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How Climate and Land Use Determine the Hydrology of Lake Naivasha Basin

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How Climate and Land Use Determine the Hydrology of Lake Naivasha Basin How climate and land use determine the hydrology of Lake Naivasha Basin Vincent Omondi Odongo Graduation committee: Chair: Prof.dr.ir. A. Veldkamp University of Twente Promoter: Prof.dr. Z. Su University of Twente Co-promoter: Dr.ir. C. van der Tol University of Twente Members: Prof.dr. A. van der Veen University of Twente Prof.dr.ing. W. Verhoef University of Twente Prof.dr. J.D. Albertson Cornell University, Ithaca, USA Prof.dr. L. Jia Chinese Academy of Sciences, China Prof.dr. J.O. Onyando Egerton University, Kenya Dr. A. Olioso INRA, Avignon, France ITC dissertation number 291 ITC, P.O. Box 217, 7500 AA Enschede, The Netherlands ISBN 978-90-365-4233-3 DOI 10.3990/1.9789036542333 Cover designed by Benno Masselink Printed by ITC Printing Department Copyright © 2016 by V.O. Odongo How climate and land use determine the hydrology of Lake Naivasha Basin DISSERTATION to obtain the degree of doctor at the University of Twente, on the authority of the rector magnificus, prof.dr. H. Brinksma, on account of the decision of the graduation committee, to be publicly defended on Thursday 3rd November 2016 at 16.45 hrs by Vincent Omondi Odongo born on 13-05-1977 in Nakuru, Kenya This thesis is approved by Prof. dr. Zhongbo Su, promoter Dr. Christiaan van der Tol, co-promoter Acknowledgements This thesis was an outcome of support received from many organizations, institutions and people. I acknowledge the funding received from NWO-WOTRO for funds that supported this thesis research through the Earth Observation and Integrated Assessment (EOIA) of Lake Naivasha Project. I also acknowledge ITC-fellowship and ESA-Tiger project for supporting the latter part of this work. I appreciate the support of Water Resources Management Authority (WRMA) for the support with data and their hospitable staff who were at the forefront to assisting with logistics during fieldwork. I acknowledge Kenya Wildlife Service (KWS) and Kenya Wildlife Service Training Institute (KWSTI) for providing the access to their sites where the flux measurement equipment were installed. Specifically, the support of Prof. George Otiang’a Owiti is greatly acknowledged. It is through your support that KWSTI and ITC partnership remains great and continues to date. I would like to express my special appreciation and thanks to my promotor Prof. Dr. Bob Su, you have been a tremendous mentor for me. I would like to thank you for encouraging my research and for allowing me to grow as a research scientist. I also would like to thank my co-promotor Dr. Christiaan van der Tol. Your advice on both research as well as on my career have been priceless. I thank Drs. Robert Becht for his support and mentorship throughout my MSc to PhD studies. Your support and belief in me is unmatched. I appreciate the support of Dr. Zoltan Vekerdy and Ir. Arno van Lieshout during the latter part of this thesis. Your contribution and support was timely and much needed. The EOIA Naivasha project team led by Prof. Anne van der Veen and Prof. Japheth Onyando provided invaluable support that made my work harmonious and were always there to support when needed. I also acknowledge the contribution and support of Prof. Nzula Kitaka, Prof. George Khroda and Prof. Jude Mathooko during the many scientific and stakeholder presentations we had in Naivasha, Dr. Pieter van Oel is thanked for the many valuable scientific debates, arguments, discussions and most importantly the fun times we had in Naivasha and the Netherlands with the rest of the team members. Dr. Dawit Mulatu, Dr. Francis Kamau, Job Ogada and Dr. Jane Ndung’u are appreciated for the many wonderful times spent together and the support shared. I appreciate the support and times spent with the EOIA MSc. Students who participated in the project: Frank Meins, Mark Cornelissen and Rick Hogeboom. I wish to thank co-authors who also contributed and significantly participated in my work and led to publication of some of the chapters in this thesis. I acknowledge the valuable constructive criticisms by Prof. Andrew Skidmore and Dr. Thomas Groen that led to publication of Chapter 5. I acknowledge the contribution of Dr. Joost Hoedjes and Dr. Ghimire Chandra that led to the publication of Chapter 4. I also appreciate the contribution of Dr. Joris Timmermans and Dr. Xuelong Chen on working with SEBS. Many thanks and appreciation to Dominic Wambua who was of great assistance during my field work. Your local knowledge was unparralled and significant during data collection. The many friends I met and interacted with made ITC an enabling social environment and my stay enjoyable: Dr. Tagel Gidey, Dr. Jennifer Kinoti, Dr. Shadrack Ngene, Dr. Zacharia Kuria and Dr. Abel Ramoelo. I wish to express my gratitude to Tina Butt-Castro and Anke de Koning, Loes Colenbrander and Marion Pierik for the attention and care they continually exuded. I acknowledge the resourcefulness of Murat Ucer in helping with testing the field equipment and also responding in time when I had technical issues with the equipment in the field. A special thanks to my family. Words cannot express how grateful I am for all the sacrifices you made on my behalf. To Uncle John and Family, a big thank you cannot tell it all, but I appreciate your tremendous support and for always being there for me. I would also like to thank all of my friends who supported me to strive towards my goal and were always there in the moments when there was no one to answer my queries. ii Table of Contents Acknowledgements ................................................................................................. i List of figures ....................................................................................................... vi List of tables ......................................................................................................... x 1 Introduction .................................................................................................... 1 1.1 Background .............................................................................................. 2 1.2 Integrated assessment of Lake Naivasha Basin ............................................. 5 1.3 Problem statement .................................................................................... 6 1.4 Objectives ................................................................................................ 7 1.5 Description of study area ........................................................................... 7 1.6 Thesis outline ......................................................................................... 10 2 A characterisation of hydro-climatological trends and variability in the Lake Naivasha Basin, Kenya ...................................................................................................... 11 2.1 Introduction ........................................................................................... 13 2.2 Study area and data ................................................................................ 14 2.3 Methods ................................................................................................. 17 2.3.1 Lake volume change and water balance analysis ................................... 17 2.3.2 Change point analysis........................................................................ 19 2.3.3 Trend analysis .................................................................................. 21 2.3.4 Trend analysis under STP hypothesis ................................................... 22 2.3.5 Trend analysis under scaling hypothesis .............................................. 23 2.3.6 Double mass curve analysis ............................................................... 25 2.4 Results .................................................................................................. 25 2.4.1 Lake volume change and water balance ............................................... 25 2.4.2 Autocorrelations ............................................................................... 30 2.4.3 Change point analysis........................................................................ 31 2.4.4 Double mass curve analysis ............................................................... 37 2.4.5 Trend analysis .................................................................................. 39 2.5 Discussion .............................................................................................. 45 2.6 Conclusions ............................................................................................ 47 3 Estimating the evaporative water loss of different land use and land cover in the upper Lake Naivasha Basin ................................................................................... 49 3.1 Introduction ........................................................................................... 51 3.2 Methods ................................................................................................. 53 3.2.1 Study area ....................................................................................... 53 3.2.2 Ground instrumentation and data processing ........................................ 54 3.2.3 Remote sensing products and meteorological data ................................ 55 3.2.4 Observed runoff and precipitation data ................................................ 56 3.2.5 Implementing SEBS .......................................................................... 56 3.3 Results and discussions ..........................................................................
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