Oxygen and carbon fluxes from shallow unvegetated sediments in the Clarence Estuary, NSW, Australia under warming and ocean acidification conditions ...

• Main Authors: Simone, Michelle, Schulz, Kai, Oakes, Joanne, Eyre, Bradley D
• Format: Dataset
• Language: English
• Published: PANGAEA 2020
• Subjects: estuaries; Ocean acidification; sediment; warming; Treatment; Time point, descriptive; Replicates; DEPTH, sediment/rock; DEPTH, water; Surface area; Volume; Time in minutes; Salinity; Temperature, water; Oxygen saturation; Carbon, inorganic, dissolved; Carbon, organic, dissolved; pH; Experiment; Salinometer; Temperature sensor; LDO-probe; AIRICA analyzer Miranda; TOC analyser, Aurora 1030W; pH probe
• Online Access: https://dx.doi.org/10.1594/pangaea.924460; https://doi.pangaea.de/10.1594/PANGAEA.924460

Dissolved organic/inorganic carbon and oxygen fluxes from whole sediment core incubations subject to temperature and ocean acidification manipulations. Estuaries make a disproportionately large contribution of dissolved organic carbon (DOC) to the global carbon cycle, but it is unknown how this will change under a future climate. As such, the response of DOC fluxes from microbially dominated unvegetated sediments to individual and combined future climate stressors of warming (from Δ-3 °C to Δ+5 °C on ambient mean temperatures) and ocean acidification (OA, ~2 times the current partial pressure of CO2, pCO2) was investigated ex situ. Warming alone increased sediment heterotrophy, resulting in a proportional increase in sediment DOC uptake, with sediments becoming net sinks of DOC (3.5 to 8.8 mmol-C m-2 d-1) at warmer temperatures (Δ+3 °C and Δ+5 °C, respectively). This temperature response changed under OA conditions, with sediments becoming more autotrophic and a greater sink of DOC (1 to 4 times greater than ... : * DOC: DOC concentrations were measured via continuous-flow wet-oxidation using an Aurora 1030W total organic carbon analyser.* pH: calibrated to 3-point NIST buffer scale (R^2^ = 0.99). ...