黄河源区冻土水文关键要素变化过程及特征分析  

Variation and characteristics of soil hydrological elements in the source region of the Yellow River

作　　者：施发祥 秦甲 韩添丁 孙洋 杨冰峰 付晓雷 游艳辉 SHI Faxiang;QIN Jia;HAN Tianding;SUN Yang;YANG Bingfeng;FU Xiaolei;YOU Yanhui(State Key Laboratory of Cryospheric Science,Northwest Institute of Eco-Environment and Resources,CAS,Lanzhou 730000,China;State Key Laboratory of Frozen Soil Engineering,Northwest Institute of Eco-Environment and Resources,CAS,Lanzhou 730000,China;University of Chinese Academy of Sciences,Beijing 100049,China;Jiangxi University of Finance and Economics,Nanchang 330013,China;Lanzhou University of Technology,Lanzhou 730050,China;Yangzhou University,Yangzhou 225009,Jiangsu,China)

机构地区：[1]中国科学院西北生态环境资源研究院,冰冻圈科学国家重点实验室,兰州730000 [2]中国科学院西北生态环境资源研究院,冻土工程国家重点实验室,兰州730000 [3]中国科学院大学,北京100049 [4]江西财经大学,南昌330013 [5]兰州理工大学,兰州730050 [6]扬州大学,江苏扬州225009

出　　处：《地理科学进展》2023年第9期1691-1703,共13页Progress in Geography

基　　金：国家重点研发计划课题(2021YFC3201102);国家自然科学基金项目(42171028);冻土工程国家重点实验室开放基金(SKLFSE202110);河海大学水灾害防御全国重点实验室“一带一路”水与可持续发展科技基金项目(2021490611)。

摘　　要：冻土水文要素变化及关键参数的确定是黄河源区水文过程分析和模型模拟研究的核心内容之一。为进一步认识冻土冻融影响下黄河源区冻土水文关键要素变化及特征,论文选取玛曲季节冻土观测站和康穷多年冻土观测站进行对比分析,结合降水、蒸散发、冻土土壤水分的野外观测,采用HYDRUS-1D模型冻融模块进行模拟分析。结果表明:(1)冻土冻融过程会改变土壤水力参数,季节冻土饱和含水率θs冷季大于暖季,残余含水率θr冷季小于暖季;多年冻土饱和含水率θs冷季大于暖季,残余含水率θr仅深层冷季小于暖季。(2)季节冻土与多年冻土在年内冻结期间土壤含水量呈“U”形变化;在冻结稳定时期季节冻土储水量减少比多年冻土快。(3)冻结稳定时期季节冻土与多年冻土底部渗漏通量都不断减少,而多年冻土由于底部冻土层的存在,底部渗漏通量减少到0后保持不变。(4)季节冻土与多年冻土在地下20 cm处存在冻结锋面,冻结开始期间土壤水双向流向冻结锋面,融化开始期间土壤水由冻结锋面双向流出。研究对于深化黄河源区冻土水文过程的认识,优化水资源管理具有重要的理论和实际价值。Hydrological element variation analysis and key parameter identification are one of the core contents of the research on hydrological processes and model simulation in the source region of the Yellow River.In order to understand the influence of freeze-thaw action on soil hydrological elements in the source region of the Yellow River,this study compared the data from the MQ seasonally frozen soil observatory and the KQ permafrost observatory.Based on the data of field monitoring,variability of soil hydrological elements was examined and simulated by the freeze-thaw module of the HYDRUS-1D software.The results showed that:1)The freeze-thaw process of soil leads to changes of soil hydrological elements.The saturated soil moisture(θs)of seasonally frozen soil is higher during cold period than warm period,the residual soil moisture(θr)is the opposite.For permafrost,θs during cold period is higher than warm period,θr during cold period is lower than warm period in the deep layer only.2)The soil water content of both seasonally frozen soil and permafrost shows a U-shaped change during freezing within the year,and the water storage of seasonally frozen soil decreases faster than permafrost during the rapid freezing period.3)The bottom leakage flux of seasonally frozen soil and permafrost both decreases continuously during the stable frozen period,while the bottom leakage flux of permafrost decreases to 0 because of the baseplate of permafrost active layer,and remains unchanged.4)The frozen peak point of both seasonally frozen soil and permafrost exists at 20 cm below soil surface.Soil water flows bilaterally to the frozen peak point during the rapid freezing period,and flows bilaterally out from the frozen peak point during the rapid thawing period.This study has important theoretical and practical value for understanding of the hydrological process of frozen soil more profoundly and optimizing the management of water resources in the source region of the Yellow River.

关 键 词：冻土水文要素 土壤水力参数 季节冻土 多年冻土 黄河源区 

分 类 号：P642.14[天文地球—工程地质学]