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Sample records for periwinkles littorina irrorata

  1. Effects of Deepwater Horizon Oil on the Movement and Survival of Marsh Periwinkle Snails (Littoraria irrorata).

    Science.gov (United States)

    Garner, T Ross; Hart, Michael A; Sweet, Lauren E; Bagheri, Hanna T J; Morris, Jeff; Stoeckel, James A; Roberts, Aaron P

    2017-08-01

    The Deepwater Horizon (DWH) oil spill resulted in the release of millions of barrels of oil into the Gulf of Mexico, and some marsh shorelines experienced heavy oiling including vegetation laid over under the weight of oil. Periwinkle snails (Littoraria irrorata) are a critical component of these impacted habitats, and population declines following oil spills, including DWH, have been documented. This study determined the effects of oil on marsh periwinkle movement and survivorship following exposure to oil. Snails were placed in chambers containing either unoiled or oiled laid over vegetation to represent a heavily impacted marsh habitat, with unoiled vertical structure at one end. In the first movement assay, snail movement to standing unoiled vegetation was significantly lower in oiled chambers (oil thickness ≈ 1 cm) compared to unoiled chambers, as the majority (∼75%) of snails in oiled habitats never reached standing unoiled vegetation after 72 h. In a second movement assay, there was no snail movement standing unoiled structure in chambers with oil thicknesses of 0.1 and 0.5 cm, while 73% of snails moved in unoiled chambers after 4h. A toxicity assay was then conducted by exposing snails to oil coated Spartina stems in chambers for periods up to 72 h, and mortality was monitored for 7 days post exposure. Snail survival decreased with increasing exposure time, and significant mortality (∼35%) was observed following an oil exposure of less than 24 h. Here, we have shown that oil impeded snail movement to clean habitat over a short distance and resulted in oil-exposure times that decreased survival. Taken together, along with declines documented by others in field surveys, these results suggest that marsh periwinkle snails may have been adversely affected following exposure to DWH oil.

  2. Uptake and depuration of 131I by the edible periwinkle Littorina littorea: uptake from labelled seaweed (Chondrus crispus)

    International Nuclear Information System (INIS)

    Wilson, R.C.; Vives i Batlle, J.; McDonald, P.; Parker, T.G.

    2005-01-01

    Uptake and depuration experiments of 131 I from labelled seaweed (Chondrus crispus) by the edible periwinkle Littorina littorea have been performed. Radioiodine concentrations in winkles during uptake followed first-order kinetics with an uptake half-time of 1 day, and a calculated equilibrium concentration (C ∞ ) of 21 000 Bq kg -1 resulting in a transfer factor of 0.07 with respect to the labelled seaweed used as food. For depuration, a biphasic sequence with biological half-lives of 1 and 24 days was determined. The results suggest that in general, iodine turnover in periwinkles is slower than observed for other molluscs (monophasic biological half-lives in the order of 2-3 days). Both environmental media, food and seawater, can be significant sources of radioiodine for the winkle

  3. Occurrence of 210Po in periwinkle (Littorina undulata, Gray, 1839) collected from Kudankulam (Gulf of Mannar (GOM), Southeast coast of India)

    International Nuclear Information System (INIS)

    Sunith Shine, S.R.; Feroz Khan, M.; Godwin Wesley, S.

    2013-01-01

    Highlights: • Polonium-210 was quantified in the periwinkle Littorina undulata. • Smaller-sized periwinkles displayed higher Polonium-210. • Marked variation in 210 Po activity between season and sampling site. • The internal dose rate estimated using ERICA Assessment Tool. • The daily intake and committed effective dose estimated. -- Abstract: Polonium-210 activity concentration was analysed in the whole body tissue of periwinkle Littorina undulata collected from intertidal rocky shore along Kudankulam coast. We carried out the study for a period of 12 months (2011–2012) focusing on three seasons. 210 Po was found non-uniformly distributed among the periwinkles depending on the allometry. The 210 Po accumulation showed a significant difference between seasons (p 210 Po compared to larger ones (p 210 Po varied from 13.5 to 58.9 Bq/kg (wet). The activity of 210 Po was also quantified in seawater and intertidal sediments to calculate the biological concentration factor (BCF) and radiation dose rate. The dose rate to the winkles was performed using ERICA Assessment Tool and it was within the prescribed limit. The intake of 210 Po through periwinkles delivered an effective dose in the range of 2.2–9.6 μSv/y to human beings

  4. Sensitivity to cadmium along a salinity gradient in populations of the periwinkle, Littorina littorea, using time-to-death analysis

    International Nuclear Information System (INIS)

    Wolf, Hans de; Backeljau, Thierry; Blust, Ronny

    2004-01-01

    In this study, we assessed the combined effect of Cd concentration and salinity, on Cd uptake and mortality rate of Littorina littorea, collected along a salinity and pollution gradient in the Western Scheldt estuary (The Netherlands). Animals kept at their field salinity levels were exposed to three Cd concentrations (i.e. 10, 40 and 320 μM), while animals kept in 10 μM of Cd were subjected to five salinity treatments (i.e. 15, 20, 25, 30 and 35%o). Mortality was recorded every 24 h and Cd body burdens were measured with ICP-AES. Time-to-death data were analysed via Cox proportional hazard models, including the co-variates 'site-Cd treatment' in the Cd experiment and 'site-salinity treatment' in the salinity experiment. 'Cd-treatment' and 'field-salinity' affected mortality rates significantly in the Cd experiment, such that the mortality risk increased by 2.3 times when salinity was lowered from 35 to 15%o, while it decreased by 19.7 times when Cd dropped from 320 to 10 μM. 'Site' did not significantly affect the mortality risk in the salinity experiment but affected time-to-death via its interaction with the 'salinity-treatment'. Generally, mortality did not occur at a given threshold Cd tissue level, but changed over time and treatments, in function of the site. The results demonstrate the importance of the animals' environmental history and illustrate the usefulness of time-to-death analyses in ecotoxicological experiments

  5. A weight-of-evidence approach to assessing the ecological impact of organotin pollution in Dutch marine and brackish waters; combining risk prognosis and field monitoring using common periwinkles (Littorina littorea).

    Science.gov (United States)

    Schipper, Cor A; Smit, Mathijs G D; Kaag, Nicholas H B M; Dick Vethaak, A

    2008-08-01

    In the present study an integrated ecological risk assessment based on multiple lines of evidence (LOEs) was evaluated in order to better assess the risk from TBT in Dutch harbours and open coastal waters. On the basis of spatial distributions of measured tributyltin (TBT) concentrations in sediments and suspended matter, predictions of the intersex index (ISI) in Littorina littorea and the ecological risk expressed as the Potentially Affected Fraction (PAF) of species were made. The results were compared to actual ISI measurements and presence of L. littorea in the field. The PAF calculated on the basis of TBT levels for open coastal waters ranged from 4.2% to 15.3%; for harbours it ranged from 3.5% to 26.9%. Significant intersex levels were observed only in waters where the risk was calculated above 10% PAF. This study suggests that the absence of L. littorea from some harbours with high ecological risk values can be explained by high TBT concentrations. A call is made for the use of integrated approaches like weight-of-evidence (WOE) to help practitioners improve ecological risk assessment.

  6. Morphologic variations of periwinkle and profiles of periwinkle ...

    African Journals Online (AJOL)

    Periwinkles are invertebrates rich in protein and omega-3 fatty acids. These make them relished delicacies. Three hundred and fifteen (315) individual periwinkles were hand-picked from mangrove swamp river banks and intertidal zones of Twon-Brass in Bayelsa State and Abonnema town of Rivers State. Shell length and ...

  7. Microbial Flora of Partially Processed Periwinkles (Tympantotonus ...

    African Journals Online (AJOL)

    A survey of microbial flora of partially processed periwinkles (Tympanotonus fuscatus) sold in six markets in Port Harcourt was undertaken for twelve weeks. Results show that all samples of periwinkles were contaminated with Staphylococcus aureus, Bacillus sp., Escherichia coil, Staphepidermidis sp., Micrococcus sp., ...

  8. Economic Viability and Marketing Strategies of Periwinkle ...

    African Journals Online (AJOL)

    Economic Viability and Marketing Strategies of Periwinkle Tympanotonus Fuscatus in Rivers State, Nigeria. ... The results indicated that marketing strategies are enroute, through harvesters (collectors), ... EMAIL FULL TEXT EMAIL FULL TEXT

  9. Short-term effects of increased temperature and lowered pH on a temperate grazer-seaweed interaction (Littorina obtusata/Ascophyllum nodosum)

    Science.gov (United States)

    Cardoso, Patricia G.; Grilo, Tiago F.; Dionísio, Gisela; Aurélio, Maria; Lopes, Ana R.; Pereira, Ricardo; Pacheco, Mário; Rosa, Rui

    2017-10-01

    There has been a significant increase in the literature regarding the effects of warming and acidification on the marine ecosystem. To our knowledge, there is very little information on the potential effects of both combined stressors on marine grazer-seaweed interactions. Here, we evaluated, for the first time several phenotypic responses (e.g periwinkle survival, condition index, consumption rates, seaweed photosynthetic activity and oxidative stress) of the temperate periwinkle Littorina obtusata (grazer) and the brown seaweed Ascophyllum nodosum (prey) to such climate change-related variables, for 15 days. Increased temperature (22 °C, pH 8.0) elicited a significant lethal effect on the periwinkle within a short-term period (mortality rate > 90%). Acidification condition (18 °C, pH 7.6) was the one that showed lower mortality rates (≈20%), reflected by lower impact on periwinkle fitness and consumption rates. Under a scenario of increased temperature and lowered pH the antioxidant defences of L. obtusata seemed to be supressed increasing the risk of peroxidative damage. The seaweed evidenced signs of cellular damage under such conditions. These results suggest that: i) lower pH per se seems to benefit the interaction between grazer and seaweed while, ii) a combined scenario of increased temperature and lowered pH may be negative for the interaction, due to the unbalance between periwinkle mortality rates and consumption rates. But most importantly, since grazing often plays an important role on structuring natural communities, such predator-prey disturbances can elicit cascading effects on the remaining community structure and functioning of the temperate rocky-shore ecosystems.

  10. OPTIMISATION OF COMPRESSIVE STRENGTH OF PERIWINKLE ...

    African Journals Online (AJOL)

    In this paper, a regression model is developed to predict and optimise the compressive strength of periwinkle shell aggregate concrete using Scheffe's regression theory. The results obtained from the derived regression model agreed favourably with the experimental data. The model was tested for adequacy using a student ...

  11. Uptake and depuration of 131I from labelled diatoms (Skeletonema costatum) to the edible periwinkle (Littorina littorea)

    International Nuclear Information System (INIS)

    Wilson, R.C.; Vives i Batlle, J.; Watts, S.J.; McDonald, P.; Parker, T.G.

    2007-01-01

    Uptake and depuration of 131 I into winkles through consumption of the diatom Skeletonema costatum is described. The work follows on from previous studies that investigated the uptake of iodine into winkles from seawater and seaweed. Incorporation of 131 I in S. costatum from labelled seawater followed linear first-order kinetics with an uptake half-time of 0.40 days. Iodine uptake in winkles from labelled S. costatum also followed linear first-order kinetics, with a calculated equilibrium concentration (C ∞ ) of 42 Bq kg -1 and a transfer factor (TF) of 1.1 x 10 -4 with respect to labelled diatom food. This TF is lower than that observed for uptake of 131 I in winkles from labelled seaweed. For the depuration stage, a biphasic sequence with biological half-lives of 1.3 and 255 days was determined. The first phase is biokinetically important, given that winkles can lose two-thirds of their activity during that period. This study shows that, whilst winkles can obtain radioactive iodine from phytoplankton consumption, they do not retain the majority of that activity for very long. Hence, compared with other exposure pathways, such as uptake from seawater and macroalgae, incorporation from phytoplankton is a relatively minor exposure route

  12. Effect of depuration on heavy metal concentrations in periwinkle ...

    African Journals Online (AJOL)

    Tympanatonus fuscastus) was evaluated in this study. Periwinkle in depuration tanks were taken at intervals of 24, 48, 72 and 96 hours of depuration and analyzed for these heavy metals: Lead (Pb), Zinc (Zn), Chromium (Cr) and Cadmium (Cd).

  13. Temperature effect on water absorption in an improved periwinkle ...

    African Journals Online (AJOL)

    Studies have been carried out on the water absorption of the improved periwinkle reinforced cement stabilized lateritic bricks. These bricks were produced at different cement to laterite to periwinkle ratio of 1:3:1, 2:3:1, 3:3:1, 3:2:1, 3:1:1, and fired at an elevated temperature of 10000C and 11500C, respectively. From the ...

  14. optimisation of compressive strength of periwinkle shell aggregate

    African Journals Online (AJOL)

    user

    2017-01-01

    Jan 1, 2017 ... In this paper, a regression model is developed to predict and optimise the compressive strength of periwinkle shell aggregate concrete using Scheffe's regression theory. The results obtained from the derived regression model agreed favourably with the experimental data. The model was tested for ...

  15. Water Quality of Trickling Biological Periwinkle Shells Filter for ...

    African Journals Online (AJOL)

    Studies were carried on the design, efficiency and economics of trickling biological periwinkle shells filter in recirculating aquaculture systems for catfish production. The designed biofilter and other system components were constructed, assembled and commissioned for pilot catfish production. The system with the designed ...

  16. New evidence of the Littorina transgressions in the Kattegat

    DEFF Research Database (Denmark)

    Bjørnsen, Mette; Clemmensen, Lars B; Murray, Andrew S.

    2008-01-01

    Recent geomorphological and sedimentological investigation of the raised beach ridge plain on Anholt in the Kattegat Sea, Denmark, has demonstrated how these deposits, when combined with Optically Stimulated Luminescence (OSL) dating, can provide information about past changes in relative sea level....... The southwest-northeast trending plain is divided into three topographic levels, one of which has been surveyed using Ground-Penetrating Radar (GPR). Samples retrieved from the survey line indicate that the initial part of the beach ridge plain formed about 7700 years ago in response to a mid-Holocene Littorina...

  17. Morphology and properties of periwinkle shell asbestos-free brake pad

    Directory of Open Access Journals (Sweden)

    D.S. Yawas

    2016-01-01

    Full Text Available The development of asbestos-free automotive brake pad using periwinkle shell particles as frictional filler material is presented. This was with a view to exploiting the characteristics of the periwinkle shell, which is largely deposited as a waste, in replacing asbestos which has been found to be carcinogenic. Five sets of brake pads with different sieve size (710–125 μm of periwinkle shell particles with 35% resin were produced using compressive moulding. The physical, mechanical and tribological properties of the periwinkle shell particle-based brake pads were evaluated and compared with the values for the asbestos-based brake pads. The results obtained showed that compressive strength, hardness and density of the developed brake pad samples increased with decreasing the particle size of periwinkle shell from 710 to 125 μm, while the oil soak, water soak and wear rate decreased with decreasing the particle size of periwinkle shell. The results obtained at 125 μm of periwinkle shell particles compared favourably with that of commercial brake pad. The results of this research indicate that periwinkle shell particles can be effectively used as a replacement for asbestos in brake pad manufacture.

  18. Candidatus Phytoplasma malaysianum, a novel taxon associated with virescence and phyllody of Madagascar periwinkle (Catharanthus roseus)

    Science.gov (United States)

    This study addressed the taxonomic position and group classification of a phytoplasma responsible for virescence and phyllody symptoms in naturally diseased Madagascar periwinkle plants in western Malaysia. Unique regions in the 16S rRNA gene from the Malaysian periwinkle virescence (MaPV) phytopla...

  19. Preliminary data on Littorina littorea development under rearing conditions

    Directory of Open Access Journals (Sweden)

    Isabel Cunha

    2014-06-01

    Figure 1 – Data of frequency of number of eggs of L. littorea observed per egg capsule (A and mean outer diameter of egg capsules with different number of egg (B. Figure 2 – Images of Littorina littorea larvae at various days after hatching; A – eggs; B – 3 day old larvae, dorsal view; C – 3 day old larvae, lateral view view; D – 7 day old larvae, dorsal view; E – 12 day old larvae; F – 27 day old larvae. Figure 3 - Relation between shell length and age of L. littorea larvae. From hatching to day 7 and from day 15 onwards, growth curve adjust to an exponential equation. There is a stagnation of growth between day 8 and 15 coinciding with settling.

  20. The environmental requirements of Crunoecia irrorata (Curtis, 1834 (Trichoptera: Lepidostomatidae and the potential of the species for use as an indicator: an example from the Vistulian glaciation area

    Directory of Open Access Journals (Sweden)

    Anna Rychła

    2014-02-01

    Full Text Available The caddisfly Crunoecia irrorata is a wide-spread species in Europe and inhabits permanent spring areas with pristine or moderately disturbed habitat conditions. However, the pattern of its distribution on the national scale as well as detailed preferences toward water properties are still insufficiently known. To complete this knowledge we analysed at first the distribution of this species in Poland which showed that its extent involves the whole territory, however, with sparse occurrence in most regions and with large areas where the species has not been observed yet. The data compilation also showed that the species’ frequency of occurrence is highest in the central-western region of Poland. Furthermore, its frequency of occurrence decreased towards the east and the northeast. Because the highest frequency of occurrence of this species was found in central-western Poland, the spring sites in this region were used as a model area for the analysis of the hydrochemical conditions associated with the species (25 parameters. The results of the study showed that C. irrorata strongly prefers habitats with low nitrate (NO3 and chloride (Cl concentrations. In detail, a regression model showed that the probability of occurrence of C. irrorata was only 5 % at concentrations of 32 mg L-1 NO3 and 35 mg L-1 Cl. In contrast, high concentrations of heavy metals (zinc, lead, cooper, chromium, and cadmium as well as of total iron and manganese did not significantly influence the presence of this species. In conclusion, environmental assessments relating to human health and landscape health can use C. irrorata as an indicator species for biogenic and salt pollution, but the species is not a potential indicator of heavy metals in spring water. Therefore, information on the presence of C. irrorata can serve to preserve crenic ecosystems and their assemblages and can be used to prevent anthropogenic contamination of these ecosystems.

  1. Effects of Periwinkle Shell Ash on Lime-Stabilized Lateritic Soil ...

    African Journals Online (AJOL)

    ADOWIE PERE

    Keywords: atterberg limits, lateritic soil, lime stabilization, periwinkle shell ash .... specimen were prepared by carefully and completely ..... Fourth Edition. Canada: CENGAGE Learning. Holtz, RD; Kovacs, WD (1981). ... Potentials of Sugar cane.

  2. Avian Pox Discovered in the Critically Endangered Waved Albatross (Phoebastria irrorata) from the Galápagos Islands, Ecuador.

    Science.gov (United States)

    Tompkins, Emily M; Anderson, David J; Pabilonia, Kristy L; Huyvaert, Kathryn P

    2017-10-01

    The Waved Albatross (Phoebastria irrorata) is a critically endangered seabird in a rapidly shrinking population in the Galápagos Islands, Ecuador. The introduction of novel pathogens and parasites poses a threat to population persistence. Monitoring disease prevalence and guarding against the spread of such agents in endemic taxa are conservation priorities for the Galápagos, where recent increases in the prevalence of avian pox may have contributed to population declines and range contractions in other bird species. During November 2013-January 2014, we identified 14 Waved Albatross nestlings at our study site on Española Island with avian pox-like lesions and clinical signs. Other seabirds, landbirds, and adult Waved Albatrosses were apparently unaffected. Histopathology of tissue samples from five infected nestlings revealed inclusion bodies in all samples, consistent with avipoxvirus infection. We documented higher mortality (6 of 14 nestlings) in affected nestlings than in unaffected young in this small outbreak of avian pox, the first report of its kind in the world's only tropical albatross.

  3. Complete genome sequence of a divergent strain of lettuce chlorosis virus from Periwinkle in China

    Science.gov (United States)

    A novel strain of Lettuce chlorosis virus (LCV) was identified from periwinkle in China (PW) with foliar interveinal chlorosis and plant dwarfing. Complete nucleotide (nt) sequences of genomic RNA1 and RNA2 of the virus are 8,602 nt and 8,456 nt, respectively. The genomic organization of LCV-PW rese...

  4. Accumulation of platinum group elements by the marine gastropod Littorina littorea

    Energy Technology Data Exchange (ETDEWEB)

    Mulholland, Rachel [School of Geography, Earth and Environmental Sciences, University of Plymouth, Drake Circus, Plymouth PL4 8AA (United Kingdom); Turner, Andrew, E-mail: aturner@plymouth.ac.uk [School of Geography, Earth and Environmental Sciences, University of Plymouth, Drake Circus, Plymouth PL4 8AA (United Kingdom)

    2011-04-15

    The accumulation and trophic transfer of the platinum group elements (PGE): Rh, Pd and Pt; have been studied in short-term (5 day) exposures conducted in aquaria containing the marine macroalga, Ulva lactuca, and/or the grazing mollusc, Littorina littorea. Metals added to sea water (to concentrations of 20 {mu}g L{sup -1}) were taken up by U. lactuca in the order Rh, Pt > Pd and by L. littorea in the order Pd {>=} Pt {>=} Rh, with greatest metal accumulation in the latter generally occurring in the visceral complex and kidney. When fed contaminated alga, accumulation of Rh and Pd by L. littorea, relative to total available metal, increased by an order of magnitude, while accumulation of Pt was not readily detected. We conclude that the diet is the most important vector for accumulation of Rh and Pd, while accumulation of Pt appears to proceed mainly from the aqueous phase. - Research highlights: > Platinum group elements are accumulated by, Littorina littorea. > The aqueous phase and diet are important vehicles for Rh and Pd accumulation by the snail. > Grazing molluscs may serve as biomonitors of coastal PGE contamination. - Platinum group elements are accumulated by the marine snail, Littorina littorea, from both the aqueous phase and the diet.

  5. Accumulation of aqueous and dietary thallium by the marine snail, Littorina littorea

    Science.gov (United States)

    Turner, Andrew; Pilsbury, Amy

    2013-09-01

    Thallium is a highly toxic metal whose biogeochemical behaviour in the marine environment is poorly understood. The dominant species predicted in sea water (Tl+) is also chemically and biologically analogous to the potassium ion. In this study, the accumulation of Tl(I) by the littorinid snail, Littorina littorea, was examined under carefully controlled laboratory conditions for a period of five days. The snail was exposed to sea water amended with a sub-phytotoxic concentration of Tl (5 μg L-1) and to a food source (the green macroalga, Ulva lactuca) that had been pre-contaminated by Tl in sea water at the same concentration. L. littorina accumulated Tl from sea water relative to food in a ratio of about 20:1 and there were no significant differences in Tl concentrations among the different tissues analysed (head, foot, visceral mass, gonads) for each treatment. When availabilities of Tl in each vector were compared, however, it was found that only 2% of sea water Tl was accumulated compared with about 15% of dietary Tl. Uptake of Tl appears to proceed via both the gills and gut, while at the cellular level accumulation likely involves binding with biomolecules and exchange with K+ in potassium-bearing mineralised granules.

  6. TBT-gehalten en effecten bij de Gewone Alikruik (Littorina littorea) en de Gevlochten Fuikhoorn (Nassarius reticulatus) langs de Nederlandse kust in 2009

    NARCIS (Netherlands)

    Kaag, N.H.B.M.; Jol, J.; Hoek-van Nieuwenhuizen, van M.

    2009-01-01

    Sinds 2005 analyseert IMARES het voorkomen van intersex bij Gewone Alikruiken (Littorina littorea) die op vaste locaties langs de Nederlandse kust verzameld worden. Het doel van dit onderzoek is effecten van verontreiniging met TBT vast te stellen.

  7. A weight-of-evidence approach to assessing the ecological impact of organotin pollution in Dutch marine brackish waters; combining risk prognosis and field monitoring using common periwinkles (Littorina littorea)

    NARCIS (Netherlands)

    Schipper, R.; Smit, M.G.D.; Kaag, N.H.B.M.; Vethaak, A.D.

    2008-01-01

    In the present study an integrated ecological risk assessment based on multiple lines of evidence (LOEs) was evaluated in order to better assess the risk from TBT in Dutch harbours and open coastal waters. On the basis of spatial distributions of measured tributyltin (TBT) concentrations in

  8. Performance of Periwinkle Shell Ash Blended Cement Concrete Exposed to Magnesium Sulphate

    Directory of Open Access Journals (Sweden)

    Umoh A.A.

    2013-01-01

    Full Text Available The study examined the compressive strength of periwinkle shell ash (PSA blended cement concrete in magnesium sulphate medium. Specimens were prepared from designed characteristics strength of 25 MPa. The cement replacement with PSA ranged between 0 and 40% by volume. A total of 180 cube specimens were cast and cured in water. At 28 days curing, 45 specimens each were transferred into magnesium sulphate of 1%, 3%, and 5% solution, while others were continuously cured in water and tested at 62, 92, and 152 days. The results revealed a higher loss in compressive strength with the control mix, and that it increases with increased in MgSO4 concentration and exposure period, whereas, the attack on the PSA blended cement concrete was less and the least value recorded by 10% PSA content. Therefore, the study concluded that the optimum percentage replacement of cement with 10% PSA could mitigate magnesium sulphate attack.

  9. Studies on the Use of Oyster, Snail and Periwinkle Shells as Adsorbents for the Removalof Pb2+ Aqueous Solution

    Directory of Open Access Journals (Sweden)

    Stevens A. Odoemelam

    2009-01-01

    Full Text Available In view of increasing rate of lead pollution resulting from discharge of lead containing effluents by industries into the environment, this study was carried out to investigate the removal of Pb2+ from aqueous solutions by oyster, snail and periwinkle shells. The effects of contact time and concentration on adsorption, thermodynamics of sorption and distribution coefficients of the adsorbents were examined to optimize the conditions to be utilized for decontamination of effluents containing Pb2+. The study revealed that these materials are good adsorbents that can be used for the removal of Pb2+ from aqueous solution. Adsorption of Pb2+ by oyster, snail and periwinkle shells were found to conform to the classical models of Langmuir, Freundlich and Temkin adsorption isotherms. Thermodynamic consideration revealed that adsorption of Pb2+ by these materials was spontaneous and proceeded via chemical adsorption. The use of these materials for the removal of lead ion from aqueous solution is therefore advocated

  10. Antimicrobial and antioxidant activities of ethyl acetate and methanol extracts of Littorina littorea and Galatea paradoxa

    Directory of Open Access Journals (Sweden)

    Lawrence Sheringham Borquaye

    2016-12-01

    Full Text Available The aquatic environment is a vital resource for bioprospecting pharmacologically important natural products. Molluscs are known to harbour compounds with antimicrobial, antitumor and antioxidant activities. This study evaluated the antimicrobial and antioxidant properties of ethyl acetate and methanol tissue extracts of two molluscs, Littorina littorea (L. littorea and Galatea paradoxa (G. paradoxa. Agar diffusion and broth dilution assays were used to test for antimicrobial activity against nine microbes. The 1,1-diphenyl-2-picrylhydrazyl (DPPH method was used to determine antioxidant activity of the extracts. Extracts of both molluscs showed significant activity against all the bacteria strains tested but were inactive towards the fungus. The best antibacterial activity was recorded by methanol extract of L. littorea towards Pseudomonas aeruginosa. In comparison to ethyl acetate extracts, methanol extracts were more efficient in scavenging the DPPH radical. Methanol extracts of L. littorea had an IC50 of 0.37 mg/mL which was closer to that of the standard ascorbic acid drug (0.0048 mg/mL than any of the other extracts. The findings of this work indicate that the tissue extracts of L. littorea and G. paradoxa are promising sources of antimicrobial and antioxidant agents that can be utilized for pharmaceutical and nutraceutical purposes.

  11. [NADPH-diaphorase activity in digestive system of gastropod molluscs Achatina fulica and Littorina littorea].

    Science.gov (United States)

    Zaĭtseva, O V; Kuznetsova, T V; Markosova, T G

    2009-01-01

    Localization and peculiarities of NO-ergic elements were studied for he first time throughout the entire length of digestive tract of the marine gastropod mollusc Achatina fulica (Prosobranchia) and the terrestrial molusc Littorina littorea (Pulmonata) by using histochemical method of detection of NADPH-diaphorase (NADPHd). NO-ergic cells and fibers were revealed in all parts of the mollusc digestive tract beginning from pharynx. An intensive NADPHd activity was found in many intraepithelial cells of the open type and in their processes in intra- and subepithelial nerve plexuses, single subepithelial neurons, granular connective tissue cells, and numerous nerve fibers among muscle elements of he digestive tract wall as well as in nerves innervating the tract. NADPHd was also present in receptor cells of he oral area and in the central A. fulica ganglia participating in innervation of the digestive tract. The digestive tract NO-ergic system ofA. fulica has a more complex organization that that of L. littorea. In the A. fulica pharynx, stomach, and midgut, directly beneath epithelium, there is revealed a complex system of glomerular structures formed by thin NADPHd-positive nerve fibers coming from the side of epithelium. More superficially under the main groups of muscle elements, small agglomerations of NADPHd-positive neurons are seen, which could be considered as primitive, non-formed microganglia. Peculiarities of distribution and a possible functional role of NO-ergic elements in the digestive tract of molluscs are discussed as compared with other invertebrate and vertebrate animals.

  12. Morphological effects of tributyltin (TBT) in vitro on the genital system of the mesogastropoda Littorina littorea (Prosobranchia)

    Science.gov (United States)

    Deutsch, U.; Brick, M.

    1993-02-01

    This ultrastructural study investigates the pathological changes in the penial, the sperm groove and the glandular cushion epithelium in male Littorina littorea (Mesogastropoda) related to TBT (tributyltin) contamination. The results are compared with those on Ocinebrina aciculata (Neogastropoda), which shows a wide range of cell changes in the penis epithelia of male and imposex affected females. The investigation of the different penis epithelia of L. littorea revealed that the cells analysed show a low sensibility towards TBT. The cells display normal metabolism. Certain atypical structures like swelling microvilli and cristae which tend to lie parallel to the long axis in the mitochondria, were detected as pathological effects.

  13. Effects of Salicylic acid and Humic acid on Vegetative Indices of Periwinkle (Catharanthus roseusL.

    Directory of Open Access Journals (Sweden)

    E. Chamani

    2016-07-01

    Full Text Available Introduction: Vinca flower (Catharanthus roseus L. is one of the most important medicinal plants of Apocynaceae (31, 27. Tropical plant native to a height of 30 to 35 centimeters (9 and a perennial shrub which is grown in cold areas for one year (27.One of the plants in the world today as a medicinal plant used the periwinkle plant. Among the 130 indole – terpenoids alkaloids which have been identified in the plant periwinkle vinca alkaloids vincristine and vinblastin are the most important component is used to treat a variety of cancers. Including therapies that are used for a variety of cancer, chemotherapy to help Vinca alkaloids collection (including vincristine and…. Vinblastin as effective member of this category, due to the low percentage of venom and effects at very low doses, is widely used today. These materials are generally formed as inhibitors of mitotic spindle in dividing cells have been identified. Vinblastin with these structural changes in connection kinotokor - microtubules and centrosomes in a dividing cell, the mitotic spindle stop (45.Salicylic acid belongs to a group of phenolic compounds found in plants, and today is widely regarded as a hormone-like substance. These classes of compounds act as growth regulators. Humic substances are natural organic compounds that contain 50 to 90% of organic matter, peat, charcoal, rotten food and non-living organic materials are aquatic and terrestrial ecosystems (2. Materials and Methods: In this experiment, vinca F2 seeds in the mixed 4: 1 perlite and peat moss to the planting trays were sown. The seedlings at the 6-leaf stage were transfered to the main pot (pot height 30 and 25 cm diameter The pots bed soil mix consisting of 2 parts soil to one part sand and one part peat moss (v / v were used and after the establishment of seedlings in pots every two weeks with. Salicylic acid and humic acid concentrations 0 (control, 10, 100, 500 and 1000 mg were treated as a foliar spray

  14. PREPARATION AND INVESTIGATION OF THE PHOTOCATALYTIC PROPERTIES OF PERIWINKLE SHELL ASH FOR TARTRAZINE DECOLOURISATION

    Directory of Open Access Journals (Sweden)

    N.A. Amenaghawon

    2014-12-01

    Full Text Available The discharge of dye-containing effluents into the aquatic environment represents a source of aesthetic pollution with associated negative effects. Photocatalytic degradation has been identified as a suitable means of treating these effluents. In this study, the potential of a locally sourced material, periwinkle shell ash (PSA, has been explored as an effective photocatalyst for the photocatalytic decolourisation of tartrazine in aqueous solution. The efficiency of the photocatalyst was evaluated by investigating the effects of operational variables such as irradiation time, initial dye concentration and catalyst loading on the extent of decolourisation. The results show that the optimum levels of the variables were 50 minutes, 30 mg/L and 5 g/L for irradiation time, initial dye concentration and catalyst loading respectively. The pseudo first order and the Langmuir-Hinshelwood kinetic models were able to sufficiently describe the kinetics of the process. The diffusion mechanism was described by the intra-particle diffusion model while the adsorption equilibrium was described by the Langmuir isotherm equation. The results obtained indicate that PSA can be used as an effective photocatalyst for the removal of tartrazine from aqueous solution.

  15. TBT-gehalten en effecten bij de Gewone Alikruik (Littorina littorea) en de Gevlochten Fuikhoorn (Nassarius reticulatus) langs de Nederlandse kust in 2010

    NARCIS (Netherlands)

    Kaag, N.H.B.M.; Jol, J.G.; Hoek-van Nieuwenhuizen, van M.

    2012-01-01

    Sinds 2005 analyseert IMARES in opdracht van Rijkswaterstaat (RIKZ, later de Waterdienst) het voorkomen van intersex bij de Gewone Alikruik (Littorina littorea) die op vaste locaties langs de Nederlandse kust verzameld worden. Het doel van dit onderzoek is effecten van verontreiniging met

  16. Ornamental Exterior versus Therapeutic Interior of Madagascar Periwinkle (Catharanthus roseus: The Two Faces of a Versatile Herb

    Directory of Open Access Journals (Sweden)

    Naghmeh Nejat

    2015-01-01

    Full Text Available Catharanthus roseus (L. known as Madagascar periwinkle (MP is a legendary medicinal plant mostly because of possessing two invaluable antitumor terpenoid indole alkaloids (TIAs, vincristine and vinblastine. The plant has also high aesthetic value as an evergreen ornamental that yields prolific blooms of splendid colors. The plant possesses yet another unique characteristic as an amiable experimental host for the maintenance of the smallest bacteria found on earth, the phytoplasmas and spiroplasmas, and serves as a model for their study. Botanical information with respect to synonyms, vernacular names, cultivars, floral morphology, and reproduction adds to understanding of the plant while the geography and ecology of periwinkle illustrate the organism’s ubiquity. Good agronomic practices ensure generous propagation of healthy plants that serve as a source of bioactive compounds and multitudinous horticultural applications. The correlation between genetic diversity, variants, and TIA production exists. MP is afflicted with a whole range of diseases that have to be properly managed. The ethnobotanical significance of MP is exemplified by its international usage as a traditional remedy for abundant ailments and not only for cancer. TIAs are present only in micro quantities in the plant and are highly poisonous per se rendering a challenge for researchers to increase yield and reduce toxicity.

  17. Distribucion arborea de los gastropodos cerithidea montagnei (mollusca potamidae y littorina Spp. (Mollusca, Littorinidae en el manglar de Mata de Limón, Costa Rica

    Directory of Open Access Journals (Sweden)

    Édgar Suarez B

    2016-03-01

    Full Text Available En el manglar de Mata de Limón, Puntarenas, Costa Rica, se estudió la distribución y preferencia por el susbtrato arbóreo de gastrópodos C. montagnei y Littorina spp. en cuatro especies de mangle, según la cantidad de moluscos observados en cada árbol y la cantidad de árboles con presencia o ausencia de ellos, en el período de setiembre de 1982 a junio de 1983. El orden de preferencia mostrado por ambos grupos de moluscos fue: 1 Rhizophora mangle, 2 Avicennia germinans, 3Pelliciera rhizophorae y 4 Laguncularia racemosa. Se discuten las posibles razones de esta preferencia. Cerithidea montagnei presentó una mayor distribución horizontal, así como una mayor abundancia respecto de Littorina spp.

  18. Effects of tributyltin (TBT) and testosterone on the female genital system in the mesogastropod Littorina littorea (Prosobranchia)

    Science.gov (United States)

    Deutsch, U.; Fioroni, P.

    1996-03-01

    Experiments were performed with the mesogastropod Littorina littorea on Helgoland, in Roscoff, and in the laboratory in order to evaluate the reaction of the female genital system to TBT, an environmental toxicant. The snails were either injected with 50 or 100 ng tributyltin (TBT) soluted in ethanol or exposed to artificial sea water treated with 5, 50, 100, and 200 ng TBT/l, and 33 ng testosterone/l. The duration of the experiments was either four or eight weeks. None of the analysed female L. littorea showed signs of imposex. Compared to results for the control groups, the size of the female glandular complex was significantly reduced if the pre-experimental toxication was already high, as is the case in snails collected around Helgoland. TBT-related gland complex reduction occurs also in female L. littorea from other sampling sites. In addition, injection of ethanol also causes a decrease in gland size. The experimental results demonstrate that the distal female genital system responds with significantly lower sensitivity to TBT than that of other prosobranchs. This behaviour is ascribed to the lack of an androgen receptor at the ovipositor. The results further strengthen the case of the extreme rarity of imposex described for female L. littorea in natural habitats. However, strong TBT-toxication may affect L. littorea populations significantly because of increasing masculinization of the females, which reduces reproduction ability.

  19. Analysis of Metal-Binding Features of the Wild Type and Two Domain-Truncated Mutant Variants of Littorina littorea Metallothionein Reveals Its Cd-Specific Character

    Directory of Open Access Journals (Sweden)

    Òscar Palacios

    2017-07-01

    Full Text Available After the resolution of the 3D structure of the Cd9-aggregate of the Littorina littorea metallothionein (MT, we report here a detailed analysis of the metal binding capabilities of the wild type MT, LlwtMT, and of two truncated mutants lacking either the N-terminal domain, Lltr2MT, or both the N-terminal domain, plus four extra flanking residues (SSVF, Lltr1MT. The recombinant synthesis and in vitro studies of these three proteins revealed that LlwtMT forms unique M9-LlwtMT complexes with Zn(II and Cd(II, while yielding a complex mixture of heteronuclear Zn,Cu-LlwtMT species with Cu(I. As expected, the truncated mutants gave rise to unique M6-LltrMT complexes and Zn,Cu-LltrMT mixtures of lower stoichiometry with respect to LlwtMT, with the SSVF fragment having an influence on their metal binding performance. Our results also revealed a major specificity, and therefore a better metal-coordinating performance of the three proteins for Cd(II than for Zn(II, although the analysis of the Zn(II/Cd(II displacement reaction clearly demonstrates a lack of any type of cooperativity in Cd(II binding. Contrarily, the analysis of their Cu(I binding abilities revealed that every LlMT domain is prone to build Cu4-aggregates, the whole MT working by modules analogously to, as previously described, certain fungal MTs, like those of C. neoformans and T. mesenterica. It is concluded that the Littorina littorea MT is a Cd-specific protein that (beyond its extended binding capacity through an additional Cd-binding domain confers to Littorina littorea a particular adaptive advantage in its changeable marine habitat.

  20. Influence of joint application of heavy metals on level of each metal accumulated in the periwinkle Tympanotonus fuscatus (Gastropoda: Potamididae)

    International Nuclear Information System (INIS)

    Otitoloju, A.A.; Don-Pedro, K.N.

    2006-01-01

    Most laboratory assessments on toxicity and bioaccumulation of heavy metals have been concentrated on the accumulation of these metal ions when exposed singly to the test organisms. However, under the natural environmental settings, the metals are never present in isolation and may interact with each other, therefore justifying the need to study the influence of joint application of metals on accumulated levels in exposed animals. In this study, exposure of the periwinkle Tympanotonus fuscatus to sublethal concentrations (equivalent to 0.1 and 0.01 of 96 h LC 5 0) of heavy metals revealed that they were bioaccumulative varying amounts, depending on the type of metal, exposure period and concentration in the test media. while Zn and Pb ions accumulation increased steadily with exposure time, the amounts of Cu accumulated fluctuated regularly over the 30-day experimental period. The levels of Zn, Cu and Cd bioaccumulated over the 30-day experimental period were reduced by over 2-6 folds (with bioaccumulation radio values ranging from 0.15 to 0.81) when compared to concentrations of the respective metals accumulated during single bioaccumulation studies. However, Pb concentrations accumulated during the joint action studies increased nearly 2-fold (bioaccumulation ratio range 1.36 to 2.0-fold). (author) [es

  1. HETEROGENEOUS PHOTOCATALYTIC DEGRADATION OF PHENOL IN AQUEOUS SUSPENSION OF PERIWINKLE SHELL ASH CATALYST IN THE PRESENCE OF UV FROM SUNLIGHT

    Directory of Open Access Journals (Sweden)

    OSARUMWENSE, J. O.

    2015-12-01

    Full Text Available The batch photocatalytic degradation of phenol in aqueous solution wasinvestigated using periwinkle shell ash (PSA as photocatalyst. Chemical characterisation of the PSA revealed that the major oxides present were calcium oxide (CaO, silica (SiO2 and aluminium oxide (Al2O3 which accounted for 41.3, 33.2 and 9.2% of the weight of PSA characterised. The major elements in PSA were iron (19.2% and zinc (16.5%. FTIR results revealed absorption peaks of 3626.59 cm−1, 1797.58 cm−1, 1561.43 cm−1 and 1374.34 cm−1 in the infrared spectrum of PSA corresponding to O–H, C= O, C= C and C–H bonds respectively. Increasing the initial phenol concentration resulted in a decrease in the degradation efficiency of PSA. Lower catalyst loadings favoured the degradation process. Maximum degradation efficiency was obtained when the initial phenol concentration and catalyst loading were set as 50 g/L and 5 g/L respectively. The kinetics of the degradation process was well described by the pseudo first order equation while the diffusion mechanism was well represented by the intra particle diffusion model (R2>0.90. The adsorption equilibrium data fitted well to the Langmuir isotherm equation with an R2 value of 0.997.

  2. Effects of GA3, BA, Thiamine and Ascorbic Acid on Some Morphological and Biochemical Characteristics of Periwinkle (Catharanthus roseus L.

    Directory of Open Access Journals (Sweden)

    F. Baniasadi

    2016-07-01

    Full Text Available Introduction: Catharanthus roseus (L. belongs to Apocynaceae family is an important medicinal plant and also cultivated as an ornamental plant almost throughout the tropical and subtropical areas all over the world. Recently, the uses of natural substances are considered very helpful to improve plant growth and development. Application of plant growth regulators (PGRs and vitamins are reported in many horticultural crops. Ascorbic acid is the most abundant antioxidant in plant which protects plant cells. This substance affects cell differentiation and growth. Now a day it is considered as a plant growth regulator. Thiamine or vitamin B1 is water soluble and one of the B complex vitamins. This study was conducted to investigate the effect of the ascorbic acid, thiamine, BA and GA on growth and biochemical parameters of periwinkle. Materials and Methods: The experiment was perform as a completely randomized design with 5 replications at research greenhouse of Shahid Bahonar University of Kerman in 2014.The treatments used include spraying water (control, ascorbic acid 100 mg.l-1, gibberellic acid 100 mg.l-1, thiamine 100 mg.l-1, BA 200 mg. l-1 and combinations of two, three and four of them to determine the response of plants to these substances alone or in combination of them. When the seedlings become on 6-leavs stage, the first foliar spray was carried out. In other two steps was repeated with interval of 10 days. In this study, longevity of the flower, flower diameter, the number of lateral branches, branches length, fresh and dry weight, chlorophyll content and reduced sugars were measured. Chlorophyll content and reduced sugars were measured according to method of Somogy (1952 and Lichtenthder (1987, respectively. Results and Discussion: The results showed that the effect of thiamine on the number of flowers was more pronounced than other substances. The lowest number of flowers per plant was found in plants treated with gibberellic acid

  3. The Complete Plastid Genome Sequence of Madagascar Periwinkle Catharanthus roseus (L.) G. Don: Plastid Genome Evolution, Molecular Marker Identification, and Phylogenetic Implications in Asterids

    Science.gov (United States)

    Ku, Chuan; Chung, Wan-Chia; Chen, Ling-Ling; Kuo, Chih-Horng

    2013-01-01

    The Madagascar periwinkle ( Catharanthus roseus in the family Apocynaceae) is an important medicinal plant and is the source of several widely marketed chemotherapeutic drugs. It is also commonly grown for its ornamental values and, due to ease of infection and distinctiveness of symptoms, is often used as the host for studies on phytoplasmas, an important group of uncultivated plant pathogens. To gain insights into the characteristics of apocynaceous plastid genomes (plastomes), we used a reference-assisted approach to assemble the complete plastome of C . roseus , which could be applied to other C . roseus -related studies. The C . roseus plastome is the second completely sequenced plastome in the asterid order Gentianales. We performed comparative analyses with two other representative sequences in the same order, including the complete plastome of Coffea arabica (from the basal Gentianales family Rubiaceae) and the nearly complete plastome of Asclepias syriaca (Apocynaceae). The results demonstrated considerable variations in gene content and plastome organization within Apocynaceae, including the presence/absence of three essential genes (i.e., accD, clpP, and ycf1) and large size changes in non-coding regions (e.g., rps2-rpoC2 and IRb-ndhF). To find plastome markers of potential utility for Catharanthus breeding and phylogenetic analyses, we identified 41 C . roseus -specific simple sequence repeats. Furthermore, five intergenic regions with high divergence between C . roseus and three other euasterids I taxa were identified as candidate markers. To resolve the euasterids I interordinal relationships, 82 plastome genes were used for phylogenetic inference. With the addition of representatives from Apocynaceae and sampling of most other asterid orders, a sister relationship between Gentianales and Solanales is supported. PMID:23825699

  4. Induced mutation to monocotyledony in periwinkle, Catharanthus ...

    Indian Academy of Sciences (India)

    Unknown

    (i) insufficiency in endogenous kinetin may lead to monocotyledonous embryo patterning and (ii) dicotyledonous em- ... Induced-mutagenesis experiments in plants have so far .... C. roseus is a small perennial herb of family Apocyna-.

  5. Mobile Incubation in Waved Albatross (Phoebastria irrorata: Associated Hatching Failure and Artificial Mitigation

    Directory of Open Access Journals (Sweden)

    Jill A. Awkerman

    2005-12-01

    Full Text Available Waved albatrosses often relocate their eggs during incubation by placing the egg between the tarsi and shuffling forward. This behavior frequently results in eggs becoming lodged between rocks, accounting for at least 10%, and perhaps as much as 80%, of breeding failures. Because albatross populations worldwide are currently threatened, artificial means of augmenting reproductive success may be necessary to mitigate losses caused by anthropogenic effects. We characterize the frequency and extent of egg movement; test several hypotheses related to microhabitat, timing, and incubation location to explain the behavior; and investigate the utility of repositioning lodged eggs in a location in which breeding birds might resume incubation. Egg rescue increased both the likelihood of continued incubation as well as the hatching rate in our experiment, and provides an efficient, low-cost management option for this species.

  6. Exploratory study of crushed periwinkle shell as partial replacement ...

    African Journals Online (AJOL)

    The CPWS had a bulk density of 1504kg/m3, while that of the river sand was 1636kg/m3. The workability test revealed that the slump values decreased in the concrete mixture as the quantity of CPWS increased. It was also discovered that the compressive strength decreased with increased percentage of replacement of the ...

  7. comparative toxicity of petrol and kerosene to periwinkle

    African Journals Online (AJOL)

    PROF EKWUEME

    and kerosene are toxic to the environment with petrol being more toxic than the kerosene. ... automobiles, generators, heating or cooking at home, ... O. S. Edori, Department of Chemistry, Ignatius Ajuru University of Education, PMB 5047 ...

  8. Evaluation of the properties of lightweight concrete using periwinkle ...

    African Journals Online (AJOL)

    % and 100% partial replacement of PWS using water/cement (W/C) ratio of 0.55 was used. Seventy two cubes of 150 mm x 150 mm x 150 mm were casted; allowed to set for 24 hours before remolding, and were properly cured. The strength ...

  9. Comparative toxicity of petrol and kerosene to periwinkle ...

    African Journals Online (AJOL)

    The comparative toxicities of two petroleum products, petrol and kerosene were examined by exposing Tympanotonus fuscatus to acute concentrations (60, 90, 120 and 150ml/L) of these toxicants for 96 hours. The 48th hour LC50 for petrol was 177.36 ml/L, while that of kerosene was 306.16 ml/L. The 96th hour LC50 was ...

  10. Properties of Rice Husk Ash Concrete with Periwinkle Shell as ...

    African Journals Online (AJOL)

    Akorede

    1Department of Civil Engineering, Bayero University Kano, Kano State, Nigeria. 2Department of Civil Engineering, Kebbi State University of Science and Technology, Kebbi, Nigeria ... occurring clean sand, free from impurities, was used as the.

  11. The design of trickling biological periwinkle shells filter for closed ...

    African Journals Online (AJOL)

    ... and economics of biofilter in reirculating aquaculture systems using local material ... The system with the designed biofilter served as the treatment system, while the ... The selected system recirculation rate was 10 times per hour, while the ...

  12. Heavy metal concentrations in water, sediment and periwinkle ...

    African Journals Online (AJOL)

    User

    2013-05-08

    May 8, 2013 ... Sci. pp: 92-98. Wiener JG (2002). Evolution of a contaminant problem: Mercury in fresh water fish. Proceedings and summary report, USEPA/625/R-02/005. World Health Organisation (WHO) (1994). Assessing human health risk of chemicals, derivation of guidance values for health based exposure limits.

  13. comparative toxicity of petrol and kerosene to periwinkle

    African Journals Online (AJOL)

    PROF EKWUEME

    effects of oil pollution in the aquatic environment deals only on the effects of whole crude or the refined fractions. ... aquatic ecosystem and thereby cause great damages to the aquatic environment in a number of ways. ..... Monitoring of water quality and wastewater quality. Blacksbury, USA. Beynon, L. R and Cowell, E. B., ...

  14. Oil spillage and its impact on the edible mangrove periwinkle ...

    African Journals Online (AJOL)

    Oil spills are a regular occurrence in the oil industry in Nigeria, a process that results in the release of excess hydrocarbons into the environment, negatively impacting plant and animal species. Laboratory and field experiments were conducted on refined oil impacted and fire ravaged mangrove ecosystem to determine the ...

  15. temperature effect on water absorption in an improved periwinkle ...

    African Journals Online (AJOL)

    Nwokem et al.

    Adding a reinforcement into a laterite soil as a building material is one of the ... meet building standard. Omubo-Pepple et al .... Journal of Issues in Professional Teachers Education. 3: 151-160. ... Journal of Applied Physics, 70, 1160-1165. 3.

  16. Experimental Evaluation of Seaweeds as a Vector for Microplastics into Marine Food Webs.

    Science.gov (United States)

    Gutow, Lars; Eckerlebe, Antonia; Giménez, Luis; Saborowski, Reinhard

    2016-01-19

    The ingestion of microplastics has been shown for a great variety of marine organisms. However, benthic marine mesoherbivores such as the common periwinkle Littorina littorea have been largely disregarded in studies about the effects of microplastics on the marine biota, probably because the pathway for microplastics to this functional group of organisms was not obvious. In laboratory experiments we showed that the seaweed Fucus vesiculosus retains suspended microplastics on its surface. The numbers of microplastics that adhered to the algae correlated with the concentrations of suspended particles in the water. In choice feeding assays L. littorea did not distinguish between algae with adherent microplastics and clean algae without microplastics, indicating that the snails do not recognize solid nonfood particles in the submillimeter size range as deleterious. In periwinkles that were feeding on contaminated algae, microplastics were found in the stomach and in the gut. However, no microplastics were found in the midgut gland, which is the principle digestive organ of gastropods. Microplastics in the fecal pellets of the periwinkles indicate that the particles do not accumulate rapidly inside the animals but are mostly released with the feces. Our results provide the first evidence that seaweeds may represent an efficient pathway for microplastics from the water to marine benthic herbivores.

  17. Acidification and warming affect both a calcifying predator and prey, but not their interaction

    DEFF Research Database (Denmark)

    Landes, Anja; Zimmer, Martin

    2012-01-01

    Both ocean warming and acidification have been demonstrated to affect the growth, performance and reproductive success of calcifying invertebrates. However, relatively little is known regarding how such environmental change may affect interspecific interactions. We separately treated green crabs...... to environmental change. Acidification negatively affected the closer-muscle length of the crusher chela and correspondingly the claw-strength increment in C. maenas. The effects of warming and/or acidification on L. littorea were less consistent but indicated weaker shells in response to acidification...... Carcinus maenas and periwinkles Littorina littorea under conditions that mimicked either ambient conditions (control) or warming and acidification, both separately and in combination, for 5 mo. After 5 mo, the predators, prey and predator-prey interactions were screened for changes in response...

  18. Intersex in Littorina littorea and DNA damage in Mytilus edulis as indicators of harbour polllution

    DEFF Research Database (Denmark)

    Rank, Jette

    2009-01-01

    of exposure to genotoxic chemicals, and the intersex index (ISI) observed in snails was an indicator of exposure to butyltin (BT) compounds. Biota and sediments were analysed for heavy metals (Cd, Cu, Pb and Zn), butyltin compounds (TBT, DBT and MBT), nine PCB congeners and 19 PAH compounds. The biological...

  19. Ionising radiation effect on the luminescence emission of inorganic and biogenic calcium carbonates

    Science.gov (United States)

    Boronat, C.; Correcher, V.; Virgos, M. D.; Garcia-Guinea, J.

    2017-06-01

    As known, the luminescence emission of mineral phases could be potentially employed for dosimetric purposes in the case of radiological terrorism or radiation accident where conventional monitoring is not available. In this sense, this paper reports on the thermo- (TL) and cathodoluminescence (CL) emission of both biogenic (common periwinkle - littorina littorera - shell made of calcite 90% and aragonite 10%) and inorganic (aragonite 100%) Ca-rich carbonates previously characterized by X-ray diffraction and Raman spectroscopy. Whereas the aragonite sample displays the main CL waveband peaked in the red region (linked to point defects), the more intense emission obtained from the common periwinkle shell appears at higher energies (mainly associated with structural defects). The UV-blue TL emission of the samples, regardless of the origin, displays (i) an acceptable ionizing radiation sensitivity, (ii) linear dose response in the range of interest (up to 8 Gy), (iii) reasonable stability of the TL signal after 700 h of storage with an initial decay of ca. 88% for the mineral sample and 60% for the biogenic sample and maintaining the stability from 150 h onwards. (iv) The tests of thermal stability of the TL emission performed in the range of 180-320 °C confirm a continuum in the trap system.

  20. Grazing effects of the periwinkle Echinolittorina peruviana at a central Peruvian high rocky intertidal

    Science.gov (United States)

    Hidalgo, Fernando J.; Firstater, Fausto N.; Fanjul, Eugenia; Bazterrica, M. Cielo; Lomovasky, Betina J.; Tarazona, Juan; Iribarne, Oscar O.

    2008-03-01

    Echinolittorina peruviana is the most common gastropod in the high intertidal zone of Peru, representing more than 80% of the individuals present at that zone. Experimental removal of snails was used to evaluate their effects on (a) abundance of epilithic biofilm, (b) barnacle recruitment, and (c) abundance of macroalgae under “normal” conditions of the El Niño Southern Oscillation (ENSO). Experiments were carried out from October 2005 to April 2007 at two intertidal levels of a semi-protected rocky shore of central Peru. Results demonstrated that E. peruviana is able to control biofilm abundance and barnacle recruitment at both heights investigated, with marked effects in the lower zone. Erect macroalgae ( Ulva spp. and Gelidium spp.) were less affected by grazing; but negative effects were observed on macroalgal crusts. Season and physical stress seem to play a more important role in the abundance of macroalgae in the high intertidal. Our results are similar to those reported elsewhere for high shore littorinids and represent baseline data to understand how the role of intertidal consumers will vary under the cold (La Niña) and warm (El Niño) phases of ENSO on these shores.

  1. Effects of Periwinkle Shell Ash on Lime-Stabilized Lateritic Soil ...

    African Journals Online (AJOL)

    Journal of Applied Sciences and Environmental Management. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 21, No 6 (2017) >. Log in or Register to get access to full text downloads.

  2. Influence of Black Mangrove Expansion on Salt Marsh Food Web Dynamics in Coastal Louisiana

    Science.gov (United States)

    Powell, C.; Baustian, M. M.; Polito, M. J.

    2017-12-01

    The range of black mangroves (Avicennia germinans) is projected to expand in the northern Gulf of Mexico due to reduced winter freeze events and an increased rate of droughts. The colonization of mangroves in salt marshes alters habitat structure and creates a novel basal carbon source for consumers. This addition may modify trophic linkages and the structure of estuarine food webs. To understand the implications of mangrove expansion on food web dynamics of traditional Spartina alterniflora marshes, two sites in coastal Louisiana with three habitat types, marsh-dominated, mangrove-dominated, and a transition or mix of the two, were studied. Community composition of juvenile nekton was sampled using fyke nets, minnow traps, and suction sampling and analyzed for abundance and diversity. Primary carbon sources (emergent vegetation, phytoplankton, macroalgae, benthic microalgae, submerged aquatic vegetation, and soil organic matter) and consumers ((blue crabs (Callinectes sapidus), brown shrimp (Farfantepenaeus aztecus), grass shrimp (Palaemonetes spp.), Gulf killifish (Fundulus grandis), periwinkle snails (Littoraria irrorata), eastern oysters (Crassostrea virginica), and southern ribbed mussels (Geukensia granosissima)) collected at each habitat type were measured using stable isotope analysis (δ13C, δ15N, δ34S) to identify trophic level, basal carbon sources, and assess how mangrove carbon is incorporated into salt marsh food webs. While data analysis is ongoing, preliminary results indicate that basal carbon sources supporting some marsh consumers (e.g., periwinkle snails) shift between habitat types, while others remain static (e.g., grass shrimp). This research will further develop our understanding of how climate induced shifts in vegetation influences valued marsh-dependent consumers in the estuarine ecosystems of northern Gulf of Mexico.

  3. [Distribution of acetylcholinesterase activity in the digestive system of the gastropod molluscs Littorina littorea and Achatina fulica].

    Science.gov (United States)

    Zaĭtseva, O V; Kuznetsova, T V

    2008-01-01

    With the use of the histochemical procedure for the demonstration of acetylcholinesterase (AchE) activity, the distribution cholinergic regulatory elements was studied in the esophagus, the pharynx, the stomach, the liver (the digestive gland) and the intestine in sea and terrestrial gastropod molluscs that differed in their general organization level, lifestyle, habitat and feeding type. In both molluscs, all the parts of the digestive tract contained the significant amount of intraepithelial AchE-positive cells of the open type, single subepithelial neurons and the nervous fibers localized among the muscle cells of the wall of the organs. The basal processes of the AchE-positive intraepithelial cells were shown to form the intraepithelial nerve plexus and to pass under the epithelium. The peculiarities and common principles in the distribution of the nervous elements detected, their possible function and the regulatory role in the digestion in gastropod molluscs and other animals are discussed.

  4. Ionising radiation effect on the luminescence emission of inorganic and biogenic calcium carbonates

    Energy Technology Data Exchange (ETDEWEB)

    Boronat, C. [CIEMAT, Av. Complutense 40, Madrid 28040 (Spain); Correcher, V., E-mail: v.correcher@ciemat.es [CIEMAT, Av. Complutense 40, Madrid 28040 (Spain); Virgos, M.D. [CIEMAT, Av. Complutense 40, Madrid 28040 (Spain); Garcia-Guinea, J. [CSIC, Museo Nacional Ciencias Naturales, José Gutiérrez Abascal 2, Madrid 28006 (Spain)

    2017-06-15

    Highlights: • Aragonite and biogenic Ca-carbonates could be used as a TL dosimeters. • TL can be employed for retrospective dosimetry purposes. • Calcium carbonates show an acceptable ionizing radiation sensitivity. • The stability of the radiation–induced TL remains, at least, till 700 h. - Abstract: As known, the luminescence emission of mineral phases could be potentially employed for dosimetric purposes in the case of radiological terrorism or radiation accident where conventional monitoring is not available. In this sense, this paper reports on the thermo- (TL) and cathodoluminescence (CL) emission of both biogenic (common periwinklelittorina littorera – shell made of calcite 90% and aragonite 10%) and inorganic (aragonite 100%) Ca-rich carbonates previously characterized by X-ray diffraction and Raman spectroscopy. Whereas the aragonite sample displays the main CL waveband peaked in the red region (linked to point defects), the more intense emission obtained from the common periwinkle shell appears at higher energies (mainly associated with structural defects). The UV-blue TL emission of the samples, regardless of the origin, displays (i) an acceptable ionizing radiation sensitivity, (ii) linear dose response in the range of interest (up to 8 Gy), (iii) reasonable stability of the TL signal after 700 h of storage with an initial decay of ca. 88% for the mineral sample and 60% for the biogenic sample and maintaining the stability from 150 h onwards. (iv) The tests of thermal stability of the TL emission performed in the range of 180–320 °C confirm a continuum in the trap system.

