WATER DISTRIBUTION IN SOILS WITH SUBSURFACE DRIP IRRIGATION SYSTEMS

Id:
4

Funder:
MINECO

Title:
WATER DISTRIBUTION IN SOILS WITH SUBSURFACE DRIP IRRIGATION SYSTEMS

Project Reference:
AGL2008-00153

Coordinator:
RODRIGUEZ SINOBAS LEONOR

Organisation:
UNIVERSIDAD POLITECNICA DE MADRID

Department:
DPTO. INGENIERIA RURAL

Centre:
ESCUELA TECNICA SUPERIOR DE INGENIEROS AGRONOMOS

Country:
SPAIN

SRIA Themes:
{sriathemes}

Start Date:
01/01/2009

End Date:
30/06/2013

Summary:
WATER AND ENERGY SAVINGS ARE GOALS OF PERMANENT - SUSTAINABLE IRRIGATED AGRICULTURE. A PRIORITY IN THE IMPROVEMENT AND MODERNIZATION OF IRRIGATION SYSTEM DESIGN AND MANAGEMENT, THAT AIM HAS FAVOURED CHANGES FROM TRADITIONAL TO DRIP IRRIGATION METHODS. FURTHER DEVELOPMENTS ARE EXPECTED WITH A TREND TOWARDS SUBSURFACE DRIP IRRIGATION (SDI), A VARIANT OF THE FORMER WITH POTENTIAL ADVANTAGES FOR REDUCING EVAPORATION AND FOR USING WASTEWATERS. MEASURING INFILTRATION WITH SDI IS COMPLEX AND IS NOT FREQUENTLY DONE NOR ITS EVOLUTION ALONG IRRIGATION CAMPAIGNS ATTENDED. ITS NEED TO KNOW IRRIGATION EFFICIENCY IS FREQUENTLY IGNORED. INSTEAD, ROUGH ESTIMATIONS OF A PERCENTAGE OF WATER VOLUMES ARE OFFERED. A KNOWLEDGE OF INFILTRATION VALUES AND THEIR COMPARISON WITH VALUES FROM OTHER IRRIGATION METHODS WOULD ALLOW IMPROVING PRECISE CRITERIA ABOUT SDI OPERATIONS AND ITS SUITABILITY FOR CERTAIN SOIL TYPES. IT IS THEN OF SOME INTEREST TO CHARACTERIZE WATER DISCHARGE FROM THEIR IRRIGATION SYSTEMS, WHICH HAVE A KNOWN INTERFERENCE IN THE INTERFACE BETWEEN PIPELINE HYDRAULICS AND SOIL INFILTRATION IN THE FIELD UNITS. A BETTER UNDERSTANDING OF PHYSICAL PRINCIPLES INVOLVED SHOULD LEAD TO IMPROVE IRRIGATION EFFICIENCY, TO REDUCE PERCOLATION OF WATER AND FERTILIZERS AND TO SAVE ENERGY. CRITERIA TO DETERMINE WATER USE EFFICIENCY DELIVERED FROM PRESSURE IRRIGATION NETWORKS WILL BE STUDIED. FIRST, ELEMENTS OF IRRIGATION SYSTEMS WILL BE TESTED UNDER LABORATORY AND FIELD CONDITIONS IN ORDER TO COMPARE AND SELECT ANALYTICAL (RATIONAL) PROCEDURES SUITABLE TO CHARACTERIZE THEIR PERFORMANCE. THEN, SIMULATION AND PREDICTION MODELS WILL BE DEVELOPED TO ESTIMATE WATER DISTRIBUTION FROM SDI UNITS. THESE MODELS WILL DETERMINE UNIFORMITY INDICES AND POTENTIAL EFFICIENCY FOR EACH WATER APPLICATION, WHICH WILL BE CONTRASTED WITH THOSE OBTAINED UNDER FIELD CONDITIONS. OBSERVED RESULTS WILL BE USED FOR CALIBRATION OF MODELS. FINALLY, PRESSURIZED IRRIGATION NETWORKS PERFORMANCE WILL BE SIMULATED UNDER DIFFERENT INLET PRESSURES IN ORDER TO DEVELOP ALTERNATE EVALUATION PROCEDURES AND TO OPTIMIZE DECISIONS. THE EFFECT OF REGULATION IN CONTROL DEVICES, IN PARTICULAR VARIABLE SPEED PUMPS AND HYDRAULICALLY OPERATED VALVES, WILL BE STUDIED FOR THEIR SELECTION TOWARDS A BETTER CONTROL OF CONDITIONS AND MANAGEMENT OF SDI PERFORMANCE, ATTENDING SOILS AND CROPS EVOLUTION ALONG IRRIGATION CAMPAIGNS.

Keywords:
CATCH CROPS COVER CROPS NITROGEN WATER SOIL QUALITY