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Watershed Planning within a Quantitative Scenario Analysis Framework
Published on: July 24, 2016
Improving freshwater ecosystem assessment via the integration of eDNA-based multitrophic biotic groups
Minglei Ren1, Xue Gong2, Mengdie Geng1
1State Key Laboratory of Lake and Watershed Science for Water Security, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing, 211135, China.
Water Research
|July 28, 2026
Summary
A new multitrophic index of biotic integrity (IBI_m) using environmental DNA (eDNA) effectively assesses freshwater health by integrating multiple biological groups. This approach provides a more sensitive and comprehensive evaluation of ecosystem degradation than traditional methods.
Area of Science:
- Ecology
- Environmental Science
- Molecular Biology
Background:
- Freshwater ecosystems face degradation and biodiversity loss, necessitating improved ecological health assessment.
- Traditional methods using single taxonomic groups are limited due to taxon-specific responses and temporal lags in detecting degradation.
- Robust frameworks are needed to capture complex ecosystem changes.
Purpose of the Study:
- To develop and validate a multitrophic index of biotic integrity (IBI_m) for assessing freshwater ecological health.
- To integrate diverse biological data (bacteria, fungi, algae, invertebrates) using environmental DNA (eDNA) metabarcoding.
- To compare the effectiveness of IBI_m with traditional single-taxon indices and water quality indices (WQI).
Main Methods:
- Utilized environmental DNA (eDNA) metabarcoding to analyze bacteria, fungi, eukaryotic algae, and invertebrates.
- Developed a multitrophic index of biotic integrity (IBI_m) integrating data from these multiple biological groups.
- Applied the IBI_m to assess ecological health in 40 shallow lakes in the Yangtze-Huaihe River basin, China.
Main Results:
- The IBI_m demonstrated strong associations with environmental gradients and sensitivity to declines in beta-diversity.
- IBI_m showed stronger correlations with physicochemical variables (e.g., dissolved oxygen, ammonia) than single-taxon indices.
- Lower IBI_m values indicated reduced local contributions to beta diversity (LCBD), signifying a loss of community uniqueness.
- IBI_m assessments were more stringent than WQI, with only 37.5% of lakes classified as 'Good' compared to 82.5% by WQI.
Conclusions:
- The multitrophic index of biotic integrity (IBI_m) offers a more comprehensive and sensitive approach to freshwater ecological health assessment.
- IBI_m effectively integrates diverse biological data, providing deeper insights into ecosystem degradation.
- This framework enhances biomonitoring and management strategies for freshwater ecosystems facing global change.
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