<b>Management solutions to handle the global-scale reactive nitrogen crisis</b>

<b>Abstract</b>The global reactive nitrogen (Nr) crisis presents a pressing challenge, requiring practices that balance Nr losses and crop productivity. Here, we evaluate the effect of 14 common management practices on Nr losses and crop productivity by reviewing 146 available meta-analyses and conduct a second-order meta-analysis based on 6382 unique primary studies comprising 20,167 paired observations. Results show that while most practices involve trade-offs or insufficient evidence, applications of enhanced-efficiency fertilizers, reduced nitrogen inputs, optimized fertilization methods, and biochar amendments consistently achieve ‘win-win’ outcomes by mitigating Nr losses (N₂O, NO, NH₃ emissions, and leaching/runoff) and improving crop productivity (nitrogen use efficiency, nitrogen uptake, and crop yield). By quantifying the average effect and go beyond qualitative information, we reveal the list of ‘win-win’ practices that facilitate global movements commensurate with reactive nitrogen crisis while trade-offs could be minimized.<b>Keywords</b>: Reactive nitrogen; Second-order meta-analysis, Nitrogen mitigation, Crop productivity, Sustainable agriculture

<b>摘要</b>全球活性氮（Reactive Nitrogen, Nr）危机是一项亟待破解的严峻挑战，亟需探索能够平衡活性氮流失与作物生产力的管理实践。本研究通过梳理146篇已发表的元分析（meta-analysis），评估了14种常见管理措施对活性氮流失与作物生产力的影响，并基于包含20167组配对观测数据的6382项独立原始研究开展了二阶元分析（second-order meta-analysis）。研究结果显示，尽管多数管理措施存在权衡取舍或证据不足的问题，但增效肥料（enhanced-efficiency fertilizers）施用、减少氮素投入、优化施肥方式以及生物炭改良（biochar amendments）这四项措施，均可通过降低活性氮流失（包括N₂O、NO、NH₃排放以及淋溶/径流损失）并提升作物生产力（包括氮素利用效率、氮素吸收量与作物产量），实现"双赢"效果。本研究通过量化平均效应并突破定性信息的局限，明确了能够助力全球应对活性氮危机、同时最大限度减少权衡取舍的"双赢"管理措施清单。
<b>关键词</b>：活性氮（Reactive Nitrogen）；二阶元分析（Second-order meta-analysis）；氮素减排；作物生产力；可持续农业

搜集汇总

背景与挑战

背景概述

该数据集通过二阶元分析评估了14种管理措施对全球活性氮危机的影响，基于6382项独特原始研究，旨在识别能同时减少氮损失和提高作物生产力的“双赢”实践。数据集包含多个数据文件，支持对氮减排和农业可持续性的量化分析，关键词包括活性氮、可持续农业等。