Meet 75-year-old Yacouba Sawadogo from Burkina Faso in West Africa, popularly known as the 'man who stopped the desert'.
A major drought ravaged the region in the 1970s and 80s, forcing majority of the people to flee to the other parts of the country. But Sawadogo stayed on and invented a method of growing plants in pits to trap water.
After four-decades of employing 'Zai pits' technique, he has been able to create a 40-hectare oasis of thorny acacia, yellow-fruiting saba and other trees near his village.
The region that was once a desert without the shade of a single tree is now a beautiful forest.