Desertification, Land Degradation and Sustainability E-Book

Anton Imeson

• Herausgeber: John Wiley & Sons
• Kategorie: Wissenschaft und neue Technologien
• Sprache: Englisch

Seitenzahl: 646

Veröffentlichungsjahr: 2012

Beschreibung

Desertification offers a comprehensive overview of the subject and clearly emphasizes the link between local and global desertification processes and how past and current policy has affected arid environments and their populations.

This text adequately applies the research undertaken during the last 15 years on the topic. Desertification has become increasingly politicized and there is a need to present and explain the facts from a global perspective. This book tackles the issues surrounding desertification in a number of ways from differing scales (local to global), processes (physical to human), the relationship of desertification to current global development and management responses at different scales. Desertification has been mainstreamed and integrated into other areas of concern and has consequently been ignored as a cross cutting issue. The book redresses this balance.

Making use of much original data and information that has been undertaken by many scientists andpractitioners during the last decade in different parts of the world, Desertification, Land Degradation and Sustainability is organised according to the principles of adaptive management and hierarchy theory and clearly explains desertification within a framework of evolving and interacting physical and socio-economic systems. In addition to research data the book also draws from the National Action Plans of different countries, the IPCC Fourth Assessment on Climate Change and the Millennium assessments.

Clearly structured throughout, the content of the book is organised at different scales; local, regional and global. It also specifically explains processes linking top-down and bottom- up interactions and has a strong human component. The historical, cultural and physical context is also stressed.

Clearly organised into the following distinct sections:

a) Concepts and processes

b) Data

c) Impacts

d) Responses

e) Case studies.

This text is essential for anyone studying desertification as part of an earth and environmental science degree.

Leseprobe

Table of Contents

Titlepage

Copyright

Dedication

Preface

Acknowledgement

Introduction: Scope and Approach

Reference

Part I: The Nature of Desertification

Chapter 1: Desertification, Its Causes and Why It Matters

1.1 The Nature of Desertification

1.2 The Links between Global and Local Desertification

1.3 Discussion: Desertification as a World-Wide and Historical Phenomenon

1.4 Discussion: Life and Its Feedback with the Environment

1.5 Discussion: The Adaptation of People and Cultures to Desertification

1.6 Discussion: Data and Evidence for Land Degradation

1.7 Conclusion: Why Land Degradation and Desertification Occur

References and Further Reading

Chapter 2: Responses to Desertification

2.1 Finding Answers

2.2 Conclusion: The Causes of Land Degradation Today

2.3 Conclusion: Strategies to Mitigate Desertification

References and Further Reading

Chapter 3: Desertification Indicators: From Concept to Practice

3.1 Introduction

3.2 Approaches to Desertification Indicators

3.3 Global and Regional Indicators of Land Degradation and Desertification

3.4 Applying Selected Concepts in Practice

3.5 Desertification, Resilience and Stability

3.6 The Soil and Water Conservation and Protection Functions

3.7 Spatial Variability and Discontinuity

3.8 Hydrological Indicators of Desertification

3.9 Water in the Soil and Landscape

References and Further Reading

Part II: Local Desertification Impact and Response

Chapter 4: Key Processes Regulating Soil and Landscape Functions

4.1 Introduction

4.2 Fine Scale Processes

4.3 The Provision of the Hydrological Function, Runoff and Sediment Transport

4.4 The Protection Function of the Land and Erosion

4.5 The Long-Term Impact: the Vigil Network Sites in the USA

4.6 Hydrological Response: What Happens to the Land When It Rains

4.7 Water

4.8 Nature, Natural Capital and Land Degradation

4.9 Soil Stability

4.10 Soil Response and Soil Behaviour

4.11 Catchment Response, Hydrology and the Soil

4.12 Discussion: Vegetation Patterns as Responses to Land Degradation Processes

4.13 Controlled Desertification Experiments

References and Further Reading

Chapter 5: Human Impact on Degradation Processes

5.1 Introduction

5.2 Soil Erosion Processes

5.3 Response of Soil Structure to Cultivation and Farming

5.4 Gully Erosion

5.5 Grazing and Erosion

5.6 The Impact of Fire on Land Degradation Processes

5.7 Case 1: Blue Ridge Foothills

5.8 Case 2: Human Impact in the Atlantic States

5.9 Case 3: Impact of Forest Logging in California Casper Creek

5.10 Case 4: Karuah Forest, New South Wales, Australia

5.11 Case 5: Afforestation in Spain

5.12 Case 6: Soil Erosion Impacts in Europe

5.13 Case 7: Human Impact in the Central Cordillera of Columbia

5.14 Case 8: Bolivia Tarije

5.15 The Sediment Load and Soil Erosion

5.16 Monitoring Methods to Verify Impact and Management on Erosion

5.17 Water Resource Development Irrigation as Responses

5.18 Soil Conservation Principles and Erosion

5.19 Conceptual Approaches to Soil Conservation

References and Further Reading

Chapter 6: Responses to Land Degradation from Perception to Action

6.1 Introduction

6.2 Environmentally Sensitive Areas

6.3 The European Policy, Response, and Governance

6.4 Applying the Adaptive Systems Approach Explicitly

6.5 Responding with Laws to Protect the Land and Soil

6.6 European Law and the Requirements of the Convention

6.7 The European Soil Strategy

6.8 Romania: A Model National Action Plan

6.9 Italy and the Convention

References and Further Reading

Part III: Global Desertification Impact and Response

Chapter 7: Global Desertification Today

7.1 Desertification Today

7.2 Global Balances and Fluxes

7.3 Case Study: Desertification and the Crash in Property Prices

7.4 Brazil

7.5 Namibia

7.6 Dust and Sandstorms in China

References and Further Reading

Chapter 8: Desertification, Ecosystem Services and Capital

8.1 Introduction

8.2 Interactions between Desertification and Ecosystem Services

8.3 The Impact of Desertification on Ecosystem Services

References and Further Reading

Chapter 9: The Way Forward: Global Soil Conservation and Protection

9.1 Introduction

9.2 Iceland

9.3 The Call for Action

9.4 Europe

9.5 Support to the UNCCD

9.6 The Importance of International Co-Operation

References and Further Reading

Appendix A: Soil Basics

References and Further Reading

Index

This edition first published 2012

© 2012 John Wiley & Sons, Inc.

Wiley-Blackwell is an imprint of John Wiley & Sons, formed by the merger of Wiley's global Scientific, Technical and Medical business with Blackwell Publishing.

