Field measurements of interrill erosion under �different slopes and plot sizes

Abstract

Despite numerous studies, the effect of slope on interrill erosion is not clearly established. Several interactions exist between erosion parameters that are not taken into account under experimental laboratory measurements and results need to be validated in the field. The influence of slope steepness (2 to 8 per cent) on soil loss for a crusted interrill area and the detachment and transport processes involved in the interaction between slope, rain characteristics and plot size were investigated. Sediment discharge and runoff rates were measured in bounded plots (1 m 2 and 10 m 2 ) under natural and simulated rainfall, allowing the analysis of a combination of detachment and transport processes at various scales in the field. Runoff rate increased from 20 to 90 per cent with increasing slope and rain intensity for both plot sizes, whereas sediment concentration increased from 2 to 6 g l À1 with increasing slope only for the 10 m 2 plots. At the 1 m 2 scale, erosion was transport-limited due to the reduced rain-impacted flow. Interactions between slope angle and rain intensity were observed for detachment and transport processes in interrill erosion. Results show the importance of an adapted experimental set-up to get reference data for interrill erosion model development and validation.

Causes and underlying processes of measurement variability in field erosion plots in Mediterranean conditions

“…Secondly, the lower values for the plots compared to catchment scales can be explained by the plot length: the flow is not able to gain enough energy for effective sediment transport. Chaplot and Le Bissonais (2000) explain the transport-limited conditions of small plots as due to reduced rain impacted flow and limited flow velocity. Furthermore at both plot scales (1 m 2 and 30 m 2 ) temporal exhaustion of sediment can occur during the events, as was demonstrated by Puigdefábregas et al (1999).…”

The temporal changes in road stormwater runoff quality and the implications to first flush control in Chongqing, China

“…The reason for this difference is probably because of the quick convergence of runoff from the slope (10°) in our study. Chaplot and Le Bissonnais (2000) and Fang et al (2008) found also that the larger slope gradient could lead to higher flow velocity and increased runoff generation capacity. Similar temporal patterns were shown between TSS and TP.…”

Effect of Rainfall Regime and Slope on Runoff in a Gullied Loess Region on the Loess Plateau in China

“…In addition, for No. 5 plot, its larger slope gradient and lower position on the slope surface could lead to larger flow velocity and higher soil moisture content downslope and leave less time to infiltrate into the soil that increased runoff generation capacity (Chaplot and Le Bissonnais 2000).…”