以天津东郊污灌区(慢速渗滤系统)为试验点,总结了土壤盐分的变化规律,并以粮地、菜地、稻地为代表分析了土壤中盐分变化动态,用污灌区土壤盐分动态平衡公式C_K-C_h=C_B-C_O测算,结果表明,只要灌区排水条件好,加上合理的科学灌溉,污灌区土壤盐分变化趋势是脱盐占主导地位,土壤中的钠吸附比(SAR)有所改善,土壤质量有所提高. In this paper, the variation law of soil salinity was summarized with the sewage infiltration zone (slow infiltration system) in the eastern suburb of Tianjin as an example. The changes of salinity in the soil were analyzed with the grain, vegetable and rice fields as the representatives. The dynamic balance formula C_K-C_h = C_B-C_O is calculated. The results show that as long as the drainage conditions are good in irrigated area and the reasonable scientific irrigation, the trend of soil salinization in sewage irrigated area is dominated by desalination. The sodium adsorption ratio Improved soil quality has been improved.