1,2,3,4,5,6,8,9,1,2,10- 1Institute of Geo‐Hydroinformatics, Hamburg University of Technology, Hamburg, Germany
- 2United Nations University Hub on Engineering to Face Climate Change at the Hamburg University of Technology, United Nations University Institute for Water, Environment and Health (UNU‐INWEH), Hamburg, Germany
- 3The Climate and Environmental Research Institute NILU, Kjeller, Norway
- 4Department of Environmental Systems Science, Swiss Federal Institute of Technology, Zürich, Switzerland
- 5Department of Civil and Environmental Engineering, University of Nevada, Reno, Nevada, USA
- 6European Commission, Joint Research Centre (JRC), Ispra, Italy
- 7European Dynamics, Brussels, Belgium
- 8Departamento de Ecología y Biología Animal, Universidade de Vigo, Vigo, Spain
- 9UK Centre for Ecology and Hydrology, Bangor, UK
- 10United Nations University Institute for Water, Environment and Health (UNU-INWEH), Richmond Hill, Ontario, Canada
The soil microbiome provides indispensable ecosystem services, including nutrient and organic matter cycling, affecting exchange of energy, water, and carbon at the land-atmosphere interface, as well as provisioning an important environmental resilience layer through buffering natural and anthropogenic stressors. We applied generalized additive models (GAMs) to the largest methodologically consistent dataset of soil eDNA at continental scale. Based on colocated eDNA and soil parameter measurements from the LUCAS 2018 soil biodiversity dataset (Labouyrie et al., 2023; Orgiazzi et al., 2022) and ERA5-Land climate reanalysis data (Muñoz Sabater, 2019) for the 30-year period pre-dating sample collection (1988–2017), we (i) identify key drivers shaping the composition of soil bacterial communities, (ii) quantify changes in soil bacterial richness and diversity forced by soil properties, climatic effects, and anthropogenic pressures, and (iii) assess interaction effects between the different drivers. Multiple feature selection methodologies were employed and cross-checked to reduce the number of predictors without conceding prediction accuracy. A GAM including pH, electrical conductivity, and top layer bulk density (0–10 cm) as covariates can explain 73.3% of variance (adjusted R² = 0.727) in the Shannon entropy of samples. While land cover is commonly considered an important categorical determinant of soil bacterial diversity, our results suggest that land cover per se is no immediate factor, but instead land cover types constrain the physicochemical habitats on site, which are in turn the immediate drivers of bacterial diversity.
References
Labouyrie, M., Ballabio, C., Romero, F., Panagos, P., Jones, A., Schmid, M. W., Mikryukov, V., Dulya, O., Tedersoo, L., Bahram, M., Lugato, E., Van Der Heijden, M. G. A., & Orgiazzi, A. (2023). Patterns in soil microbial diversity across Europe. Nature Communications, 14(1), 3311. https://doi.org/10.1038/s41467-023-37937-4
Muñoz Sabater, J. (2019). ERA5-Land monthly averaged data from 1950 to present [Dataset]. Copernicus Climate Change Service (C3S) Climate Data Store (CDS). https://doi.org/10.24381/CDS.68D2BB30
Orgiazzi, A., Panagos, P., Fernández‐Ugalde, O., Wojda, P., Labouyrie, M., Ballabio, C., Franco, A., Pistocchi, A., Montanarella, L., & Jones, A. (2022). LUCAS Soil Biodiversity and LUCAS Soil Pesticides, new tools for research and policy development. European Journal of Soil Science, 73(5), e13299. https://doi.org/10.1111/ejss.13299
How to cite: Heintze, P., Hassani, A., Or, D., Panagos, P., Orgiazzi, A., Labouyrie, M., Köninger, J., Lebron, I., Robinson, D. A., and Shokri, N.: Generalized additive models confirm pH and emphasize electrical conductivity as key drivers of European soil bacterial diversity, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-1134, https://doi.org/10.5194/egusphere-egu26-1134, 2026.
