Response of arctic bivalves to climate-induced changes in Kongsfjorden, RIS ID:10118

Individuals of the bivalve Astarte borealis (Schumacher, 1817) were marked and released in an enclosed area in 2012 and will be re-collected in September 2015. After thats, morphological analyses, as well as high-resolution samplings of shell carbonate by means of a MicroMill sampler for subsequent analysis of oxygen (delta 18O) and carbon (delta 13C) stable isotope ratios will be performed at the Alfred-Wegener-Institue in Bremerhaven. In the end the intra-annual variable shell growth rate of this bivalve and its relationship to external parameters (e.g. temperature, primary production) will be evaluated. Furthermore, a temperature coupled seasonal shell growth model in comparison with Serripes groenlandicus (Bruguiere, 1789) will be established. In order to investigate the physiological stress of sedimentation on A. borealis, test individuals will be exposed in vitro to 800mg L-1 over a period of 15 days. Mantle, foot, gill, and digestive gland tissues from experimental and control animals will be frozen in liquid nitrogen and analyzed at AWI in Bremerhaven to reveal the GSH/GSSG relationship as a short-term marker. Afterwards, the performance of the arctic-boreal species A. borealis will be compared with the arctic species S. groenlandicus.