This is according to the influential WWF Living Planet Report 2008, which warns that humanity is consuming the resources provided by Earth’s natural systems much too fast.
Earth, it declares, is facing a looming ecological credit crunch and the current financial recession pales in comparison.
“Reckless consumption is endangering our future prosperity,” writes James Leape, the director general of WWF International, in the report.
“Yet our demands continue to escalate, driven by the relentless growth in human population and individual consumption. Our global footprint now exceeds the world’s capacity to regenerate by 30 percent. If our demands on the planet continue at the same rate, by the mid-2030s, we’ll need the equivalent of two planets to maintain our lifestyles.”
The report, produced with the Zoological Society of London and the Global Footprint Network and released every two years, notes that Earth’s capacity to support a thriving diversity of species, including humans, is limited.
Using an ecological footprint, which measures human demand placed on natural ecosystems, as well as the Living Planet Index (LPI), which reflects the state of the planet’s ecosystems using 2 000 species of mammals, birds, reptiles, amphibians and fish, the report shows humanity’s ecological footprint has more than doubled between 1961 and 2005.
The LPI for terrestrial species is down by 33 percent, freshwater species by 35 percent and marine species by 14 percent, with grasslands being hammered and dropping by 36 percent.
Chiefly to blame for these declines are land transformation, deforestation and the burning of polluting fossil fuels to generate energy.
“There’s been a consistent drop in terrestrial, freshwater and marine species,” said Morne du Plessis, CEO of WWF-SA, at the launch of the report in Sandton.
“The message [since the 2006 report] is fundamentally the same – the slide continues.”
The ecological footprint study shows that while global biocapacity – the area available to produce our resources and capture our emissions – is 2,1 global hectares per person, the average individual footprint worldwide is 2,7 global hectares, far exceeding Earth’s carrying capacity.
US citizens account for the largest: each requires an average of 9,4 global hectares, or nearly 4,5 planet Earths if the global population had US consumption patterns.
While the average individual footprint of South Africans is 2,1 global hectares per person, Du Plessis pointed out that SA was home to large imbalances between rich and poor, which “creates a biased perception of individual footprints”.
“Each person on Earth should be able to sustain their life with 2,1 hectares – everything above that is out of kilter,” he said.
Nearly 45 percent of the global ecological footprint is from energy production, including the burning of fossil fuels such as coal, oil and natural gas.
“We need to grow local industries in renewable energy technology as fast as we can,” said Richard Worthington, manager of WWF-SA’s climate change programme.
The report suggests strategies including renewable and low emissions “wedges” that could meet protected energy demands to 2050, with reductions in carbon emissions of up to 80 percent and measures to cut individual consumption.
Deon Nel, the manager of WWF-SA’s Living Waters partnership, said on average each person consumed 1,24-million litres of water a year – with a cotton T-shirt requiring 2 900 litres in its production.
“By 2025, people will be experiencing physical scarcity and will not have enough water to live.”
There was some hope for recoveries in populations of white rhinos and the southern right whale because of massive conservation efforts, added Du Plessis.
“We want to do the same for our ecosystems.”