Copyright © 2003 Swets & Zeitlinger B.V., Lisse, The
Netherlands
PROCEEDINGS OF AN INTERNATIONAL CONFERENCE, DUBAI, 12–15 FEBRUARY
2000
Desertification in the Third Millennium
Edited by:
Abdulrahman S. Alsharhan United Arab Emirates University, Al-Ain,
United Arab Emirates E-mail:
[email protected]
Warren W. Wood U.S. Geological Survey, Reston, Virginia, USA
E-mail:
[email protected]
Andrew S. Goudie University of Oxford, Oxford, United Kingdom
E-mail:
[email protected]
Abdulrahman Fowler United Arab Emirates University, Al-Ain, United
Arab Emirates E-mail:
[email protected]
Eissa M Abdellatif Zayed International Prize for the Environment,
Dubai, United Arab Emirates E-mail:
[email protected]
A.A. BALKEMA PUBLISHERS LISSE / ABINGDON / EXTON (PA) / TOKYO
Copyright © 2003 Swets & Zeitlinger B.V., Lisse, The
Netherlands
Copyright © 2003 Swets & Zeitlinger B.V., Lisse, The
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Published by: A.A. Balkema Publishers, a member of Swets &
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ISBN 90 5809 571 1
Copyright © 2003 Swets & Zeitlinger B.V., Lisse, The
Netherlands
PART 1. Desertification and Global Climatic Change
David S.G. Thomas Into the Third Millennium: The Role of
Stakeholder Groups in Reducing Desertification . . . . . . . . . .
. . . . . . . . . . . . . 3
Andrew S. Goudie The Impacts of Global Warming on the Geomorphology
of Arid Lands . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . 13
Victor R. Squires Desertification, Climate Change and the World’s
Drylands . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . 21
Shaw-Wen Sheen, George A. Brook, Bruce L. Railsback and Jean C.
Thill Stalagmite Annual Layer Thickness as a Proxy for Enso and
Rainfall: Evidence from Drotsky’s Cave, Botswana . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . 27
Christopher G.ST.C. Kendall, Paul Lake, Dalton H. Weathers III,
Venkat Lakshmi, John Althausen and Abdulrahman S. Alsharhan
Evidence of Rain Shadow in the Geologic Record: Repeated Evaporite
Accumulation at Extensional and Compressional Plate Margins . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
45
Stephen Stokes, Andrew S. Goudie, Alison Colls and Asma Al-Farraj
Optical Dating as a Tool for Studying Dune Reactivation, Accretion
Rates and Desertification Over Decadal, Centennial and Millennial
Time-Scales . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . 53
Venkat Lakshmi, Christopher G.ST.C. Kendall, John Althausen and
Abdulrahman S. Alsharhan Studies of Local Climate Change in United
Arab Emirates Using Satellite Data . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . 61
Walid A. Abderrahman and Ibrahim M. Al-Harazin The Impacts of
Global Climatic Change on Reference Crop Evapotranspiration,
Irrigation Water Demands, Soil Salinity, and Desertification in
Arabian Peninsula . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . 67
Adrian M. Harvey The Response of Dry-region Alluvial Fans to
Quaternary Climatic Change . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . 75
Christopher G.ST.C. Kendall, Venkat Lakshmi, John Althausen and
Abdulrahman S. Alsharhan Changes in Microclimate Tracked by the
Evolving Vegetation Cover of the Holocene Beach Ridges of the
United Arab Emirates . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . 91
Daryoush Mehrshahi, David S.G. Thomas and Sarah O’Hara Late
Quaternary Palaeoenvironmental Changes, Ardakan Kavir (Playa),
Central Iran . . . . . . . . . . . . . . . . . . . . . . . . . .
99
Werner Smykatz-Kloss, Bernd Roscher and Konard Rögner Pleistocene
Lakes in Central Sinai, Egypt . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . 111
Ronald J. Spencer, Wenbo Yang, Sheila M. Roberts and H. Roy Krouse
Hydrology and Climate Change (200 to 100 ka), Death Valley,
California, USA . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . 117
Desertification in the Third Millennium. Edited by A.S. Alsharhan,
W.W. Wood, A.S. Goudie, A. Fowler and E.M. Abdellatif. © 2003 Swets
& Zeitlinger Publishers, Lisse, The Netherlands, ISBN 90 5809
571 1, p. V–VIII.
Copyright © 2003 Swets & Zeitlinger B.V., Lisse, The
Netherlands
VI
Navin Juyal, Amal Kar, S.N. Rajaguru and A.K. Singvi
Chronostratigraphic Evidence for Episodes of Desertification since
the Last Glacial Epoch in the Southern Margin of Thar Desert, India
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . 123
PART 2. Biodiversity, Mangroves and other Halophytes and their
Conservation Ecosystems
John M. Peacock, Ghalib A. Alhadrami, M.E. Ferguson, R. Karnik, Ian
R. McCann and Ali Saleh Desert Forages of the Arabian Peninsula –
The Conservation and Utilization of Biodiversity for Sustainable
Animal Production in the United Arab Emirates . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . 131
Ahmed S. Khalil, Urlich Saint-Paul and Eisa M. Abdellatif Response
of Meiofauna to Mangrove Degradation in a Dry Semi-Desert Coastal
Habitat of the Red Sea (Sudan) . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . 139
J.C. Dagar Biodiversity of Indian Saline Habitats and Management
& Utilization of High Salinity Tolerant Plants with Industrial
Application for Rehabilitation of Saline Areas . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
151
Fatima Al-Ansari and Ali A. El-Keblawy An Analysis of Biodiversity
of the United Arab Emirates Flora Using Western’s Flora . . . . . .
. . . . . . . . . . . . . . . . . . 173
Ghalib A. Alhadrami, Abdullah J. Al-Dakheel, Mahmoud M. Khorshid,
Saleh A. Al-Sharaby and Mohamed H. Abdel Gawad Feeding Camels and
Sheep Sporobolus Grass Grown in Saline Desert Lands in the United
Arab Emirates . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
183
Abdullah A. Jaradat Halophytes for Sustainable Biosaline Farming
Systems in the Middle East . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . 187
Vishnu P. Singh Biodiversity, Community Pattern and Status of
Indian Mangroves . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . 205
Ali A. El-Keblawy Effects of Protection from Grazing on Species
Diversity, Abundance and Productivity in Two Regions of Abu Dhabi,
United Arab Emirates . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . 217
Muhammad Asif Khan and Nasser A. Al-Homaid Remote Sensing Study on
Mangrove Depletion Tarut Bay, Saudi Arabia . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . 227
PART 3. The Effect of Wind and Water on Soil Erosion and Sand
Creep
Hans-Jörg Barth Late Holocene Sedimentation Processes Along the
Arabian Gulf Coast in the Jubail Area, Saudi Arabia . . . .
237
Belnap Jayne, Sue Phillips, Mike Duniway and Rich Reynolds Soil
Fertility in Deserts: A Review on the Influence of Biological Soil
Crusts and the Effect of Soil Surface Disturbance on Nutrient
Inputs and Losses . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
245
Larry Boersma and J. Baham Aspects of the Role of Biogeochemical
Processes in Soils in the Global Carbon Cycle . . . . . . . . . . .
. . . . . . . . . . . . 253
Copyright © 2003 Swets & Zeitlinger B.V., Lisse, The
Netherlands
VII
Yann Callot Relations Between Wind Data and Geomorphology in
Aeolian Sand Geodynamics . . . . . . . . . . . . . . . . . . . . .
. . . . . . 263
Richard Reynolds, Marith Reheis, Pat Chavez, Jr., Todd Hinkley,
Richard Tigges, Gary Clow, David MacKinnon, Paul Lamothe, Nicholas
Lancaster, Mark Miller, James Yount, Miguel Velasco, Stuart Sides,
Deborah Soltesz, Greg Meeker, Robert Fulton and Jayne Belnap Dust
Emission and Deposition in the Southwestern United States –
Integrated Field, Remote Sensing, and Modeling Studies to Evaluate
Response to Climatic Variability and Land Use . . . . . . . . . . .
