文章基本信息

标题：Large-scale expansion of agriculture in Amazonia may be a no-win scenario
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作者：Leydimere J C Oliveira ; Marcos H Costa ; Britaldo S Soares-Filho 等
期刊名称：Environmental Research Letters
印刷版ISSN：1748-9326
电子版ISSN：1748-9326
出版年度：2013
卷号：8
期号：2
页码：024021
DOI：10.1088/1748-9326/8/2/024021
语种：English
出版社：IOP Publishing Ltd
摘要：Using simplified climate and land-use models, we evaluated primary forests' carbon storage and soybean and pasture productivity in the Brazilian Legal Amazon under several scenarios of deforestation and increased CO₂. The four scenarios for the year 2050 that we analyzed consider (1) radiative effects of increased CO₂, (2) radiative and physiological effects of increased CO₂, (3) effects of land-use changes on the regional climate and (4) radiative and physiological effects of increased CO₂ plus land-use climate feedbacks. Under current conditions, means for aboveground forest live biomass (AGB), soybean yield and pasture yield are 179 Mg-C ha⁻¹, 2.7 Mg-grains ha⁻¹ and 16.2 Mg-dry mass ha⁻¹ yr⁻¹, respectively. Our results indicate that expansion of agriculture in Amazonia may be a no-win scenario: in addition to reductions in carbon storage due to deforestation, total agriculture output may either increase much less than proportionally to the potential expansion in agricultural area, or even decrease, as a consequence of climate feedbacks from changes in land use. These climate feedbacks, usually ignored in previous studies, impose a reduction in precipitation that would lead agriculture expansion in Amazonia to become self-defeating: the more agriculture expands, the less productive it becomes.