In the battle against climate change, afforestation stands as a powerful ally, creating new carbon sinks and boosting wood supply. However, the impacts of climate change on tree growth and wood quality are complex and not always well understood. A recent study led by Isabelle Ménard, a researcher at the Research Centre on Renewable Materials, Department of Wood and Forest Sciences, Université Laval, and the Direction de la recherche forestière, ministère des Ressources naturelles et des Forêts, Québec, sheds new light on this intricate relationship.
Ménard and her team delved into the effects of climate change on wood quality and carbon storage in harvested wood products. Their focus was on plantations of black spruce on open woodlands and hybrid poplar on abandoned farmlands in Québec, Canada. Using a multi-model approach, they estimated carbon stocks under various climate change scenarios.
The findings reveal a nuanced picture. Increased climate forcing, or the additional energy trapped by greenhouse gases, negatively impacts the quality of the harvested wood product basket. This means that the type and quality of wood available for primary processing—such as lumber and pulpwood—will change. “The relative amount of lumber versus pulpwood is influenced by climate change,” Ménard explains, highlighting the need for adaptability in the wood processing industry.
However, the story doesn’t end with wood quality. The study also examined the end-of-life scenarios for these wood products. Surprisingly, the decay of solid wood products in landfills produced more methane emissions than paper. Methane, a potent greenhouse gas, poses a significant challenge to the climate change mitigation potential of wood products. “The decay of solid wood products in landfills produced more methane emissions than paper, which may constrain their climate change mitigation potential in the absence of methane capture or flaring,” Ménard notes.
But there’s a silver lining. The cascading use of solid wood products in bioenergy at the end of their service life significantly reduced overall emissions. This approach not only maximizes the use of wood but also minimizes waste and emissions. “This study highlights how comprehensive afforestation strategies can, in the long term, be used to maximize the carbon storage potential of harvested wood products sourced from new plantations,” Ménard says.
For the energy sector, these findings are a call to action. As we ramp up afforestation efforts, we must also invest in better use of pulp-quality wood, improved cascading use at the end-of-life of wood products, and, crucially, the avoidance of methane emissions from landfilled wood. This research, published in Trees, Forests and People, underscores the need for a holistic approach to afforestation and wood product management. It’s not just about planting trees; it’s about creating a sustainable, low-emission future for the energy sector.
As we look to the future, this research could shape developments in forestry management, wood processing, and bioenergy. It challenges us to think beyond the initial carbon sequestration benefits of afforestation and consider the entire lifecycle of wood products. By doing so, we can maximize their climate change mitigation potential and create a more sustainable energy landscape.
