Adaptation of epiphytic bryophytes in the understorey attributing to the correlations and trade-offs between functional traits

Abstract

This study explores adaptive strategies of epiphytic bryophytes in the understorey by investigating the photosynthetic characteristics, pigment concentrations and nutrient stoichiometry, as well as other functional traits of three trunk-dwelling bryophytes in a subtropical montane cloud forest in SW China. The results showed that their light-saturated net photosynthetic rate (A_nmax−L), light saturation point (I_sat), light compensation point (I_c) and dark respiration rate (R_d) were ca 0.55, 106.72, 4.17 and 0.25 μmol m⁻² s⁻¹, respectively. Furthermore, the samples demonstrated photosynthetic down-regulation under high irradiance. These photosynthetic characteristics can be explained by higher total chlorophyll concentrations, specific leaf area, chlorophyll per unit leaf N (Chl/N), lower ratio of chlorophyll a to chlorophyll b (Chl a/b) and photosynthetic nitrogen-use efficiency. We suggest that the bryophytes adapted to the shaded understorey microhabitats through a series of correlations and trade-offs between functional traits.

Keywords:

• Correlation
• Epiphytic bryophyte
• Functional trait
• Trade-off
• Understorey

Acknowledgements

We would like to thank Mr Xin Luo for his assistance in fieldwork. Thanks are also due to Wenzhang Ma and Jiaolin Zhang for their helpful work. This study was funded by the National Natural Science Foundation of China (No. U1133605, 41471050, 31300382). We also thank the Management Authority of the Ailao Mountains National Nature Reserve and the Ailao Mountains Subtropical Forest Ecosystem Research Station for granting permission and facilitating this research.

Taxonomic Additions and Changes: Nil.