Physiologische Auswirkungen der Ozeanerwärmung und -versauerung auf Kammmuscheln (Pectinidae)

This project investigated effects of ocean warming and acidification scenarios on the eurythermal King scallop Pecten maximus from Norway (boreal) and France (temperate) and the stenothermal Island scallop Chlamys islandica from Greenland (sub-Arctic), to compare different groups within a latitudinal gradient. The results of this thesis are discussed against the background of the concept of oxygen- and capacity-limited thermal tolerance. Test animals were long-term incubated at two CO2 concentrations (0.04 kPa = normocapnia vs. 0.11 kPa = hypercapnia) and at two temperatures ranging from 0-20 degrees Celsius (habitat temperature and temperature elevated by ca. 5 degree Celsius). Investigated parameters included haemolymph parameters (PO2, PCO2, pH, HCO3-, CCO2) to examine their abilities of extracellular oxygen support and acid-base capacity. Respiration rates of routine and maximal metabolic rates after exhaustive swimming were used to calculate aerobic scopes and recovery time of the animals. Several escape performance parameters such as number of claps, total, tonic, maximal and mean phasic force produced and total, tonic and phasic times needed during escaping were measured to assess their individual swimming performance.