Soil water balance Daily rainfall is disaggregated into shorter period intensities. Water is allowed to pond at the surface and crop residues can store water as well. Runoff occurs only when the soil's ponding capacity is exceeded. The ponding capacity varies with the equipment used. Tillage also affects the saturated hydraulic conductivity of the macropores or rate of infiltration and bulk density of the tilled layers.
All parameters approach a settled value with time.
Residues Tillage affects the amount of residues left on the surface. Residues decompose with time as a function of moisture and temperature. Residues also affect soil water evaporation. Soil temperature Thickness of the residue layer affects upper boundary maximum and minimum soil temperature. Results and Conclusions Comparisons between simulated and observed soil temperatures at 4.5 cm depth are shown in Fig 2 and Fig 3 for 1997.