Urban sprawl - when a city grows in physical size aswell as an increase in population. When urban areas develop more people are attracted, therefore more building space is required.
Counter-urbanisation - when people move away from the city.Recently more people have moved to the urban fringes where the environment is better with more space. These are usually middle-aged people with fmailies which they do not want to raise in the CBD (central business district).
Rural - urban migration - moving from the countryside to the city. This is due to pull and push factors.....
Push factors Pull Factors
Natural disasters Jobs
Natural Hazards in urban areas
SOMETHING ONLY BECOMES A HAZARD IF IT AFFECTS PEOPLE e.g If there is a thunder storm, trees fall down but everyone is inside and safe, it is NOT a hazard. If there is a thunder storm, trees fall down on a main road, cause an accident and 4 people die, it IS a hazard.
- floods - lots of concrete in cities, water cannot easily drain away, green zones are necessary around rivers to help it drain naturally
- earthquakes - buildings can fall and destrucs roads and other buildings
- tsunamis - sweep away constructions and cause major flooding
- heavy rainfall - can cause flooding
- snow - cause danger on roads and cause lots of congestion
- winds - wreck shanti towns and bring down sign posts and bill boards
- mud slides - damage housing below, often shanti housed are built on slopes
L.A is under the threat of natural hazards as it runs throught the San Andres fault line (boundry between 2 tectonic plates).
Popultaion increase makes the risks harder to manage.
Earthquakes are common in L.A, they can cause landslides and tsunamis.
To help decrease the level of destruction L.A is prepared with buildings with a special structure made to withstand earthquakes plus, buildings are not built on steep slopes.
Urban growth problems
Urban growth can cause:
- Pollution - fewer jobs
- Litter - poor people have to move
- Destruction of habitats - farmers' land is taken
Problems occur in MEDC's due to urbanisation e.g :
polluted water, no landscape, demand for transport, sewage, waste burnt, limited jobs, smogs
Pollution and Transport are linked topics, linking is a good exam technique so these are ones to remember
Fumes from factories, houses and vehicles are released into the atmosphere, the higher the population the more fumes there are. Too much pollution can lead to a smog, this ia a heavy cloud of fumes which hang over a location, it can lead to health problems such as asthma.
Renewable energy should be encouraged - People should be persuaded to purchase solar panels, there should be a mixture of solar, wind, hydroelectric, hydrogen and tidal energy combined as a cities main energy source so it is reliable and there is always energy generated from different sources.
Improvements in transport
- Make it more regular and cheaper
- Charges for private vehicles to enter the city
- Park and Ride schemes - more convinient for commuters, don't drive into city
- Linked transport e.g a bus from park and ride to a train, then a tram running through the CBD.
If transport becomes a major problem, there could be quotas for the amounts of car usage allowed in the city, also fuel prices could be increased and perhaps only carbon neutral fuels could be used like vegetable oils.
Sustainibility - Meeting the needs of today in a way which is beneficial for future generations
Factors which can create a sustainable environment
- public ransport
- green zones
- renewable sources
- energy efficient homes and businesses
- waste managment
Beddington Zero Energy Development (BEDZED)
- south facing buildings - maximum sunlight
- self sufficient heating power
- private solar and wind power
- natural materials are used for construction and living
It was completed in 2002 and is the UK's 1st major zero energy development. There are nursaries and boardrooms to make the community convinient and suitable for business work.
- foggy, fumey air (developing smog)
- untreated landfill sites
- exposed sewage - disease
- loss of eco-system due to urban sprawl
- work unavailable
- crime regular
This is a megacity in China with 1/2 million residents, in 2020 the population is estimated to have doubled. It is one of the most polluted cities on Earth.