Because it can take one year to form just a few centimeters of new soil, it is important to protect Earth's soil.

If a farmer plants a field with different crops each year, the soil becomes less fertile, a situation called nutrient depletion.

Without soil, most life on land could not exist.

The structure of fertile soil contains layers including litter, topsoil, ___________________, and bedrock.

Strip mining exposes soil and causes

When soil becomes depleted, farmers usually apply fertilizers, which include _______________ that helps crops grow together.

One cause of desertification is _______________, a period when less rain than normal falls in an area.

___________ is the layer of soil where the most water and nutrients are absorbed by plant roots.

The process of restoring an area of land to a more productive state is called ________________.