Progress 10/25/10 to 10/24/15

Outputs
Progress Report Objectives (from AD-416): 1) Improve and extend the Wind Erosion Prediction System (WEPS) model and 2) integrate WEPS with the National Soil Erosion Research Lab (NSERL) Water Erosion Prediction Program (WEPP) model to consolidate research resources for the two models and to improve the ease of simulating both wind and water erosion. Approach (from AD-416): 1. a) Extend WEPS beyond the current homogenous simulation area approach to improve simulation of field-scale variability by: i) further modularizing the erosion science code, ii) adding sub-field capability, iii) refining WEPS gridding algorithms, and iv) adding landscape terrain effects to WEPS; b) improve model inputs and science for WEPS through: i) updating weather, ii) adding crop competition and improved crop growth, iii) adding seasonal wind barrier porosity variability, and iv) improving soil and vegetation measurements with laser distance techniques; c) extend WEPS to additional soil types (i.e., organic dominated soils) and treatments (i.e., applied biosolids); and d) modify WEPS for application to special problems (i.e., regional air quality modeling, add PM2.5 emission, batch mode for WEPS, develop a single-event model); and e) publish the WEPS technical document. 2. Utilize common science and interface code for WEPP and WEPS to: a) provide common runoff and evaporation processes between the two models; b) provide common �winter processes� (simulation of freezing, thawing, freeze-drying processes); c) add water erosion specific input (hillslope length, slope, etc.) and output (water erosion, runoff, etc.) to the current standalone WEPS interface; d) address restrictions to simulating a homogeneous region represented by a single soil with common management practices applied to the entire field; and e) provide the necessary inputs to represent water erosion specific practices, such as terraces, artificial drainage, etc. to the user interface. The Wind Erosion Prediction System (WEPS) model was officially released to the Natural Resources Conservation Service (NRCS) in October 2010 and subsequently installed on 15,000 NRCS computers including 2,200 field offices nationwide. NRCS is using WEPS to: a) assist land managers in controlling wind erosion; b) establish acceptable field level conservation plans; and c) determine wind erosion susceptibility as part of the Conservation Reserve Program (CRP) and other national conservation programs. The USDA considers WEPS a critical component of the strategy to reduce particulate emissions from cultivated agricultural lands. Updates of WEPS were provided to NRCS in October 2011 and September 2013. The 2011 update included an improved weather generator and database. The 2013 update included: i) correction of errors in the hydrology and residue decomposition code, a bug fix in erosion reporting, and other minor bugs; ii) changed interface to allow WEPS to run under Java 7 and fixed interface bugs and made enhancements related to input/output reporting and printing, and selection of barriers; and iii) updated crops, operations, and weather databases. Additional improvements were made to the WEPS interface in 2014 for a future release that includes improved graphical plotting, general maintenance of the model code, and minor bug fixes reported by NRCS. ARS scientists continued to improve the WEPS model through development of more maintainable computer code that allows expansion to more complex field configurations and regional simulations. Plant growth routines were developed and tested for multiple crops within a field to simulate situations such as double cropping and weed competition. WEPS was also modified for use as part of a dust warning system as well as regional dispersion of particulate emissions from soil. Laboratory wind tunnel studies were conducted on 15 soils from 5 states and equations developed to predict the emission of fine dust particles less than 2.5 microns in size which are regulated by the US Environmental Protection Agency as a health concern. This research will aid in environmental assessments and the design of control practices. The studies also compared emissions under conventional tillage and no-till managements and found no significant difference in fine dust emissions between the two tillage systems. Collaborative field research was conducted to understand the wind erodibility of organic matter dominated soils (20-80% organic matter). Field wind tunnel tests were completed by ARS scientists from Ft Collins, CO (formerly Manhattan, KS) and Lubbock, TX in Florida and Michigan to investigate the wind erodibility of highly productive but highly erodible organic matter dominated soils and equations developed to predict soil loss. Collaborative field studies by an ARS scientist from Ft Collins, CO and University scientists in Florida and Michigan were also conducted to determine the effects of organic dominated soil properties, climate, and