Life Threatened in Acidic Coastal Waters

Coastal Environmental and Ecosystem Issues of the East China Sea, Eds., A. Ishimatsu and H.-J. Lie, pp. 283–303. © by TERRAPUB and Nagasaki University, 2010. Atsushi ISHIMATSU and Awantha DISSANAYAKE


Abstract:  Increasing atmospheric CO2 is not only increasing global temperature but also rapidly acidifying seawater through formation of carbonic acid (ocean acidification). Emerging evidence from laboratory research indicates that predicted changes in ocean environments could have profound implications for marine ecosystem, however, it is relatively unclear how marine biota will respond to ocean warming and acidification. Furthermore, most published papers have used future atmospheric CO2 concentration in their experimental protocols, ignoring spatial heterogeneity of seawater carbonate chemistry, which is most manifested in coastal regions and deep sea.

This paper first summarizes empirical evidence on effects of CO2 on marine organisms, and then discusses the importance of considering local CO2 conditions to improve our prediction ability on the fate of marine organisms in acidified oceans. Marine molluscs have been shown to be highly sensitive to elevations of ambient CO2, in particular during larval shell formation. In addition, data have been accumulated on sublethal impacts on morphology, physiology and behavior. Early development of echinoderms are also significantly affected by elevations of seawater pCO2, however, there seems to be a difference in interspecies CO2 sensitivity from different latitudes and also a high intra-species sensitivity. Gonad development can be severely impacted by high CO2. As compared with CO2 sensitivity known for molluscs and echinoderms, some crustaceans, particularly copepods and amphipods, and fish appear to be less vulnerable to CO2.

Anthropogenic impacts on coastal environment are multifaceted and complex. Scientific endeavor is of utmost necessity to secure this most productive marine region. Investigations reflecting local biotic and abiotic conditions are needed to precisely predict how coastal ecosystem will shape in the face of changing environment.

Keywords: ocean acidification, CO2, pH, coastal environment, estuary, early


Read the full paper here.