Sequestration of CO2 – Burnt forests

In order to reduce CO2 emission, there are multiple things we can do right now, without reaching for geo-engineering techniques that could have unforeseen consequences.

One of these things is management of forest after wildfires.

Original photo source: "Eglin Air Force Base" 

Just this year (2017), wildfires have destroyed more than 4 million acres (1.6 million hectares) across Chile, Portugal, Canada, U.S., Russia, Australia, and many others.

Much of what has burned has been turned to ashes, but a good portion of branches and tree trunks have not been burned completely, being either turned to charcoal or untouched in the core.

In 2008, a 10-year study revealed that charcoal left on the surface shrunk by nearly 25%, losing a significant portion of its carbon within the first two years of the 10 year period—especially when covered with the litter of decomposing tree leaves.

Aside from crippling nature’s ability to sequester CO2, burning forests release huge amounts of CO2, and afterwards, as the above study revealed, they continue releasing CO2 under the influence of weather and microbes.

To reduce this after-emission and allow for faster recovery of areas affected by wildfires, burned forests could be managed in a certain way.

The simple idea is to prevent charcoal from emitting CO2 over time by forest management.

    That should include:
  • cutting burned trees;
  • collection of the charcoal or wooden debris;
  • tree root shredding (if possible, depending on terrain);
  • trunk and charcoal burying (in order to slow down decomposition, and reforestation should take place); and
  • immediate road panning and construction to prevent the spread of further wildfires and allow for easier collection of leaves or taking care of young trees.

Creating long-term carbon deposits by burying wood is based on Ning Zeng’s ‘Carbon sequestration via wood burial’ paper from 2008, and I have already mentioned it several times. If we would place those deposits beneath newly-built roads, those half-burned tree parts—if properly buried, kept dry, and away from microbes—could stay there for a very long time, without emitting significant amounts of CO2 into the atmosphere.

Now, the only thing left to do is a comparison between young forest recovery that is managed in this way and forests that have not been managed, leaving them to recover on their own. Although, that research would be quite handy; as we are running out of time, we should not wait but should apply existing knowledge and the wisdom we already have, doing the research on the go.

Comments