1.1 - Environmental value systems

• Environmental value system (EVS): a worldview that shapes the way an individual or group perceive and evaluate environmental issues

  • Examples: culture, religion, economic and socio-political context

• Who is included in the environmental movement?

  1. Influential individuals: often use social media to raise awareness

  2. Independent pressure groups: they use awareness campaigns to make a change. They influence the government and corporate business organisations → Non Governmental Organisations (NGO’s)

  3. Corporate businesses: multinational corporations (MNC) and transnational corporations supply consumer demand and create environmental impact

     • mining for minerals or burning of fossil fuels

  4. Governments: make policy decisions which include environmental ounces, such as planning permission for land use, applying legislation to manage emissions controls over factories

  5. Intergovernmental bodies: these groups hold summits about earth to bring governments, NGOs and corporations to consider environmental and world development issues

• Categories of EVS:

  • Ecocentric worldview: puts ecology and nature as central to humanity (less materialistic lifestyle)

    1. Deep ecologists

    2. Soft reliant, soft ecologists

  • Anthropocentric: believes humans must sustainably manage the global system

    • Humans are not dependent on nature but nature is there to benefit from mankind

  • Technocentric: believes that technological developments can provide solutions to environmental problems

    1. Environmental managers → technocentrists

    2. Extreme technocentrists → cornucopians

• Cornucopians: people who see the world as having infinite resources to benefit humanity. They think that technology can solve any problem

• Environmental managers: believe that we have an ethical duty to protect and nurture the earth

• Biocentric: thinkers see all life as shaving value for its own sake, not just for humans. Humans should not cause premature extinction of any species

  • the ultimate source of energy for all organisms → sun

• Deep ecologists: put more value on nature than humanity. They believe in biologists, universal rights where all species and ecosystems have value and humans cannot interfere with it

1.2 - Systems and Models

• System: set of interrelated parts working together to make a complex whole, can be living or nonliving. Systems are all more than the sum of their parts

  • Can exist in many scales (large or small)

  • Can be open, closed, or isolated, though most systems are open

  • Material and energy undergo transfers and transformations in flowing from one storage to the next

  • Biosphere = atmosphere + lithosphere + hydrosphere + ecosphere

• Systems can be closed, open, or isolated

• Biome: can be seen as an ecosystem. It helps if the ecosystem has clear boundaries

• Biosphere: is a fragile skin on planet earth. Includes atmosphere (air), lithosphere (rocks), hydrosphere (water)

• All systems have:

  1. Systems (stores of matter/energy)

  2. Flows (into, through, and out of the system)

  3. Inputs

  4. Outputs

  5. Boundaries

  6. Processes (which transfer or transform energy or matter from storage to storage)

• Matter (material) and energy flow through ecosystems as:

  • Transfers: when energy or matter flows and changes location but does not change its state

    • Movement of material → in a non-living process

    • The movement of energy

    • Movement of material through living organisms

• Transformations: when energy or matter flow and changes its state, a change in the chemical nature, a change in state or energy

  • Matter to matter

  • Matter to energy

  • Energy to energy

• Transfers require less energy → more efficient than transformations

• An open system exchanges matter and energy with their environments; all ecosystems are open systems

  • Examples: in forest ecosystems:

    • Plants fix energy from light energy entering the system during photosynthesis

    • Nitrogen from the air is fixed by soil bacteria

    • Water is lost through evaporation and transpiration from plants

• A closed system exchanges energy (not matter) with its environment. They are extremely rare in nature

  • Light energy enters the earth’s ecosystem in large amounts and some is eventually returned to space as long-wave energy (heat). This is how a closed system operates.

• An isolated system neither exchanges matter nor energy with its environment. They do not naturally exist; the entire universe is an isolated system.

• Models are simplified versions of systems, it could be:

  • A physical model (a wind tunnel)

  • A software model (climate change or evolution)

  • Mathematical diagrams

  • Data flow diagrams

• Advantages of Models:

  • Easier to work with than complex reality

  • Used to predict the effect of a change of input

  • Can be applied to other situations

  • Used to visualise small and large things

  • Can help us observe patterns

• Disadvantages of models:

  • Predictions may be inaccurate

  • Accuracy is lost

  • Model will be wrong if our assumptions are wrong

• Sustainability is achieved only when economy, society, and the environment overlap

1.3 - Energy and Equilibrium

1. First law of thermodynamics: principle of conservation of energy

   • Principle of conservation of energy: states that energy in isolated systems can be transformed but not created or destroyed

2. Second law of thermodynamics: states that energy is transformed through energy transfers

   • Entropy: a measure of the amount of disorder in a system

     • Refers to the spreading out of dispersal of energy

     • More energy = less order

     • When entropy is used to do work, some energy is always wasted as heat energy

   • Energy = work + heat (+other wasted energy)

• Efficiency: the useful energy, the work or output produced by a process divided by the amount of energy consumed being the input to the the process

  • Efficiency =  work or energy produced / energy consumed

  • Efficiency = useful output / input

    • TIP: multiply by 100% if you need the answer in a percentage

• Equilibrium: the tendency of the system to return to an original state following disturbance. At an equilibrium; a state of balance exists among the components of a system

  • Types of Equilibrium: static, steady state, stable, unstable

1. Steady-state equilibrium: a characteristic of an open system where there are continents inputs and outputs of energy and matter, the system remains in constant state

   • No long-term changes, however, small fluctuations occur in the short term

     

2. Static equilibrium: no change occurs over time. Most non-living systems are in a state of static equilibrium

   • This cannot occur in a living system, it can only occur in an isolated system

     

3. Stable equilibrium: the system tends to return to the same equilibrium after a disturbance

   

4. Unstable equilibrium: the system will return to a new equilibrium after a disturbance

• Feedback loop: when information that starts as a reaction in turn may input more information which may start another reaction

  • This is a way that the input is affected by the output. In a stable equilibrium, feedback returns the equilibrium to its original state.

