土地清理和生物燃料碳债务
Joseph Fargione1, Jason Hill, David Tilman
1The Nature Conservancy, 1101 West River Parkway, Suite 200, Minneapolis, MN 55415, USA.
概括
生物燃料可以是低碳的,但从土地转换中生产它们会产生大量的碳债务. 从废物或退化土地中可持续生产生物燃料提供了直接的温室气体优势.
科学领域:
- 环境科学 环境科学
- 气候变化研究 气候变化研究
- 可持续能源 可持续能源
背景情况:
- 能源需求的增加和气候变化迫使人们转向低碳燃料.
- 生物燃料是化石燃料的潜在替代品,但它们对环境的影响有所不同.
- 二氧化碳 (CO2) 排放是气候变化的主要驱动因素.
研究的目的:
- 评估与不同生物燃料生产方法相关的碳债务.
- 为了比较以作物为基础的粮食与以废物为基础的生物燃料对温室气体 (GHG) 的影响.
- 确定生物燃料提供真正碳节约的条件.
主要方法:
- 来自各种生物燃料原料的温室气体排放的生命周期评估.
- 从生物燃料生产的土地使用变化而产生的碳债的量化.
- 生物燃料的二氧化碳排放量与化石燃料的比较.
主要成果:
- 将自然生态系统 (雨林,泥炭地,草原,草原) 转化为生产粮食作物生物燃料,会产生相当大的"生物燃料碳债务".
- 这种碳债务是每年减少温室气体排放量的17至420倍,比取代化石燃料的温室气体排放量要大.
- 从废弃生物质中提取的生物燃料或在退化/废弃土地上种植的生物燃料显示碳负债很小或不存在.
结论:
- 生物质的来源对于确定生物燃料的气候效益至关重要.
- 来自土地转型的基于粮食作物的生物燃料不是可持续的低碳解决方案.
- 利用废弃物生物质或恢复退化土地用于生物燃料生产提供了显著和立即的温室气体优势.
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