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Ecological Footprint---An Important Tool in Our Quest for
by Tin-chee Wu
Find out how
your footprint is
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
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
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
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
Contribution of Both Resource Consumption and Population to the Total
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
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
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)