The effect of logging on atmospheric carbon concentrations remains highly contested, especially in the tropics where it is associated to forest degradation. To contribute to this discussion, we estimated the carbon balance from logging natural tropical forests in Costa Rica through a life cycle accounting approach. Our system included all major life cycle processes at a regional level during one rotation period (15 years). We used mass flow analysis to trace biogenic carbon. Data were gathered from all logging operations in the Costa Rican NW region (107 management plants), a sample of industries transforming wood into final products (20 sawmills), and national reports. We estimated a surplus of −3.06 Mg C ha⁻¹ 15 year⁻¹ stored within the system. When accounting for uncertainty and variability in a Monte Carlo analysis, the average balance shifted to −2.19 Mg C ha⁻¹ 15 year⁻¹ with a 95% CI of −5.26 to 1.86. This confidence interval reveals probabilities of a net increase in atmospheric carbon due to harvesting although these are smaller than those from a system that acts as a reservoir. Our results provide evidence for the carbon neutrality of bio‐materials obtained from natural forests. We found that anthropogenic reservoirs play a determinant role in delaying carbon emissions and that these may explain differences with previous carbon balance studies on tropical forest management. Therefore, the climate mitigation potential of forest‐derived products is not exclusive to forest management, but measures should be considered throughout the processes of wood transformation, use, and disposal.

中文翻译：

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哥斯达黎加热带森林中选择性伐木的生命周期碳平衡

伐木对大气碳浓度的影响仍然存在争议，特别是在热带地区，这与森林退化有关。为了促进讨论，​​我们通过生命周期核算方法估算了哥斯达黎加天然热带森林伐木的碳平衡。我们的系统包括一个轮换周期（15年）内区域级别的所有主要生命周期过程。我们使用质量流量分析来追踪生物碳。数据来自哥斯达黎加西北地区的所有伐木作业（107家管理厂），将木材转变为最终产品的行业样本（20个锯木厂）以及国家报告。我们估计有-3.06 Mg C ha ^-1 15年^-1的过剩存储在系统中。当在蒙特卡洛分析中考虑不确定性和可变性时，平均余额变为-2.19 Mg C ha ^-1 15年^-195％CI为-5.26至1.86。该置信区间显示了由于采伐而导致大气中碳净增加的可能性，尽管这些概率小于来自充当储层的系统的碳。我们的结果为从天然林获得的生物材料的碳中和提供了证据。我们发现，人为的储层在延迟碳排放中起决定性作用，这可能解释了与先前有关热带森林管理的碳平衡研究的差异。因此，森林产品的减缓气候变化的潜力并不仅仅局限于森林经营，而是应在木材转化，使用和处置的整个过程中考虑采取措施。