That means only 3% of the "
effective rainfall", as it is termed, is used for public water supply.
The precipitation data with 4 km high spatial resolution and correction for elevation were considered suitable for the requirements of precipitation system analysis over high mountain areas and for determining
effective rainfall areas.
Effective rainfall ([P.sub.e]) was calculated from the formulae
The third objective of this work is to evaluate the use of
effective rainfall (instead of total rainfall) to establish correlations with water table time series and to test the possible advantage of this dataset corrected from evapotranspiration.
The
effective rainfall was estimated by the methodology of the Soil Conservation Service of the United States (USDA), available in the software Cropwat v.
Only precipitation events larger than 10 mm were considered as
effective rainfall events (Moret and Arrue 2007).
The key parameters calculated from the monitored data included
effective rainfall, evapotranspiration, irrigation interval, irrigation depth and irrigation index.
LL is the liquid irrigation depth (mm [day.sup.-1]); ETc is the crop evapotranspiration (mm [day.sup.-1]) of each treatment (Equation 2); and Pe is the
effective rainfall (mm [day.sup.-1]).
thought that it was appropriate to calculate the coefficient using
effective rainfall, and topsoil, groundwater level, and other factors should be fully considered.
Water inputs to the root zone include
effective rainfall (the fraction of total rain that infiltrates the soil after losses to leaf interception, surface runoff and depression storage, and evaporation) and irrigation (vineyard only).
The
effective rainfall is the portion of total rainfall that is useful for crop production.