Mali villagers fight back against Sahara

"Dig, dig," he boomed cheerfully at a crowd of several hundred villagers standing in the scorching sun in a dried-out river bed, some four hours' drive west of Timbuktu.

The narrow channel, overshadowed by a line of imposing yellow sand dunes, used to flow into Lake Faguibine, helping to carrying an annual flood surge from the mighty Niger River into an ecosystem that directly supported some 200,000 people, and produced food for Mali, Burkina Faso and Mauritania.

It was the region's most fertile farmland.

But over the past three decades, a combination of droughts, desertification and local mismanagement have turned Lake Faguibine into a shrivelled, dusty plain.

Agricultural production has collapsed, conflict between farmers and cattle-herders has intensified and tens of thousands of people have abandoned the region.

The lake has been dying.

"We can't just sit back and wait for the desert to conquer us," said the colonel, surveying the digging work like a front-line general. "We must fight back."

And so, across the vast, dry scrubland south of Lake Faguibine, channels are being cleared, by hand and sometimes by bulldozer, dunes stabilised with saplings and villagers encouraged to take part.

Now, after four years of work paid for by the Malian government, there are some encouraging signs of progress.

Col Ascofare smiled as he watched a trickle of water move across the dry sand towards the lake, gently leading the way for the flood waters building up behind it.

"Inexorably, perhaps, the climate will deteriorate," said the colonel.

"But we have proved we can delay the advance of the desert. In 2006, only 100 hectares of land around the lake was farmed. This year it will be more than 20,000 hectares."

Kouna Mohammed sat in a group, cheerfully sifting sorghum, as her sons brought in this year's crop from the green fields around them.

Like many families, they had abandoned the lake years ago. Several relatives had died because of the drought. But the past two years have seen a dramatic improvement.

"Without water, there is no world," said a neighbour, Medel Al Houseini.

Recently, the United Nations Environment Programme (Unep) agreed to help the Malian government, with a $15m (£9.2m) project for the Lake Faguibine system.

"That's peanuts in relation to the benefits that will accrue," said Unep's spokesman, Nick Nuttal. "What we're trying to demonstrate [ahead of the Copenhagen climate change summit] is that large-scale renovations of ecological infrastructure are possible."

Unep argues that countries like Mali, which are considered to be on the front lines of climate change, need help now to enable them to cope with much tougher conditions expected in the years ahead.

Leading Unep's work on the ground, Birguy Diallo showed a group of villagers how to stabilise the dunes with twigs and saplings.

"We're here to win," she said. "The villagers are already seeing they can gain from this.

"They're working for their own benefit, not for outsiders. They were born here, and live here. They are supposed to stay here."

But the lake's future is far from certain.

Mali is poor, and its government riddled with corruption.

Before Col Ascofare took the lead, similar projects appear to have achieved nothing.

The colonel is clearly frustrated by the slow pace of change.

With outside help and heavy equipment, he estimates that he could have achieved in six months what has now taken four years.

"Without foreign help, it's impossible," he said flatly. "The costs are enormous. We need lots of equipment and lots of technical education to fight against all this sand you see around us.

"We expect much from Copenhagen and the international community."