Wheat/pea intercropping with reduced nitrogen inputs maintains crop productivity but lowers soil nitrate residues and N2O emissions: Evidence at crop and cropping system levels
Li, GG; Liu, JL; Yao, JF ; TK ; Xiao, JK ; Nangia, V ; Liu, Y
AGRICULTURE ECOSYSTEMS & ENVIRONMENT
DOI：10.1016/j.agee.2026.110354
Abstracts：
Cereal-legume intercropping is a promising strategy for enhancing agricultural productivity while reducing nitrogen (N) fertilizer inputs. However, the extent to which intercropping systems combined with optimized N input can simultaneously deliver high agronomic productivity, low environmental impact, and favorable economic performance remains insufficiently resolved. To address this issue, a two-year field experiment involving wheat monoculture, pea monoculture, and wheat/pea strip intercropping was conducted under crop-specific N application rates. Wheat received 0, 180, and 240 kg N ha-1, pea received 0, 90, and 135 kg N ha-1, with the same crop-specific N rates used in both monoculture and intercropping. The results demonstrated that wheat/pea intercropping significantly increased system grain yield (13.03%), N uptake (8.67%), and N use efficiency (8.50%) compared with the monoculture-based predicted values. This intercropping system also reduced overall soil nitrate N residues and nitrous oxide emissions by 8.29% and 6.62%, respectively. In addition, the inter-cropping system generated the highest net economic benefit at 135 kg N ha-1. These advantages were predominantly driven by the wheat component. A comprehensive evaluation further revealed that wheat/pea strip intercropping combined with 135 kg N ha-1 exhibited the best system performance in terms of agronomic productivity, reduced environmental impacts, and economic performance. Collectively, these findings suggest that this intercropping-N management strategy can simultaneously enhance food security, boost farmers' economic returns, and mitigate environmental pressures in the Guanzhong Plain, offering a short-term pathway to improve cropping system sustainability.