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Ecological Footprint---An Important Tool in Our Quest for Sustainability

by Tin-chee Wu

Find out how big your footprint is

What is Ecological Footprint? An ecological footprint is a measure of the demands that people place on nature. More specifically, the ecological footprint measures how much biologically productive land and water area is required to produce all the resources a given population consumes and absorb the waste that is generated. By looking at human consumption and comparing it to nature's productivity, the ecological footprint provides a means of estimating the impact that individuals, communities, regions or countries have on nature.

It is an innovative method of measuring the impact of human activities on the environment first proposed by William Rees of the University of British Columbia.

How the Footprint is Measured?

The footprint is the biologically productive area required producing all the products a person, a community or a country consumes. The footprint of any individual, household, community or country considers all of the land and water that is used for crops, roads, grazing, fishing, buildings and for producing wood products, and organizes this information into six separate components (Energy Land, Crop Land, Pasture Land, Forest Land, Sea Space, and Built Area) to calculate a total footprint. Any of these resources may come from all over the world.

Why is the Measurement of Ecological Footprint Important?

Since Ecological Footprint Analysis asks how large an area of productive land (wherever that land may be located) is needed to sustain a population at current levels of technology and consumption. It is an indication of how much biologically productive area we would use while we are living on this planet, and whether our current level of resource consumption can remain sustainable.

The analysis also identifies those areas where the carrying capacity is being unfairly appropriated. Per person ecological footprint of various regions and countries can be compared in an international context to determine disparities between regions and countries.

Regions that have footprints that exceed the available bioproductive capacity within their territory can be said to have an ecological deficit. There resource demands are met by using the bioproductive capacity appropriated from other regions. Conversely, regions that have not appropriated all their local bioproductive capacity to support their domestic needs are said to have an ecological surplus.
The Global Ecological Deficit

When the demands of a community or region exceed the local ecological production, it means that these local areas alone cannot provide sufficient ecological services to satisfy the population’s current patterns of consumption. They have to rely on imported sources or deplete their own resource and ecological capital. This is called ecological deficit – a measure of the amount by which a region exceeds its local carrying capacity, an indication of an unsustainable rate of consumption. This deficit reveals the extent to which the region is dependent on external productive capacity through trade or appropriated resource flows.

But an ecological deficit on the global scale means that the planet itself is not sustainable.

In 2001, the Earth had an average of 1.8 global hectares of productive land to provide for each of the 6 billion people on the planet. The average global ecological footprint was 2.2 global hectares per person. However, while the footprint of the average African or Asian consumer was less than 1.4 global hectares per person, the average Western European's footprint was about 5.1 hectares, and the average North American's was about 9.2 global hectares.

Therefore, the world population is currently running a huge deficit with the Earth. The world population is using over 20% more natural resources each year than nature can regenerate---and this figure is growing each year.

Projections based on likely scenarios of population growth, economic development and technological change, show that humans will consume between 180% and 220% of the Earth's biological capacity by 2050. This means that unless governments take urgent action, human welfare, as measured by average life expectancy, educational level, and world economic product, will go into decline by 2030.

The Footprint of Nations 2004 Report concludes that the world's wealthiest nations are mortgaging the future at the expense of today's children, the poor, and the long-term health of the Earth. Through excessive consumption of non-renewable resources, a handful of countries are depleting global reserves at a faster rate than ever before. These problems are compounded as wealthy nations continue to grow their economies by exploiting the resources and economic potential of their impoverished neighbours.

Based on the assumption that 12 percent of all biologically productive space should be left undisturbed for other species, about 1.7 global hectares would be left for humans. This figure of 1.7 global hectares is then the “ecological benchmark” for comparing humans’ ecological footprints.

Reducing the current footprint to match this ecological benchmark will be more difficult in the future as the global population increases and further resource degradation occurs. Assuming on further ecological degradation, the amount of biologically available space will drop 1.1 global hectares per person once the world population reaches its predicted 10 billion, the Report concludes.

In its Living Planet Report 2004, the World Wildlife Fund estimated that between 1970 and 2000, populations of marine and terrestrial species fell 30 percent; that of freshwater species declined 50 percent. "This is a direct consequence of increasing human demand for food, fibre, energy and water," it said. These declines are indicators of the ecological stress that the planet is subjected to. It is alarming to reflect the fact that in 1960, the world used only 50 percent of what the earth could generate.

