Low-intensity management promotes the soil priming effect in European agroecosystems

Agricultural management is critical in shaping soil carbon (C) stocks, pools and fluxes. The soil priming effect (PE) is known as a key component of the global C cycle that reflects alterations in soil organic carbon (SOC) mineralization induced by fresh C inputs. Here, we show that priming can help to predict soil C content across European Long-Term Experiments (LTEs), a result which was maintained at continental and global scales. Results reveal that lower-intensity management significantly enhances PE in soils from European croplands. Conversely, high-intensity management led to lower or even negative PE. Management intensity influences PE directly through alterations in SOC and indirectly by modifying aggregates stability and microbial biomass. Both fertilization and tillage affect PE, with soils under organic fertilization and no-tillage showing higher values of PE. These findings advance our understanding of the long-term impacts of agricultural management on the C cycle at the continental scale. The priming effect (PE) predicts soil carbon across croplands. Using soils from European long-term experiments, we show that low-intensity management enhances PE, whereas intensive fertilization and tillage reduce it.