Kolloquium: Bettina Weber

Cryptogamic communities (CC) are composed of photosynthesizing cyanobacteria, algae, lichens, and bryophytes, accompanied by heterotrophic bacteria, microfungi, archaea, and a diverse microfauna. They colonize rocks, soil and grow epiphytically on the bark and sometimes even the leaves of trees. Despite their small size and often inconspicuous habitus, research has revealed their key relevance in ecosystems and Earth system processes. In my talk, I will first introduce how CC could be mapped and monitored in different ecosystems, analyzing unmanned aerial vehicle imagery by means of deep learning methods. In a second part, I will illustrate their role in global biogeochemical processes, namely nitrogen cycling, the emission of volatile organic compounds and atmospheric aerosol cycling. In a final section, I will elucidate their sensitivity to climate change as observed both in modeling and experimental approaches.Overall, our studies show that CC are relevant in various global processes, which up to now have not or only barely been considered. These mechanisms need to be included in global modeling approaches to obtain a more thorough understanding of the processes and drivers and to evaluate the role of CC in current and future environmental scenarios.