Bio-optical characteristics of the snow, ice, and water column of a perennially ice-covered lake in the High Arctic

Belzile, Claude; Vincent, Warwick F.; Gibson, John A.E.; Hove, Patrick Van

doi:10.1139/cjfas-58-12-2405

Cited by 27 publications

(40 citation statements)

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“…In Lake Baikal, we found that the light intensity (PAR) just below the ice (0.8 m in thickness) was 40% of that measured at the top of the ice. The large wind fetch of Lake Baikal means that the lake ice is swept relatively clear of snow, which can have a major shading effect on PAR transmission (Belzile et al 2001). The light inhibition of photosynthesis might have occurred even under the ice due to high penetration of solar radiation through the clear ice.…”

Section: Discussionmentioning

confidence: 99%

Seasonal dynamics of primary production in the pelagic zone of southern Lake Baikal

et al. 2003

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We measured primary production by phytoplankton in the south basin of Lake Baikal, Russia, by in situ 13 Cbicarbonate incubations within the period March-October in two consecutive years (1999 and 2000). Primary production was highest in the subsurface layer, possibly due to near-surface photoinhibition of photosynthesis, even under 0.8 m of ice cover in March. Areal primary production varied from 79 mg C m Ϫ2 day Ϫ1 (March) to 424 mg C m Ϫ2 day Ϫ1 (August), and annual primary production was roughly estimated as 75 g C m Ϫ2 year Ϫ1 , both of which are within the lower range of previous estimates. Size fractionation measurements revealed that phytoplankton in the Ͻ20 µm fraction accounted for 72%, 96%, and 85% of total primary production in March, August, and October, respectively. The contribution of picophytoplankton (Ͻ2 µm) to total primary production ranged from 41% to 62%. A large fraction (82%-98%) of particulate organic carbon was associated with particles in the Ͻ20 µm fraction. These results suggest that nano-and picophytoplankton play an important role as primary producers in the pelagic ecosystem of Lake Baikal.

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Section: Discussionmentioning

confidence: 99%

Seasonal dynamics of primary production in the pelagic zone of southern Lake Baikal

et al. 2003

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“…Consequently, the lakes have developed deep thermal maxima over many decades of solar heating . In addition to evidence of long-term lake ice covers from the existence of thermal maxima, these lakes were observed to have a refrozen candled ice cover prior to the onset of melt, which suggests that the ice cover was perennial (Hattersley-Smith et al 1970;Belzile et al 2001). Between 1969 and 1998, these lakes were never reported to have lost their ice cover during the summer beyond melting around the lake shore that created a ''moat'' of variable but limited extent (Bradley et al 1996;Ludlam 1996).…”

Section: Methodsmentioning

confidence: 96%

“…Briefly, Hattersley-Smith et al (1970) used Knudsen bottles, reversing thermometers, and an automatic temperature-depth-salinity recorder; Jeffries et al (1984), Jeffries and Krouse (1985), and M. O. Jeffries unpubl. data used reversing thermometers and measured aliquots from Knudsen bottles with an Endeco refracting salinometer; Ludlam (1996) used a 2-Hz Seacat SBE 19-03 profiler; and Belzile et al (2001) and Van Hove et al (2006) both used a Hydrolab Surveyor 3 profiler. Unpublished profiles provided by M. Retelle were obtained using a temperature and salinity profiler (YSI) down to a depth of 60 m and from a Kemmerer bottle water for salinity at greater depths.…”

Section: Methodsmentioning

confidence: 99%

High Arctic lakes as sentinel ecosystems: Cascading regime shifts in climate, ice cover, and mixing