. . . . . . . 271
Robert H. Webb and Kathryn A. Thomas Recoverability of Severely
Disturbed Soils and Vegetation in the Mojave Desert, California,
USA . . . . . . . . . . . 283
Giles F.S. Wiggs, Sarah L. O’Hara and B.K. Mamedov Wind Erosion and
Dust Deposition in the Aral Sea Region: Possible Consequences of
Unsustainable Human Activity . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . 291
Jasem M. Al-Awadhi, Ali Al-Dousari and Abdullah Al-Enezi Barchan
Dunes in Northern Kuwait . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . 299
Saleh Al-Muzaini Environmental Measures to Control Sand Movement in
Kuwait . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . 309
PART 4. Land Degradation and Management in Arid, Semi-Arid and Dry
Sub-Humid Areas
William R. Stanley Herero, German and Afrikaner in Arid and
Semi-Arid Eastern Namibia: Comparative Technologies for Water Use
and Conservation . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . 317
Ruth Schofield Soil Salinity as a Degradation Process in Spain and
Tunisia . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . 327
Migdam E. Abdelgani, A.G. Osman and S.S. Mohamed Restoring Soil
Fertility of Desertified Lands Through Biological Nitrogen Fixation
in Sudan . . . . . . . . . . . . . . . . 335
Khaled R. Ben-Mahmoud, Shaban Mansur and A. Al-Gomati Land
Degradation and Desertification in Libya . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . 339
Shabbir A. Shahid, Samira A.S. Omar, Raafat Misak and H. Abo Rizq
Land Resource Stresses and Degradation in the Arid Environment of
Kuwait: An Overview . . . . . . . . . . . . . . . . . 351
Elnur Abdalla Elsiddig Management of Dry Land Forest Reserves in
Sudan Based on Participatory Approach . . . . . . . . . . . . . . .
. . . . . . . . 361
Banaras Hussain Niazi and Jelte Rozema Introduction of
Non-conventional Salt Tolerant Crops Under Salt Affected Arable
Land in Pakistan . . . . . . . . . 365
PART 5. Policies and Cost/Benefit for Combating Land Degradation
and Desertification
Fouad Kanbour The International Convention on Desertification: the
Preservation of Indigenous Technologies in Arab Countries of West
Asia . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . 375
Scott Christiansen Lessons from Rural Development of Relevance to
Desertification . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . 381
Copyright © 2003 Swets & Zeitlinger B.V., Lisse, The
Netherlands
VIII
Adel El-Beltagy Sustainable Management of Rangelands and
Agricultural Systems of the Drylands: The ICARDA Experience in
Combating Desertification . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . 389
Ahmed A.R. Elagib Can Science and Technology Help to Initiate
Natural Regreening of the Arabian Peninusula? . . . . . . . . . . .
. . . . . 399
Mahlagha Ghorbanli and A. Motamed The Desert Environment in Iran .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . 407
PART 6. Application of Remote Sensing and Geographic Information
System (GIS) to Study Desertification
John D. Althausen, Jr., Christopher G.ST.C. Kendall, Venkat
Lakshmi, Abdulrahman S. Alsharhan and Gregory L. Whittle Using
Satellite Imagery and GIS in the Mapping of Coastal Landscapes in
an Arid Environment: Khor Al Bazam, Western Abu Dhabi, United Arab
Emirates . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . 415
Zeinelabidin S. Rizk and Abdulrahman S. Alsharhan Geographical
Information System Modeling of Groundwater Potentiality in the
Northeastern Part of the United Arab Emirates . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . 423
Andy Y. Kwarteng, Raafat F. Misak and Mohammed A. Al-Sudairawi
Radarsat Synthetic Aperture Radar (SAR) Imagery Observation of Sand
Dunes in Kuwait . . . . . . . . . . . . . . . . . . . 435
Osman Mirghani Mohamed Ali and El Tayeb Osman Adam Application of
Remote Sensing for the Assessment of Environmental Changes in
Western Kordofan State (Sudan) . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . 445
Mansouri Taoufik, Boussema M. Rached, Albergel Jean and Chaibi
Najeh Application of Remote Sensing and GIS to Study Erosion in
Tunisia . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . 453
Ibrahim S. Ibrahim, M.M. Ahmed, M.A. Mustafa and Mustafa A. El Hag
Preliminary Study of Sand Erosion in South Khartoum Area, Sudan . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . 461
PART 7. Groundwater Resources in Desert Areas
Mohammed Saqar Al Asam Groundwater Situation in the United Arab
Emirates: An Overview . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . 469
Mohammed Rasheeduddin, W.A. Abderrahman and John W. Lloyd
Sustainable Development of a Depletable Aquifer: A Case Study . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . 477
Khaled Hadi and M. Al-Senafy Suitability of Groundwater for
Irrigation in Kuwait . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . 487
Copyright © 2003 Swets & Zeitlinger B.V., Lisse, The
Netherlands
Preface
The Desertification Conference entitled “Toward Better Management
of Arid and Semi-Arid Lands in the Twenty-First Century” was
convened in Dubai, UAE, during 12–16 February 2000, under the
auspices of the Zayed International Prize for the Environment. This
volume contains a representative selection of 53 of the original
125 oral presentations at the conference, which contributed to the
following objectives:
• to enhance our understanding of local, regional, and global short
and long-term environmental changes; • to convey best practices
associated with the ecological management of arid areas; and • to
improve our general understanding of desert environments as we are
approaching the third millennium.
The papers are distributed among the following themes:
1. Desertification and global climatic change 2. Biodiversity in
mangrove and halophyte ecosystems 3. The effect of wind and water
on soil erosion and sand creep 4. Land degradation and management
in arid, semi-arid, and dry sub-humid areas 5. Policies and
cost/benefits for combating land degradation and desertification 6.
Application of remote sensing and Geographic Information System
(GIS) to desertification studies 7. Groundwater resources in desert
areas
Desertification is land degradation in dry land environments
resulting from such factors as climatic variation and human
activities. It is the outcome of the interactions between human
land-use practices and a dynamic, uncertain environment. If global
warming predictions are realized, the environments of desert areas
and their margins are likely to be profoundly affected. Global
warming may lead to changes in soil moisture availability following
changes in both precipitation and evapotranspiration rates caused
by the temperature rise itself. The global climate is ever
changing, however, global warming does not result in every point on
the surface of the earth experiencing an increase in surface
temperature. There is a need to study climate on local spatial
scales in order to understand its variability in time. This change
is an integrated effect of natural climate variability and
human-induced changes. Protection and habitat preservation
initiatives offer the best solutions for biodiversity conservation
in the face of desertifi- cation and loss of rangelands to
agriculture. Both dryland and wetland reserves have provides
effective protection for rare, endangered, and endemic species.
Mangroves are one of the dominant features of the shores of
tropical coun- tries. Ecologically, they have been considered an
important component of coastal ecosystems. Biodiversity and the
mangrove ecosystem are closely related to diversity of coastal
bio-climatic, geological and sociological con- ditions; frequency
of inundation; circulation pattern; and water quality of coastal
areas. Land degradation, deser- tification, and deforestation are
considered to be major environmental problems in many countries of
the world. The major causes for desertification were recognized as
natural environmental factors and manmade causes. Unsustainable
irrigation practices, overgrazing, uncontrolled cultivation,
wood-gathering for fuel, salinization, and water logging are cited
as the main activities that contribute to the degradation of land
area in the region.
The Dubai International Conference on Desertification has focused
on an issue that affects most of the world’s population, directly
or indirectly. It is of paramount importance in the Middle East,
Africa, Asia, Australia, and America and is closely tied to the
vicious cycle of poverty and environmental deterioration.
