Effect of crop cultivation on the soil carbon stock in mine dumps of the Loess Plateau, China

Jiaxin Mi; Huping Hou; Simit Raval; Yongjun Yang; Shaoliang Zhang; Yifei Hua; Chen Wang; Fuyao Chen

doi:10.1016/j.scitotenv.2020.139809

Effect of crop cultivation on the soil carbon stock in mine dumps of the Loess Plateau, China

Sci Total Environ. 2020 Nov 1:741:139809. doi: 10.1016/j.scitotenv.2020.139809. Epub 2020 Jun 6.

Authors

Jiaxin Mi¹, Huping Hou², Simit Raval³, Yongjun Yang⁴, Shaoliang Zhang⁵, Yifei Hua⁶, Chen Wang⁷, Fuyao Chen⁷

Affiliations

¹ School of Environment Science and Spatial Informatics, China University of Mining and Technology, Xuzhou 221008, China; School of Minerals and Energy Resources Engineering, University of New South Wales, Sydney, NSW 2052, Australia.
² School of Environment Science and Spatial Informatics, China University of Mining and Technology, Xuzhou 221008, China; Think Tank of Jiangsu for Natural Resource, China University of Mining and Technology, Xuzhou 221116, China.
³ School of Minerals and Energy Resources Engineering, University of New South Wales, Sydney, NSW 2052, Australia.
⁴ School of Environment Science and Spatial Informatics, China University of Mining and Technology, Xuzhou 221008, China; Engineering Research Center of Ministry of Education for Mine Ecological Restoration, China University of Mining and Technology, Xuzhou 221116, China.
⁵ School of Environment Science and Spatial Informatics, China University of Mining and Technology, Xuzhou 221008, China; Think Tank of Jiangsu for Natural Resource, China University of Mining and Technology, Xuzhou 221116, China; Engineering Research Center of Ministry of Education for Mine Ecological Restoration, China University of Mining and Technology, Xuzhou 221116, China. Electronic address: slzhang@cumt.edu.cn.
⁶ School of Management, China University of Mining and Technology, Xuzhou 221116, China.
⁷ School of Environment Science and Spatial Informatics, China University of Mining and Technology, Xuzhou 221008, China.

PMID: 32570064
DOI: 10.1016/j.scitotenv.2020.139809

Abstract

In the ecological restoration of mine dumps, soil carbon stock (SCS) improvement is an important issue. The type of land use and management approach taken can have a great influence on this issue. On the Loess Plateau, different crops have been cultivated on reclaimed land; however, the effect of long-term crop cultivation on SCS is poorly understood. To address this issue, a field investigation of mine dumps was performed at the Kee Open Pit Mine in Shanxi Province, China. Four sites utilizing different land management methods were analyzed: no reclamation (NR), reclamation with no crop cultivation (NC), and reclamation followed by 11 or 27 years crop cultivation (RC-11 and RC-27, respectively). SCS, associated soil properties (total nitrogen (TN), total phosphorus (TP), total potassium (TK), moisture content (MoiC), and pH), plant community (species composition, plant diversity, and traits), and microbial community operational taxonomic units (OTUs) of fungi and bacteria were determined by field investigation and laboratory analysis. Redundancy analysis was used to show the relationship between SCS and other environmental variables. Results varied by soil depth. At the depth range of 0-20 cm, the SCS of RC-11 was significantly greater compared to that in NR and NC, by 14.64- and 2.25-fold, respectively; whereas compared to RC-27, it was higher by 52.78%. At the depth of 20-40 cm, NC has the largest SCS; the SCS of RC-27 was the lowest, which was less compared to that in NC by 43.64%. Redundancy analysis showed a positive relationship between the SCS and TN, TP, MoiC, as well as average plant coverage, while the bacterial OTUs were negatively related with the SCS. This research suggests the potential of mine dumps for crop cultivation, which could improve the SCS of the mining area on the Loess Plateau.

Keywords: Crop cultivation; Loess Plateau; Mine dump; Soil carbon stock; Spontaneous succession.