【摘要】 以兰州市45组浅层地下水样品水化学组分测试结果为依据,研究兰州市地下水中铁、锰分布特征。结果表明:兰州市浅层地下水中铁、锰含量总体较高,局部区域超标严重。对比1994年颁布的地下水质量标准,地下水中铁、锰超标率分别为62. 1%和55. 2%。研究区浅层地下水中铁、锰含量空间分布特征基本一致,受黄河淡水补给,黄河沿岸傍河地带地下水水质较好,地下水中铁锰含量较低。其余大部分区域地下水水质较差,城关区、七里河区、西固区、安宁区均存在地下水中铁、锰含量超标现象,且超标区域分布较广。研究区地下水中铁、锰含量超标主要是受原生沉积环境所致,而局部河谷地区浅层水铁、锰含量超标则主要受人为污染所致。地下水中Fe、Mn离子的迁移和富集,除了与含水介质成分、上覆土层性质、酸碱条件、地下水径流条件、"盐效应"有关外,主要受控于氧化还原环境。更多还原

【Abstract】 45 shallow groundwater samples were collected from Lanzhou city and analyzed for their chemical composition,and the distribution and source of Fe and Mn in groundwater in Lanzhou city were studied. Generally,the shallow groundwater in Lanzhou city is significantly polluted by Fe and Mn,and they have exceeded the groundwater standard the rates by 62. 1% and 55. 2% for Fe and Mn in groundwater samples,respectively. The spatial distribution characteristics of iron and manganese in the shallow groundwater are basically the same. The iron and manganese contents in groundwater ware lower in the riverside area. Groundwater samples are polluted the most in Chengguan district,Qilihe District,Xigu District,and Anning District. The excessive contents of iron and manganese in groundwater are mainly caused by the primary sedimentary environment. The excessive Fe and Mn elements in shallow groundwater are mainly caused by human pollution. The migration and enrichment of Fe and Mn ions in groundwater are mainly controlled by oxidation-reduction environment besides water medium composition,soil properties,acid-base conditions,groundwater runoff conditions and salt effect.更多还原