The adoption of water conservation application techniques

A number of farm application irrigation technologies that could contribute to the conservation of water in both surface and piped systems have been developed. These techniques are generally adopted for the cultivation of high value crops. About 20 million hectares worldwide are now irrigated by sprinkler irrigation. Micro-irrigation as a technology has matured into reliable water and fertigation management system for crop production over the past decades and its usage continues to increase rapidly. A total of 3.2 million hectares are being irrigated by micro-irrigation techniques throughout the world, which represent one percent of the total areas irrigated in the world. A growth of more than six times over the last 20 years has been achieved, which is quite a success. Micro-irrigation is an important tool in the drive towards food security. Micro-irrigation systems have great potential to create significant opportunities for smallholder agriculture.

During the 1980s micro-irrigation started penetrating developing countries, mainly India. A few years later, fearing a water and food shortage, the Chinese Government declared drip irrigation technology to be amongst the top priorities for development in the last decade. However, Vidal et al., (2001) have shown that micro-irrigation “is not a miracle technology: excellent as well as poor results were obtained from these technologies, and their adoption really depends on farmers capacity to finance and operate them, as well as on the type of crop production”.

According to the ICID database on modern irrigation techniques, it appears that the use of pressurized water application techniques is widely different between countries. The percentage of modern technique decreases with the total area irrigated in developed countries from a low of 21 percent in the USA and 16 percent in Italy to 90 percent or over in Northern European countries (France and Germany). Sprinkler has a much greater application compared to that of the drip systems with the exception of Cyprus, Israel and Jordan.

In South Asia and Africa low cost bucket-and-drip sets are becoming increasingly popular with farmers. In areas where shallow groundwater is plentiful, thousands of poor farmers in Bangladesh have used low-cost treadle pumps to supply water for crops for their own food security and additional income.

Advanced surface irrigation techniques such as precise land levelling, gated pipes or cablegation have also been developed to improve the typical poorly distributed application of water under conventional methods by furrow, border or basin irrigation. Experience shows that these techniques are too sophisticated to be adopted by most smallholders in developing countries. Adaptive research in the Middle East and North Africa has shown the difficulties in introducing surface water conservation techniques. Many attempts to introduce gated pipes in Morocco for example have failed for a number of reasons, mainly the poor maintenance of the quaternary earth canals. Considerable efforts for training of farmers in water conservation in surface systems are needed.

Farmers have adopted pressurised systems much faster than surface application techniques. For example, about 65 percent of the farmers in the Jordan valley have shifted from surface to drip irrigation over a 10-year period. Farmers built on-farm storage reservoirs to provide the flexibility required for drip irrigation.

Although there are no statistical data available on it, it is likely that most of the areas irrigated through water conservation techniques are served from wells or piped systems. There is still a huge potential for development of water conservation techniques in the areas presently irrigated from groundwater. Application of these techniques will continue to expand with the market for high value crops. However, the adoption of these techniques is limited to the cultivation of certain crops because of technical and financial considerations.