Effects of Controlled Drainage Systems to prevent chemical soil degradation in the Area under Sugarcane Cultivation

The Imam Khomeini sugarcane agro-industry is one of ten sugarcane agro-industry plantations in Khuzestan province. As regard as the drains has been installed in this plantation many years ago so there is water and salt balance in this land that is one of the condition for implementation controlled drainage. This research was designed to investigate the possibility of using a controlled drainage system and its effect on soil salinity, sodium absorption ratio, pH and Cl- ions in three farms by three treatments. The first treatment conventional drainage, second and third treatment controlled drainage with water table controls set at 70 and 90 centimeter. Results showed that controlled drainage system does not have negative impact on soil salinity and sodium adsorption ratio. Average soil salinity In the FD, CD90 and CD70 was respectively 3, 2.16 and 2.50ds/m at the depth of 0-60cm in the beginning of period and was 1.6, 2.09 and 1.89ds/m at the end of period. Average sodium absorption ratio In the FD, CD90 and CD70 was respectively 3.68, 4.14 and 3.20 at the depth of 0-60cm in the beginning of period and was 2.71, 4.64 and 2.85 at the end of period. In the all treatment Soil pH was not significantly different between beginning and end of period. Variation in soil pH was negligible in all treatments during study period. The amount of Cl-ion in soil solution had a decreasing trend from the beginning to the end of period in conventional drainage and controlled drainage treatments.