BIOPHYSICAL INTERACTIONS & CORAL REEFS

Question 1

Atmosphere

Answer 1

blanket of gases surrounding Earth to provide air to breather and protection from heat and radiation

Question 2

Lithosphere

Answer 2

Earth’s solid outer shell; the topography of the land

Question 3

Biosphere

Answer 3

Earth’s surface zone which contains all living creatures and plants

Question 4

Hydrosphere

Answer 4

the interconnecting system of water storage in the lithosphere, atmosphere and biosphere

Question 5

Ecosystem

Answer 5

interaction between living and non-living elements operating in dynamic equilibrium

dynamic equilibrium: constantly changing and adapting to change to reach

Question 6

Troposphere

Answer 6

• layer closest to earth
• with increased altitude, air temp. and air pressure drop
• contains all water vapour and dust in atmosphere
• clouds and weather patterns formed

Question 7

Climate

Answer 7

patterns of temperature, precipitation, etc

Question 8

Weather

Answer 8

daily changes in atmospheric conditions

Question 9

Factors for global variation in climate

Answer 9

• variation in sunlight insolation: sun energy most direct, concentrated and consistent near the equator
• rotation on axis –> day and night, revolution around sun –> seasons, tilt of earth means some areas will always get more sunlight than others
• composition of atmosphere (greenhouse gases absorbing heat, volcanic eruptions, water vapour)
• distribution of continents and oceans: warm vs cold currents, proximity to ocean
• topography: mountain ranges greating orographic rainfall and rain shadows

Question 10

Human impacts on atmosphere

Answer 10

• CO2 emmisions from cars, factories, households, etc. –> enhanced greenhouse effect and global warming
• acid rain from sulphuric and nitric acid from factories: wet –> acid deposition in rain, fog, snow, etc., dry –> acidic gases and dust eat into sandstone, buildings, cars, etc.
• CFCs deteriorating ozone layer (Aus & Antarc.) –> layer of protection from UV rays removed –> Aus highest rate of skin cancer in world

Question 11

Convectional rainfall

Answer 11

energy of sun hits Earth’s surface –> evaporates water –> warm moist air rises and cools –> condenses into clouds –> water droplets form precipitation as weight of clouds grow

lasts for a short period of time, mainly close to the tropics

Question 12

Orographic rainfall

Answer 12

warm, moist air travels up mt. on windward side (changes temp. and pressure) –> condenses into water vapour and forms cumulus clouds (rain & thunder) –> dry air descends on other side of mt., rain shadow

influenced by ocean currents

Question 13

Coastal change processes

Answer 13

• Hydraulic action: waves hit rocks and traps air, rocks to crack overtime
• Abrasion: small pebbles and sand rub against base of cliffs to smooth and erode using friction
• Attrition: broken pieces of rock collide to break down into smaller sediments
• Solution: acids in water dissolves rocks (limestone)

Question 14

Cold ocean currents

Answer 14

• originates from Arctic and Antarctic circles
• mainly on west coast of continents
• rich in oxygen and marine life
• Humboldt Current: rich in anchovies, west coast of N and S America, created Atacama Desert
• west coast of Aus: tuna

Question 15

Warm ocean currents

Answer 15

• creates coral reefs (GBR)
• east coast of continents
• influences the south due to climate change - El Nino and El Nina

Question 16

Human impacts on the hydrosphere

Answer 16

• industrial runoff: agricultural –> fertilisers and herbicides: phosphates, nitrates, petrochemicals, silt –> carries nutrients and allows crops to grow, but pollutes water: sedimentation dries out waterways, excess blue green algae reduce O2 for animals, excess mercury bioaccumulation
• overfishing: resource depletion, ecosystem imbalance, aquatic pollution
• dams: reduce waterflow and disrupts natural waterways, cold water pollution, vertical stratification, straightens river (faster flowing, frequent and severe floods)

Question 17

Tectonic plates

Answer 17

• moves via convection currents in the magma in the mantle
• divergent: moves apart, forms mountain ridges, volcanic activity (Iceland)
• convergent: subduction, destructive, forms trenches, volcanic activity (Himalayas)
• transform: sliding, conservative, no formations or volcanic activity
• most active: Ring of Fire (Hawaii - island hotspots, fertile soil)

Question 18

Human impacts on lithosphere

Answer 18

• deforestation –> erosion –> weak water banks –> flooding –> plants and animals displaced
• mining
• runoff and waste increases acidity and destroys soil quality
• CO2 emissions –> chemical weathering and erosion

Question 19

Global vegetation patterns

Answer 19

• climate (precipitation, temperature, light, wind)
• topography (slope, aspect, altitude (1km up = 6.5 degrees colder))
• edaphic (changes soil acidity, mineral content, texture colour etc)
• biotic (plant competition, animal relationships)

Question 20

Human impacts on biosphere

Answer 20

• deforestation: destroys habitats, food chains, ecosystems, etc.

