College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, China; Yanshan Earth Critical Zone National Research Station, University of Chinese Academy of Sciences, Beijing, China; Key Laboratory of Adaptation and Evolution of Plateau Biota, Chinese Academy of Sciences, Xining, China
Shutong Zhou
College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, China
Kui Wang
College of Life Sciences, University of Chinese Academy of Sciences, Beijing, China
Wenjing Liu
College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, China
Cong Xu
State Key Laboratory of Remote Sensing Science, Aerospace Information Research Institute, Chinese Academy of Sciences, Beijing, China
Lizhen Cui
College of Life Sciences, University of Chinese Academy of Sciences, Beijing, China
Linfeng Li
College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, China; Environmental Futures Research Institute, School of Environment and Science, Griffith University, Nathan, Australia
Qinwei Ran
College of Life Sciences, University of Chinese Academy of Sciences, Beijing, China
Zongsong Wang
College of Life Sciences, University of Chinese Academy of Sciences, Beijing, China
College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, China; Yanshan Earth Critical Zone National Research Station, University of Chinese Academy of Sciences, Beijing, China
Yanbin Hao
Yanshan Earth Critical Zone National Research Station, University of Chinese Academy of Sciences, Beijing, China; College of Life Sciences, University of Chinese Academy of Sciences, Beijing, China
Xiaoyong Cui
Yanshan Earth Critical Zone National Research Station, University of Chinese Academy of Sciences, Beijing, China; College of Life Sciences, University of Chinese Academy of Sciences, Beijing, China
College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, China; Yanshan Earth Critical Zone National Research Station, University of Chinese Academy of Sciences, Beijing, China; State Key Laboratory of Tibetan Plateau Earth System Science (LATPES), Beijing, China
Though being fundamental to global diversity distribution, little is known about the geographic pattern of soil microorganisms across different biotas on a large scale. Here, we investigated soil prokaryotic communities from Chinese northern grasslands on a scale up to 4000 km in both alpine and temperate biotas. Prokaryotic similarities increased over geographic distance after tipping points of 1760–1920 km, generating a significant U-shape pattern. Such pattern was likely due to decreased disparities in environmental heterogeneity over geographic distance when across biotas, supported by three lines of evidences: (1) prokaryotic similarities still decreased with the environmental distance, (2) environmental selection dominated prokaryotic assembly, and (3) short-term environmental heterogeneity followed the U-shape pattern spatially, especially attributed to dissolved nutrients. In sum, these results demonstrate that environmental selection overwhelmed the geographic ‘distance’ effect when across biotas, overturning the previously well-accepted geographic pattern for microbes on a large scale.
