Regard and protect ground-nesting pollinators as part of soil biodiversity

Abstract

While the Convention on Biological Diversity employs a habitat-oriented defini-tion of soil biodiversity including all kinds of species living in soil, the Food andAgriculture Organization, since 2002 assigned to safeguard soil biodiversity,excludes them by focusing on species directly providing four ecosystem servicescontributing to soil quality and functions: nutrient cycling, regulation of waterflow and storage, soil structure maintenance and erosion control, and carbon stor-age and regulation of atmospheric composition. Many solitary wasps and 70% ofwild bees nest below ground and require protection during this long and crucialperiod of their lifecycle. Recent research has demonstrated the extent of threats towhich ground-nesting pollinators are exposed, for example, chemicals and deeptillage. Ground-nesting pollinators change soil texture directly by digging cavities,but more importantly by their indirect contribution to soil quality and functions:87% of all flowering plants require pollinators. Without pollinators, soil wouldlose all ecosystem services provided by these flowering plants, for example, litter,shade, roots for habitats, and erosion control. Above- and belowground biota arein constant interaction. Therefore, and in line with the Convention’sdefinition,the key stakeholder, the Food and Agriculture Organization should protectground-nesting pollinators explicitly within soil biodiversity conservation.