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The Living Planet Index and Ecological Footprint : Tracking the State of
Global Biodiversity and Human Pressures on the Biosphere
Jonathan Loh
WWF International
Honorary Research Associate, Institute of Zoology, Zoological Society of London
Abstract
WWF’s Living Planet Report has been published biennially since 1998. It was
developed as an attempt to quantify and communicate the gravity of the crisis faced by the
earth’s biodiversity and the challenge for humanity to live within the capacity of the
biosphere. Two indicators have been used to measure the state of and pressure on the
earth’s ecosystems. The Living Planet Index (LPI) tracks the state of global biodiversity by
aggregating trends in thousands of populations of vertebrate species living in the world’s
terrestrial, freshwater and marine ecosystems, starting from a baseline set to 1.0 in 1970.
The LPI database has now been expanded to the extent that it is possible to produce subglobal LPIs on particular biomes, taxonomic groups, regions or countries. The Ecological
Footprint measures humanity’s demand on the biosphere through the consumption of
natural renewable resources and the burning of fossil fuels. It can be used to compare
countries, regions, or humanity as whole against the biological capacity of the earth. These
two indicators have been adopted by the Convention on Biological Diversity (CBD) to
measure progress towards achieving its target of reducing the rate of biodiversity loss by
2010.
Living Planet Report
The indicators discussed in this paper were developed for the WWF Living Planet
Report (see http://www.panda.org/news_facts/publications/living_planet_report/index.cfm)
over the last decade. The LPR began ten years ago as part of a campaign leading up to the
new millennium. Its aim was to attempt to quantify, monitor and communicate the
declining state of the world’s biodiversity and the growing human pressures on the
biosphere from the consumption of natural resources. The first LPR was published in 1998
and has since been updated biennially. The measure of the state of biodiversity is called the
Living Planet Index and was developed by the author and colleagues based at the World
Conservation Monitoring Centre specifically for the Living Planet Report. The indicator of
human pressure on the biosphere is called the Ecological Footprint, and was developed
originally by Mathis Wackernagel and colleagues and has been used and subsequently
modified in the Living Planet Report since 2000. The last report was published in 2006 and
was a collaborative effort with the Zoological Society of London, WWF’s partner now
working on the Living Planet Index, and the Global Footprint Network, based in Oakland,
California, which is responsible for producing the Ecological Footprint.
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The 2010 Biodiversity Target
In 2001, at a meeting of the Convention on Biological Diversity (CBD), 190 of the
world's governments adopted a target to “achieve by 2010 a significant reduction of the
current rate of biodiversity loss at the global, regional and national level as a contribution to
poverty alleviation and to the benefit of all life on earth”. This target was endorsed the
following year at the World Summit on Sustainable Development in Johannesburg. Such
public commitments mean that, for the first time, the public can hold its leaders accountable
for their success or failure in meeting measurable and quantifiable objectives on this critical
issue. WWF and other NGOs are monitoring their progress and, wherever possible,
contributing to the achievement of this target. Equally, they will not fail to point out where
nations are falling short of their stated aims and will continue to call for much-needed
action.
Focal Areas
Within the context of the CBD, governments agreed to monitor and report on progress
under seven focal areas relating to the overall 2010 target. These are:
1.
Status and trends of the components of biological diversity
2.
Sustainable use
3.
Threats to biodiversity
4.
Ecosystem integrity and ecosystem goods and services
5.
Status of traditional knowledge, innovations and practices
6.
Status of access and benefit-sharing
7.
Status of resource transfers
This paper focuses only on the first two of these focal areas.
2010 Target Indicators
For each of the seven focal areas, indicators have been selected. In reality, only a few
of the selected indicators are sufficiently well developed or have sufficient data available to
enable them to measure progress towards the focal area of the 2010 target. Some indicators,
therefore, have been chosen “for immediate testing” and others for “further development”.
Because the target explicitly calls for a reduction in the rate of biodiversity loss, the data
used to measure progress must go back many years prior to 2010, or preferably decades.
