Labile carbon of manure-based biochar accelerates soil denitrification process and increases N2O emission

摘要

The responses of N2O emissions and microbial N cycling community to the application of manurebased biochar remain unknown.We produced a variety of manure biochars with contrasting organic matter availability.Biochars with relatively high labile C content increased the abundance of denitrification genes,i.e.nirK and nosZ,and consequently increased N2O emission,compared to biochars with high aromaticity.Thus,the labile carbon fraction of manure biochar can accelerate soil denitrification process and increase N2O emissions,which may offset the carbon sequestration in soil ecosystems.