Registered office: John Wiley & Sons, Ltd, The Atrium, Southern Gate, Chichester, West Sussex, PO19 8SQ, UK

Other Editorial Offices:

9600 Garsington Road, Oxford, OX4 2DQ, UK

111 River Street, Hoboken, NJ 07030-5774, USA

For details of our global editorial offices, for customer services and for information about how to apply for permission to reuse the copyright material in this book please see our website at www.wiley.com/wiley-blackwell.

The right of the author to be identified as the author of this work has been asserted in accordance with the Copyright, Designs and Patents Act 1988.

All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording or otherwise, except as permitted by the UK Copyright, Designs and Patents Act 1988, without the prior permission of the publisher.

Wiley also publishes its books in a variety of electronic formats. Some content that appears in print may not be available in electronic books.

Designations used by companies to distinguish their products are often claimed as trademarks. All brand names and product names used in this book are trade names, service marks, trademarks or registered trademarks of their respective owners. The publisher is not associated with any product or vendor mentioned in this book. This publication is designed to provide accurate and authoritative information in regard to the subject matter covered. It is sold on the understanding that the publisher is not engaged in rendering professional services. If professional advice or other expert assistance is required, the services of a competent professional should be sought.

Library of Congress Cataloging-in-Publication Data

Imeson, Anton.

Desertification, land degradation, and sustainability / Anton Imeson.

p. cm.

Includes bibliographical references and index.

ISBN 978-0-470-71448-5 (cloth)—ISBN 978-0-470-71449-2 (pbk.)

1. Desertification. 2. Desertification–Control. 3. Reclamation of land. I. Title.

GB611.I44 2012

333.73′6–dc23

2011022871

A catalogue record for this book is available from the British Library.

This book is published in the following electronic formats: ePDF 978-1-119-97776-6; Wiley Online Library 978-1-119-97775-9; ePub 978-1-119-97978-4; Mobi 978-1-119-97979-1

To my wife Jane

Preface

The land soil and water are the most precious natural resources we have. However, human actions that started 5000 years ago continue to cause an ever decreasing decline in their quality and value. More than 20 years of research has shown that desertification and land degradation can be stopped and large areas restored of their quality. Protecting and restoring the functions and services that have been lost by the land and soil is seen as the key to sustainable development and reversing climate change.

The approach of this book has been to make a synthesis of research findings and communicate the essence of these in a practical way so that the reader can have information about the causes of desertification and its nature, how it is being measured and its impact and what can and is being done about it. This book then is a study of mans impact on nature and whether limits need to be placed on the appropriation of water and land. So much work has been done that it only possible to select a few examples that scientifically underpin the conclusion.

Because processes of desertification are a consequence of culture, climate and geology, and the main drivers are land use and development, these need to be presented in a coherent framework understandable to people with different experience. This has been done in several different ways using indicators, the concepts of functions and ecosystem goods and services, systems and change, desertification response units, ecosystem health and soil quality, hierarchy theory and adaptive management. Some basic principles and key processes are explained from hydrology, erosion, soil degradation, ecology soils because these need to be appreciated by people responsible for policy and legislation. Similarly some basic principles from the economic and social sciences are applied so that the cultural drivers of land degradation give more guidance in restoration. Land use, Agriculture, and Development are important but the main thing is how people see value and treat the land unaware of the influence on processes. Desertification is a story of mans impact on earth so an effort has been made not to include too much detail regarding case studies because this can be found in the cited literature.

The book is also an introduction to and a case study of Geography, Applied Geography, Physical Geography, Natural Resource Management, Soil Conservation and Environmental Law and Environmental Politics and ethics.

The book also describes many indicators and measurements that can be made. This is particularly with respect to soil and land degradation.

Inevitably, as it is about actions and responses to desertification, the book examines and analyses the role of the UNCCD, United Nations Convention to Combat Climate Change and European Soil Conservation Policy and their influence.

However, this book is not just academic because the reader, like the author is a stakeholder. Policies that stop land degradation and reverse it could be introduced overnight but it requires seriousness, effort and organization. As the causes and processes of land degradation are similar everywhere, it is possible to treat desertification both locally and globally. At the end of the book, the Selfoss Call to Action is included so that the reader can see what is actually being thought and recommended by scientists from Environmental Law and soil conservation.

The book is organized into three main parts.

Part I, is about the Nature of Desertification.

After the scope and approach of the book are described there are three main Chapters that respectively consider respectively the causes and why it matters, Responses to Desertification and Desertification Indicators from Concept to Practice.

Chapter 1 considers the nature of desertification, its history and impact on ecosystem functions and services and the importance of life and its feedback with processes. It looks at scientific data and evidence for land degradation in research. It also discusses how and why desertification occur and the methodology.

Chapter 2 introduces the responses being made at different levels and review the causes of desertification.

Chapter 3 introduces indicator approaches, concepts and principles. It describes how selected approaches are applied in practice. It describes how indicators can be obtained from the soil and hydrological information. Resilience and stability Indicators of the different soil and land functions identified as being damaged by human actions are described. There is an introduction to water and desertification and basic principles of hydrology and soil stability.

Part 2 looks at local desertification impact and responses.

Chapter 4 describes the key processes regulating the soil and land scape functions

The hydrological and conservation functions are created and maintained and how they are related to human actions and processes in the soil and landscape. This chapter presents methods for studying change, key soil, ecological and hydrological processes. It introduces soil stability and soil response and catchment responses.

Chapter 5 is about the human impact on degradation processes. It contains an introduction to soil erosion, soil structure degradation, gully erosion, grazing impact, fire and the impacts of land use conversions. Eight short case studies from the USA, Australia, Europe and South America are used to illustrate principles. The chapter describes sediment transport data and erosion monitoring methods, impact from water resource development, Principles and Concepts of soil conservation.

Chapter 6 describes responses to land degradation from perception to action. It looks at positive experience from case studies in Europe, the United States soil conservation response of Bennett to the Dust Bowl. European soil conservation policy and responses to land degradation are described. It looks at experiences of sustainable land management obtained from the SCAPE Project into soil conservation and protection strategies for Europe. The perception is the perception that there is a problem and the action considers both the legislation and enactment of laws.

Part III is about global desertification impacts and responses.

