摘要
[目的]分析常见园林树种叶片表面的微形态结构、吸附颗粒物的粒径分布及滞留重金属能力,为选择和配置园林树种以改善我国空气环境质量提供科学依据。[方法]对垂柳(Salix babylonica)、油松(Pinus tabulaeformis)、紫叶李(Prunus cerasifea)、榆树(Ulmus pumila)、紫荆(Cercis racemosa)、国槐(Sophora japonica)、银杏(Ginkgo bi-loba)、大叶黄杨(Euonymus japonicus)和白蜡(Fraxinus americana)9个园林树种的叶片进行低温冷冻干燥处理后,采用扫描电镜扫描其表面及滞留颗粒物的形态,以能谱仪测定叶片表面滞留的重金属成分,分析叶片表面微形态结构与滞留颗粒物的关系。[结果]在北京市六郎庄桥区域,大气中的颗粒物主要附着在绿化带园林树种叶片上表面,且以吸附可吸入颗粒物(PM10)为主;不同园林树种单位叶面积滞留大气颗粒物总数排序为大叶黄杨>白蜡>紫荆>国槐>油松>银杏>榆树>垂柳>紫叶李;银杏、紫荆和油松叶片表面具有较深且宽的沟槽,大叶黄杨和白蜡叶片表面具有蜡质结构,国槐叶片上表面具有较浅的波浪状突起和较短而稀疏分布的表皮毛,有利于大气颗粒物滞留;除紫荆和油松外,其他树种叶片上表面滞留细颗粒物(PM2.5)的能力明显高于下表面;9个树种叶片上表面的PM2.5/PM10平均值高于下表面。各树种叶片上表面吸附铝、铜、锌、砷和镉等重金属元素较多,吸附钛、铬、镍和铅等重金属元素较少。相关性分析结果表明,叶片表面滞留的锌含量与铜和砷含量呈显著正相关(P<0.05)。[结论]银杏、紫荆和油松叶片表面具有大量较深且宽的沟槽,大叶黄杨和白蜡叶片表面具有蜡质结构,国槐叶片上表面具有较浅的波浪状突起和较短而稀疏分布的表皮毛,均有利于吸附大气颗粒物,可作为滞尘能力较强的绿化树种选用。
【Objective】In order to provide a scientific basis for selecting and arranging garden trees to improve quality of air environment in China,some typical garden tree species were applied in the current study,where the analysis of relationships among the fine structures of leaf surface,the diameter range of absorptive particles and the remaining amount of mental particles were made.【Method】Salix babylonica,Pinus tabulaeformis,Prunus cerasifea,Ulmus pumila,Cercis racemosa,Sophora japonica,Ginkgo biloba,Euonymus japonicus and Fraxinus americana were used as materials. The leaves of nine tree species were subjected to freeze-drying treatment. Scanning electron microscopy was used to scan the surface of the leaves and the morphology of the retained particles. The heavy metal components retained on the surface of the leaves were measured by energy spectrometer. The relationship between the micro-structure of the leaf surface and particles matter that remained on freeze dried leaves was analyzed.【Result】The atmospheric particles mainly adhered to the upper surface of plant leaves,and were mainly inhalable particulate matter(PM10)in Liulangzhuangqiao,Beijing. The capability of different garden tree species to retain the total number of particles per leaf unit are sorted in order: E. japonicu> F. americana>C. racemosa>S. japonica>P. tabulaeform>G. biloba>U. pumila>S. babylonica>P. cerasifea. The surface of the leaf had deep and wide groove in G. biloba,C. racemosa and P. tabulaeform. E. japonicu and F. americana had waxy structure on the leaf surface. For S. japonica,the narrow groove on the surface of the leaf and the densely distributed short epidermal structure were conducive to the retention of atmospheric particles. Except for C. racemosa and P. tabulaeformis, the ability of other species to retain fine particulate matter(PM2.5)on the upper surface of the leaves was significantly higher than that of the lower surface. The average value of PM2.5 /PM10 was characterized by the upper surface of the leaf being h
作者
高海波
GAO Hai-bo(College of Life Science,Linyi University,Linyi,Shandong 276000,China)
出处
《南方农业学报》
CAS
CSCD
北大核心
2019年第5期1035-1041,共7页
Journal of Southern Agriculture
基金
山东省自然科学基金项目(ZR2014CL030)
临沂大学博士科研启动基金项目(LYDX2013BS036)
关键词
园林树种
叶表面
可吸入颗粒物
重金属
能谱仪
garden tree species
leaf surface
inhalable particulate matter
heavy metal
energy spectrometer
