Runoff formation from experimental plot, field, to small catchment scales in agricultural North Huaihe River Plain, China

Abstract

Abstract. Runoff formation at an experimental plot (1600 m 2 ), a field (0.06 km 2 ), and a small catchment (1.36 km 2 ) with a shallow groundwater table and a dense drainage system in the agricultural North Huaihe River Plain (China) was analysed based on the observed rainfall, runoff, and groundwater table data of 30 storm events that occurred during the 1997 to 2008 flood seasons. The surface runoff was collected and measured at the outlet of the furrow of the experimental plot, whereas the total runoff was collected and measured at the outlets of the drainage ditches of the field and the small catchment. The present study showed that the relatively narrow range of rainfall amounts resulted in significantly different runoff amounts at the 3 scales. When the groundwater is close to the surface, the runoff amount is a large percentage of the total rainfall. The difference in rainfall and runoff amounts was regressed against changes in the groundwater table, and a significant linear relationship was determined. Significant rainfall-runoff relationships were indicated for the events divided into 3 groups according to the initial groundwater table depths (as indicators of the antecedent moisture conditions): less than 0.5 m, more than 2.1 m, or between 0.5 m and 2.1 m. These findings suggest that saturation excess surface flow dominated the runoff response, particularly when the groundwater table was shallow. For almost all events, the groundwater table rose above the bottom of the drainage ditch. The total runoff amounts were larger both at the field and at the catchment than at the plot with only the surface runoff collected, which shows a considerable contribution of subsurface flow. Groundwater table depth, which indicates antecedent moisture conditions and influences lateral sub-surface flow to the drainage ditches, is an important parameter that influences runoff formation in catchments, including the study area with a shallow groundwater table and a dense drainage system.

Effects of a deep-rooted crop and soil amended with charcoal on spatial and temporal runoff patterns in a degrading tropical highland watershed

“…Our findings are in agreement with other studies that show that rainfall-runoff relationships at a small plot scale are different than at the outlet (e.g., Han et al, 2012;Stoof et al, 2012), and that better use of green water (rainfall) for smallholder agriculture systems in the Ethiopian highlands could be achieved by decreasing runoff by increasing the storage of water in the root zone. However, more research has to be done on how best to achieve the latter.…”

Reconstruction and characterization of the surface drainage system functioning during extreme rainfall: the analysis with use of the ALS-LIDAR data—the case study in two small flysch catchments (Outer Carpathian, Poland)

“…When man-origin lines (especially roads) modify runoff pattern their applicability may be limited. Therefore, the models of the catchment contributing to the streams development were developed, on the basis of statistical analyses of physiographic parameters which significantly influence on the overland-flow formation process (e.g., Gil 1999;Han et al 2012). This approach allowed to generate the first elements of the SDS, with regard to the spatial diversity of the land cover.…”

“…(1) empirically on the basis of field studies; (2) by use of the empirically determined relationship between contributing area and local valley slope at the head channel; or (3) using probabilistic approach (e.g., Kirby 1980;Dietrich et al 1987;Montgomery and Dietrich 1988;Istanbulluoglu et al 2002;Takken et al 2008;Henkle et al 2011;Julian et al 2012;Płaczkowska et al 2015). In this study, the head channel area was calculated on the basis of the statistical analyses of physiographic parameters which significantly influence on the overland-flow formation process (e.g., Gil 1999;Han et al 2012). This approach allowed to develop the models of the catchments contributing to the streams development.…”

“…A surface drainage system (SDS) controls catchment hydrology and acts as an indicator of geologic and geomorphologic processes (e.g., Daniel 1981;Dietrich et al 1987;Loaugue and VanderKwaak 2002;Croke at al. 2005;Rodriguez-Iturbe et al 2009;Henkle et al 2011;Han et al 2012;Kroczak and Bryndal 2015;Kroczak et al 2016;Galia at al. 2017).…”

Improved SCS-CN Method Based on Storage and Depletion of Antecedent Daily Precipitation

“…Corn, cotton, and soybean were planted in the field and catchment areas. Precipitation and runoff were measured with a rain gauge and an outlet flow measurement device, respectively (Han et al 2012). …”