基于多波段MODIS遥感数据的乌审旗土壤含水量监测研究

Soil Moisture Monitoring Based on Multichannel MODIS Remote Sensing Data in Wushen Banner

[目的]探究内蒙古自治区乌审旗地区土壤含水量与表观热惯量的响应关系,提高土壤含水量遥感监测精度,使观测分析结果更具说服力和可靠性。[方法]选取多波段MODIS遥感数据和表观热惯量法,采用重复的地面采样方案设计,减弱单点采样代表性差的影响。[结果]该方案设计较单点采样方法相关系数有明显提高,对0—10cm,0—20cm,0—30cm土壤含水量相关系数分别为0.587,0.658和0.650。对回归模型进行精度验证,得其含水量平均相对误差为21.53%,26.67%,22.83%。[结论]重复的地面采样方案下,基于表观热惯量的乌审旗土壤含水率监测结果更加科学、可靠。

[Objective]The relationship between soil moisture content and the apparent thermal inertia was examined based on the data collected from Wushen Banner of Inner Mongolia,to improve the monitoring accuracy of soil moisture content and to make the results more convincing and reliable.[Methods]Multi-band MODIS remote sensing data and ATI（apparent thermal inertia）method were used.A point-repeated ground sampling scheme was adopted to diminish the poor representativeness of single sampling method in a point.[Results]It was indicated that the correlation coefficient in the present design was significantly higher than that of single sampling method.For the relationships observed in the soil layers of 0—10cm,0—20cm and0—30cm,the coefficients were all high,with values of 0.587,0.658 and 0.650,respectively.The above regression models had different goodness with their averaged relative errors in predicting the measured water content.The averaged relative errors were 21.53%,26.67% and 22.83%,respectively.[Conclusion]Under point-repeated sampling scheme,the ATI-based monitoring results of water content in Uushen Banner were more reliable.