Abstract
Rice cultivation was developed extensively in Kazakhstan in the 70-90s of the last century.More than 220 thousand hectares of rice irrigation systems were built in the basins of the Syr Darya, the Ili and Karatal Rivers.In the 90s the area of rice crops in the Kyzylorda region, in the basin of the Syr Darya River amounted to 110.0 thous.ha, in the Almaty region, in the basins of the Ili and Karatal Rivers -26 thous.ha.Operating experience of rice irrigation systems shows that for rice irrigation systems, water withdrawal from irrigation sources of the Syr Darya, Ili, Karatal Rivers is determined by their water content, water consumption of grown crops in the river basins varies widely from 15 to 35 thous.m³/ha.At the same time, it is established that plants use around 40-45% of water, taken from the irrigation sources.The rest goes to technological losses (surface discharges, seepage from channels, losses occurring during transportation of water from irrigation sources to plants).Low efficiency of water use causes water users to increase the volume of water intake by 30%, it results in a reduction of irrigation capabilities of irrigation sources and the area of irrigated land.