Physical and chemical limnology of 34 ultra-oligotrophic lakes and ponds near Wynniatt Bay, Victoria Island, Arctic Canada
Physical and chemical limnology of 34 ultra-oligotrophic lakes and ponds near Wynniatt Bay, Victoria Island, Arctic Canada
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加拿大北极地区维多利亚岛温尼阿特湾附近 34 个超贫营养湖泊和池塘的物理和化学湖泊学
DOI：
10.1023/a:1021201704844
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发表时间：
2002
期刊：
影响因子：
2.6
通讯作者：
J. Smol
中科院分区：
文献类型：
--
作者：
N. Michelutti;M. Douglas;D. Lean;J. Smol
对维多利亚岛中北部(加拿大北极)的34个湖泊和池塘进行了研究，以确定这些未经研究的水生生态系统的湖水状况，并作为监测对气候敏感的高纬度地区未来变化的更大研究的一部分提供基线数据。与其他几个北极地区类似，这些湖泊和池塘略微碱性(平均pH=7.6 5)，稀释(平均比电导=96.4μS)，营养物质含量低。湖湖学数据集的显著之处在于湖泊和池塘的超寡营养性质，因为平均磷(1.3μg L−1)和叶绿素a(0.4μg L−1)浓度是北极环境中有记录以来最低的。此外，溶解有机碳(DOC)浓度(通常为-lt；1 mg L−1)比类似纬度池塘的记录低2-3倍。主成分分析(PCA)主要沿着DOC和比电导的梯度以及沿着颗粒氮的次要梯度划分站点，这可能反映了浮游植物和浮游动物生物量的差异。这些营养极少的湖泊和池塘应该会对全球变暖表现出明显的反应。由于DOC起到了天然紫外线辐射屏障的作用，超低营养条件和低DOC水平的结合表明，这些地点内的生物群代表了那些适应高压力环境的生物群。这一地区的湖泊和池塘是理想的监测点，因为它们应该对未来的环境变化特别敏感。
Thirty-four lakes and ponds on north-central Victoria Island (Arctic Canada) were examined in order to characterize the limnological conditions of these unstudied aquatic ecosystems, and to provide baseline data as part of a larger study monitoring future changes in climatically-sensitive high-latitude locations. Similar to several other arctic regions, the lakes and ponds were slightly alkaline (mean pH = 7.65), dilute (mean specific conductance = 96.4 μS), and low in nutrients. What distinguished this limnological data set was the ultra-oligotrophic nature of the lakes and ponds, as mean phosphorus (1.3 μg l−1) and chlorophyll a (0.4 μg l−1) concentrations were amongst the lowest recorded in arctic environments. Also, dissolved organic carbon (DOC) concentrations (often <1 mg l−1) were 2–3 times lower than those recorded for ponds at similar latitudes. Principal components analysis (PCA) separated sites primarily along a gradient of DOC and specific conductance, and along a secondary gradient of particulate nitrogen, likely reflecting differences in phyto- and zooplankton biomass. These ultra-oligotrophic lakes and ponds should show a marked response to global warming. As DOC acts as a natural UV radiation screen, the combination of ultra-oligotrophic conditions and low DOC levels suggests that the biota within these sites are representative of those adapted to living in highly stressful environments. Lakes and ponds in this region make ideal monitoring sites, as they should be especially responsive to future environmental changes.