Soil-forming minerals occurring in rocks do not contain any water, they undergo ______________ when exposed to humid conditions & break down as in chemical weathering process:
Any material such as straw, sawdust, leaves, plastic films, & loose soil that is spread upon the surface of the soil to protect the soil & plant roots from the effects of raindrops, soil crusting, freezing or evaporation:
Soil additive which stabilizes the soil, improves resistance to erosion, increases to permeability to air & water, improves texture, eases cultivation or otherwise improves soil quality: