Overturning circulation structures the microbial functional seascape of the South Pacific

Global overturning circulation partitions the deep ocean into regions with unique physicochemical characteristics, but the extent to which these water masses represent distinct ecosystems remains unknown. Here, we integrate extensive genomic information with hydrography and water mass age to delineate microbial taxonomic and functional boundaries across the South Pacific. Prokaryotic richness steeply increases with depth in the surface ocean, forming a “phylocline”, below which richness is consistently high, dipping slightly in highly aged water. Reconstructed genomes self-organize into six spatially-distinct taxonomic cohorts and ten functionally-distinct biomes that are primarily structured by wind-driven circulation at the surface and density-driven circulation at depth. Overall, water physicochemistry, modulated at depth by water age, drives microbial diversity and functional potential in the pelagic ocean., , , # Overturning circulation structures the microbial functional seascape of the South Pacific

[Access this dataset on Dryad](https://doi.org/10.5061/dryad.s4mw6m9h7)

This dataset supports the publication titled *\"Overturning circulation structures the microbial functional seascape of the South Pacific\"* by Kolody et al. (DOI 10.1126/science.adv6903) and full methods are available in the supplementary text. It presents high-resolution genomicand amplicon data from the South Pacific Ocean in the context of the environmental data sampled along the GO-SHIP Pacific 18 (P18) transect. The data include prokaryotic metagenome-assembled genomes (MAGs), 16S and 18S rRNA gene amplicon data, functional annotations (KEGG, CAZy), and physical/chemical oceanographic metadata. These files collectively enabled the study of microbial diversity, biogeography, and functional potential as shaped by ocean overturning circulation and water mass age.

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## Description of the data and file structure

The dat...,