Riparian Ecological Types: Gifford Pinchot and Mt. Hood National Forests Columbia River Gorge National Scenic Area

摘要

In landscape ecology terms, riparian areas are zones of interaction between surface water and the surrounding uplands or hillslopes. Like the chicken and the egg, the kind, frequency and intensity of interactions that occur are both result and causative agent of the character of riparian landforms, soils and vegetation. In other words, riparian areas reflect a variety of processes occurring upslope and instream, and they also create conditions that buffer, mitigate and shape those same processes. Furthermore, water runs downhill. As a result, not only do riparian areas integrate stream/hillslope processes in general, but downstream riparian areas integrate what is happening upstream. For these reasons, to truly understand the role of riparian areas, it is necessary to look at the landscape as a system of various structural elements (different riparian landform, soil and vegetation types) each having both an individual and a collective contribution to overall system function. Clearly, a first step in comprehending the system is to catalog and describe the individual riparian components, and to make some interpretation regarding the role they play in hill/slope/stream interactions. The purpose of this publication is to provide such a vehicle for understanding riparian ecosystems within the Gifford Pinchot and Mt. Hood National Forests and the Columbia River Gorge National Scenic Area.