management on soil wind erodibility properties over time. Field sites were sampled for two years, analysis performed and results are being evaluated. A laboratory rainfall simulation and wind tunnel study is on- going using a trough type rainfall simulator to study the effects of rainfall and subsurface wetting on crust formation and subsequent wind erodibility of soils dominated by organic matter. Collaborative research between ARS, Ft Collins, CO and a graduate student from Kansas State University studied the effects of crop residue removal for bioenergy on wind erosion potential. Field wind erodibility measurements were made at nine locations in Kansas. Results consistently showed that complete crop residue removal increased soil wind erodible fraction (<0.84 mm in diameter) while overall soil aggregate size and surface roughness decreased, indicating that complete residue removal increases risks of wind erosion. The WEPS model was also used to simulate the effects of crop residue removal for bioenergy on wind erosion potential. Simulations were made for over 90 crop rotations on the major soil types in 241 counties in five Great Plains states (CO, KS, OK, NE, and TX). Rotations were simulated for high and low yields crops, with and without residue removal. Analyses indicate variation in soil erosion and soil organic matter trends as a function of crop type, rotation, and field management practices across different soil types within a single county and at the regional level. Considerable variation in removable residue amounts also occurred across different rotations, especially with respect to crop type, rotation, soil type, and tillage. Results obtained in this study will help advance the overall knowledge base of both public and private- focused commodity and bioenergy crop production agriculture by providing small resolution (i.e., soil type) data on soil erosion and health trends that could have a pronounced effect on producer economics and long-term land sustainability. Field studies were completed to evaluate seasonal changes in barrier porosity on wind speed. Wind speed reductions were measured under varying leaf porosity as leaves dropped in the fall. In addition, a dust generator was used to determine the removal efficiency for fine particulates in an Osage Orange windbreak. Equations were developed to predict wind speed changes in the WEPS model. All chapters of the WEPS Technical Documentation (except for the Erosion submodel which is currently being updated) have been updated and formatted for publishing as a USDA Handbook in 2016. A Department of Defense funded field research project to investigate the effects of military training vehicle activity on the wind erodibility of the land was completed. The studies were conducted at four military sites: Fort Riley, KS, Fort Benning, GA, Yakima Training Center, WA, and White Sands Missile Range, NM. An understanding of the effects of such activities will aid the military to better manage training lands. All laboratory analysis of the field data collected to date has been completed for the four sites and the collation of that data is in progress for the final report. Accomplishments 01 Wind erosion model predicts less soil loss under climate change in the Pacific Northwest. Climate change may impact soil health and productivity as a result of accelerated or decelerated rates of erosion. ARS researchers in Pullman, WA and Fort Collins, CO used the Wind Erosion Prediction System (WEPS) to assess wind erosion in winter wheat- summer fallow and winter wheat-camelina-summer fallow rotations under a future climate projected by 18 Global Climate Models for a conservative CO2 emissions pathway. A significant increase in temperature and nominal increases in precipitation were projected by an ensemble of climate models for the ColumbiaPlateaubythemid-21st century. Soil losses were 25�84% lower for a mid-21st century climate, due in part to greater biomass production associated with CO2 fertilization and warmer temperatures. The reduction in soil loss was projected to be more apparent for conservation tillage practices in the future. These results are useful for farmers and action agencies. 02 Wind reduction of tree windbreaks varies with leaf presence. The effectiveness of tree wind breaks varies with seasonal changes to porosity as leaves are present in spring and summer and absent in fall and winter. ARS researchers at Fort Collins, CO and Manhattan, KS completed field studies that evaluated effects of seasonal changes in wind barrier porosity on wind speed reduction. Wind velocity reductions were greater for the leaf-on condition than for the leaf-off condition and ranged from 40-80% downwind of the leaf-on barrier compared to 20-38% for the leaf-off condition. Equations were developed to predict wind speed changes in the WEPS model. The modified model will be provided to NRCS for improved conservation planning on agricultural fields where windbreaks are present.

