Oceanologica Acta最新文献

{"title":"Spatial heterogeneity in the distribution of plants and benthic invertebrates in the lagoon of Orbetello (Italy)","authors":"Anna Maria De Biasi ,&nbsp;Lisandro Benedetti-Cecchi ,&nbsp;Lorenzo Pacciardi ,&nbsp;Elena Maggi ,&nbsp;Stefano Vaselli ,&nbsp;Iacopo Bertocci","doi":"10.1016/S0399-1784(02)01226-4","DOIUrl":"10.1016/S0399-1784(02)01226-4","url":null,"abstract":"<div><p>Many studies in marine coastal lagoons have focused on the marine-to-terrestrial gradient as a main source of variation for the structure of assemblages. In this paper, the magnitude of differences among locations arranged along the marine-to-terrestrial gradient of the western lagoon of Orbetello (Grosseto, Italy) was contrasted with the amount of spatial variability occurring among sets of locations that were not positioned along this axis. We propose that if the most important processes influencing assemblages were those associated with the external–internal gradient of the lagoon, as usually supposed, then assemblages should differ more among these locations than among any other locations. To test the above proposition, four locations arranged along the two major axes of the lagoon were established in November 2000. Each location was sampled three times (November 2000, April 2001, August 2001) to test for temporal consistency in spatial patterns. At each time of sampling, three replicate sites were established in each location. This design enabled estimates of spatial variability to be obtained at three scales: among locations hundreds of meters apart, among sites tens of meters apart and among quadrats hundreds of centimeters apart. Non-metric multidimensional scaling (nMDS) ordination plots on abundance data revealed differences among assemblages hundreds of meters apart. Assemblages in the inner part of the lagoon were separated from those closer to the sea inlet, depending on the marine-to-terrestrial gradient. In addition to this pattern, differences also occurred among assemblages hundreds of meters apart, but positioned at a similar distance from the sea. Multifactorial Anovas on abundance of the most common taxa showed significant differences in mean values at the scales of location and site, with patterns changing over time. These results indicated that spatial structure in assemblages was not a distinctive feature of locations arranged along the marine-to-terrestrial gradient in the lagoon of Orbetello. Similar differences also occurred among other sets of locations at the scale of hundreds of meters, regardless of their position in the lagoon.</p></div>","PeriodicalId":100980,"journal":{"name":"Oceanologica Acta","volume":"26 1","pages":"Pages 39-46"},"PeriodicalIF":0.0,"publicationDate":"2003-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/S0399-1784(02)01226-4","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88231864","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Recovery of the macrobenthic community in the Valli di Comacchio, northern Adriatic Sea, Italy","authors":"C. Munari, S. Modugno, F. Ghion, G. Castaldelli, E. Fano, R. Rossi, M. Mistri","doi":"10.1016/S0399-1784(02)01231-8","DOIUrl":"https://doi.org/10.1016/S0399-1784(02)01231-8","url":null,"abstract":"","PeriodicalId":100980,"journal":{"name":"Oceanologica Acta","volume":"60 1","pages":"67-75"},"PeriodicalIF":0.0,"publicationDate":"2003-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75519165","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Relationships between sediments and tissue contamination and allozymic patterns in Hediste diversicolor (Polychaeta Nereididae) in the Pialassa lagoons (north Adriatic Sea)","authors":"Massimiliano Virgilio,&nbsp;Nicola Baroncini,&nbsp;Claudio Trombini,&nbsp;Marco Abbiati","doi":"10.1016/S0399-1784(02)01230-6","DOIUrl":"https://doi.org/10.1016/S0399-1784(02)01230-6","url":null,"abstract":"<div><p>An increasing number of investigations revealed that responses of populations to environmental stressors may be genetically dependent. Occurrence of genetic adaptation to high concentrations of heavy metals in <em>Hediste diversicolor</em><span> local ecotypes has also been hypothesised. Analyses of allozymic patterns are a promising tool for the genetic monitoring of environmental stressors. The aim of this study was to investigate whether the allozymic patterns of </span><em>H. diversicolor</em> could be affected by levels of contamination. Five sites were investigated: four in a polluted brackish habitat, the Pialassa lagoons, and a reference site in the Lamone estuary. Total mercury was used as a tracer of the overall level