为获知苏北滩涂区土壤水盐动态行为,从而为后续的节水灌溉和滩涂区农田水管理策略提供理论依据,该文选取典型滩涂区,进行土壤水、盐和地下水埋深的长期连续监测,并根据大丰市气象站提供的降水、地表蒸散数据,对土壤盐分变化和水平衡要素之间的关系进行探讨。结果表明:土壤表层盐分最高,波动最为剧烈,随深度不断增加,盐分逐渐降低,且波动趋缓。试验区夏季降水丰富,蒸散量相对较低,土壤含水率高,地下水埋深浅;冬季降水少,蒸散量较高,土壤含水率下降,地下水埋深较深。地下水埋深和水补充量是0~40cm土层土壤盐分的主要影响因子;地下水埋深和蒸散量是60~80cm土层土壤盐分的主要影响因子。地下水盐分是土壤盐分累积的主要来源,降水脱盐作用仅对0~40cm表土作用显著,蒸发积盐作用则在整个土壤剖面上具有影响。该研究为消减苏北滩涂区土壤盐渍化灾害提供了科学依据,对指导农业生产具有重要意义。
For the sake of identifying the dynamic behaviors of soil water and salt,and then providing a theoretical basis for the strategies of water saving irrigation and farm water management in the coastal area of North Jiangsu Province,a long-term and continuous monitoring of soil water content,soil salt content and groundwater level was conducted in the typical coastal area of Dafeng City,Jiangsu Province. The relationships between soil salt dynamics and factors of waters balance were discussed according to the data monitored and those(precipitation,soil surface evapotranspiration data) provided by weather station in Dafeng City. The results showed that soil salt of surface layer was highest and its salt fluctuation was most activated,and soil salt gradually decreased with depth. Soil water content and groundwater level were increased in summer due to rich precipitation and little evapotranspiration,while decreased in winter due to little precipitation and plenty evapotranspiration. The salt in groundwater was the main source of salt accumulation in the profile. Groundwater level and water complement amount were the main impact factors of soil salt at 0-40 cm depth. Groundwater level and evapotranspiration were the main impact factors of soil salt at 60-80 cm depth. The desalting role caused by precipitation significantly affected the soil at 0-40 cm depth,while the salt accumulation role induced by evapotranspiration affected the soil in the profile. The study provides scientific basis for the recede of soil salinization in the coastal area of North Jiangsu Province,and possesses great significance in directing local agricultural production.