18种城市园林树种光合耐脱水能力及抗旱性综合评价OA北大核心CSTPCD

With the rise of temperature and deficit of vapor pressure caused by global climate change in the future,it is of great significancejavascript:void(0);to select drought-tolerant urban tree species for urban greening.Eighteen urban tree species were used to investigate the difference of leaf photosynthetic desicca-tion tolerance(leaf relative water content corresponding to the initial decrease of potential quantum effi-ciency of PS Ⅱ during the dehydration process,RWCcrit)and their relationship with leaf morphology(leaf area,mass per area,dry matter content,thickness and density)and anatomical traits(stomatal density,length and index;thickness and area proportion of adaxial epidermis,abaxial epidermis,palisade tissue,spongy tissue and vascular bundles in the cross-section).The results exhibited that the RWCcrit of 18 urban tree species ranged from 30.2％to 58.0％with an average of 44.7％.The RWCcrit was significantly and positively correlated with leaf area,and significantly and negatively correlated with the proportion of lower epidermis area in leaf cross-section,and the RWCcrit values of 18 urban tree species were consistent with their comprehensive drought resistance.Therefore,RWCcrit can be applied to predict the drought-tolerant of urban tree species to a certain extent.The results are valuable for the selection of drought-tolerant urban tree species and rational management in the future.