Phytoplankton distribution and composition off the coast of Galicia (northwest of Spain)

During October 1977, phytoplankton iamples were collected alongwith other hydrographic and biological data from a grid of stationslocated off Galicia (NW of Spain), between the coast and about100 km offshore. Chlorophyll a distribution and phytoplanktoncomposition were studied and related to hydrographic and geographicfeatures of the area. The higher phytoplankton biomasses werefound off the western coast and were conditioned by the presenceof the rias - flooded tectonic valleys of moderate depth functioningas positive estuaries - and the occurrence of coastal upwelling,which allows the injection of nutrient rich water along thebottom of the rias. The qualitative composition of the phytoplanktonreflected principally the influence of the rias but appearedalso to show variability related to the distribution of watermasses. The patterns of circulation of the surface and sub-surfacewaters were likely to reinforce the phytoplankton differencesbetween the northern and western coasts of Galicia.     

Spatiotemporal patterns of marine mammal distribution in coastal waters of Galicia, NW Spain

The spatial and seasonal distribution of cetaceans and possible links with environmental conditions were studied at the Galician continental shelf. Data were collected between February–August 2001 and June–September 2003 during opportunistic surveys onboard fishing boats. Seven species of cetaceans were identified from 250 sightings of 6,846 individuals. The common dolphin (Delphinus delphis) was by far the most frequently sighted and the most widely distributed species. Spatiotemporal trends in cetacean distribution and abundance, and their relationships with environmental parameters (sea depth, SST and chlorophyll-a) were quantified using generalised additive models (GAMs). Results for all cetaceans were essentially the same as for common dolphins alone. Modelling results indicated that the number of common dolphin sightings per unit effort was higher further south. The number of individual common dolphins seen per sighting of this species (i.e. group size) was however higher in the north and west of the study area, higher later in the year and higher in 2001 than in 2003. In contrast, the number of common dolphin calves seen (per sighting of this species) was higher in the south. Models including environmental variables indicated larger common dolphin group sizes in deeper waters and at higher chlorophyll concentrations (i.e. in more productive areas). There was also a positive relationship between survey effort and group size, which is probably an artefact of the tendency of the survey platforms (fishing boats) to spend most time in areas of high fish abundance. Numbers of common dolphin calves per sighting were found to be higher in shallower waters. The results are consistent with common dolphins foraging mainly in deeper waters of the Galician continental shelf, while more southern inshore waters may represent a nursery area.     

Parasites and pathologic conditions of the cockle Cerastoderma edule populations of the coast of Galicia (NW Spain).

A survey of pathological conditions affecting cockle populations of the most economically important natural beds of Galician estuaries in NW Spain was performed. Samples of 30 adult cockles were collected from each of 34 natural beds in the spring of 1999 and processed by histological techniques. Disseminated neoplasia were seen in samples from most of the natural beds, in some cases with a high prevalence. The gregarine Nematopsis sp., larval trematode stages, and branchial extracellular large cysts enclosing bacteria-like microorganisms were the most prevalent parasites. Paravortex cardii, intracellular colonies of rickettsiae-like organisms in digestive and gill epithelium, Pseudoklossia sp. coccidians, Trichodina sp., and other ciliates were frequently seen in the samples. Copepods in gills and intestine and unidentified gregarines in intestine epithelia and surrounding connective tissue were less prevalent and were observed in samples of some natural beds. Large foci of heavy hemocytic infiltration were detected in a few sites only. Cysts of Steinhausia sp. and plasmodia and spores of a haplosporidian were seen in cockles from two localities. Inflammation was frequently observed in the samples. Some of the parasites and pathological conditions could be associated with mortality.     

A red tide off the Myanmar coast: Morphological and genetic identification of the dinoflagellate composition

A red tide composed mainly of two Prorocentrum species was found near Kadan Island, southern Myanmar coast, on March 14, 2012. This is the first record of a red tide in the Myanmar coastal area. The red tide included three different harmful dinoflagellates: Prorocentrum rhathymum, Prorocentrum shikokuense and Alexandrium affine. Strains of these species were successfully cultured and examined with detailed morphological observation and DNA (28S rRNA gene) analyses. The strains were subjected to growth experiments under different temperatures to understand their growth capabilities. The experiments were carried out at four different temperature regimes (15, 20, 25 and 30 °C). A. affine exhibited low tolerance for the low temperature regime (15 °C), despite records of its presence in northern temperate regions, indicating this strain is adapted to the tropical environment in Myanmar. P. rhathymum and P. shikokuense exhibited broad tolerance to all given temperature ranges and showed high division rates, providing the physiological basis to form red tides.     

