Why Restoring Healthy Soils is Key to Tackling Climate Change

By: Polina Vinikhina

Superisor: Dr. Gesa Lüdecke

Soil is life.
Soil degradation due to climate change is a pressing issue that requires immediate action, which is why it is the topic of my final project. I decided to write a magazine article because I wanted to bring this issue to the attention of a large audience while also making it (hopefully) entertaining to read about. I think it is important that the general public understands the science behind climate change and the challenges the world will be facing as result given that they can influence the decisions of lawmakers while also reducing their individual carbon emissions.
The Earth beneath our feet is so ubiquitous it is usually taken for granted. Yet soil performs key functions that support ecosystem services beneficial to humans, such as water purification, rainfall regulation, flood prevention, nutrient cycling, and the reduction of contaminants. If we look beyond an anthropocentric perspective, it is clear that soil is also the foundation for all plant and animal life.
However, soil is finite. Currently, half of all habitable land globally is used as agricultural land, which leaves only 49% of habitable land to forests, shrubbery, and freshwater. There is clear tendency to clear wild habitats in order to make space for agricultural land. Today, approximately one-third of the world’s topsoil has been declared degraded. Unsustainable agricultural practices such as land clearing, over-tillage, excessive use of nitrogen fertilizers and pesticides, and the use of heavy machinery are the main contributors to land degradation. Given that it can take 500 to 1000 years for an inch of topsoil to develop, soil loss is occurring at a much faster rate than what can be naturally replenished. Climate change will further accelerate soil loss, impacting all of the creatures and microorganisms that rely on it.
The good news is that it is not too late to reverse this negative trend. Some strategies which have the potential to restore damaged soils to their natural healthy state are already being implemented around the world. Soil carbon sequestration is a popular strategy, which is often used to mitigate the effects of climate change. Increasing the amount of organic carbon in soil has the potential to reverse soil degradation, improving soil nutrient content and water-holding capacity, according to research.
Another viable strategy for decreasing soil loss is increasing vegetative cover. Land covered by plants is less prone to erosion since plants play an important role in dispersing wind and absorbing rainfall. Some projects around the world have successfully restored degraded land using the healing potential of plants. Regenerative agriculture is also being used as an approach to sustainable agriculture, which centers on developing soil health as a way of boosting soil productivity and increasing ecosystem resilience. Some preliminary research conducted in Latin America and Asia shows that increased soil health can lead to increased crop yields, but this method hasn’t been tested on a larger scale. However, even if this method proves successful in one part of the world, it is not guaranteed that the same beneficial results will be seen in another part of the world.
I also looked into the role of soil organisms in improving soil health, specifically earthworms and fungi. Earthworms, for instance, have been associated with multiple soil benefits. Through their borrowing activity, they produce aggregates and pores in the soil, which affect plant growth. Earthworm urine and mucus also supplies nutrients like N, P, K, and Ca to plants. Unfortunately, though, modern intensive farming methods are causing their communities to decline.
The role of fungi in ecosystem regulation has also been underestimated. Fungi modify the habitats of other organisms by participating in carbon and nutrient cycling, regulating diseases, assisting in decomposition, stabilizing soil carbon, and retaining moisture, thus influencing soil microbial community composition and the growth of other organisms. Fungi might also therefore be a part of the solution to climate change by serving as a necessary buffer for plants, assisting them to adapt to changing conditions and better tolerating stress.

With a third of the world’s land already degraded, we need to urgently start reversing soil degradation. None of the approaches to restoring soil health mentioned in this article should be considered a panacea. Such a complex problem like soil degradation requires a comprehensive solution. A shift from current intensive agricultural practices is inevitable if we want to ensure long-term soil health, with healthy soils being the foundation of healthy ecosystems. Once brought back to a healthy state, soils can continue to regulate ecosystems, enabling the harmonious coexistence of humans and other lifeforms.