Impacts
(N/A)

Publications

• Retta, A., Wagner, L.E., Tatarko, J. 2014. Military vehicle trafficking impacts vegetation and soil bulk density at Fort Benning, Georgia. Transactions of the ASABE. 57(4):1043-1055. DOI:
• McMaster, G.S., Ascough II, J.C., Edmunds, D.A., Wagner, L.E., Fox, F.A., Dejonge, K.C., Hansen, N.C. 2014. Simulating unstressed crop development and growth using the Unified Plant Growth Model (UPGM). Environmental Modeling and Assessment. 19(5):407-424. DOI:10.1007/s10666-014-9402-x.
• Nelson, R., Tatarko, J., Ascough II, J.C. 2015. Soil erosion and organic matter variations for central Great Plains cropping systems under residue removal. Transactions of the ASABE. 58(2):415-427. DOI:10.13031/trans.58. 10981.
• Meeks, J.C., Wagner, L.E., Maghirang, R.G., Tatarko, J. 2015. Fugitive dust emissions from off-road vehicle maneuvers on military training lands. Transactions of the ASABE. 58(1):49-60. DOI:
• Sharratt, B.S., Tatarko, J., Abatzoglou, J., Fox, F.A., Huggins, D.R. 2015. Implications of climate change on wind erosion of agricultural lands in the Columbia Plateau. Weather and Climate Extremes. 10:10-16.

Progress 10/01/13 to 09/30/14

Outputs
Progress Report Objectives (from AD-416): 1) Improve and extend the Wind Erosion Prediction System (WEPS) model and 2) integrate WEPS with the National Soil Erosion Research Lab (NSERL) Water Erosion Prediction Program (WEPP) model to consolidate research resources for the two models and to improve the ease of simulating both wind and water erosion. Approach (from AD-416): 1. a) Extend WEPS beyond the current homogenous simulation area approach to improve simulation of field-scale variability by: i) further modularizing the erosion science code, ii) adding sub-field capability, iii) refining WEPS gridding algorithms, and iv) adding landscape terrain effects to WEPS; b) improve model inputs and science for WEPS through: i) updating weather, ii) adding crop competition and improved crop growth, iii) adding seasonal wind barrier porosity variability, and iv) improving soil and vegetation measurements with laser distance techniques; c) extend WEPS to additional soil types (i.e., organic dominated soils) and treatments (i.e., applied biosolids); and d) modify WEPS for application to special problems (i.e., regional air quality modeling, add PM2.5 emission, batch mode for WEPS, develop a single-event model); and e) publish the WEPS technical document. 2. Utilize common science and interface code for WEPP and WEPS to: a) provide common runoff and evaporation processes between the two models; b) provide common �winter processes� (simulation of freezing, thawing, freeze-drying processes); c) add water erosion specific input (hillslope length, slope, etc.) and output (water erosion, runoff, etc.) to the current standalone WEPS interface; d) address restrictions to simulating a homogeneous region represented by a single soil with common management practices applied to the entire field; and e) provide the necessary inputs to represent water erosion specific practices, such as terraces, artificial drainage, etc. to the user interface. Under Objective 1, a new release of the Wind Erosion Prediction System (WEPS) was delivered to NRCS. The updated model included several improvements: i) correction of computer code in the hydrology and residue decomposition routines, a bug fix in erosion reporting, and other minor bugs; ii) updated interface to allow WEPS to run under Java 7, fixed interface bugs, added crop-soil-water balance improvements related to reporting and printing, and improved the selection method for barriers; iii) updated databases with improved crops, operations, and weather data as well as revisions to selected wind data. Additional improvements were made to the WEPS interface for a future release to NRCS