Abelardo A. Montenegro, Suzana M. Montenegro, Rae Mackay
Universidade Federal Rural de Pernambuco, Brasil
E-mail: Monte@hotlink.com.br

The economy of the Brazilian Northeast is still based on non-irrigated agriculture. Irregular rainfall and high evaporation rates require irrigation for crop development and dramatically reduce water resources during dry periods. When rainfall occurs, rates are usually high and water is lost by runoff. Alluvial deposit infiltration rates are usually high and reduce the surface loss by refilling the underground reserves.Quantitative and qualitative investigation have been carried out in an pilot irrigation project in an alluvial area in the semi-arid region of the Brazilian Northeast. Between the dry and the rainy season, seasonal water levels and salinity concentrations have been recorded. In general, salts are leached by the beginning of the rainy season, and salt concentration increases at the groundwater. By the end of the rainy season, salts are discharged from the deposit, and water resources are available for farming.