Comparison of eDNA with conventional infauna sampling when assessing pollution impacts

Area of Science:

• Marine ecology
• Environmental science
• Molecular biology

Background:

• Environmental DNA (eDNA) methods are emerging for marine ecosystem monitoring.
• Validation against traditional methods like macrobenthos sampling is crucial for assessing marine pollution.
• Benthic assemblages are key indicators of marine pollutant impacts.

Purpose of the Study:

• To compare the sensitivity of eDNA metabarcoding assays (16S rRNA, 18S rRNA, COI) with traditional macrobenthos sampling.
• To evaluate the effectiveness of these methods in detecting marine pollutant impacts.
• To assess the performance of eDNA and macrobenthos in response to different pollutant types.

Main Methods:

• Sampling of environmental and pollutant parameters in southeastern Australia.
• Application of three eDNA metabarcoding assays (16S rRNA, 18S rRNA, mitochondrial COI).
• Traditional macrobenthos sampling using a van Veen grab.

Main Results:

• Both eDNA metabarcoding and macrobenthos sampling detected pollutant-associated impacts.
• eDNA metabarcoding showed higher sensitivity to heavy metal pollutants.
• Macrobenthos sampling was more responsive to organic pollutants.

Conclusions:

• eDNA metabarcoding and macrobenthos sampling are both valuable tools for detecting marine pollution impacts.
• Each method exhibits distinct sensitivities to different pollutant types, suggesting complementary roles in monitoring.
• Further research can refine eDNA approaches for comprehensive marine pollution assessment.