Employing novel wireless agricultural sensors for real-time monitoring of fluvial bank erosion

Bank erosion impacts sediment transport and river morphology, both important processes for river managers. Some important factors, such as timing and causes of bank erosion, are difficult to assess with established techniques. We explore the capability of smart sensors, actually developed for the agricultural sector, to measure soil moisture and temperature as well as movement in real time on banks of northern rivers in different geographical, climatological and landscape settings. Soil movement and its timing were easy to identify from the measurements, and in many cases, the reason for the onset of movement could be inferred. The sensors automatically upload data with a high temporal resolution for a long period of time, while only minimally disturbing the bank itself. However, the sensor approach has a low spatial resolution (point measurements), and therefore, complementing the measurements with approaches with a high spatial resolution, such as spatially continuous digital elevation models of differencing techniques or seismic sensors, is advised. Overall, the measurement approach using new agricultural sensors has several unique advantages and disadvantages and can be a good tool for the monitoring of river bank erosion and could lead to new insights.