Understanding internal and external effects on the composition of marine ecosystems

Trabajo presentado en el IFISC Poster Party (online).-- The IFISC Poster Party is an annual activity where PhD students and postdoctoral researchers of IFISC present their research in a poster format.-- Biocomplexity.Understanding the factors modulating the composition of marine ecosystems is paramount for improving restoration and sustainability strategies. In this direction, size-based ecosystem modeling has had a long tradition in marine research. Body size is considered as a 'master trait' scaling with many physiological and behavioral traits, which has been useful in approximating the composition of marine ecosystems. However, the extent to which internal (such as the particular collection of species in a community) and external factors (such as protected areas or temperature variability) affect species composition has not been properly measured (i.e., what body size cannot capture). Yet, this is critical in the face of global environmental change, which continues to cause biodiversity loss and climatic changes. To address this gap, we estimate internal effects by approximating species interactions using a niche overlap framework that estimates the intersection between species’s body size density functions. We integrate these interactions under a Lotka-Volterra dynamics in order to analytically estimate the community composition given a collection of species. We then quantify the extent to which this methodology explains what body size alone cannot. Then, we identify external factors (e.g. climatic variables, human impact) linked to the capacity of species interactions to explain community composition.Peer reviewe