TITLE:
Application of Parametric-Based Framework for Regionalisation of Flow Duration Curves
AUTHORS:
Martins Yusuf Otache, Muhammad Abdullahi Tyabo, Iyanda Murtala Animashaun, Lydia Pam Ezekiel
KEYWORDS:
Regionalisation, Parametric, Models, Anthropogenic, Hydro-Climatic Variations
JOURNAL NAME:
Journal of Geoscience and Environment Protection,
Vol.4 No.5,
May
17,
2016
ABSTRACT: It is common knowledge that the end user of stream flow data may
necessarily not have any prior knowledge of the quality control measures
applied in their generation, therefore, conclusions drawn most often times may
not be effective as desired. Thus, this study is an attempt at providing an
independent quality construct to boost the confidence in the use of stream flow
data by developing regional flow duration curves for selected ungauged stations
of the upper Niger River Basin, Nigeria. Toward this end, stream flow data for
seven gauging stations cover some sub basins in the Basin were obtained; precisely,
monthly stream flow data covering a range of eleven to fifty-three years
period. The flow duration curves from the gauging stations were fitted with
three probability distribution models; i.e.,
logarithmic, power and exponential regression models. For the regionalisation,
parameterisation was carried out in terms of the drainage area alone to allow
for simplicity of models. Results obtained showed that the exponential
regression model, in terms of Coefficient of Determination (R2) had
the best fit. Though the regionalised model was simple, measurable agreement
was obtained during the calibration and validation phases. However, considering
the length of data used and probable variability in the stream flow regime, it
is not possible to objectively generalise on the quality of the results.
Against this backdrop, it suffices to take into cognisance the need to use an
ensemble of catchment characteristics in the development of the flow duration
curves and the overall regional models; this is important considering the
implications of anthropogenic activities and hydro-climatic variations.