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Ocean Death Zone - Coggle Diagram
Ocean Death Zone
Things in the ocean that must be protected from death zone
Nutrition in the Ocean
The supply of nutrients mainly comes from:
Inland river input, sea upwelling, water mixing
vertical sea, lowering of the atmosphere, and death of marine organisms or decay of their feces.
Ocean Microbial Cycle
DOC
Bacteria
Nanoflagellates
Ciliates
Marine food web
Decomposers
Bacteria
Consumers
Herbivorous consumers
Carnivorous consumers
Primary producers
Phytoplankton, seaweed
State of hypoxia: the seawater in that ocean area has almost no oxygen
The oxygen concentration in seawater is less than 2 milliliters per liter (<2 ml/l)
The main cause of hypoxia
Human activity
Fertilizer: humans use too much fertilizer
Fertilizer enters the ocean,
Algae in the oceans will multiply
In this process, oxygen in seawater will be consumed in large quantities.
Household waste or factory waste gas
Greenhouse effect
Makes seawater temperatures rise simultaneously, causing seawater to fluctuate up and down. Unfavorable conditions, without fresh oxygen supplementation, cause hypoxic conditions
Oxygen in the ocean
The gas in the oceans comes mainly from the dissolution of the air
Factors that affect how much gas in the air can dissolve into the sea water
The temperature of the sea water
The higher the temperature, the less it can melt
Depth of water
At certain depths (between 500 and 1000
meters), the oxygen concentration will gradually increase
Location of
global ocean death zone
Almost all dead zones appear in coastal areas with relatively high population activity and some
appeared in the ocean surrounded by land.