Discuss some of the ways humans are affecting global soils

Question

What will be an ideal response?

Answer 1

Answer: Soils are at the interface between the lithosphere and biosphere, and is a critical regulator of the hydrologic cycle. The quality and quantity of soil is being transformed by erosion, accelerated by cultivation. Erosion removes the uppermost part of the soil, which is usually the most fertile part. This removes both nutrients and the ability to store them.

In many agricultural regions, topsoil loss has ranged from 1 or 2 inches to 4 inches to a foot or more. Desertification, a process by which semiarid vegetation and soil become more desert-like as a result of human use, has occurred in semiarid lands around the world. As a result, many fewer animals can be supported by the available forage. Even though the climate of these regions has not yet seemed fundamentally altered, the land appears more desert-like than it did before excessive exploitation by humans.

Worldwide, large amounts of organic carbon are stored in soils, but agricultural activities have contributed to the loss of that organic carbon from soils. Some of this carbon has been buried with sediments eroded from farm fields, and some has been broken down and may have contributed to increased atmospheric CO2. Improved farm management practices that conserve soil also help restore soil organic matter, and are being promoted as a way to offset emissions of carbon to the atmosphere.