The UN Biodiversity Conference (COP15) is set to wrap up after the weekend in Montreal, with delegates discussing global action to reverse biodiversity loss. Any roadmap for change will have to go through the soil: healthy, living soil is key to biodiversity, as NIOO researchers have been stressing.
Biodiversity is one of NIOO's three research themes. From large to tiny organisms, at scales from DNA to landscape, and on land as well as in water. What happens when a species becomes extinct, or when a new species arrives that does not have natural enemies in the Netherlands? And what is the impact of microplastics, light pollution or pharmaceutical residues? NIOO's research focuses on the ecological consequences, but also looks for ways to restore biodiversity.
Soil life going downhill
One of the problems in the Netherlands is the loss of biodiversity in agricultural soil: production is maximised at the expense of the variety of soil animals and soil fungi. "All because of how we produce our food", said NIOO's head of Terrestrial Ecology Wim van der Putten in a recent interview on the main Dutch television news.
"We put lots of fertiliser in the soil, and we cultivate the land very intensively. That is detrimental to the fungal threads that play a vital connecting role, and also to the larger soil animals." It's the soil animals that give the soil the structure it needs, says Van der Putten. So the important thing is not to focus exclusively on production, but also on the soil's other functions.
Soil calibration centre
Soil and soil restoration are key research areas for NIOO's department of Terrestrial Ecology. On its own, and with partners including IUCN NL, WUR and Dutch Butterfly Conservation in the Onder Het Maaiveld (literally: "below ground level") project. The project's aim: to stimulate a living soil.
As part of Onder Het Maaiveld, NIOO has initiated a new Calibration Centre for the Soil, which was opened in 2021 and which is building a reference database for soil biodiversity in the Netherlands. "Together with other organisations, were are working on a structural transformation of the way in which we treat our valuable soil."
Also part of Onder Het Maaiveld are the annual Dutch Soil Animal Days, which were held for the eighth time this year. With more than 2000 citizen scientists taking part across the country, the Soil Animal Days shine a much-deserved spotlight on ten 'ambassadors' of the biodiversity beneath our feet.
There was special attention this year for soil animals in the city: our 'downstairs neighbours'. With more than 84,000 soil animals counted over the past eight years, the results confirm that in urban environments, too, soil animals play a vital role. And the member of the 'tiny ten' found in most Dutch gardens and parks this year was...the earthworm.
Earthworms on top
The long, dry, hot summer in the Netherlands had a major impact. Earthworms were found in 83% of all participating gardens. "But our volunteers only found slugs in 59% of gardens", says soil animal expert Ron de Goede. "Last year that was 76%." Beetles also appeared to be having problems with the dry heat.
Meanwhile, the average number of soil animals per garden was lower than last year: 36. More facts and statistics can be found on the Results Page for the 2022 Soil Animal Days (Dutch only).
Food for thought (and soil)
In Montreal, preserving and restoring biodiversity is the main topic on the table. But no biological wealth aboveground without biological health belowground! It's only when the soil is in good shape that nature and humans can have a strong foundation to build on.