Riparian areas are natural locations which are characterized by the presence of water. The word “riparian” is derived from the Latin word for river bank, and historically referred specifically to running water. In modern usage, however, a riparian area includes any body of fresh water, moving or still, and the land in close proximity to the water. The land near the water may be known as the riparian zone, in a reference to the fact that it is very much shaped and influenced by the neighboring water.
The characteristics of a riparian area vary widely, depending on a number of characteristics. For example, the area around a seasonal stream is generally different from that around a river which is present constantly, because different types of vegetation and animals are supported. Altitude can also play a role; an alpine riparian area, for example, will be very different from a lowland one. The climate history of the area can contribute as well, as climate helps to shape the natural landscape in addition to determining the size of water supplies.
Ecologically, riparian areas are of great importance. Healthy riparian areas provide habitat, control erosion, reduce pollution, and provide other benefits. Unhealthy ones can contribute to environmental degradation downstream. For example, if mining operations have stripped the vegetation from the banks of a river, this creates sediment which may drift downstream, carrying pollutants and changing the character of the water so that native fish species can no longer live in it.
Plants and trees which grow in riparian areas are often fond of water, and can be quite diverse. Numerous animal species also take advantage of riparian areas for habitat. Vegetation can provide nutrition for herbivores, while carnivores can take advantage of the smorgasbord of animals coming to eat and drink at the river. Health of riparian areas also has an impact on aquatic life including waterbirds and fish.
For humans, such areas can provide opportunities for recreation, but they also confer benefits such as keeping temperatures from getting too low or too high, trapping soil so that sediment doesn't ruin waterways for navigation and irrigation, filtering pollution to reduce environmental damage, and providing ample opportunities for hunting and fishing. Riparian restoration is an environmental goal in many areas of the world where people are working to restore damage caused by human activities, to help environments adapt to changing climates, and to control pollution in innovative ways.