Fish Biomonitoring and Ecological Assessment in the Dianchi Lake Basin Based on Environmental DNA

Fish are among the main target groups when conducting biomonitoring and ecological assessment of aquatic environments. Environmental DNA (eDNA) metabarcoding provides a unique opportunity to enhance throughput, precision, standardization. However, few fish monitoring studies based on eDNA have been conducted at basin scale. Taking Dianchi Lake three inflowing rivers (Panlong River, Baoxiang Chai River) as research objects, this study monitored diversity via metabarcoding, Index Biological Integrity (F-IBI) was constructed applied for environment. Here, we detected 41 species belonging 9 orders, 15 families, 35 genera in sampling areas, including 17 native such Hemiculter leucisculus, Cyprinus carpio, Silurus soldatovi. Distinct patterns were observed rivers. Particularly, Panlong River richer than that Lake, River. Water temperature (WT), chemical oxygen demand (COD), total nitrogen (TN), phosphorus (TP) significantly influenced distribution communities most sites (p < 0.05). Moreover, according F-IBI system, 25% defined ‘fine’ or above, 75% ‘impaired’ below. This provided insights into restoration precise management environment basin.