Hale, Rachel (2025): Sediment disturbance experiment data with samples from the Chatham Rise, Southwest Pacific [dataset]. PANGAEA, https://doi.org/10.1594/PANGAEA.975706,

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In: Hale, R (2025): Effects of an experimental in situ seabed disturbance on deep-sea benthic ecosystem function and macro-infaunal community structure on the Chatham Rise, Southwest Pacific [dataset bundled publication]. PANGAEA, https://doi.org/10.1594/PANGAEA.975610

We examined changes in environmental parameters following an experimental benthic disturbance using a modified plough (estimated 15 cm penetration) on the Chatham Rise (~450 m depth), Aotearoa/New Zealand. Sediment core retrievals were undertaken using an Oceans Instruments MC-800 multicorer fitted with six 70 cm long polycarbonate core tubes with 9.52 cm internal diameter that took place pre-disturbance on 16-17 June 2019 (voyage TAN1903), post-disturbance on 24-25 June 2019 (TAN1903) and one-year post-disturbance on 14-19 June 2020 (TAN2005). In order to determine any background changes in the larger surrounding area between years (2019, 2020), an additional reference site with similar hydrographic and sediment attributes (REF, depth = 455 m), located approximately 15 km to the north-west of the Butterknife (Figure 1B), was also sampled in the pre-disturbance period (n = 2, TAN1903) and one-year post-disturbance (n = 3, TAN2005). Sediment flux measurements were taken from subsampled multicores (0-10 cm layer) using sealed stirred aquaria maintained at bottom water conditions in the controlled temperature laboratory on RV Tangaroa. Sediment community oxygen consumption (SCOC) was measured via a sensor inserted through a sampling port in the chamber lid (FireStingO2, Pyroscience) upon commencement of the incubation and approximately every 2 hours until seawater oxygen concentration was depleted to 85-90% of the initial concentration to obtain a time-series of 3-6 measurements of oxygen consumption. Absolute concentrations of nutrients: ammonium ([NH4-N]), nitrite + nitrate ([NOx-N]), and phosphate ([PO4-P]), from overlying seawater samples (15 mL, 0.45 μm filtered, frozen at -20°C upon collection) taken at time 0 and upon termination of the SCOC experiment were quantified using an auto-analyser.