中文摘要：

研究了大叶女贞（Ligustrum lucidum Ait.）和小叶女贞（Ligustrum quihoui Carr.）在不同大气环境条件下叶片中Pb、Cd、叶绿素a（Chl a）、叶绿素b（Chl b）、类胡萝卜素（Car）的含量及比叶重（LMA）,分析了因素之间的相互关系.不同环境条件下叶片中Pb、Cd、Chl a、Chl b、Chl（a＋b）、Car的含量及LMA具有显著差异.随污染程度的加剧,叶片中Pb、Cd的含量、LMA和Chl a/Chl b升高,而Chl a、Chl b和Chl（a＋b）含量则呈现相反的变化趋势.大叶女贞叶片中Car含量变化不明显,而小叶女贞叶片中Car含量在污染严重的采样点明显较其他采样点高.2种植物叶片中Pb、Cd的含量对叶片LMA和光合色素含量均具有明显影响,Chl a、Chl b及Chl（a＋b）含量与叶片中Pb、Cd的含量呈显著负相关（P〈0.05）.叶片中Cd含量的增大导致Car含量增大,而Pb的作用与物种有关.叶片中Pb含量的增大导致2物种LMA增大,而Cd含量导致大叶女贞LMA增大而小叶女贞LMA变化不明显.污染胁迫下植物叶片会增大LMA、Chl a/Chl b,减小Chl a、Chl b和Chl（a＋b）含量,据此可对大气污染进行生物监测.

英文摘要：

The contents of Pb,Cd,photosynthetic pigments（chlorophyll a,chlorophyll b,chlorophyll（a＋b） and carotenoid） and leaf mass per area（LMA） of Ligustrum lucidum Ait.and Ligustrum quihoui Carr.under different urban atmospheric environment were measured.The correlations between the contents of Pb,Cd in leaves and photosynthetic pigments,LMA were analyzed as well.The two plants showed significant differences in their absorption of Pb and Cd,photosynthetic pigments,and LMA under different urban environmental conditions.There were four classes of sampling sites： serious pollution areas（SP）,medium level pollution areas（MLP）,light pollution areas（LP） and comparatively pollution-free area（CPF）.The general trend of contents of Pb,Cd,carotenoid in leaves and LMA was： SP MLP LP CPF.Chl a,Chl b,Chl（a＋b） also significantly differred among the sampling sites,however,they showed a reverse trend.The absorption of Pb and Cd reduced the contents of Chl a,Chl b and Chl（a＋b） in leaves,and significantly negative correlations（P0.05） were found between them.The contents of Cd in leaves increased the contents of carotenoid,but the effect of Pb was dependent on plant species.The absorption of Pb and Cd increased LMA of Ligustrum lucidum Ait..But for Ligustrum quihoui Carr.,the effects of Pb and Cd were different.LMA increased in parallel to the increasing contents of Pb in leaves.However,no obvious change in LMA of the effect of Cd was observed.Therefore,LMA,Chl a/Chl b and the contents of Chl a,Chl b,Chl（a＋b） in leaves appeared to be potentially good bio-indicators for urban air environmental quality.