在线客服: 点击这里给我发消息  新用户使用步骤:会员注册→充值→重新登入→进入资源
标题:Nitrogen exchange across the sediment-water interface after dredging: The influence of contaminated riverine suspended particulate matter.
时间:2020-01-15 16:54:38
DOI:10.1016/j.envpol.2017.07.054
PMID:28774552
作者:Liu, Cheng; Chen, Kaining; Wang, Zhaode
出版源: 《Environmental Pollution》 :S0269749116325374
摘要:Dredging has been widely implemented in shallow lakes to reduce internal nitrogen (N) loading. The suspended particulate matter (SPM) coming from polluted rivers usually contains high levels of N and ultimately deposits on the dredged sediment surfaces near the river mouth. To study the influence of the riverine SPM on N exchange across the sediment-water interface (SWI) after dredging, a 360-day experiment was carried out comparing un-dredged and dredged sediments from Lake Chaohu, China. Dredged treatments showed a significant increase ( p <0.01) in total N concentrations in the sediments, while the deposition of SPM had little influence on labile NH 4 + -N concentrations. In addition, NH 4 + -N concentrations in pore-water and NH 4 + -N fluxes were significantly lower in dredged than in un-dredged sediments, despite the deposition of SPM. The oxygen production rates and the oxygen penetration depth in the dredged sediments were both higher than those in the un-dredged sediments. The increase of Nitrospira in dredged sediments was consistent with their decreased NH 4 + -N concentrations and fluxes across the SWI. Therefore, the oxidizing condition, increased oxygen production/consumption rates and Nitrospira relative abundance across the SWI were believed to be correlated with the low N exchange rates in dredged sediments. Dredging for reducing internal N loading in a river mouth area is therefore feasible, although the influence of the riverine SPM should be taken into account when aiming to achieve a long-term internal N loading reduction.
大小:1790 kb
下载: 点击下载
预览:

浏览器不支持嵌入PDF阅读,打开新页面在线阅读

目录:
  • Nitrogen exchange across the sediment-water interface after dredging: The influence of contaminated riverine suspended part ...
    • 1. Introduction
    • 2. Materials and methods
      • 2.1. Field sampling
      • 2.2. Experimental design
      • 2.3. Chemical and microbial analysis
      • 2.4. Statistical analysis
    • 3. Results and discussion
      • 3.1. Variations on nitrogen concentrations and fractions in the sediment
      • 3.2. Oxygen production/consumption across the SWI
      • 3.3. NH4+-N profiles in pore-water
      • 3.4. Nitrogen exchange across the SWI
      • 3.5. Variations in sediment bacterial community
      • 3.6. Influence of SPM on nitrogen exchange
    • 4. Conclusions
    • Acknowledgements
    • Appendix A. Supplementary data
    • References

本页内容由网络收集而来,版权归原创者所有,如有侵权请及时联系