229 research outputs found
Assessment of the ecological quality (EcoQ) of the Venice lagoon usingthe structure and biodiversity of the meiofaunal assemblages
partially_open3noTransitional Environments (TEs) have been deeply modified to meet human requirements, and for thisreason are currently ranked among the most endangered aquatic ecosystems. The Adriatic basin hosts alarge number of TEs of which the Lagoon of Venice is the largest one, but information on its meiofauna arevery dated or focused to localized areas. The present study is the first to document the spatial distributionof meiofauna in the whole Venice lagoon. Furthermore, the health status of the TE of Venice has beenassessed by means of several faunal parameters (richness, diversity indices, structure of the entire meio-faunal assemblage and only rare taxa). All the univariate meiofaunal parameters (i.e. richness, diversityindices, Ne:Co ratio) were consistent in highlighting the worst ecological quality of the Porto Margheradistrict. Instead, the structure of the entire meiofaunal assemblage as well as that of rare taxa seemed todetect variations not directly related to pollution and likely due to the different hydrodynamic conditionsof Lido and Malamocco inlets. On the basis of our results, we have also critically discussed the usefulnessof the various faunal parameters in the monitoring assessment of the TEs.openSemprucci, Federica; Balsamo, Maria; Sandulli, RobertoSemprucci, Federica; Balsamo, Maria; Sandulli, Robert
Meiobenthos and nematode assemblages from different deep-sea habitats of the Strait of Sicily (Central Mediterranean Sea)
Much attention is currently devoted at upgrading our knowledge on biodiversity and functioning of deep water ecosystems. Information is constantly enriched by researchers, even from basins as the long-studied Mediterranean Sea. In such a perspective, we studied meiobenthic and nematode communities inhabiting muddy sediments from three different habitats at bathyal depths in the Strait of Sicily: a cold-water coral site (CS) in the Maltese Coral Province, a muddy bottom in the same area (MS), and a hydrocarbon imprinted pockmark site (PS) in the Gela Basin. The average meiofauna density at CS (1343 ind/10 cm2) and MS (1804 ind/10 cm2) is much higher than that reported in literature for similar habitats; it is also markedly more elevated than that recorded at PS (224 ind/10 cm2). Although nematodes of the three sites show different abundances, they share similar assemblage structure. Nematodes (avg. 86%) and copepods (avg. 9.3%) were the most abundant meiofaunal taxa at all sites followed by annelids, kinorhynchs and turbellarians. Nematodes were composed by 21 families and 46 genera, with Terschellingia, as most abundant genus (12.4%), followed by Microlaimus (11%), Daptonema (11%), Thalassomonhystera (10.8%), Acantholaimus (9.5%) and Sabatieria (8.7%). The genera Thalassomonhystera, Terschellingia, Microlaimus, Daptonema, Chromadorita, Sabatieria, and Anticoma display a dominance in at least one station. The taxonomic structure of meiofaunal communities of the studied sites is rather similar but differences in relative abundance are evident
The red coral populations of the gulfs of Naples and Salerno: human impact and deep mass mortalities
Riforma universitaria
La l. 30.12.2010, n. 240, che ha profondamente riformato l\u2019ordinamento universitario, mira ad elevare la concorrenza e il merito nelle universit\ue0, riducendo l\u2019autoreferenzialit\ue0 delle componenti accademiche sia nelle scelte strategiche e di governo del sistema sia in ordine ai meccanismi di reclutamento dei professori. La riforma, al contempo, sembra aver compresso in modo significativo l\u2019autonomia universitaria. \uc8 presto, tuttavia, per formulare un giudizio sulla l. n. 240/2010: per un bilancio degli effetti della stessa occorrer\ue0 attendere la conclusione del complesso processo di attuazione \uaba cascata\ubb. La legge, infatti, richiede, da un lato, che gli atenei adeguino i loro statuti e, dall\u2019altro, che il governo adotti numerosi regolamenti e decreti di attuazione
Meiofauna and nematode diversity in some Mediterranean subtidal areas of the Adriatic and Ionian Sea
Sediments of three different subtidal areas (15-705 m depth) of the Italian coasts (Manfredonia, Brindisi and Gallipoli) were investigated to study meiofauna and nematode composition. The nematodes were identified to the genus level and their abundances compared using multivariate analysis. Our data showed an evident depth gradient in meiofauna abundance: the shallowest sites had more diverse and abundant meiobenthic communities than the deeper ones. Nematodes were the dominant taxon (83-100%) at all sites, followed by Copepoda (0.5-8%). Sabatieria, Astomonema, Dorylaimopsis, Terschellingia and Daptonema were among the dominant nematode genera in the three areas. Nematode genus H’ diversities were not significantly dissimilar, though at community level some differences were detected among the study areas. The greatest differences were observed in the comparison of the communities from Manfredonia and Gallipoli. Furthermore, there was a difference between shallow (Astomonema, Dorylaimopsis, Sabatieria and Terschellingia)