  5. Ionising radiation effect on the luminescence emission of inorganic and biogenic calcium carbonates

    International Nuclear Information System (INIS)

    Boronat, C.; Correcher, V.; Virgos, M.D.; Garcia-Guinea, J.

    2017-01-01

    Highlights: • Aragonite and biogenic Ca-carbonates could be used as a TL dosimeters. • TL can be employed for retrospective dosimetry purposes. • Calcium carbonates show an acceptable ionizing radiation sensitivity. • The stability of the radiation–induced TL remains, at least, till 700 h. - Abstract: As known, the luminescence emission of mineral phases could be potentially employed for dosimetric purposes in the case of radiological terrorism or radiation accident where conventional monitoring is not available. In this sense, this paper reports on the thermo- (TL) and cathodoluminescence (CL) emission of both biogenic (common periwinklelittorina littorera – shell made of calcite 90% and aragonite 10%) and inorganic (aragonite 100%) Ca-rich carbonates previously characterized by X-ray diffraction and Raman spectroscopy. Whereas the aragonite sample displays the main CL waveband peaked in the red region (linked to point defects), the more intense emission obtained from the common periwinkle shell appears at higher energies (mainly associated with structural defects). The UV-blue TL emission of the samples, regardless of the origin, displays (i) an acceptable ionizing radiation sensitivity, (ii) linear dose response in the range of interest (up to 8 Gy), (iii) reasonable stability of the TL signal after 700 h of storage with an initial decay of ca. 88% for the mineral sample and 60% for the biogenic sample and maintaining the stability from 150 h onwards. (iv) The tests of thermal stability of the TL emission performed in the range of 180–320 °C confirm a continuum in the trap system.

  6. Effects of microplastics on European flat oysters, Ostrea edulis and their associated benthic communities.

    Science.gov (United States)

    Green, Dannielle Senga

    2016-09-01

    Plastic pollution is recognised as an emerging threat to aquatic ecosystems, with microplastics now the most abundant type of marine debris. Health effects caused by microplastics have been demonstrated at the species level, but impacts on ecological communities remain unknown. In this study, impacts of microplastics on the health and biological functioning of European flat oysters (Ostrea edulis) and on the structure of associated macrofaunal assemblages were assessed in an outdoor mesocosm experiment using intact sediment cores. Biodegradable and conventional microplastics were added at low (0.8 μg L(-1)) and high (80 μg L(-1)) doses in the water column repeatedly for 60 days. Effects on the oysters were minimal, but benthic assemblage structures differed and species richness and the total number of organisms were ∼1.2 and 1.5 times greater in control mesocosms than in those exposed to high doses of microplastics. Notably, abundances of juvenile Littorina sp. (periwinkles) and Idotea balthica (an isopod) were ∼2 and 8 times greater in controls than in mesocosms with the high dose of either type of microplastic. In addition, the biomass of Scrobicularia plana (peppery furrow shell clam) was ∼1.5 times greater in controls than in mesocosms with the high dose of microplastics. This work indicates that repeated exposure to high concentrations of microplastics could alter assemblages in an important marine habitat by reducing the abundance of benthic fauna. Copyright © 2016 Elsevier Ltd. All rights reserved.

  7. Accumulation of Sellafield-derived radiocarbon ((14)C) in Irish Sea and West of Scotland intertidal shells and sediments.

    Science.gov (United States)

    Tierney, Kieran M; Muir, Graham K P; Cook, Gordon T; MacKinnon, Gillian; Howe, John A; Heymans, Johanna J; Xu, Sheng

    2016-01-01

    The nuclear energy industry produces radioactive waste at various stages of the fuel cycle. In the United Kingdom, spent fuel is reprocessed at the Sellafield facility in Cumbria on the North West coast of England. Waste generated at the site comprises a wide range of radionuclides including radiocarbon ((14)C) which is disposed of in various forms including highly soluble inorganic carbon within the low level liquid radioactive effluent, via pipelines into the Irish Sea. This (14)C is rapidly incorporated into the dissolved inorganic carbon (DIC) reservoir and marine calcifying organisms, e.g. molluscs, readily utilise DIC for shell formation. This study investigated a number of sites located in Irish Sea and West of Scotland intertidal zones. Results indicate (14)C enrichment above ambient background levels in shell material at least as far as Port Appin, 265 km north of Sellafield. Of the commonly found species (blue mussel (Mytilus edulis), common cockle (Cerastoderma edule) and common periwinkle (Littorina littorea)), mussels were found to be the most highly enriched in (14)C due to the surface environment they inhabit and their feeding behaviour. Whole mussel shell activities appear to have been decreasing in response to reduced discharge activities since the early 2000s but in contrast, there is evidence of continuing enrichment of the carbonate sediment component due to in-situ shell erosion, as well as indications of particle transport of fine (14)C-enriched material close to Sellafield. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  8. Consumer trait variation influences tritrophic interactions in salt marsh communities.

    Science.gov (United States)

    Hughes, Anne Randall; Hanley, Torrance C; Orozco, Nohelia P; Zerebecki, Robyn A

    2015-07-01

    The importance of intraspecific variation has emerged as a key question in community ecology, helping to bridge the gap between ecology and evolution. Although much of this work has focused on plant species, recent syntheses have highlighted the prevalence and potential importance of morphological, behavioral, and life history variation within animals for ecological and evolutionary processes. Many small-bodied consumers live on the plant that they consume, often resulting in host plant-associated trait variation within and across consumer species. Given the central position of consumer species within tritrophic food webs, such consumer trait variation may play a particularly important role in mediating trophic dynamics, including trophic cascades. In this study, we used a series of field surveys and laboratory experiments to document intraspecific trait variation in a key consumer species, the marsh periwinkle Littoraria irrorata, based on its host plant species (Spartina alterniflora or Juncus roemerianus) in a mixed species assemblage. We then conducted a 12-week mesocosm experiment to examine the effects of Littoraria trait variation on plant community structure and dynamics in a tritrophic salt marsh food web. Littoraria from different host plant species varied across a suite of morphological and behavioral traits. These consumer trait differences interacted with plant community composition and predator presence to affect overall plant stem height, as well as differentially alter the density and biomass of the two key plant species in this system. Whether due to genetic differences or phenotypic plasticity, trait differences between consumer types had significant ecological consequences for the tritrophic marsh food web over seasonal time scales. By altering the cascading effects of the top predator on plant community structure and dynamics, consumer differences may generate a feedback over longer time scales, which in turn influences the degree of trait

  9. A laboratory and field study of 210Po depuration by edible winkles (Littorina littorea L.) from the Cumbrian coast (north-eastern Irish Sea)

    International Nuclear Information System (INIS)

    Swift, D.J.; Smith, D.L.; Allington, D.J.; Winpenny, K.

    1995-01-01

    Edible winkles from Saltom Bay, Cumbria (north-eastern Irish Sea) had flesh 210 Po concentrations in excess of 200 Bq kg -1 (wet). This came from liquid waste discharged under authorisation from a chemical plant producing phosphoric acid. This labelling of the winkles under natural conditions was exploited to determine the 210 Po depuration rate and biological half-time. Winkles transferred to Lowestoft and depurated in flowing seawater had biological half-times ranging from 82 to 119 days depending on temperature. After the chemical plant was shut, changes in Saltom Bay winkle flesh contents of 210 Po, 210 Pb and cadmium were followed by monthly samples. The biological half-time in the environment for the decrease in 210 Po after the plant closed was estimated at about 92 days. (author)

  10. Accumulation of Monoterpenoid Indole Alkaloids in Periwinkle Seedlings ("Catharanthus roseus") as a Model for the Study of Plant-Environment Interactions

    Science.gov (United States)

    Miranda-Ham, Maria de Lourdes; Islas-Flores, Ignacio; Vazquez-Flota, Felipe

    2007-01-01

    Alkaloids are part of the chemical arsenal designed to protect plants against an adverse environment. Therefore, their synthesis and accumulation are frequently induced in response to certain environmental conditions and are mediated by chemical signals, which are formed as the first responses to the external stimulus. A set of experiments using…

  11. Accumulation of Sellafield-derived radiocarbon ("1"4C) in Irish Sea and West of Scotland intertidal shells and sediments

    International Nuclear Information System (INIS)

    Tierney, Kieran M.; Muir, Graham K.P.; Cook, Gordon T.; MacKinnon, Gillian; Howe, John A.; Heymans, Johanna J.; Xu, Sheng

    2016-01-01

    The nuclear energy industry produces radioactive waste at various stages of the fuel cycle. In the United Kingdom, spent fuel is reprocessed at the Sellafield facility in Cumbria on the North West coast of England. Waste generated at the site comprises a wide range of radionuclides including radiocarbon ("1"4C) which is disposed of in various forms including highly soluble inorganic carbon within the low level liquid radioactive effluent, via pipelines into the Irish Sea. This "1"4C is rapidly incorporated into the dissolved inorganic carbon (DIC) reservoir and marine calcifying organisms, e.g. molluscs, readily utilise DIC for shell formation. This study investigated a number of sites located in Irish Sea and West of Scotland intertidal zones. Results indicate "1"4C enrichment above ambient background levels in shell material at least as far as Port Appin, 265 km north of Sellafield. Of the commonly found species (blue mussel (Mytilus edulis), common cockle (Cerastoderma edule) and common periwinkle (Littorina littorea)), mussels were found to be the most highly enriched in "1"4C due to the surface environment they inhabit and their feeding behaviour. Whole mussel shell activities appear to have been decreasing in response to reduced discharge activities since the early 2000s but in contrast, there is evidence of continuing enrichment of the carbonate sediment component due to in-situ shell erosion, as well as indications of particle transport of fine "1"4C-enriched material close to Sellafield. - Highlights: • We measure "1"4C activity in shells and sediment at sites on the UK west coast. • Mussel shell activity varies in response to average "1"4C discharges from Sellafield. • Shell activities reflect species feeding habits and ecological niche. • NE Irish Sea inorganic sediment activity will gradually increase. • Increases in sediment activity will occur at remote sites on the Scottish west coast.

  12. Evaluation of the Properties of Lightweight Concrete Using ...

    African Journals Online (AJOL)

    ADOWIE PERE

    strength characteristics of each cube were evaluated using Compressive Testing machine at the curing .... properties of periwinkle shell ash burnt in a furnace at 300°C for 2 .... Exploratory. Study f Periwinkle Shells As Coarse Aggregate In.

  13. Microbiological quality of raw and processed farm reared ...

    African Journals Online (AJOL)

    African Journal of Food, Agriculture, Nutrition and Development ... farm reared periwinkles from brackish water earthen pond Buguma, Nigeria ... the enumeration of indicator organisms and other pathogens as well as their total counts. ... The boiled shell-on periwinkle sample had the highest level of microbial growth.

  14. The genus Rhododendron L. in Indochina and Siam

    NARCIS (Netherlands)

    Sleumer, H.

    1958-01-01

    In the course of my recent revision of the genus Rhododendron in Malaysia it has become evident, that the subsect. Irrorata, regarded as purely South Eastern Asiatic up to now, is also represented in the Malay Peninsula and Sumatra, whilst the subsect. Euvireya, outside of its large Malaysian area,

  15. assessment of some mechanical properties and microstructure

    African Journals Online (AJOL)

    user

    PARTICULATE PERIWINKLE SHELL-ALUMINIUM 6063 METAL MATRIX. COMPOSITE .... elements between sodium (Na, Z=11) and uranium (U, Z. =92). PPS is found to ... interact with the grain refining ingredient in PPS and this resulted to ...

  16. Heavy Metal Analyses and Nutritional Composition of Raw and ...

    African Journals Online (AJOL)

    PROF HORSFALL

    KEYWORDS: Nutritional composition, heavy metals, fresh water fishes, marine water fishes, lagoons. Introduction. Fish is an .... the flame and 90% passed out as waste. The flame ..... metals in surface water, sediments, fish and periwinkles of ...

  17. A checklist of malacofauna of the Vellar Estuarine Mangroves, India

    Directory of Open Access Journals (Sweden)

    K. Kesavan

    2009-07-01

    Full Text Available A survey conducted to know the diversity of malacofauna in Vellar estuarine mangroves (southeast coast of India. In this study, 13 species of molluscs (10 species of gastropods - Melampus ceylonicus, Cerithidea cingulata, Cassidula nucleus, Pythia plicata, Neritina (Dostia violacea, Littorina scabra, Littorina melanostoma, Ellobium aurisjudae, C. obtusa T. telescopium and Assiminea nitida and 3 species of bivalves - Perna viridis, Crassostrea madrasensis and Modiolus metcalfei were recorded. M. pulchella, C. obtusa, L. scabra and N. violacea were found arboreal. T. telescopium, C. cingulata and E. aurisjudae were found crawling on the intertidal mud.

  18. TBT-gehalten en effecten bij de Gewone Alikruik, de Gevlochten Fuikhoorn en de Purperslak langs de Nederlandse kust in 2012

    NARCIS (Netherlands)

    Hoek-van Nieuwenhuizen, van M.; Jol, J.G.; Kaag, N.H.B.M.

    2013-01-01

    Sinds 2005 analyseert IMARES in opdracht van Rijkswaterstaat (RIKZ, later de Waterdienst) het voorkomen van intersex bij de Gewone Alikruiken (Littorina littorea) die op vaste locaties langs de Nederlandse kust verzameld worden. Het doel van dit onderzoek is effecten van verontreiniging met

  19. TBT - gehalten en effecten bij de Gewone alikruik, de Gevlochten Fuikhoorn en de Purperslak langs de Nederlandse kust in 2011

    NARCIS (Netherlands)

    Hoek-van Nieuwenhuizen, van M.; Jol, J.G.

    2011-01-01

    Sinds 2005 analyseert IMARES in opdracht van Rijkswaterstaat het voorkomen van intersex bij de Gewone Alikruiken (Littorina littorea) die op vaste locaties langs de Nederlandse kust verzameld worden. Het doel van dit onderzoek is effecten van verontreiniging met organotinverbindingen vast te

  20. Browse Title Index

    African Journals Online (AJOL)

    Items 351 - 400 of 1329 ... Vol 10, No 2 (2006), Distribution of Lead and total Hydrocarbon in Tissues of Periwinkles (Tympanotonus fuscatus and Pachymelania aurita) in the upper Bonny River, Nigeria, Abstract PDF. TJK Ideriah, SA Braide, AO Briggs. Vol 20, No 3 (2016), Distribution of phthalate esters in underground water ...

  1. Lablab purpureus

    Indian Academy of Sciences (India)

    and for whole dry grains and split dhal, used in various food preparations and snacks ...... of the domestication syndrome in common bean. Crop Sci. 36, ... flower color in periwinkle: orange-red corolla and white eye. J. Hered. 93, 55–57.

  2. Sharing information and collections on phytoplasmas: from QBOL to QBANK

    DEFF Research Database (Denmark)

    Bertaccini, Assunta; Paltrinieri, Samanta; Makarova, Olga

    2011-01-01

    A total of 154 phytoplasma strains from 15 ribosomal groups were employed for barcode sequences production. Besides strains in periwinkle, 36 strains in natural infected plants such as napier grass, grapevine, plum, jujube, apple, pear, spartium, pine tree, hibiscus and erigeron were employed...

  3. Journal of Genetics | Indian Academy of Sciences

    Indian Academy of Sciences (India)

    Home; Journals; Journal of Genetics. Sushil Kumar. Articles written in Journal of Genetics. Volume 79 Issue 3 2000 pp 97-104. Induced mutation to monocotyledony in periwinkle, Catharanthus roseus, and suppression of mutant phenotype by kinetin · Shashi Pandey Rai Sushil Kumar · More Details Abstract Fulltext PDF.

  4. NJP VOLUME 41 NO 4

    African Journals Online (AJOL)

    PROF. EZECHUKWU

    2014-06-17

    Jun 17, 2014 ... intolerance and constipation had acquired hypothyroid- ism. In children .... rich foods such as periwinkle, oysters and water in this region, there is a ... fore salt iodization to prevent the excessive exposure of the thyroid gland to ...

  5. Environmental Assessment for Establishment of an Off-Highway Vehicle (OHV) Program at Arnold Air Force Base, Tennessee

    Science.gov (United States)

    2010-05-01

    ha/apense Johnsongrass High Vinca minor Periwinkle High Wisteria sinensis Wisteria High Pinus spp. Pine spp. High Poncirus trifoliata Trifoliate... drought are occurring around the time of exposure (Larkin, 1996). Studies have documented hearing loss caused by the noise of dune buggies, dirt bikes

  6. Browse Title Index

    African Journals Online (AJOL)

    Items 251 - 300 of 781 ... Vol 27, No 1 (2000), Effects of population density on the growth and ... fish meal with periwinkle flesh on the performance of broiler chickens, Abstract ... Vol 38, No 2 (2011), Effects of skip a day (SAD) feeding regime ... Vol 28, No 1 (2001), Egg production curve of Rhode Island Red chickens, Abstract.

  7. Untitled

    African Journals Online (AJOL)

    ABSTRACT: The total hydrocarbon (THC) content ofthree marine organisms; Periwinkles. (Pachyelina aurira), mussels (Mylz'rus edulis) and ... petroleum industries include,depletion of marine organisms, destruction of algae and some ... and mussels (M. edzzlis) are preferred pollution biomonitors because apart from being ...

  8. Sublethal Effects of Diesel on Total Protein Levels and Cholesterol ...

    African Journals Online (AJOL)

    Michael Horsfall

    were handpicked at the Eagle Cement area of the New Calabar River and subjected to different levels ... groups when compared to the control in both the muscle and the viscera of the periwinkle. ... In Nigeria, oil industry operations are both offshore and onshore. ... This acts as a means of assessing the hazard or potential ...

  9. Assessment of some mechanical properties and microstructure of ...

    African Journals Online (AJOL)

    AlMMC and compares the properties of the composites and those of the aluminium 6063 (AA6063) alloy. Periwinkle shells were milled to particle sizes of 75μm and 150μm and used to produce PPS-AlMMC at 1,5,10 and 15wt% filler loadings ...

  10. Physiological responses of suspension cultures of Catharanthus roseus to aluminum: changes in polyamines and inorganic ions

    Science.gov (United States)

    Xinhua Zhou; Rakesh Minocha; Subhash C. Minocha

    1995-01-01

    The effects of aluminum (Al) treatment on polyamines were studied using suspension cultures of Madagascar periwinkle [Catharanthus roseus (L.) G. Don]. The addition of A1 (0.2, 0.5, 1.0 mM) to the suspension cultures caused a significant increase in putrescine within 24h only in freshly transferred cells. By contrast, Al treatment reduced putrescine...

  11. Evaluation of Concentrations and Human Health Risk of Cu, Zn, Fe ...

    African Journals Online (AJOL)

    The estimated daily intake of the metals in the periwinkles was all higher than their provisional tolerable daily and weekly intakes set by regulatory bodies. The non-carcinogenic risks (THQ and HI) of the individual and combined risk of the metals were within the limit of 1 set by USEPA, indicating no health risk at the moment ...

  12. Herklots 1857

    African Journals Online (AJOL)

    STORAGESEVER

    2009-04-20

    Apr 20, 2009 ... the Lagos metropolitan area (WES, 1997) and their ... environmental control settings of crude oil spillages in ... impact and risk assessment now facing ecotoxicologists .... produced the biological response (LC50 or median response levels ..... mixtures of heavy metals against the mangrove periwinkle.

  13. Journal of Pharmaceutical and Allied Sciences - Vol 14, No 1 (2017)

    African Journals Online (AJOL)

    Physico-chemical properties of a modified biomaterial from Tympanotonus fuscata (periwinkle) shell powder considered as pharmaceutical excipient · EMAIL FULL TEXT EMAIL FULL TEXT DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT. K.C Ugoeze, A Chukwu, 2417-2429 ...

  14. The use of agricultural waste materials for concrete making ...

    African Journals Online (AJOL)

    This paper presents laterite as fine aggregate and agricultural waste materials such as periwinkle shell, (PS) and palm kernel shell (PKS) as coarse aggregate for making concrete. Saturated surface dry (SSD) bulk density and compressive cube strength tests of concrete made from these were carried at the concrete age of ...

  15. The endophyte Curtobacterium flaccumfaciens reduces symptoms caused by Xylella fastidiosa in Catharanthus roseus.

    Science.gov (United States)

    Lacava, Paulo Teixeira; Li, Wenbin; Araújo, Welington Luiz; Azevedo, João Lúcio; Hartung, John Stephen

    2007-10-01

    Citrus variegated chlorosis (CVC) is a disease of the sweet orange [Citrus sinensis (L.)], which is caused by Xylella fastidiosa subsp. pauca, a phytopathogenic bacterium that has been shown to infect all sweet orange cultivars. Sweet orange trees have been occasionally observed to be infected by Xylella fastidiosa without evidencing severe disease symptoms, whereas other trees in the same grove may exhibit severe disease symptoms. The principal endophytic bacterial species isolated from such CVC-asymptomatic citrus plants is Curtobacterium flaccumfaciens. The Madagascar periwinkle [Citrus sinensis (L.)] is a model plant which has been used to study X. fastidiosa in greenhouse environments. In order to characterize the interactions of X. fastidiosa and C. flaccumfaciens, periwinkle plants were inoculated separately with C. flaccumfaciens, X. fastidiosa, and both bacteria together. The number of flowers produced by the plants, the heights of the plants, and the exhibited disease symptoms were evaluated. PCR-primers for C. flaccumfaciens were designed in order to verify the presence of this endophytic bacterium in plant tissue, and to complement an existing assay for X. fastidiosa. These primers were capable of detecting C. flaccumfaciens in the periwinkle in the presence of X. fastidiosa. X. fastidiosa induced stunting and reduced the number of flowers produced by the periwinkle. When C. flaccumfaciens was inoculated together with X. fastidiosa, no stunting was observed. The number of flowers produced by our doubly- inoculated plants was an intermediate between the number produced by the plants inoculated with either of the bacteria separately. Our data indicate that C. flaccumfaciens interacted with X. fastidiosa in C. roseus, and reduced the severity of the disease symptoms induced by X. fastidiosa. Periwinkle is considered to be an excellent experimental system by which the interaction of C. flaccumfaciens and other endophytic bacteria with X. fastidiosa can be

  16. Micropropagation and maintenance of phytoplasmas in tissue culture.

    Science.gov (United States)

    Bertaccini, Assunta; Paltrinieri, Samanta; Martini, Marta; Tedeschi, Mara; Contaldo, Nicoletta

    2013-01-01

    Maintenance of phytoplasma strains in tissue culture is achievable for all strains transmitted to periwinkle (Catharanthus roseus), and also for other naturally infected plant host species. Shoots of 1-3 cm length are grown in a solid medium containing Murashige and Skoog (MS) micro- and macroelements and 0.12 mg/L benzylaminopurine. The continued presence of phytoplasmas in infected shoots of periwinkle that have been maintained in micropropagation for up to 20 years can be shown by diagnostic methods such as nested PCR tests using the 16S rDNA gene (see Chapters 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25,and 26 for phytoplasma diagnostic methods).

  17. Environmental radiation monitoring data for Point Lepreau Generating Station, 1987. Annual publication

    Energy Technology Data Exchange (ETDEWEB)

    Sutherland, J K

    1988-01-01

    Annual report presenting a compilation of the 1987 environmental radiation monitoring program data from samples collected around the Point Lepreau Nuclear Generating Station (PLNGS) and at reference stations remote from PLNGS. About 1,800 analyses were made on 1,300 samples to monitor environmental radiation, including air filters, airborne water vapour, sea water, well water, milk, beach sediments, clams, fish, lobster, dulse, crabs, scallops and periwinkles. Background radiation is measured by thermoluminescence dosimetry.

  18. Removing chromium and lead metals using phytoremediation technique

    Directory of Open Access Journals (Sweden)

    Al-Anbari Riyad

    2018-01-01

    Full Text Available Phytoremediation technique uses plants parts to remove, extract, and absorb heavy or toxic matter from soil and water. In the present study, Catharanthusroseus (Periwinkle and Nerium Oleander (Oleander were used for removing Chromium (Cr and Lead (Pb metals. These plant species were seeded in polyethylene pots containing 8kg of soil. Each pot was irrigated with wastewater for four months (May, June, July and August and accumulation of the considered metals was analyzed after every month for leaf, stem and root by using Atomic Absorption Spectrophotometer (AAS. This experimental work was carried out in the laboratories of Water Desalination Researches Unit - Building and Construction Engineering Department and Environmental Research Centre at the University of Technology in Baghdad City, Iraq. The concentration of Cr was found to be increased with time. High Cr concentration, 20.34 mg/kg, was recorded at August in leaf of Periwinkle and 19.61 mg/kg in root of Oleander in case of using 100% wastewater (WW. While, for Pb, the maximum concentration, 22 mg/kg, was recorded in June in leaf of Periwinkle and 19.5 mg/kg in steam of Oleander. Accordingly, Oleander has the maximum removal efficiency.

  19. Proliferation and ajmalicine biosynthesis of Catharanthus roseus (L). G. Don adventitious roots in self-built temporary immersion system

    Science.gov (United States)

    Phuc, Vo Thanh; Trung, Nguyen Minh; Thien, Huynh Tri; Tien, Le Thi Thuy

    2017-09-01

    Periwinkle (Catharanthus roseus (L.) G. Don) is a medicinal plant containing about 130 types of alkaloids that have important pharmacological effects. Ajmalicine in periwinkle root is an antihypertensive drug used in treatment of high blood pressure. Adventitious roots obtained from periwinkle leaves of in vitro shoots grew well in quarter-strength MS medium supplemented with 0.3 mg/l IBA and 20 g/l sucrose. Dark condition was more suitable for root growth than light. However, callus formation also took place in addition to the growth of adventitious roots. Temporary immersion system was applied in the culture of adventitious roots in order to reduce the callus growth rate formed in shake flask cultures. The highest growth index of roots was achieved using the system with 5-min immersion every 45 min (1.676 ± 0.041). The roots cultured in this system grew well without callus formation. Ajmalicine content was highest in the roots cultured with 5-min immersion every 180 min (950 μg/g dry weight).

  20. Marine ecoregion and Deepwater Horizon oil spill affect recruitment and population structure of a salt marsh snail

    Science.gov (United States)

    Pennings, Steven C.; Zengel, Scott; Oehrig, Jacob; Alber, Merryl; Bishop, T. Dale; Deis, Donald R.; Devlin, Donna; Hughes, A. Randall; Hutchens, John J.; Kiehn, Whitney M.; McFarlin, Caroline R.; Montague, Clay L.; Powers, Sean P.; Proffitt, C. Edward; Rutherford, Nicolle; Stagg, Camille L.; Walters, Keith

    2016-01-01

    Marine species with planktonic larvae often have high spatial and temporal variation in recruitment that leads to subsequent variation in the ecology of benthic adults. Using a combination of published and unpublished data, we compared the population structure of the salt marsh snail, Littoraria irrorata, between the South Atlantic Bight and the Gulf Coast of the United States to infer geographic differences in recruitment and to test the hypothesis that the Deepwater Horizon oil spill led to widespread recruitment failure of L. irrorata in Louisiana in 2010. Size-frequency distributions in both ecoregions were bimodal, with troughs in the distributions consistent with a transition from sub-adults to adults at ~13 mm in shell length as reported in the literature; however, adult snails reached larger sizes in the Gulf Coast. The ratio of sub-adults to adults was 1.5–2 times greater in the South Atlantic Bight than the Gulf Coast, consistent with higher recruitment rates in the South Atlantic Bight. Higher recruitment rates in the South Atlantic Bight could contribute to higher snail densities and reduced adult growth in this region. The ratio of sub-adults to adults in Louisiana was lower in 2011 than in previous years, and began to recover in 2012–2014, consistent with widespread recruitment failure in 2010, when large expanses of spilled oil were present in coastal waters. Our results reveal an important difference in the ecology of a key salt marsh invertebrate between the two ecoregions, and also suggest that the Deepwater Horizon oil spill may have caused widespread recruitment failure in this species and perhaps others with similar planktonic larval stages.

  1. Bacteriohopanepolyols record stratification, nitrogen fixation and other biogeochemical perturbations in Holocene sediments of the central Baltic Sea

    Directory of Open Access Journals (Sweden)

    M. Blumenberg

    2013-04-01

    Full Text Available The Baltic Sea, one of the world's largest brackish-marine basins, established after deglaciation of Scandinavia about 17 000 to 15 000 yr ago. In the changeable history of the Baltic Sea, the initial freshwater system was connected to the North Sea about 8000 yr ago and the modern brackish-marine setting (Littorina Sea was established. Today, a relatively stable stratification has developed in the water column of the deep basins due to salinity differences. Stratification is only occasionally interrupted by mixing events, and it controls nutrient availability and growth of specifically adapted microorganisms and algae. We studied bacteriohopanepolyols (BHPs, lipids of specific bacterial groups, in a sediment core from the central Baltic Sea (Gotland Deep and found considerable differences between the distinct stages of the Baltic Sea's history. Some individual BHP structures indicate contributions from as yet unknown redoxcline-specific bacteria (bacteriohopanetetrol isomer, methanotrophic bacteria (35-aminobacteriohopanetetrol, cyanobacteria (bacteriohopanetetrol cyclitol ether isomer and from soil bacteria (adenosylhopane through allochthonous input after the Littorina transgression, whereas the origin of other BHPs in the core has still to be identified. Notably high BHP abundances were observed in the deposits of the brackish-marine Littorina phase, particularly in laminated sediment layers. Because these sediments record periods of stable water column stratification, bacteria specifically adapted to these conditions may account for the high portions of BHPs. An additional and/or accompanying source may be nitrogen-fixing (cyanobacteria, which is indicated by a positive correlation of BHP abundances with Corg and δ15N.

  2. Mercury in marine organisms of the Tay region

    Energy Technology Data Exchange (ETDEWEB)

    Jones, A M; Jones, Y; Stewart, W D.P.