Only a few of the selected indicators currently have datasets available that allow changes
over decadal timescales to be measured.
Under the focal area 1, status and trends of the components of biological diversity, there
are good datasets for four of the selected indicators
• trends in the extent of selected biomes, ecosystems and habitats – although currently
time-series data at the global scale exist only for forests, and possibly coral reefs
• trends in abundance of selected species (Living Planet Index)
• coverage of protected areas, although this does not in fact measure the status of
global biodiversity but one of the responses to its decline, and
• changes in status of threatened species (Red List Index)
2
Under focal area 2, sustainable use, global-level time-series data exist only for the
ecological footprint.
The Living Planet Index
The Living Planet Index (LPI) is an indicator of the state of the world’s biodiversity; it
aggregates trends in thousands of populations of vertebrate species from all around world
into a single index, starting at 1.0 in 1970. Separate indices are produced for terrestrial,
marine and freshwater species, so the LPI can also be considered to be a measure of trends
in
ecosystem
health
for
Living Planet Index
different biomes
or
habitats. 1.4
Although
1.2
vertebrates
represent only a 1.0
fraction of all
known species, it 0.8
is assumed that
their population 0.6
LPI
trends are typical 0.4
95% CI
of
global
biodiversity as a 0.2
95% CI
whole.
0.0
1970
1975
1980
1985
1990
1995
2000
The LPI is based on trends in about 5,000 populations of nearly 1,500 species. It is
calculated as the average of three separate indices that measure trends in populations of 752
terrestrial species, 389 freshwater species and 310 marine species (see Table 1). Between
1970 and 2003 (the most recent year for which sufficient data are available) the LPI fell by
about 30%. This is also the case for the terrestrial, marine and freshwater LPIs, which
confirms that the earth is losing its biodiversity at a rate unprecedented in human history.
Table 1: No.s of species in the LPI
Species
Terrestrial Freshwater
Marine
Total
Fishes
0
111
129
240
Amphibians
2
75
0
77
Reptiles
14
25
7
46
Birds
531
164
121
816
Mammals
205
14
53
272
Total
752
389
310
1451
Temperate and Tropical Terrestrial LPIs
The decline in terrestrial species populations by about 30% between 1970 and 2003
masks a significant difference between species in temperate regions and species in the
tropics. While temperate species populations remained reasonably stable on average,
tropical species declined by more than 50%. This rapid fall in tropical species populations
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reflects the rapid conversion of natural habitat to cropland or pasture over the last fifty
years, driven ultimately by the growth in human population and increasing world demand
for food, fibre and timber. The conversion of natural habitat to farmland in temperate
regions, on the other hand, largely occurred long before 1970, and the consequent decline in
species populations is not therefore reflected in the temperate index. The LPI does not say
that the current state of biodiversity is worse in the tropics than temperate regions, but that
the trends over the last three decades have been worse.
Temperate and Tropical Terrestrial Indices
1.4
1.2
1.0
0.8
0.6
0.4
Temperate Index
Low CI
High CI
Tropical Index
Low CI
High CI
0.2
0.0
1970
1975
1980
1985
1990
1995
2000
National LPIs
LPI Canada Terrestrial, 1970-2003
With around
5,000
species 1.4
populations in the 1.2
LPI database it is
possible
to
1
analyze the data to
look at trends in 0.8
particular regions,
0.6
biomes
or
taxonomic group. 0.4
Birds
For
some
Mammals
countries, it is 0.2
LPI Canada Terrestrial
possible
to
0
analyze trends in
1970
1975
1980
1985
1990
1995
2000
biodiversity at the
national level, and this has been done for Canada and Uganda. Although they are very
different countries in size, climate and economy, the same methodology can be used to
produce a national LPI. The results illustrate the differences between the temperate and
tropical regions very well. The Canadian LPI shows no overall trend, although Canadian
birds have fared much better than Canadian mammals, while the Ugandan LPI shows a
dramatic decline, also worse for mammals than birds. While it is true to say that these
aggregated indices hide some species population trends that run counter to the national
average, for example declines in Canadian prairie grassland birds, these national LPIs
broadly reflect trends in biodiversity in temperate and tropical countries respectively. The
Ugandan LPI would suggest that Uganda will meet the 2010 target as there has been a
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LPI Uganda
1.4
All Species N = 35
1.2
Birds N = 9
Mammals N = 26
1
0.8
0.6
0.4
0.2
0
1970
1975
1980
1985
1990
1995
2000
significant
reduction in
the rate of
biodiversity
since
loss
1995. This is
probably
a
result
of
political
stability and a
consequent
reduction in
poaching of
large game
animals.
