Moss and underlying soil bacterial community structures are linked to moss functional traits

• Published in: Ecosphere
• Main Authors: Klarenberg, Ingeborg J., Keuschnig, Christoph, Salazar, Alejandro, Benning, Liane G., Vilhelmsson, Oddur, Salazar Villegas, Alejandro
• Other Authors: Faculty of Life and Environmental Sciences, Faculty of Natural Resource Sciences, Agricultural University of Iceland
• Format: Article in Journal/Newspaper
• Language: English
• Published: 2023
• Subjects: carbon; glacier retreat; moss; moss bacterial communities; moss traits; nitrogen; nitrogen fixation; plant–soil–microbe interactions; primary succession; soil; soil bacterial communities; Ecology; Evolution; Behavior and Systematics; Fláajökull; glacier; Iceland
• Online Access: https://hdl.handle.net/20.500.11815/4529; https://doi.org/10.1002/ecs2.4447

Publisher Copyright: © 2023 The Authors. Ecosphere published by Wiley Periodicals LLC on behalf of The Ecological Society of America. Mosses are among the first colonizing organisms after glacier retreat and can develop into thick moss mats during later successional stages. They are key players in N<jats:sub>2</jats:sub> fixation through their microbiome, which is an important process for nutrient buildup during primary succession. How these moss–microbe interactions develop during succession is not well studied and is relevant in the light of climate change and increased glacier retreat. We examined how the bacterial communities associated with two moss species of the genus <jats:italic>Racomitrium</jats:italic> and the underlying soil, as well as moss traits and nitrogen fixation, develop along a successional gradient in the glacier forefield of Fláajökull in southeast Iceland. In addition, we tested whether moss functional traits, such as total carbon (TC) and total nitrogen (TN) contents, moss moisture content, and moss shoot length are drivers of moss and underlying soil bacterial communities. Although time since deglaciation did not affect TN and moss moisture contents, TC and shoot length increased with time since deglaciation. Moss and underlying soil bacterial communities were distinct. While the soil bacterial community structure was driven by moss C/N ratios, the moss bacterial community structure was linked to time since deglaciation, moss C/N ratio, and moss moisture content. Moss N<jats:sub>2</jats:sub>‐fixation rates were linked to bacterial community composition and <jats:italic>nifH</jats:italic> gene abundance rather than moss TN or time since deglaciation. This was accompanied by a shift from autotrophic to heterotrophic diazotrophs. Overall, our results suggest that there is little lateral transfer between moss and soil bacterial communities and that moss traits affect moss and soil bacterial community structure. Only moss bacterial community ...