Réponse d'une communauté de diatomées de glace à un gradient de salinité (baie d'Hudson)
Réponse d'une communauté de diatomées de glace à un gradient de salinité (baie d'Hudson)
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硅藻土冰川与盐梯度的反应 (baie dHudson)
DOI：
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发表时间：
1983
期刊：
影响因子：
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通讯作者：
L. Legendre
中科院分区：
文献类型：
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作者：
M. Poulin;A. Cardinal;L. Legendre
海冰为微藻(水生群落)的生长提供了物质支持。几乎所有关于北极和南极冰微生物区系的研究都是在高盐度水域进行的，它们通常报告了非常高的现存量作物。1978年2月至5月，在加拿大魁北克省哈德逊湾(马尼图努克海湾)东南部的15个站点进行了采样。水体的特殊物理条件在从大鲸河口到马尼图努克海峡上游的底层水域建立了盐度梯度，导致冰动力学中的平行梯度。这项研究的主要目的是研究这些梯度对史诗群落的生物量和分类组成的影响。因此，在冰中有两个不同的梯度，一个由控制冰层厚度和定居效率的地表水盐度梯度控制，这引发了Eepontic群落(马尼图努克海峡上游的较高现存量作物)的生物量。此外，冰的盐度梯度影响分类组成(朝着大鲸河河口的微藻分类群数量较少)。在对以物种为基础的观察组进行判别分析后，下垫面水的盐度成为控制物种分布和丰度的一个主要环境变量。因此，除了充足的光照强度和营养供应外，底层水的盐度也是限制冰微生物区系定居和生长的另一个因素。这一因素在沿海和河口冰川水域具有重要的潜在意义。
Sea ice offers a physical support to the growth of microalgae (epontic community). Almost all the studies on ice microflora in the Arctic and the Antarctic have been performed in waters of high salinities, and they generally reported a very high standing crop. From February through May 1978, 15 stations were sampled in the southeastern part of Hudson Bay (Manitounuk Sound), Quebec, Canada. The peculiar physical condition of the water bodies establishes a salinity gradient in the underlying waters from the mouth of the Great Whale River to the upper reaches of Manitounuk Sound, leading to a parallel gradient in the ice dynamics. The main goal of this study was to examine the effect of these gradients on the biomass and the taxonomic composition of the epontic community. Thus, there are two distinct gradients in the ice, one ruled by the surface-water salinity gradient controlling the ice thickness and the settlement efficiency, which triggers the biomass of the epontic community (higher standing crop in the upper reaches of Manitounuk Sound). In addition, the ice salinity gradient influences the taxonomic composition (lower number of microalgae taxa toward the mouth of the Great Whale River). Salinity of the underlying surface waters, following discriminant analyses of species-based clusters of observations, emerges as a major environmental variable controlling the distribution and abundance of species. In addition to adequate light intensity and nutrient supply, salinity of the underlying waters is therefore another limiting factor to the settlement and growth of an ice microflora. This factor is of great potential significance in coastal and esturine glacial waters.