A Radio Frequency Identification System for Monitoring Coarse Sediment Particle Displacement

A radio frequency identification system was implemented to monitor the displacement of coarse particlesfollowing runoff in two upland, ephemeral channels on the USDA-ARS Walnut Gulch Experimental Watershed insoutheastern Arizona. Commercially available radio frequency identification components including transponders, anantenna, a reader, and software were used to develop a system for locating particles under field conditions. During the 2003field season, 124 particles were located following four runoff events in two ephemeral channels. The locations of 340 particlepositions were measured with a real-time kinematic geopositioning system after each particle was located with the radiofrequency identification system. The overall recovery rate was 96%. The passive transponder system offers the advantagesof low cost, consistent results under harsh environmental conditions, and no need for a power supply in the particle. The radiofrequency identification system can be used to efficiently collect data for developing sediment transport equations andimproving mathematical models for simulating sediment transport under natural runoff conditions.