多源数据的区域土壤盐渍化精确评估

为精确揭示区域土壤盐分的三维分异特征，将由区域遥感影像解析获得的光谱指数、面域电磁感应大地电导率仪测得的土壤表观电导率和控制点位土壤采样实测数据进行有效耦合，应用多元回归方法建立土壤盐分解译模型，利用反距离权重方法对区域土壤盐分三维特征进行插值解析与评价，创建了基于多源数据的区域土壤盐渍化精确评估方法。应用实践表明：案例研究区域各土层土壤盐分含量的变异系数在1.281~1.527之间，表现为强度变异性；土壤盐分含量高值主要集中在案例研究区域的中西部地带；区域盐渍土剖面类型大部分属“表聚型”，即随着深度增加土壤盐分逐渐减小；对案例研究区域土壤盐分三维特征解析精度达到相关系数为0.908。解决了以往多源数据耦合协同以更高精度解析区域土壤盐分特征的难题，为精确评估区域土壤盐分三维特征和其他地学空间属性解析提供了可靠方法借鉴。

Accurate Evaluation of Regional Soil Salinization Using Multi-Source Data

Due to its negative impacts on land productivity and plant growth, soil salinization is a tough problem, particularly in arid and semi-arid regions of the world. Therefore, monitoring, mapping and predicting soil salinization are of utmost importance regarding lessening and/or preventing further increase in soil salinity through some protective measures. The current study proposes an evaluating and predicting approach that is based on remote sensing (e.g., Landsat TM images), near sensing technologies (e.g., electromagnetic induction device, EM38) and soil sampling data in typical zone of Xinjiang Automonous region. Firstly, maps of soil salinity were obtained from accurate interpretation model of soil salinity using multiple regression method in study area. The uniform distribution of 3D scatter data was modelled by grid sampling point on map of soil salinity. Then, a three-dimensional soil salt distribution was characterized by inverse distance weighting method. The results showed that the coefficient of variation of soil salinity, an indicative of strength intensity variation for different seasons, ranging from 1.281 to 1.527. The soil salinity remained at a low level and it decreased with increase of depth in the study area. Map of three-dimensional distribution of the regional soil salt demonstrated that severe soil salinity located in Midwestern region of the studied area. The synthesized method based spectral indices from remote sensing, soil apparent electrical conductivity from electromagnetic induction device and data of soil sampling in this study had 0.908 of high correlation coefficient for assessment of regional soil salinity. Thus the application of this technique provides a new method to interpret and evaluate regional soil salinity in the three-dimensional spatial distribution characteristics in Xinjiang.