Plankton and Their Importance in the Marine Ecosystem

Video

Types of PlanktonPhytoplankton

Zooplankton Bacterioplankton

Phytoplankton

Phytoplankton Importance

• Make up most of Earth’s biomass–Biomass = the mass of living organisms

• Phytoplankton produce about half of Earth’s oxygen through primary production

• Phytoplankton remove carbon dioxide from atmosphere

• Support the rest of the food web

Phytoplankton

Adaptations for Phytoplankton Success

• SIZE – Small is better! The smaller the cell is the easier diffusion takes place.

• Delay Sinking – Due to heavy cell walls, phytoplankton tend to sink away from the light they need. If the rate at which they sink is decreased there is a chance they may get pushed back to surface (upwelling).

Viscosity and Size

• Surface Area to Volume Ratio

Viscosity and Size

• Larger surface area to volume ratio = large surface area for frictional resistance to sinking– Good for plankton to be small

• Larger SA/V ratio also increases efficiency of nutrient uptake and waste disposal– Cube a would take up nutrients and dispose of

waste 3 times more efficiently than cube c

Decreasing the Sinking Rate• Increase friction with

horns, wings, and other cellular projections.

• Zig Zag or spiral down the water column.

• Some have gas filled floats.

https://web.duke.edu/nicholas/bio217/jrc25/impacts.html

Phytoplankton’s Preferences

• “Cold” water (species dependent)– More nutrients– More gases– Slower sinking rate– Maintain a position near surface for light

• BUT!!! Earth’s waters are warming…

http://www.giss.nasa.gov/research/news/20060925/

http://www.giss.nasa.gov/research/news/20060925/

Effects of Climate Change thus far…

• Average global temperature increase of about 1°F (0.6°C) over the past century

• Average ocean temperature increase in that time of 0.18°F (0.1°C). – Warming has occurred from the surface to a

depth of 2,300 ft (700 meters)– Majority of most marine life lives here

Cold vs. Warm Water Species

Cold Water Species• Higher viscosity waters• Floating organisms

larger• Few appendages• Slower growing – lower

rate of biological activity

• More total biomass

Warm Water Species• Lower viscosity waters• Floating organisms

smaller• Often have ornate

plumage• Faster growing – higher

rate of biological activity

• More total species

Will warming waters affect phytoplankton?

• Design a plankton and test the sinking rate in both cold and warm waters

• Write your hypothesis on data sheet

How will increasing temperatures affect phytoplankton specifically?

• Decrease in viscosity of water = increase in sinking rate

• Removal of plankton from sunlight waters• Implications in carbon cycle (land and ocean)

and oxygen production• Can plankton adapt quickly enough??