Integrating eDNA and Morphology Reveals Arsenic-Associated Assembly Processes of Benthic Invertebrates in Coral Reef Ecosystems

Research on the impacts of climate change and human activities on coral reef ecosystems has highlighted the need for more effective biodiversity assessment and conservation strategies. To address this, a team of scientists from the Chinese Academy of Sciences proposed an integrated framework combining environmental DNA (eDNA) metabarcoding and morphological identification to enhance the accuracy and scalability of biodiversity assessments in coral reef ecosystems. Their study, published in Environmental Research, demonstrates the complementary strengths of these two methods and reveals the pivotal role of arsenic in invertebrate community assembly.

Key Takeaways:

• The study demonstrates that metabarcoding detects only about half of invertebrate genera, while morphological methods show even greater taxonomic gaps, underscoring the complementary strengths of the two methods for comprehensive biodiversity monitoring.
• The integrated framework, which combines eDNA metabarcoding and morphological identification, provides a robust and scalable approach to detect ecological shifts, characterize biodiversity, and understand how environmental stressors-particularly heavy metal pollutants-shape invertebrate community dynamics in coral reef ecosystems.
• The study found a transition from stochastic to deterministic processes as arsenic heterogeneity increased, highlighting its pivotal role in invertebrate community assembly.
• The research has important implications for biodiversity monitoring, pollution assessment, and the conservation of fragile coral reef ecosystems under global environmental change.
• The study provides a valuable insight into the limitations of eDNA metabarcoding and the importance of integrating multiple methods for comprehensive biodiversity assessment.

Statistics:

• The researchers found that metabarcoding detects only about 50% of invertebrate genera, while morphological methods show even greater taxonomic gaps.
• The integrated framework was able to detect ecological shifts, characterize biodiversity, and understand how environmental stressors-shape invertebrate community dynamics in coral reef ecosystems.
• Heavy metal pollutants, particularly arsenic, were found to play a pivotal role in invertebrate community assembly.
• The study provides a valuable insight into the limitations of eDNA metabarcoding and the importance of integrating multiple methods for comprehensive biodiversity assessment.

Sources:

• Jiao Cheng et al. (2025), Integrating eDNA and morphology reveals arsenic-associated assembly processes of benthic invertebrates in coral reef ecosystems, Environmental Research, 285:122647.
• Chinese Academy of Sciences.
• Academic Press Inc Elsevier Science (www.elsevier.com; www.journals.elsevier.com/environmental-research/).