Pretty J N, Ball A S, Xiaoyun Li, Ravindranath N H
Centre for Environment & Society and Department of Biological Sciences, University of Essex, Wivenhoe Park, Colchester CO4 3SQ, UK.
Philos Trans A Math Phys Eng Sci. 2002 Aug 15;360(1797):1741-61. doi: 10.1098/rsta.2002.1029.
This paper contains an analysis of the technical options in agriculture for reducing greenhouse-gas emissions and increasing sinks, arising from three distinct mechanisms: (i) increasing carbon sinks in soil organic matter and above-ground biomass; (ii) avoiding carbon emissions from farms by reducing direct and indirect energy use; and (iii) increasing renewable-energy production from biomass that either substitutes for consumption of fossil fuels or replaces inefficient burning of fuelwood or crop residues, and so avoids carbon emissions, together with use of biogas digesters and improved cookstoves. We then review best-practice sustainable agriculture and renewable-resource-management projects and initiatives in China and India, and analyse the annual net sinks being created by these projects, and the potential market value of the carbon sequestered. We conclude with a summary of the policy and institutional conditions and reforms required for adoption of best sustainability practice in the agricultural sector to achieve the desired reductions in emissions and increases in sinks. A review of 40 sustainable agriculture and renewable-resource-management projects in China and India under the three mechanisms estimated a carbon mitigation potential of 64.8 MtC yr(-1) from 5.5 Mha. The potential income for carbon mitigation is $324 million at $5 per tonne of carbon. The potential exists to increase this by orders of magnitude, and so contribute significantly to greenhouse-gas abatement. Most agricultural mitigation options also provide several ancillary benefits. However, there are many technical, financial, policy, legal and institutional barriers to overcome.
本文分析了农业领域减少温室气体排放和增加碳汇的技术选择，这些选择源于三种不同机制：（i）增加土壤有机质和地上生物量中的碳汇；（ii）通过减少直接和间接能源使用避免农场碳排放；（iii）提高生物质可再生能源产量，这既可以替代化石燃料消费，也可以取代低效燃烧薪柴或作物残渣，从而避免碳排放，同时结合使用沼气池和改良炉灶。然后，我们回顾了中国和印度的最佳实践可持续农业及可再生资源管理项目和倡议，分析了这些项目创造的年度净碳汇以及所固碳的潜在市场价值。我们最后总结了农业部门采用最佳可持续性实践以实现预期减排和增加碳汇所需的政策和体制条件及改革。对中国和印度40个基于这三种机制的可持续农业及可再生资源管理项目的审查估计，550万公顷土地的碳减排潜力为每年6480万吨碳。按每吨碳5美元计算，碳减排的潜在收入为3.24亿美元。存在将这一数字提高几个数量级的潜力，从而为温室气体减排做出重大贡献。大多数农业减排选择还带来若干附带效益。然而，仍有许多技术、资金、政策、法律和体制障碍需要克服。
