不同工程复垦措施对晋东南采煤沉陷区土壤质量演变特征的影响

为了揭示不同工程复垦措施下采煤沉陷区土壤质量的演变特征,基于10年的长期定位试验,研究了晋东南采煤沉陷区在表土剥离和混推复垦两种工程复垦方式下,10年间土壤的理化性质、微生物群落结构及土地生产力的变化特征。结果表明：复垦初期,表土剥离处理的复垦土壤理化性质、土地产出能力均显著高于混推复垦。复垦7年时,土壤的物理性质、微生物群落结构组成与多样性和土地产出能力基本一致,差异不显著。复垦10年间,0~20 cm土层土壤养分含量始终表现为表土剥离>混推复垦;10年间表土剥离较混推复垦收益累计增加6609元/hm²,因此,表土剥离复垦方式在保持耕层土壤肥力及综合收益上要优于混推复垦。但复垦10年后,2种复垦方式土地生产力和肥力水平均很低,说明复垦方式只是矿区复垦过程的一个前置环节,矿区土壤的生态恢复是必须要结合施肥措施进行。

Effects of Engineering Reclamation Measures on Soil Quality Evolution Characteristics of Mining Subsidence Area in Southeastern Shanxi

To reveal the evolution characteristics of soil quality of coal mining subsidence area under different engineering reclamation measures, based on a 10 years long-term test, the authors studied the soil physical and chemical properties, microbial community structure and the change characteristics of land productivity in coal mining subsidence area in the southeast Shanxi, with topsoil stripping and mixed pushing engineering reclamation. The results showed that in the beginning of the reclamation, the physical and chemical properties of reclaimed soil and land productivity under topsoil stripping reclamation were significantly higher than that of mixed pushing reclamation. After 7 years of reclamation, the physical properties, microbial community structure composition and diversity and land productivity of the soil were basically the same between the two measures, and the difference was not significant. During the 10 years of reclamation, the soil nutrient content in 0-20 cm soil layer was always shown as topsoil stripping > mixed reclamation. During the 10 years, the cumulative return of topsoil stripping increased by 6609 yuan/hm² compared with that of mixed pushing reclamation. Topsoil stripping reclamation was better than mixed pushing reclamation in maintaining topsoil fertility and comprehensive return. However, after 10 years of reclamation, the land productivity and fertility level of the two reclamation measures were very low, indicating that the reclamation method was only a leading link in the mining area reclamation process, and the ecological restoration of the soil in the mining area must be combined with fertilization measures.