    1972-07-21

    The problem of mercury pollution in the Tay region of the United Kingdom is discussed with emphasis on mercury concentration within marine algae and invertebrates. High levels of Hg were found in Broughty Ferry algae while there was no detectable mercury in any of the samples collected from north of Arbroath. Most was found in the thallose algae, Ulva lactuca and Porphyra umbilicalis, and in Ceramium rubrum. In studies carried out on molluscs, high levels were found in the lamellibranch, Mytilus edulis and in the gastropods Littorina littoralis and Nucella lapillus. 12 references, 3 tables.

  3. THE STATUS OF MOLLUSK DIVERSITY AND PHYSICAL SETTING OF THE MANGROVE ZONES IN CATANDUANES ISLAND, LUZON, PHILIPPINES

    Directory of Open Access Journals (Sweden)

    JIMMY T. MASAGCA

    2010-09-01

    Full Text Available The status of mollusk diversity and physical setting of mangrove areas in Catanduanes island, Luzon (Philippines are described. A total of 57 species of mollusks, consisting of 27 gastropods and 30 bivalves were recorded in the island. Registering higher values of species diversity indices (Margalef and species richness (Menhinick are the prosobranch, Terebralia sulcata; corbiculid bivalve, Geloina coaxans; potamidiids, Cerithidea cingulata and Cerithidea rhizophorarum; and two other species of the genus Littorina (Littorinopsis. Using the physiographic model, majority of the mangrove areas under study follow the composite river and wave-dominated setting with some few areas having the wave-dominated, tide-dominated allochthonous setting.

  4. Assessment of PAHs levels in some fish and seafood from different coastal waters in the Niger Delta

    OpenAIRE

    Nwaichi, E.O.; Ntorgbo, S.A.

    2016-01-01

    Levels of sixteen polycyclic aromatic hydrocarbons (PAHs) in 30 edible tissues of selected frequently-consumed fish and seafood collected from three coastal waters of Niger Delta, namely, Sime, Kporghor and Iko were investigated in 2014. Gas chromatographic analysis were employed for PAHs determination. Observed mean PAHs levels in the samples ranged from below detection limit (BD) of analytical instrument to 22.400 ± 0.050 μg kg−1 wet wt. in Littorina littorea, BD to 87.400 ± 0.030 μg kg−1 w...

  5. Global opvarmning neutraliserer effekten af parasitisme på strandsnegles konsumption af makroalger

    DEFF Research Database (Denmark)

    Larsen, Martin H.; Mouritsen, Kim Nørgaard

    Det er veldokumenteret, at parasitter kan påvirke værternes adfærd, overlevelse, reproduktion, fysiologi og evolution. Disse parasit-vært interaktioner kan føre til radikale ændringer af naturlige samfunds struktur og diversitet. Eksperimenter har eksempelvis vist, at trematoder indirekte kan ændre...... strukturen af makroalgesamfund ved at reducere konsumptionsraten hos den herbivore strandsnegl Littorina littorea. Det er endvidere vist, at produktionen af trematode-larver (cercarier) i sneglens fordøjelseskanal og gonade kompleks øges kraftigt når vandtemperaturen stiger. Man kan derfor forvente...

  6. Environmental radiation monitoring data for Point Lepreau Generating Station, 1990. Annual publication

    Energy Technology Data Exchange (ETDEWEB)

    Sutherland, J K

    1991-01-01

    Annual report presenting a compilation of the 1990 environmental radiation monitoring program data from samples collected around the Point Lepreau Nuclear Generating Station (PLNGS) and at reference stations remote from PLNGS. About 1,500 analyses were made on 1,100 samples to monitor environmental radiation, including air particulates, airborne water vapour, carbon dioxide in air, sea water, well water, milk, beach sediments, clams, fish, lobster, dulse, crabs, scallops, periwinkles, sea plants and lichen. Background radiation is measured by thermoluminescence dosimetry. Radon is not assessed.

  7. Heavy metal accumulation in Littoraria scabra along polluted and pristine mangrove areas of Tanzania

    Energy Technology Data Exchange (ETDEWEB)

    Wolf, H. de [Ecophysiology, Biochemistry and Toxicology Group, University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp (Belgium)], E-mail: hans.dewolf@ua.ac.be; Rashid, R. [Ecophysiology, Biochemistry and Toxicology Group, University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp (Belgium)

    2008-04-15

    The periwinkle Littoraria scabra was collected at polluted and pristine mangrove sites along the Tanzanian coastline, including Msimbazi, Mbweni (i.e. Dar es Salaam) and Kisakasaka, Nyamanzi and Maruhubi (i.e. Zanzibar). Periwinkles were morphologically characterized, sexed and their heavy metal content was determined using ICP-MS. Analysis revealed that L. scabra from polluted areas contained higher soft tissue heavy metal levels, were significantly smaller and weighed less compared to their conspecifics from the unpolluted mangroves. The current morphological observations may be explained in terms of growth and/or mortality rate differences between the polluted and non-polluted sites. Although a variety of stressors may account for these adverse morphological patterns, our data suggest a close relationship with the soft tissue heavy metal content. Compared to soft tissue heavy metal levels that were measured in L. scabra along the same area in 1998, most metals, except for arsenic, chromium and iron have decreased dramatically. - Anthropogenic activities result in heavy metal accumulation and adverse morphological effects in the mangrove gastropod Littoraria scabra.

  8. Effect of applied synthetic auxin on root growth in plantlet propagation by cuttage and tissue culture; Sashiki to soshiki baiyo ni okeru gosei auxin rui no shiyo koka

    Energy Technology Data Exchange (ETDEWEB)

    Shoji, K; Yoshihara, T [Central Research Institute of Electric Power Industry, Tokyo (Japan)

    1996-12-01

    The effect of synthetic plant hormone 4-C1-IAA and TFIBA on root growth in plantlet propagation was clarified by the cuttage and the issue culture of strawberry seedling production. A periwinkle, vine, and azalea are the effect of 4-C1-IAA on root growth, and a promotion effect was recognized for rooting and root elongation. The concentration of 4-C1-IAA in which the growth promotion effect of a root most appears varies depending on the species of a plant. The concentration of a periwinkle was 20 ppm, and that of an azalea was 2000 ppm. The growth promotion effect of a root in 4-C1-IAA and TFIBA was compared with IBA for an azalea. The result showed that 4-C1-IAA is the same in the effect as IBA and that TFIBA is higher than for IBA. The growth of a vine`s terminal bud was promoted by the effect of TFIBA on root growth, and the callus occurring when IBA was treated was not formed. The rooting of a strawberry was promoted by the effect of TFIBA on root growth. The combined use of TFIBA and BA promotes the growth of a side bud and forms a multi-bud plant. However, rooting was inhibited. The callus caused by the effect of BA on root growth could be suppressed through the combined use with TFIBA. 6 refs., 7 figs., 2 tabs.

  9. Heavy metal accumulation in Littoraria scabra along polluted and pristine mangrove areas of Tanzania

    International Nuclear Information System (INIS)

    Wolf, H. de; Rashid, R.

    2008-01-01

    The periwinkle Littoraria scabra was collected at polluted and pristine mangrove sites along the Tanzanian coastline, including Msimbazi, Mbweni (i.e. Dar es Salaam) and Kisakasaka, Nyamanzi and Maruhubi (i.e. Zanzibar). Periwinkles were morphologically characterized, sexed and their heavy metal content was determined using ICP-MS. Analysis revealed that L. scabra from polluted areas contained higher soft tissue heavy metal levels, were significantly smaller and weighed less compared to their conspecifics from the unpolluted mangroves. The current morphological observations may be explained in terms of growth and/or mortality rate differences between the polluted and non-polluted sites. Although a variety of stressors may account for these adverse morphological patterns, our data suggest a close relationship with the soft tissue heavy metal content. Compared to soft tissue heavy metal levels that were measured in L. scabra along the same area in 1998, most metals, except for arsenic, chromium and iron have decreased dramatically. - Anthropogenic activities result in heavy metal accumulation and adverse morphological effects in the mangrove gastropod Littoraria scabra

  10. Submerged terrestrial landscapes in the Baltic Sea: Evidence from multiproxy analyses of sediment cores from Fehmarnbelt

    Science.gov (United States)

    Enters, Dirk; Wolters, Steffen; Blume, Katharina; Segschneider, Martin; Lücke, Andreas; Theuerkauf, Martin; Hübener, Thomas

    2016-04-01

    Five sediment cores were taken from the southern part of the Fehmarn Belt (Baltic Sea) in the context of an environmental impact study for the intended fixed traverse between Germany and Denmark. The lithologies of the 8m long cores reveal dramatic changes in sedimentary environments which reflect the early Holocene history of the southern Baltic Sea. A succession of terrestrial, semiterrestrial and limnic facies from glacial sediments to peat, lacustrine/estuarine deposits and finally marine sediments document the interplay of eustatic sea level rise and isostatic rebound, which finally lead to the establishment of marine conditions during the Littorina transgression. An age control of the observed changes was established by dating over 50 C-14 samples of different fractions. During the Lateglacial minerogenic varves with thicknesses of several centimeters verify the existence of a proglacial lake in the Fehmarnbelt. Peat development started around 11.250 cal. BP and terminated ca. 10.600 cal. BP which is roughly contemporaneous with the end of the Yoldia Phase in the central Baltic Sea. The oldest peat layers consist of undecomposed sedges and reed. Woody remains of willows appear not before 10.700 cal BP and indicate a stagnant or slowly decreasing water table. This semi-terrestrial phase is followed by a shallow inland lake which existed until the Littorina transgression around 8.300 cal. BP. Initially the lacustrine sediments exhibit high C/N ratios, low low δ13Corg values and contain numerous wood fragments as well as other botanical macro remains. This indicates shallow conditions close to the lake shore. Later, the occurrence of planktonic diatom species such as Aulacoseira ambigua suggest greater water depths. We did not find any indications of the often postulated catastrophic outburst of the Ancylus Lake via Fehmarnbelt and the Great Belt into the North Sea. Likewise, XRF scanning does not show conspicuous peaks in Ti or K which would have been

  11. Shell biofilm-associated nitrous oxide production in marine molluscs

    DEFF Research Database (Denmark)

    Heisterkamp, I.M.; Schramm, Andreas; Larsen, Lone Heimann

    2013-01-01

    Emission of the greenhouse gas nitrous oxide (N2O) from freshwater and terrestrial invertebrates has exclusively been ascribed to N2O production by ingested denitrifying bacteria in the anoxic gut of the animals. Our study of marine molluscs now shows that also microbial biofilms on shell surfaces...... are important sites of N2O production. The shell biofilms of Mytilus edulis, Littorina littorea and Hinia reticulata contributed 18-94% to the total animal-associated N2O emission. Nitrification and denitrification were equally important sources of N2O in shell biofilms as revealed by 15N-stable isotope...... mollusc species. Ammonium excretion by the animals was found to be sufficient to sustain N2O production in the shell biofilm. Apparently, the animals provide a nutrient-enriched microenvironment that stimulates growth and N2O production of the shell biofilm. This animal-induced stimulation...

  12. Amoco Cadiz oil spill

    Energy Technology Data Exchange (ETDEWEB)

    O' Sullivan, A J

    1978-05-01

    This report gives a preliminary account of the events surrounding the wreck of the Amoco Cadiz on the Brittany coast in March, which caused the most massive oil pollution on record. The sequence of events is outlined. Also reported are details of clean-up of beaches as well as appearance and biological effects of oil. Further studies which will continue for years include: population dynamics (species of Littorina); feeding, reproduction, settlement of Spirorbis sp; surveillance of echinoderm and crustacean populations; changes in growth and development of species of red algae; changes in concentrations of bacteria, meiofauna, chlorophyll and organic material. There are indications of problems likely to arise in: sheltered areas (sediments, salt marsh vegetation); sandy shores; upper shore vegetation (higher plants, lichens); algae (temporary loss of algal cover); intertidal macrofauna; seabirds (mortality); economy (fishing, tourism, seaweed used for fertilizer).

  13. Changes in the selection differential exerted on a marine snail during the ontogeny of a predatory shore crab.

    Science.gov (United States)

    Pakes, D; Boulding, E G

    2010-08-01

    Empirical estimates of selection gradients caused by predators are common, yet no one has quantified how these estimates vary with predator ontogeny. We used logistic regression to investigate how selection on gastropod shell thickness changed with predator size. Only small and medium purple shore crabs (Hemigrapsus nudus) exerted a linear selection gradient for increased shell-thickness within a single population of the intertidal snail (Littorina subrotundata). The shape of the fitness function for shell thickness was confirmed to be linear for small and medium crabs but was humped for large male crabs, suggesting no directional selection. A second experiment using two prey species to amplify shell thickness differences established that the selection differential on adult snails decreased linearly as crab size increased. We observed differences in size distribution and sex ratios among three natural shore crab populations that may cause spatial and temporal variation in predator-mediated selection on local snail populations.

  14. The Holocene Great Belt connection to the southern Kattegat, Scandinavia

    DEFF Research Database (Denmark)

    Bendixen, Carina; Jensen, Jørn Bo; Boldreel, Lars Ole

    2017-01-01

    Late- and postglacial geological evolution of the southern Kattegat connection to the Great Belt was investigated from high-resolution seismic data and radiocarbon-dated sediment cores in order to elucidate the Ancylus Lake drainage/Littorina Sea transgression. It was found that glacial deposits...... form the acoustic basement and are covered by Lateglacial (LG) marine sediments and postglacial (PG; Holocene) material. The LG deposits form a highstand systems tract, whereas the PG deposits cover a full depositional sequence, consisting of a lowstand systems tract (PG I), transgressive systems tract...... (PG II; subdivided into three parasequences) and finally a highstand systems tract (PG III). PG I sand deposits (11.7–10.8 cal. ka BP) are found in a major western channel and in a secondary eastern channel. PG II (10.8–9.8 cal. ka BP) consists of estuarine and coastal deposits linked to an estuary...

  15. The composition of the ground water in bedrock in the precambrian shield areas of Finland and other countries

    International Nuclear Information System (INIS)

    Hyyppae, J.

    1986-11-01

    The main properties of the composition of the ground water contained in the Precambrian bedrock of Finland are presented on the basis of the results of analyses of some 1750 water samples taken from bored wells and a few mines. They show that, with a few exceptions, the waters of bored wells are bicarbonate waters, in which the average total amount of dissolved substances diminishes according to their geographical location as one moves from the coastal areas toward estern and northern Finland. The influence of the mineral composition of the bedrock appears most distinctly in the rapakivi areas, where the average fluoride content of the ground water varies between 1.5 and 2.0 mg/l and is thus ten times the corresponding content prevailing in areas characterized by other types of rocks. Ground waters containing from 439 to 18.000 mg/l of chloride have also been met with in Finnish bedrock and the location of the sampling site of 38 samples is given together with the general nature of their chemical composition as well as the results of the determinations of the stable (δ ''2H, δ ''1''8O, δ ''3''4S, δ ''1''3C) and radioactive (''3H, ''1''4C) isotopes of a number of samples. The saline waters are mostly located in the region covered 6000-7500 years ago by the Littorina Sea. On the other hand, the isotopic composition of many saline waters corresponds to that of rainwater fallen during climatic conditions colder than the present. The most saline waters have been met with deep down in mines and deep boreholes, also, for example, far from the region covered by the Littorina Sea. The saline waters contained in Finnish bedrock usually release gas, which in some cases consists mainly of nitrogen but in some places includes significant amounts of methane. In addition, helium is one of the constituents

  16. Early Holocene estuary development of the Hesselø Bay area, southern Kattegat, Denmark and its implication for Ancylus Lake drainage

    Science.gov (United States)

    Bendixen, Carina; Boldreel, Lars Ole; Jensen, Jørn Bo; Bennike, Ole; Hübscher, Christian; Clausen, Ole Rønø

    2017-12-01

    High-resolution shallow seismic data, sediment core information, radiocarbon dating and sequence stratigraphy have been used to interpret the late glacial to early Holocene geological evolution of Hesselø Bay in the southern Kattegat, Denmark. A reconstruction of the early Holocene coastal environment and a description of coastal processes associated with a river outlet into the bay are presented. Weichselian glacial deposits form the lowermost interpreted unit, covered by late glacial (LG) and postglacial (PG, Holocene) sediments. A funnel-shaped estuary existed at the mouth of channels in the period 10.3-9.2 cal. ka BP; the channels drained water from south to north. The early PG is characterised by estuarine and coastal deposits. The early Holocene bars that developed in the estuary are preserved as morphological features on the present-day seabed, possibly as a result of rapid relative sea-level rise. The estuary existed simultaneously with the occurrence and drainage of the Ancylus Lake. The drainage of this lake occurred through the Dana River (palaeo-Great Belt channel) into the southern Kattegat and then into the study area. The level of the Ancylus Lake in the Baltic Sea region dropped significantly at about 10.2 cal. ka BP at the same time as the estuary developed in the Kattegat region. One outcome of the present study is an enhanced understanding of the Ancylus Lake drainage path. No evidence of major erosion is seen, which indicates non-catastrophic continuous water flow from the south without major drainage events of the Ancylus Lake to the southern Kattegat. During the Littorina transgression, coastal estuarine conditions characterized the Hesselø Bay area where elongated ridges formed a bar system. As the Littorina transgression continued, back-stepping of the bar system and coastline occurred. When the transgression breached the Great Belt threshold, flooding caused major erosion throughout the study area.

  17. Effects of simulated oil exposure on two intertidal macrozoo benthos: Tympanotonus fuscata (L.) and Uca tangeri (Eydoux, 1935) in a tropical estuarine ecosystem.

    Science.gov (United States)

    Ewa-Oboho, I O; Abby-Kalio, N J

    1994-08-01

    The impacts of simulated Nigerian light crude oil on mud flat periwinkles, Tympanotonus fuscata (L.), and fiddler crabs, Uca tangeri (Eydoux, 1935) was examined through field experiments conducted in the Bonny estuary of the Niger Delta (southern Nigeria). The purpose was to assess the fate and effects of a known quantity of the Nigerian light crude oil on this environment. Drastic changes in the densities of T. fuscata and U. tangeri observed immediately after spills was attributed to the effects of the oil. A large increase in Uca biomass occurred in the affected area. Salinity and temperature in the study area showed little fluctuations throughout the survey. Sediment characteristics were similar for all sites (stations). Grain-size analysis revealed that sediments at the study area were 70% silt. Migration of oil via tidal percolation was observed as much as 11 cm beneath the sediment surface.

  18. Differentiation of mycoplasmalike organisms (MLOs) in European fruit trees by PCR using specific primers derived from the sequence of a chromosomal fragment of the apple proliferation MLO.

    Science.gov (United States)

    Jarausch, W; Saillard, C; Dosba, F; Bové, J M

    1994-01-01

    A 1.8-kb chromosomal DNA fragment of the mycoplasmalike organism (MLO) associated with apple proliferation was sequenced. Three putative open reading frames were observed on this fragment. The protein encoded by open reading frame 2 shows significant homologies with bacterial nitroreductases. From the nucleotide sequence four primer pairs for PCR were chosen to specifically amplify DNA from MLOs associated with European diseases of fruit trees. Primer pairs specific for (i) Malus-affecting MLOs, (ii) Malus- and Prunus-affecting MLOs, and (iii) Malus-, Prunus-, and Pyrus-affecting MLOs were obtained. Restriction enzyme analysis of the amplification products revealed restriction fragment length polymorphisms between Malus-, Prunus, and Pyrus-affecting MLOs as well as between different isolates of the apple proliferation MLO. No amplification with either primer pair could be obtained with DNA from 12 different MLOs experimentally maintained in periwinkle. Images PMID:7916180

  19. Transcriptome analysis of the phytobacterium Xylella fastidiosa growing under xylem-based chemical conditions.

    Science.gov (United States)

    Ciraulo, Maristela Boaceff; Santos, Daiene Souza; Rodrigues, Ana Claudia de Freitas Oliveira; de Oliveira, Marcus Vinícius; Rodrigues, Tiago; de Oliveira, Regina Costa; Nunes, Luiz R

    2010-01-01

    Xylella fastidiosa is a xylem-limited bacterium responsible for important plant diseases, like citrus-variegated chlorosis (CVC) and grapevine Pierce's disease (PD). Interestingly, in vitro growth of X. fastidiosa in chemically defined media that resemble xylem fluid has been achieved, allowing studies of metabolic processes used by xylem-dwelling bacteria to thrive in such nutrient-poor conditions. Thus, we performed microarray hybridizations to compare transcriptomes of X. fastidiosa cells grown in 3G10-R, a medium that resembles grape sap, and in Periwinkle Wilt (PW), the complex medium traditionally used to cultivate X. fastidiosa. We identified 299 transcripts modulated in response to growth in these media. Some 3G10R-overexpressed genes have been shown to be upregulated in cells directly isolated from infected plants and may be involved in plant colonization, virulence and environmental competition. In contrast, cells cultivated in PW show a metabolic switch associated with increased aerobic respiration and enhanced bacterial growth rates.

  20. Recovery: The untold story of Valdez spill

    International Nuclear Information System (INIS)

    Clark, R.

    1991-01-01

    The worst fears about the effect of the oil spill in Prince William Sound happily have proved to be unfounded, and the shore environment is recovering rapidly, reports Clark. Visiting the area in both the spring and fall of 1990, he found that the beaches already displayed an abundance of recolonized marine life. Young barnacles, mussels, and rockweeds had settled on the rocks, and periwinkles were laying eggs under stones at the waterline. While remnants of weathered oil were still evident among some of the rocks and sediment on shore, clark says, this oil does not appear to be either toxic or harmful. Sea otters and seabirds, which suffered heavy losses from the spill, have the capacity for rapid recovery, he notes. Also encouraging, he adds, is the fact that record catches of both herring and pink salmon occurred in the area in 1990

  1. Effects of microplastics on sessile invertebrates in the eastern coast of Thailand: An approach to coastal zone conservation.

    Science.gov (United States)

    Thushari, Gajahin Gamage Nadeeka; Senevirathna, Jayan Duminda Mahesh; Yakupitiyage, Amararatne; Chavanich, Suchana

    2017-11-15

    This study assessed the microplastic contamination of 3 most abundant sessile and intertidal invertebrates (Rock Oyster: Saccostrea forskalii, Striped Barnacle: Balanus amphitrite, Periwinkle: Littoraria sp.) in 3 beaches of the eastern coasts of Thailand. The results showed a significant accumulation of microplastics in the invertebrates at rates of 0.2-0.6 counts/g indicating higher pollution levels along the coastline. Filter feeding organisms showed comparatively higher accumulation rates of microplastics. Thus, contaminated bivalves pose potential health risks for seafood consumers. The plastic pollutant prevalence in sessile and intertidal communities was corresponded with pollution characteristics of contaminated beach habitats where they live. Thus, bivalves, gastropods and barnacles can be used as indicators for contamination of microplastics in the areas. This study also demonstrated the need for controlling plastic pollution in Thai coastal areas. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  2. Methodologies for estimating toxicity of shoreline cleaning agents in the field

    International Nuclear Information System (INIS)

    Clayton, J.R.Jr.; Stransky, B.C.; Schwartz, M.J.; Snyder, B.J.; Lees, D.C.; Michel, J.; Reilly, T.J.

    1996-01-01

    Four methodologies that could be used in a portable kit to estimate quantitative and qualitative information regarding the toxicity of oil spill cleaning agents, were evaluated. Onshore cleaning agents (SCAs) are meant to enhance the removal of treated oil from shoreline surfaces, and should not increase adverse impacts to organisms in a treated area. Tests, therefore, should be performed with resident organisms likely to be impacted during the use of SCAs. The four methodologies were Microtox T M, fertilization success for echinoderm eggs, byssal thread attachment in mussels, and righting and water-escaping ability in periwinkle snails. Site specific variations in physical and chemical properties of the oil and SCAs were considered. Results were provided, showing all combinations of oils and SCAs. Evaluation showed that all four methodologies provided sufficient information to assist a user in deciding whether or not the use of an SCA was warranted. 33 refs., 7 tabs., 11 figs

  3. Prophage-mediated dynamics of 'Candidatus Liberibacter asiaticus' populations, the destructive bacterial pathogens of citrus huanglongbing.

    Directory of Open Access Journals (Sweden)

    Lijuan Zhou

    Full Text Available Prophages are highly dynamic components in the bacterial genome and play an important role in intraspecies variations. There are at least two prophages in the chromosomes of Candidatus Liberibacter asiaticus' (Las Floridian isolates. Las is both unculturable and the most prevalent species of Liberibacter pathogens that cause huanglongbing (HLB, a worldwide destructive disease of citrus. In this study, seven new prophage variants resulting from two hyper-variable regions were identified by screening clone libraries of infected citrus, periwinkle and psyllids. Among them, Types A and B share highly conserved sequences and localize within the two prophages, FP1 and FP2, respectively. Although Types B and C were abundant in all three libraries, Type A was much more abundant in the libraries from the Las-infected psyllids than from the Las-infected plants, and Type D was only identified in libraries from the infected host plants but not from the infected psyllids. Sequence analysis of these variants revealed that the variations may result from recombination and rearrangement events. Conventional PCR results using type-specific molecular markers indicated that A, B, C and D are the four most abundant types in Las-infected citrus and periwinkle. However, only three types, A, B and C are abundant in Las-infected psyllids. Typing results for Las-infected citrus field samples indicated that mixed populations of Las bacteria present in Floridian isolates, but only the Type D population was correlated with the blotchy mottle symptom. Extended cloning and sequencing of the Type D region revealed a third prophage/phage in the Las genome, which may derive from the recombination of FP1 and FP2. Dramatic variations in these prophage regions were also found among the global Las isolates. These results are the first to demonstrate the prophage/phage-mediated dynamics of Las populations in plant and insect hosts, and their correlation with insect transmission and

  4. Prophage-mediated dynamics of 'Candidatus Liberibacter asiaticus' populations, the destructive bacterial pathogens of citrus huanglongbing.

    Science.gov (United States)

    Zhou, Lijuan; Powell, Charles A; Li, Wenbin; Irey, Mike; Duan, Yongping

    2013-01-01

    Prophages are highly dynamic components in the bacterial genome and play an important role in intraspecies variations. There are at least two prophages in the chromosomes of Candidatus Liberibacter asiaticus' (Las) Floridian isolates. Las is both unculturable and the most prevalent species of Liberibacter pathogens that cause huanglongbing (HLB), a worldwide destructive disease of citrus. In this study, seven new prophage variants resulting from two hyper-variable regions were identified by screening clone libraries of infected citrus, periwinkle and psyllids. Among them, Types A and B share highly conserved sequences and localize within the two prophages, FP1 and FP2, respectively. Although Types B and C were abundant in all three libraries, Type A was much more abundant in the libraries from the Las-infected psyllids than from the Las-infected plants, and Type D was only identified in libraries from the infected host plants but not from the infected psyllids. Sequence analysis of these variants revealed that the variations may result from recombination and rearrangement events. Conventional PCR results using type-specific molecular markers indicated that A, B, C and D are the four most abundant types in Las-infected citrus and periwinkle. However, only three types, A, B and C are abundant in Las-infected psyllids. Typing results for Las-infected citrus field samples indicated that mixed populations of Las bacteria present in Floridian isolates, but only the Type D population was correlated with the blotchy mottle symptom. Extended cloning and sequencing of the Type D region revealed a third prophage/phage in the Las genome, which may derive from the recombination of FP1 and FP2. Dramatic variations in these prophage regions were also found among the global Las isolates. These results are the first to demonstrate the prophage/phage-mediated dynamics of Las populations in plant and insect hosts, and their correlation with insect transmission and disease development.

  5. Association of helminth infections and food consumption in common eiders Somateria mollissima in Iceland

    Science.gov (United States)

    Skirnisson, Karl

    2015-10-01

    Common eider Somateria mollissima L. 1758, subsp. borealis, is widely distributed along the coasts of Iceland. In this study association of parasite infections and food composition was studied among 40 females and 38 males (66 adults, 12 subadults), shot under license on four occasions within the same year (February; before egg-laying in May; after the breeding period in late June; and in November) in Skerjafjörður, SW Iceland. Parasitological examinations revealed 31 helminth species (11 digeneans, ten cestodes, seven nematodes, and three acanthocephalans). Distinct digenean species parasitized the gallbladder, kidney and bursa of Fabricius, whereas other helminths parasitized the gastrointestinal tract. Thirty-six invertebrate prey species were identified as food; waste and bread fed by humans, were also consumed by some birds. Amidostomum acutum was the only parasite found with a direct life cycle, whereas other species were food transmitted and ingested with different invertebrate prey. Opposite to females male birds rarely utilized periwinkles and gammarids as a food source. As a result, Microphallus and Microsomacanthus infection intensities were low except in February, when subadult males were responsible for an infection peak. Females caring for young increased their consumption of periwinkles close to the littoral zone in June; during pre-breeding, females also increased their gammarid intake. As a consequence, Microphallus and Microsomacanthus infection intensities temporarily peaked. Increased food intake (including Mytilus edulis) of females before the egg-laying period resulted in twofold higher Gymnophallus bursicola infection intensity than observed for males. Profilicollis botulus infection reflected seasonal changes in decapod consumption in both genders. Different life history strategies of males and females, especially before and during the breeding season and caring of young, and during molting in distinct feeding areas in summer, promote

  6. Reprint of 'Association of helminth infections and food consumption in common eiders Somateria mollissima in Iceland'

    Science.gov (United States)

    Skirnisson, Karl

    2016-07-01

    Common eider Somateria mollissima L. 1758, subsp. borealis, is widely distributed along the coasts of Iceland. In this study association of parasite infections and food composition was studied among 40 females and 38 males (66 adults, 12 subadults), shot under license on four occasions within the same year (February; before egg-laying in May; after the breeding period in late June; and in November) in Skerjafjörður, SW Iceland. Parasitological examinations revealed 31 helminth species (11 digeneans, ten cestodes, seven nematodes, and three acanthocephalans). Distinct digenean species parasitized the gallbladder, kidney and bursa of Fabricius, whereas other helminths parasitized the gastrointestinal tract. Thirty-six invertebrate prey species were identified as food; waste and bread fed by humans, were also consumed by some birds. Amidostomum acutum was the only parasite found with a direct life cycle, whereas other species were food transmitted and ingested with different invertebrate prey. Opposite to females male birds rarely utilized periwinkles and gammarids as a food source. As a result, Microphallus and Microsomacanthus infection intensities were low except in February, when subadult males were responsible for an infection peak. Females caring for young increased their consumption of periwinkles close to the littoral zone in June; during pre-breeding, females also increased their gammarid intake. As a consequence, Microphallus and Microsomacanthus infection intensities temporarily peaked. Increased food intake (including Mytilus edulis) of females before the egg-laying period resulted in twofold higher Gymnophallus bursicola infection intensity than observed for males. Profilicollis botulus infection reflected seasonal changes in decapod consumption in both genders. Different life history strategies of males and females, especially before and during the breeding season and caring of young, and during molting in distinct feeding areas in summer, promote

  7. Seasonal Abundance and Natural Inoculativity of Insect Vectors of Xylella fastidiosa in Oklahoma Tree Nurseries and Vineyards.