Red List Index
The Red List Index (RLI) is not used in the Living Planet Report, but worth mentioning
as a well-developed indicator with some global-level time-series data. The RLI is a
relatively new indicator which tracks the changes in threat status, as recorded in the IUCN
Red List of Threatened Species, across all species in a given taxonomic group. The IUCN
Red List places species into threat categories according to an assessment of extinction risk,
ranked from least concern through vulnerable, endangered and critically endangered to
extinct in the wild. The only taxonomic groups which have been comprehensively assessed
are birds mammals and amphibians. So far the Red List Index has been applied only to
birds and amphibians, but will soon be completed for mammals too. In order to give a
better indication of trends in biodiversity as a whole, the RLI is being applied to large,
random samples of species from a number of less well-known taxonomic groups, including
invertebrates and plants, but these will not be ready until all these groups have been
assessed for threat status at least twice. The RLI for birds, which has the most
comprehensive data for any taxonomic group, shows that over 2% of all birds species have
become more threatened (moved up to a higher extinction risk category) since 1988
whereas less than 0.5% have become less threatened (moved down a category).
Ecological Footprint
The ecological footprint measures the area of biologically productive land and sea
required to sustain the resource consumption of a given population. The world’s ecological
footprint tripled between1961 and 2003 to over 14 billion hectares, while world population
approximately doubled. It is composed of the cropland, grazing land, forest and fishing
grounds needed to produce food, fibre and materials; the urban land occupied by buildings
and infrastructure; and the biologically productive land that would be required to absorb the
carbon dioxide emitted from burning fossil fuels. The carbon footprint was the fastest
growing component from 1961 to 2003 and now comprises about half of humanity’s total
footprint.
Our demands on the biosphere can be compared with supply, or the earth’s biologically
productivity. About a quarter of the earth’s surface, or just over eleven billion hectares, is
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biologically productive. Humanity’s ecological footprint is therefore about 25 percent
larger than the earth’s biological capacity, or biocapacity, a situation described as
overshoot. Overshoot is, by definition, unsustainable, and will result in the deterioration of
resource stocks and increasing carbon dioxide concentrations in the atmosphere and ocean.
Another way
to
look
at
overshoot is on a
per capita basis.
Eleven
billion
hectares
of
biologically
productive space
divided between
more than six
billion
people
equates to less
than two hectares
per person. A
regional
breakdown of the
global ecological footprint shows that the North American footprint is about 9.4 hectares
per person, the EU’s is about 4.8 hectares per person, while the Asia-Pacific and African
per capita footprints are 1.3 and 1.1 hectares respectively. In the figure below the height of
each rectangle represents a region’s per capita footprint, and the width represents its
population. The area of the rectangle is proportional to a region’s total ecological footprint.
In order to achieve a sustainable future, in which humanity’s resource consumption remains
within the biological capacity of the earth, the world average per capita footprint must fall
below 1.8 hectares per person. However, this ignores future population growth, and ignores
the needs of other species which also depend on the earth’s productivity. Ultimately we
may have to live on less than one hectare of biocapacity per person. The challenge for the
coming century will be to reduce humanity’s global footprint and, at the same time,
enhance the biological productivity of the earth in order to sustain 10 million of our own
species, as well as ensure the survival of the myriad others with which we share this planet.
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