中文摘要：

以呼和浩特市的13种主要城市绿化植物为研究对象,采用LI-6400光合仪对植物的光合生理生态指标进行测定,对其固碳释氧效率进行量化研究,以探讨植物光合作用固定二氧化碳和释放氧气的效率,分析影响固碳释氧效率的因素,明确各植物的固碳释氧效率,为半干旱地区的城市绿化提供科学理论依据。结果显示：（1）不同植物的日光合速率的变化趋势不同,其中早熟禾、萱草、叉子圆柏、侧柏、云杉、圆柏、油松为单峰曲线,芍药、连翘、紫丁香、国槐、垂柳、新疆杨为双峰型;而在6月到11月中各植物的固碳量变化趋势表现基本相同,固碳量的高值出现在6月前后和9月前后。（2）植物固碳量排序为：连翘〉国槐〉新疆杨〉紫丁香〉油松〉叉子圆柏〉圆柏〉芍药〉萱草〉垂柳〉侧柏〉云杉〉早熟禾。（3）植物的固碳量与光合速率、蒸腾速率、空气温度、叶片温度之间均呈极显著相关关系。研究表明,在半干旱地区的城市绿化植物配置时,应优选固碳释氧相对较强的植物（落叶乔木为国槐、常绿乔木为油松,灌木为连翘,草本为芍药）,而固碳释氧能力较弱的植物可作为长寿植物种和观赏植物种选种。

英文摘要：

13 species of urban greening plants in Hohhot were selected for study.The photosynthetic physiology and ecology indexes of plants were measured by using LI-6400 portable photosynthesis system and the carbon fixation capacity of the plants were quantitatively studied.The effects of plant photosynthesis on the carbon fixation were studied.The factors affecting the efficiency of carbon sequestration were analyzed.The order of carbon sequestration efficiency was determined.The result indicated that： （1） different plants had different trends in daily carbon fixation, Poa pratensis, Hemerocallis fulva, Paeonia lactiflora an single peak curve, and Platycladus orientalis, Picea asperata, Sabina chinensis, Pinus tabuliformis, Sabina vulgaris, Forsythia suspensa, Syringa oblata, Sophora japonica, Salix babylonica, Populus alba var.pyramidalis had double-peak curve.From June to November, the trend of carbon sequestration of each plant was basically the same that the high value of carbon sequestration appeared around June, and before or after September.（2） Carbon sequestration of plants： Forsythia suspensa〉 Sophora japonica〉 Populus alba var.pyramidalis〉 Syringa oblata〉 Pinus tabuliformis〉 Sabina vulgaris〉 Sabina chinensis〉 Paeonia lactiflora〉 Hemerocallis fulva〉 Salix babylonica〉 Platycladus orientalis〉 Picea asperata〉 Poa pratensis;（3） there was a significant correlation between carbon sequestration and photosynthetic rate, transpiration rate and air temperature.According to the main species of carbon dioxide fixation and oxygen release analysis showed that the plant configuration, carbon fixation and oxygen release of relatively strong plants as the preferred plant （the arbors optimum with Sophora japonica, evergreen arbors with Pinus tabuliformis,the shrubs optimum with Forsythia suspensa, the herbaceous plants optimum with Paeonia lactiflora）, while carbon fixation ability could be used as a long-lived species and ornamental species, which were suitable for selection for a lar