nerc.ac.uk

Classifying low flow hydrological regimes at a regional scale

Kirkby, M.J.; Gallart, F.; Kjeldsen, T.R.; Irvine, B.J.; Froebrich, J.; Lo Porto, A.; De Girolamo, A.. 2011 Classifying low flow hydrological regimes at a regional scale. Hydrology and Earth System Sciences, 15 (12). 3741-3750. 10.5194/hess-15-3741-2011

Full text not available from this repository.

Abstract/Summary

The paper uses a simple water balance model that partitions the precipitation between actual evapotranspiration, quick flow and delayed flow, and has sufficient complexity to capture the essence of climate and vegetation controls on this partitioning. Using this model, monthly flow duration curves have been constructed from climate data across Europe to address the relative frequency of ecologically critical low flow stages in semi-arid rivers, when flow commonly persists only in disconnected pools in the river bed. The hydrological model is based on a dynamic partitioning of precipitation to estimate water available for evapotranspiration and plant growth and for residual runoff. The duration curve for monthly flows has then been analysed to give an estimate of bankfull flow based on recurrence interval. Arguing from observed ratios of cross-sectional areas at flood and low flows, hydraulic geometry suggests that disconnected flow under "pool" conditions is approximately 0.1% of bankfull flow. Flow duration curves define a measure of bankfull discharge on the basis of frequency. The corresponding frequency for pools is then read from the duration curve, using this (0.1%) ratio to estimate pool discharge from bank full discharge. The flow duration curve then provides an estimate of the frequency of poorly connected pool conditions, corresponding to this discharge, that constrain survival of river-dwelling arthropods and fish. The methodology has here been applied across Europe at 15 km resolution, and the potential is demonstrated for applying the methodology under alternative climatic scenarios.

Item Type: Publication - Article
Digital Object Identifier (DOI): 10.5194/hess-15-3741-2011
Programmes: CEH Topics & Objectives 2009 - 2012 > Water
CEH Sections: Boorman
ISSN: 1027-5606
Additional Information. Not used in RCUK Gateway to Research.: Open Access article - click on the Official URL link for full text
NORA Subject Terms: Hydrology
Date made live: 04 Jan 2012 16:12
URI: http://nora.nerc.ac.uk/id/eprint/16208

Actions (login required)

View Item View Item