Up-scaling surface runoff from plot to catchment scale

Abstract

The main aims of this study were to identify and characterize the flow processes at the plot scale, and to up-scale these processes at the catchment scaie by Terrain Analysis, using Digital Elevation Models (TauDEMs) based on in-situ sprinkling experiments. To calibrate the TauDEM-based method at the plot scale, in-situ sprinkling experiments were carried out on two plot scales (16 m^ divided into 16 plots of 1 m^ on various slopes). The marked differences in the textural and structural porosities between forest and grassland soil appear to control runoff processes. While grassland soils were characterized by a variable subsurface flow depending mainly on field slope, deep percolation was mainly found in forest soils. In addition, the map of flow directions also shows that two factors play an important role: on the one hand, the spatial sequence of the areas with a predisposition to surface runoff, and on the other, the tortuosity and length of channels that enhance the cumulative water volume in the target outlets. When based on sprinkling experiments, the TauDEM-based method provides more quantitative information on the dynamic of flow at the catchment scale. Furthermore, additional investigations are needed to validate the calculations of flow at a larger scale.

Modelling the effects of land use and climate changes on hydrology in the Ursern Valley, Switzerland

“…The higher porosity in green alder soil is due to the more intense root system of green alder that loosens the soil structure and promotes vertical infiltration (also limiting surface runoff generation). Similar results were found by Alaoui et al (2012) when grassland soil was compared to forest soil. The authors showed higher storage capacity in forest soil as compared to grassland soil, caused by the more intense root system having a significant effect on surface runoff (decrease).…”

“…Similar results were found by Alaoui et al . () when grassland soil was compared to forest soil. The authors showed higher storage capacity in forest soil as compared to grassland soil, caused by the more intense root system having a significant effect on surface runoff (decrease). In Chämleten, the inverse phenomenon occurred (Figure ).…”

Trade-off between surface runoff and soil erosion during the implementation of ecological restoration programs in semiarid regions: A meta-analysis

“…The effects of vegetation restoration on different kinds of soil erosion (i.e., river bank erosion and gully erosion) might be different. How to up-scale the soil erosion process to the larger scale is worth considering (Alaoui et al, 2012). Therefore, further studies should focus on analysing the effects of re-vegetation types on overland flow velocity, soil erosion control and surface water resource protection at different scales (i.e., landscape, hillslope, hydrologic response unit and patch).…”

Fifteen essential science advances needed for effective restoration of the world's forest landscapes

“…Such studies are very useful in exploring hydrological processes (such as infiltration, overland flow, sediment transport and subsurface water flow) and local-level interactions among climate, soil, vegetation, topography and management practices [ 110 ]. However, plot-level parameters measured in situ cannot be expected to produce accurate predictions at all scales [ 111 ], and there are uncertainties when extrapolating findings from plot to catchment scales, or from small to large catchments [ 112 ]. The link between plot-scale and catchment-scale outcomes is critical for hydrological outcomes to be fully considered in landscape-level forest restoration planning.…”