Chair: Alistair Hobday
Kristen Karsh (1)*, Juan-Diego Gaitán-Espitia (2), Philip W. Boyd (3)
1 Antarctic Climate & Ecosystems CRC, Hobart, Tasmania, 7000, Australia
2 CSIRO Marine and Atmospheric Research, Hobart, Tasmania, 7000, Australia
3 Institute for Marine and Antarctic Studies, University of Tasmania, Hobart, Tasmania, 7000, Australia
Background
A changing climate is modifying marine productivity through reshaping physical and chemical properties of the ocean. Here we examine the individual and interactive effects of two predicted changes, increasing temperature (arguably the most fundamental through its control on biological rates) and decreasing pH (arguably the most extreme in terms of relative rate of change).
Methods
Temperature performance curves (TPCs) quantitatively characterise the relationship between biological rates and temperature. We analyse TPCs for a range of traits related to fitness and biogeochemical function in a marine diatom.
Findings
We show changes to the thermal sensitivity of individual traits and the whole organism response when pH is decreased to predicted 2100 levels and relate these changes to the underlying physiological mechanisms.
Conclusions
Our findings demonstrate the importance of considering interactive effects when predicting the responses of marine productivity to future environmental change.