黄土露天矿区排土场重构土壤典型物理性质空间差异分析

Changes of Typical Physical Properties of Reclaimed Mine Soil in the Dump Site of Loess Open Mining Area

土壤典型物理性质决定了土壤的肥力状况,同时也影响植物群落的生长。目前矿区复垦方面的研究大多为研究土壤物理性质的空间差异或是植被盖度对表层土壤物理性质的影响,很少有针对不同植被覆盖类型对重构土壤物理性质的影响的研究。运用描述性统计分析法、单因素方差分析法等方法研究平朔矿区重构土壤典型物理性质在水平及垂向方向的差异,并依照研究区植被生长状况进行分组,研究不同植被覆盖类型下的土壤物理性质差异。该研究旨在得到土壤性质及植被间的影响机理,对未来复垦工作的土壤重构及植被重建的提供指导。结果表明,(1)土壤典型物理性质在垂向上均属于弱变异,随着深度增加,复垦效果减弱。土壤容重及孔隙度存在层间显著差异,土壤容重随着土壤深度增加增大,土壤孔隙度随着土壤深度增加减小。(2)研究区重构土壤典型物理性质在水平方向均属于中等变异,随着深度减小,各性质的差异减小。(3)不同植被覆盖类型下的土壤容重和孔隙度在0-10 cm及20-60 cm深度存在显著差异,但在各土壤粒级含量上无显著差异。研究区分布最多的土质类型是壤土。乔木植被生长有助于土壤粒级的减小,草本植被对浅层土壤物理性质改良效果优于深层土壤。未来在进行植被重建工程时应适当根据实地土壤质地情况选择适宜植被。

Soil typical physical properties determine soil fertility and affect plant communities’growth.At present,most studies on reclamation in mining areas focus on the spatial differences of soil physical properties or the impact of vegetation coverage on topsoil physical properties,but there are few studies on differences of soil physical properties under different vegetation types.We used descriptive statistics analysis and single factor variance to research the differences in vertical and horizontal direction of soil physical properties after reclamation in Pingshuo mining area,and grouped by the growth condition of vegetation in the study area to research the differences of soil physical properties under different vegetation types.The aim of the study is to show the influence mechanism between soil properties and vegetation,which provides guidance for the revegetation and soil reclamation in the future.The conclusions of this study are:(1)The soil physical properties in the study area all have weak changes in vertical direction,and the effect of reclamation decreases with the increase of depth.Soil bulk density and porosity have significant difference among layers.Soil bulk density increases with the increase of soil depth.Soil porosity decreases with the increase of soil depth.(2)All the soil typical physical properties in the study area are moderate variation at the same depth,which have been converged after years of reclamation.As the depth decreases,the difference of each property decreases.And(3)soil bulk density and porosity that under different vegetation types are significantly different at the depth of 0-10 cm and 20-60 cm,but there is no significantly difference in sand,silt and clay among groups.Loam is the most abundant soil type in the study area.The trees reduce the soil grain size,and the grass improves the physical properties in shallow soil better than deep soil.It is suggested that suitable plants should be selected according to the soil texture in the future.