There is increasing attention on the importance of biodiversity for food security and nutrition, especially above-ground biodiversity such as plants and animals. However, less attention is being paid to the biodiversity beneath our feet, soil biodiversity, which drives many processes that produce food or purify soil and water. This summary for policy makers presents the key findings of the main report and is the result of an inclusive process involving more than 300 scientists from around the world under the auspices of the FAO’s Global Soil Partnership and its Intergovernmental Technical Panel on Soils, the Convention on Biological Diversity, the Global Soil Biodiversity Initiative and the European Commission. The summary for policy makers presents concisely the state of knowledge on soil biodiversity, the threats to it and the solutions that soil biodiversity can provide to problems in different fields. This report is a valuable contribution to raising awareness of the importance of soil biodiversity and highlighting its role in finding solutions to today's global threats.

Soil organisms play a crucial role in boosting food production, enhancing nutritious diets, preserving human health, remediating pollution and combating climate change, but their contribution remains largely underestimated, the Food and Agriculture Organization of the United Nations said today in its report on "The State of Knowledge of Soil Biodiversity". The report was launched on the occasion of World Soil Day, marked on 5 December.

Despite the fact that biodiversity loss is at the forefront of global concerns, the biodiversity that is below ground is not being given the importance it deserves and needs to be fully taken into account when planning interventions for sustainable development, the report says.

"Soils are not only the foundation of agri-food systems and where 95 percent of the foods we eat is produced, but their health and biodiversity are also central to our efforts to end hunger and achieve sustainable agri-food systems," said FAO Director-General QU Dongyu at the World Soil Day ceremony today.

However, the FAO chief pointed to the decline in soil health and numerous ecosystem services they provide. To avoid dramatic consequences this trend may have on food security, nutrition, climate change and sustainable development, he called for urgent actions to unlock the potential of living genetic resources in soils.

In his remarks, Qu also highlighted the need for establishing an efficient global soil information system in line with digital agriculture and innovations in environmetrics, to protect our "silent, dedicated heroes" as he referred to soil organisms.

"As a Chinese proverb says: Soil is the Mother of all creatures on earth. Do not forget the Mother when you are getting nourishment from," the Director-General said.

Soils are one of the main global reservoirs of biodiversity. They host more than 25 percent of the world's biological diversity. In addition, more than 40 percent of living organisms in terrestrial ecosystems are associated with soils during their life cycle.

Elizabeth Maruma Mrema, Executive Secretary of Convention on Biological Biodiversity, in her video address to the ceremony, said: "We urgently need to recognize that soil biodiversity is indispensable to food security and the achievement of the Sustainable Development Goals. Soil biodiversity underpins the productivity and resilience of agriculture, making production systems and livelihoods more resilient to shocks and stresses."
The new FAO report defines soil biodiversity as the variety of life below-ground, from genes and species to the communities they form, as well as the ecological complexes to which they contribute and to which they belong, from soil micro-habitats to landscapes.

The role of soil biodiversity through the ecosystem services they provide is critical for agriculture and food security.

For example, soil microorganisms transform organic and inorganic compounds releasing nutrients in a form that plants can feed on. In addition, soils diversity contributes to improving the control, prevention, or suppression of pests and pathogens.

However, soil biodiversity is threatened by human activities, climate change and natural disasters. The overuse and misuse of agrochemicals remains one of the major causes of soil biodiversity loss, thus reducing the potential of soil biodiversity. Other causes include deforestation, urbanization, agricultural intensification, pollution, and salinization.

Soil biodiversity and human well-being

Soil microorganisms have a significant potential to mitigate climate change. They play a key role in carbon sequestration and reducing greenhouse gas emissions. The report finds that farming activities are the biggest source of carbon dioxide and nitrous oxide gases emitted by soils.

Soil biodiversity supports human health, both directly and indirectly. Several soil bacteria and fungi are traditionally used in the production of soy sauce, cheese, wine, and other fermented food and beverages. Plants produce chemicals such as antioxidants that stimulate our immune system and contribute to hormone regulation. Soil microorganisms can also help prevent chronic inflammatory diseases, including allergy, asthma, autoimmune diseases, inflammatory bowel disease, and depression.

Since the early 1900s, many drugs and vaccines have been derived from soil organisms, from well-known antibiotics such as penicillin to bleomycin used to treat cancer and amphotericin for fungal infections. In a context of increasing diseases caused by resistant microorganisms, soil biodiversity has enormous potential to provide new drugs to combat them.

The way forward
Generally, there is a lack of detailed data, policies and actions on soil biodiversity at local, national, regional, and global levels. In order to better understand the threats to soil biodiversity and implement relevant policies and regulations, it is crucial to invest in harmonized soil biodiversity assessments worldwide, standardize sampling and analysis protocols to enable the collection of large comparable datasets, and promote the use of efficient monitoring tools to record changes in soil biodiversity.

The publication also underscores the need to promote innovative technologies in soil management. For instance, new molecular techniques using next-generation molecular sequencing allow a better understanding of soil organisms and the effects these organisms may have on associated cropping systems.