geography: urbanisation & environmental change and management: yr 10 exam

exurban economy

a semi-rural region lying just beyond the suburbs of a city

formal economy

economic activities that are taxed and regulated by the gov

megacity

city w/ 10 million+ people

population density

the number of people per square km

regional centre

a rural city that supports smaller surrounding towns with services

urban decay

deterioration of the built environment i.e. infrastructure falls to state of despair and buildings left uninhabited

world city

city considered important to the global economy e.g. tokyo, london, sydney

urbanisation

The process by which an increasing proportion of a population lives in towns and cities

urban consolidation

the process of increasing or maintaining the density of housing in established residential areas. The ultimate aim is to reduce development on the city's fringe areas.

decentralisation

Industries begin to move out to the suburbs for more land and so did the residents who no longer had jobs in the area. This is called the doughnut effect.

ecological footprint

surface area required to supply a city with food and other resources and to absorb its wastes.

how many australians live in urban areas

around 90%

why does aus have an ageing population

fertility levels low, life expectancy high = ineffective replacement rate

where is most of aus's urban population

east coast

historically, why are australians settled this way

gold rush pulled many people to vic and nsw

what climate factors make east coast desireable

- subtropical, warm climate
- sufficient rain = reliable water source

how does transport aid urban sprawl

allows people to live further from the city centre but still be able to get there quickly for essential infrastructure

cons of urbanisation

- strains on water & food supply, increased emissions, threatens biodiversity and habitats

ways to improve sustainability at a city scale

reduce traffic, protect natural systems, improve waste management etc.

internal migration

number one driver on population redistribution in australia leading to growth in the cities

at what age does internal migration peak

young adults and small peak at retirement

intrestate vs interstate

intrestate is movement within a state whereas interstate is movement between states

what are some pull factors for QLD?

- warmer, tropical climate in QLD
- desire for a sunny sea change
- education or employments
- lifestyle

examples of economic migration

fly-in, fly-out workers, seasonal workers

where is most of china's urbanisation

south east

why are most chinese people settled in the east

west is very mountainous and east has better rivers and water supply

what is the hukou system

separates rural residents from urban residents, meant that rural residents were not entitled to all the benefits and privileges to those with urban hukou status

source function

the ability for the environment to supply resources depending on demand. can be renewable or non-renewable

service function

the environment’s processes that support our life without requiring human action to produce them making our earth habitable.

sink function

the environment’s ability to break down, safely store, recycle or absorb wastes.

spiritual function

it’s recreational, psychological, aesthetic and spiritual value to people. the land may have value to certain cultures beliefs or religions.

aeolian processes

processes involving wind

formation of waves

- wind blows over water surface
- friction is created with the bottom layer of wind and the top layer moves ahead
- top layers of wind topple over creating circular motion of water (eddies)
- waves are created and wind on back of waves pushes them forward
- energy of wind causes circular oscillations beneath wave crests

how do waves break?

- friction is created between bottom of wave and seafloor closer to shore
- waves steepen and become unstable
- waves break and become breakers

size and energy of wave is influenced by

wind strength, time the wind has been blowing
distance wave has travelled (fetch)

sources of wind causing waves

localised wind and offshore weather events

types of waves

spilling, plunging and surging

constructive waves

when the swash is stronger than the backwash, carrying sediment up the beach

destructive waves

have a backwash more powerful than the swash, pulling material away from the shore

biophysical processes

erosion, deposition, transportation

longshore drift

- the prevailing wind directs waves towards the shoreline at an angle (at cronulla the wind comes from a SE direction)
- the waves push the swash up the beach, depositing sediment (sand)
- the backwash the falls back down the beach at a right angle due to gravity
- this causes sand to move up along the beach (northerly in cronulla

what landforms can longshore drift create

tombolo

erosion

condition in which the earth's surface is worn away by the action of water and wind

deposition

the natural process of laying down a deposit of something

characteristics of a low energy coastline

-broad beach, fine sand, less than 5° slope

characteristics of a high energy coastline

little sand, rocks and pebbles, beach steeper than 5°

abrasion

the process by which fine particles in the water erode the surface of a material

cliff

when the bases of headland are eroded by sea and wind causing the above rock to fall creating a steep face

sea cave

opening in coastal rocks or cliff caused by erosion- usually in rocks weaker than those surrounding

blowhole

hole in the ground that connects to an underground, partially submerged ocean cave

wave cut platforms

rock surfaces that have abraded causing the rocks to be smoothed

sea arch

opening in coastal rocks, often begin as two sea caves

sea stack

when arches give way and become a pile of rocks

long sand bar or spit

an extended stretch of beach material that projects out to sea

baymouth bar

sand bar extending between two mouth points in a bay

tombolo

narrow piece of land made of sand that connects an island to the mainland or another island

barrier islands

thin chain of sand bar islands

hydraulic action

force of waves hitting the shore

corrosion

salt causing weaker layers of rock to dissolve or disintegrate

corrasion

particles/material in waves that roll back and forth across the shore abrading

sand dunes

accumulation of sand where sand is blown (aeolian process) from shore back to beach

primary dunes characteristics

- closest to the beach
- stable and well vegetated dunes, stops sand being blown inland

what kind of vegetation is on the primary dune

vegetation on foredunes has to be hardy and able to withstand nutrient poor soil and sea spray e.g. spinifex

why do we need coastal management?

erosional processes mean that sediments are redistributed and the processes become a problem when they threaten our human environments and infrastructure

what is the threat of erosion at elouera

there are no sand dunes left and the surf club and restaurant are built on the beach with roads and houses built on and supported by these dunes. If these dunes were to be eroded too much, the infrastructure may collapse.

what is coastal management

the halting of land loss and erosion at a particular point

hard management strategies

controls the sea by building barriers between the sea and land

pros of sea wall

durable concrete, reflects waves and prevents scouring, varying styles

cons of sea wall

not aesthetically pleasing, cost ineffective

pros of groynes

prevents the impacts of longshore drift by containing sand in one section of the beach

cons of groynes

sand on opposite end of groynes still gets eroded and as sand continues to move more groynes need to be added

pros of rock gabions

effective percolation, more cost-effective, permanent

cons of rock gabions

not aesthetically pleasing

pros of metal piling

simple, more cost-effective, reflect or dissipate wave energy

cons of metal piling

not aesthetically pleasing

history of elouera sea wall

flat sea wall built in 1950s, strong waves caused erosion as the water scoured, wall collapsed in 1974 as the supporting sand eroded. sea bee wall built by bate bay coast line management committee in 2008.