Using an optical plankton counter to determine the size distributions of preserved zooplankton samples
Using an optical plankton counter to determine the size distributions of preserved zooplankton samples
复制标题
使用光学浮游生物计数器确定保存的浮游动物样本的大小分布
DOI：
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发表时间：
1999
期刊：
影响因子：
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通讯作者：
B. Twining
中科院分区：
文献类型：
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作者：
S. Beaulieu;M. M. Mullin;V. T. Tang;Solana Pyne;A. King;B. Twining
为了检查群落组成和生物量的波动，需要对浮游动物进行长时间序列和/或广泛的空间观测。我们测试了实验室光学浮游生物计数器 (OPC) 在确定大量保存的浮游动物样本的大小谱和生物量方面的效用。加州洋流地区各种分类群的 OPC 大小测量值与视觉测量值密切相关 (r2 = 0.80)。尽管长期保存的生物体可能会破碎，但约 800 个超过 10 年的样本的总生物体积趋势与收集后几周内测量的位移体积一致。一项手动破坏磷虾的实验室测试表明，大型浮游动物的 OPC 计数对于中度破碎来说是稳健的。福尔马林保存对甲壳类浮游动物的最大影响是增加了不透明度，导致其比活着时测量的数字尺寸增加了 3-25%。福尔马林保存显着降低了肉眼测量的凝胶状浮游动物的生物体积，但由于不透明度的补偿性增加，并没有改变 OPC 测量的大小。作为使用 OPC 分析大量保存样本的优势的示例，我们检查了 (i) 1984 年巡航期间占据的超过 100 个站点中三个尺寸级别的生物量与叶绿素 a 的正相关性，以及 (ii) 1981 年和 1984 年来自加利福尼亚洋流区域的约 800 个样本中按尺寸分级的浮游动物生物量的沿岸模式。
Long time series and/or spatially extensive observations of zooplankton are needed in order to examine fluctuations in community composition and biomass. We tested the utility of a laboratory optical plankton counter (OPC) in determining the size spectra and biomasses of a large number of preserved zooplankton samples. OPC size measurements of a variety of taxa from the California Current region were well correlated with visual measurements (r2 = 0.80). Although organisms preserved for long time periods may fragment, trends in total biovolumes of ~800 samples that were >10 years old were consistent with displacement volumes measured just weeks after collection. A laboratory test in which euphausiids were damaged manually indicated that OPC counts of large zooplankton are robust to moderate fragmentation. The greatest effect of formalin preservation on crustacean zooplankton was increased opacity, resulting in an increase of 3-25% over the digital sizes measured when alive. Formalin preservation significantly reduced the biovolume of gelatinous zooplankton measured visually, but did not change the size measured by the OPC due to the compen- sating increase in opacity. As examples of the advantage of using the OPC to analyze a large number of preserved samples, we examined (i) the positive relationship of biomass to chlorophyll a in three size classes at >100 stations occupied during a 1984 cruise and (ii) the longshore pattern of size-frac- tionated zooplankton biomass in ~800 samples from the California Current region in 1981 and 1984.