What happens with stored CO2 when a tree dies?

Forests are carbon sinks. As trees decompose, they release some CO2, making room for new growth to absorb similar or greater amounts of CO2

Forests are living carbon sinks: natural environments capable of storing vast amounts of carbon dioxide (CO₂).

During the process of photosynthesis, trees absorb CO₂ and combine it with water to produce sugars for their sustenance, releasing oxygen into the atmosphere. Besides trees, forest soils are home to varied greenery that also serves to store CO₂.

When a tree dies, it releases some of its stored CO₂ back into the atmosphere. The amount and rate of this release depend on the quality and quantity of its material. For instance, wood decomposes slowly, gradually releasing CO₂ over time. In contrast, leaves and smaller organic matter can become part of the forest soil's carbon layer, continuing to be part of its carbon sink. A dead tree allows space and sunlight to foster new growth, enabling new trees to replace it and continue absorbing CO₂.

Reforestation helps restore degraded forests, while afforestation creates new ones, both maximizing the capacity of our forest carbon sinks. In terms of carbon capture, the natural death of a tree does not significantly impact a forest's overall ability to store CO₂, provided the whole forest is well-maintained and protected from deforestation.