摘要
长江口入海总磷通量对近海水域水环境、水生态具有重要影响,在优选入江控制断面的基础上研究了1999~2022年长江口水域总磷浓度和入海总磷通量。结果表明:①1999年以来入海总磷通量年际间波动较大,最大年通量是最小年通量的6.3倍。颗粒态磷通量波动大于溶解态磷通量。②长江口水域总磷浓度和入海通量总体皆呈先升后降的趋势,趋势转折点在2010年,该年度入海控制断面总磷年均浓度高达0.470 mg/L,入海总磷通量高达45.57万t/a。2008~2012年入海总磷通量相对较高,平均为29.05万t/a,至2018~2022年下降为14.33万t/a,长江流域总磷污染控制成效显著。③2010年以来,入海总磷通量和颗粒态磷通量及其占比皆呈显著下降趋势,颗粒态磷通量占比由2010年的90%下降为2022年的43%。④长江口水域总磷浓度枯水期高于丰水期,入海总磷通量丰水期高于枯水期。⑤2018~2022年来自长江上游、洞庭湖、汉江和鄱阳湖的磷源分别占30.5%,12.0%,4.5%和5.9%,其他来源的磷占47.1%。
The total phosphorus(TP)flux from the Changjiang River Estuary into the sea significantly affects the water environment and aquatic ecology of the nearshore areas.Based on an optimized control section at the river–sea interface,TP concentrations in the estuary waters and TP flux into the sea from 1999 to 2022 were investigated.The results showed that:①Since 1999,the annual TP flux into the sea has exhibited substantial interannual fluctuations,with the maximum annual flux being 6.3 times of the minimum.Particulate phosphorus flux varied more markedly than dissolved phosphorus flux.②TP concentration and flux generally followed a pattern of first increasing and then decreasing.The turning point occurred in 2010,when the annual average TP concentration at the control section reached 0.470 mg/L,and the TP flux into the sea peaked at 455,700 tons.Between 2008 and 2012,TP flux into the sea remained relatively high,averaging 290,500 tons per year.From 2018 to 2022,it declined to an average of 143,300 tons per year,indicating significant effectiveness of phosphorus pollution control in the Changjiang River Basin.③Since 2010,both the TP flux and particulate phosphorus flux into the sea,as well as their relative proportions,have shown a pronounced decreasing trend.The proportion of particulate phosphorus dropped from 90% in 2010 to 43% in 2022.④TP concentrations in the Changjiang River Estuary are higher in the dry season than in the wet season,whereas TP flux into the sea is greater in the wet season than in the dry season.⑤From 2018 to 2022,phosphorus contributions from the upper reaches of the Yangtze River,Dongting Lake,Hanjiang River,and Poyang Lake accounted for 30.5%,12.0%,4.5%,and 5.9%,respectively,while other sources contributed 44.0%.
作者
娄保锋
翟婉盈
王哲
周珂
黄志辉
王英才
LOU Baofeng;ZHAI Wanying;WANG Zhe;ZHOU Ke;HUANG Zhihui;WANG Yingcai(Monitoring and Scientific Research Center of Yangtze River Ecology and Environment Administration of MEE,Wuhan 430010,China;Hubei Key Laboratory of Intelligent Basin Aquatic Ecology Monitoring,Early-warning and Protection,Wuhan 430010,China;Lushui River Test Hub Management Bureau,Changjiang Water Resources Commission,Xianning 437300,China)
出处
《人民长江》
北大核心
2025年第12期18-27,共10页
Yangtze River
基金
国家重点研发计划课题(2021YFC3201002)
陆水水库除险加固工程环境保护监测及竣工验收技术服务(JG/2024/HBJC-01)
三峡工程生态与环境监测项目(JJ[2015-008],JJ[2015-047],JJ[2016-012])。
关键词
总磷
颗粒态磷
溶解态磷
磷来源
入海总磷通量
长江口
total phosphorus
particulate phosphorus
dissolved phosphorus
phosphorus source
total phosphorus flux into the sea
Changjiang River Estuary
