State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, Jiangsu 210023, China.
State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, Jiangsu 210023, China.
Environ Int. 2020 Jan;134:105230. doi: 10.1016/j.envint.2019.105230. Epub 2019 Nov 5.
Aquatic ecosystems are monitored worldwide using a range of biological quality elements that are morphologically identified. The environmental DNA (eDNA)-based approach has unprecedented advantages (e.g., high throughput, high efficiency and low cost) for biodiversity surveys in both freshwater and marine ecosystems compared with traditional sampling and image recognition. The use of eDNA has been mostly limited to biodiversity estimation, how to apply the eDNA approach in assessing the ecological health status is largely unexplored. Here, using zooplankton as an example, we examined the application of eDNA monitoring for ecological status assessment in an aquatic ecosystem. The results showed that eDNA monitoring reflected the spatial and temporal variations in zooplankton structure. Both species composition and bio-interactions varied significantly between sampling seasons (dry, normal and wet). A total of 60 different zooplankton indices were calculated based on eDNA monitoring and most of these indices were highly correlated with the level of water pollution, which was indicated by the water quality index in one or all three seasons. Both qualitative and quantitative eDNA-based biological indices were correlated with water quality. The season-dependent eDNA zooplankton integrity index (IZI) reflected the ecological status, and this method improves the timeliness of bioassessment.
水生生态系统在全球范围内使用形态学识别的一系列生物质量要素进行监测。与传统的采样和图像识别相比，基于环境 DNA（eDNA）的方法在淡水和海洋生态系统的生物多样性调查中具有前所未有的优势（例如，高通量、高效率和低成本）。尽管 eDNA 的应用主要局限于生物多样性估计，但如何将 eDNA 方法应用于评估生态健康状况在很大程度上仍未得到探索。在这里，我们以浮游动物为例，研究了 eDNA 监测在水生生态系统生态状况评估中的应用。结果表明，eDNA 监测反映了浮游动物结构的时空变化。在采样季节（旱季、正常季和雨季）之间，物种组成和生物相互作用均有显著差异。根据 eDNA 监测计算了 60 个不同的浮游动物指数，其中大多数指数与水污染水平高度相关，这由一个或所有三个季节的水质指数来表示。定性和定量的基于 eDNA 的生物指数均与水质相关。依赖季节的 eDNA 浮游动物完整性指数（IZI）反映了生态状况，这种方法提高了生物评估的及时性。
