Zhu Yanfeng, Wang Liping, Ma Jing, Hua Ziyi, Yang Yongjun, Chen Fu
Engineering Research Center of Ministry of Education for Mine Ecological Restoration, China University of Mining and Technology, Xuzhou 221008, China; School of Environment 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 221008, China.
Sci Total Environ. 2024 Apr 15;921:171179. doi: 10.1016/j.scitotenv.2024.171179. Epub 2024 Feb 23.
Mining activities aggravate the ecological degradation and emission of greenhouse gases throughout the world, thereby affecting the global climate and posing a serious threat to the ecological safety. Vegetation restoration is considered to be an effective and sustainable strategy to improve the post-mining soil quality and functions. However, we still have a limited knowledge of the impact of vegetation restoration on carbon sequestration potential in mining areas. In this pursuit, the present study was envisaged to integrate the findings from studies on soil organic carbon (SOC) sequestration in mining areas under vegetation restoration with field monitoring data. The carbon sequestration potential under vegetation restoration in China's mining areas was estimated by using a machine learning model. The results showed that (1) Vegetation restoration exhibited a consistently positive impact on the changes in the SOC reserves. The carbon sequestration potential was the highest in mixed forests, followed by broad-leaved forests, coniferous forests, grassland, shrubland, and farmland; (2) The number of years of vegetation restoration and mean annual precipitation were found to be the important moderating variables affecting the SOC reserves in reclaimed soils in mining areas; (3) There were significant differences in the SOC sequestration potential under different vegetation restoration scenarios in mining areas in China. The SOC sequestration potential reached up to 9.86 million t C a, when the soil was restored to the initial state. Based on the meta-analysis, the maximal attainable SOC sequestration potential was found to be 4.26 million t C a. The SOC sequestration potential reached the highest level of 12.86 million t C a, when the optimal vegetation type in a given climate was restored. The results indicated the importance of vegetation restoration for improving the soil sequestration potential in mining areas. The time lag in carbon sequestration potential for different vegetation types in mining areas was also revealed. Our findings can assist the development of ecological restoration regimens in mining areas to mitigate the global climate change.
采矿活动加剧了全球范围内的生态退化和温室气体排放，进而影响全球气候，对生态安全构成严重威胁。植被恢复被认为是改善采矿后土壤质量和功能的有效且可持续的策略。然而，我们对植被恢复对矿区碳固存潜力的影响仍知之甚少。在此背景下，本研究旨在将植被恢复下矿区土壤有机碳（SOC）固存研究的结果与实地监测数据相结合。利用机器学习模型估算了中国矿区植被恢复下的碳固存潜力。结果表明：（1）植被恢复对SOC储量变化始终呈现积极影响。碳固存潜力在混交林中最高，其次是阔叶林、针叶林、草地、灌丛和农田；（2）植被恢复年限和年平均降水量是影响矿区复垦土壤中SOC储量的重要调节变量；（3）中国矿区不同植被恢复情景下的SOC固存潜力存在显著差异。当土壤恢复到初始状态时，SOC固存潜力高达986万t C/a。基于荟萃分析，发现可达到的最大SOC固存潜力为426万t C/a。当恢复给定气候条件下的最佳植被类型时，SOC固存潜力达到最高水平1286万t C/a。结果表明了植被恢复对于提高矿区土壤固存潜力的重要性。还揭示了矿区不同植被类型碳固存潜力的时间滞后性。我们的研究结果有助于制定矿区生态恢复方案，以缓解全球气候变化。
