Abollo E.,Centro Tecnologico Del Mar
Diseases of Aquatic Organisms | Year: 2014
Bonamiosis is a disease affecting various oyster species and causing oyster mass mortalities worldwide. The protozoans Bonamia exitiosa and B. ostreae (Haplosporidia) are in - cluded in the list of notifiable diseases of the World Organisation for Animal Health as the causative agents of this disease. Although the geographic range of both species was considered different for years, both species are now known to co-occur in some European areas affecting the same host, Ostrea edulis, which strengthens the need of species-specific methods to unequivocally identify the species of Bonamia. An oligonucleotide probe for specific detection of B. Exitiosa (BEX-ITS) was designed to be used in in situ hybridisation (ISH) assays. ISH assay with BEX-ITS probe showed species-specificity and more sensitivity than traditional histology to visualise the parasite inside host tissue. ISH assay showed that the oyster gonad was the area where the parasite was most frequently located, and was the exclusive organ of infection in some oysters. A recommendation arising from the study is that more than 1 organ (including gonad and gills) should be used for PCR-based diagnosis of B. Exitiosa, to maximise the sensitivity. © Inter-Research 2014.
Sieiro P.,Centro Tecnologico del Mar |
Otero J.,CSIC - Institute of Marine Research |
Guerra A.,CSIC - Institute of Marine Research
Hydrobiologia | Year: 2014
We contrasted histological characteristics with a macroscopic maturity scale in Octopus vulgaris. Seven histological stages of maturation were identified, and a stereological method was used to develop a new histological maturity index (HMI). This index was related to the gonadosomatic index giving the possibility to estimate the histological stage of individual octopus without sampling the gonads. However, the existing macroscopic maturity scale produced some degree of overlap along the range of HMI, suggesting that this macroscale at this moment might be just good enough to separate immature from fully mature individuals. A histological maturity criterion based on the presence of a larger proportion of folding oocytes compared to earlier microstages resulted in a size at maturity of 1.5 kg. However, using two different macroscopic criteria, size at maturity was 1.3 and 2.3 kg. The estimate of size at maturity is therefore sensitive to the maturity criteria used. The maturation cycle of female O. vulgaris was seasonal, peaking in spring months and reaching a maximum of reproductive activity in April independently of the maturation criteria used. Oogenesis was reviewed and found to be an asynchronic process. Our results suggest that there is a need to examine all these issues in other cephalopod species. © 2014 Springer International Publishing Switzerland.
Miguez B.M.,Centro Tecnologico del Mar |
Testut L.,LEGOS |
Woppelmann G.,University of La Rochelle |
Woppelmann G.,French National Center for Scientific Research
Scientia Marina | Year: 2012
Considerable efforts are being made worldwide to upgrade tide gauge networks using new technologies. Because of the unique location of the Kerguelen Islands, the measurement of sea level there has received particular attention, with up to four systems equipped with modern sensors functioning simultaneously (two pressure tide gauges, a radar tide gauge, and a GPS-equipped buoy). We analysed and compared the sea level data obtained with these systems from 2003 to 2010, together with a time series of tide pole observations. This is the first time that a multi-comparison study with tide gauges has been undertaken over such a long time span and that the stability of modern radar tide gauges has been examined. The multi-comparison enabled us to evaluate the performance of the tide gauges in several frequency ranges, identify errors and estimate their magnitude. The drift of the pressure sensors (up to 8.0 mm/yr) was found to be one of the most relevant sources of systematic error. Other sources of difference such as clock drift, scale error and different locations of the instruments were also detected. After correcting the time series of sea level for these errors we estimated an upper bound for the radar instrumental error in field condition at ~0.3 cm.
Gouriou T.,CNRS Coastal and Marine Environment Laboratory |
Martin Miguez B.,CENTRO Tecnologico del Mar |
Woppelmann G.,CNRS Coastal and Marine Environment Laboratory
Continental Shelf Research | Year: 2013
This paper describes the work of sea level data rescue, digitization, reduction to a common vertical reference and quality control leading to the reconstruction of a time series for the Atlantic NW coast of France (Pertuis d'Antioche). A total of 14 sea level data sets were merged to build a consistent composite time series of monthly and annual mean sea levels spanning 188 years (1824-2011).The estimation of a linear trend for this time series yields a relative mean sea level rise for the region of 1.3±0.1mmyr-1 for the whole study period, and 1.9±0.2mmyr-1 for the 20th century, consistent with previous studies in the region. This work evidences the importance of data archaeology in the pursuing of historical information useful for sea level studies, which can be relevant for climate research and coastal management amongst other applications. © 2013 Elsevier Ltd.
