Data from Ershova E, Wangensteen OS, Descoteaux R, Barth-Jensen C, Præbel K. 2021. Metabarcoding as a quantitative tool for estimating biodiversity and relative biomass of marine zooplankton

We explored an enhanced quantitative approach by metabarcoding whole zooplankton communities using a highly degenerate primer set for the mitochondrial marker COI and compared the results to biomass estimates obtained using the traditional morphological approach of processing zooplankton samples. As expected, detected species richness using the metabarcoding approach was 3-4 times higher compared to morphological processing, with the highest differences found in the meroplankton fraction. About 75% of the species identified using microscopy were also recovered in the metabarcoding run. Within the taxa detected using both approaches, the relative numbers of sequence counts showed a strong quantitative relationship to their relative biomass, estimated from length-weight regressions, for a wide range of metazoan taxa. The highest correlations were found for crustaceans and the lowest for meroplanktonic larvae. Our results show that the reported approach of using a metabarcoding marker with improved taxonomic resolution, universal coverage for metazoans, reduced primer bias and availability of a comprehensive reference database, allow for rapid and relatively inexpensive processing of hundreds of samples at a higher taxonomic resolution than traditional zooplankton sorting. The described approach can therefore be widely applied for monitoring or ecological studies.

本研究通过采用高度退化的引物集对全浮游动物群落进行元条形码测序，并对其结果与运用传统形态学方法处理浮游动物样本所得的生物量估计值进行了比较。如预期所示，元条形码方法检测到的物种丰富度是形态学处理的3-4倍，其中在浮游生物部分差异最为显著。使用显微镜鉴定的约75%物种在元条形码分析中亦得以恢复。在两种方法均检测到的分类群中，序列计数相对数量与其相对生物量（通过长度-重量回归估计）之间显示出强烈的定量关系，这一关系适用于广泛的动物门类。其中，甲壳动物的相关性最高，而浮游幼虫的相关性最低。我们的研究结果表明，采用具有改进分类分辨率、针对动物门类的广泛覆盖、减少引物偏差以及提供全面参考数据库的元条形码标记方法，能够实现数百个样本的快速且相对经济的处理，其分类分辨率高于传统的浮游动物分类。因此，所描述的方法可广泛应用于监测或生态学研究。