In our last newsletter, we discussed how too much land is devoted to animal agriculture and not enough to carbon-absorbing forests. Reforestation is key to fighting the climate crisis. Numerous scientific studies conclude that trees can play a major role in removing CO2 from the atmosphere and slowing down global heating. But the best way to restore global forest cover is up for debate. All trees are not created equal, nor are the benefits of different reforestation methods or where we focus replanting programs. And what we eat affects the conversion of farm land to forest carbon sinks.
Research by Swiss scientists, published in the journal Science, says that reforestation can be the biggest and least expensive way to remove CO2 from the atmosphere. The study says that 11% of the total global land mass could support reforestation. That is 1.7 billion hectares, about the size of the US and China combined. And this is far more feasible than technology solutions that cannot operate at the vast scale required to sequester enough CO2 to slow down global heating.
Ethiopians planted 200 million trees in one day last July — a world record — and Canada has pledged to plant two billion trees by 2030. These are just some of the hugely ambitious re-greening programs but policy makers need to focus on which ones will be most effective.
So, what type of forests do we need? According to a study by British scientists published in the journal Nature, (see Reforest) the restoration of natural forests that contain many different species of trees is 40 times more effective as a carbon sink than monoculture plantations of conifers. These monoculture forests, those with a single type of tree, are more vulnerable to disease and if harvested for timber or pulp every 10-20 years will not store carbon for as long as natural forests that act as carbon sinks for decades.
The study also shows that tropical rainforest restoration is the most effective carbon sink because trees grow faster in the tropics, replanting is much less expensive, land values are much cheaper and there are more local tree species. And reforesting peat bogs in colder climates is counter-productive because they are effective carbon sinks on their own.
Another key question is how do we restore forests? Natural regeneration is the least expensive but takes longer. Reforestation schemes range from local community plant-by-hand programs to commercial tree planting and hi-tech drones specially designed to plant trees in difficult to reach terrain.
Photo: Dendra Systems
A British company, Dendra Systems, uses data analytics to map out planting areas and specially designed drones that can plant 120 fertilized seed pods per minute. The machines use air pressure to fire the seed pods into the soil that will start to grow when activated by water. The company estimates that this method is 150 times faster and 10 times cheaper than planting by hand and that 400 teams of drone operators can plant 10 billion trees a year. (See Drones).
So how do we create the incentives to roll out a new green carpet of forest cover? Trees will follow the money. We need comprehensive transition plans that make economic sense. Replacing annual cash crops or livestock revenue with payments to sequester carbon over decades requires careful design and implementation to deliver the desired effect. And timber companies need to be financially motivated to plant slower growing trees that store more carbon for longer. To be successful, reforestation plans must make economic sense for local people. For example, agro-forestry, which combines tree cover with growing crops such as coffee or corn, serves a dual purpose of restoring tree cover, helping crops grow in drought-stricken regions and generating income for farmers in Africa and Latin America.
The prestigious research group Food and Land Use Coalition, says there are at least $700 billion and possibly up to $1 trillion in global subsidies from governments to farmers and food companies. Almost all support the status quo – a broken food system which drives deforestation. Re-directing these incentives to encourage both reforestation and the production of plant-based foods which have a lower carbon footprint, is key to drawing enough CO2 out of the atmosphere to slow down global heating. Policy makers must take the lead. If they do, industry, farmers and foresters will follow.