Comparative Study on Removal Efficiency and Mechanisms by Algicidal Bacteria and Modified Clay on Skeletonema costatum
This study focused on the typical red tide alga Skeletonema costatum in coastal waters of China,comparing the algal removal efficiency of a bioflocculant derived from a strain of algicidal bacteria Pae-bubacillus sp.and that of chemically modified clay.Through scanning electron microscopy,Zeta potential analysis,chlorophyll fluorescence characterization,and dissolved organic matter(DOM)composition anal-ysis,the algal removal mechanisms underlying these two methods were explored.The results demonstra-ted that both methods effectively removed S.costatum,with removal rates exceeding 94%within 24 hours.However,significant differences exist in the two mechanisms:modified clay rapidly coagulates al-gal cells through electrostatic neutralization,whereas the algicidal bacteria disrupts and kills algal cells di-rectly or indirectly(e.g.,through photosynthetic inhibition).Compared to modified clay,the algal re-moval process of algicidal bacteria generates algal DOM,such as soluble microbial products,protein-like substances,and fulvic acid-like components,which are subsequently degraded or assimilated over time.These results offer new avenues for the development of emergency integrated algal control technologies and their applications in red tide mitigation.
red tideSkeletonema costatumalgicidal bacteriamodified clayalgal removal mechanism
万方数据
维普
