Abstract：
Passive samplers are enabling the scaling of environmental DNA (eDNA) biomonitoring in our oceans, by circumventing the time-consuming process of water filtration. Designing a novel passive sampler that does not require extensive sample handling time and can be connected to ocean-going vessels without impeding normal underway activities has potential to rapidly upscale global biomonitoring efforts onboard the world\'s oceanic fleet. Here, we demonstrate the utility of an artificial sponge sampler connected to the continuous pump underway seawater system as a means to enable oceanic biomonitoring. We compared the performance of this passive sampling protocol with standard water filtration at six locations during a research voyage from New Zealand to Antarctica in early 2023. Eukaryote metabarcoding of the mitochondrial COI gene revealed no significant difference in phylogenetic α-diversity between sampling methods and both methods delineated a progressive reduction in number of Zero-Radius Operational Taxonomic Units (ZOTUs) with increased latitudes. While both sampling methods revealed comparable trends in geographical community compositions, distinct clusters were identified for passive samplers and water filtration at each location. Additionally, greater variability between replicates was observed for passive samplers, resulting in an increased estimated level of replication needed to recover 90 % of the biodiversity. Furthermore, traditional water filtration failed to detect three phyla observed by passive samplers and extrapolation analysis estimated passive samplers recover a larger number of ZOTUs compared to water filtration for all six locations. Our results demonstrate the potential of this passive eDNA sampler protocol and highlight areas where this emerging technology could be improved, thereby enabling large-scale offshore marine eDNA biomonitoring by leveraging the world\'s oceanic fleet without interfering with onboard activities.
摘要：
被动采样器正在实现我们海洋中环境DNA（eDNA）生物监测的缩放，通过规避耗时的水过滤过程。设计一种新型的被动采样器，该采样器不需要大量的样品处理时间，并且可以连接到远洋船只而不会妨碍正常的航行活动，有可能在世界大洋舰队上迅速扩大全球生物监测工作。这里,我们展示了与海水系统连续泵相连的人造海绵采样器的实用性，作为实现海洋生物监测的一种手段。在2023年初从新西兰到南极洲的研究航行中，我们将这种被动采样协议的性能与六个地点的标准水过滤进行了比较。线粒体COI基因的真核生物元编码显示，采样方法之间的系统发育α多样性没有显着差异，两种方法都描绘了随着纬度增加，零半径操作分类单位（ZOTUs）数量逐渐减少。虽然两种抽样方法都揭示了地理社区组成的可比趋势，在每个位置为被动采样器和水过滤确定了不同的簇。此外,对于被动采样器，观察到重复之间更大的变异性，导致恢复90％的生物多样性所需的估计复制水平增加。此外，传统的水过滤无法检测到被动采样器观察到的三个门，而外推分析估计，与所有六个位置的水过滤相比，被动采样器恢复了更多的ZOTU。我们的结果证明了这种被动eDNA采样器协议的潜力，并突出了这种新兴技术可以改进的领域，从而通过利用世界大洋舰队而不干扰船上活动，实现大规模近海海洋eDNA生物监测。
