Study reveals nonlocal population sources triggering dinoflagellate blooms in Changjiang Estuary and adjacent seas

algal
Credit: Pixabay/CC0 Public Domain

The Changjiang Estuary and adjacent sea area suffer from frequent harmful algal blooms, exerting impacts on ecological environment and fishery resources. 

About 60 percent of are caused by dinoflagellates. However, the population source of some dinoflagellates in this area remains unknown. 

Researchers led by Prof. Yin Baoshu and Prof. Yu Rencheng from the Institute of Oceanology of the Chinese Academy of Sciences (IOCAS) explored the possible nonlocal population sources to the Changjiang Estuary and adjacent seas. 

The study was published in JGR-biogeosciences.

The Changjiang River runoff, the Taiwan Warm Current and the Kuroshio Current are important sources of nutrient input in the Changjiang Estuary and adjacent seas. 

Researchers revealed that the Kuroshio Current provides not only nutrients, but also initial populations for harmful algal blooms. Although the nutrient input from the Taiwan Warm Current has little contribution to the harmful algal blooms, it can also serve as a population source for the dinoflagellate blooms in this area. 

The research team constructed a coupled physical-biological model suitable for East China Sea, and combined an adjoint model with the coupled model for the first time. The simulated results revealed that dinoflagellate populations in the Taiwan Strait and eastern Taiwan are nonlocal cell sources of dinoflagellate blooms in the study area in May. The appearance time of the initial population in two non-local source areas affected the dinoflagellate biomass and bloom range in the study area. 

The dinoflagellates biomass in the study area decreased significantly with the decrease of the initial population density in the Taiwan Strait, while it still maintained a high value when the initial population density decreased in eastern Taiwan. In other words, even a small initial  of dinoflagellate in eastern Taiwan could trigger a large-scale in the Changjiang Estuary and adjacent seas. 

This new discovery not only offers a new strategy to the prediction of algal blooms in the Changjiang Estuary and adjacent sea area, but also provides target domains for finding nonlocal dinoflagellate cysts. 

More information: Lingjing Xu et al, Nonlocal Population Sources Triggering Dinoflagellate Blooms in the Changjiang Estuary and Adjacent Seas: A Modeling Study, Journal of Geophysical Research: Biogeosciences (2021). DOI: 10.1029/2021JG006424

Citation: Study reveals nonlocal population sources triggering dinoflagellate blooms in Changjiang Estuary and adjacent seas (2021, December 28) retrieved 3 February 2023 from https://phys.org/news/2021-12-reveals-nonlocal-population-sources-triggering.html
This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only.

Explore further

Dissolved barium as a new quantitative indicator for Kuroshio incursion into the East China Sea

9 shares

Feedback to editors