The action of returning to the surface usually has enough force to cause the entrainment of new particles. This process is only active in air and water. Traction is the movement of particles by rolling, sliding, and shuffling along the eroded surface. This occurs in all erosional mediums. Solution is a transport mechanism that occurs only in aqueous environments.
Solution involves the eroded material being dissolve and carried along in water as individual ions.
Particle weight, size, shape, surface configuration, and medium type are the main factors that determine which of these processes operate. The erosional transport of material through the landscape is rarely continuous. Instead, we find that particles may undergo repeated cycles of entrainment , transport , and deposition . Transport depends on an appropriate balance of forces within the transporting medium. A reduction in the velocity of the medium, or an increase in the resistance of the particles may upset this balance and cause deposition.