Interrill and rill erosion as affected by plot configuration on a sandy loam Hapludalf soil

The objective of this study was to compare rill and interrill erodibility a nd critical shear stress, for two configurations of soil surface: rectangul ar (RCS) and triangular (TCS) cross-sections. The experiment was done in 19 98 on a conventionally tilled Hapludalf with a sandy loam soil surface text ure. The interrill plot dimensions were 0.50 by 0.75 m, while for rill, the dimensions were 0.20 by 5.90 m for RCS, and 0.50 by 5.90 m for TCS. Consta nt simulated rain of 65 mm h(-1) was applied on the interrill plots for 90 minutes, whereas for the rills, besides rain to prewet the soil, five extra inflows of 0.0002 m(3) s(-1) up to 0.0010 m(3) s(-1) were applied. The int errill detachment rate Di (2.09x10(-4) kg m(-2) s(-1) for RCS and 3.35x10(- 4) kg m(-2) s(-1) for TCS), interrill erodibility Ki (1.77x10(6) kg s m(-4) for RCS and 2.00x10(6) kg s m(-4) for TCS), rill erodibility Kr (0.0110 kg N-1 s(-1) for RCS e 0.0074 kg N-1 s(-1) for TCS), and critical shear stres s tauc (2.61 N m(-2) for RCS e 2.00 N m(-2) for TCS) were not statistically different for the two cross-sections, and can be determined on any of the plot configuration for sandy loam soils.