Spring 2012 Writing 20:Ocean Acidification
January 19, 2012
Lecture 2“Physiological and Ecosystem Effects of Ocean Acidification:
Potential Direct and Indirect Effects
Some of this lecture obtained from http://aslo.org/lectures/11_005/11_005_rfeely_sdoney.html
Outline• Physiological processes
– Different types– Acclimation and adaptation
• Ecosystem-level effects– Ecosystem concepts– Different types of ecosystems– Trophic cascades– Biodiversity & regime shifts
• Types of studies, experiments
Physiological Processes
• Calcification• Photosynthesis• Hypercapnia (too much CO2 in blood)
• Nutrient uptake and limitation• Reduced gene expression• Sensory perception
Physiological Processes
• Calcification• Photosynthesis• Hypercapnia (too much CO2 in blood)
• Nutrient uptake and limitation• Reduced gene expression• Sensory perception
Photosynthesis
• Two different species of algae
• OA could lead to shifts in algal species composition
Physiological Processes
• Calcification• Photosynthesis• Hypercapnia (too much CO2 in blood)
• Nutrient uptake and limitation• Reduced gene expression• Sensory perception
Sensory perception
Outline
• Physiological processes– Different types– Acclimation and adaptation
• Ecosystem-level effects– Ecosystem concepts– Different types of ecosystems– Trophic cascades – Biodiversity & regime shifts
• Types of studies, experiments
Acclimation means the ability of an organism to change its phenotype, or expressed trait so that it can survive in an environment as it changes.
Adaptation means the ability of a population of organisms to change its genotype, or its genes in the DNA, over successive generations (evolution).
- generation times are important- genetic diversity is important
Example of possible acclimationB
yrne et al. 2011, Mar. B
iol.
Outline
• Physiological processes– Different types– Acclimation and adaptation
• Ecosystem-level effects– Ecosystem concepts– Different types of ecosystems– Trophic cascades– Biodiversity & regime shifts
• Types of studies, experiments
Ecosystem
• Definition: A spatial explicit unit of Earth where living things and the environment interact
• Perturbations (like ocean acidification) can have various direct and indirect effects:– Shifts in species composition and trophic cascade (food
web) effects– Temporal and spatial shifts in ecosystem functions– All of these can change the structure, energy flow, and
other functions of the ecosystem => regime shift
Different Types of Ecosystems Likely to be Affected by OA
• Tropical coral reefs• Pelagic ecosystems (pelagic = open water)• Coastal/ benthic (benthic = bottom substrate)• Deep sea• High latitude
Outline
• Physiological processes– Different types– Acclimation and adaptation
• Ecosystem-level effects– Ecosystem concepts– Different types of ecosystems– Trophic cascades– Biodiversity & regime shifts
• Types of studies, experiments
Outline
• Physiological processes– Different types– Acclimation and adaptation
• Ecosystem-level effects– Ecosystem concepts– Different types of ecosystems– Trophic cascades– Biodiversity & regime shifts
• Types of studies, experiments
Regime shifts
Kroeker et al. 2011 PNAS
Outline
• Physiological processes– Different types– Acclimation and adaptation
• Ecosystem-level effects– Ecosystem concepts– Different types of ecosystems– Trophic cascades– Biodiversity & regime shifts
• Types of studies, experiments
http://www.pmel.noaa.gov/co2/story/Ocean+Acidification
http://www.whoi.edu/OCB-OA/FAQs/
http://oceanacidification.wordpress.com/
http://www.us-ocb.org/publications/OCB_OA_rept.pdf
http://www.whoi.edu/sites/OceanAcidificationMeeting
http://tos.org/oceanography/issues/issue_archive/22_4.html