The Fletcher School, Tufts University, Medford, MA 02155;Energy Biosciences Institute, University of California, Berkeley, CA 94704;
International Institute for Applied Systems Analysis, 2361 Laxenburg, Austria;
Proc Natl Acad Sci U S A. 2014 May 20;111(20):7236-41. doi: 10.1073/pnas.1307163111. Epub 2014 Apr 28.
This study examines whether policies to encourage cattle ranching intensification in Brazil can abate global greenhouse gas (GHG) emissions by sparing land from deforestation. We use an economic model of global land use to investigate, from 2010 to 2030, the global agricultural outcomes, land use changes, and GHG abatement resulting from two potential Brazilian policies: a tax on cattle from conventional pasture and a subsidy for cattle from semi-intensive pasture. We find that under either policy, Brazil could achieve considerable sparing of forests and abatement of GHGs, in line with its national policy targets. The land spared, particularly under the tax, is far less than proportional to the productivity increased. However, the tax, despite prompting less adoption of semi-intensive ranching, delivers slightly more forest sparing and GHG abatement than the subsidy. This difference is explained by increased deforestation associated with increased beef consumption under the subsidy and reduced deforestation associated with reduced beef consumption under the tax. Complementary policies to directly limit deforestation could help limit these effects. GHG abatement from either the tax or subsidy appears inexpensive but, over time, the tax would become cheaper than the subsidy. A revenue-neutral combination of the policies could be an element of a sustainable development strategy for Brazil and other emerging economies seeking to balance agricultural development and forest protection.
本研究探讨了在巴西鼓励肉牛养殖集约化的政策是否可以通过避免土地砍伐来减少全球温室气体(GHG)排放。我们使用全球土地利用经济模型,从 2010 年到 2030 年,研究了两种可能的巴西政策的全球农业结果、土地利用变化和 GHG 减排效果:对传统牧场的牛征收税和对半集约牧场的牛进行补贴。我们发现,无论采取哪种政策,巴西都可以实现相当大的森林保护和 GHG 减排,符合其国家政策目标。与增加的生产力不成比例的是,被节省的土地,特别是在税收的情况下,远低于预期。然而,尽管税收促使半集约化牧场的采用减少,但与补贴相比,它可以实现更多的森林保护和 GHG 减排。这种差异是由于补贴下牛肉消费增加导致的森林砍伐增加和税收下牛肉消费减少导致的森林砍伐减少所解释的。直接限制森林砍伐的补充政策可以帮助限制这些影响。税收或补贴带来的 GHG 减排似乎成本低廉,但随着时间的推移,税收将比补贴更便宜。这些政策的收入中性组合可能是巴西和其他寻求平衡农业发展和森林保护的新兴经济体可持续发展战略的一个组成部分。