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通过COSI-Corr软件处理Landsat-5 TM可以较好地量化沙丘的迁移模式和大小，为防沙治沙工程的实施提供具体的指导和建议。目前关于Landsat-5 TM迁移场误差源分析和时序反演研究仍然较少。所以，本文以毛乌素沙地西北部为研究区域获取了1991~2000年的沙丘迁移时间序列和年平均速度场，发现Landsat-5 TM迁移场的主要误差为轨道误差、姿态角误差和失相关噪声，这些误差消除后，精度相继提升23~34%、4~20%、2~5%，再利用最小二乘法反演后可提升13~14%。监测结果表明，1991~2000年毛乌素沙地西北沙丘向东南方向持续推进，最大速度可超过6 m/yr ，但受到西北-东南向的风力作用下，沿西北-东南向存在周期性往返运动；研究区域速度为0~1 m/yr的占63.9%，大于3 m/yr的则只有4.2%。Landsat-5 TM的误差消除和时序反演能有效地提高迁移场精度，进而获取更加准确可靠的时间序列，与以往研究不同的是，沙丘迁移场的误差消除和时序反演可以更细致地反映出地表沙丘的实际风能环境。
Processing Landsat-5 TM with COSI-Corr software can better quantify the migration mode and size of sand dunes, and provide specific guidance and suggestions for the implementation of sand control projects. At present, there are still few studies on the error source analysis and timing inversion of Landsat-5 TM migration field. Therefore, this paper takes the northwestern part of the Mu Us Sand Land as the study area to obtain the dune migration time series and annual average velocity field from 1991 to 2000. It is found that the main errors of the Landsat-5 TM migration field are the orbit error, the attitude angle error and the miscorrelated noise After these errors are removed, the accuracy has been improved by 23~34%, 4~20%, and 2~5% successively, which can be improved by 13~14% after inversion using the least square method. The monitoring results show that the sand dunes in the northwest of the Mu Us Sandy continued to advance to the southeast from 1991 to 2000, and the maximum velocity could exceed 6 m/yr. However, under the action of the northwest-southeast wind, there was a periodic back-and-forth movement along the northwest-southeast direction; The rate of study area is 0~1 m/yr, accounting for 63.9%, and the rate greater than 3 m/yr is only 4.2%. The error elimination and time sequence inversion of Landsat-5 TM can effectively improve the accuracy of the migration field, thereby obtaining a more accurate and reliable time series. Unlike previous studies, the error elimination and time sequence inversion of the sand dune migration field can be reflected in more detail the actual wind energy environment out of the surface dunes.