Dugno bendrijų struktūra besitraukiančio ledyno pakraštyje vakarų Svalbarde, Arktyje /

• Main Author: Medelytė, Saulė
• Other Authors: Šiaulys, Andrius
• Format: Master Thesis
• Language: Lithuanian; English
• Published: Institutional Repository of Klaipeda University 2021
• Subjects: benthic communities; underwater video; video mosaics; Arctic fjords; glacier; Svalbard
• Online Access: https://vb.ku.lt/KU:ELABAETD95930967&prefLang=en_US

For the last decades' temperatures in the Arctic, fjords increased dramatically. Due to the warming climate, glaciers in Svalbard are not forming fast enough during winter, which leads to a winter ice area loss trend close to 10 percent per decade since 1979 (Onarheim et al., 2014). Increased melting and retreat of glaciers on Svalbard leads to the release of coastal marine habitats in the upper sublittoral for colonization by benthic macroorganisms where ice scouring was a limiting factor (Węsławski et al. 2011). Benthic communities near retreating glaciers are also being affected by sediment stability, larger inorganic particle concentration, sedimentation rate, and amount of organic matter in sediments (Wlodarska-Kowalczuk, Pearson, 2004). The study of the benthic structure under these pressures is important for understanding the processes occurring in the Arctic. The majority of benthic studies in the Arctic, including Svalbard, were done in deeper depths (100-1000m), with the main focus on easily accessible large fjords and bays using large ships and traditional sampling techniques. However, complex bottom topography and the presence of floating ice significantly complicates the use of traditional sampling methods, forcing us to look for alternative approaches. One such technique is underwater visual technology, which has grown in popularity in recent decades based on its effectiveness in hard-to-reach places. In this work, it will be demonstrated that the use of an underwater video mosaic based on video filming along transects in the upper sublittoral can be a reliable method for identifying communities of visible macro-fauna. This work aimed to assess the structure of benthic communities on the West coast of Svalbard in melting ice and ice-free zones and to determine the regularities of the structure of these communities or functional groups in terms of the melting glacier and geographical location. Underwater video filming was carried out in July-August 2018-2019 in the upper sublittoral (2 –65 m) of ...