Identification of the active microbes responsible for dissolved organic sulfur cycling along oxygen gradients in seasonally anoxic Mariager Fjord

This project investigates microbial community composition in the water column of Mariager Fjord, Denmark, under varying oxygen conditions. Mariager Fjord is a natural laboratory for studying microbial responses to oxygen availability due to its seasonal deoxygenation along the water column. Water samples were collected along a vertical transect spanning oxic and hypoxic layers. High-throughput sequencing of raw environmental DNA was conducted to characterize the microbial communities present at different depths. In addition, DNA-stable isotope probing (DNA-SIP) experiments were conducted using taurine, methionine and glucose to investigate the active microbial carbon turnover under varying oxygen conditions.