Faculty of Engineering, Science, and Mathematics, SUNY Institute of Technology, 100 Seymour Road, Utica, NY 13502, USA.
Sci Total Environ. 2011 Feb 1;409(5):941-8. doi: 10.1016/j.scitotenv.2010.11.030. Epub 2010 Dec 16.
Abandoned mine land (AML) is one of the legacies of historic mining activities, causing a wide range of environmental problems worldwide. A stream monitoring study was conducted for a period of 7 years to evaluate the water quality trend in a Mid-Appalachian watershed, which was heavily impacted by past coal mining and subsequently reclaimed by reforestation and revegetation. GIS tools and multivariate statistical analyses were applied to characterize land cover, to assess temporal trends of the stream conditions, and to examine the linkages between water quality and land cover. In the entire watershed, 15.8% of the land was designated as AML reclaimed by reforestation (4.9%) and revegetation (10.8%). Statistic analysis revealed sub-watersheds with similar land cover (i.e. percentage of reclaimed AML) had similar water quality and all tested water quality variables were significantly related to land cover. Based on the assessment of water quality, acid mine drainage was still the dominant factor leading to the overall poor water quality (low pH, high sulfate and metals) in the watershed after reclamation was completed more than 20 years ago. Nevertheless, statistically significant improvement trends were observed for the mine drainage-related water quality variables (except pH) in the reclaimed AML watershed. The lack of pH improvement in the watershed might be related to metal precipitation and poor buffering capacity of the impacted streams. Furthermore, water quality improvement was more evident in the sub-watersheds which were heavily impacted by past mining activities and reclaimed by reforestation, indicating good reclamation practice had positive impact on water quality over time.
废弃矿区（AML）是历史采矿活动的遗留问题之一，在全球范围内造成了广泛的环境问题。本研究对一个阿巴拉契亚中部流域进行了为期 7 年的溪流监测，以评估过去煤炭开采对该流域的影响，并评估造林和植被恢复后水质的变化趋势。本研究采用 GIS 工具和多元统计分析来描述土地覆盖，评估溪流状况的时间趋势，并研究水质与土地覆盖之间的关系。在整个流域，15.8%的土地被指定为经过造林（4.9%）和植被恢复（10.8%）的废弃矿区。统计分析表明，具有相似土地覆盖（即已开垦废弃矿区的百分比）的子流域具有相似的水质，所有测试的水质变量均与土地覆盖显著相关。基于水质评估，尽管在过去 20 多年前完成了矿区复垦，但酸性矿山排水仍然是导致流域整体水质较差（低 pH 值、高硫酸盐和金属含量）的主要因素。然而，在已开垦的废弃矿区流域中，与矿山排水相关的水质变量（pH 值除外）呈现出显著的改善趋势。流域中 pH 值没有得到改善可能与金属沉淀和受影响溪流的缓冲能力差有关。此外，在过去采矿活动影响严重且经过造林恢复的子流域中，水质改善更为明显，表明随着时间的推移，良好的复垦实践对水质产生了积极影响。
