神府榆矿区地表水化学特征及水环境质量评价

Hydro-chemical characteristics and quality assessment of surface water in Shen-Fu-Yu mining area

基于研究区地质、水文地质条件,结合水样检测结果,利用piper三线图、Gibbs图及数理统计等方法,研究了神府榆矿区主要地表水的水化学阴阳离子(K+、Na+、Ca^(2+)、Mg^(2+)、HCO_3^-、SO_4^(2-)、Cl^-)的特征及重金属元素(Pb、Cd、As、Mn、Cr^(6+))、有机物(CODCr、TOC、UV254)的空间分布特征,并采用单因子评价法和梅罗指数综合评价法评价水环境质量。结果表明研究区地表水水质类型总体上表现为低矿化度的HCO_3·SO_4-Ca·Na或HCO_3-Ca·Mg型水,但是窟野河的水质类型多以SO_4·HCO_3(Cl)-Na为主,矿化度最高可达1037.5mg/L。水化学成分不但受岩石风化、蒸发结晶等自然因素的影响,而且人类活动已经逐渐成为影响该区域地表水化学特征的主要因素,其中窟野河受人类活动的影响最大。全区重金属及有机物浓度相对较低,但是窟野河中的CODCr浓度远超过相关标准。神府榆矿区地表水水质总体较差,窟野河水质相对最差,其中窟野河污染主要由F-、TDS及CODCr超标引起,秃尾河、榆溪河和无定河污染主要由NO-3引起。

The Characteristics of major ions（ K^＋,Na^＋,Ca^2＋,Mg^2＋,HCO3^-,SO4^2-,and Cl^-）,heavy metals（ Pb,Cd,As,Mn,and Cr^6＋） and organics（ CODCr,TOC,and UV254） in surface water collected from Shen-Fu-Yu mining area were analyzed using the Piper diagram,Gibbs diagram and mathematical statistics. Then the single factor pollution evaluation method as well as Nemerow pollution index method were used to evaluate water quality. The results showed that the hydro-chemical type was HCO3-Ca·Mg or HCO3·SO4-Ca·Na with low salinity on a whole,but SO4·HCO3（ Cl）-Na in Kuye River was higher with salinity as much as1037. 5 mg/L. The major ions of surface water were not only influenced by carbonate weathering and evaporative crystallization,but also by human activities,and the human activities had gradually become one of the major ingredients. The concentrations of heavy metals and organics were generally low,but the concentrations of the CODCrin Kuye River was higher and far exceeded the related standards. The quality of surface water was not good from the whole point of view,while among them Kuye River is the worst; the pollution in Kuye River was resulted from F^-,TDS and CODCr but NO3^- in other rivers.