bi303 marine dynamics

learning outcomes

• what drives the dirstibution of ocean biomes/biodiversity

• how extensive is ocean biodiversity and how much do we know?

earths surface vs ocean

71% ocean, 97% of all water on earth is in the ocean

beginning of all terrestrial life

primary protein source

elements that make up living things =/= elements that make up earths crust

most common in living things are mostly soluble in saltwater, most comes from the ocean

soluble in saltwater

inside the square arent soluble, water as a sieve for elements //rewatch

marine biodiversity

lower than terrestrial biodiversity (1.5mil species richness vs 5mil) - not necessarily true, this is all the species that we know of. we know more about terrestrial organisms

mostly invertebrates, have microorganisms as well

marine biomes driven by

who is the primary producer!!

mangrove vs kelp

sort of complete each other irt the americas, mangrove located around the equator and kelp around the tropics

based on currents, upwelling, deep trench water

drivers of marine biodiversity

• temperatures

• currents and circulation

• nutrients (upwelling/downwelling)

• primary productivity

• light

• salinity

temperature

latitude based, cold at the poles, warm at the equator

graph is sea surface temperature vs amt of biodiversity * increasing diversity with increasing temperature

pinnipeds adapted to colder environments

currents and circulation

coriolis effect - wind moves clockwise in north hemi and ccw in south hemi

nutrients (upwelling/downwelling)

movement of water upwards/downwards - as water comes from land into more open ocean, deep water comes up and causes upwellings

nutrients at depth, so upwelling brings nutrients upwards while downwelling brings nutrients to deep water

primary productivity

ultimate limit on abundance and diversity

CHLOROPHYLL as a proxy of primary productivity - pigment of phytoplankton

graph of surface chlorophyll matches with areas of upwelling

light

photic zone - 0-200m

not all light penetrates down to 200m

why coastal light doesnt reach 200m - lot of stuff in the way (phytoplankton, silt, dust, more particles essentially) so it physically cant reach

salinity

less variation 32 to 38ppt

35 ppt - average

whats the most important variables for predicting marine biodiversity?

• depth

• water temp

• sunlight

whats the most important variables for predicting terrestrial biodiversity?

• sunlight

• air temp

• precipitation

(sunlight determines temperature)