BIO OCE- Phytoplankton Production - Lecture 4

what are the three ingredients of primary production

nutrients, light, and mixing

what are the main nutrients of primary production

inorganic carbon, NO3, N2, NH3, PO4, Si(OH)4, DOM, micronutrients, non limiting nutrients

what is the formula fot light

Iz = Ioe^(-kz)

when is mixing the strongest

winter due to winds

what did the north atlantic spring bloom tell us

compensation depth, first statement of spring bloom

what is the relationship between photosynthesis and photon flux

linear

where does sverdrup concept apply

subarctic/temperate North Atlantic

what are the five assumptions that sverdrup made

photosynthesis is directly proportional to irradiance, nutrients are well mixed and abundant, nutrients in perfect stoichiometic balance, light attenuation is constant, grazing losses are constant through depth

difference between compensation depth vs critical depth

critical depth where total photosynthesis in entire column equals total respiration, while compensation does respiration at a certain depth

what happens to critical depth over time

gets deeper the closer to summer due to more light penetrating deeper

when do spring blooms occur

when critical depth is deeper than the mixed layer depth

what is the smaller fall bloom caused by

grazer decline, recycling of nutrients due to grazers, stronger winds in fall and new nutrient inputs

what is the spring bloom caused by

stratification and mixing and critical depth

what nutrients and phytoplankton groups disappear first

diatoms and silicic acid leave first

what size range has the most biomass during the spring blooms

microplankton ( diatoms and dinoflagellates)

what happens to grazers in the subartic gyres

large phytoplankton accumulate because larger grazers need a minimum of 7 days to respond

what happens to grazers in the subtropical gyres

grazers on picoplankton have a 24 hour lag, so they can accumulate as much

what are some critiques to sverdrups hypothesis

north sea and arctic and Antarctic sea ice

why is the north sea a critique to sverdrups hypothesis

very shallow so there is no turbidity, blooms are seen here from seasonal light

why is the arctic and antarctic sea a critique to sverdrups hypothesis