    Science.gov (United States)

    Overall, Lisa M; Rebek, Eric J

    2015-12-01

    Xylella fastidiosa is the causative agent of diseases of perennial plants including peach, plum, elm, oak, pecan, and grape. This bacterial pathogen is transmitted by xylem-feeding insects. In recent years, Pierce's disease of grape has been detected in 10 counties in central and northeastern Oklahoma, prompting further investigation of the disease epidemiology in this state. We surveyed vineyards and tree nurseries in Oklahoma for potential insect vectors to determine species composition, infectivity, and natural inoculativity of commonly captured insect vectors. Yellow sticky cards were used to sample insect fauna at each location. Insects were removed from sticky cards and screened for X. fastidiosa using immunocapture-PCR to determine their infectivity. A second objective was to test the natural inoculativity of insect vectors that are found in vineyards. Graphocephala versuta (Say), Graphocephala coccinea (Forster), Paraulacizes irrorata (F.), Oncometopia orbona (F.), Cuerna costalis (F.), and Entylia carinata Germar were collected from vineyards and taken back to the lab to determine their natural inoculativity. Immunocapture-PCR was used to test plant and insect samples for presence of X. fastidiosa. The three most frequently captured species from vineyards and tree nurseries were G. versuta, Clastoptera xanthocephala Germar, and O. orbona. Of those insects screened for X. fastidiosa, 2.4% tested positive for the bacterium. Field-collected G. versuta were inoculative to both ragweed and alfalfa. Following a 7-d inoculation access period, a higher percentage of alfalfa became infected than ragweed. Results from this study provide insight into the epidemiology of X. fastidiosa in Oklahoma. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  8. Determinants of spatial behavior of a tropical forest seed predator: The roles of optimal foraging, dietary diversification, and home range defense.

    Science.gov (United States)

    Palminteri, Suzanne; Powell, George V N; Peres, Carlos A

    2016-05-01

    Specialized seed predators in tropical forests may avoid seasonal food scarcity and interspecific feeding competition but may need to diversify their daily diet to limit ingestion of any given toxin. Seed predators may, therefore, adopt foraging strategies that favor dietary diversity and resource monitoring, rather than efficient energy intake, as suggested by optimal foraging theory. We tested whether fine-scale space use by a small-group-living seed predator-the bald-faced saki monkey (Pithecia irrorata)-reflected optimization of short-term foraging efficiency, maximization of daily dietary diversity, and/or responses to the threat of territorial encroachment by neighboring groups. Food patches across home ranges of five adjacent saki groups were widely spread, but areas with higher densities of stems or food species were not allocated greater feeding time. Foraging patterns-specifically, relatively long daily travel paths that bypassed available fruiting trees and relatively short feeding bouts in undepleted food patches-suggest a strategy that maximizes dietary diversification, rather than "optimal" foraging. Travel distance was unrelated to the proportion of seeds in the diet. Moreover, while taxonomically diverse, the daily diets of our study groups were no more species-rich than randomly derived diets based on co-occurring available food species. Sakis preferentially used overlapping areas of their HRs, within which adjacent groups shared many food trees, yet the density of food plants or food species in these areas was no greater than in other HR areas. The high likelihood of depletion by neighboring groups of otherwise enduring food sources may encourage monitoring of peripheral food patches in overlap areas, even if at the expense of immediate energy intake, suggesting that between-group competition is a key driver of fine-scale home range use in sakis. © 2015 Wiley Periodicals, Inc.

  9. Comparison of site descriptive models for Olkiluoto, Finland and Forsmark, Sweden

    Energy Technology Data Exchange (ETDEWEB)

    Geier, J.; Bath, A.; Stephansson, O.; Luukkonen, A.

    2012-08-15

    The proposed high-level radioactive waste repository sites at Olkiluoto and Forsmark share broadly similar geologic histories and regional settings. Despite differences in lithology, rock strength and patterns of brittle deformation, the sites show similarities in terms of hydrogeochemistry and hydrogeology. These similarities reflect a dominating influence of saline and brackish water intrusion during inundation by the postglacial Littorina Sea and Baltic Sea, followed by exposure to meteoric waters following postglacial uplift and transition to a Baltic coastal setting. Both sites also contain deep bedrock saline groundwater, though this is more evident at Olkiluoto than at Forsmark. A comparative study of site descriptive models for the two sites identifies the following key differences that could potentially impact safety of a repository: (1) Redox controls, buffering and biogeochemistry at proposed repository depths; (2) Salinity gradients at and below proposed repository depths; (3) Methane concentrations at and below proposed repository depths; (4) Depths to which glacial water and Littorina water penetrated; (5) Cation hydrogeochemistry and water-rock reaction; (6) Pore water compositions in rock matrix; (7) Rock fabric, secondary minerals and alteration with respect to radionuclide retention; (8) Brittle deformation fabric differences on multiple scales that affect vertical hydraulic conductivity; (9) Differences in apparent frequency of encountering water-conducting networks at proposed repository depths; (10) Shallow bedrock hydraulic properties; (11) Unique intrusive or dissolution features; (12) Connectivity of site-scale models to regional-scale features; (13) Mesoproterozoic rocks in vicinity and possibilities for human-intrusion scenarios; (14) Rock stresses and bedrock strength and deformability at proposed repository depths; (15) Thermal anisotropy. These differences are all potentially significant to safety functions, but none are so severe that

  10. Biologically-Oriented Processes in the Coastal Sea Ice Zone of the White Sea

    Science.gov (United States)

    Melnikov, I. A.

    2002-12-01

    The annual advance and retreat of sea ice is a major physical determinant of spatial and temporal changes in the structure and function of marine coastal biological communities. Sea ice biological data obtained in the tidal zone of Kandalaksha Gulf (White Sea) during 1996-2001 period will be presented. Previous observations in this area were mainly conducted during the ice-free summer season. However, there is little information on the ice-covered winter season (6-7 months duration), and, especially, on the sea-ice biology in the coastal zone within tidal regimes. During the January-May period time-series observations were conducted on transects along shorelines with coastal and fast ice. Trends in the annual extent of sea ice showed significant impacts on ice-associated biological communities. Three types of sea ice impact on kelps, balanoides, littorinas and amphipods are distinguished: (i) positive, when sea ice protects these populations from grinding (ii) negative, when ice grinds both fauna and flora, and (iii) a combined effect, when fast ice protects, but anchored ice grinds plant and animals. To understand the full spectrum of ecological problems caused by pollution on the coastal zone, as well as the problems of sea ice melting caused by global warming, an integrated, long-term study of the physical, chemical, and biological processes is needed.

  11. Spatial and temporal variations in concentration factors in NW European seas - secondary use of monitoring data

    Energy Technology Data Exchange (ETDEWEB)

    Kershaw, P.J.; Mcmahon, C.A.; Rudjord, A.L.; Smedley, C.; Nawakowski, C.; Leonard, K.S. [Centre for Environment, Fisheries and Aquaculture Science (CEFAS), Lowestoft (United Kingdom)

    2004-07-01

    This paper presents new data on concentration factors (CFs: concentration kg-1 biota/concentration l-1 seawater) for several marine species-radionuclide pairs, in three regions: coastal waters of Ireland, eastern Irish Sea, coastal waters of Norway. The CFs were estimated using data from long-term monitoring programmes, obtained for radiological protection purposes. The practical constraints of using such data sources are discussed. CFs were obtained for Mytilus edulis (mussels), Nephrops norvegicus (Norway lobster/Dublin Bay prawn/scampi), Pleuronectes platessa (plaice), Cancer pagurus (edible crab), Littorina littoria (winkles) and Fucus vesiculosus, for one or more of the following radionuclides: {sup 99}Tc, {sup 137}Cs, {sup 239,240}Pu and {sup 241}Am. In general, there was a relatively high degree of variability in the values obtained, and it was not possible to discern systematic regional or time-dependent differences. However, for two datasets in the eastern Irish Sea ({sup 137}Cs in winkles and crabs) there was a statistically-significant increase in the CF over the 40 year monitoring period. In several cases the range of values obtained exceeded the range recommended by the IAEA. In 2002, the average {sup 99}Tc CF for F. vesiculosus from the eastern Irish Sea coastline was 26, significantly lower than the IAEA recommended valve (1 x 10{sup 3} - 1 x 10{sup 5}).The results are discussed in relation to the influence of contemporaneous discharges and the possible impact of re-mobilised radionuclides. (author)

  12. Shell biofilm-associated nitrous oxide production in marine molluscs: processes, precursors and relative importance.

    Science.gov (United States)

    Heisterkamp, Ines M; Schramm, Andreas; Larsen, Lone H; Svenningsen, Nanna B; Lavik, Gaute; de Beer, Dirk; Stief, Peter

    2013-07-01

    Emission of the greenhouse gas nitrous oxide (N2 O) from freshwater and terrestrial invertebrates has exclusively been ascribed to N2 O production by ingested denitrifying bacteria in the anoxic gut of the animals. Our study of marine molluscs now shows that also microbial biofilms on shell surfaces are important sites of N2 O production. The shell biofilms of Mytilus edulis, Littorina littorea and Hinia reticulata contributed 18-94% to the total animal-associated N2 O emission. Nitrification and denitrification were equally important sources of N2 O in shell biofilms as revealed by (15) N-stable isotope experiments with dissected shells. Microsensor measurements confirmed that both nitrification and denitrification can occur in shell biofilms due to a heterogeneous oxygen distribution. Accordingly, ammonium, nitrite and nitrate were important drivers of N2 O production in the shell biofilm of the three mollusc species. Ammonium excretion by the animals was found to be sufficient to sustain N2 O production in the shell biofilm. Apparently, the animals provide a nutrient-enriched microenvironment that stimulates growth and N2 O production of the shell biofilm. This animal-induced stimulation was demonstrated in a long-term microcosm experiment with the snail H. reticulata, where shell biofilms exhibited the highest N2 O emission rates when the animal was still living inside the shell. © 2012 John Wiley & Sons Ltd and Society for Applied Microbiology.

  13. Spatial and seasonal variation in heavy metals in the sediments and biota of two adjacent estuaries, the Orwell and the Stour, in eastern England

    International Nuclear Information System (INIS)

    Wright, P.; Mason, C.F.

    1999-01-01

    A study was made of the concentrations of the elements As, Cd, Cu, Hg, Mn, Ni, Pb and Zn in the sediments and biota of two adjacent estuaries, the Orwell and Stour, in eastern England. The Orwell Estuary, with its urbanized head, was more contaminated with heavy metals than the Stour Estuary. Generally, in both estuaries, concentrations of metals were highest towards the head and the mouth. Saltmarsh sediments accumulated higher concentrations of most metals than mudflat sediments. Metal concentrations in the biota showed marked interspecific differences; Mytilus edulis had higher concentrations of Cd, Littorina littorea higher concentrations of Cu and Mn and Arenicola marina higher concentrations of Hg. Invertebrates from the Orwell had higher metal concentrations than those from the Stour. Algae had generally lower levels of metals than invertebrates. Metal concentrations were greatest and more variable in the top 10 cm of sediment. Metals were at greatest concentrations in winter and lowest in summer in sediments, algae and invertebrates. Mercury concentration increased with size in the three invertebrate species studied, but Cd and Zn generally were at higher concentrations in younger animals. Comparisons of sediments with average shale values indicated anthropogenic enrichment with several metals but it was considered that only Pb, at some sites, and possibly Hg posed potential threats to the ecology of the estuaries. (Copyright (c) 1999 Elsevier Science B.V., Amsterdam. All rights reserved.)

  14. Tributyltin accumulation and effects in marine molluscs from West Greenland

    Energy Technology Data Exchange (ETDEWEB)

    Strand, J.; Asmund, G

    2003-05-01

    Tributyltin is accumulated in marine molluscs living in Greenland, with the highest levels found in harbour areas. - The levels of the antifouling agent tributyltin (TBT) and its breakdown products in bivalves were investigated in 1999-2000 at six areas along the west coast of Greenland with focus on locations inside and outside harbours. In addition female gastropods were examined for the development of TBT-induced masculine characteristics in form of imposex or intersex. The highest TBT concentration, 254 ng g{sup -1} ww, was found in the bivalve Mytilus edulis sampled inside Nuuk harbour, but significant TBT concentrations were also present in bivalves from the other harbour areas. Only low levels of TBT were detected in bivalves sampled outside the harbours and in several of the samples the TBT level was below the detection limit. The examination of neogastropods like Buccinum revealed that imposex development occurred in all the harbours. In contrast, imposex was not found in any neogastropods sampled outside the harbour areas. However, the value of marine neogastropods as indicators of TBT contamination in West Greenland seems limited, because of large species diversity and the difficulties in sampling enough specimens at least with the current sampling strategy. No effects, which could be related to TBT contamination, were found in the most abundant tidal gastropod in West Greenland, Littorina saxatilis.

  15. Estructura comunitaria de bivalvos y gasterópodos en raíces del mangle rojo Rhizophora mangle (Rhizophoraceae en isla Larga, bahía de Mochima, Venezuela

    Directory of Open Access Journals (Sweden)

    Vanessa Acosta Balbas

    2014-08-01

    Full Text Available Las raíces del mangle rojo forman un complejo ecosistema donde se reproducen, refugian y establecen de manera permanente una gran diversidad de organismos. En este estudio, se evaluó la diversidad de bivalvos y gasterópodos que habitan las raíces del mangle rojo Rhizophora mangle, en isla Larga, Bahía de Mochima, estado Sucre Venezuela. Se realizaron recolectas bimensuales desde enero 2007 hasta mayo 2008, en cuatro zonas de estudio denominadas: zona sur, norte, este y oeste. En cada zona se muestrearon cinco raíces de mangle, de donde se obtuvieron los especímenes. Se analizaron un total 180 raíces y se contabilizaron 35 especies de bivalvos y 25 de gasterópodos. Los bivalvos más abundantes fueron: Isognomon alatus, Isognomon bicolor, Ostrea equestris, Crassostrea rhizophorae y Brachidontes exustus, mientras que los gasterópodos más frecuentes: Littorina angulifera, Cymatium pileare y Diodora cayenensis. Los meses donde se observaron las mayores abundancias de especies y número de individuos fueron enero y julio 2007 y marzo 2008. El ecosistema de manglar en isla Larga, presentó un número de individuos y especies superior al reportado en otros trabajos realizados en Venezuela y otras regiones del Caribe.

  16. Biology of Crassicutis cichlasomae, a parasite of cichlid fishes in Mexico and Central America.

    Science.gov (United States)

    Scholz, T; Pech-Ek, M C; Rodriguez-Canul, R

    1995-03-01

    Field study on the biology of Crassicutis cichlasomae Manter, 1936 (Digenea: Homalometridae) was carried out in a small swamp in a limestone factory near Mérida, Yucatán, Mexico. Aquatic snails, Littorina (Littoridinopis) angulifera, harbouring C. cichlasomae rediae, cercariae and metacercariae, served both as the first and second intermediate hosts. Feeding experiments confirmed the conspecificity of metacercariae from naturally infected snails with adults from naturally infected fish. Gravid C. cichlasomae worms were obtained from experimentally infected fish 19 days post exposure at 22-24 degrees C. Examination of fish from the swamp in Mitza and other localities in the Yucatan Peninsula showed that the cichlids Cichlasoma urophthalmus and C. meeki were definitive hosts of C. cichlasomae. There was no pronounced preference of C. cichlasomae adults for the site of their location in the intestine of the definitive host; a slightly higher proportion (41%) of worms was only found in the anterior third of the gut. The time of miracidium development varied from 18.5 to 27.5 days; different temperature (20.1-35.7 degrees C) or light/darkness regimes influenced only slightly the rate of embryonic development, with shorter development times at higher temperature (34.8-35.7 degrees C) and constant darkness and/or light. With the exception of the sporocyst, all developmental stages are described and figured.

  17. Tributyltin accumulation and effects in marine molluscs from West Greenland

    International Nuclear Information System (INIS)

    Strand, J.; Asmund, G.

    2003-01-01

    Tributyltin is accumulated in marine molluscs living in Greenland, with the highest levels found in harbour areas. - The levels of the antifouling agent tributyltin (TBT) and its breakdown products in bivalves were investigated in 1999-2000 at six areas along the west coast of Greenland with focus on locations inside and outside harbours. In addition female gastropods were examined for the development of TBT-induced masculine characteristics in form of imposex or intersex. The highest TBT concentration, 254 ng g -1 ww, was found in the bivalve Mytilus edulis sampled inside Nuuk harbour, but significant TBT concentrations were also present in bivalves from the other harbour areas. Only low levels of TBT were detected in bivalves sampled outside the harbours and in several of the samples the TBT level was below the detection limit. The examination of neogastropods like Buccinum revealed that imposex development occurred in all the harbours. In contrast, imposex was not found in any neogastropods sampled outside the harbour areas. However, the value of marine neogastropods as indicators of TBT contamination in West Greenland seems limited, because of large species diversity and the difficulties in sampling enough specimens at least with the current sampling strategy. No effects, which could be related to TBT contamination, were found in the most abundant tidal gastropod in West Greenland, Littorina saxatilis

  18. Molecular characterisation of dissolved organic matter (DOM) in groundwaters from the Aespoe Underground Research Laboratory (Sweden)): A novel 'finger printing' tool for palaeo-hydrological assessment

    International Nuclear Information System (INIS)

    Vane, C. H.; Kim, A. W.; Milodowski, A. E.; Smellie, J.; Tullborg, E. L.; West, J. M.

    2008-01-01

    The molecular signature of dissolved organic matter (DOM) in groundwaters can be used as a tool when investigating the palaeo-hydrological response of groundwater systems in relation to changes in recharge environment, and also for examining groundwater compartmentalisation, mixing and transport at underground repositories for radioactive waste. The DOM in groundwaters from two compartmentalised bodies of groundwater of distinctly different origin within the Aespoe Underground Research Laboratory (URL) (Sweden)) and in Baltic seawater has been isolated using tangential flow ultrafiltration (TUF) and dia-filtration. Recoveries of DOM ranged from 34.7 to 0.1 mg/L with substantial differences in the concentrations of the groundwaters collected only 120 m apart. Analysis by infrared spectroscopy (IR) and pyrolysis gas chromatography-mass spectrometry (Py-GC-MS) of the isolated DOM revealed that the groundwaters contained abundant alkylphenols which may represent heavily decomposed proteins or lignins originating from biopolymers contained within soils. The difference in the distribution and relative abundance of major pyrolysis products groups such as alkylphenols confirmed that the groundwater and Baltic seawater DOM samples were chemically distinct indicating minimal infiltration of marine groundwater derived by recharge from the Baltic or earlier Littorina Sea within the two compartmentalised groundwater bodies. (authors)

  19. Assessment of PAHs levels in some fish and seafood from different coastal waters in the Niger Delta.

    Science.gov (United States)

    Nwaichi, E O; Ntorgbo, S A

    2016-01-01

    Levels of sixteen polycyclic aromatic hydrocarbons (PAHs) in 30 edible tissues of selected frequently-consumed fish and seafood collected from three coastal waters of Niger Delta, namely, Sime, Kporghor and Iko were investigated in 2014. Gas chromatographic analysis were employed for PAHs determination. Observed mean PAHs levels in the samples ranged from below detection limit (BD) of analytical instrument to 22.400 ± 0.050 μg kg -1 wet wt. in Littorina littorea, BD to 87.400 ± 0.030 μg kg -1 wet wt. in Crassostrea virginica and from BD to 171.000 ± 0.430 μg kg -1 wet wt. in Periophthalmus koeleuteri. The highest average concentration of 171.000 ± 0.430 μg kg -1 wet wt. was recorded for Indeno [1,2,3-cd]pyrene from Sime water. High molecular weight PAHs (HMW-PAHs) were generally predominant compared to low molecular weight PAHs (LMW-PAHs). The LMW- PAH/HMW-PAH ratio was waters of Niger Delta environment. Moreover, the study of the PAHs fingerprints, using specific ratios, suggests the predominance of a pyrolytic origin for observed PAHs.

  20. Long-term effects of the water-accomodated fraction (WAF) of diesel oil on rocky shore populations maintained in experimental mesocosms

    Energy Technology Data Exchange (ETDEWEB)

    Bokn, T.L. [Norwegian Inst. for Water Research, Oslo (Norway); Moy, F.E. [Norwegian Inst. for Water Research, Oslo (Norway); Murray, S.N. [California State Univ., Fullerton, CA (United States). Dept. of Biological Science

    1993-12-31

    The long-term effects of continuous doses (average hydrocarbon concentration =129.4 {mu}g L{sup -1} and 30.1 {mu}g L{sup -1}) of the water-accommodated fraction (WAF) of diesel oil on 15 rocky littoral populations were determined at three tidal levels in experimental mesocosms over two years. At each tidal level, most species exhibited similar abundance changes in both oil-contaminated and control (average background hydrocarbon concentration = 5.6 {mu}g L{sup -1}) mesocosms. Significant changes in species abundances attributable to oil (WAF) were demonstrated for only two of ten seaweeds and three of five invertebrates. Compared with the other mesocosms, significantly greater reductions in upper-level cover were recorded in the basin receiving the highest oil dosage for the seaweeds Phymatolithon lenormandii and Fucus evanescents together with lower recruitment of the barnacle Semibalanus balanoides. The mussel Mytilus edulis was storngly affected by the oil treatments and essentially disappeared from both oil-contaminated mesocosms. Numbers of the starfish Asterias rubens also fell to zero at the lowest tidal level in the basin receiving the highest oil dosage. There were no demonstrable differences in the abundance patterns of the gastropod Littorina littorea, the crab Carcinus maenus, and a total of eight brown (Ascophyllum nodosum, Fucus serratus, F. vesiculosus, Laminaria digitata), red (Chondrus crispus), and green (Cladophora rupestris, Enteromorpha spp., Ulva lactuca) seaweeds in the oil-contaminated compared with the control mesocosms. (orig.)

  1. Long-term effects of the water-accomodated fraction (WAF) of diesel oil on rocky shore populations maintained in experimental mesocosms

    International Nuclear Information System (INIS)

    Bokn, T.L.; Moy, F.E.; Murray, S.N.

    1993-01-01

    The long-term effects of continuous doses (average hydrocarbon concentration =129.4 μg L -1 and 30.1 μg L -1 ) of the water-accommodated fraction (WAF) of diesel oil on 15 rocky littoral populations were determined at three tidal levels in experimental mesocosms over two years. At each tidal level, most species exhibited similar abundance changes in both oil-contaminated and control (average background hydrocarbon concentration = 5.6 μg L -1 ) mesocosms. Significant changes in species abundances attributable to oil (WAF) were demonstrated for only two of ten seaweeds and three of five invertebrates. Compared with the other mesocosms, significantly greater reductions in upper-level cover were recorded in the basin receiving the highest oil dosage for the seaweeds Phymatolithon lenormandii and Fucus evanescents together with lower recruitment of the barnacle Semibalanus balanoides. The mussel Mytilus edulis was storngly affected by the oil treatments and essentially disappeared from both oil-contaminated mesocosms. Numbers of the starfish Asterias rubens also fell to zero at the lowest tidal level in the basin receiving the highest oil dosage. There were no demonstrable differences in the abundance patterns of the gastropod Littorina littorea, the crab Carcinus maenus, and a total of eight brown (Ascophyllum nodosum, Fucus serratus, F. vesiculosus, Laminaria digitata), red (Chondrus crispus), and green (Cladophora rupestris, Enteromorpha spp., Ulva lactuca) seaweeds in the oil-contaminated compared with the control mesocosms. (orig.)

  2. Temporal changes of 210Po in temperate coastal waters

    International Nuclear Information System (INIS)

    Wildgust, M.A.; White, K.N.; McDonald, P.

    1998-01-01

    The temporal variation of Polonium-210 ( 210 Po) was examined in coastal sea water, the mussel Mytilus edulis, the winkle Littorina littorea and green algae Ulva lactuca in order to investigate the entry of 210 Po into the marine food chain. More than 99% of 210 Po in the water column occurred in the particulate phase. Dissolved 210 Po concentrations peaked during the spring phytoplankton bloom and it is suggested this is related to preferential scavenging of 210 Po by the increased numbers of bacteria, viruses and small dissolved particulates. Changes in L. Littorea 210 Po specific activity are thought not to be related to food, but to a drop in body weight following spawning. Much of the 210 Po accumulated by M. edulis was located in the digestive gland. The specific activity of 210 Po in the digestive gland of M. edulis was shown to be strongly correlated with changes in sea water suspended particulate specific activity. Examination of other trace metal (Ag, Al, As, Ca, Cd, Cr, Co, Cu, Fe, Hg, K, Mg, Mn, Na, Ni Sb, Se, Sn and Zn) variations in the digestive gland revealed that class B and borderline metals had a strong positive correlation with 210 Po. On-going work is investigating whether the accumulation and loss of 210 Po is affected by the presence of metallothioneins

  3. Hydrogeochemical evaluation. Preliminary site description Forsmark area - version 1.2

    International Nuclear Information System (INIS)

    Laaksoharju, Marcus

    2005-03-01

    discharge. Most lines of evidence support that the sulphur system, microbiologically mediated, is the main redox controller in the deepest and most saline groundwaters. On the other hand, Littorina-rich brackish groundwaters show variable and very high iron contents, in agreement with what has been observed in similar groundwaters elsewhere. The microbial analyses only found trace amounts of sulphate reducing bacteria (SRB) in these samples, but very high numbers of iron-reducing bacteria (IRB). However, there is no correlation between Fe 2+ concentration and the number of IRB in these groundwaters. Moreover, they show very low but detectable contents of dissolved S 2- and the δ 34 S values are very homogeneous (around 2.5%) and clearly higher than in the present Baltic Sea, indicating that sulphate reduction has operated. These observations could support the existence of an iron-sulphide precipitation process during the Littorina Sea phase of these groundwaters but not intense enough to effectively limit Fe 2+ solubility. A modelling approach was used to simulate the obtained groundwater in the Forsmark area by introducing Littorina Sea water. These results indicate that re-equilibrium reaction processes are important in the control of some parameters such as pH (as well as Eh, and some minor trace elements), moving the waters towards the adularia-albite boundary. However, the main compositional changes, and even the extent of re-equilibration processes, are controlled by the extent of the mixing process. Coupled transport modelling was used to model the measured water conservative elements, tritium contents and the water recharge into the granitic bedrock. The simulations indicate that quaternary sediments may play a significant role since most of the infiltrated water could flow through the conductive layers in the sediment to discharge zones, mainly associated with lakes and the Baltic Sea coast line. Based on this hypothesis, the effective recharge into the granitic

  4. Temporal changes of 210Po in temperate coastal waters.

    Science.gov (United States)

    Wildgust, M A; McDonald, P; White, K N

    1998-06-18

    The temporal variation of Polonium-210 (210Po) was examined in coastal sea water, the mussel Mytilus edulis, the winkle Littorina littorea and green alga Ulva lactuca in order to investigate the entry of 210Po into the marine food chain. More than 99% of 210Po in the water column occurred in the particulate phase. Dissolved 210Po concentrations peaked during the spring phytoplankton bloom and it is suggested this is related to preferential scavenging of 210Po by the increased numbers of bacteria, viruses and small dissolved particulates. Changes in L. littorea 210Po specific activity are thought not to be related to food, but to a drop in body weight following spawning. Much of the 210Po accumulated by M. edulis was located in the digestive gland. The specific activity of 210Po in the digestive gland of M. edulis was shown to be strongly correlated with changes in sea water suspended particulate specific activity. Examination of other trace metal (Ag, Al, As, Ca, Cd, Cr, Co, Cu, Fe, Hg, K, Mg, Mn, Na, Ni, Sb, Se, Sn and Zn) variations in the digestive gland revealed that class B and borderline metals had a strong positive correlation with 210Po. On-going work is investigating whether the accumulation and loss of 210Po is affected by the presence of metallothioneins.

  5. Distribution of radionuclides in mussels, winkles and prawns: Pt. 1; Study of organisms under environmental conditions using conventional radio-analytical techniques

    Energy Technology Data Exchange (ETDEWEB)

    McDonald, P [Scottish Research Reactor Centre, East Kilbride (United Kingdom); Baxter, M S; Fowler, S W [International Atomic Energy Agency, Monaco (Monaco). Marine Environment Lab.

    1993-01-01

    Mussels (Mytilus edulis) and winkles (Littorina littorea), collected from Ravenglass, Cumbria, England in the vicinity of the British Nuclear Fuels plc nuclear reprocessing plant at Sellafield, and prawns (Palaemon serratus), landed nearby at Whitehaven, have been investigated to determine the distributions of [alpha]-emitting ([sup 210]Po, [sup 238]Pu, [sup 239] [sup +] [sup 240]Pu, [sup 241]Am) and [gamma]-emitting ([sup 95]Nb, [sup 95]Zr, [sup 103]Ru, [sup 106]Ru, [sup 137]Cs, [sup 241]Am) radionuclides in their tissues and organs. Previous studies have attempted to determine the principal nuclide source to marine organisms by comparing nuclide activity ratios in their tissues, sea water and particulate material. From the environmental samples studied here, no single transport medium appears to dominate uptake. The primary radiological implantation of the observed radionuclide concentrations in Ravenglass mussels and winkles is that, from seafood ingestion, the critical group receives only a small percentage (ca. 10%) of the ICRP-recommended subsidiary dose limit. Dose contributions from [sup 210]Po are higher than those from [sup 239] + [sup 240]Pu in mussels but are less than those from [sup 239] [sup +] [sup 240]Pu in winkles. (Author).

