The scale of action required may be daunting, but the need to act is imperative.
Time is running out to repair the damage to the planet that human beings have done, environment secretary Michael Gove is warning.
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Mr Gove will say there is a political, economic and moral need to act to tackle climate change and reverse wildlife losses in a keynote speech at Kew Gardens today (Tuesday).
And he will say that 2020 will be a crucial year for deciding the future of the planet, with international summits aimed at agreeing new deals for the oceans and for nature and increasing ambition on tackling climate change.
Alasdair Roxburgh, director of communities at Friends of the Earth, said: “It’s ironic that this speech on the urgency of the climate crisis was given surrounded by beautiful trees and wildlife, while planes from Heathrow roared overhead and plans for the third runway are supported by government.
"Alongside throwing out emissions disasters like airport expansion and fracking it’s crucial that the next government supports plans to double tree cover in the UK. If this isn’t done, getting to net-zero emissions will be little more than vague political lip service.”
The UK is bidding to host key UN climate talks next year, when countries are expected to come forward with more ambitious plans to cut greenhouse gas emission to avoid dangerous global warming.
A UN conference in China will attempt to address declines in wildlife and a new international oceans treaty is also set to be negotiated - opportunities which Mr Gove says "the world must not miss".
Domestically, he will say, the Government has ambitions for a new Environment Act that will match the success of the UK's world-leading Climate Change Act and set the path for environmental improvement for decades to come.
The environment secretary will tell the audience at the botanical gardens in London: "Time is running out to make the difference we need; to repair the damage we as a species have done to the planet we have plundered."
Nature is in retreat, with 80% of the world's forests that were standing 8,000 years ago cleared, damaged or fragmented, and species becoming extinct at a rate estimated to be 1,000 to 10,000 times higher than they would naturally.
Climate change is causing sea level rise and even if action is taken now to slow carbon dioxide pollution, the climate will keep heating up for decades to come, he will warn.
"The scale of action required may be daunting, but the need to act is imperative," he will say.
"There is a political need to act - because we cannot leave this planet to the next generation more polluted, more dangerous, denuded of its natural riches and increasingly inhospitable to all life.
"There is an economic need to act - because unless we restore our natural capital then we will have depleted soils incapable of yielding harvests or sustaining livestock, we will have oceans with more plastic than fish, we will have dried up or contaminated water sources and we will have severe weather events endangering lives and livelihoods.
"And there is a moral need to act - because, as Margaret Thatcher reminded us, we do not have a freehold on this planet, it is not ours to dispose of as we wish, we are partners in the great chain of evolution with the rest of nature and endowed as we are with reason we therefore have the responsibility to steward and protect," he will say.
Emily Beament is the Press Association environment correspondent.