44 research outputs found

    remote sensing supports the definition of the water quality status of lake omodeo italy

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    AbstractLake Omodeo is the largest artificial reservoir of Sardinia and its waters are a valuable resource for irrigation, domestic and industrial purposes. Lake Omodeo has serious problems of eutrophication. Since 2007 the local water authority has been undertaken a monitoring program designed to test an integrated methodology based on field measurements and remote sensing. This study illustrates the production of multitemporal spatialised maps of chlorophyll-a concentrations from satellite data acquired from Medium Resolution Imaging Spectrometer (MERIS). The analysis confirmed the eutrophic status of Omodeo. especially between spring and summer (mainly due to cyanobacteria bloom) assessing their dependency on weather conditions and river inputs

    Osservazione delle zone marine costiere da dati ottici multi-sensore: il caso studio della foce del Volturno

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    Questo lavoro s’inserisce nell’ambito del progetto bandiera RITMARE (Ricerca ITaliana per il MARE, 2012-2016, MIUR-CNR) che ha lo scopo di studiare, monitorare, gestire e valorizzare la risorsa marina in Italia. A tale fine il telerilevamento è parte integrante al progetto che, in questo studio, viene applicato alla fascia costiera della foce del Volturno. Lo studio si avvale dell’utilizzo di immagini satellitari (RapidEye (2013) e Landsat-8 OLI (2014)) e aviotrasportate (MIVIS (2011)). A supporto dell’analisi delle immagini sono state acquisite misure in-situ di riflettanza e di concentrazione dei seguenti parametri: clorofilla-a (Chl-a), sedimenti totali sospesi (TSM) e sostanza organica colorata disciolta (CDOM) durante una campagna svoltasi in agosto 2014. I dati telerilevati, geocodificati e co-registrati, sono stati pre-elaborati per correggere gli effetti radiometrici ed atmosferici. Le immagini sono state successivamente elaborate per classificare le acque marino-costiere secondo diversi gradi di complessità ottica e per produrre mappe di concentrazione di Chl-a, TSM e CDOM. In particolare, per la generazione delle mappe è stato applicato un approccio semi-empirico basato su analisi di correlazione dei dati in-situ; in particolare tra valori spettrali di riflettanza (es. rapporti di banda) e le corrispondenti misure di concentrazione di Chl-a, TSM e CDOM. I risultati mostrano un gradiente crescente di complessità ottica delle acque spostandosi dalle zone pelagiche verso le aree costiere. In queste aree l’analisi del dato OLI ha mostrato una variabilità spaziale di Chl-a, TSM e CDOM imputabile ai regimi idrologici del fiume Volturno

    multitemporal analysis of algal blooms with meris images in a deep meromictic lake

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    MERIS images (2003-2011) were used to detect algal bloom events in Lake Idro (Northern Italy) applying a semi-empirical algorithm. From the study of an intense phenomenon occurred in late summer 2010, a retrospective analysis of similar events during late summer/ early autumn period was performed. High intra- and inter-annual variability was observed and three additional bloom events were identified on 2003, 2005 and 2008. Hydrological and weather parameters were examined at different temporal intervals (August-October, September-October and monthly from August to October) to investigate the regulating factors of bloom incidence. Rather low temperatures and the persistence of clouds seem t

    Measuring freshwater aquatic ecosystems: The need for a hyperspectral global mapping satellite mission

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    AbstractFreshwater ecosystems underpin global water and food security, yet are some of the most endangered ecosystems in the world because they are particularly vulnerable to land management change and climate variability. The US National Research Council's guidance to NASA regarding missions for the coming decade includes a polar orbiting, global mapping hyperspectral satellite remote sensing mission, the Hyperspectral Infrared Imager (HyspIRI), to make quantitative measurements of ecosystem change. Traditionally, freshwater ecosystems have been challenging to measure with satellite remote sensing because they are small and spatially complex, require high fidelity spectroradiometry, and are best described with biophysical variables derived from high spectral resolution data. In this study, we evaluate the contribution of a hyperspectral global mapping satellite mission to measuring freshwater ecosystems. We demonstrate the need for such a mission, and evaluate the suitability and gaps, through an examination of the measurement resolution issues impacting freshwater ecosystem measurements (spatial, temporal, spectral and radiometric). These are exemplified through three case studies that use remote sensing to characterize a component of freshwater ecosystems that drive primary productivity. The high radiometric quality proposed for the HyspIRI mission makes it uniquely well designed for measuring freshwater ecosystems accurately at moderate to high spatial resolutions. The spatial and spectral resolutions of the HyspIRI mission are well suited for the retrieval of multiple biophysical variables, such as phycocyanin and chlorophyll-a. The effective temporal resolution is suitable for characterizing growing season wetland phenology in temperate regions, but may not be appropriate for tracking algal bloom dynamics, or ecosystem responses to extreme events in monsoonal regions. Global mapping missions provide the systematic, repeated measurements necessary to measure the drivers of freshwater biodiversity change. Archival global mapping missions with open access and free data policies increase end user uptake globally. Overall, an archival, hyperspectral global mapping mission uniquely meets the measurement requirements of multiple end users for freshwater ecosystem science and management

    FOOD2GATHER: What is migrants’ food all about in Europe? A media discourse analysis through the lens of controversies

