Describe how overcroping results in soil degradation

The more cropping you do without switching crops depletes the nutrients needed for the certain crop you are growing, Ways to combat it are rotating the crops annually (pretty sure burning the crops every once in a while as well)

B.a pop up at ion changes in response to a change in the environment.

This would be an open primary. a closed primary people can vote only prior to election day if the party if they are registered. independent voters can not participate. there is not a wide-open primary, but there is a semi-open primary.