Formation of modern soils is controlled not only by parent rocks (lith
ogenic factors) but mainly by the soils of preexisting biogeocenoses (
ecosystems). Soils develop through two principal processes: eluvial (n
ormal pedogenesis according to Dokuchaev) and deposition (abnormal ped
ogenesis). In the former case, the diversity of soil cover is signific
antly less when compared to the latter. The type of soil formation lik
ely affects the biological diversity of plants and pedofauna.