Soil hydrology drives ecological niche differentiation in a native prairie microbiome

As precipitation patterns are altered by climate change, understanding the impact of soil hydrology on community structure and function is critical. In this work, soil inundation was continuously monitored for over a year in an undisturbed Midwestern tallgrass prairie at 10 cm depth increments up to a depth of 120 cm in 11 wells using a recently developed field-scale sensor network. We analyzed microbiome composition and edaphic factors analysis at each well and depth increment in the context of this unique longitudinal dataset. We demonstrate that total inundation duration can explain more of the variation in diversity and composition across this site than sample depth or pH. In addition, we use regularized regression and variance partitioning approaches to quantify the impact of soil hydrology on community structure in the context of multiple collinear predictors, and find that inundation is a stable predictor of both community diversity and composition. Lastly we show that these compositional changes influence ammonia oxidizer abundance and predicted nitrogen cycling functional gene abundance.