Evaluate our ecological footprint as a measure of the relationship between

population size and resource consumption.

What is a resource?

Is this a resource?

resources…….

Resources are things people need to live and do their workTypes of resources: basic, Renewable, non renewable, primary,

secondary, physical1. Will run out in the future non renewable2. Won’t run out as they can be reusedrenewable3. Comes straight out of the ground or oceanPrimary4. Is made or manufactured by peopleSecondary5. Can’t live without themBasic6. Comes from naturephysical

How can we measure resources used by people?

An ecological footprint is….

• The theoretical measurement of the amount of land and water a population requires to produce the resources it consumes and to absorb waste, under its prevailing technology

• Measured in global hectares

http://www.youtube.com/watch?v=EjyrAHzthTo

To calculate this we use…….• Arable land – amount of land used for growing crops• Pasture land – feeding farmed animals• Forests – for fuel, furniture, and ecosystem stability• Oceans – viability/ supply of food, health• Infastructure needs – eg.transport, factories, housing• Energy costs – land needed for absorbing CO2 and

other energy wastes(doesn’t include species extinction or pollution yet!)

Ecological Debtors & Creditors

• List 5 debtors and 5 creditors: how do you know this?

The ecological footprint of a place may change over time with population changes….

Increase in footprint due to:• Development• Consumption• Diet change (eg. vegetarian - meat eating in India)Decrease in footprint due to:• Government policy such as pollution laws or

renewable energy policies• Economic recession reduces consumption• High cost of fuel reduces consumption

Biological Capacity: Biocapacity

• The capacity of a productive area to generate these resources and to absorb waste.

• UNSUSTAINABILITY occurs when the ecological footprint exceeds biocapacity

International variation in Footprint…