春秋季节侧柏-山毛桃群落演替初期的小气候特征

Spring and Autumn Microclimate Characteristics of Platycladus Orientalis and Prunus Davidiana Mixed Forest in Early Succession Stage

开展森林小气候研究,对于协调生物与环境的关系、保护生物多样性以及实现森林的可持续高效管理,都是十分重要的。选择5月和10月典型的晴朗无风天气条件,以侧柏纯林为对照,研究了郁闭度为0.25、0.54和0.87的侧柏-山毛桃群落演替初期小气候特征。结果表明,侧柏-山毛桃混交林对春季和秋季林内空气温度的早间增温效应和午间降温效应,随着郁闭度增加而增大。春季的高温峰值出现在15时,晚于秋季的高温峰值13时。春季和秋季林内10 cm处地温日间呈持续增加趋势,春季以郁闭度为0.25的B点为最高,秋季侧柏纯林在12时前为最低,14时后为最高。春季林内空气相对湿度从07时到11时呈快速降低的趋势,然后逐渐缓慢回升;而秋季林内的相对湿度,随着郁闭度的增加而增大,但日间变化幅度比较小。无论春季还是秋季,侧柏和山毛桃的叶片温度日间变化均呈先升高后缓慢降低的趋势。春季郁闭度对侧柏和山毛桃的叶片温度影响不显著,但秋季11-15时,随着郁闭度的增加,叶片温度有降低的趋势。在太行山区,以山毛桃为保护树种,快速提高侧柏-山毛桃混交林的郁闭度,对有效地改善林内小气候,促进森林更新和管理都是十分重要的。

Micrometeorological research is vital to harmonize the relationship between plant and environment, protect biodiversity and sustainable manage forest. We researched on microclimate characteristics of P. orientalis and P. davidiana mixed forest in early succession stage at three canopy density level （0.25, 0. 54 and 0. 87, separately） in typal sunny windless weather of May and October on Mt Taihang, Henan, China, with the P. orientalis m effect of air temperatures cooling in the morning canopy density increa arose in 15 o＇ clock, onop and lantation as a control. The results showed that the warming in the afternoon became greater with the sing in the mixed forest at spring and autumn. which was later than 13 o＇ clock at autumn. The peak of air temperature at spring Soil temperatures at 10 cm depth continually increased in the daytime at spring and autumn. At spring, the highest soil temperature was in 0.25 canopy density of B site, and at autumn, monoplantation site recorded the lowest soil temperature before 12 o＇ clock and the highest after 14 o＇ clock. At spring, relative humidity fleetly reduced from 7- 11 o＇ clock, and then gradually recovered. At autumn, relative humidity increased with the canopy density increasing, but the diurnal variety range was small. Diurnal leaf temperature variety was generally increasing and then falling both at spring and autumn. The effect of canopy density on leaf temperature was not significant at spring, but between 11--15 o＇ clock at autumn, leaf temperature reduced with canopy density increasing. In Mt. Taihang area, it is important to speed a closed-canopy performance of P. orientalis and P. davidiana mixed forest by using P. davidiana and facilitating forest regeneration and management as a nurse species for ameliorating microclimate