Most people know rainforests are vital in the fight against climate change, but now scientists say wetlands could be even more important.

Saltmarshes, mangrove swamps and wetlands can absorb carbon "four times faster than trees", according to the charity the Wildfowl and Wetlands Trust (WWT).

Celebrating 80 years since WWT's first wetland bird reserve was founded at Slimbridge, in Gloucestershire, the charity's leaders have called for one million hectares of wetlands to be restored across the world.