This is a set of flashcards made for revision by topic 1. Foundations of environmental systems and societies. Including: 1.1 environmental value systems 1.2 systems and models 1.3 energy and equilibria 1.4 sustainability 1.5 humans and pollution
Environmental value system (EVS)?
Worldview that shapes the way individuals/ groups perceive or evaluate environmental issues. This can be influenced by culture, economics, religion, and socio-political context.
Ecocentric EVS
Nature is central to humanity.
Humans are dependent on nature.
deep ecologists- self reliant soft ecologists
Anthropocentric EVS
Humans must sustainably manage the global system.
Humans are not dependent but nature can benefit from humankind.
Technocentric EVS
Technological developments can provide environmental solutions.
We can use technology to benefit nature.
Environmental managers- cornucopians
Cornucopians: INDUSTRIAL LEADERS
humans are the most important species
infinite resource
control and managemnet of resources will make us successful
economy mist grow
we can solve any issues
CAPITALISM
Environmental Managers (Stewardship)
humans have an ethical duty to protect and nurture Earth.
Environmental issues need governments to manage and legislate
limited resources need no to be over exploited
Sustainable development/economies are needed
those who suffer from environmental degradation need support from state
Different activist groups?
1)Influential Individuals - often via media publications
2)Independent pressure groups- Greenpeace/ WWF
3)Corporate Business
4)Governments
5)Intergovernmental bodies - UN
Impacts of activist groups?
1) Alter public opinion
2) Alter public behaviour
3) Alter political choices
Silent Spring?
1) a book published by Rachel Carson in 1962
2) started the modern enviromenal movement
3) warned about the impacts of pesticides building along the food chain through bioaccumulation to birds.
4) she suggested DDT was finding its way into human and accumulating in fatty tissues leading to increase cases of cancer.
5) DDT was banned by J.F. Kennedy
Positive impacts of Silent Spring?
The book inspired many such as Al Gore who later published “An Inconvenient Truth” which raised climate change awareness in 2006.
Negative impacts of Silent Spring?
DDT allegations were not backed up by strong scientific evidence. DDT was being used in a global fight to kill mosquitoes. Its ban led to millions of deaths from malaria.
What happened in Chernobyl? (5)
1) 1986 nuclear power plant at Chernobyl, Ukraine went out of control. It led into explosion which released large amounts of radiation into the atmosphere.
2) Happened due to a severely flawed soviet era reactor design, combined with human error.
3) 31 people died within a few weeks of the accident.
4) in 2018, UNSCEAR reported that the accident was responsible for nearly 20,000 documented cases of cancer among individuals who were under 18 at the time of the accident in Belarus, Ukraine, Russia.
5) That was because, high levels of radioactive iodine were released from Chernobyl. Radioactive iodine was deposited in pastures eaten by cows who then concentrated it in their milk which was subsequently ingested by children.
What is a system?
A system is a set of inter-related parts working together to make a complex whole.
What is an open system?
When energy and matter are exchanged across the system boundary. E.g.: Forest
Why is forest an open system? IN DETAIL 8 points
1) Plants fix energy from light in photosynthesis
2) Nitrogen form the atmosphere is fixed by soil bacteria
3) Carbon dioxide is fixed and converted to glucose from the atmosphere
4) Herbivores may move in adjacent grasslands and then add nutrients to enrich soil via faeces
5) Soil minerals may be eroded and transported out of the forest via stream
6) Transpiration loses water to the atmosphere
7) Rain adds water to the atmosphere
8)Heat enters via sunlight
What is a closed system?
When energy is exchanged across the boundary but matter is not exchanged. E.g.: Carbon, Nitorgen, Water cycles, EARTH AS A WHOLE.
The Gaia Hypothesis?
1979 James Lovelock published the Gaia Hypothesis.
He argues that Earth is a planet-sized organism and the atmosphere is its organ that regulates it and connects all the parts.
He argued that the biosphere keeps the composition of the atmosphere within certain boundaries by negative feedback mechanisms.
What is an Isolated system?
No matter or energy is exchanged across a boundary with the environment.
Biosphere 2- Artificial closed system
1) Built in Arizona late 1980s to look at how to colonise space.
2) 2 major issues:
lack of food produced to meet needs of participants
oxygen levels got too low and neede to let oxygen in (making it an open system)
Laws of Thermodynamics
Energy in all systems must follow the Laws of Thermodynamics.