Seasonal variations in upwelling and in the grazing impact of copepods on phytoplankton off A Coruña (Galicia, NW Spain)

The impact of grazing by copepods on phytoplankton was studied during a seasonal cycle on the Galician shelf off A Coruña (NW Spain). Grazing was estimated by measuring the chlorophyll gut content and the evacuation rates of copepods from three mesh-size classes: 200-500 (small), 500-1000 (medium), and 1000-2000 μm (large). Between February 1996 and June 1997, monthly measurements of water temperature, chlorophyll concentration, primary production rates, and copepod abundance, chlorophyll gut content, and evacuation rates were taken at an 80-m-deep, fixed shelf station. Additionally, the same measurements were collected daily during two bloom events in March and in July 1996. Small copepods were the most abundant through the seasonal cycle. The highest grazing impact, however, was due to the medium and large size classes. Grazing by small copepods exceeded grazing by medium and large copepods only during phytoplankton spring blooms. The impact of copepod grazing (considering all size fractions) was generally low. On average, 2% of the phytoplankton biomass and 6% of the primary production were removed daily by the copepod community. Maximum grazing impact values (9% of the phytoplankton biomass and 39% of the primary production) were found in mid-summer. These results suggest that most of the phytoplankton biomass would escape direct copepod grazing in this upwelling area.     

Prevalence of HPV 16 and HPV 18 Lineages in Galicia,Spain

Genetic variants of human papillomavirus types 16 and 18 (HPV16/18) could differ in their cancer risk. We studied the prevalence and association with high-grade cervical lesions of different HPV16/18 variant lineages in a case-control study including 217 cases (cervical intraepithelial neoplasia grade 2 or grade 3 or worse: CIN2 or CIN3+) and 116 controls (no CIN2 or CIN3+ in two-year follow-up). HPV lineages were determined by sequencing the long control region (LCR) and the E6 gene. Phylogenetic analysis of HPV16 confirmed that isolates clustered into previously described lineages: A (260, 87.5%), B (4, 1.3%), C (8, 2.7%), and D (25, 8.4%). Lineage D/lineage A strains were, respectively, detected in 4/82 control patients, 19/126 CIN3+ cases (OR = 3.1, 95%CI: 1.0–12.9, p = 0.04), 6/1 glandular high-grade lesions (OR = 123, 95%CI: 9.7–5713.6, p<0.0001), and 4/5 invasive lesions (OR = 16.4, 95%CI: 2.2–113.7, p = 0.002). HPV18 clustered in lineages A (32, 88.9%) and B (4, 11.1%). Lineage B/lineage A strains were respectively detected in 1/23 control patients and 2/5 CIN3+ cases (OR = 9.2, 95%CI: 0.4–565.4, p = 0.12). In conclusion, lineages A of HPV16/18 were predominant in Spain. Lineage D of HPV16 was associated with increased risk for CIN3+, glandular high-grade lesions, and invasive lesions compared with lineage A. Lineage B of HPV18 may be associated with increased risk for CIN3+ compared with lineage A, but the association was not significant. Large well-designed studies are needed before the application of HPV lineage detection in clinical settings.     

The distribution of dinoflagellate cysts along the Galician (NW Spain) coast

We have studied the distribution of dinoflagellate cysts along10 Galician rías and part of their adjacent continentalshelf. Cyst abundance in the area averaged 856 cysts ml^–1,which is of the same order of magnitude as those found in otherareas of the western European coast. It was higher in the ríasthan in the shelf, having a very heterogeneous distribution,especially in the former. Cyst assemblages in these two areaswere different, suggesting that differences are due to cystproduction rather than to accumulation. Principal componentanalysis, cluster analysis, distribution of macroscopic characteristicsof cyst populations and distribution of single species suggestthat local factors control the distribution in the rías.Nevertheless, a general pattern that splits the whole area intotwo-to the north and to the south of the ría de Camariñas-canbe distinguished. This latter trend was also observed in theshelf and, in our opinion, It should be attributed to threeconcurrent causes: the effect of different upwelling intensitiesor frequencies, the effect of the different numbers and sizesof the ría in each area, and the effect of the presenceof different water masses in these areas. The cyst distributionof a number of individual species was examined and showed threegeneral groups: species with very restricted distribution, suchas Alexandrium sp2 or Scrippsiella sp4, species with a widespreaddistribution along the rías, such as several Scrippsiellaspecies, and species mainly distributed along the shelf, suchas Gymnodinium catenatum. The distribution of cysts belongingto red tide organisms fits quite well with that of their correspondingmotile phases dunng the three previous years for most of theorganisms studied and also during the 1992–1993 period(7–8 years later), but the role of this resting stagein initiating such blooms seems to be highly variable with species.     

