Mosses – underestimated climate indicators? An international team of researchers led by the botanist Dr Thomas Kiebacher from the Natural History Museum Stuttgart addressed this question. Over a period of 20 years, they studied whether mosses react differently to the climate crisis than the more complex ferns and flowering plants. For this purpose, they analysed the composition of the plant communities on over 1000 sampling sites throughout Switzerland between 2001 and 2021.
Generally, as temperatures in their habitats rise, plants tend to “move” to cooler regions or higher altitudes – of course not the individuals themselves but their descendants. In mountain ranges, however, this can only work up to a certain point: the summit. Beyond that, there are no more possibilities of escape, and the plants face the threat of extinction.
The long-term study's conclusion: mosses are truly sensitive plants! Driven by rising temperatures, they "climb" uphill about twice as fast as flowering plants and ferns. Mosses, therefore, react much more sensitively to climatic changes. Therefore, Mosses react much more sensitively to climate changes. Although this gives them an advantage in the short term, their sensitivity poses a threat in the medium run. Mosses at extreme altitudes are already acutely threatened with extinction, as they cannot escape further upwards - a situation that many other species will face in the near future.