This site is 100% ad supported. Please add an exception to adblock for this site.

EEB 109 Marine Science Midterm 2

Terms

undefined, object
copy deck
Detritus
Matter of organic origin, but incapable of reproduction (dead)
Seston
All suspended particulate matter
Tripton
The non-living part of seston
DOM
Dissolved organic matter (passes a fine filter)
CDOM
Chromophoric (colored) DOM
Neuston
Inhabiting the surface layer
Allochthonous
Developed or originating from elsewhere
Autochthonous
Endemic: originated locally
Plankton Types
Virioplankton - viruses
Bacterioplankton - Bacteria - free living planktobacteria, epibacteria attached to larger particles
Mycoplankton - fungi
Ichthyoplankton - Planktonic fish (generally, eggs and larval stages)
Phytoplankton - photosynthetic microalgae, cyanobacteria, and prochlorophytes
Zooplankton - Heterotrophic - protozooplankton (unicellular) and metazooplankton (larval and adult crustaceans, larval fish, cnidarians...)




Autotrophic
No material of organic origin is required for growth and reproduction
Auxotrophic
Physiological requirements for one or more organic compounds, but C is obtained autotrophically.
Heterotrophic
Growth depends on organic material.
Mixotrophic
Autotrophic and heterotrophic nutrition.
Cyanobacteria
Prokaryotic, motile, with cell wall of peptidoglycan, noted for being photosynthetic, nitrogen fixers, and having gas vacuoles.
Prochlorophytes
A photosynthetic plankton with a type of chlorophyll a which is also known as chlorophyll b or zeaxanthin. it is prokaryotic, nonmotile, has a peptidoglycan cell wall, and may be the most abundant phototroph on earth. Is super small, at picoplankton size. (less than .8 micrometers)
Bacillariophyceae
a.k.a. Diatoms
Have chlorophyll a, fucoxanthin, diatoxanthin, and diadinoxanthin.
Nonmotile, except for male gametes
have cell walls made of SiO2
Have pennate and centric forms, are one of the organisms that form the spring blooms, can produce toxins.
Nanoplankton size.
Important in paleo-oceanography.
Killing sea lions along the coast? (ASP toxin, domoic acid, bioaccumulates in anchovies that the sea lions eat)






Dinophyceae
Dinoflagellates
Have chlorophyll a, c, and peridinin
Eukaryotic
Are biflagellate
Have cellulostic theca plates, if anything.
Cause red tides, are toxic in high amounts, partake in vertical migrations, produce bioluminescence (burglar alarm hypothesis), have unusual feeding mechanisms among heterotrophic representatives.
Nano plankton size.





Prymnesiophyceae/Haptophyceae
Coccolithophores
Have pigments chlorophyll a, c, and beta carotene.
Eukaryotic
some are motile
coccoliths have calcium carbonate cell wall.
Produce dimethyl sulfide
nano plankton size.
ALso have massive blooms






Ways to count and identify plankton:
- Flow cytometry - a technique for counting and sorting microscopic particles suspended in a stream of fluid by examining the physical and chemical properties of particles passing by an electronic detector.
- Examine pigment distributions - each organism will have a unique pigment signature.
- Detect DNA of harmful species with gels; can also quantify how many in a sample.
- Remote sensing - can detect photosynthesis levels from satellites.


How are phytoplankton so diverse?
- they have the basic needs, and must compete with each other for light and nutrients.
- Example of Orbulina universa
- has worldwide distribution
- used extensively in paleoceanographic reconstructions, stratigraphy
- the many morphological variants are considered a result of environmental heterogeneity. 3 unique clades. Found in different areas.
- Answer: Niche differentiation - they specialize in different growth rate, life history, motility, light, and nutritional physiology.






Determinants of r (growth rate):
Births
- Behavioral
- Fecundity
1. Intrinsic (whales vs. sea urchins ex.)
2. Environmental
1. Biotic - inter and intraspecific competition
2. Resource limitation (nutrients, habitats)
3. individual health

Deaths
- Age
- Biotic
1. predation - a function of other marine populations
2. inter-intraspecific competition
- abiotic - physiological stress from environment













Bio-limiting
Elements in seawater that become depleted in surface waters due to biological uptake. Absence limits growth. The vertical abundance curve will look like the curve of photosynthesis amount.

Examples are phosphorus, nitrogen, and silicates.

Bio-intermediate
Elements that are required for growth, may have patchy distributions, but are rarely if ever depleted.

Things like carbon dioxide. Sort of follows the photosynthetic amounts, but never drops to 0.

How are bio-limiting nutrients replenished?
- terrigenous inputs from hydrologic cycle. (this is mostly along coasts)
- Also weathering of rock nets phosphorus.
- Nitrogen fixation nets nitrogen
- thermohaline circulation - brings nutrients to surface from bottom of ocean wherever the water rises up.
- upwellings
- biological pump - biologically produced flux of carbon out of euphotic zone, which regulates atmospheric CO2. It helps determine nutrient content of deep sea, and may chance in response to changing atmospheric carbon.




Production in southern ocean is low because...
- there are high nutrient levels, but low photosynthesis levels.
- this is because Iron is limiting. Iron is critical to photosynthesis.
marine snow
a continuous shower of mostly organic detritus falling from the upper layers of the water column. Its origin lies in activities within the productive photic zone. Consequently, the prevalence of marine snow changes with seasonal fluctuations in photosynthetic activity and ocean currents.
meroplankton
organisms that spend only part of their lives in the plankton
holoplankton
organisms that spend their entire lives in the plankton
Crustaceans - copepods
- most abundant zooplankton
- life cycle from nauplii stages to copepod stage and then adults.
Most abundant animal on earth by weight.
Krill
Radiolarians
zooplankton with siliceous skeletons
form colonies up to 1 meter
capture food (bacteria, single celled plants) in mucus on spines.

cnidarians
scyphozoans
hydrozoans

have nematocysts, unique stinging cells.


mollusks
nudibranchs
pteropoda (sea angels and sea butterflies)
chaetognatha

Chordates
larvaceans
pyrosomes
salps
doliolids


compensation point/depth
depth at which the rate of photosynthesis equals the rate of respiration.
critical depth
depth at which total plant production equals total plant respiration.
Reasons for patchiness of zooplankton
- internal wave banding (internal waves pushing togehter)
- diel vertical migration
- eddy breakoffs, containing original species from that water type.
- physical concentration along a front (see langmuir cells)
- distribution of phytoplankton
- abiotic nutrients distributions, such as where upwellings are.
- tidal fronts act to concentrate plankton like langmuir cells.





Deck Info

37

sakuragasaku

permalink