The term ‘sustainable development’ is defined as ‘development fulfilling the needs of current generations, without decreasing the possibilities for future generations to fulfil their needs’*. The main themes in sustainable development are ecological responsibility, economic efficiency and social well-being. The three possible goals of sustainable development are increasing economic efficiency, protecting and restoring ecological systems and improving human well-being, or a combination of the three. The maintenance of natural resources is a subject that often appears when sustainable development is considered.
A way to express the availability and use of natural in a quantitative way is the ‘Ecological Footprint’**. The ecological footprint of a defined group of people (for example a household, town or country) is the total surface area of biologically productive land and amount of water needed to produce all the goods and energy (food, energy and other materials) and needed to decompose the litter that is produced by these same people or compensate for it. Therefore the calculated ecological footprint is the total surface area of land that is required to maintain a certain lifestyle.
Fair Earth Share
If we want to say anything about sustainability, we should compare the available area and the area that is required. If the total area of productive land on earth is divided by the number of its inhabitants, there is 1.45 hectare productive land and 0.55 hectare fresh water available for each person. This is also called the ‘Fair Earth Share’. The exact size of this share differs among authors. Furthermore if the world population increases the available area per person will decrease.
The footprint is a measure for sustainability. Consumed goods and activities are taken into account when calculating the footprint. In this way an idea can be obtained of society’s sustainability on different scales (local, national and international). From calculations it appears that the lifestyle of people in Western countries causes a larger (between 3 and 6 hectares) footprint than the ‘Fair Earth Share’. This implies that the lifestyles in these countries have a negative influence on the available area of other countries and future generations. The lifestyles can be regarded as unsustainable.
When the concept of the ecological footprint is used in sustainable development one will try to increase the living standard of many people, while decreasing the total footprint at the same time**. There are different ways to achieve this:
- Increase the productivity per surface unity of land (e.g. terraces on mountain slopes or solar panels on roofs)
- A more efficient use of natural resources (eco-efficiency technologies, like energy saving light bulbs)
- Decrease the total consumption through a decrease of the population and a reduced personal consumption (e.g. take the car less often and recycle everything)**
The sustainable footprint – as different from the ecological footprint
In this project we do not work on the ‘ecological’ but on the sustainable footprint, because the ecological footprint model is too limited. It only looks at hectares and not at the way they are being changed. It makes a big difference if a field is used for organic farming or poisoned by chemicals or if a hillside is used for harvesting wood or completely deforested.
A really sustainable footprint…
We all leave ‘footprints’ behind. Mostly they disappear quickly, but some will exist for a shorter or a longer time. The most famous – and most sustainable – footprints are the footprints of pre-human creatures who walked 3,5 million years ago on wet volcanic ashes in Laetoli (Eastern Africa, now Tanzania). The footprints stayed for millions of years and were extremely valuable after they were found, because they tell us about our forefathers. The humanlike creatures did not mean that to happen, they would not even have understood anything of this, they were just running for their life, away from the dangerous volcano. From other people too we can sometimes find traces that can tell us about their life –archaeology can only exist by using these ‘footprints’. Thus waste left behind can also be a blessing… When somebody leaves a bronze or stone sculpture behind, he means to inform people afterwards to know about his or her existence. When somebody leaves behind other things he usually does not have that intention. But these traces often give just as much information. They can be ‘sustainable footprints’ as well. Not only remainders of buildings, works of art or tools give us information about human life, ecological aspects too can inform us about earlier human influence: landscapes and vegetation often bear the imprints of human culture. In this project we will be interested in the ecological footprints we leave behind but it is a good idea to make connections with historical or even archaeological aspects.