  6. Hydrogeochemical evaluation. Preliminary site description Forsmark area - version 1.2

    Energy Technology Data Exchange (ETDEWEB)

    Laaksoharju, Marcus (ed.) [Geopoint AB, Stockholm (Sweden)

    2005-03-15

    groundwater discharge. Most lines of evidence support that the sulphur system, microbiologically mediated, is the main redox controller in the deepest and most saline groundwaters. On the other hand, Littorina-rich brackish groundwaters show variable and very high iron contents, in agreement with what has been observed in similar groundwaters elsewhere. The microbial analyses only found trace amounts of sulphate reducing bacteria (SRB) in these samples, but very high numbers of iron-reducing bacteria (IRB). However, there is no correlation between Fe{sup 2+} concentration and the number of IRB in these groundwaters. Moreover, they show very low but detectable contents of dissolved S{sup 2-} and the {delta}{sup 34}S values are very homogeneous (around 2.5%) and clearly higher than in the present Baltic Sea, indicating that sulphate reduction has operated. These observations could support the existence of an iron-sulphide precipitation process during the Littorina Sea phase of these groundwaters but not intense enough to effectively limit Fe{sup 2+} solubility. A modelling approach was used to simulate the obtained groundwater in the Forsmark area by introducing Littorina Sea water. These results indicate that re-equilibrium reaction processes are important in the control of some parameters such as pH (as well as Eh, and some minor trace elements), moving the waters towards the adularia-albite boundary. However, the main compositional changes, and even the extent of re-equilibration processes, are controlled by the extent of the mixing process. Coupled transport modelling was used to model the measured water conservative elements, tritium contents and the water recharge into the granitic bedrock. The simulations indicate that quaternary sediments may play a significant role since most of the infiltrated water could flow through the conductive layers in the sediment to discharge zones, mainly associated with lakes and the Baltic Sea coast line. Based on this hypothesis, the

  7. Heavy Metals in Seafood and Farm Produce from Uyo, Nigeria; Levels and health implications

    Directory of Open Access Journals (Sweden)

    Orish E. Orisakwe

    2015-05-01

    Full Text Available Objectives: This study aimed to obtain representative data on the levels of heavy metals in seafood and farm produce consumed by the general population in Uyo, Akwa Ibom State, Nigeria, a region known for the exploration and exploitation of crude oil. Methods: In May 2012, 25 food items, including common types of seafood, cereals, root crops and vegetables, were purchased in Uyo or collected from farmland in the region. Dried samples were ground, digested and centrifuged. Levels of heavy metals (lead, cadmium, nickel, cobalt and chromium were analysed using an atomic absorption spectrophotometer. Average daily intake and target hazard quotients (THQ were estimated. Results: Eight food items (millet, maize, periwinkle, crayfish, stock fish, sabina fish, bonga fish and pumpkin leaf had THQ values over 1.0 for cadmium, indicating a potential health risk in their consumption. All other heavy metals had THQ values below 1.0, indicating insignificant health risks. The total THQ for the heavy metals ranged from 0.389 to 2.986. There were 14 items with total THQ values greater than 1.0, indicating potential health risks in their consumption. Conclusion: The regular consumption of certain types of farm produce and seafood available in Uyo, Akwa Ibom State, Nigeria, is likely adding to the body burden of heavy metals among those living in this region.

  8. Imaging characteristics of supratentorial ependymomas: Study on a large single institutional cohort with histopathological correlation.

    Science.gov (United States)

    Mangalore, Sandhya; Aryan, Saritha; Prasad, Chandrajit; Santosh, Vani

    2015-01-01

    Supratentorial ependymoma (STE) is a tumor whose unique clinical and imaging characteristics have not been studied. Histopathologically, they resemble ependymoma elsewhere. We retrospectively reviewed the imaging findings with clinicopathological correlation in a large number of patients with STE to identify these characteristics. Computed tomography (CT) magnetic resonance images (MRI), pathology reports, and clinical information from 41 patients with pathology-confirmed STE from a single institution were retrospectively reviewed. CT and MRI findings including location, size, signal intensity, hemorrhage, and enhancement pattern were tabulated and described separately in intraventricular and intraparenchymal forms. STE was more common in pediatric age group and intraparenchymal was more common than intraventricular form. The most common presentation was features of raised intracranial tension. There were equal numbers of Grade II and Grade III tumors. The imaging characteristics in adult and pediatric age group were similar. The tumor was large and had both solid and cystic components. Advanced imaging such as diffusion, perfusion, and spectroscopy were suggestive of high-grade tumor. Only differentiating factor between Grade II and Grade III was the presence of calcification. 1234 rule and periwinkle sign which we have described in this article may help characterize this tumor on imaging. This series expands the clinical and imaging spectrum of STE and identifies characteristics that should suggest consideration of this uncommon diagnosis.

  9. Prequels to Synthetic Biology: From Candidate Gene Identification and Validation to Enzyme Subcellular Localization in Plant and Yeast Cells.

    Science.gov (United States)

    Foureau, E; Carqueijeiro, I; Dugé de Bernonville, T; Melin, C; Lafontaine, F; Besseau, S; Lanoue, A; Papon, N; Oudin, A; Glévarec, G; Clastre, M; St-Pierre, B; Giglioli-Guivarc'h, N; Courdavault, V

    2016-01-01

    Natural compounds extracted from microorganisms or plants constitute an inexhaustible source of valuable molecules whose supply can be potentially challenged by limitations in biological sourcing. The recent progress in synthetic biology combined to the increasing access to extensive transcriptomics and genomics data now provide new alternatives to produce these molecules by transferring their whole biosynthetic pathway in heterologous production platforms such as yeasts or bacteria. While the generation of high titer producing strains remains per se an arduous field of investigation, elucidation of the biosynthetic pathways as well as characterization of their complex subcellular organization are essential prequels to the efficient development of such bioengineering approaches. Using examples from plants and yeasts as a framework, we describe potent methods to rationalize the study of partially characterized pathways, including the basics of computational applications to identify candidate genes in transcriptomics data and the validation of their function by an improved procedure of virus-induced gene silencing mediated by direct DNA transfer to get around possible resistance to Agrobacterium-delivery of viral vectors. To identify potential alterations of biosynthetic fluxes resulting from enzyme mislocalizations in reconstituted pathways, we also detail protocols aiming at characterizing subcellular localizations of protein in plant cells by expression of fluorescent protein fusions through biolistic-mediated transient transformation, and localization of transferred enzymes in yeast using similar fluorescence procedures. Albeit initially developed for the Madagascar periwinkle, these methods may be applied to other plant species or organisms in order to establish synthetic biology platform. © 2016 Elsevier Inc. All rights reserved.

  10. Worms at war: interspecific parasite competition and host resources alter trematode colony structure and fitness.

    Science.gov (United States)

    Mouritsen, Kim N; Andersen, Cecillie

    2017-09-01

    Parasites competing over limited host resources are faced with a tradeoff between reproductive success and host overexploitation jeopardizing survival. Surprisingly little is known about the outcome of such competitive scenarios, and we therefore aimed at elucidating interactions between the trematodes Himasthla elongata and Renicola roscovita coinfecting the periwinkle first intermediate host. The results show that the success of Himasthla colonies (rediae) in terms of cercarial emission is unaffected by Renicola competition (sporocysts), whereas deteriating host condition decreases fitness. Furthermore, double infection has no bearing on Himasthla's colony size but elevated the proportion of non-reproductive rediae that play a decisive role in colony defence. Opposite, the development of the Renicola colony (size/maturity), and in turn fitness, is markedly reduced in presence of Himasthla, whereas the nutritional state of the host appears less important. Hence, the intramolluscan competition between Himasthla and Renicola is asymmetrical, Himasthla being the superior competitor. Himasthla not only adjusts its virulence according to the hosts immediate nutritional state, it also nullifies the negative impact of a heterospecific competitor on own fitness. The latter is argued to follow in part from direct predation on the competitor, for which purpose more defensive non-reproductive rediae are strategically produced.

  11. A review on seashells ash as partial cement replacement

    Science.gov (United States)

    Mohammad, Wan Ahmad Soffian Bin Wan; Hazurina Othman, Nor; Ibrahim, Mohd Haziman Wan; Rahim, Masazurah A.; Shahidan, Shahiron; Rahman, Raha Abd

    2017-11-01

    This review paper emphasis on various sea shells ash such as cockle, clam, oyster, mollusc, periwinkle, snail, and green mussel shell ash as partial cement replacement and its objective is to create sustainable environment and reduce problems of global warming. Cement production give huge impact to environment in every stage of its production. These include air pollution in form of dust and, gases, sound and vibration during quarry crushing and milling. One of the solutions to solve this problem is by using modified cement. The modified cement is a cementitious material that meets or exceeds the Portland cement performance by combining and optimizes the recycle and wasted materials. This will indirectly reduce the use of raw materials and then, become a sustain construction materials. Therefore, the replacement of cement in concrete by various sea shell ash may create tremendous saving of energy and also leads to important environmental benefits. This study includes previous investigation done on the properties of chemical and mechanical such as specific gravity, chemical composition, compressive strength, tensile strength and flexural strength of concrete produced using partial replacement of cement by seashells ash. Results show that the optimum percentage of seashells as cement replacement is between 4 - 5%.

  12. Transcriptome Analysis of the Phytobacterium Xylella fastidiosa Growing under Xylem-Based Chemical Conditions

    Directory of Open Access Journals (Sweden)

    Maristela Boaceff Ciraulo

    2010-01-01

    Full Text Available Xylella fastidiosa is a xylem-limited bacterium responsible for important plant diseases, like citrus-variegated chlorosis (CVC and grapevine Pierce's disease (PD. Interestingly, in vitro growth of X. fastidiosa in chemically defined media that resemble xylem fluid has been achieved, allowing studies of metabolic processes used by xylem-dwelling bacteria to thrive in such nutrient-poor conditions. Thus, we performed microarray hybridizations to compare transcriptomes of X. fastidiosa cells grown in 3G10-R, a medium that resembles grape sap, and in Periwinkle Wilt (PW, the complex medium traditionally used to cultivate X. fastidiosa. We identified 299 transcripts modulated in response to growth in these media. Some 3G10R-overexpressed genes have been shown to be upregulated in cells directly isolated from infected plants and may be involved in plant colonization, virulence and environmental competition. In contrast, cells cultivated in PW show a metabolic switch associated with increased aerobic respiration and enhanced bacterial growth rates.

  13. Isolation and pathogenicity of Xylella fastidiosa from grapevine and almond in Iran

    Directory of Open Access Journals (Sweden)

    Naser AMANIFAR

    2014-09-01

    Full Text Available Symptoms similar to those of Pierce’s disease (PD of grapevine and leaf scorch of almond were observed in vineyards and almond orchards in several provinces of Iran. Grafting of scions from symptomatic almond trees onto seedlings of a local almond (cv. Mamaee under greenhouse conditions resulted in the transmission of the leaf scorch agent. A number of symptomatic samples from orchard and greenhouse plants were positive for presence of Xylella fastidiosa when tested by DAS-ELISA and PCR with X. fastidiosa specific antibodies and primers. A Gram-negative bacterium similar to X. fastidiosa was isolated on ‘periwinkle wilt’ (PW medium. Selected isolates induced symptoms similar to those caused by X. fastidiosa when inoculated on Nicotiana tabacum, seedlings of almond and grapevine under greenhouse conditions. DAS-ELISA and PCR confirmed the identity of the isolated bacteria. On the basis of disease symptoms, graft transmission, isolation on specific X. fastidiosa culture medium, pathogenicity tests and positive reactions in DAS-ELISA and PCR, X. fastidiosa is associated with almond leaf scorch and Pierce’s disease in grapevine in Iran. This is the first report on the presence of X. fastidiosa in the Middle East and western Asia.

  14. Tapped density optimisation for four agricultural wastes - Part II: Performance analysis and Taguchi-Pareto

    Directory of Open Access Journals (Sweden)

    Ajibade Oluwaseyi Ayodele

    2016-01-01

    Full Text Available In this attempt, which is a second part of discussions on tapped density optimisation for four agricultural wastes (particles of coconut, periwinkle, palm kernel and egg shells, performance analysis for comparative basis is made. This paper pioneers a study direction in which optimisation of process variables are pursued using Taguchi method integrated with the Pareto 80-20 rule. Negative percentage improvements resulted when the optimal tapped density was compared with the average tapped density. However, the performance analysis between optimal tapped density and the peak tapped density values yielded positive percentage improvements for the four filler particles. The performance analysis results validate the effectiveness of using the Taguchi method in improving the tapped density properties of the filler particles. The application of the Pareto 80-20 rule to the table of parameters and levels produced revised tables of parameters and levels which helped to identify the factor-levels position of each parameter that is economical to optimality. The Pareto 80-20 rule also produced revised S/N response tables which were used to know the relevant S/N ratios that are relevant to optimality.

  15. The Eschericia coli Growth Inhibition Activity of Some Fermented Medicinal Plant Leaf Extract from the Karo Highland, North Sumatra

    Directory of Open Access Journals (Sweden)

    NOVIK NURHIDAYAT

    2009-10-01

    Full Text Available A lot of traditional medicinal plant has antibacterial acitivities. Most of these plants are freshly chewed or grounded and used directly to treat infectious bacterial deseases. However, some practices employ a traditionally spontaneous fermentation on boiled extracted leaf, root or other parts of the plant. This work reports a laboratory stimulated spontaneous fermentation of leaf extracts from selected medicinal plants collected from the Karo Higland. The spontaenous fermentation was stimulated to be carried out by the Acetobacter xylinum and Saccharomyces cerevisiae. The anti-infectious agent activity was assayed on the Eschericia coli growth inhibition. A complementary non fermented leaf extract was also made and assayed as a comparative measure. Indeed, the fermented leaf extract of bitter bush (Eupatorium pallescens, cacao (Theobroma cacao, avocado (Persia gratissima, passion fruit (Passiflora edulis, cassava (Cassava utillissima, diamond flower (Hedyotis corymbosa, periwinkle (Catharanthus roseus, and gandarusa (Justicia gendarussa have relatively higher anti-E.coli acitivity than those of non fermented ones. However, there were no anti-E.coli activity was detected in both fermented and non fermented leaf extract of the guava (Psidium guajava and common betel (Piper nigrum.

  16. The bHLH transcription factor BIS1 controls the iridoid branch of the monoterpenoid indole alkaloid pathway in Catharanthus roseus

    Science.gov (United States)

    Van Moerkercke, Alex; Steensma, Priscille; Schweizer, Fabian; Pollier, Jacob; Gariboldi, Ivo; Payne, Richard; Vanden Bossche, Robin; Miettinen, Karel; Espoz, Javiera; Purnama, Purin Candra; Kellner, Franziska; Seppänen-Laakso, Tuulikki; O’Connor, Sarah E.; Rischer, Heiko; Memelink, Johan; Goossens, Alain

    2015-01-01

    Plants make specialized bioactive metabolites to defend themselves against attackers. The conserved control mechanisms are based on transcriptional activation of the respective plant species-specific biosynthetic pathways by the phytohormone jasmonate. Knowledge of the transcription factors involved, particularly in terpenoid biosynthesis, remains fragmentary. By transcriptome analysis and functional screens in the medicinal plant Catharanthus roseus (Madagascar periwinkle), the unique source of the monoterpenoid indole alkaloid (MIA)-type anticancer drugs vincristine and vinblastine, we identified a jasmonate-regulated basic helix–loop–helix (bHLH) transcription factor from clade IVa inducing the monoterpenoid branch of the MIA pathway. The bHLH iridoid synthesis 1 (BIS1) transcription factor transactivated the expression of all of the genes encoding the enzymes that catalyze the sequential conversion of the ubiquitous terpenoid precursor geranyl diphosphate to the iridoid loganic acid. BIS1 acted in a complementary manner to the previously characterized ethylene response factor Octadecanoid derivative-Responsive Catharanthus APETALA2-domain 3 (ORCA3) that transactivates the expression of several genes encoding the enzymes catalyzing the conversion of loganic acid to the downstream MIAs. In contrast to ORCA3, overexpression of BIS1 was sufficient to boost production of high-value iridoids and MIAs in C. roseus suspension cell cultures. Hence, BIS1 might be a metabolic engineering tool to produce sustainably high-value MIAs in C. roseus plants or cultures. PMID:26080427

  17. Preliminary Hydrogeochemical Site Description SFR (version 0.2)

    Energy Technology Data Exchange (ETDEWEB)

    Nilsson, Ann-Chatrin (Geosigma AB, Uppaala (Sweden)); Tullborg, Eva-Lena (Terralogica AB, Graabo (Sweden)); Smellie, John (Conterra AB, Partille (Sweden))

    2010-05-15

    in accordance with the chemistry of Fe, Mn, S and U, it is concluded that mildly reducing conditions (.140 to .190 mV) generally prevail in the investigated groundwaters. This is in line with measured Eh values in brackish marine waters of Littorina type from the site investigations in Forsmark and Laxemar (PLU). Hydrogeochemical observations together with palaeoclimatic considerations were used to differentiate the groundwaters into four major types; 1) local Baltic Sea water type, 2) Littorina type water with a glacial component, 3) brackish glacial water type, and 4) mixed brackish water (transition type). Explorative analyses using traditional geochemical approaches have been performed to describe groundwater conditions (origin and evolution) and other properties (mixing and reactions) in more detail. The division into groundwater types has facilitated interaction and integration with the hydrogeological models making it possible to construct a hydrogeochemical site descriptive model for the SFR site. The distribution of the different groundwater types shows that the major deformation zones have served as important groundwater flow pathways over long periods of geological time while single fractures in rock volumes between zones generally contain older and more isolated groundwater. Presently, the steeply dipping structures in particular have facilitated the drawdown of modern Baltic Sea water which has been observed since excavation and construction of the SFR some twenty years ago. Understanding the evolution of the groundwater system over time, i.e. since the last glaciation and more recently since excavation and construction of the SFR repository, shows that: 1) present-day hydraulic conditions have preserved groundwater patterns which replicate to a large extent what will occur during the next deglaciation (long-term perspective), and 2) the future impact of extended excavations and underground construction on groundwater chemistry can be predicted from past

  18. Preliminary Hydrogeochemical Site Description SFR (version 0.2)

    International Nuclear Information System (INIS)

    Nilsson, Ann-Chatrin; Tullborg, Eva-Lena; Smellie, John

    2010-05-01

    in accordance with the chemistry of Fe, Mn, S and U, it is concluded that mildly reducing conditions (.140 to .190 mV) generally prevail in the investigated groundwaters. This is in line with measured Eh values in brackish marine waters of Littorina type from the site investigations in Forsmark and Laxemar (PLU). Hydrogeochemical observations together with palaeoclimatic considerations were used to differentiate the groundwaters into four major types; 1) local Baltic Sea water type, 2) Littorina type water with a glacial component, 3) brackish glacial water type, and 4) mixed brackish water (transition type). Explorative analyses using traditional geochemical approaches have been performed to describe groundwater conditions (origin and evolution) and other properties (mixing and reactions) in more detail. The division into groundwater types has facilitated interaction and integration with the hydrogeological models making it possible to construct a hydrogeochemical site descriptive model for the SFR site. The distribution of the different groundwater types shows that the major deformation zones have served as important groundwater flow pathways over long periods of geological time while single fractures in rock volumes between zones generally contain older and more isolated groundwater. Presently, the steeply dipping structures in particular have facilitated the drawdown of modern Baltic Sea water which has been observed since excavation and construction of the SFR some twenty years ago. Understanding the evolution of the groundwater system over time, i.e. since the last glaciation and more recently since excavation and construction of the SFR repository, shows that: 1) present-day hydraulic conditions have preserved groundwater patterns which replicate to a large extent what will occur during the next deglaciation (long-term perspective), and 2) the future impact of extended excavations and underground construction on groundwater chemistry can be predicted from past

  19. Large-scale spatial distribution patterns of gastropod assemblages in rocky shores.

    Directory of Open Access Journals (Sweden)

    Patricia Miloslavich

    Full Text Available Gastropod assemblages from nearshore rocky habitats were studied over large spatial scales to (1 describe broad-scale patterns in assemblage composition, including patterns by feeding modes, (2 identify latitudinal pattern of biodiversity, i.e., richness and abundance of gastropods and/or regional hotspots, and (3 identify potential environmental and anthropogenic drivers of these assemblages. Gastropods were sampled from 45 sites distributed within 12 Large Marine Ecosystem regions (LME following the NaGISA (Natural Geography in Shore Areas standard protocol (www.nagisa.coml.org. A total of 393 gastropod taxa from 87 families were collected. Eight of these families (9.2% appeared in four or more different LMEs. Among these, the Littorinidae was the most widely distributed (8 LMEs followed by the Trochidae and the Columbellidae (6 LMEs. In all regions, assemblages were dominated by few species, the most diverse and abundant of which were herbivores. No latitudinal gradients were evident in relation to species richness or densities among sampling sites. Highest diversity was found in the Mediterranean and in the Gulf of Alaska, while highest densities were found at different latitudes and represented by few species within one genus (e.g. Afrolittorina in the Agulhas Current, Littorina in the Scotian Shelf, and Lacuna in the Gulf of Alaska. No significant correlation was found between species composition and environmental variables (r≤0.355, p>0.05. Contributing variables to this low correlation included invasive species, inorganic pollution, SST anomalies, and chlorophyll-a anomalies. Despite data limitations in this study which restrict conclusions in a global context, this work represents the first effort to sample gastropod biodiversity on rocky shores using a standardized protocol across a wide scale. Our results will generate more work to build global databases allowing for large-scale diversity comparisons of rocky intertidal assemblages.

  20. The effect of multiple paternity on genetic diversity of small populations during and after colonisation.

    Directory of Open Access Journals (Sweden)

    Marina Rafajlović

    Full Text Available Genetic variation within and among populations is influenced by the genetic content of the founders and the migrants following establishment. This is particularly true if populations are small, migration rate low and habitats arranged in a stepping-stone fashion. Under these circumstances the level of multiple paternity is critical since multiply mated females bring more genetic variation into founder groups than single mated females. One such example is the marine snail Littorina saxatilis that during postglacial times has invaded mainland refuge areas and thereafter small islands emerging due to isostatic uplift by occasional rafting of multiply mated females. We modelled effects of varying degrees of multiple paternity on the genetic variation of island populations colonised by the founders spreading from the mainland, by quantifying the population heterozygosity during both the transient colonisation process, and after a steady state (with migration has been reached. During colonisation, multiple mating by [Formula: see text] males increased the heterozygosity by [Formula: see text] in comparison with single paternity, while in the steady state the increase was [Formula: see text] compared with single paternity. In the steady state the increase of heterozygosity due to multiple paternity is determined by a corresponding increase in effective population size. During colonisation, by contrast, the increase in heterozygosity is larger and it cannot be explained in terms of the effective population size alone. During the steady-state phase bursts of high genetic variation spread through the system, and far from the mainland this led to short periods of high diversity separated by long periods of low diversity. The size of these fluctuations was boosted by multiple paternity. We conclude that following glacial periods of extirpation, recolonization of isolated habitats by this species has been supported by its high level of multiple paternity.

  1. Genome-Wide Scan for Adaptive Divergence and Association with Population-Specific Covariates.

    Science.gov (United States)

    Gautier, Mathieu

    2015-12-01

    In population genomics studies, accounting for the neutral covariance structure across population allele frequencies is critical to improve the robustness of genome-wide scan approaches. Elaborating on the BayEnv model, this study investigates several modeling extensions (i) to improve the estimation accuracy of the population covariance matrix and all the related measures, (ii) to identify significantly overly differentiated SNPs based on a calibration procedure of the XtX statistics, and (iii) to consider alternative covariate models for analyses of association with population-specific covariables. In particular, the auxiliary variable model allows one to deal with multiple testing issues and, providing the relative marker positions are available, to capture some linkage disequilibrium information. A comprehensive simulation study was carried out to evaluate the performances of these different models. Also, when compared in terms of power, robustness, and computational efficiency to five other state-of-the-art genome-scan methods (BayEnv2, BayScEnv, BayScan, flk, and lfmm), the proposed approaches proved highly effective. For illustration purposes, genotyping data on 18 French cattle breeds were analyzed, leading to the identification of 13 strong signatures of selection. Among these, four (surrounding the KITLG, KIT, EDN3, and ALB genes) contained SNPs strongly associated with the piebald coloration pattern while a fifth (surrounding PLAG1) could be associated to morphological differences across the populations. Finally, analysis of Pool-Seq data from 12 populations of Littorina saxatilis living in two different ecotypes illustrates how the proposed framework might help in addressing relevant ecological issues in nonmodel species. Overall, the proposed methods define a robust Bayesian framework to characterize adaptive genetic differentiation across populations. The BayPass program implementing the different models is available at http://www1.montpellier

  2. Increasing sea surface temperature and range shifts of intertidal gastropods along the Iberian Peninsula

    Science.gov (United States)

    Rubal, Marcos; Veiga, Puri; Cacabelos, Eva; Moreira, Juan; Sousa-Pinto, Isabel

    2013-03-01

    There are well-documented changes in abundance and geographical range of intertidal invertebrates related to climate change at north Europe. However, the effect of sea surface warming on intertidal invertebrates has been poorly studied at lower latitudes. Here we analyze potential changes in the abundance patterns and distribution range of rocky intertidal gastropods related to climate change along the Iberian Peninsula. To achieve this aim, the spatial distribution and range of sub-tropical, warm- and cold-water species of intertidal gastropods was explored by a fully hierarchical sampling design considering four different spatial scales, i.e. from region (100 s of km apart) to quadrats (ms apart). Variability on their patterns of abundance was explored by analysis of variance, changes on their distribution ranges were detected by comparing with previous records and their relationship with sea water temperature was explored by rank correlation analyses. Mean values of sea surface temperature along the Iberian coast, between 1949 and 2010, were obtained from in situ data compiled for three different grid squares: south Portugal, north Portugal, and Galicia. Lusitanian species did not show significant correlation with sea water temperature or changes on their distributional range or abundance, along the temperature gradient considered. The sub-tropical species Siphonaria pectinata has, however, increased its distribution range while boreal cold-water species showed the opposite pattern. The latter was more evident for Littorina littorea that was almost absent from the studied rocky shores of the Iberian Peninsula. Sub-tropical and boreal species showed significant but opposite correlation with sea water temperature. We hypothesized that the energetic cost of frequent exposures to sub-lethal temperatures might be responsible for these shifts. Therefore, intertidal gastropods at the Atlantic Iberian Peninsula coast are responding to the effect of global warming as it

  3. Transfer across the human gut of environmental plutonium, americium, cobalt, caesium and technetium: studies with cockles (Cerastoderma edule) from the Irish Sea

    International Nuclear Information System (INIS)

    Hunt, G.J.

    1998-01-01

    Our previous studies have indicated lower values of the gut transfer factor ('f L values') for plutonium and americium in winkles (Littorina littorea) than adopted by ICRP. The present study was undertaken primarily to investigate whether this observation extends to other species. Samples of cockles (Cerastoderma edule) from Ravenglass, Cumbria were eaten by volunteers who provided 24 samples of urine and faeces. Urine samples indicated f L values for cockles which were higher than for winkles; for plutonium these ranged overall up to 7x10 -4 with an arithmetic mean in the range (2-3)x10 -4 , and for americium up to 2.6x10 -4 with an arithmetic mean of 1.2x10 -4 . Limited data based on volunteers eating cockles from the Solway suggest that f L values for americium may be greater at distance from Sellafield. The measured values compare with 5x10 -4 used by the ICRP for environmental forms of both elements, which would appear to provide adequate protection when calculating doses from Cumbrian cockles. Data for other nuclides were obtained by analysing faecal samples from the volunteers who ate the Ravenglass cockles. Cobalt-60 showed an f L value in the region of 0.2, twice the value currently used by ICRP. For 137 Cs, variabilities were indicated in the range 0.08 to 0.43, within the ICRP value of f L =1.0. Technetium-99 gave f L values up to about 0.6, in reasonable conformity with the ICRP value of 0.5. (author)

  4. Non-linear density-dependent effects of an intertidal ecosystem engineer.

    Science.gov (United States)

    Harley, Christopher D G; O'Riley, Jaclyn L

    2011-06-01

    Ecosystem engineering is an important process in a variety of ecosystems. However, the relationship between engineer density and engineering impact remains poorly understood. We used experiments and a mathematical model to examine the role of engineer density in a rocky intertidal community in northern California. In this system, the whelk Nucella ostrina preys on barnacles (Balanus glandula and Chthamalus dalli), leaving empty barnacle tests as a resource (favorable microhabitat) for other species. Field experiments demonstrated that N. ostrina predation increased the availability of empty tests of both barnacle species, reduced the density of the competitively dominant B. glandula, and indirectly increased the density of the competitively inferior C. dalli. Empty barnacle tests altered microhabitat humidity, but not temperature, and presumably provided a refuge from wave action. The herbivorous snail Littorina plena was positively associated with empty test availability in both observational comparisons and experimental manipulations of empty test availability, and L. plena density was elevated in areas with foraging N. ostrina. To explore the effects of variation in N. ostrina predation, we constructed a demographic matrix model for barnacles in which we varied predation intensity. The model predicted that number of available empty tests increases with predation intensity to a point, but declines when predation pressure was strong enough to severely reduce adult barnacle densities. The modeled number of available empty tests therefore peaked at an intermediate level of N. ostrina predation. Non-linear relationships between engineer density and engineer impact may be a generally important attribute of systems in which engineers influence the population dynamics of the species that they manipulate.

  5. Traditional utilization and biochemical composition of six mollusc shells in Nigeria

    Directory of Open Access Journals (Sweden)

    Ademolu Kehinde O.

    2015-06-01

    Full Text Available The shells of molluscs protect them from physical damage, predators and dehydration. We studied various local uses of shells and their biochemical properties in Abeokuta, Nigeria. A standard structured questionnaire about use was applied to 100 snail and herb sellers and shells from 120 adult individuals of Archachatina marginata, Achatina achatina, Achatina fulica, Littorina littorea, Meretrix lusoria and Merceneria mercenaria were evaluated for their mineral components (Ca2+, Fe2+, Mg2+, Na+, Zn+, P+, K+ and proximate composition (crude protein, ash, fibre, crude fat and carbohydrate using standard methods. Properties against fungi and bacteria isolates were also tested. These shells are used for bleaching, brushing, abrasion and others. The weight of the shells varied from 0.5g (L. littorea to 25.00g (A. marginata and thickness from 0.46mm in M .lusoria to 5.35mm in M. mercenaria. We found no inhibitory effect against fungi and bacterial isolates. The molluscs are high in carbohydrates (83.54-92.76g/100g and low in protein (0.16-0.38g/100g. The fat content ranged between 0.42g/100g and 0.82g/100g, and ash between 2.14g/100g and 9.45g/100g. Ca2+ was the most abundant (10.25-96.35mg/g while K+ was the least abundant (0.3-0.7mg/g (p<0.05. Active ingredients of these shells can be used in the feed and construction industries.

