The result is an area of stillness and tranquillity where fish breed, wildlife takes refuge, and local people earn a living from occupations as diverse as charcoal burning and bee keeping. Floodplains are areas of land seasonally flooded by rivers and lakes, and are found in many parts of the world. One of the most significant is Kafue in Zambia. In contrast to constantly changing floodplains, bogs are still and moist. Largely fed by gentle rainfall, they contain organic matter that slowly builds up over many years to form rich deposits of peat.
Fens also produce peat, but unlike bogs they are nou rished by streams and rivers.
Marshes slow down the rate of rainfall drainage and control its flow into rivers, lakes, and streams. Stretching along the coasts of the Netherlands, Germany, and Denmark is the marshy, salty, and sandy Waddensee - part of the North Sea. The water is shallow, so the seabed is exposed when the tide ebbs. Hundreds of seals and millions of migratory birds are attracted to the Waddensee's mudflats, sand bars, salt marshes, and barrier islands, which together are among the most important feeding grounds in northern Europe. This wetland also supports 80 per cent of the North Sea's plaice stocks, half the sole, and nearly all the herring.