Wetlands come in all shapes and sizes.
They occur in every state, from the coastal marshes of Alaska to the mangrove forests of Florida. Some are dry on the surface most of the year and others remain saturated or even inundated. There are two main categories of wetlands - coastal and inland. Coastal wetlands occur near the ocean and are closely linked with estuaries, where sea water mixes with fresh water. Inland wetlands occur everywhere from plains to mountain tops.