Multipoint passive monitoring in packet networks

Traffic monitoring is essential to manage large networks and validate Service Level Agreements. Passive monitoring is particularly valuable to promptly identify transient fault episodes and react in a timely manner. This paper proposes a novel, non-invasive and flexible method to passively monitor large backbone networks. By using only packet counters, commonly available on existing hardware, we can accurately measure packet losses, in different segments of the network, affecting only specific flows. We can monitor not only end-to-end flows, but any generic flow with packets following several different paths in the network (multipoint flows). We also sketch a possible extension of the method to measure average one-way delay for multipoint flows, provided that the measurement points are synchronized. Through various experiments we show that the method is effective and enables easy zooming in on the cause packet losses. Moreover, the method can scale to very large networks with a very low overhead on the data plane and the management plane

Inhibition of Larval Development of Marine Copepods Acartia tonsa by Neonocotinoids

Neonicotinoids (NEOs) are neurotoxic pesticides widely used in agriculture due to their high effectiveness against pest insects. Despite their widespread use, very little is known about their toxicity towards marine organisms, including sensitive and ecologically relevant taxa such as copepods. Thus, we investigated the toxicity of five widely used NEOs, including acetamiprid (ACE), clothianidin (CLO), imidacloprid (IMI), thiacloprid (THI), and thiamethoxam (TMX), to assess their ability to inhibit the larval development of the copepod Acartia tonsa. The more toxic NEOs were ACE (EC50 = 0.73 μg L−1), TMX (EC50 = 1.71 μg L−1) and CLO (EC50 = 1.90 μg L−1), while the less toxic compound was IMI (EC50 = 8.84 μg L−1). Early life-stage mortality was unaffected by NEOs at all of the tested concentrations. The calculated toxicity data indicated that significant effects due to ACE (EC20 = 0.12 μg L−1), THI (EC20 = 0.88 μg L−1) and TMX (EC20 = 0.18 μg L−1) are observed at concentrations lower than established chronic aquatic life benchmarks reported by USEPA for freshwater invertebrates. Nevertheless, since environmental concentrations of NEOs are generally lower than the threshold concentrations we calculated for A. tonsa, the effects may be currently of concern only in estuaries receiving wastewater discharges or experiencing intense runoff from agricultur

WFD and eutrophication assessment: the role of nitrogen as a driving nutrient in shaping phytoplankton assemblages in 13 Italian water bodies

This research was carried out in the frame of the LIFE project INHABIT (Local hydro-morphology, habitat and RBMPs: new measures to improve ecological quality in South European rivers and lakes). A key action of the project was finalized to detect the relationship between nutrients on the ecological quality of water bodies and to identify management options to reduce their effects on aquatic ecosystems to be included in RBMPs, focusing, in particular, on nitrogen. The outcome of the project will serve as a basis for the implementation of Water Framework Directive river basis management plans in Italy and, possibly, in Europe. Analyses were carried out on data from 13 lakes, located in two Italian Regions, Piedmont (North-western Italy, 7 lakes; 5 natural and 2 reservoirs) and Sardinia Island (6 lakes; 1 natural, 5 reservoirs). Seasonal samples were collected in each lake, from 3 to 6, depending on environmental characteristics. The following variables were considered: water temperature, conductivity, alkalinity, pH, dissolved oxygen, SRP, TP, N-NH4, N-NO3, TN, RSi, Secchi depth and chlorophyll. Species/environment relationships were explored using multivariate statistical techniques (CCA, RDA and Generalised Additive Models). Analysis was carried out on 23 phytoplankton orders and 51 genera/species. The results pointed out an increase of cyanobacteria (Nostocales and Oscillatoriales) with the increasing nitrogen availability. Moreover, a positive response of some chlorophytes species was also observed. On the other side, diatoms declined when nitrogen concentration increased. Our findings, confirming some experimental results previously obtained, emphasize the need for a further attention towards the impact of increasing nitrogen, in particular from atmospheric inputs, when restoration plans against eutrophication are designed

