Ocean Acidification and Organic Matter Enrichment Alter Carbonate Sediment Metabolism Through Different Pathways ...

• Main Authors: Lantz, Coulson A, Schulz, Kai Georg, Eyre, Bradley D
• Format: Article in Journal/Newspaper
• Language: English
• Published: PANGAEA 2020
• Subjects: Benthos; Calcification/Dissolution; Coast and continental shelf; Containers and aquaria 20-1000 L or < 1 m**2; Entire community; Laboratory experiment; Other; Primary production/Photosynthesis; Respiration; Soft-bottom community; South Pacific; Temperate; Ocean Acidification International Coordination Centre OA-ICC; Ocean acidification
• Online Access: https://dx.doi.org/10.1594/pangaea.905748; https://doi.pangaea.de/10.1594/PANGAEA.905748

Ocean acidification (OA) and organic matter enrichment (due to coastal eutrophication) could act in concert to shift coral reef carbonate sediments from a present state of net calcification to a future state of net dissolution, but no studies have examined the combined effect of these stressors on sediment metabolism and dissolution. This study used 22-hour incubations in flume aquaria with captive sediment communities to measure the combined effect of OA and organic matter (OM) enrichment, on coral reef sediment gross primary productivity (GPP), respiration (R), and net calcification (Gnet). Relative to control sediment communities, both OA ( 1000 µatm) and OM enrichment (+ 40 µmol C/L) significantly decreased rates of sediment Gnet by 98% and 15% mmol CaCO3/m**2/h, respectively , but the mechanism behind this decrease differed. The OA-mediated transition to net dissolution was geochemical, as rates of GPP and R remained unaffected and dissolution was solely enhanced by a decline in the aragonite saturation ... : Supplement to: Lantz, Coulson A; Schulz, Kai Georg; Eyre, Bradley D (in review): Ocean Acidification and Organic Matter Enrichment Alter Carbonate Sediment Metabolism Through Different Pathways. Journal of Geophysical Research: Oceans ...