Laboratory observations of pH induced downward shifts in the vertical swimming behavior of the toxic raphidophyte Heterosigma akashiwo were used to estimate resultant effects on primary production rates. Based on empirical measurements of irradiance, cell distributions and specific primary production rates, total water column production decreased to 9.5×10-4 mg C m-2 h-1 or by 73% due to the lower irradiance at depth when pH induced downward swimming was factored into the calculations. Even inclusion of significantly increased specific primary production rates in a warm and acidified ocean did not negate the decrease in primary production due to downward swimming. If these laboratory predictions apply to the complex conditions in the coastal ocean, the results imply a lower probability of surface slick formation and blooms of H. akashiwo.
Kim H. & Menden-Deuer S., in press. Estimating the effects of ocean acidification on primary production of Heterosigma akashiwo. Proceedings of the 15th International Conference on Harmful Algae. Article.
Estimating the effects of ocean acidification on primary production of Heterosigma akashiwo
Published 17 March 2014 Science ClosedTags: biological response, laboratory, light, multiple factors, performance, phytoplankton, primary production, temperature