金华江城区段河流水化学变化及其控制因素

Changes in River Water Chemistry of the Urban Section of Jinhua River and Its’ Controlling Factors

为揭示金华江城区段河流水化学变化及其控制因素,从2015年8月到2016年6月对金华江城区段进行了连续11个月的采样分析,并结合当地降水等数据,得到以下结论：（1）金华江城区段河水p H值的变幅为6.80~7.70,呈现中性,电导率EC的变化范围较大,流域TDS含量低于世界河水平均值,流域阳离子以Ca^（2＋）为主,阴离子以HCO_3^-为主,河水水化学类型为HCO_3^--Ca^（2＋）型;（2）主要离子浓度具有明显的季节变化特征,总体上呈现出夏季低、冬季高的特点,Cl^-浓度变化与降水量变化具有一致性;（3）水化学控制因素以岩石风化为主,但也有向大气降水控制型过渡的趋势,人类活动对河流水化学也产生了很大影响。

In order to reveal the changes in river water chemistry of the urban section of Jinhua River and it’s controlling factors,we monitored river waters of the urban section of Jinhua River from August 2015 to June 2016.Combined with the local data of precipitation,we got the following conclusions：（1）p H of 6.80-7.70,shows the neutral,with a broader range of variation of the EC,and TDS content of the river below the world average;Ca^（2＋）and HCO_3^-are the major anions,so water chemistry type is HCO_3^--Ca^（2＋）;（2）trace elements ion concentrations show seasonal variation characteristics of low in summer and high in winter with consistent changes of Clconcentration and precipitation;（3）water chemistry controls the main factors in weathering of rocks,but there is a tendency to control the precipitation type transition;human activities also has a significant impact on river water chemistry.