Diatoms modify the relationship between dissolved silicon and bicarbonate in the impounded rivers

  • Baoli Wang | baoliwang@163.com Chinese Academy of Sciences, China.
  • Cong-Qiang Liu Chinese Academy of Sciences, China.
  • Fushun Wang Shanghai University, China.
  • Benjamin Chetelat Chinese Academy of Sciences, China.
  • Stephen C. Maberly Lancaster Environment Centre, United Kingdom.

Abstract

In order to investigate the relationship between dissolved silicon (DSi) and bicarbonate (HCO3), we analysed water samples from the main Changjiang channel and its main tributaries in August 2006 and, during 2007-2009, the contrasting tributaries Wujiang (WJ) – mainly dominated by carbonate weathering, and Ganjiang – mainly dominated by silicate weathering. The DSi: HCO3 ratio ranged from 0 to 0.67, which is in agreement with mixing between the weathering of carbonate or silicate. A negative correlation between DSi and HCO3was observed and interpreted as the imprint of regional geology on water chemistry. This relationship and the DSi: HCO3 ratios illustrate the predominant role of carbonate weathering on the riverine HCO3, even forcatchments where silicate rocks are dominant. In contrast, a cascade of dams in WJ tributary influenced the concentrations of Dsi and HCO3 and resulted in a positive correlation between DSi and HCO3. This is because reservoirs allowed populations of diatomsto develop and diatoms stoichiometrically sequestered DSi and HCO3 causing a negative feedback regulation on the DSi: HCO3 ratio. Our study demonstrates that the relationship between DSi and HCO3can reflect not only their geological background but also the influence of algal activity (diatom uptake) within rivers.

Dimensions

Altmetric

PlumX Metrics

Downloads

Download data is not yet available.

Author Biographies

Baoli Wang, Chinese Academy of Sciences
State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry
Cong-Qiang Liu, Chinese Academy of Sciences
State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry
Fushun Wang, Shanghai University

Institute of Applied Radiation, School of Environmental and Chemical Engineering

Benjamin Chetelat, Chinese Academy of Sciences
State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry
Stephen C. Maberly, Lancaster Environment Centre

Centre for Ecology and Hydrology

Published
2013-10-08
Info
Issue
Section
Original Articles
Keywords:
chemical weathering, dam effect, diatoms, negative regulation, Changjiang river.
Statistics
  • Abstract views: 3468

  • PDF: 396
  • HTML: 837
How to Cite
1.
Wang B, Liu C-Q, Wang F, Chetelat B, Maberly SC. Diatoms modify the relationship between dissolved silicon and bicarbonate in the impounded rivers. J Limnol [Internet]. 2013Oct.8 [cited 2021May6];72(3):e40. Available from: https://jlimnol.it/index.php/jlimnol/article/view/jlimnol.2013.e40