Effects of temperature regime on primary producers in Icelandic geothermal streams
Effects of temperature regime on primary producers in Icelandic geothermal streams
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DOI：
10.1016/j.aquabot.2011.08.003
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发表时间：
2011-11-01
期刊：
影响因子：
1.8
通讯作者：
Moss, Brian
中科院分区：
文献类型：
--
作者：
Gudmundsdottir, Rake;Gislason, Gisli Mar;Moss, Brian
八个相邻的亚北极流始终不同的温度，但大致相似的化学，除了电导率和相关的pH值的一些差异，被用来调查温度制度对初级生产者群落结构的影响。放牧的无脊椎动物也考虑到检测可能对初级生产者的影响。（苔藓植物）只观察到在温暖的溪流，其覆盖率与温度呈正相关。苔类植物Jungermannia exsertifolia（Steph.）在温暖的溪流中不见，在寒冷的溪流中也很少见。在生物量上，F. antipyretica与石生叶绿素a浓度呈负相关，可能是由于来自brabrites的遮蔽和/或藻类和brabrites之间对营养物的竞争。石生藻类和硬枝藻生物量与主要食草动物的密度无关，绿色藻类的生物量在所有溪流中均较高。蓝藻的生物量是最大的在最冷的流，并在两个中间温暖的流。硅藻的生物量是低的蓝藻和绿色藻类的生物量相比，在所有的流，除了在两个最温暖的流，在那里最高的硅藻生物量occurrent.Regularized典型相关分析（RCCA）分类的基础上，所有的初级生产者组合和无脊椎动物表明，温暖的流（16.7-22.2摄氏度）是彼此相似。它还表明，较冷的流（6.6-13.2摄氏度）与较温暖的流不同，并且由于电导率的差异而彼此不同。温度和电导率是最有影响力的变量，在确定整体流的多样性。(C)2011 Elsevier B. V.保留所有权利。
Eight adjacent sub-arctic streams with consistently different temperatures but broadly similar chemistry, other than some differences in conductivity and linked pH, were used to investigate effects of temperature regime on the structure of primary producer communities. Grazing by invertebrates was also taken into account to detect possible effects on the primary producers.The moss species Fontinalis antipyretica Hedw. (Bryophyta) was only observed in the warmer streams and its cover was positively linked with temperature. The liverwort Jungermannia exsertifolia (Steph.) was absent from the warmer streams and scarce in the colder streams. The biomass of F. antipyretica was inversely correlated with concentration of epilithic chlorophyll a, possibly due to shading from the bryophyte and/or competition between algae and bryophytes for nutrients. Epilithic algae and bryophyte biomass were not related to density of the main grazer, Radix peregra Muller (Gastropoda).A high biovolume of green algae (Chlorophyta) occurred in all streams. The biovolume Cyanobacteria was greatest in the coldest stream and in the two intermediately warm streams. Diatom biovolume was low compared with the biovolumes of Cyanobacteria and green algae in all streams, except in the two warmest streams, where the highest biovolume of diatom occurred.Regularized Canonical Correlation Analysis (RCCA) classification based on all primary producer assemblages and invertebrates indicated that warm streams (16.7-22.2 degrees C) were similar to each other. It also showed that the colder streams (6.6-13.2 degrees C) were different from the warmer streams and from each other because of differences in conductivity. Temperature and conductivity were the most influential variables in determining overall stream diversity. (C) 2011 Elsevier B.V. All rights reserved.