交通尾气污染对4种乡土行道植物叶片气孔形态和叶绿素含量的影响

Effects of Auto-exhaust Pollution on Leaf Stomatal Morphology and Chlorophyll Content of Four Native Avenue Trees

分别选取东莞市交通繁忙路段(污染区)和东莞植物园(对照区)的4种乡土行道植物,观测不同年龄叶片的气孔形态和叶绿素含量,了解交通污染对乡土植物形态和生理的影响及植物的响应。结果表明,污染区和对照区同种植物气孔形态没有明显差异,随着叶片年龄增加气孔形态发生一定变化,不同物种气孔被表皮附属物覆盖程度不同;污染区植物都不同程度地增加气孔密度,减小气孔大小;交通污染对叶绿素a和叶绿素a/b含量的影响不显著。

With the aim of understanding the impacts of auto-exhaust pollution on the morphology and physiology of native avenue trees,the morphological parameters of stomata（leaf stomatal density and length） and chlorophyll content of leaves at different developmental stages among four native avenue trees grown at Dongguan Botanical Garden（control plot） and Dongguan Road（polluted plot） with a very high traffic density were studied comparatively.The results showed that little difference in stomatal morphology was found between species grown at Dongguan Botanical Garden and Dongguan Road,but leaf epidermal appendages were different among four species.Compared to Dongguan Botanical Garden,stomatal density of the four studied species was increased,but stomatal length was significantly decreased.The effects of auto-exhaust pollution on the content of chlorophyll a and the value of chlorophyll a/b weren＇t significant.