Orsolya Haarberg,Orsolya Haarberg / Brown Algae (Fucus dustuchus) making patterns in snow and sand. Skagsanden beach, Nordland, Norway, February. Highly commended in Plants category of the GDT 2011 competition

Juergen Freund / Aerial view of Whitehaven Beach - a seven kilometre stretch of pure white sand, Coral Sea, Pacific Ocean, August 2011

Denis-Huot / Chalk rock formations caused by sand storms, White desert in the Sahara, Egypt, February 2009

Denis-Huot / Chalk rock formations caused by sand storms, White desert in the Sahara, Egypt, February 2009

Norbert Wu / Oceanic White-tip Shark (Carcharhinus longimanus) with Pilot Fish (Naucrates ductor), Bahamas, Caribbean

Andy Rouse / Manta ray (Manta birostris) swimming on ocean floor Coral Bay, Australia

Alex Mustard / Diver blowing bubble rings, while resting on the sand, East End, Grand Cayman, Cayman Islands, British West Indies, Caribbean Sea, January 2011.

Juergen Freund / Outrigger boat in Big Lagoon, with its karst limestone cliffs, emerald waters and shallow coral reefs in the white sand. North Palawan, Philippines, May 2009.

Juergen Freund / Aerial view of coral cays and white sand bars surrounding Bugsuk Island, Farm 1 of Jewelmer pearl farm. This private island has been highly protected since the 1970's and is in pristine environmental...

Juergen Freund / Aerial view of coral cays and white sand bars surrounding Bugsuk Island, Farm 1 of Jewelmer pearl farm. This private island has been highly protected since the 1970's and is in pristine environmental...

Juergen Freund / Aerial view of a coastal island with white sand beaches, Palawan, Philippines, May 2009.

Daniel Heuclin / Rio Grande Cottonwood tree (Populus fremonti wislizenii) on a sand "pedestal" White Sands National Park. New-Mexico, USA, August 2009