秦岭火地塘林区锐齿栎光合、蒸腾特性

Characteristics of Photosynthesis and Transpiration of Sharptooth Oak in Huoditang Forest Zone of the Qinling Mountains

以Li-6400便携式光合测定系统规定了秦岭火地塘林区主要成林树种锐齿栎的光合、蒸腾作用日进程、CO^2响应曲线、光响应曲线及其对CO^2倍增的响应。结果表明:正常大气 CO^2浓度下,锐齿栎叶片的光补偿点为25μmol·m^(-2)·s^(-1),光饱和点为1200μmol·m^(-2)·s^(-1),表观光量子效率为0.0511;CO^2倍增情况下,叶片的光补偿点下降为8μmol·m^(-2)·s^(-1),光饱和点上升为1800μmol·m^(-2)·s^(-1),表观光量子效率为0.069 6,饱和光强下叶片最大净光合速率增加121％。CO^2补偿点为53 μmol·mol^(-1),CO^2饱和点为1000 μmol·mol^(-1);叶片的羧化效率为0.0817;锐齿栎叶片净光合速率及蒸腾速率日进程在晴天均表现为双峰曲线,在阴天均表现为单峰曲线。

Sharptooth oak (Quercus aliena var. acuteserrata) is one of the most important afforestation tree species in Huoditang forest zone of the Qinling Mountains. Using Li - 6400 portable photosynthesis system, light curve, CO2 curve, diurnal courses of photosynthesis and transpiration of sharptooth oak were measured and analyzed in this paper. The main results are as follows; Under normal atmospheric CO2, the light compensation point, light saturation point and apparent quantum yield of sharptooth oak were about 25μmol . m^2 . s-1 ,1 200μmol . m^2 . s-1 and 0.051 1 respectively. Under doubled CO , the light compensation point, light saturation point and apparent quantum yield of sharptooth oak were about 8μmol . m ~2 . s-1, 1 800μmol . m ~2 . s-1 and 0.069 6 respectively. The maximum net photosynthetic rate at light saturation point increased 121%. The CO2 compensation point and saturation point were 53μmolmol-1 and 1 000μmolmol-1 respectively. The carboxylation efficiency was 0.081 7. The diurnal courses of photosynthesis and transpiration were double peaked in sunny day and single peaked in cloudy day respectively.