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Benthic foraminifera as bio-indicators of chemical and physical stressors in Hammerfest harbor (Northern Norway)
(Journal article; Tidsskriftartikkel; Peer reviewed, 2016-10-01)We investigated benthic foraminiferal assemblages in contaminated sediments in a subarctic harbor of northern Norway to assess their utility as indicators of anthropogenic impacts. Sediments in the harbor are repositories for POPs and heavy metals supplied through discharges from industry and shipping activities. Sediment contaminant concentrations are at moderate to poor ecological quality ... -
Benthic foraminifera as indicators of natural variability and anthropogenic impact
(Doctoral thesis; Doktorgradsavhandling, 2013-11-28)Benthic foraminifera (micro-organism living on the sea-floor) were studied in the southwestern Barents Sea and Hammerfest harbor. The study focused on the response of the micro-organisms to natural and man made environmental changes. The study shows that the southwestern Barents sea is relatively clean, and the foraminifera are only impacted by natural changes. However, in the Hammerfest harbor, ... -
Environmental baselines and reconstruction of Atlantic Water inflow in Bjørnøyrenna, SW Barents Sea, since 1800 CE
(Journal article; Tidsskriftartikkel, 2017-10-28)Metal concentrations, sediment properties and benthic foraminiferal assemblages were investigated in sediment cores in the SW Barents Sea, to reconstruct environmental baselines and natural variability of Atlantic Water inflow since 1800 CE. Metal concentrations correspond to no effect levels and do not influence the foraminifera. Increased Hg and Pb was linked to inflow of Atlantic Water. The data ... -
Identifying past petroleum exploration related drill cutting releases and influences on the marine environment and benthic foraminiferal communities, Goliat Field, SW Barents Sea, Norway
(Journal article; Tidsskriftartikkel; Peer reviewed, 2017-11-01)The present multiproxy investigation of marine sediment cores aims at: 1) Identifying dispersion of petroleum exploration related drill cutting releases within the Goliat Field, Barents Sea in 2006/07 and 2) Assessing past and present influence of drill cuttings on the marine environment. The cores were recovered 5, 30, 60, 125 and 250 m from the drill site in the eastward downstream direction.<p> ... -
Impact of drill cutting releases on benthic foraminifera at three exploration wells drilled between 1992 and 2012 in the SW Barents Sea, Norway
(Journal article; Tidsskriftartikkel; Peer reviewed, 2019-12-04)The aim of this study is to identify the environmental impact of drill cuttings (DC) released around three wells drilled in 1992, 2000 and 2012 in the SW Barents Sea. Foraminiferal assemblages are studied in cores taken along transects <250 m from wells. Well E-1992 shows no impact of DC on foraminifera indicating that low amounts of released DC limit environmental impact. Impact at wells G-2000 and ... -
The marine sedimentary environments of Kongsfjorden, Svalbard: an archive of polar environmental change
(Journal article; Tidsskriftartikkel; Peer reviewed, 2019-09-16)Kongsfjorden, a fjord in north-western Svalbard, is characterized by large environmental gradients driven by meltwater processes along the margins of tidewater glaciers and the inflow of relatively warm Atlantic Water, the main heat source for the European Arctic. These factors make Kongsfjorden a key area to investigate changes in the polar climate–ocean–glacier system and to examine the resulting ... -
Natural variability of benthic foraminiferal assemblages and metal concentrations during the last 150 years in the Ingøydjupet trough, SW Barents Sea.
(Journal article; Tidsskriftartikkel, 2015-12)While today the SW Barents Sea is a relatively un-impacted and uncontaminated area, industrial activities related to the petroleum industry are projected to increase in the coming decades. This makes the area a valuable natural laboratory to establish pre-impacted baselines as a precursor for future seabed monitoring programs. Here we present benthic foraminiferal assemblages and metal concentrations ... -
Open Polar – a global open access portal to research on the polar regions
(Conference object; Konferansebidrag, 2021-11)Research activities and research output, in general, have increased, and keep increasing vastly, and so too is research on the polar regions including Svalbard in the Arctic. Major commercial publishers have built subscription-based services which present research literature for a fee. As Open Science and open access to literature and data is gaining momentum, there is a distinct need for powerful ... -
Spreading of drill cuttings and sediment recovery of three exploration wells of different ages, SW Barents Sea, Norway
(Journal article; Tidsskriftartikkel; Peer reviewed, 2018-07-14)Five stations (≤250 m from the well heads) from three exploration wells of different ages from the SW Barents Sea were studied to investigate the spreading of drill cuttings and sediment quality. Two of the wells were drilled before the restriction of use of oil-based drilling fluids (1993). Elevated concentrations of Ba were found in sediments near all the wells with the highest concentrations ... -
Variability of present and past PAH concentrations in sediments of the SW Barents Sea
(Journal article; Tidsskriftartikkel; Peer reviewed, 2015-10-09)The concentration and distribution of polyaromatic hydrocarbons (PAHs) in surface and subsurface sediment samples from Tromsøflaket and Ingøydjupet, southwestern Barents Sea, were investigated in order to provide insight into the levels and origins of PAHs in a region with petroleum activities. PAH profiles in sediments were evaluated in context with sediment grain size and total organic carbon ...
