Primary productivity
Energy transfer
The rate at which solar energy is stored in organic matter
Primary productivity turns solar energy into available
chemical energy
Primary productivity
Factors affecting primary productivity:
Nutrients
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Factors affecting primary productivity:
Nutrients
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Nitrates
Phosphates
Iron
Silica
Nitrates
Phosphates
Iron
Silica
Factors affecting primary productivity:
Nutrients
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Nitrates
Phosphates
Iron
Silica
Simplified: Deep, cold
water has the most
nutrients because
that’s where all the
dead stuff has fallen
and is decomposing
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Factors affecting primary productivity:
Nutrients
Temperature
profile
Factors affecting primary productivity:
Nutrients
Temperature
profile
Abundant nutrients
• Upwelling
• River runoff
• Isothermal
Typical water column
Factors affecting primary productivity:
Solar radiation
• Blue wavelengths
penetrate deepest
• Longer wavelengths
absorbed first
Typical water column
Factors affecting primary productivity
Nutrients
Solar radiation
• Upwelling
• River runoff
• Isothermal
• Top 100 m
• At 100 m, only 1% of
solar radiation that falls
on the surface
Photosynthesizing marine organisms
Photosynthesizing marine organisms
1. Seagrasses
2. Macroscopic algae
3. Microscopic algae
4. Photosynthetic bacteria
1. Seagrasses
Phylum: Anthophyta
Eelgrass (Zostera marina)
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Photosynthesizing marine organisms
Photosynthesizing marine organisms
2. Macroscopic algae
2. Macroscopic algae
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Brown algae
Green algae
Red algae
Brown algae
Green algae
Red algae
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Macrocystis – grows up to 60 m long
Ulva
Ulva
Photosynthesizing marine organisms
Photosynthesizing marine organisms
2. Macroscopic algae
3. Microscopic algae
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Brown algae
Green algae
Red algae
Golden algae
• Diatoms (SiO2)
• Coccolithophores (CaCO3 )
Dinoflagellates
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Produce food for 99% of marine animals
Regional primary productivity
Factors:
Nutrients
Solar radiation
Regional primary productivity:
Tropical regions
• Solar radiation: strong year round
• Nutrients: Strong thermocline isolates
nutrients in deep water
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Regional primary productivity:
Tropical regions
Regional primary productivity:
Polar regions
• Low rate of primary productivity
• But . . . high primary productivity in areas of
• Solar radiation: seasonally limited
• Equatorial upwelling
• Coastal upwelling
• Coral reefs
• Nutrients: Abundant
- Isothermal
- S. hemisphere: upwelling of
North Atlantic Deep Water
around Antarctica
Regional primary productivity:
Temperate regions
• Solar radiation: seasonal
• Nutrients: seasonal
Biomass Pyramid
Zooplankton
• Heterotrophic
• Adaptations to increase buoyancy
• Internal rigid gas container
• Oil droplet
• Gelatinous bodies
Nautilus
Moon jellyfish
London University
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Zooplankton
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Zooplankton
Microscopic
- Radiolarians (30 µm - 2 mm)
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Foraminifers
Copepods
Macroscopic
- Krill
- Hydrozoan
- Scyphozoan
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Microscopic
- Radiolarians
- Foraminifera (100 µm - 20 cm)
- Copepods
Macroscopic
- Krill
- Hydrozoan
- Scyphozoan
Reticulopodia to catch food
London University
Zooplankton
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UCMP Berkely/London University
Zooplankton
Microscopic
- Radiolarians
- Foraminifera
- Copepods (0.5 mm - 15 cm)
Macroscopic
- Krill
- Hydrozoan
- Scyphozoan
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Microscopic
- Radiolarians
- Foraminifera
- Copepods
Macroscopic
- Krill (euphausiids)
- Hydrozoan
- Scyphozoan
Source: Uwe Kils
Zooplankton
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Microscopic
- Radiolarians
- Foraminifera
- Copepods
Macroscopic
- Krill
- Hydrozoan
- Scyphozoan
Photo: George Mobley
Zooplankton
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Water Jelly
Photo: OSF
Microscopic
- Radiolarians
- Foraminifera
- Copepods
Macroscopic
- Krill
- Hydrozoan
- Scyphozoan
Photo: David Doubilet
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Pelagic marine life
Trophic levels
Biomass pyramid
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