Influence of Manila clam (Ruditapes philippinarum) aquaculture on the partitioning of organic carbon oxidation coupled to sulfate- and iron reduction in the sediments of the Keunso Bay, Yellow Sea

Abstract

Although it represents the third highest production (4,228,594 tonnes in 2016) in global shellfish aquaculture, little is known about the effects of Manila clam (Ruditapes philippinarum) aquaculture on the sediment biogeochemistry. We investigated the rates and pathways of anaerobic organic carbon (Corg) oxidation in highly bioturbated (HB) sediments by the R. philippinarum aquaculture and poorly bioturbated (PB) sediments in the Keunso Bay, Yellow Sea. As a result of increasing solute exchange through reworking and irrigation activities, anaerobic Corg oxidation rates at HB (38.8 mmol m-2 d-1) were about twice as high as that at PB (26.8 mmol m-2 d-1). Microbial Fe(III) reduction pre-dominated Corg oxidationpathway at HB, comprising 55