TY JOUR TI AGROLANDSCAPE TRANSFORMATION OF AGRICULTURAL LAND CHAA-KHOL DISTRICT OF THE TUVA REPUBLIC IN TERMS OF ALTITUDINAL ZONATION KW Chaa-Khol district KW geography KW farming KW land management KW land resources KW altitudinal zonality JO INTERNATIONAL AGRICULTURAL JOURNAL AU Khangaev, A.. PY 2018 IS 1 PB Electronic science