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Zooplankton as refuge for invading bacteria
Get PDFNonetheless, studies on the impact of non-parasitic bacteria are still scarce. In this study we analysed the consequences of this colonisation on the distribution of potentially pathogenic and antibiotic resistant bacteria in freshwater systems. This is based on the hypothesis that potential pathogens have a selective advantage when growing in biofilms, as has been shown in clinical settings. Thus we postulate that attaching to animals might allow potential pathogens, e.g. deriving from the efflux of a waste water treatment plant (WWTP), to survive in freshwaters. Additionally the movement of the animal transports the bacteria away from the point-contamination to more pristine waters. We experimentally show that, if added to a natural bacterial community, Escherichia coli attaches to daphnids and derives particularly well in the gut of the animals, where they naturally do not form part of their microflora, whilst decreasing in abundance in the surrounding water. Moreover, the presence of daphnids decreased the abundance of a tetracycline resistance gene (tetA) in the surrounding water, whilst a higher number of tetA gene copies were detected in the animals. In addition we tested whether zooplankton species form a surface for the horizontal gene transfer, of e.g. antibiotic resistant genes, from one E. coli strain to another. In order to expand our hypothesis to natural environment we sampled Lake Maggiore at three points with increasing distance to an inflow of a WWTP and compared the microbial community on various zooplankton species as well as on stones and in the sediment. Whereas similar relationships have been described in marine systems, e.g. Vibrio cholera and Copepods, this is the first study that confronts the potential role of zooplankton in the spread of potential pathogens in freshwater systems
Distribution and origin of Thaumarchaea in the deep hypolimnion of Lake Maggiore
Get PDFThaumarchaea represents one of the most abundant groups of Archaea on Earth, being found in a variety of environments including soils, oceans, and freshwaters. Ammonia-oxidizing Thaumarchaea (AOA) significantly contribute to the global nitrogen and carbon cycle through chemolithoautotrophic oxidation of reduced nitrogen compounds. Their distribution of in freshwaters is still far less known than in marine and terrestrial environments. In this study, we analyzed the diversity and relative abundance of AOA in the deepest layers of the oligotrophic Lake Maggiore, confirming previous published results of AOA presence and showing spatial but no seasonal trends with respect to Bacteria. A high resolution at the Thaumarchaea community level was reached with the probe MGI-535 specifically designed in this study and applied for CARD-FISH analysis. Furthermore, phylogenetic analysis of AOA clone libraries from deep lake water and from the lake tributary, River Maggia, suggested the riverine origin of AOA of the deep hypolimnion of the lake
Ammonium thiosulphate assisted phytoextraction of mercury and arsenic in multi-polluted industrial soil
Get PDFThe possibility of using ammonium thiosulphate in assisted phytoextraction was evaluated on a greenhouse scale (mesocosm) for the simultaneous removal of mercury and arsenic from multi-polluted industrial soil. The addition of thiosulphate to the soil greatly promoted the uptake and translocation of both contaminants in the aerial parts of Brassica juncea and Lupinus albus. Thiosulphate showed great potential since it is a common fertilizer used to promote plant growth and is able to promote plant uptake of both Hg and As. Hg concentration in the aerial part of the plants reached 867 mg kg-1 in B. juncea and 114 mg kg-1 in L. albus. In the aerial parts, As concentration was about 9 mg kg-1 in B. juncea and 20 mg kg-1 in L. albus. This thus increases the applicability of phytoextraction in terms of cost and time especially if the remedial targets are based on bioavailable metal concentrations
Benefits and limitations of an intercalibration of phytoplankton assessment methods based on the Mediterranean GIG reservoir experience
