Validation of LAI retrieval results of winter wheat in Yancheng, Luohe area of Henan Province
Hui YUAN1,4,Qiming QIN1,2,3(),Yuanheng SUN1
1. Institute of Remote Sensing and Geographical Information System, School of Earth and Space Sciences, Peking University, Beijing 100871, China 2. Beijing Key Lab of Spatial Information Integration and Its Application, Peking University, Beijing 100871, China 3. Geographic Information Engineering Technology Center of Geographic Information Basic Software and Application, Beijing 100871, China 4. 96944 Troops of PLA, Beijing 100096, China
为对比不同真实性检验方法对高分一号(GF-1)/WFV冬小麦叶面积指数(leaf area index,LAI)反演结果的验证效果,以河南省漯河市郾城区为研究区,分别采用单点测量值验证、多点采样尺度上推验证以及引入高空间分辨率影像验证3种方法对基于GF-1/WFV影像的冬小麦LAI反演结果进行了真实性检验。研究结果表明,3种验证方法得到的均方根误差(root mean square error,RMSE)分别为0.57,0.80和0.46,相关系数分别为0.885,0.508和0.867。由于基于多点采样尺度上推方法对采样点数量及其位置要求较高,因此在本研究采样点较少的情况下精度较低,效果欠佳; 另外2种方法精度相对较高,适用性较强,但其中引入高空间分辨率影像验证方法精度更高,更适用于GF-1/WFV影像LAI反演的真实性检验。
In order to compare the validation performances of different validation methods on the GF-1/WFV winter wheat LAI retrieval results, the authors chose Yancheng, Luohe City of Henan Province as the study area. Three methods, i.e., single point ground measurement validation, multi-point upscaling validation, and high-resolution result validation, were tested to verify the performance of winter wheat LAI inversion based on GF-1/WFV image. The results show that the RMSE obtained by the above three verification methods are 0.57,0.80 and 0.46,respectively. The correlation coefficients are 0.885, 0.508 and 0.867,respectively. The multi-point upscaling method has higher requirements for the number of sampling points and the position of sampling points. Therefore, the accuracy is low and the effect is poor in the case of fewer sampling points in this study. The other two methods have relatively high precision and applicability, and the validation method with the introduction of high-resolution image achieves higher precision, and hence this method is more suitable for the validation of LAI inversion of GF-1/WFV images.
袁辉,秦其明,孙元亨. 河南漯河郾城区冬小麦LAI反演结果真实性检验[J]. 国土资源遥感, 2020, 32(1): 162-168.
Hui YUAN,Qiming QIN,Yuanheng SUN. Validation of LAI retrieval results of winter wheat in Yancheng, Luohe area of Henan Province. Remote Sensing for Land & Resources, 2020, 32(1): 162-168.
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