EGU25-11594, updated on 15 Mar 2025
https://doi.org/10.5194/egusphere-egu25-11594
EGU General Assembly 2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
From pesticides to compost: How agricultural management practices shape soil microbial communities and soil functions across Swiss farms
Florian Walder1 and Marcel van der Heijden1,2
Florian Walder and Marcel van der Heijden
  • 1Agroscope, Agroecology and Environment, Switzerland (florian.walder@agroscope.admin.ch)
  • 2University of Zurich, Department of Plant and Microbial, Switzerland

A critical asset of healthy soils is a rich and functionally diverse microbiota, yet many agricultural practices - including frequent pesticide use and insufficient organic amendments - risk compromising this biological foundation. In this contribution, we present results from two complementary studies conducted on more than 100 farms in Switzerland to investigate how pesticide application and compost use affect the diversity, composition and structure of soil microbial communities. Using a combination of molecular analyses (16S/ITS rRNA amplicon sequencing, quantitative PCR of functional genes), soil physicochemical properties and indicators for soil functions, we found that pesticide residues are associated with shifts in microbial community composition and, in some cases, reduced bacterial diversity. Conversely, farms that regularly apply compost show increased fungal richness and more complex microbial networks than reference farms. By linking these changes in microbial community traits to soil functional indicators - such as soil respiration and aggregate stability - we could shed light on the interrelationships of soil biodiversity, physicochemical properties, and soil functions, as well as the influence of agricultural management.

How to cite: Walder, F. and van der Heijden, M.: From pesticides to compost: How agricultural management practices shape soil microbial communities and soil functions across Swiss farms, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-11594, https://doi.org/10.5194/egusphere-egu25-11594, 2025.