Conversion of upland to paddy alters the spatial distribution and abundance of microorganisms involved in the soil nitrogen cycle

Microorganisms are pivotal in regulating the soil nitrogen cycle (N-cycling). However, a significant gap in knowledge exists concerning changes in gene abundance and microbial communities driving this cycle. This gap is pronounced in the spatial distribution of land use in the northeastern black soil zone in northeast China, where nitrogen limits productivity. Hence, we explored bacterial-mediated nitrogen cycling in converted Mollisols, transitioning from upland to paddy fields. We assessed functional gene abundances and key functional groups through quantitative polymerase chain reaction (qPCR) and Miseq sequencing, respectively.