黄土区大型露天矿农业用地格局演变的分析

Pattern succession analysis of agricultural land converted converted from large opencast mine in loess areas

在矿区废弃地的恢复中,格局变化的研究将对矿区生态系统的变化起着至关重要的作用。其中,农业用地格局演变的过程及覆被类型的变化,对矿区的生态安全、耕地保护及土地资源可持续利用具有重要的现实意义。该文以山西平朔矿区为例,基于GIS平台,在分析矿区土地动态变化的基础上,运用景观生态学理论与方法,对平朔矿区景观动态变化过程、特征及覆被类型的变化进行了研究,特别对矿区农用地的变化做了重要分析,结果表明大型露天矿区生态系统景观动态变化过程包括生态破坏过程的景观变化(土地挖损、土地压占、土地占用)和生态重建过程的景观变化(地貌重塑、土壤重构、植被重建);经过20年的人工控制的生态重建后,矿区土地利用空间格局由以旱地—疏林地格局演变为以林地—建设用地为主的重建生态格局;矿区生态重建已经改变了原脆弱生态系统的生态环境,其中农业用地增加了50%,但由于管理制度等原因,复垦的农用地目前大部分尚不能转换为耕地使用。

In restoring abandoned mining area, patterns change research is important to ecosystems change. Patterns succession process of agricultural land and land cover types change delivered important practical signification for farmland protection, sustainable use of land resource and ecological safety of mining ecosystems. A case study was conducted on mining area in Pingshuo, Shangxi province. Based on GIS platform and land use change analysis in mining area, using landscape ecology theory and method, landscape dynamic change process, characteristics and land cover types change were investigated. The analysis of agricultural land use change was emphasized. Results show that landscape change process of large opencast mine ecosystem can be divided as two phases. The first phase is landscape change in ecological damange, including land excavating, piling and occupying. The second phase is landscape change in ecological restoration, which includes the reconstruction of landforms, soil and vegetation. After 20 years of ecological reconstruction under human control, land use patterns has been transformed from dry land-woodland dominated patterns to woodland-construction land dominated patterns. Furthermore, ecological reconstruction has improved the ecological conditions of mining area and agricultural land, and agricultural land area has increased by 50%. But now it has not been used entirely for plantation because of some management system.