ABSTRACT

Quantifying the kinematic evolution patterns of dune migration plays a major role in resisting the sand-dust disasters and evaluating the desertification process. With the increment of optical observations, measuring the dune migration with dense spatial and temporal density has become possible. In this study, with the open-accessible Landsat-8 (L8)/Sentinel-2 (S2) imagery and global terrain datasets, we designed a complete workflow of inverting the dune displacement time series and velocity, identifying the potential encroachment risk, and evaluating the sediment balance of mobilized dune fields near Dunhuang Oasis. After the performance of time-series inversion, the standard deviation (STD) of measurements in stable area of raw correlation results was improved by above 40%. The displacement time series and velocity revealed out the spatial heterogeneity and seasonal/inter-annual dynamic evolution of dune migration. Furthermore, dune encroachment risk in the immediate vicinity of local landscapes was evaluated to highlight the unstable dune fields, and the workability of existent sand-control facilities. Additionally, the mass budget of around −0.001 ± 0.025 m/yr shows the stable sediment transport in Mingsha mountain. This study case can be exemplified to lead the risk monitoring and sustainable conservation of Dunhuang region and other places controlled by similar climatic conditions.

量化沙丘迁移的运动演化模式在抵抗沙尘灾害和评估荒漠化过程中起着重要作用。随着光学观测的增加，以密集的时空密度测量沙丘迁移成为可能。在这项研究中，我们使用可公开访问的Landsat-8（L8）/ Sentinel-2（S2）影像和全球地形数据集，设计了一个完整的工作流程，可转换沙丘位移时间序列和速度，确定潜在的侵占风险，以及评估敦煌绿洲附近动员沙丘田的沉积物平衡。经过时间序列反演后，原始相关结果稳定区域中的测量标准偏差（STD）提高了40％以上。位移时间序列和速度揭示了沙丘迁移的空间异质性和季节/年际动态演变。此外，还对邻近地区景观的沙丘侵蚀风险进行了评估，以突出不稳定的沙丘场和现有防沙设施的可操作性。另外，大约-0.001±0.025 m / yr的整体预算表明鸣沙山的泥沙输送稳定。该研究案例可以作为对敦煌地区和受类似气候条件控制的其他地方进行风险监测和可持续保护的例证。以及现有防砂设施的可操作性。此外，大约-0.001±0.025 m / yr的整体预算表明鸣沙山的泥沙输送稳定。该研究案例可以作为对敦煌地区和受类似气候条件控制的其他地方进行风险监测和可持续保护的例证。以及现有防砂设施的可操作性。此外，大约-0.001±0.025 m / yr的整体预算表明鸣沙山的泥沙输送稳定。该研究案例可以作为对敦煌地区和受类似气候条件控制的其他地方进行风险监测和可持续保护的例证。