概括
现代农业严重依赖化石燃料,使作物生产易受能源成本上升的影响. 这种依赖性引发了人们对美国农业技术的可负担性和可持续性的担忧,因为发展中国家面临能源危机.
科学领域:
- 农业科学 农业科学
- 能源经济学 能源经济学
- 环境可持续性 环境可持续性
背景情况:
- 现代美国农业从根本上依赖化石燃料作为其主要投入.
- 目前的农业实践,特别是绿色革命技术,是能源密集型的,特别是关于肥料和农药.
- 美国在全球范围内分享其农业技术,但资源限制可能会挑战其广泛采用.
研究的目的:
- 评估高能耗农业实践的经济可行性和资源影响.
- 评估化石燃料成本上升对全球粮食安全的潜在影响.
- 探索减少农业能源投入的替代策略.
主要方法:
- 美国农业的能源投入与作物产量的分析.
- 考察化石燃料成本与作物生产成本之间的关系.
- 审查与能源密集型农业相关的现有挑战和潜在的未来问题.
主要成果:
- 美国玉米产量的很大一部分 (每英80加汽油等价) 是能源密集型的.
- 燃料成本的上升可能会使当前的农业能源回报不经济 (例如,每1kcal燃料2.8kcal玉米).
- 在全球燃料短缺的情况下,发展中国家可能难以负担美国能源密集型农业技术.
结论:
- 能源需求高的绿色革命农业对全球粮食安全构成风险,尤其是在能源危机期间.
- 像作物轮换和绿色肥料这样的替代方案对于减少对能源密集型肥料和农药的依赖至关重要.
- 随着传统能源资源变得稀缺和昂贵,农业实践的重大转变和潜在的劳动投入增加将是必要的.
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