Interaction with the Phosphotyrosine Binding Domain/Phosphotyrosine Interacting Domain of SHC Is Required for the Transforming Activity of the FLT4/VEGFR3 Receptor Tyrosine Kinase

The FLT4 gene encodes two isoforms of a tyrosine kinase receptor, which belongs to the family of receptors for vascular endothelial growth factor. As the result of an alternative processing of primary mRNA transcripts, the long isoform differs from the short isoform by an additional stretch of 65 amino acid residues located at the C terminus and containing three tyrosine residues, Tyr1333, Tyr1337, and Tyr1363. Only the long isoform is endowed with a transforming capacity in fibroblasts. We show that this activity is related to the capacity of the tyrosine 1337-containing sequence to interact with the phosphotyrosine binding domain of the SHC protein. This demonstrates that a functional property of this newly described domain includes relay of mitogenic signals. In addition, it shows that the same receptor can mediate different functions through the optional binding of the phosphotyrosine binding domain and that the alternative use of this domain is sufficient to direct the signal toward different pathways

The frail patient undergoing cardiac surgery: lessons learned and future perspectives

Frailty is a geriatric condition characterized by the reduction of the individual's homeostatic reserves. It determines an increased vulnerability to endogenous and exogenous stressors and can lead to poor outcomes. It is an emerging concept in perioperative medicine, since an increasing number of patients undergoing surgical interventions are older and the traditional models of care seem to be inadequate to satisfy these patients' emerging clinical needs. Nowadays, the progressive technical and clinical improvements allow to offer cardiac operations to an older, sicker and frail population. For these reasons, a multidisciplinary team involving cardiac surgeons, clinical cardiologists, anesthesiologists, and geriatricians, is often needed to assess, select and provide tailored care to these high-risk frail patients to optimize clinical outcomes. There is unanimous agreement that frailty assessment may capture the individual's biological decline and the heterogeneity in risk profile for poor health-related outcomes among people of the same age. However, since commonly used preoperative scores for cardiac surgery fail to capture frailty, a specific preoperative assessment with dedicated tools is warranted to correctly recognize, measure and quantify frailty in these patients. On the contrary, pre-operative and post-operative interventions can reduce the risk of complications and support patient recovery promoting surgical resilience. Minimally invasive cardiac procedures aim to reduce surgical trauma and may be associated with better clinical outcome in this specific sub-group of high-risk patients. Among postoperative adverse events, the occurrence of delirium represents a risk factor for several unfavorable outcomes including mortality and subsequent cognitive decline. Its presence should be carefully recognized, triggering an adequate, evidence based, treatment. There is evidence, from several cross-section and longitudinal studies, that frailty and delirium may frequently overlap, with frailty serving both as a predisposing factor and as an outcome of delirium and delirium being a marker of a latent condition of frailty. In conclusion, frail patients are at increased risk to experience poor outcome after cardiac surgery. A multidisciplinary approach aimed to recognize more vulnerable individuals, optimize pre-operative conditions, reduce surgical invasivity and improve post-operative recovery is required to obtain optimal long-term outcome

The EcoThermo project: key and innovative aspects

In this paper we present the most innovative aspects of the EC-FP7 EcoThermo project. The main aim of the project consists on innovating the technique of heat cost allocation in buildings with a centralized heating system, overcoming the heat cost allocator drawbacks for reliability, measurement reproducibility and traceability and contexts of applications. Given the complexity of the project, we will focus on its main aspects, such as the use of a virtual sensor to estimate the radiators heating power, the design of electronic valves fitted out with an energy harvesting system and the original wireless communication protocol

Aree di studio, siti e strategie di campionamento, difficolt? complessive e sintesi dei principali risultati. Parte B: Laghi

