Graduate School of Human Development and Environment, Kobe University Kobe City, Hyogo, Japan.
Research Fellow of Japan Society for the Promotion of Science, Tokyo, Japan.
Mol Ecol Resour. 2021 Jul;21(5):1490-1503. doi: 10.1111/1755-0998.13354. Epub 2021 Mar 10.
Understanding the processes of environmental DNA (eDNA) persistence and degradation is essential to determine the spatiotemporal scale of eDNA signals and accurately estimate species distribution. The effects of environmental factors on eDNA persistence have previously been examined; however, the influence of the physiochemical and molecular states of eDNA on its persistence is not completely understood. Here, we performed meta-analyses including 26 previously published papers on the estimation of first-order eDNA decay rate constants, and assessed the effects of filter pore size, DNA fragment size, target gene, and environmental conditions on eDNA decay rates. Almost all supported models included the interactions between the filter pore size and water temperature, between the target gene and water temperature, and between the target gene and water source, implying the influence of complex interactions between the eDNA state and environmental conditions on eDNA persistence. These findings were generally consistent with the results of a reanalysis of a previous tank experiment which measured the time-series changes in marine fish eDNA concentrations in multiple size fractions after fish removal. Our results suggest that the mechanism of eDNA persistence and degradation cannot be fully understood without knowing not only environmental factors but also cellular and molecular states of eDNA in water. Further verification of the relationship between eDNA state and persistence is required by obtaining more information on eDNA persistence in various experimental and environmental conditions, which will enhance our knowledge on eDNA persistence and support our findings.
了解环境 DNA（eDNA）的持久性和降解过程对于确定 eDNA 信号的时空尺度和准确估计物种分布至关重要。先前已经研究了环境因素对 eDNA 持久性的影响；然而，eDNA 的物理化学和分子状态对其持久性的影响尚不完全清楚。在这里，我们进行了荟萃分析，其中包括 26 篇先前发表的关于估计一阶 eDNA 衰减率常数的论文，并评估了过滤器孔径、DNA 片段大小、靶基因和环境条件对 eDNA 衰减率的影响。几乎所有支持的模型都包括过滤器孔径和水温度之间、靶基因和水温度之间以及靶基因和水源之间的相互作用，这意味着 eDNA 状态与环境条件之间复杂相互作用对 eDNA 持久性的影响。这些发现与先前对去除鱼类后海洋鱼类 eDNA 在多个大小分数中的时间序列变化进行的水箱实验的重新分析结果基本一致。我们的研究结果表明，如果不知道水中 eDNA 的环境因素和细胞分子状态，就无法完全理解 eDNA 的持久性和降解机制。需要通过在各种实验和环境条件下获得更多关于 eDNA 持久性的信息来进一步验证 eDNA 状态与持久性之间的关系，这将增强我们对 eDNA 持久性的了解并支持我们的发现。