The Zayed International Prize for the Environment fully sponsored
and organized this conference. This Prize is a non-profit
organization aiming to promote and encourage outstanding and
pioneering environmental achieve- ments in line with the
environment and development vision and philosophy of the dedicated
environmentalist, H.H. Sheikh Zayed Bin Sultan Al Nahyan, President
of the United Arab Emirates.
Founded by General H.H. Sheikh Mohamed Bin Rashid Al Maktoum, Crown
Prince of Dubai and UAE Defense Minister, the Zayed International
Prize for the Environment, is more than a prize – it is a
foundation which endeavors to promote sustainable development
through various environmental initiatives. In addition to adminis-
tering the prestigious Prize of one million dollars, this
foundation also organizes regional and international con- ferences
and forums on specific environmental issues; publishes a magazine,
a book series, and a newsletter; and
Desertification in the Third Millennium. Edited by A.S. Alsharhan,
W.W. Wood, A.S. Goudie, A. Fowler and E.M. Abdellatif. © 2003 Swets
& Zeitlinger Publishers, Lisse, The Netherlands, ISBN 90 5809
571 1, p. IX–X.
Copyright © 2003 Swets & Zeitlinger B.V., Lisse, The
Netherlands
X
helps raise environmental awareness through public lectures,
training seminars, workshops, and the development of relevant
information materials.
The Zayed Prize for the Environment will be awarded to individuals
and organizations that have:
• successfully solved a specific environmental problem; • advanced
the cause of the environment toward sustainable development; •
brought to public notice significant environmental issues or
mobilized action toward their solution; • contributed significantly
to intellectual, scientific, or theoretical approaches to
environmental concerns; and/or • undertaken activities and
initiatives which can serve as a model to others.
For information and submission guide it is recommended to refer to
the website: www.zayedprize.org
The Editors A.S. ALSHARHAN, W.W. WOOD, A.S. GOUDIE, A. FOWLER, and
E.M. ABDELLATIF
Copyright © 2003 Swets & Zeitlinger B.V., Lisse, The
Netherlands
The Dubai International Conference on Desertification was the first
international event of the Zayed Prize Foundation. The members of
the Organizing and Scientific Committees of the conference express
their sincere gratitude and thanks to the General H.H. Sheikh
Mohamed Bin Rashid Al Maktoum, Crown Prince of Dubai, UAE Defense
Minister, Patron of the Zayed International Prize for the
Environment and Patron of the Conference, for his unceasing support
and inspiration that made this event a great success.
We would like to thank H.H. Sheikh Nahyan Mubarak Al Nahyan,
Minister of Higher Education and Scientific Research and Chancellor
of the United Arab Emirates University for his inspiration,
encouragement and support.
Special thanks go to the United Arab Emirates University for
helping in the organization and follow up, and to the Dubai Police
General H.Q. for their unlimited support in terms of facilities and
human resources. The Dubai Police sub-committees were very
instrumental in making sure that everything ran smoothly and
systematically. The UAE Radio & TV Corporation in Dubai did a
great job in promoting and covering the conference. The UNDP office
in Abu Dhabi was instrumental in distributing the message via the
UNDP offices all over the world. The UNEP played a major role in
the coordination and opening of the conference together with the
UNCCD Secretariat. We also thank the United States Geological
Survey for their support of the Scientific Organization
Committee.
Sincere appreciation is also extended to all the sponsors who
contributed to the conference and/or participated in the exhibition
to make it a success; especially the UAE Post, Emirates Airlines,
BMW, National Bank of Dubai, DUBAL, Gulf Eternit, Dubai
Municipality, Dubai Electricity & Water Authority, UAE Federal
Environmental Agency, and the UAE Ministry of Agriculture &
Fisheries.
Our sincere appreciation goes to all the authors of this proceeding
for their efforts in writing and revising their manuscripts to meet
our deadlines and the publisher’s standard.
The authors of this book would like to thank Dr. Mohamed Ahmed Bin
Fahad, Chairman of the Higher Committee of the Zayed International
Prize for the Environment, for his inspiration and encouragement.
Without his support, this publication would not have been
possible.
We greatly appreciate the effort of Mr. Mohamed Shahid who assisted
us in more ways than could be imagined. He processed the chapters
for this volume from inception to final completion, incorporated
the authors’changes, and handled all correspondences with the
authors. We would also like to express our thanks to Mr. Hamdi
Kandil for drafting all the figures, arranging them in proper
position in this book, and producing the final camera-ready copy of
this volume.
We thank Balkema Publishers for their patience and encouragement
from the inception of this book to its completion.
We dedicate this publication to General H.H. Sheikh Mohamed Bin
Rashid Al Maktoum, Crown Prince of Dubai, UAE Minister of Defense,
and Patron of the Zayed International Prize for the
Environment.
Desertification in the Third Millennium. Edited by A.S. Alsharhan,
W.W. Wood, A.S. Goudie, A. Fowler and E.M. Abdellatif. © 2003 Swets
& Zeitlinger Publishers, Lisse, The Netherlands, ISBN 90 5809
571 1, p. XI.
Copyright © 2003 Swets & Zeitlinger B.V., Lisse, The
Netherlands
PART 1
Copyright © 2003 Swets & Zeitlinger B.V., Lisse, The
Netherlands
INTRODUCTION
The interactions between people and the environment are, at the
beginning of the 21st century, more compli- cated, intense and
extensive than ever before (e.g. Babaev, 1999). Land degradation,
of which desertifi- cation is the component within the world’s
drylands, has been suggested to be the most pressing of current
environmental problems (Stocking, 1995). Some authorities, such as
Williams and Balling (1995), have presented desertification as the
outcome of late 20th century population growth, resulting in
increased human pressures on marginal dryland environments. The
growth in significance of desertification is there- fore one of
many steps of human pressure on the envi- ronment that have
occurred and continue to occur during the Holocene period, as both
population num- bers and the ways in which societies can use the
phys- ical environment have increased.
Desertification, even if viewed as a subset of the gen- eral land
degradation problem, has undoubtedly proved to be controversial,
especially in the period since the 1977 United Nations Conference
on Desertification (UNCOD) (see Thomas and Middleton, 1994; Stiles,
1995). The term has been seen as confusing, by lumping together a
range of environmental processes (e.g. Barraclough, 1995) and
because of the images it pres- ents, as misleading, and therefore
redundant (e.g. Mainguet, 1991), as it conjures up inappropriate
images of desert advance through sand dunes encroaching upon
productive land (a process that might occur in a very small number
of limited instances, but which certainly is not the universal face
of desertification). Even with more appropriate recognition of the
insidious nature
of desertification in most instances, an agreed defini- tion,
consensus about the scale of the problem and an acceptance of the
most appropriate ways to tackle it, have been difficult to achieve.
We can however be fairly certain that the term and phenomena are
here to stay, particularly as in 1994, after intensive and complex
discussions the UN general assembly approved the Convention to
Combat Desertification (CCD).
Desertification is therefore a much-discussed envi- ronmental, and
social, problem, and one that scientists, politicians,
non-government organisations (NGOs) and even environmental
journalists have held strong views about. The CCD has been ratified
both by the governments of “affected country parties”, those coun-
tries that experience desertification, and by “developed country
parties”. These groups are in theory not mutu- ally exclusive,
since developed world countries with dryland areas can be, and are,
affected by desertifica- tion, for example in the case of European
Union states bordering the Mediterranean basin, but this categori-
sation does hint towards a polarisation of the states of the North
(which can be donors) and the South (which can receive financial
assistance under the Convention). November 2002, 184 countries had
ratified, accepted to the convention. This includes many countries
form the South, including those experiencing desertifi- cation, and
many countries from the North who are potential sources of
expertise and finance for anti- desertification activities. A
number of countries that were initially reluctant to recognize the
convention, including some with extensive dryland areas, have now
done so. Notable in this respect are the USA (ratification in
February 2001) and Australia (August 2000).