Chapter 7 Global Desertification Today described the emergent consequence of local desertification at a global sale through land use change and the appropriation of land and water and illustrates this in Central Asia and the USA with respect to water. It describes the Millennium report and the role of the UNCCD. The impact of desertification on soil quality and functions is described. Some basic information about global fluxes is mentioned. There is a case study illustrating the impact of the financial markets and investments on land degradation. Three examples of global problems are described from Brazil deforestation, Namibia and China.

Chapter 8 looks at the impacts of desertification on ecostystem services and capital. The nature and value of natural capital is explained as are the different services provided by the land.

Finally, in Chapter 9 the way forward, the main conclusion about finding answers are elaborated in some detail, making use of the findings from international conferences and calls from action by the scientific and environmental law community.

And Part 3 is about global desertification.

Acknowledgement

Jane, Joan, Marc, David, Robert, Marlies and Manon—thank you for your feedback and encouragement when I was writing this book.

I also acknowledge the help and support of the editorial and production team of John Wiley and Sons, in particular the help from Fiona Woods. Rachael Ballard, Izzy Canning and Sarah Karim and Aishwarya are thanked for their contribution to this book and a special thanks goes to Gillian Andrews for her improvements and insights.

This book is the result of a process that began as a student and I am especially appreciative of the opportunity I had to be part of a team at Hull University with Ian Douglas, Roy Ward, Alistair Pitty, David Watts, Jay Appleton, Ian Reid, John Pitman and Les Ternan and to the NERC for supporting my PhD. Later to have an opportunity to work with Pim Jungerius and his team at the Laboratory of Physical and Geography of Soil Science of the University of Amsterdam (FGBL). Working as part of an interdisciplinary team was encouraged in the Faculty of Spatial Sciences, and I appreciate the opportunity created by others which enabled me to work in Morocco (Herman van de Wusten) in Lestoho and in Indonesia with the Free University (Theo Faber). I acknowledge the contributions made by the IGU Commissions in which I participated and who shared their research experience, particularly during field visits of the GERTEC and COMTAG Commissions (Asher Schick, Tom Dunne, Rorke Bryan, Anders Rapp, Adam Kertec, Dino Torri, Aaron Yair, Hanoch Lavee, Jean de Ploey, Anna Netto, Maria Sala, Adolfo Calvo Hans Reizebos, Theo van Asch).

I also thank the founders and members of the ESSC and the many meetings and conferences they have organised on this subject. Jose Rubio is thanked for his encouragement and many opportunities he created, most recently for example in his work with V. Andreu at the Campus de Excelencia on the human and socioeconomic consequences of desertification. I am also grateful for discussions I have had with Jeff Herrick and Luca Montanarella concerning the application of research in policy and application in the USA and Europe.

With respect to the methodology, I am grateful to Cranfield University and collaboration with Peter Allen and Janice Evans during the ERMES project in which the work of Adolfo Calvo, Pepe Rubio, Hanoch Lavee, Joachem Hill and Chico Perez Trejo is acknowledged. I am also grateful to all of those in the MEDALUS project including of course John Thornes, Jane Brandt and Nicky Geeson, Mike Kirkby. For field visits, I especially appreciate the ideas and contributions from, amongst others, Prof. Aru, Prof. Enni, Prof. Basso, Maria Roxo, Francisco Lopez Bermudez and his team as well as Costas Kosmas, Prof. Yassiglou, Prof. Puigdefabregas and Albert Sole.

I would also thank the EU DG Research for supporting desertification research for nearly 20 years. Roberto Fantechi, P. Balabanis, Denis Peter and Maria Yeroyianni are thanked for their feedback and encouragement. I would like to acknowledge the support I received in the project (EFEDA I and II, MEDALUS I, II and III), AQUDAPT, DESERTLINKS, SCAPE, LUCINDA and LEDDRA. Finally my appreciation is to the Universiteit van Amsterdam and LERG Foundation that supported the installation of the Chair in Desertification and Soil Erosion. The support of Koos Verstraten and Jan Seevink iand IBED is greatly valued for their consideration and support. Special thanks to the many research students who contributed to this work indirectly through their field research and also to the laboratory staff for the analyses.

I am very grateful for the work being done by the UNCCD and of which I have been able to make use of. I acknowledge the great efforts they are making to reduce the impacts of desertification.

Artemi Cerda offered his help on many different occasions. His investigations on sustainable and non-sustainable land use and its impact on land degradation provide real data and evidence of the nature of several processes. Also his leadership at the EGU means that land degradation has gained prominence. Michiel Curfs, Hanoch Lavee and Aaron Yair for their many contributions and insights into desertification. Dolf de Groot and the Foundation for Sustainable Development are also thanked for their support and development of the concepts of ecosystem services and capital.

With respect to soil conservation policy and land care, I am particularly grateful to the support of the Iceland Soil Conservation Service represented by Andres Arnalds and Oli Arnalds and Svein Runolfsson and for the inspiration from the Changjing River Scientific Research Institute, the soil and water conservation service and the participants of the study tours: Zhu Jiang, Xiao Xiang, Tao Xin, Yu Jicheng, Wan Caibing, Chen Wengui, He Jun, Lv Tao, Yu Jianhua, and Liu Dezhong.

I thank:

Mr. Liu Zhen, Director General of Soil Conservation Dept., Ministry of Water Resources (MWR) and Mr. Xiong Tie, Vice Commissioner of Yangtze Water Resources Commission (CWRC).

Mr. Ning Duihu, Division Chief of Soil Conservation Dept. MWR; Ms. Liao Chunyan, Director General of Soil Conservation Bureau, CWRC; and Mr. Zhou Miaojian, Director General of Auditing Bureau, CWRC.

Mr. Hu Danwen, Section Chief of Soil Conservation Bureau, CWRC in European Soil Conservation is gratefully appreciated. I am also gratefull to Hu Danwen and Piet van der Poel and Lars Anderson for their support from the EU China Europe exchange programme for their interest and support for soil conservation in Europe. Also for translating the SCAPE book into Chinese.

Thanks also to Piet van de Poel for his kindness and support in China and to Lars Anderson in Wuhan for his feedback. I thank my colleague Michiel Curfs for his support and commitment.

Finally, I would like to thank Helen Briassoulis of the Aegean University (and the other members of the LEDDRA project on Land and Ecosystem Degradation Response Assessment) for their discussions and contributions to the work Agostino Ferrara, Koutsoukos Vassilis, Abdelkader Taleb, Ahmed El Aich, Angelo Nolè Antonella de Angelis, Artemio Cerda, Claire Kelly, Concepcion Alados, Costas Kosmas, Dan Wen Hu Geoff Wilson, Giovani Quaranta, Giuseppe Mancino HongHU LIU, Katerina Kounalaki, Luca Salvati Mina Karamesouti, Mohamed Chikahoui, Nichola Geeson, Rossanna Salvia, Ruta Landgrebe Sandra Naumann Sophia Bajocco, Zhang Pingchang Vassilis Detsis, Constantinos Liarikos Minas Metaxakis, Nichola Geeson, Panagiotis Stratakis, Thanassis Kizos and Theo Iosifides.

