ABSTRACT

Soil nitrogen (N) distribution and crop utilization are closely related to fertilizer management and crop productivity. The present study, based on 47-year fertilizer focused on a cropping system (maize-wheat) based budgeting of N which is necessary to identify its sources and losses to improve fertilizer use efficiency, crop productivity, and environmental sustainability. Long-term application of fertilizer has a positive effect on soil TN (total nitrogen) and TOC (total organic carbon), which increased by 36–107% and 24–103%, respectively compared to control. Integrated application of fertilizer and farmyard manure registered 266% higher grain yield of maize-wheat over the control but the addition of 50% higher NPK than recommended NPK showed no yield advantage and reduced recovery of fertilizer N by 23% (maize) and 22% (wheat) relative to NPK. Accounting all the N inputs and outputs, NPK application (least N loss) has 49–85 kg ha⁻¹ lower N loss compared to NP and N application, respectively. It has concluded that the long-term use of recommended and balanced fertilizer alone or in combination with FYM has the potential to improve N and C status of soil and its recovery by decreasing its loss, which increases the productivity of the maize-wheat system.

摘要

土壤氮（N）分布和作物利用与肥料管理和作物生产力密切相关。本研究基于 47 年的肥料，重点关注基于 N 的种植系统（玉米-小麦）预算，这是确定其来源和损失以提高肥料使用效率、作物生产力和环境可持续性所必需的。长期施肥对土壤 TN（总氮）和 TOC（总有机碳）有积极影响，与对照相比分别增加了 36-107% 和 24-103%。肥料和农家肥的综合施用使玉米-小麦的产量比对照高 266%，但添加比推荐的 NPK 高 50% 的 NPK 显示没有产量优势，肥料 N 的回收率降低了 23%（玉米）和 22% （小麦）相对于 NPK。与 NP 和 N 应用相比，N 损失分别为^{-1 。}结论是，长期单独使用推荐的平衡肥料或与 FYM 结合使用，有可能通过减少土壤的损失来改善土壤的 N 和 C 状态及其恢复，从而提高玉米-小麦系统的生产力。