Indice per la valutazione della qualità ecologica dei bacini artificiali mediterranei (MedPTI) a partire dalla composizione del fitoplancton: documento presentato al Ministero dell’Ambiente e della tutela del territorio e del mare

Secondo la Direttiva 2000/60/CE (WFD, Water Framework Directive), la valutazione della qualità ecologica dei corpi idrici deve essere ottenuta con l’uso di indici numerici costruiti a partire dai parametri biologici, confrontando il valore assunto nel sito in esame con quello di un sito di riferimento, attraverso il calcolo di un quoziente di qualità ecologica (Ecological quality ratio, EQR). L’indice qui proposto è stato sottoposto alla procedura di intercalibrazione, per ottenere i valori dell’indice corrispondenti alle condizioni di riferimento e ai limiti tra le classi di qualità e quindi il rispettivo EQR

A Numerical index for evaluating phytoplankton response to changes in nutrient levels in deep Mediterranean reservoirs

This paper proposes a new ecological index based on phytoplankton (MedPTI) as suggested by the European Directive 2000/60/CE, Water Framework Directive (WFD). The index is a useful tool to verify the impacts of eutrophication in Mediterranean reservoirs belonging to different categories of the WFD. Multiple data sets were employed to develop the MedPTI index. The calibration data set included data collected from 30 Sardinian reservoirs in 1994. A list of 44 selected taxa was obtained and used for index calculation. A second dataset including 48 averaged annual values from 10 reservoirs was used. Results showed good correlation between MedPTI and concentration of total phosphorus, which was the limiting nutrient in these reservoirs. The trophic classifications determined using the index agreed with the results from the OECD probabilistic model on the same series of data. Finally, the index was included in an international exercise to compare the definition of reference conditions and quality class boundaries against indices used in other Mediterranean countries

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

Deferral of assessment of pulmonary embolism

We evaluated a simplified algorithm for safely postponing diagnostic imaging for pulmonary embolism (PE). At the index visit, patients were identified as being at high or low risk of PE; the former received full dosage low molecular weight heparin while the latter were left untreated until performance of diagnostic imaging (max 72 hours). During this period, no thromboembolic events occurred in low-risk patients (0/211, 0.% [upper 95% CI 0.9%]); only one event occurred in those at high-risk (1/125, 0.8% [upper 95% CI, 1.2]). Our study demonstrates that diagnostic imaging for PE can be safely deferred for up to 3 days

Consequences of eutrophication in the management of water resources in Mediterranean reservoirs: A case study of Lake Cedrino (Sardinia, Italy)

Abstract One of the primary detrimental effects of eutrophication is the tendency of nuisance cyanobacterial species to increase in number and biomass in freshwater ecosystems. The aim of this study was to investigate possible management actions to control eutrophication and assure water use of a eutrophic deep Mediterranean climate reservoir, dominated by cyanobacteria. With this goal, we defined the trophic state of Lake Cedrino (Sardinia, Italy) and studied its phytoplankton, paying particular attention to cyanobacteria, and to seasonal variation of phytoplankton in relation to seasonal variation of environmental variables. The water samples were collected monthly from September 2010 to August 2011 at differing depths from the surface of the water to the bottom at a station located in the deeper portion of the reservoir. Physical, chemical, nutrient, qualitative and quantitative analyses of phytoplankton were performed, and the trophic state was evaluated based on the Trophic State Index and the OECD model. Abundance of nutrients and phytoplankton (cell density, biomass and chlorophyll a ) indicated a eutrophic condition of the reservoir. In summer, phytoplankton species composition was dominated by nuisance cyanobacteria, particularly Aphanizomenon flosaquae , thereby requiring management plans for harmful blooms. On the base of lake features, we propose management actions at different scales and levels to resolve eutrophication and to allow water use: from nutrient load reduction in the watershed (primarily from point-sources) to deep water aeration, to immediately face an attenuation of eutrophic effects. This study is the first explorative step in planning restoration of Lake Cedrino

