What impact did overgrazing have on afro-eurasian lands

The effect did overgrazing have on Afro-Eurasian grounds is that it made the terrains go dry, which made individuals not have the capacity to develop trims any longer so they needed to move out of Eurasia. 
99 percent of the dry prairie of Champagne was transformed into concentrated yield developing fields after World War II, making many feathered creature species vanish. This example has been rehashed in many parts of the world where human populaces are rising.

Iraq because its lack of policing and government concern