Riparian restoration involves returning an area to a quality of habitat that will sustain life, enhance life, or cause a return of living things. A riparian or habitat zone is associated with water and the adjoining soil that has a high moisture content. We think of riparian habitats or zones in terms of the area between where the water table starts and ends.
Riparian habitats or zones include shorelines, ponds, lakes, rivers, marshes, bogs, rivers, meadows, wetlands, streams and adjacent land, and the higher land that interacts with the area via the water table. In some cases, the actual riparian zone , such as the American Western Riparian Zones is narrowly defined as the ribbon like strip of river or stream water and the adjacent upland.
Specific zones are the water, riparian and upland zones. The water zone is the aquatic biome or habitat where aquatic plants and the water quality are an issue. The riparian zones involves sedges, shrubs, grasses,deciduous trees and rushes, such as Tules. The upland zone may have grasses and coniferous trees.
In the Western Riparian zones, the major issues are: controlling flood waters, which cause erosion and misplacement of sediment, as they can be quite forceful. Ground water, or the water table needs to be controlled in order to refill or “recharge” the water table for water during droughts. The Western riparian restoration projects are of enormous importance because of the susceptiblity to much more dryness and longer periods of drought than the Eastern areas and the coastal areas.
In addition, the water may require filtering, via reservoirs, of upland material which pollutes the water. In the West, the largest projects to create hydroelectric power and to store and release water have resulted in improvements to the violence of water flow, destructive flooding and the movement of sediment. Water pumping operations help to keep upland plants and grasses viable.
There is also temperature control to aid the species of fish that lay eggs in shallow waters. Temperature control is provided by planting grasses and plants that provide shade, for example, in a riparian restoration project.
The living creatures are provided with crucial habitat for endangered species, such as birds, mammals and invertebrates. The problems of poor timber management, overdevelopment and overgrazing can result in a loss of soil that sustains plants and trees.
In the West, many non native species of plants, animals and fish were introduced as food sources, for recreational fishing, or as ornamental or agricultural plantings. These non native species were capable of wreaking great havoc, as they ate, shut out or ran out native species.
An example is the Saltcedar ornamental and river bank stabilization plant which overtook Willow and cottonwood riparian shrubs in the American Southwest. Saltcedar created far more problems than it solved, as it takes up a lot more water, emptying priceless watering holes, and produces a lot less food.
The building of roads for timber harvests is a controversial issue. The problem with the road building is that it does three things: it destroys the soil’s capability of sustaining plant life, takes away topsoil that is not exactly abundant in the first place in higher areas, and it introduces enormous amounts of fine silt and sediment that washes downhill to pollute waterways.
Mining also has introduced sediment and pollution to waterways. The San Francisco Bay of California contains massive amounts of silt and pollutants, including mercury, from hydraulic mining in the High Sierra, hundreds of miles away.
Finally, recreational use is an important part of riparian restoration. Humans who learn to enjoy nature with care and respect now have areas to enjoy that are actually nature and not the evidence of mankind’s activity.
While there are Federal programs for riparian restoration and for the prevention of more damage, there are vast areas where private landowners are allowed to remove vegetation that prevents water bank and other erosion, to damage topsoil through overgrazing, to and to introduce non native plants that may overtake native species.
On the costal areas, the waterways, and throughout the contenents of the Earth, a dedication to riparian restoration and prevention of damage will reap great rewards for all living things.
USGS, “Western Riparian Wetlands”
http://www.americantrails.org/resources/info/glossary3.html#r
