The 2009 Prix Pictet environmental photography prize has been awarded to Nadav Kander for his collection Yangtze, The Long River Series, 2006-07. All photos: Nadav Kander, courtesy of Flowers Gallery/Prix Pictet 2009
The images from this series depict the rapidly changing landscape and communities of China's Yangtze River.
The Yangtze is the main artery that flows 6500km across China, from its furthest westerly point in Qinghai Province to Shanghai in the east.
Using the river as a metaphor for constant change, Mr Kander photographed the landscape and people along its banks from mouth to source.
More people live along these banks than live in the entire US.
The photographer said his images depicted "the sheer force" of development along the river.
He said he felt like "a complete outsider" during his journey, and explained this by “stepping back” and showing humans dwarfed by their surroundings.
The landscape is changing daily, both economically and physically, Mr Kander said. "These are photographs that can never be taken again."
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