New perspectives for improvement of riparian environment -- introduction of U.S. riparian management and application to Japanese landscape

Originally Japanese Erosion Control Technologies (SABO) were designed for disaster prevention andlanduse development. However, as general public concerns are widened from disaster prevention to protectionof riparian environment in Japan, SABO works have received increasing criticism. We should recognize acoming new era in which SABO cannot be used in hazardous areas for the single purpose of erosion controlwithout also protecting ecological values. The objective of this paper is to present new technical ideas toimprove riparian environment as part of SABO. Four hierarchical spatial scales of consideration are proposedas a framework for managing riparian environment; two of these scales (landscape and channel unit) werenot considered in old SABO planning. Each value, such as disaster prevention, maintenance of ecologicaldynamics, and habitat improvement, occurs at a distinctive scale in this hierarchical structure. The authorbelieves a hierarchical concept is very helpful to arrange multi-values into a coherent structure of manage-ment for riparian environment.