AN ECOLOGICAL PERSPECTIVE OF RIPARIAN AND STREAM RESTORATION IN THE WESTERN UNITED-STATES

There is an unprecedented need to preserve and restore aquatic and rip arian biological diversity before extinction eliminates the opportunit y. Ecological restoration is the reestablishment of processes, functio ns, and related biological, chemical, and physical linkages between th e aquatic and associated riparian ecosystems; it is the repairing of d amage caused by human activities. The first and most critical step in ecological restoration is passive restoration, the cessation of those anthropogenic activities that are causing degradation or preventing re covery. Given the capacity of riparian ecosystems to naturally recover , often this is all that is needed to achieve successful restoration. Prior to implementation of active restoration approaches (e.g., instre am structures, channel and streambank reconfiguration, and planting pr ograms), a period of time sufficient for natural recovery is recommend ed. Unfortunately, structural additions and active manipulations are f requently undertaken without halting degrading land use activities or allowing sufficient time for natural recovery to occur. These scenario s represent a misinterpretation of ecosystem needs, can exacerbate the degree of degradation, and can cause further difficulties in restorat ion. Restoration should be undertaken at the watershed or landscape sc ale. Riparian and stream ecosystems have largely been degraded by ecos ystemwide, off-channel activities and, therefore, cannot be restored b y focusing solely on manipulations within the channel. While ecologica l restoration comes at a high cost, it also is an investment in the na tural capital of riparian and aquatic systems and the environmental we alth of the nation.