of contamination. Concentrations of mercury were quantified in both sediments and <em>H. diversicolor</em><span> tissues by means of cold vapour atomic fluorescence spectroscopy. A gradient of mercury concentration in both sediments and </span><em>H. diversicolor</em><span><span> tissues was found. Moreover, significant differences in concentration of mercury were observed among and within sites. Allozyme </span>electrophoresis<span> was used to test the occurrence of genetic differentiation among </span></span><em>H. diversicolor</em><span> samples. A total of 19 putative gene loci were analysed. For six gene loci, significant variability in genotypic and allelic frequencies was detected. Patterns of differentiation, which could be related to the contamination levels, were found at loci LDH, PGI, SDH. Other loci (ALD, FH, HBDH) showed a significant genetic structuring among samples, not related to concentrations of mercury.</span></p></div>","PeriodicalId":100980,"journal":{"name":"Oceanologica Acta","volume":"26 1","pages":"Pages 85-92"},"PeriodicalIF":0.0,"publicationDate":"2003-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/S0399-1784(02)01230-6","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89991825","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Genetic diversity and environmental stress in Italian populations of the cyprinodont fish Aphanius fasciatus","authors":"R. Cimmaruta, F. Scialanca, F. Luccioli, G. Nascetti","doi":"10.1016/S0399-1784(02)01234-3","DOIUrl":"https://doi.org/10.1016/S0399-1784(02)01234-3","url":null,"abstract":"","PeriodicalId":100980,"journal":{"name":"Oceanologica Acta","volume":"48 1","pages":"101-110"},"PeriodicalIF":0.0,"publicationDate":"2003-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86260012","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Genetic structure of bisexual and parthenogenetic populations of Artemia from Italian brackish–hypersaline waters","authors":"Giuseppe Nascetti,&nbsp;Paola Bondanelli,&nbsp;Antonella Aldinucci,&nbsp;Roberta Cimmaruta","doi":"10.1016/S0399-1784(02)01233-1","DOIUrl":"10.1016/S0399-1784(02)01233-1","url":null,"abstract":"<div><p>Eight populations of <span><em>Artemia</em></span><span><span><span> displaying different reproduction modalities (amphigonic vs. parthenogenetic) and ploidies (diploid vs. polyploid) have been collected from Italian salt-works or brackish </span>coastal lagoons<span>, and their genetic structure has been investigated using allozyme </span></span>electrophoresis<span>. The results obtained on genetic differentiation showed that the Tyrrhenian bisexual samples (</span></span><em>A</em>. <em>salina</em><span>) are genetically homogeneous even between populations located in relatively faraway sites (Sardinia–Latium), having a moderate gene flow assisted by migratory waterfowl. The parthenogenetic samples (</span><em>A</em>. <em>parthenogenetica</em><span>) are genetically well differentiated both from the bisexual ones and among them, even when characterised by the same ploidy. Each sample presents few genotypes (i.e. few or single clones have been found in each sampling site), well distinguished from all the others. Further results concern the levels of genetic variability recorded. The parthenogenetic populations have an extremely high level of heterozygosity, due to a remarkable number of loci showing fixed heterozygosity, up to 13 out of 18 analysed. The preliminary data presented here show that some strains of </span><em>A</em>. <em>parthenogenetica</em> have a number of biological features typical of species of hybrid origin: fixed heterozygosity at many loci, parthenogenetic reproduction and genome polyploidisation. While too preliminary to advance a new hypothesis on the origin of <em>A</em>. <em>parthenogenetica</em>, our data suggest that further studies need to be carried out aimed at the research of possible bisexual parental species of <em>A</em>. <em>parthenogenetica</em> suspected hybrid strains.