About Book

As the world faces an increasingly critical need to address climate change, the impact that water conservation has on a sustainable environment is undeniable. Groundwater is the primary source of freshwater that caters to the demand of ever-growing domestic, agrarian and industrial sectors of the country. Our water resources are depleting each year. Additionally, we cannot generate artificial water and must depend on water sources available on our planet earth. Due to population boom and excessive need of water to suit our ever-expanding modern lifestyle, water scarcity is felt all over the world. This has given rise to major concerns over water conservation. Reserving rainwater can help recharge local aquifers, reduce urban flooding and most notably, ensure water availability in water-scarce zones. Soil and water are two important natural resources and the basic needs for agricultural production. Soil water conservation is defined as the control of soil erosion in order to maintain agricultural productivity. This book presents the recent advances in water harvesting and soil water conservation. It focuses on sediment transport, storage volume, evapotranspiration estimation, time stability, global wavelet coherency and biofilm. It also deals with mechanisms of soil water-solute and non-rainfall periods. It is compiled in such a manner, that it will provide in-depth knowledge about the theory and practice of this field. The topics covered in it offer the readers new insights about this subject. Different approaches, evaluations and methodologies on the subject have been included in the book, thus making it an invaluable source of knowledge. This book aims to serve as a resource guide for researchers and contribute to the growth of the discipline.

Preface............................................................................................................v

Chapter 1 Analysis of Non-Rainfall Periods and Their Impacts on the Soil Water Regime...............................................................................................1

Abstract...................................................................................................1

1. Introduction............................................................................................2

2. Materials and methods........................................................................3

3. Results and discussion.........................................................................8

4. Conclusions..........................................................................................22

Acknowledgements.............................................................................23

Chapter 2 Experimental Study on the Mechanisms of Soil Water-Solute-Heat Transport and Nutrient Loss Control..................................................25

Abstract.................................................................................................25

1. Introduction..........................................................................................25

2. Materials and methods......................................................................28

3. Results and discussions.....................................................................37

4. Conclusions..........................................................................................63

Acknowledgements.............................................................................64

Chapter 3 Role of Biofilm in Rainwater Tank......................................................69

Abstract ................................................................................................69

1. Introduction..........................................................................................70

2. Method and materials........................................................................71

3. Results and discussions.....................................................................79

4. Suggestion of a design and maintenance guideline for rainwater

system....................................................................................................93

Chapter 4 Scale Dependence and Time Stability of Nonstationary Soil

Water Storage in a Hummocky Landscape Using Global

Wavelet Coherency...................................................................................98

1. Introduction..........................................................................................98

2. Theory.................................................................................................100

3. Materials and methods....................................................................102

4. Results.................................................................................................106

5. Discussions.........................................................................................111

6. Summary and conclusions..............................................................113

Acknowledgments.............................................................................113

Chapter 5 Time Stability of Soil Water Content................................................119

1. Introduction........................................................................................119

2. Concept...............................................................................................120

3. Methodology......................................................................................122

4. Application.........................................................................................133

5. Controlling factors............................................................................146

6. Conclusion..........................................................................................151

Acknowledgements...........................................................................152

Chapter 6 Critical Evaluation of Different Techniques for Determining Soil

Water Content..........................................................................................158

1. Introduction........................................................................................158

2. State of water in the soil.................................................................159

3. Gravimetric water content...............................................................162

4. Neutron scattering............................................................................163

5. Tensiometers.......................................................................................167

6. Porous blocks.....................................................................................169

7. Time domain reflectometry.............................................................171

8. Impedance and capacitance methods...........................................175

9. Conclusions........................................................................................177

Chapter 7 Estimation of Evapotranspiration Using Soil Water

Balance Modelling ................................................................................180

1. Introduction .....................................................................................180

2. The one dimensional vertical soil water balance equation ..182

3. Review of various parameterizations of actual

evapotranspiration .........................................................................188

4. Rainfall runoff hydrological models .........................................198

5. Conclusions........................................................................................209

6. Annexe ...............................................................................................210

Chapter 8 Evapotranspiration Estimation Using Soil Water Balance, Weather

and Crop Data ........................................................................................222

1. Introduction ......................................................................................222

2. Field experiment ..............................................................................223

3. Soil water balance method ............................................................225

4. Crop coefficient method .................................................................226

5. Results and discussion ...................................................................237

6. Conclusion .........................................................................................241

7. Acknowledgments ...........................................................................242

Chapter 9 Determination of the Storage Volume in Rainwater Harvesting

Building Systems: Incorporation of Economic Variable ..............245

1. Introduction........................................................................................245

2. Particle swarm optimization ..........................................................247

3. Methods..............................................................................................248

4. Results ................................................................................................251

5. Conclusion..........................................................................................268

6. Abbreviation list ..............................................................................269

Chapter 10 Sediment Transport in Rainwater Tanks and Implications for

Water Quality...........................................................................................272

1. Introduction........................................................................................272

2. Methodology .....................................................................................278

3. Results ................................................................................................283

4. Discussion .........................................................................................296

5. Conclusion .........................................................................................297

6. Acknowledgement ...........................................................................298

Citation......................................................................................................301

Index...........................................................................................................303

About Author

Ricardo Cui attained his Master of Environmental Science in Land and Water Management from the University of Science & Research, Minas Gerais. He is an Assistant Professor at Technical Institute, Montevideo. He is actively engaged in the researches focused on water management practices, water metering and rainwater harvesting. Cui has authored and edited several texts, which include articles, technical papers and book chapters, in the fields of water management. He was also awarded the “University Excellence in Teaching” award for his outstanding contribution to the student community in the field of water conservation.