Without any root contact with the soil, epiphytic bryophytes must experience and explore poor, patchy, and heterogeneous habitats; while, the nitrogen (N) uptake and use strategies of these organisms remain uncharacterized, which obscures their roles in the N cycle. To investigate the N sources, N preferences, and responses to enhanced N deposition in epiphytic bryophytes, we carried out an in situ manipulation experiment via the ¹⁵N labelling technique in an Asian cloud forest. Epiphytic bryophytes obtained more N from air deposition than from the bark, but the contribution of N from the bark was non-negligible. Glycine accounted for 28.4% to 44.5% of the total N in bryophyte tissue, which implies that organic N might serve as an important N source. Increased N deposition increased the total N uptake, but did not alter the N preference of the epiphytic bryophytes. This study provides sound evidence that epiphytic bryophytes could take up N from the bark and wet deposition in both organic and inorganic N forms. It is thus important to consider organic N and bark N sources, which were usually neglected, when estimating the role of epiphytic bryophytes in N cycling and the impacts of N deposition on epiphytic bryophytes in cloud forests.

As heterotrophic respiration (R_H) has great potential to increase atmospheric CO₂ concentrations, it is important to understand warming effects on R_H for a better prediction of carbon–climate feedbacks. However, it remains unclear how R_H responds to warming in subtropical forests. Here, we carried out trenching alone and trenching with warming treatments to test the climate warming effect on R_H in a subtropical forest in southwestern China. During the measurement period, warming increased annual soil temperature by 2.1 °C and increased annual mean R_H by 22.9%. Warming effect on soil temperature (WE_T) showed very similar pattern with warming effect on R_H (WE_RH), decreasing yearly. Regression analyses suggest that WE_RH was controlled by WE_T and also regulated by the soil water content. These results showed that the decrease of WE_RH was not caused by acclimation to the warmer temperature, but was instead due to decrease of WE_T. We therefore suggest that global warming will accelerate soil carbon efflux to the atmosphere, regulated by the change in soil water content in subtropical forests.