Caratterizzazione dei Paesaggi Agricoli Tradizionali italiani mediante modelli eco-idrologici e telerilevamento

L’ecoidrologia è la scienza fondamentale per la comprensione del legame esistente tra le dinamiche degli ecosistemi e il ciclo dell'acqua. L'obiettivo del presente lavoro di ricerca è la caratterizzazione da un punto di vista quantitativo dei processi eco-idrologici che regolano gli scambi di massa e di energia nel sistema suolo-pianta-atmosfera all’interno dei PAT (Paesaggi Agricoli Tradizionali) delle Ecoregioni d'Italia, mettendo così in luce l'impatto che il loro comportamento eco-idrologico esercita sulla multifunzionalità di tali sistemi (dalla produzione agraria al grado di protezione del territorio) e definendo alcuni “indicatori eco-idrologici” per le tipologie di paesaggio analizzate. Lo studio, condotto nell’ambito del progetto PRIN 2010-2011 sui “Paesaggi Agrari Tradizionali d’Italia”, ha riguardato l’estrazione di due tipologie di indicatori; un primo gruppo, ottenuto da dati di Osservazione della Terra (serie multi temporale con frequenza complessiva di 8 giorni dell’indice di vegetazione NDVI composite a 16 giorni, derivato dal sensore MODIS Terra ed Aqua) per caratterizzare la dinamica vegetazionale (vigore delle coperture vegetali, variazioni temporali (inter-annuali), indici bio-metrici caratteristici, stabilità nel tempo di particolari indici di sviluppo, statistiche vegetazionali). Un secondo gruppo di indicatori è stato derivato dall’applicazione di un modello eco-idrologico, per la stima dei flussi di evaporazione e di traspirazione (stimati mediante l’applicazione del modello P-M FAO56), della produzione primaria lorda (GPP) e netta (NPP), dell’insorgenza di condizioni di stress idrico e del contenuto idrico nel suolo (soil water content, SWC). Il modello eco-idrologico prende in conto come input forcing le condizioni di copertura vegetale (derivanti dal primo gruppo di eco-indicatori), il dato meteorologico (derivato da dati di ri-analisi ERA-Interim), le caratteristiche idrauliche del suolo, derivate da semplici funzioni di pedo-trasferimento (PTF) applicate ai prodotti Topsoil physical properties e Soil Organic Carbon Content dell’European Soil Data Centre (ESDAC). Alcuni parametri del modello sono stati derivati dal confronto con misure sperimentali nei siti di Castelvetrano (Oliveto in provincia di Trapani, PAT) e Brisighella (Actinidia in provincia di Ravenna, non-PAT)., Infine un ultimo indicatore è stato valutato con riferimento ai processi di erosione del suolo, in base al modello “RUSLE 2015” del JRS. I risultati ottenuti con risoluzione temporale giornaliera per il periodo 2003-2015 sono stati aggregati al fine di sintetizzare in maniera più efficace la risposta dei PAT nell’ambito dei processi eco-idrologici con lo scopo di migliorare la classificazione e la caratterizzazione dei PAT, nonché per individuare strategie di pianificazione e gestione del paesaggio

Harmonized Landsat 8 and Sentinel-2 Time Series Data to Detect Irrigated Areas: An Application in Southern Italy

