山西平朔露天矿区复垦农用地表层土壤质量差异对比

以复垦农用地为研究对象，以原地貌未受损农用地和排土场未复垦地作为对照，共选择18个样地，对比研究复垦农用地、未复垦地及原地貌未受损农用地的土壤容重、田间持水量、pH值、有机质、全氮、全钾、有效磷、速效钾的差异，揭示复垦农用地土壤重构的过程及变异的规律。结果表明：（1）复垦农用地土壤容重、田间持水量、pH值、全钾、有效磷、速效钾的均值都略高于未受损农用地；而复垦农用地有机质、全氮的均值都略低于未受损农用地。（2）复垦农用地和未受损农用地在0-10cm的土壤容重及pH值均略低于10～20cm土层；0～10cm的土壤肥力指标均值略高于10～20em土层。（3）在0～10cm土层，复垦耕地和复垦林地的相关土壤理化性质要优于未受损耕地；在10—20cm，复垦林地土壤理化性质基本上优于未受损耕地。（4）复垦13年的耕地土壤容重、速效钾与未受损耕地差异不显著；复垦22年林地的单个土壤理化指标基本上优于复垦19年林地，复垦19年林地的单个土壤理化指标基本上优于未受损林地。

Soil Quality of Surface Reclaimed Farmland in Large Open-cast Mining Area of Shanxi Province

To assess the impacts of land reclamation on soil quality in mining area, we compared the physicochemical properties of surface soils from reclaimed farmlands with those from the un-reclaimed lands and undamaged farmlands using a total of 18 plots with different land types and reclamation duration. All reclaimed farmlands had higher soil bulk density, field moisture capacity, pH, total phosphorus, total potassium, available phosphorus and available potassium, but lower organic matter and total nitrogen than the undamaged farmlands did. For both re- claimed and undamaged agriculture lands, soils had lower density and pH, but better soil fertility at 0-10 cm than at 10-20 em layers. Most of the physieoehemical properties of soils at the depth of 0~10 cm were higher in the reclaimed cultivated lands and reclaimed woodlands than in the undamaged cultivated lands. Soil bulk density and available potassium of the cultivated lands with 13 year reclamation were not significantly different from those of the undamaged farmlands. Most of the physicochemical properties of the woodlands with 19 years reclamation were better than those of the undamaged woodlands. Taking together, reclaiming lands in mining areas would improve soil quality.