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Regional Workshop on Management of Salt-Affected Soils in the Arab Gulf States

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Regional Workshop on Management of Salt-Affected Soils in the Arab Gulf States Proceedings of the REGIONAL WORKSHOP ON MANAGEMENT OF SALT-AFFECTED SOILS IN THE ARAB GULF STATES Abu-Dhabi, United Arab Emirates 29 October - 2 November 1995 RE ORGANIZATION OF THE UNITED NATIONS OFFICE FOR THE NEAR EAST . Cairo, 1997 Proceedings of the REGIONAL WORKSHOP ON MANAGEMENT OF SALT-AFFECTED SOILS INTHE ARAB GULF STATES Abu-Dhabi, United Arab Emirates 29 October - 2 November 1995 FOOD AND AGRICULTURE ORGANIZATION OF THE UNITED NATIONS· REGIONAL OFFICE FOR THE NEAR EAST Cairo, 1997 TABLE OF CONTENTS FORWORD .................................................................... .. ................ III Summary ofReco=ended Priority Areas for Follow Up ............................ IV I. SALINITY IN THE NEAR EAST: A REGIONAL PERSPECTIVE 1. An Overview of the Salinity Status of the Near East Region, by Ghassan Hamdallah ..................................................................... 2 2. Improvement ofItrigation and Drainage Systems for Soil Salinity Control in the Arab Region, by Mustafa AI-Hiba .... ............................ 7 II. MONITORING AND RECLAMATION OF SALT-AFFECTED SOILS 3. Drainage and Salinity Investigation Techniques for the Diagnosis of Land Degradation, by Rami Zurayk .................................................... 12 4. Pilot Areas for the Reclamation of Salt-Affected and Waterlogged Soils, by Fernando Chanduvi ............................................................. 20 5. A National Plan for the Reclamation ofIrrigated Areas Degraded by The designations employed and the presentation of the material and maps in this Salinity and Waterlogging, by Fernando Chanduvi ............................. 24 document do not imply the expression of any opini?n whatsoev~r on the part of the 6. Soil Salinity Assessment: Recent Advances and Findings, Food and Agriculture Organization of the United Nallons concernmg the legal.'~tu~ of by J.D. Rhoades ................................................. ....... ............. ..... .... ... 28 any country, territory, city or area or of its authorities, or concerning the delirnitallon 7. Hydraulic, Chemical, Physical and Biological Techniques for the of its frontiers or boundaries. Reclamation o{Salt-Affected Soils, by Amin Mashali ......................... 34 8. Reclamation and Management of Salt-Affected Soils, by Fareed Abdul Nabi ........................................................................ 52 9. Measuring and Monitoring Soil Salinity, by J.D. Rhoades ................... 55 ID. TECHNICAL CONSIDERATIONS IN IRRIGATING WITH SALINE WATER 10. Water Management for Salinity Control, by Fernando Chanduvi ........ 64 11. Suitability Assessment of Water Quality for Irrigation, by J.D. Rhoades. ........................... .... ..... ........ ............. ......... ..... ......... 67 12. Strategies for the Use of Multiple Water Supplies for Itrigation and ~ Crop Production, by J.D. Rhoades... ... .................... .... .......... ..... ......... 80 13. Itrigation Systems, Water Quality and Management in Salt-Affected Soils: Case Study from the UAE, by Mohammad Sakr AI-Asam .......... 89 IV. CROP RESPONSE TO SALINITY 14. Use of Saline and Brackish Waters and the Relationship with Soil Management, by Gilani Abdelgawad, Abdel Nabi Fardous and Z. AI-Shabouni ....................................................................................... 94 15. Availability of Nutrients, Fertilizer Management and Crop Tolerance Under Saline Conditions, by Amin Mashali ..... ...... .............................. 100 16 . Soil-Plant-Water Relationships in Salt-Affected Soils, by Rami Zurayk................................................................................. 114 V. COUNTRY PAPERS 1. Crop Management in Irrigated Land Particularly in Salt-Affected Soils of the UAB, by Mohammad Hashim ........................... 123 ii. Salinity Problem in the Soils and Water of Bahrain, by Ali Ahmed Nasir ...... .... ...... .............. ........... .... ....... ..... ... 127 Ill. Salt-Affected Soils in Qatar, by Ghanem AI-Ghanem .......................... 128 IV. Soil Resources in the UAB, by AhmedAI-Barshamgi..................... 129 v. The Use of Salt-Affected Soils and Saline Water in Agriculture in the United Arab Emirates, by Rashid Al Mehrizi ..... ..... .... ....... ... ......... 13 0 vi. Salt-Affected Soils in Saudi Arabia, by Ahmed S. AI-Shareef .............. 132 vii. Salt-Affected Soils in Kuwait, by Samir AI-Ghawas........ ..... ............... 133 VU1. Salt-Affected Soils in Oman, by Ishac AI-Gabri.................................. 134 VI. ANNEXES Annex l. List of Participants ..................................................................... 