Dissolved organic matter, microbial activities and communities from water samples during SONNE cruise SO288

Sea water samples were collected during the RV SONNE cruise SO288 (15 January 2022–15 February 2022) within the framework of the HOMER project in the Southeast Pacific off Chile . At three stations, water samples were collected at 12 depths throughout the water column using standard 12 L Niskin-type bottles attached to a CTD rosette and represented the different pelagic zones: 25 m and 100 m (epipelagic), 250, 500, 750 and 1,000 m (mesopelagic), 1,500- 3800 m (bathypelagic; here different depths were sampled due to differences in bathymetry), and 4,000, 4,500 and 5,000 m (abyssopelagic). Temperature, oxygen, and pressure were measured using a Sea-Bird SBE 9-plus CTD system (Sea-Bird Electronics, Inc.), and chlorophyll a (Chl a) concentrations were detected using a WETStar fluorometer (WET Labs).