You don’t necessarily want to find them in a salad, but they make a significant contribution to ensuring that it is on your plate: the contribution of earthworms to world nutrition may be significantly greater than previously thought. After one now in the specialist magazine Nature Communications published study The arthropods enable the production of 140 million tons of food worldwide every year, including 6.5 percent of global grain and 2.3 percent of vegetable production. This roughly corresponds to Russia’s share of this production, reports the team led by agricultural economist Steven Fonte from Colorado State University.
The work of the worms underground is particularly important in southern countries, probably because farmers there have less access to fertilizer and pesticides. In Latin America, the worms contribute to eight percent of grain production, and in sub-Saharan Africa the figure is even ten percent.
Perhaps there are organisms that are even more important to soil productivity
The worm assessment is based on an analysis of data on earthworm populations, soil properties, fertilizer rates and crop results. “This is the first attempt that I know of where you look at the biodiversity of a patch of earth and then say, OK, this is its contribution on a global scale,” Steven Fonte said in a statement.
It has long been known that earthworms contribute to plant growth in a variety of ways. They loosen the soil, contribute to water retention and help process organic material so that nutrients reach the plants better. Some studies suggest that the worms also promote the production of growth hormones and help plants defend themselves against pathogenic soil germs. Some authors estimate that earthworms increase plant productivity by up to 25 percent.
“Earthworms can be particularly helpful in regions where fewer chemicals can be used,” says Fonte. The importance of healthy soils is still underestimated. He does not advocate settling earthworms in new areas. But we should support them where they already live. And science should generally research the importance of soil organisms for agriculture. “Perhaps there are other organisms, particularly microbial communities, that are even more important.”