AP Environmental Science

Answer: A - The largest environmental problem for ancient Mesopotamia was that the soil was no longer as fertile as it used to be.

Key Takeaway: Early civilizations that were of any significant size greatly relied upon the fertility of the soil in order to achieve a desired population density. Ancient Mesopotamians used farming practices and irrigation that caused the soil to dramatically lose its fertility. Much of this was due to the fact that the water used in irrigation evaporated, leaving behind a great amount of salt residue.