Development of an automatic sampler for extreme polar environments: first in situ application in Svalbard Islands.

Increased attention has recently been addressed to Arctic ecosystems due to the well-known impact of global warming on the northern polar region. Advanced technologies for marine monitoring are needed to monitor environmental changes, especially those related to ice melting. In the framework of the ARCA project aimed at studying the hydrological cycle and its consequences on the climate in the boreal hemisphere, a first prototype of automatic equipment was specifically designed to perform discrete sampling of waters in the area close to the Kronebreen glacier, in the Svalbard Archipelago. This study reports the results of the first in situ application of this device related to the study of heterotrophic bacterial distribution and functional metabolism. Along a transect from the glacier to offshore, a high culturable heterotrophic bacterial abundance was observed close to the glacier. Significant spatial differences were recorded in the values of leucine aminopeptidase and beta glucosidase enzymatic activities, with high microbial glycolytic activity close to the glacier. The patterns of extracellular enzymatic profiles of the bacterial isolates showed that lipids, proteins and organic phosphates play a major role in bacterial metabolism in this area of the Arctic Ocean.