热带次生林、季雨林林窗温度特征对比分析

A Comparison on Temperature CharacteristicsBetween Tropical Secondary Forest and Seasonal Rain Forest Gaps

以西双版纳热带次生林和季雨林林窗为研究对象,以实际观测为基础,对比分析了两林窗温度的时空分布特征及变化规律.结果表明:两林窗气温昼间变化均为单峰型,气地温差的林窗间差异说明不同林窗的林地热力作用面存在热的"源""汇"转换效应,即使是同一林窗不同季节的不同时间段也呈现热的"源""汇"转换现象,增加了林窗环境的异质性;两林窗平均温度时间变化与空间分布基本相似,温度高值区均存在随时间和季节动态位移的现象,就整个时空分布态势而言,很大程度受制于林窗的形状,呈现沿林窗主轴线排布的现象.这种时间变化和空间分布规律可能会影响不同时期物种的入侵、定居、繁殖,进而影响林窗物种的组成.

The temporal-spatial dynamics of temperature in tropical secondary forest and seasonal rain canopy gaps in Xishuangbanna are analyzed .The results show as follows:Temporal variations of temperature follow with single peak in both gaps.The difference of temperature between air and surface shows that there is thermal source-sink switching effect on the thermal acting interface in the gaps,even if in the same gap at different season,which build up the environmental heterogeneity of the gaps.The temporal-spatial dynamics of the temperature in both gaps are near the same,which shows that the points of maximum temperature shift along with time and season,and the temporal-spatial dynamics are restricted by the shape of gap,lining the main axis of gap.This phenomenon may affect the invasion,colonist and reproduce of species,and further influence the species composition in forest.