What is the best CO₂ sink: German mixed forest or monoculture?

Single-species (or monoculture) forests that have been severely damaged by pests such as the bark beetle in recent years have lost their ability to bind CO₂. However, forests in general remain an important CO₂ sink.

Climate-resistant mixed-species forests in particular offer enormous potential for long-term CO₂ sequestration. The conversion of monoculture forests to climate-stable mixed ones could decisively contribute to maintaining our forests as natural carbon absorbers, while also strengthening their resilience to the challenges of climate change.

Forests in Germany: CO₂ emitter or CO₂ sink?

The results of the 2022 National Forest Inventory made headlines, giving the impression that forests in Germany are increasingly emitting CO₂. However, this balance refers exclusively to the net value, which measures the difference between CO₂ sequestration and losses due to pests, drought and storms.

In fact, forests in Germany continue to bind large amounts of CO₂. However, this sequestration is not sufficient to achieve the ambitious climate target set by the German government for the agriculture and forestry sector. The negative trend in recent years is mainly due to the spread of monocultures, since these types of forest stands are heavily burdened by climatic changes and pests, which considerably limits their ability to store carbon.

Monocultures weaken the forest’s role as a CO₂ sink

Particularly in the case of monocultures, the net CO₂ balance looks less good because these types of forests have suffered considerably from pests and extreme weather conditions in recent years. Monoculture forests are less resilient to climatic changes and can no longer fulfill their function as CO₂ sinks. This is a direct consequence of intensive management and a lack of diversity in tree species.

The German forest as a CO₂ sink: why the forest itself is not the CO₂ emitter

It is important to emphasize that forests are not CO₂ emitters per se. Forests continue to play an indispensable role in climate protection. Mixed forests are particularly important in this respect. Even though many forest stands are suffering from the consequences of climate change, there are still numerous forests that bind CO₂. It is the conversion of more vulnerable monocultures into climate-resilient mixed forests that has the potential to turn forests back into stable CO₂ sinks. Through the targeted afforestation of climate-resilient mixed forests, the potential of the forest as a CO₂ sink can be effectively expanded in the long term.

Planting mixed forests strengthens the CO₂ storage function of the forest

Afforestation with climate-resilient mixed forests is crucial in order to preserve the German forest as a CO₂ sink in the long term. The targeted conversion of monocultures and the reforestation of damaged areas with a diverse mixture of deciduous and coniferous trees not only increase the resilience of the forest, but also its ability to bind CO₂. Only through structural diversity and near-natural management can the forest withstand the increasing stress caused by extreme weather, pests and drought. However, the 2022 Federal Forest Inventory makes it clear that the net CO₂ sequestration of German forests is not yet sufficient to achieve the targets of the Federal Climate Protection Act. The climate targets for the LULUCF sector state that 25 million tons of CO₂ are to be sequestered annually by 2030. Afforestation with mixed forests is therefore a key measure for meeting the climate targets.

Mixed forests are the key to a climate-stable forest

Mixed forests increase CO₂ sequestration and make German forests more adaptable to the consequences of climate change. Different tree species such as beech, oak, Douglas fir and birch complement each other in the ecosystem, which strengthens biodiversity and reduces the risk of large-scale failures due to pests or extreme weather conditions. Compared to monocultures, which suffer greatly from current climate conditions and release CO₂, mixed forests are a robust and sustainable solution. Their diversity makes them an effective CO₂ sink - today and in the future. The consistent conversion to climate-stable mixed forests is therefore a key to securing the forest in Germany as a natural ally in climate protection.

The forest remains our most important ally in climate protection

The recent National Forest Inventory results present the net carbon footprint of Germany’s forests as less effective than it really is. Despite the challenges, forests should not take a back seat as climate protectors. On the contrary. It is crucial that the conversion to climate-stable mixed forests be recognized as a long-term solution. Quick results are difficult to expect due to the slow growth of trees, especially outside of coniferous forest monocultures.

Nevertheless, the solutions of forest conversion and the afforestation of climate-resistant mixed forests must be pursued further. The potential of forests as a CO₂ sink is enormous. And at the same time a fundamental pillar for climate protection.

Forests have an amazing ability to recover and regenerate if they are given the right conditions. This requires decisive action and a legal framework to secure Germany’s forests as reliable CO₂ sinks.

A strong federal forest law could set the course for a more sustainable and climate-friendly forestry sector. Only with sustainable management and an increase in mixed forests can we exploit the full potential of forests in the fight against climate change.

The time to act is now - for the forest and for our climate. Mixed forests are the key to preserving our forests as CO₂ sinks and promoting biodiversity. If we manage and protect the forest properly, we can secure a future worth living for us all.