The sawing and grinding action of rock fragments in the water is called what?

Abrasion

Abrasion is a geological phenomena in which weathering and erosion of the rocks or other hard surfaces by physical agents like water and wind. In this process, the surface material is scrapped, scratched and wear down by the frictional force exerted by the physical agents.

The sawing and grinding action of the rock fragments in the water is called as abrasion because here the water is the physical agent affecting the physical structure of the rock.

increase soil erosion                                             reduce soil erosion

cattle grazing                                                         hydroseeding

deforestation                                                         contour plowing

                                                                                planting vegetation

plant roots basically hold the top soil

together and stop soil erosion because

in such situation top soil is not removed

during flood but cattle grazing causes

soil erosion because cattle consume the

grasses and herbs and top soil is exposed.

same situation occurs because of

deforestation, the trees and plants are cut

down to expose top soil which causes soil

erosion