基于EM38-MK2的滨海土壤电导率精确解译模型

Accurate models of interpreting soil electrical conductivity based on EM38-MK2

以黄河三角洲为研究对象,通过土壤样品分层采集进行室内分析获得土壤电导率(1∶5)及采用EM38-MK2在采样点测量水平和垂直模式下土壤表观电导率,应用回归及多元逐步回归模拟分析的方法,研究土壤表观电导率与不同深度土层土壤电导率的相关性,并进行精度验证,以获得基于新型电磁感应仪的不同剖面深度处土壤电导率精确解译模型,实现区域尺度土壤盐分在不同剖面深度处空间分布格局快速评定.研究结果表明:多模式下测定的土壤表观电导率与不同土层土壤电导率呈现不同程度的显著性相关;联合多模式下土壤表观电导率解译土壤电导率的精度高于单一模式;表层土壤电导率协同土壤表观电导率可以提高亚表层及底层土壤电导率的预测精度.本研究可以为快速调查土壤盐渍化及盐渍土改良与利用提供思路,以节约成本和提高效率.

Takes the modern Yellow River Delta as the object of study,soil electrical conductivity( 1∶5) was measured in laboratory by collecting soil samples stratified and apparent soil electrical conductivity in horizontal and vertical mode measured at the sampling points by EM38- MK2. In order to investigate models to interpret soil conductivity based on electromagnetic induction meter( EM38-MK2),the relationship between soil electrical conductivity at different depths and soil apparent electrical conductivity under different modes respectively was studied using regression and multiple stepwise regressions to assess soil salinity distribution pattern rapidly at different depth in regional scale. The results show that soil apparent electrical conductivity of each mode has a significant correlation with soil electrical conductivity at different soil layers. Interpretation accuracy of soil electrical conductivity is higher in combined soil electrical apparent conductivity of each mode than that single-mode; predictionaccuracy of electrical conductivity for subsurface soil and deep soil are increased by combining soil apparent electrical conductivity with surface soil electrical conductivity. The results may provide ideas for rapid measurement and evaluation of soil salinization and saline soil improvement and utilization to save costs and improve efficiency.