ess topic 8


8.1


population: a group of individuals of the same species occupying a specific area at a given time.


demographic tools

  • crude birth rate: # of births in a year per 1000 in a population 

    • (# of births/ total pop)1000

    • factors:

      • population age structure

      • women’s right 

      • access to food/clean water

      • desire to have kids

      • wealth

  • crude death rate: # of deaths in a year per 1000 in a population

    • (# of deaths/ total pop)1000

    • factors:

      • age population structure

      • access to clean water

      • sanitation

      • wealth

      • sanitation

  • immigration: movement of people into an area

    • (# of immigrants/ total pop)1000

  • emigration: movement of people away from an area

    • (# of emigration/ total pop)1000

  • total growth

    • births + immigrants - death - emigrants 

  • natural rate increase

    • (CBR-CDR)/10

  • total fertility rate: average # of kids per women of child-bearing age

    • sum of # of kids per women x length of age group

  • infant mortality rate

    • (# of infant deaths (under 1)/ # of live births)1000

  • doubling time: the amount of time it takes for a country to double its pop

    • 70/NIR (yrs)


historical population growth

  • the human pop has been growing exponentially 

  • consequences:

    • increase in waste

    • increase in pollution

    • increase in deforestation

    • increase in ecological footprint

    • increase in use of resources 


population related models

  • population pyramid

  • demographic transition model: illustrates the pop transition from an pre-industrial stage with high birth/death rates to an economically advanced stage with low/declining birth/death rates 

    • factors:

      • gender equality

      • sanitation

      • economic factors

      • policies

    • stage 1

      • high birth

      • high death

      • population fluctuates/but otherwise is stable and low

      • no countries

    • stage 2

      • high birth

      • declining death

      • population increases at a rapid rate

      • afghanistan

    • stage 3

      • declining birth

      • declining/stabilizing at a low level death

      • population increasing at a smaller rate

      • brazil and argentina 

    • stage 4

      • declining/stabilizing at a low level birth

      • low/stable death

      • population stabilizing/fluctuates

      • uk and us

    • stage 5

      • low/stable birth 

      • low/possibly increasing death

      • declining population 

      • japan and sweden


policies to reduce pop growth

  • taxes and limited job opportunities 

  • promoting immigration

  • policy that stimulates economic growth leads to education leads to knowledge of birth control and sex ed

  • policies to educate and empower women


UN pop projection model

  • high fertility leads to population increase

  • low fertility leads to population decrease

  • advantages:

    • models are easy to read

    • allows for future planning

    • can assist in making decisions about resources

    • policymakers can see the potential impact

  • disadvantages:

    • models are simplified therefore inaccurate

    • model used could be imperfect

    • human behavior can change

    • cannot predict natural disasters


policies as a way to control pop

  • pro-natalist: in favor of increasing birth rates

    • RU has had low fertility rates for decades due to aging pop, women preferences, high divorce rates

    • 1936: if you have babies there are rewards 

    • 1941-1990: childless tax

  • anti-natalist

    • in favor of decreasing birth rates

    • china’s one child policy



8.2


urban systems: at interconnected system of buildings, microclimate, transport, g/s, power/E, water supply, humans, plants, animals.


urban ecosystems:  a community of organisms interacting with their abiotic environment within an urban area.


urban area: a developed area with high density in population, buildings, infrastructure.


inputs

  • matter: food, water, building materials

  • people: immigrants, commute

  • energy: chemical energy, fossil fuels, electricity

  • information: data, communicative systems

processes

  • storage: materials kept in tanks, warehouses

  • transfer: moving resources through infrastructure (pipelines, roads)

  • transformation: converting resources to usable forms

outputs

  • waste

  • pollution: CO2, nitrogen dioxide, heat:noise

  • goods/services: manufactured products

  • data/info: digital output

  • people: emigration


urban efficiency: meet human needs within planetary boundaries and maximizes services like light, transport, etc.

  • challenges:

    • hard to define outputs that reflect the full function of the city

    • real efficiency produces positive impacts to both environment and humans


urban resilience: the ability of urban system to bounce back for disturbances.

  • diverse/abundant resources:

    • local/distributed sources of energy, food, etc

  • robust infrastructure 

  • diverse pop and strong social networks 

  • strong govt

  • why urban resilience

    • climate change and social instability requires city to be adaptable and durable

    • most cities now aren’t resilient enough


urban interconnectedness

  • urbanization: movement of population from rural to urban areas

    • push factors:

      • lack of employment/wage

      • food scarcity

      • lack of basic services

      • lack of resilience

    • pull factors:

      • employment/high wage

      • food abundance

      • abundant services

      • resilience 

  • urban sprawl: unrestricted spread of low dense urban and suburban development around the outskirts of cities.

