摘要
为探究崇明岛河网水污染时空分布规律,助力世界级生态岛建设,依据崇明岛779个实测断面水质数据,采用污染物平衡结合河网水动力水质模型的单因子评价方法,进行了污染时空深度分析。结果表明:崇明岛河网水质达标率为69.2%,污染强度较高的地区与粮食产区、城桥镇等中心城区高度吻合,其余地区污染分布分散均匀且遍及全岛;崇明岛河网水质月际差异明显,4月~10月超标水体占比51.69%~96.27%,11月~3月超标水体占比27.08%~44.46%;种植业是崇明岛河网污染的主要来源,冗余的氮、磷元素沉积和吸附在土壤中,夏秋季伴随农田漫灌及强降雨进入河网;污染物主要囤积于支级河道中,骨干河道水量占比46%,纳污量占比28%,支级河道水量占比54%,纳污量占比72%;引排水能起到一定的削减作用,河网自净降解量大于引排水削减量;可通过净化支级流域末端尾水、提升支级河道流动性、开展高污染片区集中治理、加大引排能力及频次等针对性措施有效改善污染程度。
To investigate the spatial and temporal distribution patterns of water pollution in the river network of Chongming Island and support the construction of a world-class ecological island,a single factor evaluation method combining pollutant balance with river network hydrodynamic water quality model is used to conduct a deep pollution spatiotemporal analysis based on water quality data from 779 measured sections of Chongming Island.The results show that,(a)the ratio up to water quality standards in Chongming Island is 69.2%,the areas with high pollution intensity are highly consistent with grain producing areas and central urban areas such as Chengqiao Town,while other areas are evenly distributed and spread throughout the island;(b)the water quality of river network in Chongming Island varies significantly between months,and the proportion of water exceeding the standard from April to October is 51.69%-96.27%and that from November to March is 27.08%-44.46%;(c)the planting pollution is the primary pollution source of Chongming Island,and excess nitrogen and phosphorus in fertilizer are deposited and adsorbed in the soil and are washed into the river network by farmland flooding and heavy rainfall in summer and autumn;(d)the pollutants are mainly stored in branch rivers,and the amount of pollution in main channels takes up 28%of total pollutants with 46%of total water volume,and in branch rivers,there are 72%and 54%,respectively;(e)the water diversion and drainage can play a certain role in pollution reduction,but the purification of river network itself is better;and(f)the pollution level can be effectively improved through targeted measures such as purifying the tail water at the end of branch river basin,improving the liquidity of branch river,carrying out centralized treatment of highly polluted areas and increasing the capacity and frequency of water diversion and drainage.
作者
刘宏宽
赵庚润
滕飞
LIU Hongkuan;ZHAO Gengrun;TENG Fei(Planning and Research Institute,Shanghai Water Engineering Design and Research Institute Co.,Ltd.,Shanghai 200061,China;Shanghai Engineering Research Center of Coastal Zones,Shanghai 200061,China)
出处
《水力发电》
CAS
2023年第10期17-21,50,共6页
Water Power
基金
上海市科学技术委员会科研资助项目(22DZ1202700,20DZ1204400,19YF1444000)。
关键词
水污染
污染特征
污染防治
感潮河网
崇明岛
water pollution
pollution characteristics
pollution prevention
tidal river network
Chongming Island
