Abstract:[Objective] The carbon sink function of terraces and their characteristics were analyzed and discussed to provide a scientific reference for clarifying the carbon sink function, consolidating and enhancing the carbon sink capacity of ecosystems, and researching and compiling a carbon sink methodology for terraces. [Methods] Terraces with the operational ages of 1—7 a (T5), 8—12 a (T10), 13—17 a (T15), 18—22 a (T20), and 23—27 a (T25) were selected at Wuqi County, Shaanxi Province in the loess hilly and gully region. Slope croplands without soil and water conservation measures were selected for baseline comparison to study the capabilities of terraces in terms of carbon preservation, emission reduction, and carbon sequestration across different years. [Results] ① After the transformation of sloped croplands into terraces, an increase was observed in carbon preservation, emission reduction, and carbon sequestration. Annual carbon preservation, emission reduction, and carbon sequestration (0—100 cm) were 0.26, 0.05 and 1.36 t/hm2 respectively. ② Each soil layer of the terraces contributed certain benefits; the carbon sequestration benefits of the surface (0—40 cm) and deep (40—100 cm) soil layers accounted for 61.50% and 38.50% of the entire soil layer, respectively. ③ The benefits of the terrace surface soil significantly increased with the increase in the operation year of the terrace, while the benefits of deep soil were slightly improved but remained stable on the whole. The rate of carbon sequestration in the surface soil increased from 16.30% at T5 to 51.34% at T25 and that in the deep soil increased from 14.00% at T5 to 23.66% at T25. [Conclusion] The terraces in the loess hilly and gully regions exhibited significant carbon sink functions, including carbon preservation, emission reduction, and carbon sequestration. The proportion of carbon sequestration capacity was the largest within 27 years of terrace operation, and the increase in the surface soil was more significant. The proportion of carbon preservation in the carbon sink capacity of terraces gradually increases with an increase in terrace operation years.