Managing Scarce Water Resources in Agriculture in West Asia and North Africa - Restorative Redevelopment of Devastated Ecocultural Landscapes - page 437

22 ManagingScarce

WaterResourcesin
AgricultureinWest
AsiaandNorthAfrica

Theib Y. Oweis and Ahmed Y. Hachum

CONTENTS
Extent of Water Scarcity in Dry Areas .................................................................. 452
Declining Agricultural Share of Water................................................................... 455
Options for Coping with Water Scarcity ................................................................ 456
Developing New Water Supplies....................................................................... 456
Utilizing Marginal-Quality Water .................................................................... 457
Regional Water Transfer.................................................................................... 458
Rainwater Harvesting ....................................................................................... 459
Import Virtual Water.......................................................................................... 459
Demand Management, Water Pricing ...............................................................460
Increasing Agricultural Water Productivity............................................................460
Evolution of the Water Productivity Concept ................................................... 461
From Efficiency to Productivity ........................................................................ 461
The Water Accounting Framework ................................................................... 463
Water Productivity Performance Indicators ......................................................464
Economic Water Productivity............................................................................464
Responses to Improve Water Productivity ............................................................ 465
Deficit Irrigation................................................................................................ 465
Changing Current Land Use .............................................................................466
Precision Irrigation............................................................................................466
Case Studies from the Middle East ........................................................................ 468
Supplemental Irrigation Improves Rainfed Agriculture.................................... 468
Improved Water Productivity in Irrigated Agriculture ..................................... 476
Water Harvesting for the Drier Environments—Steppe.................................... 478
WP Improvement and the Environment ............................................................ 481
Policies and Institutions .................................................................................... 482
Conclusions............................................................................................................ 482
References.............................................................................................................. 483

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