Contrasting intra-annual patterns of six biotic groups with different dispersal mode and ability in Mediterranean temporary ponds

The temporal patterns of six biotic groups (amphibians, macroinvertebrates with active and passive dispersal mode, microcrustaceans, vascular plants and phytoplankton) and the responses of each biotic group to environmental variation (water, pond and landscape variables) were studied in a set of Sardinian temporary ponds

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

Long-term ecological studies on phytoplankton in Mediterranean reservoirs: a case study from Sardinia (Italy)

Artificial lakes are strategic water resources in the Mediterranean region but are one of the most vulnerable areas to the impacts of climate change, particularly to the expected significant decrease in water resources; therefore, enhancing the ability of water management to improve water quality is crucial. This study contributes to the knowledge of the long-term ecological features of Mediterranean artificial lakes based on a case study of Bidighinzu Lake in Sardinia, Italy, a warm, monomitic and hypereutrophic reservoir mainly used for drinking water. Among the different restoration actions carried out in Bidighinzu Lake to improve water quality is the reduction of nutrient loads from the watershed. To study multiannual trends of the trophic state, a long-term series (1988–2012) of both environmental variables and phytoplankton was analysed. Mann-Kendall tests revealed increasing trends for total nitrogen to total phosphorus ratios (TN:TP; significant in spring, summer, and winter) and decreasing trends for ammonium (winter and autumn), TP (all seasons), orthophosphate (spring, summer, and winter), reactive silica (autumn), and pH (summer). Among phytoplankton, significant increasing trends were assessed in biomass of Bacillariophyceae, Chlorophyceae, Dinophyceae, and Chrysophyceae. Cyanobacteria did not show a clear trend, although at the order level, Chroococcales significantly increased in summer and decreased in winter. Despite these major tendencies, the lake did not show significant improvement in its eutrophic state, probably due to an inherent resistance and the insufficient and/or not well calibrated or applied recovery actions

Long-term ecological studies on phytoplankton in Mediterranean reservoirs: a case study from Sardinia (Italy)

Artificial lakes are strategic water resources in the Mediterranean region but are one of the most vulnerable areas to the impacts of climate change, particularly to the expected significant decrease in water resources; therefore, enhancing the ability of water management to improve water quality is crucial. This study contributes to the knowledge of the long-term ecological features of Mediterranean artificial lakes based on a case study of Bidighinzu Lake in Sardinia, Italy, a warm, monomitic and hypereutrophic reservoir mainly used for drinking water. Among the different restoration actions carried out in Bidighinzu Lake to improve water quality is the reduction of nutrient loads from the watershed. To study multiannual trends of the trophic state, a long-term series (1988–2012) of both environmental variables and phytoplankton was analysed. Mann-Kendall tests revealed increasing trends for total nitrogen to total phosphorus ratios (TN:TP; significant in spring, summer, and winter) and decreasing trends for ammonium (winter and autumn), TP (all seasons), orthophosphate (spring, summer, and winter), reactive silica (autumn), and pH (summer). Among phytoplankton, significant increasing trends were assessed in biomass of Bacillariophyceae, Chlorophyceae, Dinophyceae, and Chrysophyceae. Cyanobacteria did not show a clear trend, although at the order level, Chroococcales significantly increased in summer and decreased in winter. Despite these major tendencies, the lake did not show significant improvement in its eutrophic state, probably due to an inherent resistance and the insufficient and/or not well calibrated or applied recovery actions

Lack of association between genetic variants in the mannose-binding lectin 2 (MBL2) gene and HPV infection

Genetic variants in the immunomodulatory gene mannose-binding lectin 2 (MBL2), were associated with risk, severity, and frequency of viral infections. In a case-control setting, we investigated the association of MBL2 functional polymorphisms with Human Papillomas Virus (HPV) infection. No differences between cases (HPV+) and controls (HPV-) were found in the distribution of each single genotypes or allele. Haplotype analysis did not show any difference between HPV+ and HPV- groups