Distribution of corrosive microbial communities in rust layers of steel immersed in seawater.

Abstract

In this paper, high-throughput sequencing technology was adopted to visualize the microbial communities on the surfaces of two types of carbon steel immersed in Sea Area Ⅰ. The results showed that different microbial communities were formed on different carbon steel surfaces, in which the genus with the highest abundance on the surface of Q235 was Escherichia-Shigella, while anaerobic Desulfovibrio on the surface of 921a was the most abundant, and the dominant genus varied with the depth of the rust layer. In addition, the distribution of sulfate-reducing bacteria (SRB) on the surface of Q235 submerged in Sea Area Ⅱ was compared with the sulfate-reducing bacteria's distribution in Sea Area Ⅰ, using the environmental factors correlation analysis. The results showed that the concentrations of Ca²⁺, Na⁺, K⁺, Mg²⁺, and Al³⁺ were positively correlated with the distribution of SRB, while the concentrations of Cu²⁺, Zn²⁺, SO₄ ^2-, Cl^-, NO₃ ^-, and organic carbon were negatively correlated with it. Furthermore, there was a highly significant correlation between each geochemical factor and Desulfotomaculum (p < 0.01).