TY JOUR TI AGROCLIMATIC ZONES AND YIELD OF AGRICULTURAL CROPS IN THE CHANGING CONDITIONS OF REGIONAL CLIMATE KW climate change KW agro-climatic regions KW agriculture KW productivity KW growing season KW risks and opportunities JO Vestnik of Kazan State Agrarian University AU Scherbakova, A.S. PY 2021 IS 16 PB Kazan state agrarian University