11-3 Intertidal Zones Located along the shoreline of the world. It alternates twice each day between periods of exposure at low tide and periods of submersion at high tide.

Organisms Organisms which live here must be able to live out of water as well as submerged in water. These organisms must be able to also withstand the pounding of the tides so they attach themselves to rocks and things and also burrow into the sand.

Intertidal Zone Organisms

Since these zones are located where the land meets the water, they are surrounded by a lot of wetlands. Two main wetlands are salt marshes and mangrove swamps.

Salt Marshes Flat, muddy wetlands that surround estuaries, bays and lagoons. Influenced by tides. Found along coastlines. 1 important factor is in supporting, feeding and resting of migratory birds. Another important factor is the plants which grow here die and wash into the surrounding estuary to help feed the marine animals that breed there. Salt marshes form by sediments that are deposited by streams which flow into an estuary. These sediments build up over time and form a delta. The sediments, in time, sink under water due to their own weight. This process is called subsidence. This gives deltas their stability.

Salt Marshes

Mangrove Swamps The roots of the trees are adapted to low oxygen because they emerge from the water to obtain oxygen from the air. Homes to migratory birds, shellfish and various types of grasses called spartina grass. Mangroves are being destroyed by coastal building, waste dumping, and development of culture ponds for raising fish and shrimp commercially. A type of coastal wetland that occurs only in warm climates. The largest mangrove forest is in southeast Asia. Frost kills plants here These areas can only freeze once or twice a year The mangrove tree is the most dominant plant Water has very little dissolved oxygen

Mangrove Swamps