Resumen de La salinidad de los ríos Riguel-Arba ante futuros escenarios en los regadíos de Bardenas (Zaragoza): modelización geoquímica
Jesús Causapé Valenzuela, Luis Francisco Auqué Sanz, María José Gimeno Serrano, Juan Miguel A. Mandado Collado, Dolores Quílez Sáez de Viteri, Ramón Aragüés Lafarga
This work diagnoses the present salinity of the Riguel and Arba rivers (Spain) and predicts its expected evolution using geochemical models applied to the modernization of the actual Bardenas I and the completion of irrigation in the Bardenas II irrigation districts. The results show a progressive increase in salinity (from 0.39 to 2.21 dS/m electrical conductivity) in the Riguel-Arba system, due to the cumulative collection of irrigation return flows and its progression towards more saline facies. The Bardenas I modernization, involving an increase in irrigation efficiency from 50% to 90%, will decrease the volume and salinity of the Riguel River by 30%. In contrast, irrigation of the new 24000 ha Bardenas II land will increase the flow (12%) and salinity (21%) of the Arba River. Geochemical models may help in providing sensible estimates on the impact of irrigation on the salinity of the receiving water bodies.