摘要
为分析长江中下游氮、磷、硅等营养盐的输送特征及洞庭湖、汉江、鄱阳湖对干流营养盐输送的贡献,于2020年9月自三峡坝前至河口及洞庭湖、汉江、鄱阳湖长江入汇口沿程采集水样,测定氮、磷、硅等营养盐浓度并分析沿程变化趋势,计算总氮、总磷和溶解硅通量及主要支流贡献。结果表明:长江中下游总氮浓度沿程下降,在1.23~2.32 mg/L间波动,溶解态占比超过95%;总磷浓度沿程上升,在0.01~0.08 mg/L间波动,以颗粒态为主;溶解硅浓度在汉口断面突增,三峡坝前-汉口江段均值为5.52 mg/L,汉口-河口江段均值升高为10.8 mg/L。总氮、总磷、溶解硅通量均沿程明显上升。洞庭湖、汉江及鄱阳湖对干流营养盐输送贡献较大,其中洞庭湖对总氮、总磷、溶解硅输送通量的贡献分别达到163.2%、67.9%、23.6%,但其汇入后干流水质类别未发生明显变化。洞庭湖、汉江及鄱阳湖汇入后干流水体综合营养状态指数波动范围在-12.72%至7.85%。本研究有助于了解长江中下游营养状态及支流湖泊对干流的贡献,为中下游水环境管理提供科学依据。
In order to analyze the transmission characteristics of nitrogen,phosphorus and silicon in the middle and lower reaches of the Yangtze river and the contribution of the Dongting Lake,Han River and Poyang Lake to the main stream,water samples were collected from the front of the Three Gorges dam to the estuary along the main stream and the entrances to the Yangtze River of the Dongting Lake,Han River and Poyang Lake in September 2020.Concentrations of nitrogen,phosphorus,silicon were measured,the variation trend of nutrient along the river was analyzed,nutrient flux and contribution of main tributaries were calculated.The results show that the total nitrogen concentration in the middle and lower reaches of the Yangtze River decreases along the river and fluctuates between 1.23 mg/L and 2.32 mg/L,and the proportion of dissolved nitrogen is more than 95%.The concentration of total phosphorus increases along the course and fluctuates between 0.01-0.08 mg/L,mainly in granular form.The dissolved silicon concentration increases sharply at the Hankou section,and the mean value from the front of the Three Gorges Dam to Hankou section is 5.52 mg/L,and the mean value from the Hankou section to estuary is 10.8 mg/L.Fluxes of total nitrogen,total phosphorus and dissolved silicon all increase obviously along the river.The tributary river and lakes contributes a lot to the transport of nutrients in the main stream,among which Dongting Lake contributed the most,contributing 163.2%,67.9%and 23.6%to the transport fluxes of total nitrogen,total phosphorus and dissolved silicon respectively,but the water quality of the main stream does not change obviously after Dongting Lake enters.The comprehensive trophic level index fluctuates between-12.72%and 7.85%after the Dongting Lake,Han River and Poyang Lake merge into the main stream.This study is helpful to understand the nutrient status of the middle and lower reaches of the Yangtze River and the contribution of the tributary river and lakes to the main stream,and to provide scientific
作者
俞洋
王丹阳
汤显强
黎睿
YU Yang;WANG Dan-yang;TANG Xian-qiang;LI Rui(Basin Water Environment Department,Yangtze River Scientific Research Institute,Wuhan 430010,China;Hubei Provincial Key Lab of Basin Water Resource and Eco-environmental Science,Yangtze River Scientific Research Institute,Wuhan 430010,China;China Three Gorges Corporation,Eco-Environmental Engineering Research Center,Beijing 100038,China)
出处
《长江流域资源与环境》
CAS
CSSCI
CSCD
北大核心
2022年第5期1039-1050,共12页
Resources and Environment in the Yangtze Basin
基金
中央级公益性科研院所基本科研业务费项目(CKSF2021531/SH
CKSF2021444/SH)
国家高层次人才特殊支持计划项目(CKSD2019542/SH)
中国长江三峡集团有限公司项目(201903145)。
关键词
长江中下游
营养盐
通量
洞庭湖
汉江
鄱阳湖
the middle and lower reaches of the Yangtze River
nutrient
flux
Dongting Lake
Han River
Poyang Lake
