Think about your daily life and recount every item you use. Whether it be a tube of toothpaste or a trip on an aeroplane, all the ingredients and all the parts of those items come from the earth. Every time we use something, we are using a part of the earth. We also must remember that with everything we use, the earth also tries to absorb the pollution created when making those things. Sometimes we lose track of all the things we consume and what kind of impact it has on the earth. But there is a measurement that tracks how much we are consuming and if the earth can cope with the number of things we are consuming. This is the ecological footprint. But how does this relate to cities? Why is it important? What are the factors that affect the ecological footprint? Let's take a look at the ecological footprint of our cities...
Ecological footprint of cities definition
Firstly, let's define the ecological footprint. The ecological footprint measures the impact we have on the environment through the amount of land needed per year to provide food, water, energy, and services per person and absorb the waste generated. The unit used is global hectares per person, it is calculated that we can have 2.1 gha each before it becomes unsustainable for the earth. If we keep using more land, by 2030 we would need two earths to support us.
Unsustainable is something that cannot be maintained or continued at the same level or rate.
For reference, the area of one hectare is 100 m by 100 m square. It is close to an international union rugby field which is 1.008 ha. However a global hectare is not always the same area as a hectare, a hectare of land that is lush and has high rainfall will scale higher as a global hectare than a hectare of desert land.
By calculating the ecological footprint on the scale of cities we can start to see how each city is affecting the earth on a larger scale and how different cities are reacting to the size of their ecological footprint.
Factors of ecological footprint
The ecological footprint is calculated through the ratio of two factors, the demand for resources and the supply which is the earth's biocapacity.
Biocapacity is the earth's ability to regenerate and absorb the waste created by humans.
The demand is how much we consume and how much waste we create, whereas the supply is how much the earth can absorb the waste and regenerate resources.
For demand, the ecological footprint calculates the ecological assets that a population requires to produce the products they consume, such as fiber in clothes, timber for houses, and space for buildings as well as absorbing waste such as carbon emissions.
For the supply, the ecological footprint tracks the following six different productive surface areas on the earth, grazing land, cropland, fishing grounds, carbon demand on land, forest area, and built-up land. Grazing land is land that is used for animals to graze on to provide meat, dairy, leather, and wool. Cropland is the land that is used to grow crops for food for human consumption, and animal feed and to be used as oil and rubber. Fishing grounds are for catching fish and seafood. Carbon demand on land is the land where carbon emissions are absorbed by forests. Forest areas are the areas of forest that are used for timber, pulp, and fuel. Built-up land is land that is covered by houses, transportation, industrial buildings like factories, and reservoirs for hydropower.
Another popular measure that is seen as a footprint and can be confused with the ecological footprint is the carbon footprint. It also measures the impact on the environment as it calculates the amount of carbon dioxide produced. For example, how much carbon is emitted through transport, heating a home, and producing food.
Ecological footprint importance
The concept of the ecological footprint was created by William Rees, a Canadian ecologist. It was later developed further through the dissertation by Mathis Wackernagel who was a Swiss urban planner. Together they wrote 'Our Ecological Footprint' and the ecological footprint was seen as a way to show the sustainability of current lifestyles. It was in support of more sustainable production methods and consumption.
The importance of the ecological footprint is to understand how much nature we have, how much we use, and the impact humans are having on the environment. It is also a globally used measurement that shows the countries with unsustainable habits and the inequality of consumption of resources. The ecological footprint is able to quantify the effects of consumption that a population is having and make them aware of the impact.
Ecological overshoot day is the day when humans have consumed more than the earth can regenerate in a year. The date is determined by dividing the biocapacity of the earth by the ecological footprint and multiplying it by 365. The remainder of the days is seen as global overshoot. For 2022, the ecological overshoot day was July 28.
