Riparian wetlands are found in low-lying regions adjacent to rivers and streams that are periodically subjected to overbank flooding. These wetlands generally occur in the upper reaches of watersheds. Fringe wetlands adjacent to lakes and estuaries are also hydrologically connected with uplands and aquatic ecosystems. However, the range of hydrologic influence in the landscape is somewhat limited for lake fringe wetlands compared to riparian wetlands, the difference being the reduced throughput of water in lake systems relative to rivers and streams. The source of water to a wetland can be a major determinant of water chemistry as well as overall ecological structure and function of the wetland.
Common examples are bogs, pocosins and wet prairies.
Also included in this group are the Okefenokee Swamp in southern Georgia and the Everglades of south Florida, in its original condition. Deep groundwater normally contains relatively high concentrations of dissolved minerals, especially calcium and magnesium. Many depressional wetlands are fed primarily by groundwater, most notably fens in northern climates. Cypress domes, which are widely scattered throughout Florida, may receive most of their water from very shallow groundwater in surrounding pine flatwoods, therefore their water chemistry often resembles that of a rainfall-dominated wetland. Many riparian wetlands receive groundwater inputs from the surrounding watershed, in addition to surface water from river flooding.