2025/05/20 by Sijiu Zhang, Zaoli Yang, Ruxia Qiao +5 · 1 voice
Biochemistry, Genetics and Molecular Biology · Environmental Science · #Environmental DNA in Biodiversity Studies #Fish Ecology and Management Studies #Identification and Quantification in Food
paper · doi:10.1080/15715124.2025.2501650
openalex publication_date 2025/05/20 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/30
Monitoring fish communities is essential for assessing the health and functioning of mountainous river basins, providing valuable insights for their effective management. Environmental DNA (eDNA) analysis has emerged as a powerful tool in surveying fish communities; however, its application in river health assessment is limited by uncertainties regarding eDNA decay characteristics. To address this, we conducted field experiments in the Heishui River using Homatula variegata as the target species to explore the relationships among its biomass, eDNA copy number, and habitat factors, employing Pearson correlation, generalized linear models (GLM), and generalized additive models (GAM) for quantitative analysis. The results revealed that the suspended sediments had the greatest impact on eDNA analysis accuracy. Further indoor experiments revealed that suspended sediment degrades eDNA through microbial degradation and physical damage, with the latter being dominant and the eDNA decay rate increased as suspended sediment concentration increased. Notably, when the concentration reached 1000 mg/L, microbial degradation became a significant contributor to eDNA decay. In conclusion, our study highlights the critical importance of considering suspended sediment concentrations when utilizing eDNA analysis for the health assessments of mountainous river basins. This understanding enhances the reliability and applicability of eDNA as a tool for river health management.