Graham Eaton / Underwater view of a mountain lake with frozen surface, Llyn Idwal, Snowdonia NP, Gwynedd, Wales, UK, December

Graham Eaton / Split level shot of Llyn Idwal and Cwm Idwal, showing freshwater habitat with Green lacustrine algae (Chlorophyceae sp.), Snowdonia NP, Gwynedd, Wales, UK, August

Roberto Rinaldi / Yellow fan coral / Seafan (Paramuricea clavata) amongst mass of invasive algae (Caulerpa taxifolia) with Rainbow wrasse fish (Coris julis), Strait of Messina, Southern Italy

Willem Kolvoort / Aquatic plants and algae in river, River Black Drim, Albania, Eastern Europe, May 2009

Willem Kolvoort / Underwater freshwater springs in the River Black Drim, Albania, Eastern Europe, May 2009

Alex Mustard / 2020VISION / Tufts of seaweed growing on a shallow seabed, Island of Coll, Inner Hebrides, Scotland, UK, June

Alex Mustard / 2020VISION / Meadow of seaweeds in a shallow channel between islands in the Cairns Of Coll, Island of Coll, Inner Hebrides, Scotland, UK, July

Alex Mustard / 2020VISION / View up through tidepool of 2020Vision young photographer, Bertie Gregory, Falmouth, Cornwall, UK, July 2011. Model released. Did you know? Life isnt easy in a rock pool! Animals here must deal with c...

Bernard Castelein / Common Eider (Somateria mollissima) chick on beach, Helgoland, Germany, May

Graham Eaton / Ice on lake surface seen from below. Llyn Idwal, Snowdonia, Wales, December 2010.

Graham Eaton / Under the ice scene of freshwater frozen lake. Llyn Dinas, Snowdonia, Wales, December 2010.

Graham Eaton / Split level image of Cwm Idwal and Llyn Idwal showing lake and mountain habitat and lacustrine algae, Snowdonia NP, North Wales, UK, January 2010. Winner of the Living Landscape: Connectivity categor...