Fortunato A.B.,National Laboratory for Civil Engineering |
Li K.,National Laboratory for Civil Engineering |
Bertin X.,CNRS Coastal and Marine Environment Laboratory |
Rodrigues M.,National Laboratory for Civil Engineering |
Miguez B.M.,Centro Tecnologico Del Mar
Ocean Engineering | Year: 2016
Extreme sea levels along the Atlantic Iberian coast are determined through the development and application of a numerical model for tides and surges, followed by a statistical analysis of the model results. A recent statistical method is assessed using 131 years of data from the Brest tide gauge, and the number of years of data required for an accurate statistical analysis is estimated. The statistical method is extended to consider tide-surge interactions, but they are shown to be small in the study region. The model covers a large portion of the NE Atlantic, with a 250 m resolution in the Portuguese shelf. In the Iberian shelf, root mean square errors of tides are of the order of 5 cm, and extreme sea levels are underestimated by about 10 cm. Differences between sea level statistics obtained from model output and observations are of the order of 5 cm in the study region. Simulation of tides and surges between 1980 and 2010, followed by a statistical analysis of the results, provide the extreme levels along the Iberian Atlantic coast for different return periods. Results reveal the increase of extreme sea levels from south to north and the importance of local effects. © 2015 Elsevier Ltd.
Santamaria-Gomez A.,Instituto Geografico Nacional |
Santamaria-Gomez A.,University of La Rochelle |
Gravelle M.,University of La Rochelle |
Collilieux X.,IGN |
And 6 more authors.
Global and Planetary Change | Year: 2012
This study aims to correct for long-term vertical land motions at tide gauges (TG) by estimating high-accurate GPS vertical velocities at co-located stations (GPS@TG), useful for long-term sea-level change studies and satellite altimeter drift monitoring. Global Positioning System (GPS) data reanalyses are mandatory when aiming at the highest consistency of the estimated products for the whole data period. The University of La Rochelle Consortium (ULR) has carried out several GPS data reanalysis campaigns with an increasing tracking network, an improving processing strategy and the best methodology. The geodetic results from the latest GPS velocity field estimated at ULR (named ULR5) are presented here. The velocity field includes 326 globally distributed GPS stations, from which 200 are GPS@TG (30% more than previous studies). The new GPS data processing strategy, the terrestrial frame definition and the velocity estimation procedures are described. The quality of the estimated vertical velocities is empirically assessed through internal and external velocity comparisons, including the analysis of the time-correlated noise content of the position time series, to be better than 0.6. mm/yr (2 sigma). The application of this velocity field is illustrated to appraise to what extent vertical land motions contaminate the estimates of satellite altimetry drifts. The impact on the altimeter-derived sea level trends was evaluated to be up to 0.6. mm/yr. Worldwide TGs were grouped into regions in order to explore long-term spatial sea level variability in the rates of sea level change. By taking into account the vertical land motion of the tide gauges, the dispersion of the observed sea level rates within each region was reduced by 60%. Long-term regional mean sea level variations up to 70% from the global mean were found. © 2012 Elsevier B.V.
Gomez-Brandon M.,University of Vigo |
Lazcano C.,Centro Tecnologico del Mar |
Lores M.,Laboratorio Of Investigacion Y Desarrollo Of Soluciones Analiticas Lidsa |
Dominguez J.,University of Vigo
Journal of Hazardous Materials | Year: 2011
The winery industry generates vast amounts of organic waste during the various stages of wine production. Among the possible methodological alternatives available for its treatment, vermicomposting is one of the best-known processes for the biological stabilization of solid organic wastes by transforming them into safer and more stabilized materials suitable for application to soil. In this study we carried out a mesocosm experiment to evaluate the effectiveness of the active phase of vermicomposting for the stabilization of grape marc, an enriched lignocellulosic by-product obtained after the grape crushing and pressing stages in wine production. For this we analysed the chemical, biochemical and microbiological properties of the product resulting from this phase, in comparison with those in a control treatment. Earthworm activity reduced the abundance of both bacterial and fungal PLFA biomarkers. Decreases in microbial activity and in protease and cellulase activities were also attributed to the presence of earthworms. The differences in microbial communities were accompanied by a reduction in the labile C pool and the cellulose content. These results indicate that earthworms played a key role in the stabilization of the grape marc in the short-term, via its effects on organic matter decomposition and microbial biomass and activity. © 2011 Elsevier B.V.
