Alejandro Chaskielberg has won the coveted award for his High Tide project, which BJP featured in October 2010. The work offers an "insightful look into the lives of a community of islanders who live on the Parana River Delta." For High Tide, Chaskielberg lived with the islanders for two years, "immersing himself in their daily life in order to document the way they live and work."

Shooting at nighttime close to water, Chaskielberg says he intends to work "on the border of reality, creating fictional scenarios with real people and situations, trying to push the limits of documentary photography, using technical processes to transform the natural perception of light, colours and spaces".

His winning photos were selected from among more than 105,000 images that were submitted from 162 different countries. In addition to winning $25,000, the Argentinian photographer has also received a Sony digital SLR camera, and has become part of the World Photographic Academy alongside previous winners - David Zimmerman, Vanessa Winship and Tommaso Ausili.

"The judging process is never straightforward when comparisons are made between imagery of so many different types on such a wide range of subjects," says Francis Hodgson, a photo critic and chairman of the 2011 Honorary Judging Committee. "Yet this year's panel of judges found no great difficulty in agreeing to honour the powerful work of Alejandro Chaskielberg's series High Tide. These carefully directed pictures tell solid truths - about toil and communality and marginal economic survival - in a splendidly allusive way."

Born in 1977, Chaskielberg began shooting for local newspapers at the age of 18, and after studying for a degree at the National Film Institute in Argentina, then started to make television documentaries. He began showing his new stills work four years ago, immediately collecting one of the most prestigious prizes for young Argentinian artists, and two years later gaining more worldwide attention after winning recognition from the National Geographic Society. He has since won numerous awards, including the $15,000 Emerging Photographer Grant from Burn magazine, run by Magnum photographer David Alan Harvey.

The Hunter, part of the High Tide series © Alejandro Chaskielberg, courtesy of Sony World Photography Awards 2011.

Last year, Martin Parr selected High Tide to be shown at the Brighton Photo Biennial. "Chaskielberg documents the communities that live around the Paraná River Delta near Buenos Aires," said Parr in an interview last year. "They inhabit rather delicate wooden structures and travel around in small boats. Setting up his photographs, to be taken at full moon on a 5×4 camera (with a small lick of flash to complement the ambient moon light), he invests substantial time rehearsing the shot with his selected subjects."

In October 2010, Chaskielberg explained to BJP how his images came about:

Chaskielberg's will go on show, from 29 April, at Somerset House, alongside Sony World Photography Awards' other nominated and category winners.

For more information, visit www.worldphoto.org and www.chaskielberg.com.