Helminth fauna of the yellow-legged gull Larus cachinnans in Galicia, north-west Spain

Thirty-six helminth species were found in 324 gulls examined during June 1994 to February 1996 from different localities of Galicia: 25 trematodes (Brachylaima sp., Brachylecithum microtesticulatum, Cardiocephaloides longicollis, Cryptocotyle lingua, Cryptocotyle concavum, Diplostomum spathaceum, Echinostephilla virgula, Galactosomum phalacrocoracis, Gigantobilharzia acotylea, Gymnophallus deliciosus, Gynaecotyla longiintestinata, Himasthla elongata, Himasthla quissetensis, Knipowitschiatrema nicolai, Levinseniella (Levinseniella) propinqua, Maritrema gratiosum, Maritrema linguilla, Microphallus primas, Microphallus similis, Ornithobilharzia canaliculata, Parorchis acanthus, Phagicola minuta, Psilostomum brevicolle, Renicola sp. and Stephanoprora denticulata), four cestodes (Alcataenia micracantha, Microsomacanthus ductilis, Tetrabothrius (Oriana) erostris and Wardium cirrosa), six nematodes (Anisakis simplex, Contracaecum rudolphii, Cosmocephalus obvelatus), Eucoleus contortus, Paracuaria adunca and Tetrameres (Tetrameres) skrjabini) and one acanthocephalan (Arhythmorhynchus longicollis). Tetrabothrius erostris was the most prevalent species (79.6%), followed by C. obvelatus (47.8%), C. lingua (37.4%), G deliciosus (30.9%), G. longiintestinata (22.8%), P. adunca (21.9%), B. microtesticulatum (17.6%), E. contortus (14.5%) and M. similis (9.3%). Microphallus similis was the dominant species, with a Berger-Parker index (BP) of 0.32, followed by T. erostris (BP=0.10). All species presented an aggregated dispersion except G. acotylea and G. phalacrocoracis, which showed a random dispersion. Species that seem to have the greatest predilection for specific sites along the intestine are: C. longicollis and A. micracantha (first third), Brachylaima sp., M. similis and G. longiintestinata (last third) and A. longicollis (second half). Eight species are known to be pathogenic to commercially important fish or molluscan species and several are pathogenic to humans.     

Species composition, distribution, and ecological preferences of the ticks of grazing sheep in north-central Spain

The distribution and ecological preferences of tick (Acari: Ixodidae) parasites of grazing sheep in the region of Aragón (north-central Spain) were surveyed on flocks four times a year and mapped into a 5 x 5 km grid. Nine tick species were found. These were species of the Rhipicephalus sanguineus group (about 95% of them Rhipicephalus turanicus Pomerantsev, in 91% of cells of the grid), Rhipicephalus bursa Canestrini & Fanzago (79% of cells), Dermacentor marginatus (Sulzer) (58% of cells), Haemaphysalis punctata Canestrini & Fanzago (74% of cells) and Ixodes ricinus (Linnaeus) 14% of cells. Other species weakly represented in the surveys were Dermacentor reticulatus (Fabricius), Haemaphysalis sulcata Canestrini & Fanzago and Hyalomma m. marginatum Koch. Data on temperature, Normalized Difference Vegetation index (NDVI), topography, vegetation categories and plant productivity were used to build models of distribution and abundance of D. marginatus, H. punctata, R. bursa and R. turanicus. The occurrence models largely incorporated climatic variables and had good discrimination ability (P < 0.0001 for every modelled species, correct classification rate or sensitivity within 0.89 and 0.99), whereas the abundance models had a lower explanatory power. These models are relevant in the understanding of the variables composing the main distribution patterns, but they are unable adequately to predict the density. Abundance models produce good predictions in cells with low tick density, whereas poor correlation is observed in sites with high tick abundance. Several causes may be responsible for this low predictive power of the abundance models. Model output might be sensible to host density, to local farming practices, or to the size of the grid used to refer the results of the survey. In the latter case, small patches may support locally important populations of ticks, influencing largely the results of the survey. These patches of particular abiotic conditions, or supporting large host densities, may have been undetected at the resolution of the survey, thus obscuring the impact of the predictive variables.     

