摘要
积雪是北疆地区季节冻土冻融循环的主要控制因素,季节冻土又通过改变浅层土壤的冻融相态来影响积雪融水的下渗,但该地区消融季浅层土壤的冻融状态并不清楚,致使难以从机理层面准确评估积雪和冻土协同对土壤水分的调节作用。为此,本研究基于1961—2011年阿尔泰山地区6个气象站点的积雪与冻土地面监测数据,应用高斯模型和玻尔兹曼模型进行分析,在划分多雪年、少雪年和正常年的基础上,分析了北疆地区积雪和季节冻土的基本特征,详细探讨了消融期浅层土壤的冻融状态。结果表明,该地区各站点的多年平均积雪持续期为123.2 d,多年平均最大雪深为29.7 cm;季节冻土多年平均冻结期为150.9 d,平均最大冻结深度为120.3 cm。总体上,积雪呈现增加趋势,主要表现为雪深的增加;而冻土则呈现退化趋势,主要体现在冻结期缩短和最大冻结深度减少。不同类型积雪年冻土融化结束时间和积雪消融结束时间的对比分析显示,70%的多雪年和60.5%的正常年冻土融化结束时间分别比积雪消融结束时间早8.2 d和5.5 d;而少雪年冻土融化结束时间则比积雪消融结束时间晚13.2 d。总体上,所有站点的结果表明,随着积雪的增加,消融期季节冻土处于融化状态的概率也将显著增加,积雪融水对土壤水分的补给能力增强,这将导致积雪融水在土壤中的滞留时间延长,积雪-冻土的这种协同机制将显著影响积雪融水的入渗并改变积雪水文的产汇流过程,使更多的积雪融水补给土壤,并加强融雪水与地下水的交换,有利于干旱区积雪融水的有效利用。
Snow cover is the main controlling factor of the freeze-thaw cycle of seasonally frozen ground in northern Xinjiang,and seasonally frozen ground affects the infiltration of snowmelt water by changing the freezethaw phase of shallow soil.However,the freeze-thaw state of shallow soil in the thawing snowmelt season in this region is not clear,making it difficult to accurately assess the synergistic regulation of snow cover and frozen soil on soil moisture from the mechanism level.Therefore,based on the monitoring data of snow cover and frozen ground at six meteorological stations in the Altai Mountains from 1961 to 2011,this study applied the Gaussian model and the Boltzmann model to analyze the basic characteristics of snow cover and seasonally frozen ground in northern Xinjiang on the basis of dividing high snowfall years,low snowfall years and normal years,and discussed the freeze-thaw state of shallow soil during the melting period in detail.The results show that the average duration of snow cover is 123.2 days and the average maximum depth of snow is 29.7 cm.The average annual freezing period of seasonal frozen soil is 150.9 days,and the average maximum freezing depth is 120.3 cm.In general,the snow cover showed an increasing trend,mainly manifested as an increase in snow depth.On the other hand,the frozen soil shows a degradation trend,which is mainly reflected in the shortening of the freezing period and the decrease in maximum freezing depth.The comparative analysis of the end time of the frozen soil melting and the end time of snow melt in different types of snow cover years shows that the end time of frozen soil melting in 70%snowy years and 60.5%normal years is 8.2 and 5.5 days earlier than the end time of snow melt,respectively.The end time of frozen soil melting in the year with low snowfall is 13.2 days later than the end time of snow melting.Overall,the results indicate that as snowfall increases,the probability of seasonally frozen ground being in a thawed state during the snowmelt period also increases significantly.The snowmelt water can recharge soil moisture,which leads to a longer retention time of snowmelt water in the soil.This snow-frozen soil synergistic mechanism significantly affects the infiltration of snowmelt water and alters the snow hydrology runoff process.This process can facilitate more snowmelt water replenishing the soil and strengthens the exchange between meltwater and groundwater,contributing to the effective utilization of snowmelt water in arid regions.
作者
张晓慧
汤萃文
张伟
沈永平
贺斌
毛炜峄
ZHANG Xiaohui;TANG Cuiwen;ZHANG Wei;SHEN Yongping;HE Bin;MAO Weiyi(School of Environmental and Municipal Engineering,Lanzhou Jiaotong University,Lanzhou 730070,China;State Key Laboratory of Cryospheric Science and Frozen Soil Engineering,Northwest Institute of Eco-Environment and Resources,Chinese Academy of Sciences,Lanzhou 730000,China;Altay Hydrological Survey and Measurement Center,Altay 836500,Xinjiang,China;Institute of Desert Meteorology,China Meteorological Administration,Urumqi 830002,China)
出处
《冰川冻土》
2025年第1期71-84,共14页
Journal of Glaciology and Geocryology
基金
国家自然科学基金项目(42471162)
国家重点研发计划中蒙国际合作项目(2024YFE0113200)
新疆维吾尔自治区重点研发任务专项(2022B03021-1)资助。
关键词
北疆阿尔泰山
积雪融水
季节冻土
冻融状态
土壤水分
Altai Mountains in northern Xinjiang
snowmelt water
seasonally frozen ground
freeze-thaw state
soil moisture
