Study of Moisture and Salt Distribution in the Root Dustribution Zone of Wheat Irrigated with Main Outfall Drain (MOD) Water in the Northern Sector/Abu_Ghraib Area

Abstract

     A field experiment was carried out in the northern sector of the Main Outfall Drain (MOD) water, which is the first part of the (MOD) water, starting from the outfall of the Al-Ishaqi project in the north of Baghdad to Wasit Governorate. The study site was chosen in Abu Ghraib / 12 of Al-Fakhriyah District during fall 2022-2023. Experimental treatments included: The first treatment (I₁) is Irrigation with (MOD) water throughout the growing season (after depleting 50% of available water). The second treatment (I₂) is irrigation with the (MOD) water throughout the growing season + 20% leaching requirements, while the third treatment (I₃) is irrigation with (MOD) water throughout the growing season + 40% leaching requirements. The results showed that the volumetric moisture content at all stages of wheat growth and for all soil depths of 0-0.10, 0.10-0.20, 0.20-0.30, and 0.30-0.40 m was good, with a moisture content higher than the moisture at the permanent wilting point of 0.15 cm³/cm³, which means provides available water for the plant. The results also showed a decrease in electrical conductivity with depth and for all treatments, and it was reduced in the 20% and 40% leaching requirements. However, the distribution and accumulation of salts in the soil profile decreased with the increase in the ratio of the leaching requirements for irrigation water and the irrigation frequency for all treatments and depths.