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. However, during the summer months of July and August, the model tended to underpredict soil temperature for all treatments. References Dadoun, F. 1993.