Raised-bed planting: maximizing water use efficiency
An improved surface irrigation technique is offering farmers a practical and more sustainable alternative to conventional irrigation systems which tend to be highly inefficient and waste already-scarce water resources. Raised-bed planting – where crops are planted on ridges and irrigation water is applied to the bottom of furrows – is a priority of the ‘Enhancing Food Security in Arab Countries’ initiative, an ICARDA-managed program aiming to improve wheat production across nine Arab countries.
Instead of spreading water over the entire surface area – the practice most commonly applied by farmers – raised-bed planting collects water more efficiently, applying this precious resource where it is most needed. Its introduction in Egypt and Sudan is not only improving water use efficiency – the amount of crop generated per m3 of water – but raising yields and boosting farmer incomes.
Raising yields while improving water-use efficiency
Impacts in Egypt’s Al-Sharkia Governorate, where the innovation was disseminated, have been particularly impressive. The results, obtained during the initiative’s first phase, compared the raised-bed technique with conventional flat surface irrigation. They include:
- A 25 percent average saving in applied irrigation water
- A 30 percent average increase in grain yield
- An average 73 percent increase in water use efficiency
- A 30-50 percent saving in the quantity of seed used for planting.
In addition, raised-bed planting brought savings in energy and labor. The average time needed to pump water to irrigate one hectare (ha) of wheat planted on a raised bed was 29.4 hours, compared to 43.9 hours on a flat field. The subsequent reduction in the costs of labor and fuel – approximately 33 percent – contributed to a rise in farmer incomes.
In Sudan, raised-bed planting was also tested, and demonstrated that wheat yields could be increased by an average of 15 percent. In Morocco, water-use efficiency increased by 13 percent compared to basin irrigation.
In all three countries the practice is gaining wider support. In Al-Sharkia, for instance, land devoted to raised-bed sown wheat increased from 950 ha in 2009/10 to 33,600 ha in 2014/15. A similar trend has been noted nationwide across different parts of Egypt. Raised-bed planting now covers some 105,000 ha – the result of government efforts to replicate successes in Al-Sharkia.