Submitted to: Proceedings of the International Symposium on Wind Erosion
Publication Type: Proceedings
Publication Acceptance Date: June 4, 1997
Publication Date: N/A
Interpretive Summary: Scientists at the USDA-ARS Wind Erosion and Water Conservation Research Unit in Lubbock, Texas, in collaboration with Texas Tech Uiversity engineers, have developed a system to generate a controlled "dust storm" in a laboratory chamber. Instruments in this system can measure the amount and physical properties of dust produced from different materials by wind erosion. For soils of the Southern High Plains near Lubbock, sandy loams produced more dust than clay soils or sand, although the dust particles produced from sand were smaller in size. The surface of a dirt road was "dustier" than any of the agricultural soils.
Technical Abstract: Production and collection of fugitive dust in the laboratory, as opposed to the field, can provide improved control and more accurate measurement of the physical processes associated with airborne particulate matter. The USDA-ARS Wind Erosion and Water Conservation Research Unit in Lubbock, Texas, has developed a system to investigate the generation, particle size, and PM10 content of airborne dust. An aerosol generation chamber produces dust by controlled application of a specific amount of kinetic energy to a source sample. Instruments in the dust-transport and settling regions of the system measure the aerosol size spectra and the amount of PM10 evolved by different samples. We used this system to investigate the ability of different soils and road surfaces to produce dust, and to show how dust generation and production properties of a material change as a dust event progresses and soil aggregates break down. For soils of the Southern High Plains near Lubbock, Texas, sandy loams produced higher concentrations of PM10 than did clay soils or sand under the same experimental conditions, although PM10 as a fraction of all dust produced was highest for the sand. An unpaved road surface was more "dusty" in both categories than any of the soil types tested. Two fine sandy loam soils of different series produced distinctly different amounts of dust with different particle size characteristics, most likely due to variations in aggregate stability and parent materials.