凤阳山阔叶混交林主要树种光合蒸腾特性研究--基于灰色关联法

Analysis of photosynthesis and transpiration characteristics of typical tree species in the broad-leaved mixed forest of Fengyang Mountain——based on grey correlation method

利用Li-6400便携式光合测定仪分别对雷公鹅耳枥(Viminea wall)、云锦杜鹃(Rhododendron fortunei)、木荷(Schima superba)、褐叶青冈(Cyclobalanopsis stewardiana)、温州冬青(Ilex wenchowensis)、水丝梨(Sycopsis)等树种的光合蒸腾特性进行了研究,并利用灰色关联法分析了上述植物各生理生态因子对净光合速率(Pn)和蒸腾速率(Tr)的影响。结果表明:在Pn日变化中,仅温州冬青呈现双峰值,雷公鹅耳枥、云锦杜鹃和温州冬青利用弱光的能力较强,尤以云锦杜鹃最强;Tr日变化主要受气孔导度(Gs)和叶片水压亏缺(Dvp)两个因子影响,云锦杜鹃与木荷Tr日均值较小且Pn日均值较大,能更为有效地积累碳同化量;影响植物Pn的主要因子有Gs、水分利用效率(EWU)和光合有效辐射(RPA),而影响植物Tr的主要因子包括Gs与RPA;云锦杜鹃对生境的适应性与抗逆性相对较强,而水丝梨适应该地区环境的能力相对较弱。

This paper conducted some measurements,with Li-6400 portable photosynthetic apparatus ,on six typical tree species, namely, Viminea wall, Rhododendron fortunei, Schima superba, Cyclobalanopsis stewardiana, llex wenchowensis, Sycopsis and so on within the forest ecosystem of Fengyang Mountain. Their photosynthesis and transpiration characteristics in diurnal patterns at canopy level were determind. Furthermore, the influence degree of physiological and ecological factors on net photosynthetic rate （ Pn ） and transpiration rate （ Tr ） were analysed and compared by using grey correlation method.Results showed that only llex werwhowensis presented double peak in the daily variation of Pn, Rh. fortunei had the strongest ability to use weak light. The main factors influencing Tr were stomatal conductance （ Gs ） and leaf vapor pressure deficit （ Dvp ）. The daily average transpiration rate of Rh. fortunei and S. superba were lower while the daily average net photosynthetic rates of those two tree species were higher, so that their ability to accumulate carbon assimilation was more stronger;The main factors affecting the plant P were stomatal conductance （ Q ） and water use efficiency （Ewv） , meanwhile, the main factors affecting the plant Tr were Gs and photosynthetic active radiation（ Rpa ）. According to the grey correlation analysis, Rh. fortunei possesses superior adaption and resistence to the habitat, S. sinensis has weak ability to adapt to the habitat due to the restriction by illumination, stomates and moisture.