Types of Florida swamps

The most common type of swamp in Florida is the cypress dome. It is called a dome because the tallest trees grow in the middle of the stand and shorter ones grow at the outer edges. This gives a dome appearance to the shape of the tree stand. Studies have shown that the trees in the middle grow faster than those at the edge, but the reason is still a mystery.
 

Cypress dome from the outside.

  

Inside view of a cypress dome. 
            Swamps may be classified as either river swamps or still-water swamps. River swamps have a surface flow of water at least part of the year. They generally have a shorter hydroperiod than still-water swamps with more frequent dry periods in between. River swamps are usually formed from the overflow of rivers or streams. In dry seasons, when water levels drop, these swamps have a mucky, peat-like soil. Swamps with short hydroperiods and flowing water have higher levels of dissolved oxygen and faster rates of organic matter removal. Additionally, water in river swamps is usually clearer and less acidic than in still-water swamps.   Hardwood species are more likely to grow in these wetlands than in still-water swamps. About one-third of the swamps in Florida are classified as river swamps. Most of these are found in Northern Florida.

Still-water swamps have little or no noticeable water flow. These swamps are fed by rainwater or groundwater and have a longer hydroperiod than river swamps. The soil remains saturated most of the time and has layers of clay underneath.  A layer of peat is usually formed on the floor of cypress swamps, the most common type of still-water swamp in Florida.   Leaf and plant litter decomposes more slowly in water-logged swamps. A build up of organic matter can decrease nutrient availability and reduce the availability of oxygen to soil.   Oxygen levels in the water are low so that few species can survive flooding for long periods of time. The trees and plants that do well in these swamps have adapted to flooding and low oxygen levels.   Water in still-water swamps is murkier and darker than in river swamps, partly a result of the slow-moving water and partly because of tannins, substances that seep into the water from plant roots. These substances give the water a characteristic tea-colored look that earned it the name of black water .
 

River swamp in the flood plain of the Suwannee River.

Still water swamps may have long hydroperiods and frequently cypress is the dominate tree.