Map of soil biodiversity, published in the Global Soil Biodiversity Atlas by the European Commission’s Joint Research Centre, as part of the Global Soil Diversity initiative.

This article originally appeared in the June/July issue of Position magazine. To read the article in full and keep up to date on all things surveying and spatial, be sure to subscribe to Position magazine.

One teaspoon of soil contains thousands of living creatures, and scientists have just mapped every single one of them on a global scale. Or, at least, they have for the first time estimated how diverse soil life is across the globe. The above map builds on this, showing the regions facing the greatest threats to soil diversity, based on a wide range of anthropogenic and natural influences.

Soil is by far the most biologically diverse part of the earth and includes earthworms, spiders, ants, beetles, collembolans, mites, nematodes, fungi, bacteria and other organisms. We are familiar with flora and fauna, but life below the surface extends farther than you might expect. Nematodes, for example, are roundworms that have been found up to 3.6 kilometres below the surface.

Soil organisms provide essential ecosystem services to human beings and the environment, including the support of biodiversity and the regulation of climate. Recent studies have also found that the aboveground biodiversity of a region is strongly correlated in a feedback loop process to the soil health in the same area.

To protect soil’s vital role, the dense 180-page Global Soil Biodiversity Atlas compiles the extent of human knowledge about Earth’s most complex section of the biosphere with countless maps, diagrams and photographs and contributions from over 121 experts from 26 countries. As you might expect, the highest diversity soils are located where you will find the highest biodiversity of plants and animals. What may prove more useful, however, is a quantification of the threat to this diversity.

Map of potential threats to soil biodiversity, published in the Global Soil Biodiversity Atlas by the European Commission’s Joint Research Centre, as part of the Global Soil Diversity initiative.

To create the above map, the following was taken into account: loss of aboveground biodiversity, plant species loss, pollution and nutrient overloading, agricultural use, cropland percentage cover, overgrazing, fire risk, soil erosion, desertification vulnerability and the effects of climate change on aridity. All datasets were then harmonised on a 0-1 scale and summed, with total scores categorised into the accompanying scale.

The areas with the lowest level of risk are generally less exposed to both direct anthropogenic effects such as agriculture; as well as indirect anthropogenic effects such as climate change. At the opposite end of the scale, the areas with highest risk are those with the greatest exposure to human activities.

Since there is still much to learn about soil life and the impacts on its health are multifarious, the authors point out that the potential rather than the actual level of threat has been mapped. The practical use of this type of map depends on the simultaneous development of systems to monitor soil biodiversity distribution. Despite its limitations, this map represents the first preliminary assessment of the risk to soil diversity on a global scale.

To learn more about this map and the complex nature of soil life, access the Global Soil Biodiversity Atlas.

This article originally appeared in the June/July issue of Position magazine.