</p></div>","PeriodicalId":100980,"journal":{"name":"Oceanologica Acta","volume":"26 1","pages":"Pages 93-100"},"PeriodicalIF":0.0,"publicationDate":"2003-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/S0399-1784(02)01233-1","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76081302","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Genetic diversity and adaptability of two species of Mugilidae (Teleostei: Perciformes) of the Po river delta coastal lagoons","authors":"R. Papa, F. Marzano, V. Rossi, G. Gandolfi","doi":"10.1016/s0399-1784(02)01235-5","DOIUrl":"https://doi.org/10.1016/s0399-1784(02)01235-5","url":null,"abstract":"","PeriodicalId":100980,"journal":{"name":"Oceanologica Acta","volume":"40 1","pages":"121-128"},"PeriodicalIF":0.0,"publicationDate":"2003-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81373892","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Distribution, persistence and change in the macrobenthos of the lagoon of Lesina (Apulia, southern Adriatic Sea)","authors":"C. N. Marzano, L. Liaci, A. Fianchini, F. Gravina, M. Mercurio, G. Corriero","doi":"10.1016/S0399-1784(02)01229-X","DOIUrl":"https://doi.org/10.1016/S0399-1784(02)01229-X","url":null,"abstract":"","PeriodicalId":100980,"journal":{"name":"Oceanologica Acta","volume":"27 1","pages":"57-66"},"PeriodicalIF":0.0,"publicationDate":"2003-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78833733","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Benthic microbial loop functioning in coastal lagoons: a comparative approach","authors":"Elena Manini,&nbsp;Carla Fiordelmondo,&nbsp;Cristina Gambi,&nbsp;Antonio Pusceddu,&nbsp;Roberto Danovaro","doi":"10.1016/S0399-1784(02)01227-6","DOIUrl":"10.1016/S0399-1784(02)01227-6","url":null,"abstract":"<div><p>Coastal lagoons<span> are highly variable and dynamic systems that have been rarely investigated in terms of benthic microbial loop<span><span>. We present here the results of a comparative study aimed at investigating factors and benthic processes potentially affecting microbial loop functioning in three lagoon systems (Goro, Lesina and Marsala lagoons). The three lagoons were characterised by different geo-morphological, trophic and ecological features. We determined organic matter quantity and biochemical composition, exo-enzymatic activities, bacterial biomass and bacterial carbon production together with heterotrophic nanoflagellate and meiofauna biomass. These variables allowed providing estimates of biomass ratios between different benthic compartments and gathering information on C transfer in different systems. The results of this study indicate that organic matter composition played a primary role on microbial loop ability of channelling C-biomass to higher </span>trophic levels. In coastal lagoons, indeed, quantity and quality of sediment organic matter control rates of organic matter degradation, turnover rates (through breakdown of large macromolecules) and utilisation by benthic heterotrophic organisms (bacterial C production). Exo-enzymatic activities in all lagoons investigated were generally low, when compared to coastal marine systems, and lowest rates were observed in systems characterised by refractory organic pools. Our results indicate that the autotrophic contribution to the biopolymeric carbon pools, which influences the ratio of autotrophic to heterotrophic biomass, is a key factor regulating the functional efficiency of the benthic system. The structure of the benthic microbial loop varied according to the different characteristics of the lagoons: from a classical “detritus sink” system (i.e., the Marsala lagoon, where organic matter was highly refractory), to the “source” system (Lesina lagoon, which displayed an efficient C transfer to higher trophic levels, mediated by benthic bacteria).</span></span></p></div>","PeriodicalId":100980,"journal":{"name":"Oceanologica Acta","volume":"26 1","pages":"Pages 27-38"},"PeriodicalIF":0.0,"publicationDate":"2003-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/S0399-1784(02)01227-6","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72663678","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The sessile benthic community patterns on hard bottoms in response to continental vs. marine influence in northern Adriatic lagoons","authors":"Renato Sconfietti,&nbsp;Agnese Marchini,&nbsp;Anna Occhipinti Ambrogi,&nbsp;Cesare F Sacchi","doi":"10.1016/S0399-1784(02)01228-8","DOIUrl":"10.1016/S0399-1784(02)01228-8","url":null,"abstract":"<div><p>The sessile hard bottoms zoobenthos community was studied in three northern Adriatic lagoons (Venice, Caorle and Grado-Marano). On the basis of previous researches (1993–1994 in Venice; 1997 in Grado-Marano), these lagoons had been subdivided into ecological sectors. The time consistency of such a subdivision has been assessed. The largest number of species was found in the lagoon of Venice, showing a high heterogeneity of environments and an intense shipping traffic, coupled with aquaculture activities that favoured the arrival of exotic species. A very poor community of obligate oligohaline species was found in Caorle. The natural and stable environment of Grado-Marano lagoon, with its large area of freshwater influence, hosted an intermediate