大别山山核桃幼树生长环境及其光合特性研究

The Research on Growth Environment and Photosynthetic Characteristics of Carya cathyensis Sarg Sapling

使用LI-6400便携式光合作用测定系统,对大别山山核桃幼树的光合特性进行了研究。结果表明：在夏季,大别山山核桃幼树叶片净光合速率的日变化呈双峰型,有明显的＂光合午休＂现象,其光饱和点约为339μmol/（m2·s）,光补偿点约为33.2μmol/（m2·s）;在控制光照强度和温度的条件下,升高CO2浓度可提高大别山山核桃的净光合速率,提高幼树叶片对光能的利用率,CO2饱和点约为1200μL/L,补偿点约为60~70μL/L;对高温（〉25℃）的反应敏感,属中性植物。调查地区的环境条件基本能够满足大别山山核桃的生长需求。

The LI-6400 Portable photosynthesis was used to study the photosynthetic characteristics in leaveso f Carya cathyensis Sarg sapling.The results showed that the daily variation of net photosynthetic rate in leavesp resented a bimodal curve,and there was an obvious＇midday depression＇phenomenon,the light saturationp oint was about 339μmol/（m 2 ·s）,the light compensation point was about 33.2μmol/（m 2 ·s）.Under the condition of optimum light intensity and temperature,elevation of CO 2 concentration increased the Pn and the efficiency of high utilizing in Carya cathyensis Sarg sapling.The CO 2 saturation point was about 1200μL/L andC O 2 compensation point was about 60~70μL/L.The photosynthesis was more sensitive to the highert emperature（25℃）,belonging to neutral plant.The environmental conditions of the research are as could meet the basic needs of Carya cathyensis Sarg sapling＇s growth.