Lack of accurate and up-to-date data associated with irrigated areas and related irrigation amounts is hampering the full implementation and compliance of the Water Framework Directive (WFD). In this paper, we describe the framework that we developed and implemented within the DIANA project to map the actual extent of irrigated areas in the Campania region (Southern Italy) during the 2018 irrigation season. For this purpose, we considered 202 images from the Harmonized Landsat Sentinel-2 (HLS) products (57 images from Landsat 8 and 145 images from Sentinel-2). Such data were preprocessed in order to extract a multitemporal Normalized Difference Vegetation Index (NDVI) map, which was then smoothed through a gap-filling algorithm. We further integrated data coming from high-resolution (4 km) global satellite precipitation Precipitation Estimation from Remotely Sensed Information using Artificial Neural Networks (PERSIANN)-Cloud Classification System (CCS) products. We collected an extensive ground truth in the field represented by 2992 data points coming from three main thematic classes: bare soil and rainfed (class 0), herbaceous (class 1), and tree crop (class 2). This information was exploited to generate irrigated area maps by adopting a machine learning classification approach. We compared six different types of classifiers through a cross-validation approach and found that, in general, random forests, support vector machines, and boosted decision trees exhibited the best performances in terms of classification accuracy and robustness to different tested scenarios. We found an overall accuracy close to 90% in discriminating among the three thematic classes, which highlighted promising capabilities in the detection of irrigated areas from HLS products

Statistical analysis of the volcano seismicity during the 2007 crisis of Stromboli, Italy: a 3-day oscillatory signal as onset of the activity

We analyze the volcano seismicity recorded during the 2007 eruption of Stromboli. Data-set is composed of the continuous recordings of a three-component broad-band seismometer and of a strainmeter. Starting from the characterization of the standard activity as a stationary phase of equilibrium, we investigate the non-equilibrium phase of the effusive process. A statistical analysis of the explosions reveals that the occurrence is always driven by a Poisson process as for the standard activity, even approaching the effusion phase, with the only difference in shortening the inter-times just during the effusion. A slightly different process can be advocated for the swarms of the explosions, because a maximum in the distribution of inter-times can be evidenced. Regarding the amplitudes of the explosion-quakes, they have a log-normal distribution until the effusion onset as in the standard Strombolian activity. The actual departure from that stationarity seems to be traced by an early deformative response at very long period. It appears as a transient oscillating signal characterized by a period of about three days that modulates the explosion amplitudes. In a conceptual organ pipe-like model it is related to the chocking of the pipe. The successive activity can be interpreted as the response of volcano to restore the equilibrium condition

The Long-Period seismicity before and during the volcanic crises: examples from two case studies

The Long-Period (LP) seismicity is common at active volcanoes and is usually modeled as due to pressurized magmatic fluids flowing through rock cavities. These signals are sensitive to the thermodynamic conditions of the magma-gas mixture in the shallow plumbing system and can thus be adopted as “detectors” of an impelling eruption. We found that at Stromboli (Italy) before and/or during recent volcanic crises the LP events can occur in swarms, which show different statistics, higher energy and shallower location than the stationary LP activity. We imputed the LP swarms to a quick depressurization (|ΔP|≥105 Pa) of the shallowest (<0.8 km) part of the conduit. At Shishaldin (Alaska) the 2004 eruption is anticipated by a migration towards the surface of the LP source, which moves from ~8 km to ≾5 km below the crater rim. By simple assumptions, we modeled this source change as produced by an increase of the confining pressure within the plumbing system of ~5x107 Pa, possibly induced by an upward migration of ~108-1010 kg of magma

Impact of the peptide wmr-k on dual-species biofilm candida albicans/klebsiella pneumoniae and on the untargeted metabolomic profile

In recent years, the scientific community has focused on the development of new antibiotics to address the difficulties linked to biofilm-forming microorganisms and drug-resistant infections. In this respect, synthetic antimicrobial peptides (AMPs) are particularly regarded for their therapeutic potential against a broad spectrum of pathogens. In this work, the antimicrobial and antibiofilm activities of the peptide WMR-K towards single and dual species cultures of Candida albicans and Klebsiella pneumoniae were investigated. We found minimum inhibitory concentration (MIC) values for WMR-K of 10 µM for K. pneumoniae and of 200 µM for C. albicans. Furthermore, sub-MIC concentrations of peptide showed an in vitro inhibition of biofilm formation of mono and polymicrobial systems and also a good biofilm eradication even if higher concentrations of it are needed. In order to provide additional evidence for the effect of the examined peptide, a study of changes in extracellular metabolites excreted and/or uptaken from the culture medium (metabolomic footprinting) in the poly-microbial association of C. albicans and K. pneumoniae in presence and absence of WMR-K was performed. Comparing to the untreated dual species biofilm culture, the metabolomic profile of the WMR-K treated culture appears significantly altered. The differentially expressed compounds are mainly related to the primary metabolic pathways, including amino acids, trehalose, pyruvic acid, glycerol and vitamin B6

