Bryophytes, one of the moss groups, have many ecosystem services (e.g., thermal mitigation, rainwater storage, biodiversity enhancement, etc.) and are used as vegetation plants for urban roof and wall greening due to their high durability against harsh environments such as urban heat and drought. Although the artificial introduction of bryophytes into cities has been actively studied, the ecosystem services provided by wild bryophytes in urban areas have not been well studied. Wild bryophytes in urban green spaces and natural grasslands are known to contribute to ecosystem services, but information on bryophytes on asphalt and concrete is lacking.
To quantify the ecosystem services provided by wild bryophytes, especially on asphalt and concrete in urban areas, we investigated basic information on urban bryophytes, such as “how abundant is wild bryophytes in urban areas” and “what environmental factors affect their distribution”, in Sapporo, Hokkaido, Japan in this research.
First, we collected the bryophytes distribution and biomass data in field areas to clarify bryophyte biomass in urban areas. For this study, one count of a bryophyte colony was defined as 3 x 3 cm. Second, we built models for bryophyte distribution using urban micro-physical environmental factors (wall directions, sunlight intensity, artificial objects on walkways, roadside trees) and liverwort distribution to investigate the importance of urban environmental factors. The models were built using methods such as GLM, GAM, and RF based on the general species distribution models (SDMs) method. These models had sufficient accuracy (all of AUC was more than 0.75). According to these models, the directions of walls, sunlight intensity, and artificial medium size objects like electric poles  have a larger effect on the bryophyte distributions compared  to the other factors.
Our results suggest that bryophytes are generally distributed in the urban area of Sapporo, and that the distribution of bryophytes is affected by the presence of artificial structures such as buildings and electric poles. The results of this study, combined with future research to quantify the ecosystem services provided by urban bryophytes, will enable us to evaluate the ecosystem services provided by urban bryophytes on a whole-city scale.