鼎湖山4种主要森林的温度和湿度差异

Differences in Air Temperature and Moisture in Forests in Dinghushan

摘要:

利用3-5年的观测数据,分析了鼎湖山4种不同海拔高度森林温湿度的差异及其原因。结果表明:鼎湖山马尾松林、针阔叶混交林、沟谷雨林和山地常绿阔叶林的年平均气温和大气相对湿度分别为22.7℃、80%,20.9℃、82%,20.4℃、87%和19.2℃、81%。这4种森林的年平均日较差依次为5.9℃、4.6℃,3.6℃和3.1℃,且月变异系数逐渐减小,森林主要通过降低日最高温而减少林型间气温日较差。年平均湿润度计算结果表明各林型均为湿润,但月湿润度差异明显。分离综合法分析说明,局部小地形和植被类型的差异是造成林内气温在不同林型间差异的原因,而海拔高度的差异造成马尾松林与山地常绿阔叶林温度极显著差异,也加剧了与针阔叶混交林温度的显著差异。要正确评价不同森林类型改善小气候功能的强弱,必须准确区分开海拔高度、小地形、植被类型等各因素造成的差异,才能得出比较可靠的结论。

Abstract:

Based on meteorological data recorded for about 3-5 years in four forests at different elevation in Dinghushan Biosphere Reserve, the differences in forest temperature and moisture were analyzed. The results showed that the mean air temperature and relative humidity in Pinus massoniana forest, broad-leaved and coniferous mixed forest, ravine rain forest, and mountain evergreen broad-leaved forest were 22.7℃, 80%; 20.9℃, 82%; 20.4℃, 87%; and 19.2℃, 81%, respectively, while annual mean daily range of air temperatures were 5.9℃, 4.6℃, 3.6℃, and 3.1℃, respectively. The capacity of the decrease of maximum air temperature in forests was the principal factor of decreasing the annual mean differences in daily range of temperature. The moisture degree indicated that all the four forests were humid annually, but different monthly. Analysis showed that differences in temperature among the four forests were caused by the changes in micro-topography, vegetation type, and altitudinal level. To rationally evaluate the effect of various forests on microclimate, we must consider the differences caused by factors as mentioned above.