Interactions between seagrasses and mussels: CO2, pH and calcification
(English)In: Estuarine, Coastal and Shelf Science, ISSN 0272-7714, E-ISSN 1096-0015Article in journal (Refereed) Submitted
Mussels and other bivalves commonly found in tropical seagrass meadows are thought to increase seagrass productivity, and seagrass photosynthesis, through raising the pH of the surrounding water, has been shown to increase rates of calcification in calcareous algae. The effects of seagrass-driven increases in pH on mussel calcification and possible feedback effects of mussel metabolism on seagrass photosynthesis were studied in a seagrass bed on the south-western coast of Zanzibar, Tanzania. Seagrasses and mussels (Pinna muricata) were enclosed, separately or together, in transparent plastic cylinders. The pH and photosynthesis were measured and seawater samples were taken from the experimental cylinders to determine total alkalinity and total inorganic carbon concentration. Cylinders containing only sediments were exposed to light and dark and used as controls. The results showed no effects of increased pH on calcification rates in the mussels. However, photosynthetic rates of the seagrass Thalassia hemprichii rose by up to 15% in the presence of mussels, possibly as a result of water stirring caused by the mussels’ filter feeding and/or CO2 released by their respiration.
Inorganic carbon, mussels, pH, photosynthesis, seagrasses
Research subject Plant Physiology
IdentifiersURN: urn:nbn:se:su:diva-55866OAI: oai:DiVA.org:su-55866DiVA: diva2:408777