Wetlands are sometimes called "
kidneys of the
landscape" because of their role in the both
hydrologic and
chemical cycles. They are often the downstream receivers of both natural and human produced wastes and
filter these polluted materials from the water supply. They
protect coastal areas,
prevent flooding and
recharge aquifers. Wetlands also provide
habitat for a large variety of animals and vegetation.
Wetland are subject to all sorts of threats by humans that include draining and filling for development or agriculture, pollution from runoff, and dredging and channelization.
Other forms of a wetland include the
swamp,
marsh,
bog,
fen,
peatland,
mire,
moor, and
muskeg.