|Sommer, R - CIMMYT MEXICO|
Submitted to: Agronomy Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: November 3, 2003
Publication Date: December 6, 2003
Citation: WHITE, J.W., SOMMER, R. 2003. DATA INPUT AND OUTPUT AS USED IN DIFFERENT APPROACHES TO MODELING TILLAGE. AGRONOMY ABSTRACTS. CD-Rom (A03-White284709-poster). Technical Abstract: Efforts to model effects of tillage practices and residue management can collaborate more effectively if routines use similar inputs and outputs - within constraints imposed by different modeling approaches and processes simulated. A review of existing models suggests key input parameters for tillage (and related field operations) include time of the tillage event, depth of tillage, whether the profile is inverted (e.g., through moldboard plowing), portion of surface residue incorporated, degree of mixing over the specified depth, conversion of standing residue to flat residue, and effects on surface roughness (or SCS curve number), bulk density, and pore structure. "Biopedoturbation," soil mixing by soil fauna, is somewhat analogous to mechanical tillage but occurs continuously rather than being event-driven. Generic values for soil mixing, depth and portion of residue incorporated are available, but parameters are probably best determined locally, a situation somewhat analogous to characterization of soil profiles and cultivar coefficients. State variables that are affected by tillage processes mainly characterize the soil surface and profile. Surface residue parameters may include mass, spatial cover (and distribution), portion of residue standing, albedo, characteristics affecting incorporation and decomposition, and contribution to surface roughness.