Into the Third Millennium: The Role of Stakeholder Groups in
Reducing Desertification
D.S.G. THOMAS Sheffield Centre for International Drylands Research,
Department of Geography, University of Sheffield, Sheffield,
UK
ABSTRACT: Desertification, or land degradation in drylands, is the
outcome of the interactions between human land-use activities and a
dynamic, uncertain environment. Desertification is not a new
problem but, since its for- malisation in 1977 at United Nations
Conference on Desertification, has been a controversial one.
Drawing prin- cipally upon the African desertification context, the
paper considers the factors that have contributed to the
controversial nature of desertification and the issues associated
with four stakeholder groups: politicians, scien- tists, local
people and NGOs, in anti-desertification activities. Each of these
groups is given a role within the UN’s 1994 Convention to Combat
Desertification, and while all are significant within
anti-desertification activi- ties, it is argued that their relative
positions have fluctuated in the period since United Nations
Conference on Desertification.
Desertification in the Third Millennium. Edited by A.S. Alsharhan,
W.W. Wood, A.S. Goudie, A. Fowler and E.M. Abdellatif. © 2003 Swets
& Zeitlinger Publishers, Lisse, The Netherlands, ISBN 90 5809
571 1, p. 3–12.
Copyright © 2003 Swets & Zeitlinger B.V., Lisse, The
Netherlands
The CCD represents a key stage in the long, tortuous, relationship
between the United Nations and desertifi- cation. The relationship
commenced formally in 1977 with UNCOD, but less formally, UN
agencies such as the FAO and UNESCO had been investigating and
inter- preting environmental problems in drylands since the 1950s.
For example, Meig’s (1953) much-cited defini- tion of arid
environments was published in UNESCO’s Arid Zone Research Series.
The CCD has been seen as a sustainable development strategy, since
it embodies economic, social and environmental needs and issues
(Chasek, 1997). The process leading to the drafting of the CCD and
its subsequent ratification are well described by Corell (1999),
and involved the repre- sentatives of national governments,
representatives of 187 different NGOS from around the world, and a
17-strong International Panel of Experts on Desertifi- cation
(IPED), representing a range of science and social-science
disciplines. The negotiation of, and preparation for, the CCD
arguably provided avenues for inputs from local (via NGOs) to
national levels, and from traditional and “expert” (via IPED)
sources. The CCD also recognises the roles of a range of action
lev- els, from international to “bottom-up” in countering the
desertification problem.
It is not the purpose of this paper to specifically con- sider the
contributions and relative responsibilities of different groups of
actors in the CCD, however; this has been done in detail by Corell
(1999). The CCD is just one component of the desertification issue,
and its impact and effectiveness are not yet clear. Rather, this
paper sets out to provide a qualitative assessment of the relative
roles of four key actor groups: politicians, NGOs, local peoples
and scientists, in the issues and controversies that have
surrounded desertification and in the attempts to counter land
degradation in drylands.
DESERTIFICATION CONTROVERSIES
There are a number of reasons that can be identified as sources of
the confusion and controversies that have surrounded
desertification, especially in the past 20 or so years. Recognising
these factors provides a useful background to the consideration of
the roles of different groups of people in the desertification
debate. Four important factors are considered below.
Issue clarity and images
With over one hundred published definitions (Glantz and Orlovsky,
1983), desertification has been inter- preted as both an
environmental process and as a state of the environment. Many of
the published definitions
treat desertification as a collective term for environment-
degrading processes that are enhanced by both direct and indirect
anthropogenic actions. Differences between definitions frequently
occur in the detail, for example in terms of whether changes in
vegetation systems, which may be readily reversible, are of the
same status as changes in the soil system that, once eroded or
salinized, may represent an almost perma- nent negative change of
condition (see Thomas and Middleton, 1994 for discussion). These
details however have significant implications for how
desertification is assessed, monitored and addressed.
In the CCD desertification is defined as land degra- dation in
arid, semiarid and dry subhumid areas result- ing from various
factors including climatic variation and human activities. In this
definition land includes soil, vegetation and groundwater
resources. This defi- nition is in fact modified from an earlier UN
version (UN, 1992) that stated only human actions as the causal
mechanism. The broadening of the definition represents in part a
political and scientific compromise (to remove “the blame” solely
from human actions, to include “acts of god” for which people, and
politicians, cannot be held responsible) and scientific pragmatism
(human actions can themselves modify climate, thereby pro- viding
an indirect human impact on desertification. While the focus on
drylands may seem obvious for an issue called desertification, it
has not always been the case, with the term being more widely
implied in some quarters, especially in the post UNCOD-period, to
include environments far away from dryland areas, for example
Denmark (in Fantechi and Margaris, 1986). As Warren and Agnew
(1987) note, a broad definition has a tendency to deprive the term
of diagnostic value.
The relationship between desertification, which relates to land
degradation, and drought, a natural cli- matic phenomenon, has also
lacked clarity. The two issues appear to have been intermingled
from the out- set of preparations for UNCOD, since it was the
social impacts of the 1970s Sahel drought that triggered demands
for an international conference on desertifi- cation (Thomas and
Middleton, 1994; Corell, 1999). Drought is an intrinsic component
of dryland areas (e.g. Agnew and Anderson, 1992), and it is indis-
putable that drylands are very susceptible to drought. From a human
dimension, drought is something that has to be copied with, or
avoided. Nomadism and struc- tured human mobility are
drought-coping strategies that have been effected by dryland
populations for centuries. Both however are increasingly denied by
the sedentary social structures imposed by growing absolute
population sizes, and by patterns of land use change and allocation
that inhibit of expressly exclude traditional migration patterns
(e.g. Sporton et al., 1999). Consequently, dryland populations are
perhaps more vulnerable to drought today than at any time in
D.S.G. THOMAS
Copyright © 2003 Swets & Zeitlinger B.V., Lisse, The
Netherlands
the past. Coping with drought however is a different matter to
coping with, or reducing, desertification (e.g. Kemp, 1990; Warren
and Khogali, 1992), and should not be confused. The former may
require relatively short-term aid or external food support, the
latter requires a structured, long term effort to halt and then
reverse the processes of land degradation.
Lack of scientific understanding about dryland environments
Dryland areas, ranging from dry subhumid regions to the “true”
hyperarid deserts, cover 47% of the earth’s land surface (Hulme,
1996; Middleton and Thomas, 1997). The scientific understanding,
and knowledge of, dryland environmental systems is relatively poor
(Warren et al., 1996) lagging behind the understanding of temperate
environments and even of unpopulated polar regions. Many reasons
account for this, but two of significance can be noted. First, for
some branches of the environmental sciences, description has
exceeded explanation in dryland areas (e.g. Cooke and Warren,
1973), depriving science of a structured, analytical basis for
understanding the behaviour of the environ- ment. Second, in some
fields, scientific paradigms developed in non-dryland environments
have been imported to inappropriate dryland situations. This is
particularly significant in ecology, where only now is an
appropriate understanding of “disequilibrium” eco- logical systems
being achieved (e.g. Behnke et al., 1992). Distinguishing natural
vegetation system vari- ability, in response to moisture
deficiencies at the seasonal, annual or longer time scales, (e.g.
Tucker et al., 1985) is an important aspect of the correct iden-
tification of desertification. Both these points are sig- nificant
to the understanding of desertification and the manner in which
dryland systems respond to external disturbances (e.g. Dougill et
al., 1999), for in the past misinterpretations of the extent and
nature of deserti- fication have arisen from these sources (Thomas
and Middleton, 1994).
