ARS | Publication request: MODELING EFFECTS OF TILL/NO-TILL AND SURFACE CROP RESIDUES ON SOIL WATER, TEMPERATURE AND ENERGY BALANCE

Submitted to: Soil Tillage Research Organization International Conference Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: July 1, 2006
Publication Date: September 1, 2006
Citation: Ahuja, L.R., Anapalli, S.S., Ma, L., Kozak, J.A., Aiken, R.M., Flerchinger, G.N. 2006. Modeling effects of till/no-till and surface crop residues on soil water, temperature and energy balance. International Soil Tillage Research Organization. Kiel, Germany, August 28-September 3, 2006.

Interpretive Summary: No-tillage and crop residue management is an important practice for conserving soil and water. Surface residue amount and architecture (flat vs. standing) significantly impact infiltration, runoff, and erosion, as well as evaporation, soil water storage, and soil temperature.Residue effects on the soil energy balance can influence plant growth and development. We review the state of science of modeling crop residue effects on the above processes in current models of agricultural systems. We present the results of the Root Zone Water Model (RZWQM) for simulating soil water in tilled vs. no-tilled wheat-corn-fallow rotation. We also present RZSHAW,a new hybrid model that extends the applications of RZWQM to conditions of different tillage and crop residue types and architectures using complete energy balance. RZ-SHAW allows three different methods of surface energy flux to be used: (1) The Simultaneous Heat and Water (SHAW) mode; (2) the Shuttleworth-Wallace (S-W) mode; and (3) the PENFLUX mode.Applications of RZ-SHAW for simulating soil water and temperature in fallow plots at Akron, CO are presented. Additionally, effects of the percent residue cover on residue interception of rainfall were incorporated in the model. Interception was shown to decrease infiltration, deep percolation, and runoff, but increase overall ET.

Technical Abstract: No-tillage and crop residue management is an important practice for conserving soil and water. Surface residue amount and architecture (flat vs. standing) significantly impact infiltration, runoff, and erosion, as well as evaporation, soil water storage, and soil temperature.Residue effects on the soil energy balance can influence plant growth and development. We review the state of science of modeling crop residue effects on the above processes in current models of agricultural systems. We present the results of the Root Zone Water Model (RZWQM) for simulating soil water in tilled vs. no-tilled wheat-corn-fallow rotation. We also present RZSHAW,a new hybrid model that extends the applications of RZWQM to conditions of different tillage and crop residue types and architectures using complete energy balance. RZ-SHAW allows three different methods of surface energy flux to be used: (1) The Simultaneous Heat and Water (SHAW) mode; (2) the Shuttleworth-Wallace (S-W) mode; and (3) the PENFLUX mode.Applications of RZ-SHAW for simulating soil water and temperature in fallow plots at Akron, CO are presented. Additionally, effects of the percent residue cover on residue interception of rainfall were incorporated in the model. Interception was shown to decrease infiltration, deep percolation, and runoff, but increase overall ET.