How can soil be preserved and why is it very important for humans?

The soil is self-cleaning. However, this process is very long and complex, self-cleaning capabilities of the soil are very limited. The only way to preserve the soil (and therefore the flora and fauna) is not to pollute it, use gentle methods of processing it, correctly and properly drain and irrigate it, improve the methods of wastewater treatment in industrial enterprises and cities, and use chemical fertilizers correctly in agriculture . This is very important, since soil along with air and water is an essential element of the biosphere and determines the state of the human environment.