Vanesa Salinas, Tomas Ignacio Marina, Georgina Cordone, FERNANDO MOMO

Interactions between organisms are very diverse and attend to multiple biological demands, hence understanding ecological communities requires considering different types of species interactions beyond predation. In this work, we assemble for the first time the non-trophic networks of an Antarctic ecosystem. We report mutualistic (+/+), competitive (-/-), commensalistic (+/0) and amensalistic (-/0) interactions between species of Potter Cove marine community (South Shetland Is., Antarctica). Based on network approach we present a full description of each type of interaction and analyze its distribution according to different species-level properties. Also, we construct a multiple interactions network including trophic and non-trophic interactions and study networks-level properties. We found more than double non-trophic interactions than trophic ones mostly corresponding to competitive interactions involving mid-trophic level species. Low-trophic level species were mainly involved in mutualistic and amensalistic interactions. We observed that interactions networks display differences of its structural properties. Finally, we study the importance of adding non-trophic interactions to gain insight into the function of the whole community. We show that including a description of species interactions in ecological networks analysis provides a better understanding of ecosystems as a whole which could be crucial to comprehend and predict ecosystems responses to environmental disturbances.