Salinization of the Fertile Crescent, Civilization Collapse

Over-farming in the fertile crescent leads to desertification, salinization, and the destruction of ancient Sumeria. "When irrigation water raised the natural water table and evaporated, salts accumulated. Poor drainage, made worse by the silt that had been deposited, made it hard to correct the situation by leaching salt from the fields with fresh water. Ground water became more and more saline . . . Over large areas the ground became so saline that white salt crystals could be seen on the surface and cultivated plants were unable to grow . . . The once flourishing cities of ancient Sumeria — Uruk, Ur, and the others — are now abandoned mounds in a desert environment . . . They represent an ecological disaster caused by overuse and eventual exhaustion of the land."