城市公园木本植物群落的叶面积指数与辐射消减效应  

Leaf area index and radiation attenuation effects of woody plant communities in urban park

作　　者：李佩瑗 胡砚秋[2] 张璐[1] 苏志尧[1] 王祥林[2] 

机构地区：[1]华南农业大学林学院,广东广州510642 [2]江门市园林局,广东江门529040

出　　处：《中南林业科技大学学报》2015年第3期78-83,共6页Journal of Central South University of Forestry & Technology

基　　金：广东省林业科技创新项目(2011KJCX031-02);江门市科技计划项目(2010)

摘　　要：木本植物群落具有遮阴和辐射消减的功能,可以缓解城市夏季的热岛效应。为定量研究城市公园木本植物群落的辐射消减效应,选择江门市城区公园24个木本植物景观单元,采用半球面影像技术获取林冠影像,分析模拟城市公园植被冠层结构和林下光照条件。结果表明：1）江门城区公园木本植物景观单元的叶面积指数（ILAI）处于0.88-2.22之间,低于自然环境植被IN,LAI水平;2）冠层对光照的辐射消减率随ILAI的增加而增大,ILAI与直射光消减率和散射光消减率均呈极显著正相关;3）城区公园树木景观单元林冠下直射光的变异程度强于林下散射光,林冠对直射光的影响大于散射光;4）城市公园林冠对直射光和散射光的消减作用极显著,月际变化呈单峰分布,以6-8月消减量最大。Woody plants have the functions of shading and radiation attenuation, can mitigate the urban heat island effect. To quantitatively study radiation attenuation effect of wo ody plant community in urban park, twenty four treescapes in Jiangmen city urban park were selected, then their tree crown images were extracted by adopting hemispherical photography technology, and The canopy stru cture and understory light conditions in the sample plots were simulated and analyzed. The results show that（1） The ILAI value of treescapes in Jiangmen urban park（0.88 - 2.22） was lower than the I N,LAI under natural vegetation;（2） The radiation attenuation rate of the canopy to illumination increased with the increase of ILAI, ILAI values were significantly positively correlated with attenuation rate of direct and diffuse solar radiation;（3） The variability of transmitted direct solar radiation was greater than transmitted diffuse solar radiation, and canopy had more influences on direct light than diffuse light;（4） The attenuation effects of canopy on both direct and diffuse solar radiation were significant, The monthly variations of attenuation effects displayed a single peak distribution and reached the maximum in June t o August.

关 键 词：城市公园木本植物 叶面积指数 辐射消减效应 半球面影像技术 植被冠层结构 林下光照条件 

分 类 号：S718.51[农业科学—林学]