沈阳城市森林小气候特征的研究

Microclimate characters of urban forest in Shenyang City.

研究了沈阳城市森林不同生长期小气候温湿日变化特征.结果表明,城市森林不同生长期气温日变化趋势是早晨气温最低、午后气温最高,但受森林生态环境的影响,最高峰比太阳辐射峰值迟滞约2 h.一年四季气温日变幅为森林停止生长期(休眠期)>生长季前期>生长季后期>生长季中期.森林生长季前期、中期、后期土壤温度为白天高于夜间,而停止生长期(休眠期)为夜间高于白天.不同生长期土温日振幅为上层(20 cm)>中层(40 cm)>下层(80 cm),而同一层不同生长期的土温日振幅为土层深20 cm时,生长季前期>生长季后期>停止生长期(休眠期)>生长季中期;土层深>40 cm(80 cm)时,生长季前期>停止生长期(休眠期)>生长季后期>生长季中期.城市森林空气相对湿度日变化与气温和地温日变化则夜间的空气相对湿度高于白天,但不同生长期相对湿度值日变化为生长季中期>生长季后期>停止生长期(休眠期)>生长季前期.

This paper analyzed the diurnal changes of the temperature and humidity in Shenyang urban forest during its different growth stages. The results showed that air temperature was the lowest in the morning and the highest at noon. The highest peak point of air temperature lagged behind that of solar radiation about 2 hours, due to the influence of forest environment. The annual air temperature amplitude was in order of stop-growth period （dormancy stage） （DS） 〉 prophase of growth season （PGS） 〉 anaphase of growth season （AGS） 〉 medium-term of growth season （MGS）. Soil temperature of PGS, MGS and AGS at daytime was higher than that at night, while that of DS was in reverse. The daily soil temperature amplitude at different growth stages was in order of upper soil layer （20 cm） 〉 medium soil layer （40 cm） 〉 lower soil layer（80 cm）, while the diurnal soil temperature amplitude in the same soil layer was in order of PGS〉 AGS〉DS〉 MGS （20 cm） and PGS〉 DS〉 AGS〉 MGS （80 cm）. The diurnal change of relative humidity was reverse to that of air- and soil temperature, which was higher at night than at daytime, and was in order of MGS 〉 AGS〉 DS 〉 PGS.