Dynamics of Lake Michigan Phytoplankton: Recent Changes in Surface and Deep Communities
Dynamics of Lake Michigan Phytoplankton: Recent Changes in Surface and Deep Communities
复制标题
密歇根湖浮游植物的动态：表层和深层群落的最新变化
DOI：
10.1139/f87-063
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发表时间：
1987
期刊：
影响因子：
--
通讯作者：
D. Scavia
中科院分区：
文献类型：
--
作者：
G. Fahnenstiel;D. Scavia
对1982 - 1984年春季等温混合结束（5月）至分层中期（7 - 8月）期间密歇根湖浮游植物动态进行了研究。浮游植物组成由5月硅藻为主（75%的浮游植物碳）向7 - 8月以鞭毛虫为主（71%的浮游植物碳）转变。20世纪80年代夏季鞭毛藻的优势与20世纪70年代夏季蓝藻和绿藻的优势明显不同。浮游动物组成变化和营养供应变化引起的食物网相互作用是两个可能的原因。在热分层开始后，形成了深叶绿素层（DCL）。DCL首先在15-30 m区域发展，7月扩展到25-50 m， 8月扩展到40-70 m区域。1982-84年的DCL比1970年代报告的DCL规模更大，位于水柱更深。这种差异与20世纪80年代发现的光线透明度的增加有关。
Lake Michigan phytoplankton dynamics were studied from the end of spring isothermal mixing (May) through midstratification (July–August) in 1982–84. Phytoplankton composition shifted from a diatom-dominated community (75% of phytoplankton carbon) during May to a phytoflagellate-dominated community (71% of phytoplankton carbon) during July–August. This summer phytoflagellate dominance in the 1980s is distinctly different from the summer blue-green and green algae dominance in the 1970s. Foodweb interactions caused by a changing zooplankton composition and nutrient supply changes were two possible causes. A deep chlorophyll layer (DCL) developed after the onset of thermal stratification. The DCL initially developed in the 15–30 m region and deepended to 25–50 m in July and the 40–70 m region in August. The DCL in 1982–84 was larger in size and located deeper in the water column than those reported from the 1970s. This difference was related to increases in light transparency found in the 1980s that were a r...