COS 256-3 - CANCELLED - Dynamics of change rate of functional diversity along a secondary succession of a cool temperate forest

Abstract: Although successional changes in the functional diversity of plant communities have been reported, what processes drive the changes is unclear. Based on the data sets of a long-term tree census along a secondary succession we explored a detailed pattern of functional diversity and its change rate along a secondary succession. Data from more than 30 years of observations in plots in secondary forest stands with a wide range of stand ages was used to test the changes in the species diversity, community-weighted means (CWM) of each trait, functional diversity, and their change rates. Although species diversity decreased constantly with the stand age, functional diversity (Rao’s Q) of all traits was significantly decreased at the mid-successional stage, corresponding to the stem exclusion stage. Changes in CWMs of traits indicated the directional shifts of species composition from resource-acquisitive to resource-conservative along succession, especially at the stem exclusion stage. Although the functional diversity of each trait changed differently along succession, those of several resource-conservative traits decreased significantly at the stem exclusion stage. Based on the long-term and multiple chronosequence resampling, we found that the stem exclusion process drove the significant decrease in functional diversity along a secondary succession of cool temperate forests.