Abstract:The objective of this study was to explore the effect of amendments on soil organic carbon in reclaimed soil. A series of micro field experiments were set to study the effect of peat and humic acid on particulate organic carbon (POC) and mineral-bound organic carbon (MOC) of soil and water-stable aggregates in the soil, which has been reclaimed for seven years in Xiangyuan, Shanxi province. The results showed that peat and humic acid increased the content of water-stable macroaggregates (>0.25 mm) in reclaimed soil. After 6 months, the content of water-stable macroaggregates was decreased and the content of water-stable microaggregates (<0.25 mm) was increased, the change of aggregates with >2 mm and <0.25 mm aggregates were obvious. Compared with the two amendments, the changes of soil macroaggregate and microaggregate in humic acid treatment were greater than those in peat. Peat and humic acid increased the contents of POC and MOC of soil and all level water-stable aggregates in reclaimed soil. When the application ratio was the same, the increases of POC and MOC in soil with humic acid were greater. After applying peat for 6 months and 1 year, the POC contents were 2.14~8.89 g/kg and 1.53~5.00 g/kg, and after applying humic acid for 6 months and 1 year, the POC contents were 8.07~20.12 g/kg and 5.63~19.36 g/kg. After applying peat for 6 months and 1 year, the MOC contents were 4.84~10.51 g/kg and 5.41~8.08 g/kg, and after applying humic acid for 6 months and 1 year, the MOC contents were 9.10~35.34 g/kg and 5.91~30.00 g/kg. However, after 6 months, the contents of POC and MOC were decreased. Peat and humic acid reduced the stability of soil organic carbon, it's not beneficial for the storage of organic carbon.