The effect of CO_2 acidified sea water and reduced salinity on aspects of the embryonic development of the amphipod Echinogammarus marinus (Leach)

摘要

We investigated the effect of CO_2 acidified sea water (S = 35,22 and 10_(PSU)) on embryonic development of the intertidal amphipod Echinogammarus marinus (Leach). Low pH, but not low salinity (22_(PSU)), resulted in a more protracted embryonic development in situ although the effect was only evident at low salinity. However reduced salinity, not pH, exerted a strong significant effect, on numbers and calcium content of hatchlings. Females exposed to low salinity (10_(PSU)) did not carry eggs through to hatching. There was no significant difference in the number of viable hatchlings between females cultured in 22 and 35_(PSu) but the exoskeleton of the juveniles at 22_(PSU) contained significantly less calcium. Ocean acidification may affect aspects of E marinus development but exposure to realistic low salinities appear, in the short term, to be more important in impacting development than exposure to CO_2 acidified sea water at levels predicted for 300 years time.