  6. Molecular identification of marine symbiont bacteria of gastropods from the waters of the Krakal coast Yogyakarta and its potential as a Multi-Drug Resistant (MDR) antibacterial agent

    Science.gov (United States)

    Bahry, Muhammad Syaifudien; Pringgenies, Delianis; Trianto, Agus

    2017-01-01

    The resistance of pathogenic bacteria may occur to many types of antibiotics, especially in cases of non-compliance use of antibiotics, which likely to allow the evolution of Multi-Drug Resistant (MDR) bacteria. Gastropods seas are marine invertebrates informed capable of production of secondary metabolites as antibacterial MDR. The purpose of the study was the isolation and identification of gastropod symbiont bacteria found in the waters of Krakal, Gunung Kidul, Yogyakarta, which has the ability to produce antibacterial compounds against MDR(Escherichia coli, Enterobacter cloacae, Klebsiella pneumoniae, MRSA (methicillin-Resistant Staphylococcus aureus), Staphylococcus aureus, and Staphylococcus homunis) molecular. Stages of this research began with the isolation of bacteria, bacteria screening for anti-MDR compound, mass culture, and extraction, antibacterial activity test, DNA extraction, amplification by PCR 16S rDNA and sequencing. The results of the study showed that 19 isolates of bacteria were isolated from three species of gastropods namely Littorina scabra, Cypraea moneta and Conus ebraeus. Among them, 4 isolates showed activity against MDR test bacteria (E. coli, E. cloacae, K. pneumoniae, S. aureus and S. homunis). The highest activity was displayed by code LS.G1.8 isolate with the largest inhibition zone 15.47±0.45mm on S. humonis at 250 µg/disk concentration. Isolate CM.G2.1 showed largest inhibition zone, with 21.5±0.07mm on MRSA at 1000 µg/disk concentration and isolate the largest inhibition zone CM.G2.5 14.37±0.81mm on MRSA 14.37±0.81mm at concentrations 1000 µg/disk. The molecular identification of isolates LS.G1.8 has 99% homology with Bacillus subtilis and isolates CM.G2.1 has 99% homology with Bacillus pumillus.

  7. Assessment of PAHs levels in some fish and seafood from different coastal waters in the Niger Delta

    Directory of Open Access Journals (Sweden)

    E.O. Nwaichi

    Full Text Available Levels of sixteen polycyclic aromatic hydrocarbons (PAHs in 30 edible tissues of selected frequently-consumed fish and seafood collected from three coastal waters of Niger Delta, namely, Sime, Kporghor and Iko were investigated in 2014. Gas chromatographic analysis were employed for PAHs determination. Observed mean PAHs levels in the samples ranged from below detection limit (BD of analytical instrument to 22.400 ± 0.050 μg kg−1 wet wt. in Littorina littorea, BD to 87.400 ± 0.030 μg kg−1 wet wt. in Crassostrea virginica and from BD to 171.000 ± 0.430 μg kg−1 wet wt. in Periophthalmus koeleuteri. The highest average concentration of 171.000 ± 0.430 μg kg−1 wet wt. was recorded for Indeno [1,2,3-cd]pyrene from Sime water. High molecular weight PAHs (HMW-PAHs were generally predominant compared to low molecular weight PAHs (LMW-PAHs. The LMW- PAH/HMW-PAH ratio was <1 for all species, indicating anthropogenic origin of PAHs in the coastal waters of Niger Delta environment. Moreover, the study of the PAHs fingerprints, using specific ratios, suggests the predominance of a pyrolytic origin for observed PAHs. Keywords: Organic contaminants, LMW- PAH/HMW-PAH ratio, Nigerian waters, Bioaccumulation, Exposure, Water pollution, Specialty: Safety issues, Water pollution, Bioaccumulation

  8. The Effect of Multiple Paternity on Genetic Diversity of Small Populations during and after Colonisation

    KAUST Repository

    Rafajlović, Marina

    2013-10-28

    Genetic variation within and among populations is influenced by the genetic content of the founders and the migrants following establishment. This is particularly true if populations are small, migration rate low and habitats arranged in a stepping-stone fashion. Under these circumstances the level of multiple paternity is critical since multiply mated females bring more genetic variation into founder groups than single mated females. One such example is the marine snail Littorina saxatilis that during postglacial times has invaded mainland refuge areas and thereafter small islands emerging due to isostatic uplift by occasional rafting of multiply mated females. We modelled effects of varying degrees of multiple paternity on the genetic variation of island populations colonised by the founders spreading from the mainland, by quantifying the population heterozygosity during both the transient colonisation process, and after a steady state (with migration) has been reached. During colonisation, multiple mating by 2-10 males increased the heterozygosity by 10-300% in comparison with single paternity, while in the steady state the increase was 10-50% compared with single paternity. In the steady state the increase of heterozygosity due to multiple paternity is determined by a corresponding increase in effective population size. During colonisation, by contrast, the increase in heterozygosity is larger and it cannot be explained in terms of the effective population size alone. During the steady-state phase bursts of high genetic variation spread through the system, and far from the mainland this led to short periods of high diversity separated by long periods of low diversity. The size of these fluctuations was boosted by multiple paternity. We conclude that following glacial periods of extirpation, recolonization of isolated habitats by this species has been supported by its high level of multiple paternity. 2013 Rafajlovi? et al.

  9. Mycoplasmas, plants, insect vectors: a matrimonial triangle.

    Science.gov (United States)

    Garnier, M; Foissac, X; Gaurivaud, P; Laigret, F; Renaudin, J; Saillard, C; Bové, J M

    2001-10-01

    Plant pathogenic mycoplasmas were discovered by electron microscopy, in 1967, long after the discovery and culture in 1898 of the first pathogenic mycoplasma of animal origin, Mycoplasma mycoides. Mycoplasmas are Eubacteria of the class Mollicutes, a group of organisms phylogenetically related to Gram-positive bacteria. Their more characteristic features reside in the small size of their genomes, the low guanine (G) plus cytosine (C) content of their genomic DNA and the lack of a cell wall. Plant pathogenic mycoplasmas are responsible for several hundred diseases and belong to two groups: the phytoplasmas and the spiroplasmas. The phytoplasmas (previously called MLOs, for mycoplasma like organisms) were discovered first; they are pleiomorphic, and have so far resisted in vitro cultivation. Phytoplasmas represent the largest group of plant pathogenic Mollicutes. Only three plant pathogenic spiroplasmas are known today. Spiroplasma citri, the agent of citrus stubborn was discovered and cultured in 1970 and shown to be helical and motile. S. kunkelii is the causal agent of corn stunt. S. phoeniceum, responsible for periwinkle yellows, was discovered in Syria. There are many other spiroplasmas associated with insects and ticks. Plant pathogenic mycoplasmas are restricted to the phloem sieve tubes in which circulates the photosynthetically-enriched sap, the food for many phloem-feeding insects (aphids, leafhoppers, psyllids, etc.). Interestingly, phytopathogenic mycoplasmas are very specifically transmitted by leafhoppers or psyllid species. In this paper, the most recent knowledge on phytopathogenic mycoplasmas in relation with their insect and plant habitats is presented as well as the experiments carried out to control plant mycoplasma diseases, by expression of mycoplasma-directed-antibodies in plants (plantibodies).

  10. Evaluation of phytoremediation of petroleum hydrocarbon and heavy metals with using Catharanthus roseus

    Directory of Open Access Journals (Sweden)

    Mehri Askary Mehrabadi

    2014-08-01

    Full Text Available Crude oil pollution is an inevitable worldwide phenomenon in oil producing and consuming areas that stems from human error, accidental discharge and other sources. The aim of this study was to evaluate the phytoremediation potential of vinca in petroleum-polluted soil. The experiment was laid out as a completely randomized design in 3 replications with different concentrations of crude oil (0, 0.5, 1, 2, 3 and 4 % V/W in pot planting stage. At the end of the 70-day period, soil samples were analyzed for total hydrocarbons removal. Contents of pb, zn and Ni were measured by atomic absorption from the soils and the leaves. Statistical analysis of data were performed on the basis of duncan’s test and by using of SPSS16 software. In concentrations higher than 3 % no growth was observed. The growth parameters such as stem length, stem fresh and dry matter decreased progressively from 0.5-3 % crude oil in soil. The results showed heavy metal accumulation in plant leaves and reduction of them in the soil. Heavy metals containing zinc, lead and nickel in plant increased in different concentration of crude oil. Total hydrocarbons and heavy metals containing zinc, lead and nickel reduced were in planted contaminated soil. This study showed that Periwinkle was able to grow and survive in low concentrations of oil and reduced pollutants in the soil. Based upon these results, Catharanthus roseus can be used as phytoremediator of petroleum-contaminated soil in low concentrations.

  11. Metals in the Scheldt estuary: From environmental concentrations to bioaccumulation.

    Science.gov (United States)

    Van Ael, Evy; Blust, Ronny; Bervoets, Lieven

    2017-09-01

    To investigate the relationship between metal concentrations in abiotic compartments and in aquatic species, sediment, suspended matter and several aquatic species (Polychaeta, Oligochaeta, four crustacean species, three mollusc species and eight fish species) were collected during three seasons at six locations along the Scheldt estuary (the Netherlands-Belgium) and analysed on their metal content (Ag, Cd, Co, Cr, Cu, Ni, Pb, Zn and the metalloid As). Sediment and biota tissue concentrations were significantly influenced by sampling location, but not by season. Measurements of Acid Volatile Sulphides (AVS) concentrations in relation to Simultaneously Extracted Metals (SEM) in the sediment suggested that not all metals in the sediment will be bound to sulphides and some metals might be bioavailable. For all metals but zinc, highest concentrations were measured in invertebrate species; Ag and Ni in periwinkle, Cr, Co and Pb in Oligochaete worms and As, Cd and Cu in crabs and shrimp. Highest concentrations of Zn were measured in the kidney of European smelt. In fish, for most of the metals, the concentrations were highest in liver or kidney and lowest in muscle. For Zn however, highest concentrations were measured in the kidney of European smelt. For less than half of the metals significant correlations between sediment metal concentrations and bioaccumulated concentrations were found (liver/hepatopancreas or whole organism). To calculate the possible human health risk by consumption, average and maximum metal concentrations in the muscle tissues were compared to the minimum risk levels (MRLs). Concentrations of As led to the highest risk potential for all consumable species. Cadmium and Cu posed only a risk when consuming the highest contaminated shrimp and shore crabs. Consuming blue mussel could result in a risk for the metals As, Cd and Cr. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Botanical Provenance of Traditional Medicines From Carpathian Mountains at the Ukrainian-Polish Border.

    Science.gov (United States)

    Kozlowska, Weronika; Wagner, Charles; Moore, Erin M; Matkowski, Adam; Komarnytsky, Slavko

    2018-01-01

    Plants were an essential part of foraging for food and health, and for centuries remained the only medicines available to people from the remote mountain regions. Their correct botanical provenance is an essential basis for understanding the ethnic cultures, as well as for chemical identification of the novel bioactive molecules with therapeutic effects. This work describes the use of herbal medicines in the Beskid mountain ranges located south of Krakow and Lviv, two influential medieval centers of apothecary tradition in the region. Local botanical remedies shared by Boyko, Lemko, and Gorale ethnic groups were a part of the medieval European system of medicine, used according to their Dioscoridean and Galenic qualities. Within the context of ethnic plant medicine and botanical classification, this review identified strong preferences for local use of St John's-wort ( Hypericum perforatum L.), wormwood ( Artemisia absinthium L.), garlic ( Allium sativum L.), gentian ( Gentiana lutea L.), lovage ( Levisticum officinale W.D.J. Koch), and lesser periwinkle ( Vinca minor L.). While Ukrainian ethnic groups favored the use of guilder-rose ( Viburnum opulus L.) and yarrow ( Achillea millefolium L.), Polish inhabitants especially valued angelica ( Angelica archangelica L.) and carline thistle ( Carlina acaulis L.). The region also holds a strong potential for collection, cultivation, and manufacture of medicinal plants and plant-based natural specialty ingredients for the food, health and cosmetic industries, in part due to high degree of biodiversity and ecological preservation. Many of these products, including whole food nutritional supplements, will soon complement conventional medicines in prevention and treatment of diseases, while adding value to agriculture and local economies.

  13. Botanical Provenance of Traditional Medicines From Carpathian Mountains at the Ukrainian-Polish Border

    Directory of Open Access Journals (Sweden)

    Weronika Kozlowska

    2018-04-01

    Full Text Available Plants were an essential part of foraging for food and health, and for centuries remained the only medicines available to people from the remote mountain regions. Their correct botanical provenance is an essential basis for understanding the ethnic cultures, as well as for chemical identification of the novel bioactive molecules with therapeutic effects. This work describes the use of herbal medicines in the Beskid mountain ranges located south of Krakow and Lviv, two influential medieval centers of apothecary tradition in the region. Local botanical remedies shared by Boyko, Lemko, and Gorale ethnic groups were a part of the medieval European system of medicine, used according to their Dioscoridean and Galenic qualities. Within the context of ethnic plant medicine and botanical classification, this review identified strong preferences for local use of St John's-wort (Hypericum perforatum L., wormwood (Artemisia absinthium L., garlic (Allium sativum L., gentian (Gentiana lutea L., lovage (Levisticum officinale W.D.J. Koch, and lesser periwinkle (Vinca minor L.. While Ukrainian ethnic groups favored the use of guilder-rose (Viburnum opulus L. and yarrow (Achillea millefolium L., Polish inhabitants especially valued angelica (Angelica archangelica L. and carline thistle (Carlina acaulis L.. The region also holds a strong potential for collection, cultivation, and manufacture of medicinal plants and plant-based natural specialty ingredients for the food, health and cosmetic industries, in part due to high degree of biodiversity and ecological preservation. Many of these products, including whole food nutritional supplements, will soon complement conventional medicines in prevention and treatment of diseases, while adding value to agriculture and local economies.

  14. Cold-stenothermic spring fauna in mountainous headwaters of the National Park Kellerwald-Edersee in Germany

    Science.gov (United States)

    Reiss, Martin; Zaenker, Stefan; Chifflard, Peter

    2017-04-01

    ,9). Due to nearly unaffected ecohydrological properties, in particular: relative consistently cold water temperature with low amplitudes (cold stenothermy), mostly low flow velocity and an intermittent discharge regime a very unique and specific adapted spring fauna composition for the German low mountain ranges can be characterized. Cold stenothermic and spring related species are very frequent in relative occurrence and abundance. We analyzed a map based and representative distribution for the entire large-scale protected area of the National Park Kellerwald-Edersee according to Bythinella dunkeri (spring snail), Crenobia alpina (planarian), Crunoecia irrorata (caddisfly) and Niphargus schellenbergi (groundwater amphipod). We discuss the potential of ecohydrological research on possible climate change predictions and consequences on the distribution of cold stenothermic and spring dwelling species within the special context of research goals in National Parks. Here, an idea of a new approach for an ecohydrological assessment by indicating cold stenothermic taxa is given as an outlook. References Reiss, M., Steiner, H. & S. Zaenker (2009): The Biospeleological Register of the Hesse Federation for Cave and Karst Research (Germany). Cave and Karst Science 35(1), pp.25-34.

  15. Reconstructing Holocene temperature and salinity variations in the western Baltic Sea region: a multi-proxy comparison from the Little Belt (IODP Expedition 347, Site M0059)

    Science.gov (United States)

    Kotthoff, Ulrich; Groeneveld, Jeroen; Ash, Jeanine L.; Fanget, Anne-Sophie; Quintana Krupinski, Nadine; Peyron, Odile; Stepanova, Anna; Warnock, Jonathan; Van Helmond, Niels A. G. M.; Passey, Benjamin H.; Rønø Clausen, Ole; Bennike, Ole; Andrén, Elinor; Granoszewski, Wojciech; Andrén, Thomas; Filipsson, Helena L.; Seidenkrantz, Marit-Solveig; Slomp, Caroline P.; Bauersachs, Thorsten

    2017-12-01

    Sediment records recovered from the Baltic Sea during Integrated Ocean Drilling Program Expedition 347 provide a unique opportunity to study paleoenvironmental and climate change in central and northern Europe. Such studies contribute to a better understanding of how environmental parameters change in continental shelf seas and enclosed basins. Here we present a multi-proxy-based reconstruction of paleotemperature (both marine and terrestrial), paleosalinity, and paleoecosystem changes from the Little Belt (Site M0059) over the past ˜ 8000 years and evaluate the applicability of inorganic- and organic-based proxies in this particular setting. All salinity proxies (diatoms, aquatic palynomorphs, ostracods, diol index) show that lacustrine conditions occurred in the Little Belt until ˜ 7400 cal yr BP. A connection to the Kattegat at this time can thus be excluded, but a direct connection to the Baltic Proper may have existed. The transition to the brackish-marine conditions of the Littorina Sea stage (more saline and warmer) occurred within ˜ 200 years when the connection to the Kattegat became established after ˜ 7400 cal yr BP. The different salinity proxies used here generally show similar trends in relative changes in salinity, but often do not allow quantitative estimates of salinity. The reconstruction of water temperatures is associated with particularly large uncertainties and variations in absolute values by up to 8 °C for bottom waters and up to 16 °C for surface waters. Concerning the reconstruction of temperature using foraminiferal Mg  /  Ca ratios, contamination by authigenic coatings in the deeper intervals may have led to an overestimation of temperatures. Differences in results based on the lipid paleothermometers (long chain diol index and TEXL86) can partly be explained by the application of modern-day proxy calibrations to intervals that experienced significant changes in depositional settings: in the case of our study, the change from

  16. Reconstructing Holocene temperature and salinity variations in the western Baltic Sea region: a multi-proxy comparison from the Little Belt (IODP Expedition 347, Site M0059

    Directory of Open Access Journals (Sweden)

    U. Kotthoff

    2017-12-01

    Full Text Available Sediment records recovered from the Baltic Sea during Integrated Ocean Drilling Program Expedition 347 provide a unique opportunity to study paleoenvironmental and climate change in central and northern Europe. Such studies contribute to a better understanding of how environmental parameters change in continental shelf seas and enclosed basins. Here we present a multi-proxy-based reconstruction of paleotemperature (both marine and terrestrial, paleosalinity, and paleoecosystem changes from the Little Belt (Site M0059 over the past  ∼  8000 years and evaluate the applicability of inorganic- and organic-based proxies in this particular setting. All salinity proxies (diatoms, aquatic palynomorphs, ostracods, diol index show that lacustrine conditions occurred in the Little Belt until  ∼  7400 cal yr BP. A connection to the Kattegat at this time can thus be excluded, but a direct connection to the Baltic Proper may have existed. The transition to the brackish–marine conditions of the Littorina Sea stage (more saline and warmer occurred within  ∼  200 years when the connection to the Kattegat became established after  ∼  7400 cal yr BP. The different salinity proxies used here generally show similar trends in relative changes in salinity, but often do not allow quantitative estimates of salinity. The reconstruction of water temperatures is associated with particularly large uncertainties and variations in absolute values by up to 8 °C for bottom waters and up to 16 °C for surface waters. Concerning the reconstruction of temperature using foraminiferal Mg  /  Ca ratios, contamination by authigenic coatings in the deeper intervals may have led to an overestimation of temperatures. Differences in results based on the lipid paleothermometers (long chain diol index and TEXL86 can partly be explained by the application of modern-day proxy calibrations to intervals that experienced significant

  17. Natural Competence of Xylella fastidiosa Occurs at a High Frequency Inside Microfluidic Chambers Mimicking the Bacterium's Natural Habitats.

    Science.gov (United States)

    Kandel, Prem P; Lopez, Samantha M; Almeida, Rodrigo P P; De La Fuente, Leonardo

    2016-09-01

    Xylella fastidiosa is a xylem-limited bacterium that is the causal agent of emerging diseases in a number of economically important crops. Genetic diversity studies have demonstrated homologous recombination occurring among X. fastidiosa strains, which has been proposed to contribute to host plant shifts. Moreover, experimental evidence confirmed that X. fastidiosa is naturally competent for recombination in vitro Here, as an approximation of natural habitats (plant xylem vessels and insect mouthparts), recombination was studied in microfluidic chambers (MCs) filled with media amended with grapevine xylem sap. First, different media were screened for recombination in solid agar plates using a pair of X. fastidiosa strains that were previously reported to recombine in coculture. The highest frequency of recombination was obtained with PD3 medium, compared to those with the other two media (X. fastidiosa medium [XFM] and periwinkle wilt [PW] medium) used in previous studies. Dissection of the media components led to the identification of bovine serum albumin as an inhibitor of recombination that was correlated to its previously known effect on inhibition of twitching motility. When recombination was performed in liquid culture, the frequencies were significantly higher under flow conditions (MCs) than under batch conditions (test tubes). The recombination frequencies in MCs and agar plates were not significantly different from each other. Grapevine xylem sap from both susceptible and tolerant varieties allowed high recombination frequency in MCs when mixed with PD3. These results suggest that X. fastidiosa has the ability to be naturally competent in the natural growth environment of liquid flow, and this phenomenon could have implications in X. fastidiosa environmental adaptation. Xylella fastidiosa is a plant pathogen that lives inside xylem vessels (where water and nutrients are transported inside the plant) and the mouthparts of insect vectors. This bacterium

  18. Sex- and habitat-specific movement of an omnivorous semi-terrestrial crab controls habitat connectivity and subsidies: a multi-parameter approach.

    Science.gov (United States)

    Hübner, Lena; Pennings, Steven C; Zimmer, Martin

    2015-08-01

    Distinct habitats are often linked through fluxes of matter and migration of organisms. In particular, intertidal ecotones are prone to being influenced from both the marine and the terrestrial realms, but whether or not small-scale migration for feeding, sheltering or reproducing is detectable may depend on the parameter studied. Within the ecotone of an upper saltmarsh in the United States, we investigated the sex-specific movement of the semi-terrestrial crab Armases cinereum using an approach of determining multiple measures of across-ecotone migration. To this end, we determined food preference, digestive abilities (enzyme activities), bacterial hindgut communities (genetic fingerprint), and the trophic position of Armases and potential food sources (stable isotopes) of males versus females of different sub-habitats, namely high saltmarsh and coastal forest. Daily observations showed that Armases moved frequently between high-intertidal (saltmarsh) and terrestrial (forest) habitats. Males were encountered more often in the forest habitat, whilst gravid females tended to be more abundant in the marsh habitat but moved more frequently. Food preference was driven by both sex and habitat. The needlerush Juncus was preferred over three other high-marsh detrital food sources, and the periwinkle Littoraria was the preferred prey of male (but not female) crabs from the forest habitats; both male and female crabs from marsh habitat preferred the fiddler crab Uca over three other prey items. In the field, the major food sources were clearly vegetal, but males have a higher trophic position than females. In contrast to food preference, isotope data excluded Uca and Littoraria as major food sources, except for males from the forest, and suggested that Armases consumes a mix of C4 and C3 plants along with animal prey. Digestive enzyme activities differed significantly between sexes and habitats and were higher in females and in marsh crabs. The bacterial hindgut community

  19. Metals in the Scheldt estuary: From environmental concentrations to bioaccumulation

    International Nuclear Information System (INIS)

    Van Ael, Evy; Blust, Ronny; Bervoets, Lieven

    2017-01-01

    To investigate the relationship between metal concentrations in abiotic compartments and in aquatic species, sediment, suspended matter and several aquatic species (Polychaeta, Oligochaeta, four crustacean species, three mollusc species and eight fish species) were collected during three seasons at six locations along the Scheldt estuary (the Netherlands-Belgium) and analysed on their metal content (Ag, Cd, Co, Cr, Cu, Ni, Pb, Zn and the metalloid As). Sediment and biota tissue concentrations were significantly influenced by sampling location, but not by season. Measurements of Acid Volatile Sulphides (AVS) concentrations in relation to Simultaneously Extracted Metals (SEM) in the sediment suggested that not all metals in the sediment will be bound to sulphides and some metals might be bioavailable. For all metals but zinc, highest concentrations were measured in invertebrate species; Ag and Ni in periwinkle, Cr, Co and Pb in Oligochaete worms and As, Cd and Cu in crabs and shrimp. Highest concentrations of Zn were measured in the kidney of European smelt. In fish, for most of the metals, the concentrations were highest in liver or kidney and lowest in muscle. For Zn however, highest concentrations were measured in the kidney of European smelt. For less than half of the metals significant correlations between sediment metal concentrations and bioaccumulated concentrations were found (liver/hepatopancreas or whole organism). To calculate the possible human health risk by consumption, average and maximum metal concentrations in the muscle tissues were compared to the minimum risk levels (MRLs). Concentrations of As led to the highest risk potential for all consumable species. Cadmium and Cu posed only a risk when consuming the highest contaminated shrimp and shore crabs. Consuming blue mussel could result in a risk for the metals As, Cd and Cr. - Highlights: • This is the first study investigating metal distribution along the aquatic ecosystem of the Scheldt

  20. Development of efficient catharanthus roseus regeneration and transformation system using agrobacterium tumefaciens and hypocotyls as explants

    Directory of Open Access Journals (Sweden)

    Wang Quan

    2012-06-01

    Full Text Available Abstract Background As a valuable medicinal plant, Madagascar periwinkle (Catharanthus roseus produces many terpenoid indole alkaloids (TIAs, such as vindoline, ajamlicine, serpentine, catharanthine, vinblastine and vincristine et al. Some of them are important components of drugs treating cancer and hypertension. However, the yields of these TIAs are low in wild-type plants, and the total chemical synthesis is impractical in large scale due to high-cost and their complicated structures. The recent development of metabolic engineering strategy offers a promising solution. In order to improve the production of TIAs in C. roseus, the establishment of an efficient genetic transformation method is required. Results To develop a genetic transformation method for C. roseus, Agrobacterium tumefaciens strain EHA105 was employed which harbors a binary vector pCAMBIA2301 containing a report β-glucuronidase (GUS gene and a selectable marker neomycin phosphotransferase II gene (NTPII. The influential factors were investigated systematically and the optimal transformation condition was achieved using hypocotyls as explants, including the sonication treatment of 10 min with 80 W, A. tumefaciens infection of 30 min and co-cultivation of 2 d in 1/2 MS medium containing 100 μM acetosyringone. With a series of selection in callus, shoot and root inducing kanamycin-containing resistance media, we successfully obtained stable transgenic regeneration plants. The expression of GUS gene was confirmed by histochemistry, polymerase chain reaction, and genomic southern blot analysis. To prove the efficiency of the established genetic transformation system, the rate-limiting gene in TIAs biosynthetic pathway, DAT, which encodes deacetylvindoline-4-O-acetyltransferase, was transferred into C. roseus using this established system and 9 independent transgenic plants were obtained. The results of metabolite analysis using high performance liquid chromatography (HPLC

  1. [Fish and seafood as a source of human exposure to methylmercury].

    Science.gov (United States)

    Mania, Monika; Wojciechowska-Mazurek, Maria; Starska, Krystyna; Rebeniak, Małgorzata; Postupolski, Jacek

    2012-01-01

    (RASFF) concerning the contamination of fish and fish products with total mercury. European and national regulations concerning maximum permissible levels of mercury in food were also presented. Possibility of selection of different fish and seafood species, taking into account low methylmercury contamination and high contents of omega-3 fatty acids e.g. sardine, mackerel, anchovy, salmon, periwinkle, have been discussed.

  2. Cellulase and Xylanase Production from Three Isolates of Indigenous Endophytic Fungi

    Science.gov (United States)

    Yopi; Tasia, W.; Melliawati, R.

    2017-12-01

    Cellulases and hemicellulases have good potential to be used in energy production, in pulp, paper, textile industries, as well as in animal feed industries. Moreover, its utilization in food industries also cannot be ignored, among others, cellulase and xylanase roles in bakery, wine, and fruit and vegetables juice production. One of the potential enzyme source is endophytic fungi. Object of this study is to explore the potency of endophytic fungi isolated from medicinal plants as source of cellulolytic and xylanolytic enzymes. HL.47F.216 is endophytic fungi isolated from traditional medicinal plants ironwood tree was determined as xylanase producer. HL.51F.235 from pin-flower tree is cellulase producer, while CBN.6F.29 which produces both xylanase and cellulase is originated from Madagascar periwinkle. HL.47F.216 showed 2.5 cm in clear zone diameter and its xylanase activity was 0.262 U/mL with optimum condition pH 7 at 50°C. HL.51F.235 showed 2.4 cm clear zone diameter and 0.239 U/mL of cellulase activity at pH 5 and 70°C. CBN.6F.29 showed 2.8 cm and 0.394 U/mL (pH 5, 40°C) for its cellulase activity, while 2.3 cm and 0.439 U/mL (pH 8, 70°C) for its xylanase activity. Xylanase from HL.47F.216 and CBN.6F.29 showed low molecular masses of 20 kDa and 37-50 kDa, respectively. Molecular masses for cellulases from HL.51F.235 and CBN.6F.29 were 25 and 50 kDa for HL.51F.235 and 100 kDa for CBN.6F.29. Based on macroscopic and microscopic identification, fungal isolate CBN.6F.29 is a member of Class Coelomycetes, while HL.47F.216 was Acremonium sp. and HL.51F.235 was Aspergillus nigri.

