Topography significantly influencing low flows in snow-dominated watersheds
Open Access
- 20 March 2018
- journal article
- research article
- Published by Copernicus GmbH in Hydrology and Earth System Sciences
- Vol. 22 (3), 1947-1956
- https://doi.org/10.5194/hess-22-1947-2018
Abstract
Watershed topography plays an important role in determining the spatial heterogeneity of ecological, geomorphological, and hydrological processes. Few studies have quantified the role of topography in various flow variables. In this study, 28 watersheds with snow-dominated hydrological regimes were selected with daily flow records from 1989 to 1996. These watersheds are located in the Southern Interior of British Columbia, Canada, and range in size from 2.6 to 1780 km2. For each watershed, 22 topographic indices (TIs) were derived, including those commonly used in hydrology and other environmental fields. Flow variables include annual mean flow (Qmean), Q10 %, Q25 %, Q50 %, Q75 %, Q90 %, and annual minimum flow (Qmin), where Qx % is defined as the daily flow that occurred each year at a given percentage (x). Factor analysis (FA) was first adopted to exclude some redundant or repetitive TIs. Then, multiple linear regression models were employed to quantify the relative contributions of TIs to each flow variable in each year. Our results show that topography plays a more important role in low flows (flow magnitudes ≤ Q75 %) than high flows. However, the effects of TIs on different flow magnitudes are not consistent. Our analysis also determined five significant TIs: perimeter, slope length factor, surface area, openness, and terrain characterization index. These can be used to compare watersheds when low flow assessments are conducted, specifically in snow-dominated regions with the watershed size less than several thousand square kilometres.Keywords
This publication has 38 references indexed in Scilit:
- Landscape controls on spatiotemporal discharge variability in a boreal catchmentWater Resources Research, 2016
- An approach for assessing impact of land use and biophysical conditions across landscape on recharge rate and nitrogen loading of groundwaterAgriculture, Ecosystems & Environment, 2014
- Exploring the physical controls of regional patterns of flow duration curves – Part 1: Insights from statistical analysesHydrology and Earth System Sciences, 2012
- Hierarchical controls on runoff generation: Topographically driven hydrologic connectivity, geology, and vegetationWater Resources Research, 2011
- Regime‐dependent streamflow sensitivities to Pacific climate modes cross the Georgia–Puget transboundary ecoregionHydrological Processes, 2007
- Comparison of grid‐based algorithms for computing upslope contributing areaWater Resources Research, 2006
- Relative Importance for Linear Regression inR: The PackagerelaimpoJournal of Statistical Software, 2006
- Persistence of topographic controls on the spatial distribution of snow in rugged mountain terrain, Colorado, United StatesWater Resources Research, 2005
- A new topographic index to quantify downslope controls on local drainageWater Resources Research, 2004
- Linking parameters across scales: Subgrid parameterizations and scale dependent hydrological modelsHydrological Processes, 1995