Vegetation-Erosion Dynamics - River Dynamics and Integrated River Management - page 71

(a)
(b)
(c)
Fig. 2.23 Vegetation succession from a pioneer suite consisting of lichen and grasses (a), to a suite consisting of
shrubs and grasses (b), and finally to a complex suite consisting of woods, shrubs and grasses on the Yunnan-Guizhou
Plateau in southwestern China (c)
Vegetation control erosion —Vegetation is the most effective form of erosion control and it is also
self-healing. Vegetation reduces erosion by ķ adsorbing the impact of raindrops, ĸ reducing the velocity
and scouring power of runoff, Ĺ reducing the runoff volume by increasing the percolation into the soil,
ĺ binding soil with roots, and Ļ protecting the soil from wind erosion (Goldman et al., 1986). On the
Loess Plateau of China the Wangjiagou Gully has a well-established forest that has trapped sediment and,
therefore, the gully bed has risen 5 m in 120 years (Li, 1993). Investigations into many small watersheds