    • causes:

      • lower land values

      • pop growth -> more houses

      • high income -> afford houses

    • consequences:

      • increased use of cars

      • reduction in natural sites

  • suburbanization: movement of people from central urban areas with dense pop to outskirts with lower density

    • reasons:

      • improvements in transportation 

      • increase in global trade 

    • results:

      • lead to uncontrolled urban sprawl 

      • reduce biodiversity, lack of green space


impacts of urbanization (urban areas) on ecosystems 

  • loss of forest/agricultural land

  • water quality and river flows

    • broken pipes from toilets/kitchen appliances leads to water pollution in urban areas

    • construction near rivers affects their natural flow

  • energy consumption

    • urban use large amount of energy to power domestic, service, and industrial activities

  • air pollution

    • more vehicles and industrial activities

  • resource waste

    • volume of water consumed

    • low recycling rates due to small space


urban planning

  • modern urban planning: brasilia, forest city, sustained city

  • doughnut economic model lenses: a holistic framework for sustainable and regenerative urban development 

  • local social lenses

    • focus on human well-being and social equity

    • cities must provide

      • affordable housing

      • clean water and food

      • education

      • transportation 

      • job

    • challenges 

      • marginalized groups often lack access

        • poor infrastructure

        • physical barriers

        • inadequate services

  • local ecological lens 

    • emphasizes regenerative urban planning and urban ecology

    • provide ecosystem services

      • air purification

      • carbon storage

      • biodiversity 

      • water filter

      • cooling and green space 

    • urban planning

      • regenerative architecture 

        • solar panels/rainwater harvesting 

        • renewable energy

      • urban farming

        • horticulture: growing crops in urban an locations

          • rooftop farm -> nature ubraine paris

        • aquaculture: aquatic organisms in lakes, rivers, ponds 

        • vertical farming

        • urban beekeeping 

        • advantages:

          • production of large amounts of food

          • income/employment

          • food security

      • biophilic designs 

        • green walls and roofs

        • natural light

      • urban ecology: relationship of living organisms with their surroundings in urban areas 

        • green space, parks 

      • resilience planning

        • building on stilts 

        • fall safe grids

  • global ecological lens

    • city must operate within planetary boundaries

    • reduce environmental impact

      • lower carbon emissions

      • minimize energy use

      • control pollution

    • strategies

      • use renewable energy 

      • promote public transport

  • global social lens

    • urban decisions must consider global social justice 

    • examples

      • promote social equity through local policies

      • support refugees



8.3


urban air pollutants

  • air pollution: introduces particles and other substances into the earth’s atmosphere can cause diseases, etc.

    • causes

      • inputs from human activity to atmospheric systems

  • primary pollutants: directly active at the point of emission -> forest fires, dust, volcanic eruptions

    • natural and anthropogenic sources

    • indicator species: organisms used to assess a specific environmental condition

      • lichens (low sulfur dioxide)and nettles (high phosphorus)

    • nitrogen oxide

      • car engines, power plants

    • sulfur dioxide

      • volcanic eruptions, power plants, vehicles

    • carbon monoxide

      • motor vehicles

    • particulate matter (PM10 PM2.5)

      • tiny particles/droplets in the air

        • construction sites, unpaved roads

  • secondary pollutants: formed when primary pollutants react with each other 

    • nitrogen dioxide

    • ammonia

    • nitric acid

    • tropospheric ozone


strategies to reduce urban air pollution

  • improve public transport

  • infrastructure for cycling

  • grow trees

  • green walls

  • limited car use

  • pedestrianized town centers 


acid rain

  • caused by combustion of fossil fuels produce sulfur dioxide and nitrogen oxide as primary pollutants -> reacts with water in the air

  • pH 

    • 0-14

    • less than 7 = acidic

    • more than 7 = alkaline

  • impact

    • terrestrial

      • damage plant foliage thus hindering growth and killing them

      • make soil toxic

      • leeching of nutrients

    • aquatic

      • harms ph sensitive organisms phytoplanktons

      • fish eggs don’t hatch, gills damaged 

      • solubilization: toxic metals dissolve in water -> harm organisms and water to drink

    • humans

      • release toxic metals to drinking water

      • cause lung damage 

    • buildings/infrastructure 

      • corrode materials like marble, limestone (liming)

      • weakens buildings


management strategies for sulfur and nitrogen oxide 

  • altering human behavior

    • individuals

      • public transportation 

      • buy local goods

      • save energy at home

      • plant trees

    • businesses

      • switch to renewable E

      • use cleaner material 

      • support remote work

    • govt

      • set limits to pollution -> carbon tax

      • invest in public transport 

      • fund cleantech and raise awareness 

  • regulating and reducing

    • removal of SOx prior to combustion

    • reduction of SOx emitted during and after combustion

  • controlling pollution at its source

    • use tech to reduce pollution where it’s made

      • catalytic converters (in cars)

        • turns harmful gases to less harmful ones 

      • scrubbers

  • restoration

    • clean up pollution and repair damage -> costly

      • liming: add limestone to lakes, rivers to raise pH -> costly

      • lime acidified forests to help neutralize soil acidity

      • replant forests

      • for human health

        • wear masks

        • ensure access to high quality healthcare