In fact, developed nations as a whole are now using the equivalent of the entire surface of the earth as their ecological footprint to sustain productivity, and even tapping into natural resource capital.

What Are the Determinants of the Size of the Ecological Footprint and the Ecological Deficit?

Three factors determine the size of the ecological footprint:

‧ The efficiency of the productions systems used to harvest renewable resources and deliver goods and services to consumers
‧ The level of consumption per person
‧ The number of consumers (total population).

On the other hand, the Earth’s biological capacity is determined by the health of the ecosystems. The difference between the footprint and the biological capacity determines if there is an ecological surplus or deficit.
Based on these four determinants, four broad strategies to reduce the ecological deficit can be found:

1. Production: improve the resource-efficiency with which goods and services are produced.
2. Consumption: consume resources more efficiently and reduce the disparity in per person consumption between high and low-income countries.
3. Population: control population size.
4. Ecosystem: protect, conserve and restore natural ecosystems and biodiversity to maintain biological productivity and ecological services.

What Can We Do?

Based on these broad strategies, the following measures should be adopted at the local, national and international levels so as to make cities, regions and the planet more sustainable. These are -

‧ Increase the efficiency of the production, distribution and consumption systems for energy and materials we currently use.
Wasting less energy and materials will mean lower demands for energy and materials. At the same time, less waste will be produced. Developing renewable energy production systems (solar, wind) and the reduction, reuse, and recycling of materials are examples of this approach. However, this approach alone does not tackle the problem of population growth---and no matter how efficient a system is, energy and materials are still consumed and wastes generated.
‧ Change our attitude. Over the long-term, a paradigm shift is needed for the human population to move away from the idea that wealth and materialism are required for a high quality of life.
‧ Among the high consumption/high footprint countries, a transition into sustainable modes of production and consumption and attention to social equity will not only reduce their own footprints, but will also improve the quality of life around the world. They will also provide a positive example for the developing countries to emulate.

High Energy Consumption is the Primary Cause of an Expanding Footprint
On a global scale, energy demand accounts for 55% of the global footprint. Other components of consumption contribute less to the footprint---these include the consumption of cropland (22 per cent), forest land (8 per cent), built area (3 per cent), pasture land (6.4 per cent), and sea space (6 per cent). Therefore, effective actions in wise energy consumption and production at both the household and community levels can have a significant effect on the footprint of communities.

The importance of tackling energy consumption can also be seen from a historic perspective. Between 1961 and 2001, the global energy footprint had increased over seven folds, whereas global population only doubled during the same time period. As a comparison, the global food, fibre and timber footprint only increased by 42%.

Within the energy consumption component, available Canadian statistics can be used as an indicator of where actions might be most effective. In Canada, energy demand accounts for 55 per cent of its footprint (the same percentage as the global average), with the largest portion consumed by industry (38 per cent), followed by transportation (35 per cent), residential (15 per cent) and commercial/business (12 per cent). Therefore, energy efficiency measures taken in the industrial and transportation sectors would be most effective in reducing the overall footprint.

Contribution of Both Resource Consumption and Population to the Total Footprint
Per person consumption level is not the only key factor that affects the total footprint at the regional or national level. Population is the other key factor.

When the world’s countries are categorized into two income groups, the high-income countries had a total footprint of 5.893 billion global hectares in 2001, even though they had a high per person footprint of 6.4 global hectares. On the other hand, the low and middle-income countries had a total footprint of 7.602 billion global hectares, even though they had a per person footprint of only 1.5 global hectares. Thus, despite the high per person footprints among these richer countries, aggregate regional footprints shows a different picture. Due to the population differences between regions, the Asia-Pacific region, home to 3.5 billion or nearly 60% of the global population, is found to be the region with the largest footprint.

The main implication of this observation is that even though resource consumption in higher income and higher consumption countries will have to be reduced in order to move toward a sustainable global footprint, the possibility of the more populous regions increasing their per person footprint and/or population could swamp any gains in the higher income countries. Population stabilization and the development of low-impact technologies for all countries to use are therefore also the keys to a smaller global footprint.

For Further Information:
World Wildlife Fund, 2004 Living Planet Report 2004 (http://www.panda.org)
World Wildlife Fund, 2002. Living Planet Report 2002 (http://www.panda.org)
Redefining Progress, 2004. Footprint of Nations 2004. (http://www.RedefiningProgress.org)
Federation of Canadian Municipalities, Ecological Footprints of Canadian Municipalities and Regions, 2004. (http://www.fcm.ca)