Responses of terrestrial bryophytes to simulated climate change in a secondary evergreen broad-leaved forest in southern China

Tropical regions are biodiversity hotspots and are well-suited to explore the potential influence of global climate change on forest ecosystems. Bryophytes have essential ecological functions in tropical forest ecosystems, but knowledge of the potential impact of global warming and possible changes in water availability patterns on terrestrial bryophytes is limited. We transplanted eight terrestrial moss species from two elevations (900 and 500 m) to warmer and drier elevations (500 and 100 m) during a half-year observation period on Tai Mo Shan, southern China. The simulated climate change resulted in severely declined health status and marked decrease in growth of the transplanted species when compared with their performance at the original elevations. Five of the eight selected species survived for six months after being transplanted to the warmer and drier lowlands, though their health status deteriorated severely. Sematophyllum subhumile, Pseudotaxiphyllum pohliaecarpum and Brachythecium buchananii were highly susceptible to changes in temperature and rainfall patterns and might be used as suitable bioindicators. As the tropics are expected to become hotter and drier, terrestrial mosses might be negatively affected or even be at risk of extinction. Bryophytes in the tropics could represent one of the best biological communities to reflect the direct adverse impact of climate change and provide early warning of the biological outcomes induced by ongoing climate crisis.