Table Of ContentINTEGRATED MODELING
OF LAND AND WATER RESOURCES
IN TWO AFRICAN CATCHMENTS
INTEGRATED MODELING
OF LAND AND WATER RESOURCES
IN TWO AFRICAN CATCHMENTS
DISSERTATION
Submitted in fulfillment of the requirements of
the Board for Doctorates of Delft University of Technology
and
of the Academic Board of the IHE-Delft
Institute for Water Education
for
the Degree of DOCTOR
to be defended in public on
Monday,19 March 2018, at 10:00 hours
in Delft, the Netherlands
by
Seleshi Getahun YALEW
MSc Water Science and Engineering, UNESCO-IHE, Delft, The Netherlands
BSc Information Systems, Addis Ababa University, Addis Ababa, Ethiopia
born in Dessie, Ethiopia
This dissertation has been approved by the
promotor: Prof.dr.ir. P. van der Zaag
promotor: Prof.dr.ir. A.B.K. van Griensven
Composition of the doctoral committee:
Chairman Rector Magnificus TU Delft
Vice-Chairman Rector IHE Delft
Prof.dr.ir. P. van der Zaag IHE Delft / TU Delft, promotor
Prof.dr.ir. A.B.K. van Griensven IHE Delft /Vrije Universiteit Brussels, promotor
Independent members:
Prof.dr.ir. N.C. van de Giesen TU Delft
Prof.dr. W. Bewket Alemayehu Addis Ababa University, Ethiopia
Prof.dr. A. Lehmann University of Geneva, Switzerland
Dr. N. Deligiannis Vrije Universiteit Brussels, Belgium
Prof.dr.ir. H.H.G. Savenije TU Delft (reserve member)
CRC Press/Balkema is an imprint of the Taylor & Francis Group, an informa business
© 2018, Seleshi Getahun Yalew
Although all care is taken to ensure integrity and the quality of this publication and the
information herein, no responsibility is assumed by the publishers, the author nor UNESCO-
IHE for any damage to the property or persons as a result of operation or use of this
publication and/or the information contained herein.
A pdf version of this work will be made available as Open Access via
http://repository.tudelft.nl/ihe This version is licensed under the Creative Commons
Attribution-Non Commertial 4.0 International License,
http://creativecommons.org/licenses/by-nc/4.0/
Published by:
CRC Press/Balkema
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ISBN 978-1-138-59338-1
To my mother
For her patience and understanding,
Because she always believes.
ማስታወሻነቱ፤ ለታጋሽና ጽኑ እናቴ ይሁንልኝ።
ACKNOWLEDGEMENTS
First and foremost, my sincere gratitude is due to Professor Pieter van der Zaag and Professor
Ann van Griensven who have been there as my supervisors during this journey and have been
unstinting in their support and constructive critique. Their choice of suggestion as opposed to
dogma during their supervision has especially been my favorite and a constant inspiration for
me to aspiring for independent research in integrated land and water resources research.
Many thanks are also due to Dr. Marloes Mul and many other coauthors to my papers, some
of which are part of this thesis, for positively contributing towards my growth in the realm of
environmental research.
My heartfelt thanks and appreciation goes also to my wife, Lideta, and my children, Sophia
and Alula, for different reasons: the earlier for giving me the space and the time to work on
my dissertation, including the late nights and the weekends, and the latter for consistently
reminding to creating laughter and fun.
Finally, I am grateful for the financial contribution by the AFRIMASON, AQUAREHAH,
and NWO-WOTRO projects towards my PhD study. Similarly, I am thankful to all agencies
and individuals who shared their local and regional environmental datasets.
SUMMARY
Land and water are two of the most important and interacting natural resources that are
critical for human survival and development. Growing population and global economic
expansion are accelerating the demand for land and water for uses such as agriculture,
urbanization, irrigation, hydropower, and industrialization. The land surface changes
dynamically due to these demands and other socio-economic drivers. Biophysical factors
such as topographic suitability, climate change, and rainfall variability further influence land-
use changes and land-use change decisions. Water resources are likewise experiencing
pressure from overuse, pollution, and changes in hydrologic processes as a result of both
socio-economic and biophysical factors.
Land and water resources are considered to have strong interactions. Although the science of
this interaction is not new, the two are typically managed under separate governance systems
(Le Maitre et al., 2014). As a result, land-use change and hydrology or water resources are
studied usually separately. Modelers and model developers reproduced the existing
separation in governance of land and water resources in their respective models, which gave
rise to mild treatment of one of the resources when analyzing the other. The result is that
hydrology and water resources are often considered to be processes and resources affected
only by biophysical components, ignoring anthropogenic contributions that may actually
influence such characteristics through direct effects on land-use, for instance.
The need to understand and explicitly represent the interaction between water resources on
the one hand and land-use changes with its drivers on the other is imperative for sustainable
management of integrated natural resources management in general and land and water
resources management in particular. In recent years, interesting sub-disciplines such as
‘socio-hydrology’ are emerging which recognize and emphasize the importance of socio-
economic and anthropogenic effects on hydrologic and water resources analysis. Interaction
and feedback between land-use and water resources is still not explicitly and dynamically
represented in most scientific modeling tools related to land and water, however.
Furthermore, often due to limitations of access and computing resources, frameworks for
communicating integrated assessment and modeling in a way that can be operational to
resource managers and decision makers related to such resources is limited. This is especially
evident in developing regions.