Denis Peter provided inspiration and motivation for writing this book and Chico Perez Trejo and Dolf de Groot inspiration for the path followed so the very special appreciation is for them.

Introduction: Scope and Approach

In this book, desertification and land degradation are treated holistically from a systems perspective. By definition they are caused by human activities in the past and present, such as forest clearance, the use of fire and the use of trees for charcoal. Land degradation and desertification are therefore a consequence of man's impact on the earth's ecosystems. They are a consequence of the use of the natural resources of the land and soil by agriculture and industry and they are driven by, for example, economic activities, property development, industry and agriculture. They can in many cases be prevented or responded to by using strategies and methods to restore land and soil qualities, or by educating people regarding their relationship with and responsibility towards nature or land (Runólfsson and Andres 2004).

After reading this book the reader should have a clear understanding of how, at the local level, human actions actually affect the processes of degradation in the landscape and soil and of how process knowledge can be used to develop criteria for sustainable land use. At the global level, the links with globalization, climate change and biodiversity loss should also be clear. Throughout the book use is made of findings from field research and monitoring.

The responses being made by society to land degradation and desertification are discussed and evaluated. Part of this response is that of the United Nations Convention to Combat Desertification (UNCCD), and the way in which UNCCD addresses and defines desertification and land degradation is explained (see Chapter 3), because UNCCD has a large impact on research and it is partly responsible for governance.

The other features that distinguish this book are:

The information about land degradation processes is based on scientifically validated peer-reviewed studies. Models are used to describe certain processes, but not to make projections.The impact of desertification is explained from the perspectives of functions that are occurring in a single socio-ecologic system in which both culture and landscape quality (geology and climate) constrain and limit change.The methodological approaches used to translate concepts of indicators and of functions, dynamic systems and adaptive management in land degradation are presented with examples.The book explains and adapts the basic principles of hydrology, soil degradation and soil conservation as they affect land degradation and at the same time describes key indicators and how they can be measured and used.The link between local and global desertification is explained.

Finally, the book discusses the strategies and methods that would enable desertification to be stopped and debates whether or not this can be done.

This book can be started in each of the three parts and most of the chapters can also be read alone.

The advantage of a process-based approach is that it allows similar problems to be treated together and it is not necessary to systematically treat desertification in each country or continent. This is because the hydrological processes and geology in combination with human actions create a limited number of field situations that repeat themselves.

Reference

Runólfsson, S. and A. Andres (2004) Soil conservation at the top of the world—conservation strategies in Iceland, pp. 1–4, Conserving Soil and Water for Societyg, International Soil Conservation Organization Conference (ISCO), Brisbane, July.

Part I

The Nature of Desertification

Chapter 1

Desertification, Its Causes and Why It Matters

By definition, human induced land degradation, which is how desertification is defined, is caused by the actions of people that have a negative impact on the ‘functioning’ of the environment, as it is being eco-culturally experienced and as regards its value as a natural resource. A function is something like clean water, air and food but it can also have an aesthetic or cultural nature. Some functions can be restored and new ones created in landscapes that have become degraded with respect to their earlier state. Species and cultures differ in their capacity to survive the loss of their functions and habitat. This ‘resilience’ is reflected in how they are affected by land degradation and desertification. Resilience can be with respect to nature but also with respect to the economy and the social capital of people. Natural capital is provided by nature and it is the basis of all economic activity and human existence.

Sustainable land use and management are about establishing principles that can be brought into practice as a response to land degradation and desertification. In many cases land can have its quality and values restored and degradation can be put into reverse. Lost qualities or functions of the land can be restored through sustainable land management and with the help of natural processes. But in many cases changes are irreversible.

Parts II and III of this book include local and global level case studies. They describe key processes and attributes of landscapes relevant to desertification and give details of the actions that can be taken to ameliorate or adapt to it in different socio-environmental contexts. The cultural and economic pressures and drivers of land degradation are immense and much of the world is comprised of degraded landscapes. Because these are a consequence of our lifestyles, culture, attitudes and values they can be systematically changed by strategically planned human efforts. The situation is quite positive to the extent that the future does not have to be the consequence of actions that degrade the landscape; there can also be other actions that lead to restoration and the reversal of land degradation. The same socio-economic and financial forces that resulted in land degradation as a result of the critical values of natural processes being disregarded can be used to organize the responses that must be made.

A society with cultural values that better understands how to be in harmony with nature can be attained. (The Book of History, The Books of Zhou, The Great Norm, p. 19 in Xiao Jietu and Li Jinquan 2008)

This book introduces some of the fundamental principles and practices of land degradation and land and landscape management as they appear in 2011. It discusses the strategies, policies and actions that are being undertaken by different organizations responsible for land degradation and who are trying to deal with it. Successful strategies and approaches that can be used to reverse land degradation are well known and these are described.

The findings of European research on desertification were recently reviewed by an expert group for the European Community (Roxo 2009). Their intention was to raise awareness of the urgent state of land degradation in Europe and explain the current situation. It was also to show what Europe had achieved and what could still be done. As well as the severity and consequences of land degradation, the experts examined the main processes associated with it, such as soil and ecosystem degradation, erosion, salinization and wildfires; the causes such as climate change and land use practices, pollution, contamination and compaction; and the different landscapes in which land degradation is most concentrated.

More or less in parallel, an International Conference was organized by SCAPE (Imeson et al 2006) that brought together experts from environmental law (Hannam and de Boer 2002) and the land degradation communities. A little later, an International Forum on Soils and Society (2007) supported by the Iceland Government to celebrate 100 years' existence resulted in A Call for Action. One of the most common universal problems is that people appropriate natural resources or farm in an unsustainable way, irrespective of any law. The Brazilian Environmental Protection Agency cannot prevent the rain forest being used illegally as a source of fuel for pig iron production because it reduces the transport cost of iron ore on the way to China which generates billions of dollars each month. Or alternatively they are exempted.

