Along a riverbank scarred by logging, Joseph Mwandenge Mangi points out a solitary mangrove tree, a species once abundant in the forest where the mighty Sabaki River meets the sea. “This is the last one. There are no more left,” said the 42-year-old Kenyan, who grew up on the estuary and possesses a seemingly encyclopedic knowledge of its flora and fauna. The surviving tree is a sombre reminder for local communities working to restore this critical ecosystem to health, and make amends for the plunder of the past. For generations villagers living near the Sabaki estuary had relied on its natura…