WASHINGTON, D.C. — Humans have pushed about 1 million varieties of plants and animals to the brink of extinction, according to a new United Nations Report that arrives as congressional Republicans and the Trump administration try to diminish endangered species protections in the United States.

Many of the species identified in the report could be extinct within decades, it says, amid a “mass extinction event” caused by humans putting more flora and fauna on the edge of eradication than ever before in their history. By transforming land and waterways, exploiting organisms, polluting, shifting species’ habitats and fueling climate change, humanity has eroded nature dramatically since the Industrial Revolution, according to the authors.

The report, written by 145 researchers from 50 countries in the last three years, is the most thorough piece of research to date on the collapse of biodiversity on Earth, which is unfolding at an “unprecedented rate,” and the repercussions of human actions.

“Biodiversity and nature’s contributions to people are our common heritage and humanity’s most important life-supporting ‘safety net,’” Sandra Diaz, a co-chair of the report, said in a statement. “But our safety net is stretched almost to breaking point.”

While heat-trapping emissions climb and ecosystems are threatened by elimination, President Donald Trump’s administration wants to rewrite the Endangered Species Act, the 1970s law considered the gold standard for species protection globally, and Congress has yet to take up any robust legislation to address biodiversity.

Supporters of the changes argue that current rules usurp the power of states to devise their own strategies to protect their plant and animal life, and inhibit economic development, especially in western states.

Trump’s former interior secretary, Ryan Zinke, proposed three rules last year to significantly weaken the Endangered Species Act. One proposal would water down the protection for species “threatened” under the law, while another would not consider incremental harms to habitat unless they directly hurt species.

Those regulations are expected to be finalized within weeks.

“Even in the face of an extinction crisis that could burn through a million species, Trump seems intent on pouring more gasoline on the fire,” Noah Greenwald, endangered species program director at the Center for Biological Diversity, which has sued the Trump administration more than 100 times, said in a statement about the U.N. report.

“His administration is kneecapping the Endangered Species Act and giving polluters free rein at the worst possible time, when our planet’s wildlife is already headed for disaster,” he said.

Separately, the administration is working to roll back protection for species in the U.S. to the benefit of oil-and-gas drilling and exploration where vulnerable animals live.

Under Interior Secretary David Bernhardt, the federal government, through the U.S Fish and Wildlife Service, in March moved to remove the grey wolf from protections under the Endangered Species Act. Also in March, the Bureau of Land Management shrank protection for the sage grouse in seven western states, following requests from Republican governors and oil companies to do so. And the administration has moved forward with plans to drill in the Arctic Ocean, off Alaska’s northern coast, where caribou migrate to give birth.

In an emailed statement, Jacob Malcom, director of the Center for Conservation Innovation at the Defenders of Wildlife, said broad policy decisions are particularly threatening.

“The most damaging actions for biodiversity from the Trump administration are not necessarily species-specific,” Malcom said. “They are big national policy changes, such as long-lasting damage to the Endangered Species Act programs through budgetary cuts, as well their revisions of the ESA regulations and roll backs of protections on federal lands and waters.”

With Earth’s human population expected to hit 9 billion in 2050, dramatic and aggressive steps are needed to stabilize species populations, scientists say.

Since 1900, native species in “most major” land habitats have decreased in population by at least 20%. More than 40% of amphibians, more than 33 percent of “reef forming corals,” and more than one-third of marine mammals are at risk of extinction.

Ecosystems, species, wild populations, local varieties and breeds of domesticated plants and animals are shrinking, deteriorating or vanishing,” Josef Settele, another co-chair of the study, said. “The essential, interconnected web of life on Earth is getting smaller and increasingly frayed.”

In an interview, Greenwald said the U.S. government is making species conservation harder.

“They make it harder for species to gain protection,” Greenwald said. “They really just go against the science.”

Officials at FWS announced last week the agency was removing the American burying beetle from Endangered Species Act protections. The beetle, like other elements of nature, provides a service for society that can go unnoticed: It cleans up carrion by burying carcasses in which it lays eggs that will hatch into larvae that feed off the body.

In the U.N. study, the authors underscore how plants and animals pollinate crops, purify air and water, create natural medicines and food stocks, and gird against flooding and natural disasters.

As Greenwald put it, they recognize the value of what ecosystems naturally do and protect.

“A clean river has value for all of us, but you can’t sell it,” he said.