Microclimate determines the diversity patterns, biomass, and water storage capacity of bryophytes in the alpine...

The majority of studies on alpine vegetation have focused on higher plants, while relatively little is known about how lower plants, such as bryophytes, respond to microclimate in the alpine ecosystem. Microclimate critically influences the distribution and growth of bryophytes in alpine ecosystems, and therefore, understanding the functional role of microclimate on bryophyte's physiological adaptation is critical for understanding the climate change response. To fill this knowledge gap, the present study investigated the patterns of species richness, biomass accumulation, and water storage capacity in bryophytes in alpine ecosystems of the Kashmir Himalaya. We conducted stratified systematic field sampling of bryophytes in two major alpine vegetation zones: open meadow above the timberline (AT) and under forest canopy cover below the timberline (BT) in Kashmir Himalaya, along with measurement of five microclimate variables: photosynthetically active radiation (PAR, µmol m^-2 s^-1), air temperature (AT, °C), soil temperature (ST, °C), ambient CO₂ concentration (μmol mol^-1), and absolute humidity (AH, mmol mol^-1). We found a total of 30 bryophyte species, including 3 liverworts and 27 mosses in the two zones with 10 species common. AT zone with greater species richness and more homogenous distribution of bryophytes exhibited higher biomass. Canonical correspondence analysis (CCA) identified PAR and air temperature (AT) as key microclimatic drivers influencing community structure, biomass accumulation, and water storage capacity in above the timberline, while humidity (AH) emerged as the primary factor shaping bryophyte dynamics in below the timberline. This study provides an insight into the ecological dynamics of bryophyte communities and relationships among microclimates with community structure, biomass, and water storage capacity of bryophytes in alpine ecosystems and highlights the need for continuous long-term monitoring to unravel these complex interactions.