eDNA technology for monitoring terrestrial biodiversity: Technical highlights, challenges and progress

Biodiversity is a fundamental prerequisite for human survival, constituting an indispensable component of global ecosystems. The United Nations Sustainable Development Goal 15 (SDG 15) underscores the significance of conserving terrestrial biodiversity and strives to advance the sustainable utilization of terrestrial ecosystems. To achieve this goal, it is of the utmost importance to establish a comprehensive biodiversity monitoring system. As an emerging monitoring tool, environmental DNA (eDNA) metabarcoding technology offers a number of advantages, including species morphology-independent, rapidity, economical, and high accuracy. Consequently, it provides an effective method for monitoring terrestrial biodiversity. We outlined the key technical aspects of using eDNA metabarcoding as a tool for biodiversity monitoring in terrestrial ecosystems, discussed the challenges of using eDNA metabarcoding technology in biodiversity research, along with strategies for addressing these challenges, surveyed recent research advances regarding eDNA from different sources for terrestrial biodiversity monitoring, and proposed future research directions.