Delegates from across the world have gathered in the Japanese city of Nagoya?Monday for a United Nations conference to discuss a new strategy to halt the alarming loss of the Earth's biodiversity, driven largely by human activity, a trend experts warn threatens the planet's capacity to sustain human well-being.

"Here there is an opportunity to shape the landscape and the trajectory of humanity's response to the loss of its natural and nature-based assets in profound and transformational ways," Achim Steiner, the Executive Director of the UN Environment Programme (UNEP), told the opening session of the 12-day Conference of Parties to the UN Convention on Biodiversity (CBD).

"Here and together we can begin to put in place the kinds of far sighted policy-responses and smart mechanisms that have been incubating for years in many countries and communities," he added.

During the event, more than 15,000 participants – the highest number ever recorded for such a meeting – representing the 193 Parties and their partners are expected to wrap up negotiations on a new strategic plan on biodiversity for the 2011-2020 period.

That plan will be submitted to the high-level segment of the conference, which will begin on 27 October and will be attended by several world leaders and more than 100 environment ministers.

Ahmed Djoghlaf, the Executive Secretary of CBD, said that species extinction rates are now as high as a thousand times the natural rate, and that the world is nearing a "tipping point" where there could be irreversible loss.

"Let's have the courage to look in the eyes of children and admit that we have failed," he said.

Mr. Steiner highlighted the findings of the Millennium Ecosystem Assessment of 2005 which concluded that 60 per cent of the services provided by the world's ecosystems that support human well-being are now either degraded or are nearing degradation.

It also found that changes in biodiversity as a result of human activities have been more rapid in the past 50 years than at any other time in human history.

The UNEP chief said that the report "underlined that rather than exercising the brake, the world continues to choose the accelerator.

"This is hurtling us all on a collision course towards an extremely sobering destiny. The issue in front of this meeting is whether human beings have the collective intelligence, wisdom and common humanity to read the writing on the wall."

Mr. Steiner underlined the need for humanity to recognize that the stability and human well-being in the 21st century will rest on the fate of all life on Earth.

"Science tells us that we are currently going through the sixth wave of extinctions," he said, questioning how long until human beings are included on the list of threatened species issued by the International Union for the Conservation of Nature (IUCN).

"If that is what science is telling us, what will this meeting tell the world it is doing about it?

The plants and animals, fungi and micro-organisms that produce and clean our air, generate drinking water, hydro-power and irrigation; provide food, shelter and medicines and also bring to many joy and a spiritual dimension to our daily lives need a big helping hand from this 10th Meeting of the Conference of the Parties – if not for their sakes, but for ours."

In a related development, UNEP announced today that a mapping exercise to identify where countries' carbon stocks overlap with areas that are rich in wildlife and important for local peoples' livelihoods is under way in Asia, Africa and Latin America.

The project aims to support international efforts to conserve forests in order to combat climate change, in a way that delivers other benefits, including conservation of economically-important ecosystems linked with water, fertile soils and other crucial services.

Under the UN Framework Convention on Climate Change (UNFCCC), governments are negotiating a mechanism to provide payments for the so-called UN REDD+ scheme, which seeks to create incentives to reverse the trend of deforestation and conserve forests' carbon stocks.

According to UNEP, nearly 20 per cent of greenhouse gas emissions result from changing the way land is used, mainly through deforestation.