Task 2.4: Quantify the impact of ocean acidification on biofilms from rocky habitats

Karen Tait, PML


H0 Elevated CO2 x temperature will have no significant impact on the diversity and functioning of microbial biofilms.

The ecology of rocky shores is relatively well-known and these systems are heavily impacted and responsive to environmental change. The assemblages that colonise these systems rely on allochthonous carbon from the marine environment (filter feeders) and autochthonous production (grazers).

A major source of the autochthonous productivity is in the form of the microbial biofilms, consisting of bacteria and photosynthetic organisms such as cyanobacteria, diatoms, other unicellular algae plus the spores and germinal stages of macro-algae that settle on intertidal substrata.

Many reports have also described enhanced settlement of invertebrate larvae and algal spores on surfaces colonised by bacteria. These microbial-derived inductive agents are not only important for selection of surfaces, but can also trigger metamorphological events in certain species. As microbes are the first colonisers of disturbed surfaces, they are extremely important to studies of potential disturbance and succession under high CO2 conditions. To examine this key component of marine benthic ecology, the specialized microbial settlement panels will be used.