Copepods are the main group of the zooplankton in Mediterranean pelagic ecosystems, both in terms of abundance and diversity. Not only do copepods play a pivotal role in marine ecosystems, they are also considered as « beacons of climate change ». Nonetheless, estimates of climate change impacts on copepod diversity and community composition are still lacking worldwide. Additionally the uncertainty sources embedded in such climate change projections still need to be better resolved.
Here, for the first time, we estimate the impact of climate change on copepod alpha and beta diversity in the surface of the whole Mediterranean Sea through a comprehensive niche modeling framework. The associated uncertainty sources are identified and their relative contribution were quantified. We show that future climate change may lead to moderate losses in copepod species richness in the Mediterranean basin, with higher decrease in the eastern regions.
Nestedness is the main processes driving the modelled changes in species richness and composition. The choice of the niche model is the main source of uncertainty, far ahead of the emission scenario, the forcings of the circulation model of the number of occurrences used to build the species niche models. Photo by Dr. Stéphane Gasparini.Download high resolution file: ecog_cover_2.pdf