Reactive nitrogen restructures and weakens microbial controls of soil N₂O emissions.

ABSTRACT: The global surplus of reactive nitrogen (N_r) in agricultural soils is accelerating nitrous oxide (N₂O) emission rates, and may also strongly influence the microbial controls of this greenhouse gas resulting in positive feedbacks that further exacerbate N₂O emissions. Yet, the link between legacy effects of N_r on microbial communities and altered regulation of N₂O emissions is unclear. By examining soils with legacies of N_r-addition from 14 field experiments with different edaphic backgrounds, we show that increased potential N₂O production is associated with specific phylogenetic shifts in communities of frequently occurring soil microbes. Inputs of N_r increased the complexity of microbial co-association networks, and altered the relative importance of biotic and abiotic predictors of potential N₂O emissions. Our results provide a link between the microbial legacy of N_r addition and increased N₂O emissions by demonstrating that biological controls of N₂O emissions were more important in unfertilized soils and that these controls are weakened by increasing resource levels in soil.

SUBMITTER: Jones CM 

PROVIDER: S-EPMC8960841 | biostudies-literature | 2022 Mar

REPOSITORIES: biostudies-literature