Analysis of AET and yield predictions under surface and buried drip irrigation systems using the Crop Model PILOTE and Hydrus-2D

• Published in: Agricultural water management Vol. 98; no. 6; pp. 1033 - 1044
• Main Authors: Mailhol, Jean Claude, Ruelle, Pierre, Walser, Sabine, Schütze, Niels, Dejean, Cyril
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01-04-2011; Elsevier; Elsevier Masson
• Series: Agricultural Water Management
• Subjects: Actual evapotranspiration; Actual evapotranspiration Crop model Drip irrigation Hydrus-2D; Agricultural and forest climatology and meteorology. Irrigation. Drainage; Agricultural and forest meteorology; Agronomy. Soil science and plant productions; Biological and medical sciences; Computer simulation; Corn; Crop model; crop models; crop yield; Crops; Drip irrigation; Environmental Engineering; Environmental Sciences; Evapotranspiration; Fundamental and applied biological sciences. Psychology; General agronomy. Plant production; Hydrus-2D; Irrigation; irrigation management; Irrigation systems; loam soils; Loamy soils; Mathematical models; Mediterranean climate; microirrigation; soil water; spatial distribution; Water balance and requirements. Evapotranspiration; water stress; water uptake; Hydrus-2D; Actual evapotranspiration; Crop model; Drip irrigation; Vegetals; Prediction; Modeling; System; Microirrigation; Analysis; Evapotranspiration; Trickle irrigation; Water engineering; Models; Yield; Cultivated plant; IRRIGATION GOUTTE A GOUTTE; MODELE; CEREALE; EVAPOTRANSPIRATION
• ISSN: 0378-3774; 1873-2283
• DOI: 10.1016/j.agwat.2011.01.014

Innovative irrigation solutions have to face water scarcity problems affecting the Mediterranean countries. Generally, surface (DI) or subsurface drip irrigation systems (SDI) have the ability to increase water productivity (WP). But the question about their possible utilisation for crops such as corn would merit to be analysed using an appropriate economic tool. The latter would be necessary based on the utilisation of a modelling approach to identify the optimal irrigation strategy associating a water amount with a crop yield (Yc). In this perspective, a possible utilisation of the operative 1D crop model PILOTE for simulating actual evapotranspiration (AET) and yield under a 2D soil water transfer process characterizing DI and SDI was analysed. In this study, limited to a loamy soil cultivated with corn, the pertinence of the root water uptake model used in the numerical code Hydrus-2D for AET estimations of actual evapotranspiration (AET) under water stress conditions is discussed throughout the Yc
=
F(AET) relationship established by PILOTE on the basis of validated simulations. The conclusions of this work are (i): with slight adaptations, PILOTE can provide reliable WP estimations associated to irrigation strategies under DI and SDI, (ii): the current Hydrus-2D version used in this study underestimates AET, compared with PILOTE, in a range varying from 7% under moderate water stress conditions to 14% under severe ones, (iii): A lateral spacing of 1.6
m for the irrigation of corn with a SDI system is an appropriate solution on a loamy soil under a Mediterranean climate.
A local Yc
=
F(AET) relationship associated with a Hydrus-2D version taking into account the compensating root uptake process could result in an interesting tool to help identify the optimal irrigation system design under different soil conditions.