A two-year physicochemical and acoustic observation reveals spatiotemporal effects of earthquake-induced shallow-water hydrothermal venting on the surrounding environments

Abstract

Shallow-water hydrothermal vents have gained growing attention for their intricate characteristics caused by various epipelagic factors. The shallow-water hydrothermal system offshore Kueishan Island, Taiwan, situated in an earthquake-prone area, has prompted our exploration into the relationship between hydrothermal and seismic activities. Our 2-yr observation uncovered that the hydrothermal venting entered a silent period in November 2020, followed by a resurgence of activity after September 2021, coinciding with high-frequency shallow earthquakes occurring within 5 km of the vents. The pH level, dissolved inorganic carbon, alkalinity, pCO₂, ${\mathrm{CO}}_3^{2-}$, and sulfide served as indicators of hydrothermal activity, contributing to environmental changes in habitats during period transition. However, peering physicochemical and soundscape conditions, distinctions may still arise during two separate active periods. Through multivariate analysis, this study highlights the variability of shallow-water hydrothermal vents, emphasizing the necessity for more frequent and detailed investigations to further understand these extreme and dynamic marine ecosystems.