World of Ecology
Ocean ZonesStudent Research
Students researched the distinct properties of an ocean zone including depth, light (or lack thereof), pressure, flora, fauna, sources of food/energy, human activity/intrusion.
Ocean Zone Layers
The Bathypelagic Zone
Research and Content provided by Northwestern students Abraham Deitz-Green & Liam Jeninga
Fast Facts:
- Depth: ~1,000-3,000m
- Light: No access to sunlight
- Pressure: 100-300 atmospheres
- Temperature: ~4°C (39°F)
Animal Life:
- Generally: fish, mollusks, crustaceans, and jellyfish
- Fish have tiny eyes, fragile skin, faint muscles, and slimy bodies
- Sperm Whales on occasion to hunt giant squid
- The most common Mullusk is the Vampire Squid
- Plant life: No plant life. No phytoplankton.
Sources of Energy:
- Nutrients come from debris and waste of upper ocean layers (epipelagic horizon)
- Thermohaline Circulation (ocean currents caused by temperature and salinity)
- Distributes oxygen, nutrients, and carbon energy from the surface
- Sourced in the Weddel Sea (Southern Hemisphere) and the North Atlantic Ocean (Northern Hemisphere)
- Zooplankton migrate into the Bathypelagic zone during the day
Implication of the Anthropocene:
- The Bathypelagic zone contains a large amount of carbon and is an important moderator of anthropogenic climate change
- High rates of remineralization!
The Abyssopelagic Zone
Research and Content provided by Northwestern student Nicholas Hollenbeck
Fast Facts:
- Depth: ~3,000-6,500m
- Light: No access to sunlight
- Pressure: up to 750 atmospheres
- Temperature: <3°C (37°F)
Animal Life:
- Relies on marine snow/whale falls
- Either adapted to stay out of oxygen-depleted water above or to still extract oxygen from higher up
- Some animals move between abyssal and bathyal zone
Sources of Energy:
- No plants
- Nutrients come from debris and waste of upper ocean layers
Implication of the Anthropocene:
- 1/3 of the planet’s seafloor
- Abundance of important minerals in manufacturing
- Cobalt
- Nickel
- Aluminum
- Manganese
The Hadal Zone
Research and Content provided by Northwestern students Kaitlyn Fields & Maggie McKenna
Fast Facts:
- Depth: ~6,000-11,000m
- Light: No access to sunlight
- Pressure: >545 atmospheres
- Temperature: ~0°C (32°F)
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Animal Life:
- Very few species are able to survive the pressure and lack of light/food in the Hadal zone, but here are a few:
- Amphipods: Most common creatures in the Hadal. Crustaceans that look kinda like big fleas. They are the bottom of the food chain and most important food source to other creatures of the Hadal.
- Cusk-Eel: The eel who is not an eel but rather a fish. These fish can be found from the Epipelagic down to the Hadal, so they have a wide range of pressures and temperatures that they are able to survive. They have gooey translucent skin and non-functional eyes, but have evolved “sensory pores”.
- Snailfish: These are the most dominant fish found in the Hadal and are the deepest living fish ever recorded. Like the cusk-eel, they have gooey translucent skin and you are able to see the organs of this fish. Whereas the cusk-eel evolved to have extra bones to help stabilize their structure in the pressure, snailfish evolved to have cartilage instead of bone. They have the most extreme depth range of all marine fish. The snailfish and the cusk-eel are the only two fish that live below 8000 meters.
- Rat-Tail Fish: They have a tadpole like body. They have developed a more advanced lateral line which is a special sensory organ that aids them where they cannot see. They move very slowly to conserve energy while they hunt for food on the ocean floor.
Sources of Energy:
- The bottom of the food chain, amphipods, survive on eating detritus, which is the decaying matter of animals and plants that float down from above.
- Most other of the fish then eat the amphipods, or other species in the Hadal smaller than them.
- There is evidence of some single cell organisms gathering energy through chemosynthesis in the hydrovents of the Hadal.
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Implication of the Anthropocene:
- Two sampling campaigns in the 1950s: the Danish Galathea and the Soviet Vitjaz expeditions. These exploratory campaigns provided an initial catalog of Hadal species.
- Physiological processes in Hadal animals hold promise for developing new drugs and treatments for medical conditions such as Alzheimer’s disease.
- Hadal systems remain among the most poorly explored habitats on Earth.
- The most widely known patch of Hadal seafloor is Challenger Deep in the Mariana Trench, the deepest known spot on Earth.
- Some unmanned underwater vehicles capable of reaching full-ocean depth completed sampling and observation missions.
- Some crewed dives in Hadal region.
Research Links:
