Environmental DNA-based biodiversity profiling along the Houdong River in north-eastern Taiwan

Area of Science:

• Ecology
• Genomics
• Biodiversity Science

Background:

• The Houdong River in Taiwan, a 9 km system flowing from 860m elevation to the Pacific, represents typical Taiwanese fluvial systems.
• This research introduces the first species diversity assessment of the Houdong River system, utilizing environmental DNA (eDNA) metabarcoding.
• The study generated species occurrence data and associated DNA sequences from riverine eDNA samples.

Purpose of the Study:

• To determine eukaryotic species occurrences in the Houdong River ecosystem using eDNA analysis.
• To establish a standardized and replicable metabarcoding eDNA data template for the scientific community, especially in Taiwan.
• To provide foundational data for future species and habitat monitoring in the river system.

Main Methods:

• Collected 12 water samples from the Houdong River.
• Performed eDNA metabarcoding analysis on collected samples.
• Identified species occurrences by matching DNA sequences to databases like the Global Biodiversity Information Facility (GBIF).

Main Results:

• Generated an average of 1.5 million reads per sample.
• Classified 432 Operational Taxonomic Units (OTUs) from a total of 2,734 sequences.
• Documented 1,356 species occurrences with matches in GBIF.

Conclusions:

• The generated datasets are crucial for future biodiversity and habitat monitoring in the Houdong River.
• These findings support regional ecological studies, particularly concerning freshwater ecosystems under global change.
• The established eDNA data template promotes standardized and reproducible biodiversity assessments.