Time Space and Hydrothermal Vents

There are global patterns in microbial communities of hydrothermal vents, but variations in local geochemistry may play a more significant role in structuring the microbiome. The volatility of hydrothermal vents causes a variation in geochemistry over time, especially after eruptions. Investigations into the organisms that thrive within these environments has captured the imagination of the scientific community and public. To understand how these environments function and influence the global ocean a working knowledge of the microbiome’s role and structure is required.  

Researchers performed metagenome and metatranscriptome analyses of samples from 3 geochemically distinct vents at Axle sea mount over 3 years. The main findings were that each vent hosted distinct populations of microbes with different metabolic functions that changed vent geochemistry. A high proportion of methanotrophs at two sites was linked to increased hydrogen drawdown.  These populations were stable through time even after an eruption event in 2015.

The fluid chemistry, fluid dynamics, energetics and physical structure of the vents were seen to all play roles in the structuring of these microbial communities. The paper seems to overlook the role of microbial interactions which could be key to a better understanding of the big picture.

Fortunato, C. S., Larson, B., Butterfield, D. A., & Huber, J. A. (2018). Spatially distinct, temporally stable microbial populations mediate biogeochemical cycling at and below the seafloor in hydrothermal vent fluids. Environmental microbiology, 20(2), 769-784.