Look at the state of the Earth

Marian Wilkinson
Environment Editor
SMH
October 26, 2007

The most authoritative scientific report on the planet's health has found water, land, air, plants, animals and fish stocks are all in "inexorable decline" as 2007 became the first year in human history when most of the world's population lived in cities.

The United Nations' Global Environment Outlook-4 report, released in New York, reveals a scale of unprecedented ecological damage, with more than 2 million people possibly dying prematurely of air pollution and close to 2 billion likely to suffer absolute water scarcity by 2025.

Put bluntly, the report warns that the 6.75 billion world population, "has reached a stage where the amount of resources needed to sustain it exceeds what is available".

And it says climate change, the collapse of fish stocks and the extinction of species "may threaten humanity's very survival".

Launching the report, the head of the UN's Environment Program, Achim Steiner, warned that, "without an accelerated effort to reform the way we collectively do business on planet earth, we will shortly be in trouble, if indeed we are not already".

One of the most disturbing findings is that environmental exposures are now causing almost one quarter of all diseases including respiratory disease, cancers, and emerging animal-to-human disease transfer.

Pressure on the global water supply has also become a serious threat to human development as the demand for irrigated crops soars. The report estimates that only one in 10 of the world's major rivers reaches the sea all year round because of upstream irrigation demands.

Each person's "environmental footprint" has on average grown to 22 hectares of the planet but the report estimates the "biological carrying capacity" is somewhere between 15 and 16 hectares per person.

Critically, fish stocks, a key protein source for several billion people, are in crisis. About 30 per cent of global fish stocks are classed as "collapsed" and 40 per cent are described as "over-exploited".

The exploitation of land for agriculture has hugely increased as populations increase and living standards rise. A hectare of land that once produced 1.8 tonnes of crops in 1987 now produces 2.5 tonnes. But that rise in productivity has been made possible by a greater use of fertilisers and water leading to land degradation and pollution.

"The food security of two-thirds of the world's people depends on fertilisers, especially nitrogen," the report says. In turn, the nutrients running off farmland are increasingly causing algal blooms. In the Gulf of Mexico and the Baltic Sea these have created huge "dead zones" without oxygen.

The report estimates that all species, including animals and plants, are becoming extinct at rates 100 times faster than those shown from the past in fossil records. The main causes include land clearing for agriculture, over-exploitation and pollution. Of the major species assessed, 23 per cent of mammals and 12 per cent of birds are threatened with extinction.

Genetic diversity is also shrinking as just 14 animal species account for 90 per cent of all livestock production and 30 crops dominate global agriculture. But overwhelmingly, the report finds that climate change caused by greenhouse gas emissions poses the gravest danger to the future of the planet. The authors note "a remarkable lack of urgency" in tackling human-induced global warming and, in a criticism of the Australia and the US, it notes that "several highly-emitting countries have refused to ratify the global climate change treaty, the Kyoto Protocol".

Significantly, Mr Steiner said last night be believed the governments were "finally turning the corner" on dealing with climate change.

"The momentum on climate change in 2007 is nothing short of breathtaking", he said. "It is time to find the same sense of urgency on biodiversity and degradation, on fisheries and freshwater".

Mr Steiner noted important progress in some areas, cuts in air pollution in Europe and cuts to overfishing in the Pacific. And he stressed that the authors of the report insist that its objective "is not to present a dark and gloomy scenario but an urgent call for action".

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