1. Biological Impacts on marine organisms in high CO2 world Yoshihisa Shirayama Seto Marine Biological Laboratory Kyoto University

2. contents Direct chronic impacts of raised concentration of atmospheric CO2 on shallow water organisms –Adults –Early development Acute impacts of largely raised concentration of sea- water CO2 on deep-sea organisms due to ocean sequestration –Lethal –Sublethal –Benthic chamber

3. Estimated pH change of the seawater in AD 2100 7.6 7.8 8.0 8.2 2004006008001000 Before the industrial revolution Present 2100 CO2 IPCC IS92a H PCO 2 (ppm) B1 Scenario A1F1 Scenario

4. Meaning of Ocean Sequestration CO2 concentration Year A: no sequestration; B: 50% at 1500m; C: 50% at 4000%; D: 100% at 1500m; E: 100% at 4000m

5. Approach Shallow water – +200 ppm to +2,000 ppm air bubbling – long-term culturing (up to 6 months) –Calcareous shelled animals Sea urchin snail

6. Shallow water calcareous species used in the long-term experiment Hemicentrotus pulcherrimus Echinometra mathaei Strombus luhuanus

7. Survival: Experiment 1 Control 560ppm

8. Growth: Hemicentrotus pulcherrimus Experiment 1 Experiment 3 Control 109% CO 2 65% Control 155% CO 2 100%

9. Growth : Echinometra mathaei Experiment 1 Experiment 3 Control 51% CO 2 36% Control 26% CO 2 -7%

10. Growth: Strombus luhuanus (Expt 1) Length Weight Control 22% CO 2 17% Control 74% CO 2 56%

11. Damage of shell at +2000 ppm

12. Approach to Deep-sea Sequestration modification Laboratory experiment – +2,000 ppm to +20,000 ppm air bubbling – lethal impacts – Sublethal impacts in situ experiment – benthic chamber – +5000 ppm, +10000 ppm

13. +5000 ppm is not acutely lethal on adult copepods

14. Impacts on reproduction of copepods

15. 8.2 8.07.87.67.47.27.0 6.8 6.6 0 20 40 60 80 100 control +500 +1000 +2000 +5000 +10000 0 20 40 60 80 100 ppm pH A B Fertilized eggs, %

16. Fig 4 4 cell/fert 2 cell/fert 1 cell/fert A 0 20 40 60 80 100 control (8.0)(7.8)(7.6) (7.4)(7.0)(6.8) +500+1000+2000+5000 +10000ppm (pH) 0 20 40 60 80 100 B Cleavaged embryos,%

17. Impact of high CO2 in the early life stage of sea urchins

18. A B CD E F G HIJK L Morphology of sea urchin larvae in high CO2 sea water

19. Benthic Chamber

21. Experiments so far conducted CruiseDepth (m)Exposure time (h) Exposure pCO2 (ppm) K12-02 2,000 306500 (control) 5,000 (LCO2) 20,000 (HCO2) KT13-0277 K13-03375

22. Abundance of meiobenthos No. of individuals in 0-3 cm layer

23. Abundance of Bacteria Mean of 0-3cm surface

24. Future research needs Shallow water –Impacts on reproduction –More precise simulation (daily fluctuation etc.) –Ecosystem approach –Modeling Deep-sea sequestration –Precise simulation of CO2 change –More information on sublethal impacts –In situ approach especially ecosystem level –Modeling Public outreach