1,721,001 research outputs found
Zooplankton composition in the lake Varano (Adriatic Sea coast, Italy)
No full textThe zooplankton composition of Lake Varano has been studied from June 2007 to May 2008 considering three sampling
stations (western, central, eastern). A total of 55 zooplankton categories were recognised, with medusae Aurelia aurita as the
main macroscopic species; 43 of them occurred in less than 50% of the 71 samples collected, highlighting the seasonal aspect
of the community. The remaining 12 categories, present in more than 50% of samples, were numerically dominated by the
copepod ‘Non Indigenous Species’ Acartia tonsa (reported here for the first time in the lake), which occurred throughout
the year. Maximal abundance of zooplankton was recorded in the eastern sampling station, while the lowest values were
recorded in the central one. The statistical analysis of data allowed us to establish a not sharp separation of the three
sampling stations, apart from isolated dates. The present zooplankton assemblage showed that about 40% of its components
differed from those recorded in a study of 18 years before. This last comparison is not easily referable to the ongoing climate
warming (the dominant species are of cold temperate origin) and analysis of uninterrupted time series could be useful to
understand the underlying reasons
Aricidea fragilis (Annelida: Paraonidae) in the Mediterranean Sea: overlooked native or alien species?
No full textThe paraonid polychaete Aricidea fragilis Webster, 1879, a typically west-Atlantic species, is reported from the
Mediterranean Sea on the basis of several individuals, from the Adriatic and Tyrrhenian Sea. Its differences with the
other Mediterranean Paraonidae, and in particular with the morphologically close Aricidea suecica meridionalis Laubier &
Ramos, 1974, are briefly discussed. The possible status of A. fragilis as an alien species in European waters is analysed. The
scarcity of historical records, the relatively restricted distribution, and the population dynamics observed in European waters
strongly support the hypothesis of an introduction, despite the wide temporal interval between the first record of the species
in the 1930s and the currently ongoing range expansion and population explosion. Here we precautionarily suggest
considering A. fragilis a cryptogenic species
Oil Extraction from Macrophytes: Effect of Environmental Factors on Efficiency and Oil Quality in Coastal Lagoon
No full textMacrophytes represent interesting matrices for oil extraction with biodiesel production purposes, particularly in eutrophic coastal lagoons. This short note reported results on bio-oil extraction efficiency in two different species of macrophytes in a Mediterranean lagoon (Lesina lagoon, south-eastern Italy), by testing effects of different factors (year, season, species of macrophytes) on oil production and oil quality. Extracted total oils values ranged from 0.65 % (Chara spp.) to 2.35 % (Chaetomorpha linum) and a significant difference (p < 0.01) between the two species was reported in relation to the variability of diene production with seasons. Compared to the available literature, higher oil extraction efficiencies are reported in this paper for the species C. linum, mainly due to the pressure optimization before extractions
Variazioni spazio-temporali del comportamento bentonico e potenziale effetto dell'habitat sedimentario sulla zonizzazione biotica: il caso della laguna di Lesina
No full textLe acque interne del Parco Nazionale del Gargano: un biotopo da conservare e gestire in modo ecosostenibile
No full textFirst record of sinanodonta woodiana (Lea, 1834) in an artificial reservoir in the molise region, Southeast Italy
Full text linkThe occurrence of the Chinese pond mussel Sinanodonta woodiana is reported for the first time in the Molise region (Southeast Italy). Details of the mussel’s invasion history in Italy are also given. A total of 24 S. woodiana specimens were collected after a long drought period in October 2017 from an emerged beach on the southwest side of the Guardialfiera artificial lake and their main morphometric features were quantified. No young individuals were found, only large adults, whose survival could ensure population subsistence in more suitable environmental conditions. The present study provides evidence of a massive die-off affecting invasive bivalves during an extreme climatic event, producing decaying biomass with negative impacts on the water quality of the lake. Further investigations of the population dynamics of this species and the environmental quality of the water body are needed to develop an appropriate management plan in relation to the ecosystem services it delivers
Policheti criptogenici nei mari italiani: caso di Aricidea fragilis (Annelida: Paraonidae)
No full textLo studio e monitoraggio delle specie alloctone in ambiente marino è un elemento di primaria importanza per lo sviluppo di politiche ambientali. Tuttavia, soprattutto con gli invertebrati, non è sempre semplice capire se una specie sia realmente alloctona, o non rappresenti piuttosto un’entità nativa la cui presenza è stata sottostimata. In questo studio si è scelto di studiare la diffusione in Mediterraneo di Aricidea fragilis Webster, 1879, una specie tipica dell’Atlantico occidentale, di cui sono note alcune segnalazioni storiche (Strelzov, 1973; Laubier&Ramos, 1974), ma che negli ultimi anni è stata oggetto di un’ampia espansione demografica principalmente nel Mar Adriatico. Sulla base di dati storici e di dati inediti, con considerazioni sull’ecologia della specie, si tenta di discutere se A. fragilis debba essere considerata alloctona o nativa nei mari italiani. Si tratta, in questo caso, della prima possibile introduzione di un polichete della famiglia Paraonidae
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
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