At least half of the world should be made more nature-friendly by 2050 to ensure the wellbeing of humanity, according to the UN chief leading efforts to create a new global pact on biodiversity.

The call to strengthen the world’s life support system comes ahead of a major conference in Beijing in 2020 that many hope will be the biodiversity equivalent of the Paris climate agreement.

To reach the goal, nature reserves, ocean protected areas, restoration projects and sustainable land use regions should be steadily expanded by 10% every decade, said Cristiana Pașca Palmer, the executive secretary of the Convention on Biological Diversity.

The former Romanian environment minister sketched out the proposal amid growing scientific concern that the loss of plants, animals and pollinating insects now poses as much of a threat to human life as climate change.

“This is mega-urgent,” the UN’s top nature official told the Guardian. “We’re losing species at a rate never seen before. This is eroding the systems that sustain life on earth, including human life. It’s less visible than extreme weather but it’s killing us for sure.”

While the demise of iconic mammals such as the northern white rhinoceros tends to grab hearts and headlines, scientists say the greater threat to humanity comes from the conversion of wild habitats to farmland, the degradation of soil, overconsumption in wealthy nations and the pollution of rivers by industrial effluent, agrichemicals and plastic.

By 2020, national governments have signed up to global targets to expand protected areas to 17% of the world’s land and 10% of oceans. In addition, many countries have designated territories for sustainable development by smallholders.

But this has failed to slow the alarming decline of wild species, many of which help to produce oxygen, strengthen soil fertility or clean polluted water, or help in the production of pharmaceutical products.



Destruction of nature as dangerous as climate change, scientists warn Read more

Some prominent ecologists such as EO Wilson have argued that 50% of the planet should be set aside for wildlife, but this “half-earth” ideal is resisted by governments who are opposed to restrictions on development.



To overcome the gap between science and policy, Pașca Palmer says the 50% target should be broadened to include efforts to conserve, restore and transform land to more lower-impact use by local communities. The other half of the world – cities and bigger farms – should also be made more sustainable in terms of consumption and efficiency.



“It’s not 50% us versus 50% nature,” she said. “For developing countries the message is not that they should close off more land, but to show how more sustainable use can bring social and economic benefits.”

Global policymakers have long tried and failed to reconcile the needs of man and nature, but the UN executive said it was apparent that both needed each other.

With major biodiversity conferences due this year in Sharm El Sheikh in Egypt and then in 2020 in Beijing, Pașca Palmer said there was a lot of hype and excitement about the possibility of change. She said she would explore the possibility of accepting pledges and voluntary contributions similar to those that helped to achieve an agreement in Paris. She also called for a “nature fund” to support transitions in poorer countries with financial support from governments and corporations.

But she said time was running out and that efforts to address biodiversity – often considered an afterthought by national leaders – needed more high-level support. “We have to turn the Titanic from hitting the iceberg and we only have two years,” she said. “We need to inject a sense of urgency into political decision-making.”