Azorella Cushion Plants and Aridity are Important Drivers of Soil Microbial Communities in Andean Ecosystems

15 páginas.- 4 figuras.- 2 tablas.- 96 referencias.- Supplementary information: The online version contains supplementary material available at (https://doi.org/10.1007/s10021-021- 00603-1)

Cushion plants are specialized keystone species of alpine environments that can have a positive effect on ecosystem structure and function. However, we know relatively little about how cushion plants regulate the diversity and composition of soil microbial communities, major drivers of soil processes and ecosystem functioning. Identifying what factors drive the diversity and composition of soil microbial communities in high-elevation ecosystems is also fundamental to predict how global changes will affect their conservation and the services and functions they provide. Thus, we sampled four sites along the southern Andes following the vegetation belt of Azorella cushion species. The field sites spread along a latitudinal gradient and had contrasting levels of aridity, UV-B radiation, mean temperature and soil properties. Overall, Azorella, as well as aridity and UV-B radiation, were the major drivers of the distribution, composition and diversity of soil microbial communities in the studied ecosystems of the Chilean Andes. UV-B radiation affected particularly soil fungi, while soil properties such as pH, total C and N content, essential predictors of microbial diversity globally, had a much lower effect on the composition of soil microbial communities. Understanding the factors driving the structure and composition of microbial communities, particularly the role of cushion plants and the feedbacks between plant, climate and soil is of uttermost importance for the preservation of the functionality of high-elevation ecosystems threatened by climate change. © 2021, The Author(s), under exclusive licence to Springer Science+Business Media, LLC part of Springer Nature.

S.R-E. was supported by a Research Grant from the Portuguese Foundation for Science and Technology–FCT (IF/00462/2013) and by a scholarship from the program “Bolsas Iberoamericanas—Santander Universidades” from Banco Santander-Totta. C.A. was supported by the Spanish Government under a Ramón y Cajal contract (RYC-2012-12277) and work in Chile was funded by the LincGlobal program. Further support was provided by the Spanish AEI (grants CGL2014-59010-R to C.A. and F.I.P. and CGL2017-84515-R to F.I.P). M.D-B. was supported by a Ramón y Cajal grant from the Spanish Ministry of Science and Innovation (RYC2018-025483-I). A.G., L.A.C. and P.A.M acknowledge support from CONICYT-Associative Research Program AIC-37 and AFB170008 from Instituto de Ecología y Biodiversidad. A.G. and L.A.C were also supported by Fondecyt 1110063 and Fondecyt 1171005, respectively. We also thank Dr. Luis Javier Martinez and Belén Martínez García for the implementation of protocols for molecular microbial analysis at GENYO (Granada, Spain).

Peer reviewed