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国家粮食生产因作物多样性而稳定
Delphine Renard1,2, David Tilman3,4
1Bren School of Environmental Science and Management, University of California Santa Barbara, Santa Barbara, CA, USA. delphinerenard@hotmail.fr.
Nature
|June 21, 2019
概括
通过减少收获损失, 提高国内作物多样性提高了粮食系统的稳定性. 这一发现表明增加作物品种是确保稳定粮食供应的关键策略.
科学领域:
- 农业科学
- 生态学
- 粮食安全
背景情况:
- 全球粮食系统因需求增加,粮食储量减少和气候变化而面临不稳定.
- 现有的解决方案集中在提高产量,灌和耐干旱方面.
- 农作物多样性对国家收获稳定性的作用仍未得到充分研究.
研究的目的:
- 调查国家作物多样性的增加是否提高了国家总收获的年比年稳定性.
- 使用广泛的历史数据测试作物多样性稳定性假设.
主要方法:
- 分析了91个国家的176种作物的年产数据.
- 统计建模以评估有效的作物多样性与收获稳定性之间的关联.
- 控制灌,施肥,降水和温度等变量.
主要成果:
- 国家一级较高的实际作物多样性与国家总收获的时间稳定性相显著相关.
- 农作物多样性的稳定效应与降水变化的破坏效应相当.
- 增加多样性导致收获损失较低的年份的频率较低.
结论:
- 国家作物多样性是提高粮食系统稳定的关键因素.
- 增加国家作物多样性是确保稳定粮食供应的现有政策的补充策略.
- 这些发现支持了生态和农业系统的多样性与稳定性之间的理论联系.
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