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

Abstract

While the Convention on Biological Diversity employs a habitat‐oriented definition of soil biodiversity including all kinds of species living in soil, the Food and Agriculture Organization, since 2002 assigned to safeguard soil biodiversity, excludes them by focusing on species directly providing four ecosystem services contributing to soil quality and functions: nutrient cycling, regulation of water flow and storage, soil structure maintenance and erosion control, and carbon storage and regulation of atmospheric composition. Many solitary wasps and 70% of wild bees nest below ground and require protection during this long and crucial period of their lifecycle. Recent research has demonstrated the extent of threats to which ground‐nesting pollinators are exposed, for example, chemicals and deep tillage. 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 would lose all ecosystem services provided by these flowering plants, for example, litter, shade, roots for habitats, and erosion control. Above‐ and belowground biota are in constant interaction. Therefore, and in line with the Convention's definition, the key stakeholder, the Food and Agriculture Organization should protect ground‐nesting pollinators explicitly within soil biodiversity conservation.

Location and Creation of Nest Sites for Ground-Nesting Bees in Apple Orchards

“…To date, there is one study to suggest that glyphosate may be detrimental to the reproductive success of solitary bees [ 51 ]. A recent review by Christmann [ 52 ] highlighted that 70% of wild bees nest below-ground and are at risk from chemicals, soil compaction and deep tillage. Deep tillage, reaching 15–30 cm deep, can destroy nests and prevent around 50% of the emergence of ground-nesting bees [ 53 , 54 ].…”

Native Bee Habitat Restoration- Key Ecological Considerations from Recent Literature

“…Nawaz et al (2013) found that soil compaction changed the physical properties of soil, resulting in root deformation, reduced plant growth, decreased germination rates, and increased mortality rates. In addition to affecting plant growth, heavy machinery can threaten bee ground-nest site availability (Potts and Willmer, 1997;Christmann, 2022). Many species of ground-nesting bees require specific soil characteristics to build their nests (Antoine and Forrest, 2020).…”

Diversity and Relative Abundance of Insect Pollinators in Moroccan Agroecosystems

“…For example, Lasioglossum and Andrena were the most abundant and species rich bee genera recorded in this study. These ground nesting bees could be at risk from intensive agriculture because of deep tillage (Ullmann et al, 2016;Christmann, 2022), soil compaction by heavy machinery, accumulation of pesticides as well as the combined effects of these factors. Reducing machinery or adopting no tillage in farms could conserve ground nesting bees (Shuler et al, 2005).…”

“…Reducing machinery or adopting no tillage in farms could conserve ground nesting bees (Shuler et al, 2005). Assessment of pesticide impact and risk to solitary ground-nesting bees as demonstrated by Christmann (2022), may be particularly important for the protection of pollinators in developing countries with high pesticide use (Dicks et al, 2021). For faba bean, cherry and apple that bloom in early season, seeding adequate complementary flowering crops (Christmann and Aw-Hassan, 2012;Sentil et al, 2021), wildflowers strips (Garibaldi et al, 2011;Sutter et al, 2017;Muñoz et al, 2021) or hedgerows (Morandin and Kremen, 2013) may help to attract early flying bees like the genera Eucera, Anthophora, and Bombus and help to conserve these bees in the agricultural landscape.…”