The timetable of desertification: data bases for effective
assessments
The human dimensions of desertification mean that a definition of
the problem must have relevance to human needs. The rate of
occurrence of the negative changes to the environment associated
with desertification is an all-important component of the issue.
Abel and Blaikie (1989) defined rangeland degradation as an
effectively permanent [their italics] decline in the rate at which
the land yields livestock products under a given system of
management’ (Abel and Blaikie, 1989,
113). Ten years on, this definition has been para- phrased to apply
to soil degradation, which has been defined as “an effectively
permanent decline in the rate at which land yields products useful
to local livelihoods within a reasonable time-frame” (Scoones and
Toulmin, 1999, p. 63). These definitions illustrate an important
principle in the determination of desertification, namely that a
temporal dimension, relevant to human needs and activities, should
be incorporated within consideration of the problem. Slow
degradation has little relevance to rural subsistence communities
and their production of food to meet immediate needs. Terms such as
“soil mining” (e.g. Ramisch, 1999) or even “cattle mining” (e.g.
Perkins, 1991), used to describe unsustainable prac- tices, need to
be set in an appropriate societal frame- work, as well as an
environmental one. But in drylands, assessing the rate of change
can be problematic when long term monitoring systems are largely
absent and projections of rates of change and degradation are often
derived from imprecise data sources (e.g. Stocking, 1996). Where
data on regional-scale changes in vege- tation cover are becoming
available, often through the use of remotely sensed media, they can
in some situa- tions be used to show close parallels between desert
“expansions” and retreats and rainfall values (e.g. Tucker et al.,
1991, Nicholson et al., 1998).
Desire to counter the problem faster than knowledge allows
UNCOD highlighted the desertification problem and set an agenda for
its solution. Feasibility studies were presented in 1977 for
tackling different forms of desert- ification (Spooner, 1989). The
Plan of Action to Com- bat Desertification that arose from UNCOD
set a target for eradicating desertification by the year 2000. This
was soon viewed as unfeasible (UNEP, 1981), for a variety of
reasons including financial constraints, not only within affected
countries of the south but also in terms of the limited
contributions that were being made to UNEP’s Special account for
anti desertifica- tion activities (UNEP, 1982; Thomas and
Middleton, 1994). Odingo (1990) has also questioned whether the
scientific and technical know-how to act rapidly in effective
anti-desertification measures actually existed at the time. The
relative level of knowledge about dry- land environmental systems
compared to that for other environments (see above) suggests that
Odingo was correct. Further, issues of whether desertification is
an environmental problem, requiring technical solu- tions, or
societal problem, requiring structural and behavioural changes,
have real impacts on achieving appropriate trajectories for
effectively tackling the problem (see Thomas and Middleton, 1994;
Stiles, 1995).
Into the Third Millennium: The Role of Stakeholder Groups in
Reducing Desertification
5
STAKEHOLDERS
The preceding summary of issues contributing to the controversies
surrounding desertification contains implicitly within it a key
characteristic of all environ- mental issues; namely that there are
different groups of “stakeholders” affected by the issue and who
have different perspectives on the key aspects of the prob- lems
inherent to the issue and relevant to its solution. The
contribution, influence and status of these groups has varied in
the twenty or so years since UNCOD, though all have been involved
to varying degrees throughout. We now turn to consider the
significance of the issues linked to these groups to the manner in
which the desertification problem is perceived, and acted
upon.
The political issue
The high-profile attained by the desertification issue in the late
20th century can be attributed significantly to political
processes. Lobbying by political leaders from Sahel countries
affected by severe drought in the 1970s specifically led to the
establishment of UNCOD (Glantz, 1977), as it was felt (but not
universally agreed upon by all developed state governments) that an
inter- national strategy was necessary to raise awareness of the
problem.
Simplification of the real complexities within an environmental
problem may be essential for global debate and discussion to occur
(Scoones and Toulmin, 1999). This dumbing-down strategy is not new,
as an interesting dryland example illustrates. In the 1940s, when
trying to get the US Senate to agree a financial package to help
farmers in the US midwest “dust bowl”, which had been affected by
soil degradation for several decades, US statesman Dean Acheson is
purported to have advised President Truman to “Scare ‘em Harry, or
nothing will be done”(R.W Simonson pers. com., 1995).
The globalisation of desertification as an issue was undoubtedly a
significant (but not the only) factor in some of the simplistic
representations of the issue. As Barraclough (1995: 23) records:
“The term [desertification] is much more useful for mobilizing
political support to combat what are imag- ined to be desert sands
marching over once-fertile crop lands and productive pastures than
for analysing the causes, effects and proposed remedial actions to
deal with the multiple processes generating land degradation.” A
key purpose of the globalisation of desertification associated with
UNCOD was to generate international financial support for
anti-desertification actions in developing countries, particularly
those with insufficient
resources of their own to do so (Corell, 1999). There is some
evidence to suggest that this effect was achieved. In 1986 for
example, both US and UK gov- ernments were being urged to give
financial aid to Sahel countries on the basis of perceptions of the
Sahara advancing over adjacent areas at a rate of several kilo-
metres per year (Warren and Agnew, 1987, p. 2). The advancing
desert image was also prominent in UNEP publicity in the 1980s (see
Thomas and Middleton, 1994), and Swift (1996) has suggested that
when reli- able data presenting a more complex picture of dryland
land degradation began to appear, it was deliberately
ignored.
Although some authors (e.g. Stiles, 1995) have offered robust
defence of early representations of desert- ification, it is
suggested that this type of “crisis narra- tive” (Scoones and
Toulmin, 1999) is ultimately counter-productive, since even if
widespread interest in, and recognition of, the problem is
engendered, inappropriate and ineffective solutions may be
effected. For whatever reason, in the case of desertification a
different problem in fact befell the actions planned by the UN
Consultancy Group for Desertification Control (DESCON), namely the
lack of financial contributions that were forthcoming from
developed world nations (Thomas and Middleton, 1994).
As well as being a tool for raising international aware- ness of an
environmental problem, it has been pro- posed that the spectre of
desertification has deflected blame from the real causes of social
problems in parts of the Sahel. In an analysis of the causes of
food short- ages in parts of the Sudan in 1983–84, Ollson (1993)
has suggested that financial and political structures that favoured
price rises and discouraged the movement of food stocks available
within the country to areas of real need were more significant than
land degradation in causing drought-related famine.
Science and desertification
There were significant scientific inputs to UNCOD in 1977, in the
form of statements about the nature of desertification and the
preparation of case studies illustrating the occurrence and nature
of the problem (Thomas and Middleton, 1984). Scientific inputs to
the preparation of the CCD, through the International Panel of
Experts on Desertification (IPED) have been assessed by Corell
(1999), and identified as lesser in scale and having a more limited
impact than in the case of UNCOD.
The role of science in the desertification debate has previously
been considered by Thomas (1997). In the period since UNCOD,
systematic scientific research into components of environmental
systems pertinent to desertification has grown considerably, with
notable
D.S.G. THOMAS
Copyright © 2003 Swets & Zeitlinger B.V., Lisse, The
Netherlands
advances occurring in many areas of dryland environ- mental
knowledge (Table 1). Improvements have also occurred within the
understanding of a range of envi- ronmental processes in drylands
including salinization (e.g. Rhoades, 1990), soil nutrient
movements (e.g. Scholes and Scholes, 1989; Tolsma et al., 1987),
range- land ecology (e.g. Walker and Noy-Meir, 1982), vege- tation
responses to stress (e.g. Behnke et al., 1992), and the operation
of aeolian processes, including in relation to vegetation cover
change (e.g. Wiggs et al., 1995). Remote sensing studies have also
contributed to better understandings of both the temporal (season
to season, year to year, and decade to decade) and spa- tial
patterns of flux that operate within components of dryland
environmental systems.