No full textThe status of European legislation regarding inland water quality after the enactment of the Water Framework Directive (WFD) originated scientific effort to develop reliable methods, primarily based on biological parameters. An important aspect of the process was to ensure that quality assessment was comparable between the different Member States. The Intercalibration process (IC), required in the WFD ensures the unbiased application of the norm. The presented results were developed in the context of the 2nd IC phase. An overview of the reservoir type definition of the Lake Mediterranean Geographical Intercalibration Group, where four types were considered divided by both alkalinity and climate, togetherwith the results for selection of MaximumEcological Potential sites (MEP) are presented. MEP reservoirs were selected based on pressure and biological variables. Three phytoplankton-based assessment methods were intercalibrated using data from Mediterranean countries. The Mediterranean Assessment System for Reservoirs Phytoplankton (Spain), the New Mediterranean Assessment System for Reservoirs Phytoplankton (Portugal and Cyprus) and the New Italian Method (Italy) were applied. These three methods were compared through option 3 of the Intercalibration Guide. The similarity of the assessments was quantified, and the Good/Moderate (GM) boundaries assessed. All three methods stood as comparable at the GM boundary except for theMASRP in siliceous wet reservoirs, which was slightly stricter. Finally, the main taxonomic groups represented in the phytoplankton community atMEP conditionswere identified, as well as theirmain changes with an increasing trophic status.MEP sites are dominated by chrysophytes in siliceous wet reservoirs and by the diatoms Cyclotella and Achnanthes in calcareous ones. Cyanobacteria take over the community in both calcareous and siliceous wet reservoirs as eutrophication increases. In summary, the relevance and reliability of the quality assessment methods compared were confirmed both from an ecological perspective and a health risk management point of view
I laghi d\u27alta quota: indagare l\u27invisibile
No full textNot availableBreve descrizioni delle diverse caratteristiche dei laghi alpini e di come queste si modificano in relazione ai cambiamenti climatic
L\u27acqua nelle Terre Alte: una risorsa tra biodiversit? e sfruttamento da parte dell\u27uomo
No full textNot availableL\u27acqua ? una risorsa fondamentale per la vita dell\u27uomo e per l\u27esistenza degli organismi presenti sul pianeta. Tuttavia secondo la visione antropocentrica e utilitaristica dominante l\u27acqua ? considerata un elemento ?vuoto?, una risorsa da consumare per placare la sete, per la produzione di energia, per l\u27utilizzo nell\u27industria, inesauribile. Solo recentemente, sebbene ancora in misura nettamente minoritaria, si sta facendo strada l\u27idea che l\u27acqua di laghi e fiumi sia un elemento fondamentale per la vita di un gran numero di altri organismi che svolgono un ruolo decisivo e insostituibile per il funzionamento degli ecosistemi. L\u27acqua dunque ha valore, e non solo perch? pu? essere utilizzata dall\u27uomo, ma anche perch? ? sorgente di diversit? biologica (Biodiversit?) riconosciuta in se stessa come un valore. Tra gli organismi acquatici, i pesci sono quelli pi? noti anche ai non esperti ai lavori, probabilmente per la loro maggior visibilit? rispetto agli organismi pi? piccoli, e possono essere presi a titolo di esempio per capire la complessit? delle relazioni che possono intercorrere tra il mondo degli uomini e la risorsa acquatica. I pesci di laghi e fiumi sono infatti al centro di molteplici interessi quali la pesca commerciale e ricreativa, la gastronomia locale, il turismo, ma anche, in quanto organismi viventi, sono parte costituente la biodiversit? degli ambienti acquatici. Indirettamente poi sono toccati dall\u27uso dell\u27acqua e dagli utilizzi del territorio intorno a fiumi e laghi, che condizionano la struttura degli habitat ripariali ed acquatici e la qualit? delle acque stesse. In questi paragrafi affronteremo brevemente il tema della gestione degli ecosistemi acquatici con un particolare focus sul rapporto tra uomo e fauna ittica. Si porter? all\u27attenzione del lettore l\u27esperienza del Parco Nazionale della Val Grande quale esempio di best practice gestionale illustrando come da una visione integrata dei problemi si possa arrivare a proporre soluzioni basate su una solida conoscenza scientifica ma che riescono a conciliare diverse esigenze, quelle di conservazione delle risorse naturali e quelle di utilizzo del territorio anche a favore dell\u27uomo. Infine, si illustrer? una proposta progettuale (IdroLIFE), sottoposta alla attenzione della Unione Europea, e mirata alla tutela della biodiversit? acquatica nelle aree protette del VCO anche attraverso il ripristino e valorizzazione dei cosiddetti Corridoi Blu, i corridoi ecologici fluviali. Questa proposta progettuale ? condivisa oltre che da numerosi Enti Pubblici anche da stakeholders e cofinanziatori privati, nonch? associazioni piscatorie e ambientaliste, dimostrando che ? possibile raccogliere e conciliare sul tema della tutela e della conservazione degli ambienti acquatici, interessi, esperienze ed esigenze diversi
