Leaching Treatment of Acid Sulphate Soil and Crop Adaptation Test under Micro Scale Condition

Abstract

Agricultural problem on acid sulphate soil is related to high concentration of iron and aluminum which can be toxic to crops. The research objective was to determine soil leaching intensity or frequency effect on decreasing iron and aluminum concentration. Results from this research information can be used to develop field strategy in order to determine time and period for land leaching. Moreover, crop adaptation toward leached soil was conducted on corn crop. Experiment was conducted in laboratory of soil physics department of soil science. Duration of leaching was set up in the 5, 10, 15 days. The pH of iron and aluminum was analyzed before treatment. Iron content was at 11.58 ppm and pH was at 3.29. The result showed that the leaching option had highly significant effect on the increasing pH and reducing iron content. The pH was increase at 3.85, 4.07, 4, 26 and 4.34 respectively for 5, 10 and 15 days of leaching. It was also followed by reducing iron content of 9.29, 7.08 and 5.06 respectively for 5, 10 and 15 days of leaching. Within 15 day (two weeks duration) it was sufficient time to facilitate leaching process in the field. Climatic data showed that the rainfall was available during land preparation stage (November for first crop and March for second crop). On the other hand, the drainage facility should be developed in tertiary block to leach out the toxic element in the roots zone. This process should be done in the beginning of rainy season. Adaptation toward corn crop showed that 5 times leaching treatment was sufficient to provide good environment for crop’s growth.