Harvested Wood Products as a Carbon Sink in China, 1900–2016

Abstract

The use of harvested wood products (HWPs) influences the carbon flux. China is both the major producer and trader of HWP, so estimating the carbon stock change of China’s HWP is important to help curb climate change. Accurate reporting and accounting of carbon flows in the HWP pool is needed to meet greenhouse gas monitoring and climate change mitigation objectives under the United Nations Framework Convention on Climate Change (UNFCCC) and the Paris Agreement. This study applied production approach (PA) to estimate the carbon stock change of China’s HWP from 1900 to 2016. During the estimating period, the carbon stock of HWP in use and deposed at solid waste disposal sites (SWDS) were 649.2 Teragrams Carbon (TgC) (346.8 TgC in wood-based panels, 216.7 TgC in sawnwood and 85.7 TgC in paper & paperboard) and 72.6 TgC, respectively. The carbon amount of annual domestic harvest HWP varied between 87.6 and 118.7 TgC. However, the imported carbon inflow increased significantly after the 1990s and reached 47.6 TgC in 2016, accounting for 46% of the domestic harvest of that year. China has great mitigation potential from HWP and use of this resource should be considered in future strategies to address climate change.

The lifecycle of wood from tropical forests in Costa Rica

“…In Costa Rica, wood is retired fast from the stock of products in use making SWDS responsible for most of the HWP contribution (77%), but their exclusion from national inventories (IPCC, 2014) will largely underestimate the country's stored carbon. This result is consistent with those found in similar studies (Ingerson, 2011;Skog et al, 2004;L. Zhang et al, 2019).…”

“…Re-utilization and recycling are still not common practices, as well as incineration of waste with or without energy recovery. In tropical countries the open burning of waste is common (Wiedinmyer, Yokelson, & Gullett, 2014;Yadav & Samadder, 2018;Ziegler-Rodriguez et al, 2019), but the information on the scale of open burning and EoL processes in general is extremely uncertain (Akagi et al, 2011;Bogner et al, 2008;Clavreul, Guyonnet, & Christensen, 2012;Pingoud & Wagner, 2006;L. Zhang, Sun, Song, & Xu, 2019).…”

“…This carbon stock is sometimes ignored when accounting for technospheric carbon storage because of the large uncertainties on waste flows towards EoL management, and because the decomposition of organic materials under anaerobic conditions may result in the release of methane, a more potent greenhouse gas (IPCC, 2014;Pingoud & Wagner, 2006). However, when carbon stored in SWDS is included, it may be significantly higher than the amount of carbon in products that are in use and given that only a small fraction of wood decomposes, methane emissions are usually not large enough to offset storage (Ingerson, 2011;Levasseur, Lesage, Margni, & Samson, 2013;Lun et al, 2012;Skog, Pingoud, & Smith, 2004;L. Zhang et al, 2019).…”

“…Prior to 1990, it was assumed that all wood products were disposed of in open dumps, where the half-life of wood products was 16.5 years (L. Zhang et al, 2019). After 1990, wood was sent to landfills and its half-life increased to 20 years (Pipatti et al, 2006) (Table 3.1).…”

“…Sawn wood production has increased globally but wood based panels showed an exponential growth and is now the most important wood product (Johnston & Radeloff, 2019). In China, the use of wood based panels is currently 20 times higher than in the 1990s and the carbon stock from sawn wood became a carbon source during 2000-2003(L. Zhang et al, 2019. Evidence of less wood used in construction is common in many parts of the world (Oliver & Mesznik, 2006) and the expected global growth in wood production appears to be driven by a growing demand for bioenergy (Akagi et al, 2011;Birdsey & Pan, 2015;Oliver & Mesznik, 2006;Pilli et al, 2015;Poker & MacDicken, 2016).…”