煤矸石场植被恢复初期生态绩效评价

Ecological performance assessment on early plant reclamation in coal gangue yard

以山西潞安矿业集团司马煤业有限公司煤矸石场生态恢复5年内(2009—2013年)的植被-土壤系统为研究对象,在固定监测样地调查的基础上,以空间变化代替时间变化,对煤矸石场人工种植乔木层条件下,草本植物自然恢复初期的生态绩效进行了评价,结果表明:1)相较于1a恢复期,煤矸石场植被恢复初期植物群落基本特征、土壤物理性质、土壤化学性质及其综合生态绩效在5a恢复期时均达到了"优"级水平;2)在足够长的恢复期内,人工种植乔木层条件下,草本植物的自然恢复可以实现矿区的植被重建;3)基于AHP-FCE评价模型,以1a恢复期为基准,通过各恢复期生态指标与1a恢复期相比的恢复程度设定绩效等级,对煤矸石场植被恢复初期的生态绩效进行评价,避免了以往选取天然次生群落为恢复目标,但又不确定其是否为最佳恢复效果的盲目性,为生态绩效评价提供了新思路。

This study monitored the five-year dynamics of the plant-soil system in the coal gangue yard at Sima Coal Mine of Lu＇an Group from 2009 to 2013. The fixed plots were established to use spatial dynamics to represent temporal changes. The assessment was made on the communities characteristics,soil physical and chemical properties,and the comprehensive ecological performance of the plant communities at the early phase of reclamation after reforestation. The results were as follows： 1） The evaluation criterion of ecological performance included five ranks： ＂Optimal＂,＂Fine＂,＂Middle ＂,＂Low＂,＂Lower＂at the early stage of restoration on coal waste pile. Referential to the first year,the five-year recovery achieved the ＂Optimal＂rank according to the communities characteristics,soil physical and chemical properties,and the comprehensive ecological functions in the reclaimed coal gangue yard. Notwithstanding the ecological performance of natural secondary community also showing the ＂Optimal ＂rank in this study,natural secondary community was not the perfect object for reforestation. This result predicted that the ecological performance of reforestation in coal gangue yard might be better than natural secondary community with recovery age. 2） Given sufficient time,the reforestation and the spontaneousherbal recovery would achieve the goal of vegetation reconstruction in the mining area. 3） By employing the AHP-FCE model,using the first-year as benchmark,the performance criteria could be made for ranking the ecological performance in the early phases of reclamation. This was advantageous over the traditional method that taken natural secondary communities as the reclamation goal,whose optimism was usually questionable for high uncertainty. In this regard,this study attempted to provide an innovative way in the practice of ecological performance assessment. Moreover,this paper would play an actively model-driven role in advancing the scientific implementation,management,and evaluation of the ecological restoration in the coal gangue yard.