Decline in microbial genetic richness in the western Arctic Ocean

Researchers analyzed archival samples of bacteria and archaea populations taken from the Beaufort Sea, bordering northwest Canada and Alaska. The samples were collected between 2004 and 2012, a period that included two years -- 2007 and 2012 -- in which the sea ice coverage was historically low. The researchers looked at samples taken from three levels of water: the summer mixed layer, the upper Arctic water below it and the Pacific-origin water at the deepest level. The study examined the microbes' genetic composition using bioinformatics and statistical analysis across the nine-year time span. Using this data, the researchers were able to see how changing environmental conditions were influencing the organisms' structure and function.