基于SBAS-InSAR技术的洞庭湖洲滩地表形变监测

Surface deformation monitoring of Dongting Lake beach based on SBAS-InSAR technology

针对洞庭湖区水位波动范围较大,导致基于InSAR技术形变监测在湖泊洲滩区域会出现严重的失相干问题,该文利用2017年3月—2022年12月间枯水期的Sentinel-1A卫星数据,采用小基线子集干涉合成孔径雷达方法,获得洞庭湖洲滩地表形变监测结果,揭示其时空变化;研究湖区冲淤变化、降水以及人类活动等因素对洲滩地表形变的影响。结果表明:①洞庭湖洲滩地区的地表形变时空分布不均,且大部分地区的形变速率在-6 mm/月~6 mm/月之间;②枯水期洞庭湖洲滩地表形变与降水事件呈负相关;③洲滩地表形变主要是由湖内泥沙冲淤引起的,这与降水变化和湖区水体覆盖动态变化密切相关。

In response to the large fluctuation range of water level in the Dongting Lake area,which leads to serious incoherence issues in deformation monitoring based on InSAR technology in lake and beach areas,this article uses Sentinel-1A satellite data during the dry season from March 2017 to December 2022,and uses a small baseline subset interferometric synthetic aperture radar method to obtain surface deformation monitoring results of Dongting Lake and beach areas,revealing their spatiotemporal changes;Study the effects of factors such as erosion and sedimentation changes,precipitation,and human activities in the lake and beach areas on the surface deformation of the shoals.The results indicate that the spatiotemporal distribution of surface deformation in the Dongting Huzhou Beach area is uneven,and the deformation rate in most areas ranges from-6 mm/month to 6 mm/month;②-There is a negative correlation between surface deformation and precipitation events in Dongting Lake during the dry season;③The surface deformation of beach areas is mainly caused by the erosion and deposition of sediment in the lake,which is closely related to changes in precipitation and dynamic changes in water cover in the lake area.