引用本文: | 王建军,沈吉,张路,范成新,李文朝,潘继征.云南滇池和抚仙湖沉积物-水界面营养盐通量及氧气对其的影响.湖泊科学,2010,22(5):640-648. DOI:10.18307/2010.0503 |
| WANG Jianjun,SHEN Ji,ZHANG Lu,FAN Chengxin,LI Wenchao,PAN Jizheng.Sediment-water nutrient fluxes and the effects of oxygen in Lake Dianchi and Lake Fux-iain, Yunnan Province. J. Lake Sci.2010,22(5):640-648. DOI:10.18307/2010.0503 |
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摘要: |
采用间隙水连续采集法考察滇池和抚仙湖沉积物-水界面营养盐通量, 并比较在氧气缺乏及氧气充足条件下界面的氮磷行为.结果表明, 滇池草海沉积物-水界面营养盐通量显著高于滇池湖心及抚仙湖.对云南滇池及抚仙湖沉积物进行好氧和厌氧处理对照比较, 结果显示, 好氧组上覆水pH显著大于厌氧组, 而间隙水pH在两处理组之间差异不显著;这可能与厌氧呼吸途径过程中产生酸性物质有关;而在两种处理条件下, 间隙水均处于厌氧状态.较好氧条件而言, 厌氧条件下间隙水磷和铵氮浓度的增加, 与有机质矿化增强有关;而间隙水磷还可能受FeOOH-P模型控制.由分子扩散模型计算获得的界面磷或者铵氮扩散通量均高于表观通量, 而且好氧条件下的扩散通量与表观通量之间的差异较厌氧条件下的大;这表明两种营养盐均存在释放潜力, 但这种潜力的发挥受氧气的影响.较好氧条件而言, 厌氧条件下使用分子扩散模型得到的界面营养盐扩散通量更接近于表观通量. |
关键词: 沉积物-水界面 氧气 氮磷通量 滇池 抚仙湖 |
DOI:10.18307/2010.0503 |
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基金项目:中国科学院知识创新工程重大项目(KZCX1-YW-14);江苏省自然科学基金项目(BK2008055);归国人员基金(瞿文川)项目联合资助 |
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Sediment-water nutrient fluxes and the effects of oxygen in Lake Dianchi and Lake Fux-iain, Yunnan Province |
WANG Jianjun, SHEN Ji, ZHANG Lu, FAN Chengxin, LI Wenchao, PAN Jizheng
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State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, P. R. China
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Abstract: |
Continuous porewater extraction method was used to study the sediment-water nutrient fluxes and oxygen effects on the benthic nutrient fluxes in Lake Dianchi and Lake Fuxian. Overlying water pH of oxic sediment cores were significantly larger than those of corresponding anoxic ones, while there were no significant differences of porewater pH between the two conditions. It is most likely that the former was dominated by oxic mineralization and less acidic products were produced, while porewater was under anoxic condition and the anoxic mineralization was dominated under both conditions. Porewater species concentration (PO43- and NH4+ under the anoxic conditions was significantly lager than the oxic ones, which indicated an increasing of mineralization of organic matter under the former condition. It should be noted that the PO43- concentration in porewater was also related to FeOOH-Pmodel. Both phosphorus and ammonium fluxes calculated from the Fick's first law were all larger than the measured fluxes, which indicated that both nutrients had a potential to be released into the overlying water. However, it was interesting to find that the difference between the diffusive flux and measured flux under the oxic condition were greater than those under the anoxic condition. This implied that both fluxes were affected by oxygen, and the benthic nutrient fluxes could be better described by diffusive model under the anoxic condition than the oxic condition. |
Key words: Sediment-water interface oxygen nutrient flux Lake Dianchi Lake Fuxian |