热带季节雨林林窗边缘不同热力作用面热力效应的季节变化特征

Characteristics of thermal effects and seasonal variation on different thermal active surfaces of canopy gaps in tropical seasonal rain forest

通过对热带季节雨林雾凉季和湿热季昼间林窗区域不同热力作用面的热力效应初步分析 ,指出在西双版纳 ,不论是雾凉季还是湿热季 ,热带季节雨林林窗边缘壁面均具有不可忽视的热力作用 ,且由于受林缘树木的影响 ,热力效应较强的东侧、北侧林缘壁面最大区域出现位置高于次生林林窗 ,而强度小于次生林林窗。显示了林窗边缘壁面的热力效应除与太阳高度角、太阳辐射的时间长短和强度有关之外 ,林窗边缘树木高度也是不可忽视的因子。其结果可为进一步研究林窗小气候形成机制提供研究基础 。

Based on the analyses of daytime thermal effects of different thermal active surfaces in canopy gaps in tropical seasonal rain forest in the cool fog and hot wet season in Xishuangbanna, the thermal characteristics of different thermal active surfaces in canopy gaps are described. The finding showed that: The thermal effect of vertical thermal active surfaces is not negligent, not only in the cool fog season, but also in the hot wet season. Moreover, influenced by the height of trees that form the edge of the gap, the height of maximum area of thermal effect of vertical thermal active surfaces at the east and north edge of gaps in tropical seasonal rain forest was higher than that in secondary forest, but the intensity of thermal effects was weaker, compared to secondary forest. This indicates that, besides solar angle, time and intensity of radiation, the height of trees is also an important factor that influences thermal effects of vertical thermal active surface of edges. The results supply a research basis for understanding microclimatic formation of canopy gaps, for studying forest succession and effects of forest biodiversity.