Ricerc@Sapienza

In the Ross Sea, biodiversity organisation is strongly influenced by sea-ice cover, which is characterised by marked spatio-temporal variations. Expected changes in seasonal sea-ice dynamics will be reflected in food web architecture, providing a unique opportunity to study effects of climate change. Based on individual stable isotope analyses and the high taxonomic resolution of sampled specimens, we described benthic food webs in contrasting conditions of seasonal sea-ice persistence (early vs. late sea-ice break up) in medium-depth waters in Terra Nova Bay (Ross Sea).

Stable isotope analysis has become known as an important approach in ecological science but also in Geology, Biology, Climate, Organic chemistry, Botany and Zoology. The stable isotopes of Nitrogen (δ15N) and Carbon (δ13C) enable powerful tools for evaluating the origins of Nitrogen pollution in water systems and, associated to Bayesian Mixing Models, are the elective method to assess the trophic positions of the different taxa in food webs. Nowadays, stable isotope analysis is utilized to address questions about human diets around the world.

Non-native freshwater fish species can have adverse ecological impacts on native populations. However, the mechanisms determining the success or otherwise of their invasion and their role in invaded communities remain largely unknown. This is particularly true for the Mediterranean region, where endemic species characterised by restricted natural ranges may be at high risk of extinction. The largemouth bass (Micropterus salmoides) is native to North America but is invasive in the Italian Peninsula. The aim of this study was to explore the trophic position of M.