  • In an unstable equilibrium, feedback returns the equilibrium to a different state

• Negative feedback loop: stabilises steady state equilibria, occur when the output of a process inhibits or reverses the operation of the same process in such a way to reduce change, counteracts deviation.

  • Returns back to its original state

  • Stabilising as they reduce change

• Positive feedback loop: will amplify changes and bring the system towards a new tipping point where a new equilibrium is adopted

  • Change a system to a new state

  • Destabilising as they increase change

  • Albedo: reflecting ability of a surface

• Resilience: the ability of a system to return to its initial state after a disturbance

  • If a system has low resilience it will enter a new state

  • Generally considered a good thing, for example, bacterium will not be affected from antibiotics which is not good

• Factors affecting ecosystem resilience:

  • Biodiversity increases resilience

  • Species that can shift their geographical range → more resilient

  • Fast reproductive rate means faster recovery

• An ecological tipping point: is a reached when an ecosystem experiences a shift to a new state

  • Significant changes occur in biodiversity and services it provides

  • Changes are long lasting and hard to reverse

• Lake eutrophication: nutrients added to a lake may not change much until enough nutrients are added to change its state

  • Occurs when bodies of water are overly enriched with minerals and nutrients which promotes the growth of algae

• Extinction of a keystone species: A keystone species within an ecosystem is fundamental to keeping the ecosystem stable and supported

  • Their extinction can negatively affect the ecosystem

• Coral reef death: if ocean acidity rises enough the reef coral dies and cannot regenerate

1.4 - sustainability

• Sustainability: the use of resources that allows full natural replacement of the resources used and full recovery of the ecosystems affected by their extraction

  • Sustainable development: development that meets the needs of the present without compromising the ability of future generations to meet their own needs

• Ecological overshoot: when a sustainable resource is exploited to its maximum

  • Replenishing the resources will take longer

  • This increased demand is due to level of overall consumption, per capita consumption

• Natural capital: natural resources that can produce a sustainable natural income of goods or services

  • Economics use the world “capital” ro describe the means of production. For example: Factories, tools, machines…

  • Used to create goods which provide income

• Environmental impact assessments (EIA): is a report prepared before a development project changes the use of lans. It weighs up the advantages and disadvantages of the development

  • Will qualify changes to microclimate, biodiversity, scenic and amenity value resulting from the changes

  • These measurements represent the “baseline study”

• Baseline study: an analysis of a current situation to identify the starting points for a project

• Ecological footprint (EF): the area of land and water required to sustainability provide all resources at the rate which they are being consumed by a given population

  • A model used to estimate the demands that human populations place on the environmental

    

1.5 - Humans and Pollution

• Pollution: the introduction/addition of a substance to the environment by human activity. This addition is considered harmful to the environment

  • Pollutants released by human activities: matter, energy, living organisms

  • Matter (gasses, liquids, solids) which is organic (contains carbon atoms) or inorganic

  • Energy (sound, light, heat)

  • Living organisms

• Primary pollutants: are active on emission (carbon monoxide) from the incomplete combustion of fossil fuels

  • Causes headaches, fatigue, and can kill

• Secondary pollutants: are formed by primary pollutants undergoing physical or chemical changes

• Point source and nonpoint source pollutants:

  1. Nonpoint course (NPS):

     • Release of pollutants from dispersed origins, example: exhaust gases from vehicles

     • Has many sources (hard to detect its origin)

     • Rainwater can collect nitrates which are used as fertilisers

     • Air pollution can be blown and mix with other chemicals

  2. Point source (PS):

     • Release of pollutants from a single site

     • Easier to locate pollution

     • Easier to manage and can be found more easily

• Persistent organic pollutant (POPs): a toxic environmental contaminant which requires special handling and disposal

  • Resistant to breaking down and remain active in the environment for a long time

  • Can cause significant harm, Health wise, due to the heavy pollution we are inhaling

  • High molecular weight

  • Not soluble in water

  • Highly soluble in fats and liquids (can pass through cell membranes)

• Biodegradable pollutants: do not persist in the environment and break down quickly. May be broken down by decomposer organisms or physical processes. Example: Light, heat

• Acute pollution: when large amounts of pollutants are released causing a lot of harm

• Chronic pollution: long term release of a pollutant but in small amounts

  • Often goes undetected for a long time

  • More difficult to clean up

  • Often spreads widely

• Pollution:

  1. Direct measurements of air pollution:

     • acidity of rainwater

     • amount of gas in the atmosphere

     • amount of particles emitted by a diesel engine

     • amount of lead in the atmosphere

  2. Direct measurements of water or soil pollution:

     • nitrates and phosphates

     • amount of organic matter or bacteria

     • heavy metal concentrations

  3. Indirect measurements of pollution:

     • Measuring abiotic factors that change as a result of the pollutant (oxygen content of water)

     • Recording the presence of indicator species, only found if the water is polluted or unpolluted

• How can pollution be managed?

  • By changing the human activity which produced it

  • By working to restore or clean up damaged ecosystems

  • By regulating or preventing the release of the pollutant

1. Human activity: promoting alternative technologies through

   • Controlling release of pollutant/release of pollutant into environment

   • Impact of pollution on ecosystems

   • Campaigns, education, community groups, governmental legislation, economic incentives/disincentives

2. Controlling release of pollutant/release of pollutant into environment:

   • Legislating and regulating standards of emission

   • Developing/applying technologies for extracting pollutant from emissions

3. Impact of pollutant on ecosystems: Clean up and restoration of damaged systems:

   • Extracting and restoration of damaged systems

   • Replanting/restocking lost or depleted populations and communities