For Final Exam Flashcards
What is Biogenic ooze made of?
Inedible shell and skeletal material (calcium carbonate material)
Marine snow
Rain of poop and dead matter that descends to the deep
What percent of surface production reaches the deep?
1-3%
Disturbance definition
Any discrete event that disrupts ecosystem structure, community, or population structure. Can include storms, disease, waves, heat waves, ice formation, climate change.
What is not disturbance
Herbivory, predation, other normal things that occur in a ecosystem
Abyssal plain
Vast, featureless area of the deep ocean floor characterized by gentle slopes and fine sediments typically located beyond continental margins
Hadal zone
Deepest benthic habitat typically found in ocean trenches (6000m to 11000m)
How much more biomass does deep sea hot spots have compared to the rest of the deep?
10^5 -10^6
3 different types of deep sea hot spots
Hydrothermal vents
Cold seeps
Whale falls
Why do deep sea hot spots ‘hot spots’ have more biomass than the rest of the deep?
They have an influx of organic matter that is absent elsewhere in the deep sea
Chemosynthesis
Using energy-bearing inorganic chemicals (3 examples of these) to power conversion of C02 to organic matter
- usually facilitated by bacteria
3 examples of energy bearing inorganic compounds
Hydrogen sulfide - H2S
Methane - CH4
Ammonia - NH3
Where do energy bearing inorganic compounds come from
- geothermally driven reactions beneath the sea bed
-hydrocarbon (methane) seeps are actually derived from past photosynthetic production
What makes a cold seeps?
Methane (CH4) seeping out of the seafloor
Methane hydrates
Crystallized methane that encrusts the seafloor
Are cold seeps associated with geothermal activity?
Nope
Where are cold seeps common?
Gulf of Mexico
What is a whale fall?
A fallen whale (no shit)
What are the three decomposition stages of a whale fall?
- Mobile scavenger stage
- Enrichment - opportunist stage
- Sulfophilic stage
What is the time frame for each of the three decomposition stages for a whale fall?
- Mobile scavenger stage - months to a few years
- Enrichment - opportunitst stage - months to a few years
- Sulfophilic stage - decades
Mobile scavenger stage
Organisms such as sharks, hagfish, rattails feed on soft tissues
Months - years
Enrichment-opportunist stage
Worms, crustaceans, and mollusks colonize the bones and surrounding sediment
Months - a few years
Sulfophilic stage
Mussels, clams, and snails rely on bacteria to break down lipids in whale bones, releasing H2S. Chemosynthetic bacteria use that to form the most diverse deep sea communities ever recorded (up to 190 visual species on a single skeleton)
Decades
Ecological succession
Process by which mix of species and habitats in area change over time. Communities replace eachother until a climax community is reached.
