Abstract: Bryophytes are primary producers in crucial global ecosystems, significantly contributing to carbon cycling through photosynthesis. Systematic understanding of photosynthesis of bryophytes and influencing factors will provide new perspectives and pathways for the ecosystem carbon cycling and carbon neutrality. However, current research on photosynthesis of bryophytes and its influencing factors remains poorly studied. Based on systematic literature search and analysis, this review indicates a mean maximum net photosynthetic rate (A_max) of 29.61 nmol CO₂ g^-1 s^-1 in bryophytes, about 20% of that in vascular plants, showing significant interspecific differences and intraspecific variations. Mass-based Amax follows the order: Thalloid liverworts > Acrocarpous mosses > Pleurocarpous mosses > Sphagnum mosses > Leafy liverworts. Key factors regulating bryophyte photosynthetic capacity are examined, including plant structure and morphology, anatomical features (e.g., cell wall thickness), environmental factors (light, water, temperature), and colony structure (numerical density, colony mass per unit area, leaf area index). Future studies are needed to investigate: (1)how photosynthetic capacity varies across the phylogenetic spectrum of bryophytes; (2) how the mechanisms underlying colony structure influence bryophyte photosynthesis can be determined; (3)how the interactive effects of multiple factors on bryophyte photosynthesis can be studied; and (4)how bryophyte photosynthesis and carbon sequestration potential vary across large spatiotemporal scales.

Key words: bryophytes, net photosynthetic rate, colony numerical density, photosynthesis, carbon cycling