基于探地雷达包络检波的新增耕地有效土层厚度估算

Estimation of Effective Soil Layer Thickness of Newly Increased Cultivated Land Based on GPR Envelope Detection

目的:新增耕地土壤人为扰动大,有效土层厚度分层信息不明显,仅凭开挖剖面调查不易获取,因此探究探地雷达估算新增耕地土壤有效土层厚度的方法。方法:基于探地雷达采集电磁波,运用包络振幅平均值法(AEA)建模获取新增耕地不同剖面层次含水率与雷达振幅包络值的相对关系,通过Topp经验公式反推各层次介电常数,利用包络检波获取土壤有效土层厚度分层界面时域信息,结合介电常数和时域信息,估测有效土层厚度。结果:不同土壤剖面层次AEA^(-1)-含水率回归模型预测集R 2均在0.818以上,反演效果较好;有效土层厚度估算值相对误差在4%以下,误差较小;不同原利用类型的新增耕地有效土层厚度呈现果园>其他草地>设施农用地>城镇住宅用地。结论:基于探地雷达探测新增耕地土壤有效土层厚度是可行且较为精准的。

Objective:The effective soil thickness stratification information is not obvious,and it is not easy to obtain only by excavation profile survey.In order to quickly and accurately obtain soil stratification information.Methods:The dielectric constant of each level was inverted by the Topp empirical formula,and the time domain information of the soil effective soil thickness layering interface was obtained by using the envelope detection,and the dielectric constant and time domain information were combined to estimate the effective soil thickness.Results:The prediction set R 2 of the AEA^(-1)-moisture content regression model at different soil profile levels is above 0.818,and the inversion effect is better.The extraction of the effective soil thickness layering time domain of the newly added cultivated land is completed based on the envelope detection,and combined with the radar wave velocity of each layer,the measured value is below 4%,and the error is small.The effective soil thickness of the newly added cultivated land of different original utilization types is presented,and the agricultural land of orchards>other grassland>facilities>urban residential land.Conclusion:Based on the ground-penetrating radar,it is feasible and accurate to detect the effective soil thickness of the newly cultivated land.