EVALUATION OF SUITABILITY OF DRAINAGE WATER OF AL-HUSSAINIA SECTOR (KUT IRAQ) TO IRRIGATE COTTON CROP

Abstract

In this study, a specified area of Al-Hussainia sector (which is the middle sector of Al-Dalmaj irrigation project in Kut city/ Iraq) has been selected tobe evaluated for its water suitability to irrigate cotton plant. The evaluation include: first Chemical evaluation of drainage water, second Analysis of drainage water by Aq.Qa software, and third computations of Leaching requirements for cotton crop.For the chemical evaluation the most important indicators for the salinity problem considered are (Electrical Conductivity, Total Dissolved Solids, Sodium Adsorption Ratio (SAR) and Sodium Content).The analysis of the hydrochemical results by Aq.Qa program shows that the internal consistency of the samples was acceptable.It is concluded that in the months July to October most of the measured concentrations of the tested elements were greater than the other four months because in hot weather the evaporation will increase which decrease thequantity of dissolved oxygen in water which cause the increase in concentrations of these elements. However the drainage water of Al-Hussainia sector can be used directly to irrigate cotton without reducing the yield with leaching requirement of 0.18 for location 1, leaching fraction of 0.17 needed for locations 2 and 6, while a leaching fraction of 0.16 should be provided for locations 3 ,4 ,and 5. However there is no need to mix the drainage water with fresh water.