Estimation of evapotranspiration and crop coefficients of tendone vineyards using multi-sensor remote sensing data in a mediterranean environment

The sustainable management of water resources plays a key role in Mediterranean viticulture, characterized by scarcity and competition of available water. This study focuses on estimating the evapotranspiration and crop coefficients of table grapes vineyards trained on overhead "tendone" systems in the Apulia region (Italy). Maximum vineyard transpiration was estimated by adopting the "direct" methodology for ETp proposed by the Food and Agriculture Organization in Irrigation and Drainage Paper No. 56, with crop parameters estimated from Landsat 8 and RapidEye satellite data in combination with ground-based meteorological data. The modeling results of two growing seasons (2013 and 2014) indicated that canopy growth, seasonal and 10-day sums evapotranspiration values were strictly related to thermal requirements and rainfall events. The estimated values of mean seasonal daily evapotranspiration ranged between 4.2 and 4.1 mm·d-1, while midseason estimated values of crop coefficients ranged from 0.88 to 0.93 in 2013, and 1.02 to 1.04 in 2014, respectively. The experimental evapotranspiration values calculated represent the maximum value in absence of stress, so the resulting crop coefficients should be used with some caution. It is concluded that the retrieval of crop parameters and evapotranspiration derived from remotely-sensed data could be helpful for downscaling to the field the local weather conditions and agronomic practices and thus may be the basis for supporting grape growers and irrigation managers

The identification of a novel Sulfolobus islandicus CAMP-like peptide points to archaeal microorganisms as cell factories for the production of antimicrobial molecules

Background: Pathogenic bacteria easily develop resistance to conventional antibiotics so that even relatively new molecules are quickly losing efficacy. This strongly encourages the quest of new antimicrobials especially for the treatment of chronic infections. Cationic antimicrobial peptides (CAMPs) are small positively charged peptides with an amphipathic structure, active against Gram-positive and Gram-negative bacteria, fungi, as well as protozoa.Results: A novel (CAMP)-like peptide (VLL-28) was identified in the primary structure of a transcription factor, Stf76, encoded by pSSVx, a hybrid plasmid-virus from the archaeon Sulfolobus islandicus. VLL-28 displays chemical, physical and functional properties typical of CAMPs. Indeed, it has a broad-spectrum antibacterial activity and acquires a defined structure in the presence of membrane mimetics. Furthermore, it exhibits selective leakage and fusogenic capability on vesicles with a lipid composition similar to that of bacterial membranes. VLL-28 localizes not only on the cell membrane but also in the cytoplasm of Escherichia coli and retains the ability to bind nucleic acids. These findings suggest that this CAMP-like peptide could exert its antimicrobial activity both on membrane and intra cellular targets.Conclusions: VLL-28 is the first CAMP-like peptide identified in the archaeal kingdom, thus pointing to archaeal microorganisms as cell factories to produce antimicrobial molecules of biotechnological interest. Furthermore, results from this work show that DNA/RNA-binding proteins could be used as sources of CAMPs

Peptide gH625 enters into neuron and astrocyte cell lines and crosses the blood-brain barrier in rats.

