Passive eDNA collection enhances aquatic biodiversity analysis.

Area of Science:

• Marine biology
• Molecular ecology
• Environmental science

Background:

• Environmental DNA (eDNA) metabarcoding is crucial for aquatic species detection and biodiversity assessment.
• Current active filtration methods for eDNA collection are time-consuming and require specialized equipment, limiting sample sizes for ecological studies.
• There is a need for more efficient eDNA sampling techniques to address abundance and distribution patterns.

Purpose of the Study:

• To develop and validate a passive eDNA collection method for marine environments.
• To compare the effectiveness of passive eDNA collection with active filtration methods.
• To assess the potential of passive collection for increasing sampling scope in eDNA metabarcoding studies.

Main Methods:

• Passive eDNA collection was performed by submerging positively charged nylon and non-charged cellulose ester filter membranes directly in tropical and temperate marine water columns.
• A universal fish metabarcoding assay was employed to analyze the collected eDNA samples.
• The performance of passive collection was compared against traditional active filtration methods in temperate marine systems.

Main Results:

• Passive eDNA collection demonstrated comparable fish detection rates to active filtration methods in temperate marine environments.
• Passive collection yielded similar estimates of total fish biodiversity as active filtration.
• The study successfully demonstrated passive eDNA collection in both tropical and temperate marine systems.

Conclusions:

• Passive eDNA collection is a viable and effective alternative to active filtration for aquatic biodiversity assessments.
• This simplified method enables significantly greater biological sampling, broadening the scope of ecological research using eDNA metabarcoding.
• Passive eDNA collection offers a promising approach for advancing ecological studies on species abundance and distribution.