Representatives from more than a-hundred and fifty countries are meeting in the Senegalese capital, Dakar, to discuss how to combat the spread of deserts.

The conference -- said to be the biggest of its kind ever held in Africa -- is also being attended by about five-hundred environmental organizations.

Over the next ten days, delegates will try to reach a consensus on how to tackle the problem.

Many environmentalists blame desertification on the destruction of forests for short-term gain.The conference organisers estimate that the spread of barren land could eventually threaten a billion people world-wide.