Screening Of Amendments For Quick Desalination Of Heavy-textured Coastal Saline Soil

Coastal saline soil covers a large area in China, and it is an important land resource in coastal areas. In the current study, a range of amendments were mixed with a heavy-textured coastal saline soil at different application rates, which were packed in columns and leached with water. Soil pH and electrical conductivity have been evaluated before and after leaching experiment. The concentration of sodium in leachate was determined periodically. This study further screened the best amendments which may provide a solution for the treatment of coastal saline soil. The main findings are as following.(1) The concentration of heavy metals in the soil amendments used in this experiment were lower than those of the relevant national standards, and were safe to be used as soil amendments.(2) The results showed that the sodium concentration in the leachate was significantly higher than that in control(P<0.05). The sodium loss efficiency of 0.5% desulfurization gypsum + 1.5% biochar treatment was 1.3 times higher than control after 60 d, and this treatment was the most effective in removing sodium from the soil.(3) After application of the soil amendments, the electrical conductivity and pH values of soil samples were reduced significantly(P<0.05). The desulfurization gypsum + biochar treatment was the most effective in reducing the electrical conductivity and p H value of the soil.In summary, adding desulfurization gypsum + biochar to soil can accelerate the desalination process of the coastal saline soil, which may achieve the goal for the reasonable utilization of the coastal saline soil resources.