Pigment signatures reveal temporal and regional differences in taxonomic phytoplankton composition off the west coast of Ireland

The composition of phytoplankton assemblages in April, 1998in Galway Bay and during a summer phytoplankton bloom occurringsouthwest of Ireland in August, 1998, was characterized by pigmentsmeasured by high-performance liquid chromatography. Pigmentdata reflecting phytoplankton assemblages dominated by diatomsin Galway Bay and dinoflagellates in the southwest of Irelandwere compared to phytoplankton cell counts. Significant relationshipswere found between the fucoxanthin concentrations and the diatomcell numbers (P < 0.0002 r² 0.63) during April, and betweenfucoxanthin (P < 0.0001 r² 0.79), 19'hexanoyloxyfucoxanthin(P < 0.0001 r² 0.77) concentrations and Gyrodinium aureolumcell numbers during the summer bloom.     

Defining phytoclimatic units in Galicia,Spain, by means of multivariate methods

Abstract. Floristic and climate data from 150 plots in 25 sites in Galicia, Spain, were analysed to test the hypothesis that climate is the major factor governing the distribution of woody plant species. TWINSPAN classification, Detrended Correspondence Analysis and Canonical Correspondence Analysis were applied in successive stages of the data analysis to describe vegetational variation in relation to climatic gradients. Six groups of species were defined, two clearly oceanic (Maritime and Cool Maritime), one mediterranean maritime, and three mediterranean (Cold Mediterranean, Cool Mediterranean and Temperate Mediterranean). An aridity gradient was revealed as the primary factor regulating the distribution of the species considered. This main gradient reflects the transition between the Eurosiberian and Mediterranean bio-geographic regions. The gradient can be characterized by means of the Vernet bioclimatic index. A value ≥ 4 for this index can be taken to define the mediterranean zone in our study area. The mean minimum temperature in the coldest month was the second most influential climatic variable. Partial ordination analysis revealed that the residual variation was insignificant and that the observed variation in vegetation can be fully accounted for by climatic variables.     

Use of direct gradient analysis to study the climate-vegetation relationships in Galicia,Spain

This paper reports a bioclimatic analysis of plant species in Galicia, NW Spain. A set of floristic data obtained from 150 plots located at euclimatopes (sites with monitored climate) was analysed using direct gradient analysis and clustering with respect to the 8 climatic variables thought to play a major role in regulating the distribution of the species considered in the study area. Principal component analysis (PCA) and hierarchical clustering were based on a matrix of species by climatic variables. Indicator taxa for the variables were identified on the basis of their Indicator values (Brisse & Grandjouan 1978) and grouped by cluster analysis. The groups produced were compatible with the results of principal component analysis and the frequential analysis of the species, which identified their phytoclimatic nature. The groups were then characterized by determining their climatic positions and indicator values with respect to the chief climatic variables. The first three PCA axes, which were associated with Oceanity, Mean minimum temperatures and the temperature range in the coldest month, together accounted for 97.2% of the variance of the data.     

Distribution of sub-littoral meiobenthos off Goa coast,India

Vertical and horizontal distribution of meiofauna was studied off Goa coast. Bottom deposit included mainly fine sand and silt. Total number of animals ranged from 250 to 2925/10 cm². Highest faunal density was in the top 6 cm layer. The fauna consisted of two main groups, nematodes and foraminiferans which together formed 60 to 80% of the total meiofauna. Fine sand supported a rich fauna. Interstitial water and organic content of the sediment was found to be the limiting factor in the distribution of meiobenthos.     

A new species of Cytisus Desf. (Fabaceae) from islands off the west coast of Galicia (north-west Iberian Peninsula)

A new species of the section Spartopsis Dumort. of the genus Cytisus Desf. (Fabaceae) is described. The new species, Cytisus insularis , is restricted to the western islands of Galicia (north-west Iberian Peninsula), where it principally colonizes cliffs. A possible recent hybrid origin for these populations is considered but rejected in view of the results of experimental tests of pollen viability and seed germination. Characters permitting discrimination from the most similar taxa are detailed, and possible relationships with the other species of the section are discussed.     

