14种华南乡土树种对交通尾气污染的光合生理反应

摘要

In order to reveal the photosynthetic responses to auto-exhaust pollution,the photosynthetic parameters of 1 4 native species of south China,planted in botanical garden and road greenland respectively,were tested and contras-ted.The results showed that there were three kinds of photosynthetic responses to auto-exhaust pollution of the n-ative species,such as up-regulation of photosynthesis,down-regulation of photosynthesis and non-regulation of photo-synthesis.The photosynthesis of Helicia cochinchinensis was up-regulated by raising its stomatal conductance,chlo-rophyll content and optimal PSⅡefficiency.Seven species of non-regulation of photosynthesis,included Desmos chinensis,Syzygium hancei,Liquidambar formosana,Machilus chinensis,Photinia serrulata,Cinnamomum cam-phora and Psychotria asiatica,had the ability to harmonize the up-regulation and down-regulation among stomatal conductance,chlorophyll content and optimal PSⅡefficiency.As for species of down-regulation of photosynthesis,in-cluded Elaeocarpus sylvestris,Erythrophleumfordii,Cryptocarya concinna,Cyclobalanopsis hui,Gardenia jasmi-noides and Michelia maudiae,they were sensitive to auto-exhaust pollution,and had no ability to prevent the decline of photosynthesis.%为揭示植物对交通尾气污染的光合反应，对14种华南乡土树种在植物园和道路绿地中的光合生理指标进行比较。结果表明：交通尾气污染胁迫下，越南山龙眼能通过提升气孔导度(Gs)、叶绿素含量(Ct)和光能转化效率(Fv/Fm)将其光合能力向上调节；假鹰爪、红鳞蒲桃、枫香、华润楠、红叶石楠、樟树和九节等7个树种能通过协调Gs、Ct和Fv/Fm三者间的此消彼长，保证其光合能力不明显变化；山杜英、格木、黄果厚壳桂、胡氏青冈、黄栀子和深山含笑等6个树种对交通尾气污染较敏感，抗污染能力不强，光合能力向下调节。