| 摘要: |
| 太湖作为一个大型富营养化湖泊，不同湖区沉积物内源污染及释放特征差异显著。以太湖草型湖区胥湖和藻型湖区竺山湖为研究对象，研究分析不同水深下草/藻型湖区底泥内源污染和氮磷扩散通量变化规律。结果表明，胥湖和竺山湖沉积物中总氮含量分别为2.59~3.33g·kg-1和2.95~3.63g·kg-1，总磷含量分别为0.462~0.652g·kg-1和0.749~0.916g·kg-1。藻型湖区沉积物中营养盐含量显著高于草型湖区，且含量均随水深变化呈不规律波动。沉积物磷形态分析表明，胥湖沉积物中以钙磷为主，且钙磷在总磷中的占比随水深增加而明显下降，竺山湖沉积物中磷形态以铁磷为主，铁磷、铝磷和钙磷在总磷中的占比随水深增加逐步上升。胥湖浅水区域沉积物-水界面SRP含量明显高于深水区域，Fe2+和NH4+浓度在不同水深下差别较小，竺山湖浅水区域沉积物-水界面SRP、Fe2+和NH4+含量均高于深水区域。胥湖和竺山湖内源释放风险均较小，胥湖NH4+扩散通量总体随水深增加而先下降后上升，竺山湖NH4+扩散通量随水深增加而明显升高。研究结果对于深入理解水深对太湖草/藻型湖区沉积物-水界面氮磷迁移规律具有重要作用。 |
| 关键词: 草/藻型湖区 沉积物 水深 内源污染 扩散通量 |
| DOI： |
| 分类号: |
| 基金项目:水利部重大科技项目 |
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| Depth-related sediment pollution characteristics and release fluxes in phytoplankton- and macrophyte-dominated areas of Lake Taihu |
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Zong Yuqing,Li Hui,Wu Donghao,Shi YaDong,Yuan Lin,Guo Qingchun,Zou Yue,Sheng Huiwen
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Taihu Basin Monitoring Center of Hydrology and Water Resources
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| Abstract: |
| Lake Taihu is a large eutrophication lake, the endogenous pollution and release characteristics of sediments in different lake areas were significantly different. The study investigated and analyzed the variation of endogenous pollution and nitrogen and phosphorus diffusion fluxes in Xuhu (grass-dominated zone) and Zhushan Bay(algae-dominated zone) with different water depths. The results showed that: The total nitrogen content in the sediments of Xuhu Lake and Zhushan Lake was 2.59~3.33g·kg-1 and 2.95~3.63g·kg-1, and the total phosphorus content was 0.462~0.652g·kg-1 and 0.749~0.916g·kg-1, respectively. The nutrient content in the sediments of the algae lake area was significantly higher than that in the grass lake area, and the content fluctuated irregularly with the change of water depth. Phosphorus speciation analysis of sediments showed that: Ca-P were the main sediments in Xuhu Bay, and the proportion of Ca-P in total phosphorus decreased significantly with the increase of water depth.The phosphorus morphology in the sediments of Zhushan Lake was dominated by Fe-P, and the proportions of Fe-P, Al-P and Ca-P in the total phosphorus gradually increased with the increase of water depth. The SRP content at the sediment-water interface in the shallow water area of Xuhu is significantly higher than that in the deep water area, while the difference in Fe2+ and NH4+ concentrations between different water depths is relatively small. The SRP, Fe2+ and NH4+ contents at the sediment-water interface in the shallow water area of Zhu Mountain Lake are all higher than those in the deep water area.The endogenous release risk of Xuhu and Zhushan Lake was small, and the NH4+ diffusion flux of Xuhu Lake decreased first and then increased with the increase of water depth, and the NH4+ diffusion flux of Zhushan Lake increased significantly with the increase of water depth. The results play an important role in understanding the nitrogen and phosphorus migration of water depth at the sediment-water interface in the grass/algae lake area of Taihu Lake. |
| Key words: Grass/algal lake area sediments water depth endogenous pollution diffusion flux |
