By Jonathan Amos
BBC News science reporter
The most comprehensive survey ever into the state of the planet concludes that human activities threaten the Earth's ability to sustain future generations.
Millennium Goals, such as the halving of world poverty by 2015, are off target
The report says the way society obtains its resources has caused irreversible changes that are degrading the natural processes that support life on Earth.
This will compromise efforts to address hunger, poverty and improve healthcare.
The Millennium Ecosystem Assessment (MA) was drawn up by 1,300 researchers from 95 nations over four years.
It reports that humans have changed most ecosystems beyond recognition in a dramatically short space of time.
The way society has sourced its food, fresh water, timber, fibre and fuel over the past 50 years has seriously degraded the environment, the assessment concludes.
And the current state of affairs is likely to be a road block to the Millennium Development Goals agreed to by world leaders at the United Nations in 2000, it says.
"Any progress achieved in addressing the goals of poverty and hunger eradication, improved health, and environmental protection is unlikely to be sustained if most of the ecosystem 'services' on which humanity relies continue to be degraded," the report states.
"This report is essentially an audit of nature's economy, and the audit shows we've driven most of the accounts into the red," commented Jonathan Lash, the president of the World Resources Institute.
"If you drive the economy into the red, ultimately there are significant consequences for our capacity to achieve our dreams in terms of poverty reduction and prosperity."
The MA is slightly different to all previous environmental reports in that it defines ecosystems in terms of the "services", or benefits, that people get from them - timber for building; clean air to breathe; fish for food; fibres to make clothes.
The study finds the requirements of a burgeoning world population after WW II drove an unsustainable rush for these natural resources.
Although humanity has made considerable gains in the process - economies and food production have continued to grow - the way these successes have been achieved puts at risk global prosperity in the future.
"When we look at the drivers of change affecting ecosystems, we see that, across the board, the drivers are either staying steady or increasing in severity - habitat change, climate change, invasive species, overexploitation of resources; and pollution, such as nitrogen and phosphorus," said Dr William Reid, the director of the MA.
More land was converted to agriculture since 1945 than in the 18th and 19th Centuries combined. More than half of all the synthetic nitrogen fertilisers - first made in 1913 - ever used on the planet were deployed after 1985.
The MA authors say the pressure for resources has resulted in a substantial and largely irreversible loss in the diversity of life on Earth, with some 10-30% of the mammal, bird and amphibian species currently threatened with extinction.
The report says only four ecosystem services have been enhanced in the last 50 years: increases in crop, livestock and aquaculture production, and increased carbon sequestration for global climate regulation (which has come from new forests planted in the Northern Hemisphere).
Two services - fisheries and fresh water - are said now to be well beyond levels that can sustain current, much less future, demands.
The assessment runs to 2,500 pages and is intended to inform global policy initiatives. In many ways, it mirrors the work of the Intergovernmental Panel on Climate Change (IPCC) which, by bringing together hundreds of scientists in a peer-reviewed process, has driven efforts to slow global warming.
"The MA is a very powerful consensus about the unsustainable trajectory that most of the world's ecosystems are now on.
MA - ASSESSMENT OVERVIEW
Humans have radically altered ecosystems in just 50 years
Changes have brought gains but at high ecosystem cost
Further unsustainable practices will threaten development goals
Workable solutions will require significant changes in policy
"There will undoubtedly be gainsayers, as there are with the IPCC; but I put them in the same box as the flat-Earthers and the people who believe smoking doesn't cause cancer," said Professor Sir John Lawton, former chief executive of the UK's Natural Environment Research Council.
The report is not all doom and gloom. Modelling of future scenarios suggests human societies can ease the strains being put on nature, while continuing to use them to raise living standards.
But it requires, says the MA, changes in consumption patterns, better education, new technologies and higher prices for exploiting ecosystems.
Some of the solutions go to old but as yet unfulfilled initiatives, such as the abolition of production subsidies which imbalance world trade and in agriculture are blamed for overloading land with fertilisers and pesticides as farmers chase high yields.
Newer solutions centre on putting a value on "externalities" that are currently deemed to be "free" - airlines do not pay for the carbon dioxide they put into the atmosphere; and the price of food does not reflect the cost of cleaning waterways that have been polluted by run-off of agrochemicals from the land.
In future, these areas could be constrained by markets that trade permits - as in Europe's newly established carbon emissions market.
PLANET UNDER PRESSURE
60% of world ecosystem services have been degraded
Of 24 evaluated ecosystems, 15 are being damaged
About 20% of corals were lost in just 20 years; 20% degraded
Nutrient pollution has led to eutrophication of waters and coastal dead zones
Species extinction is now 100-1,000 times above the normal background rate
Technology's role, the MA says, will be keenly felt in the field of renewable energies.
But the pace of change needs to quicken, the report warns. Angela Cropper, the co-chair of the MA assessment panel, added: "The range of current responses are not commensurate with the nature, the extent or the urgency of the situation that is at hand.
"In our scenarios, we see that with interventions that are strategic, targeted, and more fundamental in nature - we can realise some of the desired outcomes and they can have positive results for ecosystems, their services and human well-being."
The MA has cost some $20m to put together. It was funded by the Global Environment Facility, the United Nations Foundation, the David and Lucile Packard Foundation, the World Bank and others.