Comparison on the competitiveness of the invaded pokeweed with its accompanying species in the coastal protection forest of Shandong Peninsula

[Objective]Pokeweed ( Phytolacca americana ) is an invasive plant specie sand now widely distributed in China. This paper explores the ecophysiological mechanism of pokeweed invasion and its advantages over the accompanying species in terms of their energy use efficiency,and usage of water,nitrogen and other resources,in order to provide a reference for risk assessment of pokeweed and the comprehensive prevention and control. [Method]This experiment was performed in the coastal protection forest belt in northern Yantai. In this study,the photosynthetic performance parameters of pokeweed and its accompanying species Amorpha fruticosa at the margins of the forest were measured with a TPS -1 photosynthetic system under both low and high light environment to study the ecophysiological mechanism of invasion. Light use efficiency and water use efficiency were calculated according to the related parameters. The chlorophyll fluorescence parameters were detected by using a Handy-PEA system. The total nitrogen content