根据森林循环理论,森林群落是处于不同发展阶段的镶嵌系统.测定了4个不同斑块类型(林窗斑块、建立斑块、成熟斑块和衰退斑块)下优势树种大别山五针松幼苗的光合生理特征.结果表明:随着森林循环,大别山五针松幼苗的净光合速率(Pn)、气孔导度(Gs)、蒸腾速率(Tr)、羧化效率(CE)、PSⅡ最大光化学效率(Fv/Fm)均呈现出先下降后上升的趋势.光化学猝灭系数(qP)、非光化学猝灭系数(qN)、PSⅡ量子产额(ΦPSⅡ)和电子传递速率(ETR)的日变化在林窗斑块中较大,而在成熟斑块较小.说明林窗斑块虽然环境因子的日变化较大,但较好的光照条件有利于大别山五针松幼苗的生长,而在成熟斑块阶段,虽然环境因子的日变化较温和,但较差的光照环境,抑制了大别山五针松幼苗的生长.%According to the forest cycle theory, forest communities are the embedded systems with different development patch types. The heterogeneity of the photosynthetic characteristics of Pinus dabeshanensis seedling in different patch types ( gap patch, building patch, mature patch and degenerate patch) were studied. Our results were as follows: compared to other patch phases, in gap patch phase, the seedlings of P. dabeshanensis exhibited the highest net photosynthetic rate ( Pn ) , stomatal conductance ( Gs ) , transpiration rate ( Tr ) , carboxylation efficiency ( CE) , and the maximum quantum efficiency of PSⅡ ( Fv/Fm ) . The diurnal variations of coeffi-cient of photochemical quenching ( qP) , coefficient of non-photochemical quenching ( qN) , PSⅡquantum yields (ΦPSⅡ) and elec-tron transport were ( ETR) the highest in the gap patch, and the lowest in the mature patch. Our results suggest that the gap patch is the optimal environment for their growth, and the mature patch inhabits the growth of P. dabeshanensis seedling.
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