Swamp is a wetland where trees and shrubs grow. Freshwater swamps occur along lakes and slowly flowing rivers and in low-lying areas. Saltwater swamps usually occur along coastlines.
A swamp is flooded with water for at least part of the year. The depth and duration of flooding determine what kinds of plants will grow. Where flooding lasts long, few plants other than trees grow at ground level. Other plants may inhabit hills and ridges that rise above the water, forming tiny islands. Swamps that flood only briefly support a greater variety of plants.
Many swamp trees can tolerate occasional floods. Other swamp trees, such as the baldcypress and the water tupelo, can survive flooding for much of the year. Swamps provide homes for many animals. They include alligators, birds, fish, frogs, mosquitoes, and snakes.
One important type of saltwater swamp is the mangrove swamp, also called mangrove forest or mangal. It is found along tropical seacoasts. The mangrove swamp is named for the mangrove trees that grow there.
Freshwater swamps in the United States include Dismal Swamp in North Carolina and Virginia and Okefenokee Swamp in Georgia. The world’s largest mangrove swamp is the Sundarbans. It covers about 8,000 square miles (20,000 square kilometers) along the coasts of Bangladesh and India.
Swamps protect shorelines from erosion and help preserve water quality. But people have destroyed many swamps to make way for agriculture and construction or to control mosquitoes. People also damage swamps by diverting water or polluting it.
