The Impact of Long‐Term Tillage Systems on Soil Carbon and Nitrogen Dynamics and Other Nutrient Contents

Different long‐term tillage systems were examined for their effects on the amount of native mycorrhizal spores in the rhizosphere and nonrhizosphere soils, as well as their effects on the organic carbon and mineral nutrient content of the soil. The long‐term study was initiated in 2006, using a Typic Haploxerert soil series, with the current study conducted in 2018–2019 using the Adana‐99 wheat variety. Seven tillage systems were examined: two no‐tills (NT and ST), three reduced tillage systems (RT‐1, RT‐2, and RT‐3), two conventional tillage systems (CT‐1 and CT‐2), and one strategic/occasional tillage system with three replicates as randomized blocks. The effects of tillage management on soil quality parameters were found by analyzing N, P, K, Mg, Ca, Cu, Fe, Zn, and Mn contents, as well as inorganic and organic carbon in soil samples taken before sowing and postharvest. Tillage systems had a significant influence on mineral nutrient concentrations. Reduced and no‐tillage methods, particularly strategic and no‐tillage, contribute positively to soil organic carbon (SOC) sequestration and nutrient retention and the number of mycorrhizae spores. The results show that as the tillage intensity decreased, the soil C, N, K, Ca, and Mg contents increased mycorrhizal spores. The rhizosphere soils under no‐tillage and reduced tillage practices had higher soil carbon content and higher mycorrhizae spore counts at the postharvest stage than soils under conventional tillage (CT) practices. Conclusively, after 13 years of different soil tillage treatments, more carbon was sequestrated under NT than under heavy tillage CT treatment. The ST tillage treatment sequestrated 19.37 Mt SOC (0–15 cm) and 10.06 (15–30 cm) Mt SOC compared with the CT‐1 tillage treatment. Comparing CT treatments, RT tillage and NT maintained higher carbon concentrations of up to 17% and 31%, respectively.