SP03c Functional diversity in a subtropical forest based on ecophysiological species traits (FOR891_sp03c traits)

The main objective of the Chinese twin subproject 3 at the second stage is to study China’s subtropical forest plants’ functional diversity focusing on the plants’ ecophysiological traits, as well as on some morphological traits. We will achieve this goal by participating in investigations in both the Comparative Study Plots at Gutianshan (Zhejiang) and the Main Experimental Plot at Xinggangshan (Jiangxi). Based on our investigation at the permanent plot at Gutianshan in the past two years, we will test how the variation in micro-site and soil characteristics affect ecophysiological and morphological traits and compare the functional diversity among different habitats in a subtropical evergreen broad-leaved forest. The results provide evidence that at the regional scale especially elevation and convexity are the two most important topographical factors that affect functional traits. The most powerful soil characteristics are moisture and nitrogen content. At the second stage, we will continue to study forest tree species’ function traits at the permanent plot of Gutianshan focusing on their underground processes, e.g. architecture and dry matter formation of coarse roots. We also want to check if the response patterns of tree species’ ecophysiological traits to microenvi-ronmental changes still exist in the CSPs. With the development of the seedlings in the Main Experiment plots, we will contribute to investigating the functional traits in response to species richness and environmental changes. We will focus on plant’s ecophysiological traits using the approaches of in situ gas exchange, chlorophyll fluorescence and in vivo biochemistry. The measurements will comprise e.g. maximum photosynthetic rate, stomatal conductance, transpiration rate, water use efficiency, stem sapwood xylem specific hydraulic conductivity, shoot water potential, respiration, light compensation/saturation point, maximum carboxylation rate, maximum photosynthetic electron rate, PSII efficiency.