After the preliminary actions for the selection of sites, a successive step was reached: the definition of the lakes under investigation within the project INHABIT. In this deliverable we report a brief description of each morphological and morphometric, geological and geomorphological features, with the description of the origin of the lakes, of land use, particularly important to understand and define the insistent pressure of the lake and imposed from the basin, of hydrology, an integral part of the characteristics and the ecological quality of a lake, and of the pressures due to sewage, industry, agriculture and livestock. In some lakes, we also reported the current trophic status and its evolution over time and the actions planned to improve water quality on the basis of the European Directive 2000/60/EC, the Water Framework Directive (WFD). Furthermore, for all studied lakes we also reported the regional maps for showing the watershed and its hydrography, and an aerial photo to help to identify the morphological characteristics of the lake cuvette. On each lake under study, the project involves the collection of biological samples for the four parameters of quality, as indicated by the WFD, and hydro-morphological characteristics, according to the sampling protocols defined at the national level and presently subject of international harmonization. Chapter 1 provides a description of sampling methods and procedures for the four biological parameters investigated: macroinvertebrates, phytoplankton, macrophytes and fish. Each sampling protocol identifies the sampling period, different for each parameter. For example, for the macrobenthos were identified two annual periods (one spring and one fall), for macrophytes the sampling period is during the maximum vegetative growth of plants. Phytoplankton, on the contrary, is sampled periodically several times during the year and, finally, fishes are sampled from spring to autumn. In the description of the protocols and procedures, sampling sites are also identified. The point of investigation vary from element to element. For example, macrophytes and macrobenthos are sampled along transects, i.e. "lines" distributed in a different way to cover the entire lake. On the contrary, phytoplankton is sampled at the deepest point of the lake, and fishes are collected in different areas arranged in different areas of the lake. In this chapter are also included photos of the equipment used for sampling, and of the sampling procedure when relevant. During the collection of macroinvertebrates and phytoplankton samples, water samples for chemical analysis are also collected. Chemical data are used to support and complete the description and the ecological characterization of the lakes. Furthermore, during macroinvertebrates samples, we also collected sediment samples for particle size and chemical analysis, to define the correct placement of transects on the basis of sediment characteristics and to collect basic information needed for the interpretation of data. In addition to the biological parameters, hydro-morphological characteristics of the studied lakes were also investigated, using the Lake Habitat Survey (LHS), a method developed for the English lakes and the being presently standardized at the European level. In this project, LHS will be validated for the Italian lakes. The lakes selected for investigation are 12, including natural and heavily modified waterbodies, and located in two regions: Piedmont and Sardinia. Seven sites are in Piedmont and 5 in Sardinia. The project originally planned 6 sites for each region, including the only natural lake in Sardinia: Lake Baratz. During the first sampling campaign in Sardinia, when macrobenthos was collected, he became aware of the presence of unexploded ordnance on the lake bottom. Working on, and in proximity of the bottom of the lake was excessively dangerous, and it was decided to transfer the activities on the four biological parameters in another lake, Lake Piccolo di Avigliana, a natural lake in Piedmont, lying in a natural park and of particular ecological interest . However, it was decided to keep the sampling of Lake Baratz for the biological parameters which can be sampled without danger, i.e. phytoplankton and macrophytes. In effect, being this lake the only natural lake in Sardinia, it can provide information on natural lakewater communities in the Region, otherwise missing. Selected lakes in Piedmont are the following: Lake Piccolo di Avigliana, in a Regional Park, Lake Candia, in a Provincial Park, Lake Viverone, subject to strong touristic pressure, Lake Sirio, less impacted by tourism, and two heavily modified waterbodies: Morasco, in the basin of River Toce and Serr? in the Gran Paradiso National Park, both built for hydroelectric purposes. In Sardinia, all the 5 fully investigated lakes are heavily modified waterbodies, namely Bidighinzu, Sos Canales, Liscia, Posada and Torrei. The main use for