and the general public that includes: i) addition of improved graphical plotting; and ii) general maintenance of the model code and fixing of minor bugs reported by NRCS. Laboratory wind tunnel studies were conducted on 15 cultivated soils from 5 states with a goal of predicting the emission of fine dust particles less than 2.5 microns in size. These fine particles are regulated by the US Environmental Protection Agency as a health concern and predicting the potential amounts of emissions from various soils will aid in environmental assessments and the design of control practices. The studies investigated loose emissions as well as abrasion emissions. Equations to predict the emission of fine dust were developed. The studies also compared emissions under conventional tillage with no-till managements and found no significant difference in fine dust emissions between the two tillage systems. Field studies were conducted to evaluate seasonal changes in barrier porosity on wind speed. Two mobile anemometer towers were placed upwind and downwind of a tree wind break. The downwind tower was placed 1x, 2x, 4x, 7x, and 10x the average height of the barrier. Wind speed reductions were measured under varying leaf porosity as leaves dropped in the fall. Equations are under development to predict wind speed changes in the Wind Erosion Prediction System (WEPS) model. A laboratory rainfall simulation study is being initiated. A trough type rainfall simulator is being set up and calibrated to study the effects of rainfall and subsurface wetting on crust formation and subsequent wind erodibility of soils dominated by organic matter (>20%). Such soils are important agricultural soils in some parts of the country, including Florida and Michigan, and are highly erodible by wind. A field research project was completed at the White Sands Missile Range in January on two soil types. This study is part of a larger project to investigate the effects of military training vehicle activity on the wind erodibility of the land. An understanding of the effects of such activities will aid the military to better manage training lands. All laboratory analysis of the field data collected to date has been completed for four sites and the collation of that data is in progress for the final report. Accomplishments 01 Simulations of crop residue removal for bioenergy show effects on wind erosion potential and changes in soil organic carbon (SOC). The diversity of land use and potential crop residues for biofuels within the United States Central Great Plains requires sustainable production for maintaining or enhancing local soil and environmental quality. ARS and private researchers at Manhattan, KS and Ft. Collins, CO made approximately 600,000 simulations using the Wind Erosion Prediction System (WEPS) model for over 90 crop rotations on all soil types in 241 counties in five Great Plains states (CO, KS, OK, NE, TX) and estimated erosion loss as well as changes in SOC. Rotations were simulated for high and low crop yields, with and without residue removal, as well as for reduced and no-till managements. Rotations with low-residue crops (e.g., canola and cotton) had soil erosion greater than the 5 ton/acre/ yr NRCS tolerable loss limit (T) and decreasing SOC, whereas crops grown in continuous rotation (i.e., corn and, to a lesser extent, winter wheat) exhibited soil erosion less than T. The simulations also show that corn and sorghum stover, as well as winter wheat straw, could potentially be removed in select regions of the study area while maintaining soil erosion limits below the tolerable loss limit T and have positive SOC trends. Results will help producers and planners determine the amounts of crop residue available for bioenergy purposes while maintaining soil and air quality in the study regions.

