煤矸石堆场Fe、Mn迁移累积效应研究

通过对贵州织金典型煤矿区矸石堆场周边地表水体及耕地进行调查与采样分析,探讨了煤矸石堆场Fe、Mn元素迁移对周边地表水体及耕地累积效应的影响。研究结果表明:受煤矸石堆场酸性排水的影响,煤矸石堆场周边溪沟水Fe、Mn含量分别达0.81~32.14mg/L、1.17~8.42mg/L,超过"集中式生活饮用水地表水源地标准"限值的3~107、12~84倍。堆场周边旱作土中Fe、Mn含量分别达63 530~85 990mg/kg、243.1~910.1mg/kg,水稻土达46 940~75 810mg/kg、144.5~409.1mg/kg,Fe、Mn累积指数旱作土分别达1.61、2.97,水稻土分别达1.24、1.33。随着与堆场距离的增大,水稻土Fe、Mn含量逐步降低,在500m范围内Fe降低了35%,Mn降低了61%,而旱作土变化规律不明显。

Cumulative Effects Assessment of Fe and Mn's Migration in Gangue Yard of a Cultivated Land

Impacts of Fe and Mn''s migration in gangue yard of a cultivated land and their surface water in Zhijin County, Guizhou Province, China were studied. The soil and the water qualities were also evaluated. Results show that affected by the migration of acid mine drainage, contents of Fe and Mn in stream water of the gangue yard were 0.81 to 32.14 mg/L and 1.17 to 8.42 mg/L, 3 to 107 times and 12 to 84 times of the limited value of surface water source standard for centralized drinking of China, respectively. Contents of Fe and Mn were 63 530 to 85 990 mg/kg, and 243.1 to 910.1 mg/kg in dry land and 46 940 to 75 810 mg/kg and 144.5 to 409.1 mg/kg in the paddy soil of the gangue yard, respectively. The comprehensive accumulative index of Fe and Mn were 1.61 and 2.97 in dry land, and 1.24 and 1.33 in the paddy soil, respectively. The contents of Fe and Mn in paddy soil asymptotically decrease with increasing distance from the gangue yard. There were 35% decrease of Fe and 61% decrease of Mn in the range of 500 meters in paddy soil, while no obvious decreasing or increasing clues in dry land.