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Validazione e calibrazione del modello SWAP attraverso il confronto con misure di contenuto idrico del terreno
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Monteleone M., Delivand M. K., Garofalo P., Cammerino A.R.B., 2015. Agronomic Management of Straw and Its Energy Use in a Long-Term Sustainability Perspective. Book chapter in: Handbook of Renewable Energy, Publisher: Springer-Verlag Berlin Heidelberg, Editors: Walter Leal Filho, pp.22. DOI: 10.1007/978-3-642-39487-4
No full textCaratterizzazione del clima di Foggia. Analisi di un cinquantennio di rilevazioni meteorologiche, dal 1951 al 2000.
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Application and evaluation of the SWAP model for simulating water and solute transport in a cracking clay soil
Full text linkIn Sicily, the increasing scarcity of quality water is leading to irriga- from salinization (Crescimanno et al., 2004).
tion with saline water in soils having a considerable susceptibility to In Sicily, the increasing scarcity of good quality water
cracking. Irrigation systems involving high application rates are used coupled with intensive use of soil under semiarid to arid
in these irrigated areas, and bypass flow during irrigation is thus climatic conditions, is leading to irrigation with saline
prevalent. Adoption of management practices accounting for cracking water on soils having a high shrink-swell potential and
is therefore necessary to prevent salinization and land degradation. susceptibility to cracking (Crescimanno and Provenzano,
In this paper, water flow and solute transport in a Sicilian cracking 1999). These soils are irrigated in the summer season,
soil irrigated with saline water was simulated by using the soil-water- when the cracks open up, by sprinkler systems, which inatmosphere-
plant environment (SWAP) model, and the simulated volve high application rates. Because of these high apresults
compared with measured values of soil moisture and salinity. plication rates, bypass flow, that is, the rapid transport
The soil hydraulic parameters were obtained by inverse method based of water and solutes via macropores or cracks to subsoil
on multi-step outflow experiments, adopting two different sets of hy- or to groundwater (Bouma, 1991; Crescimanno, 2001), draulic parameters/functions, that is, (i) the van Genuchten-Mualem, (VGM model) and (ii) the Brutsaert retention equation coupled with is prevalent during irrigation.
the hydraulic conductivity model proposed by Gardner (B-G model). Laboratory investigations performed on undisturbed
The results obtained using field measurements from four soil profiles soil columns sampled from these areas showed that saliof
a cracking clay soil showed that SWAP provided accurate predic- nization or leaching occurred during bypass flow dependtions
of water content, , when the soil hydraulic properties were ing on the concentration of the applied solution compared
expressed according to the B-G model. Using the B-G hydraulic pa- with the concentration of the pore solution (Crescimanno
rameters/functions, the model was calibrated with reference to the and De Santis, 2004); the efficiency of salt-leaching was
dispersivity (Ldis).Acalibration value of about 20 cm was found for the found to depend on crack volume (Crescimanno et al.,
four different profiles. In the conditions occurring in the Sicilian area 2002). The low values of the sodium adsorption ratio
where we are focusing our attention, the predictive errors associated (SAR) of irrigation water, and the low values of the exwith
the simulated ECsat, can be considered acceptable if the purpose changeable sodium percentage (ESP) measured in these
of application is to predict the influence of salinity on crop yield
Influenza di differenti volumi irrigui sulla produzione di pomodoro in ambiente mediterraneo
No full textGoing Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Management scenarios preventing salinization under irrigation with saline water.
No full textManagement scenarios aimed at optimizing irrigation in a Sicilian vineyard characterized by a cracking clay soil irrigated with saline water were explored for seven soil profiles (Baglio 1-Baglio 7), by using the simulation model soil-water-atmosphere-plant environment (SWAP), which accounts for shrinkage and cracking. Accurate prediction of water content, theta, was obtained for the seven profiles by expressing the soil hydraulic properties according to the Brutsaert retention equation coupled with the hydraulic conductivity model proposed by Gardner (B-G model). A satisfactory prediction of the electrical conductivity of saturated extract (ECsat) ad was obtained using for the dispersivity (L-dis), a calibration value of 20 cm. Different irrigation schedulings and alternating waters of different quality were then explored as viable management options. The results showed that bypass flow determined a favorable water distribution, and that the best irrigation strategy was to make a minimum number of irrigations, by maximizing at the same time the amount of water supplied at each irrigation. Water storage in cracks was found to promote salt-leaching; neglecting cracks and bypass flow was shown to overestimate salinization. Alternating two different irrigation waters proved to be the best strategy, which could be adopted to reduce soil salinization and enhance crop transpiration. Findings concerning the role of cracks in the process of salt-leaching suggested that, under field conditions, application of a leaching solution was more efficient if the soil presented a considerable degree of cracking
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