Juergen Freund / Siltation underwater from a river after the rains with diver, Papua New Guinea

David Woodfall / Villagers living in former river bed now dry due to siltation, complex effects of climate change, Ganges delta, Bangladesh, November 2008

Suzi Eszterhas / Polluted murky water of main river meeting clean black water of Sekonyer River, Tanjung Puting National Park, Indonesia

Suzi Eszterhas / Polluted murky water of main river meeting clean black water of Sekonyer River, Tanjung Puting National Park, Indonesia

Matthias Breiter / Cline River showing heavy siltation and braiding, Jasper National Park, Alberta, Canada

Christian Ziegler / River with sediments caused by erosion due to deforestation for oil palm plantations, Niah National Park, Sarawak, Malaysia

Christian Ziegler / River silted by erosion due to deforestation for oil palm plantations, Niah National Park, Sarawak, Malaysia

Juergen Freund / Aerial view of estuarine channel with mangroves at the mouth and some barren patches, and siltation at the mouth of the channel, Palawan, Philippines, April 2010.

Juergen Freund / Aerial view of the town of Taytay where massive road developments and landslides have carved out their image in the landscape, and caused deforestation and siltation, Palawan, Philippines, April 2010.

Juergen Freund / Aerial view of agricultural landscape of Palawan which has resulted in deforestation of the lowland forest adding to siltation along the coast, Palawan, Philippines, April 2010.

Juergen Freund / Aerial view of slash and burn areas on islands causing run-off of soil and siltation of the coastal reefs, Palawan, Philippines, May 2009.

Juergen Freund / Aerial view of slash and burn area on island causing run-off of soil into the coastal reefs and siltation, Philippines, May 2009.

Juergen Freund / Aerial view of agricultural landscape of Palawan which has resulted in deforestation of the lowland forest adding to siltation along the coast, Palawan, Philippines, April 2010.

Juergen Freund / Aerial view of Southern Palawan coast showing strong heavy siltation, the result of deforestation, April 2010.

Juergen Freund / Aerial view of agricultural landscape of Palawan which has resulted in deforestation of the lowland forest adding to siltation along the coast, Palawan, Philippines, April 2010.

Juergen Freund / Aerial view of agricultural landscape of Palawan which has resulted in deforestation of the lowland forest adding to siltation along the coast, Palawan, Philippines, April 2010.

Fraser Gunn / Hooker River and Tasman River flowing into Lake Pukaki, Mackenzie Country, New Zealand

Murray Cooper / Tiputini River aerial showing silted water, Yasuni National Park, Ecuador

David Woodfall / View of river showing how reduced river flow leads to siltation and waterlogging, Ganges delta, Bangladesh, November 2008

David Woodfall / View of river showing how reduced river flow leads to siltation and waterlogging, Ganges delta, Bangladesh, November 2008

David Woodfall / Aerial view of river showing how reduced river flow leads to siltation and waterlogging, Ganges delta, Bangladesh, November 2008

David Woodfall / Aerial view of river showing how reduced river flow leads to siltation causing tree death and waterlogging, Ganges delta, Bangladesh, November 2008

David Woodfall / Aerial view of waterlogged garden, waterlogging caused by river siltation in the Ganges delta, Bangladesh, November 2008

David Woodfall / Woman hanging out washing in waterlogged garden, waterlogging caused by siltation of rivers, Bangladesh, November 2008

David Woodfall / Flooding caused by the effect of waterlogging resulting from the siltation of rivers, Ganges delta Bangladesh, November 2008

David Woodfall / Siltation caused by reduced river flow and leading to waterlogged land and flooding, Ganges delta, Bangladesh, November 2008

Theo Allofs / Braided river delta showing floodplain, channel bars and channels, Katmai, Alaska

Theo Allofs / Braided river delta showing floodplain, channel bars and channels, Katmai, Alaska

Konrad Wothe / Betsiboka River laden with silt from erosion caused by deforestation, Madagascar

Juergen Freund / Corals on a reef off Dunk Island, Australia, suffering from siltation. Indo-pacific

Albert Lleal / Spirke (Pinus uncinata) forest drained of sediments following heavy rains, Pyrenees, France

Tim Fitzharris / Silted river flowering through Glen Canyon National Recreation Area, Utah

Juergen Freund / Aerial view of siltation at a rivermouth close to Bundaberg, Queensland, Australia

Pete Oxford / Napo River heavily silted and Yasuni National Park, Amazon, Ecuador

Gerry Ellis / Alluvial run-off from up stream erosion, lowland tropical rainforest on the Gulf Coast, Papua New Guinea