What is an ecological footprint, anyway?

An ecological footprint is a calculation that estimates the area of Earth's productive land and water required to supply the resources that an individual or group demands, as well as to absorb the wastes that the individual or group produces.¹

As of 2006, it would take nearly one and a half Earths to generate all the resources humanity consumes and absorb all of our CO₂ emissions.²

It takes 1.5 Earths to generate all the resources humanity consumes

Humans demand resources of food, fuel, medicine, and energy. We need productive land to supply all of these, yet that land is being threatened by development of roads, dams, factories, and houses. Once land is developed, it usually cannot be returned to farm land because of the soil and chemicals released from development. By 2080 many areas within the developing world will face a 15 to 50% reduction in agricultural productivity due to increased CO₂ emissions and resulting climate change.

Areas in red are expected to have up to 50% fewer crops grown, while areas in pink are expected to have up to 15% fewer crops. Climate change, population growth, and ecological footprint are all connected to changing agriculture.³ Credit: Cline 2007.

Who is most affected?

People living in cities, towns, and villages all over the world have an ecological footprint. However, as you can tell from the chart below, industrialized countries like the United States and England have higher average ecological footprints than less developed countries.

Industrialized countries like the United States and England have higher average ecological footprints than less developed countries.

The three components of ecological footprint are food footprint, wood products footprint, and degraded land footprint.⁴

Food footprint: What we choose to eat every day has certain effects on the ecological footprint of our globe. Diets that are high in meat and dairy have the largest ecological footprint, because it takes more land to have animals graze than to grow crops.⁵  While a single hectare of land produces enough potatoes for 22 people to eat, that same hectare can support only 1 person to eat beef.⁶ In addition to this high intensity of land use, animals like cows produce methane, a greenhouse gas.

Cattle at Backburn Farm

Wood products footprint: Wood products include printing paper, newspaper, magazines, junk mail, wrapping paper, and cereal boxes. The average American uses seven trees a year in paper, wood, and other products made from trees. This amounts to about 2,000,000,000 trees per year.⁷

Paper being prepared for recycling at a facility in Poland.

Degraded land footprint: Land degradation involves the decline in productive potential of land, including its major uses (rain-fed, arable, irrigated, rangeland, forest), its farming systems, and its value as an economic resource.⁸ Major causes of land degradation are: land clearing and deforestation, agricultural mining of soil nutrients, urban conversion, irrigation, and pollution.⁹

Sunset Uranium Mine in the western United States. The land is in the process of being reclaimed, by eliminating environmental and health hazards caused by mining.¹⁰

Where are the consequences felt?

Biodiversity diminishes as ecological footprints grow. For example, by 2030, 90% of African great apes will be in danger due to development. See below for comparison maps; black indicates severe damage, red indicates serious damage, and green indicates some damage.

Fragmentation and destruction of Great Ape habitat in Central Africa, from the GLOBIO and GRASP projects. To see pictures and read more about chimpanzees, gorillas, bonobo, and orangutans, see the World Wildlife Federation’s page on Great Apes.

Why is ecological footprint important?

If we continue to demand and use more than the Earth can support, we will eventually use up available land and resources, especially drinking water. Diverse ecosystems will continue to lose species, which will negatively impact our world. In addition, conflict will likely erupt as resources become scarce.

Citations

¹ http://www.pbs.org/strangedays/glossary/E.html

² http://www.footprintnetwork.org/en/index.php/GFN/blog/

³ http://www.wri.org/map/change-agricultural-output-potential-2000-2080

⁴ http://bcn.boulder.co.us/basin/local/sustain6.htm

⁵ http://www.brass.cf.ac.uk/uploads/Frey_A33.pdf, page 6

⁶ http://www.who.int/nutrition/topics/3_foodconsumption/en/index4.html

⁷ http://www.recycling-revolution.com/recycling-facts.html

⁸ http://www.unu.edu/env/plec/l-degrade/D-Ch_2.pdf

⁹ http://soils.usda.gov/use/worldsoils/landdeg/degradation.html

¹⁰ http://commons.wikimedia.org/wiki/File:Sunset_Uranium_Mine_Wyoming.JPG