Environment Research Institute, Shandong University, Qingdao, China.
Lunan Geo-engineering Exploration Institute, Jining, China.
PLoS One. 2023 Feb 21;18(2):e0282014. doi: 10.1371/journal.pone.0282014. eCollection 2023.
The content and composition of soil organic carbon (SOC) can characterize soil carbon storage capacity, which varies significantly between habitats. Ecological restoration in coal mining subsidence land forms a variety of habitats, which are ideal to study the effects of habitats on SOC storage capacity. Based on the analysis of the content and composition of SOC in three habitats (farmland, wetland and lakeside grassland) generated by different restoration time of the farmland which was destroyed by coal mining subsidence, we found that farmland had the highest SOC storage capacity among the three habitats. Both dissolved organic carbon (DOC) and heavy fraction organic carbon (HFOC) exhibited higher concentrations in the farmland (20.29 mg/kg, 6.96 mg/g) than in the wetland (19.62 mg/kg, 2.47 mg/g) or lakeside grassland (5.68 mg/kg, 2.31 mg/g), and the concentrations increased significantly over time, owing to the higher content of nitrogen in the farmland. The wetland and lakeside grassland needed more time than the farmland to recover the SOC storage capacity. The findings illustrate that the SOC storage capacity of farmland destroyed by coal mining subsidence could be restored through ecological restoration and indicate that the recovery rate depends on the reconstructed habitat types, among which farmland shows great advantages mainly due to the nitrogen addition.
土壤有机碳（SOC）的含量和组成可以表征土壤碳储存能力，而不同生境之间的土壤碳储存能力差异显著。煤矿塌陷区生态修复形成了多种生境，非常适合研究生境对 SOC 储存能力的影响。本研究通过分析采煤塌陷破坏农田不同复垦时间形成的三种生境（农田、湿地和湖滨草地）的 SOC 含量和组成，发现农田的 SOC 储存能力最高。溶解有机碳（DOC）和重质有机碳（HFOC）在农田中的浓度（20.29 mg/kg，6.96 mg/g）高于湿地（19.62 mg/kg，2.47 mg/g）或湖滨草地（5.68 mg/kg，2.31 mg/g），且随着时间的推移呈显著增加趋势，这主要是由于农田中氮含量较高。湿地和湖滨草地恢复 SOC 储存能力所需的时间比农田长。研究结果表明，通过生态修复可以恢复采煤塌陷破坏农田的 SOC 储存能力，并且恢复速率取决于重建的生境类型，其中农田由于氮的添加具有很大的优势。
