岩生红豆苗木光合特性初步研究

A Preliminary Study on the Photosynthetic Characteristics of Ormoia saxatilia

为探讨岩生红豆苗木的光合特性,采用Li-6400XT便携式光合仪测定了岩生红豆苗木叶片光合作用的各指标参数。结果表明:1净光合速率日变化呈单峰曲线,光合最佳时段(峰值)在上午,同时日均值高,属阳性树种,光合能力和CO2固定能力较强;2蒸腾速率呈双峰曲线,存在"午休"现象,水分利用效率日变化呈"W"型曲线,二者日均值不高,土壤水分利用率低;3光饱和点高而光补偿点低,对光环境具有较强的适应能力,属偏喜光树种;4CO2饱和点略低而CO2补偿点较高,生长对大气CO2浓度要求较高。栽培时,应给予充足的水分、足够的CO2和光环境,同时保证土壤通透性、排水性良好。

Li-6400XT portable photosynthetic system has been applied to measure the photosynthetic physiological parameters of Ormoia saxatilia, with the study of the photosynthetic ecophysiological characteristics of O. saxatilia. The result shows that, （1） Diurnal variation of net photosynthetic rate shows a single peak curve, morning is the best time of photosynthesis （peak）, while the average value is high, belong to sun species, having a strong capability in photosynthetic capacity and fixed CO2 ; （2） Transpiration rate curve is asymmetric bimodal, existing a midday depression, water use efficiency curve was ＂W＂, the two daily average value is not high, and having a low utilization rate of soil water; （3） Having a higher CO2 compensation point and CO2 saturation point, a strong ability to adapt to light environment, it is the light tree species; （4） The high light saturation point and low light compensation point, growth on atmospheric CO2 concentration is higher, it should be given to plenty of water, adequate CO2 and fight environment, while ensuring a good soil permeability, drainage in cultivating.