Plankton and Their Importance in the Marine Ecosystem

Plankton and Their Importance in the Marine Ecosystem Video

Types of Plankton Phytoplankton Zooplankton Bacterioplankton

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. https: //web. duke. edu/nicholas/bio 217/jrc 25/ impacts. html • Some have gas filled floats.

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 ocean) and oxygen production • Can plankton adapt quickly enough? ?