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利用2009—2011年塔克拉玛干沙漠大气环境观测试验站测得的土壤热通量数据,分析了塔克拉玛干沙漠腹地土壤热通量在不同天气条件下的变化特征。结果表明:(1)塔克拉玛干沙漠腹地1cm处土壤热通量年平均值为1.9 W·m~(-2),5、20、40cm处分别为1.0、0.4、0.4 W·m~(-2);1cm处土壤热通量年最大值为334.1 W·m2,年最小值为-184.2 W·m~(-2);土壤热通量基本表现为夏季>春季>秋季>冬季。(2)各土层土壤热通量具有明显的日变化特征。随着土壤深度的加大,土壤热通量的日变化幅度明显减小,最大值出现的时间有一定的滞后性。土壤热通量5cm出现最大值的时间比1cm处延迟3h,延迟速率为0.75h·cm-1,20cm比5cm出现最大值的时间晚2h,延迟速率约为0.13h·cm-1。(3)不同天气情况下的土壤热通量日变化特征有一定的差异,晴天较为规则,阴天、雨天、沙尘天则较不规则,且1cm处土壤热通量受天气影响最显著。晴天1cm处土壤热通量平均值为9.0 W·m~(-2);阴天、雨天、沙尘天1cm处土壤热通量值平均值分别为5.1、-6.1、-1.9 W·m~(-2)。
Based on the soil heat flux data measured in the Taklimakan Desert Atmospheric Environment Observation and Test Station in 2009-2011, the change characteristics of soil heat fluxes in the hinterland of Taklamakan Desert under different weather conditions were analyzed. The results showed that: (1) The average annual soil heat flux at 1 cm in the hinterland of Taklamakan Desert was 1.9 W · m -2 (1.0,0.4,0.4 W · m -2) ; The maximum annual soil heat flux at 1 cm was 334.1 W · m 2, and the annual minimum was -184.2 W · m -2. The soil heat flux basically manifested as summer> spring> autumn> winter. (2) Soil heat flux in each soil layer has obvious diurnal variation characteristics. With the increase of soil depth, the diurnal variation of soil heat flux obviously decreases and the time of maximum appears some lag. Soil heat flux 5cm maximum time than the 1cm delay 3h, the delay rate of 0.75hcm-1, 20cm 5cm later than the maximum time appears 2h, the delay rate of about 0.13h cm-1. (3) The diurnal variation of soil heat fluxes under different weather conditions are different, sunny days are more regular, cloudy days, rainy days and dust days are more irregular, and the soil heat flux at 1cm is most affected by the weather. The mean value of soil heat flux at 1 cm in sunny day was 9.0 W · m -2. The mean values of soil heat flux at 1 cm above the dusty day were 5.1, -6.1 and -1.9 W · m ~ (-2).