在长白山森林生态系统定位站以开顶箱方式研究了CO2 含量升高后 ,水曲柳幼苗对CO2 和水分的利用情况。结果表明 :高含量CO2 下叶片的净光合速率明显比大气CO2 下生长的两对照组幼苗高 ,7× 10 -4 ,5× 10 -4CO2 下叶片的净光合速率基本相同 ;高含量CO2 提高了水曲柳叶片的水分利用效率 ,7× 10 -4 CO2 对增大叶片气孔阻力及水分利用效率要比 5× 10 -4 CO2 明显 ;5× 10 -4 CO2 下的水分利用效率增加主要是净光合速率较高所致 ,而 7×10 -4 CO2 下的水分利用效率提高是净光合速率增加与气孔阻力增大后所带来的蒸腾速率降低共同作用的结果
【英文摘要】
The utilization of CO 2 and H 2O of Fraxinus mandshurica seedlings which were grown in open-top chambers were determined at the Open Research Station of Changbai Mountain Forest Ecosystems. The results showed that the net photosynthetic rate under elevated CO 2 is significantly higher than that under ambient CO 2. The net photosynthetic rate under 7×10 -4 CO 2 is the same as that under 5×10 -4 CO 2. Water use efficiencies of leaves of Fraxinus mandshurica seedling increase under elevat...