FUNSEA - Desvendar os impactos funcionais da perda das florestas marinhas num oceano em aquecimento para capacitar a gestão costeira.

Marine Forests (MF) are earning recognition as NBS to mitigate and adapt to CC [1,5], but should be climate resilient to strengthen ecosystem resilience. However, MF are threatened by CC and anthropogenic activities and their composition [7,11RT] and functional role may change with these impacts [6RT]. Therefore, the main objective of the FUNSEA project is to understand the Functional Impacts of Seaweed Loss in a Warming Ocean, by providing innovative trait-based and decision-support frameworks to assess these functional impacts and identify best practises for coastal ecosystem conservation and options for CC mitigation, considering the NBS potential of MF. FUNSEA will assess the changes in seaweed functional diversity from the Portuguese coast exposed to different thermal stress and climate regimes (Fig. 2) in successive steps (Fig. 1): measuring traits; quantifying functional changes affecting ES; inferring community vulnerability/resilience; and developing a decision-based tool that uses functional diversity for scenario projections to support conservation goals and advice on management. The FUNSEA specific goals are to: 1. Develop a critical understanding of the functioning of MF and associated seaweeds under future CC scenarios; 2. Deepen comprehension on the links between seaweed traits and ecological processes and services, incorporating CC mediated changes. 3. Determine experimentally functional thresholds for thermal stress and evaluate how their contribution to ecological processes changes; 4. Test innovative functional metrics to assess the resilience and vulnerability of communities within and across environmental gradients exposed to thermal stress; 5. Inform best practices to protect coastal ecosystems and mitigate CC through the development of CC and management scenarios for MF natural capital and associated ES. 6. Promote dialogue between marine scientists and stakeholders to inform management that safeguard marine biodiversity. 7. Communicate the natural value of MF widely so that conservation measures can be accepted. Overall, we hypothesise that: H1: Functional diversity will decline with rising shore height at all latitudes so that marginal communities (i.e. upper intertidal) are more vulnerable to species loss. However, the rate of decline varies across latitudes. H2: Species turnover will always be greater than functional turnover along the latitudinal gradient, but this difference will decrease over time as changes in species composition progressively alter the functional composition of seaweed assemblages. H3: The balance between loser and winner species will be even across latitudes, but functional diversity will differ as more specialised and unique species will turn out to be CC losers in the north. This reduced redundancy will have a greater impact on ecosystem functioning and services; H4: From north to south, a conservative strategy will evolve towards a more acquisitive strategy, mainly due to the increase in temperature stimulating physiological and ecological processes. This will increase biomass turnover but reduce carbon sink potential and lead to less stable and complex habitats supporting biodiversity and nursery functions (i.e. decline in ES); H5: The contribution of morphologically similar MF species to ES will vary due to differences in lifespan and turnover rates; H6: The position of unique and specialised species in trait space will be crucial for their contribution