北麓河流域不同植被覆盖条件下土壤冻融过程中地表土壤含水量变化  

Changes in surface soil mositure during freeze-thaw process under different vegetated status using Sentinel-1A in Beiluhe

作　　者：胡越中 王广军[1] 杜海波 梁四海[3] 罗银飞 董高峰 彭红明 HU Yuezhong;WANG Guangjun;DU Haibo;LIANG Sihai;LUO Yinfei;DONG Gaofeng;PENG Hongming(School of Land Science and Technology,China University of Geosciences(Beijing),Beijing 100083,China;Inner Mongolia Survey Team of Coalfield Geology Bureau,Hohhot 010010,China;School of Water Resources and Environment,China University of Geosciences(Beijing),Beijing 100083,China;Qinghai Bureau of Environmental Geology Exploration,Xining 810007,China;Key Laboratory of Environmental Geology of Qinghai Province,Xining 810007,China;Qinghai Geological Environment Protection and Disaster Prevention Engineering Yechnology Research Center,Xining 810007,China)

机构地区：[1]中国地质大学(北京)土地科学技术学院,北京100083 [2]内蒙古煤田地质局勘测队,内蒙古呼和浩特010010 [3]中国地质大学(北京)水资源与环境学院,北京100083 [4]青海省环境地质勘查局,青海西宁810007 [5]青海省环境地质重点实验室,青海西宁810007 [6]青海省地质环境保护与灾害防治工程技术研究中心,青海西宁810007

出　　处：《冰川冻土》2022年第6期1925-1934,共10页Journal of Glaciology and Geocryology

基　　金：中国科学院战略性先导科技专项(XDA20100103);青海省应用基础研究项目(2017-ZJ-743);国家自然科学基金项目(41771204)资助。

摘　　要：北麓河流域位于青藏高原腹地多年冻土区,区内受制于活动层土壤冻融过程,地表土壤含水量变化与植被覆盖关系密切。本文协同利用2018年Sentinel-1A多极化SAR与Landsat-8光学遥感时序数据,综合改进的“水云模型”、Oh模型、Dubois模型和Topp公式,完成了北麓河流域2 037.94 km2土壤含水量反演,并基于实测点土壤含水量数据验证了反演精度,回归方程Adjusted-R2为0.6848,RMSE为0.039 cm3·cm-3。从流域尺度研究土壤冻融过程、土壤含水量和植被覆盖关系的结果表明:植被覆盖对活动层冻融过程具有明显的迟滞作用,即植被覆盖度越高,活动层冻结和消融时间越滞后,该结论与前人的实地观测结果基本吻合。表明利用Sentinel-1A年度时序数据,从流域尺度研究土壤冻融过程、土壤含水量和植被覆盖的关系是可行的。Beiluhe basin lies in a permafrost region where is located in the interior of Tibetan Plateau. Ecosystem in the area is subjected to the freeze-thaw process of the active tjaele, and there is conspicuous correlation between soil moisture(SM) and vegetation coverage. To retrieve the soil moisture content of Beiluhe basin with a total area of 2 037.94 km~2, a synergistic method, which combined improved water cloud model, Oh, Dubois and Topp model, was presented in this paper base on Sentinel-1A multi-polarization SAR and Landsat-8 time series images data. The accuracy was validated with the in-situ point SM data: Adjusted-R2 of the regression equation is 0.6848, and RMSE is 0.039 cm~3·cm-3. The analysis of correlation among freeze-thaw process, SM and vegetation cover from macro watershed scale manifests: Vegetation coverage has a significant delayed effect on the freeze-thaw process of the active tjaele, that is, the higher vegetation coverage, the more lagging freezethaw time;These study results are basically consistent with predecessors in-situ observation data, verifying the feasibility of studying correlation among soil freeze-thaw process, SM, and vegetation coverage from the macro watershed scale based on Sentinel-1A annual time series data.

关 键 词：北麓河流域 多年冻土区 冻融过程 土壤含水量 植被覆盖 SAR 

分 类 号：P642.14[天文地球—工程地质学] S152.7[天文地球—地质矿产勘探]