Unit 1 Flashcards
Environmental Value System
An EVS is a worldview or paradigm that shapes the way an individual, or group of people, perceives and evaluates environmental issues, influenced by cultural,
religious, economic and socio-political contexts.
What may influence EVS
Inputs –>education, experience, culture, media
Outputs –> values, arguments , decisions
Historical influnence on EVS
Rachel Carsons Silent spring (1962) –> established of the US Environmental Protection Agency and a ban on domestic use of DDT due to the overuse and impacts on the environment
Ecocentric
Intrinstic value in nature
Puts ecology and nature as central to humanity
less materialistic approach to life with greater self-sufficiency
An ecocentric viewpoint prioritizes biorights, emphasizes the importance of education and encourages self-restraint in human behaviour.
Anthopocentric
humans must sustainably manage the
global system.
This might be through the use of taxes, environmental regulation and legislation. Debate would be encouraged to reach a consensual, pragmatic
approach to solving environmental problems.
Technocentric
Absolute faith in technology
Technology will keep up with the pace of environmental issues and provide solutions if we push too much natura systems
System
A system is a set of interrelated parts and the connection between them that unites them to form a complex whole and produces emergent properties.
A system consits of
Storages (Of matter and energy)
Flows (inputs and outputs from storages)
Processses (transfer o transform energy or matter)
Feedback mechanisms that mantian sustainability
Open system
An open system exchanges matter and energy with its surroundings.
ex. ponds
Closed system
A closed system exchanges energy but does not exchange matter with its surroundings.
ex. nitrogen cycle, carbon cycle
Difference between energy and matter
Energy flows but matter cycles
Source of energy in any system
solar radiatiom
Flows of enegry occur as
Transfers or transformations
Transfer
simply move energy or matter from one place to another without changing it in anyway.
transformations
move energy and matter but in the process of doing so there is a change of state or form.
Model
simplified version of reality that tells a story about what happens in the natural world.
Advantages of a model 4
- helps illustrate complex concepts and allow predictions
- Brings out patterns
- easy to understand
- Study to small or too large things
Disadvantages of a model
- lacks detail , not accurate
- false impression, no figures
- oversymplified, misundertandinsgs
- Size miselading
Laws of thermosynamics
- Law of conservation of enegry
- Entropy and the second lae
Law of conservation of energy and implications (5)
energy cannot be created or destroyed
1. Energy has to keep entering the system to keep it functioning
2. In food chaiin energy transforms light to chem to heat and increases entropy –> less work less animals at Higehr Trophic level
3. if there are non bioderabae toxins in chain, they become progressibley concentrated - bioacc
4. energy cannot be created
5. no new energy enters universe
Entripy and the second law
the entropy of a system increases over time; the only way to avoid entropy is a continuous input of additional energy like food and sunlight
Entropy- increase in disorder of a system
increase in entropy –> decrease in energy for work
Negative feedback
(Stabalizes) it reverses the change and returns the system to the original state of equilibrium.
Positive feedback
(destabilizes) amplifies the change in the system and keeps it going in the same direction. So a small disturbance in the system causes an increase in that disturbance towards a tipping point
Tipping point
A tipping point is the minimum amount of change within a system that will destabilize it, causing it to reach a new equilibrium or stable state.
Stable equilibirum
A stable equilibrium is the condition of a system in which there is a tendency
for it to return to the previous equilibrium following disturbance.
Steady state equilibrium
A steady-state equilibrium is the condition of an open system in which there
are no changes over the longer term, but in which there may be oscillations in the very short term.
MOST ECOSYSTEMS
Stability
is the ability of an ecosystem to remain in balance.
Resistance
When the ecosystem continues to function during a disturbance.
A resistant ecosystem will respond to a disturbance with self-regulating mechanisms (negative feedback) that maintain the system in a steady state during a disturbance.
Resilience
The ability of the ecosystem to recover after a disturbance.
A resilient ecosystem will respond to a disturbance with self-regulating mechanisms (negative feedback) that return the system to a steady state after any disturbance.
Factors that affect stability (5)
1.climate and limiting factors –> less extreme climate less likeley to push to tipping point
2. Biodiversity –> more complex, more stability
3. Trophic complexity –> many trophic levels–> more complex
4. Nutrient stores –> more stores , more stable
5. Frequency and intensity of distrurbances
Sustanavility
Sustainability is the use and management of resources that allows full natural
replacement of the resources exploited and full recovery of the ecosystems affected by
their extraction and use.
natural capital
Natural capital is a term used for natural resources that can produce a sustainable
natural income of goods or services.
Natural income
Natural income is the yield obtained from natural resources.
What is the MA and what did it do
Millenium ecosystem assesment
The Millennium Ecosystem
Assessment (MA) gave a scientific appraisal of the condition and trends in the world’s ecosystems and the services they provide using environmental indicators, as well as the scientific basis for action to conserve and use them sustainably
What is EIA
Environmental Impact Assessment (EIA) is formal process that is put into action before something major can be changed, for example a project such as a building, change of land use or mining activity. The aim is to:
1. identify impacts
2. impove decision making
3. Lessen any potential impact
Steps
1. scoping
2. Baseline Study
3. Predicting and Assesing Effects
4. Mitigarion
Critisism of EIA
the lack of a standard practice or training for practitioners
the lack of a clear definition of system boundaries and the lack of inclusion of indirect
impacts.
Pollution
is the addition of substances into the natural environment at a rate that is greater than that at which they can be rendered harmless and which causes adverse changes.
Orgganic and inorganic pollution
Organic –> pollutant is something that is or was living, such as human sewage, silage, etc.
Inorganic –> pollutant is one that is non-living and generally does not contain carbon, such as nitrates and phosphates from artificial fertilizers
Persistent vs biodegradable pollutant
Persistent –> do not breakdown easily and the most dangerous ones are the persistent organic pollutants (POP’s). Insoluable in water
Biodegreadable –> pollutants are substances that will breakdown or decompose due to the action of microorganisms, such as human sewage, food waste etc.
acute vs chronic pollutant
acute –> pollution occurs suddenly and in large quantities over a short period of time, for example a sudden rupture in an oil pipe is an acute problem.
Chronic –> pollution is the persistent long-term release of a pollutant at low concentrations
Primary vs secondary pollutants
Primay: pollutants are released into the environment directly from a source in the form they are produced.
Secondary: y pollutants form when primary pollutants react with the environment and other pollutants
Pollution management model 3 steps
Educate, legislate, remediate
What is DDT and why was it usefll
organochordie insecticide that is colourless, tasteless and odourless.
highly effective in controlling malaria and typhus during World War II
agricultural purposes after the war.
Why is DDT dangerous
persistent organic pollutant (POP) (means that it does. not brea down that is absrobed by the soil once spread.
make the way through food chain and become more concentrated.
Who wrote a book about DDT
Rachel Carson - Silent Spring - identifyed DDT impacts like how it bioaccumulates within fat tissues and biomagnifys up the food chain becoming increasingly concentrated at each trophic level
This bood lead to the ban of DDT in agricultural usage
Problems of DDT to Top predators and humans
Lowers reproductive success
Ex. Predaroy birds suffer fromm eggsehll thining
DDT in humans –>cancer, reprodicrive system, lver damage
Controversy in DDT
Recognized that a total ban was not feasible due to lack of cheap effective alternatives
Environmentalists –> DDT is harmful to humans and environment and should be banned
Humanitarins –> DDT banning cause the death of millions of people
