摘要
应用CI-301PS便携式光合测定仪对独叶草(Kingdoniauniflora)营养叶的光合生理生态特征进行了研究。结果表明:独叶草的净光合速率(Pn)日变化曲线呈双峰型,峰值出现在13:30和16:30左右,具有明显的光合"午休"现象;其叶片的蒸腾速率(Tr),水分利用率(WUE)的变化也呈双峰型。自然条件下,独叶草叶片净光合速率与光合有效辐射(PAR)、蒸腾速率、气孔导度(Gs)之间都具有多项式回归关系,R2分别为0·2082、0·2016和0·0582(n=129,P<0·05),但独叶草叶片净光合速率与空气温度(Ta)相关性不显著(P>0·05)。独叶草叶片的光补偿点(LCP)、光饱和点(LSP)分别为14·93和215·76μmol·m-2·s-1,只能适应较窄的光照环境。
By using CI-301PS portable photosynthesis system, this paper studied the photosynthetic characteristics of Kingdonia uniflora under natural condition. The results showed that the diurnal change of net photosynthetic rate （ Pn ） presented a bimodal pattern, i. e. , reached the maximum at 13：30 and 16：30, and had a midday depression. The diurnal variation patterns of leaf transpiration rate （T） and water use efficiency （WUE） were also bimodal. There were significant polynomial regressive relationships between Pn and photosynthetic active radiation （PAR）, Tr and stomatal conductance （Gs） （R^2 =0.2082, 0.2016 and 0. 0582, respectively, n = 129, P 〈 0. 05 ）, while no significant correlation was observed between Pn and air temperature （Ta） （P 〉0.05）. The light compensation point （LCP） was 14.93 μmol · m^-2 · s^-1, and the light saturation point （LSP） was 215.76 μmol · m^-2 · s^-1, suggesting that K. uniflora could only adapt to restricted light condition.
出处
《生态学杂志》
CAS
CSCD
北大核心
2007年第7期1038-1042,共5页
Chinese Journal of Ecology
基金
陕西省自然科学基金资助项目(2005SM17)
关键词
独叶草
净光合速率
蒸腾速率
光饱和点
光补偿点
Kingdonia uniflora
net photosynthetic rate
transpiration rate
light saturation point
light compensation point.
