Changing Biogeochemistry in the South China Sea

  • Chen-Tung Arthur ChenEmail author
  • Shujie Yu
  • Ting-Hsuan Huang
  • Hon-Kit Lui
  • Yan Bai
  • Xianqiang He
Part of the Atmosphere, Earth, Ocean & Space book series (AEONS)


The tropical/subtropical South China Sea (SCS) is the largest marginal sea in the world. Like other warm bodies of water, its sea surface temperature (SST) is rising, albeit more slowly (0.012 °C/yr between 1998 and 2016) than that of cold-water regions at high latitudes. The chlorophyll concentration increased at 0.0012 μg/L/yr during that period, and the Secchi disk depth (SDD) increased by 0.035 m/yr. The changes of SST, chlorophyll concentration and SDD, the factors governing changes in ocean biogeochemistry, in the SCS exhibit high temporal-spatial variability, and these parameters varied in opposite directions during the periods 1998–2008 and 2008–2016. The first period witnessed declining SST and SDD and increasing chlorophyll concentration, referring to enhancing primary productivity. The second period witnessed increasing SST and SDD but falling chlorophyll concentration, referring to declining primary productivity. These changes and increasing anthropogenic activities on land may be related to changing biogeochemistry such as decreasing dissolved oxygen concentration in coastal regions. In the SCS basin, however, particulate organic carbon and nitrogen seem to be on the rise.


South China Sea Sea surface temperature Salinity Chlorophyll Secchi disk depth pH Temporal changes 



Preparation of this chapter was supported by the Ministry of Science and Technology (MOST 107-2611-M-110-006 and 107-2611-M-110-021) and the Ministry of Education (Higher Education Sprout Program) of Republic of China. Two anonymous reviewers provided valuable comments which strengthened the manuscript.


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Copyright information

© Springer Nature Singapore Pte Ltd. 2020

Authors and Affiliations

  • Chen-Tung Arthur Chen
    • 1
    Email author
  • Shujie Yu
    • 2
  • Ting-Hsuan Huang
    • 1
  • Hon-Kit Lui
    • 1
  • Yan Bai
    • 2
  • Xianqiang He
    • 2
  1. 1.Department of OceanographyNational Sun Yat-Sen UniversityKaohsiungTaiwan
  2. 2.State Key Laboratory of Satellite Ocean Environment DynamicsSecond Institute of Oceanography, Ministry of Natural ResourcesHangzhouChina

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