Landscape Element Contributions to Storm Runoff

Abstract

Hydrological conditions and the corresponding land area contributions to streamflow vary across the landscape. Landscapes are mosaics that can be described in varying levels of detail. This document describes the importance of different landscape elements for storm runoff generation. Since topography is often a first‐order control on hydrological processes, topographic indices can be used to describe the spatial variations of hydrological conditions. Another approach is the delineation of landscape elements. We suggest that riparian and hillslope areas are the two most basic landscape elements that need to be considered; however, additional landscape elements including urban areas, floodplains, croplands, wetlands, and so on, can also be important. Landscape elements can be defined through hydrological analysis. This analysis can further define their lateral connections and organization along the stream network, providing valuable interpretation of the dominant controls on hydrological response across the landscape. Additionally, approaches to represent landscape elements in hydrological modeling are reviewed.

Implications of hydrologic connectivity between hillslopes and riparian zones on streamflow composition

“…For example, the generation of a wetland in the western part of the basin that covers~5.3% of the total area indicates that these valley bottom areas are fully saturated most of the year. These results support the discretization of the URHBlandscape into riparian zones and hillslopes following the framework proposed by Seibert and McGlynn (2005). In the URHB, riparian zones contain areas with high TWI, which are located predominantly in the valley bottoms with Gleysols and peaty soils.…”

“…1c). Based on the hydrometric observations and following the framework presented by Seibert and McGlynn (2005), the Büel site was divided into a hillslope section (piezometers P1-P4) and a riparian zone (piezometers P5-P8).…”

“…The delineation of hydrological relevant landscape units of a catchment is closely linked to the dominant streamflowgenerating mechanisms taking place on those areas (Seibert and McGlynn, 2005). Several studies applied this concept in combination with tracer experiments and hydrometric data in order to identify the relevant source areas of hydrograph components and the active flow pathways (e.g., Detty and McGuire, 2010;Jencso and McGlynn, 2011;McGlynn et al, 2004).…”

“…In order to scale up the findings from the hillslope-to the catchment scale and to locate those areas in the URHB topographic indices can be applied. For example, the topographic wetness index (TWI, Beven and Kirkby, 1979) is widely used in order to identify potential source areas for streamflow contribution and as a proxy for shallow groundwater table distribution (e.g., Detty and McGuire, 2010;James and Roulet, 2007;Seibert and McGlynn, 2005). Fig.…”

Mapping dominant runoff processes: an evaluation of different approaches using similarity measures and synthetic runoff simulations

“…In addition to traditional topographical descriptors (e.g. elevation, slope, and exposition), these methods are based on the HAND value, which represents, in turn, a rearrangement of the "elevation-above-stream" proposed by Seibert and McGlynn (2006). HAND-based classifications have been used to define classes of soil water environments, where a single runoff generation mechanism dominates (Nobre et al, 2011;Gao et al, 2014).…”