https://doi.org/10.5061/dryad.tdz08kq6w

The oxygen optode and winkler data include oxygen concentration measurements made during in-situ benthic chamber experiments at multiple sites across the Pacific Ocean.  The optodes were pre-calibrated prior to the lander experiments and made during different experimental durations (1-2 days).  The experiments were undertaken in-situ between approximately 4100-5200m depth.  The winkler data set also contains oxygen concentration data from ex-situ core incubation experiments conducted in the dark at in-situ temperature.   The voltages were measured between two points on the surface of nodules that were immersed in Instant Ocean water at two temperatures (21 and 5 degrees Celsius) using a high precision multimeter. An excel sheet showing the total oxygen change in each in-situ chamber experiment and nodule abundance, total surface area of nodules, and average surface area of nodules is also provided. In-situ O2 microprofiling data are also provided.  Correlations between the relative abundance of specific microbial taxa (provided) and total oxygen change were undertaken based on microbial DNA sequence data provided in the NCBI link supplied in the paper.

Description of the data and file structure

The optode and Winkler data sets show the oxygen concentration measurements made during in-situ benthic chamber experiments at multiple sites across the Pacific Ocean.  The optode measurements in the cruise 5D, 5E and 7A folders are from pre-calibrated optodes. The optode data from the APEI1, 4, and 7, and OMS and UK1 sheets were derived from a factory calibration.  The time the optode measurements were made is shown in each sheet and the time each Winkler sample was collected is also shown.  The ex-situ data set includes all the information necessary to derive the fluxes including the duration of the experiment (48hr), the oxygen concentration in the T=0 and T=48 samples, and the volume of the cores. The voltage data set includes the background voltages measured using only Instant Water and the voltages measured during replicate measurements on the different nodules. An Excel sheet showing the total oxygen change in each in-situ chamber experiment and nodule abundance, total surface area of nodules, and average surface area of nodules is also provided so correlations between nodule parameters and the total oxygen change can be determined.  In-situ O2 microprofiling data are also provided.  . Correlations between the relative abundance of specific microbial taxa (provided) and total oxygen change were undertaken based on microbial DNA sequence data provided in the NCBI link supplied in the paper.

Data files include:

• Optode data from benthic chamber lander deployments - Oxygen concentrations in μmol per liter measured by calibrated oxygen optodes through time in h in the different benthic chamber incubations. The AKS number refers to specific benthic chamber lander deployments. NULL means no data available.
• Winkler data - Oxygen concentrations in μmol per liter determined by Winkler analysis on water samples collected periodically from the chambers. The AKS number refers to specific benthic chamber lander deployments.
• Voltages - Voltage potentials (V) measured on the surface of polymetallic nodules and background voltages measured without nodules. NULL means no data available.
• Surface area to DOP dataset - this dataset includes nodule surface area information and dark oxygen production data.
• Microbial abundance versus DOP dataset - this dataset includes the abundance of specific microbial taxa as a function of the dark oxygen production data.
• Microprofiling dataset - this dataset includes information on how oxygen concentration (in μmol per liter) changes as the micro profiler transitioned from just above the sediment water interface down into the sediment allowing sediment community oxygen consumption rates to be determined.
• Microbial abundances - this dataset showcases the relative abundances of microbial taxa from sediments recovered from the benthic chamber lander during the NORI-D cruises. NULL means no data available.