Occurrence of <i>Chromadorita regabi</i> sp. nov. (Nematoda: Adenophorea), a nematode egg predator of <i>Alvinocaris muricola</i> (Crustacea: Decapoda: Caridea: Alvinocarididae) from a deep cold seep area of the Gulf of Guinea
Several individuals belonging to a new species of the genus Chromadorita (Nematoda: Adenophorea) were collected in a cold-seep area in the Gulf of Guinea during two French cruises: BIOZÄIRE 2 (2001) and BIOZAÏRE 3 (2003–2004) on board the R/V L’Atalante. In this area, rich chemosynthetic benthic communities have been discovered at 3150 m depth in the large pockmark field named Regab. Chromadorita regabi sp. nov. was found among the eggs in ovigerous specimens of the shrimp Alvinocaris muricola. The combination of long size (1500–2200 µm), nine strong preanal papillae and relatively small dorsal tooth with weak musculature distinguishes this species from all known congeneric ones. An identification key to all known species of Chromadorita is provided
Antarctic Special Protected Area 161 as a Reference to Assess the Effects of Anthropogenic and Natural Impacts on Meiobenthic Assemblages
The Antarctic region is usually considered a pristine area. Nevertheless, regional warming
effects and increasing human activities, including the presence of several research stations, are
inducing considerable environmental changes that may affect the ecosystem’s functions. Therefore,
during the XXXIII Antarctic expedition, we carried out an investigation in Terra Nova bay (Ross
Sea), close to the Antarctic Specially Protected Area (ASPA) n.161. In particular, we compared the
effects of two different types of impacts on the meiobenthic assemblages: anthropogenic impact
(AI), associated with the activity of Mario Zucchelli Research Station (MZS), and natural impact
(NI) attributable to a large colony of Adélie penguins (Pygoscelis adeliae) in Adelie Cove. For each
impacted site, a respective control site and two sampling depths (20 and 50 m) were selected. Several
environmental variables (pH, dissolved oxygen, major and minor ions, heavy metals, organic load,
and sediment grain size) were measured and analysed, to allow a comprehensive characterization
of the sampling areas. According to the criteria defined by Unites States Environmental Protection
Agency (US EPA 2009), heavy metal concentrations did not reveal critical conditions. However,
both the MZS (AI20) and penguin colony (NI20) sites showed higher heavy metal concentrations,
the former due to human activities related to the Italian research station, with the latter caused by
the penguins excrements. Meiobenthic richness and abundance values suggested that the worst
ecological condition was consistently related to the Adélie penguins colony. Furthermore, the higher
contribution of r-strategists corroborates the hypothesis that the chronic impact of the penguin
colonies may have stronger effects on the meiobenthos than the human activities at the MZS. Food
is not limited in shallow Antarctic bottoms, and microscale differences in primary and secondary
production processes can likely explain the greater spatial heterogeneity, highlighted both by the
univariate and multivariate attributes of meiobenthic assemblage (i.e., richness, diversity, abundance,
whole structure assemblage, and rare taxa) at the deeper stations. As reported in other geographical
regions, the assemblage structure of rare meiobenthic taxa is confirmed to be more susceptible to
environmental variations, rather than the whole assemblage structure
In situ recordings of large gelatinous spheres from NE Atlantic, and the first genetic confirmation of egg mass of Illex coindetii (Vérany, 1839) (Cephalopoda, Mollusca)
In total, 90 gelatinous spheres, averaging one meter in diameter, have been recorded from ~ 1985 to 2019 from the NE Atlantic Ocean, including the Mediterranean Sea, using citizen science. More than 50% had a dark streak through center. They were recorded from the surface to ~ 60–70 m depth, mainly neutrally buoyant, in temperatures between 8 and 24°C. Lack of tissue samples has until now, prohibited confirmation of species. However, in 2019 scuba divers secured four tissue samples from the Norwegian coast. In the present study, DNA analysis using COI confirms species identity as the ommastrephid broadtail shortfin squid Illex coindetii (Vérany, 1839); these are the first confirmed records from the wild. Squid embryos at different stages were found in different egg masses: (1) recently fertilized eggs (stage ~ 3), (2) organogenesis (stages ~ 17–19 and ~ 23), and (3) developed embryo (stage ~ 30). Without tissue samples from each and every record for DNA corroboration we cannot be certain that all spherical egg masses are conspecific, or that the remaining 86 observed spheres belong to Illex coindetii. However, due to similar morphology and size of these spheres, relative to the four spheres with DNA analysis, we suspect that many of them were made by I. coindetii
PROSPETTIVE E CRITICITÀ SUL RUOLO DEL BENTHOS MEDITERRANEO NELLA DIRETTIVA SULLA MARINE STRATEGY
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