Long-term field experiment finds that one-third sheep manure reduces N2O emissions in maize systems, indicating effective organic substitution.
Key Points
This research aims to examine how substituting chemical nitrogen fertilizers with organic amendments affects N2O emissions and microbial activity in maize cropping systems.
Conducted a long-term field experiment in maize cropping systems
Monitored in situ N2O flux and performed soil analysis
Employed metagenomic sequencing to analyze microbial communities
Tested varying ratios of sheep manure substitution for chemical N fertilizers
One-third substitution of chemical N with sheep manure reduced N2O emissions by 18.64% in 2021 and 47.00% in 2022
Soil nitrate and ammonium concentrations significantly decreased
Soil organic matter increased with organic substitution
Enhanced abundance of denitrification-related genes was observed
Partial least squares path modeling indicated soil properties indirectly reduced N2O emissions through microbial community regulation