Netherlands Polar Data Center

The functioning of terrestrial Antarctic ecosystems is not only determined by low temperatures, but also by low nutrient availability. An important local source of nutrient input to terrestrial ecosystems is the deposition of faeces and urine by marine vertebrates such as penguins and seals. These high nutrient inputs may at a local scale have much stronger impacts than the direct effects of climate warming. However, little is known of the impact of marine vertebrates on the structure and functioning of the terrestrial food webs in deglaciated areas of the Antarctic Peninsula and on nutrient cycling in these terrestrial ecosystems. The aim of this study is to investigate how concentrations of marine vertebrates (e.g. penguin rookeries, elephant and fur seal haul outs and resting areas) affect nitrogen  dynamics and the structure and functioning of the terrestrial food web, and how this may interact with the direct effects of climate warming. At sites in the vicinity of Rothera Research Station we will determine N inputs due to vertebrate presence and study the impact on N transfer in the soil food web and on the structure and  composition of the food web. We will compare these effects with those of climate warming using our established long-term climate manipulation experiment near Rothera, and new short-term warming experiments that we will combine with N amendment experiments. This project will be one of the first to analyze in detail the linkages between marine and terrestrial Antarctic ecosystems in the context of climate change.