Lazcano C.,University of Vigo |
Lazcano C.,Centro Tecnologico del Mar |
Revilla P.,Mision Biologica de Galicia CSIC |
Malvar R.A.,Mision Biologica de Galicia CSIC |
Dominguez J.,University of Vigo
Journal of the Science of Food and Agriculture | Year: 2011
BACKGROUND: Vermicompost has been proposed as a valuable fertilizer for sustainable agriculture. The effects of vermicompost on yield and quality of sweet corn were evaluated in this study. In two field trials, sweet corn plants were grown under (i) a conventional fertilization regime with inorganic fertilizer, and integrated fertilization regimes in which 75% of the nutrients were supplied by the inorganic fertilizer and 25% of the nutrients were supplied by either (ii) rabbit manure, or (iii) vermicompost. All three types of fertilization regime were supplied at two doses. Two pairs of nearly isogenic sweet corn hybrids homozygous for sugary1 and shrunken2 mutants were included in the trials to explore fertilizer × genotype interactions. Growth, yield and ear quality of the plants were evaluated in relation to the three fertilization regimes. RESULTS: In general, the integrated regimes yielded the same productivity levels as the conventional treatment. Moreover, both vermicompost and manure produced significant increases in plant growth and marketable yield, and also affected the chemical composition and quality of the marketable ear. Nevertheless, most of the observed effects of the organic fertilizers were genotype-dependent. CONCLUSION: The results confirm that the use of organic fertilizers such as vermicompost has a positive effect on crop yield and quality. Nevertheless, these effects were not general, indicating the complexity of the organic amendment-plant interactions and the importance of controlling genetic variation when studying the effects of vermicompost on plant growth. © 2011 Society of Chemical Industry.
Aira M.,University of Vigo |
Gomez-Brandon M.,University of Vigo |
Gomez-Brandon M.,Lund University |
Lazcano C.,University of Vigo |
And 3 more authors.
Soil Biology and Biochemistry | Year: 2010
We studied the microbial communities in maize (Zea mays) rhizosphere to determine the extent to which their structure, biomass, activity and growth were influenced by plant genotype (su1 and sh2 genes) and the addition of standard and high doses of different types of fertilizer (inorganic, raw manure and vermicompost). For this purpose, we sampled the rhizosphere of maize plants at harvest, and analyzed the microbial community structure (PLFA analysis) and activity (basal respiration and bacterial and fungal growth rates). Discriminant analysis clearly differentiated rhizosphere microbial communities in relation to plant genotype. Although microorganisms clearly responded to dose of fertilization, the three fertilizers also contributed to differentiate rhizosphere microbial communities. Moreover, larger plants did not promoted higher biomass or microbial growth rates suggesting complex interactions between plants and fertilizers, probably as a result of the different performance of plant genotypes within fertilizer treatments, i.e. differences in the quality and/or composition of root exudates. © 2010 Elsevier Ltd.
Suris-Regueiro J.C.,University of Vigo |
Santiago J.L.,Centro Tecnologico del Mar
Marine Policy | Year: 2014
The management of marine ecosystems requires adequate knowledge of both environmental and human dimensions, as well as their interrelationships. In this study, the aquaculture and fisheries activities are analyzed in one of most important fishing regions in Europe, Galicia (NW Spain). In particular, the intensity and characteristics of the fishing dependency are evaluated in terms of income and employment. Thus, nine marine economic activities for nine Maritime Zones have been defined, considering the social and economic relevance of the provided ecosystem services to these communities. This paper highlights the entire Galician coast as fishing-dependent, independently of the urbanization level. Furthermore, the contribution of different fishery segments to the income and employment of these coastal communities is reviewed, including fluctuations on whether the activity is small or large-scale. Finally, this study establishes a strong relationship among the marine activities, which generate most employment, and the regulatory framework of the Regional Government. Therefore, the conclusions are relevant to design and implement policies that affect Galicia[U+05F3]s Region and all its related marine ecosystems. © 2014 Elsevier Ltd.