Insights into how characteristics of dissolved algal organic matter affect the efficiency of modified clay in controlling harmful algal blooms

Na Chu; Xihua Cao; Yafan Wang; Wenbin Jiang; Xiaomiao Zang; Xiuxian Song; Yuanhong Xu; Zhiming Yu

doi:10.1016/j.marpolbul.2024.116437

Insights into how characteristics of dissolved algal organic matter affect the efficiency of modified clay in controlling harmful algal blooms

Mar Pollut Bull. 2024 May 10:203:116437. doi: 10.1016/j.marpolbul.2024.116437. Online ahead of print.

Authors

Na Chu¹, Xihua Cao², Yafan Wang³, Wenbin Jiang⁴, Xiaomiao Zang⁵, Xiuxian Song⁶, Yuanhong Xu⁷, Zhiming Yu⁸

Affiliations

¹ Institute of Biomedical Engineering, College of Life Science, Qingdao University, Qingdao 266071, China; CAS Key Laboratory of Marine Ecology and Environmental Sciences, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China. Electronic address: chuna@qdio.ac.cn.
² CAS Key Laboratory of Marine Ecology and Environmental Sciences, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China; University of Chinese Academy of Sciences, Beijing 100049, China. Electronic address: caoxh@qdio.ac.cn.
³ CAS Key Laboratory of Marine Ecology and Environmental Sciences, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China; College of Marine Science and Biological Engineering, Qingdao University of Science and Technology, Qingdao 266042, China. Electronic address: wangyf699@163.com.
⁴ CAS Key Laboratory of Marine Ecology and Environmental Sciences, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China. Electronic address: jiangwenbin@qdio.ac.cn.
⁵ CAS Key Laboratory of Marine Ecology and Environmental Sciences, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China. Electronic address: zangxm5956@163.com.
⁶ CAS Key Laboratory of Marine Ecology and Environmental Sciences, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China; University of Chinese Academy of Sciences, Beijing 100049, China. Electronic address: songxx@qdio.ac.cn.
⁷ Institute of Biomedical Engineering, College of Life Science, Qingdao University, Qingdao 266071, China. Electronic address: yhxu@qdu.edu.cn.
⁸ CAS Key Laboratory of Marine Ecology and Environmental Sciences, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China; University of Chinese Academy of Sciences, Beijing 100049, China. Electronic address: zyu@qdio.ac.cn.

PMID: 38733893
DOI: 10.1016/j.marpolbul.2024.116437

Abstract

Dissolved algal organic matter (dAOM) originating from harmful algal blooms (HABs) can deteriorate the quality of municipal water supplies, threaten the health of aquatic environments, and interfere with modified clay (MC)-based HABs control measures. In this study, we explored the composition of dAOM from Prorocentrum donghaiense, a typical HAB organism, and assessed the influence of dAOM on MC flocculation. Our results suggested that dAOM composition was complex and had a wide molecular weight (MW) distribution. MW and electrical properties were important dAOM characteristics affecting flocculation and algal removal efficiency of MC. Negatively charged high-MW components (>50 kDa) critically affected algal removal efficiency, reducing the zeta potential of MC particles and leading to small and weak flocs. However, the effect of dAOM depended on its concentration. When the cell density of P. donghaiense reached HAB levels, the high-MW dAOM strongly decreased the algal removal efficiency of MC.

Keywords: Algal removal efficiency; Dissolved algal organic matter; Electrical property; Flocculation; Modified clay; Molecular weight.