IB SL ESS terms

EVS

a world view that shapes how individuals or societies precieve and respond to enviormental issues.

broad values

life goals, general principles towards the world that are informed by peoples beliefs and world views

specific values

judgment regarding natures importance in particular situations

value indicator 

quantitive measures and qualitative descriptors that reflect natures importance to people 

intrinsic value

the belief that something has value simple because it exists, not because its useful to humans, for example a tree in a forest

instrumental value

the usefulness an entity has for humans. The value comes from providing goods (food and water), services (decomposers processing waste), or opportunities for human development (knowledge or creative inspiration)

technocentrism

assumes all environmental issues can be resolved through technology

anthropocentrism 

humans are central to any decision being made, and them being the most important element of existence. 

ecocentrism

nature is important on its own, not just because it helps humans, but because all living things and ecosystems have value.

changes in perspective caused by…

influence by government or NGO’s

models

simplified representation of reality: used to understand how a system works and to predict how it will respond to change

evaluation of model points: advantages 

• allows scientists to simplify complex systems and use them to predict what will happen if there are changes to inputs, outputs or storages

• allows inputs to be changed and outcomes to be examined without having to wait a long time, as we would have to if studying real events

• allows results to be shown to other scientists and to the public and are easier to understand than detailed information about the whole system

evaluation of model points: disatvantages  

• may be very complex, and over simplified= less accurate

• different models show different effects using same data/different people interpret it in different ways

• many assumptions must be made about these complex factors, for example models like climate change may not be accurate

• models rely on the expertise of the people making them biased

systems def

set of interacting or independent components

systems include…

• can be open or closed

• have parts

• have connections between those parts

• have a function or purpose

• exhibit emergent properties

emergent properties 

characteristics that arise when smaller components combine to form larger systems. Interactions between components in systems can generate emergent properties.

emergent properties example

Nutrition cycles, food webs, climate regualtion.

emergent properties are possible when…

• each part has a specialized function

• similar parts are grouped together

• groups cordinate functions

• the whole can do things the individual parts cannot

regional ecosystems

networks of organisms and their environment within specific areas

diversity

surrounding varies habitats like forests, deserts and aquatic environmental

ecological balance

plays a key role in maintaining biodiversity and ecological health

human benefits

provides essential services including clean air, water and resources for development

global circulation 

the movement of air around the earth that spreads heat from the equator to the poles. It happens because the sun heats the earth unevenly, and the spinning of the earth affects how air moves 

environmental system contains:

• abiotic components ( water, sunlight, temp, air, soil, nutrients )

• biotic components ( plants, animals, fungi)

societal system contains:

• value systems

• economic systems

• social systems

systems diagrams consists of:

• storages

• flows

• procceses

aswell as

• inputs : energy/matter enters systems

• outputs : something produced at the end of the system

• storage: areas where energy or matter are accumelated

• flow: movement of energy or matter within a system from on location to another

• boundries: outside/ edge of a system

system diagram external factor

the systems external environment is not part of the system but can affect the system or be affected by the system

flow and storages difference 

flows can be adjusted more quickly than shortages, storages change slowly because flows take time to flow. 

flows and storages sum and outflows

• sum of all inflows to a storage is greater than sum of all outflows from a storage, then the level of storage will increase

• sum of all outflows from a storage is greater than sum of all inflows from a storage, then the level of storage will decrease

• if the sum of all inflows to a storage is equal to the sum of all outflows from a storage, then the level of the storange will not change

1st law of thermodynamics

energy cannot be created or destroyed, only changed from one form to another ex: absorbed by the plants for photosynthesis (a conversion of energy)

