The imprint of crop choice on global nutrient needs
The imprint of crop choice on global nutrient needs
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作物选择对全球养分需求的影响
DOI：
10.1088/1748-9326/9/8/084014
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发表时间：
2014
影响因子：
6.7
通讯作者：
O. Sala
中科院分区：
文献类型：
--
作者：
E. Jobbágy;O. Sala
在适宜土地有限和环境退化的世界中，满足日益增长的粮食需求的解决方案主要侧重于提高作物产量，特别是在表现不佳的地区，并减少动物产品消费。增加产量可以减轻对土地的需求，但会增加土壤养分的吸收，在大多数情况下会增加肥料的投入。降低动物产品消费有利于更有效地利用土地以及土壤和肥料养分;但实际节省可能在很大程度上取决于哪些作物和多少肥料用于喂养牲畜而不是人。通过全球分析，我们展示了用于喂养人类和牲畜的种植植物物种的选择如何影响全球粮食生产以及土壤养分吸收和肥料添加。我们在主要作物中报告的每单位能量或蛋白质产生的土壤养分提取量的3至15倍差异解释了过去20年来成分变化如何减少N，保持P和增加K从土壤中的收获提取，同时有助于增加膳食能量，蛋白质，特别是植物脂肪产量。由于作物之间差异很大，全球施肥率与实际土壤养分提取无关，但与收获产品的货币价值有关。未来作物组成的变化可能有助于实现更可持续的粮食系统，优化土地和肥料的使用。
Solutions to meet growing food requirements in a world of limited suitable land and degrading environment focus mainly on increasing crop yields, particularly in poorly performing regions, and reducing animal product consumption. Increasing yields could alleviate land requirements, but imposing higher soil nutrient withdrawals and in most cases larger fertilizer inputs. Lowering animal product consumption favors a more efficient use of land as well as soil and fertilizer nutrients; yet actual saving may largely depend on which crops and how much fertilizer are used to feed livestock versus people. We show, with a global analysis, how the choice of cultivated plant species used to feed people and livestock influences global food production as well as soil nutrient withdrawals and fertilizer additions. The 3 to 15-fold differences in soil nutrient withdrawals per unit of energy or protein produced that we report across major crops explain how composition shifts over the last 20 years have reduced N, maintained P and increased K harvest withdrawals from soils while contributing to increasing dietary energy, protein and, particularly, vegetable fat outputs. Being highly variable across crops, global fertilization rates do not relate to actual soil nutrient withdrawals, but to monetary values of harvested products. Future changes in crop composition could contribute to achieve more sustainable food systems, optimizing land and fertilizer use.