Estuary: An estuary is a partly enclosed body of water formed where freshwater from rivers and streams flows into the ocean, mixing with the salty sea water. Estuaries and the lands surrounding them are places of change from land to sea, and from fresh to salt water. Although influenced by the tides, estuaries are protected from the full force of ocean waves, winds, and storms by the reefs, barrier islands, or fingers of land, mud, or sand.

Wetland: Land soaked in water most of the time. The soil is soaked in water, it's called "hydric soil." Plants that need a lot of water grow there.

Swamp-Low land that is seasonally flooded; has more woody plants such as cypress trees or oaks than a marsh and better drainage than a bog. A wetland characterized by trees and shrubs

Saltwater Marsh-A saltwater marsh, found on ocean coastlines, is has mostly tough grasses. The ocean tide rises and falls in these marshes twice each day. Saltwater marshes are home to birds, crabs, fish, mussels, clams, and many other animals.  Because of the abundant food found in both freshwater and saltwater marshes, many migrating birds use them as nesting, resting and refueling stations.

Freshwater Marsh - Community of plants living in fresh water found along the shores of ponds, lakes, streams, and some rivers.
A freshwater marsh has standing water and that has mostly soft-stemmed plants such as cattails, water lilies, arrowheads, rushes and sedges. A large variety of birds, animals, insects, fish, and reptiles live in freshwater marshes. 

Bog-wet spongy ground of decomposing vegetation; has poorer drainage than a swamp; soil is unfit for planting food but can be cut and dried and used for fuel.

Watershed-It's the area of land that catches rain and snow and drains or seeps into a marsh, stream, river, lake or groundwater. The region draining into a river, river system or other body of water.

Fen-A usually low-lying area of soft waterlogged ground and standing water

Wetland Characteristics
What are the characteristics of a wetland? There are three major things to consider when determining a wetland.
1. The Water
2. The Soil
3. The Plants
Sometimes one of these factors may be enough to determine the presence of a wetland; but if they exist in combination, there is a much better chance that a wetland environment is present.
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