Effects of Ocean Acidification on Species Composition and Biodiversity in the Region of Kongsfjord (Svalbard)

• Main Author: Grandon, Nathalia
• Format: Bachelor Thesis
• Language: English
• Published: Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap 2020
• Subjects: Natural Sciences; Naturvetenskap; Arctic; Arctic Ocean; Svalbard; Kongsfjord; atlantic cod; Kongsfjord*; Ocean acidification; Phytoplankton; polar cod; Copepods
• Online Access: http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-42347

Ocean acidification is a great threat to marine ecosystems and the oceans around the poles are first in line to be affected by the increase in CO2 concentration, effectively damaging the living conditions of marine life present here. This paper analysis and discusses whether studies on the effects of ocean acidification on single species can be used to predict future changes in food web dynamics. The results indicate that by looking at effects on different physiological functions on single species, predictions on how the species in question will cope with a more acidic environment can be made. These predictions can in turn hint on possible changes in the food web. The increase in DOC as well as the shift to smaller and more toxic species of phytoplankton will prove advantageous to bacterioplankton who will play a bigger role in future carbon cycling. The toxic HAB’s could present a hazardous future for primary consumers, but especially secondary consumers. If not affected by the toxicity of the more frequent algal blooms, primary consumers will face negative consequences to the larval recruitment of copepods and shell formation of pteropods by ocean acidification. This would mean a decrease in abundance causing eutrophication and smaller amounts of food sources for fish higher up the trophic cascades, such as the endemic polar cod and the Atlantic cod. Regardless of the general scarcity of data available from these areas, all studies point to a shift in species composition. A clear indication of a future of lower diversity and ultimately an Arctic Ocean with lower ecological resilience.