Abstract. Estimates of the annual emissions of carbon from land use, land-use change, and forestry (LULUCF) are important for constructing global, regional, and national carbon budgets, which in turn help predict future rates of climate change and define potential strategies for mitigation. Here, we update a long-term (1850–2020) series of annual national carbon emissions resulting from LULUCF (https://doi.org/10.7910/DVN/U7GHRH, Houghton and Castanho, 2023), based largely, after 1960, on statistics of land use from the Food and Agriculture Organization (FAO) of the United Nations (http://www.fao.org/faostat/en/#data/, FAO, 2021). Those data suggest that rates of deforestation in the tropics (and thus net emissions of carbon) have decreased over the last 10 years (2011–2020). The data also indicate that the net loss of tropical forest area was greater than the net gain in agricultural lands, and we explore four alternative explanations for this apparent forest conversion, one of which is shifting cultivation. We also discuss how opposing trends in recent estimates of tropical deforestation (and emissions) might be reconciled. The calculated emissions of carbon attributable to LULUCF approximate the anthropogenic component of terrestrial carbon emissions, but limiting national carbon accounting to the anthropogenic component may also limit the potential for managing carbon on land.

中文翻译：

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1850 年至 2020 年土地利用、土地利用变化和林业每年产生的碳排放量

摘要。估算土地利用、土地利用变化和林业 (LULUCF) 产生的年碳排放量对于构建全球、区域和国家碳预算非常重要，这反过来有助于预测未来的气候变化速度并确定潜在的缓解策略. 在这里，我们更新了 LULUCF 导致的长期（1850-2020）年度国家碳排放量系列（https://doi.org/10.7910/DVN/U7GHRH，Houghton 和 Castanho，2023），主要基于 1960 年之后，联合国粮食及农业组织 (FAO) 的土地使用统计数据（http://www.fao.org/faostat/en/#data/，粮农组织，2021 年）。这些数据表明，热带地区的森林砍伐率（以及碳净排放量）在过去 10 年（2011-2020 年）有所下降。数据还表明，热带森林面积的净损失大于农业用地的净增加，我们探索了这种明显的森林转变的四种替代解释，其中之一是轮垦。我们还讨论了如何调和最近对热带森林砍伐（和排放）的估计的相反趋势。计算得出的归因于 LULUCF 的碳排放量近似于陆地碳排放的人为成分，但将国家碳核算限制在人为成分也可能限制管理土地碳的潜力。我们还讨论了如何调和最近对热带森林砍伐（和排放）的估计的相反趋势。计算得出的归因于 LULUCF 的碳排放量近似于陆地碳排放的人为成分，但将国家碳核算限制在人为成分也可能限制管理土地碳的潜力。我们还讨论了如何调和最近对热带森林砍伐（和排放）的估计的相反趋势。计算得出的归因于 LULUCF 的碳排放量近似于陆地碳排放的人为成分，但将国家碳核算限制在人为成分也可能限制管理土地碳的潜力。