Unit 1 Flashcards
An Isolated system exchanges
No matter or energy, they also do not exist naturally
In a closed system
Everything is recycled
A closed system exchanges
Only energy can move within the system and no matter
Boundary
A boundary is something that separates a system from its surroundings
Transfers occur
When energy or matter flows and changes location, but not state
An open system exchanges
Both matter and energy can move as inputs or outputs
Ecosystems are
open systems that exchange matter and energy with their environment
Transformations occur
When energy or matter flows and changes its state (chemical nature, state, energy)
1st law of thermodynamics
Principle of conservation (no energy lost or gained)
Strengths of models
Easier to work with than reality, Can be used to predict the effect of a change of input, Can be applied to other similar situations, Helps observe patterns on a much smaller scale, Can be used to visualise really small things
Weaknesses of models
Accuracy can be argued as it is only a simplified version of the model, If the assumptions we make are wrong, the model will then be wrong, Predictions may be inaccurate due to the argument in the first point
What is feedback?
The return of part of the output of a system as an input, so as to affect succeeding outputs
The 2nd law of thermodynamics
- “the total entropy of an isolated system always increases over time.”
- when two systems are combined the sum of their entropies will not be more than their final combined entropy
- the second law of thermodynamics “places constraints” on the transfer of heat energy and efficiencies of heat engines
- when two systems come together, they will reach a balance
Sustainability
The use and management of resources that allows for full natural replacement of the resources exploited and full recovery of the ecosystems affected by their extraction and use
Millenium ecosystem experiment
Funded by the UN in 2001, The MEA is a research experiment with the focus on the way in which ecosystems have changed over the last decades and predicts the changes that will occur.
Ecological overshoot
An ecological overshoot is when humanity has ‘overshot’ its sustainable level of resource exploitation
Natural income
The produce/goods/services created by the environment to provide humans in order to produce natural capital
Sustainable development
Sustainable development has been defined as “development that meets the needs of the present without compromising the ability of future generations to meet their own needs”
Entropy
Energy that is not used
Herbivores
Animals
3rd law of thermodynamics
Entropy of a system approaches a constant as temperature approaches 0
What is an environmental impact assessment ?
A report which discusses environmental factors considering a range of parties while analysing a potential project and predicting the ultimate environmental impacts as a result of the project
Carnivores
Humans
Natural capital
A term used for natural resources that can produce a sustainable natural income of goods or services