The unanimous conclusion was that with the present scientific understanding, it is possible to evaluate the degree to which the actions and policies being used to address desertification are appropriate in view of scientific knowledge (Briassoulis 2010). This fortunate situation is an outcome of a large research effort in many countries and regions. There is sufficient scientific legitimacy to place land degradation at the top of the priority list of governments. This is equally true for other parts of the world, where similar knowledge and understanding has been acquired since concerns were raised at least two hundred years ago by Europeans observing the impact of land use in marginal areas in Europe but especially in South and North America.

A Holistic Systems Based Approach

When considering the nature and causes of desertification many different assumptions can be made that influence the methodology used to present what might seem to be an extremely complex environmental problem. The traditional approach is to evaluate the different factors ranging from matters such as geology, climate, economy and culture. It is difficult to be conclusive because it is hard to integrate and quantify factors that are always changing and uncertain.

A different way is to start holistically with just one system. Desertification can be conceptualized as if there is just one socio-economic system in which society finds itself with nature (for example, Huxley (1885), van der Leeuw (1998)). This way of looking at desertification was developed by several research schools in the 1990s at a time when ways of better integrating the physical and socio-economic factors affecting land degradation were being sought. In a single discipline approach it becomes clear that what is important are people's actions and what they do and the relationships between them. Addressing desertification is attainable if alternative positive cultural habits and practices are adopted since the things people do directly change the biophysical processes and alter the way in which the single system will respond.

Man and nature are in fact acting at one scale symbiotically. Symbiosis describes the close and often long-term interactions between different biological species. Symbiotic relationships can be necessary for the survival of at least one of the organisms involved. Relationships, therefore, matter because all life has contributed to the present state of the earth. Earthworms, trees and fungi are no less significant than humans in influencing the properties of the single socio-environmental earth system. All human actions that affect other life are important because of symbiosis and interdependence. Although symbiosis has received less attention than other interactions such as predation or competition, it is an important selective force behind evolution. Desertification then is about deserts and drylands such as the Judean desert (Figure 1.1) which may or may not be experience current degradation. It is also about the spread of desert-like conditions or features (Figure 1.1) as a result of human actions (Figure 1.2) in Valencia, Spain.

Figure 1.1 The Judean Desert has a socio-ecosystem that it adapted to aridity and grazing (Credit: Anton Imeson).

Figure 1.2a The Judean Desert. Desertification is about the spread of desert-like features into humid areas as a result of vegetation clearance and agriculture and exploitation of resources (Credit: Anton Imeson).

Figure 1.2b How thousands of years of social and environmental capital can be destroyed in few moments in Spain. Photograph A. Cerda 2011.

1.1 The Nature of Desertification

1.1.1 Concern About Desertification in Developed Countries

Europe and America became concerned about desertification in the 1980s (Fantechi and Margaris 1986). It was postulated that desert-like conditions might spread to southern Europe from North Africa and to the south western United States from Mexico. There was similar evidence of such desertification in north east Brazil, China, Africa and India. According to Canadian meteorologist Hare (1976) who investigated this for the United Nations, it was not clear if this was the result of human causes or climate. In neither wealthy nor poor countries is there much evidence linking poverty to desertification. Poverty has very many causes and land degradation is linked to them in historical and political contexts that are about population growth, culture and exploitation of rural populations. Desertification and land degradation can be brought about by many different things such as conflict and migration, land use and farming, water use and soil contamination. It can also be brought about by the appropriation of people's natural resources and functions and these affect both developed and developing nations. Examples of strategies, policies and laws that address these are numerous (Arnalds 2005a and b).

Modern agriculture and forestry as well and the exploitation of natural resources involves using the land in ways that withholds and prevents it from doing what it once did in the way of regulating the hydrological cycle and energy balances, transformation processes and providing food chains and food webs.

It was confirmed by the EU working group on Desertification, set up by the European Soil Forum in 2005, that the higher the subsidies, the higher the land degradation because of the pressures and disruptions that these place on ecosystems. This is true everywhere because of the way subsidies affect human behaviour. The mathematics is explained in several monographs at the Santa Fe Institute, New Mexico. The main aims of forestry and agriculture are to provide resources and food and to sustain the economy and protect jobs. These are the strategic goals of the U.S. Forest Service, for example, whose main mission is focused on their employees' needs and the increased production of timber. In achieving these rational goals, the natural and cultural environments are ignored and often degraded of their other functions (protection from flooding) and capital (value of this protection) is lost. Actions and practices take place that should in fact be regulated because they cause harm to the life with which we share a symbiotic dependence. For most people, the land is real estate and a provider of food and raw materials. Society has not been effective in promoting values that make us conscious of being symbiotically part of nature. There is a limited or lack of any legal duty of care towards the environment, land and soil. There is the real possibility that the support functions of the earth are being compromised because of the disappearance of species both on land and in the sea.

1.1.2 Desertification and Drylands

Today, the UN definition of desertification is that it is ‘human induced land degradation in dry and sub-humid regions’ (UNCCD: United Nations Convention to Combat Desertification). Another view is that desertification occurs everywhere but that it is actually most prevalent in cold regions where the low temperatures and short growing season create fragile ecosystems that lack resilience (Arnalds 2005a and b).

A different perspective has emerged in the scientific community. The United Nations Convention to Combat Desertification (UNCCD 2011) has recently reviewed its strategy. Its main purpose is to combat poverty and increase people's standards of living in dry regions. The UNCCD has become in practice an extension of the UNDP and the FAO whose objectives of reducing poverty and giving food security reflect its new strategic goals. It has launched the next decade as the decade of desertification. It gives examples of success stories in several different countries of the world. Many of these are successful not because they reduce land degradation but because they improve the livelihoods of the people in the short term.

From the perspectives of a single system, the UNCCD is an organization that is responsible for mainly monitoring the implementing of the Convention to Combat Desertification. It is an actor in the system that we are studying and some its actions may increase, decrease or do little about the actual desertification that is happening in the world.

