摘要
植物功能群(PFG)把一系列植物归为一个功能团体,可以作为植被随环境动态变化的基本单元,简化相关研究。植物功能群内不同物种的生理特性差异是功能群存在的基础,也影响着功能群整体的功能。采用种间联结法并结合优势种在海拔梯度上的变化,将伏牛山自然保护区森林生态系统各层优势种划分为4组植物功能群,研究每组植物功能群内不同物种的光合特性。对光合-光响应、最大净光合速率(Pn)、暗呼吸速率(Rd)、光补偿点(LCP)、光饱合点(LSP)和表观量子效率(AQY)等指标进行分析和比较,结果表明:植物功能群内不同物种的光补偿点和暗呼吸速率的变异系数最高分别达70.47%和74.29%,功能性状存在着显著的互补性,这是物种能长期共存的主要原因。乔木的最大净光合速率在7—8μmol CO_2m^(-2)s^(-1)之间,对高光强的适应能力较高。同一功能群内各层植物光饱合点在1200—1500μmol m^(-2)s^(-1)之间,差别不大。林下灌木、草本植物对弱光的利用效率较乔木高。同一功能群内物种功能性状的差异及不同植物功能群间整体性状的差异,影响着森林生态系统的结构、功能、过程和生态系统服务。
A Plant Functional Group （PFG） is composed of a set of plants co-existing within a community and can serve as a basic unit of vegetation dynamic change within an environment and can act to simplify related research. The physiological characteristics of different species provide the basis for PFG classification and also affect the overall function of PFGs. The forest ecosystem has structural integrity in the National Natural Reserve of FuNiu Mountain. Through species＇ interspecific associations and their dynamic changes along the elevation gradient, we classified the dominant species into four major PFGs. We then analyzed the photosynthetic characteristics of each plant of the four PFGs. Using the photosynthesis system, we measured the photosynthetic characteristics of different plants of PFGs and analyzed and compared the results which show： that the maximum Coefficient of Variation of different species＇ LCP（ light compensation point） and Rd（ respiration rate） was 70.47% and 74.29% respectively within the same PFG; these are complementary to each other among functional traits, which is the main reason for the long-term coexistence of the PFG. Trees＇ Pn （ maximum net photosynthetic rate） was between 7 and 8 CO2m^-2s^-1 which suggests that they have the ability to capture high-intensity light LSP （Light saturated point） within the same PFG was mainly between 1200-1500μmol CO2m^-2s^-1, which differs very little. Herbaceous understoryshrubs are more sensitive to low-intensity light than the trees. There are functional characteristic differences among the same PFG and between different PFGs, which affects the structure, function, processes, and ecosystem services of the forest ecosystem.
出处
《生态学报》
CAS
CSCD
北大核心
2016年第15期4609-4616,共8页
Acta Ecologica Sinica
基金
国家自然科学基金资助项目(41071118
40671175)
