Unit 1 - Foundations of Environmental Systems and Societies (copy)

EVS

Environmental value systems

What are environmental value systems (EVS)

An environmental value system is a worldview or paradigm that shapes the way an individual, or group of people, perceives and evaluates environmental issues

what are the categories of EVS?

ecocentrics, anthropocentrics, technocentrics

What is the ecocentric world view?

• puts ecology and nature as central to humanity

• life-centered, respects the rights of nature and dependence of humans on nature

• less materialistic approach to life

• self-restraint

• self sufficiency in human societies

ecocentric categories

deep ecologists, self reliant soft ecologists

What is the anthropocentric world view?

• believes humans must sustainably manage the global system (through use of taxes, environmental regulation)

• human centered - humans are not dependent on nature but nature is there to benifit human kind

What is the technocentric world view?

• believes that technological developments can provide solutions to environmental problems

technocentric categories

technocentrics, cornucopians

cornucopians

• believe world has infinite resources

• through technology humans can solve any environmental problems + improve living standards

• free market economy

environmental managers

• believe humans have ethical duty to protect the earth

• believe that governments need to protect environment, and make sustainable economies

deep ecologists

• put more value on nature than humanity

• believe in biorights - all societies and ecosystems have an inherent value and humans have no right to interfere

nurturing value system

ecocentric

intervening or manipulative systems

anthropocentric and technocentric

types of systems

closed system, open system, isolated system

open system

exchanges matter and energy with its surroundings

closed system

exchanges energy but not matter, do not occur naturally on earth, however earth is a closed system

isolated system

does not exchange matter or energy, no such systems exist, however cosmos could be an isolated system

what does the biosphere consist of?

atmosphere, lithosphere, hydrosphere, ecosphere

all systems have …

• storages (of matter or enegry)

• flows (into, through and out of the system)

• inputs

• outputs

• boundaries

• processes

what is an energy transfer?

when the flow of energy or matter flows and changes location but not its state

what is an energy transformation?

when energy or matter flows and changes its state

types of energy transformations

• chemical to mechanical

• radiant to chemical

• electrical to thermal

what are models?

representation of a complex process, used to understand how a system works and to make predictions

advantages of models

• easier to work with

• can be used to predict the effect of a change of input

• can be applied to other situations

• patterns

• visualization of smaller/larger things

disadvantages of models

• accuracy is lost due to simplification

• if assumptions are wrong, model will be wrong

• predictions may be inaccurate

when is sustainability achieved?

environment, social and economic overlap

social factor (explain)

• standard of living

• education

• community

• equal opportunity

environmental factor (explain)

• natural resource use

• environmental management

• pollution prevention

economic factor (explain)

• profit cost savings

• economic growth

• R and D

economic-social

• business ethics

• fair trade

• workers rights

social-environmental

• environmental justice

• natural resources stwardship

• local and global

environmental-economic

• energy efficiency

• subsidies/incentives for use of natural resources

Energy in systems rely on…

the laws of thermodynamics

First law of thermodynamics

energy is neither created nor destroyed, therefore energy is constant (in any type of system), and can only be altered in form (through transfers and transformations)

Second law of thermodynamics

entropy of a system will tend to increase over time

entropy

spreading out or dispersal of energy

nature of equilibria

• steady state equilibrium

• static equilibrium

efficiency

defined as useful energy

efficiency formula (2)

• efficiency = energy produced / energy consumed x 100%

• efficiency = useful output / input x 100%

equilibrium definition

the tendency for a system to return to an original state following a disturbance

Steady state equilibrium characteristics

• applies to open systems

• more or less constant

• no long term changes

• system will return to its previous state

• continuous inputs and outputs of energy and matter

Static equilibrium characteristics

• no change over time

• stable

• when disturbed, creates new equilibrium

• non living systems

negative feedback

• returns system to its original state

• same state of equilibrium

• stabilising as they reduce change

positive feedback

• changes system to a new state

• new state of equilibrium

• destabilizing as they increase change

stable equilibrium

tends to return to the same equilibrium after a disturbance

unstable equilibrium

system returns to a new equilibrium after disturbance

resilience of systems

measures how a system responds to a disturbance

the more resilience …

the more disturbance the system can deal with, keep the same state

the less resilience …

the less disturbance the system can deal with, will enter a new state

factors affecting ecosystem resilience (7)

• more complex system, more resilience, as there are more interactions between species

• the greater the species the greater the chance that a species can replace another if one dies out

• the greater the genetic diversity within species, the greater the resilience

• species that can shift geographical ranges are more resilient

• the larger the ecosystem the more resilience

• climate affects resilience

• faster reproduction means faster recovery

tipping points

the minimum amount of change within a system that will destabalize it, causing it to reach a new state

characteristics of tipping points

• involve positive feedback

• threshold point cannot be precisely predicted

• the changes are long lasting

• the chances are hard to reverse

• there is a time difference between the pressures driving the change and appearance of impacts