The impact of climate change driven multiple stressors on UK intertidal macroalgae

Many of the individual impacts of climate change have been studied, but to-date there is little information on the consequences of single, and even less on multiple stressors on macroalgae species. Current information mainly focuses on Kelp, and most pioneering work has been carried out in Australia with little information on the impacts of these stressors on macroalgae in the UK. Potential impact on UK species may well be significant, particularly as many cold-water species are being constrained to cooler waters. Not only is there a lack of information on how intertidal macroalgae in the UK may cope with climate change, there is no information on how a combination of predicted stressors may impact them. This project aims to investigate the impact of multiple stressors on UK non-kelp species, with a focus on a variety of common species to provide an inventory of susceptibility which will be combined with UK climate-based predictions to model future distributions. This may well result in a change in dominant species, which may have a significant impact on the ecosystem and therefore both its functions and services.

The wider context of this project impinges on the "blue carbon budget" of coastal ecosystems. While often under-rated, intertidal and shallow sub-tidal macroalgae make a considerable contribution to local and regional carbon fixation and the fate of this carbon is not well explained. The potential loss of this carbon sink would mark a significant reduction in the value of ecosystem services to the coastal zone and hence the understanding of the effects of multiple stressors on common algae is timely and important.


The importance of this research is based on the novel application of multiple stressors on intertidal macroalgal communities. This project will improve fundamental understanding of intertidal macroalgal ecology under the pressures of global change. Specifically, their responses to changes in dose and sequence of multiple stressors. These responses will be examined both in the lab followed by in the field to understand the impacts on associated communities and combined with other research to predict distributional changes of key intertidal algal species. This has importance for intertidal ecology and the ecosystem services that such systems provide to society. Information from this work will have both commercial (seaweed harvesting) and management and regulation (SNH, Marine Science Scotland) for the future resilience and protection of these habitats. Output from this research has implications for seaweed harvesting in Scotland. Significant changes in seaweed distribution and health could have detrimental impacts on small and isolated communities.