生物炭施用量对旱作覆膜农田玉米水氮利用效率及产量的影响OA

[Objectives]This study aimed to investigate the effects of long-term application of different biochar rates on farmland water use efficiency(WUE),nitrogen use efficiency(NUE),and maize yield under different cropping patterns in the dryland area of the Loess Plateau,and to provide a scientific basis for sustainable crop production in mulched farmlands of arid regions.[Methods]Based on a long-term field experiment initiated in 2019,two cropping patterns were established:flat planting without mulching(F)and ridge-furrow planting with film mulching(D).Under each pattern,four biochar application rates were applied:0(CK),3000(L),6000(M),and 9000 kg/hm2(H),resulting in eight treatments.Soil water content(0-200 cm),soil nitrogen nutrients(0-60 cm),maize yield,WUE,and NUE were measured from 2022 to 2023.[Results]Under both cropping patterns,the high-rate biochar treatment(H)optimized WUE,NUE,and maize yield.Ridge-furrow mulching(D)outperformed flat planting(F)at the same biochar rate.Specifically,compared with the FH,DH treatment increased soil water content,soil water storage,and WUE by an average of 10.19%,8.96%,and 24.71%,and enhanced soil total N and NUE by 10.38%and 52.17%,respectively.Mulching combined with biochar significantly enhanced dry matter accumulation in maize organs and yield,with synergistic effects escalating at higher biochar rates.Under ridge-furrow mulching,DH increased yield by 2274 and 2258 kg/hm2,compared to DCK and FH treatment,respectively.[Conclusions]Ridge-furrow mulching combined with biochar application can effectively improve field water and nitrogen use efficiency in maize production.A biochar application rate of 9000 kg/hm2 is recommended to achieve high water and nitrogen utilization and maize yield,thereby supporting sustainable agricultural development in arid regions.