Çin'in Kara Toprak Bölgesinde Sürdürülebilir Mısır İçin Azot Optimizasyonu

Özet (abstract)

The black soil region of Northeast China is a major grain-producing area, where excessive nitrogen (N) fertilizer application is common in maize production. Optimizing N application rates and developing fertilization strategies that balance high yield, N-use efficiency, and environmental sustainability are therefore critical for green maize production. Based on a two-year stationary field experiment, this study systematically evaluated the effects of different N application rates on maize yield, N-use efficiency, N cycling and balance within the soil–crop system, and greenhouse gas emissions from farmland. Four treatments were established: no N control (N0, 0 kg N ha−1), low N (N1, 120 kg N ha−1), medium N (N2, 180 kg N ha−1), and high N (N3, 240 kg N ha−1). Among the N-fertilized treatments, N2 provided the best overall balance between maize yield, N-use efficiency, and environmental performance; N1 failed to achieve the high-yield target, whereas N3 increased potential environmental risks despite further yield gains. Compared with N1 and N3, N2 increased maize yield by 14.6% and 4.1%, N recovery efficiency (NRE) by 2.6% and 26.8%, and N agronomic efficiency (NAE) by 9.8% and 51.8%, respectively. Although N1 exhibited the highest partial factor productivity of applied N (PFPN), its PFPN was 27.2% and 68.7% higher than those of N2 and N3, respectively. Increasing N application significantly increased soil N residues and greenhouse gas emissions. After the 2025 autumn harvest, mineral N residues in the 0–80 cm soil profile were 82.7, 138.9, 172.5, and 207.9 kg N ha−1 under N0, N1, N2, and N3, respectively, and declined with soil depth. Compared with N3, N2 reduced apparent N loss, soil mineral N residue, apparent N surplus, nitrous oxide (N2O) and carbon dioxide (CO2) efflux by 47.8%, 17.0%, 26.2%, 25.5%, and 23.1%, respectively. Collectively, these results provide a theoretical and technical basis for high-yield, high-efficiency, and sustainable maize production in the black soil region of Heilongjiang Province.

Yazarların özeti; kaynağından alınmıştır. Agronomy, 2026 · DOI ↗