ESTIMATION OF EGERIA DENSA OVERGROWTH POTENTIAL USING ENVIRONMENTAL DNA IN THE GONOKAWA RIVER

Abstract

 Effects of Egeria densa on aquatic ecosystems are major concerns in Japan. It is important to efficiently identify river segments in the entire watershed where the E. densa can be overgrowth. Using environmental DNA (eDNA) analyses, we examined the distribution and abundance of E. densa and the factors that could affect the overgrowth of the target species in the Gonokawa River. In addition, the potential maps of the suitable habitats for E. densa overgrowth were created based on the results. Our results indicated that the riverbed slope and low water temperature time were significantly and negatively related to the eDNA concentrations of E. densa in the study river basin. In addition, based on the potential maps created with the statistical results, the river segments suitable for the E. densa overgrowth were identified in the study river basin.