中文摘要：

以沈阳市主要绿化灌木水蜡（Ligustrum obtusifolium Sieb.）为实验材料，利用开顶箱（OTC）模拟法，研究了高浓度O3急性熏蒸对水蜡成年叶片表皮气孔及叶组织结构特征影响的变化规律。结果表明：在160 nmol·mol-1的高浓度O3处理（136 d）条件下，与对照相比，水蜡叶片近轴端气孔长度、宽度、周长、面积分别降低12.9%、8.4%、8.2%和15.0%,叶片远轴端分别降低16.7%、9.8%、13.3%和23.6%；气孔开度分别降低69.2%和393%;大气O3浓度升高对气孔密度没有显著影响（P 〉0.05）;叶片近轴端与远轴端栅栏组织厚度分别升高10.2%和7.3%，栅栏组织与海绵组织的比值分别升高28.9%和29.5%；海绵组织厚度分别降低15.1%和16.8%；上表皮厚度分别升高18.9%和11.5%，下表皮厚度分别升高23.1%和16.0%；叶片总厚度变化未达到显著水平（P 〉0.05）。这一结果为深入研究全球气候变化背景下城市植物的叶组织结构和功能在适应大气O3浓度变化方面提供了新的资料和证据。

英文摘要：

An experiment was conducted to study the characters of epidermis stomata and leaf tissue structure of Ligustrum obtusifolium seedlings exposed to elevated O3 concentration （160 nmol·mol-1） for 136 days in open top chamber （OTC）. The results showed that elevated O3 decreased the stomatal length, width, perimeter and area in adaxial leaves of L. obtusifolium by 12.9%, 8.4%, 8.2%, and 15.0%, respectively, while decreased by 16.8%, 9.8%, 13.3%, and 23.6%, respectively in abaxial leaves. The stomatal aperture decreased by 69.2% in adaxial leaves （P 〈0.05）, and decreased by 39.3% in abaxial leaves （P 〈0.05）. The elevated O3 concentration did not have significant effect on stomatal density （P 〉0.05）. Under elevated O3, the thickness of palisade tissue and thickness ratio of palisade tissue to spongy tissue in adaxial leaves increased by 10.2% and 28.9%, respectively, and increased by 7.3% and 295% in abaxial leaves, respectively （P 〈0.01）. The thickness of spongy tissue decreased by 15.1% in adaxial leaves, and decreased by 16.8% in abaxial leaves （P〈0.01）. The thickness of upper and lower epidermis increased by 18.9% and 23.1% in adaxial leaves, respectively, and increased by 11.5% and 16.0% in abaxial leaves （P〈0.05）. The leaf thickness increased slightly （P〉0.05）. These results provided new evidence for the research in the effects of elevated O3 on leaf tissue structure and function of urban plants under the background of global climate change.