Applying fingerprinting methods on multielement measurements to track sediment transport in a small erosion-prone hilly catchment

To investigate particulate material dynamics,  48 soil, river bottom sediment, and river suspended particulate matter (SPM) samples were collected using a stratified sampling method in the Koppány River Basin, Hungary. Samples were analyzed via inductively coupled plasma mass spectrometry for the concentration of 44 elements, encompassing heavy metals, "light" metals, and rare earth elements. Multivariate statistical methods, particularly hierarchical cluster analysis and principal component analysis (PCA) were applied to identify patterns and drivers of material distribution across the catchment.

The PCA results revealed distinct partitioning of particulate material sources and transport behaviors. The first principal component (PC1) distinguished SPM samples from soil and sediment samples, underscoring the contrasting geochemical signatures of material mobilized during different flow conditions. The second principal component (PC2) separated SPM samples collected during low flow conditions from those collected during high flow conditions, reflecting hydrological influences on particulate transport and source contributions. Notably, spatial differences between the upper and lower parts of the catchment were found to be less significant than the temporal dynamics driven by flow conditions.

These preliminary findings highlight the pivotal role of hydrology in governing the geochemical composition of suspended materials and provide insights into sediment dynamics in hilly river basins. The study demonstrates the utility of multivariate approaches in disentangling complex interactions between geological and hydrological processes in catchment systems.