IB ESS Unit 1 - Foundations of Environmental Systems and Societies

environmental value system (EVS)

a world view or paradigm that shapes the way an individual or group of people perceive and evaluate environmental issues. This is influenced by cultural, religious, economic, and socio-political context.

ecocentric worlview

puts ecology and nature as central to humanity

anthropocentric worldview

believes humans must sustainably manage the global system

technocentric worldview

believes that technological developments can provide solutions to environmental problems

cornucopians

extreme technocentrists who see the world as having infinite resources to benefit humanity

environmental managers

moderate technocentrists who see the Earth as a garden that needs tending - the stewardship worldview.

biocentric worlview

see all life as having inherent value - value for its own sake, not just for humans

deep ecologists

put more value on nature than humanity. They believe in biorights - universal rights where all species and ecosystems have an inherent value and humans have no right to interfere with this

system

a set of inter-related parts working together to make a complex whole

open system

exchanges matter and energy with its surroundings

closed system

exchanges energy but not matter with its surroundings

isolated system

exchanges neither matter nor energy with its surroundings

transfer

occurs when energy or matter flows and changes location but does not change its state

transformation

occurs when energy or matter flows and changes its state - a change in the chemical nature, a change in state or a change in energy

systems approach

a way of visualizing a complex set of interactions which may be ecological or societal

model

a simplified version of reality that can be used to understand how a system works and predict how it will respond to change

1st Law of Thermodynamics

Principle of conservation of energy, which states that energy in an isolated system can be transformed but cannot be created nor destroyed

2nd Law of Thermodynamics

Energy is transformed through energy transfers. An increase in entropy arising from energy transformations reduces the energy available to do work.

entropy

a measure of the amount of disorder in a system

efficiency

the useful energy, the work or output produced by a process divided by the amount of energy consumed

negative feedback loops

Stabilizing systems that occur when the output of a process inhibits or reverses the operation of the same process in such a way to reduce change - it counteracts deviation

steady-state equilibrium

characteristics of open systems where there are continuous inputs and outputs of energy and matter, but the system as a whole remains in a more-or-less constant state

static equilibrium

no change over time

stable equilibrium

a system that tends to return to the same equilibrium after a disturbance

unstable equilibrium

a system that returns to a new equilibrium after a disturbance

positive feedback loops

Destabilizing systems which tend to amplify changes and drive the system toward a tipping point where a new equilibrium is adopted.

tipping point

when an ecosystem experiences a shift to a new state in which there are significant changes to its biodiversity and the services it provides.

sustainability

the use and management of resources that allows full natural replacement of the resources exploited and full recovery of the ecosystem affected by their extraction and use

sustainable development

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

natural capital

natural resources that can produce a sustainable natural income of goods or services. e.g. forest (natural capital) provides timber (natural income)

ecological footprint

the area of land and water required to sustainably provide all resources at the rate at which they are being consumed by a given population

pollution

the addition of a substance or an agent to an environment by human activity, at a rate greater than at which it can be rendered harmless by the environment, and which has an appreciable effect on the organisms within it.

primary pollutant

pollutants which are active on emission

secondary pollutant

pollutants which are formed by primary pollutants undergoing physical or chemical changes

non-point source pollution

pollution which is released from numerous, widely dispersed origins. May have many sources making it virtually impossible to detect exactly where it is coming from.

point source pollution

release of pollutants from a single, clearly identifiable site.

Persistent organic pollutants (POPs)

Chemicals, often manufactured as pesticides in the past, which are resistant to breaking down and remain active in the environment for a long time.

Biodegradable pollutants

Pollutants which do not persist in the environment and break down easily.

Acute pollution

large amounts of a pollutant are released over a short period of time, causing a lot of harm

chronic pollution

The long-term release of a pollutant, in small amounts.