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Wind turbine


Measuring footprints

What do Ecological Footprints consider?


Ecological footprints look at human activities. The table shows the types of activities that are usually considered. Each area is converted into an equivalent area of land or sea that is needed to support it. The total gives the ecological footprint.


The table shows activities that are considered when constructing a person's ecological footprint.

Growing crops

Food crops

Crops are grown for:

  • food

  • animal feed

  • fibres (e.g. cotton)

  • oil crops (e.g. sunflower oil)

About 1.3 billion hectares of arable farmland are available worldwide for the production of crops.

Grazing animals


Animals are produced for:

  • meat

  • hides (e.g. leather for clothing and shoes)

  • wool

  • milk

There are about 4.6 billion hectares of grazing land available worldwide.



Timber is used for:

  • fuel

  • building materials

  • paper production

There are about 3.3 billion hectares of forests worldwide.



Fish and other marine foods are eaten by humans and a lot is also used in animal feeds.

Most of the seas' productive area lies within a short distance of the coastline. This is just 8% of the total water surface on the Earth.



Housing, roads, industrial production and other human activities all take up land area. An estimated 0.2 billion hectares are taken up like this.

Burning fossil fuels


Burning fossil fuels produces carbon dioxide. This is taken in by plants during photosynthesis. The area of plants needed to take in the carbon dioxide produced by an activity can be calculated.

Industrial production

Industrial site

Modern life relies on many goods and each needs to be produced. This requires resources as well as energy.

Increased efficiency, recycling and re-using materials can reduce the ecological footprint.