An integrated irrigation study. An example with Lucerne (Medicago sativa) growing under semi-arid conditions in Cyprus
1982
Orfanos, P. | Metochis, Ch. (Agricultural Research Inst., Nicosia (Cyprus))
The procedures and the results of a series of experiments made over the period 1970-80 at Athalassa near Nicosia, in Cyprus are briefly described (extended reports on these experiments have been published elsewhere). The experimental site has a semi-arid climate typical of the inland areas of east Mediterranean regions (mean maximum temperature for July-August 35.5 deg C, extreme maximum temperatures 40-42 deg C, average annual rainfall 300 mm). Under these conditions lucerne has to be regularly irrigated from March till November. The experiments aimed to determine the water requirement of the crop, to relate the water requirement to evaporation rates or evaporation estimates obtained by various formulae, to determine how often the crop should be irrigated and to explore whether irrigation could be restricted without unduly reducing yield. The water requirement was determined using a field water balance method in which drainage losses were calculated from predetermined hydraulic conductivity values and frequently measured tension and water content values. Evapotranspiration ranged from 1.0 mm/day in December-January to 8-10 mm/day in June-July-August, and correlated best with evaporation values from a USWB Class A pan evaporation estimates obtained with a number of methods (Penman, Turc, Jensen and Haise, Thornthwaite, and Blaney and Cridle).
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