中文摘要：

黄栌（Cotinus coggygria Scop.）和小叶白蜡（Fraxinus bungeana DC.）是两种常见的园林树种,本文以黄栌和小叶白蜡为研究对象,研究了2树种的光合特性。结果表明：有光合＂午休＂现象净光合速率日变化曲线均呈现双峰型,有光合＂午休＂现象;在强光条件下,黄栌的净光合速率（Pn）、瞬时水分利用效率（WUE）、表观光能利用效率（LUE）和表观CO2利用效率（CUE）均高于小叶白蜡,证明黄栌对强光的适应性要高于小叶白蜡。

英文摘要：

Cotinus coggygria Scop.and Fraxinus bungeana DC.are two common greening tree species.The Photosynthetic Characteristics of C.coggygria and F.bungeana were studied in field condition.The results showed that the photosynthetic rates of two species experienced significant depression at midday,and the diurnal photosynthetic rate of them all appeared a two-peak pattern.In high irradiance,the photosynthetic rate,water use efficiency,light use efficiency and CO2 use efficiency are high than F.bungeana,which show that the adaptation of C.coggygria to high energy is higher than F.bungeana.