TY JOUR TI THE BALANCE OF TRACE ELEMENTS AND HEAVY METALS IN AGROCENOSES OF KRASNOYARSK REGION KW heavy metals KW microelements KW bal-ance KW security KW deficit KW yield KW quality JO Bulletin of KSAU AU Voloshin, E.I. PY 2017 IS PB Krasnoyarsk State Agrarian University