Remote Sensing of Suspended Sediment in Aquatic Systems

Remote sensing of suspended sediment employs satellite and airborne sensors to estimate the concentration and distribution of particulate matter in rivers, lakes, estuaries and coastal waters. By measuring water-leaving radiance across visible to near-infrared spectral bands, it is possible to derive empirical and semi-analytical relationships that link surface reflectance to suspended sediment concentration. Wide-area, frequent observation enables monitoring of sediment plumes, flood-driven pulses and seasonal cycles at spatial scales unattainable by in-situ sampling alone. Applications span deltaic wetland resilience, water quality management and sediment transport studies. Key challenges include correcting for atmospheric effects, avoiding sensor saturation in turbid waters and disentangling signals from coloured dissolved organic matter and phytoplankton. Advances in hyperspectral imaging, multi-sensor fusion and machine-learning inversion methods have improved accuracy and extended applicability from clear inland waters to highly turbid coastal zones. This work underpins management of reservoir sedimentation, assessments of erosion and deposition, and forecasts of ecosystem responses to land-use change and extreme weather.

Research from Nature Portfolio

Recent studies have documented sustained increases in suspended sediment concentration and the extent of sediment plumes across hundreds of global river deltas over the past two decades. Analysis of multi-sensor time series from 2000 to 2020 reveals that over half of the examined deltas exhibit rising sediment loads and plume areas despite regional variations in riverine supply. Variations are linked to tidal energy, wave climate, salinity gradients and delta morphology, highlighting the complex interplay of hydrodynamics and coastal geomorphology. The observed trends suggest potential resilience of deltaic wetlands to sea-level rise, although the persistence of this increase under future climatic and anthropogenic pressures remains uncertain.

Remote Sensing of Suspended Sediment in Aquatic Systems publication trend

The graph below shows the total number of articles in remote sensing of suspended sediment in aquatic systems across all publications each year (not limited to Nature Index journals).

Technical terms

Suspended Sediment Concentration (SSC): Mass of particulate matter per unit volume of water derived from remotely sensed reflectance.

Total Suspended Solids (TSS): Gravimetric measurement of suspended particles in water often used interchangeably with SSC in remote sensing contexts.

Atmospheric Correction (AC): Process to remove scattering and absorption effects of atmosphere from satellite imagery to retrieve true water reflectance.

Ocean Colour: Spectral signature of water bodies in visible to near-infrared wavelengths used to infer constituent concentrations.

Hyperspectral Resolution: Fine spectral sampling that enables discrimination of subtle variations in water constituent signatures.

References

1. Sustained increase in suspended sediments near global river deltas over the past two decades. Nature Communications (2024).
2. Optimizing Satellite Mission Requirements to Measure Total Suspended Solids in Rivers. IEEE Transactions on Geoscience and Remote Sensing (2023).
3. Retrieval of suspended sediment concentration (SSC) in the Arabian Gulf water of arid region by Sentinel-2 data. The Science of The Total Environment (2023).
4. Atmospheric Corrections and Multi-Conditional Algorithm for Multi-Sensor Remote Sensing of Suspended Particulate Matter in Low-to-High Turbidity Levels Coastal Waters. Remote Sensing (2017).