Limnologists generally sample during the day. Consequently, many estimates of lake ecosystem processes are derived from daytime samples. Zooplankton, which play critical roles in many such processes, are typically sampled during the day in the pelagic zone, although they commonly exhibit diel vertical and horizontal migration. Demographic estimates using day pelagic sampling may be biased depending on the type and extent of migration. We compiled 870 paired night‐day zooplankton samples from the literature and found that crustacean zooplankton had, on average, 255% and 125% greater density and biomass, respectively, at night compared to day. Although limnologists have been aware that night zooplankton estimates are often higher than day estimates, our results provide quantitative estimates of the differences. Such underestimates from daytime sampling are alarming and call into question ecological rate processes derived from sampling zooplankton during the day.

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我们应该在晚上采样浮游动物吗？

免疫学家通常在白天取样。因此，许多湖泊生态系统过程的估计都来自白天的样本。尽管浮游动物通常表现出diel垂直和水平迁移，但它们在浮游动物中扮演着重要角色，尽管它们通常表现出diel垂直和水平迁移，但它们通常是在浮游带中白天进行采样的。使用日间浮游采样的人口估计可能会有所不同，具体取决于迁移的类型和程度。我们从文献中收集了870个成对的夜间浮游动物样本，发现与白天相比，甲壳类浮游动物的夜间密度和生物量分别平均分别增加了255％和125％。尽管森林学家已经意识到夜间浮游动物的估计往往高于白天的估计，但我们的结果提供了差异的定量估计。