Transcript Lecture 2 - Sites@Duke

Fall 2011
Writing 20:Ocean Acidification
September 5, 2011
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
– Biodiversity & regime shifts
• Types of studies, experiments
Physiological Processes
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•
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•
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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
– 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 acclimation
Byrne et al. 2011, Mar. Biol.
Outline
• Physiological processes
– Different types
– Acclimation and adaptation
• Ecosystem-level effects
– Ecosystem concepts
– Different types
– 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
•
•
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Tropical coral reefs
Pelagic ecosystems (pelagic = open water)
Coastal/ benthic (benthic = bottom substrate)
Deep sea
High latitude
Regime shifts
Kroeker et al. 2011 PNAS
Outline
• Physiological processes
– Different types
– Acclimation and adaptation
• Ecosystem-level effects
– Ecosystem concepts
– Different types
– Biodiversity & regime shifts
• Types of studies, experiments
http://www.whoi.edu/OCB-OA/FAQs/
http://www.pmel.noaa.gov/co2/story/Ocean+Acidification
http://oceanacidification.wordpress.com/
http://tos.org/oceanography/issues/issue_archive/22_4.html
http://www.us-ocb.org/publications/OCB_OA_rept.pdf
http://www.whoi.edu/sites/OceanAcidificationMeeting