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

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 (Anmax−L), light saturation point (Isat), light compensation point (Ic) and dark respiration rate (Rd) wereca0.55, 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 chlorophyllato chlorophyllb(Chla/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. [ABSTRACT FROM AUTHOR]