Quantitative assessment of reef foraminifera community from metabarcoding data

Area of Science:

• Marine Biology
• Ecology
• Molecular Ecology

Background:

• Accurate ecosystem monitoring is crucial for understanding environmental changes.
• Current methods like morphological analysis and metabarcoding have limitations in speed and accuracy for community composition.
• Environmental DNA (eDNA) metabarcoding offers high throughput but requires calibration for reliable species abundance estimation.

Purpose of the Study:

• To develop a quantitative approach for retrieving accurate living community assemblages from metabarcoding data.
• To address biases in metabarcoding by developing species-specific calibrations for large benthic foraminifera (LBF).
• To enable high-throughput, accurate monitoring of Indonesian coral reefs under anthropogenic pressure.

Main Methods:

• Calculated taxon-specific correction factors by comparing LBF surface area, biovolume, calcite volume, and mitochondrial gene copy numbers.
• Developed and validated a quantitative approach using mock samples and bulk reef sediment.
• Compared calibrated metabarcoding data with traditional morphological assessments.

Main Results:

• The calibration significantly improved the estimation of genus relative abundance, reducing error by approximately ±5%.
• The quantitative approach allows for reliable comparison between historical morphological datasets and future molecular datasets.
• Demonstrated the method's effectiveness in capturing fine-scale ecological dynamics, such as seasonal and pollution-driven changes.

Conclusions:

• The developed quantitative metabarcoding approach provides a validated, accurate, and high-throughput method for ecosystem monitoring.
• This method enhances the reliability of eDNA assessments for marine community composition.
• The approach supports effective reef monitoring operations by providing precise insights into ecological dynamics.