赣江河水主离子化学特征和径流效应以及控制机制

Major ion chemical characteristics,runoff effect and controlling mechanism of Ganjiang River

赣江发源于我国中南部的江西省,是长江的一大支流,为了客观分析该河流的水化学特征,开展水质评价,对赣江1958~2016年水化学数据进行了收集和分析。结果表明:①Ca^2+,Na^++K^+,HCO3^-和SO4^2-是河流中的主要离子,pH值范围为6.0~8.8,TDS范围为15.7~141.0 mg/L,所有离子月变化量与河流流量呈正相关。1980年以前河流流量与SO4^2-,NO3^-和Cl^-的浓度月变化正相关程度高于1980年以后,这表明河水化学特征1980年之前主要是非点源成因,但1980年以后为多种来源的混合。②海盐源Cl^-占河水Cl^-的比例小于19%,硫酸参与硅酸盐岩和碳酸盐岩的风化,反映了1980年以后人为活动有所加强。Cl^-/(Na^++Cl^-)和SO4^2-/(Na^++Cl^-)的增加与江西省国内生产总量、人口、煤炭消耗、肥料用量的关系受废水排放影响。③根据世界卫生组织饮用水标准,赣江的水质符合饮用水标准,但应该警惕Cl^-和NO3^-浓度在1980年后在持续增加。

The Ganjiang River,originated from Jiangxi Province in southern China,is a tributary of the Yangtze River.In order to investigate the ion chemistry,runoff effects and controlling mechanisms of the Ganjiang River,its water chemistry data from 1958 to 2016 was collected and analyzed.The results were as follows:the major ions in the river were Ca^2+,Na^++K^+,HCO3^-♂and SO4^2-,the pH value was 6.0~8.8,the TDS range was 15.7~141 mg/L,and the monthly variation of all ion concentrations were positively correlated with river runoff.The positive correlations between river runoff and the monthly variation of SO4^2-,NO3^-♂and Cl^-before 1980 were higher than that after 1980,indicating that chemistry ion came from non-point sources pollution before 1980,but many sources appeared after 1980.The proportion of sea salt source Cl^-to river water Cl-was less than 19%,the sulfuric acid was involved in the weathering of silicate rock and carbonate rock,reflecting the strengthening of human activities after 1980.The increase of Cl^-/(Na^++Cl^-)and SO4^2-/(Na^++Cl^-)were related to the total domestic production,population,coal consumption,fertilizer utilization and waste water discharge.According to the World Health Organization standards,the water quality of the Ganjiang River can be used as drinking water.Nevertheless,continuous increase of Cl^-and NO3^-♂concentrations after 1980 should be payed attention to.