Another type of wetland is called lacustrine. These are shallow lakes. Wetlands along rivers are called riverine wetlands. In Iowa, wetlands filled with groundwater are called seepage wetlands. Fens and bogs are seepage wetlands.
Bogs have lots of dead plant material in their soil.
Fens don't have as much dead plant material in their soil, and their water is different from bogs. All these kinds of wetlands perform functions . Some functions include providing habitat for birds, animals and plants, and cleaning water of nutrients and pollutants. Wetlands can even help reduce flooding of streams and rivers. These functions make wetlands important and valuable to humans.