TY JOUR TI The qualitative composition of the humus of chernozem leached in crop rotations of the northern forest-steppe of the Southern Urals KW leached chernozem KW humus KW fulvic acid carbon KW humic acid carbon KW mineral fertilizers KW crop rotation JO Agrarian Bulletin of the AU Shatalina, L.P. AU Anisimov, Y.B. AU Kalyuzhina, E.L. PY 2022 IS 224 PB Ural State Agrarian University