Il valore aggiunto della limnologia comparata: un confronto tra laghi delle Terre Alte per lo studio dei cambiamenti climatici
No full textNot availableAssodato che il cambiamento climatico ? in corso, molte sono ancora le incertezze sulla conseguente risposta da parte degli ecosistemi, in particolare di quelli acquatici. Come emerso sia dall\u27analisi delle serie storiche di dati, sia da indagini paleolimnologiche, questi ambienti, a differenza di quelli terrestri, presentano dei meccanismi di riposta pi? complessi, spesso non lineari, o non riconducibili ad una semplice relazione causa-effetto. Sono qui discussi esempi o casi di studio che evidenziano come le comunit? biologiche che vivono in ambienti acquatici abbiamo strutture peculiari e come queste caratteristiche siano rispondano agli impatti climatici. Per valutare in modo appropriato quale sar? l\u27evoluzione di questi ecosistemi nel prossimo futuro ? necessario aumentare la conoscenza di questi ambienti su scala sia spaziale sia temporale, in modo da poter discriminare il contributo di fattori locali o globali, antropici o naturali. In questo contesto gli ambienti acquatici delle Terra Alte possono dare un contributo significativo alla comprensione degli impatti del clima sugli ecosistemi acquatici
Learn PAd Simulation Environment: Refined Architecture and Prototype Implementation
No full textD6.2 is the second deliverable of Learn PAd Work-Package 6, focusing on the Business Process Simulation environment. The document specifies the refined architecture of the Business Process Simulation Engine and the monitoring environment of the Learn PAd Platform on the one hand, and provides a first implementation of its initial prototype on the other. In particular, the current document describes gamification techniques that complement the logical architecture of the simulator (presented in D6.1) in order to provide an entertaining and engaging session with a learner in a simulated work context. To this end, we identify the main gamification mechanisms of the simulation and monitoring environment, their functionalities and their interactions. In the prototype part of this deliverable we briefly describe the delivered code. We start by detailing (1) how to work (get the sources, build and run the platform) with the Learn PAd Simulation and then (2) how to use it
Introducing Open Dialogue in Italy: the role of participatory evaluation
No full textA pilot project started in Italy this year to implement and adapt the Open Dialogue (OD) approach in the context of seven different public mental health services (MHD). The project -financed by the Italian Health Ministry- includes a multi-stakeholder evaluation research and will consists of four distinct phases: a) preliminary assessment: conceptions of crisis and organizational issues; b) Open Dialogue training for the professionals; c) experimentation of OD and process evaluation; d) outcomes evaluation, comparing two matched areas (test area vs control area). In the preliminary assessment, we will use the multi-stakeholder approach- involving representatives of professionals, users and family members - to explore the various definitions and conceptions of "crisis", the practices related to "crisis interventions" and how the voices of users and family members are taken into account. In order to assess organizational issues, we will analyse the point of view of the professionals - through an open-ended questionnaire - and the heads of the seven MHD involved in project -through a semi-structured interview. We will focus on similarities and differences of their conception of OD, critical issues related to the implementation process of OD in the context of local services. The findings of the preliminary assessment will be presented and discussed with representatives of professionals, users and family members and researchers in the context of an International Expert Round Table, which is scheduled for the 10th of July in Rome. We would like to share and discuss the results of the overall process in the present workshop