丹江口水库氮磷时空分布特征及水质安全保障对策  

Features of spatial and temporal distribution of nitrogen and phosphorus in the Danjiangkou Reservoir and safeguarding measures for water quality

作　　者：余启辉 林莉[2] 金海洋 陈力 Yu Qihui;Lin Li;Jin Haiyang;Chen Li

机构地区：[1]长江水利委员会水资源节约与保护局,武汉430010 [2]长江科学院流域水环境研究所,武汉430010

出　　处：《中国水利》2024年第20期59-66,共8页China Water Resources

基　　金：国家自然科学基金面上项目(52179057);湖北省自然科学基金杰出青年项目(2023AFA056);中央级公益性科研院所基本科研业务费专项基金项目(CKSF2023337/SH)。

摘　　要：为加强丹江口水库及其上游流域水质安全保障,基于丹江口水库32个水质监测断面2017—2023年监测数据,分析丹江口水库水质及关键指标总氮和总磷的时空分布特征,核算水库氮磷的不同来源及贡献,评估水库富营养化及水华风险。结果表明:丹江口水库水质总体良好,以Ⅰ~Ⅱ类为主,总磷浓度基本保持稳定,总氮浓度波动上升;湖北库区总磷和总氮浓度高于河南库区,上游至下游呈降低趋势;2021年汛期出现持续强降雨,总磷和总氮浓度明显升高。入库河流水质稳定向好,Ⅰ~Ⅲ类占比逐渐上升,总磷和总氮浓度下降并趋于稳定;氮磷来源以上游流域污染输入为主,消落区淹没释放次之,沉积物释放影响较小;丹江口水库总体呈中营养状态,但部分水域在特定季节呈现富营养化,支流回水区和库湾水华时有发生,富营养化及水华风险不容忽视。建议加强库区上游流域污染源治理,严格消落区管理,提高水质监测预警能力,深化水质安全保障科学研究,加强体制机制建设。In order to safeguard water quality of the Danjiangkou Reservoir and its upstream watershed,features of spatial and temporal distribution and key indicators of total nitrogen and total phosphorus were analyzed based on monitoring data of 32 water quality monitoring sections of the Danjiangkou Reservoir from 2017 to 2023.Calculation and evaluation were conducted for different sources and contributions of nitrogen and phosphorus and risks of eutrophication and algal blooms in the reservoir.The results indicate that water quality of the Danjiangkou Reservoir is generally good,mainly classified as Class Ⅰ~Ⅱ,with stable total phosphorus concentration and fluctuating total nitrogen concentration.Total phosphorus and total nitrogen concentrations in the Hubei reservoir area are higher than those in the Henan reservoir area,with a decrease tendency from upstream to downstream.Continuous heavy rainfall occurred during the flood season in 2021,resulting in a significant increase in total phosphorus and total nitrogen concentrations.Water quality of the incoming river has been stable and improving,with the proportion of Class Ⅰ~Ⅲ gradually increasing,while the concentrations of total phosphorus and total nitrogen decrease and tend to stabilize.The main source of nitrogen and phosphorus comes from upstream watersheds,followed by inundation release from subsidence areas,but the influence of sediment release is relatively small.The Danjiangkou Reservoir is generally in a moderately nutritious state,but some water bodies exhibit eutrophication during specific seasons.Water blooms occur in the backwater areas of tributaries and reservoir bays,and the risks of eutrophication cannot be ignored.It is suggested to reinforce control of pollution sources in the upstream of the reservoir area and subsidence areas,enhance capability of water quality monitoring and early warning,scientific research on water quality safeguarding and perfection of institutional mechanisms.

关 键 词：丹江口水库 氮磷浓度 污染负荷 水质风险 富营养化 

分 类 号：TV213.4[水利工程—水文学及水资源]