Expect not merely a trend but a whole new wave: eco-art will be huge this summer. Once ecology was the preserve of the arty-farty-crafty green set, but now it is moving on to a bigger, bolder canvas.

From the Barbican to the Tate and café-galleries in the back lanes of Brighton, there is a backlash against Hirstian bling and a race to score political points. Preserving sharks in formaldehyde is over; the days of preserving sharks in the ocean are here.

The Barbican is wading into the debate on our shifting climate and landscape with a mega-exhibition, Radical Nature — Art and Architecture for a Changing Planet, opening next month.

Railing against environmental degradation will be architects such as the Ant Farm collective and Richard Buckminster Fuller, and artists such as the tree-planting-obsessive Joseph Beuys.

The exhibition, with 50 live events, is the first, claims the Barbican, “to bring together key figures across different generations who have created Utopian works and inspiring solutions for our ever-changing planet”.

Meanwhile Heaven and Earth, an exhibition of the 80 works of Richard Long, is at Tate Britain from June 3. This visionary landscape artist uses the landscape as a medium. He is famous for his extended, solitary walks through remote areas of Britain, or the wilds of Mongolia, when he marks the ground or adjusts natural features for photographs, sculptures and the sure-to-be-popular “large-scale mud wall”.

Of course, Land Art has been around for ever, and making sculpture with “found” objects is every art student’s cheap-as-chips salvation. Rubbish and excrement have never waned in popularity as useful tools, from Piero Manzoni’s fake tinned turds to Chris Ofili’s elephant dung and Mark Quinn’s self-made daubs. But the new eco-art movement is not merely about the medium, but the message too.

The picture becomes clearer if we visit two eccentric eco-artists in Brighton whose work exemplifies the combative mood around the country. Their “Dirty Beach” exhibition does what it says on the tin. The environmental artist Lou McCurdy spent months gathering the detritus on Brighton beach, from plastic Toilet Duck bottles to orange nylon rope and the lost pink arms of Action Men.

Living on the coast, McCurdy became obsessed with the damage done by everlasting plastic to the oceans. She read about the trash vortex, a continent twice the size of Texas, made of discarded plastic shreds, floating endlessly in the North Pacific subtropical gyre, and she contacted the renowned marine biologist Richard Thompson, at Plymouth University.

Thompson discovered that the sand on all our beaches contains gazillions of tiny grains of plastic, made small by the mechanical grinding of waves. The plastic attracts toxins and enters the food chain: “When they get as small as powder, even zooplankton will swallow them,” he says.

Those tiny plastic grains are known oddly as “mermaids’ tears” to scientists, and it was at this point that a second Brighton artist entered the campaign: Chloe Hanks, a graphic designer. By scraping away algae on rocks on the beach, Hanks was able to create “mermaids’ tears” graffiti.

While McCurdy’s materials would last for ever, “like a throwaway plastic disposable lighter”, Hanks’s idea was to paint Banksy-style slogans on public buildings and even parked vans in Brighton. But all her “paint” would be biodegradable — “beetroot juice, moss, chalk, milk — I’ve tried the lot”, she says.

Thus Hanks’s works of art never lasted more than a few days, except in the photographs in the Dirty Beach shown in the gallery above Café Delice (continuing now after the Brighton Festival). When it snowed last winter, Hanks rushed down to the beach with stencils and flasks of boiling water.

She strategically melted the snow until the message appeared in a cool typeface: “Under This Clean White Exterior, I’m a Right Dirty Beach.” The great work of protest endured for an afternoon, but it reached well beyond the middle-class gallery-going audience.

As the Dirty Beach project took on momentum, Hanks and McCurdy got fired up and last week they went to lobby Parliament with members of the Marine Conservation Society. “We both wore our Dirty Beach T-shirts, but we weren’t allowed in until we turned them inside out,” she laughs. “Political slogan, you know.”

At a photocall, the artists turned their T-shirts the right way round, revealing bras in the halls of Westminster as MPs fiddled their expenses in the background and the planet burnt.

Now that the scientists, and to some extent film-makers, have done the spade work on our ongoing destruction of the Earth, it’s the turn of artists to bring the issues upfront and in your face. There are 2,195 pieces of rubbish per kilometre on the average British beach, about half of which is dumped by the public. No artist can handle this alone.

We shall all be beached together unless we join the revolt. Not since Blue Peter brought us 101 uses of the yoghurt pot has trash been so fashionable.

Kate.muir@thetimes.co.uk

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