2nd law of thermodynamics

when energy is transformed, some of it becomes less useful, usually released as heat because of if this the total disorder (entropy) of a system and its surroundings always increases. ex: there is less energy as it moves through the system

entropy def

a measure of disorder or randomness in a system ex: it will naturally over time increase 

static def and example

there is no change overtime, doesnt apply to natural systems as there are no inputs or outputs so no change occurs ( always in balance ) ex: a pile of rocks, non living things

stable def and example

the system tends to return to the same equilibrium after a disturbance. ex: after running outside your body temp increases, you start sweating and return to a normal body temp

unstable def and example

the system returns to a new equilibrium after disturbance. ex: greenland glacier melting and not refreezing to return to the equilibrium

feedback loops

systems are affected by info from outside and inside the system

negative feedback def and example

• return it to its original state

• stabilizing as they reduce change

ex: human body temp

positive feedback

• change a system to a new state

• destabilizing as they increase change

• after tipping point, it moves away from equilibrium

ex: as the temp rises, the ice melts, the temp rises and causes more water, which goes down to the bed of the iceberg and causes more ice to melt

feedback mechanism def

a proccess in which a change in one part of a system causes changes in other parts, which then either amplify(increase) or dampen(reduce) the original

resilience and tipping points def

the resilience of a system measures how it repsonds to a disturbance, the more resilient a system, the more disturbance it can deal with. It is the ability of a system to return to its original state after a disturbance (more complex system = more resilient)

affects of resilience (increase)

• greater diversity of compnents/ species

• complexity of interactions/developed food webs

• establishment of keystone species

• larger storages/productive resources (ex: nutriens, water, sunlight, reproductive rates, biomass )

• larger size of the system

• strong negative feedback systems

• a steady state equilibrium/ balanced inputs and outputs

affects of resilience (decrease)

• strong positive feedback mechanism

• human impact degrading structure/diversity/abundance

• systems being close to a tipping point

factors that can affect resilience of an eco system:

• increase in biodiversity

• climate

• large ecosystems

• reproductive strategies

• human intervention

• size and number of storages

• genetic diversity (some number of species have a better chance to survive)

tipping points def

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

tipping points example

its the point where an ecosystem or earth system changes so much that it cant go back to how it was before ( like melting sea ice or coral reef colapse )

trophic cascade def:

when a change in one level of a food chain (like predators) causes big changes in the levels below it (like herbivours and plants) 

trophic cascade example

removal of the top predator (wolf). when the top predator is removed, the population of deer is able to grow unchecked, which causes over consumption of the primary producer.

ecosystem equilibrium def

a state of balance in an ecosystem where the inputs (like energy,nutriens) and outputs (like waste) are relativly stable overtime, and the populations of organism remain relativly constant around a long-term average. Open systems(inputs, outputs, and procces of energy matter).

albedo

measure of how much incoming solar radiation (sunlight) a surface refelcts back into space

natural capital 

a stock of natural resources and the ecosystems they comprimise. ex: forests, soil, minerals, fossil fuels, renewable or non-renewable

non profital

ecosystem services. ex: shade or pressence of trees.

global vs local

• local veiw point is normally better

• global ex: demand for salmon universally

sustainablity development 

meeting the needs of the present without compromising the ability of future generations to meet their own needs 

3 dimensions of sustainabilty

enviormental, social, economic/ governence

sustainable practices

renewable energy, sustainable agriculture, preserving and protecting biodiversity

Maximum sustainable youth graph and how long it takes to go back to normal example

• short term ex: agricultrue

• medium term ex: ground water (there until a certain extent)

• long term example: renewable resource (fisheries)

unsustainable development def

when present progress is at the expense of future generations

natural income def

the flow of goods and services. ex: timber, clean water, crops, fish and climate regulation (eurosion control, flood prevention) those resources generate annually for human use and well being. its the “interest” or yield from the natural capital. 

to be sustainable:

natural income must be the result of the sustainable management of renewable natural capital, allowing for the full replenishment of the resources exploited and recovery of ecosystems.

enviormental justice

laws to ensure that no group or community is made to bear a disproportionate share of the harmful effects of pollution

enviormental racism

• ex: union carbide gas release in bhopal, india, the gas leakage still has intoxicated waters 40 years later-

biocapacity 

capacity of a given biologically productive area to generate an ongoing supply of renewable resources and to absorb its resulting waste

ecological footprint

area of land required to sustainably provide all resources for population

ecological footprint depends on…

• population size

• consumption per capita

• cropland

increase biodiversity by…

importing recources 

strengths of ecological footprint

• popular symbol for raising awareness of environmental issues

• useful snapshot of the sustainability of a population’s lifestyle

limitations of ecological footprint

• does not include all info on the environmental impacts of human activities

• does not show types of resources only total resource