ICRS 2016 Humanes Adriana

Transcript

1. AIMS: Australia’s tropical marine research agency. www.aims.gov.au ICRS HAWAI’I 2016 Adriana Humanes, Bette Willis, Katharina Fabricius and Andrew Negri A.Humanes@aims.gov.au Cumulative effects of sediments, nutrient enrichment and high temperatures compromise the early life history stages of the coral Acropora tenuis
2. AIMS: Australia’s tropical marine research agency. www.aims.gov.au ICRS HAWAI’I 2016
3. AIMS: Australia’s tropical marine research agency. www.aims.gov.au ICRS HAWAI’I 2016
4. AIMS: Australia’s tropical marine research agency. www.aims.gov.au ICRS HAWAI’I 2016 Climate change: Sea surface temperature Terrestrial runoff: Nutrients and sediments Current situation of coral reefs worldwide
5. AIMS: Australia’s tropical marine research agency. www.aims.gov.au ICRS HAWAI’I 2016 Local changes in the Great Barrier Reef (GBR) Nutrient and sediment input in the GBR increased since 1823: Nitrogen Phosphorus Source: eAtlas Frequency of exposure Frequency of exposure to 2nd water types Plume exposure Suspended sediments Australia
6. AIMS: Australia’s tropical marine research agency. www.aims.gov.au ICRS HAWAI’I 2016 Jones et al. 2015 Corals’ early life history stages Runoff and high temperatures can coincide with coral spawning in the GBR
7. AIMS: Australia’s tropical marine research agency. www.aims.gov.au ICRS HAWAI’I 2016 ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ Great Barrier Reef (GBR) Previous studies on the effects of single factors Sperm mobility Gametes viability Abnormal embryos Larval survivorship Settlement
8. AIMS: Australia’s tropical marine research agency. www.aims.gov.au ICRS HAWAI’I 2016 ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ Great Barrier Reef (GBR) Sperm mobility Gametes viability Abnormal embryos Larval survivorship Settlement No previous studies on the effects of simultaneous factors
9. AIMS: Australia’s tropical marine research agency. www.aims.gov.au ICRS HAWAI’I 2016 Gamete collection and separation Acropora tenuis Temperature 27, 30, and 32°C Nutrient enrichment 0, 0.3 and 0.6 mg/l organic carbon Low Medium High National Sea Simulator (SeaSim) Suspended sediments 0, 5, 10, 30 and 100 mg/l
10. AIMS: Australia’s tropical marine research agency. www.aims.gov.au ICRS HAWAI’I 2016 Experiments Fertilization 1st cleavage (2 h) 2nd cleavage (3 h) Experiment 1 8 cell (4 h) Prawn chip stage (7-10 h) Experiment 2 Experiment 3 Larvae (5-day-old)) Round stage (36 h) Tear drop stage (54-98 h) Experiment 4 Recruit
11. AIMS: Australia’s tropical marine research agency. www.aims.gov.au ICRS HAWAI’I 2016 % Fertilization 0 20 40 60 80 100 0 5 10 30 100 Suspended sediments (mg/l) 27 30 32 1. Fertilization Suspended sediments and temperature Fertilization threshold levels decreased with warming temperatures IC50 27°C = 37 mg l-1 IC50 30°C = 25 mg l-1 IC50 32°C = 18 mg l-1
12. AIMS: Australia’s tropical marine research agency. www.aims.gov.au ICRS HAWAI’I 2016 1. Fertilization Mechanism of action: - Sperm limitation by their entanglement in sediments % Fertilization 0 20 40 60 80 100 0 5 10 30 100 Suspended sediments (mg/l)
13. AIMS: Australia’s tropical marine research agency. www.aims.gov.au ICRS HAWAI’I 2016 % Fertilization 0 20 40 60 80 100 0 5 10 30 100 Suspended sediments (mg/l) 27 30 32 1. Fertilization Suspended sediments and temperature Mechanism of action: -Reduction in the sperm motility. -Impairment of biochemical processes. (Omori et al. 2001, Lam et al. 2015)
14. AIMS: Australia’s tropical marine research agency. www.aims.gov.au ICRS HAWAI’I 2016 2. Embryo development % Settlement 0 20 40 60 80 100 0 5 10 30 100 Suspended sediments (mg/l) Suspended sediments and nutrient enrichment Settlement decreased with the individual effect of suspended sediments Mucous production Abrasive damage Mechanism of action: -Mucous production -Abrasive damage (Hess et al. 2015)
