| Description |
Riparian ecosystems in the western United States, which support a variety of wildlife in addition to stabilizing geomorphic and hydrologic forces of rivers and streams, are being degraded by a variety of factors, and therefore, require extensive restoration. Three major factors that are contributing to the degradation and destruction of riparian vegetation include overgrazing. the invasion of the exotic Tamarix species, and poplar declines due to downstream flow alteration. Due to past misuse of cattle, overstocking and mismanagement of cattle, overgrazing has caused extensive damage to riparian vegetation. Overgrazing occurs when the vegetation being grazed is unable to recover the loss in biomass the following year. Managementintensive, riparian-centered grazing systems have been successful in restoring riparian vegetation. Educating ranchers of the benefits of restoring riparian areas should improve utilization of these grazing schemes. Tamarix species, commonly known as saltcedar, have proliferated in the southwestern United States because they can outcompete native vegetation, benefit from reservoirinduced changes in downstream flows, and are extremely difficult to remove. Applying the herbicide imazapyr and improving conditions for native vegetation will help reduce Tamarix numbers and restore native riparian vegetation. Riparian poplars, also known as cottonwoods, have been reduced in numbers because reservoirs have attenuated spring flooding and / or stabilized summer downstream flows. The modified flow regimes have reduced the ability of poplars to successfully establish seedlings because of changes in the geomorphic and hydrologic forces. Promoting the 'recruitment box' and more natural downstream flow regimes by combining interest group resources will help restore riparian poplar forests in the western United States. When re-establishment of riparian vegetation does not occur naturally following corrective measures, artificial revegetation methods should be considered. Upland conditions, hydrology, geology, groundwater availability, competition from weeds and exotics, and native vegetation are all crucial elements that must be determined and understood to successfully revegetate and restore riparian vegetation. I would like to dedicate this paper to Dr. Katrina Moser (thanks for an your help and putting up with my procrastination of this paperi), Mom, Dad, Steph, and Paul. |
