天安门融雪剂次生盐害土壤的防治与监测

为了减轻氯盐类融雪剂对生态环境造成的污染，节约由此产生的土壤治理修复费用，针对天安门广场油松土壤的融雪剂次生盐害问题，采用铺设吸附层的方式进行了土壤防治工作。吸附层由海泡石绒、沸石、腐殖质3种吸附性材料组成，具有吸附融雪剂中Na+、Cl-等无机离子的作用，分别对铺设吸附层前后的土壤采样分析。结果表明：吸附层对土壤的pH、EC值有明显缓冲作用，可有效吸附融雪剂中Na+、Cl-，但对Cl-可能存在吸附量上限。后续的土壤监测表明，天安门广场地形及车辆行人等因素对土壤EC值有一定影响。吸附层能够吸收氯盐类融雪剂中的无机盐离子成分，在一定范围内可有效防止氯盐类融雪剂对油松种植土壤造成的次生盐害问题，改变污染状况。

Prevention and Monitoring of Secondary Deicing Salt Soil at Tian’anmen

In order to reduce the pollution caused by chlorine deicing salt on the ecological environment, and save the costs of soil remediation and repair, prevention and control of soil was carried out with a kind of adsorbed layer of deicing salt adsorption, which was made up of adsorption materials, such as sepiolite cashmere, zeolite and humus, aiming at the Tian’anmen Square in Pinus tabulaeformis planting soil secondary salinity problems of deicing salt. The laying of adsorption layer and soil were sampled and analyzed. The results showed that, the adsorption layer would absorb Na+, Cl- from the deicing salt effectively, which also had an obviously buffer action on pH, EC value of soil. However, a maximum adsorption capacity might exist when Cl- was absorbed. The follow-up soil monitoring showed that, pedestrians and traffic on Tiananmen Square and other factors had certain effect on soil EC value. The adsorption layer would absorb the inorganic salt ion composition in the chlorine deicing salt, and it would effectively prevent the secondary salt damage caused by the chlorine deicing salt on Pinus tabulaeformis planting soil, to change the pollution situation within a certain range.