Want negative carbon emissions? Keep older, diverse forests around

Growing and preserving forests is a more effective use of land for producing negative carbon emissions than Biomass Energy with Carbon Capture and Storage (BECCS), according to a paper in Nature Communications. BECCS combines using plant matter to generate energy with sequestering the carbon generated in the process underground. Here’s CarbonBrief’s take on the paper.

Not only are forests a better way to go, a paper in Environmental Research Letters shows that BECCS has to be done right to be effective. From the paper:

Poor governance of the sustainability of bioenergy crop production can significantly limit the amount of CO2 removed by BECCS, through soil carbon loss from direct and indirect land use change. Only one-third of the bioenergy crops are grown in regions associated with more developed governance frameworks.

Growing forests also has to be done right. A paper in Proceedings of the Royal Society B about forests in southeast China shows that higher species diversity and higher age make for more carbon sequestration. Here’s CarbonBrief’s take on the paper. In short, keeping diverse, old-growth forests intact should be at the top of the list for carbon sequestration. And when restoring forests and growing new forests, go with multiple species over monoculture.

When planning for preserving, restoring or creating new forests, keep this bit of advice in mind from an article in Nature Climate Change:

…analysing the co-benefits of reforestation creates a much stronger case for action, as
decision-makers can see a broader range of societal and economic benefits. As Maginnis puts it, “you’ve got to be delivering other benefits. There’s got to be something else: land productivity, crop productivity, a reduction in siltation, or enhanced water availability.”