IB EXAM - ENVIRONMENTAL SYSTEMS & 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 worldview

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.

water budget

a quantative estimate of the amount of water in different storages - the distribution of water on Earth - 97% salt, 3% fresh - mostly in ice caps and glaciers (68.7%)

Blue Planet

Earth's name due to the fact that 70% of Earth is covered with water

turnover times

how long it takes for a molecule of water to enter and leave that part of the hydrological system

(e.g. 37,000 years in the ocean; 16,000 years in ice caps; 300 years in groundwater; 12-20 days in rivers; 9 days in the atmosphere)

renewable water storages

atmospheric water and rivers - quickly replenished

middle ground (neither renewable or non-renewable) water storages

groundwater aquifers - take a long time to replenish (currently used unsustainably)

non-renewable water storages

oceans and icecaps - they would take 100s of years to replenish if used

the hydrological cycle

energy from solar radiation and the force of gravity drive the water cycle - which drives the world's weather systems

precipitation

rain

evaporation

liquid water changing state to gaseous water (water vapour)

evapotranspiration

the water lost by plants (especially trees in rainforests) through their leaves

infiltration

water sinking below the surface into the soil

surface run-off

water which does not infiltrate the soil, bu flows along the surface

condensation

gaseous water (water vapour) which turns to liquid - especially in clouds causing rain

advection

wind-blown movement

aquifer

groundwater - the water which is stored in permeable rocks between layers of impermeable bedrock - often drilled down into to create wells

withdrawals (a human effect on water systems)

water is used for domestic use, irrigation in agriculture and in industry

discharges (a human effect on water systems)

the addition of pollutants to water

e.g. chemicals from agriculture, fertilisers, sewage.

changing the flow (a human effect on water systems)

building roads and channeling water rivers underground or in concreted areas

canalising - straightening large sections of rivers

use of dams, barrages and dykes; making reservoirs

diverting flow (a human effect on water systems)

many rivers are led way from important/urbanised areas,

some are led to dams to increase storage

ocean currents

movements in the sea both vertically and horizontally - move in specific directions, and some have names

surface currents

the movement of the ocean in the upper 400m - movement is due to wind

deep water currents

aka thermohaline currents - caused by difference in temperature and salt concentration

hot water rises (less dense) - cold water sinks

water with a high salt concentration sinks (is more dense) - lower concentrations rise

the great oceanic conveyer belt

the huge oceanic currents which circulate the globe

climate

the weather patterns experienced by different locations

El Nino Southern Oscilations (ENSO)

trade winds weaken allowing warm waters to spread to the east
this causes warm air to rise in the middle of the Pacific
cold mineral rich water is pushed up in the middle of the Pacific causing fish to be found too far off shore for fishermen in small boats

Neutral phase (ENSO)

trade winds blow warm air and water from the east to the west Pacific

cold water is drawn up from the deep on the western coasts of the americas (carrying nutrient rich waters = fertile waters - many fish)

air rises in the western Pacific and circulate back to the eastern Pacific

La Nina (ENSO)

an overdrive of the neutral phase - the trade winds blow harder - the temperature difference between east and west increases

more evaporation and therefore rain in the west

the Walker Circulation

the winds which travel west across the Pacific, rise in the west (eastern coast of Australia), travel east again, and sink in the east (Western coast of the Americas)

saline

salt water - this is the majority of Earth's water

desalination plants

removing salt from saline water to create potable (drinking) water

requires a lot of energy - extra salty water is often released back into the ocean damaging sea-bottom ecosystems (the salt water sinks)

water crisis

the UN's term to describe the situation we are in today where up to 40% of humans alive do not have access to sufficient clean water

domestic water use

water used for drinking, washing and cleaning at home

agricultural water use

water used for irrigation (water for crops) and for animals to drink

industrial water use

water used for processes such as machine cooling, manufacturing and mining

20 litres of 40 litres?

the WHO (World Health Organisation) and Agenda 21 state that every human should have/needs access to this much water per day (on average)

much of the world has far less - other considerably more

water scarcity

how much water we have and how we use it

there may be enough water in an area, but then it is diverted for non-domestic use

sources of freshwater

underground aquifers

surface freshwater - rivers, streams, reservoirs and lakes

aquifer

a layer of porous rock sandwiched between two layers of impermeable rock

refills where the porous rock meets the surface as water infiltrates

(flow can be as little as 1-10m per centrury - therefore refilling is extremely slow)

aquitard

the impermeable rock above (upper) and below (lower) the permeable rock forming an aquifer

grey water

water used in the home for cleaning, brushing teeth, showering etc

often is not really dirty, but drains the same way as sewage

black water

sewage - the water containing human waste - may carry disease-causing bacteria or parasites

water wars

the conflict caused by dispute over water sources - often when sources are shared e.g. Israel, Gaza and Egypt

marine ecosystems

oceans, mangroves, estuaries, lagoons, coral reefs, deep ocean floor

very diverse and have high stability and resilience

continental shelf

the extension of the continents under the seas and oceans - creates shallow water

important because:
upwellings bring nutirent-rich water to continental shelf
higher light penetration/insolation
countries can claim it as theirs to exploit and harvest

UNCLOS

The UN Convention on the Laws of the Sea - in 1982 they designated the continental shelf as belonging to the country from which they extend

phytoplankton

single-celled organisms that can photosynthesis and are the most important producer in in the oceans, producing 99% of primary productivty - crucial in supporting oceanic food webs

zooplankton

single-celled animals which feed off of phytplankton and their waste - crucial in supporting oceanic food webs

DOM

dead organic matter

waste created by living organisms as they grow and die

benthic

organisms living on or in the sea bed

pelagic

organisms living surrounded by water from above the sea bed to the surface

fishery

when fish are harvested in some way - includes capture of wild fish and aquaculture (fish farming)

90% is marine - 10% is freshwater

more than 70% of world fisheries are fully exploited, in decline, seriously depleted or too low to allow recovery

FAO

Food and Agriculture Organisation

aquaculture

the farming of aquatic organisms in both coastal and inland areas involving human intervention in the rearing process to enhance production (FAO)

benefits of fish

high in protein, contains important lipds (fats and oils), low in bad fats, provides

on average, people eat 20 kg of fish and only 8 kg of meat

vegetarian farmed fish

solution to sustainable aquaculture - the United States Department of Agriculture has proven that there are eight species of carnivorous fish which can gain enough nutrients on a diet excluding other fish

China's production of farmed fish

62% of all farmed fish - mostly carp or catfish - often grown in rice paddies (DOM and waste provides nutrients for the rcie)

rice - fish farming

a system whereby fish are reared in rice paddies - the fish eat insect larva and algae and produce waste which the rice uses as fertiliser

the tragedy of the commons

is an economic theory of a situation within a shared-resource system where individual users acting independently according to their own self-interest behave contrary to the common good of all users by depleting that resource through their collective action