Modeling water resources of a highly irrigated alluvial plain (Italy): calibrating soil and groundwater models

Abstract

Modern and effective water management in large alluvial plains that have intensive agricultural activity requires the integrated modeling of soil and groundwater. The models should be complex enough to properly simulate several, often non-linear, processes, but simple enough to be effectively calibrated with the available data. An operative, practical approach to calibration is proposed, based on three main aspects. First, the coupling of two models built on wellvalidated algorithms, to simulate (1) the irrigation system and the soil water balance in the unsaturated zone and (2) the groundwater flow. Second, the solution of the inverse problem of groundwater hydrology with the comparison model method to calibrate the model. Third, the use of appropriate criteria and cross-checks (comparison of the calibration results and of the model outputs with hydraulic and hydrogeological data) to choose the final parameter sets that warrant the physical coherence of the model. The approach has been tested by application to a large and intensively irrigated alluvial basin in northern Italy.

Hybrid Inversion Method to Estimate Hydraulic Transmissivity by Combining Multiple-Point Statistics and a Direct Inversion Method

“…The CMM has been successfully applied in a number of case studies (e.g., Vassena et al, 2012;De Filippis et al, 2016), and beyond the field of hydrogeology (Lesnic, 2010). One of its strengths is computational efficiency, because at each iteration, one only has to solve a FP, and few iterations are needed to obtain a reliable T (est) in most cases.…”

A coupled human–natural system to assess the operational value of weather and climate services for agriculture

“…For this purpose, we rely on a spatially distributed process-based model of the Muzza irrigation district , which is composed of three interlaced modules: (i) a distributedparameter water balance module that simulates water resources, conveyance, distribution, and soil-crop water balance (Facchi et al, 2004;Gandolfi et al, 2006); (ii) a heat unit module that simulates the sequence of growth stages as a function of temperature (Neitsch et al, 2011); and (iii) a crop growth module that estimates the optimal and actual yields, accounting for the effects of water stresses due to the insufficient water supply that may have occurred during the agricultural season ). The water balance module partitions the irrigation district with a regular mesh of cells with a side length of 250 m, which was selected to properly reproduce the spatial distributions of all the modelled processes, especially in terms of water balance (Vassena et al, 2012). Each individual cell identifies a soil volume which extends from the soil surface to the lower limit of the root zone.…”

Modeling Groundwater Flow in Heterogeneous Porous Media with YAGMod

“…Further modifications were proposed by Ponzini and Crosta [20], Ponzini et al [26], Pasquier and Marcotte [27], Ponzini et al [28]. The CMM was applied to alluvial aquifers in Italy [14,16,21], Switzerland [22] and Canada [23,29,30] and to a carbonatic aquifer in southern Italy [17,31].…”

“…This method was originally proposed by Scarascia and Ponzini [18], successively developed by Ponzini and Lozej [19] and cast in a more formal mathematical framework by Ponzini and Crosta [20]. The CMM has been applied and implemented with success to study 2D hydraulic flow in regional aquifers [14,16,17,[21][22][23], and therefore, for the moment, its implementation within YAGMod covers these kinds of systems only.…”

“…Within this background, the first goal of this paper is to propose a code, YAGMod (yet another groundwater flow model), developed in Fortran90, for the simulation of constant-density, groundwater flow under stationary conditions, which is the extension of the codes developed by our research team over the years [7][8][9][10][11][12][13][14][15][16][17]. YAGMod is based on a conservative finite difference scheme for stationary conditions and is oriented to the simulation of flow in saturated media.…”