marsh

The process of salt collection in San Francisco Bay was industrialised in the 1800s but now the bay's salt ponds are part of a major restoration project, bringing back tidal marshes and wildlife.

It includes woodland, heathland, marshes and seven lakes, including Powell's Pool, where the teenager's body was discovered.

They say restoring part of the lake and its marshes would revive vital habitat for wildlife, bringing the area a new park where people could fish, watch migrating birds and walk along the water’s edge.

The Florida Everglades are a unique environmental region comprising marshes, prairies, forests, mangroves and estuaries.

Analysing gases in the air flowing around the marsh - over the course of a year - revealed how plants there "breathe in" more carbon dioxide in the summer than they release in winter.