Effects of Oil and Chemically Treated Oil on Primary Productivity of High Arctic Ice Algae Studied <i>in Situ</i>
DOI:
https://doi.org/10.14430/arctic1820Keywords:
Algae, Canada. Baffin Island Oil Spill Project, Chlorophyll, Environmental impacts, Marine oil spills, Oil spill dispersants, Phytoplankton, Plant ecology, Primary production (Biology), Sea ice, Sea ice ecology, Hatt, Cape, waters, Nunavut, Ragged ChannelAbstract
Control data on the ice algal bloom at Cape Hatt, northern Baffin Island, during 18 May-2 June 1982 were typical of those at other arctic locations. Ice algae were dominated by pennate diatoms (80% of total cells), particularly Nitzschia grunowii (55%) and N. frigida (15%). In various locations and sampling periods, cell densities ranged from 1.7-384.7 x 100,000,000 cells/sq m, and chlorophyll a concentrations ranged from 3.4-16.7 mg/sq m, both increased over the study period. Mean productivity rates based on particulate radiocarbon fixed were from near zero to 2.95 mg C/sq m/h. Dissolved organic radiocarbon concentrations were almost always higher than particulate radiocarbon concentrations, probably because of cell rupture. Total (dissolved + particulate) productivity rates were up to 12.7 mg C/sq m/h, with an overall mean of 4.4 mg C/sq m/h in control samples. Productivity and productivity per unit chlorophyll increased during May and decreased slightly by 1-2 June. Undisturbed, enclosed areas of the under-ice surface were treated with oil on 23-24 May. Dispersed oil (Venezuela Lagomedio crude + Corexit 9527, BP CTD, or BP 1100 WD) was in contact with the ice for 5 h, whereas untreated oil and solidified oil (BP treatment) remained in the enclosures for the duration of the study (12 days post-treatment). Sampling was carried out in areas where oil contacted the ice and moved away or in areas near oil that remained in contact with the under-ice surface. Five hours after treatment, oil concentrations in the water within the enclosures were similar (0.15-0.28 ppm) in untreated oil, solidified oil and control enclosures. ... No adverse effects of any oil treatment on ice algae were detected in analyses of group composition, cell densities, chlorophyll a concentrations, productivity, productivity /chlorophyll or ratios calculated to standardize for light effects. Untreated and solidified oil may have stimulated ice algal growth and productivity near ... the oiled areas.
Key words: Arctic, ice algae, productivity, oil effects, dispersed oil effects, solidified oil effects, Baffïn Island