It may therefore seem perverse that scientific con- tributions to
the development of the CCD were limited, since science would appear
to have had more to offer in the 1990s than it did two decades
earlier. Closer con- sideration however suggests that this may be
the very reason for the lesser role; On the one hand, the CCD
needed the authority of a scientific group to legitimise its
negotiations, but on the other hand a more central involvement
would have emphasised the uncertainties surrounding the phenomena
of desertification, thereby reducing the likelihood of an agreed
convention being achieved (Corell, 1999, p. 201).
Despite the advances in the scientific understanding of dryland
systems that has occurred in recent decades, the pace of science
and the nature of scientific research are not necessarily well
attuned to the needs of others involved in the quest to understand
and resolve desert- ification, especially those who seek rapid
solutions to the problem. Bo Kellen, Swedish diplomat and chair of
the negotiations leading to the CCD, is reported to have noted in
1993 that “Scientific controversies are irrelevant to people facing
famine” (Thomas, 1997). An alternative view is that scientific
advances have led to the orthodoxies of desertification been
questioned,
so that far from being irrelevant, science has in fact contributed
to a more realistic view of the complexities of drylands and of the
land degradation that can occur within them.
Societies directly affected by desertification
People affected by desertification, especially those in rural areas
of developing countries, have sometimes been presented as passive
victims of the problem (e.g. in statements such as “the future of
900,000,000 peo- ple at risk” (e.g. UNEP, 1991) or as the root
cause of degradation (see Thomas and Middleton, 1994). Similarly,
poverty has been viewed as a major cause of desertification,
causing people to adopt unsustainable practices for short term
gains, or as an outcome of desertification, resulting from less
productive agricul- ture as lands become desertified. Neither view
is very helpful (see, e.g. Barraclough, 1995), and both have been
challenged, through the outcomes of social science research and
through greater representation of com- munity views in negotiations
leading to the CCD (see below).
Traditional pastoral societies have in particular been viewed, by
outsiders looking in, as irrational in their use of shared natural
resources and in their attitudes to livestock numbers and the
environment. This general- isation has been challenged (e.g.
Livingstone, 1977; Mace, 1991) in social science research that has
in many ways paralleled the revised understanding of the behav-
iour of dryland ecological systems. This has been achieved in the
last ten years or so, since it was noted by Spooner (1989) that
environmental and social sci- entists were largely ignoring each
others efforts and interpretations, yet both were vital for a
sensible under- standing of desertification.
As well as being those directly affected by deserti- fication,
local people are the group of actors through
Into the Third Millennium: The Role of Stakeholder Groups in
Reducing Desertification
7
Table 1 Some scientific advances in1980s onwards, relevant to
desertification issues.
Scientific research has led to an awareness that: 1. Dryland
environments are characterised by significant temporal and spatial
variability in key system components,
e.g. rainfall (see Hulme, 1992) and natural vegetation systems (see
e.g. Warren, 1995 for a summary and discussion). 2. Drought is a
natural dynamic component of dryland rainfall systems (and
subsequently awareness that many
indigenous NR systems are/were adapted to this). 3. The concept of
climax vegetation systems is not appropriate to most dryland
settings, and that many ecological
systems display disequilibrium characteristics (and subsequently
that NR management systems which attempt stable, constant, off take
levels are thus not likely to be successful).
4. The soil resources of many drylands are nutrient poor and in
some cases are closely coupled to vegetation systems (e.g. Dougill
et al., 1999).
5. Natural environmental variability has to be accounted for in
assessments of dryland change and degradation. 6. Feedbacks may
occur between ecosystem changes are lower atmosphere processes,
potentially resulting in the
enhancement of desertification. 7. The lack of spatial and temporal
homogeneity in dryland systems makes the scaling up of data from
small scale
studies inappropriate (Stocking, 1996), and also frequently makes
prescriptive solutions to desertification inappropriate.
Copyright © 2003 Swets & Zeitlinger B.V., Lisse, The
Netherlands
which the environmental and social dimensions of the problem meet,
interact, and generate an outcome (e.g. Thomas and Sporton, 1997).
When traditional soci- eties do conduct actions that lead to
degradation, it is now more common to view this as a function of
their livelihoods and life styles being compromised by structural
and political changes in the 20th century (e.g. Kipuri, 1995) that
lead to a departure from prac- tices that embody good land
husbandary. Noting the history dimension to perceptions of local
people as the cause of degradation, it has been written that facile
generalizations are always plagued by multiple excep-
tions…explanations of desertification assuming peas- ant ignorance
and shortsighteness were especially in vogue with colonial
administrators. These have been largely discredited by research
illuminating tradi- tional peasant farming and social systems and
the processes disrupting them such as land alienation, surplus
extraction and commercialisation. (Barraclough, 1995, p. 33).
Research by Mortimore (1987) in Nigeria identi- fied a ranch of
traditional “insurance strategies” against times of environmental
stress resulting, for example, from drought. Where external changes
result in the adaptation of practices that contribute to land
degradation, these may prove to be transitional and not permanent
(Stocking, 1996). For example, Tiffen et al. (1994) have shown how
slopes in the Machakos District of Kenya that showed signs of
severe soil erosion in the 1930s have in fact be turned into highly
productive cropping systems, due to a change in land tenure
arrangements and the replace- ment of colonially instigated
livestock production systems with indigenous market-driven
cultivation. Whether or not land degradation is actually taking
place may also differ according to the circumstances of the
observer. The erosion of soil from steep slopes, which may appear
to represent significant land degra- dation by some, may in fact be
viewed as beneficial by local land-users if it replenishes soil
fertility in flatter valley bottoms that are more readily accessed
for pro- duction (e.g. Scoones, 1992).
The recognition that people affected by desertifica- tion are not
necessarily the direct cause of the prob- lem, that there are a
wide range of complex socio-environmental interactions that are
mediated by externally-derived structural frameworks, and that
these very people may in fact hold the vital keys to successful
degradation mitigation, are views that have now permeated
considerations of the most successful ways to combat
desertification and land degradation.
It is however important that one set of generalisa- tions about
desertification, including those that include generalised views
about local peoples, are not replaced by another. In many parts of
Africa, land tenure systems are dynamic, and continually
evolving
(Thebaud, 1995). The relationships between different groups within
rural populations may be complex (e.g. Hagmann and Murwira, 1996;
Sithole, 1995), while population movements and displacements due to
fac- tors including conflicts (Hendrickson et al., 1998), land
tenure and ownership changes brought about by national policies
(e.g. Sporton et al., 1999) and the quest for greater incomes in
urban areas (e.g. Millington et al., 1989) are amongst the factors
that may in practice make direct routes to locally-based
anti-desertification activities less than simple to
implement.
Non-Government Organisations
Non-Government Organisations participated widely in the processes
contributing to the CCD, such that it is necessary to consider them
as a further important stakeholder-group in desertification. The
term NGO is in itself a catch-all that embraces a wide range of
groups, some scientific, some political, some lobby groups and some
more concerned with aid-related activities, including the dispersal
of funds sourced in central governments. Conflicts may even exist
between the aims and purposes of specific NGOs involved in the same
environmental issue. The role of NGOs within the desertification
convention process included lobbying for particular interests,
providing information and knowledge and, of particular impor-
tance, acting as agents of social change (Corell, 1999). About 50%
of NGOs involved in the CCD negotia- tions came from Africa, and
these contributed in par- ticular to reinforcing the need for the
incorporation of local and indigenous knowledge and for “bottom-up”
action in future plans to combat desertification.