Impacts
(N/A)

Publications

• Blanco-Canqui, H., Ferguson, R.B., Jin, V.L., Schmer, M.R., Wienhold, B.J., Tatarko, J. 2014. Can cover crop and manure maintain or improve soil properties after stover removal from irrigated no-till corn? Soil Science Society of America Journal. 78:1368-1377. DOI: 10.2136/SSSAJ2013.12.0550.

Progress 10/01/12 to 09/30/13

Outputs
Progress Report Objectives (from AD-416): 1) Improve and extend the Wind Erosion Prediction System (WEPS) model and 2) integrate WEPS with the National Soil Erosion Research Lab (NSERL) Water Erosion Prediction Program (WEPP) model to consolidate research resources for the two models and to improve the ease of simulating both wind and water erosion. Approach (from AD-416): 1. a) Extend WEPS beyond the current homogenous simulation area approach to improve simulation of field-scale variability by: i) further modularizing the erosion science code, ii) adding sub-field capability, iii) refining WEPS gridding algorithms, and iv) adding landscape terrain effects to WEPS; b) improve model inputs and science for WEPS through: i) updating weather, ii) adding crop competition and improved crop growth, iii) adding seasonal wind barrier porosity variability, and iv) improving soil and vegetation measurements with laser distance techniques; c) extend WEPS to additional soil types (i.e., organic dominated soils) and treatments (i.e., applied biosolids); and d) modify WEPS for application to special problems (i.e., regional air quality modeling, add PM2.5 emission, batch mode for WEPS, develop a single-event model); and e) publish the WEPS technical document. 2. Utilize common science and interface code for WEPP and WEPS to: a) provide common runoff and evaporation processes between the two models; b) provide common �winter processes� (simulation of freezing, thawing, freeze-drying processes); c) add water erosion specific input (hillslope length, slope, etc.) and output (water erosion, runoff, etc.) to the current standalone WEPS interface; d) address restrictions to simulating a homogeneous region represented by a single soil with common management practices applied to the entire field; and e) provide the necessary inputs to represent water erosion specific practices, such as terraces, artificial drainage, etc. to the user interface. A new release of the Wind Erosion Prediction System to NRCS is planned for September, 2013. The updated version will include the following improvements: i) correction of errors in the hydrology and residue decomposition code, a bug fix in erosion reporting, and other minor bugs; ii) changed interface to allow WEPS to run under Java 7 and fixed interface bugs or made other enhancements related to input/output reporting and printing, and selection of barriers; iii) updated databases with improved crops, operations, and weather records. The Wind Erosion Prediction System computer code was also enhanced with the addition of sub-field capability. The model can now simulate field variation in soil type and management actions within a field and between adjacent fields. Once testing is complete, the user interface and documentation will be revised and the enhanced model made available to the public. The core component of the model that simulates the wind erosion processes has also been coded into discrete modules. The use of improved computer memory allocation and a modular structure enable developers to more easily add new functions, such as wind blowing and movement of surface residues. These enhancements will be included in a future release. Collaborative research with university scientists in Florida and Michigan continued a study with the goal to determine the effects of organic dominated soil properties, climate, and management on soil wind erodibility properties over time. The field portion of the research was completed and data analysis is in progress. Laboratory wind tunnel research was begun into predicting the emission of fine particles less than 2.5 microns in size from agricultural soils. Such fine particles are regulated by the US Environmental Protection Agency as a health concern and predicting the potential amounts of emissions from various soils will aid in the design of control practices. With the aid of satellite data, the erosion submodel has been incorporated into a regional air quality modeling system. This new modeling system can be applied to investigate the impact of windblown dust on ambient PM10 concentrations for historical events. The Wind Erosion Prediction System model was used to simulate the effects of crop residue removal for bioenergy on wind erosion potential. Results will help producers and planners determine the amounts of crop residue available for bioenergy purposes while maintaining the soil and air quality in the regions where residue is removed. Simulations were made for over 90 crop rotations on the major soil types in 241 counties in five Great Plains states (CO, KS, OK, NE, TX). Rotations were simulated for high and low yields crops, with and without residue removal. Three chapters were substantially completed for an upcoming USDA Agricultural Handbook: The Wind Erosion Prediction System Technical Documentation. The chapters were: 1) Hydrology Submodel; 2) Data Requirements; 3) Single Storm Applications.

Impacts
(N/A)

Publications

• Evers, B.J., Blanco-Canqui, H., Staggenborg, S., Tatarko, J. 2013. Dedicated bioenergy crop impacts on soil wind erodibility and organic carbon in Kansas. Agronomy Journal. 105(5):1271-1276.
• Gao, J., Wagner, L.E., Fox, F.A., Chung, S., Vaughn, J., Lamb, B.K. 2013. Spatial application of WEPS for estimating wind erosion in the Pacific Northwest. Transactions of the ASABE. 56(2):613-624.
• Wagner, L.E., Fox, F.A. 2013. The management submodel of the Wind Erosion Prediction System. Applied Engineering in Agriculture. 29(3):361-372.
• Tatarko, J., Sporcic, M.A., Skidmore, E.L. 2013. A history of wind erosion prediction models in the United States Department of Agriculture Prior to the Wind Erosion Prediction System. Aeolian Research. 10:3-8.
• Chung, S.H., Herron-Thorpe, F.L., Lamb, B.K., Vanreken, T.M., Vaughn, J., Gao, J., Wagner, L.E., Fox, F.A. 2013. Application of the Wind Erosion Prediction System in the AIRPACT regional air quality modeling framework. Transactions of the ASABE. 56(2):625-641.
• Retta, A., Wagner, L.E., Tatarko, J., Todd, T. 2013. Evaluation of bulk density and vegetation as affected by military vehicle traffic at Fort Riley, Kansas. Transactions of the ASABE. 56(2):653-665.
• Blanco-Canqui, H., Holman, J.D., Schlegel, A.J., Tatarko, J., Shaver, T.M. 2013. Replacing fallow with cover crops in a semiarid soil: effects on soil properties. Soil Science Society of America Journal. 77(3):1026-1034.
• Hagen, L.J., Casada, M.E. 2013. Effect of canopy leaf distribution on sand transport and abrasion energy. Aeolian Research. 10:37-42.
• Wagner, L.E. 2013. A history of wind erosion prediction models in the United States Department of Agriculture: The Wind Erosion Prediction System (WEPS). Aeolian Research. 10:9-24.
• Zobeck, T.M., Baddock, M., Van Pelt, R.S., Tatarko, J., Acosta Martinez, V. 2013. Soil property effects on wind erosion of organic soils. Aeolian Research. 10(1):43-51.

