中文摘要：

通过藏东南色季拉山急尖长苞冷杉林典型林隙与非林隙的旷地和林内小气候观测,从昼间总辐射、气温、相对湿度、地表温度和5-15 cm层土壤温度指标,分析夏季林隙与非林隙小气候的异同。结果表明,冷杉林林隙总辐射年变化呈双峰曲线,峰值分别出现在5和8月;林隙总辐射的日变幅和年变幅均小于旷地,年总辐射量为1 173.28 MJ/m2,总辐射量显著低于旷地（P〈0.01）。夏季昼间,林隙与非林隙气温变化曲线均呈倒S型,林隙气温日变幅小,介于旷地与林内之间,接近林内而低于旷地;林隙相对湿度高于旷地和林内,且日变幅较小。林隙和非林隙的地表温度日变化趋势与气温基本一致,旷地地表及土壤各层温度显著高于林隙和林内;土壤温度随土层深度增加而递减,10 cm及以下土层无明显日变化;地表温度受夏季太阳辐射影响,其日变幅显著高于土壤温度。

英文摘要：

Through the microclimate observation of gaps and non-gaps（ under-canopy and open spaces） of Abies georgei forest in the Sejila Mountain,southeastern Tibet,we monitored daytime total radiation,air temperature,relative humidity,surface temperature and 5- 15 cm layer soil temperature,and analyzed the similarities and differences of microclimate between forest gaps and non-gaps in summer time. The results showed that,the annual change of total solar radiation to fir gaps presented bimodal curve and the peak values appeared in May and August. The diurnal and annual variation ranges of total solar radiation in forest gaps were less than that of open spaces,and meanwhile,the annual total solar radiation of gaps was 1 173. 28 MJ / m2,which was significantly lower than that of the open spaces（ P 〈 0. 01）. The changing curves of air temperature in gaps and non-gaps during summer daytime were of inverted S,and the diurnal variation range of air temperature in gaps was small,ranging between open spaces and undercanopy,and it was closed to that in under-canopy and significantly lower than that in the open spaces.The relative humidity of gaps was higher than that of open spaces and under-canopy,meanwhile the variation range of it was small. The diurnal variation trend of surface temperature in forest gaps and nongap was basically consistent with the change of air temperature. The temperatures of land surface and soil layers in open spaces were significantly higher than that in gaps and under-canopy. The soil temperature decreased with the increase of soil depth,and there was no obvious diurnal variation under 10 cm layer.Due to the influence of solar radiation to the surface temperature,the diurnal variation amplitude of it was much higher than that of the soil temperature.