How an international initiative such as the CCD can effect
successful bottom-up actions may in fact lie in the hands of the
NGOs, especially those working at grassroots level that may be in a
position to integrate local-population based factors and actions
into the components of the international agreement that have a
local bearing. NGOs themselves are aware of the potential
difficulties in effecting a useful role in implementing the CCD,
and these have been reflected within their own international
desertification network – RIOD (Reseau International d’ONG sur la
Desertification). It has for example been noted that to date the
most effective NGO interventions in environ- mental problems have
been in terms of addressing short term problems (for example,
drought impacts), including working within existing national policy
frameworks. Action in the context of the CCD will require sustained
actions and also may generate needs to challenge existing policy
frameworks in some affected countries. In India for example, it has
been
D.S.G. THOMAS
Copyright © 2003 Swets & Zeitlinger B.V., Lisse, The
Netherlands
noted that many NGOs only have local spheres of influ- ence which
may render them relatively ineffective in sit- uations where
national changes of policy may be required (Kohler-Rollefson,
1995). In other situations competition between NGOs has led to a
lack of con- certed effort against national policies that may
enhance environmental degradation.
Discussion: global, national or local ?
In practical terms, bridging the global-to-local gulf is critical
in debates about the effective assessment of, and establishment of
solutions to, desertification. On the one hand, to receive
prominence amongst the plethora of big environmental themes, action
against desertification needs global co-ordination, at the very
least to give the matter a global presence. The global dimension is
also relevant since money to finance self help and remedial
actions, especially in the develop- ing world is needed, and the
CCD cannot afford to suffer the same financial setbacks and
shortfalls of ear- lier internationally co-ordinated efforts. On
the other hand, several of the major controversies surrounding
desertification can be traced to its global dimension, notably
questions of whether desertification is actually a myth (Binns,
1990; Swift, 1996), and whether the extent of the problem has been
exaggerated (e.g. Thomas and Middleton, 1994). In a report on
African soul fertility management, prepared for the UK Depart- ment
for International Development, Scoones and Toulmin (1999) have
recently summarised the scale issue and its importance: “Global
initiatives such as the CCD, and the [World Bank-co-ordinated] Soil
Fertility Initiative provide a means for getting attention paid to
formerly neglected areas and themes. However the very simplicity of
the
message they present … provides a misleading and potentially
damaging assessment of what is happening.”
There does indeed appear to have been a crisis of confidence in
intervention in desertification at the institutional level (Warren,
1995). This may have been influenced by a range of factors, many
derived from sci- entific developments and the appreciation of the
rightful role of local actions in tackling land degradation (Table
2). Now small is beautiful, variability and vari- ety are seen as
more relevant than generalisations, and bottom-up actions as more
likely to be successful than those applied at higher levels. But
the two levels should not necessarily be instantly divorced, for if
community action and indigenous knowledge are given greater weight
and opportunity as a result of the CCD, it should not be
automatically assumed that the impacts of desert- ification would
be mediated against successfully.
Community actions, and the ability to apply local knowledge, will
still have to operate within whatever national and international
frameworks influence the potential opportunities (e.g. Sithole,
1995). Because it is now fully accepted that: “Dryland degradation
(desertification) does not involve moving sand dunes, Rather, it
concerns the gradual impoverishment of agricultural and pastoral
systems, which makes them less productive and more vulnera- ble to
drought (Toulmin, 1995, p. 5); then it is also implicitly agreed
that the problem is a complex one, with solutions that are equally
complex, specific and in need of involving the participation of
those who bear local knowledge and are most likely to benefit from
suc- cessful outcomes. The recognition of this was largely achieved
through the realisation, including amongst politicians, that a
generalist approach was not work- ing; through advances made in
environmental and social science research that contributed to a
clearer understanding of the complexities of drylands, and
Into the Third Millennium: The Role of Stakeholder Groups in
Reducing Desertification
9
Table 2 Factors contributing to changing perceptions of
desertification, its causes and solutions.
a) Lack of materialisation of funds in UNEP’s Special Account, thus
prohibiting significant UN-derived top-down action; b) Top-down
projects, funded by e.g. the World Bank and donor North
governments, proving expensive and lacking the
support and interest of directly affected local peoples (e.g. see
Zaal et al., 1998); c) Improved research-derived understanding of
the nature and dynamics of dryland environments including awareness
of
significant temporal and spatial variability (e.g. Hulme, 1992;
Thomas 1993; Warren 1995) and the inapplicability of environmental
paradigms directly transferred from temperate environments (e.g.
Behnke et al., 1992);
d) Equivalent challenges to accepted (western derived) orthodoxies
about people-environment relationships (especially in Africa: e.g.
Leach and Mearns, 1996), including the use of open access systems
that had previously been seen as disorganised by western eyes
(Woodhouse, 1997);
e) Awareness of the richness of local peoples’ knowledge and
experience of their environments, and their resourcefulness in the
face of difficulties (e.g. Adams, 1996; Scoones et al., 1996; Deme,
1998);
f) Awareness of the complex milieu of social, political and
economic circumstances affecting local peoples behaviour and
relationships with the environment and natural resources, including
interactions between livelihoods, poverty/wealth levels and
structural changes associated with post-colonial changes in African
countries (see e.g. Barraclough, 1995);
g) Awareness of the holistic nature of many environmental problems:
the realisation of links between different environmental issues
world-wide and social-environmental issues in Africa (e.g. Cardy,
1997; Squires and Glen, 1997), resulting in benefits being ascribed
to multi-pronged and multi-directional approaches, analyses and
solutions.
Copyright © 2003 Swets & Zeitlinger B.V., Lisse, The
Netherlands
through a greater voice being given, at least in part due to the
role of NGOs, to the views, concerns and knowledge of local people
in affected areas.”
National Action Programmes are a cornerstone of the CCD, but unlike
the National Plans of Action prepared after UNCOD, which tended to
be top-down and rather general in approach (Thomas and Middleton
1994), the NAPs being produced under the CCD have a greater
emphasis of participatory activities involving local communities
and practical actions that can be taken to redress and inhibit land
degradation. Recognising how- ever that desertification is not
solely confined within national boundaries, Regional and
Sub-regional Action Programmes are also encouraged within the CCD,
not as an up-scaling exercise but as one that that allows for the
integration of good practices and the mutuality of approaches
appropriate within geographic regions.
Just as local action is necessary within actual anti-
desertification actions, so science retains an important role too.
This includes retaining issue clarity, deserti- fication
monitoring, identifying appropriate scales of action in specific
spheres of degradation and identify- ing characteristics of
environmental system recovery and the relationships between this
and human actions (Thomas, 1997), as well maintaining a watching
brief on the interactions between desertification and other major
environmental issues such as global warming and biodiversity loss
(Cardy, 1997). The CCD includes the need for the establishment of
the Committee of Science and Technology, to play a number of roles
relating to anti-desertification measures. The CST is not however a
global-level “elite” but has a role to co-ordinate, assimilate and
disseminate the beneficial information gained from local knowledge
and expert- ise, in a manner that links science with local action
(e.g. van Rooyen, 1998). The overall CCD includes within it
obligations for the countries that are party to it, includ- ing the
need to work towards eliminating poverty and recognising the roles
of local peoples and NGOs in efforts to eliminate desertification.
While, in the 20- odd years since UNCOD, the balance of importance
attached to the different groups of players in the desertification
issue, politicians, scientists and local people are all critical
parties if desertification is to be successfully managed and
reduced.
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D.S.G. THOMAS
INTRODUCTION
Even though arid lands cover a third of the earth’s land surface
and are already subject to severe land degra- dation
(desertification) pressures, remarkably little thought has been
given to what might happen to arid lands as a result of any
potential warming associated with the enhanced greenhouse effect.
Indeed, those sections of the reports of the Intergovernmental
Panel on Climate Change that deal with deserts are notable for
being narrow and for neglecting almost all the most important
issues (Bullock and Le Houérou, 1996; Noble and Gitay, 1996). Some
of the regional studies are no more satisfactory, and the one on
Africa contains one paragraph only on deserts and concludes with
the fol- lowing debatable remark (Zinyowera et al., 1998, p.