1.1.3 The Drivers of Desertification

An obvious starting point when considering the causes of desertification is the increase in the human population from about 1 million in the Stone Age to I billion in 1850 and 6 billion in the 1990s. Technological advances have enabled man's numbers to increase and at the same time give him the tools and means with which he can cause desertification. Worst land degradation is frequently driven by top down help or investments because these ignore elementary principles regarding the nature of the processes and the aspirations of people. This is illustrated in Figure 1.3a that shows how terraces resulted in badlands when they ignored the specific properties of the soil. In Figure 1.3b, taken during a storm, that created a flash flood, that most runoff is from paths and tracks and that the terraces of the farmers were effective. In the Middle Ages in Europe monks began developing machines and tools that increased the efficiency of agriculture and this helped develop a culture that led to the agricultural revolution. It is the combined influences of technology, human numbers and culture that have made desertification and land degradation such an urgent and seemingly intractable issue. Man is one of maybe 3 million species but today consumes far more food than all of the other land animals put together. Ever since people started to use fire to improve grazing and domesticate crops and cattle, land degradation and desertification occurred and this happened everywhere. There are few areas of the world that have not been affected by the appropriation and use of water by agriculture and the altered water and salt balances that have been the result are one of the main characteristics of degraded lands. Chemicals being used in the environment are one of the most common causes of soil degradation today. The short- and long-term impact of these on people and soil organisms is well documented. When the life that herbicides take out disappears, the processes in the soil that enable it to hold water and resist erosion vanish.

Figure 1.3 Desertification processes in Marocco near Beni Boufrah. (a) shows the response to land degradation in the form of terraces built by an aid organisation which failed to work and triggered badlands. (b) was taken during an extreme event and it can be seen that most runoff is from paths. The farmers own terraces were effective (Credit: Anton Imeson 2011).

Most if not all of the earth's ecosystems show repeated evidence of land degradation in the past. This can easily be seen in the soil profile which provides an accurate record of past human actions, as is described in Chapters 4 and 5. This is illustrated in Figure 1.4 where mass movements of the deeply weathered soil profile have filled the valley bottom sediments. The rain forest was cleared for coffee production that resulted in land and soil degradation. Figures 1.5 and 1.6 from Bolivia are taken about 100 m apart above and below a surface into which badlands are developing and stripping the entire lacustrine deposit which is about 10 m thick. Figure 1.5 shows how sub surface flow is being triggered by the people who use the surface A2 horizon for bricks. This enables water to penetrate the erosive subsoil which disperses and is eroded creating the landscape down slope in Figure 1.6. Few soils today have escaped degradation and most have been totally changed by ploughing or grazing. That machines in the hands of man would endanger the environment was forecast by Pythagoras.

Figure 1.4 This photograph in the area of former Atlantic rain forest in Brazil was cleared to produce coffee until there was land degradation and erosion. Now it is used for ranching and it has low productivity. In places the Atlantic rain forest is being restored but mainly the land is used for Eucalyptus in which there is no wild life and it is a kind of green desert (Credit: Anton Imeson).

Figure 1.5 and Figure 1.6 are taken looking east and west. This lake deposit near Tarije Bolivia has its original A2 soil horizon that is being used for bricks. Human actions trigger subsurface water movement and lead to all of the lacustrine deposit being eroded until only bedrock remains. Nothing is left of the original amazing nature and wildlife that the first settlers encountered and when everyone could live from the land. Many functions that have gone include food, water and climate regulation. Most of the vegetation is exotic (Credit: Anton Imeson).

1.1.4 Restoring Land and Soil Functions Through Conservation, Protection and Restoration

Actions by people and societies enable them to adapt to desertification and restore land. Today soil conservation and protection are important because they can be a key tool in sustainable development. Some examples of this will be illustrated in Chapters 4, 5 and 6.

It has even been possible to stop and reverse or adapt to desertification by restoring different functions and this is demonstrated in many areas such as in Murcia Province in Spain and in the French Alps. There are many strategies and approaches to this that involve, for example, utilizing many different areas of administration and by the application of forestation, the regulation of financial markets, land tenure laws and responsibilities, and by promoting education and research. In many cases, however, if left unattended, many functions will restore themselves, as occurs on abandoned agricultural fields in different parts of the world. This is the case in Figure 1.7 taken on land that was recently used for wheat. By studying the development of the vegetation on agricultural fields abandoned for different lengths of time, it is possible to compare the changes in relation to time.

Figure 1.7 illustrates vegetation on abandoned agricultural fields near Mertola in Portugal. The land is colonized mainly by a species of Cistus and after about 12 years oak trees start to appear. The time since abandonment ranges from 2 years at the top left to 12 in the top right (Credit: Anton Imeson).

More than four thousand years ago in China, ways of reclaiming desertification-affected areas and of reducing flooding were developed and recorded. In Roman times, land use policy and loans created poverty and threatened food production to the extent that laws and regulations were introduced to prevent banks charging interest, which made people poor and unable to provide the food needed in Rome. Many successful afforestation projects were carried out throughout the world with great success during the nineteenth and twentieth centuries and afforestation is seen as one of the main strategies for combating desertification.

Soil conservation and protection throughout the ages has developed principles that can be applied with and by communities to restore much of what has been degraded. It can sometimes cause harm because of the economic pressure from mechanisms such as carbon subsidies. Trees are being planted in areas that are too arid or above the tree line in the paramo of South America, for example. Proper governance and organization are needed so that activities are managed. It also requires time, which can vary from a few years to centuries. In some situations, large improvements can occur in just a few years, so that areas that are seemingly hopelessly degraded can be transformed into areas valued for other products, hunting, nature or wine production. The value of terraces is both with respect to farming and flood protection. Figure 1.8a taken along the Yangze River shows the use of terraces both for agriculture and reducing sediment supply. Knowledge about the effectiveness of different kinds of terrace construction can be validated. It is not only in China that the value of terraces is understood, it is also in Europe at Cinque Terra. Figure 1.9a, where terraces became eroded when fields were abandoned and the maintenance stopped. In Figure 1.9b terraces are being reconstructed.

Figure 1.8a and Figure 1.8b The Chinese soil conservation service is implementing soil conservation works to prevent soil from entering the Yangtze River. The soil conservation service in China is experimenting with different techniques of terrace construction and erosion control that it applies in restoration work in much of the country (see Figure 1.8b) (Credit: Anton Imeson).

Figures 1.9a and 1.9b Restoring agricultural terraces at Cinque Terra, Italy, which has been possible because of the development of tourism and high added value products and services that exploit globalization (Credit: Anton Imeson).

1.1.5 Natural versus Man-Made Landscapes

Actual desertification is the desertification taking place today; historical desertification is that which occurred in the sometimes very distant past.

