Profile soil organic and inorganic carbon sequestration in maize cropland after long-term straw return

Promoting cropland carbon (C) sequestration through straw return has always been the focus of numerous studies. However, there is still a lack comprehensive understanding effects on soil organic (SOC) and inorganic (SIC) sequestration. Therefore, present study aims to investigate long-term SOC SIC across 0–100 cm profile in maize planting Northeastern China. The results showed an increasing trend contents following return, while significant decreases were observed surface (0–20 cm) subsoil (20–60 layers, respectively. In addition, stock increased significantly layer by average value 44%, which higher than those other layers. On hand, 24% decreased under-subsoil layers values 53% 33%, Moreover, exchangeable calcium positively correlated with stock, demonstrating contributes highlighted importance for effective strategies promote croplands.