Soil is a finite resource. Like fossil fuels and water there is no limitless supply of it. As such, we need to preserve it and care about its quality, as without a healthy, vibrant soil, our ability to survive is severely compromised.
However, as the study in this article points out, as a species we are failing to do that. It shows how agricultural practices and other human activity deplete the soil at a much greater rate than any natural cause can do. It is a warning that we must all heed, and should prompt us to take care of the earth.