摘要
采用LI-6400xt便携式光合测定系统,对白云质砂石山地区适生树种翅荚香槐的春季光合作用日变化、光响应进行了分析,并分析光合生理与生态因子之间的关系。结果表明:(1)翅荚香槐净光合速率日变化为双峰曲线,分别在10:00和14:00达到峰值,有明显光合"午休"现象;胞间CO2浓度(Ci)的日变化与净光合速率(Pn)相反;蒸腾速率(Tr)、气孔导度(Gs)日变化均呈双峰曲线,与Pn相同;气孔限制值(Ls)的日变化与胞间CO2浓度的日变化曲线变化趋势相反;水分利用效率(WUE)日变化呈单峰曲线,日均值2.91μmol/mmol。(2)翅荚香槐的光饱和点(LSP)为984μmol/m^2·s、最大净光合速率(Pnmax)为18.46μmol/m^2·s、暗呼吸速率(Rd)为-1.39μmol/m^2·s、表观量子效率(α)为0.0445,光补偿点(LCP)为18.37μmol/m^2·s。(3)净光合速率与环境因子简单相关性分析表明,各环境因子对翅荚香槐叶片净光合速率的影响大小为:Gs>PAR>Tr>Ci>RH>Ca>Ta。
Diumal changes of photosynthesis and light response curve of Cladrastis platycarpa(Maxim.) Makino were measured with LI-6400 xt portable photosynthesis system,and the relationship between photosynthetic physiology and ecological factors were analyzed. The results showed as follows :(1)The diurnal change of net photosynthesis rate(Pn) of C. platycarpa(Maxim.) Makino had a double-peak curve,exhibiting a clear midday depress,and the peak value reached at 10 :00 and 14 :00. Intercellular CO_2 concentration(Ci)had opposite diurnal variation compared with Pn. Diurnal variation of transpiration rate(Tr) and stomatal conductance(Cond) had a double-peak curve as Pn. Stomatal limits(Ls)had opposite diurnal variation compared with Ci. The diurnal variation of water use efficiency(WUE)showed inverse single-peak curve,daily average was 2.91μmol/mmol.(2)Light saturation point(LSP) of C. platycarpa(Maxim.) Makino was 984μmol/m^2·s,the maximum of net photosynthesis rate(Pnmax)was 18.46μmol/m^2·s,dark respiration rate(Rd)was-1.39μmol/m^2·s,initial quantum efficiency(α)was 0.0445,light compensation point(LCP) was 18.37μmol/m^2·s.(3)The net photosynthetic rate and environmental factors correlation analysis showed that :Pn was influenced by environmental factors in the order from high to low :Gs>PAR>Tr>Ci>RH>Ca>Ta.
出处
《广东农业科学》
CAS
2017年第9期41-47,共7页
Guangdong Agricultural Sciences
基金
国家重点研发计划项目(2016YFC0502605)
贵州省科技厅项目(黔科合S字[2007]1024)
贵州省林业科学研究院士工作站项目(黔科合院士站[2014]4006)
关键词
白云质砂石山
翅荚香槐
光合特性
dolomite rocky hills
Cladrastis platycarpa(Maxim.) Makino
photosynthetic characteristics
