Nitrate penetration depths under advective conditions in sand from the Janssand, Germany intertidal flat

The mpbvdnf_penetration_depths.csv file contains data in the following columns:event_label - the latitude from which samples were collected. Units = degrees and decimal minutes North latitude.season - the nominal season in which the sediment cores used in each measurement were collected.light - a factor identifying whether measurements were made in the dark or the light.flow_rate - the vertical, downward porewater flow rate imposed on each sediment core while measurements were being made. Units = mL min-1. elapsed_time - the amount of time elapsed since measurements began at the onset of porewater flow. Units = hours.depth_o2 - The oxygen penetration depth. Units = m. The oxygen penetration depth is defined as the depth below the sediment surface in the sediment core at which the oxygen concentration reached zero.depth_nox - The NOx penetration depth. Units = m. The NOx penetration depth is defined as the depth below the sediment surface in the sediment core at which the NOx concentration reached zero.Methods: Penetration depths were measured by pumping site seawater down through the sediment core at a known flow rate. When the pump was switched on, we immediately began measuring oxygen and NOx depth profiles using parallel oxygen microsensors and NOx microbiosensors. Depth profiles were measured repeatedly over a period of 2 to 9 hours following the onset of porewater flow to observe changes in penetration depth over time.