百山祖两种阔叶木本植物的光合蒸腾作用特性研究  

Study on Photosynthesis-transpiration Characteristics of Two Broadleaf Woody Plant Species in the Forests of Baishanzu

作　　者：吴雁雯 张金池[1] 顾哲衍[1] 刘鑫[1] 韩诚[1] 

机构地区：[1]南京林业大学,南京210037

出　　处：《水土保持研究》2014年第6期204-210,共7页Research of Soil and Water Conservation

基　　金：国家公益林行业重大专项"典型森林植被对水资源形成过程的调控研究"(201104005)

摘　　要：利用Li-6400便携式光合测定仪分别对凤阳山—百山祖国家级自然保护区阔叶混交林中2种常见木本植物尖萼紫茎(Stewartia acutisepala)和小叶白辛树(Pterostyrax corymbosus)的光合蒸腾特性进行了研究,并应用相关性分析与逐步回归分析法就上述植物各生理生态因子对净光合速率(Pn)和蒸腾速率(Tr)的影响进行了分析。结果表明:(1)尖萼紫茎的Pn主要影响因子是水分利用率(WUE)、太阳辐射(PYR),而小叶白辛树的主要影响因子则是胞间CO2摩尔分数(Ci),PYR,且在Pn日变化过程中,尖萼紫茎的值始终大于小叶白辛树,可以判断尖萼紫茎的光合作用比小叶白辛树要强;(2)影响尖萼紫茎Tr的主要因子是气孔导度(Gs)及光合有效辐射(PAR),影响小叶白辛树的主要因子则是Gs、空气相对湿度(RH),而据Tr日变化可发现尖萼紫茎的蒸腾作用强于小叶白辛树;(3)对2种植物WUE的分析可知,尖萼紫茎的碳水平衡性优于小叶白辛树。且总体而言,在该生境中,制约尖萼紫茎光合蒸腾作用的因子比小叶白辛树少。因此,尖萼紫茎对该生境适应性优于小叶白辛树,分布更为广泛。Photosynthesis and transpiration play the significant roles in the evaluation of ecological benefits from a forest ecosystem. In order to determine their photosynthesis and transpiration characteristics at cano- py level, this paper conducted some measurements with Li-6400 portable photosynthetic apparatus on two typical tree species in the forest ecosystem of Fengyang Mountain. Results show that the main factors influ- encing Pn of Stewartia acutisepala were WUE and PYR, meanwhile, the main factors influencing Pn of Pterostyrax coryrnbosus were Ci and PYR. In the process of daily variation of P,, the value of Stewartia acu- tisepala was always higher than Pterostyrax coryrnbosus. It can be judged that the photosynthesis of Stew artia acutisepala was stronger than Pterostyrax corymbosus. Additionally, the main factors influencing Tr of Stewartia acutisepala were Gs and PAR, while the main factors influencing Tr of Pterostyrax coryrnbosus were Gs and RH. According to daily variation of Tr, the transpiration of Stewartia acutisepala was stronger than Pterostyrax coryrnbosus. According to the analysis of WUE, the carbon water balance ability of Stew- artia acutisepala was better than Pterostyrax coryrnbosus. Therefore, the adaptability of Stewartia acutise pala to this habitat was superior to Pterostyrax coryrnbosus, and the former was more widely distributed.

关 键 词：百山祖 净光合速率 蒸腾速率 生理因子 生态因子 

分 类 号：S718.43[农业科学—林学]