Long-term contrasting tillage in Cambisol: effect on water-stable aggregates, macropore network and soil chemical properties

. Abstract. The aggregate stability of the soil is subject to the influence of anthropogenic factors and is of great interest all over the world. The research aimed to quantify the correlations between soil organic carbon, total nitrogen, total phosphorus, and total potassium, soil macropore parameters and water-stable aggregates under no-tillage and conventional tillage in Cambisol. The content of water-stable aggregates and macroporosity tended to increase in the following order: conventional tillage (returned residues) < conventional tillage (removed residues) < no-tillage (removed residues) < no-tillage (returned residues) in both fertilizations. The relationships between total nitrogen and various soil factors were investigated: soil organic carbon (r = 0.65, p < 0.05), total phosphorus (r = 0.65, p < 0.05), were statistically significant. Soil organic carbon and total nitrogen were positively correlated with water-stable aggregates (r = 0.81, p < 0.01 and r = 0.68, p < 0.05, respectively), whereas the relationship between total potassium and water-stable aggregates was negative. The relationship between total phosphorus and water-stable aggregates (r = 0.62, p < 0.05) was positive. The soil chemical properties, macropores and water-stable aggregates that were averaged across the residues and fertilizations were higher in no-tillage than in conventional tillage. Soil organic carbon, total nitrogen and total phosphorus all had a positive direct influence on the formation of water-stable aggregates under different tillage conditions. Since our results are largely based on correlations, the mechanisms of interaction between the soil chemical properties, water-stable aggregates and the formation of pores in the soil need to be explored further in future investigations.