In this way Vernadskii formulated the dependence of the fundamental property of soil upon the organisms lodged in it. According to him ,the notion of soil and its fertility are inseparable. He considers fertility an essential property, a qualitative indication of soil independent of the degree of its quantitative expression. It must be noted, that rocks also possess fertility to some degree. Investigations show that even the hardest rock massifs a are inhabited by various organisms.
Lichens develop on their surfaces and often cover large spaces on mountain tops.
The upper layer of rock massifs, the so-called weathering crust, is saturated with bacteria and algae, as well as fungi, actinomycetes, protozoa and other organisms. According to our data, in the upper layer of basalt rocks, the bacteria in one grain of substrate number from some tens of thousands to millions. Rocks differ in their fertility. Some of them are densely overgrown with lichens and microorganisms, others are sparsely covered. Tens of thousands to hundreds of millions were counted in one gram.