The destruction of 70% of the natural world in 30 years, mass extinction of species, and the collapse of human society in many countries is forecast in a bleak report by 1,100 scientists published yesterday.
The Global Environment Outlook, compiled for the UN, charts the environmental degradation of the last 30 years since the first world environment conference in Stockholm in 1972 and looks forward to how the world might look by 2032.

Unless the world changes its current "markets first" approach, the increase in building of roads, power lines, airports and other infrastructure will disrupt wildlife breeding patterns and wipe out species, particularly in coastal areas where most human settlement is concentrated. Forests continue to disappear at an alarming rate and 10% of land on which to grow food is lost because of soil degradation.

More than half the world will be afflicted by water shortages, with 95% of people in the Middle East with severe problems and 65% in the rest of Asia and the Pacific.

The Mediterranean coast will come under special pressure through urban growth, inadequate waste water treatment, tourism and intensively farmed crops.

But the report says it need not be like that. In richer countries water and air pollution is down, species have been restored to the wild, and forests are increasing in size.

The 450-page analysis was published in London yesterday partly to shock world leaders into taking seriously the World Summit on Sustainable Development, to be held in South Africa in August.

The last preparation meeting for the conference takes place in Bali, Indonesia, next week, and many doubt that the agenda reflects the urgency of the problem.

The report paints four possible futures for the world, including the current pattern of free trade and short term profit at the expense of the environment, which leads to disaster.

In a second, equally dangerous scenario, security considerations dominate with fear of terror and mass immigration into rich areas. It involves a world split into rich and poor, with freedom of movement and democracy restricted and rich enclaves like Europe and North America with barriers keeping out the poor and desperate.

A third offers a strong policy based option where governments try to protect the environment with international treaties with varying degrees of success. The fourth, where all decisions are based on sustainable development rather than short time gain and greed, is the blueprint favoured by the report.

Klaus Toepfer, the UN Environment Programme executive director, called for concrete actions and an iron political will to change the existing pattern. "Without the environment there can never be the kind of development needed to secure a fair deal for this or future generations. It would be disastrous to ignore the picture painted."

He said that under the "markets first" scenario the environment and humans did not fare well. "The human footprint grows, inflicting increasing damage.

"We now have hundreds of declarations, agreements, guidelines and legally binding treaties designed to address environmental problems and the threats they pose to wildlife and human health and well being. Let us now find the political courage and innovative financing needed to implement these deals and steer a healthier, more prosperous course for planet Earth."

Tough action
Margaret Beckett, the environment secretary, who is going to Bali, which has been painted as a junket for ministers and civil servants, said it was vital to make progress to set a proper agenda for action for the Earth summit.

The key aims for the meeting were to make progress on issues such as clean water, energy supply and food security for developing countries. She said tough action was needed now to avoid potential environmental disaster in the 2030s. "There may not be a world worth living in. History will see it as a tragic lost opportunity if we fail to meet this challenge," she said.

Although the report paints a dismal picture of the last 30 years, it points to some successes for treaties. The hole in the ozone layer is at a record size, but the repair of the damage is forecast to begin by 2032 because the use of ozone depleting chemicals is being phased out.

Mr Toepfer said that he hoped that George Bush would come to the Johannesburg summit to pledge support for a different world, including plans for a World Environment Organisation, and concrete projects like using renewable energy to give development hope to two billion people without electricity. There was a plan for the complete electrification of Africa with renewable supplies.

But the report says time is short. Land degradation, because of human activity, is already causing a crisis in agricultural production in some areas. For example in Iraq, because of bad irrigation practices, 30% of arable land has been abandoned because of salt contamination. A water crisis is developing across the whole of the Arab world as ground water is pumped out faster than rain can replenish it. Seawater is increasingly being drawn into underground freshwater supplies. For example, in Madras in India salt has poisoned fresh supplies seven miles inland.

In Latin America and the Caribbean, home of 25% of the world's forest cover and 178 regions of special biodiversity, the situation is already critical in 31 of them. "Biodiversity is constantly under threat from habitat loss, land degradation, land use change, deforestation and marine pollution," the report says.

Tony Juniper, director designate of Friends of the Earth, said: "This report poses a stark choice between destructive policies based on global market forces or embracing sustainable development. Meeting the needs of billions of poor people while protecting the environment is the great challenge posed to political and industrial leaders by this report. Delaying action is no longer an option. The Johannesburg summit must develop the necessary change in direction."

Counting the cost

The bad news
· In 30 years 70% of the Earth's surface will be suffering severe impacts of man's activities, destroying the natural world with roads, mining and cities


· 1,183 species of birds, around 12% of the world's total, and 1,130 species of mammals, about a quarter, are threatened with extinction


· One third of the world's fish stocks are depleted or overexploited


· Concentrations of carbon dioxide in the atmosphere could double by 2050. The number of people affected by weather related disasters has risen from 147 million a year to 211 million in 10 years


· There are 2.2 billion more mouths to feed than in 1972, and there will be another 2 billion in 30 years


· Already 40% of the world is short of fresh water, in 30 years this will rise to 50%. In west Asia this rises to 90%


· At least 15% of the Earth's surface is already degraded by human activities


· Overgrazing causes 35% of soil degradation, deforestation 30%, agriculture 27%


· More than a billion urban dwellers, mostly in Africa, Asia and Latin America, live in slums. Another billion people will be living in cities by 2010


· Half the world's rivers are seriously depleted and polluted. About 60% of the 227 biggest are disrupted by dams and other engineering works
· There are 4 billion cases of diarrhoea causing 2.2 million deaths a year


· 2 billion people are at risk from malaria, and 2 million die a year


· Contaminated shellfish causes an estimated 2.5 million cases of infectious hepatitis annually, resulting in 25,000 deaths


· A fifth of the world's population is responsible for 90% of consumption.Two thirds of the population, about 4 billion people, live on less than $2 a day


And the good
· The hole in the ozone layer is being repaired because of an 85% reduction in use of harmful chemicals in 114 countries


· The number of people with improved water supplies increased from 4.1 billion to 4.9 billion in the last 10 years


· About 10% of the Earth, 12.18m hectares, is in protected areas like national parks, five times as much as 30 years ago


· A moratorium on commercial whaling since 1986 is allowing species to recover


· The amount of water abstracted for public supply in western Europe fell by 10% in 10 years because of efficient use


· Emissions of most air pollutants in Europe have declined since the early 80s