Ecological Footprint by country
The average size of an ecological footprint of a country is 3.17gha in 2022. The countries with the highest ecological footprint are firstly Qatar at 14.72 gha, secondly Luxembourg at 12.79 gha, and thirdly United Arab Emirates at 8.95 gha. The countries with the lowest ecological footprint are firstly North Korea at 0 gha then secondly DR Congo at 0.01 gha and thirdly Iran at 0.1 gha. Highly developed countries and high-income countries tend to have a bigger ecological footprint. Burning fossil fuels, high population, and smaller land areas can lead to a bigger ecological footprint.
Fig. 2 - Oil facilities in Qatar
Comparing ecological footprints with other countries can show which countries have a bigger impact than others. However, to show the impact it is having compared with the earth's capacity, we have to compare the ecological footprint with the biocapacity of the country.
When a country has a bigger ecological footprint than the biocapacity it is called a 'biocapacity deficit' and when the biocapacity is bigger than the ecological footprint it is called a 'biocapacity reserve'. The top countries that are biocapacity reserves are French Guiana, Suriname, and Guyana. The top countries that are a biocapacity deficit are Singapore, Reunion, and Israel.
Ecological footprint of cities example
Tracking a city's ecological footprint helps the government to manage the human impact on the environment. Local governments can help with making the ecological footprint smaller by promoting low-energy housing, making public transport efficient, developing green spaces, community gardens, and parks, and regulating waste through policy. They can also encourage individuals on lifestyle and behavioural changes, such as reducing waste and consumption, using public transport, and choosing sustainable energy.
There are examples of cities reducing ecological footprints.
- Tirana in Albania has the lowest ecological footprint as a city. It has focused on trying to reduce its ecological footprint by creating a greenbelt around the city for more green spaces, connecting existing green spaces, and stopping urban sprawl.
- Grodno in Belarus built a waste separation plant and is focusing on strengthening separation of different materials when recycling by providing the residents with new containers for the separate kinds of waste.
- Ulaanbaatar in Mongolia is improving the data collection and monitoring of the Air Quality Index as air pollution it was one of the cities with the most air pollution.
Greenbelt is a policy where no one is allowed to build houses or factories in the area of land with fields or parks around a city.
Fig. 2 - The Great Park in Tirana, a part of the greenbelt
Ecological Footprint of Cities - Key takeaways
- The ecological footprint shows the impact we have on the environment through the amount of land needed per year to provide food, water, energy, and services per person and absorb the waste generated. It is measured in the units of global hectares per person.
- There are six different productive surface areas that are considered when calculating the ecological footprint. They are grazing land, cropland, fishing grounds, carbon demand on land, forest area, and built-up land.
- The importance of the ecological footprint of cities is to have a measurement that all cities can use to see which cities have unsustainable habits and to understand the unequal consumption of resources.
- Countries such as Qatar, Luxemburg, and United Arab Emirates have the highest ecological footprints whereas North Korea, DR Congo, and Iran have the lowest ecological footprints.
- There are ways to make the ecological footprints of cities smaller through low-energy housing, making public transport efficient, developing green spaces, community gardens, and parks, and regulating waste through policy.
References
- Fig. 2 - Oil facilities in Qatar (https://commons.wikimedia.org/wiki/File:Oil_factories_in_Mesaieed_Industrial_Area.jpg) by Felipe Fonseca (https://www.flickr.com/photos/felipefonseca/) licensed by CC BY SA 2.0 (https://creativecommons.org/licenses/by-sa/2.0/deed.en)
- Fig. 3 - The Great Park, a part of the greenbelt in Tirana (https://commons.wikimedia.org/wiki/File:Tirana_from_South.jpg) by Albinfo (https://commons.wikimedia.org/wiki/User:Albinfo) licensed by CC BY SA 3.0,2.5,2.0,1.0 (https://creativecommons.org/licenses/by-sa/3.0/deed.en https://creativecommons.org/licenses/by-sa/2.5/deed.en https://creativecommons.org/licenses/by-sa/2.0/deed.en https://creativecommons.org/licenses/by-https://creativecommons.org/licenses/by-sa/1.0/deed.en)
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