Progress 10/01/11 to 09/30/12

Outputs
Progress Report Objectives (from AD-416): 1) Improve and extend the Wind Erosion Prediction System (WEPS) model and 2) integrate WEPS with the National Soil Erosion Research Lab (NSERL) Water Erosion Prediction Program (WEPP) model to consolidate research resources for the two models and to improve the ease of simulating both wind and water erosion. Approach (from AD-416): 1. a) Extend WEPS beyond the current homogenous simulation area approach to improve simulation of field-scale variability by: i) further modularizing the erosion science code, ii) adding sub-field capability, iii) refining WEPS gridding algorithms, and iv) adding landscape terrain effects to WEPS; b) improve model inputs and science for WEPS through: i) updating weather, ii) adding crop competition and improved crop growth, iii) adding seasonal wind barrier porosity variability, and iv) improving soil and vegetation measurements with laser distance techniques; c) extend WEPS to additional soil types (i.e., organic dominated soils) and treatments (i.e., applied biosolids); and d) modify WEPS for application to special problems (i.e., regional air quality modeling, add PM2.5 emission, batch mode for WEPS, develop a single-event model); and e) publish the WEPS technical document. 2. Utilize common science and interface code for WEPP and WEPS to: a) provide common runoff and evaporation processes between the two models; b) provide common �winter processes� (simulation of freezing, thawing, freeze-drying processes); c) add water erosion specific input (hillslope length, slope, etc.) and output (water erosion, runoff, etc.) to the current standalone WEPS interface; d) address restrictions to simulating a homogeneous region represented by a single soil with common management practices applied to the entire field; and e) provide the necessary inputs to represent water erosion specific practices, such as terraces, artificial drainage, etc. to the user interface. The Wind Erosion Prediction System (WEPS) model is a critical component of the USDA strategy to reduce particulate emissions from cultivated agricultural lands. An update release of WEPS (version 1.2.9) was provided to NRCS in October 2011 and an updated database in July 2012. ARS scientists at Manhattan, KS continue to improve the WEPS model and provide technical support including more maintainable computer code allowing expansion to complex fields and regional simulations. An improved weather generator was developed and will be incorporated into WEPS. WEPS has been modified for use as part of a dust warning system and two manuscripts have been submitted for publication on using WEPS to predict regional dispersion of soil particulate emissions. Collaborative field research by an ARS scientist from Manhattan, KS and University scientists in Florida and Michigan was initiated to determine the effects of organic dominated soil properties, climate, and management on soil wind erodibility properties over time. Field sites were sampled and analysis performed for the first year of the two year study. Collaborative research between ARS, Manhattan, KS and graduate students from Kansas State University studied the effects of crop residue removal for bioenergy on wind erosion potential. Field wind erodibility measurements were made at nine locations in Kansas. After entering the field measurements into WEPS, the potential effects on wind erosion of plant residue removal for bio-energy will be determined. Three chapters were completed for an upcoming USDA Agricultural Handbook: WEPS Technical Documentation. In addition, six publications related to this project were submitted to peer-reviewed journals. Reviews of methodologies available for vegetative barrier assessment showed that conventional methods like photogrammetry are low-cost but they provide a less accurate assessment of tree porosity and are limited to two-dimensional representations of vegetative barriers. Laser-based protocols for determining tree porosities are beneficial in terms of providing complex parameters (especially three-dimensional representations) that are never achievable using conventional methods but are limited by equipment cost and training. Numerical simulations of barrier effects have been initiated and will be validated using field test results for determining optimal barrier characteristics. Accomplishments 01 Wind tunnel measurements of abrasion energy. Growing plants help contro wind erosion by reducing the wind speed at the soil surface and by trapping a portion of the eroding soil particles. However, few data exis on the effects of plant height and density on wind erosion. ARS researchers in Manhattan, KS used a wind tunnel study to determine the abrasion energies experienced by standing wheat plants (simulated with split plastic straws). Shorter plants (~6 inches) deflected particles upward so that more abrasion energy was experienced higher on the plants compared to taller plants (~9 inches) where there was a steady decrease abrasion energy further up on the plants. Also, taller plants and highe plant densities reduced wind speeds at the soil surface and thus reduced the amount of soil that can be dislodged to cause abrasion. These result provide essential information for conservation planners and wind erosion researchers to design optimal conservation systems with the most appropriate plant population densities for erosion control for expected wind speeds.

