FIELD-SCALE ASSESSMENT OF NUTRIENT AND SOIL LOSSES DURING SURFACE RUNOFF EVENTS, IN AN OLTREPÒ PAVESE (SOUTHERN LOMBARDY ¿ ITALIAN REGION) VINEYARD HILL.

The aim of my Ph.D. work was to investigate sediment transport and nutrient content in runoff water from an agricultural system. The study was carried out in a representative sites of the Oltrep\uf2 Pavese, in Lombardy region (northern Italy) in a vineyard equipped with instruments for measuring volume and rate of runoff and collecting samples to determine the amount of soil loss related to each rainfall event. The site was equipped with a weather station, which included a recording rain gauge. The analysis was done under natural rainfall condition during the period December 2008 - December 2012, in which 15 rainfall events were recorded. The first step of the research was to equip the field plot with a collection system. An in-field runoff multislot collector, exploitable for monitoring nutrients, pesticides and sediments loadings in runoff, was installed in the field and was improved with a home made level reading system able to measure with high temporal resolution, the runoff rate variation. Subsequently every runoff event was investigated. Samples were taken and analysed for quantifying the sediments loaded from runoff event and the nutrient losses from the system. Samples were also analysed with a laser diffraction technique in order to characterize, in natural conditions, the distribution of sediment grain-size transported by rainfall runoff

Analisi del contenuto idrico del suolo per due differenti sistemi di irrigazione

L\u2019esigenza di attuare interventi mirati alla razionalizzazione della risorsa idrica \ue8 avvertita in modo specifico nel comparto agricolo, in considerazione dei notevolissimi volumi di acqua richiesti per il compimento del ciclo produttivo delle coltivazioni. La scelta del sistema di irrigazione risulta determinante per il contenimento delle perdite e il miglioramento dell\u2019efficienza d\u2019irrigazione. A tal proposito \ue8 stata condotta una sperimentazione in Pianura Padana su due appezzamenti per confrontare due differenti sistemi irrigui: per gravit\ue0 tramite scorrimento superficiale, e per aspersione con pivot ad ala imperniata. Il monitoraggio dei contenuti idrici \ue8 stato eseguito a diverse profondit\ue0, sia con un metodo diretto e discontinuo (metodo gravimetrico), sia con metodo indiretto e continuo, che accoppia la misura tensiometrica in campo, allo studio della curva di ritenzione idrica in laboratorio. La prova di campo ha dimostrato una maggiore perdita per percolazione nel sistema a scorrimento, confermando la bassa efficienza del metodo stesso e la necessit\ue0 di apportare maggiori volumi complessivi

Tecnica di misura dei fenomeni di ruscellamento superficiale

Il suolo \ue8 una risorsa non rinnovabile capace di assicurare funzioni essenziali non solo a livello ambientale ma anche sociale ed economico, assumendo quindi un ruolo centrale nel contesto di sostenibilit\ue0 dell\u2019agricoltura. Tuttavia il suolo \ue8 soggetto ad un continuo degrado dovuto in particolare al fenomeno dell\u2019erosione che non solo ne influenza negativamente le propriet\ue0 nutritive ma diventa una potenziale fonte di inquinamento per le acque superficiali. I fenomeni erosivi sono influenzati da notevoli fattori che il pi\uf9 delle volte vengono meglio descritti se studiati a scala di campo, piuttosto che a piccola scala. Inoltre gli alti costi degli strumenti e la quantit\ue0 enorme di ruscellato limitano il pi\uf9 delle volte il numero di siti che possono essere studiati. Sono stati quindi sperimentati strumenti, per parcelle di pi\uf9 ampia superficie, che permettono di ripartire l\u2019acqua ed il ruscellato e di ridurre in questo modo il campione raccolto mantenendolo rappresentativo. In questo lavoro viene presentata l\u2019applicazione pratica di uno di questi strumenti di misura opportunamente adattato che permette con ampia soluzione temporale di monitorare i fenomeni di ruscellamento superficiale a scala di campo

Chiral Random Matrix Theory and Chiral Perturbation Theory

Spontaneous breaking of chiral symmetry in QCD has traditionally been inferred indirectly through low-energy theorems and comparison with experiments. Thanks to the understanding of an unexpected connection between chiral Random Matrix Theory and chiral Perturbation Theory, the spontaneous breaking of chiral symmetry in QCD can now be shown unequivocally from first principles and lattice simulations. In these lectures I give an introduction to the subject, starting with an elementary discussion of spontaneous breaking of global symmetries.Comment: Lectures given as mini-course at the XIV Mexican School on Particles and Fields 201

Nuclear techniques and the particulate matter pollution in big harbours

The impact of big harbours on the air quality is an important issue both from the environmental and the economical point of view. The harbour of Genoa is the largest in Italy and one of the major ports of the Mediterranean. We have determined the fraction of Particulate Matter (PM) concentration in town due to the heavy oil combustion of the diesel engines of the vessels in the harbour. This turned out to be 12% in PM10 and 25% in PM2.5 and PM1, with about 85% of the PM from this source concentrated in particles with aerodynamic diameter, Dae < 1 μm. We could also point out a link between concentration peaks of the tracers of heavy oil combustion (V and Ni) and the ferryboats traffic. The key tool in this work was the coupling between particular sampling devices and some Ion Beam Analysis (IBA) techniques, in particular Particle Induced X-ray Emission (PIXE), which belong to the broader category of nuclear techniques in applied physics

Heavy-light mesons in the epsilon-regime

We study the finite-size scaling of heavy-light mesons in the static limit. We compute two-point functions of chiral current densities as well as pseudoscalar densities in the epsilon-regime of heavy meson Chiral Perturbation Theory (HMChPT). As expected, finite volume dependence turns out to be significant in this regime and can be predicted in the effective theory in terms of the infinite-volume low-energy couplings. These results might be relevant for extraction of heavy-meson properties from lattice simulations.Comment: 32 pages, 4 figure

Soot reference materials for instrument calibration and intercomparisons: A workshop summary with recommendations

Soot, which is produced from biomass burning and the incomplete combustion of fossil and biomass fuels, has been linked to regional and global climate change and to negative health problems. Scientists measure the properties of soot using a variety of methods in order to quantify source emissions and understand its atmospheric chemistry, reactivity under emission conditions, interaction with solar radiation, influence on clouds, and health impacts. A major obstacle currently limiting progress is the absence of established standards or reference materials for calibrating the many instruments used to measure the various properties of soot. The current state of availability and practicability of soot standard reference materials (SRMs) was reviewed by a group of 50 international experts during a workshop in June of 2011. The workshop was convened to summarize the current knowledge on soot measurement techniques, identify the measurement uncertainties and limitations related to the lack of soot SRMs, and identify attributes of SRMs that, if developed, would reduce measurement uncertainties. The workshop established that suitable SRMs are available for calibrating some, but not all, measurement methods. The community of users of the single-particle soot-photometer (SP2), an instrument using laser-induced incandescence, identified a suitable SRM, fullerene soot, but users of instruments that measure light absorption by soot collected on filters did not. Similarly, those who use thermal optical analysis (TOA) to analyze the organic and elemental carbon components of soot were not satisfied with current SRMs. The workshop, and subsequent, interactive discussions, produced a number of recommendations for the development of new SRMs, and their implementation, that would be suitable for the different soot measurement methods