8.4 human pop and carrying capacity Flashcards
effective recycling order
- reduce
- reuse
- recycle
reduce
- reducing amount of waste produced and material used
- if reduction starts in design phase there’s less use of raw materials, lower energy consumption, and less waste
- e.g. disposable diapers: super-absorbant polymer (decreases amount of paper pulp used BUT gel is petroleum based so a renewable resource is replaced with non-renewable = material is reduced with sustainability
reuse
- glass: customer pays deposit on bottle and its returned when bottle is collected to be sent back to factory, cleaned, and re-filled
recycling and recycling benefits
- easily recyclable mats: glass, paper, metal textiles, electronics, some plastics
- benefits: prevents loss of useful raw material, reduces consumption of raw mat, reduces energy used, reduces pollution at extraction phase, lowers release of greenhouse gases
- govs offer tax incentives to companies to set up recycling industries and running education programs to encourage recycling
curbside recycling
- residential districts have a day where they put out their recyclables for collection –> downside is collection trucks are operational most days so increase in fossil fuel consumption
recycling centers
- several large bins are placed in publicly used areas
strategies for the 3Rs
- choose products with returnable/reusable/refillable containers
- rechargeable batteries - reduces # of batteries going to waste
- shop at 2nd hand stores
composting
- early times: piling up orgaic mat and leaving until next growing season (worked well when no space or time issues)
- now: composting means reducing amount of waste that ends up in landfills and incineration
- the decomposed organic matter is reused and recycled as soil fertilizers
improvements in composting
- reducing the size and composition of compost
- controlling carbon-to-nitrogen ratio
- monitoring and controlling moisture levels
dealing with waste: educate
- lowest cost
- aim = alter activity producing pollutant
- MEDCs have the 3Rs embedded into people’s minds + have the money and tech to apply the strats but LEDCs apply the 3Rs from need (job opportunities from landfills or searching through bins to resell or reuse)
- economic pressure = most likely to reuse and less likely to waste
dealing with waste: legislate
- aim = to control the release of pollutants
- economic incentives (subsidies) are used to encourage use of the 3Rs
- Europe: political ban of landfill use for hazardous waste encouraged adoption of incineration
dealing with waste: remediate
- used if nothing works
- environmental damage and high financial cost
- reclaiming landfill, waste to energy programs, implementing initiatives to clean up env. –> e.g. removal of plastic from the Great Pacific Garbage Patch + can only reclaim landfill if no toxic waste managed
political and economic pressure
driving people towards incineration and waste-to-energy projects
human carrying capacity
= way to access if a pop or species is living sustainably in an area
- if pop exceeds carrying capacity there will be a crash that brings numbers back to sustainable levels (J-curve)
causes of difficulty defining CC
- we produce non-biodegradable waste which can cause env. degradation + reduce ability of area to provide resources
- resources we use are more varied& there are necessities and luxuries to take into account
- human pop can transport goods
- we employ tech to change env.
- we produce waste faster than the env. can assimilate it
importing waste
- MEDCs import waste into LEDCs for processing
- e.g. Sweden doesn’t have enough waste to keep the waste-to-energy program running so it imports its waste
technology changing carrying capacity
- invention of agriculture changed hunter-gatherer lifestyle to sedentary agriculture –> increased CC
- extensive use of fossil fuels in agriculture
1. mechanisation, pesticides, insecticides, and herbicides increase food production & CC
2. fossil fuels are non-renewable so CC decreases
3. modern agricultural chemicals contaminate groundwater and decrease CC - industrialization of the fishing industry –> catches increase = increase in CC BUT collapse of fisheries so decrease in CC
mechanization
- chainsaws, bulldozers, dynamite means humans can inflict rapid and extensive damage on the natural life-support system (decrease in CC)
arguments against Malthus’s models & theories
the CC can’t be applied to the human pop bc we can outwit the env. constraints
Ecological footprint
A model used to estimate the demands that a human pop places on the env.
- measures amount of land needed to support a pop
2 aspects the EF considers
- Biocapacity –> the earth’s bioproductive land and sea (areas that provide food & absorb waste)
- Demand –> considers amount of bioproductive land we need to provide out of resources and space for infrastructure and absorb waste
lower EF
- renewable resources (wind, water, solar, geothermal)
- limited private transport so people walk, cycle, or use public transport
- limited air travel
- strict emission policies reduce amount of pollution entering atmosphere
- alternative duel used in cars (ethanol, biogas, and diesel have lower carbon emissions) BUT biogas and ethanol take up crop land
what saves space
high-density living spaces
what is bioethanol produced from
corn, sugarcane, and sweet sorghum
lower EF
- using plants for main source of protein = lower EF bc plants are at the bottom of the food chain
- low calorie intake
- locally grown produce
higher EF
- meat and dairy diet –> higher trophic level so more energy loss
- imported food
- high-calorie intake
EF compared to biocapacity
- if EF of a human pop is larger than its biocapacity it means the pop is living unsustainably and exceeding carrying capacity
Peru case study
Has low EF thanks to:
- has an env. minister aiming to use international aid to reduce deforestation and env. pollution
- the env. department dedicates funds to asses state of development concerning EF and biocapacity
- BUT Peru’s biocapacity is decreasing suggesting the pop to be living unsustainably causing damage to env.
Earth Overshoot Day & Eart Day
EOD = the day each year when humans have used up all the resources for the year
- (global biocapacity/world EF) x 365
ED = April 22, raising awareness of the needs for env. protection (started in 1970