Impacts
(N/A)

Publications

• Boac, J.M., Casada, M., Maghirang, R.G., Harner, III, J.P. 2012. 3-D and quasi-2-D discrete element modeling of grain commingling in a bucket elevator boot system. Transactions of the ASABE. 55(2):659-672.

Progress 10/01/10 to 09/30/11

Outputs
Progress Report Objectives (from AD-416) 1) Improve and extend the Wind Erosion Prediction System (WEPS) model and 2) integrate WEPS with the National Soil Erosion Research Lab (NSERL) Water Erosion Prediction Program (WEPP) model to consolidate research resources for the two models and to improve the ease of simulating both wind and water erosion. Approach (from AD-416) 1. a) Extend WEPS beyond the current homogenous simulation area approach to improve simulation of field-scale variability by: i) further modularizing the erosion science code, ii) adding sub-field capability, iii) refining WEPS gridding algorithms, and iv) adding landscape terrain effects to WEPS; b) improve model inputs and science for WEPS through: i) updating weather, ii) adding crop competition and improved crop growth, iii) adding seasonal wind barrier porosity variability, and iv) improving soil and vegetation measurements with laser distance techniques; c) extend WEPS to additional soil types (i.e., organic dominated soils) and treatments (i.e., applied biosolids); and d) modify WEPS for application to special problems (i.e., regional air quality modeling, add PM2.5 emission, batch mode for WEPS, develop a single-event model); and e) publish the WEPS technical document. 2. Utilize common science and interface code for WEPP and WEPS to: a) provide common runoff and evaporation processes between the two models; b) provide common �winter processes� (simulation of freezing, thawing, freeze-drying processes); c) add water erosion specific input (hillslope length, slope, etc.) and output (water erosion, runoff, etc.) to the current standalone WEPS interface; d) address restrictions to simulating a homogeneous region represented by a single soil with common management practices applied to the entire field; and e) provide the necessary inputs to represent water erosion specific practices, such as terraces, artificial drainage, etc. to the user interface. The Wind Erosion Prediction System (WEPS) model was installed on 15,000 USDA computers including 2,200 NRCS field offices nationwide beginning October, 2010. NRCS is using WEPS for: a) assisting land managers in controlling wind erosion; b) establishing acceptable field level conservation plans; and c) determining wind erosion susceptibility as part of the Conservation Reserve Program (CRP) and other national conservation program enrollments. The WEPS model is a critical component of the USDA strategy to reduce particulate emissions from cultivated agricultural lands. ARS scientists at Manhattan, KS continue work to improve the WEPS model which includes development of more maintainable computer code to allow expansion to more complex field configurations and regional simulations. Research was initiated to provide more detailed output of erosion losses as affected by hills, wind barriers, and field boundaries. An improved weather database has been developed and incorporated into WEPS. Plant growth routines are being expanded for multiple crops within a field to simulate situations such as double cropping and weed competition. A laser- based system was developed and used in the field which allows for detailed yet rapid and easy measurement of soil roughness. WEPS has been modified for use as part of a dust warning system and a paper published on using WEPS to predict regional dispersion of particulate emissions from soil. A user requirements document was delivered to customers which outlines a WEPS based system to predict wind erosion from construction and other disturbed lands. A research plan was also developed to study potential emission of fine dust particulate matter less than 2.5 microns (PM2.5). Work continues to incorporate water erosion routines into WEPS in an effort to provide both wind and water erosion in one combined model. Collaborative field research by ARS scientists from Manhattan, KS and Lubbock, TX continued in Florida and Michigan to investigate the wind erodibility of highly productive but highly erodible organic matter dominated soils. Field wind tunnel tests were completed and new field sites selected to study the effects of weather and management on changes in wind erodibility of these soils. Laboratory analysis was also completed for a study seeking to determine the effects of applied municipal biosolids on wind erosion from farmlands. WEPS was used to determine the potential