What is soil erosion? What are the effects of soil erosion? How can we prevent soil erosion? ​

you can prevent it by mulching, maintaining a healthy, perennial plant cover, planting a cover crop, or placing stones and woodchips. Soil erosion is displacement of the upper layer of soil. The effects of soil erosion go beyond the loss of fertile land. It has led to increased pollution and sedimentation in streams and rivers, clogging these waterways and causing declines in fish and other species. And degraded lands are also often less able to hold onto water, which can worsen flooding.

the correct answer is:

a population changes in response to a change in the environment.

x would be the most and the least would be y because there are more fruit   and seeds than flock z has insects