The 295,000 hectare wetlands of the Big Cypress Natural Preserve and the adjacent Fakahatchee Strand State Preserve in southwest Florida have been described by the US Forest Service (1996) as a flat, gently sloping limestone plain. During the rainy season (June through September) water flows slowly southward over this plain into the mangrove swamps bordering the Gulf of Mexico. This flow rate, however, is slower than what occurs in the sheet flow that originates from Lake Okechobee and flows southwestward through the (mostly) Cladium-dominated (gramminoid) prairies. During low water periods there may be no discernible flow through the cypress wetlands. In places, the flow of water has cut channels into the limestone, allowing deep organic soils to develop. These channels, or drainage sloughs, are occupied by tall, dense, elongated swamp forests that stand out on the horizon in contrast to the open terrain that borders them. The local term for this type of elongated swamp is "strand."

Another type of deepwater, cypress-dominated swamp, is called a "dome". Cypress domes are generally small in size, usually 1 to 10 hectares and consistof poorly-drained to permanently wet depressions that are dominated by pondcypress. They are called "domes" because, when viewed from the side, the larger trees in the middle and the smaller trees toward the edges present a vaulted profile. This domed appearance has been attributed variously to a deeper deposit of peat in the middle, fire that is more frequent around the edges, or a gradual increase in water level that causes the dome to "grow" from the center outward. But a definite reason for this profile has not been determined yet, nor do all domes display the characteristic shape (Mitsch and Gosselink, 1993).

During periods of low water levels, water is impounded in numerous ponds. Elevation ranges from 3.6-12 m above mean sea level in the northern part of Big Cypress to sea level where it grades into mangrove swamps.

The climate of southern Florida is moist and mild; it is frost-free nearly all year. Mean annual precipitation is around 1,500 mm, 80 percent of which falls from May to October, creating distinct wet and dry seasons. Precipitation received in 1 year has ranged from 760 to 2,540 mm. Occasionally, drought in summer (normally the wet season) can result in complete cypress defoliation, which otherwise would not occur until fall.