Effects of groundwater depth and nitrogen application on nirS and nirK

Depression of groundwater table and reduced nitrogen application not only directly altered the species composition of denitrifier bacterial communities, but also indirectly influenced it through regulating soil nutrient and salinity. Furthermore, the variation in soil nitrate nitrogenand electrical conductivity caused by depression of groundwater table and reduced nitrogen application plays the most important role in altering the community composition of denitrifier bacterial communities.