Salt marshes are the coastal wetlands being inundated and drained by every salt water carried by the tides. You can find them out marshy since the soil might possibly be made up of a deep mud and a peat. Peat is made from a decomposing plant matter which is often more than a few feet thick. Peat appears to be waterlogged, root-filled, and even extremely spongy.
For the reason that salt marshes are often immersed by the tides and hold a large amount of decomposing plant materials, oxygen levels in a peat can be very low—a condition generally known as hypoxia. Hypoxia is actually due to the development of bacteria which emit the sulfurous rotten-egg odor which is often related to marshes and the mud flats.
These areas manifest throughout the world, particularly in mid to high latitudes. Flourishing on protected coasts, they are a typical habitat within estuaries. In the U.S., salt marshes exists on just about every coast. Around 50% the nation’s salt marshes are situated along the Gulf Coast.