4 December 2020, Rome - Soil organisms play a crucial role in boosting food production, enhancing nutritious diets, preserving human health, remediating polluted sites and combating climate change, but their contribution remains largely underestimated, FAO said today in its first ever report on "The State of Knowledge of Soil Biodiversity". The report was launched today 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.
"Soil biodiversity and sustainable soil management is a prerequisite for the achievement of many of the Sustainable Development Goals," said FAO Deputy Director-General Maria Helena Semedo. "Therefore, data and information on soil biodiversity, from the national to the global level, are necessary in order to efficiently plan management strategies on a subject that is still poorly known".
"We hope that the knowledge contained in this report will facilitate the assessment of the state of soil biodiversity as an integral part of national- and regional-level biodiversity reporting and any soil surveys," she added.
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.
The report defines soil biodiversity as the variety of life belowground, 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. These include a wide range of organisms, from unicellular and microscopic forms to invertebrates such as nematodes, earthworms, arthropods and their larval stages, as well as mammals, reptiles, and amphibians that spend a large part of their life belowground, and a great diversity of algae and fungi.
Threats to soil biodiversity
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. These transformations are also vital for the filtration, degradation, and immobilization of contaminants in water and soil. In addition, the soils diversity contributes to improving the control, prevention, or suppression of pests and pathogens.
However, the important role of soil biodiversity in ensuring sustainable agri-food systems can be threatened by human activities, climate change and natural disasters.
The overuse and misuse of agrochemicals remains one of the major drivers to soil biodiversity loss, thus reducing the potential of soil biodiversity for a sustainable agriculture and food security.
Other examples include deforestation, urbanization, agricultural intensification, loss of soil organic matter/carbon, soil structure degradation, surface sealing, soil acidification, pollution, salinization, sodification, wildfires, erosion, and landslides.
Soils' potential to mitigate climate change
Nature-based solutions involving soil microorganisms have a significant potential to mitigate climate change. They play a key role in carbon sequestration and reducing greenhouse gas emissions. Part of the anthropogenic carbon dioxide emissions can be absorbed by plants and stored in soils through microbial decomposition, which can allow the retention of soil carbon for long periods of time.
The report finds that farming activities are the biggest source of carbon dioxide and nitrous oxide gases emitted by soils, which derive from the overuse or misuse of nitrogen-containing fertilizers.
Soil biodiversity and human well-being
Soil biodiversity supports human health, both directly and indirectly, through disease regulation and food production. Several soil bacteria and fungi are traditionally used in the production of soy sauce, cheese, wine, and other fermented food and beverages. The relationship between plant roots and soil biodiversity enables plants to produce chemicals such as antioxidants that protect them from pests and other stressors.
When we consume these plants, the antioxidants benefit us by stimulating our immune system and contributing to hormone regulation. Soil microorganisms can also help prevent chronic inflammatory diseases, including allergy, asthma, autoimmune diseases, inflammatory bowel disease, and depression.
Furthermore, 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. The report highlights the need to promote the necessary shift to include biological indicators of soil health along with physical and chemical ones.
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.
According to the report, the adoption of sustainable soil management practices by farmers, as a basic premise for preserving soil biodiversity, remains low due to the lack of technical support, provision of incentives and enabling environments, and needs to be scaled up.
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.
Therefore, it remains of paramount importance to strengthen education and capacity building in the adoption of innovative tools to contribute to human, plant, and soil health.
The key findings of the report will be presented today at 13h00 Rome time at the World Soil Day virtual ceremony. During the ceremony, the Glinka World Soil Prize 2020 will be awarded to an Italian agricultural scientist and action leader in soil Luca Montanarella, and the King Bhumibol World Soil Day Award will be given to the Indian Council of Agricultural Research (ICAR). Furthermore, in the understanding that we cannot properly manage something we do not know, the Armenian Soil Information System will be launched during the event. The event will be webcast live here
