The RSPB’s former director of conservation, Mark Avery, is illuminating the road to the Rio+20 Earth Summit with 20 guest blogs.

Here he is on the subject of sustainable development – defining what the mantra of ‘SD’ actually is, has been harder than you would think.  After the first Earth Summit 20 years ago we developed a partial definition that to be sustainable, development should lead to no net loss of biodiversity.  Doesn’t exactly trip of the tongue – but in essence development that diminishes our stock of life on earth is fundamentally unsustainable. And this blog has covered a lot of proposals that fail that test.

But in reality we need to go further and restore a countryside rich in wildlife, not just protect the fragments that remain. A few months ago, the coalition Government published the National Planning Policy Framework (The NPPF) – which redefined the duty of sustainable development in England. 

We were delighted that this important document included the following words: ‘Pursuing sustainable development involves seeking positive improvements in the quality of the built, natural and historic environment, as well as in people’s quality of life, including ... moving from a net loss of biodiversity to achieving net gains for nature’. Here, here.

The announcement of over £7m for the establishment of 12 Nature Improvement Areas in England was another welcome announcement earlier in the year

The Olympic opening ceremony will recreate a speck of our countryside for three hours - a good idea? Well it might be if the penny finally drops about how hard-wired our emotions are to our landscapes and countryside (and the green urban bits too).

When I saw the plans for the opening ceremony unveiled I couldn’t help recalling how last year we launched plans to transform Trafalgar Square ... admittedly it was on 1 April, but with an Olympian £27m, who knows?

Our Trafalgar vision - of April fools day 2011

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