John Yeld

EARTH cannot sustain its human population of just more than seven billion at current consumption rates – and unless people fundamentally change their behaviour, even two Earths won’t be enough by as soon as 2030.

That’s the harsh message in the 2012 edition of the World Wide Fund for Nature’s (WWF) Living Planet Report, the leading biennial analysis of the health of the planet and of the impact of human activity.

The new edition was released this week, and its key finding is that humans’ current demands significantly exceed the planet’s capacity to sustain them.

“We are living as if we have an extra planet at our disposal. We are using 50 percent more resources than the Earth can sustainably produce and unless we change course, that number will grow fast – by 2030, even two planets will not be enough,” says Dr Morné du Plessis, chief executive of the SA branch of WWF.

The report uses a global living planet index, or biodiversity index, to measure changes in the health of the planet’s ecosystems by tracking 9 000 populations of more than 2 600 species. This shows an almost 30 percent decrease since 1970, with the tropics being hardest hit with a 60 percent decline in less than 40 years.

Also on a downward trend is earth’s “ecological footprint”, another key indicator used in the report to illustrate how human demand for natural resources has become unsustainable.

This is a measure of how much biologically productive land and water an individual, population or activity requires to produce all the resources consumed and to absorb the waste generated, using prevailing technology and resource management practices.

SA has an ecological footprint of 2.59 a person per hectare, of which the biggest component is from carbon (fossil fuel) use.

The report also offers solutions, outlining 16 priority actions needed to reverse the declining Living Planet Index and bring ecological footprints within the limits of a single planet.

“We can create a prosperous future that provides food, water and energy for the nine or perhaps 10 billion people who will be sharing the planet in 2050.

“Solutions lie in such areas as reducing wasteful consumption, smarter water management and using renewable sources of energy that are clean and abundant, such as wind and sunlight,” says Du Plessis.

l See http://www.wwf.org.za/ media_room/publications/lpr/