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Ecological footprint analysis compares human demand on nature with the biosphere's ability to regenerate resources and provide services. Globally the ecological footprint is larger than the earth’s biocapacity (sometimes referred to as ‘carrying capacity’) by over 20% and this margin is growing.
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Ecological footprint
The Ecological Footprint is a useful measurement of humanity’s demand on the earth’s biocapacity in terms of the area of biologically productive land and sea required to provide the resources we use and to absorb our waste.
In 2003 the global Ecological Footprint was 14.1 billion global hectares, or 2.2 global hectares per person. The reason it is called a global hectare is because it has a measure of the world-average ability to produce resources and absorb wastes; the point being that different countries have different productivity rates.
The total supply of productive area, or biocapacity, in 2003 was 11.2 billion global hectares, or 1.8 global hectares per person.
The footprint of a country includes all the cropland, grazing land, forest, and fishing grounds required to produce the food, fibre, and timber it consumes. It also includes the land required to absorb emissions from the energy it uses, and to provide space for its infrastructure including roads and built areas.
People consume resources and ecological services from all over the world, so their footprint is the sum of these areas, wherever they may be on the planet.
Carbon footprint
Probably the best-known component of the Ecological Footprint is the Carbon Footprint. Carbon Footprint is the land required to absorb the C02 that is released from the burning of fossil fuels and other sources.
Separating the Ecological Footprint into its individual components demonstrates how each one contributes to humanity’s overall demand on the planet. Globally, the Carbon Footprint was the fastest growing component, increasing more than ninefold from 1961 to 2003.
Overshoot
Humanity’s footprint first grew larger than global biocapacity in the 1980s; this overshoot has been increasing every year since, with demand exceeding supply by about 25 per cent in 2003. This means that it took approximately a year and three months for the Earth to produce the ecological resources we used in that year.
How is it possible for an economy to continue operating in overshoot? Over time, the Earth builds up ecological assets, like forests and fisheries. These accumulated stocks can, for a limited period, be harvested faster than they regenerate. CO2 can also be emitted into the atmosphere faster than it is removed, accumulating over time.
For three decades now we have been in overshoot, drawing down these assets and increasing the amount of CO2 in the air. We cannot remain in overshoot much longer without depleting the planet’s biological resources and interfering with its long-term ability to renew them.
New Zealand’s Ecological Footprint
New Zealand’s ecological footprint in 2003 was 5.9 gha per capita which made us the ninth highest in the world.
However because of our sparse population and relative abundance of productive land New Zealand has not overshot it’s biocapacit. Our total biocapacity in 2003 was 14.9 gha so New Zealand has a biological reserve of 9.0 gha.
The table below breaks the footprint down into its component parts.
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