CONJUGATE PAIR OF IRRIGATED AND NON-IRRIGATED CARBONATE CHERNOZEMS OF THE SOUTH OF MOLDOVA: BALANCE OF MINERALS
The balance of minerals of the silicate part of carbonate chernozem irrigated for 11 years with good quality waters compared to non-irrigated carbonate chernozem revealed a decrease in the content of primary minerals by 56 t/ha, smectite by 267 t/ha, chlorite and kaolinite in the sludge in total by 55 t/ha. Irrigation caused additional illitization of the upper part of the profile of chernozem and an increase in the amount of illite by 56 t/ha. Loss of smectite occurred on the spot without moving it deep into the profile. Natural (before irrigation) carbonate chernozem contains signs of loss of primary and clay minerals in the volume characteristic of ordinary chernozem, which probably indicates its ancient origin and a low level of carbonates in the past.