most of these basins is providing drinking water, only for Posada is providing water for agriculture. However, waters from Liscia and Posada are also used for other purposes, irrigation for the former and industry, drinking water and hydroelectric power for the latter. During the sampling campaigns, and particularly during the application of the LHS method which requires to examine the transition between an observation point and the following along the entire lake shore, we made a number of pictures of each lake in order to document the pressures on the coast, such as beaches, docks, artworks, human activities, and to show peculiar coastal and subcoastal habitats, such as sandy areas, reed beds, rocky areas, oxbow lakes, wetlands, riparian vegetation and macrophytes. A small selection of this vast collection of pictures is used in chapters 3 and 4, to show the features of each sampled lake. Sampling activities are not yet finished for all quality parameters, both because of the late selection Lake Piccolo di Avigliana, and because of difficulties due to weather conditions. It is expected to complete all sampling and analyses by Summer 2012. Preliminary data can be found in Chapter 5 for both regions, but only for some parameters and some lakes. In effect, biological analyses require different time and commitment for the different biological elements quality, so that the results the could be obtained faster are reported in this deliverable. A further activity in preparation for the near future is the preparation of a database for the hydromorphological parameters to be used for the calibration and the development of synthetic indices of morphological alteration and habitat quality. This adjustment is necessary because, in an earlier phase of verification of the applicability of the LHS method to the hydromorphological characteristics of the Italian lakes, it emerged the necessity to change some entries in the field card. These changes must also be included in the database associated with the method and in the formulation of the index.Dopo le azioni preliminari per la scelta dei siti si ? giunti, a passi successivi, alla definizione dei laghi oggetto di indagine all\u27interno del progetto INHABIT. In questo deliverable si riporta una sintetica descrizione delle caratteristiche morfologiche e morfometriche di ciascuno, le caratteristiche geologiche e geomorfologiche, con la descrizione della formazione di alcuni laghi, l\u27uso del suolo, particolarmente importante per capire e definire le pressioni insistenti sul lago e gravanti dal bacino, l\u27idrologia, parte integrante delle caratteristiche e della qualit? ecologica di un lago, le pressioni puntuali dovute a scarichi fognari e/o industriali, agricoli e zootecnici. Di alcuni laghi, si ? anche riportato lo stato trofico attuale e la sua evoluzione nel tempo e le azioni regionali intraprese o che si intendono intraprendere per migliorarne la qualit? alla luce delle indicazione della WFD 2000/60. Inoltre, per tutti i laghi studiati si sono riportate anche la cartografia tecnica regionale per l\u27individuazione di ciascun bacino imbrifero e della rete idrografica principale che lo caratterizza, e una foto aerea per meglio identificare le caratteristiche morfologiche della cuvetta lacustre. Su ciascun lago oggetto di studio, il progetto prevede la raccolta di campioni per i quattro parametri biologici di qualit?, cos? come indicati dalla Direttiva Quadro sulle Acque, e delle caratteristiche idromorfologiche, secondo i protocolli di campionamento definiti a livello nazionale e oggetto di intercalibrazione a livello internazionale. Nel capitolo 1 sono riportate una descrizione delle metodiche e delle modalit? di campionamento per i quattro parametri biologici indagati, macroinvertebrati, fitoplancton, macrofite e pesci. Ogni protocollo di campionamento individua il periodo di campionamento, diverso per ciascun parametro, ad esempio per il macrobenthos si sono individuati due periodi annuali (uno primaverile e l\u27altro autunnale), per le macrofite il periodo di campionamento ? quello del massimo sviluppo vegetativo delle piante, mentre il fitoplancton viene raccolto periodicamente diverse volte, durante l\u27anno di campionamento. Infine i pesci sono campionati da primavera ad autunno. Nella descrizione del protocollo e delle modalit? di campionamento, vengono anche individuati i siti di lavoro, ovvero i punti di indagine, che variano molto da elemento a elemento. Ad esempio, le macrofite e il macrobenthos vengono campionati lungo un transetto, quindi su diverse "linee" distribuite in modo diverso fino a coprire tutto il lago. Il fitoplancton viene campionato nel punto pi? profondo del lago, quindi risulta un campionamento "puntuale" e i pesci vengono raccolti in diverse aree disposte in diverse zone del lago, si possono quindi pensare come campioni "areali". Nel suddetto capitolo si sono riportate anche foto della strumentazione necessaria e utilizzata