Algal cell viability assessment: The role of environmental factors in phytoplankton population dynamics. (April 2023)

• Record Type: Journal Article
• Authors: Wang, Yanyan; Zhai, Wei-dong; Wu, Chi
• Is Part Of: Marine pollution bulletin. Volume 189(2023)
• Publication Date: 2023-04
• Subjects: Digital holography -- Deep learning -- Cell viability -- Harmful algal blooms -- East China Sea; Marine pollution -- Periodicals; Marine Biology -- Periodicals; Water Pollution -- Periodicals; Mer -- Pollution -- Périodiques; Publications périodiques; Pollution des mers; Lutte antipollution; Electronic journals; 363.7394
• DOI: 10.1016/j.marpolbul.2023.114743
• Languages: English
• ISSNs: 0025-326X

Abstract

Abstract: The viability of algal cells is one of the most fundamental issues in marine ecological research. In this work, a method was designed to identify algal cell viability based on digital holography and deep learning, which divided algal cells into three categories: active, weak, and dead cells. This method was applied to measure algal cells in surface waters of the East China Sea in spring, revealing about 4.34 %–23.29 % weak cells and 3.98 %–19.47 % dead cells. Levels of nitrate and chlorophyll a were the main factors affecting the viability of algal cells. Furthermore, algal viability changes during the heating and cooling were observed in laboratory experiments: high temperatures led to an increase in weak algal cells. This may provide an explanation for why most harmful algal blooms occur in warming months. This study provided a novel insight into how to identify the viability of algal cells and understand their significance in the ocean. Graphical abstract: Unlabelled Image Highlights: Based on viability, we divided algal cells into active, weak, and dead cells. We found 4.34 %–23.29 % weak and 3.98 %–19.47 % dead cells in the East China Sea. The nitrate level had the greatest effect on the viability of algal cells. The warming process was more conducive to the occurrence of harmful algal blooms.