基于双线圈EM38的长江口土壤盐分特征研究  

Study on the soil salinization characteristic of the Yangtze River estuary area with EM38 two-coiled electromagnetic induction

作　　者：谢文萍[1] 杨劲松[1] XIE Wenping;YANG Jingsong(State Key Laboratory of Soil&Sustainable Agriculture,Institute of Soil Science,Chinese Academy of Science,Nanjing 210008,Jiangsu,China)

机构地区：[1]土壤与农业可持续发展国家重点实验室/中国科学院南京土壤研究所,江苏南京210008

出　　处：《水利水电技术（中英文）》2022年第S01期85-89,共5页Water Resources and Hydropower Engineering

摘　　要：运用双线圈电磁感应仪EM38进行河口区土壤盐渍化采样,并结合回归模型与地统计方法对长江河口北支入海口区域进行土壤电导率的空间变异研究。研究表明:双线圈EM38大地电导率仪增添了两个深度土壤表观电导率的测量,对不同深度土壤盐分含量的表征效果较好,相关系数均达到显著水平。土壤盐分的垂直分布规律显示,东部距江海较近区域土壤盐分呈现表聚型,北部西部地区土壤盐分多呈底聚型,与研究区域地下水条件有一定关联。统计分析表明,土壤电导率表层变异性高于其他层次,表层土壤电导率的平均测值也较高。土壤电导率空间分布显示,以距入海口和江堤越近土壤盐分含量越高,且随着距入海口和江堤距离增加,盐分含量增加。沿江沿海地区土壤盐分含量较高,且由于地下水位较高土壤盐分有表聚风险。A two-coiled electro magnetic induction EM38 is applied in the Yangtze River estuary, in order to study the spatial variability characteristics of soil salinity in spatial and vertical scale, with the help of geostatistics technology and traditional sampling. The result shows that the related coefficient of apparent electrical conductivity(EM38) and soil electrical conductivity all achieve 1% significance level, and the stepwise regression equation is established with four EM38 measured values and the EC_(1:5), and the result itself shows good correlation. Statistical characterization of salinity shows that the top-soil salinity displayed a larger variability and higher values than that in the deep layers. The soil salinity presents moderate spatial variability, and variability of the soil salinity decreases with the depth increase. Soil salinity spatial distribution shows that the salinity has the trend of gradually reduce from south to north and east to west, and with the depth increase, the soil salinity displays reducing trend. EM method provides a quick and accurate method for large area soil salinity sampling using the apparent electrical conductivity in interpreting the soil EC;, and the result truly reflects the soil salinization condition of this area. Sampling result shows that soil salinity in the area that near the ocean and Yangtze River is higher than the inland, and soil salinity near the estuary increases.

关 键 词：双线圈电磁感应仪 土壤电导率 表观电导率 空间变异 半方差函数 

分 类 号：S156.41[农业科学—土壤学]