Hydrological and hydraulic behaviour of a surface flow constructed wetland treating agricultural drainage water in northern Italy

A surface flow constructed wetland (SFCW) treating agricultural drainage water was investigated with the aim to detect modifications in hydrological and hydraulic characteristics after more than a decade of operation. Ponded infiltration tests were conducted to estimate the saturated hydraulic conductivity, Ks, of the surface soil layer at the point scale. At the global scale, infiltration rate, i, was computed from the water balance to detect leakages from the pervious wetland surface. Tracer tests were conducted to analyse the existence of preferential flow inside the system and to estimate its hydraulic retention time (HRT). Clogging phenomena occurred given a mean Ks value of 30 mm h 121 was measured near the SFCW inlet, that was 9.61 times lower than the value at the outlet zone. The estimated infiltration losses were two orders of magnitude lower than infiltration measured at the point scale. The results also confirmed the existence of a moderate amount of preferential flow paths and dead zones in the SFCW as the actual HRT (6.7 days) was shorter than the nominal one (8.1 days). Despite this, it can be concluded that the system performance is still good after 17 years of operation

Hydrological and hydraulic behaviour of a surface flow constructed wetland treating agricultural drainage water in northern Italy

A surface flow constructed wetland (SFCW) treating agricultural drainage water was investigated with the aim to detect modifications in hydrological and hydraulic characteristics after more than a decade of operation. Ponded infiltration tests were conducted to estimate the saturated hydraulic conductivity, Ks, of the surface soil layer at the point scale. At the global scale, infiltration rate, i, was computed from the water balance to detect leakages from the pervious wetland surface. Tracer tests were conducted to analyse the existence of preferential flow inside the system and to estimate its hydraulic retention time (HRT). Clogging phenomena occurred given a mean Ks value of 30 mm h-1 was measured near the SFCW inlet, that was 9.61 times lower than the value at the outlet zone. The estimated infiltration losses were two orders of magnitude lower than infiltration measured at the point scale. The results also confirmed the existence of a moderate amount of preferential flow paths and dead zones in the SFCW as the actual HRT (6.7 days) was shorter than the nominal one (8.1 days). Despite this, it can be concluded that the system performance is still good after 17 years of operation

Nuovi parametri per l'irrigazione di Abate F\ue9tel su vari cotogni

Riassunto La ricerca ha lo scopo di valutare l\u2019effetto della riduzione degli apporti irrigui sulle performance fisiologiche ed agronomiche della cultivar Abate Fet\ue9l innestata sui 4 portinnesti pi\uf9 comunemente utilizzati nella Valle del Po. La prova \ue8 stata effettuata presso l\u2019azienda agricola dimostrativa \u201cFondazione per l\u2019Agricoltura Fratelli Navarra\u201d sita in Ferrara, Emilia Romagna, mettendo a confronto quattro differenti portinnesti e densit\ue0 di impianto: MC, Sydo, Adams ed MH. Le 4 combinazioni sono state sottoposte ai seguenti 4 livelli di irrigazione decrescenti:100%, 50%, 25% RDI-IRRINET, test asciutto. L\u2019irrigazione \ue8 stata gestita seguendo un bilancio idrico secondo il modello IRRINET fornito dal Consorzio per il Canale Emiliano Romagnolo (CER), che tiene conto del regime di Deficit di irrigazione controllato (RDI). Il bilancio idrico del modello IRRINET ha confermato la propria validit\ue0 nella stima dell\u2019umidit\ue0 del terreno, avendo registrato una buona corrispondenza con i valori di umidit\ue0 misurati dai sensori disposti nella prova. I dati produttivi medi del biennio, relativi alla fase di piena produzione, inoltre, hanno evidenziato che il cotogno C, abbinato a forme di allevamento e impianti superfitti (12.000 piante/ha), deprime la pezzatura in misura significativa rispetto agli altri portinnesti, con un conseguente calo di prodotto commerciale. Summary This three-year trial is carried out at the Demonstration Farm of the \u201cFondazione per l'Agricoltura Fratelli Navarra\u201d located near Ferrara, Emilia-Romagna. On Abb\ue9 F\ue9tel grafted on 4 of the most currently used rootstocks in the Po Valley (MC, Sydo, Adams and MH) contrasting irrigation volumes are assessed, in each phenological stage and scion/rootstock combination, to determine the minimum irrigation level at which plants are not exposed to damaging water stress conditions. The different volumes were determined as fractions of the IRRINET daily recommendation for Regulated Deficit Irrigation (RDI) in this orchard, and various agronomic parameters were determined. The IRRINET model proved suited to predict soil water content; decreasing irrigation volumes determined decreasing % of marketable yields, and diminishing fruit size, while total yields were not decreasing (for some rootstocks) between 100 and 50% IRRINET. MC performance was generally lower than for the other rootstocks, revealing the limits of its quite low vigour

Microclimatic physiological and productive effect of the overcanopy irrigation in an apple orchard

To test the efficacy and sustainability of evaporative cooling, two blocks of a commercial 'Fuji' apple orchard in Medelana (Ferrara, Italy) were subjected to two irrigation regimes: drip irrigation alone (DRI) or, between July and August (the hottest period of the year), supplemented by overcanopy irrigation (OCI). Stem/leaf water potential, leaf gas exchange where performed the day before, soon after and the day after OCI, along the growing season. Daily fruit growth, leaf and fruit temperature and microclimatic parameters within the blocks where monitored for the entire experiment. No difference was found in leaf/stem water potentials and leaf gas exchanges the day prior and after OCI. Photosynthesis, transpiration and stomatal conductance were improved on the OCI day. Also, fruit growth increased only on the OCI day, with higher rates all day long, but no further effects in the following days. Leaf, fruit temperature and microclimatic measurements within the blocks were only affected during OCI. Yield data show no difference between the two irrigation regimes. OCI in the environment tested affects tree performance only during application and a few hours afterwards. This management practice reduces water use efficiency resulting in more water applied per ton of fruit, likely a result related to the hot and humid climate of the Ferrara province

Noce: ridurre apporti idrici e nutrizionali senza danneggiare la produzione

Una sperimentazione triennale evidenzia l’adattabilità di questa coltura agli ambienti emiliano-romagnol

Multiple image deblurring with high dynamic-range Poisson data

An interesting problem arising in astronomical imaging is the reconstruction of an image with high dynamic range, for example a set of bright point sources superimposed to smooth structures. A few methods have been proposed for dealing with this problem and their performance is not always satisfactory. In this paper we propose a solution based on the representation, already proposed elsewhere, of the image as the sum of a pointwise component and a smooth one, with different regularization for the two components. Our approach is in the framework of Poisson data and to this purpose we need efficient deconvolution methods. Therefore, first we briefly describe the application of the Scaled Gradient Projection (SGP) method to the case of different regularization schemes and subsequently we propose how to apply these methods to the case of multiple image deconvolution of high-dynamic range images, with specific reference to the Fizeau interferometer LBTI of the Large Binocular Telescope (LBT). The efficacy of the proposed methods is illustrated both on simulated images and on real images, observed with LBTI, of the Jovian moon Io. The software is available at http://www.oasis.unimore.it/site/home/software.html