On 25 October at 10:15 Anneliis Peterson will defend her doctoral theis „Benthic biodiversity in the north-eastern Baltic Sea: mapping methods, spatial patterns, and relations to environmental gradients“.
Senior Research Fellow Kristjan Herkül, Estonian Marine Institute
Senior Research Fellow Martynas Bučas, University of Klaipeda Ülikool, Lithuania
Biodiversity is important for keeping marine ecosystem functionality under changing environmental conditions. The human use of marine areas is increasing worldwide and intensively used marine areas are under increasing pressures. Decrease of marine biodiversity has already taken place. Therefore, knowledge about spatial patterns of biodiversity and its connections with environmental gradients is crucial to detect and follow changes in biodiversity and to form a well-informed basis for the protection and management of marine resources. In this study, the distribution of species richness of seabed macrovegetation and macroinvertebrates was modeled in the Estonian marine area based on previous point-wise sampling data and map layers of environmental variables (water depth, salinity etc). Highest biodiversity values were detected in the western Estonia archipelago. Potential changes of species richness in the conditions of future climate change were also estimated by modeling. It was found that biodiversity of both seabed flora and fauna will probably decrease across Estonian sea area. Modeled benthic biodiversity layers were further used to test the relationships between underwater biodiversity and shore geomorphology and it was shown that differences in the benthic biodiversity values close to different geomorphological shore types exist. Methodology for mapping seabed substrate and biota using acoustic scanning (sonar), underwater video and mathematical modeling was developed. Compared to the previous point-wise mapping the new sonar- and modelling-based methodology enables mapping of seabed substrate and biota with significantly higher resolution. To facilitate the use of spatial data of biodiversity and other nature values (benthic species, seals, birds) in marine management, marine environmental vulnerability (EVP) and risk (ERP) profiles were developed. EVP identifies environmentally vulnerable areas and ERP identifies areas where environmental risks are highest.