Redd in Africa: 'how we can earn money from air by harvesting carbon'

Rukinga ranch in southern Kenya prides itself on the immense herds of elephants, giraffe, lions and and wild dogs that have made a home among its 80,000 acres of acacia trees in the decade since cattle were banned. But the wildlife sanctuary's guards who risk their lives to defend the animals from poachers now face an even greater danger.

Rukinga is on the frontline of global deforestation: every month, dozens of large gangs of commercial charcoal-makers are caught cutting down trees and building crude fire pits to make cooking fuel for the port city of Mombasa 100 miles away. No one knows exactly how many thousands of tonnes of trees are lost a year, but at estimated present rates the reserve could be like much of the land between it and the coast – semi-desert, treeless and barren of animals – within 20 years.

This could change this week if countries agree to back a revolutionary UN plan to preserve the world's forests by allowing owners to trade the carbon stored in endangered forests on condition the trees are not felled. The plan aims to slash the 20% of all greenhouse gas emissions that come from deforestation and is one of the few aspects of a global deal to fight climate change that looks on track to be settled, with key talks taking place this week in Bangkok.