Many if not most of the phenomena of degraded land observed today were caused by erosion and land degradation that occurred in the past. During the last twelve thousand years (the Holocene) man has been the main geological agent. Today, actual land degradation processes follow a) forest clearances, b) farming practices, c) the over exploitation of resources, d) grazing, e) fire and f) pollution, as they also did in the past. Today's processes might be more extreme than historic ones because of tractors, bulldozers and chemicals and the lower resilience of the soil. They degrade the soil chemically, physically and biologically, making it sensitive to erosion and runoff production. On the other hand, past erosion has made the land less sensitive to erosion because the ground surface becomes armoured by stones and only the vegetation is adapted to this human impact. As far as runoff is concerned, the soil and land are different from the past but flood runoff will be much greater today. The causes of soil degradation and the solutions are common knowledge in many societies and cultures and these are explained in Part II of the book.

Actual or present-day geomorphological processes include those of erosion (by wind and water, on slopes and in river channels) and sediment transport. These can be directly responsible for accelerated erosion and flooding, when the vegetation and the protective soil organic layers have been changed by people. Bare soil or sand is valued aesthetically in some gardens in China and Japan. Figure 1.10 was taken during a storm in Osaka Japan that created urban runoff and erosion locally.

Figure 1.10 Soil erosion and runoff in a street in Osaka, Japan. In this cultural setting, erosion and soil degradation may have an aesthetic value in gardens (Credit: Anton Imeson).

Under relatively natural conditions, hydrological and geomorphological processes are regulated by the vegetation, ecosystem and soil, so that there is very little erosion, flooding and sediment transport. As a consequence of removing and modifying the natural system this regulation capacity can be reduced. The sensitivity of soil erosion to initial conditions means that it is hard to predict. On the other hand this is not always problem in practice because Figure 1.8 taken during rainfall along the Yangtze River shows the natural soil conservation function being performed by the forest and below it the function being provide by the farmer so that he can farm the slope. Both the trees and the farmer have the aim of using the soil as a resource and of keeping it on the slope.

Evidence of land degradation can obtained from monitoring or case studies from which changes can be quantified using key indicators of system behaviour (see Chapter 3). An indicator might be something as simple as the disappearance of rivers in Valencia, Spain or the loss of the topsoil that was once present beneath forests and which had a great capacity to retain water. This loss has occurred throughout the world with the spread of ploughing in Europe during the Middle Ages (Bork 2003).

Actual desertification can be established by recording and observing very many different desertification indicators. Desertification can be studied top down and this is the perspective of most international organizations and of remote sensing.

1.1.6 Dynamics of Human–Landscape Interactions

Human societal groups, whether farmers or stock raisers, are dynamic agents who are continually altering the natural landscape. The consequences include the loss of the existing landscapes with semi-natural ecosystems and their soil, plant and animal life. The loss involves the protection and regulation functions and their replacement with built-up areas and urban industrial wasteland. There is functional, structural and visual degradation of the remaining open landscape and its biological impoverishment and the ecological disruption of its natural ecosystems by accelerated erosion, soil, air and water pollution and neo-technological despoliation, combined with the creation of monoculture steppes. People are actively altering the local ecology so that in this sense there is a co-evolutionary process because the relationships that underpin the dynamics of the woodlands, fields and rivers are themselves evolving dynamically. These dynamic processes depend on the scale. Although these changes may be incorporated into our culture in urban environments, through organic architecture and planning, very often development is informal and unregulated.

The scale of desertification in which we are interested for a specific purpose is called the focal scale. This could be a single point in a field, a farm or slope, or a landscape or region. Coarse scale processes are those that are relatively slow such as changes in property law (Goldstein 2004) or the weathering of rock which can vary from tens to thousands of years. These constrain top down the ways in which desertification can progress and express itself. For example, in the Negev Desert researchers have shown how small differences in the nature of rocks influence the surface water holding properties of the soil. This can have a stronger influence on the degree of aridity than the amount of rainfall. Aridity and drought sensitivity can depend as much on rock type and weathering as on rainfall. This is one reason why aridity indices need to consider the properties of the land as well as the rain. They are a poor indicator of desertification. Marls lose much water from evaporation or runoff.

Both the physical and social environments constrain desertification. The geology, soil and geomorphology as well as the frontiers between cultures and customs form boundaries of what are regional or landscape scale desertification response units (DRUs). The sensitivity of an area to land degradation and desertification can therefore be delineated according to geology and culture.

Culture determines how resources are perceived and valued and determines how people act and the things they do.

At any focal scale we identify as being our concern, bottom up finer scale processes are those that drive change. They could be for example, things such as ploughing the soil or the interactions between the vegetation and soil that influence the infiltration and water holding capacity of the land. The feedbacks and interactions between man and the other actors that cause change is critical. This is beautifully illustrated in the recently published Atlas of Soil Biodiversity (2010) that explains the interactions between farming, soil biodiversity and desertification.

1.1.7 Land Use Changes

Land use changes are key to explaining desertification. This was the motivation behind the Medalus Project, supported by the European Union during which these relationships were measured and studied for more than a decade at target areas in southern Europe and elsewhere (Fantechi and Margaris 1986). It is not just the changes but rather the disregard for land capability or potential and the methods used which compact and degrade the soil structure. Figure 1.11a illustrates how badlands are being used for agriculture and Figure 1.11b illustrates how this is achieved.

Figures 1.11a and 1.11b are examples from Murcia, Spain, when bulldozed areas of badland soils sensitive to dispersion are cultivated. Such areas erode after the first rainfall and are not suitable as building land nor really for agriculture because of their salt and very high carbonate content (Credit: Anton Imeson).

In most parts of the world, there are many areas where areas that were once cleared for agriculture are now forested again (Bork 2003). This is illustrated by New York state and New England, Germany and in the Belgian Ardennes as well as in Spain, Greece and Italy. The soils and forest found today contrast greatly with those from the past. At the local scale, human actions can either bring about land degradation or they can reverse it. For example, if fine scale processes in the soil are promoted so that its water and nutrient regulating characteristics are improved, it can hold much more water and its temperature regime will become more moderate. Emergent higher level benefits will follow, such as higher crop yields, less runoff and flooding, more infiltration and groundwater for irrigation and more and clean water for urban areas. Farmers can prevent soil degradation and enhance soil functions.

The land is just like the ocean. In most seas around Europe desert-like conditions have been caused by fishing; the effects of fishing for shellfish and shrimps is particularly damaging to the biodiversity. But where the sea bottom is not dragged and disturbed for cockles, shrimps, within a few years in marine reserves there can be a remarkable recovery of the life on the sea bed. The same is true on land. When this is left alone and people stay away, after a few years there can be a dramatic improvement in life and biodiversity. The best thing we can do after a forest fire is usually nothing (Cerda 2010).

