Effect of cotton, maize, and sesame cultivation on soil depletion and a comparison of its effect on chemical properties

Abstract

The study site was selected within the greenhouses at the University of Mosul in Nineveh Governorate, northern Iraq. Cotton and sesame seeds were sown on June 3, 2025, while maize seeds were sown on July 3, 2025. The cotton and sesame crops were harvested on November 10, 2025, and the maize was harvested on December 5, 2025. Soil samples were collected from the topsoil (0-30) cm at the study sites, with three replicates per site, after the harvest. DAP fertilizer (0:46:18) and urea fertilizer (46%) were used to fertilize the cotton, maize, and sesame soils to increase crop productivity and to determine effecting of intercropping on soil fertility. A sprinkler irrigation system was installed on the greenhouses to spray the crops using water from the Tigris River. The results showed that the soil acidity in all the soils studied was neutral, slightly inclined towards alkalinity, ranging from (7.20) in the maize soil to (7.35) in the cotton soil. soil electrical conductivity degree, it ranged from (0.50 dS m-1) in the maize soil to (0.75 dS m-1) in the sesame soil. Therefore, all the soils of the study sites are considered good in terms of electrical conductivity and safe for all cultivated crops. This is reflected in the good concentration of cations and anions in the soil and is safe for cultivation. The results obtained a clear difference in soil depletion degree among the studied crops after the end of the experiment and the harvest of the (cotton, maize, and sesame) crops. It was found that cotton had the highest stressing effect on the soil, followed by maize, while sesame had the least effect on nitrogen and phosphorus. The nitrogen percentage ranged between (21.6, 36.3, 91.0) mg kg-1 for the soils of cotton, maize, and sesame crops respectively, while phosphorus percentage ranged between (31.5, 38.0, 45.0) mg kg-1 for cotton, maize, and sesame crops soils respectively.