A Massive Green Tide in the Yellow Sea in 2021: Field Investigation and Analysis

Int J Environ Res Public Health. 2022 Sep 17;19(18):11753. doi: 10.3390/ijerph191811753.

Abstract

A massive green tide occurred in the Southern Yellow Sea (SYS) in 2021. As in previous years, its high biomass caused trouble to the coastal environment and landscape in 2021. Unusually, the 2021 green tide was unexpectedly massive. Thus, field surveys and remote sensing were conducted in the SYS from December 2020 to July 2021. Compared to pure satellite observations, it revealed the initial development of the green tide more clearly. Given the effects of temperature and nutrient changes on green tide biomass, we compared the environmental parameters in recent years and found no significant increase in nutrient concentrations or changes in temperature of the SYS in 2021. Relative to 2020, the 2021 green tide exhibited a wide distribution, high biomass, and prolonged duration. It was mainly affected by (1) reduced implementation of source-control measures and (2) limited Sargassum biomass, which reduced competition for Ulva prolifera. Strengthening the implementation of source control measures in Subei Shoal is recommended, which is currently the most effective way to control green tides.

Keywords: Yellow Sea; causes; development; green tide.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Biomass
  • China
  • Eutrophication
  • Sargassum*
  • Temperature
  • Ulva*

Grants and funding

This research was funded by the Science & Technology Basic Resources Investigation Program of China, grant number 2018FY100200, the Strategic Priority Research Program of the Chinese Academy of Sciences, grant number XDA23050302, Key Deployment Project of Centre for Ocean Mega-Research of Science, Chinese Academy of Science, grant number COMS2019Q05, and the Sino-Australian Centre for Healthy Coasts, grant number 2016YFE0101500.