作　　者： ; ;

机构地区： 中山大学生命科学学院

出　　处： 《生态学报》 1999年第2期164-169,共6页

摘　　要： 用ＣＩＤ－３０１ＰＳ便携式光合作用测定仪的开放系统研究了生长于庐山山地上秋苗叶片的光合特性春对蔗荫的不与适应性，结果表明：（１）在夏季晴天、土壤供水充足的条件下，鹅掌楸苗期向阳叶片的光合速率有明显的午休现象，这可能与气孔限制和光抑制有关。（２）鹅掌楸苗期的光饱和点为１２００μｍｏｌｐｈｏｔｏｎｓ／ｍ＾２ｓ左右，光补偿点为２０μｍｏｌ ｐｈｏｔｏｎｓ／ｍ＾２·ｓ左右。 With the aid of the CI301PS portable photosynthesis system,a field study on the photosynthetic characteristics in leaves of Liriodendron chinense seedlings was made.The midday photosynthetic depression was observed on sunny day in summer,which was possibly due to the stomatal limitation and photoinhibition of photosynthesis.The light compensation point was about 20μ mol photons/m2s,the light saturation point was around 1200μmol photons/m2s,and the lightsaturating photosynthetic rate was in a range of 8～10μmol CO2/m2s.The CO2 compensation concentration of photosynthesis was more than 60μmol/mol.These indicated that although L.chinense was of a C3 type,sun plant its seedling could tolerate shade to a certain level.The responses of transpiration,stomatal resistance and internal CO2 concentration(Ci) of L.chinense to shade were different at different time in a day.By the stepwise multiple regression,it was found that PAR,R and Ci were the most dominant factors affecting the photsynthesis rate of L.chinense.Moreover,the solar energy utilization efficiency of L.chinense was about 094%.

关 键 词： 鹅掌楸 光合速率 光能利用率 蒸腾速率 气孔阻力

领　　域： [生物学] [农业科学] [农业科学]