汉江中下游水华发展新形势及治理对策分析  

Analysis on status and countermeasures for bloom growth in middle and lower Hanjiang River

作　　者：陈峰 王文静 何涛 周浩然 钱宝 CHEN Feng;WANG Wenjing;HE Tao;ZHOU Haoran;QIAN Bao(Bureau of Hydrology,Changjiang Water Resources Commission,Wuhan 430010,China)

机构地区：[1]长江水利委员会水文局,湖北武汉430010

出　　处：《人民长江》2023年第10期7-17,共11页Yangtze River

基　　金：中科院A类先导科技专项“美丽中国生态文明建设科技工程”(XDA23040103)。

摘　　要：随着汉江沿岸经济社会的快速发展以及梯级水利枢纽的相继建成运行,汉江水环境和水动力条件也发生了较大变化,汉江中下游“水华”暴发频率不断增加,给区域水安全保障带来严峻挑战。2022年夏季,在长江流域“汛期反枯”的极端水文条件下,汉江中下游首次发现了蓝藻水华。依托长江流域水质监测中心现有监测站网及时开展了水华应急监测,对监测资料进行了综合分析,结合以往研究成果,初步分析2022年夏季水华成因,提出相应对策及建议。结果表明:①流域水体高营养盐水平仍是本次夏季水华发生的前提条件,高温、强辐射、高pH值是诱发因子,河道水量偏少是外部驱动条件。②汉江水华的时空分布和影响范围有扩大趋势,水体富营养化程度有加重趋势;加强水工程联合运用,改善水动力条件,调节环境容量,是缓减汉江中下游水华问题的最直接途径。③提出了优化综合站网布局、强化全要素动态监测、加强水华基础研究、建立水华防控协同机制等对策建议。With the rapid economic and social development along the Hanjiang River and the operation of cascade water conservancy projects,the water environment quality and hydrodynamic conditions of the Hanjiang River have undergone great changes.The water bloom in the middle and lower reaches of the Hanjiang River breaks out frequently,severely challenging regional water security.In the summer of 2022,cyanobacterial blooms were discovered for the first time in the middle and lower reaches of the Hanjiang River under the extreme hydrological conditions of"unusual drought during the flood season"in the Yangtze River Basin.Based on the existing monitoring station network of the Changjiang River Basin Water Quality Monitoring Center,emergency monitoring of water blooms was carried out in a timely manner,and comprehensive analysis on monitoring data was conducted.The results indicate that:①High nutrient levels in the watershed water bodies were still the prerequisite for the occurrence of water blooms in summer of 2022,with high temperature,strong radiation,and high pH values as inducing factors,and a small amount of river streamflow as an external driving factor.②The spatiotemporal distribution and impact range of water blooms in the Hanjiang River are expanding,and the degree of eutrophication in the water body is detertiatating.Strengthening the joint use of water engineering,improving hydrodynamic conditions,and regulating environmental capacity are the most direct ways to alleviate the water blooms in the middle and lower reaches of the Hanjiang River.③Suggestions are proposed including optimizing the layout of the comprehensive station network,strengthening dynamic monitoring of all factors,improving basic research on water blooms,and establishing a collaborative mechanism for water bloom prevention and control.

关 键 词：蓝藻水华 水动力条件 营养盐 水华预警 汉江中下游 2022年长江流域干旱 

分 类 号：X824[环境科学与工程—环境工程]