The arid New Mexico desert is home to a cluster of unusual buildings called 'earthships' – environmentally sustainable, self-sufficient homes made using recycled and natural materials. They represent the life's work of Mike Reynolds, a radical architect who is passionate about proving that truly green building design can work. Each of his earthships heat and cool themselves, harvest their own water and use plants to treat their sewage, with soil-packed discarded tyres making up the main building material. The ideal earthship is entirely carbon neutral.

The basic versions of these earthquake-resistant buildings can cost as little as $4,000, and can be built quickly using local waste materials, making them ideal for post-disaster areas. More than 1,000 earthships have been built around the world, from Australia to Haiti to Southern England.

Russell Beard visits the original earthship community in New Mexico, to meet the big thinker behind these ground-breaking buildings.

The almost complete disappearance of the Aral Sea in Central Asia, once the world's fourth largest lake, is one of mankind's greatest environmental blunders. But the North Aral is now being revived, thanks to measures such as improved water management, fish reintroduction programmes and the 13-kilometre Kok-Aral dam.

The size of the North Aral Sea has increased by more than 50 per cent compared to its lowest point. Salinity has decreased, several fish species have returned and the fish catch has increased 10-12 times. Robin Forestier-Walker ventures into the vast Aral region to find out how the project is working.

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