148 research outputs found

    Protocollo di campionamento della fauna ittica dei laghi italiani

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    No abstract availableIl documento seguente si prefigge di fornire la metodologia di campionamento per il monitoraggio della fauna ittica nei laghi italiani. Le metodologie di campionamento descritte nel seguente protocollo permettono, attraverso un sistema armonizzato, di ottenere i dati necessari a stimare la frequenza delle specie ittiche in un ambiente lacustre, l?abbondanza e la biomassa relativa, la struttura dei singoli popolamenti

    Indice per l\u27analisi dello stato di qualit? della fauna ittica finalizzato alla valutazione dello stato ecologico dei laghi italiani: Lake Fish Index (LFI)

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    No abstract availableIndici per la valutazione della qualit? ecologica dei laghi. Indice per l\u27analisi dello stato di qualit? della fauna ittica finalizzato alla valutazione dello stato ecologico dei laghi italiani: Lake Fish Index (LFI

    Lo stato della fauna ittica del Lago di Caldaro (BZ)

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    No abstract availableLa presente relazione si propone di analizzare lo stato della fauna ittica del Lago di Caldaro (BZ), attraverso le informazione acquisite con un campionamento intensivo effettuato nel corso del mese di settembre 2010 e attraverso le informazioni fornite dall?Ufficio Pesca della Ripartizione Foreste della Provincia autonoma di Bolzano. I risultati sono commentati anche alla luce del quadro limnologico generale del corpo idrico quale risulta dalle indagini del Laboratorio Biologico di APPA Bolzano e nonch? delle recenti normative relative alla qualit? ed allo stato ecologico dei corpi idrici superficiali (EU 2000, D.M. 56/2009). Nel corso della trattazione saranno affrontati brevemente i seguenti argomenti: ? La metodologia di campionamento ? La composizione e la struttura della comunit? ittica del Lago di Caldaro ? La struttura di popolazione delle principali specie ittiche ? Struttura di taglia ed et? delle principali specie ittiche ? Definizione dei parametri biologici delle specie catturate utili allo sfruttamento sostenibile degli stock ? Analisi dello stato di qualit? della fauna ittica mediante l?indice sintetico Lake Fish Index (LFI) ai fini della classificazione dello stato ecologico del Lago di Caldaro ? Discussione dei risultati e considerazioni di carattere gestionale alla luce del quadro limnologico complessivo

    The recent invasion of Rutilus rutilus (L.) (Pisces: Cyprinidae) in a large South-Alpine lake: Lago Maggiore

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    Very recently, a common cyprinid fish species at northern latitude, the roach (Rutilus rutilus L.) has been observed in the large south-alpine Lago Maggiore for the first time. The colonization of the lake has the characteristics of an invasion. In order to investigate this new fish population, benthic multi-mesh and commercial gill nets were used to sample fish in a wide gulf in the central part of the lake (Golfo Borromeo) from February to October 2006. In total 779 roach (TL: 5.5 - 38.8 cm) were caught, aged, sexed and stomach analyzed. Fecundity was assessed by counting the eggs in ripe gonads of females of age 3 and 4. The roach have become clearly the dominant species in the catches, constituting over 70% of the biomass and 70% of the numbers caught. None of the roach exceeded 8 years in age. They grow very fast (?\u27=2.55) and have high fecundity (Fabs=13740?4700 S.D. at age 3 and Fabs=14768?5642 S.D. at age 4). The diet spectrum is wide and characterized by a strong seasonality. In early spring algae (benthic and planktonic algae), benthos and detritus prevail, whereas in summer zooplankton is the most frequent food item. In autumn roach switch back to benthos and detritus. Algae occur more frequently in young specimens while zooplankton, benthos and detritus in adults. The roach population is practically unimpacted by fishing. The minimum legal mesh size (25 mm) of gillnets, used by commercial fishermen, selects roach at the mean LT of 21.2 cm, which is over its length at maturity. The results suggest that roach established a viable population in Lago Maggiore less than a decade ago and rapidly became one of the dominant (if not the dominant) fish species. The possible consequence for the fish fauna in general and for the ecological status of the whole lake is briefly discussed

    In memory of Ettore Grimaldi

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    Ettore Grimaldi (1934-2015) was one of the brightest and active ichthyologists in Italy. He was a man of great enthusiasm, boundless energy and great curiosity. He was a person with an open mind. He originally visited the Institute of Pallanza in June 1957 as a master student at the Faculty of Veterinary Medicine, University of Milan. He was formally called back by the Director Vittorio Tonolli, as a research assistant in 1962..