Environmental Determinants of the Occurrence and Distribution of Vibrio parahaemolyticus in the Rias of Galicia, Spain

Infections associated with Vibrio parahaemolyticus on the coast of Galicia (in northwestern Spain) were reported to be linked to large outbreaks of illness during 1999 and 2000. Little information is available about the ecological factors that influence the emergence of V. parahaemolyticus infections in this temperate region. We carried out a 3-year study to investigate the occurrence and distribution of V. parahaemolyticus at 26 sites located in the four main rias of Galicia in association with environmental and oceanographic variables. V. parahaemolyticus was detected in all the areas investigated and throughout the complete period of study with an overall incidence of 12.5%. Salinity was the primary factor governing the temporal and spatial distribution of V. parahaemolyticus, whereas seawater temperature had a secondary effect and only modulated the abundance in periods and areas of reduced salinities. Higher occurrence of V. parahaemolyticus was observed during periods of lower salinity in autumn, with a total of 61 positive samples (18%) and a mean density of 1,234 most probable number/100 g. V. parahaemolyticus was primarily detected in areas of reduced salinity close to freshwater discharge points, where it was found in up to 45% of the samples. Characterization of the isolates obtained from the study resulted in the first identification of two pathogenic tdh-positive strains of V. parahaemolyticus recovered from the marine environment in Galicia. These isolates showed serotypes identical to and DNA profiles indistinguishable from those of the clinical clone of V. parahaemolyticus dominant in infections in Spain in the last 10 years.     

Influence of the Agulhas Current on the distribution of lanternfish larvae off the southeast coast of Africa

Spatial and temporal distribution patterns of lanternfish larvaealong the southeast coast of Africa were analysed in relationto oceanographic conditions. Investigations werebased on theplankton collections made during winter, spring and summer monthsof 1990–1991. The warm southward-flowing Agulhas Currentis the dominant large-scale oceanographic feature in the area.The number of species of myctophid larvae collected per cruiseranged from 35 to 38. The most abundant species differed fromone season to the other.Afew species showed marked seasonalityin their occurrence, e.g. Scopelopsis multipunclatiis only appearedin winter and Hygophum hygomii showed the highest abundancesin winter. The majority of species occurred in relatively lowconcentrations during all three periods. Relatively large concentrationsof lanternfish larvae of most species sometimes occurred veryclose inshore (especially in the north of thestudy area) inwater depths of 50–100 m. This was related to shorewardintrusions ofAgulhas Current surface water. Low numbers of larvaeof few species appeared on the inshore shelf of the southernsector of the study area, where cold central Indian Ocean wateris forced onto the shelf by kinematic upwelling.     

Unemployment and labor migration in rural Galicia (Spain)

This article focuses on the difficulty of entering into—and literally getting back and forth to—the waged labor market for adolescent and young adult workers from rural parts of Galicia, a region that has experienced a prolonged history of persistently high levels of unemployment. Unemployment is one of the most serious issues facing Spain, other countries of the EU, and states all over the world. In Spain, for the population of workers under 30, this problem is at staggeringly high levels that have reached 50 % plus in the last few years of the current crisis but has been longstanding. So, too, has labor migration to and from rural Galician households. This article takes a broad approach to the analysis of labor mobility, including daily commuting as well as longer distance and longer duration labor migration. It considers the role of state and EU policies over time in instituting, supporting, or discouraging different geographical trajectories and forms of movement for young adult “wage seekers” from rural Galician households.     

Characterization by enzyme electrophoresis of specimens of the genus Helicometra (Trematoda, Opecoelidae) from fish caught off the coast of northwest Spain

Species within the genus Helicometra are difficult to distinguish on morphological grounds alone, and are best discriminated with the aid of biochemical techniques. In the work reported here, the electrophoretic mobility of malate dehydrogenase isoenzyme of the Mdh-1 locus was used to characterize 375 individuals of Helicometra obtained from various teleost species (Anguilla anguilla, Conger conger, Gobius niger or Ciliata mustela) caught off the coast of northwest Spain. The results suggest that all specimens belong to only one species, probably H. fasciata. Observed genotype frequencies did not differ from those expected under the assumptions of Hardy-Weinberg equilibrium, even when the genic frequencies differ considerably respecting a Mediterranean population.     

Winter circulation weather types and hospital admissions for respiratory diseases in Galicia,Spain

The link between various pathologies and atmospheric conditions has been a constant topic of study over recent decades in many places across the world; knowing more about it enables us to pre-empt the worsening of certain diseases, thereby optimizing medical resources. This study looked specifically at the connections in winter between respiratory diseases and types of atmospheric weather conditions (Circulation Weather Types, CWT) in Galicia, a region in the north-western corner of the Iberian Peninsula. To do this, the study used hospital admission data associated with these pathologies as well as an automatic classification of weather types. The main result obtained was that weather types giving rise to an increase in admissions due to these diseases are those associated with cold, dry weather, such as those in the east and south-east, or anticyclonic types. A second peak was associated with humid, hotter weather, generally linked to south-west weather types. In the future, this result may help to forecast the increase in respiratory pathologies in the region some days in advance.