A common idea is that substituting wood for fossil fuels and energy intensive materials is a better strategy in mitigating climate change than storing more carbon in forests. This opinion remains highly questionable for at least two reasons. Firstly, the carbon footprints of wood-products are underestimated as far as the “biomass carbon neutrality” assumption is involved in their determination, as it is often the case. When taking into account the forest carbon dynamics consecutive to wood harvest, and the limited lifetime of products, these carbon footprints are time-dependent and their presumed values under the carbon neutrality assumption are achieved only in steady-state conditions. Secondly, even if carbon footprints are correctly assessed, the benefit of substitutions is overestimated when all or parts of the wood products are supposed to replace non-wood products whatever the market conditions. Indeed, substitutions are effective only if an increase in wood product consumption implies verifiably a global reduction in non-wood productions. When these flaws in the evaluation of wood substitution effects are avoided, one must conclude that increased harvesting and wood utilization may be counter-productive for climate change mitigation objectives, especially when wood is used as a fuel.

一个普遍的想法是，用木材代替化石燃料和能源密集型材料比在森林中存储更多的碳是一种更好的缓解气候变化的策略。至少由于两个原因，这种观点仍然值得高度质疑。首先，就木炭产品的碳足迹而言，只要是“生物量碳中和”假设就被低估了，这是经常发生的情况。考虑到木材采伐后森林碳动态变化以及产品寿命有限，这些碳足迹与时间有关，并且仅在稳态条件下才能达到碳中和假设下的假定值。其次，即使正确评估了碳足迹，当无论市场条件如何，全部或部分木制品都将替代非木制品时，替代的好处被高估了。的确，只有在木材产品消费增加可证实全球非木材产量减少的情况下，替代才有效。如果避免了在评估木材替代效果方面的这些缺陷，就必须得出结论，增加采伐量和木材利用量可能对减缓气候变化目标产生反作用，尤其是当木材用作燃料时。