1st Law: Conservation of Energy
Energy cannot be created or destroyed but only transformed from one form to another.
2nd Law: Entropy
Entropy= the measure of disorder in a system
Entropy of a system not in equilibiria will increase over time.
More entropy means more energy is spreading out and there is less order.
Energy transfer is never 100% efficient as when energy is used to do work some dissipates into the environment as wasted heat.
Complexity= Stability
Most ecosystems are complex
Complexity makes them more stable as if one pathway is removed it can be replaced by another.
Simple system= Instability
Tundra- simple system.
populations tend to fluctuate
Removal of one species causes a big change
Equilibria?
The tendency of a system to return to it’s original state following a disturbance.
When a system is in equilibrium a state of balance exist amongst components of that system.
Steady-state equilibrium?
Matter and energy is gained and lost but overall the levels tend to remain constant. EG: open systems
Static equilibrium?
There is no change over time.
Forces in system are balanced and relationship with components remains unchanged over long period of time.
Stable vs Unstable equilibrium?
Stable equilibrium: system tends to return to the original equilibrium after the disturbance.
Unstable equilibrium: system tends to return to a new equilibrium after the disturbance.
Negative Feedback?
Stablizing as reduce change and return to original state.
Positive Feedback?
Destabilizing as continues changes to a new state.
What are the tipping points?
A tipping point is the point at which small changes become significant enough to cause a larger, more critical change that can be abrupt, irreversible, and lead to cascading effects.
Greenland Ice sheet?
The greenland ice sheet contains enough water to raise global sea levels by over 20ft and its melting is accelerating.
What is sustainability?
Use and management of resources that allows full natural replacement of exploited resources and full recovery of ecosystems affected by their extraction and use.
Millenium Ecosystem Assessment- UN
UN funded research programme focusing on ecosystem change.
60% of ecosystems degraded
40% of freshwater soruces have doubled in past 50 years.
25% of fish overharvested
35% magroved destroyed
20% coral degradation
Species extinction 100-1000 times background rate
Reccomendations made
remove subsidies to damaging practices
encourage environmental stewardship
protect areas from development
Environmental Impact Assessment
An EIA is a report prepared before a development project or change in use of land.
they use a cost-benefit analysis of environmental and human health impacts.
What is pollution?
The addition of a susbstance or agent to the environment by human activity.
Primary pollution?
active on emission
direct and indirect effect on living things
unstable
directly targets living organisms
PM, CO, SO2, NOx, VOCs, and heavy metals
Secondary pollution?
formed through chemical or physical changes to primary pollutants
Indirect emmision from source
mostly direct effect on living things
stable
directly targtes ecological system
O3, PAN, acid rain, SPM
Point source pollution
pollution released from a single source. e.g. Chernobyl
easy to monitor and control emission at source
reasonability easily established and managed by law
Non-point source pollution
pollution released from diffuse sources. e.g. cars
monitoring requires extensive survey techniques
responsibility shared amongst many requiring greater effort to enforce change
effects spread over wider area
Persistent Organic Pollutants (POPs)
pollutants which are resistant to breaking down and may remain in the environment for a long time.
often bioaccumulatee in animal tissue and magnify along food chains
high molecular weight
low water solubility
high fat and lipid solubility
halogenated molecules
PCBs (POPs)
PCBs- electrical equipment and coolers until banned in 2001.
found to cause cancer
found in water, animal tissue and as widespread as Arctic Circle
Biodegradable pollutants
breakdown quickly by decomposers, heat or light
short term impacts
less wide spread
Acute vs Chronic pollutions
Acute- large amount released causing a lot of harm.
Bhoqal Disaster in India 1984
Chronic- small amounts released over long time period.
Poor air quality in Beijing
Pollution detection: DIRECT MEASUREMENT
Direct measurement- how much in water, air or soil.
Air pollution: pH of rainwater, gas amounts in atmosphere, exhaust amounts
Water+soil: measurement of nitrates/sulphates, amount of bacteria, heavy metal concentration
Pollution detection: INDIRECT
Indirect measurement: record changes in abiotic and biotic factors as a result of pollutants.
1) oxygen levels in water
2) indicator species
Indicator species
Indicator species such as salmon and bloodworms that can only be found in very clean or very polluted water- are aslo used to monitor pollution levels in waterways.
Pollution management
Changing human activity
regulating or preventing pollutant release
restoring damaged ecosystems