TY JOUR TI On the unity of the processes of photosynthesis, nitrogen fixation and soil formation KW system approach KW cognition of the surrounding world KW photosynthesis KW symbiotic nitrogen fixation KW associative nitrogen fixation KW microorganisms KW root secretions KW soil formation KW system KW ecosystem KW agroecosystem KW agrobiogeocenosis KW biosphere KW rhizosphere KW soil fertility KW mineral fertilizers KW organic substances KW photosynthesis products KW ecological and biospheric agriculture JO Agrarian Bulletin of the AU Ovsyannikov, Y.A. PY 2022 IS 216 PB Ural State Agrarian University