Study your flashcards anywhere!

Download the official Cram app for free >

  • Shuffle
    Toggle On
    Toggle Off
  • Alphabetize
    Toggle On
    Toggle Off
  • Front First
    Toggle On
    Toggle Off
  • Both Sides
    Toggle On
    Toggle Off
  • Read
    Toggle On
    Toggle Off
Reading...
Front

How to study your flashcards.

Right/Left arrow keys: Navigate between flashcards.right arrow keyleft arrow key

Up/Down arrow keys: Flip the card between the front and back.down keyup key

H key: Show hint (3rd side).h key

A key: Read text to speech.a key

image

Play button

image

Play button

image

Progress

1/24

Click to flip

24 Cards in this Set

  • Front
  • Back
Depth Zones in the Ocean

Sublittoral, Bathyal, Abysmal, Hadal, Trenches
Deep Sea physical environment

Deep sea is the largest habitat. Temperature, very cold. Warmer in Mediterranean and red sea + hydrothermal vents with higher temperatures. Pressure is extremely high. Light is dark


Completely inhabitable to us.

Food availability
Nutrient Poor. Dependent on outside energy sources. Falling debris, fecal pellets, carasses
Osedax

Bone eating worms. Close relative to hydrothermal vents
Predictability

Little or no seasonal variation in temperature. Infrequent disturbances - bioturbation, benthic storms, whale falls
Deep Sea Expeditions


First. - HMS Lightning and HMS Porcupine


Dredged 4km around Britain


Challenger expedition - circumnavigated the earth and dredged upto 5.5 km depth


1960s development of modern equipment and submersibles

Deep Sea Biodiversity
Difficult to sample. Most diverse is mid deep level not the lowest for benthic invertebrates. Patchy distribution of species - richness can vary substantially. Low latitudes are more rich in species
Low Latitude Biodiversity

Many species have evolutionized to lost swim bladder and eyes
Megafauna


Echinoderms, arthropods, mollusks, fishes


Large moving or seaside7.2km depth


Lost swim bladders and negatively buoyant

Macrofauna


Smaller than megafauna, very high diversity


Polychaetes, small crustaceans, mollusks

Meiofauna


Smaller than 1mm, very diverse but still poorly known


Nematodes, copepods, ostracods, flatworms

Deep sea diversity causes hypothesis

1. Stability-time hypothesis


2. Biological Disturbances


3. Patchy food resources


4. Large Area


5. Source sink hypothesis

Stability Time Hypothesis


Constant environment causes stable biological interactions and specialization




Biological Disturbances

Predation by megafauna reduces competition among macrofauna, coexistence, Macrofauna in turn crops meiofauna
Patchy food resources

Food falls are generally patchy and can support high species diversity

Large Area

Large are should be able to support many species
Source sink hypothesis
Abundance goes up as you go deeper down. The deeper areas are sustained by the up top areas
Vent Fauna


Large variety of organisms on the vent: giant mussels bivalve, tubeworms, crab and other crustaceans


Benthopelagic


Different vent sites differ in fauna compositions

Vent Fauna Feeding

Basic energy source - chemautotrophic bacteria receive energy by oxidizing reduced suphur and other compounds. Microbial production on some vents 2-3 times


Macrofauna have evolved symbiotic relationships with bacteria.

Cold Seeps

Area were hydrocarbon, methane, hydrogen sulphide, and other fluids seep out of the ocean floor. Common in gulf of Mexico. A concern is that when the ocean is getting warmer, then these will melt and methane will be released into the ocean

Anthropogenic Impacts on the Deep Sea

Disposal, Exploitation, Ocean Acidification/Climate Change

Disposal


Sewage, Chemicals, CO2
Exploitations

Mining, Fossil Fuels
Climate

Warming temp, acidification, hypoxia