TY JOUR TI COBALT CONTENT IN AGROCENOSES SOILS OF THE OMSK IRTYSH REGION KW acid-soluble cobalt KW mobile cobalt KW soils KW agrocenoses KW omsk irtysh region JO Vestnik of Omsk SAU AU AZARENKO, Y.A. PY 2025 IS 60 PB FSBEI HE Omsk SAU