| 北京不同污染地区园林植物对空气颗粒物的滞纳能力 |
| 摘要点击 2193 全文点击 1273 投稿时间：2014-11-22 修订日期：2015-01-04 |
| 查看HTML全文
查看全文 查看/发表评论 下载PDF阅读器 |
| 中文关键词 植物园 五环路 园林植物 颗粒物 滞纳能力 叶片结构 |
| 英文关键词 botanical garden the 5th Ring Road landscape plants particulate matter adsorption capacity the leaf microstructure morphology |
|
| 中文摘要 |
| 城市园林植物作为城市生态系统的重要组成成分,在滞纳空气颗粒物,净化城市大气环境发挥着重要作用. 本文以北京市6种常见园林植物为研究对象,利用气溶胶再发生器(QRJZFSQ-I)测定了不同污染地区叶片对大气颗粒物的滞纳能力,同时利用环境扫描电镜观察了测试树种叶片结构变化. 结果表明:①在所测的树种中,针叶树种单位叶面积滞纳空气颗粒物的能力比阔叶树种高,其中油松(Pinus tabuliformis)滞纳量最高,为(3.89±0.026) μg ·cm-2,其次是白皮松(Pinus bungeana),为(2.82±0.392) μg ·cm-2,毛白杨 (Populus tomentosa)最小,为(2.00±0.118) μg ·cm-2; ②通过观察叶片微观形态结构发现,针叶树种气孔排列紧密,气孔密度比阔叶树种大,表面粗糙度高于阔叶树种,而且能够分泌油脂; ③在不同污染区,相同树种叶片滞纳PM10存在显著差异,五环周围的树种叶片单位叶面积滞纳PM10能力要高于植物园的,而相同树种叶片单位叶面积滞纳PM2.5则无明显差异; ④在不同污染区下,叶片结构发生了重要的适应性变化,相对于轻污染区,在重污染区植物叶片外表皮细胞收缩,叶片表皮纹理变得更加粗糙,气孔频度和绒毛长度增加. 尽管暴露于重污染区植物叶片发生重要变化,但是这些植物仍然能够正常健康地生长. |
| 英文摘要 |
| Urban landscape plants, as one of the important factors of the urban ecosystem, play an important role in stagnating airborne particulates and purifying urban atmospheric environment. In this article, six kinds of common garden plants were studied, and aerosol generator (QRJZFSQ-I) was used to measure the ability of their leaves to stagnate atmospheric particulates (TSP and PM2.5) in different polluted regions. Meanwhile, environmental scanning electron microscope was used to observe changes in the leaf structure of the tested tree species. The results showed: ①Among the tested tree species, the ability of coniferous species to stagnate atmospheric particulates was higher than that of broad-leaved species per unit leaf area. Pinus tabuliformis stagnated the highest volume of (3.89±0.026) μg ·cm-2, followed by Pinus bungeana of (2.82±0.392) μg ·cm-2, and Populus tomentosa stagnated the minimum of (2.00±0.118) μg ·cm-2; ②Through observing the leaf microstructure morphology, coniferous species were found to have tightly packed stomas, stoma density and surface roughness higher than those of broad-leaved species, and they could also secrete oil; ③In different polluted regions, the leaves of the same tree species showed significant difference in stagnating TSP. Per unit leaf area, the tree species leaves situated around the 5th Ring Road had higher ability to absorb TSP than the tree species leaves at Botanical Garden, while their abilities to absorb PM2.5 showed no significant difference; ④In different polluted regions, significantly adaptive changes were found in leaf structure. Comparing to the region with light pollution, the outer epidermal cells of the plant leaves in region with heavy pollution shrank, and the roughness of the leaf skin textures as well as the stomatal frequency and villous length increased. In spite of the significant changes in plant leaves exposed to the heavy pollution, these plants could still maintain normal and healthy growth. |
|
|
|
