Biological activity is a good indicator in soils. The following examined parameters will be presented: ratio of anaerob and aerob microorganisms (bacteria, fungi); the density and diversity of earthworms, nematoda, collembola; and the phosphatase, dehydrogenase enzyme activity. These examined properties can be used as indicators to measure soil biological activity, and condition, in other words, soil health. The biological activity in the examined Chernozem soils, which represent different level of erosion and other types of soil degradation, will be presented on this poster.