Global demand for timber supplies is expected to surge by four times of today’s levels by the middle of this century. There are so many environmental benefits to using timber over building materials such as steel or concrete: it’s a sustainable resource with a much lower carbon footprint, and well-managed forests absorb carbon and support biodiversity.
However, while initiatives to boost the use of timber in construction are welcome, it does raise certain concerns and questions about whether timber can be sustainably managed to meet the growing demand in the future. Here’s an overview of some of the issues.
The effect of climate change on land use
One of the biggest current concerns is the warming climate. The effects of this can already be observed, from extreme weather events becoming more frequent to exotic species migrating to cooler northern regions. Here in the UK, there is an increase in the amount of invasive plant and insect species that are a threat to native wildlife.
Researchers at the University of Cambridge have highlighted the issue of changing agricultural land use, and what this means for timber production. A warmer climate means that land in the southern hemisphere is increasingly un-viable for agriculture as conditions are too hot and dry, pushing crop production further into the northern hemisphere.
A study by the Cambridge research team found that by 2100, the majority of the land in the northern hemisphere will be taken up for growing crops. This will displace forestry that currently occupies significant amounts of land in countries such as Canada, the USA, Russia, and China.
The threat to global forestry
This could translate into the loss of tens of millions of hectares of forests, and thus seriously deplete sustainable timber production. Ultimately if this situation is not managed carefully, it could lead to a deepening environmental emergency by the end of the century.
Dr Oscar Morton, a researcher in the University of Cambridge’s Department of Plant Sciences who co-led the study, explained: “There’s only a finite area of suitable land on the planet where we can produce food and wood – two critical resources for society.”
He added: “As climate change worsens and agriculture is forced to expand northwards, there’s going to be increasing pressure on timber production.”
Avoiding a conflict between crops and timber production
The scientists highlight the need to start planning now to avoid a clash between land use for food crops and land for timber production. The researchers project that global demand for food will double in the next 30 years as affluence increases in developing nations, and the population continues to grow.
Timber production is already under pressure from climate change, which is causing more frequent and devastating wildfires, such as those that devastated 33,048 hectares of land in Jasper National Park, Alberta, Canada, this summer. The fires not only destroyed forest land, but also wildlife, communities, and local economies.
Planning for a sustainable future
Sustainable forest management requires long-term planning, because unlike crops, trees take far longer to reach maturity. Softwoods such as pine, fir, spruce and larch take about 40 years to grow to a point where they are ready to harvest, and hardwoods such as oak, ash, and beech can take up to 150 years.
Dr Chris Bousfield, a postdoctoral researcher in the University of Cambridge’s Department of Plant Sciences and co-leader of the study, said: “We’ve got to be thinking 50 years ahead because if we want timber in the future, we need to be planting it now.”
He added: “The trees that will be logged by the end of this century are already in the ground – they’re on much slower cycles than food crops.”
David Edwards, Professor of Plant Ecology in the University of Cambridge’s Department of Plant Sciences and senior author of the study, said: “A major environmental risk of increasing competition for land between farming and forestry is that wood production moves into remaining areas of primary forest within the tropics or boreal zones.”
“These are the epicentres of remaining global wilderness and untouched tropical forests are the most biodiverse places on Earth. Preventing further expansion is critical.”
Dr Bousfield added: “Climate change is already causing challenges for timber production. Now on top of that, there will be this increased pressure from agriculture, creating a perfect storm of problems.”
All of the researchers highlighted the importance of not prioritising food supplies over timber supplies, which could be the path that the world is on course for if preventative action is not taken now. Timber supplies will become increasingly vital to survival as the complexities and challenges of climate change continue to grow.
Sustainable timber in the UK
The previous government committed to boosting timber production in the UK last year, and it is hoped that the present government will continue to follow this plan. However, researchers at the University of Bristol have found that the domestic timber supply is declining, and this will limit availability just as demand for timber is growing.
The researchers call for a more diverse approach to forest design, moving away from conifer monocultures and to a greater variety of tree species.
Matthew Leeder, from Bristol’s Faculty of Engineering, is leading the research. He said: “This approach is particularly timely given the global climate and biodiversity emergency, with experts warning of a potential catastrophic forest ecosystem collapse in the UK within the next 50 years.”
“The study lays the groundwork for a more regenerative use of timber in the UK, supporting a sustainable supply of domestic timber while promoting the regeneration of UK woodlands.”
The researchers aim to expand the study to understand more about optimum forestry ecology and how this can be balanced with sustainable timber extraction.