Marine Science and Ecology Terms and Definitions (Exam Prep) Flashcards
Coriolis effect
The effect of Earth’s rotation on the direction of winds and currents.
Coriolis deflection
The apparent deflection of objects moving across Earth’s surface to the right of the direction of travel in the Northern Hemisphere and to the left of the direction of travel in the Southern Hemisphere. 45 degrees left or right. Caused by Coriolis force.
Ekman spiral
Surface winds drive surface currents, and each layer of water drags the layer below, but the Coriolis Force changes each layer’s direction slightly to make a spiral effect.
Coriolis force
The apparent force, resulting from the rotation of the Earth, that deflects air or water movement.
Downwelling
The movement of water from the surface to greater depths.
Due to: - Density - Temperature - Salinity of the seawater.
Upwelling
The process in which deep, cold and nutrient-rich water rises toward the surface.
What is thermohaline circulation?
Thermo = heat Haline = salinity
A water circulation produced by differences in temperature and/or salinity (and therefore density)
Surface currents
Ocean currents on the top of the water that are driven by wind.
Thermocline
A steep temperature gradient in a body of water such as a lake, marked by a layer above and below which the water is at different temperatures.
Pycnocline
Middle layer of the ocean. Change in density.
Nekton
Free-swimming animals that can move throughout the water column
Benthos
Organisms that live attached to or near the ocean floor
Biogeography
Geographic distribution of species.
Habitat is a huge factor for where species live.
- Environmental conditions
Abiotic
Non-living
- sunlight
- temperature
- air
- soil
- water
- salinity
- PH
- minerals
Biotic
Living
- animals
- plants
- bacteria
- fungi
- protists
- archaea
Biogeography is a sentence form.
Biogeography is the study of the geographic distribution of animals, plants, and other forms of life.
It considers the factors responsible for the variations in distribution and habitat patterns.
What is deep water emergence? and
What causes it?
- When a deep-sea species inhabits depths shallower than its usual distribution.
- Freshwater layer on the surface that is stained with tannins
Is the East Auckland Current (EAC) northerly or southerly?
Southerly
What is the freezing point of seawater?
-1.9 degrees celcius
What is the average salinity of the ocean?
35 PSU
What does PSU stand for?
Practical salinity units
What are the three plate tectonic boundaries?
- Divergent
- Convergent
- Transform
What are the main stress factors on animals living on the rocky shore?
- overheating
- desiccation
- cold temperatures
- wave shock
What are some adaptations that organisms use to avoid desiccation?
- Cats eye double door operculum is sealed with mucus
- Limpets clumping together
- This behavior retains moisture. They also clamp down and seal gaps with mucus.
- Shell colour
- Lighter shells are better for extreme temps as they can reflect light.
The major currents in ocean gyres can affect ocean temperatures and marine ecology.
What are some examples?
- Rare species in areas where they wouldn’t usually be if not for gyres, currents and wind, etc..
- The Humboldt current (Galapagos)
2. Gulf stream
What drives the Ekman transport of water away from the coast. What can this cause?
- Coriolis effect & Persistent wind
- upwelling
What are New Zealand’s main currents?
- east cape current
- east auckland current
- west auckland current
- Southland current
- westland current
Define ‘ecological niche’
The Grinnellian niche concept embodies the idea that the niche of a species is determined by the ecological role and space that an organism fills in an ecosystem.
The role of an organism in an ecosystem.
What are the three types of adaptations?
- behavioral
- structurual
- functional/physiological
What are the four main population controls?
- Mortality
- Natality
- Immigration
- Emigration
In relation to population growth, give two reasons why it may start to slow down (Stationary, slow stage).
- Old age
2.
Survivorship
Give an example for high survivorship - low survivorship and low survivorship - high survivorship.
- High - Low = Humans
2. Species of crayfish
Why does ice float and why is this ecologically important?
- Because the surrounding water is denser than the forming ice due to hydrogen bonds keeping the water molecules farther apart in ice, making ice less dense.
- If the hydrogen bonds were firmly compacted, ice would be denser and sink which is bad because floating ice is very important. - Floating ice is very important biologically as it acts as an insulator stopping further cooling, otherwise, ice would sink and start at the bottom first and freeze the coldest parts of the oceans.
What are the two most dissolved salts in the ocean?
Sodium chloride (NaCI)
What is the average PH of the ocean?
7.8
What are some factors that affect the sea levels.
- tides, winds, and changes in barometric pressure
- global temperatures
- global warming
- melting glaciers
- land movement & changes
- salinity changes