Effects of emergent aquatic plants on nitrogen transformation processes and related microorganisms in a constructed wetland in northern China

Aims Wetland plants affect ammonia-oxidation rate (AOR) and nitrogen-fixation rate (NFR), resulting in changes in plant-available nitrogen and wetland nitrogen-cycling. This study aims to investigate the underlying mechanisms and influencing factors associated with ammonium oxidation and nitrogen fixation in response to wetland-emergent aquatic plants.