Forest degradation could affect forest ecosystem functions through changes in functional composition of tree communities. It is therefore important to understand the pattern of functional responses to forest degradation for better predicting the human impacts. Previous studies have often shown that mean trait values shift towards to those related to species’ acquisitive strategies in response to forest degradation. However, many of them were conducted in wet, closed canopy forests where light is a controlling factor, and it remains unclear how communities respond to forest degradation in dry, open canopy forests where light may not be limited.

We compare the functional compositions between primary and secondary forests in four forest types, i.e., Dry Dipterocarp, Mixed Deciduous, Dry Evergreen and Moist Evergreen forests, along a humidity gradient in Thailand. We quantified the community-weighted mean for 9 leaf traits and wood density, and assessed 6 soil properties, light intensity and air temperature. In this talk, I will show the trait spectrum reflecting main trade-off pattern that respond environments during succession across the different forest types.