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ResumenSe ha medido la distribución de la humedad en 20 suelos, en sistema enarenado en la comarca Campo de Dalías (Almería), regados por goteo y bajo cultivo de pimiento. Se utilizaron goteros de caudal 3l.h -1 con una densidad de 2 emisores.m -2 y un tiempo de riego de 30 minutos. Se ha encontrado que existe una gran heterogeneidad en las propiedades físicas de los suelos a pesar de tratarse de suelos artificialmente aportados. El factor más importante para explicar las diferencias en la distribución de humedad fue la textura del suelo. De los ensayos se deduce que existen problemas en la distribución del riego debido a la presencia de horizontes impermeables. Por otra parte los niveles de humedad encontrados antes de los riegos sugieren que se está regando en exceso los suelos y que el área mojada alcanza a casi la totalidad de la superficie de cultivo. AbstractWe measured the moisture distribution in 20 soils under "arenado" system in the county Campo de Dalías (Almeria), drip irrigated and a pepper crop. Flow drippers 3l.h -1 were used with a density of 2 emiters.m -2 and a run time of 30 minutes. It has been found that there is great heterogeneity in the physical properties of soils despite being artificially supplied ones. The most important factor in explaining differences in moisture distribution was the soil texture. Trials it appears that there are problems in the distribution of irrigation due to the presence of impermeable layers. Moreover moisture levels found prior to suggest that the soils are being watered excessively and the wet area reaches almost the entire culture surface.

Several procedures for obtaining rainfall intensity-duration-frequency (IDF) relationships for storm durations ranging from 10 min to 24 h and for several return periods were analyzed. The data recorded for the period 1966-1997 are from five different locations in southern Spain: one mountain, two inland, and two littoral stations. We analyzed the original equations of Wenzel, Bell, Chen and Témez, and other ones modified from the last two. The first step was to determine the parameters of each equation for each geographical location. Subsequently, the coefficient of variation (CV) and index of agreement (i a ) of each equation were calculated in order to compare their estimations for rainfall durations of less than 2 h and less than 24 h. The results show that there is not one equation which is best suited for all the geographical areas or rainfall durations. The reference method, Wenzel's equation, is the best for rainfall periods of less than 24 h, but only for the littoral and inland geographical areas. If Wenzel's equation is not taken into account, the modified Témez equation proved to be the best at generating series for mountain areas and for the two rainfall periods studied. Therefore, in a regional study of rainfall durations of less than 24 h, where only 24 h data are available, and with littoral, inland and mountain areas, the modified Témez equation is strongly recommended.

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