Richard Du Toit / Aerial photo of hillside gully erosion, KwaZulu Natal, South Africa, June 2010

Michel Roggo / Underwater landscape in Verzasca River, Ticino, Switzerland, September

Michel Roggo / Underwater landscape in Verzasca River, Ticino, Switzerland, September

Inaki Relanzon / Eroded slopes of Landmannalaugar highlands, central Iceland

Inaki Relanzon / Stream meandering though barren landscapes of Landmannalaugar highlands, central Iceland

Inaki Relanzon / Barren landscape of Landmannalaugar highlands, central Iceland

Inaki Relanzon / Barren landscape of Landmannalaugar highlands, central Iceland

George Chan / The stripes and gullies of the Five-Coloured Mountains in Xinjiang Province, North-west China. September 2006

Fabio Liverani / Man walking through the Las Penitas rural park of Betancuria, Fuerteventura, Canary Isles, Spain, September 2007

Niall Benvie / Tornuvik, a township at the base of a cliff Streymoy, Faroe Islands, Denmark. June 2006

Chris Gomersall / Streams of meltwater on mountainside. Eyjafjördur, Iceland. July 2006

Marc Robillard / Patterns in the sand when the tide has retreated on the beach at Saint-Malo, Brittany, France.

Marc Robillard / Abstract patterns in the sand when the tide has retreated on a beach in St Malo, Brittany, France.

Jose B. Ruiz / Sonsaz Reserve, Tamajon, Guadalajara, Spain