43):
“Extreme desert systems already experience wide fluctuations in
rainfall and are adapted to coping with sequences of extreme
conditions. Initial changes asso- ciated with climate change are
less likely to create conditions significantly outside present
ranges of tol- erance; desert biota show very specialized
adaptations to aridity and heat, such as obtaining their moisture
from fog or dew.”
The reality is that arid environments often appear to have been
prone to rapid geomorphological and hydro- logical changes in
response to apparently modest cli- matic stimuli, switching
speedily from one state to another when a particular threshold is
reached (Goudie, 1994). River systems are prone to episodes of cut
and fill; alluvial fans accrete and trench; colluvial aprons show
complex sequences of deposition, stability and incision; drainage
density and rates of erosion can change very rapidly either side of
a critical level of vegetation cover; terminal lake basins expand
and contract and freshen and salinate; dust storm activity shows
marked shifts in response to runs of dry years and/or increasing
land use pressures; and sand seas
appear to have been prone to repeated fluctuations in deposition
and stabilisation. This apparent instability and
threshold-dependence of a range of desert phenom- ena leads us to
believe that such areas may be especially susceptible to the
effects of potential global warming caused by the enhanced
greenhouse effect (Figure 1).
Wind erosion of soils
Changes in climate could affect wind erosion either through their
impact on erosivity or through their effect on erodibility.
Erosivity is controlled by a range of wind variables including
velocity, frequency, duration, magnitude, shear and turbulence.
Such wind characteristics vary over a whole range of time-scales
from seconds to mil- lennia. For example, Bullard et al. (1996)
have shown how dune activity varies in the SW Kalahari in response
to decadal scale variability in wind velocity, while over a longer
time-scale there is evidence that trade-wind velocities may have
been elevated during the Pleistocene glacials (Rea, 1994).
Unfortunately, Gen- eral Circulation Models as yet give little
indication of how wind characteristics might be modified in a
warmer world, so that prediction of future changes in wind
erosivity is problematic.
Erodibility is largely controlled by vegetation cover and surface
type, and both of these can be influenced markedly by climatic
conditions. In general, vegeta- tion cover, which serves to protect
the ground surface and to modify the wind regime, decreases as
conditions become more arid. Likewise climate affects the nature of
surface materials by controlling their moisture con- tent, the
nature and amount of clay mineral content (cohesiveness) and
organic levels. Soils that are dry have low clay content and little
binding humus are highly susceptible to wind erosion.
The Impacts of Global Warming on the Geomorphology of Arid
Lands
A.S. GOUDIE School of Geography and the Environment, University of
Oxford, Oxford, UK
ABSTRACT: Deserts may change significantly in response to global
warming. Modest climatic stimuli may cause vegetation, hydrology
and geomorphology to switch speedily from one state to another.
Changes in vege- tation cover, associated with a decline in soil
moisture availability, will increase the risk of soil erosion by
wind, may accelerate dust storm activity and cause sand dunes to be
reactivated. Large changes in runoff will also occur, leading to
marked changes in the nature of river channels. Closed depressions
are also sensitive to climate change, and so lake levels may be
greatly altered. Finally, arid coastlines will be subjected to sea
level change that will lead to transformations in the nature of
such environments as deltas, estuaries and sabkhas.
Desertification in the Third Millennium. Edited by A.S. Alsharhan,
W.W. Wood, A.S. Goudie, A. Fowler and E.M. Abdellatif. © 2003 Swets
& Zeitlinger Publishers, Lisse, The Netherlands, ISBN 90 5809
571 1, p.13–20.
Copyright © 2003 Swets & Zeitlinger B.V., Lisse, The
Netherlands
However, modelling the response of wind erosion to climatic
variables on agricultural land is vastly complex, not least because
of the variability of soil characteris- tics, topographic
variation, the state of plant growth and residue decomposition, and
the existence of wind breaks. To this needs to be added the
temporal variabil- ity of aeolian processes and moisture conditions
and the effects of different land management practices (Leys,
1999), which may themselves change with climate change.
Dust storm activity
The changes in temperature and precipitation conditions that
occurred in the twentieth century (combined with land cover
changes) had an influence on the develop- ment of dust storms
(Goudie and Middleton, 1992). These are events in which visibility
is reduced to less than one kilometre as a result of particulate
matter, such as valuable topsoil, being entrained by wind. This is
a process that is most likely to happen when there are high winds
and large soil-moisture deficits. Prob- ably the greatest incidence
of dust storms occurs when climatic conditions and human pressures
combine to make surfaces susceptible to wind attack.
Possibly the most famous case of soil erosion by deflation was the
Dust Bowl of the 1930s in the USA. In part this was caused by a
series of hot, dry years which depleted the vegetation cover and
made the soils dry enough to be susceptible to wind erosion, but
the effects of this drought were gravely exacerbated by years of
over-grazing and unsatisfactory farming techniques.
Attempts to relate past dust storm frequencies to simple climatic
parameters or antecedent moisture conditions have frequently
demonstrated rather weak relationships (Bach et al., 1996),
confirming the view that complex combinations of processes control
dust emissions. Nevertheless, evidence is now emerging that relates
dust emissions from Africa to changes in the North Atlantic
oscillation (Moulin et al., 1997).
If, however, soil moisture levels decline as a result of changes in
precipitation and/or temperature, there is the possibility that
dust storm activity could increase in a warmer world. A comparison
between the Dust Bowl years of the 1930s and model prediction of
pre- cipitation and temperature for the Great Plains of Kansas and
Nebraska indicates that conditions could be similar to those of the
1930s under enhanced green- house conditions (Smith and Tirpak,
1990), or even worse (Rosenzweig and Hillel, 1993).
If dust storm activity were to increase as a response to global
warming it is possible that this could have a feedback effect on
precipitation that would lead to further decreases in soil moisture
(Tegen et al., 1996; Miller and Tegan, 1998). However, the impact
and occurrence of dust storms will depend a great deal on land
management practices, and recent decreases in dust storm activity
in North Dakota have resulted from conservation measures (Todhunter
and Cihacek, 1999).
Sand dunes
Sand dunes, because of the crucial relationships between vegetation
cover and sand movement, are highly susceptible to the effects of
changes of climate.
A.S. GOUDIE
Plant physiological
response Temperature
beach retreat
Sediment movement
Figure 1 Some hydrological and geomorphological consequences of the
enhanced greenhouse effect in drylands.
Copyright © 2003 Swets & Zeitlinger B.V., Lisse, The
Netherlands
Some areas, such as the south west Kalahari (Stokes et al., 1997)
or portions of the High Plains of the USA (Gaylord, 1990) may have
been especially prone to the effects of changes in precipitation
and/or wind veloc- ity because of their location in climatic zones
that are close to a climatic threshold between dune stability and
activity.
One of the more remarkable discoveries of recent years, brought
about by the explosive development in the use of thermoluminescent
and optical dating of sand grains and studies of explorers’
accounts (Muhs and Holliday, 1995), is the realisation that such
marginal dune fields have undergone repeated phases of change at
decadal and century time-scales in response to extended drought
events during the course of the Holocene. Dates for reaction phases
are given for the Nebraskan Sandhills by Stokes and Swinehart
(1997) and Muhs et al. (1997), for Kansas by Arbogast (1996), and
for the South West Kalahari by Thomas et al. (1997).
The mobility of desert dunes (M) is directly propor- tional to the
sand-moving power of the wind, but indi- rectly proportional to
their vegetation cover (Lancaster, 1995, p. 238). An index of the
wind’s sand-moving power is given by the percentage of the time (W)
the wind blows above the threshold velocity (4.5 m S1) for sand
transport. Vegetation cover is a function of the ratio between
annual rainfall (P) and potential evapotranspiration (PE).
Thus,
M W/(P/PE)
Empirical observations in the USA and southern Africa indicate that
dunes are completely stabili