Soil food web properties explain ecosystem services across European land use systems

TLDR

Intensive land use reduces soil biota diversity and abundance, impairing ecosystem processes and services, yet field evidence linking biota to these processes remains limited. The study quantified how land‑use‑driven differences in soil food web composition across four European countries affect soil functioning and ecosystem services. We assessed soil food web composition in intensive wheat rotation, extensive rotation, and permanent grassland across four countries, linking it to soil functioning and ecosystem services. Intensive wheat rotation reduced all soil food web components, while soil food web properties consistently predicted C and N cycling across land uses and regions; carbon loss correlated with earthworm biomass and fungal/bacterial ratios, nitrogen cycling was driven by mycorrhizal fungi and bacterial biomass, highlighting the need to include soil biota in C and N models and to conserve soil biodiversity.

Abstract

Intensive land use reduces the diversity and abundance of many soil biota, with consequences for the processes that they govern and the ecosystem services that these processes underpin. Relationships between soil biota and ecosystem processes have mostly been found in laboratory experiments and rarely are found in the field. Here, we quantified, across four countries of contrasting climatic and soil conditions in Europe, how differences in soil food web composition resulting from land use systems (intensive wheat rotation, extensive rotation, and permanent grassland) influence the functioning of soils and the ecosystem services that they deliver. Intensive wheat rotation consistently reduced the biomass of all components of the soil food web across all countries. Soil food web properties strongly and consistently predicted processes of C and N cycling across land use systems and geographic locations, and they were a better predictor of these processes than land use. Processes of carbon loss increased with soil food web properties that correlated with soil C content, such as earthworm biomass and fungal/bacterial energy channel ratio, and were greatest in permanent grassland. In contrast, processes of N cycling were explained by soil food web properties independent of land use, such as arbuscular mycorrhizal fungi and bacterial channel biomass. Our quantification of the contribution of soil organisms to processes of C and N cycling across land use systems and geographic locations shows that soil biota need to be included in C and N cycling models and highlights the need to map and conserve soil biodiversity across the world.