黑河流域2019—2020年地表形变InSAR监测与生态响应分析

InSAR monitoring and ecological response analysis of surface deformation in Heihe River Basin from 2019 to 2020

摘要

【目的】黑河流域是我国西北干旱—半干旱区第二大内陆河流域，已有研究大多集中在对其生态环境开展研究，对其内旱作农业地下水开采和矿产资源开发等相关地表形变的研究不足。【方法】针对黑河流域地表稳定性监测需求，采用一种改进型IPTA-InSAR技术对2019—2020年间覆盖研究区域的两个轨道共计101景Sentinel-1卫星SAR影像进行解算，获得地表形变序列，利用邻轨重叠区独立解算结果进行可靠性验证，并结合高分辨率光学遥感数据对形变特征进行综合分析。【结果】结果显示：邻轨结果间均方根误差为0.2 mm/a;揭示流域内存在6处显著形变区：最大年平均沉降速率达56 mm/a,沿卫星视线向最大季节性沉降和抬升量达-70 mm和60 mm。【结论】时空分布特征表明，形变机制具有显著异质性：(1)中游绿洲灌区因季节性地下水超采引发周期性沉降；(2)酒泉东部长城沿线盐碱地受雨季地下水抬升影响发生季节性回弹；(3)金昌露天矿与山丹煤矿区因开采活动导致持续沉降。成果可为流域水资源优化配置、矿区开采动态管控及生态脆弱区保护提供科学依据，并对西北内陆河流域人地系统协调发展提供重要参考。

Abstract

[Objective] The Heihe River Basin(HRB) is the second-largest inland river basin in the arid to semi-arid region of northwest China. Existing studies have mostly focused on its ecological environment, while research on surface deformation related to groundwater extraction for dryland agriculture and mineral resource exploitation remains insufficient. [Methods] In response to the need for surface stability monitoring in the HRB, an improved IPTA-InSAR technique was employed to process a total of 101 Sentinel-1 SAR images from two orbital tracks covering the study area from 2019 to 2020, generating a time series of surface deformation. The reliability of the result was verified using independently processed data from overlapping adjacent tracks. Furthermore, high-resolution optical remote sensing data were integrated to comprehensively analyze deformation characteristics. [Results] The result showed that the root mean square error between adjacent track result was 0.2 mm/year, and six significant deformation zones were identified within the basin. The maximum annual average subsidence rate reached 56 mm/year, and the maximum seasonal subsidence and uplift along the satellite line of sight were-70 mm and 60 mm, respectively. [Conclusion] The spatiotemporal distribution characteristics indicate significant heterogeneity in deformation mechanisms:(1) periodic subsidence due to seasonal over-extraction of groundwater in midstream oasis irrigation areas;(2) seasonal rebound influenced by groundwater rise during the rainy season in the saline-alkali lands along the Great Wall in eastern Jiuquan; and(3) continuous subsidence caused by mining activities in the Jinchang open-pit mine and Shandan coal mining areas. The findings of this study can provide a scientific basis for the optimized allocation of water resources in river basins, dynamic regulation of mining operations in mining areas, and protection of ecologically vulnerable zones, and offer important references for the coordinated development of human-land systems in the inland river basins of Northwest China.

关键词

InSAR / 黑河流域 / 形变监测 / 农业灌溉 / 生态健康 / 影响因素

Key words

InSAR / Heihe River Basin / deformation monitoring / agricultural irrigation / ecological health / influencing factors

基金资助

国家自然科学基金项目(42404022)

陕西省煤田地质集团有限公司科技研发项目(SMDZ-2023CX-1)