Question 21

Coral polyps and zooxanthallae

Answer 21

• symbiotic / mutualistic relationship
• polyps: small animal that secretes hard outer shell of limestone that attaches to rock or dead polyps –> gives algae protection, CO2 and nutrients for photosynthesis
• zooxanthallae: lives inside coral polyps –> gives coral oxygen, carbohydrates, bright colour, waste removal
• coral polyps expel zooxanthellae if temp. exceeds 29 to conserve energy to photosynthesise –> coral bleaching –> coral dies if occurs for over a month

Question 22

Benefits of coral reefs

Answer 22

• biodiversity: 25% of ocean’s fish depends on healthy coral reefs
• protects coastlines from storms and erosion
• provides tourism, jobs, recreation
• cultural value

Question 23

Coral ideal growth and function

Answer 23

• depth: 35m
• temp.: 26 deg. (bleaches above 31)
• high solar radiation for photosynthesis
• low nutrient water to maintain low algae growth
• saline water
• circulating water

Question 24

Location of coral reefs

Answer 24

• tropical waters near equator - Indo-Pacific region (GBR) has 91.9% of world’s coral reefs
• Australia: GBR (high biodiversity, good managment / developed country)
• Phillipines (2nd largest reef but high dynamite and cyanide fishing –> killing coral and fish, bioaccumulation)
• Fiji (2/3 at risk from overfishing, coastal development, logging, and erosion)
• St Kitts (black line algae: semi and untreated human waste, stop photosynthesis, developing country)

Question 25

Developing countries and coral reefs

Answer 25

* Coral reefs are mainly found in developing countries * low income --> lack of food --> exploitation of fish * making money from the reefs --> destruction of coral * slums with poor sewerage and waste systems --> algae blooms, sunlight is blocked, kills coral * lack of government control, funding, and protection * coastal development for large amounts of tourism leads to erosion and silt / sedimentation

Question 26

Types of coral reefs

Answer 26

* fringing: along coast, shallow water * barrier: paraller to shore but separated by lagoon or body of water * atoll: ring shaped surrounding undersea volcano that rose to the surface * patch: isolated patches that vary in size and grow from the bottom of continental shelves * cays: spit of sand

Question 27

Hard coral

Answer 27

* Elkhorn: Caribbean, can grow up to 3.7m long and 1.8m high, groups called thickets, habitat for marine animals e.g. Caribbean Reef Octopus, threatened by white band disease, climate change, pollution, unsustainable fishing * Open brain coral: threatened due to use for home fish tanks, many fluro colours, Indo-Pacific

Question 28

Soft coral

Answer 28

* Xenia coral: fastest growing soft coral, unique: uses "hands" to "pulse" water away, found in shallow seas under bright light and mid to high tide * Nepthea coral: branching with very fine polyps, flexible structure, Indo-Pacific (Fiji, Solomon Islands)

Question 29

Human impacts on GBR

Answer 29

* climate change --> ocean warming --> coral bleaching * tropical cyclones: (naturally good for upwelling cold water, reducing coral bleaching, allowing new growth), strong winds --> rough seas --> breakage, rain --> reduced salinity --> increases runoff and sedimentation * COTS: occur naturally but outbreaks occur: run off, overfishing, global warming * pollution and water quality: overgrazing, erosion, chemical agricultural runoff --> eutrophication: oxygen supply is limited, so phytoplankton thrives which COTS larvae consumes and grows

Question 30

Impacts of deforestation

Answer 30

* hydrosphere: increased ocean acidity due to excess CO2 in waterways and carbon sinks --> kills minerals and alters marine life food chains * atmosphere: CO2 emissions --> enhanced greenhouse effect --> warming of earth and atmosphere * lithosphere: damages land + no vegetation --> erosion * biosphere: loss of biodiversity, habitats

Question 31

Impacts of agricultural and industrial runoff

Answer 31

* hydrosphere: silt and sedimentation from farming and pest/herbicides polluting waterways --> change of depth, blue green alage * atmosphere: dry acid rain (gases and dust carried by wind breaks down sandstone, buildings, cars, etc.) * lithosphere: chemical and physical erosion, degradation of soil quality, mining ruining land forms * biosphere: pest/herbicides and mercury killing plants and animals / bioaccumulation