生态脆弱区复垦排土场干扰类型划分及影响因素分析

Classification of disturbance types and influencing factors of reclamation dump in ecological fragile area

露天煤矿排土场复垦效果对重建生态系统稳定性具有关键作用,多通过复垦后植被变化的长期监测分析复垦效果。生态脆弱区露天煤矿排土场易受到外界干扰,恢复稳定性呈现较大空间差异,亟需探究排土场干扰类型划分方法及其影响机理。以长时间序列中最优状态下植被的结构和功能特征为比照标准,在前期构建复垦排土场干扰指数(DRDI)的基础上,进一步根据干扰动态特征划分干扰类型,并分析影响干扰类型的自然和人为因素。选择山西省平朔安太堡露天煤矿的4个排土场作为研究区,其复垦类型、复垦开始时间、持续时间各异。基于Landsat遥感影像,计算研究区1986—2017年的DRDI;干扰类型划分为持续干扰型、复垦稳定型、干扰恢复型和复垦退化型;从地形、土壤条件、复垦类型等方面选取可能对干扰类型存在影响的因素进行地理探测器分析。研究结果表明:复垦排土场内部干扰发生后呈现不同动态特征,干扰类型存在空间异质性,小尺度下同一排土场内同一类型在空间分布上存在着空间聚集,以复垦稳定性、干扰恢复型最为明显;单因子对于排土场复垦的影响程度强弱依次为复垦类型、土壤理化性质及地形,同时因子间均存在着相互影响进而影响了复垦;复垦时间分别与全氮、高程、速效钾、有机碳共同作用后对干扰类型的影响较大,全氮与pH的交互作用次之;因子间相互作用方式以非线性增强为主,但复垦时间、植被类型通过影响土壤要素等因子进而影响复垦,以线性增强为主。研究结果揭示了小尺度内矿区扰动与复垦存在的空间异质性及其与影响因子之间的关系,为矿区复垦工作提供建议和参考。

The reclamation effect of open-pit mining reclamation dumps plays a key role in rebuilding the stability of the ecosystem,and the reclamation effect is mostly analyzed through long-term monitoring of vegetation changes after reclamation.The open-pit mining dumps in ecologically fragile areas are susceptible to external disturbances,and the restoration stability presents large spatial differences.Taking the structural and functional characteristics of vegetation in the optimal state in the long-term series as the comparison standard,on the ba⁃sis of the early construction of the Reclamation Dump Disturbance Index(DRDI),the disturbance types are further divided according to the dynamic characteristics of disturbance.And analyze natural and human-made factors that influence disturbance types.Four dumps of the Antaibao open coal mine in Pingshuo,Shanxi Province were selected as the study area.Their reclamation types,reclamation start times,and durations were different.Based on Landsat remote sensing images,calculate the DRDI of the research area from 1986 to 2017.The disturbance types were divided into continuous disturbance type,reclamation stable type,disturbance recovery type and reclamation de⁃generative type.From the aspects of terrain,soil conditions,and reclamation types,factors that may have an impact on the type of disturb⁃ance are selected for GeoDetector analysis.The research results show that the internal disturbance of the reclamation dump presents differ⁃ent dynamic characteristics after the occurrence of the disturbance,the type of disturbance has spatial heterogeneity.There is spatial aggre⁃gation of the same type in the spatial distribution of the same soil at a small scale,and the reclamation stable type and disturbance recovery type are the most obvious.The degree of influence of a single factor on the reclamation is followed by the type of reclamation,soil physico⁃chemical properties and topography.At the same time,there is mutual influence among the factors,which affects the reclamation.The rec⁃lamation time has a greater impact on the disturbance type after the combined action of total nitrogen,elevation,available potassium and or⁃ganic carbon,followed by the interaction between total nitrogen and pH.The interaction between factors is mainly nonlinear enhancement.But reclamation time and vegetation type affect reclamation through factors such as soil elements,and linear enhancement is the main meth⁃od.The research results reveal the spatial heterogeneity of the disturbance and reclamation in the small-scale mining area and its relation⁃ship with the influencing factors.Provide suggestions and references for the reclamation of the mining area.