Medium-term exposure of the North Atlantic copepodCalanus finmarchicus(Gunnerus, 1770) to CO2-acidified seawater: effects on survival and development

[摘要] The impact of medium-term exposure to CO₂-acidified seawater onsurvival, growth and development was investigated in the North Atlanticcopepod Calanus finmarchicus. Using a custom developed experimentalsystem, fertilized eggs and subsequent development stages were exposed tonormal seawater (390 ppm CO₂) or one of three different levels ofCO₂-induced acidification (3300, 7300, 9700 ppm CO₂). Followingthe 28-day exposure period, survival was found to be unaffected by exposureto 3300 ppm CO₂, but significantly reduced at 7300 and 9700 ppmCO₂. Also, the proportion of copepodite stages IV to VI observed in thedifferent treatments was significantly affected in a manner that may indicatea CO₂-induced retardation of the rate of ontogenetic development.Morphometric analysis revealed a significant increase in size (prosomelength) and lipid storage volume in stage IV copepodites exposed to 3300 ppmCO₂ and reduced size in stage III copepodites exposed to 7300 ppmCO₂. Together, the findings indicate that a pCO₂ level ≤2000 ppm (the highest CO₂ level expected by the year 2300) willprobably not directly affect survival in C. finmarchicus.Longer term experiments at more moderate CO₂ levels are, however,necessary before the possibility that growth and development may be affectedbelow 2000 ppm CO₂ can be ruled out.

[学科分类] 地球化学与岩石