A weight-of-evidence approach to integrate suspended sediment source information

Area of Science:

• Environmental Science
• Hydrology
• Geomorphology

Background:

• Identifying suspended sediment sources is crucial for effective water resource management.
• Traditional methods like monitoring, tracing, and modeling have limitations and uncertainties.
• Integrating multiple lines of evidence offers a more robust approach to source identification.

Purpose of the Study:

• To present and apply a Weight-of-Evidence (WoE) framework for integrating multiple lines of evidence to identify suspended sediment sources.
• To assess the effectiveness of the WoE approach in data-poor catchments.
• To highlight uncertainties and guide future research and monitoring efforts.

Main Methods:

• Utilized a Weight-of-Evidence (WoE) approach to integrate diverse data sources.
• Incorporated stream flow and suspended sediment monitoring data from river gauges.
• Employed geochemical sediment tracing at river junctions and catchment-scale sediment modeling (hillslope, gully, streambank, unsealed roads).

Main Results:

• The integrated WoE approach successfully identified some consistent major sediment sources across multiple evidence types.
• Inconsistencies among different lines of evidence revealed areas of high uncertainty in sediment source identification.
• The framework effectively maximized the use of scarce data in two Australian data-poor catchments.

Conclusions:

• The WoE framework enhances the integration of limited information for suspended sediment source identification.
• Explicitly considering uncertainties is vital for effective catchment management strategies.
• The approach effectively pinpoints areas requiring further monitoring and research for improved sediment management.