phytoplankton Who are the Phytoplankton? Coccolithophore Diatoms Dinoflagellates
Thermocline Depth in meters 0 100 Nutrients Euphotic Zone or Mixed Layer Thermocline 0µM 5µM 10µM 200 0% 50% 100% Light 0° 10° 20° Temperature
Chl, Photos profile 0 25 50 75 100 Depth (meters) 100 10 1 0.1 0.01 % Surface Light Temperature (°C) Photosynthesis (mg C m -3 day -1 ) Chlorophyll (mg m -3 or μ g L -1 )
Gulf of Maine Data: Wilkinson and Jordan Basins Wilk. Basin Jordan Basin
Redfield Nucleic Acids Lipids Proteins Carbohydrates CO 2 Light Nutrients (N, P, etc) The Redfield Ratio 106 Carbon : 16 Nitrogen : 1 Phosphorus Liebig’s Law: Growth of a “plant” is determined by availability of the single most limiting resource.
Figure 2 . Change in chlorophyll (micrograms per liter) in coastal seawater in 4 treatments (Nitrogen and phosphorus together, N alone, P alone, and Control with no addition) over 6 days. (From Vince, S. and I. Valiela. 1973. The effects of ammonium and phosphate enrichment on chlorophyll a, pigment ratio, and species composition of phytoplankton of Vineyard Sound. Marine Biology 56: 111-134).