  3. SR-Site - hydrogeochemical evolution of the Forsmark site

    International Nuclear Information System (INIS)

    Salas, Joaquin; Molinero, Jorge; Juarez, Iker; Gimeno, Maria Jose; Auque, Luis; Gomez, Javier

    2010-12-01

    The present work has involved the development of a methodology in order to simulate the evolution of the groundwater composition within the candidate repository site of the Forsmark area. A series of climate periods is expected to be probable after the repository closure (temperate, periglacial and glacial) and, eventually, the area could be submerged under seawaters or under a lake of glacial melt waters. These environmental conditions will affect groundwater flow and composition around of the candidate repository volume. The present report summarizes the results obtained by the calculations which reproduce the hydrogeochemical evolution in the Forsmark area, and within the candidate repository volume. The hydrogeochemical evolution of groundwaters is one of the key factors affecting the chemical stability of the buffer and the canister. In this way, the main objective of the hydrogeochemical simulations is to assay the evolution of a series of safety assessment factors, such as salinity, redox potential, pH, and concentrations of iron, sulphide and potassium, among others. Using ConnectFlow, previous hydrological calculations have provided the transport of (1) the fractions of selected reference waters (Deep Saline, Old Meteoric, Glacial, Littorina and Altered Meteoric groundwaters), or (2) salinities, depending on the working team (Serco or Terrasolve). The results of the regional-scale groundwater flow modelling for each specific climate period are used as input of the geochemical models. Groundwater compositions have been modelled using PHREEQC, through mixing and chemical reactions between the waters obtained from the hydrogeological models and the reactive fracture-filling minerals. Both models (hydrological and geochemical) are not fully coupled, and it allows a description of the geochemical heterogeneity, which otherwise would be hard to attain. The stage of the open repository has been non-numerically analysed. Aspects as salinity, redox conditions

  4. Water-rock interaction modelling and uncertainties of mixing modelling. SDM-Site Laxemar

    International Nuclear Information System (INIS)

    Gimeno, Maria J.; Auque, Luis F.; Gomez, Javier B.; Acero, Patricia

    2009-01-01

    , hydrogeochemistry, microbiology, geomicrobiology, analytical chemistry etc. The resulting site descriptive model version, mainly based on available primary data from the extended data freeze L2.3 at Laxemar (November 30 2007). The data interpretation was carried out during November 2007 to September 2008. Several groups within ChemNet were involved and the evaluation was conducted independently using different approaches ranging from expert knowledge to geochemical and mathematical modelling including transport modelling. During regular ChemNet meetings the results have been presented and discussed. The original works by the ChemNet modellers are presented in four level III reports containing complementary information for the bedrock hydrogeochemistry Laxemar Site Descriptive Model (SDM-Site Laxemar, R-08-93) level II report. There is also a fifth level III report: Fracture mineralogy of the Laxemar area (R-08-99). This report presents the modelling work performed by the UZ (Univ. of Zaragoza) group as part of the work plan for Laxemar-Simpevarp 2.2 and 2.3. The main processes determining the global geochemical evolution of the Laxemar-Simpevarp groundwaters system are mixing and reaction processes. Mixing has taken place between different types of waters (end members) over time, making the discrimination of the main influences not always straightforward. Several lines of evidence suggest the input of dilute waters (cold or warm), at different stages, into a bedrock with pre-existing very saline groundwaters. Subsequently, marine water entered the system over the Littorina period (when the topography and the distance to the coast allowed it) and mixed with pre-existent groundwaters of variable salinity. In the Laxemar subarea mainland, the Littorina input occurred only locally and it has mostly been flushed out by the subsequent input of warm meteoric waters with a distinctive modern isotopic signature. In addition to mixing processes and superimposed to their effects, different

  5. Zonação de comunidade bêntica do entremarés em molhes sob diferente hidrodinamismo na costa norte do estado do Rio de Janeiro, Brasil Zonation of intertidal benthic communities on breakwaters of different hydrodynamics in the north coast of the state of Rio de Janeiro, Brazil

    Directory of Open Access Journals (Sweden)

    Bruno P. Masi

    2008-12-01

    Full Text Available O presente estudo pretende comparar a distribuição vertical da comunidade bêntica na zona entremarés em dois locais compostos por matacões graníticos caracterizados por hidrodinâmica distinta, reflexo da diferença na orientação dos molhes nas praias do Farol de São Tomé (Píer e na Barra do Furado (Barra, norte do Estado do Rio de Janeiro. Quadrados de 400 cm² foram sobrepostos ao longo de três perfis verticais de ambos os sítios e amostrados através do método de fotoquadrats, desde o nível 0,2 m da maré até o limite superior de Littorina spp. O limite superior dos organismos marinhos foi ampliado na Barra (3,8 m em relação ao Píer (2,2 m. Quanto à composição taxonômica, nove espécies foram comuns. Chaetomorpha sp., Chondracanthus teedii (Mertens ex Roth Fredericq e Grateloupia sp. foram exclusivas na Barra, enquanto Tetraclita stalactifera (Lamarck, 1818, Fissurella clench, Gracilaria domingensis (Kützing Sonder ex Dickie e Hypnea musciformis (Wulfen in Jacqu. Lamouroux ocorreram somente no Píer. Em ambos os locais, a riqueza e a diversidade de espécies foram superiores nos quadrados intermediários. Os maiores valores foram registrados na Barra. As maiores diferenças nos agrupamentos entre faixas equivalentes de locais distintos ocorreram na faixa eulitorânea superior, seguida pela faixa eulitorânea inferior e franja sublitorânea. Apenas a orla litorânea não revelou diferença significativa entre os locais, mas uma maior extensão desta franja e da faixa eulitorânea superior era bastante evidente. As demais faixas na Barra do Furado foram caracterizadas em grande parte por espécies típicas de ambientes mais expostos como Chaetomorpha sp. na faixa eulitorânea superior e Perna perna (Linnaeus, 1758 na eulitorânea inferior, além de C. teedii e Ulva fasciata Delile, 1813 na franja sublitorânea. No Píer, as diferentes faixas apresentavam distribuição eqüitativa, refletindo um ambiente menos

  6. Water-rock interaction modelling and uncertainties of mixing modelling. SDM-Site Laxemar

    Energy Technology Data Exchange (ETDEWEB)

    Gimeno, Maria J.; Auque, Luis F.; Gomez, Javier B.; Acero, Patricia (Univ. of Zaragoza, Zaragoza (Spain))

    2009-01-15

    , hydrochemistry, hydrogeochemistry, microbiology, geomicrobiology, analytical chemistry etc. The resulting site descriptive model version, mainly based on available primary data from the extended data freeze L2.3 at Laxemar (November 30 2007). The data interpretation was carried out during November 2007 to September 2008. Several groups within ChemNet were involved and the evaluation was conducted independently using different approaches ranging from expert knowledge to geochemical and mathematical modelling including transport modelling. During regular ChemNet meetings the results have been presented and discussed. The original works by the ChemNet modellers are presented in four level III reports containing complementary information for the bedrock hydrogeochemistry Laxemar Site Descriptive Model (SDM-Site Laxemar, R-08-93) level II report. There is also a fifth level III report: Fracture mineralogy of the Laxemar area (R-08-99). This report presents the modelling work performed by the UZ (Univ. of Zaragoza) group as part of the work plan for Laxemar-Simpevarp 2.2 and 2.3. The main processes determining the global geochemical evolution of the Laxemar-Simpevarp groundwaters system are mixing and reaction processes. Mixing has taken place between different types of waters (end members) over time, making the discrimination of the main influences not always straightforward. Several lines of evidence suggest the input of dilute waters (cold or warm), at different stages, into a bedrock with pre-existing very saline groundwaters. Subsequently, marine water entered the system over the Littorina period (when the topography and the distance to the coast allowed it) and mixed with pre-existent groundwaters of variable salinity. In the Laxemar subarea mainland, the Littorina input occurred only locally and it has mostly been flushed out by the subsequent input of warm meteoric waters with a distinctive modern isotopic signature. In addition to mixing processes and superimposed to their

  7. Hydrogeochemical evaluation for Simpevarp model version 1.2. Preliminary site description of the Simpevarp area

    Energy Technology Data Exchange (ETDEWEB)

    Laaksoharju, Marcus (ed.) [Geopoint AB, Stockholm (Sweden)

    2004-12-01

    shallow to intermediate (150-300 m) depths at Simpevarp, but at greater depths (approx. 900-1100 m) at Laxemar. At Simpevarp the groundwaters are mainly Na-Ca-Cl in type but some Na-Ca(Mg)-Cl(Br) types also occur. At Laxemar there is a transition to more Ca-Na-Cl types with depth. Main reactions involve weathering, ion exchange (Ca, Mg) and dissolution/precipitation of calcite. Redox reactions include precipitation of pyrite and some microbially-mediated reactions (SRB). At Simpevarp there is potentially some residual Littorina Sea (old marine) component, commonly in fracture zones close to or under the Baltic Sea. At both the Simpevarp and Laxemar sites there is a glacial component and also a deep saline (non-marine) component. TYPE C: This type comprises reducing saline groundwaters (6000-20 000 mg/L Cl; 25- 30 g/L TDS) present at intermediate to deep (>300 m) levels at Simpevarp, and at even greater depths (approx. 1200 m) at Laxemar. At Simpevarp the groundwaters are mainly Na-Ca-Cl with increasingly enhanced Br and SO{sub 4} with depth. At Laxemar they are mainly Ca-Na-Cl also with increasing enhancements of Br and SO{sub 4} with depth. Main reactions involve ion exchange (Ca). At both sites a glacial component and a deep saline component are present. At Simpevarp the saline component may be potentially non marine and/or non-marine/old Littorina marine in origin; at Laxemar it is more likely to be non-marine in origin. TYPE D: This type comprises reducing highly saline groundwaters (> 20 000 mg/L Cl; to a maximum of {approx}70 g/L TDS) and only has been identified at Laxemar at depths exceeding 1200 m. It is mainly Ca-Na-Cl with higher Br but lower SO{sub 4} compared to Type C groundwaters. Main reactions involve water/rock interaction for long residence non-marine brines driven by diffusion. A modelling approach was used to simulate the composition of the highly saline or brine groundwaters and, in the Simpevarp area, concluded that mixing is the main irreversible

  8. SR-Site - hydrogeochemical evolution of the Forsmark site

    Energy Technology Data Exchange (ETDEWEB)

    Salas, Joaquin; Molinero, Jorge; Juarez, Iker (Amphos 21 (Spain)); Gimeno, Maria Jose; Auque, Luis; Gomez, Javier (Univ. of Zaragoza (Spain))

    2010-12-15

    The present work has involved the development of a methodology in order to simulate the evolution of the groundwater composition within the candidate repository site of the Forsmark area. A series of climate periods is expected to be probable after the repository closure (temperate, periglacial and glacial) and, eventually, the area could be submerged under seawaters or under a lake of glacial melt waters. These environmental conditions will affect groundwater flow and composition around of the candidate repository volume. The present report summarizes the results obtained by the calculations which reproduce the hydrogeochemical evolution in the Forsmark area, and within the candidate repository volume. The hydrogeochemical evolution of groundwaters is one of the key factors affecting the chemical stability of the buffer and the canister. In this way, the main objective of the hydrogeochemical simulations is to assay the evolution of a series of safety assessment factors, such as salinity, redox potential, pH, and concentrations of iron, sulphide and potassium, among others. Using ConnectFlow, previous hydrological calculations have provided the transport of (1) the fractions of selected reference waters (Deep Saline, Old Meteoric, Glacial, Littorina and Altered Meteoric groundwaters), or (2) salinities, depending on the working team (Serco or Terrasolve). The results of the regional-scale groundwater flow modelling for each specific climate period are used as input of the geochemical models. Groundwater compositions have been modelled using PHREEQC, through mixing and chemical reactions between the waters obtained from the hydrogeological models and the reactive fracture-filling minerals. Both models (hydrological and geochemical) are not fully coupled, and it allows a description of the geochemical heterogeneity, which otherwise would be hard to attain. The stage of the open repository has been non-numerically analysed. Aspects as salinity, redox conditions

  9. Bacterial diversity analysis of Huanglongbing pathogen-infected citrus, using PhyloChip and 16S rRNA gene clone library sequencing

    Energy Technology Data Exchange (ETDEWEB)

    Shankar Sagaram, U.; DeAngelis, K.M.; Trivedi, P.; Andersen, G.L.; Lu, S.-E.; Wang, N.

    2009-03-01

    host plants (5,27,40). Tatineni and colleagues discovered that the HLB bacteria were unevenly distributed in phloem of bark tissue, vascular tissue of the leaf midrib, roots, and different floral and fruit parts (43). Unsuccessful attempts in culturing the pathogen are notably hampering efforts to understand its biology and pathogenesis mechanism. Using a modified Koch's Postulates approach, Jagoueix and colleagues were able to re-infect periwinkle plants from a mixed microbial community harvested from HLB diseased plants (25). Emergence of the disease in otherwise healthy plants led to the conclusion that HLB was associated with Candidatus Liberibacter sp. based on its 16S rDNA sequence (18,25). Currently, three species of the pathogen are recognized from trees with HLB disease based on 16S rDNA sequence: Ca. Liberibacter asiaticus (Las), Ca. Liberibacter africanus (Laf), and Ca. Liberibacter americanus (Lam); Las is the most prevalent species among HLB diseased trees (5,12,18,25,44). Las is naturally transmitted to citrus by the psyllid, Diaphorina citri Kuwayama, and can be artificially transmitted by grafting from citrus to citrus and dodder (Cuscuta campestris) to periwinkle (Catharanthus roseus) or tobacco (Nicotiana tabacum Xanthi) (5). Based on current research regarding the associations of Liberibacter in planta there is not enough evidence to implicate Liberibacter as the definitive causal agent of HLB disease due to its resistance to cultivation in vitro. It is possible that HLB disease may be the result of complex etiology where Liberibacter interacts with other endophytic bacteria. However, there is not enough evidence regarding its association(s) in planta to make this conclusion, nor is it known whether associated microbial communities play a role in expression of pathogenic traits. The main objective of the study was to test the hypothesis that other bacteria besides Ca. Liberibacter spp. are associated with citrus greening disease. The differences

  10. Postglacial uplift of the eastern Gulf of Finland-Lake Ladoga region: models and observations

    Science.gov (United States)

    Amantov, Aleksey; Fjeldskaar, Willy; Amantova, Marina

    2015-04-01

    The eastern Gulf of Finland - Lake Ladoga region - is at the peripheral part of the Fennoscandian post-glacial uplift. We compared different modeling results for this region with observations, including our revision of geomorphological traces of paleo shorelevel. As in many parts of the general Baltic-White Sea bedrock lowland at the margin of the Fennoscandian Shield, the bedrock landscape was modified by glaciers, but it was also the major controlling factor for the history of glacial grows and decays. First-order landforms of this segment are: Lake Ladoga-Lake Ilmen lowland, Lembolovo High of the Karelic Isthmus and Neva-Gulf of Finland lowland. The range of the bedrock topography is close to 350 m. The landforms reflect different glacial behavior during stadials, with fast movement and strong erosion in northern Ladoga, but passive motion and accumulation around Lembolovo High. The differences influenced the ice sheet and deglaciation history. The shore level displacements in this area are slightly different than westwards in the Baltic area; the shoreline tilts are usually lower in southern-central part of the eastern Gulf of Finland-lake Ladoga region. For example, the shoreline tilts at 11 600 BP in the Baltic Ice Lake in the south-east range from 0.55 to 0.31 m/km. The slope of the Ancylus shoreline varies from 0.12 to 0.18 m/km, increasing to almost the double in the north-western area. Similarly, the Littorina shore level is tilted only 0.08 m/km, rising to 0.14 m/km in the north-west. We have used this data in our high resolution modeling involving glacial isostasy, hydro isostasy, sediment isostasy, and gravity field changes. The mopdeling is based on Earth rheology model with a low-viscosity asthenosphere of thickness less than 150 km and viscosity less than 7.0x10**19 Pa s above a mantle of viscosity 10**21 Pa s, and an effective elastic lithosphere thickness of 30-40 km (flexural rigidity 10**24 Nm). The specific uplift features in the area are

  11. Estructura de la comunidad de moluscos y relaciones tróficas en el litoral rocoso del estado Sucre, Venezuela

    Directory of Open Access Journals (Sweden)

    Johanna Fernández

    2006-12-01

    Full Text Available Se analizó la estructura de la comunidad de moluscos y sus relaciones tróficas en seis localidades del litoral rocoso con diferentes grados de exposición al oleaje (área expuesta y área protegida, en el Estado Sucre, Venezuela. El muestreo se llevó a cabo durante el período de marzo 2003 a febrero 2004. La recolección del material biológico se realizó de forma manual con ayuda de una espátula, dentro de una cuadrícula de 0.25 m², estableciéndose tres zonas: supra, medio e infralitoral. Los organismos fueron preservados en frascos con formalina al 10% para su posterior análisis. En el laboratorio fueron identificados, contados, y pesados en una balanza de 0.001g de precisión. Se determinó la abundancia total de especies, biomasa, constancia específica y por medio de una revisión bibliográfica se le asignó a cada especie su categoría trófica, clasificándolos en: herbívoros, filtradores, carnívoros y herbívoros -filtradores. Se obtuvo un total de 14 581 individuos (6 397.945 g representado por 68 especies correspondientes a las clases Gastropoda (39, Bivalvia (23 y Polyplacophora (6; contenidas en nueve órdenes y 31 familias. Los herbívoros fueron el grupo dominante (49%, seguido por filtradores (37%, carnívoros (13 % y herbívoros-filtradores (1%. Las especies herbívoras y herbívoras-filtradoras dominaron en el área protegida, mientras que en el área expuesta, fueron las carnívoras y filtradoras. Las especies constantes en las seis localidades durante el período de estudio fueron Planaxis nucleus, Mitrella ocellata, M. nycteis, Littorina interrupta, Tegula fasciata, Acmaea leucopleura, Ostrea equestris y Chiton squamosus. La distribución de los moluscos y los diferentes grupos tróficos, pueden estar controlados por adaptaciones morfológicas, así como el nivel de exposición al oleaje y composición del sustrato.Mollusc community structure and trophic relations in the rochy littoral zone in Sucre State

  12. Hydrogeochemical evaluation for Simpevarp model version 1.2. Preliminary site description of the Simpevarp area

    International Nuclear Information System (INIS)

    Laaksoharju, Marcus

    2004-12-01

    Siting studies for SKB's programme of deep geological disposal of nuclear fuel waste currently involves the investigation of two locations, Simpevarp and Forsmark, to determine their geological, hydrogeochemical and hydrogeological characteristics. Present work completed has resulted in Model version 1.2 which represents the second evaluation of the available Simpevarp groundwater analytical data collected up to April, 2004. The deepest fracture groundwater samples with sufficient analytical data reflected depths down to 1.7 km. Model version 1.2 focusses on geochemical and mixing processes affecting the groundwater composition in the uppermost part of the bedrock, down to repository levels, and eventually extending to 1000 m depth. The groundwater flow regimes at Laxemar/Simpevarp are considered local and extend down to depths of around 600-1000 m depending on local topography. The marked differences in the groundwater flow regimes between Laxemar and Simpevarp are reflected in the groundwater chemistry where four major hydrochemical groups of groundwaters (types A-D) have been identified: TYPE A: This type comprises dilute groundwaters ( 3 type present at shallow ( 300 m) levels at Simpevarp, and at even greater depths (approx. 1200 m) at Laxemar. At Simpevarp the groundwaters are mainly Na-Ca-Cl with increasingly enhanced Br and SO 4 with depth. At Laxemar they are mainly Ca-Na-Cl also with increasing enhancements of Br and SO 4 with depth. Main reactions involve ion exchange (Ca). At both sites a glacial component and a deep saline component are present. At Simpevarp the saline component may be potentially non marine and/or non-marine/old Littorina marine in origin; at Laxemar it is more likely to be non-marine in origin. TYPE D: This type comprises reducing highly saline groundwaters (> 20 000 mg/L Cl; to a maximum of ∼70 g/L TDS) and only has been identified at Laxemar at depths exceeding 1200 m. It is mainly Ca-Na-Cl with higher Br but lower SO 4 compared

  13. Candidatus Phytoplasma brasiliense associado ao superbrotamento do hibisco (Hibiscus rosa-sinensis L. no Estado de São Paulo Candidatus Phytoplasma brasiliense associated with hibiscus witches' broom in the State of São Paulo-Brazil

    Directory of Open Access Journals (Sweden)

    Eliane Gonçalves da Silva

    2009-09-01

    of phytoplasma was always detected by molecular technique and electron microscopy in all samples. The RFLP analyses showed that the phytoplasma belongs to group 16SrXV, the same group of the Candidatus Phytoplasma brasiliense. It was experimentally transmitted by C. subinclusa to periwinkle and by grafting to hibiscus in which it reproduced the original symptoms. This indicates that the studied phytoplasma is the causal agent the disease.

  14. SFR site investigation. Bedrock Hydrogeochemistry

    International Nuclear Information System (INIS)

    Nilsson, Ann-Chatrin; Tullborg, Eva-Lena; Smellie, John; Gimeno, Maria J.; Gomez, Javier B.; Auque, Luis F.; Sandstroem, Bjoern; Pedersen, Karsten

    2011-11-01

    -SMOW) similar to that reported from the Forsmark site investigations (Laaksoharju et al. 2008). At the SFR, marine indicators such as Mg/Cl, K/Cl and Br/Cl also show relatively large variations considering the limited salinity range. This information together with palaeoclimatic considerations were used to differentiate the groundwaters into four major types; 1) local Baltic Seawater type, 2) Littorina type water with a glacial component, 3) brackish-glacial water type, and 4) mixed brackish water (transition type). Based on these types, explorative analyses using traditional geochemical approaches have been performed initially to describe groundwater conditions (origin and evolution) followed by further detailed evaluation using different modelling approaches such as mixing modelling, geochemical equilibrium modelling and redox modelling. From measured Eh values, and in accordance with the chemistry of Fe, Mn, S and U, it is concluded that mildly reduced conditions (-140 to -190 mV) generally prevail in the investigated groundwaters and, importantly, also for the youngest Baltic Sea type groundwaters. In terms of redox buffer capacity, the most important fracture minerals available are the Fe(II)-bearing minerals coating the water conductive fractures, which at SFR comprise mainly chlorite, clay minerals and pyrite. Calcite coatings are also frequent, which results in a rapid response to changes in pH by dissolution or precipitation and thereby provides an important buffering capacity against acidification. The division into different groundwater types has facilitated interaction and integration with the geological and hydrogeological models making it possible to construct a hydrogeochemical site descriptive model for the SFR site. The distribution of the different groundwater types shows that the major deformation zones have served as important groundwater flow pathways over long periods of geological time while single discrete fractures in rock volumes between zones

  15. SFR site investigation. Bedrock Hydrogeochemistry

    Energy Technology Data Exchange (ETDEWEB)

    Nilsson, Ann-Chatrin [Geosigma AB, Uppsala (Sweden); Tullborg, Eva-Lena [Terralogica AB, Graabo (Sweden); Smellie, John [Conterra AB, Uppsala (Sweden); Gimeno, Maria J.; Gomez, Javier B.; Auque, Luis F. [Univ. of Zaragoza, Zaragoza (Spain); Sandstroem, Bjoern [WSP Sverige AB, Goeteborg (Sweden); Pedersen, Karsten [Micans AB, Moelnlycke (Sweden)

    2011-11-15

    -SMOW) similar to that reported from the Forsmark site investigations (Laaksoharju et al. 2008). At the SFR, marine indicators such as Mg/Cl, K/Cl and Br/Cl also show relatively large variations considering the limited salinity range. This information together with palaeoclimatic considerations were used to differentiate the groundwaters into four major types; 1) local Baltic Seawater type, 2) Littorina type water with a glacial component, 3) brackish-glacial water type, and 4) mixed brackish water (transition type). Based on these types, explorative analyses using traditional geochemical approaches have been performed initially to describe groundwater conditions (origin and evolution) followed by further detailed evaluation using different modelling approaches such as mixing modelling, geochemical equilibrium modelling and redox modelling. From measured Eh values, and in accordance with the chemistry of Fe, Mn, S and U, it is concluded that mildly reduced conditions (-140 to -190 mV) generally prevail in the investigated groundwaters and, importantly, also for the youngest Baltic Sea type groundwaters. In terms of redox buffer capacity, the most important fracture minerals available are the Fe(II)-bearing minerals coating the water conductive fractures, which at SFR comprise mainly chlorite, clay minerals and pyrite. Calcite coatings are also frequent, which results in a rapid response to changes in pH by dissolution or precipitation and thereby provides an important buffering capacity against acidification. The division into different groundwater types has facilitated interaction and integration with the geological and hydrogeological models making it possible to construct a hydrogeochemical site descriptive model for the SFR site. The distribution of the different groundwater types shows that the major deformation zones have served as important groundwater flow pathways over long periods of geological time while single discrete fractures in rock volumes between zones

  16. Water-rock interaction modelling and uncertainties of mixing modelling. SDM-Site Forsmark

    Energy Technology Data Exchange (ETDEWEB)

    Gimeno, Maria J.; Auque, Luis F.; Gomez, Javier B.; Acero, Patricia (Univ. of Zaragoza, Zaragoza (Spain))

    2008-08-15

    in geochemistry, hydrochemistry, hydrogeochemistry, microbiology, geomicrobiology, analytical chemistry etc. The resulting site descriptive model version, mainly based on 2.2 data and complementary 2.3 data, was carried out during September 2006 to December 2007. Several groups within ChemNet were involved and the evaluation was conducted independently using different approaches ranging from expert knowledge to geochemical and mathematical modelling including transport modelling. During regular ChemNet meetings the results have been presented and discussed. This report presents the modelling work performed by the University of Zaragoza group as part of the work planned for Forsmark during stages 2.2 and 2.3. The chemical characteristics of the groundwaters in the Forsmark and Laxemar areas are the result of a complex mixing process driven by the input of different recharge waters since the last glaciation. The successive penetration at different depths of dilute glacial melt-waters, Littorina Sea waters and dilute meteoric waters has triggered complex density and hydraulically driven flows that have mixed them with long residence time, highly saline waters present in the fractures and in the rock matrix. A general description of the main characteristics and processes controlling the hydrogeochemical evolution with depth in the Forsmark groundwater system is presented in this report: The hydrochemical characteristics and evolution of the Near surface waters (up to 20 m depth) is mainly determined by weathering reactions and especially affected by the presence of limestones. The biogenic CO{sub 2} input (derived from decay of organic matter and root respiration) and the associated weathering of carbonates control the pH and the concentrations of Ca and HCO{sub 3}- in the near-surface environment. Current seasonal variability of CO{sub 2} input produces variable but high calcium and bicarbonate contents in the Forsmark near-surface waters: up to 240 mg/L Ca and 150 to

  17. Water-rock interaction modelling and uncertainties of mixing modelling. SDM-Site Forsmark

    International Nuclear Information System (INIS)

    Gimeno, Maria J.; Auque, Luis F.; Gomez, Javier B.; Acero, Patricia

    2008-08-01

    geochemistry, hydrochemistry, hydrogeochemistry, microbiology, geomicrobiology, analytical chemistry etc. The resulting site descriptive model version, mainly based on 2.2 data and complementary 2.3 data, was carried out during September 2006 to December 2007. Several groups within ChemNet were involved and the evaluation was conducted independently using different approaches ranging from expert knowledge to geochemical and mathematical modelling including transport modelling. During regular ChemNet meetings the results have been presented and discussed. This report presents the modelling work performed by the University of Zaragoza group as part of the work planned for Forsmark during stages 2.2 and 2.3. The chemical characteristics of the groundwaters in the Forsmark and Laxemar areas are the result of a complex mixing process driven by the input of different recharge waters since the last glaciation. The successive penetration at different depths of dilute glacial melt-waters, Littorina Sea waters and dilute meteoric waters has triggered complex density and hydraulically driven flows that have mixed them with long residence time, highly saline waters present in the fractures and in the rock matrix. A general description of the main characteristics and processes controlling the hydrogeochemical evolution with depth in the Forsmark groundwater system is presented in this report: The hydrochemical characteristics and evolution of the Near surface waters (up to 20 m depth) is mainly determined by weathering reactions and especially affected by the presence of limestones. The biogenic CO 2 input (derived from decay of organic matter and root respiration) and the associated weathering of carbonates control the pH and the concentrations of Ca and HCO 3 - in the near-surface environment. Current seasonal variability of CO 2 input produces variable but high calcium and bicarbonate contents in the Forsmark near-surface waters: up to 240 mg/L Ca and 150 to 900 mg/L HCO 3 - . These

  18. Background complementary hydrogeochemical studies. SDM-Site Forsmark

    Energy Technology Data Exchange (ETDEWEB)

    Kalinowski, Birgitta E. (ed.)

    2008-08-15

    ), magnesium (for Littorina), delta18O and c2H (for Glacial) and tritium (for Modified meteoric). Section 3: Application of the Drilling Impact Study (DIS) to Forsmark groundwaters by Mel Gascoyne, Ioana Gurban. In the Drilling Impact Study (DIS) project a tracer is used as an indicator of contamination to attempt to correct the groundwater composition for dilution or contamination by surface waters. By calculating the drilling water volume lost in the fractures during drilling, it is possible to determine how much water should be pumped out from the section before sampling. Section 4: Analytical uncertainties. Ann-Chatrin Nilsson. There is high confidence in the set of major constituents for each sample. Independent methods were used to check the consistency of the major ions and to confirm the concentrations of chloride, sulphate, bromide and iron.The bromide analyses were found to be more uncertain than most other major ions.

  19. Palynological evidence of human activity on the gulf of Gdansk coast during the late holocene

    Directory of Open Access Journals (Sweden)

    Grazyna Miotk-Szpiganowicz

    2010-01-01

    approached their recent position. The development of the Neolithic settlement on the Puck Bay coast as well as those on the Vistula Delta, where the main activity was related to amber processing, seal hunting and fishing, clearly shows a close relationship to the sea-level rise. The occurrence of the third and fourth settlement phases was related to the high sea-level stands in the Subboreal and Subatlantic Periods (post-Littorina, Late Holocene regressions but their character was still strongly related to the coastal environments. The settlement was connected with the dry habitats whose areas increased after the development of the barriers. In the area of the Vistula Delta, settlement conditions depended mainly on the stages of the delta's development. On the shores of Puck Bay, however, the intensity of settlement was closely related to the water level changes.O Golfo de Gdansk está localizado na parte sul do Mar Báltico. As praias do Golfo são dominadas por barreiras de areia formadas em frente à Lagoa do Vistula e à planície deltaica do Vistula pelo lado sudeste-sul, e em frente a Lagoa de Puck a noroeste, tal como acontece na Peninsula de Hel. Paredões costeiros ocorrem, por sua vez, na costa oeste do Golfo. Assentamentos neolíticos ao redor da costa do Golfo de Gdansk estão localizados principalmente no sopé do talude e no Delta do Vistula, sendo estritamente relacionados com a elevação do nível do mar e as decorrentes variações da linha de costa ao longo do Holoceno Tardio. Análises do polen do sedimento obtido nos corers do Delta do Vistula, Lagoa do Vistula e Lagoa Puck permitiram distinguir 4 fases antropogênicas para a área do Golfo de Gdansk. Foi visto que os primeiros indicadores da economia baseada em criação de animais domésticos nas vizinhanças do Golfo apareceram no Período Atlântico. Foram encontrados grãos de polen das plantas relacionadas com esse tipo de atividade humana familia Amaranthaceae (Chenopodiacea, "motherwort