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
Explain in a paragraph the rule of constant proportions.
write every time on a piece of paper
The rule of constant proportions states that the relative amounts of the various ions in seawater are always the same.
2 hydrogen atoms
1 oxygen atom
- This indicates that the oceans are chemically well mixed and that ocean salinity varies as a result of the addition or removal of pure water. So this is mainly due to precipitation/evaporation.
What are the two main tectonic plates?
- oceanic
- continental
Why does ice float and why is the bottom water of Antarctica so dense and salty?
When ice forms into solids out of cold seawater, the salt from the seawater is left behind. Ice solids are not made with the salt within them.
This is one reason it floats because the excess salt is making the surrounding seawater denser than the ice solids. This is why the bottom water of Antarctica is so salty. Large amounts of ice are formed and all the salt left behind is sinking to the bottom.
Starting from the North of NZ and moving South, name the biogeographic zones discussed in class.
- three kings
- north eastern
- central
- southern
- fiordland
- sub-antarctic
- chathams
- kermadecs
What is marine biogeography?
Marine biogeography is the study of marine species and the geographic distribution of their habitat and the relationship between them and the environment.
List all the adaptations you can think of, of species living in the abyssal zone.
- Big mouth and jaw
- Big stomach
- Bioluminescent for prey
- Swim bladders for buoyancy
- Well developed muscles for long-distance swims
- Large eyes - the pigment in eyes
Explain what the hydrothermal vent ecosystem is and its food chain and processes.
Hydrothermal vents are openings in the seafloor where water enters and exits and is superheated and enriched with metals and minerals from the underlying bedrock. They are an example of an ecosystem-based on chemosynthesis, where life is sustained by energy from chemicals rather than energy from sunlight.
Food chain:
- Chemicals and minerals from the earth
- Primary producers - Bacteria - symbiotic and vent
- Primary producers - Zooplankton, Worms, Clams + mussels
- First-order carnivores
- Top-order carnivores
Describe the marine biology of the Fiords. (deep water emergence)
- long narrow bodies of water along coasts of glaciated areas.
- glaciers along the coast eroded deep sharp canyons
- Fjords were created after the glaciers melted and the canyons were flooded by rising sea levels
- these marine ecosystems are typically surrounded by tall mountains with steep sides that continue below the waterline.
- *These unique systems allow deep-sea organisms to live close to shore, even somewhat inland, a fact that is abnormal or impossible along typical coasts. Deep-water coral reefs are also often found in fjords. Most coral reefs are tropical and occur in shallow, clear water.
Give an example of a keystone predator and discuss the effects of this predator on its environment.
Every ecosystem has certain species that are critical to the survival of the other species in the system.
Sharks are the classic top predators of marine ecosystems. As a keystone species, their presence along island coastlines has been linked to greater overall fish diversity.
Explain how ocean surface currents are formed?
clues: equator sun heat Ekman spiral Coriolis effect pressure
Surface currents are formed by global wind patterns and forces of the earth’s rotation.
- Ocean surface currents are caused by global wind systems fueled by the energy of the sun. Surface pattern currents are determined by wind direction - Coriolis force. They can create upwellings that create deep water currents. Ekman spiral. Coriolis effect 45 deg with every depth.
Explain the one ocean concept and how humans have an impact on it.
All of the oceans and seas on Earth are interconnected making one world ocean. Humans impact the world’s ocean through pollution, physical modification to beaches, rivers shores, overfishing etc..
What drives tectonic plate movement/motion? Is there any evidence to back this up?
Tectonic plates are broken pieces of the earth’s crust and mantle. Their movement is caused by convection currents and because they sit on top of fluid magma.
Hermatypic corals
Reef-building
Adaptations of arctic animals
- Antifreeze
- thinner blood
- low metabolic rates
List NZ’s sub-antarctic islands (5)
A A B C S
- Antipodes Islands
- Auckland Islands
- Bounty Islands
- Campbell Islands
- Snares Islands / Tini Heke
Describe the relationship between corals and zooxanthellae
mutual endosymbiotic relationship
- both receive positive benefits from it
What are the benefits of endosymbiosis between corals and zooxanthellae?
Zooxanthellae:
- stable protected home
- exposure to sunlight
- nutrients (N&P)
Coral polyp:
- Direct nutrient source (photosynthesis)
- Enhanced capacity to calcify
- Enhanced capacity to remove metabolic wastes
- Enhanced capacity to recycle N&P
List 3 major differences between terrestrial and marine systems that we have discussed in class.
- Water
- 800x denser than air (little energy cost) - Land organisms
- tissue much denser than the surrounding environment (to counter gravity). - Productivity
circular wavefronts are formed when the wavelength is _______ than or equal to the gap in a barrier.
