Assessing the response of microbial communities to drivers of global change
As a graduate student, I focused on the response of marine microbial communities to extreme disturbance events and other vectors of climate change.
As study system, I used photosynthetic microbial communities forming biofilms on rocky shores. Along Mediterranean coasts, these communities are mostly composed of cyanobacteria and diatoms embedded, together with heterotrophic bacteria, in a dense polysaccharid matrix. Photosynthetic biofilms are a vital component of rocky intertidal habitats, contributing to primary production, providing food for many grazers and influencing settlement of the dispersive larvae of many sessile invertebrates. Conveniently, their temporal dynamics can be assessed non-destructively using in situ remote sensing techniques based on the spectral properties of chlorophyl a, the most important photosynthetic pigment found in these unicellular organisms.
The core project of my PhD was urged by the need to understand how a neglected aspect of climate change, i.e. the increase in the frequency of extreme events, would impact on photosynthetic biofilms. In particular, I was interested in how the legacy effects of extreme might be different depending on the timing of such events. By manipulating the occurrence of series of extreme disturbances in the field, we showed that extreme events close in time disrupt the coupling between past and present microbial dynamics, ultimately increasing the probability of observing a regime shift from photosynthetically active biofilms to bare rock.
Read more about this project here: