When asked to describe a forest or a meadow, most people would probably begin with the plants, the species diversity, or the color of the foliage. They probably wouldn’t pay much attention to the animals living in the soil.
But a new Yale-led study shows the critical importance of earthworms, beetles, and other tiny creatures to the structure of grasslands and the valuable ecosystem services they provide.
During a 3-year study, researchers found that removing these small animals from the soil of a replicated Scottish sheep meadow altered the plant species that grew in the ecosystem, reduced overall productivity, and produced plants that were less responsive to common agricultural management, such as fertilization.
The results reflect the long-term ecological impacts of land use changes, such as the conversion of forests to agricultural land, researchers say.
“We know these soil animals are important controls on processes which cause nutrients and carbon to cycle in ecosystems, but there was little evidence that human-induced loss of these animals has effects at the level of the whole ecosystem, on services such as agricultural yield,” said Mark Bradford
, an Associate Professor at the Yale School of Forestry & Environmental Studies (F&ES) and lead author of the study published in the Proceedings of the National Academy of Sciences
“Yet that’s exactly what we found.”