Improving water use efficiency in drylands

Drylands cover 41% of the global terrestrial area and 2 billion people use it for grazing and cropping. Food security is low owing to institutional and technical constraints. Absolute water scarcity and also the inability of crops to use available water are major technical issues. Significant progress has been made in identifying land management practices that improve water use efficiency in terms of more crop per drop. Examples are presented that improve infiltration and storage of rainwater, reduce evaporation losses, harvest and conserve water in the Mediterranean region and Africa and use treated waste water for irrigation. Drylands show a wide diversity and therefore, require appropriately adapted best mitigation practices and strategies.

► Drylands suffer from water scarcity and the inability to use available water. ► Soil surfactants increase infiltration and mulch reduces soil evaporation. ► Innovative methods conserve rainwater in situ or harvest it for use elsewhere. ► Our large volume of waste water can be re-used provided adequate treatment. ► Technology to improve water use efficiency exists but adoption is low.