干旱区生态环境知识资源中心

Soil Salinity is one of the most important environmental factors limiting and agricultural hazard in arid and semi-arid regions. Accumulation of soluble salts within the root zone is one of the major problems because most of the crop plants are sensitive to salinity caused by high concentrations of salts in the soil. For prevail over this problem, leaching of accumulated salts and controlling soil salinity is necessary. The primary method of controlling soil salinity is to permit of the irrigation water to leach the soil, be drained and discharging through an appropriate drainage system. The objectives of this study were to introduce an empirical model to account for reclamation water and to compare the obtained results with some available models. Consequently, a large-scale field experiment was conducted in Jofeir region at south part of west Khuzestan plains, covering an area of 21285 ha with S3A3 and S3A4 salinity-sodicity classes. The intermittent pounding experiment was conducted with six double ring infiltrometers in a circular array. All experiments were accomplished by applying 100 cm of water in four-25 cm intervals. The leaching water was supplied from Karun rive. Four mathematical models were applied to the collected experimental data to derive a suitable empirical model. The results indicated that the proposed power model with maximum correlation coefficient of 0.88 and minimum standard error of 0.25 can provide reasonable estimates for leaching process compares to the previously proposed models.