per il campionamento e altre relative ad alcune fasi di raccolta dei campioni. Unitamente alla raccolta della fauna a macroinvertebrati e del fitoplancton vengono anche raccolti campioni di acqua per le analisi chimiche da utilizzare a sostegno e a completamento delle indagini e della caratterizzazione ecologica del lago. Inoltre, sempre unitamente al campionamento dei macroinvertebrati vengono prelevati campioni di sedimento per l\u27analisi granulometrica e chimica, per definire il corretto posizionamento dei transetti e raccogliere informazioni complementari ma basilari, per l\u27interpretazione dei dati. Oltre ai parametri biologici si sono indagate anche le caratteristiche idromorfologiche di ciascun lago scelto, utilizzando il metodo Lake Habitat Survey (LHS), nato per i laghi inglesi e oggetto di standardizzazione a livello europeo, e in questo progetto, oggetto di validazione per i laghi italiani. I laghi su cui effettuare campionamento e indagine sono 12, tra naturali e fortemente modificati, e situati nelle due regioni Piemonte e Sardegna, suddivisi in 7 laghi in Piemonte e 5 in Sardegna. Inizialmente erano previsti 6 laghi ciascuna regione con l\u27inclusione dell\u27unico lago naturale sardo: il Lago Baratz. Dopo la prima campagna di campionamento in Sardegna, quella relativa al macrobenthos, si ? venuti a conoscenza della presenza di ordigni inesplosi sul fondo del lago. Giudicando pericoloso lavorare sui suoi sedimenti ma anche nelle vicinanze del fondo stesso, si ? deciso di continuare l\u27attivit? sui quattro parametri biologici in un altro lago, il Lago Piccolo di Avigliana, lago naturale piemontese, zona di Parco Naturale e di particolare interesse ecologico. Si ? comunque deciso di mantenere il campionamento del Lago Baratz per quei parametri giudicati non pericolosi, fitoplancton e macrofite in quanto, essendo l\u27unico lago naturale sardo riveste una particolare importanza sia per la Regione Sardegna sia per la raccolta di informazioni biologiche nella Regione, altrimenti mancanti. I laghi scelti quindi sono, in Piemonte: il Piccolo di Avigliana, il Candia e il Viverone nell\u27anfiteatro morenico di Ivrea, il primo Parco Provinciale, il secondo meta turistica e oggetto quindi di forti pressioni sia sulle rive che sull\u27intero lago; il Sirio di particolare interesse sia turistico che naturalistico e due corpi idrici fortemente modificati: il Morasco, nel bacino dell\u27Alto Toce e il Serr? all\u27interno del Parco del Gran Paradiso, entrambi creati a scopo idroelettrico. Per quanto riguarda la Sardegna i 5 laghi indagati in modo completo sono tutti corpi idrici fortemente modificati e sono: il Bidighinzu, il Sos Canales, il Liscia, il Posada e il Torrei; l\u27utilizzo prevalente per questi bacini ? quello potabile tranne che per il Posada che ? irriguo. Le acque del Liscia e del Posada sono utilizzate anche per altri scopi, irriguo e industriale il primo, potabile e idroelettrico il secondo. Durante le campagne di campionamento e soprattutto, durante l\u27applicazione del metodo idromorfologico che prevede il passaggio tra un punto di osservazione e l\u27altro, lungo tutto il perimetro sotto costa, si sono effettuate numerose fotografie di ciascun lago, per documentare sia le pressioni sulla costa, come spiagge attrezzate, banchine, artificializzazioni di varia natura, attivit? presenti, che particolari habitat litorali e sub litorali, come zone sabbiose, canneti, zone rocciose, lanche, aree umide, nonch? vegetazione spondale e riparia e macrofite. Del vasto repertorio fotografico raccolto si sono riportate solo alcune delle principali caratteristiche rilevate e sopra descritte, inserite nei capitoli 3 e 4, relativi ai singoli laghi campionati, rispettivamente in Piemonte e in Sardegna. Il lavoro di campionamento non ? ancora finito per tutti i parametri di qualit?, sia a causa della scelta tardiva del Lago Piccolo di Avigliana, sia per difficolt? di varia natura dovute alle condizioni meteorologiche. Si prevede di concludere tali attivit? entro l\u27estate del 2012. Le prime elaborazioni disponibili sono riportate nel capitolo 5 per entrambe le regioni, ma solo per alcuni parametri e per alcuni laghi. La determinazione delle specie presenti non richiede lo stesso tempo e lo stesso impegno per tutti i parametri di qualit? di conseguenza la chiusura dell\u27identificazione dei campioni raccolti sar? effettuata nelle attivit? prossime future. Un\u27altra attivit? in previsione per il prossimo futuro ? quella della taratura del database per i parametri idromorfologici per l\u27elaborazione degli indici sintetici di alterazione morfologica e di qualit? degli habitat. Tale taratura risulta necessaria in quanto, in una precedente fase di verifica dell\u27applicabilit? del metodo LHS alle caratteristiche idromorfologiche dei laghi italiani, ? stato necessario variare qualche voce nella scheda di campo. Tali variazioni dovranno essere inserite anche nel database associato al metodo

