Soils are dominantly sandy but significant expanses of clayey deposits exist. The ecosystems associated with this district include pine flatwoods, dunes, and salt marshes. It originated as a series of barrier islands and lagoons and is presently consists of broad expanses of flatwoods with prairies, ridges, and a variety of coastal features. Soils are sandy with significant areas of peat deposits. The ecosystems associated with this district include pine flatwoods, prairies, cypress ponds, dunes, and mangroves.
Parent material is largely limestone rock with a sand, marl, and organic material covering.
The ecosystems associated with this district include marshes, dwarf cypress, prairies, rocklands, and mangroves. Soils are sand, clay, limestone, and organic deposits. The ecosystems associated with this district include pine flatwoods, prairies, cypress ponds, mangroves, and dunes. It is a sandhill karst terrain with many solution basins. The permeable sands and rapid internal drainage of this region make it the principal recharge area of the Florida aquifer.