Livingston Island, located at the tip of the Antarctic Peninsula (Fig. 1),is characterised by an oceanic polar climate with temperatures above0°C for 4 months per year and a mean annual precipitation between 400and 500 mm. Under these conditions a soil formation can be observedand lichens, mosses and some higher plants are able to grow in thisenvironment. Since cultivation-independent methods have become animportant tool to investigate environmental microbes, it is possible toanalyze complex microbial networks in the face of diversity, abundance,ecology and their reaction on climate change. Here, we investigated thebacterial community structure of different soil and sediment habitatslocated on Livingston Island by polymerase chain reaction (PCR) usinga specific primer set followed by denaturing gradient gelelectrophoresis (DGGE) to get a first insight in the diversity of bacteriaexisting under these conditions. The aim of these studies is to identifythe main microbial players in nutrient turnover and to get an idea of thefunctioning of microbes within periglacial ecosystems.