生态恢复年限对大宝山矿山排土场土壤环境质量演变的影响

Influence of ecological restoration years on soil environmental quality evolution of Dabaoshan mine waste dump

随着矿业开采的活动日益频繁,矿山废弃地产生的环境问题逐渐严重,因此矿山废弃地的生态修复工作逐渐受到大家的关注。本研究以韶关大宝山地区矿山排土场为研究对象,将采用“化学基质改良+植被修复模式”进行生态修复工作的区域进行对比,通过调查植被多样性,比较土壤水稳定性团聚体含量以及各项理化指标的变化,评价不同修复年限后工作的长效性。结果表明:矿区修复三年后,土壤重量直径和土壤几何平均直径增加到1.3147mm、1.5847mm和0.6250mm、0.6800mm,土壤pH值提升到4.66、5.00,土壤总钾、总氮、总磷分别增加到0.4563 g·kg^(-1)、0.4868 g·kg^(-1),0.16432 g·kg^(-1)、0.1163 g·kg^(-1),12.4744 g·kg^(-1)、13.9027 g·kg^(-1),但修复五年后,这些指标却出现了不同程度的下降,这说明化学基质改良+植物修复的模式能改善大宝山矿区排土场状况,但长效性不足。

With the increasing frequency of mining activities, the environmental problems of mine wasteland are gradually serious, so the ecological restoration of mine wasteland has gradually received attention from everyone. The mine dump related areas in Dabaoshan area of Shaoguan being taken as the research object will be compared after five consecutive years chemical modified matrix with phytoremediation. In order to evaluate the long-term effect of ecological restoration, the diversity of vegetation and the change of content of soil water aggregate and physical and chemical indexes will be analysed.The results showed : Three years after the mining area was restored, the MWD and GMD of soil increased to 1.3147 mm,1.5847 mm, 0.6250 mm and 0.6800 mm, while soil pH increased to 4.66 and 5.00, soil total potassium, total nitrogen and total phosphorus increased to 0.4563 g·kg^(-1), 0.4868 g·kg^(-1), 0.16432 g·kg^(-1), 0.1163 g·kg^(-1), 12.4744 g·kg^(-1)and 13.9027g·kg^(-1), respectively. However, these indexes declined to different degrees after five years of restoration, which indicated that the mode of chemical matrix improvement + phytoremediation can improve the situation of the dump in Dabaoshan Mining area and its long-term performance is insufficient.