International Industrial Ecology Day 2021

Wood-based products can contribute to climate change mitigation by prolonging the carbon storage in the anthroposphere. In Indonesia, however, many wood-based products originate from unsustainable sources due to widespread land-use changes, indicating the need for a comprehensive carbon life cycle assessment (LCA), covering biospheric and technospheric woody carbon flows and emissions over time. Here, we combine dynamic material flow analysis, stock modeling, and LCA to estimate life cycle carbon emissions over time of wood products from different land conversion types in Indonesia on a hectare (ha) basis. Wood production from clear-cut primary forest conversions to oil palm, timber plantations, and secondary forest lead to net carbon emissions between 429-1290 t CO2-eq/ha at the end of the 200-year time horizon (TH). Counter-use scenarios of using non-renewable materials or energy instead of wood-based products, while leaving the primary forest untouched, display 5 – 88% lower global warming potentials at the end of the TH. Wood products from forest plantations on restored degraded land (DL_FP) and reduced-impact logging (RIL) of primary forest went beyond carbon neutrality, displaying carbon removal potentials of up to around -231 and -62 t CO2-eq/ha, respectively. At one ha-scale, our results indicate that keeping primary forests intact is the climate-preferable option, even when emissions from the counter-use of non-renewable materials or energy are factored in. The wood product utilization would only be favorable from a climate perspective in DL_FP or RIL pathways. The DL_FP, in particular, displays negative emission potentials that are lower than its counter-use scenario. As an outlook, we also spatially quantify degraded land area that can be potentially restored and utilized for wood production at a national scale, which amounted to 3.8 Mha. These results help screen different land conversion policy options and providing information about the climate mitigation potential of wood products in different supply chains.