Wu Luhan, Osugi Tomonori, Inagawa Takashi, Okitsu Jiro, Sakamoto Shogo, Minamoto Toshifumi
Graduate School of Human Development and Environment, Kobe University, Kobe City, Hyogo, Japan.
Water Resources Environment Center, Tokyo, Japan.
Mol Ecol Resour. 2024 Jan;24(1):e13875. doi: 10.1111/1755-0998.13875. Epub 2023 Oct 13.
Periodic monitoring can provide important information for the protection of endangered fish, sustainable use of fishery resources and management of alien species. Previous studies have attempted to monitor fish using non-invasive environmental DNA (eDNA) technology, generally employing quantitative PCR to quantify the eDNA concentration. However, the throughput was limited. High-throughput metabarcoding technology can detect the DNA of multiple species simultaneously in a single experiment but does not provide sufficient quantification. In this study, we applied a quantitative metabarcoding approach to simultaneously quantify the eDNA concentration of an entire fish assemblage in a small reservoir over two summer seasons. Traditional surveys were also conducted to investigate the individuals of fish. The eDNA concentrations were quantified using quantitative metabarcoding, and the fish species detected using this approach were highly consistent with the results of traditional fish monitoring. A significant positive relationship was observed between the eDNA concentration and fish species abundance. Seasonal changes in fish community structure were estimated using eDNA concentrations, which may reveal the activity seasons of different fish. The eDNA concentrations of different fish species peaked at different water temperatures, reflecting the differential responses of fish species to this environmental factor. Finally, by detecting outlier eDNA concentrations, the spawning activities of 13 fish species were estimated, 12 of which were roughly consistent with the current knowledge of fish spawning periods. These results indicate that quantitative eDNA metabarcoding with dozens of sampling times is useful for the simultaneous ecological monitoring of multiple fish species.
定期监测可为濒危鱼类保护、渔业资源可持续利用及外来物种管理提供重要信息。以往研究尝试利用非侵入性环境DNA（eDNA）技术监测鱼类，通常采用定量PCR来量化eDNA浓度。然而，其通量有限。高通量宏条形码技术可在单个实验中同时检测多个物种的DNA，但无法提供足够的定量信息。在本研究中，我们应用定量宏条形码方法在两个夏季对一个小型水库中整个鱼类群落的eDNA浓度进行同步量化。还进行了传统调查以研究鱼类个体。利用定量宏条形码对eDNA浓度进行量化，该方法检测到的鱼类物种与传统鱼类监测结果高度一致。观察到eDNA浓度与鱼类物种丰度之间存在显著正相关关系。利用eDNA浓度估计鱼类群落结构的季节性变化，这可能揭示不同鱼类的活动季节。不同鱼类物种的eDNA浓度在不同水温下达到峰值，反映了鱼类物种对这一环境因子的不同响应。最后，通过检测异常的eDNA浓度，估计了13种鱼类的产卵活动，其中12种与当前已知的鱼类产卵期大致相符。这些结果表明，进行数十次采样的定量eDNA宏条形码技术对于同时对多种鱼类进行生态监测很有用。
