Estimating spatial patterns of soil erosion and deposition in the Andean region using geo-information techniques A case study in Cochabamba, Bolivia Promotor: Prof. B. Schultz, PhD, MSc. Professor of Land and Water Development UNESCO-IHE & Wageningen University (WUR) Delft, The Netherlands Co-Promotor: Dr. Ir. C. M. M. Mannaerts Associate Professor Department of Water Resources, ITC Enschede, The Netherlands Examining committee: Prof. Dr. Ir. D. Gabriels University of Gent Gent, Belgium Prof. Dr. Ir. L. Stroosnijder Wageningen University Wageningen, The Netherlands Prof. Dr. D. Lobo, MSc. Universidad Central de Venezuela (UCV) Caracas, Venezuela Prof. Dr. L. D. Norton, MSc. Purdue University Purdue, USA Estimating spatial patterns of soil erosion and deposition in the Andean region using geo-information techniques A case study in Cochabamba, Bolivia Carlos Saavedra THESIS to fulfil the requirements for the Degree of Doctor of Philosophy on the authority of the Rector Magnificus of Wageningen University, Prof. Dr. M.J. Kropff, to be publicly defended on Tuesday, December 6th 2005 at 15:00 hrs in the auditorium of ITC, Enschede This publication has been submitted as a Ph.D. dissertation in partial fulfilment of the requirements for the award of the degree of Doctor at Wageningen University, The Netherlands, 6th December 2005. Copyright © Carlos Saavedra, p/a ITC & Wageningen University 2005. Niets uit deze uitgave mag worden vermenigvuldigd en/of openbaar gemaakt door middel van druk, fotokopie of op welke andere wijze dan ook zonder voorafgaande schriftelijke toestemming van de uitgevers. All rights reserved. No part of this publication may be reproduced in any form, by print or photo print, microfilm or any other means, without written permission of the publishers. ISBN: 90-8504-289-5 ITC Dissertation Number: 128 International Institute for Geo-Information Science and Earth Observation Enschede, The Netherlands A mi querida mamá Table of contents ACKNOWLEDGEMENTS........................................................................................ IX ABSTRACT ................................................................................................................. XI GENERAL INTRODUCTION .....................................................................................3 1.1 PROBLEM STATEMENT.......................................................................................3 1.2 SIGNIFICANCE OF SOIL EROSION AND SEDIMENTATION IN THE ANDEAN REGION OF SOUTH AMERICA.......................................................................................................5 1.3 AIMS, OBJECTIVES AND RESEARCH QUESTIONS .................................................8 1.4 OUTLINE OF THE THESIS ....................................................................................9 EROSION PROCESSES, MODEL REVIEW AND SELECTION.........................15 2.1 INTRODUCTION................................................................................................15 2.2 EROSION, DEPOSITION AND SEDIMENT TRANSPORT PROCESSES .......................15 2.3 A SHORT REVIEW OF EROSION AND SEDIMENT TRANSPORT MODELS................20 2.4 SCALE AND SCALING ISSUES IN EROSION MODELLING .....................................27 2.5 TEMPORAL SCALE IN EROSION MODELLING .....................................................31 2.6 REMOTE SENSING AND GIS IN EROSION MODELLING.......................................32 2.7 MODEL SELECTION..........................................................................................34 2.8 SUMMARY .......................................................................................................43 DESCRIPTION OF THE STUDY AREA..................................................................49 3.1 INTRODUCTION................................................................................................49 3.2 BOLIVIAN ANDES ............................................................................................49 3.3 COCHABAMBA PROVINCE................................................................................51 3.4 LAKA-LAKA CATCHMENT ...............................................................................55 3.5 RESERVOIR AND LAKES ...................................................................................68 REGIONAL-SCALE EROSION MODELLING USING GLOBAL COARSE- RESOLUTION SATELLITE DATA AND GEODATA...........................................73 4.1 INTRODUCTION................................................................................................73 4.2 DATA AND METHODS.......................................................................................73 4.3 DISTRIBUTED EROSION MODELLING ................................................................78 4.4 RESULTS AND DISCUSSION ..............................................................................83 4.5 CONCLUSIONS .................................................................................................94 CATCHMENT-SCALE EROSION MODELLING USING MEDIUM- RESOLUTION SATELLITE IMAGERY AND LIMITED GROUND DATA ......99 5.1 INTRODUCTION................................................................................................99 5.2 DATA AND METHODS.......................................................................................99 5.3 RESULTS AND DISCUSSION ............................................................................111 5.4 CONCLUSIONS ...............................................................................................123 RESERVOIR SEDIMENTATION ASSESSMENT USING ACOUSTIC GEOREFERENCED SONAR SOUNDING AND GIS...........................................127 6.1 INTRODUCTION..............................................................................................127 i 6.2 METHODS AND DATA ....................................................................................130 6.3 RESULTS AND DISCUSSION ............................................................................140 6.4 CONCLUSIONS ...............................................................................................153 ANALYSING LINKAGES BETWEEN CATCHMENT GROSS EROSION AND RESERVOIR SEDIMENTATION...........................................................................159 7.1 INTRODUCTION..............................................................................................159 7.2 SPATIAL SEDIMENT DELIVERY RATIO MODELS ..............................................162 7.3 DATA PROCESSING ........................................................................................167 7.4 RESULTS AND DISCUSSION ............................................................................170 7.5 CONCLUSIONS ...............................................................................................177 EVALUATION...........................................................................................................183 PROBLEM STATEMENT AND OBJECTIVES ....................................................................183 EROSION MODEL SELECTION ......................................................................................184 STUDY AREA ..............................................................................................................185 REGIONAL-SCALE ANALYSIS ......................................................................................185 CATCHMENT-SCALE ANALYSIS ..................................................................................186 RESERVOIR SEDIMENTATION......................................................................................187 LINKING GROSS CATCHMENT EROSION TO RESERVOIR SEDIMENTATION.....................190 FINAL REMARKS.........................................................................................................191 REFERENCES...........................................................................................................193 SAMENVATTING.....................................................................................................209 RESUMEN..................................................................................................................215 RESUMO ....................................................................................................................227 ABBREVIATIONS AND ACRONYMS ..................................................................231 SYMBOLS ..................................................................................................................235 CURRICULUM VITAE ............................................................................................237 ITC DISSERTATION LIST......................................................................................239 ii List of Figures Figure 1.1 Effects of erosion processes in land degradation 4 Figure 1.2 Causes of soil degradation 6 Figure 1.3 Overview of the spatial and temporal resolutions of model simulation and remotely sensed data used in the different chapters 11 Figure 2.1 The main factors controlling the process of soil erosion by water (source: Symeonakis, 2001) 16 Figure 2.2 Raindrop falling on exposed soil breaking of soil particle to be lost in runoff water: a) raindrop velocity, b) raindrop impact 16 Figure 2.3 Erosion and transport on inter-rill and rill areas (source: Harmon and Doe, 2001) 17 Figure 2.4 Schematic view of rill, inter-rill areas and gullies on a sub-catchment (source: Harmon and Doe, 2001) 18 Figure 2.5 Schematic representation of the erosion and deposition from a hillslope