Living (Stained) Benthic Foraminifera and their Response to the Seasonal Hydrographic Cycle, Periodic Hypoxia and to Primary Production in Havstens Fjord on the Swedish West Coast
Living (Stained) Benthic Foraminifera and their Response to the Seasonal Hydrographic Cycle, Periodic Hypoxia and to Primary Production in Havstens Fjord on the Swedish West Coast
复制标题
瑞典西海岸哈夫斯滕斯峡湾活体（染色）底栖有孔虫及其对季节性水文循环、周期性缺氧和初级生产的响应
DOI：
10.1006/ecss.2000.0695
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发表时间：
2000
影响因子：
2.8
通讯作者：
Kjell Nordberg
中科院分区：
文献类型：
--
作者：
Mathias Gustafsson;Kjell Nordberg
瑞典西海岸的Havstens峡湾是一个有底的峡湾，其特征是强烈的分层和停滞的底层水，周期性地出现缺氧（0-2 ml l−1）或缺氧（≤0 ml l−1）条件。Havstens峡湾的深水更新每年都会发生，主要是在冬季或春季。本研究的目的是发现生活底栖有孔虫如何响应水文变化，周期性缺氧和初级生产力的变化。1993年8月至1994年12月进行了一系列每月水文测量和沉积物取样。采样进行了四个不同的网站沿着深度样带（12，20，30和40米）。叶绿素a的月值从水面下降到15米。随着水深的增加，有孔虫动物群从多样性低的咸水动物群，到多样性和丰富的动物群，再到多样性低和稀少的动物群，其特点是物种耐缺氧。在最深的网站（40米）Elphidium magellanicum和Apriphouthia fusiformis生存五个月的缺氧或接近缺氧的条件。在30米的周期性缺氧条件是严重的，足以防止丰富的底栖大型动物建立，但有足够的氧气丰富多样的有孔虫动物群茁壮成长。在有氧条件下，新鲜沉积的浮游植物似乎是有孔虫的重要食物来源。
Havstens Fjord on the Swedish west coast is a silled fjord that is characterized by strong stratification and stagnant bottom-water with periodically occurring hypoxic (0–2 ml l−1) or anoxic (≤0 ml l−1) conditions. Renewal of Havstens Fjord's deep-water occurs every year, mostly during winter or spring. The aim of this study was to discover how living benthic Foraminifera respond to hydrographic variations, periodic oxygen deficiency and variations in primary production. A long series of monthly hydrographic measurements combined with sediment sampling were performed from August 1993 to December 1994. Sampling was carried out at four different sites along a depth transect (12, 20, 30 and 40 m). Monthly values of chlorophyll a from the water surface down to 15 m were obtained. With increasing water depth, the foraminiferal fauna changed from a low diverse brackish fauna, through a diverse and abundant fauna, to a low diversity and sparse fauna characterized by species tolerant of oxygen depletion. At the deepest site (40 m) Elphidium magellanicum and Stainforthia fusiformis survived five months of anoxic or near anoxic conditions. At 30 m the periodic hypoxic conditions were severe enough to prevent a rich benthic macrofauna establishing, but there was enough oxygen for an abundant and diverse foraminiferal fauna to thrive. Under oxic conditions, freshly sedimented phytoplankton seem to be an important food source for the Foraminifera.