Water is one of the most important natural resources covering 75 percent of the Earth's surface. It is a major component of living organisms contributing to about 60 percent of the human body. Different European environmental monitoring programmes confirm that the current land and water resources in Europe are extremely vulnerable and subject to a range of external pressures. Water management needs to be implemented with caution following thorough evaluation. Therefore, it is crucial for the current generation to manage and preserve water resources for future generations in a sustainable way. Current human development patterns suggest that in the future there will be an increase in population, population density and an increase in agglomerations. These global change patterns (of land use and climate) add additional pressures on water resources and it might increase probability of flood events.
This problem has been recognized in recent years not only by scientists, but also by policy makers. Therefore in October 2000, the European Parliament adopted the Directive 2000/60 /EC (the EU Water Framework Directive-WFD).The WFD defines the water management objectives that need to be reached in the near future by the different member states of the EU. Since the use of natural resources in a sustainable way is one of the priorities of the European environmental agenda, sustainable exploitation and use of water resources is a key objective of the WFD. The WFD adopts a holistic approach to river water management and envisages the involvement of different actors in the design of future water management plans. Furthermore, the principles of future water management plans should be based on state-of-the-art knowledge of the functioning of the hydro-system and should be based on the sustainable exploitation of water resources. Unfortunately, the hydro-system is complex, involving many compartments, processes, and boundary conditions which vary in space and time. This makes the description of the evolution of the hydro-system for alternative potential management scenarios a difficult task. In such a context, the design of water resource management plans must inevitably adopt a multidisciplinary, multi-participatory approach, considering the pressures exerted by global change drivers and will be based strongly on the use of hydrological models.
List of tables...................................................................................................6
List of figures..................................................................................................8
List of figures..................................................................................................8
List of abbreviations.......................................................................................9 Acknowledgements.......................................................................................11
Chapter 1. Introduction.............................................................................13
1.1. Introduction............................................................................................13
1.1.1. Water Framework Directive (WFD)................................15
1.1.2. Integrated modelling.........................................................17
1.2. Objectives..............................................................................................19
1.3. Outline of the methodology...................................................................19
1.4. Outline of the thesis...............................................................................21
Chapter 2. Study region and data.............................................................23
2.1 Description of the Dyle catchment.........................................................23
2.2. The Dyle catchment- administrative situation.......................................26
2.3. Available data sets for the Dyle catchment............................................28
2.3.1. River discharges...............................................................28
2.3.2. Weather data set...............................................................29
2.3.3. GIS data............................................................................30
2.4. The study sub-catchments......................................................................31
2.4.1.The Thyle catchment.........................................................31
2.4.2. The Nethen catchment......................................................31
Chapter 3. Hydrological models................................................................33
3.1. Introduction............................................................................................33
3.2. WFD – a modellers perspective.............................................................33
3.3. Hydrological modelling to support Integrated Water Resource Management.................................................................................................36
3.3.1. Hydrological model selection criteria..............................36
3.3.2. Classification of models used in hydrology.....................37
3.4. Model selection for Integrated Water Resource Management within the Belgian case study........................................................................................39
3.5. The Geographical Information Systems in hydrological models...........47
3.5.1. Coupling GIS to hydrological models..............................48
3.6. Model used for the Dyle application......................................................49
3.6.1. The Soil and Water Assessment Tool (SWAT)...............50
3.6.1.1. SWAT model – data preparation and parameterisation.................................................................50
3.6.1.1.1. SWAT model and GIS.......................................51
3.6.1.1.2. SWAT model data sets.......................................52
3.6.2. Meshed Hydrological Model - MHM..............................52
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3.6.3. Comparison between the SWAT model and the MHM...53
3.7. Conclusion.............................................................................................55
Chapter 4. Sensitivity of the SWAT model to the soil and land use data parameterisation: a case study in the Thyle catchment, Belgium..........57
4.1. Introduction............................................................................................57
4.2. Materials and methods...........................................................................58
4.2.1 Model description..............................................................58
4.2.2 The catchment area............................................................59
4.2.3.General input data.............................................................60
4.2.3.1. Soil parameterisation.............................................62
4.2.3.2. Modelling..............................................................63
4.2. 4 Model evaluation..............................................................64
4.2.4.1 Evaluation of the pre-processing............................64
4.2.4.2 Evaluation of the hydrological modelling..............65
4.3. Results and discussion...........................................................................67
4.3.1 Evaluation of the generic land use and soil map...............67
4.3.2 Evaluation of the hydrological modelling.........................73
4.4. Conclusion.............................................................................................77
Chapter 5. Storm basin management for a flooding event in an ungauged catchment...................................................................................79
5.1. Introduction............................................................................................79
5.2. Flooding- problems in the Nethen sub-catchment.................................80
5.3. Scenarios development..........................................................................82
5.4. Definition of the model evaluation data set...........................................83
5.5. Application of the SWAT model to the Nethen catchment...................84
5.6. Results....................................................................................................86
5.7. Discussion and conclusion.....................................................................88
Chapter 6. Deriving global change scenarios for hydrological modelling in the Dyle catchment.................................................................................91
6.1.Introduction.............................................................................................91
6.2. Future Scenario Construction................................................................91
6.2.1.Overview...........................................................................91
6.3. Climate change scenarios.......................................................................95
6.3.1 Climate change scenarios for the Dyle catchment............95
6.4. Land use change scenarios.....................................................................97
6.4.1. The ATEAM Land use change scenarios in the Dyle catchment....................................................................................97
6.5. Land use change downscaling method for the Dyle catchment...........101
6.5.1. Introduction....................................................................101
6.5.2. Material and Methods.....................................................103
6.5.2.1. Data preparation..................................................103
6.5.2.2. Logistic regression analysis.................................104
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6.5.2.3. Deriving the explanatory variables for the Dyle.107
6.5.3. Results............................................................................110
6.5.4. Discussion......................................................................114
6.6.Conclusions...........................................................................................117
Chapter 7. Impact of environmental change on the hydrology of the Dyle.............................................................................................................119
7.1. Introduction..........................................................................................119
7.2. Model parameterisation.......................................................................120
7.2.1.Land cover data set of the SWAT model........................120
7.2.2. Transfer of CSTV parameterisation to the Dyle............123
7.3. Modelling.............................................................................................125
7.4. Results..................................................................................................126
7.5. Discussion............................................................................................130
7.6. Conclusions..........................................................................................132
Chapter 8. Conclusions and Perspectives...............................................135
8.1.Conclusions...........................................................................................135
8.2. Perspectives.........................................................................................140
8.3. Recommendations................................................................................142 References...................................................................................................143
Web pages...................................................................................................154
Annex I.......................................................................................................155
Annex II......................................................................................................157
Annex III.....................................................................................................169
Annex IV....................................................................................................174
Annex V......................................................................................................177
Annex VI....................................................................................................179