As plants grow they will use the minerals found in the soil as well as humus.

These minerals as well as the Organic Matter need to be replaced. Not doing it will accelerate the depletion of the soil or the erosion.

What are the consequences of an eroded soil?

Many as a matter of fact.

1. The soil will dry out rapidly and require more and more water
2. Less humidity in the soil means less micro organisms
3. The soil loses fertility
4. More and more chemicals will be needed every year which in turn will accelerate the soil erosion
5. Often the use of chemical fertilizers is coupled with the use of chemical pesticides or insecticides which have a negative impact on the soil as they also kill all forms of life in the soil (i.e. soon no micro organisms)