Potential Temporal and Spatial Trends of Oceanographic Conditions with the Bloom of Ulva Prolifera in the West of the Southern Yellow Sea

Yufeng Pan,Xue Liu,Guangxue Li,Jinghao Shi,Shidong Liu,Xiangdong Wang,Jun Liang,Dong Ding

doi:10.3390/rs13214406

Abstract

Based on National Oceanic and Atmospheric Administration/Advanced Very High-Resolution Radiometer (NOAA/AVHRR) remote sensing and Cross-Calibrated Multi-Platform (CCMP) wind field data from 2007 to 2019, oceanographic conditions are analysed, respectively, in the Source Area (SA) and Typical Bloom Area (TBA) of Ulva prolifera (U. prolifera) in the west of the Southern Yellow Sea (SYS) using Sea Surface Temperature (SST), Suspended Sediment Concentration (SSC) and Wind Speed over the years. The results indicate that the annual maximum SST Difference (SSTD) between U. prolifera SA and TBA is strongly consistent with the intensity of U. prolifera, and a high SST Warming Rate (WR) from May to July may constrain the U. prolifera blooms. The Taiwan Warm Current (TWC), crossing Yangtze River Estuary northward from March to April, leads to SST increasing in the SA and becomes a key trigger for the growth of U. prolifera in the early period. The amount of U. prolifera may decrease in the early period because of the lower light intensity with high SSC and turbidity in SA. The summer monsoon is one of determinants for the spread of U. prolifera, and the distribution of U. prolifera reaches its highest point with a higher mean wind speed in the TBA.

Highlights

Since 2008, Enteromorpha in the west of Southern Yellow Sea (SYS) has bloomed and gathered in large numbers, and its presence has seriously affected coastal fisheries and tourism in Jiangsu and Shandong Province, becoming one of the most serious marine events in China [1]
This is because south-southeast wind prevails in the SYS in summer and the Sea Surface Temperature (SST) of 24~27 ◦ C are within the suitable growth temperature interval of U. prolifera of 10~30 ◦ C, which is the one of the main reasons why U. prolifera grows more and rapidly [6,7]
The SST in the Source Area (SA) reached the appropriate growth temperature of U. prolifera earlier than usual. It indicates that the Taiwan Warm Current (TWC) crosses the Yangtze River Estuary northward from March to April, causing the increase of the SST off the coast of Rudong, which triggers the rapid growth of U. prolifera in SA

Summary

Introduction

Since 2008, Enteromorpha in the west of Southern Yellow Sea (SYS) has bloomed and gathered in large numbers, and its presence has seriously affected coastal fisheries and tourism in Jiangsu and Shandong Province, becoming one of the most serious marine events in China [1]. Studies indicate that the presence of Enteromorpha impacts that bloom in the SYS mostly originate along the laver breeding coast of Jiangsu Province [2,3,4], where the dominant species is Ulva prolifera (U. prolifera) [5]. This is because south-southeast wind prevails in the SYS in summer and the Sea Surface Temperature (SST) of 24~27 ◦ C are within the suitable growth temperature interval of U. prolifera of 10~30 ◦ C, which is the one of the main reasons why U. prolifera grows more and rapidly [6,7]. This is because south-southeast wind prevails in the SYS in summer and the Sea Surface Temperature (SST) of 24~27 ◦ C are within the suitable growth temperature interval of U. prolifera of 10~30 ◦ C, which is the one of the main reasons why U. prolifera grows more and rapidly [6,7]. 4.0/).

Methods

Discussion

Conclusion