effects on wind erosion of plant residue removal for bio-energy. Three chapters were completed for an upcoming USDA Agricultural Handbook: WEPS Technical Documentation. Field experiments were conducted and data collected for a study at Ft. Riley, Kansas to determine the effects of military training vehicle (M1A1- Abrams Tank and Humvee) traffic on soil wind erodibility and potential dust emissions. This DOD funded research is part of a larger project which includes similar studies on different soil types, climatic regimes, and vegetation components. This study will contribute to the prediction of wind erosion and particulate emissions as a result of military training activities and allow better management of such lands to control dust emissions. Accomplishments 01 Wind Erosion Prediction System implemented by USDA-Natural Resources Conservation Ssrvice. Wind erosion is a severe problem on cultivated agricultural lands throughout the US. ARS researchers at Manhattan, KS, developed the Wind Erosion Prediction System (WEPS) model at the request of the USDA Natural Resources Conservation Service (NRCS) for improved wind erosion prediction technology. In 2010, NRCS began using the model on 15,000 computers in its 2,200 field offices nationwide for all new conservation plans where wind erosion is a problem. NRCS is using the model for: assisting land managers in controlling wind erosion; establishing acceptable field level conservation plans; and determining wind erosion susceptibility as part of the Conservation Reserve Program (CRP) and other national conservation program enrollments. The model is critical component of the USDA strategy to reduce particulate emissions from cultivated agricultural lands. 02 Wind erosion of organic dominated soils. Wind erosion is a serious problem on the highly productive organic dominated soils in the US. ARS scientists from Manhattan, KS and Lubbock, TX, completed field wind tunn research in Florida and Michigan to investigate the wind erodibility of these soils. Equations derived from this work will be used to predict soil loss on these soils. This work was deemed critical by USDA Natural Resources Conservation Service (NRCS) and ARS to the application of the Wind Erosion Prediction System (WEPS) on these highly productive but highly erodible soils. This research will allow land managers to select from alternative management scenarios to reduce or control wind erosion. 03 Predicting pathways of windblown dust. Dust from eroding farm and other lands can have regional impacts on both rural and urban air quality. AR researchers at Manhattan, KS, collaborating with scientists from Mexico, combined the Wind Erosion Prediction System (WEPS) erosion submodel with an air quality model to study of the effect of wind erosion on fine dust production and movement around Mexico City. The published results establish the importance of wind erosion from the dry Lake of Texcoco an agricultural lands to the East and South-East of Mexico City on urban ai quality, its genesis, morphology, and regional implications. The combin erosion and air quality model provide a useful computational tool to stu the wind erosion phenomenon, its sources, and impact on rural and urban regions. 04 Laser roughness meter. Wind erosion research and prediction demand accurate measurements of soil surface roughness. A laser-based, field portable, measurement system capable of obtaining surface elevations wit sub-centimeter accuracy was developed by ARS researchers in Manhattan, K and used in the field for the first time in 2010. This system provides more accurate and rapid determination of soil roughness as a parameter affecting wind erodibility. This technology will support the Wind Erosi Prediction System (WEPS) by determining soil roughness input parameters.

Impacts
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Publications

• Diaz, E.N., Tatarko, J., Jazcilevich, A.D., Garcia, A.R., Caetano, E., Ruiz-Suarez, L.G. 2010. A modeling study of aeolian erosion enhanced by surface wind confluences over Mexico City. Aeolian Research. 2:143-157. doi:10.1016/j.aeolia.
• Mamedov, A.I., Wagner, L.E., Huang, C., Norton, L.D., Levy, G.J. 2010. Polyacrylamide effects on aggregate and structure stability of soils with different clay mineralogy. Soil Science Society of America Journal. 74(5) :1720-1732.
• Hagen, L.J. 2010. Erosion by Wind: Modeling. In: Lal, R. editor. Encyclopedia of Soil Science: Second Edition. London: Taylor and Francis publishers. p. 1-4.
• Tatarko, J., Stefonick, N.A. 2007. Wind Erodibility of Biosolids - Amended Soils: A Status Report. Water Environment Federation. 12(5):12-15