What is meant by sustainable land management is land management that produces the second situation whereby actions are taken that makes things improve. In practice this means prioritizing the soil and water conservation as the function rather than the crops that it can produce. It has more value. The effectiveness of traditional farming systems in combating desertification and guaranteeing food security is significant. These systems are those in which people's actions in combination with natural processes sustain the functioning of the soil and land.

The current degraded state of world is therefore an expression of man's cumulative impact during the Holocene Period. A relevant question then is can we ignore this and does it matter? The long-term carrying capacity and collapse of the earth's ecosystems might be occurring because of the depletion of life in the oceans and on land. Biologists focus on the biodiversity as an indicator of this. However, the response then is perhaps to have a policy that targets protected areas, endangered species and nature reserves rather than the entire area.

More than half of the world's productive capacity is now being appropriated by humans for food and raw materials as well as 85 per cent of the world's water. Charles Darwin in 1834, Thomas Huxley in 1885 and Malthus in 1888 as well as Heidegger in 1935 and Leopold in 1949 were amongst the many who realized that this would inevitably result in the degradation of what they saw as the capital provided by nature for man. They thought that the growth in the human population would exceed the earth's carrying capacity (considered to have been reached in 2010). Diamond (2005) explained many examples where the collapse of civilizations were a consequence of ignoring land degradation.

1.1.8 Thresholds and Different States

Desertification sometimes occurs when critical conditions are reached and the system changes into a different state. Research by systems ecologists and earth scientists have identified thresholds whereby there is a change in some condition (trigger) that leads to the system moving to a different state: in this case, from one in which there is the experience of an attractive and a not desertified existence into one that is degraded. One example is a land or soil system that suddenly loses its capacity to store water so that plants cannot live and erosion and runoff occur very frequently instead of never. Another example illustrated in Figure 1.15 is when groundwater tables are lowered and spring discharge and seepage decrease.

This idea can be easily visualized and understood by observing the soil under a plant in a garden or park and comparing what is found on bare areas and under the shrubs in the shade. Under the shrub or plant the soil is shaded and relatively cool in the summer or warm in winter but in the open it is compact because of the impact of rainfall and the lack of strength because there are no roots or substances that bind it together. In the garden it is easy to practise transforming our soil into a desert-like system or into one that is abundant with life.

A frequent consequence of the over exploitation of an area is that the landscape loses its capacity to function as a provider of clean and adequate water and protector from erosion, landslides and flooding. The system can change into another state in which processes that may be thought of as indicating the presence of natural capital, resilience, ecosystem services and complexity, are lost. The land and soil can no longer store water and retain plant nutrients. Positive feedbacks cause a progressive loss of plant cover and biodiversity and the soil becomes thinner with more frequent heat and water extremes. It can become affected by soil degradation, salinity and erosion processes. Some processes are slow, occurring across the lifetimes of several generations, and other are more or less instantaneous. They act together to trigger hazards, such as flash floods and landslides. For example, the flooding in Pakistan in August 2010 is not just the result of the Monsoon but of the land and soil degradation, causing increasingly higher amounts of runoff and at the same time reducing the capacity of the river channels with sediment eroded from the land. This process can be seen to be taking place wherever people have to cope with the floods produced by development and forest clearance, as on Caribbean islands, where rainfall is frequently highly intense. The River in Figure 1.15 suddenly lost about 80 percent of its flow because of the permits given for developers to pump water for new orange plantations. The people in the village using the water for generations had not legal protection, so what was a river fed by powerful limestone springs is transformed into an open drain.

1.1.9 Feedbacks and Control

There is no effective feedback or process that links this knowledge to the actions that society and governments take at the global scale or in most countries on a national scale. And even if this knowledge is present it does not stop a process in which the benefits are money and jobs. Never-the-less as the case from Dutch South Limburg illustrated in Figures 1.12 to 1.14 illustrates as a response to flooding in the villages, research was carried out to identify farming techniques that would prevent runoff and erosion. Figure 1.13 shows the experiments (set up by Frans Kwaad) during winter rainfall. This and other research were applied and further erosion and flooding largely stopped. The landscape before (Figure 1.12) and after land consolidation (Figure 1.14) is illustrated. This can be achieved by a soil conservation service that is functioning such as on the Cape Verde Islands. Figure 1.16 and Figure 1.17 illustrate the terraces in the Cape Verde Islands that enable the people to cultivate very steep slopes. Soil conservation is a response to the erosion and famines that occurred in the quite recent past. Without appropriate governance the situation will repeat itself and continue as there is no moral or cultural imperative that restrain actions.

Figure 1.12, 1.13 and 1.14 show Limburg, The Netherlands, where land consolidation and farming caused many problems with erosion and flooding. The old landscape is shown in Figure 1.12 (Credit: Anton Imeson and Luuk Dorren). Research into ways of reducing erosion (Figure 1.13) resulted in regulations that have been applied and now limit erosion (Credit: Anton Imeson). Figure 1.14 shows that a large amount of loess has been lost and the underlying chalk or less fertile sediments are at or near the surface, reducing the productive function of the soil (Credit: Luuk Dorren). (Ransdalerveld, South Limburg (NL), April 2003. From Dorren.)

Figure 1.15 The Riu del Sants River in Canals which has provided the Town with water for hundreds of years and to which the town owes its existence has recently had its discharge reduced to a fraction because of the abstraction of groundwater for new orange plantations (Credit: Anton Imeson).

Figure 1.16 and Figure 1.17 Cape Verde Islands. The Cape Verde Islands has an effective soil conservation service that is helping farmers in response to and as feedback from disasters caused by soil loss and famine in the recent past (Source: Figure 1.17 Anton Imeson).

In many developed countries, floods are responded to seriously because they directly threaten life and property. However, climate change is explained as the most common cause and the only feasible option, the improvement of the river channel capacity to convey more flood runoff. Restoring the soil and water protection of the land can be done. This would require the farmers and landowners restoring the soil structure and water capacity so that the soil could retain maybe 60 centimetres of rainfall as it once did instead of the few millimetres that is often the case today. This might cost less than the insurance paid to people on the floodplains who think that they are being flooded by rainfall and are not aware that it is runoff. In some places where rivers were on average 100 m wide, they may be now only 10 m wide because of ground water abstraction. At the same time the runoff coefficient (proportion of rainfall that reaches the river) is far higher and new sources of flood runoff have been created on agricultural and built-up lands to which rivers are not adjusted.