吉林地区不同林型降温效果的比较研究

Comparative study of cooling effect of different forest types in Jilin region

以吉林市及周边地区的城市森林为对象，应用对比观测法研究不同森林类型的降温效果，结果表明：不同树种构成的森林类型降温效果存在显著差异；影响降温的因子随着时间的变化而变化，一般情况下，8：00～10：00、10：00～12：00、12：00～14：00等时间段，只有不同树种构成的纯林对降温的影响极显著，其中，长白落叶松林的降温效果最好，北美短叶松林、榆林等降温效果一般，而毛果绣线菊灌丛、蒙古栎林、连翘灌丛等的降温效果较差；混交林降温效果因树种组成不同，差异较大，长白落叶松＋糠椴＋山杨林好于糠椴＋蒙古栎林和黑桦＋蒙古栎林。

Cooling effects of different forest types were researched by comparative observation method in Jilin City and adja -cent areas, results indicated that there were significant differences among the cooling effects of different forest types .Influ-ence factor for cooling was changed with the variation of time .Under normal circumstances , pure forest significantly was in-fluenced by cooling from 8：00 to 10：00, 10：00 to12：00,or from 12：00 to 14：00, showing that Larix olgensis Henry forest presented best cooling effect .The effects of Pinus banksiana Lamb and Ulmus pumila L.forest were common .The effects of Spiraea trichocarpa Nakai bushwood , Quercus mongolica Fisch forest and Forsythia suspensa bushwood were worse .Cool-ing effect of mingled forest was varied with different species composition , the cooling effects of Larix olgensis Henry＋Tilia mandsburica ＋Populus davidiana forest was better than Tilia mandsburica Rupr＋Quercus mongolica Fisch forest and Betu-la dahurica Pall.＋Quercus mongolica Fisch forest.