The European seaweed cultivation sector is in a transition phase with the rise of seaweed aquaculture due to an increased interest in seaweed resources. Identifying regions with optimal growth conditions for the cultivation of specific seaweed species contributes to the cultivation process. An understanding how these regions evolve under climate change is required to ensure favorable growth conditions on the long-term. In the present research, regions with favorable growth conditions for specific seaweed species were identified by combining physiological and environmental data in a mechanistic niche model. The outcome of the mechanistic model is a species-specific response, the habitat suitability, which quantifies growth as a function of the temperature, salinity, light and nutrient requirements of the seaweed species. Habitat suitability was quantified in European marine waters for brown seaweeds (i.e. Fucus serratus, F. vesiculosus, Ascophyllum nodosum, Saccharina latissima, Laminaria digitata, Laminaria hyperborea) and red seaweeds (i.e. Chondrus crispus, Gracilaria gracilis, Furcellaria lumbricalis). The model was validated using independent distribution data and the validation statistic was good (area under the curve; AUC > 0.8) for five out of nine species and fair (0.6 < AUC < 0.8) for the remaining four species. The warm-temperate region extending from the coast of Portugal to the south coast of Brittany is currently a suitable habitat for most of the studied species. Due to climate change, we predict that the most optimal environmental conditions will shift northwards, i.e. 110 to 635 km by 2100, depending on the climate scenario. The results of the present study can be used to: (1) select target species for seaweed aquaculture in a specific marine region; (2) select sites for long-term, optimal growth conditions of the specific seaweed species in this study. As such, our results contribute to the decision making process in marine spatial planning and blue growth prioritization. |
