Seasonal and Regional Controls of Phytoplankton Production along a Climate Gradient in South-West Greenland During Ice-Cover and Ice-Free Conditions
Seasonal and Regional Controls of Phytoplankton Production along a Climate Gradient in South-West Greenland During Ice-Cover and Ice-Free Conditions
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DOI：
10.1657/aaar0015-003
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发表时间：
2016-02
期刊：
影响因子：
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通讯作者：
E. Whiteford;Suzanne McGowan;Suzanne McGowan;Christopher D. Barry;N. Anderson
中科院分区：
文献类型：
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作者：
E. Whiteford;Suzanne McGowan;Suzanne McGowan;Christopher D. Barry;N. Anderson
格陵兰岛西南部地区的地理面积很小（<180 km），气候自然梯度很大。温度和降水量的变化导致了三个离散位置（冰盖边缘、内陆和海岸）湖沼学的显著差异。从每个位置的复制湖泊进行采样的物理（温度，光），化学（溶解氧，pH值，电导率，营养物质），和生物（叶绿素a [叶绿素a]，光合色素）变量在12个月内的三个场合：2010年7月至8月，2011年4月至5月，2011年6月至7月跨越冰盖。冰物候的变化与气候梯度，然而，浮游植物的生产和群落组成并没有不同的区域。大规模的季节性波动的温度和营养物质的可用性是最强的浮游植物生产的预测，从硝酸盐到磷控制生产之间的冰盖和无冰条件的转变。潜在的季节性驱动因素，预测生产的变量是独特的每个位置冰盖边缘（可溶性活性磷），内陆（温度），海岸（硅酸盐），并反映当地的差异，养分供应。从目前的研究结果有重要的后果时，控制浮游植物生产在北极湖泊推断从数量有限的网站，但放大代表泛北极的趋势。
ABSTRACT Across a small geographic area (<180 km), the region of South-West Greenland covers a natural climate gradient. Variation in temperature and precipitation result in marked differences in limnology at three discrete locations: ice sheet margin, inland, and the coast. Replicate lakes from each location were sampled for physical (temperature, light), chemical (dissolved oxygen, pH, conductivity, nutrients), and biological (chlorophyll a [Chl a], photosynthetic pigments) variables on three occasions within a 12-month period: July–August 2010, April–May 2011, and June–July 2011 spanning ice cover. Variation in ice phenology was linked to the climate gradient; however, phytoplankton production and community composition did not differ regionally. Large-scale seasonal fluctuations in temperature and nutrient availability were the strongest predictors of phytoplankton production, with a shift from nitrate to phosphorus controlled production between ice-cover and ice-free conditions. Underlying seasonal drivers, variables predicting production were unique to each location—ice sheet margin (soluble reactive phosphorus), inland (temperature), and coast (silicate)—and reflect local differences in nutrient availability. Results from the current study have important consequences when controls over phytoplankton production in Arctic lakes are inferred from a limited number of sites, but up-scaled to represent pan-Arctic trends.