Monitoring Animal Diversity along the Qinling Power Transmission Project Using iDNA and eDNA

Considering limited coverage range and low efficiency of traditional wildlife monitoring methods in the biodiversity impact assessment of long-distance power transmission projects, the purpose of this study was to explore the monitoring capacity of environmental DNA (eDNA) and insect-derived DNA(iDNA) to terrestrial wildlife surveillance in the complex mountainous environment of the Qinling Mountains.In this study, the Baoji-Hanzhong 750 kV transmission line along the Qinling Mountains was selected as the research area.Infrared cameras were deployed at 15 sampling sites, and air and fly samples were collected at the same sites. After extracting DNA from air and fly samples, PCR amplification was performed using vertebrate specific primers 12SV05, and species identification was performed using high-throughput sequencing technology.The species detection probability, the monitoring effect of animal communities and the influencing factors of the three monitoring methods were compared by using the methods of diversity index, principal coordinate sorting, species accumulation curve and model-based species occupancy.The results showed that 21 species of terrestrial vertebrates were recorded by infrared cameras, and 76 species were monitored by eDNA and iDNA,covering mammals, birds, amphibians and reptiles and including 17 species of national key protected wild animals.The three methods were different in species detection: infrared camera had more advantages for medium and large mammals; eDNA showed higher sensitivity to small birds and nocturnal birds; iDNA was particularly effective in small mammals.The results indicated that eDNA and iDNA technology had the advantages of more convenient sampling method, larger investigation area and more kinds of monitoring animals,especially in the monitoring of small animals, hidden species and rare species.The integration of traditional wildlife monitoring methods and environmental DNA approaches can substantially enhance the comprehensiveness and accuracy of wildlife diversity assessment. This method combination offers a scientific, efficient, and convenient technical solution for the long-term monitoring, assessment, and protection management of ecological and environmental impacts during the planning, construction, and operation of power transmission projects or similar long-distance linear projects.