Concept:Deforestation is the loss of forest cover caused by human activities that destroy or reduce trees.
Explanation:Cutting trees for farming clears forest land.
Cutting trees for timber directly removes forest resources.
Excessive bush burning and grazing destroy young trees and ground cover.
Shifting cultivation involves farming on a piece of land and later leaving it fallow.
During the fallow period, the land is allowed to recover and trees can regrow.
Therefore, shifting cultivation itself does not reduce forest cover permanently.
Answer:Deforestation occurs in all the listed cases except shifting cultivation.