Impacts of exhaust gas cleaning systems (EGCS) discharge waters on planktonic biological indicators

Exhaust Gas Cleaning Systems (EGCS), operating in open-loop mode, continuously release acidic effluents (scrubber waters) to marine waters. Furthermore, scrubber waters contain high concentrations of metals, polycyclic aromatic hydrocarbons (PAHs), and alkylated PAHs, potentially affecting the plankton in the receiving waters. Toxicity tests evidenced significant impairments in planktonic indicators after acute, early-life stage, and long-term exposures to scrubber water produced by a vessel operating with high sulphur fuel. Acute effects on bacterial bioluminescence (Aliivibrio fischeri), algal growth (Phaeodactylum tricornutum, Dunaliella tertiolecta), and copepod survival (Acartia tonsa) were evident at 10 % and 20 % scrubber water, while larval development in mussels (Mytilus galloprovincialis) showed a 50 % reduction at ∼5 % scrubber water. Conversely, larval development and reproductive success of A. tonsa were severely affected at scrubber water concentrations ≤1.1 %, indicating the risk of severe impacts on copepod populations which in turn may result in impairment of the whole food web

Variabilit? naturale e legata a fattori antropici nei siti lacustri studiati

The natural variability of the biotic components, in particular of those showing seasonal cycles, often leads to significant changes of biomass as well as specific composition. This means that the choice of sampling frequency and distribution during the year may be crucial when assessing the ecological quality of a waterbody, starting from the structure of biotic communities. Among the four biological quality elements used to classify the lakes, three of them (phytoplankton, macrophytes and macroinvertebrates) show a marked seasonality and/or a certain degree of spatial variability. This document has the aim to evaluate how the metrics used are sensitive to the natural variability, especially respect to their response to the pressure gradients. The analysis was carried out on data collected during the project and is limited to phytoplankton and macrophytes, because the examination of autumn samples of macroinvertebrates, is still in progress. Regarding phytoplankton, three metrics defined by Italian national legislation (composition indices, chlorophyll and biovolume) were analyzed, comparing the variability due to anthropogenic origin (expressed by the gradient of total phosphorus) with the natural one (seasonal variations on different time scales) and estimating the uncertainty in the classification using different sampling frequencies. In the case of macrophytes, monitoring methods and classification were analyzed respect to their accuracy in assessing if the variability between sites, explained by a different anthropogenic pressure, is actually greater than the variance within the individual lake. In addition, we want to determine if the sampling effort, as established by the monitoring protocols, is adequate to the needs of the classification. Our analysis showed that the variability of phytoplankton metrics reflects the trophic gradient and is more significant than that explained by seasonal fluctuations, demonstrating the robustness of the indicators used. Moreover, the phytoplankton assemblages reveal a high stability in interannual patterns of succession. Conversely, the general formulation of the macrophytic index may need to be redefined to better understand the differences in ecological quality between lakes. Furthermore, as concerns macrophytes, a significant