30种2～3年生园林植物分别盆栽于不同污染强度的工业生产区、交通繁忙区和相对清洁区，在第一生长季结束后对各试验区植物叶片气体交换特征参数进行测定，评价了大气污染对不同植物种类的可能影响效果。结果表明：工业污染区和交通繁忙区均有较高的SO2浓度，交通繁忙区NOx浓度明显高于其它试验区。根据综合污染指数，3个试验区污染强度为交通繁忙区>工业污染区>相对清洁区。生长在污染区的大多数植物的净光合速率（Pn）、蒸腾速率(E)和气孔导度（gs） 均出现不同程度的下降，下降幅度因植物种类不同而有较大差异。植物Pn、E与gs之间存在显著线性相关关系，表明多数植物能够感应污染胁迫和调节气孔开张度，是植物对胁迫环境的一种适应策略。但是污染胁迫下Pn、E与gs线性相关的显著程度被削弱，表现出污染胁迫下不同植物种类Pn和E的变化与gs变化的不协同性和复杂性。根据Pn下降程度可将植物分组为轻度敏感（11种）、中度敏感（11种）和高度敏感植物（8种）。
Air pollution is a major environmental problem in cities. Much progress have been achieved in air monitoring and quality assessment at regional and national level based on emission inventories and measurements of ambient air concentrations taken by physical and chemical methods. The results of ambient air measurements make it possible to decide whether or not to limit the emission of certain pollutants. However, they do not permit direct conclusions on the effects of the measured pollutant concentrations on living organisms. The purpose of this study is to test the sensitivity of 30 2-3 year-old garden species transplanted into pots and exposed to differently polluted sites for 4 months during the growing season. Measurements on gas exchange parameters were made by using LCA-4 photosynthesis system. Based on these measurements, assessments of possible effects of air pollution on plants and their tolerance were also made. Monitoring data showed that the heavy traffic area received a much higher concentration of NOx than the industrial site, and both sites had high concentrations of SO2. The sites can be categorized from heavy to less pollution level in the order of heavy traffic area, industrial area, and relatively clean area by using an integrated pollution index. The Pn, E,gs differed among species and decreased for most species under polluted area. The Pn and E were closely linearly correlated with the gs under the relative clean site and polluted site，suggesting that most species had the ability to adapt to the pollution stress by adjusting stomatal operation. The evidence that the correlation of the Pn and E with g s had been weakened under the pollution stress also showed the unparallel nature and complexity in changes of Pn, E and gs. Based on the change in Pn, plants might be ranked as follows by their sensibility to air pollution： species that exhibited high sensitivity included Michelia maudiae, Allemanda schottii, Crateva trifoliate, Magnolia delavayi, Bischoffia jacanica, Lysidice rhodostegia, Michelia macclurei and Hibiscus rosa-sinensis. Species showing moderate sensitivity were Tristania confera, Bombax ceiba, Schefflera arboricola, Elaeocarpus hainanensis, Manglietia hainanensis, Elaeocarpus apiculatus, Swietenia mahagoni, Sterculia lanceolata, Fagraea ceilanica, Manifera persiciformis and Ficus macrocarpa, and those showing low sensitivity included Pittosporum tobira, Ficus altissima, Ficus microcarpa, Kigelia africana, Ficus benjamina, Mimusops elengi, Ormosia pinnata, Ficus elastica, Acmena accuminatissima, Nerium indicum and Ilex rotunda.