number of species. The multi-dimensional scaling ordination plot of 27 representative stations from the three lagoons (samples of July 2000) clearly distinguished a cluster of “estuarine” sites from the remaining ones, that could be classified as “inner lagoon” sites, “vivified lagoon” sites and “lagoon mouth” sites. When compared with past results by Anosim test and Simper analysis, a lesser degree of discrimination between clusters of sites could be observed. In the following year (samples of July 2001), a larger number of sampling stations was considered in Venice and Grado-Marano. The multi-dimensional scaling plot for the community data of Grado-Marano showed fairly recognisable clusters, that substantially repeated those defined in 1997. As far as Venice is concerned, about 25% of the examined stations had shifted towards a different group, compared with those identified in 1993–1994; in particular, the “urban”, “inner lagoon” and “estuarine” sectors and their peculiar assemblages survived only in small areas with unique features of harsh environmental conditions. The progressively enhanced marine influx in all the lagoon sectors (but the ones directly affected by the outflow of the only river still discharging into the lagoon) has, on the one hand, reduced the most evident effects of eutrophication and urban pollution, and on the other, led to a banalisation of the lagoon communities.</p></div>","PeriodicalId":100980,"journal":{"name":"Oceanologica Acta","volume":"26 1","pages":"Pages 47-56"},"PeriodicalIF":0.0,"publicationDate":"2003-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/S0399-1784(02)01228-8","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"99008766","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Life cycles in brackish habitats: adaptive strategies of some polychaetes from the Venice lagoon","authors":"Daniela Prevedelli,&nbsp;Roberto Simonini","doi":"10.1016/S0399-1784(02)01232-X","DOIUrl":"https://doi.org/10.1016/S0399-1784(02)01232-X","url":null,"abstract":"<div><p><span>The life cycle of five species of polychaetes living in the Venice lagoon is analysed with the aim of finding out if some traits can be interpreted as an adaptation to brackish environments<span>. The studied species are characterized by different sizes and reproductive strategies. </span></span><em>Marphysa sanguinea</em> is a large-sized, annual iteroparous species belonging to the Eunicidae family that reproduces without epitokal modification. <em>Perinereis cultrifera</em> and <em>P. rullieri</em><span> are large-sized semelparous species belonging to the Nereididae family: the first reproduce with epitokal metamorphosis, the second do not. </span><em>Ophryotrocha labronica</em> and <em>Dinophilus gyrociliatus</em> are small iteroparous species with semi-continuous reproduction belonging to the Dorvilleidae and Dinophilidae families, respectively. All the species are gonochoric. The larger species often have a sex ratio close to 1:1, while in the smaller ones the sex ratio is biased toward the female sex (2:1 in <em>O</em>. <em>labronica</em> and 3:1 in <em>D</em>. <em>gyrociliatus</em>). Moreover, <em>D</em>. <em>gyrociliatus</em><span> exhibits strong sexual dimorphism: the males are dwarf and short living. All the large-sized species have external fertilization, while the small-sized </span><em>O</em>. <em>labronica</em> and <em>D</em>. <em>gyrociliatus</em><span> exhibit external fertilization with pseudo-copulation and internal fertilization, respectively, that ensure a high reproductive success. All the species produce lecitotrophic eggs, protect young stages from at least some environmental stresses and reduce larval dispersion. The role of the suppression of epitoky and protection structure for developing eggs in limiting the dispersal phase is discussed. All species, independent of reproductive strategies, are characterized by high fecundity and reproductive effort. In the small-sized species, the marked bias of the sex ratio in favour of the female sex and, in </span><em>D</em>. <em>gyrociliatus</em>, the reduction in the size of the male eggs, are significant factors in the increasing rate of the populations, enabling them to tolerate sharp variation in density due to environmental unpredictability.</p></div>","PeriodicalId":100980,"journal":{"name":"Oceanologica Acta","volume":"26 1","pages":"Pages 77-84"},"PeriodicalIF":0.0,"publicationDate":"2003-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/S0399-1784(02)01232-X","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91725580","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}