渤海湾天津近岸海域沉积物氮赋存形态及其环境意义  

Nitrogen forms and their environmental significance in the sediments of Tianjin coastal waters, Bohai bay

作　　者：李清雪 梁秀莲 高亚茹 付超 赵海萍 孙健[3] LI Qing-xue;LIANG Xiu-lian;GAO Ya-ru;FU Chao;ZHAO Hai-ping;SUN Jian(School of Energy and Environmental Engineering,Hebei University of Engineering,Handan 056038,China;Architectural Design&Research Institute of Tsinghua University CO.,LTD.,Beijing 100084,China;State Key Laboratory of Hydroscience and Engineering,Tsinghua University,Beijing 100084,China)

机构地区：[1]河北工程大学能源与环境工程学院,河北邯郸056038 [2]清华大学建筑设计研究院有限公司,北京100084 [3]清华大学水沙科学与水利水电工程国家重点实验室,北京100084

出　　处：《海洋环境科学》2022年第3期378-386,共9页Marine Environmental Science

基　　金：国家重点研发计划项目(2016YFA0600901);国家自然科学基金项目(51779121);水沙科学与水利水电工程国家重点实验室科研课题项目(2020-KY-03)。

摘　　要：本研究采用连续分相浸取法,研究了渤海湾近岸海域沉积物中离子交换态氮(IEF-N)、碳酸盐结合态氮(CF-N)、铁锰氧化态氮(IMOF-N)及有机态和硫化物结合态氮(OSF-N)4种可转化态氮(TF-N)的含量及空间分布特征,进而揭示其环境意义。结果表明,表层沉积物中TF-N含量范围为145~233μg/g,均值为193μg/g,整体呈近岸高于远岸的空间分布特征,主要受陆源输入影响;各形态氮占总氮的比例为IEF-N(9.6%)> IMOF-N(4.4%)> OSF-N(3.9%)> CF-N(0.08%),空间分布各异。TF-N含量的垂向变化范围为24~313μg/g,不同站位垂向分布各异。TF-N中的IEF-N与IMOFN的含量随沉积深度增加呈增加的垂向分布特征,OSF-N在不同站位垂向分布各异,CF-N含量最小,其垂向变化不显著。根据沉积物质量评价指南,研究区域沉积物中的氮污染处于最低级别;各形态氮按结合能力完全释放后对上覆水的绝对贡献为IEF-N(44.4%)>OSF-N(35.4%)>IMOFN(19.7%)> CF-N(0.5%)。The concentrations and spatial distribution characteristics of the transferable nitrogen(TF-N)including ion-exchangeable form(IEF-N), carbonate form(CF-N), iron-manganese oxides form(IMOF-N) and organic matter-sulfide form(OSF-N) in the sediments of the coastal waters of Bohai bay were studied by the sequential extraction method, and further to reveal their environmental significance. The results showed that the concentrations of TF-N in the surface sediments ranged from 145 μg/g to 233 μg/g, with an average value of193 μg/g. Affected by terrestrial sources, the overall distribution characteristics of nearshore content were higher than far shore;the proportion of nitrogen forms in TN was: IEF-N(9.6%) > IMOF-N(4.4%) > OSF-N(3.9%) > CF-N(0.08%), and their spatial distribution was different. The vertical variation range of TF-N concentrations was 24 ~ 313 μg/g, and the vertical distribution varied in different research sites. IEF-N and IMOF-N in TF-N showed an increasing trend with increasing deposition depth, OSF-N had different vertical distributions at different stations, the concentrations of CF-N was the smallest, and its vertical change was not significant. According to the sediment quality assessment guidelines, TN in the sediments in the study area was at the lowest level;The absolute contributions of various forms of nitrogen after being completely released according to binding capacity to the overlying water were as follows: IEF-N(44.4%) > OSF-N(35.4%) >IMOF-N(19.7%) > CF-N(0.5%).

关 键 词：渤海湾 近岸海域 沉积物 氮形态 环境意义 

分 类 号：X132[环境科学与工程—环境科学] X55