DataSheet_1_Effects of chicken manure substitution for mineral nitrogen fertilizer on crop yield and soil fertility in a reduced nitrogen input regime of North-Central China.pdf

Organic manure has been proposed to substitute part of the chemical fertilizers. However, past research was usually conducted in regimes with excessive nitrogen (N) fertilization, which was not conducive to the current national goal of green and sustainable development. Therefore, exploring the potential of organic fertilizer substitution for mineral N fertilizer under regimes with reduced N inputs is important to further utilize organic fertilizer resources and establish sustainable nutrient management recommendations in the winter wheat (Triticum aestivum L.) – summer maize (Zea mays L.) rotation system in North-central China. In this study, a 4-year field experiment was conducted to investigate the effects of different chicken manure substitution ratios on crop yield, N recovery efficiency (REN), soil N and soil organic matter contents, to clarify the optimal organic substitution ratio of N fertilizer under reduced N application (from 540 kg N ha−1 year−1 to 400 kg N ha−1 year−1). Six substitution ratios were assessed: 0%, 20%, 40%, 60%, 80% and 100% under 200 kg N ha−1 per crop season, respectively, plus a control with no N application from chemical fertilizer or chicken manure. Results showed that the highest yield was achieved under the 20% substitution ratio treatment, with 1.1% and 2.3% higher yield than chemical N alone in wheat season and maize seasons, respectively. At the chicken manure substitution ratios of 20% in wheat season and 20%-40% in maize season, the highest REN reached to 31.2% and 26.1%, respectively. Chicken manure application reduced soil residual inorganic N with increasing substitution ratio. All organic substitution treatments increased soil organic matter and total N content. Implementing 20% organic substitution in wheat season and 20%-40% in maize season under the reduced N application regime in the North-central China is therefore recommended in order to achieve high crop yields and REN, improve soil fertility and enhance livestock manure resource utilization.

有机肥替代部分化肥已成为农业领域的重要研究方向。然而过往相关研究多在高氮施肥模式下开展，这与我国当前绿色可持续发展的国家目标不符。因此，在华北中北部冬小麦（Triticum aestivum L.）-夏玉米（Zea mays L.）轮作系统中，探究减氮模式下有机肥替代矿质氮肥的潜力，对于进一步盘活有机肥资源、制定可持续养分管理方案具有重要意义。本研究依托为期4年的田间试验，设置不同鸡粪替代氮肥比例处理，探究其对作物产量、氮素回收率（REN）、土壤氮素及土壤有机质含量的影响，旨在明确减氮模式下（施氮量从540 kg N·ha⁻¹·a⁻¹降至400 kg N·ha⁻¹·a⁻¹）氮肥的最优有机肥替代比例。本试验设置6个替代比例梯度：每个作物季施氮量为200 kg N·ha⁻¹时，替代比例分别为0%、20%、40%、60%、80%和100%，另设不施用化肥氮肥与鸡粪的空白对照处理。试验结果表明，20%替代比例处理下作物产量最高，小麦季与玉米季产量分别较纯施化学氮肥处理提升1.1%与2.3%。当小麦季鸡粪替代比例为20%、玉米季为20%~40%时，氮素回收率分别达到峰值31.2%与26.1%。随着鸡粪替代比例提升，土壤残留无机氮含量呈下降趋势。所有有机肥替代处理均可提升土壤有机质与全氮含量。综上，华北中北部减氮模式下，建议小麦季采用20%有机肥替代比例，玉米季采用20%~40%有机肥替代比例，以实现作物高产与高氮素回收率、提升土壤肥力并强化畜禽粪肥资源的资源化利用。