中文摘要：

采用Li-6400测定了在短期CO2浓度倍增下毛竹光合作用对光照强度的季节响应，并对比同一测定毛竹在相同时期大气CO2浓度下的光响应曲线特征，结果表明：CO2浓度的增加促使毛竹最大净光合速率和光饱和点升高，光补偿点下降，而对光合量子效率的影响因季节而异，在夏、秋两季光合量子效率升高，冬季持平，春季降低，但全年来看还是具有促进作用；在相同的光照强度下，CO2浓度的倍增会使毛竹的净光合速率和水分利用率升高，而蒸腾速率和暗呼吸速率下降。CO2浓度倍增后，各光合生理特征参数的季节变化基本和大气CO2浓度下的季节变化相同，均与毛竹叶片的生理活性密切相关；而在不同季节，毛竹对CO2浓度升高的响应差异性是造成季节变化规律稍有不同的主要原因之一，证实了植物对短期CO2浓度升高的光合生理响应行为。

英文摘要：

By using Li -6400, the seasonal photosynthetic responses of PhyUostachys edulis to light under the short - term doubled CO2 concentration were determined, and the features of the response were compared with those of the corresponding photosynthetic responses to light under atmospheric CO2 concentration. The main study results are as follows：At high CO2 concentration level, the maximal net photosynthetic rate （Pmax） and light saturate point （LSP） will be raised while the light compensate point （LCP） will be lowered. Although the apparent quantum yield （AQY） was enhanced at the annual average value of 6.25%, its response to the elevated CO2 concentration changed with seasons： it increased in summer and autumn, decreased in spring, and had no change in winter. Under the same light intensity （1 000 umol/m^2 · s）, the elevated CO2 concentration increased net photosynthetic rate （Pn） and water use efficiency （WUE）, and decreased transpiration rate （Tr） and dark respiration rate （Rd）. After CO2 concentration was doubled, the seasonal variation tendency of photosynthetic characters were similar to those under atmospheric CO2 concentration, it was closely related with seasonal changes of the leave＇ s physiological activity. The different responses of Phyllostachys edulis to the elevated CO2 concentration in four seasons were the main reason, which led to slight changes in seasonal variation tendency. Moreover, the photosynthetic response behavior of plants to the shortterm elevated CO2 concentration is proved in this study.