CO2 storage in trees – how does it work?

CO2 storage in trees – how does it work?

CO2 storage trees – How does it work?

We all know how important trees and plants are for producing oxygen and absorbing CO2. Especially lately there has been a lot of news about the climate crisis, global warming, sea level rise, CO2 offsetting and the importance of preserving trees, plants and forests. In this blog you can read some background information on how trees store our CO2 emissions.

How do trees absorb carbon and nitrogen?


CO2 (carbon dioxide) is one of the most important greenhouse gases. Deciduous trees are best suited for absorbing carbon, nitrogen and also ozone. The gases are absorbed through stomata in the leaf. Through photosynthesis, the plant or tree transforms these gases into oxygen and plant material. The wider the leaf surface, the more effective trees are at this. Remarkably, the Amazon rainforest alone is responsible for 40% of all oxygen on Earth. And this while it covers only 6% of the entire earth’s surface. This does show the importance of preserving and protecting the rainforest.

On average, a tree removes between ten and forty kilos of CO2 from the air per year. A thirty year old tree has extracted and sequestered about a ton of CO2 from the air. The CO2 remains stored in the wood and roots as long as the tree lives. They need this CO2 to grow, for leaves, needles, flowers and fruit. About half of the tree’s dry weight is carbon; the rest is hydrogen, oxygen, nitrogen and minerals.

Simply by what they are and do, forests thus moderate the temperature on planet Earth. The imminent excess of CO2 in the atmosphere can therefore be reduced by promoting the growth of trees and preserving existing trees, so that as much carbon as possible can be sequestered in forests. In this way, trees ensure that we can live on this planet.

Capturing more carbon can be done by:
– increasing the wood stock in the existing forest, i.e. “saving” wood and not cutting it;
– promoting diversity and growth in the existing forest, for example enriching coniferous forests with the planting or stimulation of deciduous trees;
– planting new forest on land that is not currently forested, such as pasture, heath or fields.


Mangroves have the ability to store large amounts of carbon dioxide – up to four times as much carbon as other tropical forests. A 2018 study calculated that the world’s mangrove forests soak up more than 6 billion tons of carbon per year. This clearly makes them a really important player in the fight against climate change. The problem is that they are threatened worldwide.

I spoke to several Costa Ricans, also known as Ticos, and all those I spoke to saw with pain in their hearts that mangrove forests are slowly disappearing. Because of sea level rise, more salt water is entering the mangroves and there is less brackish water. Mangroves need this brackish water to thrive. So sea level rise has a direct effect on mangrove forests, and thus direct impact on CO2 storage.

Several reasons to protect mangrove forests: they store CO2 and can hold it for many thousands of years. In addition, mangrove forests serve as protection for the rainforest located further inland; they provide a buffer, so to speak, between the salty sea water and the fresh inland water. When mangroves disappear due to sea level rise, the adjacent rainforest is also indirectly at risk.

The decomposition of wood releases CO2 and requires oxygen

During the life of trees, decomposition of organic matter also takes place. Leaves fall every year. The lower branches of trees also die sooner or later due to lack of light. In addition, trees produce fruits and seeds, which also fall to the ground. All this material slowly decays on the forest floor: it is reduced and broken down by insects, fungi and bacteria. In this decomposition, the opposite happens as during the growth of trees: it releases CO2 and requires oxygen. Fortunately, in a healthy forest, more greenery always grows than dies.

However, due to human influence, large-scale deforestation takes place. This releases much more CO2 than natural processes when only a few (old) branches break off. That is why it is so important to preserve and protect the existing rainforest! And that is why it is so important to encourage the planting of new trees/forests.

The more trees, the more CO2 is absorbed and the more oxygen is produced.

Reducing your CO2 emissions

There are many ways to reduce your CO2 emissions. For example, by leaving your car at home more often and not going on a plane vacation this year. Turning up the heat less often also helps. And did you know that your belongings, such as clothing, also have a great impact on the environment? This is partly because a lot of CO2 emissions are released during the production of items and transportation. So if you buy less or second-hand, you automatically contribute to a better earth!

Furthermore, the positive impact of eating plant-based food (more often) is enormous. For the production of meat and animal feed, a lot of forest is cut down and water is consumed. Moreover, a lot of greenhouse gases are released in the process. For comparison: the production of one piece of beef releases 34 kilos of CO2. For a vegetarian burger this is only 2.6 kilos

Offsetting your CO2 emissions

If you still want to do more than just reduce your emissions, you could also offset your emissions. There are several initiatives where, by making a donation, you can have trees planted or adopt a piece of rainforest to offset your air or car travel.

How many trees should you plant or how much rainforest should you adopt to offset the CO2 emissions of a plane trip or car ride?

For example, to offset the CO2 emissions from a car trip of about 5,000 kilometers, you would need to plant about 20 trees per year. Or adopt 37 square meters of rainforest. For a flight of 10,000 kilometers, you would need to plant about 90 trees per person or adopt 100 square meters of rainforest to offset emissions.

Wondering how big your footprint is? Do the math on our website!