Data from: Multi-year deployment of a Single Frequency High-Frequency acoustic attenuation system for measuring fine suspended sediments in stream channels

<p dir="ltr">This is the dataset that was used to make the figures for the publication entitled "Multi-year deployment of a Single Frequency High-Frequency acoustic attenuation system for measuring fine suspended sediments in stream channels."</p><p dir="ltr"><u>How the dataset was generated</u>: A single frequency acoustic attention system was deployed for over three years in the Goodwin Creek Experimental Watershed in Panola County, MS, USA, to measure suspended fine sediments (d<63 microns) transported in the stream channel. The acoustic system utilized two 20-megahertz immersion transducers spaced 18 centimeters apart in a transmit-receive configuration. The transmit transducer produced sinusoidal waveforms with 15 pings per burst with a 0.25 millisecond ping delay and 0.5 second burst delay over 100 cycles. The system averaged 100 cycles per dataset, sampled at 60 megahertz, and converted the received signal amplitude to binary format before transferring it to a computer for storage and analysis. Physical samples from the site were collected and analyzed by USDA-ARS-NSL personnel to yield concentrations of sand (63 microns < d < 2000 microns) and fine (d<63 microns) particles in suspension. The physical samples of the water/sediment mixture were matched in time with the acoustic data to create a calibration fit based on the recorded signal relative to the water temperature corrected clear water signal. The relationship between the single frequency acoustic attention system data, physical pump samples, and concomitant measures of flow rate or stream depth were examined to evaluate and demonstrate the usefulness of the system. </p><p dir="ltr"><u>Why the dataset was generated</u>: This dataset presents an opportunity for employees at the USDA-ARS-National Sedimentation Laboratory (NSL) to utilize the single frequency acoustic attention system in order to enhance the array of measurements conducted within the Goodwin Creek Experimental Watershed. Continuous collection of sediment transport measurements is often unfeasible; therefore, sediment rating curves are employed to correlate a limited set of physical samples with ongoing measurements of stream discharge. Although this method is generally more precise than relying solely on sediment transport models, the relationships occurring among seasonal variations in watersheds, channel dynamics, and precipitation can lead to significant discrepancies between rating curves and actual transport rates. Furthermore, the data obtained from the Single Frequency Acoustic Attenuation System (SFAAS) may indicate clockwise hysteresis relationships between fine sediment transport and stream flow, aligning with anticipated patterns identified in prior studies. Additionally, the SFAAS has uncovered two distinct transport regimes that are not explained by temporal or seasonal climate variations, thereby opening avenues for future research focused on enhancing the hydrological understanding of how spatial rainfall heterogeneity influences sediment transport within the watershed.</p>

Tags: field-data-measurement, long-term-deployment, sediment, ultrasound
Organization: Department of Agriculture