Phytoplankton and Fluorescence Matt Oliver August 18, 2014

What CONVERGE research mission question is this answering? Do areas of convergence create greater concentrations of phytoplankton that are fed on by krill?

How are these methods answering that question? By measuring chlorophyll fluorescence on a glider, we can see if higher phytoplankton concentrations are associated with convergence zones.

How do these results connect to the big picture? Higher concentrations of phytoplankton lead to the transfer of energy up the food web.

1.What are Phytoplankton? 2. What is Chlorophyll Fluorescence? 3. What does it mean to transfer energy up the food web?

What are phytoplankton? Phyto + Plankton = Plant + Drifter 1.Photosynthetic (use light to create biomass) 2.So small that they drift with the currents (0.2 – 200 microns) Thickness of 1 piece of paper is ~ 25 microns.

What are phytoplankton? Phytoplankton Taxonomy is Crazy Phytoplankton is a FUNCTIONAL DEFINITION

What are phytoplankton? DiatomsCoccolithophores Dinoflagellates

What are phytoplankton? Phyto + Plankton = Plant + Drifter Phytoplankton are recognized by what they DO. 1.Photosynthesize 2.Drift About 50% of the oxygen in your lungs came from a phytoplankton

What is Chlorophyll Fluorescence? Photosynthesize = Convert Light, Nutrients, Carbon Dioxide into Organic Matter Using the pigment called Chlorophyll Chlorophyll absorbs light (mostly blue and red) Chloroplasts are little green dots inside this phytoplankton cell

What is Chlorophyll Fluorescence? photons CO 2 Nutrients O2O2 Chloroplast Organic Matter Chlorophyll Fluorescence is extra light energy being dispersed as red photons by the chlorophyll molecule in the chloroplast. The more red light is measured, the more chlorophyll is present.

What is Chlorophyll Fluorescence? By attaching a “blue” flashing light source to the glider, we can measure the red chlorophyll fluorescence and estimate where the phytoplankton concentrations are the highest

Data What is Chlorophyll Fluorescence? We measure Chlorophyll Fluorescence at many depths as a glider moves from one location to another location.

What is Chlorophyll Fluorescence? By attaching a “blue” flashing light source to the glider, we can measure the red chlorophyll fluorescence and estimate where the phytoplankton concentrations are the highest

What is Chlorophyll Fluorescence? This isn’t Chlorophyll Fluorescence….this is Chlorophyll Reflection measured by satellites. Convergent zones appear to be concentrating phytoplankton.

Animals cannot survive on the average food in the ocean (Lasker 1975) What is the transfer of energy of the food web?

The food chains leading to tuna and humans and to sardines and humans (assuming that the trophic efficiency at each trophic level is 10%). LAST TIME

What is the transfer of energy of the food web? LAST TIME Since many organisms feed at more than one trophic level, feeding relationships in the oceans form complex food webs. This is a simplified representation of the pelagic food web of the Southern Ocean.

What is the transfer of energy of the food web? LAST TIME What are the concentration mechanisms for each trophic level? Dynamics of the fluids Animal Behavior