Sustainability
The use and management of resources that allows full natural replacement of the resources exploited and full recovery of the ecosystems affected by there extraction and use
Ecological footprint
the area of land and water required to support an individual by supplying all resources and assimilating all wastes (measured in global hectares)
Biocapacity
the capacity of ecosystems to regenerate what people demand from those surfaces
Ecological footprints are increased by
reliance on fossil fuels
large per capita consumption of food
large per capita consumption of energy
large per capita production of waste
reliance on a meat based diet
Ecological footprints are decreased by
shifting to renewable energy resources
practicing the reduce, reuse, recycle and compost mantra
improving the energy efficient of our possessions
consuming more plant based foods
consuming more locally grown foods
reducing use of fossil fuels by using public transportation, biking, or walking
improving technology to use fewer resources
Ecological Footprint and Carrying Capacity
A country’s carrying capacity is inversely proportional to its ecological footprint
the smaller the footprint, the more people the country can support
Modeling Ecological Footprint
Although an ecological footprint is supposed to account for all resources used and all wastes that need to be assimilated, it is not practical to factor all of these inputs into the calculations.
For simplicity, the footprint usually focuses on carbon dioxide emissions associated with resources consumed and waste generated.
The ecological footprints usually underestimate the impact of individuals on the environment but it does provide a quick overview of the consumptive habits of the country.
Who generates that other organisms cannot use?
Humans
Generating Waste
Until a society becomes relatively wealthy it generates very little waste
Planned obsolescence
The process of designing a product so that it will need to be replaced within a few years
Waste
Material that has no value to its producer/consumer
Municipal Solid Waste (MSW)
Refuse collected by municipalities from households, small businesses, and institutions. (includes both trash and recycling)
Solid Domestic Waste
MSW continues to increase as society develops
More and more of the waste generated is not biodegradable
E-Waste
electronic waste (TV’s, music players & cell phones)
E-Waste pollution
Most e-waste contains heavy metals like lead, cadmium, and mercury. Heavy metals that leach into the watershed can cause neurologic disorders.
E-waste also contains precious metals like copper and gold. Recycling of e-waste is rare and many of these precious metals are simply discarded.
E-Waste programs
There are voluntary programs in some communities designed to divert e-waste from landfills
However, in the US most electrics are not designed to be easily dismantled making recycling of these products difficult and expensive--it is often cheaper for them to go to a landfill.
Plastic Waste
The amount of plastic produced (and wasted) each year continues to grow.
Plastic is pervasive in our packaging and our goods.
The more developed…
the more waste
The Great Pacific Garbage Patch
Ocean gyres cause plastic and other floatable trash to accumulate in certain areas. These areas are known as garbage patches.
The waste is not continuous but it is at a much higher density in these areas as opposed to other open water areas.
Types of marine debris
plastics (make up 60-80% of all marine debris)
styrofoam
glass
rubber
derelict fishing gear
derelict vessels
What is the main problem
The Great Pacific Garbage Patch presents numerous hazards to marine life, fishing and tourism.
Since the Great Pacific Garbage Patch is so far from any country’s coastline, nations refuse to take responsibility or to provide the founding to clean it up.
Charles Moore, the discoverer of the patch in 1997, once said that cleaning the patch would “bankrupt any country” that tried it.
Managing Waste Model
Reduce, Reuse, Recycle
RRR Example
Alter:
Education campaigns about food waste/plastic pollution
Control Release
Legislation to encourage recycling and reuse initiatives
Taxes on waste disposal, plastic bags (5 cents), single use plastic
Bottle deposits or recycling systems (sweden)
Reusing plastic instead of making new - reduced energy consumption by 66%; half of NOx, â…“ SOx, 90% less water
Remediate
Reclaiming landfills
Ocean Cleanup (similar initiatives to remove plastics from oceans and rivers
Clothing brands reuse plastic waste
Sanitary Landfills
A method of disposing of solid waste on land without creating nuisances or hazards to public health or safety
Waste is layered with soil = decomposition and control odor.
Bacteria decompose waste and the weight of the trash above helps compact lower levels.
Sanitary Landfill Notes
US requires that all landfills be located away from wetlands and transform faults
Landfills must be 20 ft above water table
Landfill must be lined with plastic and impermeable clay.
Leachate is treated on site for at least 30 years after landfill has closed.
Groundwater is also monitored regularly for contamination.
Methane gas produced during decomposition is collected and can be used for energy generation.
After a landfill is closed, it is capped to prevent water from seeping down and gas from seeping up.
A closed landfill can then be converted into public grounds.
Sanitary Landfill Downsides
Leachate may escape from well lined landfills
Decomposition slows when tightly compressed and dry (intact food, green grass clippings, newspapers have been found decades after burial)
Methane, a greenhouse gas, is released as organics decompose
NIMBY (Not in my backyard). Landfills need to be near population centers to make them economically viable, but no one wants to live near a landfill.
Incineration
a process where selected garbage is burned at high temperatures
What waste disposal technique reduces trash weight by 75% and volume by 90%
Incinerators
Incineration downside
AIr pollution, acid rain, global warming
Dioxins, heavy metals, and PCBs can be released into the atmosphere with incineration.
Emissions are closely monitored and some countries have banned incineration completely.
Ash that remains must be disposed of in a hazardous waste landfill.
Incinerator notes
Wet scrubbers spray water mixed with active chemicals to collect pollutants out of the air. The heavy wet pollutant then falls out of the air and is collected.
Dry scrubbers have a lime filter that collects pollutants.
The collected pollutants are disposed of as hazardous waste.
The Baghouse is another series of filters that can capture some more particles that pass through the scubbers.
Even with the addition of a baghouse and scrubbers, toxic particles are still emitted in incinerators.
Positives:
Bottom ash can be recycled and used to build roads
No groundwater contamination
Retrieve metal from ash which can be recycled
Natural Captial
Resources that are not manufactured but have a value to humans
Natural Income
The money earned from natural capital. Can also represent growth in natural capital
Renewable Natural Capital
Living natural resources that have a sustainable yield equal or less than their natural productivity. They are self-producing and self-maintaining (ex. Timber, food crops)
Non-Renewable Natural Capital
Natural resources that cannot be replenished within a time scale of the same order at which they are removed and used (ex. fossil fuels)
Resources can be valued in the following ways
Economic, ecologic (providing an ecosystem service), scientific, and intrinsic
Maximum sustainable yield
the maximum harvesting of a given resource that does not result in a reduction to natural capital
MSY
= (annual growth and recruitment) - (annual death and emigration)
&
= (biomass/energy) time (1) - (biomass/energy) time (0)
Sustainable societies will
Discourage earth degrading behavior
Use full cost pricing
Increase productivity through technology
Reduce poverty
Slow population growth
The value of natural capital is…
dynamic (changes based on demands and current technology)