The role of the dodo
A well known and strong example is the dodo. This bird living on the island Mauritius died out because the Dutch sailors on their way to the far east caught them for meat. The bird was too slow to escape, and in the end left only some bones behind. In the 20th century biologists discovered on the island a species of trees that were all without exception more than 300 years old. Seeds were found but they never managed to grow. They were dependent on the dodo. This was proven by forcing the seeds through the throat of turkeys. After passing the alimentary system of these birds the seeds would grow. It is also possible to get this result by treating them with acid and sandpaper. Because the dodo became extinct this tree was also going extinct. The ‘sustainable footprint’ of the Dutch sailors was not only the disappearing of the dodo, but in the longer term also of this species of trees and probably of a number of insects and other animals depending on the bird and the tree. Perhaps there are more ecological changes as a result of the disappearing of the dodo.
Leaving positive footprints
A sustainable footprint can also be positive. Human influence often has enriched nature. An open landscape, with a rich variation of fields, meadows and forests, such as human beings have created in many regions of the world, carries a bigger biodiversity than an area covered with only forests – like western Europe was before human habitation. In most cases however human influence makes nature poorer.
Lasting (sustainable) footprints in nature
Examples of sustainability effects that you could use in your lessons or projects
- If species of plants or animals go extinct they are gone forever. Their possible products (think of medical use of still unknown plants) and/or their ecosystem are lost. Nobody knows what will be the result (think of the example of the dodo). Try to imagine whaty happens after deforestation or some other operation of this nature of your region
- When hillsides lose their forest cover the fertile soil is usually lost by erosion. It will last very long before the rocks have weathered enough to carry forest again (maybe thousands of years). On the Indonesian island Java the forests on the tops and upper mountainsides used to be sacred. It was not allowed to cut them. When in recent years people did cut them the valleys were in deep trouble with flooding etc. Calling these forests sacred was based on a intuitive deep ecological insight! Are traditional views perhaps more sustainable than modern views?
- A house built of natural materials like wood or bamboo can disappear without leaving a trace. Houses made of concrete stone or bricks can not, but the material can be reused when the houses have to be demolished. (But of course better keep them). Do we choose for the future archaeologist or for the ecology? What is sustainable building?
- Pesticides can stay in the soil or in the water for a long time. When they appear in the groundwater, they can (after a long time, and sometimes far from the place they were used) eventually appear in the drinking water. As long as they are in the groundwater nothing can be done. Nowadays most pesticides are less persistent than before, but often it is not clear what ecological effect they have before they disintegrate. It is more sustainable not to use them at all. How can we fight pests in a sustainable way?
- In organic agriculture people try to work in natural cycles: the fodder is grown in the same farm and the manure is used in the same fields. No synthetic chemicals are used. This type of agriculture does not leave any negative footprint. Is organic agriculture sustainable in the sense that it can feed all of humanity?
- Even the discussion about using genetic engineering can be used in this theme: it is possible to develop wonderful new variations but what will be the effects in the long run? How sustainable is this technology when we look at the ecological aspects? And what about the social aspects: what are the possibilities or problems for the farmers in the Third World?
** Wackernagel/Rees: Our ecological footprint (1996)
Working with the sustainable footprint
In this project we want to teach the students that they have the possibility to leave something positive behind for the world, that they can live in such a way that the world will be a little better than the world as they found it. But they also have to learn that, if we do not do anything to change our ways, we will leave a ‘negative’, a ‘bad’ footprint behind.We have at least partly the choice to make the world more or less sustainable by the way we live. A sustainable lifestyle should not leave a big (negative) footprint behind. In this project students can be stimulated to think about the question in what kind of world they want to live when they are grown up or old and about the life they like their children to live.Our way of living should at least make it possible that the people after us are not worse off than we are. Moreover students in the rich countries should realise that their way of life has influence on the life of people elsewhere and especially in the Third World. Think of the sweatshops where jeans, shoes etc are being made for the rich countries. The pay often is so bad that it is not possible to earn enough for a family. Therefore even young children have to work. In this project not only ecological sustainability is paid attention to, but also social and economical sustainability. It is best to connect these aspects in the different sub projects.
Scientific background information
An extensive article about the idea of the ‘footprint’ explaining the different aspects of the problems with sustainability of our modern world you find on http://www.voetafdruk.eu/nieuws/hoekstra-wiedmann-2014-environmentalfootprint.pdf