DEFORESTATION AROUND THE WORLD - India Environment Portal

100
Deforestation Around the World
After the soil is moistened, the cohesion between soil and the root surface is reduced greatly
(to negligible strengths 50% granular material concentration, especially when boulders are
entrained. Panels (b), (c) and (d) illustrate a full life cycle of the debris flow: (b) initiation, (c)
sliding, and (d) cessation. Precipitation generated surface runoff washes the fine-grained
material downslope. Because the steepness of the slope is graded (steep at top and gentler at
the toe), granular material (saturated soils) are thicker toward the toe of the slope. As the
sliding material run downslope, it entrains the pebbles and small stones (granular material) at
the bottom. This will significantly change its rheological properties as it becomes drier and
more viscous. The sliding material eventually ceases at places with gentle slopes, or where the
slope angle reverses. In the lowest inset panel, the cracked rice paddy is indicative of effects of
roots on holding the soil particles together: almost all rice bundles are located at the centers of
the cracked cells. Major cracks rarely run directly across a bundle of rice sprouts.