Greater
Three wind-related factors determine the size of waves generated, state what they are, and explain them:
- Fetch - span and water over which the wind
blows, duration - Duration = time that wind has been blowing
- Speed = force of the wind
What are gyres in the ocean? How do you think they are formed?
Gyres are large circulation rotations of water within a basin that is wind-driven.
- global wind patterns
- Coriolis force
What are the three basic habitats of the ocean?
- water column
- soft bottom
- rocky bottom
What are some features of the deep?
- beneath 200m
- below the level of light penetration (below photic zone)
- No plants or phytoplankton (no photosynthesis)
- Marine snow for feeding (Detritus)
List the important factors when defining the deep.
- pressure (atmospheres)
- Temperature
- No light
- Limited oxygen
- Special adaptations
Where does upwelling occur?
Along coastlines.
What is upwelling?
The movement of deep, cold, nutrient-rich water brought up to the surface.
Why is upwelling important?
Because it brings nutrient-rich water to the surface which sustains life.
What happens when surface currents meet?
They are deflected (change paths)
Ocean currents move energy in the form of?
Heat
Where do the ocean’s warm water currents originate from and where do they travel?
- Equator 2. The poles
What causes surface currents north and south of the equator to move in different directions?
The rotation of the earth.
True or False?
Near the equator, the winds blow ocean water east to west?
True!
winds blow ocean water west to east near the poles
What is the Coriolis effect?
The apparent curving of moving objects from a straight path due to the earth’s rotation.
What three factors work together to form a pattern of surface currents on earth.
- Global winds
- Coriolis effect
- Continental deflections
Surface currents always move water in which directions?
Horizontally
Ocean currents have an effect on what two things?
- Climate
2. Weather
How do warm water currents affect coastal areas in which they flow?
Warm the coasts
What is a tide?
Tides are long-period waves that move through the oceans in response to the forces of the moon and sun.
- Tides originate in the oceans and progress toward the coastlines
Why are tides ecologically important?
- Create habitats (intertidal zone)
- Mix upper water layer, nutrients and oxygen
- Provide food for sedentary organisms
- Disperse juvenile larval stages of marine organisms
- Disperse pollutants from run-off
Twin bulges in the planets water envelope are due to which two factors?
- Inertia
2. Moon (gravitational attraction)
What is the result of solar and lunar tides working synergistically together?
They create spring and neap tides.
Spring tides = The highest high and lowest low tides.
Neap tides = The lowest high and highest low tides.
What are some reasons tides vary locally and globally?
think about movement of earth the different forces pressure winds etc..
- Moon and sun
- Spring and neap tides
- Seasonal variation
- Coriolis effect
- Depth (bathymetry)
- Low pressure
- Onshore winds
What happens at aphidromic points or nodes in the ocean?
Amphidromic points = no tides at the node, but increasing tide with distance from node.
Semidiurnal tides
2 high tides and 2 low tides per day
Diurnal tides
1 high tide and 1 low tide per day
Mixed semidiurnal tides
2 high and 2 low of different sizes each day
List the North Hemisphere differences to South Hemisphere
- North of the equator (above)
- Pollution is higher in n/h (links with human population)
- More landmass, less water
- Around 90% of human population in n/h
- Storm movement (Coriolis effect)
- hurricanes and tropical storms rotate clockwise in the n/h (Deflection)
This affects the movement of water and atmospheric air/winds, which can greatly affect regular weather and climate conditions.
Atmospheric circulation
Temperature differences between land and sea create pressure gradients.
- Land and Sea breezes
- Low pressure when air is rising
- High pressure when air is falling
Global circulation caused by?
temperature changes in air masses.
Wind direction in relation to ocean currents (atmospheric circulation)
Wind direction is labelled from the bearing that it originates from. Wind blows from high too low pressure.
- Eg, westerly wind comes from the west
Thermohaline circulation
what is it?
where does it originate from?
what are some effects of thermohaline circulation?
Thermohaline circulation begins in Earth’s polar regions.
- when ocean water gets very cold in these areas,
- Sea ice forms
- Surrounding seawater gets saltier, (because when sea ice is formed, the salt is left behind) - effect
- Increases in density and sinks.
Thermohaline is that layer of more dense, saltier body of water that is below the surface layer(s).
Explain how the Ekman spiral works?
Wind blowing over the water creates a surface current 45 deg offset from the wind.
Each successive layer of water is moved and deflected by the layer above, creating a spiraling pattern of water movement that diminishes with depth.
- all movement in the n/h will move 45 deg to the right and left in the s/h 45 deg.
Describe two ways that upwelling can happen?
- Wind blowing across the surface layer
2. Deepwater currents hit an underwater obstruction
What are the three physical properties of water?
- Liquid
- Solid
- Gas
