【摘要】 选取湘江流域29个水质监测断面2008—2015年的水质监测数据,包括DO、COD_Mn、NH₃-N、TP、Pb、As、Cd,利用单因子评价法及季节性Mann-Kendall检验,对湘江流域的水质及其时空演化特征进行综合评价分析。结果表明:1)湘江流域水环境质量整体优良,且污染物浓度呈现持续下降趋势;部分地区受其自身条件及其发展的影响,污染类型及趋势差异明显。2)对于重金属Pb、As、Cd的整体治理效果要好于NH₃-N、TP。3)湘江流域内NH₃-N和TP的污染浓度表现为丰水期高于枯水期。而重金属污染差异明显,主要受河流流量变化以及历史排放的影响。4) 2008年以后,政府干预逐渐替代城市发展等经济因素成为影响湘江流域水环境变化的主要因素。更多还原

【Abstract】 The water environment problem is a realistic problem that affects residents ’ lives and social and economic development. Water quality monitoring data of 29 water quality monitoring sections in Xiangjiang River Basin from 2008 to 2015 were selected,including DO,COD_Mn,NH₃-N,TP,Pb,As,Cd,and single factor index and seasonal Mann-Kendall test were applied to comprehensively evaluate and analyze the water quality and temporal and spatial evolution characteristics of Xiangjiang River Basin. The results showed that: 1) The overall quality of the water environment in the Xiangjiang River Basin was excellent,and the concentration of pollutants continued to decline. In some areas,due to their own conditions and development pace,the types and trends of pollution were significantly different. 2) The overall treatment effect of heavy metals Pb,As,Cd was better than NH₃-N,TP. 3) The pollution concentration of NH₃-N and TP in the Xiangjiang River Basin was higher than that of the dry season. The heavy metal pollution was obviously different,mainly affected by river flow changes and historical emission. 4) Since 2008,government intervention gradually replaced economic factors（ e.g. urban development）,as the main factors affecting the water environment change in the Xiangjiang River Basin.更多还原