中文摘要：

选取极端干旱区的策勒种群和干旱区的阜康种群,利用LI-6400测定了净光合速率（Pn）、蒸腾速率（Tr）、气孔导度（Gs）、光合有效辐射（PAR）、空气温度（Ta）、水汽压亏缺（Vpd）、相对湿度（RH）等相关参数,对2个不同分布区骆驼刺（Alhagi sparsifolia Shap.）的光合特性和水分代谢特性进行了比较研究。结果表明：不同地理种群骆驼刺适应环境的方式不同,策勒种群的光饱和点（1 300μmol·m^-2·s^-1）、光合最适宜温度（35℃）均高于阜康种群（光饱和点为1 000μmol·m^-2·s^-1,光合最适宜温度为31℃）;与阜康种群相比,策勒种群采用低光合、低蒸腾、高水分利用效率的节水对策来维持植物在极端干旱环境下的正常生长。策勒种群的净光合速率（5.68μmol·m^-2·s^-1）、蒸腾速率（2.71 mmol·m^-2·s^-1）和光能利用效率（10.35 mol·mol^-1）远低于阜康种群（净光合速率为8.57μmol·m^-2·s^-1,蒸腾速率为6.11 mmol·m^-2·s^-1,光能利用效率为12.56 mol·mol^-1）,而水分利用效率（1.79μmol·mmol^-1）和水汽压亏缺（3.96 k Pa）明显高于阜康种群（水分利用效率为1.33μmol·mmol^-1,水分亏缺为3.28 k Pa）,说明策勒种群对环境的适应能力更强。

英文摘要：

In order to investigate the ecological adaptation of Alhagi sparsifolia Shap. in different geographic populations,the relevant parameters,such as the net photosynthetic rate（ Pn）,transpiration rate（ Tr）,stomatal conductance（ Gs）,photosynthetically active radiation（ PAR）,air temperature（ Ta）,vapor pressure deficit（ Vpd）and relative humidity（ RH）,were measured. The characteristics of photosynthesis and water metabolism were experimentally studied and compared in the Qira population and Fukang population by using LI- 6400. The results revealed that the ways of adapting environment of plants growing in different geographic populations were different.The light saturation point（ 1 300 μmol·m^-2·s^-1） and optimum temperature（ 35 ℃） for photosynthesis in the Qira population were all lower than those in the Fukang population（ 1 000 μmol·m^-2·s^-1and 31 ℃）. Compared with the plants growing in the Fukang population,the plants growing in the Qira population needed the lower photosynthesis,lower transpiration and higher relative humidity to maintain their normal growth under the extremely arid environment. In the Qira population,the Pn（ 5. 68 μmol·m^-2·s^-1）,Tr（ 2. 71 mmol·m^-2·s^-1） and Tr（ 10. 35 mol·mol^-1） were much lower than those（ Pn： 8. 57 μmol·m^-2·s^-1,Tr： 6. 11 mmol·m^-2·s^-1and light use efficiency： 12. 56 mol · mol^-1） in the Qira population,but the water use efficiency（ 1. 79 μmol ·mmol^-1） and Vpd（ 3. 96 kPa） were obviously higher than those in the Fukang population. These revealed that the capability of adapting environment of the Qira population was higher than that of the Fukang population.