中文摘要：

以降香黄檀（Dalbergia odorifera）、顶果木（Acrocarpus fraxinifolius）、格木（Erythrophleum fordii）、红锥（Castanopsis hystrix）和西南桦（Betula alnoides）等树种幼苗为研究对象，对其叶片的光合特征进行研究。结果表明，降香黄檀、西南桦与顶果木具有较高的光饱和点（LSP）及光补偿点（LCP），较为喜光；红锥及格木则具有较低的LCP及LSP，较为耐荫。降香黄檀和顶果木都具有较高的光饱和净光合速率（Amax），但降香黄檀的羧化效率（CE）最高，CO2补偿点（CCP）最低，气孔导度（gs）及胞间CO2浓度（Ci）却并不高，这表明其羧化酶较高的CO2羧化能力是造成其较高Amax的主要原因；而顶果木则是CE、gs及Ci都较高，CCP较低，羧化酶羧化能力与CO2提供能力都较强，因此光合能力较强。虽然西南桦有最高的gs及Ci，但较高的CCP及较低的CE限制了其光合能力；格木以及红锥则是gs、Ci与CE都较低，CCP较高，羧化能力与CO2提供能力都较弱，因而光合能力较弱。

英文摘要：

Leaf photosynthetic characteristics of five tree species, i.e. Dalbergia odorifera, Acrocarpus fraxinifolius, Erythrophleum fordii, Castanopsis hystrix and Betula alnoides seedlings were studied in this paper. The results showed that D. odorifera, B. alnoides and A. fraxinifolius had higher light saturation point （LSP） and light compensation point （LCP） than C. hystrix and E. fordii, so that the former group could make better use of highintensity illumination, while the later group could tolerate shading. High utilization capacity of CO2 （i.e. lower carbon dioxide compensation point （CCP） and higher carboxylation efficiency （CE）） enabled D. odorifera with high photosynthetic capacity. Balanced supply capacity of CO2 （i.e. stomatal conductance （gs） and intercellular CO2 concentration （Ci）） and utilization capacity of CO2 enabled A. fraxinifolius with high photosynthetic capacity too. Although B. alnoides had high capacity of supplying CO2to photosynthetic apparatus, low capacity of using CO2limited its photosynthetic capacity. E. fordii and C. hystrix had low supply and utilization capacity of CO2, resulting in their lower photosynthetic capacity than the other tree species.