The deposition of material suspended in a liquid. Sedimentation is normally considered a function of water deposition of the finer soil separates of sand, silt, and clay, but it may also include organic debris. Sometimes this is referred to as the siltation process, although there may be other fractions of material present other than silt. The term can be applied to wind-transported sediments as well. Sedimentation can be both harmful and beneficial. River and stream channels, reservoirs, and other water bodies may be degraded because of the deposition of sediment materials. Many of the most important food- and fiber-producing soils of the world have been developed from the deposition of fine particulates by both water and wind. In some cases, large topographic land forms are the result of long-term sedimentation processes.