Abstract

Rahym Kizhdashevich Bekbayev, Nurlan Nurmahanovich Balgabaev and Yermekul Dukenovna Zhaparkulova

DOI : http://dx.doi.org/10.13005/ojc/31.Special-Issue1.29

The goal of this work is to carry out an ecological assessment of drainage water qualitative composition at Syr Daria middle course and to set factors that worsen a reclamative condition of irrigated lands during the irrigation of cultivated crops. It was found out that the salinity level of drainage water at irrigated lands of Makhtaaral area in South Kazakhstan region varies significantly 1.009-7.275 g/l. There is a lesser change range in Shardara irrigation area – 0.976-2.412 g/l and in the area of Arys-Turkestan channel – 1.031-3.449 g/l. According to the analysis of ion composition SO₄^2- is a predominant anion of Syr Daria middle course, its concentration in Makhtaaral area is high in comparison with Shardaria area and the area of Arys-Turkestan channel; it varies within 1.521-2.054 g/l or 31.68-42.80 mg-eq/l. According to the analysis of cation composition of drainage water the predominant cations of the majority of collectors are Na⁺ and Mg²⁺. If the salinity level of drainage water increases then difference in concentration of cations Na⁺ and Mg²⁺ rises sharply. It was found out that the percent of toxic salts is about 63.2-80.3% from the total salt content. Besides, for crops the most harmful toxic salt is regular sodium carbonate – Na₂CO_3, it is 10 times more toxic than chlorine.

Qualitative composition; drainage water; deterioration; soil; irrigation; ecology

[ View HTML Full Text]