chapter 3/9 developing housing sustainably | housing and how it affects the natural environment & pollution of the environment

what needs do people need?

1. water for domestic use and sanitation

2. space for waste disposal

3. open spaces for recreation

how do cities make space for urban uses?

natural environment such as forestland is cleared

how many acres of forest are lost each year due to deforestation?

18.7 million acres

why is there a growing need for agricultural land?

growing demand of food in urban populations

why is water extracted?

to support domestic and industrial needs

how much water from surface sources do large cities obtain?

80% of their water, and use an estimated 540 million litres of water a day.

how are natural resources used for building materials?

1. wood is taken from trees for the construction of furniture, doors, housing, etc.

2. iron and aluminium are mined from the ground, and mining can bring about wide-ranging negative environmental impacts

what are fossil fuels used for?

fossil fuels are consumed to generate heat and electricity for households

how does the use of fossil fuels harm the environment?

consumption releases greenhouse gases

how can cities have a serious impact to faraway places?

because of cities extracting resources from beyond their physical boundaries (imported from other places around the world).

when does pollution occur?

when substances that are not usually part of the environment are brought into it

what do introduced substances harm in high concentrations?

flora, fauna, and humans

what are the five types of pollution generated by cities?

1. water

2. land

3. air

4. noise

5. light

how is water pollution caused when it rains?

when it rains, surface runoff transports contaminants found in environments into the waterways

what kind of contaminants are found in urban environments? (in relation to previous flashcard)

1. substances from contaminated/polluted soil

2. petrol from vehicles

3. rubber from tyres

4. heavy metals from industries

5. agricultural waste

6. general waste from inconsiderate people i. litter ii. direct washing at water bodies iii. direct defecation at water bodies

why is there a lot of untreated sewage present in the waterways?

1. presence of informal housing, which does not have access to sewage systems provided by the city

2. cracked pipes (due to poor maintenance of infrastructure) can lead to the leaking of untreated sewage

3. the cross contamination of sewage can occur if the treatment process is not well monitored

what are the consequences of polluted water reaching the waterways, drains, and river systems?

aquatic ecosystem is destroyed, impacting human lives and limiting the amount of clean water available

what happens when polluted water infiltrates and percolates into the ground?

it can reach the groundwater of the area, further impacting the supply of freshwater.

how can water pollution be managed?

1. laws and regulations to control wastewater disposal

2. strict wastewater management systems

3. reducing the use of chemical fetilisers

what is the consequence of land pollution?

long-term damage of land, making it unsafe for human use

what are the two types of land pollution?

1. soil contamination

2. improper disposal of waste

how does soil contamination come to be?

contamination can come from industries, agriculture, or sewage systems that release waste on the surface and thus impact soil surfaces

how does improper disposal of waste come to be?

1. general waste from households

2. industrial waste from factories and mines

how can land pollution be reduced?

the disposal of general waste can be managed to reduce land pollution

what are three methods to manage disposal of general waste?

1. build landfills to bury the waste

2. incinerate the waste

3. export the waste elsewhere

what is a small case study of landfills?

the USA has 2200 acres of landfill sites

what is the disadvantage to landfills?

landfills have a tendency to leak and the toxic substances buried inside will contaminate the surrounding soil and eventually, groundwater supplies

what is an advantage to incinerating waste?

incineration means less land will be expended on building landfills

what is a disadvantage to incinerating waste?

the resultant ash from incineration still needs to be disposed of safely

what is a small case study for incinerating waste?

land-scarce singapore incinerates its waste and uses the ashes for its land reclamation projects

what is a small case study for exporting waste elsewhere?

japan exported an estimated 535,840 tonnes of waste in 2019

why does air pollution occur?

1. consumption of fossil fuels for energy

2. toxic emissions from industries and vehicles

why are fossil fuels consumed?

to generate heat and electricity and to power transport

how do toxic emissions from industries and vehicles come to be?

by-product of industrial production

what does air pollution negatively impact?

1. our health

2. flora and fauna

3. damage buildings

how does air pollution negatively impact our health?

people can suffer from chronic respiratory illnesses due to air pollution (e.g. asthma)

how does air pollution impact flora and fauna negatively?

1. dust can settle on plants, reducing their ability to photosynthesise

2. particles in the air can block the airways of animals and restrict their breathing abilities

how does air pollution damage buildings?

1. when harmful substances such as sulfur dioxide and nitrogen oxides are released into the air, they react with water, oxygen, and other harmful chemicals in the atmosphere to produce acidic precipitation known as acid rain.

2. the acid rain eats into the building material and destroys it.

what are the four ways air pollution can be managed by?

1. monitoring air quality and notifying people so that they can take steps to protect themselves when air quality is low

2. encouraging the use of public transport to reduce emissions from cars and motorcycles

3. switching to clean alternative energy sources such as solar energy and hydroelectricity to reduce carbon emissions

4. regulating factories to ensure that they install air pollution control devices such as scrubbers in chimneys

what is light pollution?

excessive, misdirected. and/or obtrusive artificial light (usually outdoors)

what is light pollution caused by?

1. traffic

2. street lights

3. buildings

4. advertisement billboards

what does light pollution negatively affect?

1. human health through stress and anxiety

2. ecosystems that are disrupted

3. astronomical research, as it obscures natural moonlight and starlight

how can light pollution be managed?

1. laws and regulations

2. the use of timers

3. the use of directed light

what is noise pollution?

regular exposure to sound elevated above a certain threshold

at what noise level, and for how long, can noise be hazardous to health?

constant noise above 85dB for more than eight hours

what health affects can noise pollution have?

1. hypertension

2. hearing loss

3. sleep disturbances

4. stress and anxiety

what activities in cities produce noise?

1. street traffic noise (cars, buses, pedestrians, ambulances)

2. construction noise (drilling)

3. airports (noise from air traffic, planes taking off or landing)

4. industrial sounds (turbines, generators, compressors, mills)

how can noise pollution be managed?

1. laws and regulations

2. separation of land use (e.g. proper planning to ensure airports are located far away from housing zones)

what makes the problem with pollution worse?

a high concentration of people in one area

what is a downside to urbanisation? (related to pollution)

urbanisation brings large numbers of people together in cities. this concentrates the waste and pollution produced in a single area.

how do cities manage the large pollution produced?

cities can create efficient control points for pollution as there is infrastructures in place to manage the waste and pollution generated.

what is a case study of cities managing the large pollution produced?

New York City has one of the lowest environmental footprints in the USA. The high-density living in the city can only support smaller homes and its well-connected public transportation network encourages widespread use of public transportation.