Submitted to: Soil and Tillage Research
Publication Type: Peer reviewed journal
Publication Acceptance Date: 7/4/2014
Publication Date: 7/15/2014
Publication URL: http://handle.nal.usda.gov/10113/59336
Citation: Gao, F., Feng, G.G., Sharratt, B.S., Zhang, M. 2014. Tillage and straw management affect PM10 emission potential in subarctic Alaska. Soil and Tillage Research. 144:1-7. Interpretive Summary: Tillage and residue management have the potential to minimize soil erosion and emission of fine particles in subarctic Alaska. Primary particle size distribution analysis revealed that tillage practices did not affect soil composition since the tillage treatments were located on uniform terrain. Aggregate size distribution analysis, however, indicated that no-till promoted aggregation of fine soil particles and resulted in the lowest freely-available PM10 and PM53 (soil particulates less than 10 and 53 um in diameter, irrespectively) content in the field as compared with other tillage treatments. Simulations with Single-event Wind Erosion Evaluation Program (SWEEP) also showed that PM10 emissions would be greater for conventional tillage, thus conservation practices play an important role in minimizing soil erosion and improving air quality in subarctic regions.
Technical Abstract: Emission of PM10 (particulates =10 um in diameter regulated by many nations as an air pollutant) from agricultural soils can impact regional air quality. Little information exists that describes the potential for PM10 and airborne dust emissions from subarctic soils or agricultural soils subject to different tillage and residue management. This study documents the influence of tillage and residue management on fine particulate emissions from a subarctic soil in interior Alaska. Surface characteristics and properties of a silt loam soil subject to conventional, spring disk, autumn chisel plow, and no tillage, with stubble and loose straw retained or removed from the soil surface after harvest of continuous barley (Hordeum vulgare L.), was measured twenty years after establishing treatments. These soil characteristics and properties were used to simulate PM10 emission potential and soil loss from tillage and residue treatments using the Single-event Wind Erosion Evaluation Program (SWEEP). Primary particle size analysis indicated no statistical difference in the size of primary soil particles among tillage or residue treatments. Aggregate size distribution analysis showed that tillage affected the freely-available PM10 content of the soil in the field. No tillage resulted in the lowest freely-available PM10 content as compared with other tillage treatments. Simulations made with SWEEP suggest that PM10 emissions and soil loss are potentially highest for conventional tillage and lowest for no tillage while emissions and soil loss were lower from spring disk than autumn chisel plow. Tillage practices can therefore affect air quality and long range transport of fine particulates emitted into the atmosphere during high wind events in subarctic Alaska.