15. AIMS: Australia’s tropical marine research agency. www.aims.gov.au ICRS HAWAI’I 2016 2. Embryo development % Settlement Suspended sediments (mg/l) Low enrichment Medium enrichment High enrichment Suspended sediments and nutrient enrichment Settlement decreased with suspended sediments and nutrient enrichment in an additive way 0 20 40 60 80 100 0 5 10 30 100
16. AIMS: Australia’s tropical marine research agency. www.aims.gov.au ICRS HAWAI’I 2016 2. Embryo development Settlement decreased with suspended sediments and nutrient enrichment in an additive way IC50 Low = >100 mg/l IC50 Medium = 64 mg/l IC50 High = 17 mg/l % Settlement 0 20 40 60 80 100 0 5 10 30 100 Suspended sediments (mg/l) Suspended sediments and nutrient enrichment
17. AIMS: Australia’s tropical marine research agency. www.aims.gov.au ICRS HAWAI’I 2016 2. Embryo development % Settlement 0 20 40 60 80 100 0 5 10 30 100 Suspended sediments (mg/l) Suspended sediments and temperature % Settlement 0 20 40 60 80 100 Suspended sediments (mg/l) IC50 27°C = 29 mg/l IC50 30°C = 25 mg/l IC50 32°C = 20 mg/l 27 30 32 0 5 10 30 100
18. AIMS: Australia’s tropical marine research agency. www.aims.gov.au ICRS HAWAI’I 2016 2. Embryo development % Settlement 0 20 40 60 80 100 0 5 10 30 100 Suspended sediments (mg/l) % Settlement 0 20 40 60 80 100 Suspended sediments (mg/l) 27 30 32 0 5 10 30 100 Mechanism of action: Cell rearrangement and division Suspended sediments and temperature
19. AIMS: Australia’s tropical marine research agency. www.aims.gov.au ICRS HAWAI’I 2016 0 20 40 60 80 100 27 30 32 Temperature (°C) % Settlement 4. Larval settlement 5-day old larvae exposed for 24 h to treatments 0 20 40 60 80 100 27 30 32 Temperature (°C) % Settlement 3-day old larvae exposed for 48 h to treatments 27 30 32 Mechanism of action: Changes in physiological and metabolic functions
20. AIMS: Australia’s tropical marine research agency. www.aims.gov.au ICRS HAWAI’I 2016 Great Barrier Reef (GBR) Interactions were non significant Effects of simultaneous factors were additive
21. AIMS: Australia’s tropical marine research agency. www.aims.gov.au ICRS HAWAI’I 2016 Great Barrier Reef (GBR) Worst case scenario for Acropora tenuis
22. AIMS: Australia’s tropical marine research agency. www.aims.gov.au ICRS HAWAI’I 2016 Conclusions • The effects of individual stress factors varies between early life history stages of corals. Jones et al. 2015
23. AIMS: Australia’s tropical marine research agency. www.aims.gov.au ICRS HAWAI’I 2016 Conclusions • The effects of individual stress factors varies between early life history stages of corals. • The co-occurrence of pressures can aggravate the impacts of single factors. % Fertilization 0 20 40 60 80 100 0 5 10 30 100 Suspended sediments (mg/l) 27 30 32 Fertilization threshold levels decreased with warming temperatures IC50 27°C = 37 mg l-1 IC50 30°C = 25 mg l-1 IC50 32°C = 18 mg l-1
24. AIMS: Australia’s tropical marine research agency. www.aims.gov.au ICRS HAWAI’I 2016 Conclusions • Management strategies should be directed to minimise dredging activities and improve water quality associated with river discharges during the periods of coral spawning. • The effects of individual stress factors varies between early life history stages of corals. • The co-occurrence of pressures can aggravate the impacts of single factors.
25. AIMS: Australia’s tropical marine research agency. www.aims.gov.au ICRS HAWAI’I 2016 Volunteers: Catia de Carvalho Florita Flores Marion Hliscs Heidi Luter Helios Martinez Sam Noonan Joy Smith Staff of the National Sea Simulator (AIMS Townsville) Acknowledgements A.Humanes@aims.gov.au www.adrianahumanes.com