Mueller

Hove

Antoniades

et al. 2009

Limnology & Oceanography

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Climate and cryospheric observations have shown that the high Arctic has experienced several decades of rapid environmental change, with warming rates well above the global average. In this study, we address the hypothesis that this climatic warming affects deep, ice-covered lakes in the region by causing abrupt, threshold-dependent shifts rather than slow, continuous responses. Synthetic aperture radar (SAR) data show that lakes (one freshwater and four permanently stratified) on Ellesmere Island at the far northern coastline of Canada have experienced significant reductions in summer ice cover over the last decade. The stratified lakes were characterized by strong biogeochemical gradients, yet temperature and salinity profiles of their upper water columns (5-20 m) indicated recent mixing, consistent with loss of their perennial ice and exposure to wind. Although subject to six decades of warming at a rate of 0.5uC decade 21 , these lakes were largely unaffected until a regime shift in air temperature in the 1980s and 1990s, when warming crossed a critical threshold forcing the loss of ice cover. This transition from perennial to annual ice cover caused another regime shift whereby previously stable upper water columns were subjected to mixing. Far northern lakes are responding discontinuously to climate-driven change via a cascade of regime shifts and have an indicator value beyond the regional scale.There is a broad consensus that the world is entering a period of accelerated climate change (Solomon et al. 2007). Anthropogenic emissions of greenhouse gases and the resultant increase in net radiative forcing are widely accepted as the cause of this rapidly changing climate (Hansen et al. 2006). We are now faced with the challenge of evaluating the extent and pace of this change and its effect on the biosphere.Computer models and direct observations (Serreze and Francis 2006) indicate that the highest amplitude and most rapid climate changes are occurring in the Arctic. Although there is considerable variability among regions, the annual average air temperature in the North American continental Arctic increased by 1.06uC decade 21 during the last two decades (Comiso 2003), well above the global average of 0.2uC decade 21 during the same period (Hansen et al. 2006). The thinning and decrease in extent of Arctic sea ice cover (Maslanik et al. 2007) will lead to even more pronounced changes through an albedo-driven positive feedback that would cause Arctic Ocean warming, a further decrease in sea ice extent, and more amplification of high latitude warming.Many reports have shown significant climate change and associated ecosystem effects in the Arctic since the beginning of the short observational period in this region (Serreze et al. 2000). Long-term trends, however, have been difficult to resolve in the Arctic, in part because of the lack of site-specific data and substantial interannual variability in climate, which is exacerbated by the Northern Annular Mode. These factors act to obscure underlying tre...

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“…Incident PAR was 53 and 33 mol photon m –2 day –1 in May and August 2008, respectively (Veillette et al, 2011), and 65 mol photon m –2 day –1 in July 2009. PAR immediately under the ice in May was estimated as described by Belzile et al (2001). We estimated PAR levels at the sampled depths of our study in May and August 2008 and July 2009 ( Table 1 ) based on the albedo and attenuation coefficient measurements from Belzile et al (2001).…”

Section: Methodsmentioning

confidence: 99%

Pyrosequencing analysis of the protist communities in a High Arctic meromictic lake: DNA preservation and change

et al. 2012

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High Arctic meromictic lakes are extreme environments characterized by cold temperatures, low nutrient inputs from their polar desert catchments and prolonged periods of low irradiance and darkness. These lakes are permanently stratified with an oxygenated freshwater layer (mixolimnion) overlying a saline, anoxic water column (monimolimnion). The physical and chemical properties of the deepest known lake of this type in the circumpolar Arctic, Lake A, on the far northern coast of Ellesmere Island, Canada, have been studied over the last 15 years, but little is known about the lake’s biological communities. We applied high-throughput sequencing of the V4 region of the 18S ribosomal RNA gene to investigate the protist communities down the water column at three sampling times: under the ice at the end of winter in 2008, during an unusual period of warming and ice-out the same year, and again under the ice in mid-summer 2009. Sequences of many protist taxa occurred throughout the water column at all sampling times, including in the deep anoxic layer where growth is highly unlikely. Furthermore, there were sequences for taxonomic groups including diatoms and marine taxa, which have never been observed in Lake A by microscopic analysis. However, the sequences of other taxa such as ciliates, chrysophytes, Cercozoa, and Telonema varied with depth, between years and during the transition to ice-free conditions. These seasonally active taxa in the surface waters of the lake are thus sensitive to depth and change with time. DNA from these taxa is superimposed upon background DNA from multiple internal and external sources that is preserved in the deep, cold, largely anoxic water column.

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Bio-optical characteristics of the snow, ice, and water column of a perennially ice-covered lake in the High Arctic

Cited by 27 publications

References 0 publications

Seasonal dynamics of primary production in the pelagic zone of southern Lake Baikal

Seasonal dynamics of primary production in the pelagic zone of southern Lake Baikal

High Arctic lakes as sentinel ecosystems: Cascading regime shifts in climate, ice cover, and mixing

Pyrosequencing analysis of the protist communities in a High Arctic meromictic lake: DNA preservation and change

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