Answer:
Natural levees
Natural levees are usually formed in lowland rivers. The shape lowland rivers in a sinusoid form. This is very common in the Mississippi Floodplain, specially around the Delta in the state of Louisiana.
Swamps
A swamp is a wet forested area, with a great degree of biological diversity. Swamps are very common in the MIssissippi Floodplain, specially in Louisiana and the state of Mississippi.