Deforestation is the major causal agent of

Deforestation is the major causal agent of Desertification of habitat.
Deforestation or forest clearance is the removal of a forest or stand of trees from land that is then converted to non-forest use.
The removal of trees without sufficient reforestation has resulted in habitat damage, biodiversity loss, and aridity. Deforestation causes extinction, changes to climatic conditions, desertification, and displacement of populations.