Peptide gH625, derived from glycoprotein H of herpes simplex virus type 1, can enter cells efficiently and deliver a cargo. Nanoparticles armed with gH625 are able to cross an in vitro model of the blood-brain barrier (BBB). In the present study, in vitro experiments were performed to investigate whether gH625 can enter and accumulate in neuron and astrocyte cell lines. The ability of gH625 to cross the BBB in vivo was also evaluated. gH625 was administered in vivo to rats and its presence in the liver and in the brain was detected. Within 3.5 hours of intravenous administration, gH625 can be found beyond the BBB in proximity to cell neurites. gH625 has no toxic effects in vivo, since it does not affect the maximal oxidative capacity of the brain or the mitochondrial respiration rate. Our data suggest that gH625, with its ability to cross the BBB, represents a novel nanocarrier system for drug delivery to the central nervous system. These results open up new possibilities for direct delivery of drugs into patients in the field of theranostics and might address the treatment of several human disease

Retrieval of evapotranspiration from sentinel-2: Comparison of vegetation indices, semi-empirical models and SNAP biophysical processor approach

Remote sensing evapotranspiration estimation over agricultural areas is increasingly used for irrigation management during the crop growing cycle. Different methodologies based on remote sensing have emerged for the leaf area index (LAI) and the canopy chlorophyll content (CCC) estimation, essential biophysical parameters for crop evapotranspiration monitoring. Using Sentinel-2 (S2) spectral information, this studyperformeda comparative analysis of empirical (vegetation indices), semi-empirical (CLAIR model with fixed and calibrated extinction coefficient) and artificial neural network S2 products derived from the Sentinel Application Platform Software (SNAP) biophysical processor (ANN S2 products) approaches for the estimation of LAI and CCC. Four independent in situ collected datasets of LAI and CCC, obtained with standard instruments (LAI-2000, SPAD) and a smartphone application (PocketLAI), were used. The ANN S2 products present good statistics for LAI (R2 > 0.70, root mean square error (RMSE) 0.75, RMSE < 0.68 g/m2) retrievals. The normalized Sentinel-2 LAI index (SeLI) is the index that presents good statistics in each dataset (R2 > 0.71, RMSE < 0.78) and for the CCC, the ratio red-edge chlorophyll index (CIred-edge) (R2 > 0.67, RMSE < 0.62 g/m2). Both indices use bands located in the red-edge zone, highlighting the importance of this region. The LAI CLAIR model with a fixed extinction coefficient value produces a R2 > 0.63 and a RMSE < 1.47 and calibrating this coefficient for each study area only improves the statistics in two areas (RMSE 0.70). Finally, this study analyzed the influence of the LAI parameter estimated with the different methodologies in the calculation of crop potential evapotranspiration (ETc) with the adapted Penman–Monteith (FAO-56 PM), using a multi-temporal dataset. The results were compared with ETc estimated as the product of the reference evapotranspiration (ETo) and on the crop coefficient (Kc) derived fromFAO table values. In the absence of independent reference ET data, the estimated ETc with the LAI in situ values were considered as the proxy of the ground-truth. ETc estimated with the ANN S2 LAI product is the closest to the ETc values calculated with the LAI in situ (R2 > 0.90, RMSE < 0.41 mm/d). Our findings indicate the good validation of ANN S2 LAI and CCC products and their further suitability for the implementation in evapotranspiration retrieval of agricultural areas

Activity of Free and Liposome-Encapsulated Essential Oil from Lavandula angustifolia against Persister-Derived Biofilm of Candida auris

The high virulence of Candida auris, a pathogen fungus considered as a global threat for public health, is due to its peculiar traits such as its intrinsic resistance to conventional antifungals. Its biofilm lifestyle certainly promotes the prolonged survival of C. auris after disinfection or antifungal treatments. In this work, for the first time, we detected persister cells in a biofilm of C. auris in a microwell plate model, following caspofungin treatment. Furthermore, we showed how persisters can progressively develop a new biofilm in situ, mimicking the re-colonization of a surface which may be responsible for recalcitrant infections. Plant-derived compounds, such as essential oils, may represent a valid alternative to combat fungal infections. Here, Lavandula angustifolia essential oil, as free or encapsulated in liposomes, was used to eradicate primary and persister-derived biofilms of C. auris, confirming the great potential of alternative compounds against emergent fungal pathogens. As in other Candida species, the action of essential oils against C. auris involves ROS production and affects the expression of some biofilm-related genes