Benthic community mapping in the northern Dreki area, Iceland

• Main Author: Jessica Tadhunter 1991-
• Other Authors: Háskóli Íslands
• Format: Thesis
• Language: English
• Published: 2017
• Subjects: Umhverfis- og auðlindafræði; Botndýr; Sjávarmengun; Olíumengun; Loftslagsbreytingar; Norðlægar slóðir; Arctic; Greenland; Svæði; Climate change; Iceland; Ocean acidification
• Online Access: http://hdl.handle.net/1946/26722

The deep Arctic seafloor supports a wide diversity of benthic megafauna that provide important ecosystem services. However, deep-sea Arctic environments are increasingly under threat due to climate change and ocean acidification as well as the ongoing expansion of human activities such as fishing, shipping, and hydrocarbon production into deeper and higher-latitude waters. There is thus a growing need for baseline information on megafauna community composition and distribution, without which assessment of impacts is virtually impossible. This study reviewed the available information on deep-sea megafauna communities in the Greenland-Iceland-Norwegian (GIN) Seas. An in-depth review of 12 studies documented a diverse array of benthic communities and revealed large regional variations in the quantity and quality of information. No information was available for the northern Dreki area in the Icelandic EEZ despite interest in hydrocarbon exploration in this area. This study modelled the distribution of communities at a 10,500 km2 study site located within the northern Dreki area. Acoustic and benthic surveys were carried out at this site in 2008. The benthic data were analysed using multivariate methods, resulting in the identification of five megafauna communities. Random forest was used to model the relationship between communities and variables derived from the acoustic survey data, including depth and backscatter, which enabled the generation of a full-coverage map of predicted community distribution. While this map indicates that the impacts of hydrocarbon operations could greatly alter community structure in the northern Dreki area, further studies using more comprehensive datasets are required to confirm these findings. Hafsbotninn á norðlægum hafsvæðum einkennist af fjölskrúðugu lífríki stórvaxinna botndýra. En þessi norðlægu svæði eru undir auknu álagi af völdum hnattrænnar hlýnunar og súrnun sjávar, sem og auknum athöfnum mannsins, svo sem af völdum veiða, skipaflutninga og olíuvinnslu, oft á miklu dýpi. ...