136 Annex 2. Workshop Programme ............................................................... 140 II FOREWORD Salinity is a global problem highly affecting 20 to 30 million ha., rendering them unfit for food production. According to FAO, as much as double that area is classified as "less affected" by salinity but remains vulnerable and susceptible to improper irrigation practices, deforestation, overgrazing and other abuses. In arid and semi-arid areas, such as in the Near East Region, irrigation plays an important role in the overall agriculture sector by producing over 1/3 of the agricultural output. In some countries where rainfall is scanty, irrigated areas are the backbone of their agricultural activity and the main contributors to food security. In its Continuous efforts to combat hunger, F AO recently launched the "Food For All Campaign. Irrigation was given prime attention in the Campaign's Special Programme for Food Security (SPFS). Soil conservation/rehabilitation, water harvesting and small scale irrigation schemes also figured in prominently in SPFS. The present volume documents for the "Regional Workshop on Management of Salt-Affected Soils in the Arab Gulf States". The F AO Regional Office sponsored the workshop in response to a request made by the Gulf States themselves. It is our hope that the review of the latest on monitoring and evaluating the effects of salinity would contribute positively to national activities. Especially in adopting feasible practices to combating soil and water salinization. ari ADGlRegional Representative for the/Near East III Regional Workshop on Management of Salt-Affected Soils in the Arab Gulf States SUMMARY OF RECOMMENDED PRIORITY AREAS At the Closing Session of the above Regional Workshop, held in Abu Dhabi, the United Arab Emirates (29 October to 2 November 1995), the participants concluded that the issues listed below were deemed priorities and governments, organizations and research institutions in the Region were urged to give them due consideration: 1. Collect and update data and studies concerning salinization of soil and water resources, in order to assess the salinity problem and its impacts on agricultural and environmental aspects. 2. Each state of the Region was encouraged to monitor the irrigation-induced salinity and to evaluate the effect of using different water quality on the soil salinization process, for eventually making the choice of proper irrigation practices and quantities of irrigation water required. 3. The FAO Regional Office for the Near East was requested to prepare studies, hold seminars, expert meetings and training courses, as well as disseminating relevant documents for the purpose of information exchange and training of national cadre in their endeavour to combat soil salinization resulting from the expansion in irrigated agriculture. 4. Urge Governments of the Region to promote the use of non-conventional water resources, such as treated wastewater, with the proper choice of modern irrigation systems; and request FAO and the Regional Office to provide the necessary information and relevant research studies on the subject in order to utilize such "special type" of water with full consideration to public health and the environment. 5. The need to hol~ "specialized courses" for training national cadre on the practical aspects of adopting new technologies available related to modern irrigation systems, as well as new methods for salinity monitoring and assessment. 6. The real necessity to integrate the salinity studies and related research results within the/agricultural extension programmes in order to ensure the exposure of farmers to such information. 7. Urge governments of the Region to draw plans for conducting integrated studies for salinity monitoring and assessment, including all related aspects of soil, water, crops and the environment in order to achieve meaningful and applied results. IV 1. Salinity in the Near East: a Regional Perspective. An Overview of the Salinity Status ofthe Near East Region Ghassan Hamdallah Regional Soils Officer FAD Regional Office for the Near East INTRODUCTION The Near East is a semi-arid to arid region, where irrigation is necessary for agriculture: irrigated lands cover 34% of the arable land area and account for 75% of crop production. With one of the highest rate of population growth, the region is highly dependant on imported food, mainly from Europe and the US. A quick look at the region's natural resources reveal that the situation is very critical due to the limited arable land and water resources. Therefore, agricultural development plans and policies for land management are required in order to ensure sustainable productivity, better use of land and water resources and to reduce environmental degradation. Soil salinity is an ancient problem in the Near East. The people of Mesopotamia shifted
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