Evolution characteristics of soil carbon density after homestead remediation

Abstract

In order to gain an in-depth understanding of the effects of different reclamation years on soil carbon sequestration after remediation of abandoned homesteads, this study relied on the land improvement project carried out in Changchun County, Shaanxi Province, to study the soil carbon density of different reclamation years. The results shown that the total carbon and inorganic carbon content of 0-20cm and 40-60cm soil layers increased steadily with the extension of cultivation time after the rectification of abandoned homesteads. In the 20-40 cm soil layer, the soil total carbon and inorganic carbon content increased firstly, then decreased and then increased with the extension of the cultivation period, especially the total carbon content changed the most. In the 0-40 cm soil layer, the organic carbon showed a tendency to decrease first, and the change trend of the organic carbon content in the 40-60 cm soil layer increased first and then decreased. The trend of carbon density changes was consistent with the trend of carbon content. After 10 years of reclamation compared with before the renovation, soil total carbon and inorganic carbon density increased by 22.93% to 47.72% and 16.11% to 45.30%, respectively, the regularities of vertical distribution was 40-60 cm > 0-20 cm > 20-40 cm. The density of organic carbon increased by 41.12% to 68.27% compared with before the renovation, and the regularities of vertical distribution was 0-20cm>20-40cm>40-60cm. It shows that long-term reclamation after homestead remediation is beneficial to the increase and fixation of surface soil organic carbon.