reduction of the sampling effort does not seem to be possible without compromising the quality of classification, while, as regards phytoplankton, it would be acceptable to reduce the number of annual samples from 6 to 4 without compromising the result of the classification, while observing the seasonality, because our analysis suggests that phytoplankton samples concentrated in a single season lead to increased uncertainty in the classification.La variabilit? naturale delle componenti biotiche, in modo particolare di quelle che mostrano cicli su base stagionale, porta a cambiamenti spesso significativi della composizione specifica e della biomassa. Questo significa che la scelta della frequenza di campionamento e la distribuzione dei prelievi nel corso dell\u27anno possono rappresentare dei fattori critici quando si tratta di valutare la qualit? ecologica a partire dalla struttura delle comunit? biotiche. Delle quattro componenti biologiche usate per classificare i laghi, tre (fitoplancton, macrofite e macroinvertebrati) mostrano una spiccata stagionalit? e/o una certa variabilit? spaziale. Il presente documento ? stato redatto con lo scopo di valutare quanto le metriche utilizzate siano sensibili alla variabilit? di origine naturale, soprattutto in relazione alla loro risposta rispetto ai gradienti di pressione. L?analisi ? stata condotta sui dati raccolti nel corso del progetto ed ? limitata al fitoplancton ed alle macrofite, poich? l?esame dei campioni autunnali dei macroinvertebrati ? tuttora in corso. Per quanto riguarda il fitoplancton sono state analizzate tre metriche indicate dalla normativa nazionale (indici di composizione, clorofilla e biovolume), confrontandone la variabilit? di origine antropica (espressa dal gradiente di fosforo totale) con quella naturale (stagionalit? su diverse scale temporali) e stimando l?incertezza nella classificazione con frequenze di prelievo diverse. Nel caso delle macrofite, i metodi di monitoraggio e di classificazione sono stati analizzati rispetto alla loro accuratezza nel valutare se la variabilit? tra ambienti, dovuta alla diversa pressione antropica, sia effettivamente maggiore rispetto alla varianza all?interno del singolo lago. Inoltre, si vuole valutare se lo sforzo di campionamento, previsto dai protocolli di monitoraggio, sia adeguato alle esigenze della classificazione. La nostra analisi ha messo in evidenza che la variabilit? delle metriche fitoplanctoniche rispecchia il gradiente trofico ed ? pi? significativa rispetto a quella spiegata dalle fluttuazioni stagionali, dimostrando la robustezza degli indicatori utilizzati e che le associazioni fitoplanctoniche rilevano un grande stabilit? negli schemi di successione interannuali. Viceversa, la formulazione generale dell?indice macrofitico potrebbe necessitare di una ridefinizione per meglio cogliere le differenze di qualit? ecologica tra i laghi. Inoltre, nel caso delle macrofite, una riduzione significativa dello sforzo di campionamento non pare possibile senza compromettere la qualit? della classificazione, mentre, per quanto riguarda il fitoplancton, sarebbe accettabile ridurre il numero dei prelievi annuali da 6 a 4 senza compromettere il risultato della classificazione, rispettando comunque la stagionalit?, poich? prelievi di fitoplancton concentrati in una sola stagione determinano una maggiore incertezza nella classificazione

Indici per la valutazione della qualit? ecologica dei laghi

Methods are presented to evaluate the biological quality of Italian lakes based on phytoplankton, macrophytes, fishes, benthic fauna and hydromorphology