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通过测定土培条件下净光合速率及其相关参数的日进程，发现胡杨净光合速率的最大值出现在中午辐射最强的时间；胡杨光饱和点高达２８００μｍｏｌｍ－２ｓ－１，说明具有Ｃ４植物的光合特性，但ＣＯ２补偿点和饱和点分别高达１５０μｍｏｌｍｏｌ－１和９００μｍｏｌｍｏｌ－１，说明胡杨仍属于Ｃ３植物．此外，扫描电镜观察胡杨叶片表面有蜡片结构，可能与胡杨长期适应沙漠强辐射和高蒸腾的环境有关．胡杨气孔阻力全天变化不大，表明胡杨的气孔运动保留了河岸起源的特点，而典型的叶片旱生结构可能是长期适应干旱环境逐渐发育的结果
The maximum net photosynthetic rate of Populus euphratica appeared in the strongest noon time by measuring the diurnal course of net photosynthetic rate and its related parameters in soil culture. The photosynthetic rate of Populus euphratica reached 2800μmolm-2s-1, indicating that the maximum photosynthetic rate of Populus euphratica with C4 plants Photosynthetic characteristics, but CO2 compensation point and saturation point were as high as 150μmolmol-1 and 900μmolmol-1, indicating that Populus still belong to C3 plants. In addition, scanning electron microscopy observation of Populus euphratica leaf wax surface structure may be long-term adaptation of Populus euphratica desert radiation and high transpiration environment. The stomatal resistance of Populus euphratica changed little during the whole day, which indicated that the stomatal movement of Populus euphratica preserved the characteristics of riverbank origin. However, the typical structure of leaf xerophytes may be the result of long-term adaptation to the gradual development of drought environment