    Plastic sources: A survey across scientific and grey literature for their inventory and relative contribution to microplastics pollution in natural environments, with an emphasis on surface water

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    Embargo until 22 July 2019Plastic debris are at present recognized as an emerging potential threat for natural environments, wildlife and humans. In the past years an increasing attention has been addressed to investigate the presence and concentration of plastic debris in the ecosystems, including surface waters. Scientific literature extensively describes the ingestion by aquatic fauna, the transfer into food webs and the potential action as a vector for toxic compounds or alien microorganisms. Although the scientific community addresses this issue with considerable effort, many questions remain open. In particular, new sources of microplastics have been recently recognized, possibly representing major environmental inputs compared to those previously considered. In addition to the already renowned sources such as the embrittlement of plastic litter and microbeads released from personal care products, microplastic can be released also by washing of synthetic clothes, abrasion of vehicles tyres and from the weathering of different kind of paints. This review tries to exhaustively enumerate all the possible sources of plastic litter that have been identified so far and to report quantitative assessments of their inputs on microplastics pollution to natural environments reported in scientific and grey literature, with an emphasis on surface waters.acceptedVersio

    Aggiornamento delle conoscenze relative alla fauna ittica del Lago di Mergozzo (VB) con brevi note gestionali

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    No abstract availableLa presente relazione si propone di analizzare sinteticamente lo stato della fauna ittica del Lago di Mergozzo (VB), ed evidenziarne le peculiarit? e criticit? confrontando i dati attuali con quelli relativi ad indagini dettagliate effettuate in passato (Giussani 1994). Il campionamento dell\u27ittiofauna del Lago di Mergozzo rientra nelle attivit? incluse in due progetti di ricerca e gestione delle risorse idriche finanziati dalla Comunit? Europea: il progetto WISER (www.wiser.eu) e il progetto LIFE + Inhabit (www.life-inhabit.it), entrambi focalizzati alla implementazione della Direttiva Europea sulle Acque (2000/60/CE). Tali progetti, finalizzati all\u27utilizzo di indicatori biologici per valutare lo stato ecologico degli ecosistemi acquatici, vedono l\u27impegno comune di realt? come ARPA Piemonte e numerosi e qualificati Istituti di Ricerca Italiani ed Esteri, tra cui il CNR-ISE. Al di l? dell\u27impegno istituzionale legato a progetti di ricerca su larga scala, il CNR-ISE si propone di redigere la presente relazione anche con lo scopo di fornire agli attori locali (Comune di Mergozzo, Associazione Pescatori del Lago di Mergozzo e, in secondo luogo, Provincia del VCO) informazioni utili alla conoscenza e gestione dell\u27ittiofauna di questo lago

    Contaminanti nelle acque lacustri

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    No abstract availableConfronto von i dati pregressi e analisi temporali della contaminazion

    Past, present and future of the fish community of Lake Orta (Italy), one of the world\u27s largest acidified lakes

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    Since 1926, the fishes in Lake Orta, one of Italy\u27s deepest natural lakes, were heavily damaged by profundal hypoxia and acidification linked to oxidation of ammonia from industrial effluents and by industrial metal pollution. Of the original 28 fish species, only perch survived the lake\u27s contamination. Recently, the water quality of the lake has been largely restored by reductions in pollutant inputs, and a massive liming intervention. These interventions restored fish habitat, but it is unclear whether the recent fish reintroductions were successful, and the present status of the fish community is unknown. Here we reviewed the history of the Lake Orta fish assemblage. Using an extensive 2014 sampling campaign, we compared the present fish community to both its pre-pollution composition and to the assemblages of nearby un-polluted, but otherwise similar lakes, Lake Mergozzo and Lake Maggiore. While nearshore fish density now appears normal in lake Orta, the open water community remains impoverished both in numbers and in species. Epilimnetic and hypolimnetic benthic nets were dominated by perch and roach in all the three lakes, but the catch of pelagic nets differed among lakes. Perch (Perca fluviatilis), rudd (Scardinius erythrophthalmus) and brown trout (Salmo trutta) dominated in Lake Orta while shad (Alosa fallax lacustris) and coregonids (Coregonus spp.) were dominant in the open waters of the other two lakes, but missing from Lake Orta. Many fully or partially migratory species, including marble trout (Salmo trutta marmoratus), eel (Anguilla Anguilla) and barbel (Barbus plebejus) were also missing from Lake Orta, a consequence of their initial extirpation and blocked re-colonization routes along the River Strona. In comparison with both pre-pollution and contemporary reference data, the fish community of Lake Orta has not been rehabilitated. The recovery of the littoral community is complete, but cold water species such as burbot (Lota lota), Arctic charr (Salvelinus alpinus) and bullhead (Cottus gobio) are still lacking, as are the pelagic zooplanktivores European whitefish (Coregonus lavaretus) and shad, which dominate offshore communities in the reference lakes, as they did a century ago in Lake Orta. To propose priorities for fish community rehabilitation in Lake Orta, we categorized the conservation, ecological and fishing values of each missing fish species in the lake, and evaluated the cost and probability of success of the needed intervention for each species. This analysis indicated that rehabilitation of shad and European whitefish should receive highest priority

    Caratterizzazione tassonomica e funzionale della comunit? ittica nel Lago Maggiore con particolare riferimento alle specie alloctone invasive di recente comparsa e alla sovrapposizione della nicchia trofica

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    Not availableRicerche sull\u27evoluzione del Lago Maggiore. Aspetti limnologici. Programma triennale 2013-2015. Campagna 2013. Caratterizzazione tassonomica e funzionale della comunit? ittica nel Lago Maggiore con particolare riferimento alle specie alloctone invasive di recente comparsa e alla sovrapposizione della nicchia trofica. Premessa. Composizione della comunit? ittica del Lago Maggiore: abbondanze assolute e relative; distribuzione verticale; caratterizzazione della comunit? ittica: considerazione conclusive. Sovrapposizione nella nicchia trofica
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