Bilateral DFG project (D/CZ): "Linking microclimate, deadwood microbial diversity, adaptation mechanisms and ecosystem processes (MicroLink)"

2021-2025, Friederike Roy & Harald Kellner, together with partners from the Czech Academy of Sciences in Prague

Deadwood-dependent fungi and bacteria are among the most species-rich groups of organisms in forests and contribute significantly to the stability and function of corresponding ecosystems, as they play a major role in the decomposition of organic matter. So far, most studies have focused on the relationship between fungal and bacterial diversity and resource- and host-specific factors, such as deadwood volume or tree species identity. However, our understanding of how abiotic factors such as microclimate influence wood-dependent communities and associated ecosystem processes, including decomposition, is still rudimentary. In addition, potential adaptation mechanisms of microorganisms to changing microclimatic conditions are still poorly understood.

Currently, our forests are affected by climate-induced crown dieback to an unprecedented extent and over a large spatial and geographical area, which is changing the microclimate in forest ecosystems. Microclimatic changes also take place in the context of regular forestry management through logging and associated interventions in the canopy. In order to improve predictions and develop measures to mitigate the effects of climate change, we need a better understanding of the relationships between microclimate, wood-dependent biodiversity and the associated decomposition processes.

In this context, we use an existing, large-scale, long-term experiment on deadwood decomposition in the Bavarian Forest and have integrated another, newly designed experiment there to test hypotheses about the influence of microclimate on the assembly mechanisms of fungal and bacterial communities, resulting diversity patterns and associated decomposition processes. In particular, molecular methods are used to characterize fungal and bacterial communities and to learn more about their adaptation mechanisms. Our results should support the development or improvement of forest management concepts and help to find a balance between wood production and biodiversity in the forest. This is particularly important in the context of global change, the increasing frequency and intensity of climate-related disturbance events and the ongoing discussions on climate-resilient, sustainable forestry.