为了研究青藏高原暖季土壤水分对冻土区地表热状况的影响,选取2010-2012年5-9月在青藏高原唐古拉气象场获取的气象及其活动层数据,分析了表层土壤水分对地表反照率以及土壤热参数的影响.结果表明:唐古拉站暖季表层土壤含水量集中在0.15~0.27之间,地表反照率值集中在0.14~0.24之间,日平均土壤热导率的波动范围在0.9~2.0 W·m^-1·K^-1之间,土壤热容的波动范围主要集中在0.8×10~6~1.8×10~6J·m^-3·K^-1之间,而土壤热扩散率则主要集中在0.6×10~(-6)~2.2×10~(-6)m~2·s^-1之间.土壤水分对地表反照率影响较大,随着土壤水分的增长,地表反照率呈现出明显的减小趋势.土壤水分对地表反照率的影响还受到植被生长周期的影响,土壤水分和地表反照率之间的关系在植被枯萎期和生长期有明显的差异性.唐古拉地区土壤热参数也明显受到土壤水分变化的影响,随着土壤水分的增加,土壤热导率、热容和热扩散率都为增大趋势,但是土壤水分对土壤热导率的影响较为显著,而对土壤热扩散率的影响则不显著.
In order to study the effects of soil moisture on surface thermal state of permafrost in warm season on the Tibetan Plateau,meteorological and active layer data during May and September from 2010 to 2012 in Tang-gula meteorological field on the Qinghai-Tibetan Plateau were selected for analyzing the relationship between the surface soil moisture and surface albedo well as the soil thermal parameters. The results show that the soil mois-ture were between 0. 15 and 0. 27,surface albedo values were between0. 14 and 0. 24,daily average soil ther-mal conductivity were 0. 9~2. 0 W · m-1 · K-1,the soil heat capacity mainly concentrated between the 0. 8 × 106 and 1. 8×106 J · m-3 · K-1 ,and soil thermal diffusivity was mainly concentrated between the 0. 6 × 10-6 and 2. 2 × 10-6 m2 · s-1 in the warm season of the Tanggula station. The effect of soil moisture on surface albedo was great,with the increase of soil moisture,and the surface albedo shows a clear increasing trend. The effect of soil moisture on the surface albedo was also affected by the vegetation growth cycle,the relationship between soil moisture and surface albedo were significantly different between the withered and the growth periods. Soil ther-mal parameters was also influenced significantly by the changes of soil moisture,with the increase of soil mois-ture,soil thermal conductivity,heat capacity and thermal diffusivity also showed increasing trend,but the effect of soil moisture on soil thermal conductivity was significant,while the influence on soil thermal diffusivity was not significant.