18:30 23 April 02 NewScientist.com news service Colossal icebergs that fractured away from an Antarctic ice shelf in 2000 have dramatically reduced the growth of sea phytoplankton in a region of the Ross Sea. Scientists fear this could disrupt the food chain is this biologically rich area. Satellite data shows the volume of phytoplankton in the southwestern Ross Sea fell by about 40 per cent between March 2000, when the icebergs broke away from the Ross Ice Shelf, and December 2001. A single iceberg measuring 10,000 square kilometers first sliced away from the shelf before breaking into smaller icebergs. The icebergs became grounded...