M. Shiba, Tactical sediment yield control to mitigating terrestrial and/or aquatic environmental impacts of forest road construction, FOR SCI, 54, 1998, pp. 51-66
Many studies have been identified forest roads as major non-point source im
pact contributors of sediment resulting from forest activities in mountain
environment. Thus, sediment deposits on slopes below roads make an importan
t environmental issue of management approaches to riparian zones because of
the numerous ecological linkages between terrestrial and aquatic ecosystem
s. This paper demonstrates a PC-based imagery data processing system using
digital orthophoto through the application to estimate the granitic sedimen
t deposits eroded from roads constructed on watersheds in the mountains of
Shiga Prefecture. The results showed the same time trends in sediment yield
as earlier studies that documented large areas of sediment deposits during
the earlier years after road construction followed by a rapid reduction in
deposits in subsequent years. Also, a relationship was developed to descri
be the area percent of the sediment accumulated on the slope in relation to
the travel distance.