黄河上游地区辐射收支及土壤热状况季节变化特征  

THE SEASONAL VARIATION CHARACTER OF RADIATION BUDGET AND SOIL HEAT CONDITION IN THE UPPER YELLOW RIVER

作　　者：李锁锁[1] 吕世华[1] 奥银焕[1] 尚伦宇[1] 

机构地区：[1]中国科学院寒区旱区环境与工程研究所西部气候环境与灾害实验室,兰州730000

出　　处：《太阳能学报》2009年第2期156-162,共7页Acta Energiae Solaris Sinica

基　　金：国家自然科学基金项目(40575032);国家重点基础研究发展计划项目(2005CB422003)

摘　　要：利用"玛曲气候与环境综合观测研究站"2006年7月～2007年5月的观测资料,分析研究了黄河上游地区辐射及土壤热状况年变化特征。结果表明:该地区各辐射分量均存在显著的季节变化,4～9月份显著增加,10月份～来年3月份明显降低,年变化呈典型的单峰结构。地表反照率除冬季降雪期外,季节变化不是很明显,年平均地表反照率约为0.26;其日变化与太阳高度角关系密切。一年中,土壤温度梯度1月份最大,4月份最小。土壤温度梯度和净辐射相关系数为-0.61,通过了0.01的置信度检验。2.5～30cm浅层土壤热通量振荡明显,而30cm以下深层土壤热通量变化缓慢,10月份～次年5月份日平均土壤热通量从地表以下2.5～75cm土壤层几乎均为负值,说明更深层土壤释放热量,上层的土壤吸收热量;而其余月份则为正,土壤热量从浅层向深层传导。冬季由于土壤含冰量的影响,土壤导热率在1月份最大,而3、4月份相对较小;季节平均土壤导热率分别为:春季0.27、夏季0.38、秋季0.55、冬季0.83W·(m·K)^(-1)。Using the data observed in Maqu station from July, 2006 to May, 2007 the character of the surface radiation budget and soil heat condition in upper Yellow River were analyzed. The results show that the seasonal variations of each radiation component are obvious： increasing in summer and reducing in winter. The annual variation has one extremum. The seasonal variation of surface reflectivity isn＇ t obvious, the annual average reflectivity is 0.26; the daily variation is relative to solar altitudinal angle. Soil temperature gradient is maximum in January and minimum in April all the year round. The correlative coefficient between soil temperature and net radiation is -0.61, confidences test reaches 0.01. The soil heat flux obviously fluctuated in the shallow soil layer and slowly in the deep layer. The soil heat flux is negative 2.5 to 75cm under surface from Oct. to the next May. It indicated that the deeper soil layer released heat flux and the upper soil layer absorbed heat flux, and the other month reversed. Because of ice content in soil, the thermal conductivi- ty is maximum in Jan. and minimum in March and April; The seasonal average thermal conductivity is 0.27, 0.38, 0. 55 and 0.83W·（m·K）-1 in every season, respectively.

关 键 词：黄河上游 辐射收支 地表反照率 土壤温度梯度 土壤导热率 

分 类 号：TK512.4[动力工程及工程热物理—热能工程]