森林公园林分结构特征对空间热环境的影响

Influence of forest park stand structure characteristics on spatial thermal environment

通过对野外标准地实测与分析获取森林公园林分结构特征和温度的相关信息,研究林分非空间结构特征与林分空间结构特征对热环境的影响.结果表明:林分非空间结构及空间结构特征对空间热环境模型的影响占比分别为66.25%、33.75%.林分非空间结构中的郁闭度、树高、枝下高对空间热环境的影响最显著,而胸径、林分胸高断面积、植株密度对空间热环境的影响不显著.郁闭度与气温呈线性负相关,树高、枝下高与空间热环境存在显著正相关,郁闭度每增加0.1,空气温度降低0.4℃;而树高每增加0.1 m,温度增加0.013℃;枝下高每增加0.1 m,温度增加0.017℃.空间结构特征中混交度与空间热环境呈正相关,混交度每增加0.1,温度增加0.19℃;开阔比与空间热环境呈负相关关系,开阔比每增加0.1,温度下降0.22℃.

To investigate the function of forest park on regulating urban climate,5 spatial structure indexes(i.e.:dominance,open comparison,Mingling degree,competition index,uniform angle index)and 7 non-spatial structure indexes were analyzed at 11 sampling plots across Sanming Golden Bay Forest Park.And temperature was monitored every 10 minutes for 2 min between 11:30-12:30 in August.Then Pearson analysis and model test were conducted to evaluate relationships between different indexes and their contribution to forest temperature.The results showed that the influence of non-spatial structure and spatial structure for forest on spatial thermal environment model was 66.25%and 33.75%,respectively.Canopy density,tree height,branch height had significant impacts on the spatial thermal environment,while DBH,forest chest high cross-sectional area and plant density did not influence the spatial thermal environment significantly.Canopy density was linearly negatively correlated with temperature,while tree height and branch height were significantly positively correlated with spatial thermal environment.For every 0.1 increment of canopy density,air temperature decreased by 0.4℃and for every 0.1 increment of Mingling degree,air temperature increased by 0.19℃.The open comparison was negatively correlated with space thermal environment,namely for every 0.1 increment of open comparison,air temperature decreased by 0.22℃.