论文部分内容阅读
通过搭建遮光棚模拟空旷地(不遮光对照)、林隙(46%遮光)、林下(81%遮光)等3种光照环境,研究了黑松Pinus thunbergii,油松Pinus tabuliformis,赤松Pinus densiflora等幼树叶片光合特性和叶绿素荧光动力学特征随梯度光照强度的变化规律,以期了解3个树种对不同光环境的适应性对策,为华北地区人工林的天然更新及长期经营提供理论依据。结果表明:随着光照强度的降低,黑松幼树净光合速率(P_n),蒸腾速率(T_r),水分利用效率(E_(WUE)),性能指数(I_(abs)),质体醌库的面积(S_m),PSⅡ捕获的能量从Q_A传递到Q_B的效率(Ψ_O),PSⅡ捕获的能量从Q_B传递到PSⅠ的效率(Ψ_(RE)),单位反应中心吸收(ABS/RC)、捕获(TRo/RC)、用于电子传递(ETo/RC)的能量均减小。油松幼树净光合速率(P_n),水分利用效率(E_(WUE)),性能指数(I_(abs)),PSⅡ捕获的能量从Q_A传递到Q_B的效率(Ψ_O),PSⅡ捕获的能量从Q_B传递到PSⅠ的效率(Ψ_(RE)),单位反应中心吸收(ABS/RC)、捕获(TRo/RC)、用于电子传递(ETo/RC)的能量在46%遮光条件下达到最大值。赤松幼树光合特征参数及叶绿素荧光参数在不同遮光条件下差异不显著(P>0.05)。因此,赤松对弱光的利用能力最强,能够适应不同的光照环境;黑松在光照充足的环境中生长状况较好;油松适宜在轻度遮光的林隙环境中生长。
Pinus thunbergii, Pinus tabuliformis, Pinus densiflora, etc. were studied by setting up a light shed to simulate three kinds of light conditions in the open area (no shading control), gap (46% shading) and under the shade (81% shading) The changes of photosynthetic characteristics and chlorophyll fluorescence kinetics of young trees with the light intensity of gradient were studied in order to understand the adaptive strategies of three tree species to different light environments and to provide theoretical basis for natural regeneration and long-term management of plantations in North China. The results showed that the net photosynthetic rate (P_n), transpiration rate (T_r), water use efficiency (E_ (WUE)), performance index (I abs) (Ψ_ (RE)), the area absorbed by the PSⅡ (Q_A), the efficiency of PSⅡ capture from Q_A to Q_B (Ψ_O), the efficiency of PSⅡ capture from Q_B to PSⅠ (Ψ_ (RE)), (TRo / RC), the energy used for electron transfer (ETo / RC) is reduced. The net photosynthetic rate (P_n), water use efficiency (E_ (WUE)), performance index (I abs), the efficiency of PS Ⅱ trapping energy transferred from Q_A to Q_B (Ψ_O) Q_B Energy delivered to PSI (Ψ_ (RE)), ABS / RC, TRo / RC, and energy used for electron transport (ETo / RC) peaked at 46% shading . Photosynthetic characteristics and chlorophyll fluorescence parameters of saplings were not significantly different under different light shading conditions (P> 0.05). Therefore, Adenophora has the strongest utilization ability to low light, and can adapt to different light environments. The growth of Pinus thunbergii in a well-lit environment is good, and the Pinus tabulaeformis is suitable for growing in light-sheltered gaps.