Juan G. R. Irrigation strategy against drought.
Newspaper Information. Alicante , Spain , Pág.18, 9/3/2006 .
The insufficient rainfall in Spain in the year 2006, which caused difficulties in ensuring a optimal irrigation regime of crops in the major irrigation areas of the country, more so if one takes into consideration that we are in the middle of the second year consecutive drought and the water shortage in the current year is about 25% compared with the normal year. Under these conditions the surface water reserves in the reservoirs of the basins South Segura and Jucar are below 30%, basins of river Tajo and Guadalquivir are below the 50%, reserves in the basins of the Duero and Guadiana below 60%.
Faced with such a situation, the prognosis is that the drought is severe, there will be major economic losses in agriculture by water shortage, we must prepare for the fight against drought and make a proper strategy for irrigation, especially in those basins that water reserves are below 50%, with a priority on those basins where water reserves of the reservoirs are below 30%, which relate to large irrigated areas of the Mediterranean.
The Agriculture is the biggest user of water resources in the country, implying that it is necessary to clarify the water demands of individual users and volumes of water delivery guaranteed sources of supply underground and surface, which possible supply of a strategic resource increasingly necessary and deficient.
Proper management of irrigation water by the suspension of some irrigation in certain phases of development of the crop and implementation of reduced irrigation water volume, allow savings of 10 to 20% of the volume required by the crop, without a significant reduction in the agricultural yields. An irrigation excess or deficit irrigation in protracted decline farm yields, hence the importance of making a rational use of irrigation water.
When the water deficit occurs during a certain stage of a crop, the same effect on performance can vary widely, depending on the sensitivity of the crop in that period. Overall the crops are more susceptible to water deficit during germination, flowering and initial formation of the crop than during the growing period after the establishment and in the final stage of development of the crop. A prolonged water shortage in the critical stages of the crop, has a direct impact on yields and hence the economic effectiveness of crops. The more critical phase of demand varies with the water requirements of each crop, which makes it necessary to establish annually prognosis management of irrigation water used in each crop according to the climatic hydrological year in question, for determinate agricultural regions of the country, in irrigation conditions.
The irrigation water management has great practical and economic interest as possible to establish that volumes of water should be applied at different stages of cultivation, and in what moment the water needs become more critical. Research in various countries and conducted himself with a group of researchers have shown that an optimal irrigation regime and a rational irrigation water management increase yields and the quality of the harvest and have a strategic character in the use of water.
The irrigation areas of the Valencia are about 350000 hectares , with a net total water demand of 1925 hm3 / year, to reach users a proper management of water irrigation can be achieved savings of around 15% the total demand for irrigation, which represents a volume of 289 hm3/año, of whom 86 hm3/año correspond to the province of Alicante. A water-saving in the volume of delivery per unit area of irrigation, is also in energy savings and a reduction in costs of irrigation, implying that the proper management of irrigation is a measure of great economic technical effect.
The management of irrigation water, efficient irrigation systems and wastewater reuse all have to be applied together in a developed agriculture, since they enable a more rational use of water. we must prepare for the fight against drought and make a proper strategy for irrigation, we must prepare for the fight against drought and make a proper strategy for irrigation and reach a rational use of the water