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    This report is part of the HERANET funded project FOOD2GATHER. The project aims at understanding the question of integration/exclusion of migrants through foodscapes. An important step in this direction is to analyse the contextual framework within which food-related practices, norms and values are embedded in European societies. Food controversies that have raised and have been reported in the media since the “2015 migrants’ crisis” across Europe can reveal important aspects related to such norms and values and indicate possible tensions and compromises. This report presents and discusses relevant food controversies that occurred in the six countries participating in the study (Belgium, France, Germany, Italy, Norway, and the Netherlands). This will generate a contextual overview of the integration/exclusion of migrants through foodscapes. Controversy has been used as a tool and a scanner. Each of the six FOOD2GATHER teams provided two relevant controversies that have reached media attention in the last ten years. One of the two had to be related to halal food. The analysis of the controversies has been conducted by identifying issues they tackled, agents they involved, (public) spaces and situations in which controversies took place and what they produced. A comparative analysis of relevant variables related to migrations, such as the geopolitical position of the countries, organization of reception and food provision, has been conducted as well. The six countries included in the study have different traditions related to migration and have been exposed to the “migrants’ crisis” in different ways. These differences are reflected in the proposed controversies. However, some common traits tend to emerge and reveal power relationships within societies that are different or shared by the countries involved in the project. We show that these power relationships particularly deal with the right to food, citizens’ commitment, identity, the place of religion, animal welfare and political issues. Our study indicates that analysing controversies adds an important dimension to the study of foodscapes. Food controversies that reach the media attention are seldom something migrants have brought up themselves. The migrants’ representation in the media based on food controversies indicated that migrants are given little opportunity to negotiating values and practices, as norms about “the right” quantity and quality of food tend to reproduce the food model of the country they migrate to, also when there is a “positive” focus on ethnic business. To better understand these dynamics, we propose the concept of “food encounters” and illustrate how the type of food encounters can play a role in how foodscapes could evolve or even emerge.Consumption Research Norway (SIFO), OsloMe

    COVID-19 Severity in Multiple Sclerosis: Putting Data Into Context

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    Background and objectives: It is unclear how multiple sclerosis (MS) affects the severity of COVID-19. The aim of this study is to compare COVID-19-related outcomes collected in an Italian cohort of patients with MS with the outcomes expected in the age- and sex-matched Italian population. Methods: Hospitalization, intensive care unit (ICU) admission, and death after COVID-19 diagnosis of 1,362 patients with MS were compared with the age- and sex-matched Italian population in a retrospective observational case-cohort study with population-based control. The observed vs the expected events were compared in the whole MS cohort and in different subgroups (higher risk: Expanded Disability Status Scale [EDSS] score > 3 or at least 1 comorbidity, lower risk: EDSS score ≤ 3 and no comorbidities) by the χ2 test, and the risk excess was quantified by risk ratios (RRs). Results: The risk of severe events was about twice the risk in the age- and sex-matched Italian population: RR = 2.12 for hospitalization (p < 0.001), RR = 2.19 for ICU admission (p < 0.001), and RR = 2.43 for death (p < 0.001). The excess of risk was confined to the higher-risk group (n = 553). In lower-risk patients (n = 809), the rate of events was close to that of the Italian age- and sex-matched population (RR = 1.12 for hospitalization, RR = 1.52 for ICU admission, and RR = 1.19 for death). In the lower-risk group, an increased hospitalization risk was detected in patients on anti-CD20 (RR = 3.03, p = 0.005), whereas a decrease was detected in patients on interferon (0 observed vs 4 expected events, p = 0.04). Discussion: Overall, the MS cohort had a risk of severe events that is twice the risk than the age- and sex-matched Italian population. This excess of risk is mainly explained by the EDSS score and comorbidities, whereas a residual increase of hospitalization risk was observed in patients on anti-CD20 therapies and a decrease in people on interferon

    SARS-CoV-2 serology after COVID-19 in multiple sclerosis: An international cohort study

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    DMTs and Covid-19 severity in MS: a pooled analysis from Italy and France

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    We evaluated the effect of DMTs on Covid-19 severity in patients with MS, with a pooled-analysis of two large cohorts from Italy and France. The association of baseline characteristics and DMTs with Covid-19 severity was assessed by multivariate ordinal-logistic models and pooled by a fixed-effect meta-analysis. 1066 patients with MS from Italy and 721 from France were included. In the multivariate model, anti-CD20 therapies were significantly associated (OR = 2.05, 95%CI = 1.39–3.02, p < 0.001) with Covid-19 severity, whereas interferon indicated a decreased risk (OR = 0.42, 95%CI = 0.18–0.99, p = 0.047). This pooled-analysis confirms an increased risk of severe Covid-19 in patients on anti-CD20 therapies and supports the protective role of interferon

    A Satellite-Based Tool for Mapping Evaporation in Inland Water Bodies: Formulation, Application, and Operational Aspects

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    With the increase of evaporation projected for water bodies worldwide, there is a growing need for flexible and low data-demanding tools enabling the monitoring and management of water resources. This study presents a simple satellite-based tool named LakeVap specifically designed for mapping evaporation from lakes and reservoirs. LakeVap requires a small amount of potentially available data with a global coverage. The tool follows a Dalton-type approach and produces instantaneous (i.e., hourly) and daily evaporation maps from satellite-derived Lake Surface Water Temperature (LSWT) maps and single-point/gridded meteorological data. The model is tested on Lake Garda, Italy, by using a long time series of LSWT (ESA CCI-Lakes) and different sources of meteorological forcing. The accuracy of LakeVap evaporation outputs is checked by comparison with those from a hydro-thermodynamic model (Delft3D) specifically set up and validated for the case study. Results are consistent and sensitive to the representativeness of the meteorological forcing. In the test site, wind speed is found to be the most spatially variable parameter, and it is significantly underestimated by the ERA5 meteorological dataset (up to 100%). The potential application of LakeVap to other case studies and in operational contexts is discussed
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