[2][self-published source] Sloughing is a relatively shallow phenomenon involving the uppermost layers of the soil.
[3] According to the Mohr-Coulomb equation, the cohesion of a soil is defined as the shear strength at zero normal pressure on the surface of failure.
[4] The shear force is a function of cohesion, normal stress on rupture surface, and angle of internal friction.
[5] Increasing water content would lead to a weaker shear strength, which in turn decreases the cohesion.
[7] Active pore water pressure can reduce the shear strength by up to 60% and lower cohesion through leaching and eluviation.