What are Nature-based Solutions (NbS)?
Nature-based solutions (NbS) are important measures that can help reduce global warming and its effects on the environment and people. They exploit the natural ability of plants to convert carbon dioxide from the atmosphere into carbon by means of photosynthesis and to store it over the long term. Nature-based solutions are becoming increasingly important and are essential in the fight against climate change. There are basically two processes. Let’s take a closer look at them.
In order to limit global warming to 1.5°C, humankind must not only immediately emit less CO₂, but also remove CO₂ from the atmosphere at the same time. Examples of nature-based solutions for the avoidance of CO₂ emissions include the prevention of deforestation of existing forests and the rewetting of moors. For the removal of CO₂ from the atmosphere, there are some solutions in the field of nature-based climate protection processes that sequester CO₂ from the atmosphere. This is known as carbon dioxide removal (CDR). This includes afforestation, humus formation in agricultural soil and the planting of seagrass meadows in coastal regions – known as nature-based carbon dioxide removal or nature-based negative emissions.
In other words, there are not just technological options for limiting global warming and reducing the risk of catastrophe, such as the decarbonisation of the economy and society, or technological CO₂ removal or geochemical processes. There is also the natural option, specifically the conservation (avoidance) and rewilding (biological CO₂ removal) of the Earth’s ecosystems. Nature-based negative emissions are a type of CO₂ storage and are one aspect of NbS.
The protection and regeneration of ecosystems such as forests and moors should also increase nature’s resistance to climate change. The European Commission defines nature-based solutions as those “...that are cost-effective, simultaneously provide environmental, social and economic benefits, and help build resilience.” One important goal for climate protection is to avoid emissions resulting from the destruction of ecosystems and to strengthen their natural function. These habitats offer society a variety of other important ecosystem services, such as recreation, drinking water, protection of biodiversity and a source of sustainable raw materials such as timber. All measures focus on the protection of nature, as well as climate protection.
The global community has recognised the importance of healthy ecosystems. The UN Decade on Ecosystem Restoration started on 5 June 2021. With this programme, the United Nations aims to remove no less than 26 gigatonnes of greenhouse gases from the atmosphere between 2021 and 2030. Because ecosystems perform the opposite process to the burning of fossil energy sources: carbon dioxide is stored and oxygen is released.
Nature-based solutions can be implemented in both marine and terrestrial ecosystems. The protection of (mangrove) forests, moors or coral reefs leads to the avoidance of emissions and preserves the functionality of existing habitats. Reforestation, the restoration of ecosystems, the conversion of forests into climate-stable mixed tree stocks and the transition from industrial to regenerative farming practices are all measures that remove CO2 from the atmosphere in the long term, while making a valuable contribution to unspoiled, stable habitats (removal). Another thing all these nature-based solutions have in common is that the carbon enriched by photosynthesis and micro-bacterial processes remains in nature and is not released into the atmosphere. The sustainable use of forests also makes an active contribution to climate protection and reduces emissions, provided it can be guaranteed that no more timber is taken from the forest than will regrow, and that the raw timber is primarily used as a material, in the form of timber for construction or furniture.
Unlike purely technological solutions such as carbon capture and storage, nature-based solutions always make an important contribution to sustainable development. Soil farmed regeneratively is better for species diversity, provides healthier food and creates good working conditions. An unspoiled forest provides recreational space, creates fresh air and is a source of responsible and sustainable timber.
Nature-based solutions are as varied and universal as life itself. Below you will find information about some possible projects that promote climate protection and conservation and are classed as nature-based solutions. They can be seen in the illustration.
In coastal regions, seagrass meadows planted below sea level can store twice as much CO2 as many rainforests and provide an increasingly scarce habitat for fish and other marine fauna. The regeneration of coral reefs must be encouraged, not only to preserve one of the most important and most threatened marine ecosystems, but also to maintain the carbon-reducing function of the oceans.
Previously forested regions of the coast can be replanted with mangroves, as these types of trees can store particularly large volumes of CO2. The roots also provide a habitat for fish and protect the sandy shores from erosion. The rewetting of drained moors also makes an important contribution to climate protection. Drained peat emits methane, a greenhouse gas which is very harmful to the climate. This process is stopped by rewetting, whereby the greenhouse gas stays in the ground.
In forest ecosystems, carbon is stored through afforestation or the sustainable use of forests. Afforestation, reforestation, conversion of forests to climate-tolerant mixed tree stocks, as well as reduced management of forests or the creation of protected zones – these measures all result in healthy and stable trees able to fulfil their important function for people and nature, not just for us, but for future generations too. Flat roof and façade greening can also make a contribution.
There are also numerous possibilities to improve the carbon balance for the sake of climate protection in agriculture. Altered crop rotation, reduced fertiliser use, tree planting in fields in productive agroforestry systems, as well as the use of biochar to increase the carbon content of soil are all measures to bind and avoid carbon.