Climate and farming system dominate wheat yield responses across European pedoclimatic zones, despite widespread soil nutrient surpluses

Abstract

Background and aims: European wheat production faces the challenge of maintaining yields while reducing environmental impacts from agrochemicals. Organic farming is often considered a sustainable alternative to promote soil health and reduce chemical inputs. This study assessed nutrient status in wheat soils across nine European pedoclimatic zones, comparing conventional and organic systems and evaluating management practices such as crop rotation, tillage and fertilization type. Methods: A total of 188 soils were analyzed for macro- and micronutrients, and wheat yield data were evaluated in relation to soil nutrients, climate, wheat type (winter- vs. spring-sown), and management using correlation, random forest, and regression analyses. Results: Soils showed excess P, K, Mg, Cu, Fe, Mn, and Zn, but S and B deficiencies. Organic systems increased total N, while conventional farming enhanced nitrate, sulfate, and boron. Wheat yield was primarily driven by temperature, precipitation, wheat type (winter- vs. spring-sown), and farming system, with additional contributions from fertilization and nutrients (particularly exchangeable Ca, Fe, Mn, and Zn). On average, organic yields were 37% significantly lower than conventional, but these differences were smaller in Mediterranean zones due to reduced pest pressure and improved water retention and infiltration. Practices such as crop rotation, residue incorporation, and reduced tillage positively influenced yield. Conclusion: Organic farming supports soil health and sustainable use of resources, but may reduce wheat yield in northern and central European pedoclimatic zones. Tailored nutrient management combined with agronomic practices can enhance productivity while minimizing environmental impacts, especially in climate-stressed regions.