 |
| Titel |
Classifying low flow hydrological regimes at a regional scale |
| VerfasserIn |
M. J. Kirkby  , F. Gallart, T. R. Kjeldsen, B. J. Irvine, J. Froebrich, A. Porto, A. Girolamo, MIRAGE Team |
| Medientyp |
Artikel
|
| Sprache |
Englisch
|
| ISSN |
1027-5606
|
| Digitales Dokument |
URL |
| Erschienen |
In: Hydrology and Earth System Sciences ; 15, no. 12 ; Nr. 15, no. 12 (2011-12-19), S.3741-3750 |
| Datensatznummer |
250013054
|
| Publikation (Nr.) |
 copernicus.org/hess-15-3741-2011.pdf |
|
|
|
|
|
| Zusammenfassung |
| 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. |
| |
|
| Teil von |
|
|
|
|
|
|
|
|