A systematic test was carried out on photosynthesis and chlorophyll fluorescence characteristics of Nerium indicum Mill. , which were grown in different sites far from the coastline, using Li-6400 (Li-COR,Co. USA) and PAM-2500 (Walz, German). Results show that wind loading has a significant impact on the photosynthesis and transpiration characteristics of N. indicum. The net photosynthesis rate and transpiration rate of trees grown in site D4, which are nearest to the coastline and also share the biggest wind loading, were obviously lower than those of other sites (i. e. sites D5, D6, D7 , D8) . Meanwhile, the net photosynthesis rate, transpiration rate, initial fluorescence ( Fo ) , and photochemical efficiency (F_v/Fm) of leaves increased with increasing distance of the trees from the coastline. Photochemical quenching ( FP ) and non-photochemical quenching ( FN ) were different between different sites, but there was no significant difference ( P>0.05 ) . The east-facing leaves, which also faced the main wind direction, did not show significant difference in photosynthesis and fluorescence characteristics compared with those facing other three directions (i. e south, west, north) .%采用 LI-6400便携式光合作用测定仪和PAM-2500便携式调制叶绿素荧光测定仪对距海岸线不同距离夹竹桃叶片的光合作用和叶绿素荧光特性进行了系统测量.结果表明:风力胁迫对夹竹桃叶片的光合、蒸腾特征产生明显的影响,离海岸线最近(风速最大)的D4(距海岸线4km)处的夹竹桃叶片净光合速率(Pn)、蒸腾速率(Tr)明显低于其他各点(距离海岸线5、6、7、8 km,分别标记为D5、D6、D7、D8),并且随着海岸线距离的增加,Pn和Tr都呈上升的趋势；随着海岸线距离的增加,Fo、Fv/Fm逐渐增大,qP与qN发生一定的变化,但差异不显著(P＞0.05)；夹竹桃东方向叶片作为主要的迎风面,并没有因为长期的风胁迫而与其他3个方向的叶片光合、荧光特征产生明显的不同.
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