures