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Sample records for micaceous glauconitic calcareous

  1. MAPPING GLAUCONITE UNITES WITH USING REMOTE SENSING TECHNIQUES IN NORTH EAST OF IRAN

    Directory of Open Access Journals (Sweden)

    R. Ahmadirouhani

    2014-10-01

    Full Text Available Glauconite is a greenish ferric-iron silicate mineral with micaceous structure, characteristically formed in shallow marine environments. Glauconite has been used as a pigmentation agent for oil paint, contaminants remover in environmental studies and a source of potassium in plant fertilizers, and other industries. Koppeh-dagh basin is extended in Iran, Afghanistan and Turkmenistan countries and Glauconite units exist in this basin. In this research for enhancing and mapping glauconitic units in Koppeh-dagh structural zone in north east of Iran, remote sensing techniques such as Spectral Angle Mapper classification (SAM, band ratio and band composition methods on SPOT, ASTER and Landsat data in 3 steps were applied.

  2. Ion exchange of radionuclides on natural and modified micaceous minerals

    International Nuclear Information System (INIS)

    Kojvula, R.; Lekhto, Yu.

    1998-01-01

    Interaction of 134 Cs, 85 Sr and 60 Co with three micaceous minerals: muscovites, biotites and phlogopite is studied. Two types of micaceous minerals: natural ones, wherein potassium is an exchange cation, and samples, converted into sodium form, are studied/ It is found that biotite and phlogopite in the sodium form are specified by high selectivity to cobalt with distribution coefficient above 10 5 ml/g, whereas the muscovite potassium form is characterized by high selectivity to cesium. Neither of the micaceous minerals is characterized by selectivity to strontium. Distribution coefficients strongly depend on pH of the medium

  3. The use of spent glauconite in lightweight aggregate production

    OpenAIRE

    Franus, Wojciech; Franus, Małgorzata; Latosińska, Jolanta; Wójcik, Rafał

    2011-01-01

    The presented work has shown an application of spent glauconite bed after purification of wastewater for production of lightweight expanded clay aggregates. Sewage, from which it was removed Zn ions, came from technological line (zincworks) of Communication Equipment Factory „PZL” Świdnik. Spent glauconite bed was used as an additive in lightweight aggregate production which was obtained using plastic method by sintering, at temperature 1140 ºC and 1200 ºC, of spent glauconite amouts 10, 15, ...

  4. Morphology of channels and channel-sand bodies in the Glauconitic sandstone member (Upper Mannville), Little Bow area, Alberta

    Energy Technology Data Exchange (ETDEWEB)

    Hopkins, J.C.; Hermanson, S.W.; Lawton, D.C.

    1982-12-01

    Large channels in the Glauconitic sandstone member of southern Alberta have proved to be difficult exploration targets because of an irregular distribution of reservoir sands within the channels. In the Little Bow area, two channels are present in the lower part of the Glauconitic member and have cut into the underlying Calcareous member. The channels can be recognized where they truncate regional markers of the Calcareous member -- the Bantry shale and Ostracod limestone, and where channel-fill deposits exhibit uniform geophysical log characters, indicating sandstone- or mudstone-filled reaches. Sediments of the Glauconitic member adjacent to the channels comprise a series of splay sandstones and mudstones that prograded into interdistributary bays of the lower delta plain. The two channels associated with these deposits are interpreted as distributary channels. Sand bodies within the channels formed as lateral bars and are isolated by mudstones which mark the abandoned stream course. Geological exploration for these discontinuous channel sandstones is difficult, and high-resolutio seismic data integrated with sound geologic modelling are critical for successful prospect delineation.

  5. Micaceous Soil Strength And Permeability Improvement Induced By Microbacteria From Vegetable Waste

    Science.gov (United States)

    Omar, R. C.; Roslan, R.; Baharuddin, I. N. Z.; Hanafiah, M. I. M.

    2016-11-01

    Green technology method using vegetable waste are introduced in this paper for improvement of phyllite residual soil from UNITEN, Campus. Residual soil from phyllite are known as micaceous soils and it give problem in managing the stability of the slope especially in wet and extensively dry seasons. Micaceous soil are collected using tube sampler technique and mixed with liquid contain microorganism from fermented vegetable waste name as vege-grout to form remolded sample. The remolded sample are classify as 15.0%, 17.5%, 20.00% and 22.5% based on different incremental percentages of vege-grout. The curing time for the sample are 7, 14, 21, 28, and 35 days before the tests were conducted. Observation of the effect of treatment shows 20.0% of liquid contain Bacillus pasteurii and Bacillus Subtilis with 21 days curing time is the optimum value in strengthening the soil and improve the permeability.

  6. Application of visible and infrared spectroscopy for the evaluation of evolved glauconite

    Science.gov (United States)

    Chattoraj, Shovan L.; Banerjee, Santanu; van der Meer, Freek; Champati Ray, P. K.

    2018-02-01

    The Oligocene Maniyara Fort Formation in western India exhibits two distinct glauconite types with different maturation states, which are characterized by their spectral response in the visible to infrared spectrum of electromagnetic radiation. Spectral signatures of Maniyara Fort glauconites display absorption features at approximately 0.77, 1.08, 1.9, 2.3 μm in the visible-short-wave infrared (SWIR) and 2.8 and 10 μm in the mid-infrared (MIR) region which vary with K2O content of glauconite. The spectra of glauconite varies significantly as a function of its cationic contents and substitution in different sites. The maturity is found to increase in tandem with the metal-metal charge transfer (CT) and the Fe2+ dd absorption band respectively at 1.08 and 0.77 μm. H2O and OH- signatures at the NIR region reflect differences in the sensitivity of glauconites with different molecular H2O content. In the MIR region, a gradual shift of the Sisbnd O stretch at 10 μm towards lower wavelengths indicates the dominance of smectite layers in glauconites. This study demonstrates a strong correlation between the proportion of expandable layers in the glauconite structure with variations in characteristic band position, depth and symmetry in reflectance and emissivity.

  7. The use of spent glauconite in lightweight aggregate production

    Directory of Open Access Journals (Sweden)

    Franus, Wojciech

    2011-08-01

    Full Text Available The presented work has shown an application of spent glauconite bed after purification of wastewater for production of lightweight expanded clay aggregates. Sewage, from which it was removed Zn ions, came from technological line (zincworks of Communication Equipment Factory „PZL” Świdnik. Spent glauconite bed was used as an additive in lightweight aggregate production which was obtained using plastic method by sintering, at temperature 1140 ºC and 1200 ºC, of spent glauconite amouts 10, 15, 20 and 25% wt. with clays from open-cast mine „Budy Mszczonowskie”. The presence of the mineral improves sinter texture, increases porosity and contributes to formation of glassy layer on the surface of the aggregates. Tests of zinc elution from lightweight of aggregate samples has shown very low mobility of zinc ions. Content of zinc in water extracts obtained from lightweight of aggregate is definitely lower than zinc concentration permitted for sewage discharge to water or soil, means that spent material is not offensive for the environment as it can be used as a high quality building product.

    El trabajo presentado ha demostrado una aplicación de agotado depósito de glauconita después de la purificación de aguas residuales para la producción de áridos ligeros de arcilla expandida. Las aguas residuales, de la que fueron eliminados los iones Zn, vinieron de la línea tecnológica del equipo de comunicación de la fábrica “PZL” Świdnik. Agotado depósito de glauconita se utiliza como aditivo en la producción de áridos ligeros que se obtuvo utilizando el método de plástico de la sinterización, a temperatura C. 1140 º y 1200 º C, de spent glauconita amouts10, 15, 20 y 25% en peso. con arcillas de la mina a cielo abierto “Budy Mszczonowskie”. La presencia de este mineral mejora la textura de sinterización, aumenta la porosidad y contribuye a la formación de la capa vítrea en la superficie de los agregados. Pruebas de

  8. Exchange of interlayer cations in micaceous minerals. Final report, February 1, 1967--August 31, 1976

    International Nuclear Information System (INIS)

    Scott, A.D.

    1976-08-01

    Laboratory experiments were carried out to establish a comprehensive understanding of the processes and factors governing the sorption and release of interlayer cations in micaceous minerals. A diverse approach with several lines of work was used to delineate the effects of different procedures, solution compositions and mineral properties. It was soon clear that the major factors controlling the exchange of interlayer cations are the blocking effects of dissolved fixable cations and the limiting effects of small particles. By using sodium tetraphenylboron to reduce the blocking effects and by excluding particles that were smaller than 2 μm, however, the subtle effects of many other factors were brought out. The redox status of structural iron, the hydroxyl groups, the interlayer spacing and the layer charge of the minerals are indicative of the type of factors involved and the fact that they are mainly interactive in nature. One conclusion from this work is that most experimental results for interlayer cation exchange are bound to reflect some combination of the controlling factors. More important, however, was the observation that proper management of interlayer cation exchange can make micaceous minerals a good sink for cesium and source of potassium

  9. Exchange of interlayer cations in micaceous minerals. Progress report, August 1, 1974--July 31, 1975

    International Nuclear Information System (INIS)

    Scott, A.D.

    1975-01-01

    Information pertaining to the sorption and exchange of interlayer cations in micaceous minerals was developed along several lines. Cs sorption experiments with different minerals and particle sizes established the periods required for maximum sorption at different temperatures and downgraded the impact anticipated from a contraction of particle edges by Cs. Added interlayer Cs in even highly charged minerals (degraded muscovite) proved to be very exchangeable in air-dry, clay size particles. Heat treatments greatly retarded the exchange of this sorbed Cs and by doing so have circumvented the commonly observed small particle effects. Structural Fe in micas was shown to be susceptible to oxidation by various Br 2 treatments but these treatments also removed a lot of K that must be accounted for in a determination of changes in interlayer K exchangeability. Changes in the rate of interlayer K exchange were induced in some micaceous minerals by adding H 2 O 2 but not in others. Specific effects of heat treatments on dioctahedral and trioctahedral micas were examined in great detail. Interlayer cation exchange experiments with different concentrations of Na and Al have produced predictable results. (U.S.)

  10. Micaceous occlusions in kaolinite observed by ultramicrotomy and high resolution electron microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Lee, S Y [Univ. of Wisconsin, Madison; Jackson, M L; Brown, J L

    1975-01-01

    The layer structure of kaolinite from Twiggs, Georgia, and fire-clay type kaolinite (Frantex B, from France, particle size separates 2 0.2 ..mu..m was studied by high resolution electron microscopy after embedment in Spurr low-viscosity Epoxy media and thin sectioning normal to the (001) planes by an ultramicrotome. Images of the (001) planes (viewed edge-on) of both kaolinites were spaced at 7 A and generally aligned in parallel, with occasional bending into more widely spaced images of about 10 A interval. Some of the 10 A images converged to 7 A at one or both ends, forming ellipse-shaped islands 80 to 130 A thick and 300 to 500 A long. The island areas and interleaved 10 A layers between 7 A layers may represent a residue of incomplete weathering of mica to kaolinite. The proportions of micaceous occlusions were too small and the layer sequences too irregular to be detected by X-ray diffraction. The lateral continuity of the layers through the 7-10-7 A sequence in a kaolinite particle would partially interrupt or prevent expansion in dimethyl sulfoxide (DMSO) and other kaolinite intercalating media. Discrete mica particles were also observed with parallel images at 10 A, as impurities in both kaolinites. The small K content of the chemical analyses of the kaolinite samples is accounted for as interlayer K, not only in discrete mica particles but also in the micaceous occlusions.

  11. SYNTHESIS AND CORROSION PROTECTION BEHAVIOR OF EPOXYTiO2-MICACEOUS IRON OXIDE NANO - COMPOSITE COATING ON St-37

    Directory of Open Access Journals (Sweden)

    M. R. Khorram

    2016-03-01

    Full Text Available The micro layers micaceous iron oxide and nano-TiO 2 were incorporated into the epoxy resin by mechanical mixing and sonication process. Optical micrographs showed that the number and diameter size of nanoparticle agglomerates were decreased by sonication. The structure and composition of the nanocomposite was determined using transmission electron microscopy which showed the presence of dispersed nano-TiO 2 in the polymer matrix. The anticorrosive properties of the synthesized nano-composites coating were investigated using salt spray, electrochemical impedance spectroscopy and polarization measurement. The EIS results showed that coating resistance increased by addition of micaceous iron oxide micro layers and nano-TiO 2 particles to the epoxy coatings. It was observed that higher corrosion protection of nanocomposite coatings obtained by the addition of 3 %wt micaceous iron oxide and 4%wt nano-TiO 2 into epoxy resin.

  12. Compositional variation of glauconites in Upper Cretaceous-Paleogene sedimentary iron-ore deposits in South-eastern Western Siberia

    Science.gov (United States)

    Rudmin, Maxim; Banerjee, Santanu; Mazurov, Aleksey

    2017-06-01

    Glauconite occurs either as unaltered greenish or as altered brownish variety in Upper Cretaceous-Palaeocene sediments in the southeastern corner of Western Siberia. Studied section within the Bakchar iron-ore deposit includes Ipatovo, Slavgorod, Gan'kino and Lyulinvor formations, which are represented by sandstones, siltstones, claystones and oolitic ironstones of coastal-marine facies. The origin of unaltered glauconite is explained by the ;verdissement theory;. Transgressions during Lower Coniacian, Santonian and Campanian favored the formation of unaltered glauconites in dysoxic to anoxic conditions. Subaerial exposure of glauconite resulted in leaching of potassium, oxidation of iron and formation of iron hydroxides in Upper Coniacian, Maastrichtian and Palaeocene. Glauconite ultimately converts to leptochlorite and hydrogoethite by this alteration. Abundant microscopic gold inclusions, besides sulphides, sulphates, oxides and silicates characterize this glauconite. Mineral inclusions include precious, rare metals and non-ferrous metals. The concentration of gold in glauconite may be as high as 42.9 ppb. Abundant inclusions of various compositions in glauconites indicate enrichment of marine sediments in precious and non-precious metals. While major element composition of glauconites is affected by subaerial exposure, the broadly similar micro-inclusions in both altered and unaltered varieties are possibly related to the comparatively immobile nature of REE and trace elements.

  13. Liquefaction resistance of calcareous sands

    International Nuclear Information System (INIS)

    Sandoval Vallejo, Eimar

    2012-01-01

    Calcareous sands are unique in terms of their origin, mineralogy, shape, fragility and intra particle porosity. This article presents results from an experimental program carried out to study the liquefaction resistance of a calcareous sand retrieved from Cabo Rojo at Puerto Rico. The experimental program included mineralogical characterization, index properties, and undrained cyclic triaxial tests on isotropically consolidated reconstituted samples. Due to the large variation in the calcareous sand properties, results are compared with previous researches carried out on other calcareous sands around the world. Results showed a wide range in the liquefaction resistance of the studied calcareous sands. Cabo Rojo sand experienced greater liquefaction resistance than most of the calcareous sands used for comparison. Important differences in the excess pore pressure generation characteristics were also found.

  14. Moessbauer study of dissimilatory reduction of iron contained in glauconite by alkaliphilic bacteria

    Energy Technology Data Exchange (ETDEWEB)

    Chistyakova, Nataliya I., E-mail: nchistyakova@yandex.ru; Rusakov, Vyacheslav S.; Shapkin, Alexey A. [M.V. Lomonosov Moscow State University, Faculty of Physics (Russian Federation); Zhilina, Tatyana N.; Zavarzina, Darya G. [Russian Academy of Sciences, Winogradsky Institute of Microbiology (Russian Federation)

    2012-03-15

    {sup 57}Fe Moessbauer investigations of glauconite and new solid phases formed during the process of the bacterial growth in alkaline environment were carried out at room temperature, 78 K and 4.8 K. The magnetically ordered phase formed during bioleaching of glauconite by G. ferrihydriticus in pure culture or in combination with Cl. alkalicellulosi represented as a mixture of off-stoichiometric magnetite and maghemite. In case of combined binary bacterium culture growth the relative content of magnetically ordered phase was more than for the G. ferrihydriticus growth.

  15. Mössbauer study of dissimilatory reduction of iron contained in glauconite by alkaliphilic bacteria

    International Nuclear Information System (INIS)

    Chistyakova, Nataliya I.; Rusakov, Vyacheslav S.; Shapkin, Alexey A.; Zhilina, Tatyana N.; Zavarzina, Darya G.

    2012-01-01

    57 Fe Mössbauer investigations of glauconite and new solid phases formed during the process of the bacterial growth in alkaline environment were carried out at room temperature, 78 K and 4.8 K. The magnetically ordered phase formed during bioleaching of glauconite by G. ferrihydriticus in pure culture or in combination with Cl. alkalicellulosi represented as a mixture of off-stoichiometric magnetite and maghemite. In case of combined binary bacterium culture growth the relative content of magnetically ordered phase was more than for the G. ferrihydriticus growth.

  16. Vp-Vs relationship and amplitude variation with offset modelling of glauconitic greensand

    DEFF Research Database (Denmark)

    Hossain, Zakir; Mukerji, Tapan; Fabricius, Ida Lykke

    2012-01-01

    The relationship between Vp and Vs may be used to predict Vs where only Vp is known. Vp/Vs is also used to identify pore fluids from seismic data and amplitude variation with offset analysis. Theoretical, physical, as well as statistical empirical Vp-Vs relationships have been proposed...... modelling works well for greensand shear-wave velocity prediction. We model the seismic response of glauconitic greensand by using laboratory data from the Nini field. Our studies here reveal that brine-saturated glauconitic greensand can have a similar seismic response to that from oil-saturated quartzitic...

  17. Glauconitic deposits at Julegård on the south coast of Bornholm, Denmark dated to the Cambrian

    DEFF Research Database (Denmark)

    Clemmensen, Lars B.; Bromley, Richard Granville; Holm, Paul Martin

    2011-01-01

    Bioturbated, glauconitic siltstones and sandstones are overlain by presumed Upper Triassic deposits at coastal exposures at Julegård on the south coast of Bornholm. These glauconitic deposits have not previously been dated. A 40Ar-39Ar dating of the glaucony gives an age of 493 ± 2 Ma suggesting ...... of Rusophycus Hall, 1852, probably trilobite trace fossils, are also represented....

  18. Calcareous Fens - Source Feature Points

    Data.gov (United States)

    Minnesota Department of Natural Resources — Pursuant to the provisions of Minnesota Statutes, section 103G.223, this database contains points that represent calcareous fens as defined in Minnesota Rules, part...

  19. Earthworm introduction on calcareous minesoils

    International Nuclear Information System (INIS)

    Vimmerstedt, J.P.; Kost, D.A.

    1994-01-01

    Burrowing activity of the nightcrawler, Lumbricus terrestis (L.t.), incorporates organic matter into mineral soil while creating long-lasting macropores. Thus L.t. has potential as a biological means of improving physical and chemical properties of surface mined areas. Efforts to establish L.t. population on forested acidic or calcareous minesoils have been successful, but thus far have not been able to establish L.t. in grassland ecosystems on calcareous minesoils. In May, 1989, the authors put 11 clitellate L.t. under sphagnum moss on calcareous gray cast overburden on standard graded topsoil, or on ripped and disked topsoil. All soils had cover of agronomic grasses and legumes. They found no L.t. at the 24 points of inoculation during sampling in fall of 1990 with formalin extractant, although smaller species, Lumbricus rubellus and Dendrobaena spp., were found. At another location, in May, 1990, they put 25 clitellate L.t. at 16 points in grasslands growing on gray cast overburden. Using formalin extraction, they found no L.t. in May 1992 at these locations. Working in this same area in November, 1992, they released 10 clitellate L.t. at 16 points under 10 cm of moist Alnus glutinosa leaf litter. Careful examination of the surface inoculation points in spring and fall of 1993 did not show obvious signs of earthworm activity. Their next step will be to use Earthworm Inoculation Units (earthworm-minesoil microcosms containing L.t. adults, immatures, and cocoons) as the source of the new populations

  20. Differentiation of Palaeogene sand by glauconitic and geochemical fingerprinting, Siri Canyon, Danish North Sea

    Energy Technology Data Exchange (ETDEWEB)

    Olivarius, M.; Knudsen, Christian; Svendsen, Johan B.

    2011-07-01

    The submarine Siri Canyon is NE-SW-oriented and located in the Danish North Sea. It contains a number of oil reservoirs with glauconite-rich sand. The reservoirs of interest in the Nini oil field are the Late Paleocene Tyr Member of the Lista Formation and the Kolga Member of the Sele Formation, presumably of Early Eocene age. These members have previously been known as the Ty and Hermod members. The sand shows signs of injection, both in cores and in seismic data. The aim of this work is to chemically characterise and fingerprint the sand in order to reveal the origin of the sand found in three horizontal wells, which could have been injected from one or both of the Tyr and Kolga members. Core samples were collected from two vertical wells of known stratigraphy to make a basis of comparison, whereas samples of the cuttings were collected from the three horizontal wells with ages primarily corresponding to the Kolga Member. The purpose was moreover to evaluate whether cuttings samples can be used for fingerprinting as an alternative to core samples. The interest in discriminating between the ages of the injected sand is the fact that the reservoir properties (porosity and permeability) are largely controlled by the original composition of the sand. Consequently, results from this study could affect the property modelling of the field. (LN)

  1. Properties, durability and use of glauconitic Godula sandstones: a relatively less known building stone of the Czech Republic and Poland

    Czech Academy of Sciences Publication Activity Database

    Vavro, Martin; Vavro, Leona; Martinec, Petr; Souček, Kamil

    2016-01-01

    Roč. 75, č. 22 (2016), s. 1-17, č. článku 1437. ISSN 1866-6280 R&D Projects: GA MŠk(CZ) LO1406; GA MŠk ED2.1.00/03.0082 Institutional support: RVO:68145535 Keywords : glauconitic sandstones * flysch sediments * properties * porosity * stone durability * Teschen Silesia Subject RIV: DB - Geology ; Mineralogy Impact factor: 1.569, year: 2016 http://link.springer.com/article/10.1007/s12665-016-6248-3

  2. Transport of Calcareous Fragments by Reef Fishes.

    Science.gov (United States)

    Bardach, J E

    1961-01-13

    The weight of sand, coral scrapings, algal fragments, and other calcareous materials which pass through the intestines of reef fishes was calculated on a hectare-per-year basis. It was found that browsing omnivorous reef fishes which rely, in part, on a plant diet ingested and redeposited at least 2300 kg of such material on a 1-hectare study reef near Bermuda. Reasons are presented why this estimate, certainly in order of magnitude, should be applicable to coral reefs in general.

  3. Patellar calcar: MRI appearance of a previously undescribed anatomical entity

    International Nuclear Information System (INIS)

    Collins, Mark S.; Tiegs-Heiden, Christin A.; Stuart, Michael J.

    2014-01-01

    The femoral calcar is a constant anatomical structure within the proximal femur representing a condensation of bone trabeculae. It is our impression that a similar structure is present within the patella. The purpose of this retrospective study was to define the prevalence, appearance, location, and configuration of the patellar calcar on MRI examinations. One hundred consecutive unenhanced knee MRIs were retrospectively reviewed by two readers who were blinded to the clinical indication. The patellar calcar was defined as a dark signaling, linear or curvilinear structure subjacent to the patellar articular surface. If present, the patellar calcar was assigned to a ''well seen,'' ''moderately well seen,'' or ''faintly seen'' category. Location of the calcar within the patella, orientation, configuration, and thickness were recorded. Confounding variables, such as marrow edema, patellar chondromalacia, bipartite patella, or postoperative changes were also recorded. The patellar calcar was visualized in 81 out of 100 (81 %) MRIs. When detected, the calcar was well seen in 20 out of 81 (25 %), moderately well seen in 35 out of 81 (43 %), and faintly seen in 26 out of 81 (32 %). The anteroposterior width of the calcar measured at its thickest segment was: 1 mm in 10 out of 81 (12 %). The patellar calcar was seen in the majority of knee MRIs and had a consistent imaging appearance. The calcar may be obscured by degenerative arthrosis of the patella and rarely may mimic patellar stress fracture or osteochondritis dissecans. Radiologists and clinicians should be familiar with this normal anatomical structure. (orig.)

  4. AE Test of Calcareous Sands with Particle Rushing

    Directory of Open Access Journals (Sweden)

    Tan Fengyi

    2017-08-01

    Full Text Available The particle of calcareous sands was forced to crush, then the energy from the crushing was released by the form of sound waves. Therefore the AE technique was used to detect the calcareous sands AE signal when it crushed. by to study the AE characteristics, the mechanics of calcareous sands was studied. Study showed that: (1 there was the AE activities on the low confining pressure condition at the beginnig of test, (2 there was more and more AE activities with the continuing of test until to the end, (3 the calcareous sands’ AE activities was on the whole testing, (4 the calcareous sands’ particle crushing and mutual friction played different roles for its AE activities. Then the AE model based on the calcarous sands’ particle crushing was discussed.

  5. Evaluation of the corrosion resistance of an epoxy-polyamide coating containing different ratios of micaceous iron oxide/Al pigments

    International Nuclear Information System (INIS)

    Nikravesh, B.; Ramezanzadeh, B.; Sarabi, A.A.; Kasiriha, S.M.

    2011-01-01

    Research highlights: → The corrosion resistance of the coating was improved using MIO and Al pigments. → The greatest coating corrosion resistance was observed at MIO/Al ratio of 10/90. → The cathodic disbonded area of the coating was decreased using MIO and Al particles. → The lowest disbonded area was observed at MIO/Al ratio of 10/90. → Al particles had high capability of reacting with the OH - ions. - Abstract: The corrosion resistance of an epoxy coating reinforced with different ratios of MIO/Al pigments was studied. The coatings properties were investigated by an electrochemical impedance spectroscopy (EIS), salt spray test, cathodic disbonding and a scanning electron microscope (SEM). The corrosion resistance of the epoxy coating was improved using MIO (micaceous iron oxide) and Al pigments. The corrosion resistance of the purely Al pigmented coating was considerably greater than the purely MIO pigmented coating. The cathodic disbonded area of coating was decreased using MIO and Al pigments. The decrease in disbonded area was more pronounced in the presence of Al particles.

  6. Patellar calcar: MRI appearance of a previously undescribed anatomical entity

    Energy Technology Data Exchange (ETDEWEB)

    Collins, Mark S.; Tiegs-Heiden, Christin A. [Department of Radiology, Mayo Clinic, Rochester, Minnesota (United States); Stuart, Michael J. [Department of Orthopedic Surgery, Mayo Clinic, Rochester, Minnesota (United States)

    2014-02-15

    The femoral calcar is a constant anatomical structure within the proximal femur representing a condensation of bone trabeculae. It is our impression that a similar structure is present within the patella. The purpose of this retrospective study was to define the prevalence, appearance, location, and configuration of the patellar calcar on MRI examinations. One hundred consecutive unenhanced knee MRIs were retrospectively reviewed by two readers who were blinded to the clinical indication. The patellar calcar was defined as a dark signaling, linear or curvilinear structure subjacent to the patellar articular surface. If present, the patellar calcar was assigned to a ''well seen,'' ''moderately well seen,'' or ''faintly seen'' category. Location of the calcar within the patella, orientation, configuration, and thickness were recorded. Confounding variables, such as marrow edema, patellar chondromalacia, bipartite patella, or postoperative changes were also recorded. The patellar calcar was visualized in 81 out of 100 (81 %) MRIs. When detected, the calcar was well seen in 20 out of 81 (25 %), moderately well seen in 35 out of 81 (43 %), and faintly seen in 26 out of 81 (32 %). The anteroposterior width of the calcar measured at its thickest segment was: < 1 mm in 43 out of 81 (53 %), 1 mm in 28 out of 81 (35 %), and >1 mm in 10 out of 81 (12 %). The patellar calcar was seen in the majority of knee MRIs and had a consistent imaging appearance. The calcar may be obscured by degenerative arthrosis of the patella and rarely may mimic patellar stress fracture or osteochondritis dissecans. Radiologists and clinicians should be familiar with this normal anatomical structure. (orig.)

  7. Physical behaviour of Cretaceous calcareous nannofossil ooze

    DEFF Research Database (Denmark)

    Buls, Toms; Anderskouv, Kresten; Friend, Patrick L.

    2017-01-01

    Geomorphic features such as drifts, sediment waves and channels have been documented in the Upper Cretaceous of north-west Europe. These features are interpreted to result from bottom currents and have been used to refine chalk depositional models and quantify palaeocirculation patterns. Chalk...... was first deposited as calcareous nannofossil ooze and geomorphic features are the result of sediment reworking after deposition. There is limited knowledge on the processes that govern nannofossil ooze mobility, thus forcing uncertainty onto numerical models based on sedimentological observations...... of deposition thresholds (τcd) from ca 0·04 to 0·13 Pa reflects the influence of variable suspended sediment concentration and τ0 on settling particle size due to the identified potential for chalk ooze aggregation and flocculation. Additionally, deposition thresholds seem to be affected by the size of eroded...

  8. Formation and dissolution of zeolite during burial diagenesis - Examples from glauconitic sandstones in the Palaeogene Siri Canyon, Danish North Sea

    DEFF Research Database (Denmark)

    Kazerouni, Afsoon Moatari; Friis, Henrik; Svendsen, Johan B

    or diagenetic alteration of volcanic glass. Authigenic zeolites are uncommon constituents in most sandstones. However, authigenic zeolites are common in some of the glauconitic sandstones from the Siri Canyon, where it is generally associated with thick coatings of opal/microquartz on the detrital framework...... reflecting dissolution of an early phase with different chemical composition. In many samples, zeolites have been totally dissolved, leaving impression marks in the opal/microquartz coating. The textural relation demonstrates that zeolite was dissolved after microquartz precipitation. In most case...

  9. Endogenous and bioaugmented sulphate reduction in calcareous gypsiferous soils

    NARCIS (Netherlands)

    Alfaya, F.; Cuenca-Sanchez, M.; Garcia-Orenes, F.; Lens, P.N.L.

    2009-01-01

    Gypsiferous soils have a high agricultural value, but their utilization is limited by the presence of gypsum that can induce hardpan and vertical crusting. This paper reports on sulphate reduction in this soil type as a basis of a bioremediation technology to remove the gypsum content of calcareous

  10. Highly calcareous lacustrine soils in the Great Konya Basin, Turkey

    NARCIS (Netherlands)

    Meester, de T.

    1971-01-01

    The Great Konya Basin is in the south of the Central Anatolian Plateau in Turkey. It is a depression without outlet to the sea. The central part of the Basin is the floor of a former Pleistocene lake, the Ancient Konya Lake. This area, called the Lacustrine
    Plain, has highly calcareous

  11. The Use of AIS Data for Identifying and Mapping Calcareous Soils in Western Nebraska

    Science.gov (United States)

    Samson, S. A.

    1985-01-01

    The identification of calcareous soils, through unique spectral responses of the vegetation to the chemical nature of calcareous soils, can improve the accuracy of delineating the boundaries of soil mapping units over conventional field techniques. The objective of this experiment is to evaluate the use of the Airborne Imaging Spectrometer (AIS) in the identification and delineation of calcareous soils in the western Sandhills of Nebraska. Based upon statistical differences found in separating the spectral curves below 1.3 microns, calcareous and non-calcareous soils may be identified by differences in species of vegetation. Additional work is needed to identify biogeochemical differences between the two soils.

  12. Assessment of the Hindlimb Membrane Musculature of Bats: Implications for Active Control of the Calcar.

    Science.gov (United States)

    Stanchak, Kathryn E; Santana, Sharlene E

    2018-03-01

    The striking postcranial anatomy of bats reflects their specialized ecology; they are the only mammals capable of powered flight. Bat postcranial adaptations include a series of membranes that connect highly-modified, or even novel, skeletal elements. While most studies of bat postcranial anatomy have focused on their wings, bat hindlimbs also contain many derived and functionally important, yet less studied, features. In this study, we investigate variation in the membrane and limb musculature associated with the calcar, a neomorphic skeletal structure found in the hindlimbs of most bats. We use diffusible iodine-based contrast-enhanced computed tomography and standard histological techniques to examine the calcars and hindlimb membranes of three bat species that vary ecologically (Myotis californicus, a slow-flying insectivore; Molossus molossus, a fast-flying insectivore; and Artibeus jamaicensis, a slow-flying frugivore). We also assess the level of mineralization of the calcar at muscle attachment sites to better understand how muscle contraction may enable calcar function. We found that the arrangement of the calcar musculature varies among the three bat species, as does the pattern of mineral content within the calcar. M. molossus and M. californicus exhibit more complex calcar and calcar musculature morphologies than A. jamaicensis, and the degree of calcar mineralization decreases toward the tip of the calcar in all species. These results are consistent with the idea that the calcar may have a functional role in flight maneuverability. Anat Rec, 301:441-448, 2018. © 2018 Wiley Periodicals, Inc. © 2018 Wiley Periodicals, Inc.

  13. TL studies of calcareous rocks of Danta area, North Gujarat

    International Nuclear Information System (INIS)

    Limaye, M.A.; Desai, S.J.; Murthy, K.V.R.; Joshi, T.R.

    1992-01-01

    The lithounits exposed around Danta in Banaskantha district of North Gujarat belong to Ajabgarh Group, the upper division of the Delhi super group. These rocks are intruded by syn to late kinematic basic rocks and by Erinpura granites of post Delhi age. The Ajabgarh group consists of pelitic and calcareous components. Mineralogically the pelitic rocks comprise cordierite, almandine garnet, k-feldspar, sillimanite, quartz and mica in variable proportions. The calcareous rocks are seen to contain dominantly calcite, scapolite, forsterite, sphene, k-feldspar. These mineral assemblages correspond to upper Amphibolite to lower Granulite facies of regional metamorphism. The chemistry of the calcareous rocks show predominance of CaO over MgO. The glow curves obtained from virgin samples (NTL) as well as artificial beta irradiated indicate glow peaks at 140 o C, 290 o C, 310 o C and 390 o C. The TL glow peak temperatures are in general agreement with those reported by Borsi and Rinaldi and Medlin. The pronounced peak at 390 o C and 290 o C are suggestive of their high irradiation sensitivity and also probably reflect variation in the Mn content of the rocks. (author). 9 refs., 16 tabs., 2 figs

  14. Distribution characteristics of Shihongtan uranium deposits calcareous sandstone and discussion on their genesis

    International Nuclear Information System (INIS)

    Zhu Huanqiao; Jia Heng; Xu Gaozhong; Li Zhanyou

    2007-12-01

    It is considered that the calcareous sandstone appear at layer along of a bunch of pear lens on and off, localled near up and down surface of sandbody or washed surface, has sandstone of more macro-grain and more gradation through statistics and analysis of calcareous sandstone in goal layer in Shihongtan uranium deposits. The calcareous sandstone accumulation thickness chorogram demonstrated that the calcareous sandstone centralized distribution in the ore body growth area, thus it can be seen, in the oxidation reduction intermediate belt the calcareous sandstone forms with the uranium mine has the certain origin relation. Choropleth map of summed thickness of calcareous sandstone deserves that it mainly appear in area of uranium body and related cause of formation of ore body of interlayer deacidizing--oxidation belt. (authors)

  15. Discussion on distribution characteristics of calcareous sandstone in Shihongtan uranium deposit and its genesis

    International Nuclear Information System (INIS)

    Zhu Huanqiao; Qiao Haiming; Jia Heng; Xu Gaozhong

    2007-01-01

    Based on the observation and statistics on the calcareous sandstone in the ore host layer in Shihongtan uranium deposit, this paper finds that the calcareous sandstone occurs on and off near the top or wash surface of the sandbody as beads-strings lens along the layer and concentrates in the area where the ore bodies are rich. In lithology, the calcareous sandstone is of coarse grain and fairly well sorted. According to the analysis on the lithogeochemical features and the carbon and oxygen isotopes of calcareous sandstones, it is realized that there some genetic relation between the formation of calcareous sandstone and uranium mineralization in the oxidation-deoxidation transitional belt, that is the precipitation and enrichment of uranium is accompanied by the deposition of carbonate and formation of calcareous sandstone. (authors)

  16. Effect of FYM on the recovery of applied zinc in DTPA extract under upland and submerged conditions in calcareous and non-calcareous soils

    International Nuclear Information System (INIS)

    Deb, D.L.; Leelabhai, K.S.

    1988-01-01

    Studies undertaken to determine the effect of varying levels of FYM application on the recovery of applied zinc in DTPA extract under upland and sub merged conditions in calcareous and non-calcareous soils using 65 Zn under controlled conditions showed that the recovery of fertilizer Zn was reduced significantly with high level of applied Zn and 5 cm standing water over the soil. Application of FYM also tended to reduce the percent recovery of applied Zn. The recovery of applied Zn was found to increase after 60 days (period of contact) in all the tretments. The calcareous soils showed significantly lower recovery of fertilizer Zn than non-calcareous soils. The interactions of 5 cm standing water with all the other factors studied on the recovery of applied Zn were highly significant and negative. (author). 8 refs., 3 tabs

  17. Long-term after-effects of fertilisation on restoration of calcareous grasslands

    NARCIS (Netherlands)

    Smits, N.A.C.; Bobbink, R.; Willems, J.H.

    2008-01-01

    Question: What are the long-term implications of former fertilisation for the ecological restoration of calcareous grasslands? Location: Gerendal, Limburg, The Netherlands. Methods: In 1970, ten permanent plots were established in just abandoned agricultural calcareous grassland under a regime of

  18. Potential of endozoochorous seed dispersal by sheep in calcareous grasslands: correlations with seed traits.

    NARCIS (Netherlands)

    Kuiters, A.T.; Huiskes, H.P.J.

    2010-01-01

    Questions: What is the potential of sheep to serve as seed dispersers via ingestion and defecation in calcareous grasslands? Is the presence of viable seeds from dung correlated with specific seed traits? Location: Calcareous grasslands, South Limburg, the Netherlands/Belgium. Methods: Dung samples

  19. Calcareous nannofossil events in the pre-evaporitic Messinian

    Science.gov (United States)

    Negri, Alessandra; Lozar, Francesca

    2017-04-01

    During the Messinian (7.2 to 5.3 Ma) the Mediterranean area experienced fast and deep climatic and eustatic structural changes. The stratigraphic framework for this interval is relatively well constrained and the beginning of the Messinian salinity crisis dated at 5.97 Ma determine a duration of at least 1.2 Ma for the pre-evaporitic Messinian that is object of this study. Several sites (Faneromeni, Pissouri, Polemi Fanantello borehole, Lemme, Pollenzo, Govone, Moncalvo; Wade and Bown, 2006; Kouwenhoven et al 2006, Morigi et al 2007, Lozar et al 2010, Dela Pierre et al 2011) show similar calcareous nannofossil record behavior, with several Sphenolithus spp. peaks recognised at different quotes in each of the sections. Aim of the present work is to compare the calcareous nannofossil data achieved in the above mentioned sections: interestingly, the occurrence of strongly oligotypic assemblages related to high salinity and unstable environments, appear to correlate precisely among the investigated sites and occur immediately before the onset of the Messinian salinity crisis, then offering the possibility to use them as bioevents for regional correlation. References Dela Pierre, F., Bernardi, E., Cavagna, S., Clari, P., Gennari, R., Irace, A., Lozar, F., Lugli, S., Manzi, V., Natalicchio, M., Roveri, M., Violanti, D., 2011. The record of the Messinian salinity crisis in the Tertiary Piedmont Basin (NW Italy): The Alba section revisited. Palaeogeography, Palaeoclimatology, Palaeoecology 310, 238-255. Kouwenhoven, T.J., Morigi, C., Negri, A., Giunta, S., Krijgsman, W., Rouchy, J.M., 2006 Paleoenvironmental evolution of the eastern Mediterranean during the Messinian: Constraints from integrated microfossil data of the Pissouri Basin (Cyprus). Marine Micropaleontology 60, 17-44. Lozar, F., Violanti, D., Dela Pierre, F., Bernardi, E., Cavagna, S., Clari, P., Irace, A., Martinetto, E., Trenkwalder, S., 2010. Calcareous nannofossils and foraminifers herald the Messinian

  20. The effect of elevated CO2 and N on decomposition of wheat straw and alfalfa residues in calcareous and non calcareous soils

    Directory of Open Access Journals (Sweden)

    S. Razavi Darbar

    2016-04-01

    Full Text Available Incorporation of plant residue in soils is considered as an important agricultural practice for maintaining soil fertility in sustainable agricultural system. CO2 levels, nitrogen fertilization and plant residues are factors which highly affect decomposition of added organic matter to soil. In this research controlled chambers were used to investigate the effects of elevated atmospheric CO2 concentrations (350 vs. 760 CO2 ppm under two N fertilization levels (0 vs. 500 kg N ha-1 and two replicates on decomposition of wheat and alfalfa residues in two calcareous (32.66 % CaCO3 and non calcareous soils (3.4 % CaCO3 at 6 times (0, 10, 20, 40, 60 and 90 under laboratory condition. Soil moistures were adjusted at 70% of field capacity. The results showed that elevated CO2 significantly increased decomposition of residues in both calcareous and non calcareous soils. In the samples that received N fertilizer, decomposition of wheat straw and alfalfa residues increased in both soils. From the obtained results, we concluded that in all treatments the amount of decomposition of wheat straw and alfalfa residues in calcareous soil were higher than non calcareous soils.

  1. Experimental assessment of the liquefaction resistance of calcareous biogenous sands

    Directory of Open Access Journals (Sweden)

    Sandoval Eimar

    2012-10-01

    Full Text Available

    ABSTRACT

    Liquefaction is a phenomenon in which soils, typically sands, suddenly loose a substantial amount of their shear strength and stiffness, this often triggered by large-magnitude earthquakes. Most liquefaction research has focused on silicate-based sands and not on other sand types, such as calcareous biogenous sands Calcareous sands are usually composed of skeletal or non-skeletal remains of marine organisms, with unique characteristics in terms of their mineralogy surface roughness, particle shape, crushability, and intraparticle porosity. The unique characteristics of calcareous sands suggest that their geotechnical engineering behaviour can be substantially different compared to that of terrigenous sands, including their behaviour under seismic loading, which have not been very well studied

    This paper presents the results of an experimental programme aimed at studying the cyclic liquefaction resistance of uncemented calcareous biogenous sands retrieved from south-western Puerto Rico Evaluation of liquefaction potential involved a comprehensive set of isotropically consolidated undrained cyclic triaxial tests on reconstituted samples of this calcareous sand. The programme also included tests on Ottawa terrigenous silica sand samples prepared and tested in similar conditions for comparison purposes.

    In general, the experimental results showed that Cabo Rojo calcareous sands had higher liquefaction resistance compared to Ottawa silica sands tested under similar conditions. Important differences between calcareous and silica sands regarding pore pressure generation characteristics and axial strain accumulation were also observed


  2. Were Oceanic Plateaus Instrumental for Calcareous Nannoplankton Evolution?

    Science.gov (United States)

    Erba, E.; Casellato, C.; Bottini, C.

    2011-12-01

    The history of calcareous nannoplankton shows a general increase in species richness through the Mesozoic. Fertility and chemistry of the oceans, climate and pCO2 seem instrumental for nannoplankton abundance, diversification and adaptation, but high-resolution chronology of paleobiological and geological events is crucial for the understanding of evolutionary processes relative to ecosystem perturbations. Natural variations in atmospheric CO2 are essentially triggered by igneous activity and the role of ocean crust production in the evolution of seawater composition, nutrient cycling, climate change and, consequently, in calcareous nannoplankton biodiversity, might be more relevant than generally thought. Indeed, two major steps in nannofloral Mesozoic evolution correlate with construction of gigantic oceanic plateaus, namely the Shatsky Rise (SR) (Tithonian/Berriasian boundary interval) and the Ontong Java Plateau (OJP) (Barremian/Aptian boundary interval). During the latest Jurassic calcareous nannoplankton experienced a rapid diversification and rise in abundance of several taxa including heavily calcified nannoliths with consequent major increase in biogenic calcite production. The Tithonian origination of coccoliths and nannoliths suggests ideal paleoecological conditions for calcareous nannoplankton, presumably thriving in stable, relatively oligotrophic and cool oceans under low pCO2. Recent data indicate that this speciation and calcification episode was interrupted during magnetochron CM19r, prior to massive diversification of nannoconids. In the late Barremian-early Aptian interval, the nannoconid decline and crisis are paralleled by a major nannoplankton (mainly coccolith) speciation episode. Such calcification failure and coccolith diversification might reflect disruption of the thermocline, increased fertility and warming under excess CO2 levels. These evolutionary steps show rapid speciation, but differ because nannoliths became dominant in the late

  3. Production of Calcareous Nannofossil Ooze for Sedimentological Experiments

    DEFF Research Database (Denmark)

    Buls, Toms; Anderskouv, Kresten; Fabricius, Ida Lykke

    2015-01-01

    by an abundance of sedimentary structures, such as drifts, moats, sediment waves, and channels documented in the Upper Cretaceous Chalk Group of NW Europe. Despite chalk being a major hydrocarbon reservoir rock of the North Sea, surprisingly little is known about the physical behavior of the pelagic carbonate......The notion of fine-grained pelagic carbonates as uniform, monotonous sequences of sediments settled in a quiescent environment has been challenged over the past few decades. Fine-grained pelagic carbonates can undergo substantial reworking after their first deposition, as illustrated...... sediment from which the chalk formed-calcareous nannofossil ooze. This poses a serious challenge to the understanding of the depositional system and the properties of facies distribution. Experimental tests, such as those performed in laboratory flumes, are necessary to provide empirical data...

  4. Medial Calcar Support and Radiographic Outcomes of Plate Fixation for Proximal Humeral Fractures

    Directory of Open Access Journals (Sweden)

    Shih-Jie Lin

    2015-01-01

    Full Text Available Plate fixation remains one of the most popular surgical procedures for treating proximal humeral fractures (PHFx; however, substantial rates of complications have been reported in the literature. The objectives of the study were to examine how medial calcar support (MCS affects the radiographic outcomes and to determine the prognostic factors predicting treatment failure. We performed a retrospective cohort study of 89 adult patients who had PHFx and were treated with plate fixation at our institution in 2007–2011. The enrolled patients were separated into two groups according to disruption of medial calcar. Our results revealed an increased rate of poor radiographic outcomes in patients with disrupted medial calcar. Osteonecrosis of the humeral head and redisplacement were the two radiographic outcomes which had a positive causality with disruption of medial calcar (P=0.008 and 0.050, resp.. Deficient medial calcar, inadequate reduction, diabetes mellitus, chronic kidney disease, and chronic liver disease were all significant predictors for the development of osteonecrosis in patients after PHFx surgery. Inadequate reduction was also a predictor for redisplacement. We confirmed that the restoration of medial calcar as well as comorbid conditions plays key roles in treatment of patients having PHFx with disrupted medial calcar.

  5. Late Palaeozoic calcareous algae in the Pisuerga basin (N-Palencia, Spain)

    NARCIS (Netherlands)

    Rácz, L.

    1965-01-01

    The calcareous algae were important rock-builders in the deposition of the many limestone members of the Pisuerga Basin. Systematic descriptions are given of 12 species. The following species are new: Clavaporella reinae, Clavaphysoporella endoi, Epimastopora camasobresensis, Psuedoepimastopora?

  6. Consolidation and strength properties of calcareous sediments from Kaneohe and Kailua Bays, Hawaii

    Digital Repository Service at National Institute of Oceanography (India)

    Brandes, H.G.; Khadge, N.H.; Nakayama, D.D.

    behavior of marine calcareous sediments of biogenic origin. Consolidation and drained triaxial tests indicate that mixed sediments have higher compressibilities and lower strengths compared to high-carbonate sediments. Differences in gradation among high...

  7. Biosuper as a phosphate fertilizer in a calcareous soil with low ...

    African Journals Online (AJOL)

    SERVER

    2007-06-04

    Jun 4, 2007 ... Key words: Zea mays, phosphorus uptake, phosphorus fertilization, corn, Thiobacillus, rock phosphate. ... improve plant nutrients availability in calcareous soils and .... lus elicits the reaction of sulphur with water and oxygen, ...

  8. Specialist plant species harbour higher reproductive performances in recently restored calcareous grasslands than in reference habitats

    OpenAIRE

    Harzé, Mélanie; Mahy, Grégory; Bizoux, Jean-Philippe; Piqueray, Julien; Monty, Arnaud

    2015-01-01

    Background and aims_Calcareous grasslands are local biodiversity hotspots in temperate regions that suffered intensive fragmentation. Ecological restoration projects took place all over Europe. Their success has traditionally been assessed using a plant community approach. However, population ecology can also be useful to assess restoration success and to understand underlying mechanisms. Methods_We took advantage of three calcareous grassland sites in Southern Belgium, where reference p...

  9. Biostratigraphic and morphometric analyses of specimens from the calcareous nannofossil genus Tribrachiatus

    Science.gov (United States)

    Self-Trail, Jean; Seefelt, Ellen L.; Shepherd, Claire L.; Martin, Victoria A.

    2017-01-01

    Biostratigraphic and morphometric analyses of calcareous nannofossil assemblages from one outcrop and two cored sections of lower Eocene sediments reveal the presence of two new species: Tribrachiatus lunatus sp. nov., and Tribrachiatus absidatus sp. nov. Differences between the new species and Tribrachiatus orthostylus are discussed. The first occurrence of the two new species is just below the calcareous nannofossil Zone NP11/NP12 boundary, close to the Chron 24r/23n boundary, and thus they are globally useful biostratigraphic markers.

  10. Calcar femorale grafting in the hemiarthroplasty of the hip for unstable inter trochanteric fractures.

    Science.gov (United States)

    Thakkar, Chandrashekar J; Thakkar, Savyasachi; Kathalgere, Rajshekhar T; Kumar, Malhar N

    2015-01-01

    The sliding screw-plate devices and cephalo-medullary nail devices have performed well in stable inter-trochanteric fractures in patients with reasonably good quality of bone. However, their suboptimal performance in comminuted fractures in the presence of osteoporotic bone has prompted many surgeons to consider bipolar hemiarthroplasty as the primary modality of management of comminuted inter-trochanteric fractures in elderly patients. However, long term stability of the hemiarthroplasty implant also may be compromised due to the presence of postero-medial bone loss at the area of the calcar. We have presented a simple and effective technique of calcar grafting by harvesting cortical bone strut from the neck of the fractured femur. A total of 34 patients with inter-trochanteric fractures of the femur were treated with calcar grafting. The mean age was 79.2 years. The graft was harvested from the calcar region of the head and neck fragment of the femur and wedged between the medial femoral cortex and medial edge of the prosthesis. The mean followup period was 54.5 months. In 32 of 34 (94%) patients in our series, the calcar graft healed well without dislodgement. There was graft resorption in two patients associated with subsidence of the implant and loosening. Calcar grafting using this technique provides stability to the implant in the presence of comminution and incorporates well in the majority of patients. Donor site morbidity of graft harvesting is also avoided.

  11. Influence of Cements Containing Calcareous Fly Ash as a Main Component Properties of Fresh Cement Mixtures

    Science.gov (United States)

    Gołaszewski, Jacek; Kostrzanowska-Siedlarz, Aleksandra; Ponikiewski, Tomasz; Miera, Patrycja

    2017-10-01

    The main goal of presented research was to examine usability of cements containing calcareous fly ash (W) from technological point of view. In the paper the results of tests concerning the influence of CEM II and CEM IV cements containing fly ash (W) on rheological properties, air content, setting times and plastic shrinkage of mortars are presented and discussed. Moreover, compatibility of plasticizers with cements containing fly ash (W) was also studied. Additionally, setting time and hydration heat of cements containing calcareous fly ash (W) were determined. In a broader aspect, the research contributes to promulgation of the possibility of using calcareous fly ash (W) in cement and concrete technology, what greatly benefits the environment protection (utilization of waste fly ash). Calcareous fly ash can be used successfully as the main component of cement. Cements produced by blending with processed fly ash or cements produced by interginding are characterized by acceptable technological properties. In respect to CEM I cements, cements containing calcareous fly ash worsen workability, decrease air content, delay setting time of mixtures. Cements with calcareous fly ash show good compatibility with plasticizers.

  12. Influence of calcareous deposit on corrosion behavior of Q235 carbon steel with sulfate-reducing bacteria

    Science.gov (United States)

    Zhang, Jie; Li, Xiaolong; Wang, Jiangwei; Xu, Weichen; Duan, Jizhou; Chen, Shougang; Hou, Baorong

    2017-12-01

    Cathodic protection is a very effective method to protect metals, which can form calcareous deposits on metal surface. Research on the interrelationship between fouling organism and calcareous deposits is very important but very limited, especially sulfate-reducing bacteria (SRB). SRB is a kind of very important fouling organism that causes microbial corrosion of metals. A study of the influence of calcareous deposit on corrosion behavior of Q235 carbon steel in SRB-containing culture medium was carried out using electrochemical impedance spectroscopy (EIS), scanning electron microscopy (SEM) and surface spectroscopy (EDS). The calcareous deposit was formed with good crystallinity and smooth surface under the gradient current density of -30 μA cm-2 in natural seawater for 72 h. Our results can help elucidate the formation of calcareous deposits and reveal the interrelationship between SRB and calcareous deposits under cathodic protection. The results indicate that the corrosion tendency of carbon steel was obviously affected by Sulfate-reducing Bacteria (SRB) metabolic activity and the calcareous deposit formed on the surface of carbon steel under cathodic protection was favourable to reduce the corrosion rate. Calcareous deposits can promote bacterial adhesion before biofilm formation. The results revealed the interaction between biofouling and calcareous deposits, and the anti-corrosion ability was enhanced by a kind of inorganic and organic composite membranes formed by biofilm and calcareous deposits.

  13. Calcareous microfossil-based orbital cyclostratigraphy in the Arctic Ocean

    Science.gov (United States)

    Marzen, Rachel; DeNinno, Lauren H.; Cronin, Thomas M.

    2016-01-01

    Microfaunal and geochemical proxies from marine sediment records from central Arctic Ocean (CAO) submarine ridges suggest a close relationship over the last 550 thousand years (kyr) between orbital-scale climatic oscillations, sea-ice cover, marine biological productivity and other parameters. Multiple paleoclimate proxies record glacial to interglacial cycles. To understand the climate-cryosphere-productivity relationship, we examined the cyclostratigraphy of calcareous microfossils and constructed a composite Arctic Paleoclimate Index (API) "stack" from benthic foraminiferal and ostracode density from 14 sediment cores. Following the hypothesis that API is driven mainly by changes in sea-ice related productivity, the API stack shows the Arctic experienced a series of highly productive interglacials and interstadials every ∼20 kyr. These periods signify minimal ice shelf and sea-ice cover and maximum marine productivity. Rapid transitions in productivity are seen during shifts from interglacial to glacial climate states. Discrepancies between the Arctic API curves and various global climatic, sea-level and ice-volume curves suggest abrupt growth and decay of Arctic ice shelves related to climatic and sea level oscillations.

  14. Soil degradation effect on biological activity in Mediterranean calcareous soils

    Science.gov (United States)

    Roca-Pérez, L.; Alcover-Sáez, S.; Mormeneo, S.; Boluda, R.

    2009-04-01

    Soil degradation processes include erosion, organic matter decline, compaction, salinization, landslides, contamination, sealing and biodiversity decline. In the Mediterranean region the climatological and lithological conditions, together with relief on the landscape and anthropological activity are responsible for increasing desertification process. It is therefore considered to be extreme importance to be able to measure soil degradation quantitatively. We studied soil characteristics, microbiological and biochemical parameters in different calcareous soil sequences from Valencia Community (Easter Spain), in an attempt to assess the suitability of the parameters measured to reflect the state of soil degradation and the possibility of using the parameters to assess microbiological decline and soil quality. For this purpose, forest, scrubland and agricultural soil in three soil sequences were sampled in different areas. Several sensors of the soil biochemistry and microbiology related with total organic carbon, microbial biomass carbon, soil respiration, microorganism number and enzyme activities were determined. The results show that, except microorganism number, these parameters are good indicators of a soil biological activity and soil quality. The best enzymatic activities to use like indicators were phosphatases, esterases, amino-peptidases. Thus, the enzymes test can be used as indicators of soil degradation when this degradation is related with organic matter losses. There was a statistically significant difference in cumulative O2 uptake and extracellular enzymes among the soils with different degree of degradation. We would like to thank Spanish government-MICINN for funding and support (MICINN, project CGL2006-09776).

  15. Fractionation of applied 32P labeled TSP in calcareous soils

    International Nuclear Information System (INIS)

    Asfary, A.F.; Al-Merey, R.; Al-Hameish, M.

    2005-01-01

    Calcareous dark brown red soil (calcixerollic xerochrept) from northern Syria was used in a pot experiment to study the fate of triple super phosphate fertilizer (TSP) with and without a crop (Local durum wheat (Triticum turgidum L. group durum (Desf)) c v. Bohouth). The soil received 17μg P/g soil of 32 P labeled TSP, and samples were collected from soils and plants at successive dates. Soil inorganic P was ≅94% of total soil P, with only 50-80% being soluble. Calcium phosphate compounds were the dominant fraction (≤68%) of the soluble inorganic soil P followed by occluded iron phosphate (≤48%) and all other fractions were ≤9%. Isotopic measurements showed that ≅ 50% of fertilizer P was nonexchangeable within 2 days, and TSP values in each fraction of soil inorganic P fluctuated in relatively similar proportions to the concentrations of fractions in soil. Available P (soil and TSP) in cropped soil was more than that in the uncropped soil, and plants had no effect on the distribution of P from fertilizer amongst the different P fractions. (author)

  16. Isotopegeochemical investigations and dating on minerals and fossils from sedimentary rocks: 1. Glauconites from Jura, Molasse and Helveticum (K-Ar, Rb-Sr), 2. 87Sr/86Sr-Isotope stratigraphy on marine and limnetic micro- and macro-fossils, 3. Primary minerals from tertiary bentonites and tuffs (U-Pb, K-Ar)

    International Nuclear Information System (INIS)

    Fischer, H.

    1988-01-01

    Glauconite investigations: the main problem in dating glauconites lies in the identification of authigenic minerals which have not been influenced by post-sedimentary processes. The age determination on glauconites from the three different tectonic units: the Jura mountains, the molasse basin and the Helvetic nappes, yield inconsistent results. Up to 35% too young K-Ar ''ages'' of glauconites from limestones from the Helvetic nappes can be traced to partial Ar loss caused by sediment-lithification and tectonic events. Sr-isotope stratigraphy: multiple analyses of recent samples from the Mediterranean Sea and from the North Atlantic show that the 87 Sr/ 86 Sr isotope ratios correspond well. In a stratigraphic ideal section from the Upper marine molasse a resolution of 206 Pb/ 238 U method zircons from the Fish Canyon Tuff were measured and yielded ages of 28.49±0.10, 24.46±0.11 and 28.46±0.13 Ma. These values correspond well with the published mean value of zircon and apatite fission track age of 28.4±0.7 Ma. Thus, the U-Pb method for dating young volcanic minerals seems to be suitable. However, the published mean value (''solid state age'') of Naeser et al. (1981) is higher than the published (''gas age'') mean value of 27.2±0.7 Ma based on biotite, sanidine, hornblende and plagioclase. (author) figs., tabs., refs

  17. Sodium hypochlorite oxidation of petroleum aliphatic contaminants in calcareous soils.

    Science.gov (United States)

    Picard, François; Chaouki, Jamal

    2016-02-01

    This research project investigated the sodium hypochlorite (NaClO) oxidation of aliphatic petroleum contaminants (C10-C50) in a calcareous soil (average 5473 ppm C10-C50, 15 wt% Ca), which had been excavated from a contaminated industrial site. The decontamination objective was to lower the C10-C50 concentration to 700 ppm. CO2 acidity was used in the project to boost the NaClO oxidation yield and seems to have played a role in desorbing the natural organic matter. The experimental conditions were a 2- to 16-h reaction time, at room temperature, with a 1 to 12.5 wt% NaClO oxidative solution and a fixed 2:1 solution-to-soil ratio. With a 3 wt% NaClO solution and with a CO2 overhead, the NaClO dosage requirement was maintained below 60 g NaClO/g of oxidized C10-C50 over the entire decontamination range. The strong chlorine smell remaining after the reaction was completed suggests that part of the NaClO requirement can be recycled. Except traces of chloroform, there were no regulation-listed organochloride contaminants detected on either the treated soil samples or leachates and the total count of chlorinated compounds in treated soil samples was below the detection limit of 250 mg/kg. The NaClO oxidation mechanism on aliphatic substrates might be triggered by transition metals, such as manganese, but no attempt has been made to investigate the oxidation mechanism. Further investigations would include a constant-fed NaClO system and other techniques to lower the required NaClO dosage. Copyright © 2015 Elsevier Ltd. All rights reserved.

  18. Firing transformations of an argentinean calcareous commercial clay

    Directory of Open Access Journals (Sweden)

    M. F. Serra

    2013-06-01

    Full Text Available Mineralogical transformations caused by firing are usually studied by XRD methods only semi-quantitatively. In this work the original mineral disappearance and the neo-mineralization were evaluated quantitatively. Furthermore an indirect non crystalline phase quantification was performed under 1100 ºC was also carried out using the quartz content as internal standard. This study specifically discusses the behavior of an Argentinean white calcareous earthenware commercial when subjected to traditional ceramic firing, besides the technological importance of this particular material, it acts as a model for other clay based ceramic materials. Materials were subjected to thermal treatments between 700 ºC and 1100 ºC. A preliminary sintering characterization was carried out by contraction and porosity evolution. Simultaneous thermogravimetric and differential thermal analysis (TG-DTA was carried out to elucidate the actual temperature at which the chemical changes occur. Finally, a quantitative analysis based on the Rietveld refinement of the X-ray diffraction patterns was performed to characterize the crystalline phases present in both the clay and in the materials obtained after different thermal treatments. The actual chemical reactions are proposed. The phases identified after firing at traditional working temperature (1040 ºC are quartz, plagioclase, and the Spinel type alumino-silicate, accompanied by the non-diffracting un-reacted metakaolin and some amount of amorphous glassy phase. At intermediate temperatures (900 ºC the presence of gehlenite was also detected. The carbonates (calcite and dolomite presence and decomposition were also evaluated and demonstrated to determine the sintering characteristics of this material.

  19. Identification of Nutrient Deficiencies at Calcareous Soils for Maize

    Directory of Open Access Journals (Sweden)

    Dedi Nursyamsi

    2010-09-01

    Full Text Available A pot experiment was conducted to identify nutrient deficiencies at calcareous soils for maize (Zea mays, L. in green house of Indonesian Soil Research Institute using top soil (0-20 cm samples taken from Bogor (Typic Hapludalfs and Blora (Typic Haplustalfs. The experiment used Randomized Completely Block Design, minus one test with 12 treatments and three replications, as well as maize of P21 variety as plant indicator. The results showed that use of N, P, K, Zn, Cu, Fe, and Mn fertilizers increased soil macro nutrients, i.e.: soil total-N, Olsen-P, HCl-P, and HCl-K, as well as soil micro nutrients, i.e.: soil DTPA-Zn, Cu, Fe, and Mn at both tested soils. Use of maize straw compost increased soil organic-C, total-N, HCl-K, and exchangeable Ca at Typic Hapludalfs and increased only soil organic-C and total-N at Typic Haplustalfs. Use of animal manure compost increased soil organic-C, exchangeable Ca and Mg, and CEC. Use of N, P, K, S, Zn, Cu, Fe, and Mn fertilizers increased each plant nutrients uptake at the soils. Use of both organic matters increased plant N, P, K, and Fe uptake at Typic Hapludalfs as well as increased only plant N, P, and K uptake at Typic Haplustalfs. Identification result showed that maize growth suffered from N, P, and K deficiencies at Typic Hapludalfs as well as N and P deficiencies at Typic Haplustalfs. Beside the nutrients, soil organic matter was also found out as limiting factor for maize growth in the soils.

  20. Dynamic shear stiffness and damping ratio of marine calcareous and siliceous sands

    Science.gov (United States)

    Javdanian, Hamed; Jafarian, Yaser

    2018-03-01

    Shear stiffness and damping ratio of two marine calcareous and siliceous sands were evaluated through an experimental program. Resonant column and cyclic triaxial experiments were conducted to measure the dynamic properties of the sands in small and large shear strain amplitudes. The tests were conducted under various initial stress-density conditions. The influence of effective confining pressure on the dynamic properties of the sands was assessed and compared in a preceding paper. It was shown that the calcareous sand has higher shear stiffness and lower damping ratio in comparison to the siliceous sand. In this note, the results are presented in more details and the dynamic behavior curves of the studied sands are compared with some available models, mostly developed based on the laboratory data of siliceous sands. This comparative study reveals that the previous models predict the dynamic properties of the calcareous sand in less precision than those of the siliceous sand.

  1. Effluent and gamma-irradiated digested sludge additions on calcareous soils

    International Nuclear Information System (INIS)

    Lee-Rodriguez, V.

    1978-01-01

    The long-term use of sewage effluent and the use of gamma-irradiated treated digested sewage sludge (RDSS) were studied under field and greenhouse conditions, respectively. The purpose of this investigation was to: (1) study the effect of long and short-term application of secondary sewage effluent and RDSS, respectively, on the buildup of iron and phytotoxicity problems on calcareous soils; (2) study the potential phytotoxicity of RDSS and observe the micronutrient fertilizer value of RDSS through three successive plantings on calcareous soil; (3) evaluate RDSS as a source of iron in a soil known to be severely iron-deficient

  2. Biostratigraphy of the Lower Cretaceous Schrambach Formation on the classical locality of Schrambachgraben (Northern Calcareous Alps, Salzburg Area)

    Czech Academy of Sciences Publication Activity Database

    Boorová, D.; Skupien, P.; Vašíček, Zdeněk

    2014-01-01

    Roč. 90, č. 1 (2014), s. 89-131 ISSN 1214-1119 Institutional support: RVO:68145535 Keywords : biostratigraphy * Schrambach and Rossfeld formations * Berriasian, Valanginian * calcareous and non-calcareous dinoflagellata * ammonites Subject RIV: DB - Geology ; Mineralogy Impact factor: 1.515, year: 2014 http://www.geology.cz/bulletin/fulltext/1479_Boorova_in_press.pdf

  3. Is succession in wet calcareous dune slacks affected by free sulfide?

    NARCIS (Netherlands)

    Adema, EB; van Gemerden, H; Grootjans, AP; Adema, Erwin B.; Grootjans, Ab P.; Rapson, G.

    Consequences of sulfide toxicity on succession in wet calcareous dune slacks were investigated. Sulfide may exert an inhibitory effect on dune slack plants, but several pioneer species exhibit ROL (Radial Oxygen Loss) and thereby protect themselves against free sulfide. Under oxic conditions free

  4. Sunlight-enhanced calcareous deposition on cathodic stainless steel in natural seawater

    Digital Repository Service at National Institute of Oceanography (India)

    Eashwar, M.; SathishKumar, P.; Ravishankar, R.; Subramanian, G.

    In replicate series of experiments in natural seawater, one in full darkness and the other in a 1:1 diurnal cycle with as little as 5 percent of natural solar illumination, sunlight promoted calcareous deposition on cathodic stainless steel surfaces...

  5. The potential of willow for remediation of heavy metal polluted calcareous urban soils

    DEFF Research Database (Denmark)

    Jensen, J K; Holm, P E; Nejrup, J

    2009-01-01

    Growth performance and heavy metal uptake by willow (Salix viminalis) from strongly and moderately polluted calcareous soils were investigated in field and growth chamber trials to assess the suitability of willow for phytoremediation. Field uptakes were 2-10 times higher than growth chamber...

  6. Geochemistry of calcareous sediments from the SW Carlsberg Ridge: Evidence for deeper carbonate compensation depth

    Digital Repository Service at National Institute of Oceanography (India)

    Valsangkar, A.B.; Ambre, N.V.

    Concentration of Mn, Fe, Ni, Co, Zn, Ca, Mg, K, Al, Si, Ti, P and CaCO sub(3) show wide range for the calcareous sediments from SW Carlsberg Ridge (CR). Compared with the average pelagic clays, the CR sediments are enriched by Mg, Ni, Co, and Zn...

  7. Community structure and palaeoecological implications of calcareous encrusters on artificial substrates across a Mexican Caribbean reef

    Science.gov (United States)

    Hepburn, L. J.; Blanchon, P.; Murphy, G.; Cousins, L.; Perry, C. T.

    2015-03-01

    Calcareous encrusters stabilize and bind reef framework and contribute significantly to reef function and biodiversity. Their calcareous skeletons have good preservation potential which, together with well-constrained habitat preferences, makes them useful indicators of past environmental conditions. However, our knowledge of environmental tolerances and spatial distribution trends of encrusters remains limited. Here, we determine the distributional trends and environmental tolerances of calcareous encrusters and delineate the relevance of particular species/genera for palaeoecological reconstructions. Artificial microhabitats were created to mimic exposed, partially cryptic, and cryptic habitats in various orientations for periods of 1 and 2 yr. Calcareous encruster coverage was high, especially in cryptic habitats (95 %), and clear successional trends were observed over time. Total encruster carbonate production was intermediate (range 72.8-476.3 g m-2 yr-1). Encruster species and growth morphology exhibited a defined zonation in response to reef sub-environment, microhabitat, and environmental factors such as light and wave exposure. Linear regression identified three coralline algae genera, as well as Homotrema rubrum, Planorbulina spp., and cemented bivalves as those most likely to occur in particular habitats. Therefore, the presence of these species may be used with greater confidence in distinguishing palaeomicroenvironments.

  8. Coniacian-maastrichtian calcareous nannofossil biostratigraphy and carbon-isotope stratigraphy in the Zagros Basin (Iran)

    DEFF Research Database (Denmark)

    Razmjooei, Mohammad Javad; Thibault, Nicolas; Kani, Anoshiravan

    2014-01-01

    , White Fall, Kingsdown, Michel Dean, Haven Brow, Horseshoe Bay, Buckle, Hawks Brow, Santonian/Campanian boundary (SCBE) and Campanian/Maastrichtian boundary (CMBE) events. Correlation to a recently proposed global δ13C stack for the Late Cretaceous points to a major mismatch of this compilation...... and calcareous nannofossil bio-horizons, and (2) their correlation between the Tethyan and Boreal realms....

  9. Calcareous nannofossils from the Boreal upper Campanian-Maastrichtian Chalk of Denmark

    DEFF Research Database (Denmark)

    Thibault, Nicolas Rudolph

    2010-01-01

    Boreal calcareous nannofossil assemblages have been documented from three sections in Denmark. from the Upper Campanian to Upper Maastrichtian (nannofossil zones UC16a(BP) to UC20d(BP)): the Stevns-1 borehole, next to the Cretaceous/Palaeogene boundary section of Stevns Klint, eastern Sjaelland...

  10. Laboratory Experiment Investigating the Impact of Ocean Acidification on Calcareous Organisms

    Science.gov (United States)

    Perera, Alokya P.; Bopegedera, A. M. R. P.

    2014-01-01

    The increase in ocean acidity since preindustrial times may have deleterious consequences for marine organisms, particularly those with calcareous structures. We present a laboratory experiment to investigate this impact with general, introductory, environmental, and nonmajors chemistry students. For simplicity and homogeneity, calcite was…

  11. Endolithic fungi from deep sea calcareous substrata: isolation and laboratory studies

    Digital Repository Service at National Institute of Oceanography (India)

    Raghukumar, C.; Raghukumar, S.; Sharma, S.; Chandramohan, D.

    substrata at 100 atm. in 25 days. This fungus was not capable of acid production on nutrient media in the presence of various carbon sources, nor did it produce proteases. The role of fungi in calcareous substrata in the sea is discussed with reference...

  12. Use of calcareous algae and monensin in Nellore cattle subjected to an abrupt change in diet

    Directory of Open Access Journals (Sweden)

    Roberta Ferreira Carvalho

    2016-04-01

    Full Text Available ABSTRACT: Additives are used in high concentrate diets to prevent metabolic disorders in cattle. This study was designed to evaluate the effect of calcium sources and monensin on the control of ruminal acidosis in Nellore cattle that were abruptly shifted to a high (92.3% concentrate diet. Eight cannulated steers were randomly assigned to two contemporary 4x4 Latin square. Treatments involved the addition of a calcium source, either limestone (LI or a product derived from calcareous algae (CA, to the basic diet with or without the presence of monensin. Calcareous alga (Lithothamnium calcareum is a natural and renewable product and a source of calcium carbonate. The quantity of added limestone, calcareous algae and monensin was 7.1g kg-1, 7.4g kg-1 and 30mg kg-1 DM, respectively. There was no effect of calcium source (P=0.607 or monensin (P=0.294 on feed intake or on the concentration of short chain fatty acids. Treatments with calcareous algae resulted in a higher mean ruminal pH (P=0.039, a shorter amount of time with the ruminal pH under 5.2 (P<0.001 and a better control of blood pH (P=0.006. Treatments with monensin also resulted in a shorter amount of time with the ruminal pH below 5.2 (P=0.023. Calcareous algae were shown to be effective in controlling adverse changes in the rumen and in blood variables for Nellore cattle that were subjected to an abrupt change to a high concentrate diet.

  13. Foraminiferans as food for Cephalaspideans (Gastropoda: Opisthobranchia), with notes on secondary tests around calcareous foraminiferans

    DEFF Research Database (Denmark)

    Cedhagen, Tomas

    1996-01-01

    species, Ammonia batavus and two agglutinating species, Ammoscalaria pseudospiralis and Ammotium cassis. The test (shell) material of the latter two species was sand grains (quartz). It was inferred that the gastropods avoid agglutinating foraminiferans as food. Many calcareous but not agglutinating......The food of four species of Cephalaspidea (Philine aperta, Philine denticulata, Philine scabra and Cylichna cylindracea) was studied in animals collected on silty clay bottoms at 20-35 m depth on the west coast of Sweden. The specimens were dissected. Only calcareous foraminiferans were found...... foraminiferans surround themselves with a “secondary test”, a cyst or covering of foreign particles around the test. This structure has earlier been called a “reproductive cyst” or “feeding cyst” in some species. “Secondary tests” are primarily connected with feeding, but might also be a preadaptation for other...

  14. Medial calcar of proximal humeral fracture as landmark in restoration of humeral length in case of hemiarthroplasty

    Czech Academy of Sciences Publication Activity Database

    Hromádka, R.; Kuběna, Aleš Antonín; Šmíd, Martin; Popelka, S.

    2014-01-01

    Roč. 35, č. 5 (2014), s. 473-479 ISSN 0930-1038 Institutional support: RVO:67985556 Keywords : Fracture of proximal humerus * Calcar of humeral fracture * Reconstruction of proximal humerus * Reconstruction of humeral length * Shoulder arthroplasty * Shoulder hemiarthroplasty Subject RIV: FJ - Surgery incl. Transplants Impact factor: 1.047, year: 2014 http://library.utia.cas.cz/separaty/2013/E/smid-medial calcar of proximal humeral fracture as landmark in restoration of humeral length in case of hemiarthroplasty.pdf

  15. Dried gamma-irradiated sewage solids use on calcareous soils: crop yields and heavy metals uptake

    International Nuclear Information System (INIS)

    McCaslin, B.D.; Sivinski, J.S.

    1980-01-01

    The fertilizer values of gamma-irradiated digested sewage solids (RDSS) and gamma-irradiated undigested sewage solids (RUSS) have been examined on calcareous soils. Previously published data from Sandia Laboratories have shown that approximately 1 mega-rad of gamma-irradiation effectively destroys pathogenic bacteria, parasites and plant seeds in dried sewage solids. Greenhouse experiments directly comparing gamma-irradiated and non-irradiated undigested and digested dried sewage solids as fertilizers indicate little or no effect of 1 mega-rad gamma radiation treatment on plant yield or plant-nutrient uptake and demonstrated considerable benefit from using sewage solids on calcareous soils. Plant response to undigested sewage solids was considerably greater than to digested sewage solids when applied at levels that were isonitrogenous. The calcareous soils in New Mexico typically range in pH from 7.5 to 9.0, limiting the plant-availability of many elements, especially heavy metals. Soils irrigated with sewage-effluent for 40 years demonstrated beneficial use of supplied plant-nutrients with no apparent increase in plant-uptake of heavy metals. RDSS applied to a calcareous soil low in plant-available iron increased plant growth in the greenhouse considerably more than treatments with equal amounts of nitrogen, phosphorus and iron applied as common fertilizer materials. Plant tissue concentrations of Fe, Zn, Mn and Cu showed that RDSS was a good source of these nutrients. Results also indicated that the total soluble salt concentration of the RDSS was the factor most limiting plant growth. Chromium, Cd, Ni and Pd plant-tissue concentrations were apparently not increased by RDSS treatments. (Auth.)

  16. Moessbauer study of the transformations occurring in egyptian alluvial and calcareous clays during firing

    International Nuclear Information System (INIS)

    Sallam, H.A.; Gomma, N.S.; El Meligy, W.M.; Eissa, N.A.

    1994-01-01

    Egyptian alluvial and calcareous clay samples, which are used in pottery production, were heated at different temperatures in air up to 1100 degree C. The physicochemical transformations were followed up and could be separated in two main stages; i) the dehydroxilation, of the clay mineral, stage for firing up to 700 degree C, ii) the second stage for firing at 900 degree C and higher. In the later stage the effect of calcium content was very pronounced. 2 figs

  17. A Study of Calcareous Deposits on Cathodically Protected Mild Steel in Artificial Seawater

    Directory of Open Access Journals (Sweden)

    Yuanfeng Yang

    2015-03-01

    Full Text Available Calcareous deposits were formed on steel under conditions of cathodic protection in artificial seawater at applied constant current densities ranging from 50 to 400 mA·m−2. The calcareous layers were characterized using a Field Emission Gun Scanning Electron Microscope (FEG SEM in conjunction with Energy Dispersive X-Ray Analysis (EDX, and Electrochemical Impedance Spectroscopy (EIS. At cathodic current densities of 50–100 mA·m−2 where corrosion was still occurring, a clear correlation existed between the iron containing corrosion product and the overlying magnesium hydroxide layer. This revealed that the mapping of magnesium rich areas on a steel surface can be used in the identification of local corrosion sites. At current densities of 150–200 mA·m−2, a layered deposit was shown to occur consisting of an inner magnesium-containing layer and an outer calcium-containing layer. At current densities of 300–400 mA·m−2, intense hydrogen bubbling through macroscopic pores in the deposits gave rise to cracking of the deposited film. Under such conditions deposits do not have a well-defined double layer structure. There is also preferential formation of magnesium-rich compounds near the steel surface at the early stages of polarisation and within the developing pores and cracks of calcareous deposits later on. Based on SEM/EDX investigation of calcareous depositions the impedance model was proposed and used to monitor in situ variations in steel corrosion resistance, and to calculate the thickness of formed deposits using the length of oxygen diffusion paths.

  18. Contrasting effects of ocean acidification on tropical fleshy and calcareous algae.

    Science.gov (United States)

    Johnson, Maggie Dorothy; Price, Nichole N; Smith, Jennifer E

    2014-01-01

    Despite the heightened awareness of ocean acidification (OA) effects on marine organisms, few studies empirically juxtapose biological responses to CO2 manipulations across functionally distinct primary producers, particularly benthic algae. Algal responses to OA may vary because increasing CO2 has the potential to fertilize photosynthesis but impair biomineralization. Using a series of repeated experiments on Palmyra Atoll, simulated OA effects were tested across a suite of ecologically important coral reef algae, including five fleshy and six calcareous species. Growth, calcification and photophysiology were measured for each species independently and metrics were combined from each experiment using a meta-analysis to examine overall trends across functional groups categorized as fleshy, upright calcareous, and crustose coralline algae (CCA). The magnitude of the effect of OA on algal growth response varied by species, but the direction was consistent within functional groups. Exposure to OA conditions generally enhanced growth in fleshy macroalgae, reduced net calcification in upright calcareous algae, and caused net dissolution in CCA. Additionally, three of the five fleshy seaweeds tested became reproductive upon exposure to OA conditions. There was no consistent effect of OA on algal photophysiology. Our study provides experimental evidence to support the hypothesis that OA will reduce the ability of calcareous algae to biomineralize. Further, we show that CO2 enrichment either will stimulate population or somatic growth in some species of fleshy macroalgae. Thus, our results suggest that projected OA conditions may favor non-calcifying algae and influence the relative dominance of fleshy macroalgae on reefs, perpetuating or exacerbating existing shifts in reef community structure.

  19. Calcareous nannoplankton and benthic foraminiferal assemblages from the Nazare Canyon (Portuguese continental margin): Preliminary results

    International Nuclear Information System (INIS)

    Guerreiro, C; Oliveira, A; Rodrigues, A; Rosa, F; Cachao, M; Fatela, F

    2009-01-01

    Submarine canyons are assumed to play an important role in oceanic/neritic circulation, marine productivity and sedimentary processes, acting as preferential conduits between the littoral and deep oceanic domain. Here we present first results of a comparative micropalaeontological study on calcareous nannoplankton and benthic foraminifera from surface sediments from the surroundings of the upper Nazare Canyon (Portuguese continental margin) and from the shelf north of the canyon. Regardless of the difficulty to distinguish taphonomical from (palaeo)ecological effects in such a complex and still poorly known marine system, the first results suggest that the canyon's hydro-sedimentary dynamic regime act as a prolongation of the shore/inner shelf hydrodynamic conditions towards west, preventing deposition and/or preservation of the smaller and fragile species of calcareous nannoplankton (e.g. E. huxleyi and G. ericsonii) and enhancing the record of the larger and more opportunistic ones (e.g. G. oceanica); and disturbing benthic foraminiferal productivity and/or diversity, or their preservation in the fossil record. Both calcareous nannoplankton and benthic foraminifera are more abundant off the canyon's domain, suggesting that its highly energetic thalweg conditions are probably filtering the fossil record in the sediment. Still, preliminary results suggest that the occurrence of persistent physical phenomena related with the canyon's morphology and proximity to the coast (e.g. solitary internal waves) may be locally promoting favourable conditions for calcareous nannoplankton, as shown by high values of nannoliths, chlorophyll a and 19' hexanoyloxyfucoxantine (unpublished data) north of the canyon's head. It is our goal to test this hypothesis in the near future by (a) studying multicore and surficial sediments from more recent surveys, and (b) calibrating the sediment results with water column data presently in process at the Institute of Oceanography (IO).

  20. Calcareous nannoplankton and benthic foraminiferal assemblages from the Nazare Canyon (Portuguese continental margin): Preliminary results

    Energy Technology Data Exchange (ETDEWEB)

    Guerreiro, C; Oliveira, A; Rodrigues, A [Division of Marine Geology, Portuguese Hydrographic Institute (IH), Rua das Trinas 49, 1249-093 Lisboa (Portugal); Rosa, F [CIACOMAR, Algarve University, Av. 16 de Julho s/n 8700-311 Olhao (Portugal); Cachao, M; Fatela, F [Geology Center and Geology Department, FCUL, Bloco C6, 3o Piso, sala 6.3.57 Campo Grande 1749-016 Lisboa (Portugal)], E-mail: catarina.guerreiro@hidrografico.pt

    2009-01-01

    Submarine canyons are assumed to play an important role in oceanic/neritic circulation, marine productivity and sedimentary processes, acting as preferential conduits between the littoral and deep oceanic domain. Here we present first results of a comparative micropalaeontological study on calcareous nannoplankton and benthic foraminifera from surface sediments from the surroundings of the upper Nazare Canyon (Portuguese continental margin) and from the shelf north of the canyon. Regardless of the difficulty to distinguish taphonomical from (palaeo)ecological effects in such a complex and still poorly known marine system, the first results suggest that the canyon's hydro-sedimentary dynamic regime act as a prolongation of the shore/inner shelf hydrodynamic conditions towards west, preventing deposition and/or preservation of the smaller and fragile species of calcareous nannoplankton (e.g. E. huxleyi and G. ericsonii) and enhancing the record of the larger and more opportunistic ones (e.g. G. oceanica); and disturbing benthic foraminiferal productivity and/or diversity, or their preservation in the fossil record. Both calcareous nannoplankton and benthic foraminifera are more abundant off the canyon's domain, suggesting that its highly energetic thalweg conditions are probably filtering the fossil record in the sediment. Still, preliminary results suggest that the occurrence of persistent physical phenomena related with the canyon's morphology and proximity to the coast (e.g. solitary internal waves) may be locally promoting favourable conditions for calcareous nannoplankton, as shown by high values of nannoliths, chlorophyll a and 19' hexanoyloxyfucoxantine (unpublished data) north of the canyon's head. It is our goal to test this hypothesis in the near future by (a) studying multicore and surficial sediments from more recent surveys, and (b) calibrating the sediment results with water column data presently in process at the Institute of

  1. Adsorption and desorption of Am(III) on calcareous soil and its parent material

    International Nuclear Information System (INIS)

    Li Weijuan; Zhang Fuming; Tao Zuyi

    2005-01-01

    The adsorption and desorption of Am(III) on a calcareous soil (sierozem) and its parent material (loess) were studied by batch technique. The molarities of the Am(III) aqueous solutions were less than 5 x 10 -9 mol/l. High adsorbability was found of Am(III) on the calcareous soil and its parent material. In order to decrease the adsorption and, hence, to investigate the adsorption characteristics properly, stable Eu 3+ as hold back carrier and analogue was added to the aqueous solution. The relative contributions of CaCO 3 , organic matter (OM) to the Am(III) adsorption on calcareous soil and its parent material were investigated. The adsorption and desorption isotherms of Am(III) on untreated soil and loess and the three kinds of treated soils and three kinds of treated loesses to remove CaCO 3 , OM and both CaCO 3 and OM were determined, respectively. It was found that all isotherms were linear, the average distribution coefficients (K d ) for the untreated soil and for the untreated loess were almost equal, while there was an obvious difference between the values of the average distribution coefficients (K d ) for the treated soil and the treated loess to remove CaCO 3 or OM. The adsorption-desorption hysteresis on the untreated and treated soils and loesses actually occurred and there was an obvious difference between the hysteresis coefficients on both the corresponding treated soil and loess. It can be concluded that the adsorbability of Am(III) on calcareous soil is similar to that on its parent material, and that the contributions of CaCO 3 and OM to the Am(III) adsorption by the untreated soil are different from those by the untreated parent material. (author)

  2. The potential of residues of furfural and biogas as calcareous soil amendments for corn seed production.

    Science.gov (United States)

    Zhao, Yunchen; Yan, Zhibin; Qin, Jiahai; Ma, Zhijun; Zhang, Youfu; Zhang, Li

    2016-04-01

    Intensive corn seed production in Northwest of China produced large amounts of furfural residues, which represents higher treatment cost and environmental issue. The broad calcareous soils in the Northwest of China exhibit low organic matter content and high pH, which led to lower fertility and lower productivity. Recycling furfural residues as soil organic and nutrient amendment might be a promising agricultural practice to calcareous soils. A 3-year field study was conducted to evaluate the effects of furfural as a soil amendment on corn seed production on calcareous soil with compared to biogas residues. Soil physical-chemical properties, soil enzyme activities, and soil heavy metal concentrations were assessed in the last year after the last application. Corn yield was determined in each year. Furfural residue amendments significantly decreased soil pH and soil bulk density. Furfural residues combined with commercial fertilizers resulted in the greater cumulative on soil organic matter, total phosphorus, available phosphorus, available potassium, and cation exchange capacity than that of biogas residue. Simultaneously, urease, invertase, catalase, and alkaline phosphatase increased even at the higher furfural application rates. Maize seed yield increased even with lower furfural residue application rates. Furfural residues resulted in lower Zn concentration and higher Cd concentration than that of biogas residues. Amendment of furfural residues led to higher soil electrical conductivity (EC) than that of biogas residues. The addition of furfural residues to maize seed production may be considered to be a good strategy for recycling the waste, converting it into a potential resource as organic amendment in arid and semi-arid calcareous soils, and may help to reduce the use of mineral chemical fertilizers in these soils. However, the impact of its application on soil health needs to be established in long-term basis.

  3. Relationships between nutrient composition of flowers and fruit quality in orange trees grown in calcareous soil

    OpenAIRE

    Pestana, M.; Beja, P.; Correia, P. J.; Varennes, Amarilis de; Faria, E. A.

    2005-01-01

    A field experiment was conducted in a commercial orange orchard (Citrus sinensis (L.) Osb. cv. ‘Valencia late’ grafted on Citrange Troyer) established on a calcareous soil in the south of Portugal, to investigate if flower analysis could be used to predict fruit quality. In April 1996, during full bloom, flowers were collected from 20 trees. In March 1997 the fruits were harvested and their quality evaluated. This procedure was repeated every year during three years. Principal Compon...

  4. Geochemistry and hydrology of a calcareous fen within the Savage Fen wetlands complex, Minnesota, USA

    Science.gov (United States)

    Komor, S.C.

    1994-01-01

    Savage Fen is a wetlands complex at the base of north-facing bluffs in the Minnesota River Valley. The complex includes 27.8 hectares of calcareous fen that host rare calciphile plants whose populations are declining in Minnesota. Water and sediment compositions in the calcareous fen were studied to gain a better understanding of the hydrologie System that sustains the rare vegetation. Groundwater in the fen is a calcium-magnesium-bicarbonate type with circumneutral pH values. The groundwater composition is the resuit of interactions among water, dissolved and gaseous carbon species, carbonates, and ion exchangers. Shallow groundwater is distinguished from deep groundwater by smaller concentrations of chloride, sulfate, magnesium, and sodium, and larger concentrations of calcium, bicarbonate, hydrogen sulfide, and ammonium. Magnesian calcite is the prevalent carbonate in unconsolidated sedimentary fill beneath the fen and is an important source and sink for dissolved calcium, magnesium, and inorganic carbon. Calcite concentrations just below the water table are small because aerobic and anaerobic oxidation of organic matter increase the partial pressure of carbon dioxide (PCO2), decrease pH, and cause calcite to dissolve. Thick calcite accumulations just above the water table, in the root zone of calciphile plants, result from water table fluctuations and attendant changes in PCO2. Groundwater beneath Savage Fen recharges in lakes and ponds south of the fen and upwells to the surface within the fen. Water at the water table is a mixture of upwelling groundwater and water near the surface that flows downslope from higher elevations in the fen. Changes in oxygen and hydrogen isotope compositions of shallow groundwater indicate that the proportion of upwelling groundwater in shallow groundwater decreases downgradient in the calcareous fen. Encroachment of reed grasses into the calcareous fen may reflect human-caused disturbances in the recharge area.

  5. Contrasting effects of ocean acidification on tropical fleshy and calcareous algae

    Directory of Open Access Journals (Sweden)

    Maggie Dorothy Johnson

    2014-05-01

    Full Text Available Despite the heightened awareness of ocean acidification (OA effects on marine organisms, few studies empirically juxtapose biological responses to CO2 manipulations across functionally distinct primary producers, particularly benthic algae. Algal responses to OA may vary because increasing CO2 has the potential to fertilize photosynthesis but impair biomineralization. Using a series of repeated experiments on Palmyra Atoll, simulated OA effects were tested across a suite of ecologically important coral reef algae, including five fleshy and six calcareous species. Growth, calcification and photophysiology were measured for each species independently and metrics were combined from each experiment using a meta-analysis to examine overall trends across functional groups categorized as fleshy, upright calcareous, and crustose coralline algae (CCA. The magnitude of the effect of OA on algal growth response varied by species, but the direction was consistent within functional groups. Exposure to OA conditions generally enhanced growth in fleshy macroalgae, reduced net calcification in upright calcareous algae, and caused net dissolution in CCA. Additionally, three of the five fleshy seaweeds tested became reproductive upon exposure to OA conditions. There was no consistent effect of OA on algal photophysiology. Our study provides experimental evidence to support the hypothesis that OA will reduce the ability of calcareous algae to biomineralize. Further, we show that CO2 enrichment either will stimulate population or somatic growth in some species of fleshy macroalgae. Thus, our results suggest that projected OA conditions may favor non-calcifying algae and influence the relative dominance of fleshy macroalgae on reefs, perpetuating or exacerbating existing shifts in reef community structure.

  6. The potential of willow for remediation of heavy metal polluted calcareous urban soils

    International Nuclear Information System (INIS)

    Jensen, Julie K.; Holm, Peter E.; Nejrup, Jens; Larsen, Morten B.; Borggaard, Ole K.

    2009-01-01

    Growth performance and heavy metal uptake by willow (Salix viminalis) from strongly and moderately polluted calcareous soils were investigated in field and growth chamber trials to assess the suitability of willow for phytoremediation. Field uptakes were 2-10 times higher than growth chamber uptakes. Despite high concentrations of cadmium (≥80 mg/kg) and zinc (≥3000 mg/kg) in leaves of willow grown on strongly polluted soil with up to 18 mg Cd/kg, 1400 mg Cu/kg, 500 mg Pb/kg and 3300 mg Zn/kg, it is unsuited on strongly polluted soils because of poor growth. However, willow proved promising on moderately polluted soils (2.5 mg Cd/kg and 400 mg Zn/kg), where it extracted 0.13% of total Cd and 0.29% of the total Zn per year probably representing the most mobile fraction. Cu and Pb are strongly fixed in calcareous soils. - Willow is suited for remediation of moderately heavy metal polluted calcareous soils

  7. Fate and Distribution of Heavy Metals in Wastewater Irrigated Calcareous Soils

    Science.gov (United States)

    Stietiya, Mohammed Hashem; Duqqah, Mohammad; Udeigwe, Theophilus; Zubi, Ruba; Ammari, Tarek

    2014-01-01

    Accumulation of heavy metals in Jordanian soils irrigated with treated wastewater threatens agricultural sustainability. This study was carried out to investigate the environmental fate of Zn, Ni, and Cd in calcareous soils irrigated with treated wastewater and to elucidate the impact of hydrous ferric oxide (HFO) amendment on metal redistribution among soil fractions. Results showed that sorption capacity for Zarqa River (ZR1) soil was higher than Wadi Dhuleil (WD1) soil for all metals. The order of sorption affinity for WD1 was in the decreasing order of Ni > Zn > Cd, consistent with electrostatic attraction and indication of weak association with soil constituents. Following metal addition, Zn and Ni were distributed among the carbonate and Fe/Mn oxide fractions, while Cd was distributed among the exchangeable and carbonate fractions in both soils. Amending soils with 3% HFO did not increase the concentration of metals associated with the Fe/Mn oxide fraction or impact metal redistribution. The study suggests that carbonates control the mobility and bioavailability of Zn, Ni, and Cd in these calcareous soils, even in presence of a strong adsorbent such as HFO. Thus, it can be inferred that in situ heavy metal remediation of these highly calcareous soils using iron oxide compounds could be ineffective. PMID:24723833

  8. The small-scale species mobility in calcareous grasslands - example from southern Poland

    Directory of Open Access Journals (Sweden)

    Wojciech Bąba

    2011-01-01

    Full Text Available In this paper I use the different measures of species mobility to describe the fine small-scale dynamics of calcareous grassland built mainly by perennial species and developed in the highly heterogeneous habitat of calcareous rocks. The community showed the low dynamics on a plot-scale (100 m2 and a high one on the scale of 1 m2. However, the studied species differed greatly in calculated indices: turnover rate, (T; 6-64, residence time (RT; 0.5-21.8 y and carousel time (CT; 4-420 y as well as the observed tendency to persistence on the spots (PERSIST and their re-colonisation (AGAIN. This allowed to distinguish the three groups of species: (1 "core species" characterized by high frequency and low T and high CT and RT values, which determine the low dynamics of a community on the plot scale, (2 species with intermediate mobility rate and (3 the group with high mobility rate. The observed cumulative frequencies of all the studied species (CFobs were much lower than expected under the random re-assignation model (CFRR. Moreover, they were also lower than those predicted by random immigration model (CFRI. The results showed that the "complex carousel" model rather than "single carousel" one explained better the small-scale dynamics of calcareous grasslands.

  9. Cathodic behaviour of stainless steel in coastal Indian seawater: calcareous deposits overwhelm biofilms.

    Science.gov (United States)

    Eashwar, M; Subramanian, G; Palanichamy, S; Rajagopal, G; Madhu, S; Kamaraj, P

    2009-01-01

    Type-316 stainless steel (SS) was investigated as the cathode in galvanic couples in full-strength seawater from the Gulf of Mannar on the southeast coast of India. Tests were devised to examine the impact of SS cathodes on anode materials with or without the accrual of marine biofilms. Biofilmed SS cathodes significantly enhanced the rate of corrosion of nickel, causing noble shifts in the couple potentials. With mild steel and zinc as the anodes, calcareous deposits developed quite rapidly on the SS cathodes and led to a significant reduction of bacterial numbers. The calcareous deposits also caused substantial reduction of galvanic corrosion rates for mild steel, whereas there was no difference for zinc. The deposits were identified by XRD as essentially carbonates, oxides and hydroxides of calcium and magnesium. Potentiodynamic polarization performed on the actual couples after disconnection and equilibration provided reasonable interpretations of the galvanic corrosion trends. Data from this work suggest that a potential of about -0.70 V vs. saturated calomel electrode (SCE) should provide optimum protection of SS in warmer, full-strength seawater that supports the precipitation of calcareous deposits. The criterion commonly recommended for temperate conditions of lower water temperature and estuarine waters of lower alkalinity is -1.0 V (SCE).

  10. INFLUENCE OF SILICEOUS AND CALCAREOUS FLY-ASHES ON PROPERTIES OF CEMENT MORTARS

    Directory of Open Access Journals (Sweden)

    Gabriela Monika Rutkowska

    2016-09-01

    Full Text Available Care of the environment in accordance with the principles of sustainable development introduces the possibility and need for waste recycling. Construction and building industries have the greatest potential for reuse of waste. The article presents the results of investigations of cement mortars – tests of compressive and tensile strength after 28 and 56 days of curing – for normative mortars and mortars containing fly ashes – calcareous and siliceous ash – in their composition. To make the samples, the Portland cement CEM I 32,5 R, 42,5R and natural aggregate with graining of 0–2 mm were used. Concrete with siliceous and calcareous admixtures was made in six lots where the ash was added in the quantity of 2%, 5%, 10% of the cement mass or the 2%, 5%, 10% of cement was replaced by ashes. After the tests, it was stated that the siliceous fly-ash admixture increases the compressive and bending strength in comparison to the mortars with the calcareous ash admixtures.

  11. Fate and Distribution of Heavy Metals in Wastewater Irrigated Calcareous Soils

    Directory of Open Access Journals (Sweden)

    Mohammed Hashem Stietiya

    2014-01-01

    Full Text Available Accumulation of heavy metals in Jordanian soils irrigated with treated wastewater threatens agricultural sustainability. This study was carried out to investigate the environmental fate of Zn, Ni, and Cd in calcareous soils irrigated with treated wastewater and to elucidate the impact of hydrous ferric oxide (HFO amendment on metal redistribution among soil fractions. Results showed that sorption capacity for Zarqa River (ZR1 soil was higher than Wadi Dhuleil (WD1 soil for all metals. The order of sorption affinity for WD1 was in the decreasing order of Ni > Zn > Cd, consistent with electrostatic attraction and indication of weak association with soil constituents. Following metal addition, Zn and Ni were distributed among the carbonate and Fe/Mn oxide fractions, while Cd was distributed among the exchangeable and carbonate fractions in both soils. Amending soils with 3% HFO did not increase the concentration of metals associated with the Fe/Mn oxide fraction or impact metal redistribution. The study suggests that carbonates control the mobility and bioavailability of Zn, Ni, and Cd in these calcareous soils, even in presence of a strong adsorbent such as HFO. Thus, it can be inferred that in situ heavy metal remediation of these highly calcareous soils using iron oxide compounds could be ineffective.

  12. Activity and diversity of methane-oxidizing bacteria in glacier forefields on siliceous and calcareous bedrock

    Directory of Open Access Journals (Sweden)

    P. A. Nauer

    2012-06-01

    Full Text Available The global methane (CH4 cycle is largely driven by methanogenic archaea and methane-oxidizing bacteria (MOB, but little is known about their activity and diversity in pioneer ecosystems. We conducted a field survey in forefields of 13 receding Swiss glaciers on both siliceous and calcareous bedrock to investigate and quantify CH4 turnover based on soil-gas CH4 concentration profiles, and to characterize the MOB community by sequencing and terminal restriction fragment length polymorphism (T-RFLP analysis of pmoA. Methane turnover was fundamentally different in the two bedrock categories. Of the 36 CH4 concentration profiles from siliceous locations, 11 showed atmospheric CH4 consumption at concentrations of ~1–2 μL L−1 with soil-atmosphere CH4 fluxes of –0.14 to –1.1 mg m−2 d−1. Another 11 profiles showed no apparent activity, while the remaining 14 exhibited slightly increased CH4 concentrations of ~2–10 μL L−1 , most likely due to microsite methanogenesis. In contrast, all profiles from calcareous sites suggested a substantial, yet unknown CH4 source below our sampling zone, with soil-gas CH4 concentrations reaching up to 1400 μL L−1. Remarkably, most soils oxidized ~90 % of the deep-soil CH4, resulting in soil-atmosphere fluxes of 0.12 to 31 mg m−2 d−1. MOB showed limited diversity in both siliceous and calcareous forefields: all identified pmoA sequences formed only 5 operational taxonomic units (OTUs at the species level and, with one exception, could be assigned to either Methylocystis or the as-yet-uncultivated Upland Soil Cluster γ (USCγ. The latter dominated T-RFLP patterns of all siliceous and most calcareous samples, while Methylocystis dominated in 4 calcareous samples. Members of Upland Soil

  13. Entomopathogenic fungi-based mechanisms for improved Fe nutrition in sorghum plants grown on calcareous substrates.

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    Silvia Raya-Díaz

    Full Text Available Although entomopathogenic fungi (EPF are best known for their ability to protect crops against insect pests, they may have other beneficial effects on their host plants. These effects, which include promoting plant growth and conferring resistance against abiotic stresses, have been examined in recent years to acquire a better understanding of them. The primary purposes of the present study were (i to ascertain in vitro whether three different strains of EPF (viz., Metarhizium, Beauveria and Isaria would increase the Fe bioavailability in calcareous or non-calcareous media containing various Fe sources (ferrihydrite, hematite and goethite and (ii to assess the influence of the EPF inoculation method (seed dressing, soil treatment or leaf spraying on the extent of the endophytic colonization of sorghum and the improvement in the Fe nutrition of pot-grown sorghum plants on an artificial calcareous substrate. All the EPFs studied were found to increase the Fe availability during the in vitro assay. The most efficient EPF was M. brunneum EAMa 01/58-Su, which lowered the pH of the calcareous medium, suggesting that it used a different strategy (organic acid release than the other two fungi that raised the pH of the non-calcareous medium. The three methods used to inoculate sorghum plants with B. bassiana and M. brunneum in the pot experiment led to differences in re-isolation from plant tissues and in the plant height. These three inoculation methods increased the leaf chlorophyll content of young leaves when the Fe deficiency symptoms were most apparent in the control plants (without fungal inoculation as well as the Fe content of the above-ground biomass in the plants at the end of the experiment. The total root lengths and fine roots were also increased in response to fungal applications with the three inoculation methods. However, the soil treatment was the most efficient method; thus, its effect on the leaf chlorophyll content was the most

  14. Isolation and identification of ferric reducing bacteria and evaluation of their roles in iron availability in two calcareous soils

    Science.gov (United States)

    Ghorbanzadeh, N.; Lakzian, A.; Haghnia, G. H.; Karimi, A. R.

    2014-12-01

    Iron is an essential element for all organisms which plays a crucial role in important biochemical processes such as respiration and photosynthesis. Iron deficiency seems to be an important problem in many calcareous soils. Biological dissimilatory Fe(III) reduction increases iron availability through reduction of Fe(III) to Fe(II). The aim of this study was to isolate, identify and evaluate some bacterial isolates for their abilities to reduce Fe(III) in two calcareous soils. Three bacterial isolates were selected and identified from paddy soils by using 16S rRNA amplification and then inoculated to sterilized and non-sterilized calcareous soils in the presence and absence of glucose. The results showed that all isolates belonged to Bacillus genus and were capable of reducing Fe(III) to Fe(II) in vitro condition. The amount of Fe(III) reduction in sterilized calcareous soils was significantly higher when inoculated with PS23 isolate and Shewanella putrefaciens ( S. putrefaciens) (as positive control) compared to PS16 and PS11 isolates. No significant difference was observed between PS11 and PS16 isolates in the presence of indigenous microbial community. The results also revealed that glucose had a significant effect on Fe(III) reduction in the examined calcareous soil samples. The amount of Fe(III) reduction increased two-fold when soil samples were treated with glucose and inoculated by S. putrefaciens and PS23 in non-sterilized soils.

  15. Calcareous forest seepages acting as biodiversity hotspots and refugia for woodland snail faunas

    Science.gov (United States)

    Horsák, Michal; Tajovská, Eva; Horsáková, Veronika

    2017-07-01

    Land-snail species richness has repeatedly been found to increase with the increasing site calcium content and humidity. These two factors, reported as the main drivers of land-snail assemblage diversity, are also among the main habitat characteristics of calcareous seepages. Here we explore local species richness and compositional variation of forest spring-fed patches (i.e. seepages), to test the hypothesis that these habitats might act as biodiversity hotspots and refugia of regional snail faunas. In contrast to treeless spring fens, only little is known about land snail faunas inhabiting forest seepages. Studying 25 isolated calcareous forest seepages, evenly distributed across the White Carpathians Protected Landscape Area (SE Czech Republic), we found that these sites, albeit spatially very limited, can harbour up to 66% of the shelled land-snail species known to occur in this well-explored protected area (in total 83 species). By comparing land snail assemblages of the studied seepages with those occurring in the woodland surroundings of each site as well as those previously sampled in 28 preserved forest sites within the study area, we found the seepages to be among the most species rich sites. Although the numbers of species did not statistically differ among these three systems, we found highly significant differences in species composition. Seepage faunas were composed of many species significantly associated with spring sites, in contrast to the assemblages of both surrounding and preserved forest sites. Our results highly support the hypothesis that calcareous forest seepages might serve as refugia and biodiversity hotspots of regional land snail faunas. Protection of these unique habitats challenges both conservation plans and forest management guidelines as they might act as sources for the recolonization and restoration of forest snail assemblages particularly in areas impoverished by harvesting and clearcutting.

  16. EARLY TO LATE OLIGOCENE CALCAREOUS NANNOFOSSIL BIOEVENTS IN THE MEDITERRANEAN (UMBRIA-MARCHE BASIN, CENTRAL ITALY

    Directory of Open Access Journals (Sweden)

    PATRIZIA MAIORANO

    2006-07-01

    Full Text Available Calcareous nannofossil assemblages have been investigated by means of quantitative analyses in three Oligocene pelagic sections located in the Umbria-Marche Apennines (Central Italy. The studied sections mainly consist of marly limestones and marls belonging to the Scaglia Cinerea Formation, and include the interval between NP23 and NP25 representing a time interval of about 3.5 Ma. Biostratigraphic resolution is extremely low and only two standard bioevents are known, which are the FO of Sphenolithus ciperoensis and the LO of Sphenolithus distentus. The distribution patterns of poorly known or recently described calcareous nannofossils provided a valuable tool for improving the current biostratigraphic framework. The studied interval is characterized by significant changes in the calcareous nannofossil assemblages and by several extinction events. The last occurrence (LO and/or the last common occurrence (LCO here proposed are: the LO of Sphenolithus akropodus, the LO of Reticulofenestra circus, the LCO of Helicosphaera ethologa, the LCO of Helicosphaera compactathe LO of Discoaster tanii nodifer. The reversal in abundance between Sphenolithus predistentus and S. distentus provided an additional biostratigraphic constraint at the NP23-NP24 transition. In addition biometric criteria enabled the recognition of the first common occurrence (FCO of Cyclicargolithus abisectus > 12 mm as potential bioevent within NP24. The quantitative distribution of Sphenolithus distentus suggests to rely on the LCO of the species rather than on the LO, for the identification of NP24-NP25 boundary. The identified bioevents is a first step towards the improvement of the present Mediterranean biostratigraphic framework of the Oligocene geological record. A preliminary correlation of the bioevents to the Geomagnetic Polarity Time Scale is presented.

  17. Reducing As availability in calcareous soils using nanoscale zero valent iron.

    Science.gov (United States)

    Azari, Prisa; Bostani, Abdol Amir

    2017-09-01

    Different methods, including the use of nanoscale zero-valent iron (NZVI), have been used to treat arsenic (As)-contaminated environments, with much less data on the use of NZVI in arsenic-calcareous-polluted soils. Accordingly, two different experiments were conducted to investigate the effects of NZVI on the removal of As from three different calcareous-polluted soils. In the first experiment, the effects of soil type (differing in the rate of clay particles and organic carbon including S1 (8.0 and 0.05%), S2 (20 and 0.2%), and S3 (20.5 and 0.8%)) and NZVI concentration (0, 50, and 100 g kg -1 of dry soil) on the removal of As extractable with distilled water were evaluated using a factorial design with three replicates. In the second experiment, the NZVI concentrations were reduced to 0, 2.5, 5.0, and 25 g kg -1 , and the NZVI contact time (0.5, 48, 96, 192, 384, and 768 h) was also tested. The analysis of variance in both experiments indicated the significant effects (P soils, with increasing NZVI concentration and contact time, the concentration of available As in the solution phase significantly decreased (P = 0.01). S3, due to a higher rate of organic matter, was less responsive to the NZVI treatments than the other soils. The effectiveness of the nanoremediation method, tested in this research work, on the stabilization of As in calcareous soils, is verified.

  18. Potential use of calcareous mudstones in low hydraulic conductivity earthen barriers for environmental applications.

    Science.gov (United States)

    Musso, T B; Francisca, F M; Musso, T B; Musso, T B

    2013-01-01

    Earthen layers play a significant role in isolating contaminants in the subsurface, controlling the migration of contaminant plumes, and as landfill liners and covers. The physical, chemical and mineralogical properties of three calcareous mudstones from the Jagüel and Roca formations in North Patagonia, Argentina, are evaluated to determine their potential for the construction of liners. These mudstones were deposited in a marine environment in the Upper Cretaceous-Paleocene. The tested specimens mainly comprise silt and clay-sized particles, and their mineralogy is dominated by a smectite/illite mixed layer (70-90% Sm) and calcite in smaller proportion. Powdered mudstone samples have little viscosity and swelling potential when suspended in water. The hydraulic conductivity of compacted mudstones and sand-mudstone mixtures is very low (around 1-3 x 10(-10) m/s) and in good agreement with the expected hydraulic behaviour of compacted earthen layers. This behaviour can be attributed to the large amount of fine particles, high specific surface and the close packing of particles as confirmed by scanning electron microscope analysis. The tested materials also show a high cation exchange capacity (50-70 cmol/kg), indicating a high contaminant retardation capability. The calcareous mudstones show satisfactory mineralogical and chemical properties as well as an adequate hydraulic behaviour, demonstrating the potential use of these materials for the construction of compacted liners for the containment of leachate or as covers in landfills. These findings confirm the potential usage of marine calcareous mudstones as a low-cost geomaterial in environmental engineering projects.

  19. Relationships of 137Cs inventory with magnetic measures of calcareous soils of hilly region in Iran

    International Nuclear Information System (INIS)

    Ayoubi, Shamsollah; Ahmadi, Mohamamd; Abdi, Mohammad Reza; Abbaszadeh Afshar, Farideh

    2012-01-01

    Erosion is a natural process, but it has been dramatically increased by human activities; and this adversely influences soil productivity and environmental quality. For quantification of soil erosion, several techniques including the use of Cs-137 have been employed. This study was conducted to explore the relationships of Cs-137 inventory with magnetic properties in calcareous soils in western Iran. Ten transects were selected in the hilly region in Chelgerd district of Iran. Soil samples from 0 to 30 and 30–50 cm depths were collected from fifty points to determine Cs-137 inventory, magnetic measures and selected physico-chemical properties (in total there were 100 soil samples). The results showed that simple mass balance model (SMBM) estimated a gross erosion rate of 29.6 t ha −1 yr −1 and a net soil deposition of 21.8 t ha −1 yr −1 ; hence, a net soil loss of 9.6 t ha −1 yr −1 and a sediment delivery ratio of 31.4%. Simple linear regression and non-linear regression analysis showed that mass magnetic susceptibility (χ lf ) explained only 33.64% and 45% of variability in Cs-137 in the transects studied. The results of multiple linear regression analysis of 137 Cs with magnetic parameters and physico-chemical properties indicated that extractable potassium and χ lf explained approximately 61% of the total variability in 137 Cs in the area studied. Overall, the results suggest that further research is needed for the use of magnetic characteristics as an alternative technique in place Cs-137 methodology for calcareous soils. - Highlights: ► Simple linear regression mass magnetic susceptibility (χ L ) explained only 33.64 % of Cs-137 variability. ► Non-linear regression model explained 45% of variability in Cs-137 in the transects studied. ► Magnetic Susceptibility measures could not directly be used in calcareous soils to evaluate soil redistribution. ► Magnetic characteristics as an alternative technique instead of Cs-137 in calcareous

  20. Palaeoenvironmental changes in the Late Triassic (Rhaetian) of the Northern Calcareous Alps

    DEFF Research Database (Denmark)

    Mette, Wolfgang; Elsler, Armin; Korte, Christoph

    2012-01-01

    in the Kössen Formation and determine their significance for environmental and climatic conditions in the Rhaetian sea of the Eiberg Basin (Northern Calcareous Alps). For this purpose 60 δ 18O measurements on 43 articulate brachiopods samples from 8 different horizons were carried out. The results indicate...... to the lowest unit 3 of the Eiberg Member that parallels oxygen isotopes. This positive δ 13C trend is interrupted by a sudden ~1.5‰ negative excursion in the late Rhaetian (Late Rhaetian Event), a time span when the oxygen isotopes remain heavy....

  1. Mining and geologic characterization of calcareous resources for the cement industry in Uruguay

    International Nuclear Information System (INIS)

    De Santana, H.; Veroslavsky, G.; Sanchez, L.; Rossini, C.; Aubet, N.; Loureiro, J.; Gutierrez, L.

    2000-01-01

    The main objective of this work was the study of geological and mining potential that Uruguay has on limestone rocks rich in calcium and poor in magnesium and silica, which are considered primary requirements suitable for the manufacture of cement. The results obtained allow defining four major regions of the country that although do not include all occurrences of calcareous rocks, they do not constitute the most important areas concerning: rock quality, higher volumes and improved extraction possibilities. The areas are: Queguay, Minas, Carape and Treinta y tres

  2. Biot's coefficient as an indicator of strength and porosity reduction: Calcareous sediments from Kerguelen Plateau

    DEFF Research Database (Denmark)

    Alam, Mohammad Monzurul; Borre, Mai Kirstine; Fabricius, Ida Lykke

    2010-01-01

    β to fall, even when porosity remains constant. Biot's coefficient correlates with strength-indicating properties: compressional and shear modulus, oedometer modulus, yield strength, strain from direct loading and creep strain. Our data indicate that β may be used for predicting the diagenetic...... Biot's coefficient, β. In calcareous ooze, β is one. Mechanical compaction reduces porosity, but only leads to a minor decrease in β. Recrystallization renders particles smoother, but does not lead to reduction in β unless it gives rise to pore stiffening cementation. Pore stiffening cementation causes...

  3. The calcareous mires in South-East Poland are home to two rare Anthracoidea species

    Directory of Open Access Journals (Sweden)

    Marcin Piątek

    2013-12-01

    Full Text Available The new collections of Anthracoidea buxbaumii Kukkonen on Carex buxbaumii Wahlenb. and Anthracoidea hostianae B.Lindeb. ex Nannf. on Carex lepidocarpa Tausch recorded in the calcareous mires in South-East Poland are described, illustrated and discussed. The holotype of the latter smut is also re-examined, described and illustrated in detail. Anthracoidea buxbaumii is reported for the second time from Poland on a new host plant. Anthracoidea hostianae is new to Poland. The variability of spore sizes of both species is discussed. The conspecificity of Anthracoidea buxbaumii and A. hostianae suggested in the literature is analyzed.

  4. Dried gamma-irradiated sewage solids use on calcareous soils: crop yeilds and heavy metals uptake

    International Nuclear Information System (INIS)

    McCaslin, B.D.; Sivinski, J.S.

    1979-01-01

    Experiments designed to examine gamma-radiation effects on extractable and plant-available sludge elements and to examine the response of crops to sludge applications on two typical, calcareous soils in New Mexico are summarized. Information has been given indicating that the radiation process of reducing pathogens in sewage products being developed by Sandia Laboratories, does not significantly increase the chemical extractability and plant uptake of a broad range of nutrients and heavy metals. However, radiation treatment greatly facilitates handling sewage for experimentation, because pathogen contamination precautions are eliminated and weed seeds killed. Studies on the effects of sludge irradiation on plant nutrient uptake revealed no concentration increases, agreeing with results presented herein. Sewage products may have special potential for use on calcareous soils, such as in New Mexico. For instance, in New Mexico the lack of potassium in sewage products is not a problem and the naturally high pH of New Mexico soil greatly reduces plant availability of many problem heavy metals. Dramatic increases in yield are typified by the greenhouse and field results presented herein, especially for the known micronutrient deficient soils of New Mexico. Results indicate that sewage sludge is an excellent Zn and Fe fertilizer. More research needs to be done before the economics of sludge application can be calculated and more field information is needed before irradiated sewage products are used indiscriminately

  5. Fragmentation, Fusion, and Genetic Homogeneity in a Calcareous Sponge (Porifera, Calcarea).

    Science.gov (United States)

    Padua, André; Leocorny, Pedro; Custódio, Márcio Reis; Klautau, Michelle

    2016-06-01

    Sessile marine invertebrates living on hard substrata usually present strategies such as size variations, longer life spans, fragmentation and fusion to occupy and compete for space. Calcareous sponges are usually small and short-lived, and some species are known to undergo frequent fragmentation and fusion events. However, whether fusion occurs only between genetically identical individuals remains unclear. We investigated the occurrence of chimaeras in the calcareous sponge Clathrina aurea by following the dynamics of fragmentation and fusion of 66 individuals in the field for up to 18 months and determined size variations and the life span of each individual. Microsatellites were used to determine whether fusion events occur among genetically different individuals. Growth and shrinkage of individuals were frequently observed, showing that size cannot be associated with age in C. aurea. The life span of the species ranged from 1 to 16 months (mean: 4.7 months). Short life spans and variable growth rates have been observed in other species of the class Calcarea. Fragmentation and fusion events were observed, but fusion events always occurred between genetically identical individuals, as has been suggested by graft experiments in adult Demospongiae and other Calcarea. These results suggest that at least C. aurea adults may have some mechanism to avoid chimaerism. © 2016 Wiley Periodicals, Inc.

  6. DRY CALCAREOUS GRASSLAND COMMUNITIES (FILIPENDULA VULGARIS-HELICTOTRICHON PRATENSE IN WESTERN AND CENTRAL LATVIA

    Directory of Open Access Journals (Sweden)

    S. RUSINA

    2003-06-01

    Full Text Available The dry calcareous grassland vegetation of Westem and Central Latvia is described based on 93 rclevés, Ali relevés could be assigned to one community type Filipendula vulgaris-Helictotrichon pratense named according to dominant species. Four variants were distinguished: typicum, Viscaria vulgaris, Astragalus danicus and Carex flacca. Ellenberg indìcator values were calculated to study the ecology of communities. Floristic differences among variants are associated mainly with soil reaction (Ellenberg indicator values for soil pH range from 6.0 to 7.6, but conditions of moisture and fertility are similar among the variants. The calcareous grassland vegetation in Latvia represents transition vegetation between the c1asses Molinio-Arrhenatheretea and Festuco-Brometea. However, ecologically and floristically, these communities are closer to the class Festuco-Brometea and could be assigned to the order Brometalia. For designation to alliance and associations, more data is required. The results are compared with similar communities in other European countries.

  7. Pleistocene calcareous nannofossil biochronology at IODP Site U1385 (Expedition 339)

    Science.gov (United States)

    Balestra, B.; Flores, J.-A.; Hodell, D. A.; Hernández-Molina, F. J.; Stow, D. A. V.

    2015-12-01

    During Integrated Ocean Drilling Program (IODP) Expedition 339, Site U1385 (37°34‧N, 10°7‧W, 2578 m below sea level) was drilled in the lower slope of the Portuguese margin, to provide a marine reference section of Pleistocene millennial-scale climate variability. Five holes were cored using the Advanced Piston Corer (APC) to a depth of ~ 151 m below sea floor (mbsf) recovering a continuous stratigraphic record covering the past 1.4 Ma. Here we present results of the succession of standard and unconventional calcareous nannofossil biostratigraphic events. The quantitative study of calcareous nannofossils showed well-preserved and abundant assemblages throughout the core. Most conventional Pleistocene events were recognized and the timing of bioevents were calibrated using correlation to the new oxygen isotope stratigraphy record developed for the Site U1385. The analyses provide further data on the stratigraphic distribution of selected species and genera, such as the large Emiliania huxleyi (> 4 μm), Gephyrocapsa caribbeanica, Helicosphaera inversa, Gephyrocapsa omega and Reticulofenestra asanoi (> 6 μm) and other circular-subcircular small reticulofenestrids, resulting in new insights into the environmental control of their stratigraphic patterns. Finally, the comparison between nannofossil datums and oxygen isotope stratigraphy on the same samples has resulted in an accurate revision of timing of the events, providing valuable biochronologic information.

  8. Characterization of commercial iron chelates and their behavior in an alkaline and calcareous soil.

    Science.gov (United States)

    Cantera, Rodrigo G; Zamarreño, Angel M; García-Mina, José M

    2002-12-18

    Iron deficiency is a common problem for many plants grown in alkaline and calcareous soils. To correct this problem, iron is supplied to plants as chelates. Several iron chelates are sold under diverse trademarks with different characteristics. This work evaluated 18 commercial products containing the most representative chelated iron sources used in agricultural practice in Spain when the study was done, namely the ferric chelates of EDDHA, EDDHMA, EDDCHA, EDDHSA, EDTA, and DTPA. The chelates were comprehensively characterized and quantitated by several techniques, including several chromatographic methods. Iron and chelate dynamics in soil were also studied in a model alkaline and calcareous soil. Results indicate that, in this model soil, among the different iron compounds studied only FeEDDHA and analogues have the capacity to maintain soluble iron in soil solution over time. These results are in agreement with general experience under field conditions. Furthermore, among the different ortho-ortho isomers of FeEDDHA's, FeEDDHSA and FeEDDCHA showed greater capacity than FeEDDHA and FeEDDHMA to maintain the chelated iron in soil solution over time.

  9. LEAF MINERAL CONCENTRATION OF FIVE OLIVE CULTIVARS GROWN ON CALCAREOUS SOIL

    Directory of Open Access Journals (Sweden)

    Igor Pasković

    2013-12-01

    Full Text Available There are limited numbers of scientific publication regarding genotypic differences which exist among olive cultivars concerning nutrient uptake and translocation. For that purpose, the object of our study was to determine possible differences between leaf mineral content of five selected olive cultivars since leaf nutrient analysis is consider being the best method for diagnosing olive tree nutritional status. Plant material was obtained from an olive collection, grown on calcareous soil maintained at Institute of Adriatic Crops and Karst Reclamation, Split, Croatia. The study was conducted with two Croatian autochthonous olive cultivars (“Istarska bjelica”, “Lastovka”, two Italian cultivars (“Pendolino”, “Leccino” and one Spanish cultivar (“Hojiblanca”. Completely randomized design was applied. This study has shown questionably low Mg concentration in all olive cultivars with exception for “Hojiblanca” cultivar. Also, only Croatian cultivars “Istarska bjelica” and “Lastovka” as well as Spanish cultivar “Hojiblanca” recorded sufficient levels of iron leaf mineral content. Regarding other elements studied (P, K, Ca, Zn, Mn, Cu all cultivars were above literature cited thresholds for possible deficiencies. Selected olive cultivars in our experiment demonstrated different nutrient leaf concentration, which is of particular importance for fertilization requirements and fertilization practice in Croatian orchards grown on calcareous soil.

  10. Histochemical and ultrastructural studies on the calcareous corpuscles and eggs of Taenia taeniaeformis and Dipylidium caninum.

    Science.gov (United States)

    Khalifa, Refaat M A; Mazen, Nawal A M; Marawan, Aziza M A; Thabit, Hasnaa T M

    2011-08-01

    Calcareous corpuscles were noticed by several previous workers to be present in larval and adult cestodes without knowing their function. However, nothing was mentioned in the available literature about distribution of these corpuscles and their density, structure and composition in different parts of the body of different cestodes. Hence, in the present work, a comparative study of their distribution, density, histochemical and ultrastructural characters in different parts of the body was performed in Taenia taeniaeformis and Dipylidium caninum. Due to the presence of the eggs in their gravid segments, their histochemical and ultrastructural characteristics were also studied. It was found that the size, location and density of the calcareous bodies were different in different body parts of the same and the other cestode. Histochemically, the main component of these corpuscles was calcium; while other constituents as polysaccharides, lipids, protrins and mucopolysaccharides were found in their outer rim. Ultrastructurally, they were quite similar in the two studied cestodes and different stages of their development were exhibited. Histochemically, the eggs of both cestodes were similar in their contents. However, some ultrastructural differences have been demonstrated particularly in relation to the size and shape of the rods in the embryophore and the structures in between the embryophore and onchosphere.

  11. Adsorption and co-adsorption of diclofenac and Cu(II) on calcareous soils.

    Science.gov (United States)

    Graouer-Bacart, Mareen; Sayen, Stéphanie; Guillon, Emmanuel

    2016-02-01

    Pharmaceuticals are emerging contaminants and their presence in different compartments of the environment has been detected in many countries. In this study, laboratory batch experiments were conducted to characterize the adsorption of diclofenac, a widely used non-steroidal anti-inflammatory drug, on six calcareous soils. The adsorption of diclofenac was relatively low, which may lead to a risk of groundwater contamination and plant uptake. A correlation between the soil-water distribution coefficient Kd and soil characteristics has been highlighted. Indeed, diclofenac adsorption as a function of soil organic matter content (% OM) and Rt=% CaCO3/% OM was successfully described through a simple empirical model, indicating the importance of considering the inhibiting effect of CaCO3 on OM retention properties for a better assessment of diclofenac fate in the specific case of calcareous soils. The simultaneous co-adsorption of diclofenac and copper - a ubiquitous pollutant in the environment - at the water/soil interface, was also investigated. It appeared quite unexpectedly that copper did not have a significant influence on diclofenac retention. Copyright © 2015 Elsevier Inc. All rights reserved.

  12. Sinemurian–Pliensbachian calcareous nannofossil biostratigraphy and organic carbon isotope stratigraphy in the Paris Basin

    DEFF Research Database (Denmark)

    Peti, Leonie; Thibault, Nicolas Rudolph; Clemence, Marie-Emilie

    2017-01-01

    The biostratigraphy of Sinemurian to lower Toarcian calcareous nannofossils has been investigated in the Sancerre-Couy core (Paris Basin), which contains a mixed assemblage of species with affinities to the northern and southern areas of the peri-tethyan realm, thus allowing for the use and calib......The biostratigraphy of Sinemurian to lower Toarcian calcareous nannofossils has been investigated in the Sancerre-Couy core (Paris Basin), which contains a mixed assemblage of species with affinities to the northern and southern areas of the peri-tethyan realm, thus allowing for the use...... organic carbon isotope curve based on 385 data points. The main bioevents, i.e. the first occurrences of Parhabdolithus liasicus, Crepidolithus pliensbachensis, Crepidolithus crassus, Mitrolithus lenticularis, Similiscutum cruciulus sensu lato, Lotharingius hauffii, Crepidolithus cavus and Lotharingius...... between the different domains. In addition to the nine main bioevents used for the biozonation of the core, we document an additional 50 distinct bioevents, evaluate their reliability and discuss their potential significance by comparison to previous studies. A total of five significant negative organic...

  13. The siliceous-calcareous-argillaceous rock type uranium deposit in south subzone of Western Qinling

    International Nuclear Information System (INIS)

    Qian Farong; Zhou Dean; Ji Hongfang

    1995-11-01

    The siliceous-calcareous-argillaceous rock type uranium deposit in south subzone of western Qinling is an inland found type deposit with specific mineralization and good potentiality. The mineralization distributes along definite horizons and occurs in siliceous layer and lenses of siliceous-calcareous rocks. Orebody presents in forms of stratoid, lenticular and irregular veins and controlled by factorial structures. Ore is identified as massive and sandy and each characterized by various mineral compositions and element associations. The study shows that the mineralizing materials are mainly derived from ore-bearing strata. The metallogenic environment has characteristics of middle-low temperature and supergene The metallogenesis underwent three stages: (1) Sedimentation-diagenesis of the ore-bearing strata led to preliminary concentration of uranium; (2) Polytectonic activities accompanied by underground hydrothermal process resulted in the industrial concentration of uranium; and (3) Orebody reworked by oxidation-denudation and leaching, locally has taken place secondary concentration. The deposit in origin attributes to polygenesis dominated by underground hydrothermal metallogenesis. Main metallogenic epoch happens during the periods of Late Yanshan and Himalayan. According to the geological-tectonic conditions the further prospecting direction in study area is proposed. (3 refs., 5 figs., 9 tabs.)

  14. Physiological Responses of Some Iranian Grape Cultivars to Iron Chelate Application in Calcareous Soil

    Directory of Open Access Journals (Sweden)

    H. Doulati Baneh

    2016-07-01

    Full Text Available Introduction: Iron chlorosis is considered to be one of the most important nutritional disorders in grapevines, particularly in calcareous soils that under these conditions fruit yield and quality is depressed in the current year and fruit buds poorly develop for following year. Symptoms of iron chlorosis in orchards and vineyards are usually more frequent in spring when shoot growth is rapid and bicarbonate concentration in the soil solution buffers soil pH in the rhizosphere and root apoplast. Several native grapevine (Vitis vinifera L. genotypes, highly appreciated for their organoleptic characteristics and commercial potential, are widely cultivated in Iran. Cultivated plants differ as to their susceptibility to Fe deficiency in calcareous soils, some being poorly affected while others showing severe leaf chlorotic symptoms. Selection and the use of Fe-efficient genotypes is one of the important approaches to prevent this nutritional problem. In this research the response of three local grapevine cultivars was evaluated to iron chelate consumption in a calcareous soil (26% T.N.V. Materials and Methods: Well rooted woody cuttings of three autochthonous varieties (Rasha, Qezel uzum, Keshmeshi Qermez were cultivated in pots filled with a calcareous soil with iron chelate consumption at three rates (0, 7.5 and 15 mg Fe/ Kg soil. The study was conducted with two factors (cultivar and iron chelate and 3 replicates in a factorial arrangement based on randomized complete block design. Plant parameters including vegetative growth, chlorophyll index and leaf area were monitored during the growth period. At the end of the treatment, fresh and dry weight of shoots and roots were determined. The concentrations of macro and micro elements in the leaves were assayed using an atomic absorption and spectrophotometer. One-way-ANOVA was applied comparing the behavior of the cultivars growing. Results and Discussion: Analysis of variance showed that chlorophyll

  15. Ozone pollution affects flower numbers and timing in a simulated BAP priority calcareous grassland community

    International Nuclear Information System (INIS)

    Hayes, Felicity; Williamson, Jennifer; Mills, Gina

    2012-01-01

    Mesocosms representing the BAP Priority habitat ‘Calcareous Grassland’ were exposed to eight ozone profiles for twelve-weeks in two consecutive years. Half of the mesocosms received a reduced watering regime during the exposure periods. Numbers and timing of flowering in the second exposure period were related to ozone concentration and phytotoxic ozone dose (accumulated stomatal flux). For Lotus corniculatus, ozone accelerated the timing of the maximum number of flowers. An increase in mean ozone concentration from 30 ppb to 70 ppb corresponded with an advance in the timing of maximum flowering by six days. A significant reduction in flower numbers with increasing ozone was found for Campanula rotundifolia and Scabiosa columbaria and the relationship with ozone was stronger for those that were well-watered than for those with reduced watering. These changes in flowering timing and numbers could have large ecological impacts, affecting plant pollination and the food supply of nectar feeding insects. - Highlights: ► An increase in ozone accelerated timing of maximum flowering in Lotus corniculatus. ► Ozone reduced flower numbers in Campanula rotundifolia and Scabiosa columbaria. ► Reduced water availability did not protect most species from the effects of ozone. - Increased tropospheric ozone affected timing of flowering and maximum flower numbers in calcareous grassland mesocosms.

  16. Phosphorus reduces the zinc concentration in cereals pot-grown on calcareous Vertisols from southern Spain.

    Science.gov (United States)

    Sánchez-Rodríguez, Antonio Rafael; Del Campillo, María Carmen; Torrent, José

    2017-08-01

    Zinc deficiency, a major problem in crops grown on soils low in available Zn, is even more important in phosphorus-rich soils. This work aimed to elucidate the effects of soil P and Zn levels, and of fertilizer application, on yield and Zn concentration in cereal grains. Wheat and barley were successively pot-grown on 20 calcareous Vertisols low in available Zn and ranging widely in available P. Grain yield in the plants grown on the native soils was positively correlated with Olsen P but not with diethylenetriaminepentaacetic acid (DTPA)-extractable Zn except for wheat on P-rich soils. Grain Zn concentration was negatively correlated with Olsen P. Grain Zn uptake differed little among soils. Application of P to the soils increased grain yield insignificantly and P concentration significantly; however, it reduced grain Zn concentration (particularly at low Olsen P values). Applying Zn alone only increased grain Zn concentration, whereas applying P and Zn in combination increased yield and grain Zn concentration at low and high Olsen P values, respectively. Applying P alone to plants grown on calcareous Vertisols low in available P and Zn may in practice reduce grain Zn concentrations while not increasing grain yield significantly. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  17. Dried gamma-irradiated sewage solids use on calcareous soils: crop yeilds and heavy metals uptake

    Energy Technology Data Exchange (ETDEWEB)

    McCaslin, B.D.; Sivinski, J.S.

    1979-01-01

    Experiments designed to examine gamma-radiation effects on extractable and plant-available sludge elements and to examine the response of crops to sludge applications on two typical, calcareous soils in New Mexico are summarized. Information has been given indicating that the radiation process of reducing pathogens in sewage products being developed by Sandia Laboratories, does not significantly increase the chemical extractability and plant uptake of a broad range of nutrients and heavy metals. However, radiation treatment greatly facilitates handling sewage for experimentation, because pathogen contamination precautions are eliminated and weed seeds killed. Studies on the effects of sludge irradiation on plant nutrient uptake revealed no concentration increases, agreeing with results presented herein. Sewage products may have special potential for use on calcareous soils, such as in New Mexico. For instance, in New Mexico the lack of potassium in sewage products is not a problem and the naturally high pH of New Mexico soil greatly reduces plant availability of many problem heavy metals. Dramatic increases in yield are typified by the greenhouse and field results presented herein, especially for the known micronutrient deficient soils of New Mexico. Results indicate that sewage sludge is an excellent Zn and Fe fertilizer. More research needs to be done before the economics of sludge application can be calculated and more field information is needed before irradiated sewage products are used indiscriminately. (ERB)

  18. Miocene oceanographic changes of the western equatorial Atlantic (Ceara Rise) based on calcareous dinoflagellate cysts

    Science.gov (United States)

    Heinrich, S.; Zonneveld, K. A. F.; Willems, H.

    2010-09-01

    The middle- and upper Miocene represent a time-interval of major changes in palaeoceanography that favoured the cooling of the climate and culminated in the Northern Hemisphere Glaciation (NHG). The basis for the development of the modern deepwater circulation pattern, e.g. thermohaline circulation, was hereby established. Tectonic events played a key role in the progressing Miocene oceanography, such as the narrowing of the Panama gateway (e.g. Duque-Caro 1990) and the possible linked changes in North Atlantic Deep Water formation (Lear et al. 2003). However, the complex interaction between the closing of the Panama Gateway, the development of NADW, and thus the oceanographic progression towards our present day circulation is far from being fully understood. We want to improve the understanding of these processes by establishing a detailed palaeoceanographic reconstruction of the western equatorial Atlantic Ocean on the basis of calcareous dinoflagellate cyst (dinocyst) associations. Within this study, we investigated sediment samples from ODP Site 926A by defining the calcareous dinocyst assemblage. Site 926A is located at the southwestern flank of the Ceara Rise, an area of highest sensitivity to global deep water circulation changes. At about 12 Ma, when NADW production increased (e.g. Wright et al. 1992), we see a distinct increase in the absolute abundances of the calcareous dinocysts. This might be related to enhanced productivity or to better carbonate preservation. At 11.3 Ma, Leonella granifera, a species known to be strongly related to terrestrial input occurs. This could be a signal for the initiation of the Amazon River as a transcontinental river with the development of the Amazon fan (11.8 - 11.3 Ma; Figueiredo et al. 2009) in relation to Andean tectonism. References: Duque-Caro, H. (1990): Neogene stratigraphy, paleoceanography and palebiology in Northwest South America and the evolution of the Panama Seaway. Palaeogeography, Palaeoclimatology

  19. Biochar and manure affect calcareous soil and corn silage nutrient concentrations and uptake.

    Science.gov (United States)

    Lentz, R D; Ippolito, J A

    2012-01-01

    Carbon-rich biochar derived from the pyrolysis of biomass can sequester atmospheric CO, mitigate climate change, and potentially increase crop productivity. However, research is needed to confirm the suitability and sustainability of biochar application to different soils. To an irrigated calcareous soil, we applied stockpiled dairy manure (42 Mg ha dry wt) and hardwood-derived biochar (22.4 Mg ha), singly and in combination with manure, along with a control, yielding four treatments. Nitrogen fertilizer was applied when needed (based on preseason soil test N and crop requirements) in all plots and years, with N mineralized from added manure included in this determination. Available soil nutrients (NH-N; NO-N; Olsen P; and diethylenetriaminepentaacetic acid-extractable K, Mg, Na, Cu, Mn, Zn, and Fe), total C (TC), total N (TN), total organic C (TOC), and pH were evaluated annually, and silage corn nutrient concentration, yield, and uptake were measured over two growing seasons. Biochar treatment resulted in a 1.5-fold increase in available soil Mn and a 1.4-fold increase in TC and TOC, whereas manure produced a 1.2- to 1.7-fold increase in available nutrients (except Fe), compared with controls. In 2009 biochar increased corn silage B concentration but produced no yield increase; in 2010 biochar decreased corn silage TN (33%), S (7%) concentrations, and yield (36%) relative to controls. Manure produced a 1.3-fold increase in corn silage Cu, Mn, S, Mg, K, and TN concentrations and yield compared with the control in 2010. The combined biochar-manure effects were not synergistic except in the case of available soil Mn. In these calcareous soils, biochar did not alter pH or availability of P and cations, as is typically observed for acidic soils. If the second year results are representative, they suggest that biochar applications to calcareous soils may lead to reduced N availability, requiring additional soil N inputs to maintain yield targets. Copyright © by the

  20. Fate of Zinc Oxide Nanoparticles Coated onto Macronutrient Fertilizers in an Alkaline Calcareous Soil

    Science.gov (United States)

    Milani, Narges; Hettiarachchi, Ganga M.; Kirby, Jason K.; Beak, Douglas G.; Stacey, Samuel P.; McLaughlin, Mike J.

    2015-01-01

    Zinc oxide (ZnO) nanoparticles may provide a more soluble and plant available source of Zn in Zn fertilizers due to their greater reactivity compared to equivalent micron- or millimetre-sized (bulk) particles. However, the effect of soil on solubility, spatial distribution and speciation of ZnO nanoparticles has not yet been investigated. In this study, we examined the diffusion and solid phase speciation of Zn in an alkaline calcareous soil following application of nanoparticulate and bulk ZnO coated fertilizer products (monoammonium phosphate (MAP) and urea) using laboratory-based x-ray techniques and synchrotron-based μ-x-ray fluorescence (μ–XRF) mapping and absorption fine structure spectroscopy (μ–XAFS). Mapping of the soil-fertilizer reaction zones revealed that most of the applied Zn for all treatments remained on the coated fertilizer granule or close to the point of application after five weeks of incubation in soil. Zinc precipitated mainly as scholzite (CaZn2(PO4)2.2H2O) and zinc ammonium phosphate (Zn(NH4)PO4) species at the surface of MAP granules. These reactions reduced dissolution and diffusion of Zn from the MAP granules. Although Zn remained as zincite (ZnO) at the surface of urea granules, limited diffusion of Zn from ZnO-coated urea granules was also observed for both bulk and nanoparticulate ZnO treatments. This might be due to either the high pH of urea granules, which reduced solubility of Zn, or aggregation (due to high ionic strength) of released ZnO nanoparticles around the granule/point of application. The relative proportion of Zn(OH)2 and ZnCO3 species increased for all Zn treatments with increasing distance from coated MAP and urea granules in the calcareous soil. When coated on macronutrient fertilizers, Zn from ZnO nanoparticles (without surface modifiers) was not more mobile or diffusible compared to bulk forms of ZnO. The results also suggest that risk associated with the presence of ZnO NPs in calcareous soils would be the

  1. Influence of Blended Cements with Calcareous Fly Ash on Chloride Ion Migration and Carbonation Resistance of Concrete for Durable Structures.

    Science.gov (United States)

    Glinicki, Michał A; Jóźwiak-Niedźwiedzka, Daria; Gibas, Karolina; Dąbrowski, Mariusz

    2016-01-02

    The objective of this paper is to examine the possible use of new blended cements containing calcareous fly ash in structural concrete, potentially adequate for structural elements of nuclear power plants. The investigation included five new cements made with different contents of non-clinker constituents: calcareous fly ash, siliceous fly ash, ground granulated blastfurnace slag, and a reference cement-ordinary Portland cement. The influence of innovative cements on the resistance of concrete to chloride and carbonation exposure was studied. Additionally, an evaluation of the microstructure was performed using optical microscopy on concrete thin sections. Test results revealed a substantial improvement of the resistance to chloride ion penetration into concrete containing blended cements. The resistance was higher for increased clinker replacement levels and increased with curing time. However, concrete made with blended cements exhibited higher depth of carbonation than the Portland cement concrete, except the Portland-fly ash cement with 14.3% of calcareous fly ash. The thin sections analysis confirmed the values of the carbonation depth obtained from the phenolphthalein test. Test results indicate the possible range of application for new cements containing calcareous fly ash.

  2. Influence of Blended Cements with Calcareous Fly Ash on Chloride Ion Migration and Carbonation Resistance of Concrete for Durable Structures

    Directory of Open Access Journals (Sweden)

    Michał A. Glinicki

    2016-01-01

    Full Text Available The objective of this paper is to examine the possible use of new blended cements containing calcareous fly ash in structural concrete, potentially adequate for structural elements of nuclear power plants. The investigation included five new cements made with different contents of non-clinker constituents: calcareous fly ash, siliceous fly ash, ground granulated blastfurnace slag, and a reference cement—ordinary Portland cement. The influence of innovative cements on the resistance of concrete to chloride and carbonation exposure was studied. Additionally, an evaluation of the microstructure was performed using optical microscopy on concrete thin sections. Test results revealed a substantial improvement of the resistance to chloride ion penetration into concrete containing blended cements. The resistance was higher for increased clinker replacement levels and increased with curing time. However, concrete made with blended cements exhibited higher depth of carbonation than the Portland cement concrete, except the Portland-fly ash cement with 14.3% of calcareous fly ash. The thin sections analysis confirmed the values of the carbonation depth obtained from the phenolphthalein test. Test results indicate the possible range of application for new cements containing calcareous fly ash.

  3. Zanclean/Piacenzian transition on Cyprus (SE Mediterranean): calcareous nannofossil and Sea Surface Temperatures evidence of sapropel formation

    Science.gov (United States)

    Athanasiou, Maria; Triantaphyllou, Maria; Bouloubassi, Ioanna; Dimiza, Margarita; Gogou, Alexandra; Klein, Vincent; Parinos, Constantine; Theodoroyu, George

    2016-04-01

    Quantitative analyses of calcareous nannofossils in the sediments of Pissouri South section on the island of Cyprus have produced a paleoceanographic record reflecting the paleoclimatic conditions during Zanclean/Piacenzian transition. According to the performed calcareous nannofossil biostratigraphy the studied section is correlated with MNN14/15 and MNN16 calcareous nannofossil biozones and is astronomically dated between 4.065 and 3.217 Ma. Intervals of increased organic carbon content along with the positive values of Florisphaera profunda, Helicosphaera sellii, Discoaster spp. and the subsequent increase of stratification S-index correspond to the sapropel deposition during periods of wetter climate and intense continental runoff especially from the river Nile. These layers are alternating with grey marly intervals, featured by the increased values of small placoliths of Reticulofenestra and Gephyrocapsa species, which are indicative of eutrophic conditions during intense surface waters mixing. Pissouri South section comprises a SSTs sequence using alkenone unsaturation index (Uk 37) providing with the first continuous record from SE Mediterranean covering the Zanclean/Piacenzian (Pliocene) transition (~ 4.1-3.2 Ma). Correlation of the total alkenone concentration to the calcareous nannofossil assemblage and especially representatives among Noelaerhabdaceae family revealed that Pseudoemiliania lacunosa probably had similar temperature sensitivity to that of Emiliania huxleyi, currently producing alkenones in present day oceans.Our data support the prevalence of a generally warm phase characterized by the absence of high-frequency climate variations in the southeastern Mediterranean during the Zanclean/Piacenzian (Early/Late Pliocene) transition.

  4. Nitrogen deposition and grass encroachment in calcareous and acidic Grey dunes (H2130) in NW-Europe

    NARCIS (Netherlands)

    Kooijman, A.M.; van Til, M.; Noordijk, E.; Remke, E.; Kalbitz, K.

    We present an overview of high nitrogen deposition effects on coastal dune grasslands in NW-Europe (H2130), especially concerning grass encroachment in calcareous and acidic Grey Dunes. The problem is larger than previously assumed, because critical loads are still too high, and extra N-input from

  5. Impacts of long-term nitrogen fertilization on acid buffering rates and mechanisms of a slightly calcareous clay soil

    NARCIS (Netherlands)

    Zhang, Yuting; Vries, de Wim; Thomas, Ben W.; Hao, Xiying; Shi, Xiaojun

    2017-01-01

    Acidification of cropland soils is a serious problem in China that may cause long term pH decline, which threatens the sustainability of soil fertility and crop yields. The objective of this research was to investigate those rates and mechanisms for a slightly calcareous soil. The field data were

  6. Iron biofortification of wheat grains through integrated use of organic and chemical fertilizers in pH affected calcareous soil.

    Science.gov (United States)

    Ramzani, Pia Muhammad Adnan; Khalid, Muhammad; Naveed, Muhammad; Ahmad, Rashid; Shahid, Muhammad

    2016-07-01

    Incidence of iron (Fe) deficiency in human populations is an emerging global challenge. This study was conducted to evaluate the potential of iron sulphate combined with biochar and poultry manure for Fe biofortification of wheat grains in pH affected calcareous soil. In first two incubation studies, rates of sulfur (S) and Fe combined with various organic amendments for lowering pH and Fe availability in calcareous soil were optimized. In pot experiment, best rate of Fe along with biochar (BC) and poultry manure (PM) was evaluated for Fe biofortification of wheat in normal and S treated low pH calcareous soil. Fe applied with BC provided fair increase in root-shoot biomass and photosynthesis up to 79, 53 and 67%, respectively in S treated low pH soil than control. Grain Fe and ferritin concentration was increased up to 1.4 and 1.2 fold, respectively while phytate and polyphenol was decreased 35 and 44%, respectively than control in treatment where Fe was applied with BC and S. In conclusion, combined use of Fe and BC could be an effective approach to improve growth and grain Fe biofortification of wheat in pH affected calcareous soil. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  7. Ocean Acidification: Investigation and Presentation of the Effects of Elevated Carbon Dioxide Levels on Seawater Chemistry and Calcareous Organisms

    Science.gov (United States)

    Buth, Jeffrey M.

    2016-01-01

    Ocean acidification refers to the process by which seawater absorbs carbon dioxide from the atmosphere, producing aqueous carbonic acid. Acidic conditions increase the solubility of calcium carbonate, threatening corals and other calcareous organisms that depend on it for protective structures. The global nature of ocean acidification and the…

  8. SPRINGS WITH CALCAREOUS TUFA IN THE VALLEY OF THE JAMNE CREEK IN GORCE

    Directory of Open Access Journals (Sweden)

    Roksana Krause

    2015-01-01

    Full Text Available The study gives a detail characteristic of a hard water springs habitat with the communities of Cratoneurion commutati (habitat code of Nature 2000: 7220, localized within Nature 2000 protected area Ostoja Gorczańska PLH120018, in an upper part of the valley of Jamne creek. The plants are described along with the main habitat parameters, namely: altitude, exposition, slope gradient, insolation, type of bedrock, water flow regime and the spring outflow efficiency. The temperature, pH, electrical conductivity were measured in the field, the concentrations of Ca and Mg in spring water were measured by Atomic Absorption Spectroscopy (AAS. The investigated headwater areas are small (0.7–80 m2 and highly differentiated by the intensity of calcareous tufa precipitation and the degree of plant cover development.

  9. Validation of water sorption-based clay prediction models for calcareous soils

    DEFF Research Database (Denmark)

    Arthur, Emmanuel; Razzaghi, Fatemeh; Moosavi, Ali

    2017-01-01

    on prediction accuracy. The soils had clay content ranging from 9 to 61% and CaCO3 from 24 to 97%. The three water sorption models considered showed a reasonably fair prediction of the clay content from water sorption at 28% relative humidity (RMSE and ME values ranging from 10.6 to 12.1 and −8.1 to −4......Soil particle size distribution (PSD), particularly the active clay fraction, mediates soil engineering, agronomic and environmental functions. The tedious and costly nature of traditional methods of determining PSD prompted the development of water sorption-based models for determining the clay...... fraction. The applicability of such models to semi-arid soils with significant amounts of calcium carbonate and/or gypsum is unknown. The objective of this study was to validate three water sorption-based clay prediction models for 30 calcareous soils from Iran and identify the effect of CaCO3...

  10. Transformation of nitrogenous fertilizers of surface and deep application in calcareous soil

    International Nuclear Information System (INIS)

    Zuo Dongfeng

    1990-01-01

    The transformations of 15 N labelled fertilizer N in calcareous soil were studied under greennhouse conditions. The experimental results indicate that the ratio of fixed ammonium is closely related to the methods of fertilizer application to the soil. When fertilizer N applied as deep dressing the fixation of nitrogen by clay minerals and microorganisms may markedly reduce the losses of nitrogen, but the amount of nitrogen fixed by the clay minerals and that by microorganisms showed negative correlation (r = -0.9185 ** ). The more the amount of fixed nitrogen by clay minerals, the less by microorganisms. No obvious interrelation between the residual utilization of urea, ammonium bicarbonate, ammonium sulfate and the ammount of nitrogen fixed by organisms can be observed, but the residual utilization of these fertilizers by the succeeding crop has been related to the total amount of mineral nitrogen

  11. Soil seed-bank composition reveals the land-use history of calcareous grasslands

    Science.gov (United States)

    Karlík, Petr; Poschlod, Peter

    2014-07-01

    We compared soil seed banks and vegetation of recent (established on abandoned arable fields) and ancient (continuously managed as pastures at least since 1830) calcareous grasslands if there is any impact of former arable field use. The study was carried out in two regions of Southern Germany with well-preserved dry grassland vegetation: the western Jurassic mountains (Kaltes Feld) and the climatically drier eastern part of Southern Germany (Kallmünz). Total number of species in the seed bank was similar in both regions, but species composition partly differed, reflecting phytogeographical differences between the regions. The total number of emerged seedlings showed a large disparity (5457 compared to 2523 seedlings/m2 in Kaltes Feld and Kallmünz, respectively). Though there were differences in seed bank composition and size, we found a uniform pattern of plant traits (affiliation to phytosociological groups, Raunkiaer plant life-forms and seed longevity), which depended on the age of the grassland. The main conclusion is that seed banks in contemporary calcareous grasslands still reflect the history of former land use - in this case arable cultivation, even though it occurred a long time ago (up to 150 years). Indicators of former arable fields are germinable seeds of weeds which have persisted in the soil to the present. By contrast, weedy species are completely absent from the seed banks of ancient grasslands. Soil seed banks of recent grasslands may be of substantial conservation importance because they may store seeds of rare and endangered weed species such as Kickxia spuria, Silene noctiflora and Stachys annua, the majority of which have already gone extinct from the current vegetation of the study sites.

  12. Effect of phosphate fertilization on the bioavailability of iron in calcareous soils

    Science.gov (United States)

    Sánchez-Rodríguez, A. R.; del Campillo, M. C.; Barrón, V.; Torrent, J.

    2012-04-01

    Iron (Fe) chlorosis is the most important nutritional problem in sensitive plant species cultivated in calcareous soils, its main symptoms being interveinal yellowing in the younger leaves due to lack of chlorophyll and reduced growth. Fe chlorosis has been related to the content of poorly crystalline Fe oxides in soil. The effect of other nutrients, especially phosphorus (P), is, however, a matter of debate. In this work we examined whether fertilization with P alters the availability of Fe to sensitive plants growing in two different Fe chlorosis-inducing calcareous soils. Phosphate at rates of 0 (control), 25, 50, 100 and 200 mg P kg-1 soil was applied to pots where six-months-old olive trees cv. Arbequina were grown. The experiment lasted three years and took place in a shaded house. Chlorophyll concentration in the young leaves was estimated with the SPAD value (using a Minolta apparatus) three-four times per year. Furthermore, shoot length, dry weight of annual pruning and mineral element concentration were measured at the end of each year. In one of the soils, SPAD and leaf Fe concentration decreased with increasing P dose. However in the other soil, SPAD was not correlated with the rate of applied P. In both soils, potassium and zinc concentrations in plants fertilized with P were lower than those in the control plants. This work was funded by the Spanish Ministry of Science and Innovation, Projects: AGL 2005-06691-C02-01 and AGL 2008-05053-C02-02, and the European Regional Development Funds. ARSR acknowledges the finnancial support from the Spanish Ministry of Education as a fellow of the program "Training of University Teachers" (Formación del Profesorado Universitario, AP2008-04716)

  13. Enhancing the Durability of Calcareous Stone Monuments of Ancient Egypt Using CaCO3 Nanoparticles

    Directory of Open Access Journals (Sweden)

    Mohammad A. Aldoasri

    2017-08-01

    Full Text Available The unwanted changes in valuable historic calcareous stone monuments due to exposure to many physical and chemical effects may lead to its deterioration. The growing interest in the field of conservation of stone monuments encourages the development of consolidation and water-repellent materials. The aim of this study is to evaluate the effectiveness of CaCO3 nanoparticles as a consolidation and protection material for calcareous stone monuments, when those nanoparticles used are dispersed in acrylic copolymer; polyethylmethacrylate (EMA/methylacrylate (MA (70/30, respectively. Samples were subjected to artificial aging by relative humidity/temperature to show the optimum conditions of durability and the effectiveness of the nano-mixture in improving the physical and mechanical properties of the stone material. The synthesis process of CaCO3 nanoparticles/polymer nanocomposite has been prepared by in situ emulsion polymerization system. The prepared nanocomposites with 0.15 g CaCO3 nanoparticles showed obvious transparency features and represent nanocomposites coating technology with hydrophobic, consolidating and good protection properties. Some tests were performed in order to estimate the superficial consolidating and protective effect of the treatment. The obtained nanocomposites have been characterized by TEM, while the surface morphology before and after treatment and homogeneous distribution of used consolidation materials on stone surface were examined by SEM. Improvement of stone mechanical properties was evaluated by compressive strength tests. Change in water-interaction properties was evaluated by water absorption capillarity measurements, and colorimetric measurements were used to evaluate the optical appearance. Taken together, the results indicate that CaCO3/polymer nanocomposite is a completely compatible, efficient material for the consolidation of artistic and architectural limestone monuments capable of enhancing the

  14. Adsorption of enrofloxacin in presence of Zn(II) on a calcareous soil.

    Science.gov (United States)

    Graouer-Bacart, Mareen; Sayen, Stéphanie; Guillon, Emmanuel

    2015-12-01

    As a result of their consumption, excretion, disposal and persistence, antibiotics enter the soil environment and may be transported to surface and ground waters. During their transfer through soils, retention processes play a key role in their mobility. Antibiotics often coexist with heavy metals in soils due to agricultural practices and other sources of inputs. In this context, this study deals with the co-adsorption of Zn(II) and enrofloxacin (ENR), a widely-used veterinary antibiotic, on a calcareous soil using batch retention experiments and X-ray Absorption Near Edge Structure (XANES) spectroscopy. To improve our understanding of the interaction of this emerging organic contaminant with metal cations at the water-soil interface, the ternary system containing ENR, Zn(II) and a selected calcareous soil was investigated over a pH range between 7 and 10, at different solid-solution contact times and ENR concentrations. The presence of Zn(II) slightly influenced the retention of the antibiotic, leading to an increase of the adsorbed ENR amounts. The distribution coefficient Kd value increased from 0.66 Lg(-1) for single ENR adsorption to 1.04 Lg(-1) in presence of Zn(II) at a 1/2 ENR/Zn(II) ratio. The combination of adsorption isotherm data, solution speciation diagrams and XANES spectra evidenced a small proportion of Zn(II)-ENR complexes at soil pH leading to the slight increase of ENR adsorption in presence of zinc. These results suggest that it is necessary to consider the interaction between ENR and metal cations when assessing the mobility of ENR in soils. Copyright © 2015 Elsevier Inc. All rights reserved.

  15. Spatial and seasonal reef calcification in corals and calcareous crusts in the central Red Sea

    KAUST Repository

    Roik, Anna Krystyna; Roder, Cornelia; Rö thig, Till; Voolstra, Christian R.

    2015-01-01

    The existence of coral reef ecosystems critically relies on the reef carbonate framework produced by scleractinian corals and calcareous crusts (i.e., crustose coralline algae). While the Red Sea harbors one of the longest connected reef systems in the world, detailed calcification data are only available from the northernmost part. To fill this knowledge gap, we measured in situ calcification rates of primary and secondary reef builders in the central Red Sea. We collected data on the major habitat-forming coral genera Porites, Acropora, and Pocillopora and also on calcareous crusts (CC) in a spatio-seasonal framework. The scope of the study comprised sheltered and exposed sites of three reefs along a cross-shelf gradient and over four seasons of the year. Calcification of all coral genera was consistent across the shelf and highest in spring. In addition, Pocillopora showed increased calcification at exposed reef sites. In contrast, CC calcification increased from nearshore, sheltered to offshore, exposed reef sites, but also varied over seasons. Comparing our data to other reef locations, calcification in the Red Sea was in the range of data collected from reefs in the Caribbean and Indo-Pacific; however, Acropora calcification estimates were at the lower end of worldwide rates. Our study shows that the increasing coral cover from nearshore to offshore environments aligned with CC calcification but not coral calcification, highlighting the potentially important role of CC in structuring reef cover and habitats. While coral calcification maxima have been typically observed during summer in many reef locations worldwide, calcification maxima during spring in the central Red Sea indicate that summer temperatures exceed the optima of reef calcifiers in this region. This study provides a foundation for comparative efforts and sets a baseline to quantify impact of future environmental change in the central Red Sea.

  16. Spatial and seasonal reef calcification in corals and calcareous crusts in the central Red Sea

    KAUST Repository

    Roik, Anna Krystyna

    2015-12-14

    The existence of coral reef ecosystems critically relies on the reef carbonate framework produced by scleractinian corals and calcareous crusts (i.e., crustose coralline algae). While the Red Sea harbors one of the longest connected reef systems in the world, detailed calcification data are only available from the northernmost part. To fill this knowledge gap, we measured in situ calcification rates of primary and secondary reef builders in the central Red Sea. We collected data on the major habitat-forming coral genera Porites, Acropora, and Pocillopora and also on calcareous crusts (CC) in a spatio-seasonal framework. The scope of the study comprised sheltered and exposed sites of three reefs along a cross-shelf gradient and over four seasons of the year. Calcification of all coral genera was consistent across the shelf and highest in spring. In addition, Pocillopora showed increased calcification at exposed reef sites. In contrast, CC calcification increased from nearshore, sheltered to offshore, exposed reef sites, but also varied over seasons. Comparing our data to other reef locations, calcification in the Red Sea was in the range of data collected from reefs in the Caribbean and Indo-Pacific; however, Acropora calcification estimates were at the lower end of worldwide rates. Our study shows that the increasing coral cover from nearshore to offshore environments aligned with CC calcification but not coral calcification, highlighting the potentially important role of CC in structuring reef cover and habitats. While coral calcification maxima have been typically observed during summer in many reef locations worldwide, calcification maxima during spring in the central Red Sea indicate that summer temperatures exceed the optima of reef calcifiers in this region. This study provides a foundation for comparative efforts and sets a baseline to quantify impact of future environmental change in the central Red Sea.

  17. Provenance of Holocene calcareous beach-dune sediments, Western Eyre Peninsula, Great Australian Bight, Australia

    Science.gov (United States)

    James, Noel P.; Bone, Yvonne

    2017-07-01

    Much of western Eyre Peninsula adjacent to the Great Australian Bight is veneered with siliceous and calcareous Quaternary aeolian dunes. The lengthy coastline adjacent to this cool-water carbonate factory is a series of Precambrian crystalline bedrock-Pleistocene aeolianite headlands that separate many long, sweeping, Holocene carbonate sand beaches and their backbeach dunes. Incessant SW waves, rolling swells, and onshore winds have resulted in > 350 km of semi-continuous calcareous strandline aeolian sands. The sediment is composed of quartz grains, Cenozoic limestone clasts, and relict particles (extraclasts) but the deposits are overwhelmingly dominated by contemporaneous biofragments from offshore. These skeletal grains are, in order of relative abundance, molluscs > benthic foraminifers > coralline algae > bryozoans, and echinoids. Benthic foraminifers are mostly small (especially rotaliids and miliolids) but the large relict symbiont-bearing protistMarginopora vertebralis, which grew in the latter stages of MIS 2, is present locally. There are no significant onshore-offshore trends within individual beach-dune complexes. There is, however, a prominent spatial partitioning, with extraclast-rich sediments in the north and biofragment-rich deposits in the south. This areal trend is interpreted to result from more active seafloor carbonate production in the south, an area of conspicuous seasonal nutrient upwelling and profound nektic and benthic biological productivity. The overall system is strikingly similar to Holocene and Pleistocene aeolianites along the inboard margin of the Lacepede Shelf and Bonney Coast some 500 km to the southeast, implying a potential universality to the nature of cool-water carbonate aeolianite deposition. The composition of these cool-water aeolianites is more multifaceted than those formed on warm-water, shallow flat-topped platforms, largely because of the comparatively deep, temperate shelf, the high-energy wave and swell

  18. CALCAREOUS NANNOFOSSIL BIOSTRATIGRAPHY OF UPPER CALLOVIAN-LOWER BERRIASIAN SUCCESSIONS FROM THE SOUTHERN ALPS, NORTH ITALY

    Directory of Open Access Journals (Sweden)

    CRISTINA EMANUELA CASELLATO

    2010-11-01

    Full Text Available Calcareous nannofossil biostratigraphy was investigated in uppermost Callovian-lower Berriasian sections from Southern Alps, previously detected through magnetostratigraphy, in order to achieve an integrated stratigraphic framework valid at low latitudes. Nannofossil investigations were carried out on smear slides and ultra-thin sections, revealing generally scarce to common abundances and poor-moderate preservation of nannofloras. An exhaustive taxonomic revision was performed to unambiguously separate forms which are transitional between two species and better delineate rapidly evolving groups. Four new species have been described: Zeugrhabdotus fluxus, Nannoconus puer, Nannoconus erbae, Hexalithus geometricus. Particular attention was paid to taxonomical aspects of primitive nannoconids, appearing and evolving across the early-late Tithonian transition and the Tithonian/Berriasian boundary intervals; the revision was also verified at DSDP Site 534A from Atlantic Ocean. Fourty-eight nannofossil bioevents were detected and the results help to increase potential stratigraphic resolution in this interval. Thirty-seven nannofossil bioevents in the upper Kimmeridgian-lower Berriasian interval have been directly correlated to magnetostratigraphy (CM22-CM17 revealing a systematically older stratigraphic occurrence of these taxa than previously reported. A revised and partly new Tethyan calcareous nannofossil zonation scheme is here proposed for the uppermost Callovian-lower Berriasian interval. It consists of seven bio-zones and eight subzones based on thirty-one bioevents, thirteen of them related to dissolution resistant taxa assuring highest reproducibility even in sections with high diagenetic overprint. The proposed biostratigraphic scheme gives higher resolution than previous zonations, especially for the Callovian-Kimmeridgian interval, where no biozonation was available for the Tethyan Realm. 

  19. Effect of Sulfur Application on Spinach Phytoremedaiton Process of Cadmium in Contaminated Calcareous Soils

    Directory of Open Access Journals (Sweden)

    Ali Kasraian

    2012-07-01

    Full Text Available Recently, cadmium (Cd concentration has increased in croplands through sewage sludge and phosphorous fertilizers application. On the other hand, some special methods, like phytoremedation, were introduced in order to decrease soil contamination hazard. Calcium carbonate plays an important role in Cd solubility in highly calcareous soils. Sulfurs oxidation, by dissolving Cd carbonate fraction, may improve phytoremediation efficiency. An experiment was conducted to study the effects of S application (equivalent to 0, 2, 4 and 6 Mg S ha-1 on Diethylene Triamine Pentaacetic Acid  (DTPA extractable Cd and also on Cd uptake and extraction by spinach (Spinacea oleracea L. in calcareous soils which were contaminated by 40mg Cd kg-1. To ensure biological S oxidation, all S-treated samples were inoculated by Thiobacillus spp. and incubated for 50 days. The soil pH, EC and soluble sulfate were affected by S application and it clearly showed that S oxidation process was occurred in Cd treated soils. The most significant change for pH and sulfate were observed at 4 Mg S ha-1 and for electrical conductivity (EC of soil it occurred at 6Mg S ha-1. Application of S had no effect on DTPA extractable Cd in soils whereas; its concentration increased 73.55% in average in plant tissue. Plant dry matter decreased significantly (about 63 percent following Cd application. Although the highest rate of S oxidation was observed at 4 and 6 Mg S ha-1 tٰٰٰhe maximum Cd extraction (2.5µg Cd pot-1 was observed at 2 Mg S ha-1 . This may be due to adverse effect of Cd toxicity and increase of soluble salt resulted by S oxidation in higher level of S application.

  20. The Role of Organic Acids on the Release of Phosphorus and Zinc in a Calcareous Soil

    Directory of Open Access Journals (Sweden)

    Sareh Nezami

    2017-02-01

    Full Text Available Introduction: Phosphorus (P and zinc (Zn fixation by soil minerals and their precipitation is one of the major constraints for crop production in calcareous soils. Recent Studies show that root exudates are effective for the extraction of the large amounts of nutrients in calcareous soils. A part of the root exudations are Low Molecular Weight Organic Acids (LMWOAs. LMWOAs are involved in the nutrients availability and uptake by plants, nutrients detoxification, minerals weathering and microbial proliferation in the soil. At nutrients deficiency conditions citric and oxalic acids are released by plants root in large quantities and increase nutrient solubility like P, Zn, Fe, Mn and Cu in the rhizosphere. These components are the large portion of the carbon source in the soil after exudations are mineralized by microorganisms, quickly. In addition, soil surface sorption can affect their half-life and other behaviors in the soil. In order to study the effect of oxalic and citric organic acids on the extraction of phosphorus and zinc from a calcareous soil, an experiment was conducted. Materials and Methods: Studied soil was calcareous and had P and Zn deficiency. Soil sample was collected from A horizon (0-30 cm of Damavand region. 3 g of dried soil sample was extracted with 30 ml of oxalic and citric acids extraction solutions at different concentrations (0.1, 1 and 10 mM and different time periods (10, 60, 180 and 360 minutes on an orbital shaker at 200 rev min-1.The soil extracts then centrifuged for 10 minutes (16000g. After filtering, the pH of the extractions was recorded and then phosphorus, calcium and zinc amounts were determined. Soil extraction with distilled water was used as control. Each treatment was performed in 3 replications. Statistical analysis was performed with ANOVA test followed by the Bonferroni method significant level adjustments due to multiple comparisons. Results and Discussion: The results of variance analysis showed

  1. Effect of three Electron Shuttles on Bioreduction of Ferric Iron in two Acidic and Calcareous soils

    Directory of Open Access Journals (Sweden)

    Setareh Sharifi

    2017-01-01

    Full Text Available Introduction: Iron cycle is one of the most important biogeochemical processes which affect the availability of iron in soils. Ferric iron oxides are the most abundant forms of iron in soils and sediments. Ferric iron is highly insoluble at circumneutral pH. Present investigations have shown that the structural ferric iron bound in clay minerals is reduced by some microorganisms. Anaerobic bacteria reduce ferric iron which bound to soil clay minerals under anaerobic conditions. They have the ability to use ferric iron as a terminal electron acceptor. Many studies presented that dissimilatory iron reducing bacteria (DIRB mediate the transfer of electrons from small organic molecules like acetate and glucose to various humic materials (electron shuttles which then pass electrons abiotically to ferric iron oxyhydroxide and phyllosilicate minerals. Electron shuttles like AQDS, a tricyclic quinone, increase the rate of iron reduction by iron reducing bacteria on sites of iron oxides and oxyhydroxides. By increasing the rate of bioreduction of ferric iron, the solubility and availability of iron enhanced meaningfully. Royer et al. (2002 showed that bioreduction of hematite (common iron mineral in soils increased more than three times in the presence of AQDS and Shewanella putrefaciens comparedto control treatments. Previous works have mostly used synthetic minerals as electron acceptor in bioreduction process. Furthermore, the effect of quinones as electron acceptor for microorganisms were studied with poorly crystalline ferric iron oxides . The main objective of this study was to study the effect of AQS, humic acid and fulvic acid (as electron shuttle and Shewanella sp. and Pseudomonas aeruginosa, on bioreduction of native ferric iron in two acidic and calcareous soils. Materials and Methods: An experiment was conducted in a completely randomized design with factorial arrangement and three replications in vitro condition. The soil samples collected

  2. Two new species of calcareous sponges (Porifera: Calcarea) from the deep Antarctic Eckström Shelf and a revised list of species found in Antarctic waters

    DEFF Research Database (Denmark)

    Rapp, Hans Tore; Göcke, Christian; Tendal, Ole Secher

    2013-01-01

    The paper reports on two new species of calcareous sponges (Porifera, Calcarea) from the Antarctic Weddell Sea, Clathrina brandtae sp. nov. and Leucetta delicata sp. nov., collected at 600 m depth during the ANT XXIV/2-SYSTCO expedition in January 2008. The new species are described based...... on a combination of morphological and molecular data. With these new additions the number of species of calcareous sponges reported from south of 50 degrees S (similar to south of the Polar Front) reaches 50 species. We report an exceptionally high degree of endemism within the group, and as many as 44 out...... of the 50 species of calcareous sponges are solely confined to Antarctic waters. An updated list of species of calcareous sponges from the area is provided....

  3. Using multi-proxy palaeoecology to test a relict status of refugial populations of calcareous-fen species in the Western Carpathians

    Czech Academy of Sciences Publication Activity Database

    Hájková, Petra; Horsák, M.; Hájek, Michal; Jankovská, Vlasta; Jamrichová, Eva; Moutelíková, J.

    2015-01-01

    Roč. 25, č. 4 (2015), s. 702-715 ISSN 0959-6836 Institutional support: RVO:67985939 Keywords : biodiversity * calcareous fen * fossil record * Holocene extinction * Western Carpathians Subject RIV: EF - Botanics Impact factor: 2.135, year: 2015

  4. On the nature of the calcareous substrate of a ferromanganese crust from the Vityaz Fracture Zone, Central Indian Ridge: Inferences on palaeoceanography

    Digital Repository Service at National Institute of Oceanography (India)

    Guptha, M.V.S.; Banerjee, R.; Mergulhao, L.

    A 15-cm-thick carbonate substrate encrusted with ferromanganese oxides from the Vityaz Fracture Zone, Central Indian Ridge was analysed to reconstruct the palaeoceanography of the region. Based on the calcareous nannoplankton assemblage, an early...

  5. Zinc solubility and fractionation in cultivated calcareous soils irrigated with wastewater

    Energy Technology Data Exchange (ETDEWEB)

    Nazif, W. [Division of Agricultural and Environmental Sciences, School of Biosciences, University of Nottingham, Sutton Bonington, Leicestershire LE12 5RD (United Kingdom); Marzouk, E.R. [Division of Soil and Water Sciences, Faculty of Environmental Agricultural Sciences, Suez Canal University, North Sinai 45516 (Egypt); Perveen, S. [Department of Soil and Environmental Sciences, Khyber Pakhtunkhwa Agricultural University, Peshawar (Pakistan); Crout, N.M.J. [Division of Agricultural and Environmental Sciences, School of Biosciences, University of Nottingham, Sutton Bonington, Leicestershire LE12 5RD (United Kingdom); Young, S.D., E-mail: scott.young@nottingham.ac.uk [Division of Agricultural and Environmental Sciences, School of Biosciences, University of Nottingham, Sutton Bonington, Leicestershire LE12 5RD (United Kingdom)

    2015-06-15

    The solubility, lability and fractionation of zinc in a range of calcareous soils from Peshawar, Pakistan were studied (18 topsoils and 18 subsoils). The lability (E-value) of Zn was assessed as the fraction isotopically exchangeable with {sup 70}Zn{sup 2+}; comparative extractions included 0.005 M DTPA, 0.43 M HNO{sub 3} and a Tessier-style sequential extraction procedure (SEP). Because of the extremely low concentration of labile Zn the E-value was determined in soils suspended in 0.0001 M Na{sub 2}-EDTA which provided reliable analytical conditions in which approximately 20% of the labile Zn was dissolved. On average, only 2.4% of soil Zn was isotopically exchangeable. This corresponded closely to Zn solubilised by extraction with 0.005 DTPA and by the carbonate extraction step (F1 + F2) of the Tessier-style SEP. Crucially, although the majority of the soil CaCO{sub 3} was dissolved in F2 of the SEP, the DTPA dissolved only a very small proportion of the soil CaCO{sub 3}. This suggests a superficial carbonate-bound form of labile Zn, accessible to extraction with DTPA and to isotopic exchange. Zinc solubility from soil suspended in 0.01 M Ca(NO{sub 3}){sub 2} (PCO{sub 2} controlled at 0.03) was measured over three days. Following solution speciation using WHAM(VII) two simple solubility models were parameterised: a pH dependent ‘adsorption’ model based on the labile (isotopically exchangeable) Zn distribution coefficient (Kd) and an apparent solubility product (Ks) for ZnCO{sub 3}. The distribution coefficient showed no pH-dependence and the solubility model provided the best fit to the free ion activity (Zn{sup 2+}) data, although the apparent value of log{sub 10} Ks (5.1) was 2.8 log units lower than that of the mineral smithsonite (ZnCO{sub 3}). - Highlights: • Isotopically exchangeable Zn in the calcareous soils of Peshawar is extremely low. • There is no evidence of topsoil enrichment from the use of wastewater for irrigation. • Solubility

  6. Zinc solubility and fractionation in cultivated calcareous soils irrigated with wastewater

    International Nuclear Information System (INIS)

    Nazif, W.; Marzouk, E.R.; Perveen, S.; Crout, N.M.J.; Young, S.D.

    2015-01-01

    The solubility, lability and fractionation of zinc in a range of calcareous soils from Peshawar, Pakistan were studied (18 topsoils and 18 subsoils). The lability (E-value) of Zn was assessed as the fraction isotopically exchangeable with 70 Zn 2+ ; comparative extractions included 0.005 M DTPA, 0.43 M HNO 3 and a Tessier-style sequential extraction procedure (SEP). Because of the extremely low concentration of labile Zn the E-value was determined in soils suspended in 0.0001 M Na 2 -EDTA which provided reliable analytical conditions in which approximately 20% of the labile Zn was dissolved. On average, only 2.4% of soil Zn was isotopically exchangeable. This corresponded closely to Zn solubilised by extraction with 0.005 DTPA and by the carbonate extraction step (F1 + F2) of the Tessier-style SEP. Crucially, although the majority of the soil CaCO 3 was dissolved in F2 of the SEP, the DTPA dissolved only a very small proportion of the soil CaCO 3 . This suggests a superficial carbonate-bound form of labile Zn, accessible to extraction with DTPA and to isotopic exchange. Zinc solubility from soil suspended in 0.01 M Ca(NO 3 ) 2 (PCO 2 controlled at 0.03) was measured over three days. Following solution speciation using WHAM(VII) two simple solubility models were parameterised: a pH dependent ‘adsorption’ model based on the labile (isotopically exchangeable) Zn distribution coefficient (Kd) and an apparent solubility product (Ks) for ZnCO 3 . The distribution coefficient showed no pH-dependence and the solubility model provided the best fit to the free ion activity (Zn 2+ ) data, although the apparent value of log 10 Ks (5.1) was 2.8 log units lower than that of the mineral smithsonite (ZnCO 3 ). - Highlights: • Isotopically exchangeable Zn in the calcareous soils of Peshawar is extremely low. • There is no evidence of topsoil enrichment from the use of wastewater for irrigation. • Solubility products for smithsonite and hydrozincite fail to describe Zn 2

  7. Distinguishing Biologically Controlled Calcareous Biomineralization in Fossil Organisms Using Electron Backscatter Diffraction (EBSD)

    Science.gov (United States)

    Päßler, Jan-Filip; Jarochowska, Emilia; Bestmann, Michel; Munnecke, Axel

    2018-02-01

    Although carbonate-precipitating cyanobacteria are ubiquitous in aquatic ecosystems today, the criteria used to identify them in the geological record are subjective and rarely testable. Differences in the mode of biomineralization between cyanobacteria and eukaryotes, i.e. biologically induced calcification (BIM) vs. biologically controlled calcification (BCM), result in different crystallographic structures which might be used as a criterion to test cyanobacterial affinities. Cyanobacteria are often used as a ‘wastebasket taxon’, to which various microfossils are assigned. The lack of a testable criterion for the identification of cyanobacteria may bias their fossil record severely. We employed electron backscatter diffraction (EBSD) to investigate the structure of calcareous skeletons in two microproblematica widespread in Palaeozoic marine ecosystems: Rothpletzella, hypothesized to be a cyanobacterium, and an incertae sedis microorganism Allonema. We used a calcareous trilobite shell as a BCM reference. The mineralized structure of Allonema has a simple single-layered structure of acicular crystals perpendicular to the surface of the organism. The c-axes of these crystals are parallel to the elongation and thereby normal to the surface of the organism. EBSD pole figures and misorientation axes distribution reveal a fibre texture around the c-axis with a small degree of variation (up to 30°), indicating a highly ordered structure. A comparable pattern was found in the trilobite shell. This structure allows excluding biologically induced mineralization as the mechanism of shell formation in Allonema. In Rothpletzella, the c-axes of the microcrystalline sheath show a broader clustering compared to Allonema, but still reveal crystals tending to be perpendicular to the surface of the organism. The misorientation axes of adjacent crystals show an approximately random distribution. Rothpletzella also shares morphological similarities with extant cyanobacteria. We

  8. Productivity response of calcareous nannoplankton to Eocene Thermal Maximum 2 (ETM2

    Directory of Open Access Journals (Sweden)

    M. Dedert

    2012-05-01

    Full Text Available The Early Eocene Thermal Maximum 2 (ETM2 at ~53.7 Ma is one of multiple hyperthermal events that followed the Paleocene-Eocene Thermal Maximum (PETM, ~56 Ma. The negative carbon excursion and deep ocean carbonate dissolution which occurred during the event imply that a substantial amount (103 Gt of carbon (C was added to the ocean-atmosphere system, consequently increasing atmospheric CO2(pCO2. This makes the event relevant to the current scenario of anthropogenic CO2 additions and global change. Resulting changes in ocean stratification and pH, as well as changes in exogenic cycles which supply nutrients to the ocean, may have affected the productivity of marine phytoplankton, especially calcifying phytoplankton. Changes in productivity, in turn, may affect the rate of sequestration of excess CO2 in the deep ocean and sediments. In order to reconstruct the productivity response by calcareous nannoplankton to ETM2 in the South Atlantic (Site 1265 and North Pacific (Site 1209, we employ the coccolith Sr/Ca productivity proxy with analysis of well-preserved picked monogeneric populations by ion probe supplemented by analysis of various size fractions of nannofossil sediments by ICP-AES. The former technique of measuring Sr/Ca in selected nannofossil populations using the ion probe circumvents possible contamination with secondary calcite. Avoiding such contamination is important for an accurate interpretation of the nannoplankton productivity record, since diagenetic processes can bias the productivity signal, as we demonstrate for Sr/Ca measurements in the fine (<20 μm and other size fractions obtained from bulk sediments from Site 1265. At this site, the paleoproductivity signal as reconstructed from the Sr/Ca appears to be governed by cyclic changes, possibly orbital forcing, resulting in a 20–30% variability in Sr/Ca in dominant genera as obtained by ion probe. The ~13 to 21

  9. The Eocene Rusayl Formation, Oman, carbonaceous rocks in calcareous shelf sediments: Environment of deposition, alteration and hydrocarbon potential

    Energy Technology Data Exchange (ETDEWEB)

    Dill, H.G.; Wehner, H.; Kus, J. [Federal Institute for Geosciences and Natural Resources, P.O. Box 510163, D-30631 Hannover (Germany); Botz, R. [University Kiel, Geological-Paleontological Department, Olshausenstrasse 40-60, D-24118 Kiel (Germany); Berner, Z.; Stueben, D. [Technical University Karlsruhe, Institute for Mineralogy and Geochemistry, Fritz-Haber-Weg 2, D-76131 Karlsruhe (Germany); Al-Sayigh, A. [Sultan Qaboos University, Geological Dept. PO Box 36, Al-Khod (Oman)

    2007-10-01

    Paralic carbonaceous series intercalated among calcareous shelf sediments have seldom been investigated. During the early Eocene, calcareous and siliciclastic sediments were deposited on a wide shelf in front of low-reliefed hinterland in the Al Khawd region in NE Oman. The siliciclastic-calcareous sediments originated from strongly reworked debris of the Arabic Shield. The underlying Semail Ophiolite did not act as a direct source of debris but provided some heat to increase the maturity of carbonaceous rocks and modify the isotope signal of the calcareous minerals in the Rusayl Formation. A multidisciplinary approach involving sedimentology, mineralogy, chemistry, coal petrography and paleontology resulted in the establishment of nine stratigraphic lithofacies units and provides the reader with a full picture from deposition of the mixed carbonaceous-calcareous-siliciclastic rocks to the most recent stages of post-depositional alteration of the Paleogene formations. The calcareous Jafnayn Formation (lithofacies unit I) developed in a subtidal to intertidal regime, influenced episodically by storms. Deepening of the calcareous shelf towards younger series was ground to a halt by paleosols developing on a disconformity (lithofacies unit II) and heralding the onset of the Rusayl Formation. The stratigraphic lithofacies units III and IV reflect mangrove swamps which from time to time were flooded through washover fans from the open sea. The presence of Spinozonocolpites and the taxon Avicennia, which today belong to a coastal marsh vegetational community, furnish palynological evidence to the idea of extensive mangrove swamps in the Rusayl Formation [El Beialy, S.Y., 1998. Stratigraphic and palaeonenvironmental significance of Eocene palynomorphs from the Rusayl Shale Formation, Al Khawd, northern Oman. Review of Palaeobotany and Palynology 102, 249-258]. During the upper Rusayl Formation (lithofacies units V through VII) algal mats episodically flooded by marine

  10. Paleocene calcareous nannofossils biostratigraphy from the Sergipe Sub-basin, northeastern Brazil: Implications for this depositional environment

    Science.gov (United States)

    Andrade Oliveira, Geize Carolinne Correia; de Oliveira, Rick Souza; Monte Guerra, Rodrigo; de Lima Filho, Mario Ferreira

    2018-03-01

    This study reports on the biostratigraphy of Paleocene calcareous nannofossils and paleoenvironmental inferences based on five wells drilled on the offshore portion of the Sergipe Sub-basin. Five biostratigraphic zones were defined for the Paleocene in zones of Brazilian continental margin basins N-305, N-307, N-330, N-340 and N-350, and four hiatuses were identified based on the absence of marker species. These hiatuses were interpreted as excavations originated by turbulent to hyperpycnal flows, revealing an important application of biostratigraphy to better understand depositional environments that are often limited by little variation in lithology or low variation in the well log patterns. In Paleoecological terms, the Sergipe Sub-basin, in the Paleocene, experienced geological and environmental events similar to those of other sedimentary basins on the eastern passive continental margin of Brazil, but has a more complete biostratigraphic record of calcareous nannofossils.

  11. Ca (OH)2Nanoparticles Based on Acrylic Copolymers for the consolidation and protection of Ancient Egypt Calcareous Stone Monuments

    Science.gov (United States)

    Al-Dosari, Mohammad A.; Darwish, Sawsan S.; Adam, Mahmoud A.; Elmarzugi, Nagib A.; Al-Mouallimi, Nadia; Ahmed, Sayed M.

    2017-04-01

    The deterioration of calcareous stones materials used in artistic/architectural field is one of the most serious problems facing conservation today. The aim of this study was to evaluate the effectiveness of nanosized particles of calcium hydroxide (slaked lime) as a consolidation and protection material dispersed in acrylic copolymer, poly ethylmethacrylate/methylacrylate (70:30) (Poly (EMA/MA), for calcareous stone monuments and painted surfaces affected by different kinds of decay. The synthesis process of Ca (OH)2 nanoparticles/polymer nanocomposites have been prepared by in situ emulsion polymerization system. The prepared nanocomposite containing 5% of Ca (OH)2 nanoparticles showed obvious transparency features and represent nanocomposites coating technology with hydrophobic, consolidating and well protection properties.

  12. Phosphorus availability due to polyphosphates additions to alfalfa plants grown on alluvial and calcareous soils using tracer techniques

    International Nuclear Information System (INIS)

    Ismail, A.S.; Massoud, M.A.; Shalil, K.M.E.

    1985-01-01

    A pot experiment was carried out to compare the effect of different sources and levels of condensed phosphates, including ring and chain structured molecules, with orthophosphate on alfalfa plants grown on alluvial and highly calcareous soils using P-32-labelled fertilizers. Data indicate that application of different sources of P-fertilizers increased both dry matter content and total-P uptake by alfalfa plants over control in both soils. The fraction of phosphorus in plants derived from added fertilizers was higher from condensed phosphates than that derived from the other sources of phosphorus. The percentages of P-fraction derived from added fertilizers (y-values) were higher in calcareous soil than those in alluvial soil

  13. Ca (OH)2Nanoparticles Based on Acrylic Copolymers for the consolidation and protection of Ancient Egypt Calcareous Stone Monuments

    International Nuclear Information System (INIS)

    Al-Dosari, Mohammad A.; Ahmed, Sayed M.; Darwish, Sawsan S.; Adam, Mahmoud A.; Elmarzugi, Nagib A.; Al-Mouallimi, Nadia

    2017-01-01

    The deterioration of calcareous stones materials used in artistic/architectural field is one of the most serious problems facing conservation today. The aim of this study was to evaluate the effectiveness of nanosized particles of calcium hydroxide (slaked lime) as a consolidation and protection material dispersed in acrylic copolymer, poly ethylmethacrylate/methylacrylate (70:30) (Poly (EMA/MA), for calcareous stone monuments and painted surfaces affected by different kinds of decay. The synthesis process of Ca (OH) 2 nanoparticles/polymer nanocomposites have been prepared by in situ emulsion polymerization system. The prepared nanocomposite containing 5% of Ca (OH) 2 nanoparticles showed obvious transparency features and represent nanocomposites coating technology with hydrophobic, consolidating and well protection properties. (paper)

  14. A preliminary spatial-temporal study of some soil characteristics in the calcareous massif of Sicó, Portugal.

    Science.gov (United States)

    Torres, Maria Odete; Neves, Maria Manuela

    2016-04-18

    The mountainous massif of Sicó, in the centre of Portugal, is an extensive area composed of calcareous Jurassic formations. Hillside calcareous soils, with high pH, present chemical restrictions to support plant growth and are subjected to important erosion processes leading to their degradation if not protected by vegetation. In a first year of study some soil physicochemical characteristics have been measured in some geo-referenced locations of a larger design experiment and an exploratory spatial analysis has been performed. The objective of this study was to present some suggestions in order to give sustainable phosphorus fertiliser recommendations aiming to establish pastures in these soils and thus support traditional livestock activity. Ten years apart, those soil characteristics have been measured again in the same locations and comparisions have been made. The objective was to understand the variability of the soil properties under study in order to better adequate the fertiliser soil management regarding the area restoration.

  15. Kinetic behavior of Fe(o,o-EDDHA)-humic substance mixtures in several soil components and in calcareous soils.

    Science.gov (United States)

    Cerdán, Mar; Alcañiz, Sara; Juárez, Margarita; Jordá, Juana D; Bermúdez, Dolores

    2007-10-31

    Ferric ethylenediamine- N, N'-bis-(o-hydroxyphenylacetic)acid chelate (Fe(o, o-EDDHA)) is one of the most effective Fe fertilizers in calcareous soils. However, humic substances are occasionally combined with iron chelates in drip irrigation systems in order to lower costs. The reactivity of iron chelate-humic substance mixtures in several soil components and in calcareous soils was investigated through interaction tests, and their behavior was compared to the application of iron chelates and humic substances separately. Two commercial humic substances and two Fe(o, o-EDDHA) chelates (one synthesized in the laboratory and one commercial) were used to prepare iron chelate-humic substance mixtures at 50% (w/w). Various soil components (calcium carbonate, gibbsite, amorphous iron oxide, hematite, tenorite, zincite, amorphous Mn oxide, and peat) and three calcareous soils were shaken for 15 days with the mixtures and with iron chelate and humic substance solutions. The kinetic behavior of Fe(o, o-EDDHA) and Fe non-(o,o-EDDHA) (Fe bonded to (o,p-EDDHA) and other polycondensated ligands) and of the different nutrients solubilized after the interaction assay was determined. The results showed that the mixtures did not significantly reduce the retention of Fe(o, o-EDDHA) and Fe non-(o,o-EDDHA) in the soil components and the calcareous soils compared to the iron chelate solutions, but they did produce changes in the retention rate. Moreover, the competition between humic substances and synthetic chelating agents for complexing metal cations limited the effectiveness of the mixtures to mobilize nutrients from the substrates. The presence of Fe(o, p-EDDHA) and other byproducts in the commercial iron chelate had an important effect on the evolution of Fe(o, o-EDDHA) and the nutrient solubilization process.

  16. Uranium geochemistry in a calcareous peat: mineral-organic-microorganisms interactions and implications on uranium mobility in a contaminated soil

    International Nuclear Information System (INIS)

    Phrommavanh, V.; Descostes, M.; L'Orphelin, J.M.; Beaucaire, C.; Gaudet, J.P.

    2009-01-01

    The authors discuss the different approaches and techniques which have been implemented to study the behaviour of uranium in an as complex medium as a natural peat, in this case, a calcareous peat located on an old industrial site which was dedicated to uranium processing and which is now being decontaminated. They report and comment a chemical and mineralogical characterization of this peat, its hydrochemical characterization, and a microbial flora characterization

  17. Effect of Arbuscular Mycorrhizae on zinc nutrition of maize grow in calcareous soil amended with different phosphorus sources

    International Nuclear Information System (INIS)

    Aly, S.S.M.; EL-Ghandour, I. A.

    2001-01-01

    Arbuscular mycorrhizal fungi (AMF) are known to improve P nutrition of plants. The information of AMF effects on corn Zn nutrition under P fertilization in calcareous soil is limited. A greenhouse experiment was carried out using calcareous soil and two P-sources i.e single superphosphate and rock phosphate (with full and one third of recommended dose). to evaluate the ability of AMF on improving Zn nutrition in maize plants. Labelled 65 ZnSo 4 was added at rates of 0.10 and 20 mg Zn Kg -1 soil. Zinc uptake and dry mater of corn shoots were improved as a result of AMF inoculation. The maximum improvement was recorded with super-P fertilizer in combination with 10 or 20 mg Zn Kg -1 soil for non-inoculated and AMF inoculated plants. respectively. The amount of Zn in non-inoculated and AMF inoculated plants. respectively. The amount of ZnSo 4 utilized plant derived from fertilizer.(Zndff) and the percent of ZnSo 4 utilization by corn plants were increased when ZnSo 4 was added at rate of 10 mg Zn Kg -1 soil in the presence of super-P fertilizer. Inoculated plants with AMF had higher Zndff content and U% than non-inoculated ones and the greater Zndff and superphosphate fertilizer. It could be concluded that. AMF is useful method utilization by corn plants grown in calcareous soil

  18. EDTA and HCl leaching of calcareous and acidic soils polluted with potentially toxic metals: remediation efficiency and soil impact.

    Science.gov (United States)

    Udovic, Metka; Lestan, Domen

    2012-07-01

    The environmental risk of potentially toxic metals (PTMs) in soil can be diminished by their removal. Among the available remediation techniques, soil leaching with various solutions is one of the most effective but data about the impact on soil chemical and biological properties are still scarce. We studied the effect of two common leaching agents, hydrochloric acid (HCl) and a chelating agent (EDTA) on Pb, Zn, Cd removal and accessibility and on physico-chemical and biological properties in one calcareous, pH neutral soil and one non-calcareous acidic soil. EDTA was a more efficient leachant compared to HCl: up to 133-times lower chelant concentration was needed for the same percentage (35%) of Pb removal. EDTA and HCl concentrations with similar PTM removal efficiency decreased PTM accessibility in both soils but had different impacts on soil properties. As expected, HCl significantly dissolved carbonates from calcareous soil, while EDTA leaching increased the pH of the acidic soil. Enzyme activity assays showed that leaching with HCl had a distinctly negative impact on soil microbial and enzyme activity, while leaching with EDTA had less impact. Our results emphasize the importance of considering the ecological impact of remediation processes on soil in addition to the capacity for PTM removal. Copyright © 2012 Elsevier Ltd. All rights reserved.

  19. Reactivity and effectiveness of traditional and novel ligands for multi-micronutrient fertilization in a calcareous soil.

    Science.gov (United States)

    López-Rayo, Sandra; Nadal, Paloma; Lucena, Juan J

    2015-01-01

    This study compares the effectiveness of multi-micronutrient formulations containing iron (Fe), manganese (Mn), and zinc (Zn) with traditional (EDTA, DTPA, HEEDTA, and EDDHAm) or novel chelates (o,p-EDDHA, S,S-EDDS, and IDHA) and natural complexing agents (gluconate and lignosulfonate). The stability and reactivity of the formulations were studied on batch experiments with calcareous soil and by speciation modeling. Formulations containing traditional ligands maintained higher Mn but lower Zn concentration in soil solution than the novel ligands. The gluconate and lignosulfonate maintained low concentrations of both Mn and Zn in soil solution. Selected formulations were applied into calcareous soil and their efficacy was evaluated in a pot experiment with soybean. The formulation containing DTPA led to the highest Zn concentration in plants, as well as the formulation containing S,S-EDDS in the short-term, which correlated with its biodegradability. The application of traditional or novel ligands in formulations did not result in sufficient plant Mn concentrations, which was related to the low Mn stability observed for all formulations under moderate oxidation conditions. The results highlight the need to consider the effect of metals and ligands interactions in multi-nutrient fertilization and the potential of S,S-EDDS to be used for Zn fertilization. Furthermore, it is necessary to explore new sources of Mn fertilization for calcareous soils that have greater stability and efficiency, or instead to use foliar fertilization.

  20. Reactivity and effectiveness of traditional and novel ligands for multi-micronutrient fertilization in a calcareous soil

    Directory of Open Access Journals (Sweden)

    Sandra eLópez-Rayo

    2015-09-01

    Full Text Available This study compares the effectiveness of multi-micronutrient formulations containing Fe, Mn, and Zn with traditional (EDTA, DTPA, HEEDTA, EDDHAm or novel chelates (o,p-EDDHA, S,S-EDDS, IDHA and natural complexing agents (gluconate and lignosulfonate. The stability and reactivity of the formulations were studied on batch experiments with calcareous soil and by speciation modeling. Formulations containing traditional ligands maintained higher Mn but lower Zn concentration in soil solution than the novel ligands. The gluconate and lignosulfonate maintained low concentrations of both Mn and Zn in soil solution. Selected formulations were applied into calcareous soil and their efficacy was evaluated in a pot experiment with soybean. The formulation containing DTPA led to the highest Zn concentration in plants, as well as the formulation containing S,S-EDDS in the short-term, which correlated with its biodegradability. The application of traditional or novel ligands in formulations did not result in sufficient plant Mn concentrations, which was related to the low Mn stability observed for all formulations under moderate oxidation conditions. The results highlight the need to consider the effect of metals and ligands interactions in multi-nutrient fertilization and the potential of S,S-EDDS to be used for Zn fertilization. Furthermore, it is necessary to explore new sources of Mn fertilization for calcareous soils that have greater stability and efficiency, or instead to use foliar fertilization.

  1. Crop Yield and Soil Properties in the First 3 Years After Biochar Application to a Calcareous Soil

    Institute of Scientific and Technical Information of China (English)

    LIANG Feng; LI Gui-tong; LIN Qi-mei; ZHAO Xiao-rong

    2014-01-01

    It remains unclear whether biochar applications to calcareous soils can improve soil fertility and crop yield. A long-term ifeld experiment was established in 2009 so as to determine the effect of biochar on crop yield and soil properties in a calcareous soil. Five treatments were: 1) straw incorporation; 2) straw incorporation with inorganic fertilizer; 3), 4) and 5) straw incorporation with inorganic fertilizer, and biochar at 30, 60, and 90 t ha-1, respectively. The annual yield of either winter wheat or summer maize was not increased signiifcantly following biochar application, whereas the cumulative yield over the ifrst 4 growing seasons was signiifcantly increased. Soil pH, measured in situ, was increased by a maximum of 0.35 units after 2 yr following biochar application. After 3 yr, soil bulk density signiifcantly decreased while soil water holding capacity increased with adding biochar of 90 t ha-1. Alkaline hydrolysable N decreased but exchangeable K increased due to biochar addition. Olsen-P did not change compared to the treatment without biochar. The results suggested that biochar could be used in calcareous soils without yield loss or signiifcant impacts on nutrient availability.

  2. Reactivity and effectiveness of traditional and novel ligands for multi-micronutrient fertilization in a calcareous soil

    Science.gov (United States)

    López-Rayo, Sandra; Nadal, Paloma; Lucena, Juan J.

    2015-01-01

    This study compares the effectiveness of multi-micronutrient formulations containing iron (Fe), manganese (Mn), and zinc (Zn) with traditional (EDTA, DTPA, HEEDTA, and EDDHAm) or novel chelates (o,p-EDDHA, S,S-EDDS, and IDHA) and natural complexing agents (gluconate and lignosulfonate). The stability and reactivity of the formulations were studied on batch experiments with calcareous soil and by speciation modeling. Formulations containing traditional ligands maintained higher Mn but lower Zn concentration in soil solution than the novel ligands. The gluconate and lignosulfonate maintained low concentrations of both Mn and Zn in soil solution. Selected formulations were applied into calcareous soil and their efficacy was evaluated in a pot experiment with soybean. The formulation containing DTPA led to the highest Zn concentration in plants, as well as the formulation containing S,S-EDDS in the short-term, which correlated with its biodegradability. The application of traditional or novel ligands in formulations did not result in sufficient plant Mn concentrations, which was related to the low Mn stability observed for all formulations under moderate oxidation conditions. The results highlight the need to consider the effect of metals and ligands interactions in multi-nutrient fertilization and the potential of S,S-EDDS to be used for Zn fertilization. Furthermore, it is necessary to explore new sources of Mn fertilization for calcareous soils that have greater stability and efficiency, or instead to use foliar fertilization. PMID:26442065

  3. Evolution of Calcareous Deposits and Passive Film on 304 Stainless Steel with Cathodic Polarization in Sea Water

    Directory of Open Access Journals (Sweden)

    Tianxiang Sun

    2018-05-01

    Full Text Available The change of protective current density, the formation and growth of calcareous deposits, and the evolution of passive film on 304 stainless steel (SS were investigated at different potentials of cathodic polarization in sea water. Potentiostatic polarization, electrochemical impedance spectroscopy (EIS, and surface analysis techniques of scanning electron microscopy (SEM, energy dispersive X-ray (EDX microanalysis and X-ray diffraction (XRD were used to characterize the surface conditions. It was found that the protective current density was smaller for keeping polarization at −0.80 V (vs. saturated calomel electrode (SCE, same as below than that at −0.65 V. The calcareous deposits could not be formed on 304 SS with polarization at −0.50 V while it was well protected. The formation rate, the morphology, and the constituent of the calcareous deposits depended on the applied potential. The resistance of passive film on 304 SS decreased at the first stage and then increased when polarized at −0.80 V and −0.65 V, which was related to the reduction and the repair of passive film. For the stainless steel polarized at −0.50 V, the film resistance increased with polarization time, indicating that the growth of oxide film was promoted.

  4. Long-range crystalline order in spicules from the calcareous sponge Paraleucilla magna (Porifera, Calcarea).

    Science.gov (United States)

    Rossi, Andre L; Campos, Andrea P C; Barroso, Madalena M S; Klautau, Michelle; Archanjo, Bráulio S; Borojevic, Radovan; Farina, Marcos; Werckmann, Jacques

    2014-09-01

    We investigated the ultrastructure and crystallographic orientation of spicules from the calcareous sponge Paraleucilla magna (subclass Calcaronea) by transmission and scanning electron microscopy using two different methods of sample preparation: ultramicrotomy and focused ion beam (FIB). It was found that the unpaired actine from the spicules was oriented in the [211] zone axis. The plane that contains the unpaired actine and divides symmetrically the paired actines is the (-120). This plane is a mirror plane of the hexagonal lattice system. All the spicule types analyzed presented the same crystallographic orientation. Electron nanodiffraction maps from 4μm×4μm regions prepared by FIB showed disorientation of <2° between diffraction patterns obtained from neighbor regions, indicating the presence of a unique, highly aligned calcite crystalline phase. Among the eight FIB sections obtained, four presented high pore density. In one section perpendicular to the actine axis pores were observed only in the center of the spicule aligned in a circular pattern and surrounded by a faint circular contour with a larger radius. The presence of amorphous carbon representative of organic molecules detected by electron energy loss spectroscopy was correlated neither with porosity nor with specific lattice planes. Copyright © 2014 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  5. Oxygen and carbon isotopes of Recent calcareous nannofossils as paleoceanographic indicators

    International Nuclear Information System (INIS)

    Goodney, D.E.; Margolis, S.V.; Dudley, W.C.; Kroopnick, P.; Williams, D.F.

    1980-01-01

    Delta 18 O and delta 13 C values for several species of planktonic foraminifera and calcareous nannofossils from Recent deep-sea sediments have been studied in order to evaluate their paleoceanographic and paleotemperature potential. Nannofossils from Indian Ocean core-tops reflect isotopic temperatures as warm as, or warmer than, the temperatures reported for shallow-dwelling planktonic forminifera from the same samples. In general, deep-sea sediment samples from the world's major oceans indicate that nannofossil delta 18 O values are from 0.5 to 1 per thousand heavier than shallow-dwelling planktonic foraminifera. Although nannofossil delta 18 O values depart from thermodynamic equilibrium with oceanic surface water temperatures, the delta 18 O temperature trend parallels that of surface-dwelling planktonic foraminifera. Nannofossil delta 13 C values also depart equilibrium with surface water delta 13 C-ΣCO 2 values. A comparison of nannofossil delta 13 C data with that from planktonic foraminifera suggests that the rate of primary productivity in different water masses may be influencing the delta 13 C carbonate-secreting phytoplankton and zooplankton. (Auth.)

  6. Influence of long-term fertilization on the selenium content of calcareous chernozem soil.

    Science.gov (United States)

    Blagojević, S; Jakovljević, M; Zarković, B

    1998-01-01

    Available data on the selenium (Se) content in Yugoslavian soils indicate that the element is present in small amounts (chernozem soil. The experiment of the Maize Research Institute in Belgrade was set up in 1971 and soil samples were examined by chemical analysis after 23 years. The following important conclusions can be drawn based on the analytical data obtained. The total content of Se in the investigated experimental variants in calcareous chernozem soil ranges from 166 to 593 microg/kg. All the variants had a higher content of Se than soil samples taken before the experiment was set up. Comparison with the control (variant without fertilizers) indicated that the Se content increased in the experimental variants where farmyard manure had been applied. This effect was noticed to a depth of 80 cm. Application of farmyard manure should be considered as a means of increasing the levels of Se in Se-deficient soil. Correlation coefficients between total Se content in the soil and some important agrochemical properties of the investigated soils are presented in this paper.

  7. Factors affecting cadmium absorbed by pistachio kernel in calcareous soils, southeast of Iran.

    Science.gov (United States)

    Shirani, H; Hosseinifard, S J; Hashemipour, H

    2018-03-01

    Cadmium (Cd) which does not have a biological role is one of the most toxic heavy metals for organisms. This metal enters environment through industrial processes and fertilizers. The main objective of this study was to determine the relationships between absorbed Cd by pistachio kernel and some of soil physical and chemical characteristics using modeling by stepwise regression and Artificial Neural Network (ANN), in calcareous soils in Rafsanjan region, southeast of Iran. For these purposes, 220 pistachio orchards were selected, and soil samples were taken from two depths of 0-40 and 40-80cm. Besides, fruit and leaf samples from branches with and without fruit were taken in each sampling point. The results showed that affecting factors on absorbed Cd by pistachio kernel which were obtained by regression method (pH and clay percent) were not interpretable, and considering unsuitable vales of determinant coefficient (R 2 ) and Root Mean Squares Error (RMSE), the model did not have sufficient validity. However, ANN modeling was highly accurate and reliable. Based on its results, soil available P and Zn and soil salinity were the most important factors affecting the concentration of Cd in pistachio kernel in pistachio growing areas of Rafsanjan. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. Effects of iron(III)chelates on the solubility of heavy metals in calcareous soils

    Energy Technology Data Exchange (ETDEWEB)

    Ylivainio, Kari, E-mail: kari.ylivainio@mtt.f [Department of Applied Chemistry and Microbiology, FIN-00014 University of Helsinki (Finland)

    2010-10-15

    In this study I evaluated the effects of complexing agents on the solubility of heavy metals in an incubation experiment up to 56 days when complexing agents were applied as Fe-chelates (Fe-EDDS(S,S), Fe-EDDS(mix), Fe-EDTA and Fe-EDDHA) on calcareous soils at a level sufficient to correct Fe chlorosis (0.1 mmol kg{sup -1}). Of these ligands, EDDHA was the most efficient in keeping Fe in water-soluble form, and EDDS increased the solubility of Cu and Zn most, and only EDTA increased the solubility of Cd and Pb. EDTA increased the solubility of Ni steadily during the incubation period, equalling about 5-8% of the added EDTA concentration. [S,S]-EDDS was biodegraded within 56 days, whereas EDDS(mix) was less biodegradable. Ni-chelates were the most recalcitrant against biodegradation. The study shows that even a moderate input of chelates to soil increases the solubility of toxic heavy metals and their risk of leaching. - When correcting Fe chlorosis Fe-EDDS causes lower environmental concern than Fe-EDTA.

  9. Effects of iron(III)chelates on the solubility of heavy metals in calcareous soils

    International Nuclear Information System (INIS)

    Ylivainio, Kari

    2010-01-01

    In this study I evaluated the effects of complexing agents on the solubility of heavy metals in an incubation experiment up to 56 days when complexing agents were applied as Fe-chelates (Fe-EDDS(S,S), Fe-EDDS(mix), Fe-EDTA and Fe-EDDHA) on calcareous soils at a level sufficient to correct Fe chlorosis (0.1 mmol kg -1 ). Of these ligands, EDDHA was the most efficient in keeping Fe in water-soluble form, and EDDS increased the solubility of Cu and Zn most, and only EDTA increased the solubility of Cd and Pb. EDTA increased the solubility of Ni steadily during the incubation period, equalling about 5-8% of the added EDTA concentration. [S,S]-EDDS was biodegraded within 56 days, whereas EDDS(mix) was less biodegradable. Ni-chelates were the most recalcitrant against biodegradation. The study shows that even a moderate input of chelates to soil increases the solubility of toxic heavy metals and their risk of leaching. - When correcting Fe chlorosis Fe-EDDS causes lower environmental concern than Fe-EDTA.

  10. Effects of iron(III)chelates on the solubility of heavy metals in calcareous soils.

    Science.gov (United States)

    Ylivainio, Kari

    2010-10-01

    In this study I evaluated the effects of complexing agents on the solubility of heavy metals in an incubation experiment up to 56 days when complexing agents were applied as Fe-chelates (Fe-EDDS(S,S), Fe-EDDS(mix), Fe-EDTA and Fe-EDDHA) on calcareous soils at a level sufficient to correct Fe chlorosis (0.1 mmol kg(-1)). Of these ligands, EDDHA was the most efficient in keeping Fe in water-soluble form, and EDDS increased the solubility of Cu and Zn most, and only EDTA increased the solubility of Cd and Pb. EDTA increased the solubility of Ni steadily during the incubation period, equalling about 5-8% of the added EDTA concentration. [S,S]-EDDS was biodegraded within 56 days, whereas EDDS(mix) was less biodegradable. Ni-chelates were the most recalcitrant against biodegradation. The study shows that even a moderate input of chelates to soil increases the solubility of toxic heavy metals and their risk of leaching. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

  11. Inorganic Phosphorus Fractions and Their Relationships with Soil Characteristics of Selected Calcareous Soils of Fars Province

    Directory of Open Access Journals (Sweden)

    abolfazl azadi

    2017-01-01

    Full Text Available Introduction: Phosphorus (P is the second limiting nutrient in soils for crop production after nitrogen. Phosphorus is an essential nutrient in crop production. Determination of forms of soil phosphorus is important in the evaluation of soil phosphorus status. Various sequential P fractionation procedures have been used to identify the forms of P and to determine the distribution of P fractions in soils (Chang and Jackson, 1957, Williams et al., 1967; Hedley et al., 1982, but are not particularly sensitive to the various P compounds that may exist in calcareous soils. A Sequential fractionation scheme has been suggested for calcareous soils by which three types of Ca-phosphates i.e. dicalcium phosphate, octacalcium phosphate, and apatite could be identified (Jiang and Gu, 1989. These types of Ca-phosphates were described as Ca2-P (NaHCO3-extractable P, Ca8-P (NH4AC-extractable P and Ca10-P (apatite type, respectively. In this study, the amount and distribution of soil inorganic phosphorus fractions were examined in 49 soil samples of Fars province according to the method described by Jiang and Gu (1989. Materials and Methods: Based on the previous soil survey maps of Fars province and According to Soil Moisture and Temperature Regime Map of Iran (Banaei, 1998, three regions (abadeh, eghlid and noorabad with different Soil Moisture and Temperature Regimes were selected. The soils were comprised Aridic, xeric, and ustic moisture regimes along with mesic, and hyperthemic temperature regimes. 49 representative samples were selected. The soil samples were air-dried and were passed through a 2-mm sieve before analysis. Particle size distribution was determined by hydrometer method (Gee and Bauder 1996. Also, Cation exchange capacity (CEC; Sumner and Miller 1996, calcium carbonate equivalent (Loeppert and Suarez 1996, organic matter content (Nelson and Sommers 1996, and pH by saturated paste method (Thomas 1996 were determined . Inorganic phosphorus

  12. Structural complexity at and around the Triassic-Jurassic GSSP at Kuhjoch, Northern Calcareous Alps, Austria

    Science.gov (United States)

    Palotai, M.; Pálfy, J.; Sasvári, Á.

    2017-10-01

    One of the key requirements for a Global Stratotype Section and Point (GSSP) is the absence of tectonic disturbance. The GSSP for the Triassic-Jurassic system boundary was recently defined at Kuhjoch, Northern Calcareous Alps, Austria. New field observations in the area of the Triassic-Jurassic boundary GSSP site demonstrate that the overturned, tight, and almost upright Karwendel syncline was formed at semibrittle deformation conditions, confirmed by axial planar foliation. Tight to isoclinal folds at various scales were related to a tectonic transport to the north. Brittle faulting occurred before and after folding as confirmed by tilt tests (the rotation of structural data by the average bedding). Foliation is ubiquitous in the incompetent units, including the Kendlbach Formation at the GSSP. A reverse fault (inferred to be formed as a normal fault before folding) crosscuts the GSSP sections, results in the partial tectonic omission of the Schattwald Beds, and thus makes it impossible to measure a complete and continuous stratigraphic section across the whole Kendlbach Formation. Based on these observations, the Kuhjoch sections do not fulfil the specific requirement for a GSSP regarding the absence of tectonic disturbances near boundary level.

  13. Distributions of carbon in calcareous soils under different land uses in western Iran

    Directory of Open Access Journals (Sweden)

    H. Sepahvand

    2016-10-01

    Full Text Available Concentrations of Natural stable and unstable carbon in ecosystems have been used extensively to help to understand a wide range of soil processes and functions. This study was conducted to explore the effects of land use changes on different carbon fractions (F1, F2, F3 and F4, permanganate oxidizable carbon (POXC, soil organic carbon (SOC and total organic carbon (TOC associated with soils in calcareous soils of western Iran. Four popular land uses in the selected site including natural forest, range land, dryland farming and irrigated farming systems were employed as the basis of soil sampling. The results showed a strong relationship between land use conversion and SOC stocks changes. The greatest mean values for carbon content and the least mean values of CaCO3 in bulk topsoil (0–15 cm in the forest land were observed. Dryland farming had the least both active and passive pools of C in comparison with the other land uses. The positive and significant correlations was observed between SOC, Total C and POXC contents and different C fractions. Taking C and POXC pools into account, a more definitive picture of the soil C is obtained than when only total C is measured. The influence of land use changes on overall soil carbon stocks could be helpful for making management decision for farmers and policy makers in the future, for enhancing the potential of C sequestration in western Iran.

  14. The impact of oscillating redox conditions: Arsenic immobilisation in contaminated calcareous floodplain soils

    International Nuclear Information System (INIS)

    Parsons, Christopher T.; Couture, Raoul-Marie; Omoregie, Enoma O.; Bardelli, Fabrizio; Greneche, Jean-Marc; Roman-Ross, Gabriela; Charlet, Laurent

    2013-01-01

    Arsenic contamination of floodplain soils is extensive and additional fresh arsenic inputs to the pedosphere from human activities are ongoing. We investigate the cumulative effects of repetitive soil redox cycles, which occur naturally during flooding and draining, on a calcareous fluvisol, the native microbial community and arsenic mobility following a simulated contamination event. We show through bioreactor experiments, spectroscopic techniques and modelling that repetitive redox cycling can decrease arsenic mobility during reducing conditions by up to 45%. Phylogenetic and functional analyses of the microbial community indicate that iron cycling is a key driver of observed changes to solution chemistry. We discuss probable mechanisms responsible for the arsenic immobilisation observed in-situ. The proposed mechanisms include, decreased heterotrophic iron reduction due to the depletion of labile particulate organic matter (POM), increases to the proportion of co-precipitated vs. aqueous or sorbed arsenic with α-FeOOH/Fe(OH) 3 and potential precipitation of amorphous ferric arsenate. Highlights: •Oscillating redox conditions and heterotrophic metabolism are implemented in PHREEQC. •Depletion of labile organic matter limits iron reduction and arsenic release. •Amorphous FeAsO 4 ∙2H 2 O precipitation potentially limits arsenic mobility during redox cycling. •Water fluctuating zones may naturally attenuate arsenic liberation during flooding. -- We demonstrate through batch experiments, spectroscopy and modelling that repetitive cycles of oxidation and reduction decrease arsenic mobility in soils during subsequent reducing conditions

  15. Relationships between nutrient composition of flowers and fruit quality in orange trees grown in calcareous soil.

    Science.gov (United States)

    Pestana, Maribela; Beja, Pedro; Correia, Pedro José; de Varennes, Amarilis; Faria, Eugénio Araújo

    2005-06-01

    To determine if flower nutrient composition can be used to predict fruit quality, a field experiment was conducted over three seasons (1996-1999) in a commercial orange orchard (Citrus sinensis (L.) Osbeck cv. 'Valencia Late', budded on Troyer citrange rootstock) established on a calcareous soil in southern Portugal. Flowers were collected from 20 trees during full bloom in April and their nutrient composition determined, and fruits were harvested the following March and their quality evaluated. Patterns of covariation in flower nutrient concentrations and in fruit quality variables were evaluated by principal component analysis. Regression models relating fruit quality variables to flower nutrient composition were developed by stepwise selection procedures. The predictive power of the regression models was evaluated with an independent data set. Nutrient composition of flowers at full bloom could be used to predict the fruit quality variables fresh fruit mass and maturation index in the following year. Magnesium, Ca and Zn concentrations measured in flowers were related to fruit fresh mass estimations and N, P, Mg and Fe concentrations were related to fruit maturation index. We also established reference values for the nutrient composition of flowers based on measurements made in trees that produced large (> 76 mm in diameter) fruit.

  16. The use of point load test for Dubai weak calcareous sandstones

    Directory of Open Access Journals (Sweden)

    Amr Farouk Elhakim

    2015-08-01

    Full Text Available Intact rock is typically described according to its uniaxial compressive strength (UCS. The UCS is needed in the design of geotechnical engineering problems including stability of rock slopes and design of shallow and deep foundations resting on and/or in rocks. Accordingly, a correct measurement/evaluation of the UCS is essential to a safe and economic design. Typically, the UCS is measured using the unconfined compression tests performed on cylindrical intact specimens with a minimum length to width ratio of 2. In several cases, especially for weak and very weak rocks, it is not possible to extract intact specimens with the needed minimum dimensions. Thus, alternative tests (e.g. point load test, Schmidt hammer are used to measure rock strength. The UCS is computed based on the results of these tests through empirical correlations. The literature includes a plethora of these correlations that vary widely in estimating rock strength. Thus, it is paramount to validate these correlations to check their suitability for estimating rock strength for a specific location and geology. A review of the available correlations used to estimate the UCS from the point load test results is performed and summarized herein. Results of UCS, point load strength index and Young's modulus are gathered for calcareous sandstone specimens extracted from the Dubai area. A correlation for estimating the UCS from the point load strength index is proposed. Furthermore, the Young's modulus is correlated to the UCS.

  17. Dilatant shear band formation and diagenesis in calcareous, arkosic sandstones, Vienna Basin (Austria)

    Science.gov (United States)

    Lommatzsch, Marco; Exner, Ulrike; Gier, Susanne; Grasemann, Bernhard

    2015-01-01

    The present study examines deformation bands in calcareous arkosic sands. The investigated units can be considered as an equivalent to the Matzen field in the Vienna Basin (Austria), which is one of the most productive oil reservoirs in central Europe. The outcrop exposes carbonate-free and carbonatic sediments of Badenian age separated by a normal fault. Carbonatic sediments in the hanging wall of the normal fault develop dilation bands with minor shear displacements (< 2 mm), whereas carbonate-free sediments in the footwall develop cataclastic shear bands with up to 70 cm displacement. The cataclastic shear bands show a permeability reduction up to 3 orders of magnitude and strong baffling effects in the vadose zone. Carbonatic dilation bands show a permeability reduction of 1-2 orders of magnitude and no baffling structures. We distinguished two types of deformation bands in the carbonatic units, which differ in deformation mechanisms, distribution and composition. Full-cemented bands form as dilation bands with an intense syn-kinematic calcite cementation, whereas the younger loose-cemented bands are dilatant shear bands cemented by patchy calcite and clay minerals. All analyzed bands are characterized by a porosity and permeability reduction caused by grain fracturing and cementation. The changed petrophysical properties and especially the porosity evolution are closely related to diagenetic processes driven by varying pore fluids in different diagenetic environments. The deformation band evolution and sealing capacity is controlled by the initial host rock composition. PMID:26300577

  18. Bacteria transport and retention in intact calcareous soil columns under saturated flow conditions

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    Farrokhian Firouzi Ahmad

    2015-06-01

    Full Text Available Study of bacterial transport and retention in soil is important for various environmental applications such as groundwater contamination and bioremediation of soil and water. The main objective of this research was to quantitatively assess bacterial transport and deposition under saturated conditions in calcareous soil. A series of leaching experiments was conducted on two undisturbed soil columns. Breakthrough curves of Pseudomonas fluorescens and Cl were measured. After the leaching experiment, spatial distribution of bacteria retention in the soil columns was determined. The HYDRUS-1D one- and two-site kinetic models were used to predict the transport and deposition of bacteria in soil. The results indicated that the two-site model fits the observed data better than one-site kinetic model. Bacteria interaction with the soil of kinetic site 1 revealed relatively fast attachment and slow detachment, whereas attachment to and detachment of bacteria from kinetic site 2 was fast. Fast attachment and slow detachment of site 1 can be attributed to soil calcium carbonate that has favorable attachment sites for bacteria. The detachment rate was less than 0.02 of the attachment rate, indicating irreversible attachment of bacteria. High reduction rate of bacteria was also attributed to soil calcium carbonate.

  19. The effects of ozone and NOx on the deterioration of calcareous stone

    International Nuclear Information System (INIS)

    Massey, S.W.

    1999-01-01

    This paper looks at the changes in urban air quality and the effect on building materials with particular regard to their deterioration arising from pollution due to vehicles. The paper aims to review basic information on the likely effect of NO x and ozone on calcareous building materials (limestone, marble, dolomite, calcareous cemented sandstone) by examining experimental and fieldwork relating to the principle reaction of the oxidation of the sulphite to sulphate. NO 2 is only one of many possible oxidants present in the urban and rural environment. A brief synopsis of the effects of other oxidants and inhibitors is given along with a review of the processes involved in aqueous phase oxidation, which seems to be the phase where the reactions take place. Controlling factors in the reaction and oxidation of sulphite to sulphate are the type and porosity of the stone, the level of humidity, the nature of the oxidants and to a lesser extent the presence of other extraneous reactants, e.g. metal oxides, chlorine and ammonia salts. For freshly cut stone unpolished marble is much less reactive than porous limestone and the degree of activity has different relative humidity thresholds. Reaction of the stone with the gaseous compounds occurs during the process of absorption onto the surface. The oxidation is accelerated at the gas-water interface by the presence of NO x , and seems to depend on the NO 2 component but it is clear that NO x is only one of many possible oxidants in the urban and rural environments. Correlation studies of the damage to stone materials are unlikely to pick up the effects of NO x due to the nature of their duration and the rather transient nature of the appearance and removal of nitrates on the stone. Presence of other oxidants and catalysts such as H 2 O 2 , O 2 (catalysed by Fe 3+ and Mn 2+ ), OH, HSO 5 - , SO 4 2- , O 3 , HO 2 , NO 2 - , NO 3 , O 2 - and PAN, plus the fact that the reactions are pH and ionic strength sensitive, add greatly

  20. The effects of ozone and NO{sub x} on the deterioration of calcareous stone

    Energy Technology Data Exchange (ETDEWEB)

    Massey, S.W. [Building Research Establishment Ltd, Garston, Watford (United Kingdom)

    1999-03-09

    This paper looks at the changes in urban air quality and the effect on building materials with particular regard to their deterioration arising from pollution due to vehicles. The paper aims to review basic information on the likely effect of NO{sub x} and ozone on calcareous building materials (limestone, marble, dolomite, calcareous cemented sandstone) by examining experimental and fieldwork relating to the principle reaction of the oxidation of the sulphite to sulphate. NO{sub 2} is only one of many possible oxidants present in the urban and rural environment. A brief synopsis of the effects of other oxidants and inhibitors is given along with a review of the processes involved in aqueous phase oxidation, which seems to be the phase where the reactions take place. Controlling factors in the reaction and oxidation of sulphite to sulphate are the type and porosity of the stone, the level of humidity, the nature of the oxidants and to a lesser extent the presence of other extraneous reactants, e.g. metal oxides, chlorine and ammonia salts. For freshly cut stone unpolished marble is much less reactive than porous limestone and the degree of activity has different relative humidity thresholds. Reaction of the stone with the gaseous compounds occurs during the process of absorption onto the surface. The oxidation is accelerated at the gas-water interface by the presence of NO{sub x}, and seems to depend on the NO{sub 2} component but it is clear that NO{sub x} is only one of many possible oxidants in the urban and rural environments. Correlation studies of the damage to stone materials are unlikely to pick up the effects of NO{sub x} due to the nature of their duration and the rather transient nature of the appearance and removal of nitrates on the stone. Presence of other oxidants and catalysts such as H{sub 2}O{sub 2}, O{sub 2} (catalysed by Fe{sup 3+} and Mn{sup 2+}), OH, HSO{sub 5}{sup -}, SO{sub 4}{sup 2-}, O{sub 3}, HO{sub 2}, NO{sub 2}{sup -}, NO{sub 3}, O

  1. The effects of ozone and NO{sub x} on the deterioration of calcareous stone

    Energy Technology Data Exchange (ETDEWEB)

    Massey, S.W. [Building Research Establishment Ltd., Garston, Watford (United Kingdom)

    1999-03-09

    This paper looks at the changes in urban air quality and the effect on building materials with particular regard to their deterioration arising from pollution due to vehicles. The paper aims to review basic information on the likely effect of NO{sub x} and ozone on calcareous building materials (limestone, marble, dolomite, calcareous cemented sandstone) by examining experimental and fieldwork relating to the principle reaction of the oxidation of the sulphite to sulphate. NO{sub 2} is only one of many possible oxidants present in the urban and rural environment. A brief synopsis of the effects of other oxidants and inhibitors is given along with a review of the processes involved in aqueous phase oxidation, which seems to be the phase where the reactions take place. Controlling factors in the reaction and oxidation of sulphite to sulphate are the type and porosity of the stone, the level of humidity, the nature of the oxidants and to a lesser extent the presence of other extraneous reactants, e.g. metal oxides, chlorine and ammonia salts. For freshly cut stone unpolished marble is much less reactive than porous limestone and the degree of activity has different relative humidity thresholds. Reaction of the stone with the gaseous compounds occurs during the process of absorption onto the surface. The oxidation is accelerated at the gas-water interface by the presence of NO{sub x}, and seems to depend on the NO{sub 2} component but it is clear that NO{sub x} is only one of many possible oxidants in the urban and rural environments. Correlation studies of the damage to stone materials are unlikely to pick up the effects of NO{sub x} due to the nature of their duration and the rather transient nature of the appearance and removal of nitrates on the stone. Presence of other oxidants and catalysts such as H{sub 2}O{sub 2}, O{sub 2} (catalysed by Fe{sup 3+} and Mn{sup 2+}), OH, HSO{sub 5}{sup -}, SO{sub 4}{sup 2-}, O{sub 3}, HO{sub 2}, NO{sub 2}{sup -}, NO{sub 3}, O

  2. Spatial Variability and Geostatistical Prediction of Some Soil Hydraulic Coefficients of a Calcareous Soil

    Directory of Open Access Journals (Sweden)

    Ali Akbar Moosavi

    2017-02-01

    Full Text Available Introduction: Saturated hydraulic conductivity and the other hydraulic properties of soils are essential vital soil attributes that play role in the modeling of hydrological phenomena, designing irrigation-drainage systems, transportation of salts and chemical and biological pollutants within the soil. Measurement of these hydraulic properties needs some special instruments, expert technician, and are time consuming and expensive and due to their high temporal and spatial variability, a large number of measurements are needed. Nowadays, prediction of these attributes using the readily available soil data using pedotransfer functions or using the limited measurement with applying the geostatistical approaches has been receiving high attention. The study aimed to determine the spatial variability and prediction of saturated (Ks and near saturated (Kfs hydraulic conductivity, the power of Gardner equation (α, sorptivity (S, hydraulic diffusivity (D and matric flux potential (Фm of a calcareous soil. Material and Methods: The study was carried out on the soil series of Daneshkadeh located in the Bajgah Agricultural Experimental Station of Agricultural College, Shiraz University, Shiraz, Iran (1852 m above the mean sea level. This soil series with about 745 ha is a deep yellowish brow calcareous soil with textural classes of loam to clay. In the studied soil series 50 sampling locations with the sampling distances of 16, 8 , and 4 m were selected on the relatively regular sampling design. The saturated hydraulic conductivity (Ks, near saturated hydraulic conductivity (Kfs, the power of Gardner equation (α, sorptivity (S, hydraulic diffusivity (D and matric flux potential (Фm of the aforementioned sampling locations was determined using the Single Ring and Droplet methods. After, initial statistical processing, including a normality test of data, trend and stationary analysis of data, the semivariograms of each studied hydraulic attributes were

  3. Paleoclimate and paleoecology of the mid Cretaceous traced by calcareous nannofossils

    Science.gov (United States)

    Bottini, Cinzia; Erba, Elisabetta

    2016-04-01

    The Aptian - early Turonian time interval was marked by major environmental changes at regional to global scale. Specifically, it was a time of super-greenhouse conditions and the climate-ocean system experienced phases of stability perturbed by transient, sometimes prolonged, anomalies of the global carbon cycle. Several regional to global episodes occurred over this time interval: the early Aptian Oceanic Anoxic Event (OAE) 1a, the early Albian OAE 1b, the latest Albian OAE 1d, the Mid-Cenomanian Event (MCE I) and the Cenomanian - Turonian OAE 2. Decades of multidisciplinary research focused on OAEs since they constitute ideal case-histories for the understanding of our planet functioning during perturbations of the C cycle. They were, in fact, characterized by excess CO2, intense volcanism, and altered climate and oceanic chemistry. A useful tool for reconstructing the marine ecosystem dynamics of the past, is calcareous nannoplankton, since it is extremely sensitive to changes in surface waters parameters like temperature and nutrient content and interacts with the C cycle through biological processes and production of calcareous oozes. Here, we gathered new quantitative nannofossil data for the Tethys Ocean (Umbria Marche Basin, Italy) to derive climatic fluctuations and changes in ocean fertility during the late Albian - early Turonian. Over this time interval, the Tethys Ocean was characterized by phases of rhythmic black shale deposition controlled by orbital forcing. The Pialli Level is the Tethyan sedimentary expression of the latest Albian OAE 1d, characterized by large-scale occurrence of black shales and a δ13C positive excursion recognized in several deep-marine settings. The other prominent δ13C anomaly coincides with the OAE 2 represented, in Italy, by the Bonarelli Level. Between these two main C-isotopic excursions, a double-spiked minor anomaly identifies the MCE I, lithologically represented by a shift to black shales and black chert bands

  4. Phosphorus status and sorption characteristics of some calcareous soils of Hamadan, western Iran

    Science.gov (United States)

    Jalali, Mohsen

    2007-10-01

    Phosphorus (P) application in excess of plant requirement may result in contamination of drinking water and eutrophication of surface water bodies. The phosphorous buffer capacity (PBC) of soil is important in plant nutrition and is an important soil property in the determination of the P release potential of soils. Phosphorus sorption greatly affects both plant nutrition and environmental pollution. For better and accurate P fertilizer recommendations, it is necessary to quantify P sorption. This study was conducted to investigate available P and P sorption by calcareous soils in a semi-arid region of Hamadan, western Iran. The soil samples were mainly from cultivated land. Olsen’s biocarbonate extractable P (Olsen P) varied among soils and ranged from 10 to 80 mg kg-1 with a mean of 36 mg kg-1. Half of the soils had an Olsen P > 40 mg kg-1 and >70% of them had a concentration >20 mg kg-1, whereas the critical concentration for most crops is potato (44 kg kg-1) fields than in dry-land wheat farming (24 mg kg-1), pasture (30 mg kg-1), and wheat (24 mg P kg-1) fields. A marked increase in fertilizer P rates applied to agricultural soils has caused P to be accumulated in the surface soil. Phosphate sorption curves were well fitted to the Freundlich equation. The standard P requirement (SPR) of soils, defined as the amount of P sorbed at an equilibrium concentration of 0.2 mg l-1 ranged from 4 to 102 mg kg-1. Phosphorus buffer capacity was relatively high and varied from 16 to 123 l kg-1 with an average of 58 l kg-1. In areas of intensive crop production, continual P applications as P fertilizer and farmyard manure have been used at levels exceeding crop requirements. Surface soil accumulations of P are high enough that loss of P in surface runoff and a high risk for P transfer into groundwater have become priority management concerns.

  5. Intrinsic Problems In Determination Of Soil Texture In Calcareous Soils Of Arid Zones

    Directory of Open Access Journals (Sweden)

    Mozna A. Ahmed

    2017-08-01

    Full Text Available This study aimed at studying the effect of removal of CaCO3 on the texture of the soil profile and that of the control section in some Aridisols of the Sudan. Sixty soil profiles were sampled from Shendi area latitude1636 and longitude 33 48 River Nile State Sudan. These soils were analyzed for CaCO3 and 20 of these profiles were found to be of relatively appreciable calcareousness and were therefore selected for this study. The following three weighted soil textures were determined 1 before any removal of the CaCO3 Texture1 2 after the removal of CaCO3 Texture2 3 after amending the texture by adding the clay sized CaCO3 to the silt fraction Texture 3. Statistical analysis revealed significant differences among soil separates in the three textures except between clay of T2 and clay of T3 and among sand fractions in the three textures. That was not unexpected because the first texture included both mineral separates plus their equivalent size of CaCO3 the second texture included only the mineral separates in complete absence of CaCO3 while texture 3 was an amended texture. The change in the textural class amounted to 72 of the profiles. Statistical analysis in the weighted texture of the control section revealed that this texture was not affected except in two profiles. That could be attributed to the fact that the clay content of the soils of the study area did not fall at or near the boundary between any two major textural classes used in the Soil Taxonomy. The size of the CaCO3 was found in the order of clay size silt size sand size.

  6. A neogene seawater sulfur isotope age curve from calcareous pelagic microfossils

    International Nuclear Information System (INIS)

    Burdett, J.W.; Arthur, M.A.; Richardson, M.

    1989-01-01

    Until now, our knowledge of the sulfur isotopic composition of seawater through geologic time has depended on stable isotopic analysis of sulfate from evaporites. Owing to the sporadic occurrence of evaporites through time, the secular sulfur isotope age curve contains many gaps with little or no data. In order to fill in some of these gaps, particularly the Neogene, we have analyzed the sulfur isotopic composition of carbonate-associated sulfate in carbonate tests of planktonic foraminifera. Other investigators have shown that sulfate may occur in biogenic calcites either lattice-bound, as micro-fluid inclusions, in adsorbed phases, or as protein polysaccharides. Whatever the origin, the sulfur isotopic composition of this sulfate appears to be representative of that of the water in which the organism lived, as shown by results on recent calcareous foraminifera and macrofossils. Using this approach for study of Miocene to Recent pelagic marine sediments supplemented by new data for Miocene marine evaporites from the Gulf of Suez, we have found that the δ 34 S of seawater has decreased about 2.5per mille over the past 25 m.y. and that most of the decrease has occurred over the past 5 m.y., paralleling a decrease in the δ 13 C of dissolved oceanic bicarbonate from the same interval. Sedimentary redox models based on isotope records suggest that organic carbon and sulfide burial have both decreased over the past 5 m.y. Alternatively, an increase in weathering rates over the past 5 m.y. would not require a decrease in organic carbon or sulfide burial as long as the isotopic effect of the increased river input exceeds the isotopic effect of the burial of the reduced species. In either case, the net result would be a decrease in atmospheric p O2 . (orig.)

  7. Molecular phylogenetic evaluation of classification and scenarios of character evolution in calcareous sponges (Porifera, Class Calcarea.

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    Oliver Voigt

    Full Text Available Calcareous sponges (Phylum Porifera, Class Calcarea are known to be taxonomically difficult. Previous molecular studies have revealed many discrepancies between classically recognized taxa and the observed relationships at the order, family and genus levels; these inconsistencies question underlying hypotheses regarding the evolution of certain morphological characters. Therefore, we extended the available taxa and character set by sequencing the complete small subunit (SSU rDNA and the almost complete large subunit (LSU rDNA of additional key species and complemented this dataset by substantially increasing the length of available LSU sequences. Phylogenetic analyses provided new hypotheses about the relationships of Calcarea and about the evolution of certain morphological characters. We tested our phylogeny against competing phylogenetic hypotheses presented by previous classification systems. Our data reject the current order-level classification by again finding non-monophyletic Leucosolenida, Clathrinida and Murrayonida. In the subclass Calcinea, we recovered a clade that includes all species with a cortex, which is largely consistent with the previously proposed order Leucettida. Other orders that had been rejected in the current system were not found, but could not be rejected in our tests either. We found several additional families and genera polyphyletic: the families Leucascidae and Leucaltidae and the genus Leucetta in Calcinea, and in Calcaronea the family Amphoriscidae and the genus Ute. Our phylogeny also provided support for the vaguely suspected close relationship of several members of Grantiidae with giantortical diactines to members of Heteropiidae. Similarly, our analyses revealed several unexpected affinities, such as a sister group relationship between Leucettusa (Leucaltidae and Leucettidae and between Leucascandra (Jenkinidae and Sycon carteri (Sycettidae. According to our results, the taxonomy of Calcarea is in

  8. Micronutrient Availability in Relation to Selected Soil Properties and landscape Position in Calcareous Soils of Golpayegan

    Directory of Open Access Journals (Sweden)

    Mojtaba Fathi

    2017-02-01

    Full Text Available Introduction: Variety of soil reactions govern the distribution of metal micronutrients that includes complexation with organic and inorganic ligands, ion exchange, adsorption and desorption processes, precipitation and dissolution of solids and acid-based equilibria. The relative importance of these reactions depends on many factors such as soil physical, chemical, and mineralogical properties and the nature of metal ions. Environmental factors such as climate, physiographic position, and soil development may affect variability of some soil properties and thereby nutrient availability. The present research was conducted to find relationships between Iron, manganese, zinc, and copper availability and some major soil properties, physiographic condition and soil development. Materials and Methods: Golpayegan region is located in northwest of Isfahan province in central Iran. The mean elevation of the studied area is 1790 above sea level. Annual precipitation was about 244mm and mean monthly temperature ranges from -6 in January to 34°C in August. The soils were developed on different physiographic conditions including piedmont plains, alluvial-fan, plateaus, and flood plains belonging to Entisols and Aridisols. Soil samples (0–60 cm were collected from 98 grid points with 2000m distance in the agricultural area of Golpayegan. Particle size distribution, calcium carbonate, organic carbon, available potassium and phosphorus of the soils were measured by SWRI standard methods. Available Zn, Cu, Mn, and Fe were determined by addition of 10 g soil to 20mL 0.005M diethylentriaminepentacetic‏. The solutions were shaken for 2 h at 25°C, centrifuged, filtered, and Fe, Mn, Zn, and Cu concentrations were measured by an atomic absorption spectrophotometer. Results Discussion: Studied soils were developed on calcareous material and about 60% of samples have more than 20% of calcium carbonate. Available Fe ranged from 1.4 to 6.5 mg kg-1 (mean 15.8 mg kg-1

  9. Calcareous nannoplankton assemblages across the Pliocene-Pleistocene transition in the southwestern Indian Ocean, IODP Site U1475

    Science.gov (United States)

    Cares, Z.; Farr, C. L.; LeVay, L.; Tangunan, D.; Brentegani, L.

    2017-12-01

    International Ocean Discovery Program (IODP) Expedition 361 cored six sites along the greater Agulhas Current System to track its intensity through time and to better understand its role in global oceanic circulation and climate. One of the main scientific objectives of this expedition was to determine the dynamics of the Indian-Atlantic Ocean Gateway circulation during Pliocene-Pleistocene climate changes in association with changing wind fields and migrating ocean fronts. The Indian-Atlantic Ocean Gateway contains a pronounced oceanic frontal system, the position of which has the potential to influence global climate on millennial scales. Owing to the physical differences between the frontal zones, this region has complex biogeochemistry, changes in phytoplankton distribution, and variations in primary productivity. Site U1475 was cored on the Agulhas Plateau in the Southwestern Indian Ocean and recovered a complete sequence of calcareous ooze spanning the last 7 Ma. Previous studies at this locality have shown latitudinal migrations of the frontal zones over the past 350 kyr that resulted in prominent millennial shifts in primary production, biological pump efficiency, and microfossil assemblages that coincide with Antarctic climate variability. Here we present initial results comprised of calcareous nannoplankton assemblages in order to test if similar latitudinal frontal migrations occurred during the Pliocene-Pleistocene transition (PPT; 2.7 Ma). The calcareous nannoplankton assemblage shows an abundance increase of taxa associated with cooler water and higher primary production across the PPT interval. In addition to a change in species abudance, the Shannon diversity index drops notably across the transition, which is typical of nannoplankton communities in more productive regions. These data suggest that a long-term change in sea surface temperature and nutrient availability took place across the PPT, potentially linked to the northward migration of

  10. Aspects of land application of sewage solids and gamma-irradiated dried sewage solids on calcareous soils

    International Nuclear Information System (INIS)

    McCaslin, B.D.; O'Connor, G.A.; Sivinski, J.S.

    1980-01-01

    One of the cheapest and generally most convenient methods of disposing of sewage sludge is by land application. The greatest risks of land application are potential contamination of the environment by heavy metals, other toxicants, and pathogens. Irradiation of sewage sludge has been shown to have little or no effect on sludge elements available to plants, and can remove the potential pathogen problem. Work at New Mexico State University has shown that, with little risk, gamma-irradiated sewage sludge can be used to great advantage for crop production, especially on highly calcareous soils low in heavy metals essential for plant growth

  11. Effect of four acidifying materials added to a calcareous soil on the availability of phosphorus to ryegrass

    Energy Technology Data Exchange (ETDEWEB)

    Sen Gupta, M B; Cornfield, A H

    1964-12-01

    Ryegrass was grown in a pot test using a calcareous soil (0.36% calcium carbonate) treated with sulfur, ammonium sulfate, ferrous sulfate, and aluminium sulfate at 0.1% sulfur-equivalent, with potassium nitrate added where necessary, including the control, to equalize nitrogen supply. The sulfur treatment was the only one which significantly increased dry matter yields, total phosphorus uptake and top/root ratios in dry matter yields and total phosphorus. The ammonium sulfate, ferrous sulfate, and aluminium sulfate treatments significantly reduced top/root ratios in dry-matter yields and total phosphorus. 6 references, 1 table.

  12. PRIMARY CEMENTED BIPOLAR HEMIARTHROPLASTY WITH TROCHANTERIC AND CALCAR RECONSTRUCTION IN UNSTABLE INTERTROCHANTERIC FRACTURES IN ELDERLY: A PROSPECTIVE STUDY

    Directory of Open Access Journals (Sweden)

    Pandu Ranga Vital

    2015-09-01

    Full Text Available INTRODUCTION : To avoid the complications and morbidity associated with attempted Osteosynthesis of the so called Unstable inter - trochanteric fractures in the elderly population, Primary Cemented Bipolar hemiarthroplasty been around for over three decades now. But, hardly any emphasis been given over the technical aspects to i mprove the functional outcome. Present study is one such, following reconstructive attempts ( O f primary cemented bipolar hemiarthroplasty with trochanter and calcar reconstruction in the elderly population to reduce the risk of unstable Hemiarthroplasty. MATERIALS AND METHODS: This prospective study included 20 cases of elderly patients with mean age of 73.5 years (Age range 66 to 82 yr who sustained multifragmentary/communited inter - trochanteric femur fracture treated with Primary cemented bipolar hemiar throplasty with trochanteric and calcar reconstruction to emphasize the importance of restoration soft tissue tension to reduce the risk of unstable Hemiarthroplasty. Essential Technical steps include Figure of eight / multiple wire loop technique of recons truction ( with or without K ‘wires of greater trochanter/ abductor mechanism and calcar reconstruction either by wiring Lesser trochanteric fragment and or insertion of cortical piece of bone graft (medially under the collar of the prosthesis harvested f rom head and neck fragment. The patients were followed up at six week, three month, six month and one year postoperatively and assessed using Harris Hip Score (HHS. RESULTS: The mean HHS score was 85 (range 69 to 91 at the end of one year. The main clini cal measures were early post - operative full weight bearing, post - operative complication & functional outcome. The time to full weight bearing, the rate of post - operative complications & functional outcome was significantly better in cemented bipolar arthro plasty group. CONCLUSION: The authors strongly believe that primary cemented bipolar

  13. The impact of wildland fires on calcareous Mediterranean pedosystems (Sardinia, Italy) - An integrated multiple approach.

    Science.gov (United States)

    Capra, Gian Franco; Tidu, Simona; Lovreglio, Raffaella; Certini, Giacomo; Salis, Michele; Bacciu, Valentina; Ganga, Antonio; Filzmoser, Peter

    2018-05-15

    Sardinia (Italy), the second largest island of the Mediterranean Sea, is a fire-prone land. Most Sardinian environments over time were shaped by fire, but some of them are too intrinsically fragile to withstand the currently increasing fire frequency. Calcareous pedoenvironments represent a significant part of Mediterranean areas, and require important efforts to prevent long-lasting degradation from fire. The aim of this study was to assess through an integrated multiple approach the impact of a single and highly severe wildland fire on limestone-derived soils. For this purpose, we selected two recently burned sites, Sant'Antioco and Laconi. Soil was sampled from 80 points on a 100×100m grid - 40 in the burned area and 40 in unburned one - and analyzed for particle size fractions, pH, electrical conductivity, organic carbon, total N, total P, and water repellency (WR). Fire behavior (surface rate of spread (ROS), fireline intensity (FLI), flame length (FL)) was simulated by BehavePlus 5.0.5 software. Comparisons between burned and unburned areas were done through ANOVA as well as deterministic and stochastic interpolation techniques; multiple correlations among parameters were evaluated by principal factor analysis (PFA) and differences/similarities between areas by principal component analysis (PCA). In both sites, fires were characterized by high severity and determined significant changes to some soil properties. The PFA confirmed the key ecological role played by fire in both sites, with the variability of a four-modeled components mainly explained by fire parameters, although the induced changes on soils were mainly site-specific. The PCA revealed the presence of two main "driving factors": slope (in Sant'Antioco), which increased the magnitude of ROS and FLI; and soil properties (in Laconi), which mostly affected FL. In both sites, such factors played a direct role in differentiating fire behavior and sites, while they played an indirect role in determining

  14. Origin and Distribution of Methane Entrapped in Calcareous Alpine Proglacial Soil

    Science.gov (United States)

    Zhu, Biqing; Schroth, Martin H.; Henneberger, Ruth; Kübler, Manuel; Zeyer, Josef

    2017-04-01

    Methane (CH4) is an important greenhouse gas. The atmospheric methane concentration has been increasing in recent years, which is caused by imbalance between sources and sinks. Methane has been recently discovered to be entrapped in calcareous Swiss Alpine proglacial soil. This CH4 can be released upon mechanical impact and acidification. However, the amount, distribution and environmental fate of this entrapped CH4 in proglacial environment remain unknown. The entrapped CH4 in proglacial soil may be of modern or ancient origin. Modern origin includes ongoing or recent microbial CH4 production (methanogenesis) in subglacial or proglacial environments. An ancient origin mainly refers to CH4 produced thermogenically. This soil entrapped CH4 might be a common phenomenon along the entire glacial forefield, or it might only be present at few locations and depth. We present results of studies from two Swiss Alpine Glacier catchments, Wildstrubel Glacier (Canton Valais) and the Griessfirn Glacier (Canton Uri). Our main goals were 1) to assess the origin of CH4 entrapped in various glacial environments (subglacial, proglacial and supraglacial, soil and bedrocks) using geochemical and microbiological evidence; 2) to assess the spatial distribution of entrapped CH4. We performed geochemical analysis (CH4 content, gas wetness ([C1]/[C2-C3] alkane ratio), CH4 stable 13C- and 2H-isotopes, TOC) on subglacial, proglacial, and supraglacial soil samples collected from well-aerated and water-logged locations. Geochemical analysis was also selectively conducted on pore-water samples and on rock samples collected from different geological formations along the catchments. We also performed batch incubations on soil samples collected from subglacial, proglacial water-logged and supraglacial zones. In addition, for the aforementioned three types of samples, we also performed molecular analyses targeting the mcrA gene, which encodes the α-subunit of the enzyme methyl-coenzyme M reductase

  15. Geochemical processes in a calcareous sandstone aquifer during managed aquifer recharge with desalinated seawater

    Science.gov (United States)

    Ganot, Yonatan; Russak, Amos; Siebner, Hagar; Bernstein, Anat; Katz, Yoram; Guttman, Jospeh; Kurtzman, Daniel

    2017-04-01

    In the last three years we monitor Managed Aquifer Recharge (MAR) of post-treated desalinated seawater (PTDES) in an infiltration pond, at the Menashe site that overlies the northern part of the Israeli Coastal Aquifer. The PTDES are stabilized with CaCO3 during post-treatment in the desalination plant and their chemical composition differs from those of any other water recharged to the aquifer and of the natural groundwater. We use suction cups in the unsaturated zone, shallow observation wells within the pond and production wells that encircles the MAR Menashe site, to study the geochemical processes during MAR with PTDES. Ion-enrichment (remineralization) of the recharged water was observed in both unsaturated zone and shallow observation wells samples. Enrichment occurs mainly in the first few meters below the pond surface by ion-exchange processes. Mg2+ enrichment is most prominent due to its deficiency in the PTDES. It is explained by ion-exchange with Ca2+, as the PTDES (enriched with Ca2+) infiltrates through a calcareous-sandstone aquifer with various amount of adsorbed Mg2+ (3-27 meq/kg). Hence, the higher concentration of Ca+2 in the PTDES together with its higher affinity to the sediments promotes the release of Mg2+ ions to the recharged water. Water isotopes analysis of the production wells were used to estimate residence time and mixing with local groundwater. At the end of 2016, it was found that the percentage of PTDES in adjacent down-gradient production wells was around 10%, while more distant or up-gradient wells show no mixing with PTDES. The distinct isotope contrast between the recharged desalinated seawater (δ2H=+11.2±0.2‰) and the local groundwater (δ2H ranged from -22.7 to -16.7‰) is a promising tool to evaluate future mixing processes at the Menshae MAR site. Using the Menashe MAR system for remineralization could be beneficial as a primary or complementary post-treatment technique. However, the sustainability of this process is

  16. Zinc and Copper Release Kinetics in a Calcareous Soil amended with Manure and Vermicompost

    Directory of Open Access Journals (Sweden)

    hamid reza motaghian

    2017-02-01

    Full Text Available Introduction: Use of organic fertilizers such as vermicompost in agricultural soils with low organic matter content is almost considered as a one way for adding nutrients in these soils. However, application of these fertilizers may affect micronutrient release characteristics. Micronutrient release Kinetics in soils especially in amended soils give information about potential of amended soils to release these elements into solution. Although it is important to study kinetics of micronutrient release from soils to identify soil micronutrients buffering capacity, little attention has been paid to micronutrients desorption rate studies especially in amended soils. The rate of release micronutrients from soil solid phase by considering micronutrients as adsorbed ions or in mineral forms is an important parameter in nutrition of plants by microelements and a dynamic factor that regulates its continuous supply to growing plants; nonetheless, little attention has been paid to micronutrients kinetics inrelease studies. Material and Methods: In this study, kinetics of zinc (Zn and copper (Cu were compared in one calcareous soil amended with 0, 0.5, and 1% (w/w of manure and vermicompost in a completely randomized design and then amended and un-amended soils were incubated at field capacity, for 30 days. After incubation period, amended and un-amended soils were air-dried and were prepared to kinetics study. Kinetics of Zn and Cu release were studied by successive extraction with DTPA-TEA solution. Two grams of the amended and un-amended soils, in triplicate, suspended in 20 ml DTPA-TEA solution were equilibrated at 25±10C for 1, 8, 24, 48, 72, 96, 120, 144, 168, 336 and 504 h by shaking for 15 min. before incubation and 15 min. before the suspensions were centrifuged. Seven drops of toluene were added to each 1000 ml of extractant to inhibit microbial activity. Zinc and copper desorption with time was fitted by using different equations (Zero

  17. Assessment of inceptisols soil quality following long-term cropping in a calcareous environment.

    Science.gov (United States)

    Rezapour, Salar; Samadi, A

    2012-03-01

    The combination of morphological, clay mineralogy, physicochemical, and fertilitical properties of inceptisols were compared for monitoring soil quality response following long-term agricultural activities. For this target, fifty-nine paired surface soils belonging to five subgroups of inceptisols from the major sugar beet growing area and the adjoining virgin lands were described, sampled, and analyzed. The soils were alkaline and calcareous as characterized by high pH, ranging from 7.2 to 8, and calcium carbonate equivalent, ranging from 60 to 300 g kg(-1). Following long-term sugar beet cultivation, morphological properties modifications were reflected as weakening of structure, hardening of consistency, and brightening of soil color. Although, the quantity of clay minerals did not significantly change through long-term cropping, some modifications in the XRD pattern of illite and smectite were observed in the cultivated soils compared to the adjoining virgin lands mainly as a result of potassium depletion. Without significant variation, sand content decreased by 4-55% and silt and clay increased by 3-22% and 2-15%, respectively, in the cultivated soils than to that of the virgin lands. Both negative and positive aspects of soil quality were reflected regarding soil chemical and fertilitical properties and the role of negative effects far exceeded the role of positive effects. Typic calcixerepts was known to be more degraded through a significant decrease (P ≤ 0.001) in mean value of soil organic carbon (a drop of 24%), total N (a drop of 23%), available K (a drop of 42%), exchangeable K (a drop of 45%), potassium adsorption ratio and potassium saturation ratio (a drop of 44% and 42%, respectively) and a significant increase (P ≤ 0.001) in EC (a rise of 53%). Soil quality index, calculated based on nine soil properties [coarse fragments, pH, SOC, total N, ESP, exchangeable cations (Ca, Mg, and K), and available phosphorus], indicated that 60% of the all soil

  18. Physical and microbiological properties of alluvial calcareous Çumra province soils (Central Anatolia, Turkey

    Directory of Open Access Journals (Sweden)

    Ahmet Sami Erol

    2015-04-01

    Full Text Available Alluvial calcareous soils in Central Anatolia (Konya province, Çumra district has a heavy granulometric composition (average clay, low organic carbon content (less than 1%, but stable pore space structure and favorable agrophysical properties. Studies of the water regime in drip irrigation confirm favorable hydrological properties of these soils. It is assumed that the favorable structure of the pore space due to vigorous activity a large and diverse soil biota. Four phyla dominate in soil biota, among which predominate Actinobacteria. The higher (Streptomyces, and lower (three species Rhodococcus actinobacteria are predominant in large amounts as a part of this phyla. Large biodiversity at a sufficiently high bacteria richness formed the structure of the microbial community that contribute to the balanced production of specific metabolites, including gases (CO2, N2, which allows the soil to function actively, preventing compaction of the pore space and maintaining optimal density, porosity, hydrologic properties of the studied silty clay soils. m the uppermost soil horizons. Analyses of heavy mineral fraction show presence of metamorphic and igneous minerals which indicate participation of weathering products from other rock types in the nearby area. The types of heavy minerals in soils depend more on composition of parent rocks and geomorphic position than on climate type. Soils from Nova Lovcha show similar composition, but the quantity of goethite and hematite significantly increase in soil from plain. Typical high-metamorphic minerals as andalusite, kyanite and sillimanite present only in Nova Lovcha, while garnet dominates in Petrovo and opaque minerals - in Dobrostan. Red soils, formed on slopes, where erosion prevails over accumulation, contain more illite, smectite and vermiculite-smectite, and very few or no kaolinite, whereas the kaolinite is dominant in soils formed on plain. The mineralogical composition of clays in different

  19. A review of the mathematical models used for simulation of calcareous stone deterioration in historical buildings

    Science.gov (United States)

    Saba, M.; Quiñones-Bolaños, E. E.; Barbosa López, Aida Liliana

    2018-05-01

    Historic buildings and monuments are often composed of carbonate-based stone materials, susceptible to deterioration by the action of acidic substances on its main component, calcite (CaCO3). Today the levels of air pollution that attack heterogeneous structures with a mixture of different materials, usually of complex and articulated geometries, are the main responsible of the damage of calcareous stones. However the mechanisms of degradation of the stone and the factors that affect them cannot be simply specified, due to the sum coupled processes involving physical, chemical and biological changes, associated with capillarity and porosity, on the other hand the management of large number of samples and the cost of characterization analysis, modeling can contemplate a tool for the care and protection of real estate over time. Reason why this work shows a bibliographical review of the mathematical models that aim to describe how the deterioration of the surfaces of these structures varies over time, with particular attention to surface recession of stone, as a function of sets of variables that have been considered determinants in the different cases studied. It has been shown that in the last 30 years the models has had a revealing evolution due to the fact that the phenomenon has been gradually understood, putting in the background variables such as SO2 because of its reduction worldwide, and introducing variables such as HNO3 which has had, on the contrary, increasing values. In addition, it has been shown that linear polynomials, even if they lend themselves well to represent the phenomenon, in the last 10 years have been replaced by equations or systems of differential equations with one or more variables taken into account. Finally, it was revealed the lack of an inclusive model, capable of including all possible deterioration processes, and that time by time can be adapted to different case studies, in different parts of the world and with different

  20. Phytoextraction potential of poplar (Populus alba L. var. pyramidalis Bunge) from calcareous agricultural soils contaminated by cadmium.

    Science.gov (United States)

    Hu, Yahu; Nan, Zhongren; Jin, Cheng; Wang, Ning; Luo, Huanzhang

    2014-01-01

    To investigate the phytoextraction potential of Populus alba L. var. pyramidalis Bunge for cadmium (Cd) contaminated calcareous soils, a concentration gradient experiment and a field sampling experiment (involving poplars of different ages) were conducted. The translocation factors for all experiments and treatments were greater than 1. The bioconcentration factor decreased from 2.37 to 0.25 with increasing soil Cd concentration in the concentration gradient experiment and generally decreased with stand age under field conditions. The Cd concentrations in P. pyramidalis organs decreased in the order of leaves > stems > roots. The shoot biomass production in the concentration gradient experiment was not significantly reduced with soil Cd concentrations up to or slightly over 50 mg kg(-1). The results show that the phytoextraction efficiency of P. pyramidalis depends on both the soil Cd concentration and the tree age. Populus pyramidalis is most suitable for remediation of slightly Cd contaminated calcareous soils through the combined harvest of stems and leaves under actual field conditions.

  1. Improving the relationship between soil characteristics and metal bioavailability by using reactive fractions of soil parameters in calcareous soils.

    Science.gov (United States)

    de Santiago-Martín, Ana; van Oort, Folkert; González, Concepción; Quintana, José R; Lafuente, Antonio L; Lamy, Isabelle

    2015-01-01

    The contribution of the nature instead of the total content of soil parameters relevant to metal bioavailability in lettuce was tested using a series of low-polluted Mediterranean agricultural calcareous soils offering natural gradients in the content and composition of carbonate, organic, and oxide fractions. Two datasets were compared by canonical ordination based on redundancy analysis: total concentrations (TC dataset) of main soil parameters (constituents, phases, or elements) involved in metal retention and bioavailability; and chemically defined reactive fractions of these parameters (RF dataset). The metal bioavailability patterns were satisfactorily explained only when the RF dataset was used, and the results showed that the proportion of crystalline Fe oxides, dissolved organic C, diethylene-triamine-pentaacetic acid (DTPA)-extractable Cu and Zn, and a labile organic pool accounted for 76% of the variance. In addition, 2 multipollution scenarios by metal spiking were tested that showed better relationships with the RF dataset than with the TC dataset (up to 17% more) and new reactive fractions involved. For Mediterranean calcareous soils, the use of reactive pools of soil parameters rather than their total contents improved the relationships between soil constituents and metal bioavailability. Such pool determinations should be systematically included in studies dealing with bioavailability or risk assessment. © 2014 SETAC.

  2. Stable isotopic information on calcareous pelitic rocks in the Tizapa volcanogenic massive sulfide deposit area, the United Mexican States

    International Nuclear Information System (INIS)

    Morozumi, Haruhisa; Metsugi, Hideya; Kita, Yoshiyuki; Suzuki, Toru

    1999-01-01

    Tizapa volcanogenic massive sulfide (VMS) deposit is hosted in greenschist facies metamorphic rocks; footwall is green schist of felsic to mafic metavolcanic rocks and hanging wall is graphite schist of metasedimentary pelitic rock. Pb-Pb dating of ore samples indicates 103.4Ma to 156.3Ma for the age of mineralization (JICA/MMAJ, 1991). Hanging wall graphite schist is partially calcareous and overlaid by upper formations consisting of calcareous shake and limestone. δ 13 C(per mille) PDB values were measured for carbonate and organic material in the graphite schist, and δ 18 O(per mille) SMOW values were also measured for same carbonate. Although carbonate and organic material were affected by the metamorphism after mineralization, δ 18 O of carbonate decreases from +22.1 per mille to +17.9 per mille, δ 13 C of carbonate decreases from +0.8 per mille to -4.3 per mille and δ 13 C of organic material decreases from -10.0 per mille to -15.6 per mille with the decrease of vertical distances to ore deposit from 54.20 m to 10.28 m. This phenomenon might indicate the change of sedimentary environment of the reduced condition where the sulfides were precipitated, with the change of temperature. If this assumption is adequate, the method applied in this study is useful for semi-quantitative evaluation to distinguish the favorable condition for the precipitation of sulfides of VMS. (author)

  3. Evidence of compositional and ultrastructural shifts during the development of calcareous tubes in the biofouling tubeworm, Hydroides elegans.

    Science.gov (United States)

    Chan, Vera Bin San; Vinn, Olev; Li, Chaoyi; Lu, Xingwen; Kudryavtsev, Anatoliy B; Schopf, J William; Shih, Kaimin; Zhang, Tong; Thiyagarajan, Vengatesen

    2015-03-01

    The serpulid tubeworm, Hydroides elegans, is an ecologically and economically important species whose biology has been fairly well studied, especially in the context of larval development and settlement on man-made objects (biofouling). Nevertheless, ontogenetic changes associated with calcareous tube composition and structures have not yet been studied. Here, the ultrastructure and composition of the calcareous tubes built by H. elegans was examined in the three early calcifying juvenile stages and in the adult using XRD, FTIR, ICP-OES, SEM and Raman spectroscopy. Ontogenetic shifts in carbonate mineralogy were observed, for example, juvenile tubes contained more amorphous calcium carbonate and were predominantly aragonitic whereas adult tubes were bimineralic with considerably more calcite. The mineral composition gradually shifted during the tube development as shown by a decrease in Sr/Ca and an increase of Mg/Ca ratios with the tubeworm's age. The inner tube layer contained calcite, whereas the outer layer contained aragonite. Similarly, the tube complexity in terms of ultrastructure was associated with development. The sequential appearance of unoriented ultrastructures followed by oriented ultrastructures may reflect the evolutionary history of serpulid tube biominerals. As aragonitic structures are more susceptible to dissolution under ocean acidification (OA) conditions but are more difficult to be removed by anti-fouling treatments, the early developmental stages of the tubeworms may be vulnerable to OA but act as the important target for biofouling control. Copyright © 2015 Elsevier Inc. All rights reserved.

  4. Phosphate solubilization and promotion of maize growth in a calcareous soil by penicillium oxalicum P4 and aspergillus niger P85

    Science.gov (United States)

    Alternative tactics for improving phosphorus nutrition in crop production are needed in China and elsewhere as the over-application of phosphatic fertilizers can adversely impact agricultural sustainability. Penicillium oxalicum P4 and Aspergillus niger P85 were isolated from a calcareous soil in C...

  5. Two fern species new to New Hampshire, with comments on the generation of calcareous-like habitat by base-poor rocks

    Science.gov (United States)

    Scott W. Bailey

    2013-01-01

    Incidental to other field investigations, I happened upon small populations of two fern species not previously reported from New Hampshire: Pellaea atropurpurea (L.) Link and Dryopteris filix-mas (L.) Schott. Both species are typically associated with calcareous habitats, although limestone and marble are nearly absent from New...

  6. Efficacy of Fe(o,o-EDDHA) and Fe(o,p-EDDHA) isomers in supplying Fe to strategy I plants differs in nutrient solution and calcareous soil.

    Science.gov (United States)

    Rojas, Carmen L; Romera, Francisco J; Alcántara, Esteban; Pérez-Vicente, Rafael; Sariego, Cristina; Garcaí-Alonso, J Ignacio; Boned, Javier; Marti, Gabriel

    2008-11-26

    The FeEDDHA [iron(3+) ethylenediamine di(o-hydroxyphenylacetic) acid] is one of the most efficient iron chelates employed in the correction of iron clorosis in calcareous soils. FeEDDHA presents different positional isomers: the ortho-ortho (o,o), the ortho-para (o,p), and the para-para (p,p). Of these isomers, the p,p cannot chelate Fe in soil solution in a wide range of pH values, while both o,o and o,p can. The objective of this work was to compare the efficiency of both isomers (o,o and o,p) to provide Fe to two Strategy I plants (tomato and peach) in nutrient solution (pH approximately 6.0), as well as in calcareous soil (pH approximately 8.4; CALCIXEREPT). For this, chelates of both o,o-EDDHA and o,p-EDDHA with 57Fe (a nonradioactive isotope of Fe) were used, where the 57Fe acts as a tracer. The results obtained showed that the o,o isomer is capable of providing sufficient Fe to plants in both nutrient solution and calcareous soil. However, the o,p isomer is capable of providing sufficient Fe to plants in nutrient solution but not in calcareous soil.

  7. Carboniferous calcareous algae and their associations in the San Emiliano and Lois-Ciguera Formations (Prov. León, NW Spain)

    NARCIS (Netherlands)

    Rácz, L.

    1965-01-01

    This study of the calcareous algae in the limestone deposits of the two formations (San Emiliano and Lois-Ciguera) in NW Spain is based on field observations and microscopical study. It was possible in the field to divide almost all the limestone members into smaller units on the basis of physical,

  8. Astronomical calibration of upper Campanian–Maastrichtian carbon isotope events and calcareous plankton biostratigraphy in the Indian Ocean (ODP Hole 762C)

    DEFF Research Database (Denmark)

    Thibault, Nicolas Rudolph; Husson, Dorothée; Harlou, Rikke

    2012-01-01

    An integrated framework of magnetostratigraphy, calcareous microfossil bio-events, cyclostratigraphy and d13C stratigraphy is established for the upper Campanian–Maastrichtian of ODP Hole 762C (Exmouth Plateau, Northwestern Australian margin). Bulk-carbonate d13C events and nannofossil bio-events...

  9. Calcareous nannofossils of the Jurassic/Cretaceous boundary strata in the Puerto Escaňo section (southern Spain) - biostratigraphy and palaeoecology

    Czech Academy of Sciences Publication Activity Database

    Svobodová, Andrea; Košťák, M.

    2016-01-01

    Roč. 67, č. 3 (2016), s. 223-238 ISSN 1335-0552 Institutional support: RVO:67985831 Keywords : Jurasic/Cretaceous boundary * southern Spain * Tethys * biostratigraphy * calcareous nannofossils * palaeoecology Subject RIV: DB - Geology ; Mineralogy Impact factor: 1.358, year: 2016

  10. New biostratigraphic evidence (texanitid ammonites, inoceramids and calcareous nannofossils) for the Upper and the uppermost Coniacian in the Bohemian Cretaceous Basin

    Czech Academy of Sciences Publication Activity Database

    Svobodová, Andrea; Košťák, M.; Čech, S.; Švábenická, L.

    2014-01-01

    Roč. 165, č. 4 (2014), s. 577-589 ISSN 1860-1804 Institutional support: RVO:67985831 Keywords : Bohemian Cretaceous Basin * Upper Coniacian * biostratigraphy * ammonites * inoceramids * calcareous nannofossils Subject RIV: DB - Geology ; Mineralogy Impact factor: 0.569, year: 2014

  11. Overview of the Plio-Pleistocene geology of Rhodes, Greece. Lithology, calcareous nannofossil biostratigraphy, and sampling of the Kallithea Bay section

    DEFF Research Database (Denmark)

    Thomsen, Erik; Rasmussen, Tine Lander; Hastrup, Annette

    2005-01-01

    -water deposits are assigned to the Lindos Bay clay. Calcareous nannofossil biostratigraphy shows that the age of the marine sequence is early Pleistocene. The brackish water sediments are difficult to date, but they are probably of late Pliocene age. Sixty-nine samples representing all environments were...

  12. Dynamics of phosphorus fractions in the rhizosphere of fababean (Phaseolus vulgaris L.) and maize (Zea mays L.) grown in calcareous and acid soils

    NARCIS (Netherlands)

    Li, G.; Li, Haigang; Leffelaar, P.A.; Shen, J.; Zhang, F.

    2015-01-01

    The dynamics of soil phosphorus (P) fractions were investigated, in the rhizosphere of fababean (Vicia faba L.) and maize (Zea mays L.) grown in calcareous and acid soils. Plants were grown in a mini-rhizotron with a thin (3 mm) soil layer, which was in contact with the root-mat, and considered as

  13. Evolution of the soil humus status on the calcareous Neogene clay dumps of the Sokolov quarry complex in the Czech Republic

    Czech Academy of Sciences Publication Activity Database

    Abakumov, E.V.; Frouz, Jan

    2009-01-01

    Roč. 42, č. 7 (2009), s. 718-724 ISSN 1064-2293 Grant - others:Russian Foundation for Basic Research(XE) 08-04-01128 Institutional research plan: CEZ:AV0Z60660521 Keywords : soil humus status * calcareous Neogene clay dumps * Sokolov quarry complex Subject RIV: EH - Ecology, Behaviour Impact factor: 0.222, year: 2009

  14. Calcareous nannofossils and sedimentary facies in the Upper Cretaceous Bozeş Formation (Southern Apuseni Mountains, Romania

    Directory of Open Access Journals (Sweden)

    Ramona Balc

    2012-02-01

    Full Text Available The lithology, sedimentology and biostratigraphy of the Bozes Formation, which crop out in the SE Metaliferi Mountains (Apuseni Mts. have been investigated in order to establish the age of the deposits and the depositional environment. The sedimentary structures and facies are interpreted as indicating a deep-water depositional environment, representing part of a submarine fan lobe. Three facies assemblages have been identified and described. Calcareous nannofossils were used to determine the age of the investigated deposits. The presence of Lucianorhabdus cayeuxii and Calculites obscurus indicates the CC17 biozone, while UC13 Zone is pointed out by the continuous occurrence of Arkhangelskiella cymbiformis and the absence of Broinsonia parca parca. Thus, the age of the studied deposits is Late Santonian -?Early Campanian.

  15. Predicting the yield and quality of winter wheat grown on calcareous chernozem in the lower Don Region

    Directory of Open Access Journals (Sweden)

    Olga Biryukova

    2015-07-01

    Full Text Available Long-term studies have revealed a system of indicators for predicting the yield of winter wheat grown on a calcareous chernozem. It has been established that the prediction and integrated assessment of the yield and quality of grain should be performed with consideration for the balance of macro- and micronutrients in the grain and the above-ground biomass of plants. It has been shown that the contents of protein and gluten in winter wheat grain are mainly determined by the supply of plants with nitrogen and its balance with Mn, Р, Fe, Zn, and K. Possibility of predicting the contents of macro- and micronutrients in wheat grain from the chemical composition of plants at the shooting stage has been revealed.

  16. Pore Size Distribution Influence on Suction Properties of Calcareous Stones in Cultural Heritage: Experimental Data and Model Predictions

    Directory of Open Access Journals (Sweden)

    Giorgio Pia

    2016-01-01

    Full Text Available Water sorptivity symbolises an important property associated with the preservation of porous construction materials. The water movement into the microstructure is responsible for deterioration of different types of materials and consequently for the indoor comfort worsening. In this context, experimental sorptivity tests are incompatible, because they require large quantities of materials in order to statistically validate the results. Owing to these reasons, the development of analytical procedure for indirect sorptivity valuation from MIP data would be highly beneficial. In this work, an Intermingled Fractal Units’ model has been proposed to evaluate sorptivity coefficient of calcareous stones, mostly used in historical buildings of Cagliari, Sardinia. The results are compared with experimental data as well as with other two models found in the literature. IFU model better fits experimental data than the other two models, and it represents an important tool for estimating service life of porous building materials.

  17. Grazing damage to plants and gastropod and grasshopper densities in a CO 2-enrichment experiment on calcareous grassland

    Science.gov (United States)

    Ledergerber, Stephan; Thommen, G. Heinrich; Baur, Bruno

    Plant-herbivore interactions may change as atmospheric CO 2 concentrations continue to rise. We examined the effects of elevated atmospheric CO 2 and CO 2-exposure chambers on the grazing damage to plants, and on the abundances of potential herbivores (terrestrial gastropods and grasshoppers) in a calcareous grassland in the Jura mountains of Switzerland (village of Nenzlingen). Individuals of most plant species examined showed slight grazing damage. However, plots with CO 2 enrichment and plots with ambient atmosphere did not differ in the extent of grazing damage. Similarly, plots with CO 2 enrichment and plots with ambient atmosphere did not differ in either gastropod or grasshopper density. Experimental plots with and without chambers did not differ in the number of gastropods. However, the densities of gastropods and grasshoppers and extent of grazing damage to plants were generally lower in the experimental area than in the grassland outside the experimental field.

  18. Methodology for the elaboration of Natura 2000 sites designation acts in the Walloon Region (Belgium: calcareous grasslands in the Lesse-and-Lomme area

    Directory of Open Access Journals (Sweden)

    Mahy G.

    2005-01-01

    Full Text Available In the Walloon Region (Belgium, 239 sites have been selected to be included in the Natura 2000 network. The next step is to write designation acts in order to legally protect these 221,000 ha. In this pilot study, a designation act was elaborated for a Natura 2000 site of 2,569 ha and located in the Lesse-and-Lomme area within the Calestienne region. Although the site includes 40 ha of calcareous grasslands, characterised by an exceptional flora and fauna, this habitat is very threatened by abandonment and fragmentation.The methodology used to elaborate the designation act is presented with respect to calcareous grassland. Firstly, in spring and summer 2003, an accurate map of natural habitats was produced, with every single patch of calcareous grassland being mapped. Information was also collected in order to evaluate conservation status. Based on this information, conservation status was then assessed with respect to three different criteria: (1 integrity of the cortege species, (2 habitat structure and (3 degradations. Thirdly, the site was divided into objective zones according to the different habitats and species of Community interest found in the site. Hence, an objective zone was delineated for calcareous grasslands. This objective zone was then divided in several management units. Finally, at these different spatial levels (site, objective zone, management unit, management measures were suggested. As a result, in the draft designation act, the target is to maintain or restore 230 ha of calcareous grassland, instead of the existing 40 ha. This ambitious target requires large-scale restoration and an efficient grazing scheme. These will need important resources for their successful implementation

  19. Genome-wide analysis of the sox family in the calcareous sponge Sycon ciliatum: multiple genes with unique expression patterns

    Directory of Open Access Journals (Sweden)

    Fortunato Sofia

    2012-07-01

    Full Text Available Abstract Background Sox genes are HMG-domain containing transcription factors with important roles in developmental processes in animals; many of them appear to have conserved functions among eumetazoans. Demosponges have fewer Sox genes than eumetazoans, but their roles remain unclear. The aim of this study is to gain insight into the early evolutionary history of the Sox gene family by identification and expression analysis of Sox genes in the calcareous sponge Sycon ciliatum. Methods Calcaronean Sox related sequences were retrieved by searching recently generated genomic and transcriptome sequence resources and analyzed using variety of phylogenetic methods and identification of conserved motifs. Expression was studied by whole mount in situ hybridization. Results We have identified seven Sox genes and four Sox-related genes in the complete genome of Sycon ciliatum. Phylogenetic and conserved motif analyses showed that five of Sycon Sox genes represent groups B, C, E, and F present in cnidarians and bilaterians. Two additional genes are classified as Sox genes but cannot be assigned to specific subfamilies, and four genes are more similar to Sox genes than to other HMG-containing genes. Thus, the repertoire of Sox genes is larger in this representative of calcareous sponges than in the demosponge Amphimedon queenslandica. It remains unclear whether this is due to the expansion of the gene family in Sycon or a secondary reduction in the Amphimedon genome. In situ hybridization of Sycon Sox genes revealed a variety of expression patterns during embryogenesis and in specific cell types of adult sponges. Conclusions In this study, we describe a large family of Sox genes in Sycon ciliatum with dynamic expression patterns, indicating that Sox genes are regulators in development and cell type determination in sponges, as observed in higher animals. The revealed differences between demosponge and calcisponge Sox genes repertoire highlight the need to

  20. Enhanced phytoextraction: II. Effect of EDTA and citric acid on heavy metal uptake by Helianthus annuus from a calcareous soil.

    Science.gov (United States)

    Lesage, E; Meers, E; Vervaeke, P; Lamsal, S; Hopgood, M; Tack, F M G; Verloo, M G

    2005-01-01

    High biomass producing plant species, such as Helianthus annuus, have potential for removing large amounts of trace metals by harvesting the aboveground biomass if sufficient metal concentrations in their biomass can be achieved However, the low bioavailability of heavy metals in soils and the limited translocation of heavy metals to the shoots by most high biomass producing plant species limit the efficiency of the phytoextraction process. Amendment of a contaminated soil with ethylene diamine tetraacetic acid (EDTA) or citric acid increases soluble heavy metal concentrations, potentially rendering them more available for plant uptake. This article discusses the effects of EDTA and citric acid on the uptake of heavy metals and translocation to aboveground harvestable plant parts in Helianthus annuus. EDTA was included in the research for comparison purposes in our quest for less persistent alternatives, suitable for enhanced phytoextraction. Plants were grown in a calcareous soil moderately contaminated with Cu, Pb, Zn, and Cd and treated with increasing concentrations of EDTA (0.1, 1, 3, 5, 7, and 10 mmol kg(-1) soil) or citric acid (0.01, 0.05, 0.25, 0.442, and 0.5 mol kg(-1) soil). Heavy metal concentrations in harvested shoots increased with EDTA concentration but the actual amount of phytoextracted heavy metals decreased at high EDTA concentrations, due to severe growth depression. Helianthus annuus suffered heavy metal stress due to the significantly increased bioavailable metal fraction in the soil. The rapid mineralization of citric acid and the high buffering capacity of the soil made citric acid inefficient in increasing the phytoextracted amounts of heavy metals. Treatments that did not exceed the buffering capacity of the soil (heavy metal concentrations. Treatments with high concentrations resulted in a dissolution of the carbonates and compaction of the soil. These physicochemical changes caused growth depression of Helianthus annuus. EDTA and citric

  1. Ophiolitic detritus in Kimmeridgian resedimented limestones and its provenance from an eroded obducted ophiolitic nappe stack south of the Northern Calcareous Alps (Austria

    Directory of Open Access Journals (Sweden)

    Gawlick Hans-Jürgen

    2015-12-01

    Full Text Available The causes for the Middle to Late Jurassic tectonic processes in the Northern Calcareous Alps are still controversially discussed. There are several contrasting models for these processes, formerly designated “Jurassic gravitational tectonics”. Whereas in the Dinarides or the Western Carpathians Jurassic ophiolite obduction and a Jurassic mountain building process with nappe thrusting is widely accepted, equivalent processes are still questioned for the Eastern Alps. For the Northern Calcareous Alps, an Early Cretaceous nappe thrusting process is widely favoured instead of a Jurassic one, obviously all other Jurassic features are nearly identical in the Northern Calcareous Alps, the Western Carpathians and the Dinarides. In contrast, the Jurassic basin evolutionary processes, as best documented in the Northern Calcareous Alps, were in recent times adopted to explain the Jurassic tectonic processes in the Carpathians and Dinarides. Whereas in the Western Carpathians Neotethys oceanic material is incorporated in the mélanges and in the Dinarides huge ophiolite nappes are preserved above the Jurassic basin fills and mélanges, Jurassic ophiolites or ophiolitic remains are not clearly documented in the Northern Calcareous Alps. Here we present chrome spinel analyses of ophiolitic detritic material from Kimmeridgian allodapic limestones in the central Northern Calcareous Alps. The Kimmeridgian age is proven by the occurrence of the benthic foraminifera Protopeneroplis striata and Labyrinthina mirabilis, the dasycladalean algae Salpingoporella pygmea, and the alga incertae sedis Pseudolithocodium carpathicum. From the geochemical composition the analysed spinels are pleonastes and show a dominance of Al-chromites (Fe3+–Cr3+–Al3+ diagram. In the Mg/(Mg+ Fe2+ vs. Cr/(Cr+ Al diagram they can be classified as type II ophiolites and in the TiO2 vs. Al2O3 diagram they plot into the SSZ peridotite field. All together this points to a harzburgite

  2. The first marine record of the Bartonian Nummulites and Calcareous nannofossils at the Tihoiyeh section of the Jiroft area (Central Iran)

    Science.gov (United States)

    Hadi, Mehdi; Parandavar, Mohammad; Kiani-Shahvandi, Madineh; Dabaghi Sadr, Fatemeh

    2016-04-01

    The studied shallow marine sediments are situated south and southwest of Jiroft town, 180 km south of Keman, from the Tihoiyeh section (near Tihoiyeh village). These deposits at the top of the section include marly limestones with index Nummulites species such as N. perforatus (De Montfort), N. lyelli (D'Archiac and Haime). According to Schaub's nummulitic time scale (1981) and shallow benthic zonation of Serra-Kiel et al. (1998), this interval referred to Bartonian age and SBZ17 zone, respectively. Also, the calcareous nannofossil study on this interval led to identification of 19 well-preserved species belonging to 11 genera of this plankton group. Based on determined index calcareous nannofossiltaxa such as Reticulofenestra bisecta, Sphenolithus obtusus, Sphenolithus intercalaris, Cribrocentrum erbae and associated species such as Sphenolithus pseudoradians, Reticulofenestra wadeae, Cribrocentrum reticulatum and Blackites spinosus this interval assigned to the CNE15 zone of Agnini et al. (2014) that corresponds to upper part of NP16 and lower part of NP17 zones of Martini (1971). It is resulted that, the detected shallow benthic foraminifera zone, corresponds to the calcareous nannofossil zones both indicating Bartonian age. Keywords: Bartonian, Calcareous nannofossil, Nummulites, Central Iran, Tihoiyeh section. References: Agnini, C., Fornaciari, E., Raffi, I, Rita Catanzariti, R., Palike, H., Backman, J. and Rio, D., 2014. Biozonation and biochronology of Paleogene calcareous nannofossils from low and middle latitudes. Newsletters on Stratigraphy, Vol. 47 (2), Pp. 131-181. Martini, E., 1971. Standard Tertiary and Quaternary calcareous nannoplankton zonation. In: Farinacci, A. (Ed.), Proceedings 2nd International Conference Planktonic Microfossils Roma: Rome (Ed. Tecnosci.), 2, Pp. 739-785. Serra-Kiel, J., Hottinger, L., Caus, E., Drobne, K., Fernandez, C., Jauhri, A.K., Less, G., Pavlovec, R., Pignatti, J., Samso, J.M., Schaub, H., Sirel, E., Strougo, A

  3. What do results of common sequential fractionation and single-step extractions tell us about P binding with Fe and Al compounds in non-calcareous sediments?

    Czech Academy of Sciences Publication Activity Database

    Jan, Jiří; Borovec, Jakub; Kopáček, Jiří; Hejzlar, Josef

    2013-01-01

    Roč. 47, č. 2 (2013), s. 547-557 ISSN 0043-1354 R&D Projects: GA ČR(CZ) GA206/09/1764; GA MZe(CZ) QH81012; GA MZe(CZ) QI102A265 Institutional support: RVO:60077344 Keywords : sequential fractionation * ascorbate and oxalate extration * non-calcareous sediments Subject RIV: DA - Hydrology ; Limnology Impact factor: 5.323, year: 2013

  4. Evaluation of the potential of indigenous calcareous shale for neutralization and removal of arsenic and heavy metals from acid mine drainage in the Taxco mining area, Mexico.

    Science.gov (United States)

    Romero, F M; Núñez, L; Gutiérrez, M E; Armienta, M A; Ceniceros-Gómez, A E

    2011-02-01

    In the Taxco mining area, sulfide mineral oxidation from inactive tailings impoundments and abandoned underground mines has produced acid mine drainage (AMD; pH 2.2-2.9) enriched in dissolved concentrations (mg l⁻¹) sulfate, heavy metals, and arsenic (As): SO₄²⁻ (pH 1470-5454), zinc (Zn; 3.0-859), iron (Fe; pH 5.5-504), copper (Cu; pH 0.7-16.3), cadmium (Cd; pH 0.3-6.7), lead (Pb; pH acid-neutralizing potential of limestone decreases when surfaces of the calcite particles become less reactive as they are progressively coated by metal precipitates. This study constitutes first-stage development of passive-treatment systems for treating AMD in the Taxco mine area using indigenous calcareous shale. This geologic material consists of a mixture of calcite, quartz, muscovite, albite, and montmorillonite. Results of batch leaching test indicate that calcareous shale significantly increased the pH (to values of 6.6-7.4) and decreased heavy metal and As concentrations in treated mine leachates. Calcareous shale had maximum removal efficiency (100%) for As, Pb, Cu, and Fe. The most mobile metals ions were Cd and Zn, and their average percentage removal was 87% and 89%, respectively. In this natural system (calcareous shale), calcite provides a source of alkalinity, whereas the surfaces of quartz and aluminosilicate minerals possibly serve as a preferred locus of deposition for metals, resulting in the neutralizing agent (calcite) beings less rapidly coated with the precipitating metals and therefore able to continue its neutralizing function for a longer time.

  5. Calcareous nannofossil assemblages across the Pliensbachian/Toarcian boundary at the Peniche section (Ponta do Trovão, Lusitanian Basin)

    OpenAIRE

    Mailliot, S.; Elmi, S.; Mattioli, E.; Pittet, B.

    2007-01-01

    The Peniche section has revealed moderately-to-well preserved calcareous nannofossil assemblages across the Pliensbachian/Toarcian boundary. This good record has allowed the proposition of a refined biostratigraphic scheme. The stage boundary, as defined by ammonites, is comprised within the NJ5b C. impontus (NW Europe; BOWN & COOPER, 1998) or the NJT5b L. sigillatus (Mediterranean Tethys; MATTIOLI & ERBA, 1999) nannofossil subzones. Since in the Lusitanian Basin a mixing of N- and S-Te...

  6. Field Evidence of Cadmium Phytoavailability Decreased Effectively by Rape Straw and/or Red Mud with Zinc Sulphate in a Cd-Contaminated Calcareous Soil

    Science.gov (United States)

    Li, Bo; Yang, Junxing; Wei, Dongpu; Chen, Shibao; Li, Jumei; Ma, Yibing

    2014-01-01

    To reduce Cd phytoavailability in calcareous soils, the effects of soil amendments of red mud, rape straw, and corn straw in combination with zinc fertilization on Cd extractability and phytoavailability to spinach, tomato, Chinese cabbage and radish were investigated in a calcareous soil with added Cd at 1.5 mg kg−1. The results showed that water soluble and exchangeable Cd in soils was significantly decreased by the amendments themselves from 26% to 70%, which resulted in marked decrease by approximately from 34% to 77% in Cd concentration in vegetables. The amendments plus Zn fertilization further decreased the Cd concentration in vegetables. Also cruciferous rape straw was more effective than gramineous corn straw. In all treatments, rape straw plus red mud combined with Zn fertilization was most effective in decreasing Cd phytoavailability in soils, and it is potential to be an efficient and cost-effective measure to ensure food safety for vegetable production in mildly Cd-contaminated calcareous soils. PMID:25303439

  7. Applications of some non destructive testing techniques to the characterization of calcareous rocks: ultrasounds, X and gamma-ray radiography, tomography, neutron radiography

    International Nuclear Information System (INIS)

    Sicardy, O.

    1986-02-01

    NUCLEART Laboratory has been developping various techniques of conservation of art objects made of wood or stone. It has, among others, achieved a technique of strengthening porous stone objects, by resin impregnation followed by polymerization under gamma rays. The good conduct of such operations implies the existence of characterization means, before and after treatment of the objects. Two means of rocks characterization have been studied: - ultrasound techniques, - radiography techniques. The first part consists in a general description of the calcareous rocks morphology and a presentation of the studied specimens. The second part deals with the application of ultrasound techniques to rocks. Experimentally, one pays particular attention to the specific aspects of ultrasounds propagation inside materials like porous rocks, and especially diffusion phenomena. Results were interpreted in terms of propagation medium structure. Practical interest for rocks control through such techniques has been underligned. The third part concerns the application of radiographic techniques to calcareous rocks. Experimental work consists in establishing exposure curves for a wide range of energy, and the images quality determination. Through a statistics approach, and using digitalization techniques, one has done an exhaustive study of the radiographic noise. Moreover two techniques close to conventional radiography were explored: neutron radiography and X-ray tomography. Their specificity and interest in the case of calcareous rocks have been shown [fr

  8. The study of mechanical behavior on the interface between calcar-defect femur and restorations by means of finite element analysis

    International Nuclear Information System (INIS)

    Shi, X.H.; Jiang, W.; Chen, H.Z.; Zou, W.; Wang, W.D.; Guo, Z.; Luo, J.M.; Gu, Z.W.; Zhang, X.D.

    2008-01-01

    The mechanical behaviors of calcar-defected femur and restorations under physiological load are the key factors that will greatly influence the success of femur calcar defect repairing, especially the stress distribution on the bone-restoration interface. 3D finite elements analysis (FEA) was used to analyze the mechanical characters on the interfaces between femoral calcar defects and bone cement or HA restorations. Under the load of two times of a human weight (1436.03 N) and with the increase of the defect dimension from 6 mm to 12 mm, the maximal stresses on the surface of restorations are from 7.06 MPa to 11.89 MPa for bone cement and 2.97-9 MPa for HA separately. In this condition, HA restoration will probably be broken on the bone-restoration interface when the defect diameter is beyond 8 mm. Furthermore, under the load of 1.5 times of a human weight, HA restoration would not be safe unless the defect dimension is smaller than 10 mm, because the maximal stress (4.62 MPa) on the restoration is only a little lower than compressive strength of HA, otherwise the bone fixation device should be applied to ensure the safety. It is relatively safe for all restorations under all the tested defect sizes when the load is just the weight of a human body

  9. Calcareous nannofossil and ammonite integrated biostratigraphy across the Jurassic - Cretaceous boundary strata of the Kopanitsa composite section (West Srednogorie Unit, southwest Bulgaria)

    Science.gov (United States)

    Stoykova, Kristalina; Idakieva, Vyara; Ivanov, Marin; Reháková, Daniela

    2018-04-01

    Calcareous nannofossil, calpionellid and ammonite occurrences have been directly constrained across the Jurassic-Cretaceous boundary interval in the section of Kopanitsa, SW Bulgaria. This section reveals a continuous and expanded sedimentary record through the Upper Tithonian and Lower Berriasian, besides an excellent calcareous nannofossil and ammonite record. The topmost part of the NJT 16b and the base of NJT 17a nannofossil Subzones correspond to the ammonite Microcanthum / Transitorius Subzone. The major part of the NJT 17a Subzone equates to the Durangites spp. ammonite Zone, whereas the NJT 17b Subzone correlates to the lower part of the B. jacobi ammonite Zone. The NKT nannofossil Zone approximately corresponds to the upper part of the B. jacobi Zone and the NK-1 nannofossil Zone correlates at least to the lowest part of the T. occitanica Zone. The FOs of Nannoconus globulus minor, N. wintereri, N. kamptneri minor, N. steinmannii minor, N. kamptneri kamptneri and N. steinmannii steinmannii are confirmed as reliable bio-horizons for correlations in the Mediterranean Tethys area. The first occurrence of Nannoconus wintereri is regarded as an almost concomitant event with the first occurrence of Berriasella jacobi. We suggest it could be the most useful nannofossil proxy for approximating the base of the B. jacobi Zone. Rare, but relatively well preserved calpionellids and calcareous dinoflagellates together with microfacies analysis were used additionally for stratigraphical and palaeoenvironmental interpretations. The investigated sediments are typical for the steep slope of a steepened ramp, with accumulation of hemipelagic and gravitational deposits.

  10. Field evidence of cadmium phytoavailability decreased effectively by rape straw and/or red mud with zinc sulphate in a Cd-contaminated calcareous soil.

    Directory of Open Access Journals (Sweden)

    Bo Li

    Full Text Available To reduce Cd phytoavailability in calcareous soils, the effects of soil amendments of red mud, rape straw, and corn straw in combination with zinc fertilization on Cd extractability and phytoavailability to spinach, tomato, Chinese cabbage and radish were investigated in a calcareous soil with added Cd at 1.5 mg kg-1. The results showed that water soluble and exchangeable Cd in soils was significantly decreased by the amendments themselves from 26% to 70%, which resulted in marked decrease by approximately from 34% to 77% in Cd concentration in vegetables. The amendments plus Zn fertilization further decreased the Cd concentration in vegetables. Also cruciferous rape straw was more effective than gramineous corn straw. In all treatments, rape straw plus red mud combined with Zn fertilization was most effective in decreasing Cd phytoavailability in soils, and it is potential to be an efficient and cost-effective measure to ensure food safety for vegetable production in mildly Cd-contaminated calcareous soils.

  11. Calcareous nannofossil and ammonite integrated biostratigraphy across the Jurassic – Cretaceous boundary strata of the Kopanitsa composite section (West Srednogorie Unit, southwest Bulgaria

    Directory of Open Access Journals (Sweden)

    Stoykova Kristalina

    2018-04-01

    Full Text Available Calcareous nannofossil, calpionellid and ammonite occurrences have been directly constrained across the Jurassic–Cretaceous boundary interval in the section of Kopanitsa, SW Bulgaria. This section reveals a continuous and expanded sedimentary record through the Upper Tithonian and Lower Berriasian, besides an excellent calcareous nannofossil and ammonite record. The topmost part of the NJT 16b and the base of NJT 17a nannofossil Subzones correspond to the ammonite Microcanthum / Transitorius Subzone. The major part of the NJT 17a Subzone equates to the Durangites spp. ammonite Zone, whereas the NJT 17b Subzone correlates to the lower part of the B. jacobi ammonite Zone. The NKT nannofossil Zone approximately corresponds to the upper part of the B. jacobi Zone and the NK-1 nannofossil Zone correlates at least to the lowest part of the T. occitanica Zone. The FOs of Nannoconus globulus minor, N. wintereri, N. kamptneri minor, N. steinmannii minor, N. kamptneri kamptneri and N. steinmannii steinmannii are confirmed as reliable bio-horizons for correlations in the Mediterranean Tethys area. The first occurrence of Nannoconus wintereri is regarded as an almost concomitant event with the first occurrence of Berriasella jacobi. We suggest it could be the most useful nannofossil proxy for approximating the base of the B. jacobi Zone. Rare, but relatively well preserved calpionellids and calcareous dinoflagellates together with microfacies analysis were used additionally for stratigraphical and palaeoenvironmental interpretations. The investigated sediments are typical for the steep slope of a steepened ramp, with accumulation of hemipelagic and gravitational deposits.

  12. 14C dating of freshwater carbonate sediments with special reference to calcareous tufas and laminated lake sediments

    International Nuclear Information System (INIS)

    Pazdur, M.F.

    1992-09-01

    The sequence of laminated sediment of the lake Gosciaz, Poland, covers more than 13,000 years and is actually the longest sequence known so far. Besides of reconstructing past environmental changes, this sequence offers an excellent possibility for studying natural C-14 variations and calibrating the C-14 time scale in a range beyond 6,000 years B.P. The floating varve chronology based on previously taken sediment cores which cover a period of 9,682 years, has been improved by this study. Relative water level changes of the lake during the past 11,500 years have been reconstructed by means of C-14 and C-13 measurements carried out on carbonate fractions of the lake sediments. Periodical variations in the width of annual layers were found. The periods identified are 11 years and 22 years (solar cycle), 35 years (Bruckner cycle), and 200 years. The ratio of summer layer width and the total width of the annual layer shows secular changes which correlate with paleotemperature records. The duration of the Younger Dryas period was determined by combining the floating varve chronology with isotope and pollen analyses of the sediment material. A value of 1,500 years was found. The study also included radiocarbon dating of calcareous tufa taken from different study areas. 26 refs, 26 figs, 6 tabs

  13. Growth and carbon fixation rate of calcareous algae cricosphaera carterae. Sekkaiso cricosphaera carterae no zoshoku to tanso kotei sokudo

    Energy Technology Data Exchange (ETDEWEB)

    Seki, M; Furusaki, S [The University of Tokyo, Tokyo (Japan). Faculty of Engineering; Shigematsu, K [Sumitomo Chemical Co. Ltd., Osaka (Japan); Shigeta, K [Kanagawa Prefectural Office, Yokohama (Japan)

    1993-09-10

    Notice has been given on a calcareous alga among micro marine algae that play an important role in carbon circulation, and the representative alga, Cricosphaera carterae was cultured to discuss growth and carbon fixation rate experimentally. It was found that nutrient salt is taken in more actively in the bright period during which no fission occurs, and less actively during the growth stage in the dark period. Dependence of nitrate concentration on specific growth rate was measured with semi-continuous culture and two formulas were formulated. The specific growth rate was 0.53/d at an average nitrogen concentration on the ocean surface of 15 mg/m[sup 3]. The maximum specific growth rate was 0.9/d, and the fixing ratio of inorganic carbon to organic carbon was roughly 0.1. Further, the alga was cultured with CO2 concentration doubled (to 715 ppm), where no large difference was discovered in the growth and the inorganic carbon fixation. From these findings, the carbon fixation amount due to algae on the entire earth was calculated to roughly 4 billion tons per year. 23 refs., 10 figs., 4 tabs.

  14. Biological activity of soddy-calcareous soils and cultural layers in Alanian settlements of the Kislovodsk basin

    Science.gov (United States)

    Chernysheva, E. V.; Kashirskaya, N. N.; Korobov, D. S.; Borisov, A. V.

    2014-09-01

    Microbiological investigations of cultural layers were performed in a settlement of the Alanian culture—Podkumskoe-2 (the 2nd-4th centuries AD). The present-day soddy-calcareous soils (rendzinas) used for different purposes were also studied near this settlement. The most significant changes in the initial characteristics of the soil microbial communities occurred under the residential influence more than 1500 years ago; these changes have been preserved until the present time. In the areas subjected to the anthropogenic impact, the total microbial biomass (the weighted average of 3720 μg C/g soil) was lower than that in the background soil. The minimal values of the microbial biomass were found in the soil of the pasture—2.5 times less than in the background soil. The urease activity of the cultural layer was higher than that of the soils nearby the settlement. Elevated values of the cellulose activity were also recorded only in the cultural layers. The current plowing has led to a significant decrease in the mycelium biomass of the microscopic fungi. In the soil of the fallow, the weighted average value of the fungal hyphae biomass along the profile was twice lower than that in the background soil and cultural layers of the settlement. The pasture first affected the active microbial biomass and, to a lesser extent, the amount of microscopic fungi.

  15. A study on zinc distribution in calcareous soils for cowpea (Vigna Unguiculata L.) and barely ( Hordeum Vulgare L.)

    Science.gov (United States)

    Boroomand, Naser; Maleki, Mohammad Reza

    2010-05-01

    Compared to other cereals, such as wheat and barley cultivars which have low sensitivity to Zn deficiency, cowpea is sensitive to zinc (Zn) deficiency, however it extensively grows even in soils with deficient in Zn. A 8-week greenhouse experiment was conducted to study the response of cowpea and barely to Zn in calcareous soils with different DTPA- Zn. The soil samples were taken from soil surface up to 0.3 m in which their DTPA- Zn ranged from 0.5 to 3.5 mg kg-1. Shoot dry matter, concentration and uptake of Zn were found to be significantly correlated with soil DTPA- Zn in cowpea and barely. Critical deficiency level of Zn in cowpea was 1.3 mg kg-1 in soil and 28.5 mg kg-1 in shoot dry matter, however, to barely symptoms of Zn deficiency was not observed and concentration of Zn was higher than the critical level reported in literatures. Organic carbon (OC), calcium carbonate equivalent (CCE), pH and field capacity soil moisture content(FC) were significantly correlated with plant responses to Zn which were the most influenced characteristics to Zn uptake by plants.

  16. Formation of calcareous nodules in loess-paleosol sequences: Reviews of existing models with a proposed new "per evapotranspiration model"

    Science.gov (United States)

    Li, Yanrong; Zhang, Weiwei; Aydin, Adnan; Deng, Xiaohong

    2018-04-01

    Loess is a product of aeolian deposition during Quaternary glaciation cycles. Loess-paleosol sequences are rich in calcareous nodules (CNs). In the literature, two models are widely cited for the formation of CNs, namely "per descendum" and "per ascendum". However, there has been no direct testing or monitoring to support either of these contradictory models. This paper reviews a large number of multidisciplinary literature to evaluate the consistency, reliability and rationality of these two models. Three main conclusions are drawn: (1) the causative factors (variation of pH value along loess-paleosol sequence, decrease of CO2 partial pressure, and reduction of solvent water) that are used to support the per descendum model do not completely explain the supersaturation of infiltration solution with CaCO3, thereby making this model questionable; (2) the per ascendum model explains the formation of CNs along narrow horizons through upward evaporation; however, it fails to produce sporadic distributions and irregular shapes of nodules on loess slope faces and the frequent appearance of nodules around plant roots. In order to reconcile these deficiencies, we conducted an extensive field survey in various parts of Shanxi province. Based on this new set of observations, it was concluded that the "per ascendum" model can be extended to explain all occurrences of CNs. This extended model is called "per evapotranspiration".

  17. Optimizing Available Phosphorus in Calcareous Soils Fertilized with Diammonium Phosphate and Phosphoric Acid Using Freundlich Adsorption Isotherm

    Science.gov (United States)

    Akhtar, Muhammad

    2013-01-01

    In calcareous soils, phosphorus (P) retention and immobilization take place due to precipitation and adsorption. Since soil pH is considered a major soil variable affecting the P sorption, an acidic P fertilizer could result in low P adsorption compared to alkaline one. Therefore, P adsorption from DAP and phosphoric acid (PA) required to produce desired soil solution P concentration was estimated using Freundlich sorption isotherms. Two soils from Faisalabad and T. T. Singh districts were spiked with 0, 10, and 20 % CaCO3 for 15 days. Freundlich adsorption isotherms (P = aC b/a) were constructed, and theoretical doses of PA and DAP to develop a desired soil solution P level (i.e., 0.20 mg L−1) were calculated. It was observed that P adsorption in soil increased with CaCO3. Moreover, at all the levels of CaCO3, P adsorption from PA was lower compared to that from DAP in both the soils. Consequently, lesser quantity of PA was required to produce desired solution P, 0.2 mg L−1, compared to DAP. However, extrapolating the developed relationship between soil CaCO3 contents and quantity of fertilizer to other similar textured soils needs confirmation. PMID:24307878

  18. Optimizing Available Phosphorus in Calcareous Soils Fertilized with Diammonium Phosphate and Phosphoric Acid Using Freundlich Adsorption Isotherm

    Directory of Open Access Journals (Sweden)

    Asif Naeem

    2013-01-01

    Full Text Available In calcareous soils, phosphorus (P retention and immobilization take place due to precipitation and adsorption. Since soil pH is considered a major soil variable affecting the P sorption, an acidic P fertilizer could result in low P adsorption compared to alkaline one. Therefore, P adsorption from DAP and phosphoric acid (PA required to produce desired soil solution P concentration was estimated using Freundlich sorption isotherms. Two soils from Faisalabad and T. T. Singh districts were spiked with 0, 10, and 20 % for 15 days. Freundlich adsorption isotherms ( were constructed, and theoretical doses of PA and DAP to develop a desired soil solution P level (i.e., 0.20 mg L−1 were calculated. It was observed that P adsorption in soil increased with . Moreover, at all the levels of , P adsorption from PA was lower compared to that from DAP in both the soils. Consequently, lesser quantity of PA was required to produce desired solution P, 0.2 mg L−1, compared to DAP. However, extrapolating the developed relationship between soil contents and quantity of fertilizer to other similar textured soils needs confirmation.

  19. Cation exchange and CaCO 3 dissolution during artificial recharge of effluent to a calcareous sandstone aquifer

    Science.gov (United States)

    Goren, Orly; Gavrieli, Ittai; Burg, Avihu; Lazar, Boaz

    2011-03-01

    SummaryThis research describes a field study and laboratory simulations of the geochemical evolution of groundwater following a recharge of effluent into aquifers. The study was conducted in the soil aquifer treatment (SAT) system of the Shafdan sewage reclamation plant, Israel. The SAT system recharges secondary effluent into the calcareous sandstone sediments of the Israeli Coastal Aquifer as a tertiary treatment. The reclaimed effluent is recovered ca. 500 m off the recharge basin and is used for unlimited irrigation. The laboratory simulations in which effluent was pumped through experimental columns packed with pristine Shafdan sediment showed that the chemical composition of the outflowing water was controlled mainly by cation exchange and CaCO 3 dissolution. Na +, K + and Mg 2+ were adsorbed and Ca 2+ was desorbed during the initial stage of recharge. The equilibrium distribution of the adsorbed cations was: Ca 2+ ˜ 60%, Mg 2+ ˜ 20%, and Na + and K + ˜ 10% each. The Ca 2+ in the Shafdan production wells and in the experimental columns outflow (˜5 meq L -1) was always higher than the Ca 2+ in the recharged effluent (˜3.5 meq L -1), indicating continuous CaCO 3 dissolution. This study demonstrates that besides mixing, a suite of geochemical processes should be considered when assessing groundwater quality following artificial recharge of aquifers.

  20. Linkage between N2O emission and functional gene abundance in an intensively managed calcareous fluvo-aquic soil

    Science.gov (United States)

    Yang, Liuqing; Zhang, Xiaojun; Ju, Xiaotang

    2017-02-01

    The linkage between N2O emissions and the abundance of nitrifier and denitrifier genes is unclear in the intensively managed calcareous fluvo-aquic soils of the North China Plain. We investigated the abundance of bacterial amoA for nitrification and narG, nirS, nirK, and nosZ for denitrification by in situ soil sampling to determine how the abundance of these genes changes instantly during N fertilization events and is related to high N2O emission peaks. We also investigated how long-term incorporated straw and/or manure affect(s) the abundance of these genes based on a seven-year field experiment. The overall results demonstrate that the long-term application of urea-based fertilizer and/or manure significantly enhanced the number of bacterial amoA gene copies leading to high N2O emission peaks after N fertilizer applications. These peaks contributed greatly to the annual N2O emissions in the crop rotation. A significant correlation between annual N2O emissions and narG, nirS, and nirK gene numbers indicates that the abundance of these genes is related to N2O emission under conditions for denitrification, thus partly contributing to the annual N2O emissions. These findings will help to draw up appropriate measures for mitigation of N2O emissions in this ‘hotspot’ region.

  1. Stabilization of Cd-, Pb-, Cu- and Zn-contaminated calcareous agricultural soil using red mud: a field experiment.

    Science.gov (United States)

    Wang, Yangyang; Li, Fangfang; Song, Jian; Xiao, Ruiyang; Luo, Lin; Yang, Zhihui; Chai, Liyuan

    2018-04-12

    Red mud (RM) was used to remediate heavy metal-contaminated soils. Experiments with two different dosages of RM added to soils were carried out in this study. It was found that soil pH increased 0.3 and 0.5 unit with the dosage of 3 and 5% (wt%), respectively. At the dosage of 5%, the highest stabilization efficiencies for Cd, Pb, Cu and Zn reached 67.95, 64.21, 43.73 and 63.73%, respectively. The addition of RM obviously transferred Cd from the exchangeable fraction to the residual fraction. Meanwhile, in comparison with the control (no RM added), it reduced 24.38, 49.20, 19.42 and 8.89% of Cd, Pb, Cu and Zn in wheat grains at the RM addition dosage of 5%, respectively. At the same time, the yield of wheat grains increased 17.81 and 24.66% at the RM addition dosage of 3 and 5%, respectively. Finally, the addition of RM did not change the soil bacterial community. These results indicate that RM has a great potential in stabilizing heavy metals in calcareous agricultural soils.

  2. Effect of phosphorus and zinc on growth and their uptake in hybrid maize grown in a calcareous alluvial soil

    International Nuclear Information System (INIS)

    Parik, B.L.; Santikari, A.K.; Das, S.K.; Chowdhury, B.

    1977-01-01

    Hybrid maize (Zea mays L., var. Ganga 101) was grown in glasshouse at different levels of phosphorus with and without zinc, in a calcareous alluvial soil of North Bihar. Phosphorus was applied at 0, 11, 22, 44 and 88 ppm as tagged P in single superphosphats. Zinc was applied at 0 and 10 ppm as 65 ZnCl 2 . Application of phosphorus and zinc significantly increased the dry matter yield up to P 44 . Higher dose of P resulted in depressed growth accompanied by decreased zinc concentration and uptake by plants, exhibiting zinc deficiency symptoms. Higher levels of P and Zn increased their concentrations in the plant, but their total uptake was reduced at P 88 . With higher levels of P the percent utilization of fertilizer P decreased, while in zinc treated soils uptake of fertilizer P increased. Percent utilization of added zinc increased with increase in P levels upto P 44 and decreased thereafter, although at this level of P a greater percentage of zinc was derived from the fertilizer. (author)

  3. Seasonal calcareous nannoplankton and other biogenic particle fluxes for 1990-2009: twenty-year long records from the central subarctic Pacific Ocean and the Bering Sea

    Science.gov (United States)

    Takahashi, Kozo; Tsutsui, Hideto

    2017-04-01

    Time-series sediment traps were deployed for nearly 20 years (1990-2009) at two long-term locations: Station SA (49°N, 174°W, trap depth 4,800 m, water depth 5,400 m) in the central subarctic Pacific, and Station AB (53.5°N, 177°W, trap depth 3,200 m, water depth 3,800 m) in the southern Bering Sea. Among many biogenic particles, calcareous nannoplankton represented nearly half or more of the entire calcium carbonate fluxes of the regions. Dominant taxa include Coccolithus pelagicus and Emiliania huxleyi. The flux maxima of the former taxon occurred twice a year during June and October-November, whereas that of the latter taxon only occurred primarily once a year in November at both stations, indicating environmental preferences of the taxa. Among many environmental conditions, the fluxes of Emiliania huxleyi showed strong correlations with both water temperatures above 45 m depth and air temperatures (these parameters taken with one-month lag [earlier values] considering sinking time of ca. a month to the respective trap depths). Coccolithus pelagicus, on the other hand, showed lower values in the correlation with temperatures (Tsutsui et al., 2016), indicating that this taxon is somewhat more dependent on other factors such as nutrients compared to those of E. huxleyi. The timings of the seasonal flux maxima of calcareous nannoplankton are quite different from and later than those of other taxonomic groups such as diatoms and silicoflagellates. The primary seasonal flux maxima of diatoms and silicoflagellates, for example, occurred in May, a month earlier than the June maximum of C. pelagicus, and secondary seasonal flux maxima occurred in August, 2-3 months earlier than those of calcareous nannoplankton at both stations, based on 8 year flux records for diatoms (Onodera and Takahashi, 2009) and 4 year records for silicoflagellates (Onodera and Takahashi, 2012). By examining seasonal changes of nitrate and phosphate concentrations above 50 m depth from ERDDAP

  4. Rock physics model of glauconitic greensand from the North Sea

    DEFF Research Database (Denmark)

    Hossain, Zakir; Mukerji, Tapan; Dvorkin, Jack

    2011-01-01

    . Results of rock-physics modeling and thin-section observations indicate that variations in the elastic properties of greensand can be explained by two main diagenetic phases: silica cementation and berthierine cementation. These diagenetic phases dominate the elastic properties of greensand reservoir......-stiff-sand or a stiff-sand model. Berthierine cement has different growth patterns in different parts of the greensand, resulting in a soft-sand model and an intermediate-stiff-sand model. © 2012 Society of Exploration Geophysicists....

  5. Behaviour Of Saline Irrigation Water Components In Pakistani Barley And Calcareous Soil Under Scheduling Irrigation Using Neutron Scattering Technique

    International Nuclear Information System (INIS)

    RIZK, M.A.

    2010-01-01

    This study aims to investigate the behaviour of cation uptake by Pakistani barley (genotype PK-30163) as affected by saline irrigation water, as well as cation distribution within the soil profile. This experiment was carried out at Soil and Water Research Department, Nuclear Research Centre, Atomic Energy Authority, Inshas, Egypt. The soil was transferred from Wadi Sudr (South Sinai, Egypt). It is salted affected soil (calcareous soil, EC = 4.3 dS/m) and was irrigated using ground water irrigation (12.5 dS/m). Nine used lysimeters were irrigated with three artificial saline water (0.3, 4 and 8 dS/m) using drip irrigation system. The irrigation schedule was carried out using neutron scattering technique according to the hydro physical properties of the soil. Pakistani barley (halophytic plant) was used to remove salts from the soil especially sodium cations. The cation uptake and cation distribution (Na, K, Ca, Mg) within the soil profile were studied.The data indicated that roots of barley collected within 0-15 cm layer showed high cation uptake that made the salt concentrations in this layer low. Sodium uptake ratio was 43, 37 and 47% from total cation uptake by using fresh water (0.3 dS/m), 4 and 8 dS/m, respectively. The maximum uptake for Na, K, Ca and Mg was 20.51, 19.13, 3.98 and 12.81 g/lys at 5.69, 3.05, 6.56 and 4.15 dS/m, respectively. It was found that Pakistani barley preferred Mg uptake rather than Ca uptake.

  6. Silicon induced Fe deficiency affects Fe, Mn, Cu and Zn distribution in rice (Oryza sativa L.) growth in calcareous conditions.

    Science.gov (United States)

    Carrasco-Gil, Sandra; Rodríguez-Menéndez, Sara; Fernández, Beatriz; Pereiro, Rosario; de la Fuente, Vicenta; Hernandez-Apaolaza, Lourdes

    2018-04-01

    A protective effect by silicon in the amelioration of iron chlorosis has recently been proved for Strategy 1 species, at acidic pH. However in calcareous conditions, the Si effect on Fe acquisition and distribution is still unknown. In this work, the effect of Si on Fe, Mn, Cu and Zn distribution was studied in rice (Strategy 2 species) under Fe sufficiency and deficiency. Plants (+Si or-Si) were grown initially with Fe, and then Fe was removed from the nutrient solution. The plants were then analysed using a combined approach including LA-ICP-MS images for each element of interest, the analysis of the Fe and Si concentration at different cell layers of root and leaf cross sections by SEM-EDX, and determining the apoplastic Fe, total micronutrient concentration and oxidative stress indexes. A different Si effect was observed depending on plant Fe status. Under Fe sufficiency, Si supply increased Fe root plaque formation, decreasing Fe concentration inside the root and increasing the oxidative stress in the plants. Therefore, Fe acquisition strategies were activated, and Fe translocation rate to the aerial parts was increased, even under an optimal Fe supply. Under Fe deficiency, +Si plants absorbed Fe from the plaque more rapidly than -Si plants, due to the previous activation of Fe deficiency strategies during the growing period (+Fe + Si). Higher Fe plaque formation due to Si supply during the growing period reduced Fe uptake and could activate Fe deficiency strategies in rice, making it more efficient against Fe chlorosis alterations. Silicon influenced Mn and Cu distribution in root. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

  7. Calcareous Nannofossils and Variation of the Kuroshio Current in the Okinawa Tro ugh During the Last 14000 Years

    Directory of Open Access Journals (Sweden)

    Xin

    2005-01-01

    Full Text Available A quantitative census study on calcareous nannofossils from sediments of Site 1202 recovered by ODP Leg 195 and surface sediments from the East China Sea was carried out to obtain a high-resolution nannofossil record of the change of the Kuroshio Current during the late Quaternary. Two nannofossil ratio indices were designed and employed in this study: (1 ratio of Florisphaera profunda against F. profunda, Emiliania huxleyi and Gephyrocapsa oceanica (F-EG ratio as a nannofossil proxy of the Kuroshio Current, (2 ratio of G. oceanica against F. profunda and E. huxleyi and G. oceanica (G-FE ratio as a proxy of near-coast environment. Results from the 14 surface nannofossil samples demonstrate that the F-EG ratio is > 15% in the assemblage lying directly under the main route of the Kuroshio Current, whereas it is very low ( 30% were seen from all samples on the East China Sea continental shelf or from near-coast cores. Down hole nannofossil record from the top 60 mbsf sediment interval at ODP Hole 1202B reflects the change of the Kuroshio Current in the last glacial and postglacial period since 14 ka. Extreme low F-EG ratio together with very high G-FE ratio at Hole 1202B during the time of the latest Pleistocene and the earliest Holocene suggest the absence of the Kuroshio Current in the area studied. The event of intrusion of the Kuroshio Current was clearly recorded by a dramatically increase of F-EG ratio and notably a reduction in the G-FE ratio around 9 ka. Furthermore, based on the variation of the F-EG ratio and _ of planktonic foraminifera Neogloboquadrina dutertrei, variation of the Kuroshio Current in the Holocene shows three long-term cycles (with a periodicity of ~3000 yr.

  8. Effects of zinc complexes on the distribution of zinc in calcareous soil and zinc uptake by maize.

    Science.gov (United States)

    Alvarez, José M; Rico, María I

    2003-09-10

    The movement and availability of Zn from six organic Zn sources in a Typic Xerorthent (calcareous) soil were compared by incubation, column assay, and in a greenhouse study with maize (Zea mays L.). Zinc soil behavior was studied by sequential, diethylenetriaminepentaacetate, and Mehlich-3 extractions. In the incubation experiment, the differences in Zn concentration observed in the water soluble plus exchangeable fraction strongly correlated with Zn uptake by plants in the greenhouse experiment. Zinc applied to the surface of soil columns scarcely moved into deeper layers except for Zn-ethylenediaminetetraacetate (EDTA) that showed the greatest distribution of labile Zn throughout the soil and the highest proportion of leaching of the applied Zn. In the upper part of the column, changes in the chemical forms of all treatments occurred and an increase in organically complexed and amorphous Fe oxide-bound fractions was detected. However, the water soluble plus exchangeable fraction was not detected. The same results were obtained at the end of the greenhouse experiment. Significant increases were found in plant dry matter yield and Zn concentration as compared with the control treatment without Zn addition. Increasing Zn rate in the soil increased dry matter yield in all cases but Zn concentration in the plant increased only with Zn-EDTA and Zn-ethylenediaminedi-o-hydroxyphenyl-acetate (EDDHA) fertilizers. Higher Zn concentration in plants (50.9 mg kg(-)(1)) occurred when 20 mg Zn kg(-)(1) was added to the soil as Zn-EDTA. The relative effectiveness of the different Zn carriers in increasing Zn uptake was in the order: Zn-EDTA > Zn-EDDHA > Zn-heptagluconate >/= Zn-phenolate approximately Zn-polyflavonoid approximately Zn-lignosulfonate.

  9. Ground cover and tree growth on calcareous minesoils: Greater influence of soil surface than nitrogen rate or seed mix

    International Nuclear Information System (INIS)

    Kost, D.A.; Vimmerstedt, J.P.

    1994-01-01

    Growth of ground cover and trees was evaluated for five growing seasons on calcareous coal minesoil surfaces (standard graded topsoil, graded and ripped topsoil, graded gray cast overburden) in southeastern Ohio. Soil surface plots were seeded in September 1987 with either a standard herbaceous seed mix [orchardgrass (Dactylis glomerata L.), timothy (Phleum pratense L.), perennial ryegrass (Lolium perenne L.), Kentucky bluegrass (Poa pratensis L.), Ranger alfalfa (Medicago sativa L.), Mammoth red clover (Trifolium pratense L.), Empire birdsfoot trefoil (Lotus corniculatus L.), and wheat (Triticum aestivum L.)], or a modified mix using no alfalfa and half the rate of orchardgrass. Nitrogen (45, 90, or 135 kg ha/N) was applied as ammonium nitrate in September 1987 and April 1989. White ash (Fraxinus americana L.), silver maple (Acer saccharinum L.), northern red oak (Quercus rubra L.), and eastern white pine (Pinus strobus L.) were planted in spring 1989 into 0.8 m-wide strips sprayed with glyphosate herbicide at 2.24 kg/ha in October 1988. Total cover and total biomass were highest in July 1989, following the last application of nitrogen fertilizer in April 1989. Total cover ranged from 44% to 56%, and total biomass ranged from 102 to 162 g/0.5 m 2 from 1990 to 1993. Total cover and total biomass were lower at the lowest nitrogen rate in 1989 only. Type of herbaceous seed mix did not affect growth of ground cover or trees. Overall tree survival was 82.0% the first year but declined to 40.6% after 5 yr. Survival varied significantly among all tree species (3.5% for pine, 22.2% for oak, 38.5% for maple, 98.1% for ash)

  10. RESPONSE OF SOYBEANS AND WHEAT TO PHOSPHORUS FERTILIZATION ON CALCAREOUS ALLUVIAL SOIL OF SAVA VALLEY AREA IN BOSNIA AND HERZEGOVINA

    Directory of Open Access Journals (Sweden)

    Jurica JOVIC

    2015-08-01

    Full Text Available The stationary field experiment of increasing rates of phosphorus (P fertilization started in spring 2011 on calcareous alluvial soil of Posavian Canton in Federation of Bosnia and Herzegovina (B&H. The level of plant available P was found to be low by previous soil tests carried on with ammonium-lactate-method (7.06 pH in 1 M KCl; 4.17% organic matter; 3.79% CaCO3; 5.4 mg P2O5 in 100 g of soil. Five rates of P fertilizers (monoammonium phosphate: 13% N + 53 % P2O5 were applied as follows (kg P2O5 ha-1: a = 75 (basic fertilization, b = 225, c = 375, d = 525 and e = 975. The experiment was conducted in four replicates (basic plot 60 m2. Only basic fertilization was applied in the following years. Crop rotation was as follows: soybean (2011 - winter wheat (2012 + 2013. Soybean yield increased for 20% (2.11 and 2.53 t ha-1, respectively with P fertilization from 75 to 375 kg P2O5 ha-1, whereas further increase of P rates resulted with lower yield compared to the control level. In both years significant differences of wheat yields were found only between basic and each rate of the increased P fertilization. Wheat yields of the control group were 6.21 and 6.44 t ha-1, for the harvest of 2012 and 2013, respectively. P fertilization led to an increase in wheat yields up to 13% in 2012 and 15% in 2013. Mean values of wheat yields of four P treatments (b+c+d+e were 6.92 and 7.21 t ha-1 for 2012 and 2013, respectively.

  11. Redistribution of fractions of zinc, cadmium, nickel, copper, and lead in contaminated calcareous soils treated with EDTA.

    Science.gov (United States)

    Jalali, Mohsen; Khanlari, Zahra V

    2007-11-01

    Effect of ethylene diamine tetraacetic acid (EDTA) on the fractionation of zinc (Zn), cadmium (Cd), nickel (Ni), copper (Cu), and lead (Pb) in contaminated calcareous soils was investigated. Soil samples containing variable levels of contamination, from 105.9 to 5803 mg/kg Zn, from 2.2 to 1361 mg/kg Cd, from 31 to 64.0 mg/kg Ni, from 24 to 84 mg/kg Cu, and from 109 to 24,850 mg/kg Pb, were subjected to EDTA treatment at different dosages of 0, 1.0, and 2.0 g/kg. Metals in the incubated soils were fractionated after 5 months by a sequential extraction procedure, in which the metal fractions were experimentally defined as exchangeable (EXCH), carbonate (CARB), Mn oxide (MNO), Fe oxide (FEO), organic matter (OM), and residual (RES) fractions. In contaminated soils without EDTA addition, Zn, Ni, Cu, and Pb were predominately present in the RES fraction, up to 60.0%, 32.3%, 41.1%, and 36.8%, respectively. In general, with the EDTA addition, the EXCH and CARB fractions of these metals increased dramatically while the OM fraction decreased. The Zn, Ni, Cu, and Pb were distributed mostly in RES, OM, FEO, and CARB fractions in contaminated soils, but Cd was found predominately in the CARB, MNO, and RES fractions. The OM fraction decreased with increasing amounts of EDTA. In the contaminated soils, EDTA removed some Pb, Zn, Cu, and Ni from MNO, FEO, and OM fractions and redistributed them into CARB and EXCH fractions. Based on the relative percent in the EXCH and CARB fractions, the order of solubility was Cd > Pb > Ni > Cu > Zn for contaminated soils, before adding of EDTA, and after adding of EDTA, the order of solubility was Pb > Cd > Zn > Ni > Cu. The risk of groundwater contamination will increase after applying EDTA and it needed to be used very carefully.

  12. The interplay of stress and mowing disturbance for the intensity and importance of plant interactions in dry calcareous grasslands.

    Science.gov (United States)

    Maalouf, Jean-Paul; Le Bagousse-Pinguet, Yoann; Marchand, Lilian; Touzard, Blaise; Michalet, Richard

    2012-09-01

    There is still debate regarding the direction and strength of plant interactions under intermediate to high levels of stress. Furthermore, little is known on how disturbance may interact with physical stress in unproductive environments, although recent theory and models have shown that this interplay may induce a collapse of plant interactions and diversity. The few studies assessing such questions have considered the intensity of biotic interactions but not their importance, although this latter concept has been shown to be very useful for understanding the role of interactions in plant communities. The objective of this study was to assess the interplay between stress and disturbance for plant interactions in dry calcareous grasslands. A field experiment was set up in the Dordogne, southern France, where the importance and intensity of biotic interactions undergone by four species were measured along a water stress gradient, and with and without mowing disturbance. The importance and intensity of interactions varied in a very similar way along treatments. Under undisturbed conditions, plant interactions switched from competition to neutral with increasing water stress for three of the four species, whereas the fourth species was not subject to any significant biotic interaction along the gradient. Responses to disturbance were more species-specific; for two species, competition disappeared with mowing in the wettest conditions, whereas for the two other species, competition switched to facilitation with mowing. Finally, there were no significant interactions for any species in the disturbed and driest conditions. At very high levels of stress, plant performances become too weak to allow either competition or facilitation and disturbance may accelerate the collapse of interactions in dry conditions. The results suggest that the importance and direction of interactions are more likely to be positively related in stressful environments.

  13. The influence of vegetation structure on spider species richness, diversity and community organization in the Apšuciems calcareous fen, Latvia

    Directory of Open Access Journals (Sweden)

    Štokmane, M.

    2016-07-01

    Full Text Available Calcareous fens are considered to be among the most threatened ecosystems of Europe. They are also one of the most diverse habitats as they support an incredibly rich and diverse range of plant and animal species. However, in spite of their diversity, calcareous fens are still poorly investigated, especially when referring to fen invertebrates, such as spiders. Because spiders are good bioindicators, knowledge of their ecology in rare and threatened habitats is of interest. The aim of this study was to document the composition and diversity of spider species, families and foraging guilds in the ground– and grass–layers of the Apšuciems calcareous fen, and to evaluate the influence of vegetation structure on spider community organization. In summer 2012, we collected ground–dwelling spiders using pitfall traps and grass–dwelling spiders using sweep–netting. A total of 2,937 spider individuals belonging to 19 families and 80 species was collected in the Apšuciems fen. Our results indicate that spider species and families tend to be stratified across the vertical structure of the habitat; the spider composition in the ground stratum differed from that in the grass stratum. On the contrary, however, the spider foraging guild structure between the ground–layer and the grass–layer was similar. Each of the two studied strata presented similar guilds in similar proportions. Our results also showed that spider composition differed considerably between fen parts and that much of this variability could be explained by the architectural properties of the habitat. More diverse vegetation generally supported a higher number of spider species.

  14. Heavy metal accumulation by poplar in calcareous soil with various degrees of multi-metal contamination: implications for phytoextraction and phytostabilization.

    Science.gov (United States)

    Hu, Yahu; Nan, Zhongren; Su, Jieqiong; Wang, Ning

    2013-10-01

    The object of this study was to assess the capacity of Populus alba L. var. pyramidalis Bunge for phytoremediation of heavy metals on calcareous soils contaminated with multiple metals. In a pot culture experiment, a multi-metal-contaminated calcareous soil was mixed at different ratios with an uncontaminated, but otherwise similar soil, to establish a gradient of soil metal contamination levels. In a field experiment, poplars with different stand ages (3, 5, and 7 years) were sampled randomly in a wastewater-irrigated field. The concentrations of cadmium (Cd), Cu, lead (Pb), and zinc (Zn) in the poplar tissues and soil were determined. The accumulation of Cd and Zn was greatest in the leaves of P. pyramidalis, while Cu and Pb mainly accumulated in the roots. In the pot experiment, the highest tissue concentrations of Cd (40.76 mg kg(-1)), Cu (8.21 mg kg(-1)), Pb (41.62 mg kg(-1)), and Zn (696 mg kg(-1)) were all noted in the multi-metal-contaminated soil. Although extremely high levels of Cd and Zn accumulated in the leaves, phytoextraction using P. pyramidalis may take at least 24 and 16 years for Cd and Zn, respectively. The foliar concentrations of Cu and Pb were always within the normal ranges and were never higher than 8 and 5 mg kg(-1), respectively. The field experiment also revealed that the concentrations of all four metals in the bark were significantly higher than that in the wood. In addition, the tissue metal concentrations, together with the NH4NO3-extractable concentrations of metals in the root zone, decreased as the stand age increased. P. pyramidalis is suitable for phytostabilization of calcareous soils contaminated with multiple metals, but collection of the litter fall would be necessary due to the relatively high foliar concentrations of Cd and Zn.

  15. Preoperative digital planning versus postoperative outcomes in total hip arthroplasty using a calcar-guided short stem: frequent valgization can be avoided.

    Science.gov (United States)

    Kutzner, Karl Philipp; Pfeil, Joachim; Kovacevic, Mark Predrag

    2017-07-01

    Modern total hip arthroplasty is largely dependent on the successful preservation of hip geometry. Thus, a successful implementation of the preoperative planning is of great importance. The present study evaluates the accuracy of anatomic hip reconstruction predicted by 2D digital planning using a calcar-guided short stem of the newest generation. A calcar-guided short stem was implanted in 109 patients in combination with a cementless cup using the modified anterolateral approach. Preoperative digital planning was performed including implant size, caput-collum-diaphyseal angle, offset, and leg length using mediCAD II software. A coordinate system and individual scale factors were implemented. Postoperative outcome was evaluated accordingly and was compared to the planning. Intraoperatively used stem sizes were within one unit of the planned stem sizes. The postoperative stem alignment showed a minor and insignificant (p = 0.159) mean valgization of 0.5° (SD 3.79°) compared to the planned caput-collum-diaphyseal angles. Compared to the planning, mean femoral offset gained 2.18 (SD 4.24) mm, while acetabular offset was reduced by 0.78 (SD 4.36) mm during implantation resulting in an increased global offset of 1.40 (SD 5.51) mm (p = 0.0094). Postoperative femoroacetabular height increased by a mean of 5.00 (SD 5.98) mm (p planning in calcar-guided short-stem total hip arthroplasty assures a satisfying implementation of the intended anatomy. Valgization, which has been frequently observed in previous short-stem designs, negatively affecting offset, can be avoided. However, surgeons have to be aware of a possible leg lengthening.

  16. The influence of vegetation structure on spider species richness, diversity and community organization in the Apšuciems calcareous fen, Latvia

    Energy Technology Data Exchange (ETDEWEB)

    Štokmane, M.; Spuņģis, V.

    2016-07-01

    Calcareous fens are considered to be among the most threatened ecosystems of Europe. They are also one of the most diverse habitats as they support an incredibly rich and diverse range of plant and animal species. However, in spite of their diversity, calcareous fens are still poorly investigated, especially when referring to fen invertebrates, such as spiders. Because spiders are good bioindicators, knowledge of their ecology in rare and threatened habitats is of interest. The aim of this study was to document the composition and diversity of spider species, families and foraging guilds in the ground– and grass–layers of the Apšuciems calcareous fen, and to evaluate the influence of vegetation structure on spider community organization. In summer 2012, we collected ground–dwelling spiders using pitfall traps and grass–dwelling spiders using sweep–netting. A total of 2,937 spider individuals belonging to 19 families and 80 species was collected in the Apšuciems fen. Our results indicate that spider species and families tend to be stratified across the vertical structure of the habitat; the spider composition in the ground stratum differed from that in the grass stratum. On the contrary, however, the spider foraging guild structure between the ground–layer and the grass–layer was similar. Each of the two studied strata presented similar guilds in similar proportions. Our results also showed that spider composition differed considerably between fen parts and that much of this variability could be explained by the architectural properties of the habitat. More diverse vegetation generally supported a higher number of spider species. (Author)

  17. Physical behaviour of calcareous nannofossil ooze and effects of clay and organic matter on pelagic sediment stability: experimental approach using laboratory flumes

    DEFF Research Database (Denmark)

    Buls, Toms

    This thesis explores the subject of physical behaviour of ancient calcareous nannofossil ooze that eventually formed kilometre-thick Upper Cretaceous chalk succession over vast areas of NW Europe and more than 65 Ma years later forms valuable hydrocarbon and ground-water reservoirs. This thesis...... porosity range (85–60 %). A transition from simple to complex erosional behaviour has been identified mostly when bed porosity decreases below 80 %. This complex erosion required definition of multiple erosion thresholds. Typically, erosion thresholds were increasing with decreasing bed porosity...

  18. Calcareous nannoplankton dating of the Late Quaternary deposits in Greece and the eastern Mediterranean: Case studies from terrestrial and marine sites

    Directory of Open Access Journals (Sweden)

    Maria V. Triantaphyllou

    2015-10-01

    Full Text Available The distribution and abundance of Emiliania huxleyi (E. huxleyi assemblages in the marine sediments of the Aravonitsa Plateau, Greece, and from the eastern Mediterranean are used (1 to evaluate the calcareous nannoplankton NN21a and NN21b biozones and the NN21a/NN21b boundary, and (2 to analyze the palaeoenvironmental and palaeoclimatic conditions prevailing in this interval. The sediment succession displays varied E. huxleyi assemblages and these are interpreted as reflecting climatic variability during marine isotope stages MIS 1–8.

  19. Geochemical response of a calcareous fen to road salt contamination during snow melt and precipitation events: Kampoosa Bog, Stockbridge, MA

    Science.gov (United States)

    Rhodes, A. L.; Guswa, A. J.

    2008-12-01

    Kampoosa Bog is the largest and most diverse calcareous lake-basin fen remaining in Massachusetts, and it is one of the state's elite Areas of Critical Environmental Concern (ACEC). The ground water chemistry of the fen has been greatly altered by road salt runoff (NaCl) from the Massachusetts Turnpike, which crosses the northern margin of the wetland complex. Ground water samples collected at different depths within the wetland, measurements of exchangeable Na from an eight-meter core, and hydraulic conductivity measurements suggest that ground water flow and contamination is largely a near- surface phenomenon. Detailed sampling of surface and ground waters during three spring snow melt events and one precipitation event characterizes the geochemical response of the wetland to hydrologic events. Overall, Na:Cl ratios for surface and ground water samples are less than one, and sodium and chloride imbalances suggest that 20-30% of sodium from rock salt is stored on cation exchange sites on organic material. Na:Cl ratios greater than one for fen ground water sampled during Snow Melt 2007 suggest that sodium can be released from cation exchange sites back to ground water under dilute conditions. The total mass of Na and Cl exported from the wetland is greatest under conditions of high discharge. The flux of dissolved salts at the outlet of the fen during Snow Melt 2005 accounts for ~ 24% Na and ~ 32% Cl of rock salt added to the Massachusetts Turnpike during 2004-2005. Estimates of annual fluxes of Na and Cl are on par with the amount of road salt applied, and sodium and chloride concentrations in shallow groundwater have decreased since 2002. The months of March, April and May are the primary months for salt export, accounting for more than half of the annual salt flux in 2005. Concerning the annual net export of sodium and chloride, large rain events may be more important with removing dissolved salts from the fen than snow melt because snow melt also is a time when

  20. Effects of CO2-driven acidification of seawater on the calcification process in the calcareous hydrozoan Millepora alcicornis (Linnaeus, 1758)

    Science.gov (United States)

    de Barros Marangoni, Laura Fernandes; Calderon, Emiliano Nicolas; Marques, Joseane Aparecida; Duarte, Gustavo Adolpho Santos; Pereira, Cristiano Macedo; e Castro, Clovis Barreira; Bianchini, Adalto

    2017-12-01

    Ocean acidification is expected to intensify due to increasing levels in the partial pressure of atmospheric CO2 ( pCO2). This could negatively affect major calcifying reef organisms. In this study, the effects of different levels of CO2-driven acidification of seawater (control: pH 8.1; moderate: pH 7.8; intermediate: pH 7.5; and severe: pH 7.2) on the net calcification rate and activity of enzymes related to the calcification process (Ca-ATPase and carbonic anhydrase) were evaluated in the calcareous hydrozoan Millepora alcicornis. The experiment was run for 30 d using a marine mesocosm system. Net calcification ratio was significantly reduced in hydrocorals exposed to intermediate seawater acidification for 16 d and to severe seawater acidification for 16 d or 30 d, compared to animals at control conditions. However, only hydrocorals exposed to severe seawater acidification showed lower net calcification rates than those exposed to control conditions for 30 d. In accordance, the activities of enzymes involved in the calcification process markedly increased in hydrocorals exposed to reduced pH. Ca-ATPase seemed to be more sensitive to seawater acidification than carbonic anhydrase as it increased in hydrocorals exposed to intermediate and severe seawater acidification for 30 d, while carbonic anhydrase activity was only stimulated under severe seawater acidification. Therefore, our findings clearly show that the hydrocoral M. alcicornis is able to cope, to some extent, with long-term CO2-driven acidification of seawater (pH ≥ 7.5). In addition, they show that Ca-ATPase plays a key role in the maintenance of calcification rate under scenarios of moderate and intermediate levels of seawater acidification. However, the observed increase in Ca-ATPase and carbonic anhydrase activity was not enough to compensate for the effects of CO2-driven reduction in seawater pH on the net calcification rate of the hydrocoral M. alcicornis under a scenario of severe ocean

  1. Formation of Zn-rich phyllosilicate, Zn-layered double hydroxide and hydrozincite in contaminated calcareous soils

    Energy Technology Data Exchange (ETDEWEB)

    Jacquat, Olivier; Voegelin, Andreas; Villard, Andre; Marcus, Matthew A.; Kretzschmar, Ruben

    2007-10-15

    Recent studies demonstrated that Zn-phyllosilicate- and Zn-layered double hydroxide-type (Zn-LDH) precipitates may form in contaminated soils. However, the influence of soil properties and Zn content on the quantity and type of precipitate forming has not been studied in detail so far. In this work, we determined the speciation of Zn in six carbonate-rich surface soils (pH 6.2 to 7.5) contaminated by aqueous Zn in the runoff from galvanized power line towers (1322 to 30090 mg/kg Zn). Based on 12 bulk and 23 microfocused extended X-ray absorption fine structure (EXAFS) spectra, the number, type and proportion of Zn species were derived using principal component analysis, target testing, and linear combination fitting. Nearly pure Zn-rich phyllosilicate and Zn-LDH were identified at different locations within a single soil horizon, suggesting that the local availabilities of Al and Si controlled the type of precipitate forming. Hydrozincite was identified on the surfaces of limestone particles that were not in direct contact with the soil clay matrix. With increasing Zn loading of the soils, the percentage of precipitated Zn increased from {approx}20% to {approx}80%, while the precipitate type shifted from Zn-phyllosilicate and/or Zn-LDH at the lowest studied soil Zn contents over predominantly Zn-LDH at intermediate loadings to hydrozincite in extremely contaminated soils. These trends were in agreement with the solubility of Zn in equilibrium with these phases. Sequential extractions showed that large fractions of soil Zn ({approx}30% to {approx}80%) as well as of synthetic Zn-kerolite, Zn-LDH, and hydrozincite spiked into uncontaminated soil were readily extracted by 1 M NH{sub 4}NO{sub 3} followed by 1 M NH{sub 4}-acetate at pH 6.0. Even though the formation of Zn precipitates allows for the retention of Zn in excess to the adsorption capacity of calcareous soils, the long-term immobilization potential of these precipitates is limited.

  2. Characterization of bacterial diversity associated with calcareous deposits and drip-waters, and isolation of calcifying bacteria from two Colombian mines.

    Science.gov (United States)

    García G, Mariandrea; Márquez G, Marco Antonio; Moreno H, Claudia Ximena

    2016-01-01

    Bacterial carbonate precipitation has implications in geological processes and important biotechnological applications. Bacteria capable of precipitating carbonates have been isolated from different calcium carbonate deposits (speleothems) in caves, soil, freshwater and seawater around the world. However, the diversity of bacteria from calcareous deposits in Colombia, and their ability to precipitate carbonates, remains unknown. In this study, conventional microbiological methods and molecular tools, such as temporal temperature gradient electrophoresis (TTGE), were used to assess the composition of bacterial communities associated with carbonate deposits and drip-waters from two Colombian mines. A genetic analysis of these bacterial communities revealed a similar level of diversity, based on the number of bands detected using TTGE. The dominant phylogenetic affiliations of the bacteria, determined using 16S rRNA gene sequencing, were grouped into two phyla: Proteobacteria and Firmicutes. Within these phyla, seven genera were capable of precipitating calcium carbonates: Lysinibacillus, Bacillus, Strenotophomonas, Brevibacillus, Methylobacterium, Aeromicrobium and Acinetobacter. FTIR and SEM/EDX were used to analyze calcium carbonate crystals produced by isolated Acinetobacter gyllenbergii. The results showed that rhombohedral and angular calcite crystals with sizes of 90μm were precipitated. This research provides information regarding the presence of complex bacterial communities in secondary carbonate deposits from mines and their ability to precipitate calcium carbonate from calcareous deposits of Colombian mines. Copyright © 2015 Elsevier GmbH. All rights reserved.

  3. Influence of flooding and metal immobilising soil amendments on availability of metals for willows and earthworms in calcareous dredged sediment-derived soils

    Energy Technology Data Exchange (ETDEWEB)

    Vandecasteele, Bart, E-mail: bart.vandecasteele@ilvo.vlaanderen.b [Institute for Agricultural and Fisheries Research (ILVO), Scientific Institute of the Flemish Government, Burg. Van Gansberghelaan 109, B-9820 Merelbeke (Belgium); Du Laing, Gijs [Ghent University, Department of Applied Analytical and Physical Chemistry, Coupure 653, B-9000 Ghent (Belgium); Lettens, Suzanna [Research Institute for Nature and Forest (INBO), Scientific Institute of the Flemish Government, Gaverstraat 4, B-9500 Geraardsbergen (Belgium); Jordaens, Kurt [Department of Biology, Evolutionary Biology Group, University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp (Belgium); Tack, Filip M.G. [Ghent University, Department of Applied Analytical and Physical Chemistry, Coupure 653, B-9000 Ghent (Belgium)

    2010-06-15

    Soil amendments previously shown to be effective in reducing metal bioavailability and/or mobility in calcareous metal-polluted soils were tested on a calcareous dredged sediment-derived soil with 26 mg Cd/kg dry soil, 2200 mg Cr/kg dry soil, 220 mg Pb/kg dry soil, and 3000 mg Zn/kg dry soil. The amendments were 5% modified aluminosilicate (AS), 10% w/w lignin, 1% w/w diammonium phosphate (DAP, (NH{sub 4}){sub 2}HPO{sub 4}), 1% w/w MnO, and 5% w/w CaSO{sub 4}. In an additional treatment, the contaminated soil was submerged. Endpoints were metal uptake in Salix cinerea and Lumbricus terrestris, and effect on oxidation-reduction potential (ORP) in submerged soils. Results illustrated that the selected soil amendments were not effective in reducing ecological risk to vegetation or soil inhabiting invertebrates, as metal uptake in willows and earthworms did not significantly decrease following their application. Flooding the polluted soil resulted in metal uptake in S. cinerea comparable with concentrations for an uncontaminated soil. - Some soil amendments resulted in higher metal uptake by earthworms and willows than when the polluted soil was not amended but submersion of the polluted soil resulted in reduced Cd and Zn uptake in Salix cinerea.

  4. Weathering of a Roman Mosaic-A Biological and Quantitative Study on In Vitro Colonization of Calcareous Tesserae by Phototrophic Microorganisms.

    Directory of Open Access Journals (Sweden)

    Addolorata Marasco

    Full Text Available The potential impact of cyanobacteria and microalgae on the weathering of calcareous tesserae from a Roman mosaic of the II Century CE has been followed through in vitro experiments. Laboratory tests were carried out by inoculating mosaic tiles with single strains of Cyanobacteria or Chlorophyta to evaluate the roles of pioneer phototrophic microrganism on the resulting architecture of biofilms. The interaction between tesserae and strains was assessed at the whole substratum and micrometer scales, by image analysis and Confocal Laser Scanning (CLS microscopy, respectively. The biofilm surface coverage on each tessera varied from 19% (Fischerella ambigua to 97% (Microcoleus autumnalis. Cyanobacteria showed a better growth on calcareous tesserae, whereas the only green alga attaining a superficial coverage higher than 50% was Coelastrella rubescens. CLS microscopy evidenced two different types of spatial arrangement of the phototrophic organisms on the tesserae, that were defined as compact or porous, respectively. In the first one was measured a reduced number of empty spaces between cells or filaments, whereas in the second type, a reticulate texture allowed the presence of numerous empty volumes. The colonization processes observed are an intrinsic characteristic of each strain. We have proposed a colonization index IC as a sensible tool to describe, in a quantitative way, the pioneering attitude of each photosynthetic microorganism to colonize lithic substrates under laboratory conditions.

  5. Extreme diagenesis displayed by Pliocene-Pleistocene Calcareous Nannofossils in IODP Hole 1396A, adjacent to Montserrat Island in the Lesser Antilles

    Science.gov (United States)

    Aljahdali, M. H.; Behzad, A.; Missimer, T. M.; Wise, S. W.; Scientists, E.

    2013-12-01

    Adjacent to Montserrat Island in the Lesser Antilles of the Caribbean Sea, Integrated Ocean Drilling Program (IODP) Site 1396 recovered lower Pliocene to Pleistocene calcareous nannofossil assemblages (CN11 to CN15) that range between common to abundant and display a variety of preservations. High-resolution Scanning Electron Microscopy (SEM) observation of calcareous nannofossil assemblages in selected samples from Hole 1396A, shows severe diagenesis (overgrowth and/or dissolution) even near the top of the sequence. The nannofossil assemblages in this relatively shallow basin (e.g., 800 m) reveal abnormal diagenesis for such young specimens that are quite similar to the heavy overgrowths and dissolution generally seen only in older deposits (e.g., Cretaceous). Our hypothesis is that volcanic activity in the region probably induced this extreme diagenesis. A more detailed examination of these samples should provide a better understanding of the progression of carbonate diagenesis in this basin. The nannofossil biostratigraphy and magnetostratigraphy at Site 1396 also suggest lower sedimentation rates in the Pleistocene than in the Pliocene. A comparison site (ODP Leg 165 Site 1000) in the Caribbean Sea also shows a similar sedimentation-rate pattern. This we interpret as a regional event caused by the closure of the Central American Seaway.

  6. Cardoon (Cynara cardunculus L.) biomass production in a calcareous soil amended with sewage sludge compost and irrigated with sewage water

    Science.gov (United States)

    Lag, A.; Gomez, I.; Navarro-Pedreño, J.; Melendez, I.; Perez Gimeno, A.; Soriano-Disla, J. M.

    2010-05-01

    Energy use is one of the most important current global issues. Traditional energetic resources are limited and its use generates environmental problems, i.e. Global Warming, thus it is necessary to find alternative ways to produce energy. Energy crops represent one step towards sustainability but it must be coupled with appropriate land use and management adapted to local conditions. Moreover, positive effects like soil conservation; economical improvement of rural areas and CO2 storage could be achieved. Treated sewage water and sewage sludge compost were used as low-cost inputs for nutrition and irrigation, to cultivate cardoon (Cynara cardunculus L.) a perennial Mediterranean crop. The aim of the present field experiment was to ascertain the optimum dose of compost application to obtain maximum biomass production. Four compost treatments were applied by triplicate (D1=0; D2=30; D3=50; D4=70 ton/ha) and forty eight cardoon plants were placed in each plot, 12 per treatment, in a calcareous soil (CLfv; WRB, 2006) plot, located in the South East of Spain, in semi-arid conditions. The experiment was developed for one cardoon productive cycle (one year); soil was sampled three times (October, April and July). Soil, compost and treated sewage irrigation water were analyzed (physical and chemical properties). Stalk, capitula and leave weight as well as height and total biomass production were the parameters determined for cardoon samples. Analyses of variance (ANOVA) at p=0,05 significance level were performed to detect differences among treatments for each sampling/plot and to study soil parameters evolution and biomass production for each plot/dose. Several statistical differences in soil were found between treatments for extractable zinc, magnesium and phosphorus; as well as Kjeldahl nitrogen and organic carbon due to compost application, showing a gradual increase of nutrients from D1 to D4. However, considering the evolution of soil parameters along time, pH was

  7. Oceanic ecosystem dynamics during gigantic volcanic episodes: the Ontong Java and Manihiki Plateaus recorded by calcareous nannoplankton. (Invited)

    Science.gov (United States)

    Erba, E.

    2010-12-01

    dwarfism and malformation represent adjustments to survive lower pH. Deep-water acidification occurs with a delay of 25-30 thousand years: a dissolution event recording 1 to 2km shallowing of the Calcite Compensation Depth anticipated the onset of anoxic sedimentation. A major acceleration in weathering has been identified in the lowermost part of OAE1a. After acidification-dissolution climax, nannoplankton and carbonate recovery developed over ~160 kyr, under persisting global dysoxia-anoxia. This recovery presumably implies a stasis of the LIP activity and gradual buffering of ocean acidification or a decrease in volcanogenic CO2 emissions and consistently higher CO2 drawdown through Corg burial and/or weathering. Rising CO2 and surface-ocean acidification during OAE1a triggered false extinctions among calcareous nannoplankton. Conversely, a major origination episode starts approximately 1 My before global anoxia and persists through OAE1a and associated acidification. Increasing pCO2 caused complex and species-specific reactions, including production of r-strategist taxa, which, however, secreted dwarf and malformed coccoliths as a strategy to overcome acidification.

  8. Pleistocene to Miocene Calcareous Nannofossil Biostratigraphy from IODP Expedition 334 Hole U1381A and Expedition 352 Hole U1439A

    Science.gov (United States)

    Power, M.; Scientists, I. E.; Avery, A. J.

    2015-12-01

    Samples for this study were collected from drill cores taken during the Integrated Ocean Drilling Program (IODP) Expeditions 334 and 352 at Sites U1381 and U1439, respectively. Both of these expeditions were focused around subduction zones and, therefore, had priorities to determine time frames for the initiation of subduction. There are two main objectives for this study, the first being to age-date Pleistocene to Miocene sediments from the western offshore continental margin of Costa Rica (IODP Expedition 334) via calcareous nannofossils. The second objective is to age-date the Miocene sediments from the fore-arc of the Izu-Bonin-Mariana system, east of Japan (IODP Expedition 352), using calcareous nannofossils. Shore-based analysis allows for high-resolution study to determine exact biostratigraphic zonations. These zonations reflect specific time frames based on the occurrence or non-occurrence of certain nannofossil species. Once these zonations are determined, scientists can use the data to identify the initiation of seismic processes that often occur in these regions. Calcareous nannofossil biostratigraphy has now provided zonations for the samples taken from IODP Expedition 334 cores. Samples from core 6R are assigned to the Pleistocene nannofossil Zone NN19 due to the presence ofPseudoemiliania lacunosa and the absence of Emiliania huxleyi. Using the zonal scheme by de Kaenel (1999), this can further be broken down into Event 18 due to the presence of Gephyrocapsa oceanica larger than 4 μm but less than 5 μm, the presence of Calcidiscus macintyrei smaller than 11 μm, and the absence ofGephyrocapsa caribbeanica larger than 4 μm. De Kaenel (1999) has assigned this event datum an age of 1.718 Ma using orbital time scales and oxygen isotope data. Below these samples, an extensive hiatus ranges from the Pleistocene to the early Miocene. Samples from cores 7R through 10R are assigned to nannofossil zone NN5; however, it is impossible to constrain the top of

  9. A transgressive Santonian-Campanian boundary sequence revisited - High resolution planktonic and benthic foraminifera stratigraphy of the Schattau section, Northern Calcareous Alps.

    Science.gov (United States)

    Wolfgring, Erik; Wagreich, Michael; Summesberger, Herbert; Kroh, Andreas

    2016-04-01

    The Schattau section is part of the Austrian Gosau Group, Northern Calcareous Alps. We record a Santonian to early Campanian transgressive sequence. Previous investigations already provide a biostratigraphic framework; a multidisciplinary study to reveal the local stratigraphy and palaeoenvironmental properties: Planktonic foraminifera, calcareous nannoplankton, ammonite, echinoid and crinoid biostratigraphy data suggest a Santonian to earliest Campanian age for this section (see Wagreich et al., 2009). This work aims at a high resolution assessment of foraminiferal assemblages recorded from a time interval that has undergone significant palaeoenvironmental changes. The Santonian Hochmoos Formation, with the Sandkalkbank Member representing it's topmost subunit, is overlain by the Santonian to Campanian Bibereck Formation. While The Hochmoos Formation records a shallowing succession that finds the Sandkalkbank Member (representing very shallow conditions, sometimes sub aerial exposure) at its top. The overlying Bibereck Formation records a distinct deepening trend displaying increasingly marine, neritic to outer neritic conditions. The stratigraphically older subunits of the Schattau sections are characterised by abundant larger benthic foraminifera (Nummofallotia cretacea), miliolid foraminifera (Quinqueloculina spp, Spiroloculina fassistomata) as well as rotaliid foraminifera (Hoeglundia spp., Gavellina spp.). The Sandkalkbank member marks the end of the shallow water sequence recorded from foraminifera assemblages at the Schattau section. Up section communities are characterised by increasing share of planktonic foraminifera. Biostratigraphic marker fossils like Dicarinella asymetrica and Sigalia sp. (decoratissima?) were identified and indicate a Santonian age for the Bibereck Formation. The appearance of Globotruncanita elevata and disappearance of D. asymetrica and Sigalia sp. Suggests an early Campanian age for the topmost part of the Schattau section

  10. SARSTEINIA BABAI N. GEN., N. SP., A NEW PROBLEMATIC SPONGE (INOZOA? FROM THE LATE JURASSIC OF THE NORTHERN CALCAREOUS ALPS, AUSTRIA

    Directory of Open Access Journals (Sweden)

    FELIX SCHLAGINTWEIT

    2006-07-01

    Full Text Available The new problematic sponge Sarsteinia babai n. gen., n. sp. is described from the Kimmeridgian to Tithonian Plassen and Lärchberg Formations of the Northern Calcareous Alps of Austria. The type-locality is the Sarsteinalm north of Mount Hoher Sarstein in the Austrian Salzkammergut, other findings come from Mount Sandling, Mount Jainzen, Mount Trisselwand and the Litzlkogel-Gerhardstein-complex west of Lofer. Most findings can be attributed to a fore-reef to upper slope facies or slope-of-toe breccias, small fragments can occasionally also be found in the back-reef facies. The suprageneric systematic position of the new sponge is unknown so far since it shows morphological characteristics known from Inozoa but also from "stromatoporoids".

  11. Noninvasive monitoring of moisture uptake in Ca(NO3)2 -polluted calcareous stones by 1H-NMR relaxometry.

    Science.gov (United States)

    Casieri, Cinzia; Terenzi, Camilla; De Luca, Francesco

    2015-01-01

    NMR transverse relaxation time (T(2)) distribution of (1)H nuclei of water has been used to monitor the moisture condensation kinetics in Ca(NO(3))(2)  · (4)H(2)O-polluted Lecce stone, a calcareous stone with highly regular porous structure often utilized as basic material in Baroque buildings. Polluted samples have been exposed to water vapor adsorption at controlled relative humidity to mimic environmental conditions. In presence of pollutants, the T(2) distributions of water in stone exhibit a range of relaxation time values and amplitudes not observed in the unpolluted case. These characteristics could be exploited for in situ noninvasive detection of salt pollution in Lecce stone or as damage precursors in architectural buildings of cultural heritage interest. Copyright © 2014 John Wiley & Sons, Ltd.

  12. Layered Growth and Crystallization in Calcareous Biominerals: Impact of Structural and Chemical Evidence on Two Major Concepts in Invertebrate Biomineralization Studies

    Directory of Open Access Journals (Sweden)

    Jean-Pierre Cuif

    2012-02-01

    Full Text Available In several recent models of invertebrate skeletogenesis, Ca-carbonate crystallization occurs within a liquid-filled chamber. No explanation is given neither for the simultaneous occurrence of distinct polymorphs of Ca-carbonate within these liquid volumes, nor for the spatial arrangement of the mineral units which are always organized in species-specific structural sequences. Results of a series of physical characterizations applied to reference skeletal materials reveal the inadequacy of this liquid-filled chamber model to account for structural and chemical properties of the shell building units. Simultaneously, these data provide convergent pieces of evidence for a specific mode of crystallization developed throughout various invertebrate phyla, supporting the hypothesized “common strategy” based on a multi-scaled control exerted on formation of their calcareous hard parts.

  13. Calcareous nannofossil biostratigraphy of Sarcheshmeh and Sanganeh formations at Qaleh Jegh and Yazdan Abad sections (West of Kopet-Dagh Basin

    Directory of Open Access Journals (Sweden)

    Azam Gholami Fard

    2017-03-01

    Full Text Available 1-    Introduction Kopet Dagh Basin is located on the northeast of Iran, extending over Iran, Turkmenistan and Afghanistan with a west-northwest to east-southeast trend. The Iranian part of the basin is located between 61°14ˊ and 54°00ˊE and 38°15ˊ and 35°38ˊ N. It constitutes the second most important hydrocarbon province of Iran after Zagros Basin. Cretaceous sediments are well developed and extensively exposed in this basin. In order to study the Biostratigraphy of Sarcheshme and Sanganeh Formations, the calcareous nannofossil assemblages have been investigated in two stratigraphic sections. Shokri (2000, Hadavi and Shokri (2000, Hadavi and Bodaghi (2000 & 2009, Dehghan (2002, Mahanipour et al. (2011a,b & 2012 and Mahanipour and Kani (2015 studied the calcareous nannofossil biostratigraphy of Sarcheshme or Sanganeh Formation.   2-    Material & Methods The studied sections, the Qaleh Jegh section (located at a distance of 35 km to the northeast of Bojnord, on the Baba Boland mountain; N37°47ˊ57˝ and E57°16ˊ53˝ and Yazdan Abad section (located at north of Yazdan Abad village; N37°55ˊ34˝ and E57°35ˊ10˝. Sarcheshmeh Formation conformably overlies the Tirgan Formation and is in turn overlain by the Sanganeh Formation in both sections and Atamir Formation conformably overlies the Sanganeh Formation. Sarcheshmeh Formation measures 2660 m in Qaleh Jegh section and comprises argillaceous limestone (with limestone intercalations in lower part and shale (with limestone intercalation in upper part. A  fossiliferous limestone separates the Sarcheshmeh and Sanganeh. Sanganeh Formation measures 1400 m and consists of siltstones (with sandstone, shale or limestone intercalation in lower part and shale containing chert nodules (with siltstone intercalation in upper part. At Yazadn Abad section the 655 m thick succession of Sarcheshmeh Formation consists of alternating argillaceous limestone and limestone in lower part and

  14. Short-Term Responses of Soil Respiration and C-Cycle Enzyme Activities to Additions of Biochar and Urea in a Calcareous Soil

    Science.gov (United States)

    Song, Dali; Xi, Xiangyin; Huang, Shaomin; Liang, Guoqing; Sun, Jingwen; Zhou, Wei; Wang, Xiubin

    2016-01-01

    Biochar (BC) addition to soil is a proposed strategy to enhance soil fertility and crop productivity. However, there is limited knowledge regarding responses of soil respiration and C-cycle enzyme activities to BC and nitrogen (N) additions in a calcareous soil. A 56-day incubation experiment was conducted to investigate the combined effects of BC addition rates (0, 0.5, 1.0, 2.5 and 5.0% by mass) and urea (U) application on soil nutrients, soil respiration and C-cycle enzyme activities in a calcareous soil in the North China Plain. Our results showed soil pH values in both U-only and U plus BC treatments significantly decreased within the first 14 days and then stabilized, and CO2emission rate in all U plus BC soils decreased exponentially, while there was no significant difference in the contents of soil total organic carbon (TOC), dissolved organic carbon (DOC), total nitrogen (TN), and C/N ratio in each treatment over time. At each incubation time, soil pH, electrical conductivity (EC), TOC, TN, C/N ratio, DOC and cumulative CO2 emission significantly increased with increasing BC addition rate, while soil potential activities of the four hydrolytic enzymes increased first and then decreased with increasing BC addition rate, with the largest values in the U + 1.0%BC treatment. However, phenol oxidase activity in all U plus BC soils showed a decreasing trend with the increase of BC addition rate. Our results suggest that U plus BC application at a rate of 1% promotes increases in hydrolytic enzymes, does not highly increase C/N and C mineralization, and can improve in soil fertility. PMID:27589265

  15. Biocalcite, a multifunctional inorganic polymer: Building block for calcareous sponge spicules and bioseed for the synthesis of calcium phosphate-based bone

    Directory of Open Access Journals (Sweden)

    Xiaohong Wang

    2014-05-01

    Full Text Available Calcium carbonate is the material that builds up the spicules of the calcareous sponges. Recent results revealed that the calcium carbonate/biocalcite-based spicular skeleton of these animals is formed through an enzymatic mechanism, such as the skeleton of the siliceous sponges, evolutionarily the oldest animals that consist of biosilica. The enzyme that mediates the calcium carbonate deposition has been identified as a carbonic anhydrase (CA and has been cloned from the calcareous sponge species Sycon raphanus. Calcium carbonate deposits are also found in vertebrate bones besides the main constituent, calcium phosphate/hydroxyapatite (HA. Evidence has been presented that during the initial phase of HA synthesis poorly crystalline carbonated apatite is deposited. Recent data summarized here indicate that during early bone formation calcium carbonate deposits enzymatically formed by CA, act as potential bioseeds for the precipitation of calcium phosphate mineral onto bone-forming osteoblasts. Two different calcium carbonate phases have been found during CA-driven enzymatic calcium carbonate deposition in in vitro assays: calcite crystals and round-shaped vaterite deposits. The CA provides a new target of potential anabolic agents for treatment of bone diseases; a first CA activator stimulating the CA-driven calcium carbonate deposition has been identified. In addition, the CA-driven calcium carbonate crystal formation can be frozen at the vaterite state in the presence of silintaphin-2, an aspartic acid/glutamic acid-rich sponge-specific protein. The discovery that calcium carbonate crystals act as bioseeds in human bone formation may allow the development of novel biomimetic scaffolds for bone tissue engineering. Na-alginate hydrogels, enriched with biosilica, have recently been demonstrated as a suitable matrix to embed bone forming cells for rapid prototyping bioprinting/3D cell printing applications.

  16. Calcareous nannofossil biostratigraphy and geochronology of Neogene trench-slope cover sediments in the south Boso Peninsula, central Japan: Implications for the development of a shallow accretionary complex

    Science.gov (United States)

    Chiyonobu, Shun; Yamamoto, Yuzuru; Saito, Saneatsu

    2017-07-01

    The geological structure and calcareous nannofossil biostratigraphy of the Middle to Late Miocene trench-slope succession in the southern Boso Peninsula, central Japan, were examined to obtain chronological constraints on the accretion and formation of the trench-slope architecture. As a result, trench-slope cover sediments (Kinone and Amatsu Formations) are clearly distinguishable from the Early Miocene Hota accretionary complex (Hota Group). The Hota accretionary complex was deposited below the carbonate compensation depth (CCD) and was affected by intense shearing, forming an east-west trending and south-verging fold and thrust belt. In contrast, the trench-slope cover sediments basically have a homoclinal dip, except at the northern rim where they are bounded by fault contact. They contain many species of calcareous nannofossils and foraminifers, which are indicative of their depositional environment above the CCD, and they show shallowing-upward sedimentary structures. Biostratigraphy revealed that the depositional age of the trench-slope sediments is ca. 15-5.5 Ma, suggesting that there is an approximately 2 myr hiatus beween the Miura Group and the underlying accretionary prism. Based on these results, the age of accretion of the Hota Group is inferred to be between ca. 17-15 Ma, and the group is covered by trench-slope sediments overlain on it after ca. 15 Ma. The timing of accretion and the age of the trench-slope basin tend to be younger southward of the Boso Peninsula. The accretionary system of the Boso Peninsula apparently developed in two stages, in the Middle Miocene and in the Late Miocene to Pliocene.

  17. Short-Term Responses of Soil Respiration and C-Cycle Enzyme Activities to Additions of Biochar and Urea in a Calcareous Soil.

    Directory of Open Access Journals (Sweden)

    Dali Song

    Full Text Available Biochar (BC addition to soil is a proposed strategy to enhance soil fertility and crop productivity. However, there is limited knowledge regarding responses of soil respiration and C-cycle enzyme activities to BC and nitrogen (N additions in a calcareous soil. A 56-day incubation experiment was conducted to investigate the combined effects of BC addition rates (0, 0.5, 1.0, 2.5 and 5.0% by mass and urea (U application on soil nutrients, soil respiration and C-cycle enzyme activities in a calcareous soil in the North China Plain. Our results showed soil pH values in both U-only and U plus BC treatments significantly decreased within the first 14 days and then stabilized, and CO2emission rate in all U plus BC soils decreased exponentially, while there was no significant difference in the contents of soil total organic carbon (TOC, dissolved organic carbon (DOC, total nitrogen (TN, and C/N ratio in each treatment over time. At each incubation time, soil pH, electrical conductivity (EC, TOC, TN, C/N ratio, DOC and cumulative CO2 emission significantly increased with increasing BC addition rate, while soil potential activities of the four hydrolytic enzymes increased first and then decreased with increasing BC addition rate, with the largest values in the U + 1.0%BC treatment. However, phenol oxidase activity in all U plus BC soils showed a decreasing trend with the increase of BC addition rate. Our results suggest that U plus BC application at a rate of 1% promotes increases in hydrolytic enzymes, does not highly increase C/N and C mineralization, and can improve in soil fertility.

  18. THE EARLY PLIOCENE MAMMAL ASSEMBLAGE OF VAL DI PUGNA (TUSCANY, ITALY IN THE LIGHT OF CALCAREOUS PLANKTON BIOSTRATIGRAPHICAL DATA AND PALEOECOLOGICAL OBSERVATIONS

    Directory of Open Access Journals (Sweden)

    GIOVANNI BIANUCCI

    2001-11-01

    Full Text Available The stratigraphy of clayey and sandy beds outcropping in Val di Pugna locality near Siena (Tuscany, Italy celebrated for the past finds of fossil mammalian remains, is studied here. The research is aimed to date and define the depositional environment of the sediments that yielded fossil bones of known provenance.  Two sequences have been studied in detail; they are located near the hamlets of Ruffolo and Case il Poggio, where both marine and land mammal remains had been found. The integrated biostratigraphic analysis of the planktonic foraminifers and calcareous nannoplankton indicates that the deposits straddle the transition from the Zone MPL3 to MPL4 of the planktonic foraminifer biostratigraphic scale, which is correlated with the Reticulofenestra pseudoumbilicus Zone (MNN14-15 Zone of the calcareous nannoplankton scale. The sedimentary characters and the faunal content are suggestive of a progressively deepening marine environment, with a transition from upper shoreface deposits to lower shoreface-offshore deposits. The vertebrates include a cetacean (Tusciziphis crispus and a sirenid (Metaxyterium gervaisi amongst the marine mammals, while the land mammals are represented by a rhino (Stephanorhinus jeanvireti and a bovid (Alephis lyrix. The sirenid remains are likely the only autochthonous elements because of their ecologic consistency with the depositional environment of the embedding sediments. The other fossil specimens are interpreted here as parts of decaying and floating carcasses that deposited their bones as they drifted away, inflated by decomposition gasses.The biostratigraphy of the sites permits to date the fossil bones. Noteworthy occurrences are those of Stephanorhinus jeanvireti and Alephis lyrix in levels correlated with Zone MN14, since they are usually reported in Zone MN16 and Zone MN15 assemblages, respectively.   

  19. Effects of nitrogen and phosphorus fertilizer on crop yields in a field pea-spring wheat-potato rotation system with calcareous soil in semi-arid environments

    Directory of Open Access Journals (Sweden)

    Chang-An Liu

    2016-06-01

    Full Text Available The object of the present study was to investigate the yield-affecting mechanisms influenced by N and P applications in rainfed areas with calcareous soil. The experimental treatments were as follows: NF (no fertilizer, N (nitrogen, P (phosphorus, and NP (nitrogen plus phosphorus in a field pea-spring wheat-potato cropping system. This study was conducted over six years (2003-2008 on China’s semi-arid Loess Plateau. The fertilizer treatments were found to decrease the soil water content more than the NF treatment in each of the growing seasons. The annual average yields of the field pea crops during the entire experimental period were 635, 677, 858, and 1117 kg/ha for the NF, N, P, and NP treatments, respectively. The annual average yields were 673, 547, 966, and 1056 kg/ha for the spring wheat crops for the NF, N, P, and NP treatments, respectively. Also, the annual average yields were 1476, 2120, 1480, and 2424 kg/ha for the potato crops for the NF, N, P, and NP treatments, respectively. In the second cycle of the three-year rotation, the pea and spring wheat yields in the P treatment were 1.2 and 2.8 times higher than that in the N treatment, respectively. Meanwhile, the potato crop yield in the N treatment was 3.1 times higher than that in the P treatment. In conclusion, the P fertilizer was found to increase the yields of the field pea and wheat crops, and the N fertilizer increased the potato crop yield in rainfed areas with calcareous soil.

  20. Effects of nitrogen and phosphorus fertilizer on crop yields in a field pea-spring wheat-potato rotation system with calcareous soil in semi-arid environments

    Energy Technology Data Exchange (ETDEWEB)

    Liu, C.A.; Zhang, S.; Hua, S.; Rao, X.

    2016-11-01

    The object of the present study was to investigate the yield-affecting mechanisms influenced by N and P applications in rainfed areas with calcareous soil. The experimental treatments were as follows: NF (no fertilizer), N (nitrogen), P (phosphorus), and NP (nitrogen plus phosphorus) in a field pea-spring wheat-potato cropping system. This study was conducted over six years (2003-2008) on China’s semi-arid Loess Plateau. The fertilizer treatments were found to decrease the soil water content more than the NF treatment in each of the growing seasons. The annual average yields of the field pea crops during the entire experimental period were 635, 677, 858, and 1117 kg/ha for the NF, N, P, and NP treatments, respectively. The annual average yields were 673, 547, 966, and 1056 kg/ha for the spring wheat crops for the NF, N, P, and NP treatments, respectively. Also, the annual average yields were 1476, 2120, 1480, and 2424 kg/ha for the potato crops for the NF, N, P, and NP treatments, respectively. In the second cycle of the three-year rotation, the pea and spring wheat yields in the P treatment were 1.2 and 2.8 times higher than that in the N treatment, respectively. Meanwhile, the potato crop yield in the N treatment was 3.1 times higher than that in the P treatment. In conclusion, the P fertilizer was found to increase the yields of the field pea and wheat crops, and the N fertilizer increased the potato crop yield in rainfed areas with calcareous soil. (Author)

  1. Simulation of Zinc Release Affected by Microbial Inoculation and Salinity Levels in a non-sterile Calcareous Soil Using kinetic Models

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    hamidreza boostani

    2017-02-01

    Full Text Available Introduction: Zinc (Zn is an important nutrient element for humans and plants that controls many biochemical and physiological functions of living organisms. Zinc deficiency is common in high pH, low organic matter, carbonatic, saline and sodic soils. Salinity is a major abiotic environmental stresses that limits growth and production in arid and semi-arid regions of the world. Bioavailability of Zn is low in calcareous and saline soils having high levels of pH and calcium. Desorption of Zinc (Zn from soil as influenced by biological activities is one of the important factors that control Zn bioavailability. Few reports on the effects of salinity on the availability and desorption kinetics of Zn are available. Rupa et al. (2000 reported that increasing the salt concentration led to increase Zn desorption from soil due to ion competition on soil exchangeable sites. Different kinetic equations have been used to describe the release kinetics of nutrients. Reyhanitabar and Gilkes (2010 found that the power function model was the best equation to describe the release of Zn from some calcareous soil of Iran, whereas Baranimotlagh and Gholami (2013 stated that the best model for describing Zn desorption from 15 calcareous soils of Iran was the first-order equation.less attention has been paid to kinetics of Zn release by DTPA extractant over time by inoculation of plant growth promoting rhizobacteria and mycorrhizae fungi in comination with soil salinity.The objective of this study was to evaluate the effect of plant growth promoting rhizobacteria (PGPR and mycorrhizae fungi (MF inoculation on release kinetic of Zn in a calcareous soil at different salinity levels after in cornplantation Materials and Methods: A composite sample of bulk soil from the surface horizon (0-30 cm of a calcareous soil from southern part of Iran was collected, air dried, passed through 2 mm sieve, and thoroughly mixed. Routine soil analysis was performed to determine some

  2. Leaching of radiostrontium in undisturbed columns of calcareous alluvial soil as affected by level of activity applied and rate of high calcium water of Tigris river

    International Nuclear Information System (INIS)

    Fahad, A.A.; Razaq, I.B.; Ali, A.W.

    1986-01-01

    Leaching of 85 Sr in calcareous alluvial medium textured soil was undertaken for 126 days. Radiostrontium in three levels of 4.62(L1), 9.25(L2), and 18.50(L3) MBq column -1 was applied to undisturbed soil columns, 110cm long and 12cm inner diameter. Irrigation water of Tigris river was used as a leaching solution supplied automatically in 1.4, 2.0, and 3.0cm day -1 by rain simulator systems. Gamma radiation along the soil columns was scanned periodically during the course of leaching. Leaching of Sr from the surface layer was in two stages. The first stage covered the first 22 days and the second included the following 104 days. Strontium retained (y) as a function of time (x) fitted reasonably well (r>0.96) to the equations y=a+mlnx and lny=a+mx for the first and the second stage, respectively. Tigris river irrigation water was found as effective as the dilute Ca solution (proposed by some investigators) in displacing Sr. The leaching with 3.0cm day -1 for 126 days resulted in 23, 23, and 21 per cent of total Sr remaining in the upper 5 cm of soil columns under L1, L2 and L3, respectively. However, the area under the distribution curves followed the ratio 1.0:2.4:3.7 under L1, L2, and L3, respectively. The pattern of Sr distribution in calcareous alluvial soil depended not only on the rate and amount of water application but also on the level of Sr applied. Although the soil columns were leached with 378 cm of water for 126 days, the Sr front did not pass the 30 cm depth. This finding indicates the high retention of this soil for Sr and the potential hazard of radiostrontium arising from its existence in the layer of maximum root density. (author). 18 refs., 2 figures, 2 tables

  3. Role of microbial inoculation and industrial by-product phosphogypsum in growth and nutrient uptake of maize (Zea mays L.) grown in calcareous soil.

    Science.gov (United States)

    Al-Enazy, Abdul-Aziz R; Al-Oud, Saud S; Al-Barakah, Fahad N; Usman, Adel Ra

    2017-08-01

    Alkaline soils with high calcium carbonate and low organic matter are deficient in plant nutrient availability. Use of organic and bio-fertilizers has been suggested to improve their properties. Therefore, a greenhouse experiment was conducted to evaluate the integrative role of phosphogypsum (PG; added at 0.0, 10, 30, and 50 g PG kg -1 ), cow manure (CM; added at 50 g kg -1 ) and mixed microbial inoculation (Incl.; Azotobacter chroococcum, and phosphate-solubilizing bacteria Bacillus megaterium var. phosphaticum and Pseudomonas fluorescens) on growth and nutrients (N, P, K, Fe, Mn, Zn and Cu) uptake of maize (Zea mays L.) in calcareous soil. Treatment effects on soil chemical and biological properties and the Cd and Pb availability to maize plants were also investigated. Applying PG decreased soil pH. The soil available P increased when soil was inoculated and/or treated with CM, especially with PG. The total microbial count and dehydrogenase activity were enhanced with PG+CM+Incl. Inoculated soils treated with PG showed significant increases in NPK uptake and maize plant growth. However, the most investigated treatments showed significant decreases in shoot micronutrients. Cd and Pb were not detected in maize shoots. Applying PG with microbial inoculation improved macronutrient uptake and plant growth. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  4. Interception of residual nitrate from a calcareous alluvial soil profile on the North China Plain by deep-rooted crops: A {sup 15}N tracer study

    Energy Technology Data Exchange (ETDEWEB)

    Ju, X.T. [Key Laboratory of Plant-Soil Interactions, Ministry of Education, College of Agricultural Resources and Environmental Sciences, China Agricultural University, 2 Yuan Ming Yuan West Road, Hai Dian District, Beijing 100094 (China)]. E-mail: juxt@cau.edu.cn; Gao, Q. [Key Laboratory of Plant-Soil Interactions, Ministry of Education, College of Agricultural Resources and Environmental Sciences, China Agricultural University, 2 Yuan Ming Yuan West Road, Hai Dian District, Beijing 100094 (China); College of Agricultural Resources and Environmental Sciences, Jilin Agricultural University, Changchun 130118 (China); Christie, P. [Key Laboratory of Plant-Soil Interactions, Ministry of Education, College of Agricultural Resources and Environmental Sciences, China Agricultural University, 2 Yuan Ming Yuan West Road, Hai Dian District, Beijing 100094 (China); Agricultural and Environmental Science Department, Queen' s University Belfast, Belfast BT9 5PX (United Kingdom); Zhang, F.S. [Key Laboratory of Plant-Soil Interactions, Ministry of Education, College of Agricultural Resources and Environmental Sciences, China Agricultural University, 2 Yuan Ming Yuan West Road, Hai Dian District, Beijing 100094 (China)

    2007-03-15

    {sup 15}N-labeled nitrate was injected into different depths of an alluvial calcareous soil profile on the North China Plain. Subsequent movement of NO{sub 3} {sup -}N and its recovery by deep-rooted maize (Zea mays L.) and shallow-rooted eggplant (Solanum melongena L.) were studied. Under conventional water and nutrient management the mean recoveries of {sup 15}N-labeled nitrate from K{sup 15}NO{sub 3} injected at depths 15, 45, and 75 cm were 22.4, 13.8, and 7.8% by maize and 7.9, 4.9, and 2.7% by eggplant. The recovery rate by maize at each soil depth was significantly higher than by eggplant. The deeper the injection of nitrate the smaller the distance of its downward movement and this corresponded with the movement of soil water during crop growth. Deeper rooting crops with high root length density and high water consumption may therefore be grown to utilize high concentrations of residual nitrate in the subsoil from previous intensive cropping and to protect the environment. - Deep-rooted crops have a greater capacity than shallow-rooted crops to intercept residual nitrate from the subsoil and restrict its movement down to the shallow groundw0010at.

  5. Abundance and size changes in the calcareous nannofossil Schizosphaerella - relation to sea-level and palaeoenvironmental change across the Sinemurian to earliest Toarcian of the Paris Basin

    Science.gov (United States)

    Peti, Leonie; Thibault, Nicolas

    2017-04-01

    The nannolith Schizosphaerella spp. was predominant in Early Jurassic calcareous nannofossil assemblages. Previous studies have shown a significant drop in abundance and mean size of Schizosphaerella during the early Toarcian Oceanic Anoxic Event which has been interpreted by some authors either as a calcification crisis due to increased pCO2, or as a response to increased nutrient availability, and/or greenhouse warming. Abundance and size changes in Schizosphaerella have here been thoroughly investigated throughout the upper Sinemurian to lowermost Toarcian (Early Jurassic) of the Sancerre-Couy core (Paris Basin) based on 116 samples. Our results show a stepwise rise in abundance of Schizosphaerella in the lower part of the investigated section and a rise in abundance of coccoliths during the major transgression of the Sinemurian, confirming that Schizosphaerella was better adapted to proximal areas than coccoliths. Mixture analysis of the biometric measurements show the existence of three populations of Schizosphaerella, interpreted as different morphotypes with different ecological affinities. Proximal, cool environmental conditions of the upper Sinemurian are associated with a dominance of the large population of Schizosphaerella. A dominance of the medium population, corresponds to cool surface waters and more distal conditions. Warm episodes are systematically linked to a dominance of the small population. Therefore we propose that the size response of Schizosphaerella throughout the Early Jurassic was rather a change in abundance of different ecophenotypes or (sub-) species of Schizosphaerella, with distinct affinities to temperature and proximal/distal environmental conditions.

  6. Nitrate leaching in a winter wheat-summer maize rotation on a calcareous soil as affected by nitrogen and straw management.

    Science.gov (United States)

    Huang, Tao; Ju, Xiaotang; Yang, Hao

    2017-02-08

    Nitrate leaching is one of the most important pathways of nitrogen (N) loss which leads to groundwater contamination or surface water eutrophication. Clarifying the rates, controlling factors and characteristics of nitrate leaching is the pre-requisite for proposing effective mitigation strategies. We investigated the effects of interactions among chemical N fertilizer, straw and manure applications on nitrogen leaching in an intensively managed calcareous Fluvo-aquic soil with winter wheat-summer maize cropping rotations on the North China Plain from October 2010 to September 2013 using ceramic suction cups and seepage water calculations based on a long-term field experiment. Annual nitrate leaching reached 38-60 kg N ha -1 from conventional N managements, but declined by 32-71% due to optimum N, compost manure or municipal waste treatments, respectively. Nitrate leaching concentrated in the summer maize season, and fewer leaching events with high amounts are the characteristics of nitrate leaching in this region. Overuse of chemical N fertilizers, high net mineralization and nitrification, together with predominance of rainfall in the summer season with light soil texture are the main controlling factors responsible for the high nitrate leaching loss in this soil-crop-climatic system.

  7. Calcareous nannoplankton and foraminiferal response to global Oligocene and Miocene climatic oscillations: a case study from the Western Carpathian segment of the Central Paratethys

    Directory of Open Access Journals (Sweden)

    Holcová Katarína

    2017-06-01

    Full Text Available The reactions of foraminiferal and calcareous nannoplankton assemblages to global warming and cooling events in the time intervals of ca. 27 to 19 Ma and 13.5 to 15 Ma (Oligocene and Miocene were studied in subtropical epicontinental seas influenced by local tectonic and palaeogeographic events (the Central Paratethys. Regardless of these local events, global climatic processes significantly influenced the palaeoenvironment within the marine basin. Warm intervals are characterized by a stable, humid climate and a high-nutrient regime, due primarily to increased continental input of phytodetritus and also locally due to seasonal upwelling. Coarse clastics deposited in a hyposaline environment characterize the marginal part of the basin. Aridification events causing decreased riverine input and consequent nutrient decreases, characterized cold intervals. Apparent seasonality, as well as catastrophic climatic events, induced stress conditions and the expansion of opportunistic taxa. Carbonate production and hypersaline facies characterize the marginal part of the basins. Hypersaline surface water triggered downwelling circulation and mixing of water masses. Decreased abundance or extinction of K-specialists during each cold interval accelerated their speciation in the subsequent warm interval. Local tectonic events led to discordances between local and global sea-level changes (tectonically triggered uplift or subsidence or to local salt formation (in the rain shadows of newly-created mountains.

  8. Interception of residual nitrate from a calcareous alluvial soil profile on the North China Plain by deep-rooted crops: A 15N tracer study

    International Nuclear Information System (INIS)

    Ju, X.T.; Gao, Q.; Christie, P.; Zhang, F.S.

    2007-01-01

    15 N-labeled nitrate was injected into different depths of an alluvial calcareous soil profile on the North China Plain. Subsequent movement of NO 3 - N and its recovery by deep-rooted maize (Zea mays L.) and shallow-rooted eggplant (Solanum melongena L.) were studied. Under conventional water and nutrient management the mean recoveries of 15 N-labeled nitrate from K 15 NO 3 injected at depths 15, 45, and 75 cm were 22.4, 13.8, and 7.8% by maize and 7.9, 4.9, and 2.7% by eggplant. The recovery rate by maize at each soil depth was significantly higher than by eggplant. The deeper the injection of nitrate the smaller the distance of its downward movement and this corresponded with the movement of soil water during crop growth. Deeper rooting crops with high root length density and high water consumption may therefore be grown to utilize high concentrations of residual nitrate in the subsoil from previous intensive cropping and to protect the environment. - Deep-rooted crops have a greater capacity than shallow-rooted crops to intercept residual nitrate from the subsoil and restrict its movement down to the shallow groundwater

  9. Calcareous nannofossil evidence for Marine Isotope Stage 31 (1 Ma) in the AND-1B Core, ANDRILL McMurdo Ice Shelf Project (Antarctica).

    Science.gov (United States)

    Villa, G.; Persico, D.; Wise, S. W.; Gadaleta, A.

    2009-04-01

    During the austral summer 2006 the ANDRILL Program recovered a 1285 m-long succession of cyclic glacimarine sediments from the McMurdo Ice Shelf (MIS). The aim of the MIS Project was to obtain continuous Neogene (c. 0-10 Ma) glacial, glacimarine, volcanic, and biogenic sediments that have accumulated in the region of the McMurdo Ice Shelf (Ross Sea) nourished by ice flowing from East Antarctic Ice Sheet (EAIS) outlet glaciers in the Transantarctic Mountains (TAM). The MIS AND-1B drill core represents the longest and most complete (98% recovery) geological record from the Antarctic continental margin to date, and will provide a key reference record of climate and ice-sheet variability through the Late Neogene; detailed investigations of this record will contribute for improving our knowledge of Antarctica's influence on global climate. Preliminary on-ice analysis of the smear slides of the Andrill core revealed calcareous microfossils (dinoflagellates, calciosponge spicula and small foraminifera) occurring with variable concentrations. The presence of thoracosphaerid fragments in the smear slides of the first 600 mbsf (Quaternary), probably belong to the species Thoracosphaera saxea (Stradner 1961), and Thoracosphaera heimi (Kamptner, 1941) and other, potentially undescribed species (Villa & Wise 1998), suggests either a peculiar adaptation to this environment, due to their ability to develop cysts or warmer conditions at the time of their deposition, or a combination of both. However, they represent an additional element to use with the other proxies for inferring palaeoenvironmental conditions of the core. Subsequent shore-based analyses of 100 samples from 86-96 mbsf revealed for the first time the presence of Pleistocene coccolithophorids at these high southern latitudes (77° S), including: Coccolithus pelagicus, small Gephyrocapsa, Reticulofenestra asanoi, Pseudoemiliania lacunosa, Dictyoccocites productus, Reticulofenestra sp., Reticulofenestra minutula

  10. Phases and rates of iron and magnetism changes during paddy soil development on calcareous marine sediment and acid Quaternary red-clay.

    Science.gov (United States)

    Huang, Laiming; Jia, Xiaoxu; Shao, Ming'an; Chen, Liumei; Han, Guangzhong; Zhang, Ganlin

    2018-01-11

    Dynamic changes in Fe oxides and magnetic properties during natural pedogenesis are well documented, but variations and controls of Fe and magnetism changes during anthropedogenesis of paddy soils strongly affected by human activities remain poorly understood. We investigated temporal changes in different Fe pools and magnetic parameters in soil profiles from two contrasting paddy soil chronosequences developed on calcareous marine sediment and acid Quaternary red clay in Southern China to understand the directions, phases and rates of Fe and magnetism evolution in Anthrosols. Results showed that paddy soil evolution under the influence of artificial submergence and drainage caused changes in soil moisture regimes and redox conditions with both time and depth that controlled Fe transport and redistribution, leading to increasing profile differentiation of Fe oxides, rapid decrease of magnetic parameters, and formation of diagnostic horizons and features, irrespective of the different parent materials. However, the initial parent material characteristics (pH, Fe content and composition, weathering degree and landscape positions) exerted a strong influence on the rates and trajectories of Fe oxides evolution as well as the phases and rates of magnetism changes. This influence diminished with time as prolonged rice cultivation drove paddy soil evolving to common pedogenic features.

  11. The effect of buffering dairy cow diets with limestone, calcareous marine algae, or sodium bicarbonate on ruminal pH profiles, production responses, and rumen fermentation.

    Science.gov (United States)

    Cruywagen, C W; Taylor, S; Beya, M M; Calitz, T

    2015-08-01

    Six ruminally cannulated Holstein cows were used to evaluate the effect of 2 dietary buffers on rumen pH, milk production, milk composition, and rumen fermentation parameters. A high concentrate total mixed ration [35.2% forage dry matter (DM)], formulated to be potentially acidotic, was used to construct 3 dietary treatments in which calcareous marine algae (calcified remains of the seaweed Lithothamnium calcareum) was compared with limestone (control) and sodium bicarbonate plus limestone. One basal diet was formulated and the treatment diets contained either 0.4% of dietary DM as Acid Buf, a calcified marine algae product (AB treatment), or 0.8% of dietary DM as sodium bicarbonate and 0.37% as limestone (BC treatment), or 0.35% of dietary DM as limestone [control (CON) treatment]. Cows were randomly allocated to treatments according to a double 3×3 Latin square design, with 3 treatments and 3 periods. The total experimental period was 66 d during which each cow received each treatment for a period of 15 d before the data collection period of 7 d. Rumen fluid was collected to determine volatile fatty acids, lactic acid, and ammonia concentrations. Rumen pH was monitored every 10min for 2 consecutive days using a portable data logging system fitted with in-dwelling electrodes. Milk samples were analyzed for solid and mineral contents. The effect of treatment on acidity was clearly visible, especially from the period from midday to midnight when rumen pH dropped below 5.5 for a longer period of time (13 h) in the CON treatment than in the BC (8.7 h) and AB (4 h) treatments. Daily milk, 4% fat-corrected milk, and energy-corrected milk yields differed among treatments, with AB being the highest, followed by BC and CON. Both buffers increased milk fat content. Treatment had no effect on milk protein content, but protein yield was increased in the AB treatment. Total rumen volatile fatty acids and acetate concentrations were higher and propionate was lower in the AB

  12. Carbon and nitrogen uptake of calcareous benthic foraminifera along a depth-related oxygen gradient in the OMZ of the Arabian Sea

    Directory of Open Access Journals (Sweden)

    Annekatrin Julie Enge

    2016-02-01

    Full Text Available Foraminifera are an important faunal element of the benthos in oxygen-depleted settings such as Oxygen Minimum Zones (OMZs where they can play a relevant role in the processing of phytodetritus. We investigated the uptake of phytodetritus (labeled with 13C and 15N by cal-careous foraminifera in the 0-1 cm sediment horizon under different oxygen concentrations within the OMZ in the eastern Arabian Sea. The in situ tracer experiments were carried out along a depth transect on the Indian margin over a period of 4 to 10 days. The uptake of phy-todetrital carbon within 4 days by all investigated species shows that phytodetritus is a rele-vant food source for foraminifera in OMZ sediments. The decrease of total carbon uptake from 540 to 1100 m suggests a higher demand for carbon by species in the low-oxygen core region of the OMZ or less food competition with macrofauna. Especially Uvigerinids showed high uptake of phytodetrital carbon at the lowest oxygenated site. Variation in the ratio of phytodetrital carbon to nitrogen between species and sites indicates that foraminiferal carbon and nitrogen use can be decoupled and different nutritional demands are found between spe-cies. Lower ratio of phytodetrital carbon and nitrogen at 540 m could hint for greater demand or storage of food-based nitrogen, ingestion or hosting of bacteria under almost anoxic condi-tions. Shifts in the foraminiferal assemblage structure (controlled by oxygen or food availabil-ity and in the presence of other benthic organisms account for observed changes in the pro-cessing of phytodetritus in the different OMZ habitats. Foraminifera dominate the short-term processing of phytodetritus in the OMZ core but are less important in the lower OMZ bounda-ry region of the Indian margin as biological interactions and species distribution of foraminif-era change with depth and oxygen levels.

  13. Impact of Humic Acid on Yield and Quality of Sugar Beet (Beta vulgaris L. Grown on Calcareous Soil

    Directory of Open Access Journals (Sweden)

    Ghorbanali RASSAM

    2015-09-01

    Full Text Available A field experiment was performed to determine the effects of using humic acid with irrigation on quantitative and qualitative yield traits of sugar beet grown on calcareous soils in Esfaraen, located in the North-East of Iran. Treatments consisted of three levels of humic acid concentration (zero or control, 2.5 and 5 L ha-1 and the number of applications (once 45 days after planting; twice, 45 and 75 days after planting; three times, respectively 45, 75 and 105 days after planting. The effect of the two experimental factors on sugar beet yield traits such as the content of sucrose, refined sugar, molasses forming substances, root yield and refined sugar yield were evaluated. The results proved the existence of a significant interaction between humic acid concentration and the number of applications on all parameters under study. The application of humic acid caused a significant increase of sucrose, refined sugar, root yield and refined sugar yield and a reduction in molasses forming substances content, compared to the control. The increased amount of sucrose and refined sugar content in all applications in concentration of 2.5 L ha-1 humic acid was more than with 5 L ha-1. Similarly, the content of molasses forming substances showed more reduction in 2.5 L ha-1 than in 5 L ha-1 treatment. However, the results revealed that the highest root yield and refined sugar yield, as the main qualitative and quantitative parameters of sugar beet yield, were achieved by three times application of 5 L ha-1 that had 24 and 37% increase compared to control.

  14. Potential of Brassic rapa, Cannabis sativa, Helianthus annuus and Zea mays for phytoextraction of heavy metals from calcareous dredged sediment derived soils.

    Science.gov (United States)

    Meers, E; Ruttens, A; Hopgood, M; Lesage, E; Tack, F M G

    2005-10-01

    Remediation of soil pollution is one of the many current environmental challenges. Anthropogenic activity has resulted in the contamination of extended areas of land, the remediation of which is both invasive and expensive by conventional means. Phytoextraction of heavy metals from contaminated soils has the prospect of being a more economic in situ alternative. In addition, phytoextraction targets ecotoxicologically the most relevant soil fraction of these metals, i.e. the bioavailable fraction. Greenhouse experiments were carried out to evaluate the potential of four high biomass crop species in their potential for phytoextraction of heavy metals, with or without with the use of soil amendments (EDTA or EDDS). A calcareous dredged sediment derived surface soil, with high organic matter and clay content and moderate levels of heavy metal pollution, was used in the experiments. No growth depression was observed in EDTA or EDDS treated pots in comparison to untreated controls. Metal accumulation was considered to be low for phytoextraction purposes, despite the use of chelating agents. The low observed shoot concentrations of heavy metals were attributed to the low phytoavailability of heavy metals in this particular soil substrate. The mobilising effects induced by EDTA in the soil were found to be too long-lived for application as a soil amendment in phytoextraction. Although EDDS was found to be more biodegradable, higher effect half lives were observed than reported in literature or observed in previous experiments. These findings caution against the use of any amendment, biodegradable or otherwise, without proper investigation of its effects and the longevity thereof.

  15. Variations of the natural isotopic composition (15N) of mineral nitrogen from calcareous soils, studied during incubation experiment and on the field

    International Nuclear Information System (INIS)

    Mariotti, A.; Guillemot, J.

    1980-01-01

    This study was intended to follow the variations of isotope composition of mineral nitrogen formed during incubation of calcareous soils (rendzine), humidity and temperature conditions approximating natural ones. We compared the isotope composition with that of mineral nitrogen formed in a lysimeter cut out from a natural soil with the same pedological features. During the incubation experiments, two steps were recognized. A step with production of nitrates and nitrites depleted in 15 N and a second step where the isotope composition leans towards an equilibrium value. During the first step, the 15 N depletion for the sum NO 3 + NO 2 correlates with a 15 N enrichment for ammonium. On the whole, the total mineral nitrogen isotope composition is approximately constant. This first step corresponds also to a great speed of nitrification, to the presence of nitrite and to a large evolution (production or use) of ammonium. On the contrary, nitrites have disappeared and ammonium is in dynamic equilibrium (constant concentration) when the delta 15 N of nitrates is stabilized. In another set of experiments, with the same conditions, small quantity of a nitrogen substrate (vegetal proteins or amino acids) easily mineralizable, was added to the soil: the 15 N depletion of NO 3 + NO 2 formed during the first step is much greater than with the mere soil. It is concluded that the initial step corresponds to the fast mineralization of a very labile organic component which could be, for the mere soil, the microbial biomass destroyed during air-drying of sample before incubations: this could correspond to the 'flush effect'. On the contrary, the step when nitrates becomes constant could correspond to the mineralization (slower and more regular) of an another organic pool, perhaps part of humified organic matter [fr

  16. The Effect of Vermicompost on Reducing the Adverse Effects of Water Stress on Growth and Chemical Composition of Corn in a Calcareous Soil

    Directory of Open Access Journals (Sweden)

    leila zare

    2017-01-01

    Full Text Available Introduction: Vermicompost is one of the important bio-fertilizer which is the product of the process of composting different organic wastes such as manures and crop residues using different earthworms. Vermicomposts, especially those are derived from animal wastes,contain the large amounts of nutrients compaired with the composts prepared from crop residues. Vermicomposts contain plant available form of nutrients such as nitrate nitrogen, exchangeable phosphorus and potassium, calcium and magnesium. Nowadays, the use of vermicompost in sustainable agriculture to improve the growth and quality of fruits and crops is very common. Drought occurs when the amount of moisture in soil and water resources and rainfall is less than what plants need for normal growth and function. Two thirds of farm lands in Iran have been located in arid and semi-arid regions with annual rainfall less than150 mm that has been distributed irregularly and unpredictable during growth season imposing water stress in most crops. It indicates the importance of water management and proposing different strategies for mitigating detrimental effect of water stress in croplands. Due to the fact that crops nutrient management under drought and water stress using organic fertilizers is an effective method in reaching to high yields in sustainable agriculture, the objective of the present study was to investigate the influence of vermicompost application on reducing the adverse effects of water stress on the growth and chemical composition of corn in a calcareous soil. Materials and Methods: In order to study the influence of water stress and application of vermicompost on corn dry matter yield and nutrients concentration of corn shoot, a greenhouse factorial experiment (4×3 in completely randomized design with three replications was conducted in college of agriculture, Shiraz university, Shiraz, Iran. The factors consisted of four vermicompost levels (0, 10, 20 and30g kg-1soil

  17. Efficiency of a new strategy involving a new class of natural hetero-ligand iron(III) chelates (Fe(III)-NHL) to improve fruit tree growth in alkaline/calcareous soils.

    Science.gov (United States)

    Fuentes, Marta; Ortuño, María F; Pérez-Sarmiento, Francisco; Bacaicoa, Eva; Baigorri, Roberto; Conejero, Wenceslao; Torrecillas, Arturo; García-Mina, José M

    2012-12-01

    Iron (Fe) chlorosis is a serious problem affecting the yield and quality of numerous crops and fruit trees cultivated in alkaline/calcareous soils. This paper describes the efficiency of a new class of natural hetero-ligand Fe(III) chelates (Fe-NHL) to provide available Fe for chlorotic lemon trees grown in alkaline/calcareous soils. These chelates involve the participation in the reaction system of a partially humified lignin-based natural polymer and citric acid. First results showed that Fe-NHL was adsorbed on the soil matrix while maintaining available Fe for plants in alkaline/calcareous solution. The effects of using three different sources as Fe fertilisers were also compared: two Fe-NHL formulations (NHL1, containing 100% of Fe as Fe-NHL, and NHL2, containing 80% of Fe as Fe-NHL and 20% of Fe as Fe-ethylenediamine-N,N'-bis-(o-hydroxyphenylacetic) acid (Fe-EDDHA)) and Fe-EDDHA. Both Fe-NHL formulations increased fruit yield without negative effects on fruit quality in comparison with Fe-EDDHA. In the absence of the Fe-starter fraction (NHL1), trees seemed to optimise Fe assimilation and translocation from Fe-NHL, directing it to those parts of the plant more involved in development. The field assays confirmed that Fe-NHL-based fertilisers are able to provide Fe to chlorotic trees, with results comparable to Fe-EDDHA. Besides, this would imply a more sustainable and less expensive remediation than synthetic chelates. Copyright © 2012 Society of Chemical Industry.

  18. Two look-alike dasycladalean algae: Clypeina isabellae masse, Bucur, Virgone & Delmasso, 1999 from the Berriasian of Sardinia (Italy and Clypeina loferensis sp. N. from the upper Jurassic of the Northern Calcareous Alps (Austria

    Directory of Open Access Journals (Sweden)

    Schlagintweit Felix

    2009-01-01

    Full Text Available New material from the Berriasian of eastern Sardinia, Italy, and from the NW of Sardinia published by PECORINI in 1972 as 'Clypeina sp. A', allows a better characterization and an emended diagnosis of Clypeina isabellae MASSE et al., 1999 from the Berriasian of SW France. Another morphologically somehow similar Clypeina species from the Upper Jurassic of the Northern Calcareous Alps of Austria is described as Clypeina loferensis n. sp. Remarks on the genera Clypeina MICHELIN and Hamulusella ELLIOTT, a Clypeina-type dasycladalean alga with proximal bulged laterals, and Clypeina jurassica-sulcata are also provided.

  19. Timing of Indonesian Gateway Restriction Between 4.0 and 2.8 Ma and its Impact on Indian Ocean Surface Waters Based on Calcareous Nannoplankton Assemblages

    Science.gov (United States)

    Auer, G.; De Vleeschouwer, D.; Groeneveld, J.; Bogus, K.; Henderiks, J.; Castañeda, I. S.; Expedition 356 Scientists, I.

    2017-12-01

    The Early Pliocene is characterized by a fundamental reorganization of Earth's climate. In particular, the ongoing constriction of the Indonesian Gateway (IG) around 4.0 - 3.0 Ma is commonly evoked cause for these climatic changes (Christensen et al., 2017; De Schepper et al., 2014; Karas et al., 2009; 2017). The constriction of the IG, caused by the northward movement of Australia and related uplift of Indonesia, had major effects on global climate and may have contributed to Northern Hemisphere cooling via complex atmospheric and oceanographic teleconnections. Untangling the exact timing of IG constriction is thus critical for resolving the mechanisms driving Earth's climatic evolution during the Pliocene. Here we present high-resolution reconstructions of surface water conditions and IG connectivity using calcareous nannoplankton (CNP) assemblages between 4.0 and 2.8 Ma at Site U1463 (18°59'S, 117°37'E; IODP Expedition 356). Located on the Northwest Shelf (NWS) of Australia, the site lies directly in the path of the upper branch of the Leeuwin-Holloway current, making it an ideal location to study Pliocene IG dynamics and their influence on the eastern Indian Ocean. Using modern analogue based interpretation of CNP assemblages, in combination with an independent orbitally tuned age model, shows a change in surface water conditions along the NWS 3.8 Ma recognizable by a decrease in tropical taxa like Umbilicosphaera sibogae and Sphenolithus spp. Subsequently, a shift from Gephyrocapsa sp. to Reticulofenestra sp. dominated CNP assemblages and the increase of mesotrophic CNP taxa (e.g. Umbilicosphaera jafari; Helicosphaera spp.), suggests that warm, stratified, oligotrophic (i.e. tropical) waters were replaced by cooler, more turbulent, and less saline waters by 3.8 - 3.6 Ma. We relate this switch in dominant water masses to changes in IG geometry delivering relatively cooler and fresher waters from northern Pacific sources to the NWS. The abundance of

  20. Integrated management in calcareous soils

    International Nuclear Information System (INIS)

    Castilla, Luis A; Salive, A

    2001-01-01

    Rice growing is developed in different kinds of soils, and some of the have high bases saturation, especially calcium and magnesium, as well as medium to high carbonate contents. This causes negative effects in the development and growth of the rice plant. As a consequence, several researching actions have been under-taken, and they are aimed at becoming this problem in economically manageable. Among the strategies we have, some of them are as follows: evaluating rice varieties presenting tolerance to these soils; using inorganic fertilizers looking for a response to elements, sources, dose and application times; evaluating organic fertilizers, mainly the green ones; using amendments, and physical soil management. According to the results, we have the fertilization response with major and minor elements and with the statistical differences at a 0.05% level. A response was found with elements such as zinc, copper, boron, iron, phosphorus and potassium. However, the efficiency of these elements depends on the addition of amendments as sulfur, the use of green fertilizers and farming systems that eliminate the superficial compaction of these soils, besides the use of varieties which are more tolerant to alkalinity, just like Fedearroz-50

  1. Theoretical and experimental study of the bio-geochemical behaviour of americium 241 in simplified rhizosphere conditions. Application to a calcareous agricultural soil

    International Nuclear Information System (INIS)

    Perrier, T.

    2004-06-01

    Americium 241, is one of the most radio-toxic contaminant produced during the nuclear fuel cycle. It can be found in all environmental compartments, in particular the soils. The main goals of this study are to identify, quantify and model the effect of the main factors controlling the mobility of 241 Am in the rhizosphere and the agricultural soils. The physico-chemical parameters of the soil and of the soil solution, the potential role of microorganisms on the sorption-desorption processes, and the speciation of americium in solution have been more particularly studied. 241 Am remobilization has been studied at the laboratory using leaching experiments performed in controlled conditions on reworked calcareous soils artificially contaminated with 241 Am. The soil samples have been washed out in different hydrodynamic conditions by solutions with various compositions. The eluted solution has been analyzed (pH, conductivity, ionic composition, Fe tot , organic acids, 241 Am) and its bacterial biomass content too. The overall results indicate that 241 Am remobilization is contrasted and strongly linked with the condition under study (pH, ionic strength, glucose and/or citrate concentration). Therefore, a solution in equilibrium with the soil or containing small exudate concentrations (10 -4 M) re-mobilizes only a very small part of the americium fixed on the solid phase. The desorption of 241 Am corresponds to a solid/liquid coefficient of partition (K d ) of about 10 5 L.kg -1 . A significant addition of glucose induces an important dissolution of soil carbonates by the indirect action of microorganisms, but does not significantly favor the 241 Am remobilization. On the other hand, the presence of strong citrate concentrations (≥ 10 -2 M) allows 300 to 10000 time greater re-mobilizations by the complexing of 241 Am released after the dissolution of the carrying phases. Finally, the colloidal transport of 241 Am has been systematically observed in a limited but

  2. Discovery of a landscape-wide drape of late-glacial aeolian silt in the western Northern Calcareous Alps (Austria): First results and implications

    Science.gov (United States)

    Gild, Charlotte; Geitner, Clemens; Sanders, Diethard

    2018-01-01

    Aeolian deposits record palaeoenvironmental conditions and may coin soil properties. Whereas periglacial loess is extensively investigated for 200 years, the study of the intramontane wind-blown deposits of the Alps has just stuttered along. Herein, we describe a drape of polymictic siliciclastic silt interpreted as an aeolian deposit that veneers extensive areas in the western Northern Calcareous Alps (NCA), from kames terraces near valley floors up to last-glacial nunataks. The NCA - part of the Eastern Alps mountain range - consist mainly of Triassic carbonate rocks; these are overlain by deposits of the Last Glacial Maximum (LGM) and its deglacial-paraglacial aftermath (e.g., glacial tills, fluvio-lacustrine successions, alluvial fans, scree slopes) - and a regional drape of polymictic silt newly described herein. The drape is typically a few decimeters in thickness and slightly modified by soil formation; it consists mainly of well-sorted silt of quartz, feldspars, phyllosilicates (muscovite, chlorite, biotite), amphiboles and, rarely, calcite or dolomite. The drape is unrelated to the substrate: it overlies carbonate bedrock and - in lateral continuity - abandoned deposystems such as colluvial slopes of redeposited till, kames, alluvial fans, scree slopes, and rock avalanche deposits. The drape was spotted from near the present valley floors up to LGM nunataks, over a vertical range of some 2000 m; it is also present in catchments of the NCA that were not overridden by far-travelled ice streams and that lack metamorphic rock fragments. Two OSL quartz ages of the drape from two distinct locations (18.77 ± 1.55 ka; 17.81 ± 1.68 ka) fall into the early Alpine late-glacial interval shortly after the collapse of pleniglacial ice streams; this fits with geological and geomorphological evidence, respectively, that the drape should be of early late-glacial age, and that it accumulated during a specific interval of time. In the NCA, localized minor deposition of

  3. Effect of Plant Growth Promoting Rhizobacteria on the Concentration and Uptake of Macro Nutrients by Corn in a Cd-contaminated Calcareous Soil under Drought Stress

    Directory of Open Access Journals (Sweden)

    shahrzad karami

    2017-02-01

    Full Text Available Introduction: Heavy metals such as cadmium (Cd are found naturally in soils, but their amount can be changed by human activities. The study of the uptake and accumulation of heavy metals by plants is done in order to prevent their threats on human and animal’s health.Cadmium is a toxic element for living organisms. Cadmium competes with many of nutrients to be absorbed by the plant and interferes with their biological roles. Water stress affects the cell structure and the food is diverted from its normal metabolic pathway. It also reduces the availability and uptake of nutrients by the plant. One reason for the reduction of plant growth under drought stress is the accumulation of ethylene in plants. There are ways to mitigate the negative effects of drought stress that one of which is the use of Plant Growth Promoting Rhizobacteria(PGPRs to increasing the availability of nutrients. Soil beneficial bacteria play an important role in the biological cycles and have been used to increase plant health and soil fertility over the past few decades.The aim of this study was to investigate theeffect of PGPRson the concentration and uptake of macro nutrients by corn in a Cd-contaminated calcareous soil under drought stress. Materials and Methods: A greenhouse factorial experiment was conducted in a completely randomized design with three replications. The treatments were two levels of bacteria (with and without bacteria, four levels of Cd (5, 10, 20, and 40 mg kg-1, and three levels of drought stress (without stress, 80, and 65% of field capacity. The pots were filled with 3 kg of treated soil. Cd was treated as its sulfate salt in amounts of 5, 10, 20, and 40 mg kg-1. The soil was mixed uniformly with 150 mg N kg-1 as urea, 20 mg P kg-1 as Ca (H2PO42, 5 mg Fe kg-1 as Fe-EDDHA and 10, 10 and 2.5 mg Zn, Mn and Cu kg-1, respectively as their sulfate salt in order to meet plant needs for these nutrients. Six seeds of Zea mays (var. HIDO were planted at

  4. Greater rate of cephalic screw mobilisation following proximal femoral nailing in hip fractures with a tip-apex distance (TAD) and a calcar referenced TAD greater than 25 mm.

    Science.gov (United States)

    Aicale, Rocco; Maffulli, Nicola

    2018-05-02

    To ascertain whether the tip-apex distance (TAD), calcar referenced TAD (CalTAD), and the sum of both (TADcalTAD) are predictive measurements of mobilisation of the cephalic screw in patients with trochanteric hip fractures. Between 2014 and 2015, 68 patients (mean age 86 years, 45 females, 23 males) with a trochanteric hip fracture underwent intramedullary nailing. The TAD and CalTAD were measured, and for each parameter, we calculated sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV). There is evidence of a statistically significant association between a TAD and CalTAD greater than 25 mm and a TADcalTAD greater than 50 mm and mobilisation of the cephalic screw. All measurements have similar sensitivity, but the TAD presents the highest specificity (p TAD and CalTAD less than 25 mm and a TADcalTAD less than 50 mm when using intramedullary fixation.

  5. Sr90 determination in calcareous water

    International Nuclear Information System (INIS)

    Cohen, P.; Pardo, G.; Wormser, G.

    1958-01-01

    The Straub method (ref. 2) for determination of radioactive strontium in water containing calcium is valid within very wide limits, and particularly in the case of residual water from the chemical purification treatment of the radioactive liquid effluent at the C.E.N. Saclay. (author) [fr

  6. Properties and durability assessment of glauconitic sandstone: A case study on Zamel sandstone from Bohemian Cretaceous Basin (Czech Republic)

    Czech Academy of Sciences Publication Activity Database

    Martinec, Petr; Vavro, M.; Ščučka, Jiří; Mašláň, M.

    2010-01-01

    Roč. 115, 3/4 (2010), s. 175-181 ISSN 0013-7952 R&D Projects: GA ČR GP101/07/P512; GA ČR(CZ) GA103/07/1662 Institutional research plan: CEZ:AV0Z30860518 Keywords : building stone * sandstone * physical properties Subject RIV: DB - Geology ; Mineralogy Impact factor: 1.442, year: 2010 http://www.sciencedirect.com/science

  7. Nanofósiles calcáreos paleógenos y biostratigrafía para dos pozos en el este de la Cuenca Austral, Patagonia, Argentina Paleogene calcareous nannofossil biostratigraphy for two boreholes in the eastern Austral Basin, Patagonia, Argentina

    Directory of Open Access Journals (Sweden)

    Juan Pablo Pérez Panera

    2013-01-01

    Full Text Available Calcareous nannofossils from two boreholes (Campo Bola and Sur Río Chico in the subsurface of eastern Austral Basin, Santa Cruz Province, Argentina, allowed the identification of Early to Middle Paleocene, Early to Middle Eocene and Late Eocene to Early Oligocene assemblages. These assemblages match the formations logged in the boreholes Campo Bola, Man Aike and Río Leona respectively, and represent three paleogene sedimentary cycles within the basin. These results permitted the reinterpretation of previous data from an adjacent borehole (Cerro Redondo. The southern boreholes (Cerro Redondo and Sur Río Chico yield an Early to Middle Paleocene calcareous nannofossil assemblage and an almost continuous record of nannofossils from Early Eocene to Early Oligocene. A discontinuity is interpreted by the absence of Late Paleocene assemblages. The northern borehole (Campo Bola yield only late Early Eocene to Early Oligocene assemblages. The data also indicates that the Paleogene beds unconformably overlie Upper Cretaceous strata.El estudio de los nanofósiles calcáreos recuperados en muestras de subsuelo de dos pozos de exploración (Campo Bola y Sur Río Chico en el este de la Cuenca Austral, provincia de Santa Cruz, Argentina, permitió reconocer asociaciones del Paleoceno Temprano a Medio, Eoceno Temprano a Medio y Eoceno Tardío a Oligoceno Temprano. Estas asociaciones son coincidentes con las formaciones atravesadas en los sondeos hechos en Campo Bola, Man Aike y Río Leona, respectivamente, y representan tres ciclos sedimentarios paleógenos dentro de la cuenca. Estos resultados permitieron la reinterpretación de datos previos de un pozo adyacente (Cerro Redondo. Los pozos ubicados al sur (Cerro Redondo y Sur Río Chico contienen asociaciones de nanofósiles calcáreos del Paleoceno Temprano a Medio y un registro prácticamente continuo de nanofósiles del Eoceno Temprano al Oligoceno Temprano. Se interpreta una discontinuidad por ausencia de

  8. Analysis of reworked sediments as a basis of the Palaeogene-Neogene palaeogeography reinterpretation: Case study of the Roztocze region (SE Poland)

    Science.gov (United States)

    Margielewski, Włodzimierz; Jankowski, Leszek; Krąpiec, Marek; Garecka, Małgorzata; Hałas, Stanisław; Urban, Jan

    2017-05-01

    Radiometric K/Ar dating of glauconite and nanno- and micropaleontologic analyses of calcareous nannoplankton, foraminifers and dinoflagellates isolated from the Miocene rocks in the Polish part of the Roztocze region, a northeastern part of the fore-bulge of the Carpathian Foreland Basin System - CFBS), SE Poland, reveal that these strata contain numerous microfossils and glauconite grains of the Upper Eocene and Lower Oligocene age. Such occurrences clearly indicate that these materials were redeposited from the Upper Eocene and Lower Oligocene marine rocks that must have originally covered most of the Roztocze and the surrounding area. It is therefore proposed herein that the geographical extent of the boreal, epi-continental basin during the Eocene-Oligocene was much greater than previously considered. Moreover, it appears that this basin was connected with the back-bulge zone of the warm Carpathian Basin (originally a northern part of the Tethys Basin which since Eocene/Oligocene boundary remained isolated as the Paratethys Basin). Hence, it is unlikely that the Roztocze region was uplifted during the Palaeogene as part of the Meta-Carpathian Swell, as it was earlied hypothesized. Instead, the Roztocze Swell formed during the Sarmatian, in the last stage of the development of the fore-bulge structure in the foreland of the up-thrust Carpathian orogenic belt. Multiple redeposition of sediments is the reason that the absolute dating (K/Ar) of glauconite, as well as incomprehensive palaeontological analysis could result in erroneous stratigraphic and palaeogeographic interpretations.

  9. Mineralogía de arcillas y nanofósiles calcáreos de las formaciones Jagüel y Roca en el sector oriental del lago Pellegrini, Cuenca Neuquina, República Argentina Clay mineralogy and calcareous nannofossils from Jagüel and Roca formations in the eastern sector of Pellegrini Lake, Neuquen Basin, República Argentina

    Directory of Open Access Journals (Sweden)

    Telma Musso

    2012-09-01

    hacia posiciones más altas del Daniano, lo cual podría indicar un clima cálido y más húmedo en este intervalo, que tendería a condiciones menos húmedas y estacionales hacia el Daniano tardío. Las asociaciones de nanofósiles calcáreos maastrichtianos sugerirían la existencia de ambientes oligotróficos con buena estratificación de la capa fótica, aunque en algunos niveles la nanoflora es abundante y con menor riqueza específica, lo que indica condiciones marinas más restringidas.This study presents new mineralogical, sedimentologi-cal, and micropaleontological data from the Jagüel (Late Maastrichtian-Early Danian and Roca (Danian formations, located in the eastern sector of Pellegrini Lake, Río Negro province, República Argentina. According to the physical characteristics and the age of the sediments that conform these formations, two siliciclastic lithofacies and a carbonate one were recognized, they are named: Maastrichtian grayish yellow calcareous mudstones, Danian olive gray calcareous mudstones, and Danian carbonates. The rocks which constitutes siliciclastic lithofacies were classified as allochemical mudstones and the mineralogy is characterized by high proportions of clay minerals and, to a lesser extent, calcite. The clay mineral association is dominated by a random (R0 I/S mixed-layers (70-90% Sm accompanied by lower proportions of illite and kaolinite. The mineralogy and the microfabric of the mudstones reflect that these sediments have not been affected significantly by diagenesis. Clay minerals would be of detrital origin and the predominance of the highly smectitic I/S along all sections would be associated with an active volcanism coming from the western magmatic arc, located in the Neuquén Basin during the Late Cretaceous and Paleocene. Micropalaeontological analyses confirmed the presence of Cretaceous-Paleogene transition in the Jagüel Formation beds. The calcareous nannofossils allowed to relate changes in the the mineralogical

  10. Multivariate analysis of calcareous nanno fossils and stable isotopic ({delta}{sup 18}O and {delta}{sup 13}C) in the upper Campanian - lower Maastrichtian of the Campos Basin, Brazil; Analise multivariada em nanofosseis calcarios e isotopos estaveis ({delta}{sup 18}O e {delta}{sup 13}C) do Campaniano superior - Maastrichtiano inferior na Bacia de Campos

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, Luiz Carlos Veiga de [PETROBRAS, Rio de Janeiro, RJ (Brazil). Centro de Pesquisas. Gerencia de Bioestratigrafia e Paleoecologia]. E-mail: lcveiga@petrobras.com.br; Rodrigues, Rene; Lemos, Valesca Brasil

    2005-05-01

    Qualitative analysis in calcareous nanno fossils is a powerful tool for bio stratigraphic uses, principally in identification of bio zones and determination of relative age. But quantitative studies must be applied for pale oceanographic applications and high resolution bio stratigraphy. In order to better understand the relationships between the different species of nanno fossils, new methodologies and non-traditional correlation tools were tested on a 18 m upper Campanian - lower Maastrichtian core from Campos Basin. Multiple regression helped to determine the best counting method. Watznaueria barnesae and Micula decussata dominate the fossil assemblage and have inverse abundances to each other. Both were opportunist species in competition for nutrients. Q mode factorial analysis (57 samples, 19 variables) was applied to the same core and shows that two factors explain 99.2% of the total variance of the micro fossil assemblage. The first factor represents 83.6% and the second factor only 15.6% of the total variance. The former is associated with Watznaueria barnesae, Cribrosphaerella ehrenbergii and Stradneria crenulata, which represent the original population of nano plankton. The latter factor is associated with Micula decussata, which is believed to represent the effect of solution at the sediment water interface. Both factors were used to develop a dissolution-sea level curve for nanno fossils. When combined with oxygen and carbon isotopes, this curve clearly shows that higher dissolution occurred during the late Campanian - early Maastrichtian time when {delta}{sup 18}O, {delta}{sup 13} C and TOC all had lower values. These correlations indicate a strong link between high sea levels, high temperatures and lower amount of continental organic debris. (author)

  11. TAXONOMY OF VISEAN MARINE CALCAREOUS ALGAE, FERNIE, BRITISH COLUMBIA (CANADA

    Directory of Open Access Journals (Sweden)

    BERNARD MAMET

    2006-11-01

    Full Text Available Reports a diverse microflora from the Late Viséan Opal Member, Fernie, Rocky Mountains, Canada.  A shallow-water limestone level yields forty identifiable taxa of green and red algae associated with  microproblematica.  Four  species are new :  Cabrieropora opalae, Cribrokamaena ferniensis, Koninckopora pachytheca and Moravammina ? enigmatica.  Inferred sedimentation is open marine, in normal salinity, from the middle part of the euphotic zone, within the fair-weather wave zone.  A semi-restricted lagoon located nearby provides floated calcispheres.  The high diversity is due to the excellent preservation of the thalli which were protected by a thin early coating of bacterial micrite. 

  12. The biodegradability of EDDHA chelates under calcareous soil conditions

    NARCIS (Netherlands)

    Schenkeveld, W.D.C.; Hoffland, E.; Reichwein, A.M.; Temminghoff, E.J.M.; Riemsdijk, van W.H.

    2012-01-01

    FeEDDHA (iron (3 +) ethylenediamine-N,N'-bis(hydroxy phenyl acetic acid) products are commonly applied to mend or prevent Fe chlorosis in plants. In soil application, racemic and meso o,o-FeEDDHA are the effective components, while o,p-FeEDDHA tends to adsorb or react to o,p-CuEDDHA. Upon

  13. Yield performance of cowpea plant introductions grown in calcareous soils

    Science.gov (United States)

    Cowpea or Southernpea [Vigna unguiculata (L.) Walp.] is an important legume crop used as a feed for livestock, as a green vegetable and for consumption of its dry beans which provide 22-25% protein. The crop is very sensitive to alkaline soil conditions. When grown at a soil pH of 7.5 or higher, co...

  14. Seasonal patterns of periphyton nitrogen fixation in calcareous wetlands

    Science.gov (United States)

    Liao, X.; Inglett, P.

    2011-12-01

    Periphyton mats are an ecologically important component of the Everglades ecosystem and plays various vital ecological functions. However, nitrogen fixation of periphyton, has received little attention throughout much of the Everglades system. The objective of this study was to characterize the seasonal pattern of periphyton N2 fixation in the Hole-in-the-Donut (HID) of Florida Everglades, where farmed marl prairie wetlands have been restored through complete soil removal (CSR) to reduce nutrient levels. Two restored areas (i.e., cleared in 2000 and 2003) and a reference (natural and unfarmed) marl prairie wetland sites were selected in the HID. Seven times of sampling were performed across the wet and dry season during the 2010 and 2011. The annual fixed nitrogen was approximately 0.4gN m-2 yr-1 in the restored sites which was higher in the reference site (~0.2gN m-2 yr-1). All the three sites showed similar seasonal patterns of N2 fixation that is higher values were observed in the wet season; but the peak value was one month later in reference sits (i.e., September) comparing to the restored areas (i.e., July). The peak of periphyton AR rates in the 2000- and 2003-restored areas appeared in July (i.e., wet season) within the range of 20-79 nmols g-1dw h-1 and 31-53nmols g-1dw h-1, respectively. In contrast, the peak of reference site was observed in September with the range of 2-5 nmols g-1dw h-1. Stable N isotopic ratios (i.e., δ15N) also varied with time but didn't show consistent seasonal pattern as nitrogen fixation. N2 fixation positively correlated with periphyton total phosphorus (TP) and negatively correlated with total nitrogen and phosphorus molar ratios (TN:TP), indicating that N2 fixation would be a indicator of nutrient limitation. In general, δ15N was negatively correlated with nitrogenase activity but the correlation became weakened in the wet season, especially in the flooded July and September, which would be explained by other environmental factors and higher denitrification activities in that time.

  15. Living (stained calcareous benthic foraminifera from recent sediments off Concepción, central-southern Chile (~36° S Foraminíferos bentónicos calcáreos vivos (teñidos en sedimentos recientes de Concepción, Chile centro-sur (~36° S

    Directory of Open Access Journals (Sweden)

    RAÚL TAPIA

    2008-09-01

    Full Text Available This study examines onshore-offshore and vertical distribution of living (Rose Bengal stained benthic foraminifera (> 180 μm fraction from three sediment stations along a bathymetric transect off Concepción, Chile (station 18 = 88 m water depth, station 26 = 120 m, station 40 = 1,030 m, within and below the oxygen minimum zone. All cores were collected in austral winter. Calcareous foraminifera dominated the three stations. The species composition, living foraminifera density, and vertical distribution patterns within the sediment changed in accordance with bottom water dissolved oxygen concentration and food availability. Onshore-offshore pattern revealed overall highest living foraminiferal densities at shelf stations 18 and 26 where bottom water dissolved oxygen was lowest (~ 0.2 mL-1 and content in labile organic matter highest. Within the sediment, maximum relative abundances (50-60 % of living organisms were found in the 0-1 cm interval at the organic-rich and oxygen-poor shelf stations 18 and 26. In the well-oxygenated (2.7 mL-1 slope station 40, 70 % of living foraminifera were observed deeper than the first centimeter. The number of species and the contribution of the > 250 μm fraction to the total fauna larger than 180 μm increased offshore. Nonionella auris (d'Orbigny dominated at stations 18 and 26 while a more diverse foraminifera fauna was found at station 40. This study provides the first quantitative data on living benthic foraminifera in the area; seasonal and interannual changes are not addressed.Este estudio examina la distribución costa-océano y vertical de los foraminíferos bentónicos calcáreos (fracción > 180 im vivos (teñidos en tres estaciones a lo largo de un transecto batimétrico frente al área de Concepción, Chile (estación 18 = 88 m, estación 26 = 120 m, estación 40 = 1.030 m de profundidad, dentro y bajo la zona mínima de oxígeno. Todos los testigos de sedimento fueron recolectados durante el per

  16. Mapping Bedrock Topography using Electromagnetic Profiling ...

    African Journals Online (AJOL)

    Mapping Bedrock Topography using Electromagnetic Profiling. ... will be constructed The area under study is within the Abakaliki Shales Geologic Formation. ... micaceous sandstone; micaceous siltstone, sandy shales and shelly limestone.

  17. Traces of the heritage arising from the Macelj sandstone

    Science.gov (United States)

    Golež, Mateja

    2014-05-01

    The landscape of Southeast Slovenia and its stone heritage principally reveal itself through various Miocene sandstones. The most frequently found type on the borderline between Slovenia and Croatia, i.e. east of Rogatec, is the micaceous-quartz Macelj sandstone. This rock ranges in colour from greenish grey to bluish grey and yellowish, depending on the content of glauconite, which colours it green. In its composition, the rock is a heterogeneous mixture of grains of quartz, dolomite, muscovite, microcline, anorthite and glauconite. The average size of grains is 300μm. In cross-section, they are oblong, semi-rounded or round. The mechanical-physical and durability properties of the Macelj sandstone, which have been characterised pursuant to the applicable standards for natural stone, reveal that the rock exhibits poor resistance to active substances from the atmosphere, particularly in the presence of salt. In the surroundings of Rogatec, there are around 45 abandoned quarries of the Macelj sandstone, which are the result of the exploitation of this mineral resource from the 17th century on. The local quarrymen earned their bread until 1957, when the Kambrus quarry industry closed down. From the original use of this mineral resource as construction and decorative material, the useful value of the Macelj sandstone expanded during the development of the metals industry to the manufacture of large and small grindstones for the needs of the domestic and international market. Therefore, traces of quarrying can not only be seen in the disused quarries, but also in the rich architectural heritage of Rogatec and its surroundings, the stone furniture - from portals, window frames, wells, various troughs, pavements to stone walls - and other. The living quarrying heritage slowly passed into oblivion after World War II, although the analysis of the social image of the people residing in Rogatec and its surroundings revealed that there was an average of one stonemason in

  18. Role of a productive lake in carbon sequestration within a calcareous catchment

    International Nuclear Information System (INIS)

    Nõges, Peeter; Cremona, Fabien; Laas, Alo; Martma, Tõnu; Rõõm, Eva-Ingrid; Toming, Kaire; Viik, Malle; Vilbaste, Sirje; Nõges, Tiina

    2016-01-01

    For a long time, lakes were considered unimportant in the global carbon (C) cycle because of their small total area compared to the ocean. Over the last two decades, a number of studies have highlighted the important role of lakes in both sequestering atmospheric C and modifying the C flux from the catchment by degassing CO_2 and methane and burying calcite and organic matter in the sediment. Based on a full C mass balance, high frequency measurements of lake metabolism and stable isotope analysis of a large shallow eutrophic lake in Estonia, we assess the role alkaline lakes play in augmenting the strength of terrestrial carbonate weathering as a temporary CO_2 sink. We show that a large part of organic C buried in the sediments in this type of lakes originates from the catchment although a direct uptake from the atmosphere during periods of intensive phytoplankton growth in eutrophic conditions contributes to the carbon sink. - Highlights: • Terrestrial carbonate weathering is considered a temporary sink for CO_2_. • Alkaline lakes precipitate calcite reverting chemical weathering reactions. • Algal uptake increased δ"1"3C of dissolved inorganic C while passing through the lake. • 40–70% of sediment organic C originated from catchment alkalinity export. • Biological uptake of released CO_2 counteracts emissions from reversed weathering.

  19. Assessing different agricultural managements with the use of soil quality indices in a Mediteranean calcareous soil

    Science.gov (United States)

    Morugán-Coronado, Alicia; García-Orenes, Fuensanta; Mataix-Solera, Jorge; Arcenegui, Vicky; Cerdà, Artemi

    2013-04-01

    Soil erosion is a major problem in the Mediterranean region due to the arid conditions and torrential rainfalls, which contribute to the degradation of agricultural land. New strategies must be developed to reduce soil losses and recover or maintain soil functionality in order to achieve a sustainable agriculture. An experiment was designed to evaluate the effect of different agricultural management on soil properties and soil quality. Ten different treatments (contact herbicide, systemic herbicide, ploughing, Oat mulch non-plough, Oats mulch plough, leguminous plant, straw rice mulch, chipped pruned branches, residual-herbicide and agro geo-textile, and three control plots including no tillage or control and long agricultural abandonment (shrub on marls and shrub on limestone) were established in 'El Teularet experimental station' located in the Sierra de Enguera (Valencia, Spain). The soil is a Typic Xerorthent developed over Cretaceous marls in an old agricultural terrace. The agricultural management can modify the soil equilibrium and affect its quality. In this work two soil quality indices (models) developed by Zornoza et al. (2007) are used to evaluate the effects of the different agricultural management along 4 years. The models were developed studying different soil properties in undisturbed forest soils in SE Spain, and the relationships between soil parameters were established using multiple linear regressions. Model 1, that explained 92% of the variance in soil organic carbon (SOC) showed that the SOC can be calculated by the linear combination of 6 physical, chemical and biochemical properties (acid phosphatase, water holding capacity (WHC), electrical conductivity (EC), available phosphorus (P), cation exchange capacity (CEC) and aggregate stability (AS). Model 2 explains 89% of the SOC variance, which can be calculated by means of 7 chemical and biochemical properties (urease, phosphatase, and ß-glucosidase activities, pH, EC, P and CEC). We use the residual (difference between calculated SOC by models and real SOC, analyzed in laboratory) as soil quality indices. We consider higher soil quality when the residuals are closer to cero or inside confidence intervals of the models (95%). As expected, the application of the models indicates that in all the treatments and the control plots (shrub on marls and shrub on limestone), the residuals are out of the confidence intervals for the models, showing a disequilibrium among soil properties because these treatments have been submitted to a perturbation such as the agricultural use. However, it can be observed that the residuals in the last sampling in control plots and some of the treatments, the least aggressive with the soil, are lower and therefore the soil it seems to the soil properties is achieving to their equilibrium among them. These soils are: Shrub on limestone and shrub on marls, Chipped pruned branches and Oat mulch non-plough. These results are in agreement with García-Orenes et al. (2010), who showed that the addition of oat straw to soil can be considered an effective soil management, because it produced an important increase of the different fractions of organic carbon and microbial activity, that it will be translated into a rapid improvement of soil quality. The application of the herbicides studied produced a decrease in all the soil parameters; these practices are not recommendable for a sustainable agricultural system in semiarid Mediterranean agro-ecosystem. -García-Orenes, F., Guerrero, C., Roldán, A., Mataix-Solera, J., Cerdà, A. Campoy, M., Zornoza, R., Bárcenas, G., Caravaca, F., (2010). Soil microbial biomass and activity under different agricultural management systems in a semiarid Mediterranean agroecosystem. Soil & Tillage Research 109: 110-115. -Zornoza, R., Mataix-Solera, J., Guerrero, C., Arcenegui, V., Mayoral, A.M., Morales, J. Mataix-Beneyto, J., 2007. Soil properties under natural forest in the Alicante Province of Spain. Geoderma. 142, 334-341 Aknowledgements: The authors acknowledge the 'Teularet experimental station' staff for the collaboration.

  20. Bone regeneration of calvarial defect using marine calcareous-derived beta-tricalcium phosphate macrospheres

    Directory of Open Access Journals (Sweden)

    Joshua Chou

    2014-02-01

    Full Text Available The aim of this study was to examine the bone regeneration properties of beta-tricalcium phosphate hydrothermally converted from foraminifera carbonate exoskeleton in the repair of rat calvarial defect. These natural materials possess unique interconnected porous network with uniform pore size distribution, which can be potentially advantageous. In total, 20 adult male Wistar rats received full-thickness calvarial defect with a diameter of 5 mm. The rate of newly formed bone was measured radiologically by X-ray and micro-computed tomography and by histologic examination. After 2 weeks, the beta-tricalcium phosphate group exhibited full closure of the defect site, while control group remained unrestored at the end of the 6-week experimentation. It was observed that the newly regenerated bone thickened over the course of the experiment in the beta-tricalcium phosphate group. No soft tissue reaction was observed around the beta-tricalcium phosphate implant and the rats remained healthy. These results showed that repair of the calvarial defect can be achieved by biomimetic beta-tricalcium phosphate macrospheres, which hold potential for application as bone grafts for bone augmentation surgeries.

  1. New records of the rare calcareous sponge Paragrantia waguensis Hôzawa, 1940

    Science.gov (United States)

    Van Soest, Rob W.M.; Hoeksema, Bert W.; Reimer, James D.; De Voogd, Nicole J.

    2015-01-01

    Abstract Paragrantia waguensis Hôzawa is reported from coastal reefs of the island of Okinawa. This rare species was previously known only from Central Japan, Mie Prefecture. It has peculiar apopylar tetractine spicules, so far unique among Calcarea. We present in situ images of the species and a full description including SEM images of skeletal structure and spicule complement. The status of Paragrantia as a separate genus of the family Grantiidae distinct from Grantia Fleming is confirmed on the basis of a morphological and molecular comparison with the European type species of Grantia, Grantia compressa (Fabricius). PMID:26798302

  2. Parameters controlling fracturing distribution: example of an Upper Jurassic marly-calcareous formation (eastern Paris Basin)

    International Nuclear Information System (INIS)

    Andre, G.; Rebours, H.; Wileveau, Y.; Proudhon, B.

    2006-01-01

    Study of fractures along a 490-m vertical section of marl/limestone alternations in the Upper Jurassic (Meuse/Haute-Marne underground research laboratory-eastern Paris Basin) reveals their organization and the different states of palaeo-stress. Type and extension of tectonic structures seem to be controlled principally by lithology and secondary by depth. Also, it appears deviations of Alpine palaeo-stresses between Kimmeridgian and Oxfordian formations. These deviations are related to the presence of marl/limestone contacts. The vertical evolution of current horizontal maximum stress shows a similar behaviour, with deviations at the walls of Callovo-Oxfordian argilites. These results allow us to point out and to discuss the impact of lithology, rheology and depth on fracturing occurrence and distribution. Furthermore, this study suggests the role of Callovo-Oxfordian as a barrier for fracture development between the limestones of Dogger and Oxfordian formations. (authors)

  3. Simple, simultaneous gravimetric determination of calcite and dolomite in calcareous soils

    Science.gov (United States)

    Literature pertaining to determination of calcite and dolomite is not modern and describes slow methods that require expensive specialized apparatus. The objective of this paper was to describe a new method that requires no specialized equipment. Linear regressions and correlation coefficients for...

  4. The calcareous speleothems in the pseudokarst Jaskinia Slowianska-Drwali cave, Beskid Niski Mts., Poland

    Czech Academy of Sciences Publication Activity Database

    Urban, J.; Margielewski, W.; Žák, Karel; Hercman, H.; Sujka, G.; Mleczek, T.

    2007-01-01

    Roč. 63, č. 6 (2007), s. 119-128 ISSN 1643-9252 R&D Projects: GA ČR GA205/02/0449 Institutional research plan: CEZ:AV0Z30130516 Keywords : speleothems * pseudokarst * Carpathians Subject RIV: DB - Geology ; Mineralogy

  5. Komposisi Nutrisi Rumput Laut Calcareous Halimeda opuntia pada Lingkungan Perairan Indonesia

    Directory of Open Access Journals (Sweden)

    Nurhayati Nurhayati

    2017-06-01

    Full Text Available Halimeda opuntia merupakan rumput laut Chlorophyta berkapur yang memiliki kandungan nutrisi untuk pangan fungsional. Namun, pergeseran komposisi nutrisi dapat terjadi akibat perubahan lingkungan akibat limpasan nutrien dan bahan organik lainnya yang umum terjadi di perairan pesisir Indonesia. Penelitian ini bertujuan untuk melakukan identifikasi pergeseran kandungan nutrisi H. opuntia yang tumbuh di zona intertidal agar dapat digunakan sebagai dasar pemilihan lokasi pengambilan bahan baku H. opuntia untuk produk fungsional. Pengambilan sampel dilakukan di empat lokasi perairan di Indonesia, yaitu perairan Binuangeun (Banten, Lampung Selatan, Lombok Timur (Nusa Tenggara Barat dan Konawe Selatan (Sulawesi Tenggara. Karakteristik nutrisi dari rumput laut target meliputi kadar air, abu, protein, lemak, karbohidrat, dan serat kasar. Informasi lingkungan dari habitat sampel ditunjukkan melalui variabel kimia air yaitu DO, pH, salinitas, pCO2, kalsium aragonit, nitrogen anorganik terlarut, serta fosfat anorganik terlarut. Hasil analisis menunjukkan kondisi lingkungan eutrofik berpengaruh secara signifikan terhadap komposisi nutrisi H. opuntia. pH dan salinitas menjadi faktor determinan positif (R2 = 0,75 pada p<0,05 terhadap kadar karbohidrat, sementara nitrogen anorganik terlarut menjadi faktor determinan negatif terhadap kadar protein dan lemak (R2= 0,81 dan 0,61 pada p<0,05. Berdasarkan kandungan nutrisinya, maka H. opuntia yang diperoleh dari habitat alamiah merupakan bahan baku produk fungsional yang  lebih baik dibandingkan dengan biota selaras dari perairan eutrofik.

  6. Dynamics of radionuclide exchange in the calcareous algae Halimeda at Enewetak Atoll

    Energy Technology Data Exchange (ETDEWEB)

    Spies, R.B.; Marsh, K.V.; Kercher, J.R.

    1981-01-01

    Measurements of /sup 239+240/Pu in the detrital inclusions and in acid-soluble and acid-insoluble fractions of Halimeda macrophysa showed a 10-fold higher concentration in the acid-insoluble coenocytic filaments than in the acid-soluble fraction. In a depuration experiment with Halimeda incrassata at Enewetak Atoll the loss rate of six radionuclides was measured. Data for /sup 60/Co, /sup 137/Cs, and /sup 102m/Rh were fit to loss curves by using one term for exponential loss; data for /sup 155/Eu, /sup 239+240/Pu, and /sup 241/Am required two terms. For each radionuclide, compartment size and transfer functions were determined for the appropriate one- and two-compartment models. Of 26 possible two-compartment models, only seven gave solutions with our data. Nearly identical loss rates were obtained for /sup 155/Eu, /sup 239+240/Pu, and /sup 241/Am in the fast-exchanging compartments for all seven models. The uptake rates for these nuclides were also similar when uptake rates were normalized to local sediment concentrations. The fast-exchanging compartment probably corresponds to the mucilage surface layer of the coenocytic filaments. The identity of the slow-exchanging compartment is less certain but it may correspond to the skeletal surface.

  7. Dynamics of radionuclide exchange in the calcareous algae Halimeda at Enewetak Atoll

    Energy Technology Data Exchange (ETDEWEB)

    Spies, R.B. (Lawrence Livermore Lab., CA); Marsh, K.V.; Kercher, J.R.

    1981-01-01

    Measurements of /sup 239 +240/Pu in the detrital inclusions and in acid-soluble and acid-insoluble fractions of Halimeda macrophysa showed a 10-fold higher concentration in the acid-insoluble coenocytic filaments than in the acid-soluble fraction. In a depuration experiment with Halimeda incrassata at Enewetak Atoll the loss rate of six radionuclides was measured. Data for /sup 60/Co, /sup 137/Cs, and /sup 102//sup m/Rh were fit to loss curves by using one term for exponential loss; data for /sup 155/Eu, /sup 239 +240/Pu, and /sup 241/Am required two terms. For each radionuclide, compartment size and transfer functions were determined for the apropriate one- and two-compartment models. Of 26 possible two-compartment models, only seven gave solutions with our data. Nearly identical loss rates were obtained for /sup 155/Eu, /sup 239 +240/Pu, and /sup 241/Am in the fast-exchanging compartments for all seven models. The uptake rates for these nuclides were also similar when uptake rates were normalized to local sediment concentrations. The fast-exchanging compartment probably corresponds to the mucilage surface layer of the coenocytic filaments. The identity of the slow-exchanging compartment is less certain but it may correspond to the skeletal surface.

  8. «A posteriori» Determination of the Mixing Proportions of Concrete with Calcareous Aggregates

    Directory of Open Access Journals (Sweden)

    Von Heinz Pisters, -

    1972-09-01

    Full Text Available Not availableCuando en una obra de hormigón han de examinarse a posteriori la proporción de componentes del hormigón endurecido se precisa, frecuentemente, la determinación del contenido de cemento. Los procedimientos seguidos con este fin parten de un tratamiento del hormigón con ácido clorhídrico. En él caso de que el hormigón contenga un árido soluble en él ácido y no se disponga de él por separado, se describe detalladamente un procedimiento de identificación con una corrección sobre el contenido en dióxido de carbono del hormigón. Con arreglo a las determinaciones realizadas de este modo con él hormigón, será también posible en estos casos determinar el contenido de cemento con una precisión de, cuando menos, ± 10%.

  9. Transfer of heavy metals to biota after remediation of contaminated soils with calcareous residues.

    Science.gov (United States)

    Pérez-Sirvent, Carmen; Martínez-Sánchez, Maria Jose; Agudo, Ines; Gonzalez, Eva; Perez-Espinosa, Victor; Belen Martínez, Lucia; Hernández, Carmen; García-Fernandez, Antonio Juan; Bech, Jaime

    2013-04-01

    A study was carried out to evaluate the assimilation of heavy metals by three types of horticultural plants (broccoli, lettuce and leek), different parts of which are destined for human and farm animals consumption (leaves, roots, fruits). Five consecutive crops of each vegetable were obtained in greenhouse. In a second stage, experiments were carried out with rabbits fed with such vegetables. The plants were cultivated in four types of soil. The first one was contaminated by heavy metals (S1), the second was a uncontaminated soil (blank soil) (S2), the third was the material obtained by mixing S1 with residues coming from demolition and construction activities (S3); while the fourth was the result of remediating S1 with lime residues coming from quarries (S4). The total metal content (As, Pb, Cd and Zn) of the soil samples, rizosphere, leached water and vegetable samples, were measured, and both the translocation and bioconcentration factors (TF and BCF, respectively) were calculated. In the second stage, the effect caused in rabbits fed with the vegetables was monitorized using both external observation and the analysis of blood, urine, and the levels of metals in muscles, liver and kidney. The statistical analysis of the results obtained showed that there were no significant differences in the heavy metal levels for the vegetables cultivated in S2, S3 and S4. The results for soil sample S1 did not have a normal distribution since the growing of the vegetables were not homogeneous and also strongly dependent on the type of vegetal. As regards the effect caused in rabbits, significant differences were observed for the animals fed with plants cultivated in S1 compared with the others.

  10. Phosphorus and greenhouse gas dynamics in a drained calcareous wetland soil in Minnesota.

    Science.gov (United States)

    Berryman, Erin M; Venterea, Rodney T; Baker, John M; Bloom, Paul R; Elf, Brandy

    2009-01-01

    Restoration of wetland hydrology can produce ecological benefits but may have unintended consequences. We examined effects of altered water level on release of dissolved reactive phosphorus (DRP) and greenhouse gases (GHG) in soil cores from a marsh being evaluated for restoration. We also measured field concentrations of DRP and other constituents in wetland porewater. Intact cores from a sampling location with higher Fe and lower calcium carbonate (CaCO(3)) contents released more DRP than another location, and displayed higher DRP under completely saturated compared to partly drained conditions. Porewater samples collected from the high-Fe location also contained higher DRP levels. Chemical data suggest that redox-driven reactions largely controlled DRP levels at the high-Fe site, while CaCO(3) adsorption was more important at the low-Fe site. Over the long term, water table elevation may attenuate P draining from the wetland due to decreased mineralization. However, such measures may increase P release in the short term. Raising the water level in soil cores resulted in decreased nitrous oxide (N(2)O) emissions, increased methane (CH(4)) emissions, and an overall increase in total global warming potential (GWP). The proportion of total GWP contributed by N(2)O decreased from 14% to < or = 1% as water level was raised, while the proportion contributed by CH(4) increased from 10 to 20% to 60 to 80%. Restoration of hydrology in the Rice Lake wetland has the potential to affect both local water quality and global air quality. These combined effects complicate the cost-to-benefit analysis of such wetland restoration efforts.

  11. Salinity management using an anionic polymer in a pecan field with calcareous-sodic soil.

    Science.gov (United States)

    Ganjegunte, Girisha K; Sheng, Zhuping; Braun, Robert J

    2011-01-01

    Soil salinity and sodicity have long been recognized as the major concerns for irrigated agriculture in the Trans-Pecos Basin, where fields are being flood irrigated with Rio Grande River water that has elevated salinity. Reclamation of these salt-affected lands is difficult due to fine-texture, high shrink-swell soils with low permeability. Conventional practice of subsoiling to improve soil permeability is expensive and has had limited success on the irrigated soils that have appreciable amounts of readily weatherable Ca minerals. If these native Ca sources can be effectively used to counter sodicity, it can improve soil permeability and reduce amelioration costs. This study evaluated the effects of 3 yr of polyacrylamide (PAM) application at 10 mg L concentration during the first irrigation of the season to evaluate soil permeability, in situ Ca mineral dissolution, and leaching of salts from the effective root zone in a pecan field of El Paso County, TX. Results indicated that PAM application improved water movement throughout the effective root zone that resulted in Na leaching. Polymer application significantly decreased CaCO (estimated based on inorganic C analysis) concentrations in the top 45 cm compared with baseline levels, indicating solubilization and redistribution of calcite. The PAM application also reduced soil electrical conductivity (EC) in the top 60 cm (4.64-2.76 dS m) and sodium adsorption ratio (SAR) from 13.1 to 5.7 mmol L in the top 75-cm depths. As evidence of improved soil conditions, pecan nut yields increased by 34% in PAM-treated fields over the control. Results suggested that PAM application helped in effective use of native Ca sources present in soils of the study site and reduced Na by improving soil permeability. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  12. A Simple and Rapid Method to Evaluate Potentially Mineralizable Nitrogen in Sewage Sludge Amended Calcareous Soils

    Directory of Open Access Journals (Sweden)

    Yazdan Lotfi

    2005-06-01

    Full Text Available Potentially mineralizable nitrogen (PMN can be usually considered as labile nitrogen. Measurement of PMN is expensive and time consuming; therefore, a simpler and more rapid alternative may facilitate routine laboratory analysis. The objective of this study was to determine the relationship between PMN and biological index of nitrogen availability (BINA. The studied soil was previously treated with 0, 25, and 100 tons ha-1 of sewage sludge with 0, 1, 2 and 3 consecutive years of application. Soil samples were taken 6 months after the latest application. PMN was measured according to Stanford and Smith procedure (20 weeks of aerobic incubation with 2 weeks leaching intervals and BINA measured as described by Bundy and Meisinger (7 days of anaerobic incubation at 40˚ C followed by extraction of NH4+. Results showed that PMN was significantly correlated with BINA (r = 0.938, P

  13. Empirical and mechanistic evaluation of NH4(+) release kinetic in calcareous soils.

    Science.gov (United States)

    Ranjbar, F; Jalali, M

    2014-05-01

    Release, fixation, and distribution of ammonium (NH4(+)) as a source of nitrogen can play an important role in soil fertility and plant nutrition. In this study, ten surface soils, after addition of 1,000 mg NH4(+) kg(-1,) were incubated for 1 week at the field capacity moisture and 25 ± 2 °C temperature, and then NH4(+) release kinetic was investigated by sequential extractions with 10 mM CaCl2. Furthermore, NH4(+) distribution among three fractions, including water-soluble, exchangeable, and non-exchangeable, was determined in all soil samples. NH4(+) release was initially rapid followed by a slower reaction, and this was described well with the Elovich equation as an empirical model. The cumulative NH4(+) concentration released in spiked soil samples had a positive significant correlation with sand content and negative ones with pH, exchangeable Ca(2+)m and K(+), cation exchange capacity (CEC), equivalent calcium carbonate (ECC), and clay content. The cation exchange model in the PHREEQC program was successful in mechanistic simulation of the release trend of native and added NH4(+) in all control and spiked soil samples. The results of fractionation experiments showed that the non-exchangeable fraction in control and spiked soil samples was greater than that in water-soluble and exchangeable fractions. Soil properties, such as pH, exchangeable Ca(2+) and K(+), CEC, ECC, and contents of sand and clay, had significant influences on the distribution of NH4(+) among three measured fractions. This study indicated that both native and recently fixed NH4(+), added to soil through the application of fertilizers, were readily available for plant roots during 1 week after exposure.

  14. Geochemistry of calcareous sediments from the SW Carlsberg Ridge: Evidence for deeper carbonate compensation depth

    Digital Repository Service at National Institute of Oceanography (India)

    Valsangkar, A.B.; Ambre, N.V.

    trace metals and are depleted in the other. Variation with respect to depth is significant for CaCO sub(3) (8.5-79.8%) and benthic ratios (1.5-32.5) whereas P sub(2)O sub(5) (0.28-0.38%) and organic carbon (0.18-0.46%) is low and constant. Correlation...

  15. Role of a productive lake in carbon sequestration within a calcareous catchment

    Energy Technology Data Exchange (ETDEWEB)

    Nõges, Peeter, E-mail: peeter.noges@emu.ee [Centre for Limnology, Institute of Agricultural and Environmental Sciences, Estonian University of Life Sciences, 61117 Rannu, Tartu County (Estonia); Cremona, Fabien; Laas, Alo [Centre for Limnology, Institute of Agricultural and Environmental Sciences, Estonian University of Life Sciences, 61117 Rannu, Tartu County (Estonia); Martma, Tõnu [Institute of Geology, Tallinn University of Technology, Ehitajate tee 5, 19086 Tallinn (Estonia); Rõõm, Eva-Ingrid [Centre for Limnology, Institute of Agricultural and Environmental Sciences, Estonian University of Life Sciences, 61117 Rannu, Tartu County (Estonia); Toming, Kaire [Centre for Limnology, Institute of Agricultural and Environmental Sciences, Estonian University of Life Sciences, 61117 Rannu, Tartu County (Estonia); Estonian Marine Institute, University of Tartu, Mäealuse 14, 12618 Tallinn (Estonia); Viik, Malle; Vilbaste, Sirje; Nõges, Tiina [Centre for Limnology, Institute of Agricultural and Environmental Sciences, Estonian University of Life Sciences, 61117 Rannu, Tartu County (Estonia)

    2016-04-15

    For a long time, lakes were considered unimportant in the global carbon (C) cycle because of their small total area compared to the ocean. Over the last two decades, a number of studies have highlighted the important role of lakes in both sequestering atmospheric C and modifying the C flux from the catchment by degassing CO{sub 2} and methane and burying calcite and organic matter in the sediment. Based on a full C mass balance, high frequency measurements of lake metabolism and stable isotope analysis of a large shallow eutrophic lake in Estonia, we assess the role alkaline lakes play in augmenting the strength of terrestrial carbonate weathering as a temporary CO{sub 2} sink. We show that a large part of organic C buried in the sediments in this type of lakes originates from the catchment although a direct uptake from the atmosphere during periods of intensive phytoplankton growth in eutrophic conditions contributes to the carbon sink. - Highlights: • Terrestrial carbonate weathering is considered a temporary sink for CO{sub 2.} • Alkaline lakes precipitate calcite reverting chemical weathering reactions. • Algal uptake increased δ{sup 13}C of dissolved inorganic C while passing through the lake. • 40–70% of sediment organic C originated from catchment alkalinity export. • Biological uptake of released CO{sub 2} counteracts emissions from reversed weathering.

  16. Potential diagenetic and detrital sources for calcareous sediments from the Carlsberg Ridge, Indian Ocean

    Digital Repository Service at National Institute of Oceanography (India)

    Valsangkar, A.B.; Borole, D.V.; Shejwalkar, A.S.; Kalangutkar, N.G.; Fernandes, N.O.; Dias, C.C.

    ., Cruise report of RSS Charles Darwin (CD-149) (18 July–6 August 2003), Southampton Oceanography Centre, UK, p. 3. 11. Anon, Cruise report of ORV Sagar Kanya (SK-207) (13 July–19 August 2004), National Institute of Oceanography, Dona Paula, Goa, p. 27...

  17. Metal contamination disturbs biochemical and microbial properties of calcareous agricultural soils of the Mediterranean area.

    Science.gov (United States)

    de Santiago-Martín, Ana; Cheviron, Natalie; Quintana, Jose R; González, Concepción; Lafuente, Antonio L; Mougin, Christian

    2013-04-01

    Mediterranean climate characteristics and carbonate are key factors governing soil heavy-metal accumulation, and low organic matter (OM) content could limit the ability of microbial populations to cope with resulting stress. We studied the effects of metal contamination on a combination of biological parameters in soils having these characteristics. With this aim, soils were spiked with a mixture of cadmium, copper, lead, and zinc, at the two limit values proposed by current European legislation, and incubated for ≤12 months. Then we measured biochemical (phosphatase, urease, β-galactosidase, arylsulfatase, and dehydrogenase activities) and microbial (fungal and bacterial DNA concentration by quantitative polymerase chain reaction) parameters. All of the enzyme activities were strongly affected by metal contamination and showed the following inhibition sequence: phosphatase (30-64 %) soils was attributed to the different proportion of fine mineral fraction, OM, crystalline iron oxides, and divalent cations in soil solution. The decrease of fungal DNA concentration in metal-spiked soils was negligible, whereas the decrease of bacterial DNA was ~1-54 % at the lowest level and 2-69 % at the highest level of contamination. The lowest bacterial DNA decrease occurred in soils with the highest OM, clay, and carbonate contents. Finally, regarding the strong inhibition of the biological parameters measured and the alteration of the fungal/bacterial DNA ratio, we provide strong evidence that disturbance on the system, even within the limiting values of contamination proposed by the current European Directive, could alter key soil processes. These limiting values should be established according to soil characteristics and/or revised when contamination is produced by a mixture of heavy metals.

  18. Modification of the USLE K factor for soil erodibility assessment on calcareous soils in Iran

    Science.gov (United States)

    Ostovari, Yaser; Ghorbani-Dashtaki, Shoja; Bahrami, Hossein-Ali; Naderi, Mehdi; Dematte, Jose Alexandre M.; Kerry, Ruth

    2016-11-01

    The measurement of soil erodibility (K) in the field is tedious, time-consuming and expensive; therefore, its prediction through pedotransfer functions (PTFs) could be far less costly and time-consuming. The aim of this study was to develop new PTFs to estimate the K factor using multiple linear regression, Mamdani fuzzy inference systems, and artificial neural networks. For this purpose, K was measured in 40 erosion plots with natural rainfall. Various soil properties including the soil particle size distribution, calcium carbonate equivalent, organic matter, permeability, and wet-aggregate stability were measured. The results showed that the mean measured K was 0.014 t h MJ- 1 mm- 1 and 2.08 times less than the estimated mean K (0.030 t h MJ- 1 mm- 1) using the USLE model. Permeability, wet-aggregate stability, very fine sand, and calcium carbonate were selected as independent variables by forward stepwise regression in order to assess the ability of multiple linear regression, Mamdani fuzzy inference systems and artificial neural networks to predict K. The calcium carbonate equivalent, which is not accounted for in the USLE model, had a significant impact on K in multiple linear regression due to its strong influence on the stability of aggregates and soil permeability. Statistical indices in validation and calibration datasets determined that the artificial neural networks method with the highest R2, lowest RMSE, and lowest ME was the best model for estimating the K factor. A strong correlation (R2 = 0.81, n = 40, p soils.

  19. Landscape history, calcareous fen development and historical events in the Slovak Eastern Carpathians

    Czech Academy of Sciences Publication Activity Database

    Jamrichová, Eva; Hájková, Petra; Horsák, M.; Rybníčková, E.; Lacina, A.; Hájek, Michal

    2014-01-01

    Roč. 23, č. 5 (2014), s. 497-513 ISSN 0939-6314 Institutional support: RVO:67985939 Keywords : forest development * spring fen * multi-proxy Subject RIV: EF - Botanics Impact factor: 2.648, year: 2014

  20. Topsoil and fertilizer effects on ground cover growth on calcareous minesoils

    International Nuclear Information System (INIS)

    Kost, D.A.; Vimmerstedt, J.P.

    1997-01-01

    Canopy cover and above ground biomass of herbaceous species was measured in four studies for five years (1989-1993) in southeastern Ohio; on Central Ohio Coal Company's Muskingum Mine, 5 km South of Cumberland. Three studies compared graded cast overburden, standard graded topsoil (30 cm depth), and ripped topsoil. The fourth study lacked the ripped topsoil treatment. In 1987 two studies were seeded with both a standard and a modified mixture of grass and legume species, and two studies used the modified mix only. A nitrogen rate study used 45, 90 or 135 kg/ha of N applied on two occasions, and a phosphorus fertilizer study used rock phosphate amendment at 0, 1120, or 2240 kg/ha and triple superphosphate amendment at 0, 280, or 560 kg/ha. Based on one clipping per year, overall average biomass (Mg/ha dry weight) was slightly greater on standard topsoil (3.34), and ripped topsoil (3.30) than on cast overburden (3.09). Biomass did not differ significantly (p=0.05) on standard topsoil versus cast overburden for 15 of 19 comparisons. Legume biomass (Mg/ha, measured for 3 or 4 years) averaged 0.84 on standard topsoil, 0.75 on ripped topsoil, and 1.16 on cast overburden. In three studies, legume biomass was 50% higher on cast overburden than the topsoils, but differences among the soil surfaces were decreasing by 50% higher on cast overburden than the topsoils, but differences among the soil surfaces were decreasing by 1993. Nitrogen fertilizer increased ground cover only in the year when fertilizer was applied. Phosphorus fertilizer treatments had no significant effects. Ground cover showed no signs of deterioration during the last measurements in 1993. Observations in 1995 indicated dense canopy cover on all soil surfaces with substantial invasion by goldenrods (Solidago spp.) only on topsoils. 16 refs., 4 tabs

  1. Bio-chemical properties of sandy calcareous soil treated with rice straw-based hydrogels

    Directory of Open Access Journals (Sweden)

    Houssni El-Saied

    2016-06-01

    The results obtained show that, application of the investigated hydrogels positively affects bio-chemical properties of the soil. These effects are assembled in the following: (a slightly decreasing soil pH, (b increasing cation exchange capacity (CEC of the soil indicating improvement in activating chemical reactions in the soil, (c increasing organic matter (OM, organic carbon, total nitrogen percent in the soil. Because the increase in organic nitrogen surpassed that in organic carbon, a narrower CN ratio of treated soils was obtained. This indicated the mineralization of nitrogen compounds and hence the possibility to save and provide available forms of N to growing plants, (d increasing available N, P and K in treated soil, and (e improving biological activity of the soil expressed as total count of bacteria and counts of Azotobacter sp., phosphate dissolving bacteria (PDB, fungi and actinomycetes/g soil as well as the activity of both dehydrogenase and phosphatase.

  2. Effects of wastewater irrigation on soil sodicity and nutrient leaching in calcareous soils

    NARCIS (Netherlands)

    Jalali, M.; Merikhpour, H.; Kaledhonkar, M.J.; Zee, van der S.E.A.T.M.

    2008-01-01

    Soil column studies were conducted with two soils to assess the effects of irrigation with wastewater on soil and groundwater quality. Upon the application of wastewater, exchange occurred between solution sodium (Na+) and exchangeable cations (Ca2+, Mg2+, K+), whereby these cations were released

  3. Role of a productive lake in carbon sequestration within a calcareous catchment.

    Science.gov (United States)

    Nõges, Peeter; Cremona, Fabien; Laas, Alo; Martma, Tõnu; Rõõm, Eva-Ingrid; Toming, Kaire; Viik, Malle; Vilbaste, Sirje; Nõges, Tiina

    2016-04-15

    For a long time, lakes were considered unimportant in the global carbon (C) cycle because of their small total area compared to the ocean. Over the last two decades, a number of studies have highlighted the important role of lakes in both sequestering atmospheric C and modifying the C flux from the catchment by degassing CO2 and methane and burying calcite and organic matter in the sediment. Based on a full C mass balance, high frequency measurements of lake metabolism and stable isotope analysis of a large shallow eutrophic lake in Estonia, we assess the role alkaline lakes play in augmenting the strength of terrestrial carbonate weathering as a temporary CO2 sink. We show that a large part of organic C buried in the sediments in this type of lakes originates from the catchment although a direct uptake from the atmosphere during periods of intensive phytoplankton growth in eutrophic conditions contributes to the carbon sink. Copyright © 2016 Elsevier B.V. All rights reserved.

  4. Alternative potassium source for the cultivation of ornamental sunflower

    Directory of Open Access Journals (Sweden)

    Sabrina Thereza dos Santos Torqueti

    2016-06-01

    Full Text Available ABSTRACT Brazil is dependent on importation of fertilizers, especially the potassics. Rocks and minerals that contain nutrients have a potential for use in agriculture as fertilizer, especially those of slow solubilization and that exhibit residual effect. In this context, the objective was to assess the feasibility of glauconite rock as potassium source for the cultivation of ornamental sunflower. The experiment was conducted under controlled conditions arranged in an entirely randomized design, in a 4x4 + 4 factorial scheme, with four replicates and one plant per plot. Four glauconite-based fertilizers were used as a potassium source: fine grained glauconite, fine grained organo-mineral glauconite, coarse grained glauconite and coarse grained organo-mineral glauconite, in four doses, as well as an additional treatment with four doses of KCl, the principal conventional source of the nutrient. The height of the flower stalks, the diameter of the stem and floral capitulum, the number of cultivation days and post-harvest durability were evaluated. The application of KCl yielded the production of flower stems with greater height and larger capitulum diameter in relation to the supply of glauconite. Among the glauconite based fertilizers, the fine grained organo-mineral product provided the best flower charateristics. The postharvest commercial durability of the flower stalks was higher in plants that received the glauconite and fine grained organo-mineral glauconite. The fine grained organo-mineral glauconite surpasses all other alternative sources of potassium in relation to the agronomic characteristics evaluated.

  5. Latest Paleocene lithologic and biotic events in neritic deposits of southwestern New Jersey

    Science.gov (United States)

    Gibson, Thomas G.; Bybell, Laurel M.; Owens, James P.

    1993-01-01

    In the southwestern New Jersey Coastal Plain, four drill holes contain continuous neritic sedimentation across the Paleocene/Eocene boundary (calcareous nannofossil Zone NP 9/NP 10 boundary). Significant lithologic and biotic changes occur in these strata near the top of the Paleocene. Global warming, increased precipitation, and other oceanographic and climatic events that have been recognized in high-latitude, deep-oceanic deposits of the latest Paleocene also influenced mid-latitude, shallow-marine, and terrestrial environments of the western North Atlantic. The diverse, well-preserved calcareous nannofossil flora that is present throughout the entire New Jersey boundary section accurately places these events within the uppermost part of the upper Paleocene Zone NP 9. Several rapid but gradational changes occur within a 1.1-m interval near the top of Zone NP 9. The changes include (1) a change in lithology from glauconitic quartz sand to clay, (2) a change in clay mineral suites from illite/smectite-dominated to kaolinite-dominated, (3) a change in benthic foraminiferal assemblages to a lower diversity fauna suggestive of low-oxygen environments, (4) a significant increase in planktonic foraminiferal abundance, and (5) an increased species turnover rate in marine calcareous nannofossils. Pollen was sparse in the New Jersey drill holes, but terrestrial sporomorph species in Virginia exhibit increased turnover rates at a correlative level. Foraminiferal assemblages and lithology indicate that relative sea level rose in New Jersey at the same time as these late Paleocene events occurred in late Biochron NP 9. The higher sea levels influenced sediment type and absolute abundance of planktonic foraminifers in the deposits. Above the initial increase of kaolinite in the upper part of Zone NP 9, the kaolinite percentage continues to increase, and the maximum kaolinite value occurs in the uppermost part of Zone NP 9. There are few changes in either the sediments or the

  6. Integrated Paleoenvironmental Reconstruction and Taphonomy of a Unique Upper Cretaceous Vertebrate-Bearing Locality (Velaux, Southeastern France.

    Directory of Open Access Journals (Sweden)

    Aude Cincotta

    Full Text Available The Velaux-La Bastide Neuve fossil-bearing site (Bouches-du-Rhône, France has yielded a diverse vertebrate assemblage dominated by dinosaurs, including the titanosaur Atsinganosaurus velauciensis. We here provide a complete inventory of vertebrate fossils collected during two large-scale field campaigns. Numerous crocodilian teeth occur together with complete skulls. Pterosaur, hybodont shark and fish elements are also represented but uncommon. Magnetostratigraphic analyses associated with biostratigraphic data from dinosaur eggshell and charophytes suggest a Late Campanian age for the locality. Lithologic and taphonomic studies, associated with microfacies and palynofacies analyses, indicate a fluvial setting of moderate energy with broad floodplain. Palynomorphs are quite rare; only three taxa of pollen grains occur: a bisaccate taxon, a second form probably belonging to the Normapolles complex, and another tricolporate taxon. Despite the good state of preservation, these taxa are generally difficult to identify, since they are scarce and have a very minute size. Most of the vertebrate remains are well preserved and suggest transport of the carcasses over short distances before accumulation in channel and overbank facies, together with reworked Aptian grains of glauconite, followed by a rapid burial. The bones accumulated in three thin layers that differ by their depositional modes and their taphonomic histories. Numerous calcareous and iron oxides-rich paleosols developed on the floodplain, suggesting an alternating dry and humid climate in the region during the Late Campanian.

  7. Source areas of the Grybów sub-basin: micropaleontological, mineralogical and geochemical provenance analysis (Outer Western Carpathians, Poland

    Directory of Open Access Journals (Sweden)

    Oszczypko-Clowes Marta

    2015-12-01

    Full Text Available The Grybów Unit occurring in the Ropa tectonic window was the subject of micropaleontological and geochemical investigation. Studies, based on calcareous nannofossils, proved that the level of reworked microfossil is not higher than 22 % and it varies between two sections. Quantitative analyses of the reworked assemblages confirmed the domination of Cretaceous and Middle Eocene species. The Sub-Grybów Beds, Grybów Marl Formation and Krosno Beds were assigned to the Late Oligocene and represent the terminal flysch facies. Detrital material accumulated in the Oligocene sediments originated from the Marmarosh Massif, which is the eastern prolongation of the Fore-Magura Ridge. The microscopically obtained petrological features agree with the chemical composition of the samples. Mica flakes, rounded grains of glauconite, heavy mineral assemblage, including abraded grains of zircon, rutile and tourmaline as well as charred pieces of plant tissues are reworked components. Enrichment in zircon and rutile is confirmed geochemically by positive correlation between Zr and SiO2. Zr addition is illustrated on 10×Al2O3–Zr–200×TiO2 and Zr/Sc vs. Th/Sc diagrams. Interpretation of the A–CN–K diagram and variety of CIA and CPA values indicate that the source rocks were intensely weathered granite-type rocks.

  8. Biostratigraphy and carbon isotope stratigraphy of uppermost Cretaceous-lower Cenozoic Muzzle Group in middle Clarence valley, New Zealand

    International Nuclear Information System (INIS)

    Hollis, C.J.; Field, B.D.; Jones, C.M.; Strong, C.P.; Wilson, G.J.; Dickens, G.R.

    2005-01-01

    Muzzle Group strata exposed along southeast-flowing tributaries of the Clarence River valley, Marlborough, record hemipelagic-pelagic sedimentation across a high latitude (c. 55 degrees S), terrigenous sediment-starved, continental margin from latest Cretaceous to middle Eocene times. Studies of dinoflagellates, foraminifera, calcareous nannofossils, and radiolarians have been integrated with bulk carbonate δ 13 C profiles to establish the chronostratigraphy for two stratigraphic sections along Bluff and Muzzle Streams, middle Clarence valley. The two sections comprise similar successions. Uppermost Cretaceous (upper Haumurian) micritic limestone of Mead Hill Formation is overlain unconformably by Teredo Limestone, a c. 0.25 m thick bed of highly glauconitic, calcareous sandstone. This unit, the basal member of Amuri Limestone, is overlain conformably by c. 15 m thick Lower Limestone, micritic limestone that is glauconitic at base and progressively more marl-rich in its upper part. Lower Limestone grades up into Lower Marl, a poorly exposed, 40-70 m thick unit of alternating marl and micritic limestone beds. Biostratigraphy indicates that the base of Amuri Limestone is younger at Bluff Stream (earliest Eocene, early Waipawan) than at Muzzle Stream (late Paleocene, late Teurian). In the condensed (12 m) upper Paleocene-lower Eocene Amuri Limestone sequence at Muzzle Stream, a trend in δ 13 C from high (≥2.4 permille) to low (≤1 permille) values is consistent with global records across three major climate or carbon cycle perturbations: the late Paleocene carbon isotope maximum (PCIM, 59-56 Ma), the initial Eocene thermal maximum (IETM, 55.5 Ma), and the early Eocene climatic optimum (EECO, 53-50 Ma). Probably only the upper PCIM is preserved in the 4 m thick siliceous limestone interval overlying Teredo Limestone. The IETM is well-defined by a 1 permille negative δ 13 C excursion at the base of a 0.8 m thick marl-rich unit (Dee Marl), 5 m above the base of

  9. Wheat phytotoxicity from arsenic and cadmium separately and together in solution culture and in a calcareous soil

    Energy Technology Data Exchange (ETDEWEB)

    Cao Qing [Research Center for Eco-environmental Sciences, Chinese Academy of Sciences, Beijing 100085 (China); Hu Qinhong [Lawrence Livermore National Laboratory, University of California, Livermore, CA 94550 (United States); Khan, Sardan [Research Center for Eco-environmental Sciences, Chinese Academy of Sciences, Beijing 100085 (China); Department of Environmental Sciences, University of Peshawar, 25120 Peshawar (Pakistan); Wang Zijian [Research Center for Eco-environmental Sciences, Chinese Academy of Sciences, Beijing 100085 (China); Lin Aijun [College of Chemical Engineering, Beijing University of Chemical Technology, Beijing 100029 (China); Du Xin [Research Center for Eco-environmental Sciences, Chinese Academy of Sciences, Beijing 100085 (China); Zhu Yongguan [Research Center for Eco-environmental Sciences, Chinese Academy of Sciences, Beijing 100085 (China)], E-mail: ygzhu@rcees.ac.cn

    2007-09-05

    The toxicity of two toxic elements, arsenic (As) and cadmium (Cd) (individually or in combination) on root elongation of wheat seedlings (Triticum aestivum, L.) were investigated both in hydroponics and in soils freshly spiked with the toxic elements. Median effective concentration (EC{sub 50}) and non-observed effect concentration (NOEC) were used to investigate the toxic thresholds and potencies of the two elements. The EC{sub 50} for As was 0.97 {mu}M in hydroponics and 196 mg kg{sup -1} in soil, and 4.32 {mu}M and 449 mg kg{sup -1} for Cd, respectively. Toxic unit (TU) and additive index (AI) concepts were introduced to determine the combined outcomes, and different behaviors were obtained: synergism in solution culture (EC{sub 50mix} = 0.36TU{sub mix} and AI: 1.76) and antagonism in soil experiments (EC{sub 50mix} = 1.49TU{sub mix} and AI: -0.33). Furthermore, the data of soil bioavailable As and Cd cannot explain the discrepancy between the results derived from soil and hydroponics experiments.

  10. Wheat phytotoxicity from arsenic and cadmium separately and together in solution culture and in a calcareous soil

    International Nuclear Information System (INIS)

    Cao Qing; Hu Qinhong; Khan, Sardan; Wang Zijian; Lin Aijun; Du Xin; Zhu Yongguan

    2007-01-01

    The toxicity of two toxic elements, arsenic (As) and cadmium (Cd) (individually or in combination) on root elongation of wheat seedlings (Triticum aestivum, L.) were investigated both in hydroponics and in soils freshly spiked with the toxic elements. Median effective concentration (EC 50 ) and non-observed effect concentration (NOEC) were used to investigate the toxic thresholds and potencies of the two elements. The EC 50 for As was 0.97 μM in hydroponics and 196 mg kg -1 in soil, and 4.32 μM and 449 mg kg -1 for Cd, respectively. Toxic unit (TU) and additive index (AI) concepts were introduced to determine the combined outcomes, and different behaviors were obtained: synergism in solution culture (EC 50mix = 0.36TU mix and AI: 1.76) and antagonism in soil experiments (EC 50mix = 1.49TU mix and AI: -0.33). Furthermore, the data of soil bioavailable As and Cd cannot explain the discrepancy between the results derived from soil and hydroponics experiments

  11. Wheat phytotoxicity from arsenic and cadmium separately and together in solution culture and in a calcareous soil

    Energy Technology Data Exchange (ETDEWEB)

    Cao, Q; Hu, Q; Khan, S; Wang, Z; Lin, A; Du, X; Zhu, Y

    2007-03-05

    The toxicity effect of two deleterious elements of arsenic (As) and cadmium (Cd) (individually or in combination) on root elongation of wheat seedlings (Triticum aestivum, L.) were investigated both in hydroponics and in soils freshly spiked with the toxic elements. Median effective concentration (EC{sub 50}) and non-observed effect concentration (NOEC) were used to investigate the toxic thresholds and potencies of the two elements. The EC{sub 50} for As was 0.97 {mu}M in hydroponics and 196 mg {center_dot} kg{sup -1} in soil, and 4.32 {mu}M and 449 mg {center_dot} kg{sup -1} for Cd, respectively. Toxic unit (TU) and additive index (AI) concepts were introduced to determine the combined outcomes, and different behaviors were obtained: synergism in solution culture (EC{sub 50mix} = 0.36 TU{sub mix} and AI: 1.76) and antagonism in soil experiments (EC{sub 50mix} = 1.49 TU{sub mix} and AI: -0.33). Furthermore, the data of soil bioavailable As and Cd can not explain the discrepancy between the results derived from soil and hydroponics experiments.

  12. Heavy metal phytoextraction-natural and EDTA-assisted remediation of contaminated calcareous soils by sorghum and oat.

    Science.gov (United States)

    Mahmood-Ul-Hassan, Muhammad; Suthar, Vishandas; Ahmad, Rizwan; Yousra, Munazza

    2017-10-30

    The abilities of sorghum (Sorghum bicolor L.) and oat (Avena sativa L.) to take up heavy metals from soils amended with ethylenediaminetetraacetic acid (EDTA) were assessed under greenhouse conditions. Both plants were grown in two soils contaminated with heavy metals (Gujranwala-silty loam and Pacca-clay loam). The soils were treated with 0, 0.625, 1.25, and 2.5 mM EDTA kg -1 soil applied at both 45 and 60 days after sowing (DAS); the experiment was terminated at 75 DAS. Addition of EDTA significantly increased concentrations of Cd, Cr, and Pb in roots and shoots, and bio-concentration factors and phytoextraction rates were also increased. Post-harvest soil analysis showed that soluble fractions of metals were also increased significantly. The increase in Cd was ≈ 3-fold and Pb was ≈ 15-fold at the highest addition of EDTA in Gujranwala soil; in the Pacca soil, the increase was less. Similarly, other phytoremediation factors, such as metal translocation, bio-concentration factor, and phytoextraction, efficiency were also maximum when soils were treated with 2.5 mM EDTA kg -1 soil. The study demonstrated that sorghum was better than oat for phytoremediation.

  13. Fast reconnaissance of carbonate dissolution based on the size distribution of calcareous ooze on Walvis Ridge, SE Atlantic Ocean.

    NARCIS (Netherlands)

    Stuut, J.-B. W.; Prins, M.A.; Jansen, J.H.F.

    2002-01-01

    We present a new index of carbonate fragmentation based on the size distribution of bulk sediments in core MD962094 from Walvis Ridge (SE Atlantic Ocean). The carbonate fragmentation index is constructed by taking a ratio of the two coarsest fractions in the grain size distributions of the bulk

  14. The Optimization of Calcareous Fly Ash-Added Cement Containing Grinding Aids and Strength-Improving Additives

    Directory of Open Access Journals (Sweden)

    Gökhan Kaplan

    2018-01-01

    Full Text Available This is an experimental study which explores the physical, mechanical, and economic factors involved in the production of type CEM II A-B/W cement. In this context, 4 cement additives were used in two different dosages (200 and 800 g/t. Class C fly ash was used for composite cement production at ratios of 5%, 20%, and 35%. It was shown that Blaine fineness increases with the increasing fly ash content. The use of fly ash at ratios of 5% and 20% was not found to have any unfavorable effects on the compressive strength at the early days. It is found that the use of additive for improving the early-age strength is preferable when fly ash is used. It is possible to produce Class 52.5 N cement using additives to improve early strength and 20% fly ash. Loss in strength was observed in cement mortars produced using glycol-based grinding aid. Increasing the dosage of chemical additive also led to loss in strength due to nonhomogeneous distribution of hydration products. As a result, grinding fly ash with clinker and the use of cement chemicals contribute to the cement sector in terms of sustainability. It is possible to produce cements with improved mechanical properties especially with the use of 20% fly ash.

  15. Influence of organic amendments on diuron leaching through an acidic and a calcareous vineyard soil using undisturbed lysimeters

    International Nuclear Information System (INIS)

    Thevenot, M.; Dousset, S.; Rousseaux, S.; Andreux, F.

    2008-01-01

    The influence of different organic amendments on diuron leaching was studied through undisturbed vineyard soil columns. Two composts (A and D), the second at two stages of maturity, and two soils (VR and Bj) were sampled. After 1 year, the amount of residues (diuron + metabolites) in the leachates of the VR soil (0.19-0.71%) was lower than in the Bj soil (4.27-8.23%), which could be explained by stronger diuron adsorption on VR. An increase in the amount of diuron leached through the amended soil columns, compared to the blank, was observed for the Bj soil only. This result may be explained by the formation of mobile complexes between diuron and water-extractable organic matter (WEOM) through the Bj soil, or by competition between diuron and WEOM for the adsorption sites in the soil. For both soils, the nature of the composts and their degree of maturity did not significantly influence diuron leaching. - The application of organic amendments increased diuron leaching through a sandy-loam soil, in contrast to a clay-loam soil

  16. Influence of organic amendments on diuron leaching through an acidic and a calcareous vineyard soil using undisturbed lysimeters

    Energy Technology Data Exchange (ETDEWEB)

    Thevenot, M. [UMR 1229 Microbiologie et Geochimie des Sols, CMSE, INRA - Universite de Bourgogne, UFR des Sciences de la Terre et de l' Environnement, 6 Boulevard Gabriel, 21000 Dijon (France)], E-mail: mathieu.thevenot@u-bourgogne.fr; Dousset, S. [UMR 5561 Biogeosciences, CNRS - Universite de Bourgogne, UFR des Sciences de la Terre et de l' Environnement, 6 Boulevard Gabriel, 21000 Dijon (France); Rousseaux, S. [EA 4149 Laboratoire de Recherche en Vigne et Vin, Institut Universitaire de la Vigne et du Vin, rue Claude Ladrey, 21000 Dijon (France); Andreux, F. [UMR 1229 Microbiologie et Geochimie des Sols, CMSE, INRA - Universite de Bourgogne, UFR des Sciences de la Terre et de l' Environnement, 6 Boulevard Gabriel, 21000 Dijon (France)

    2008-05-15

    The influence of different organic amendments on diuron leaching was studied through undisturbed vineyard soil columns. Two composts (A and D), the second at two stages of maturity, and two soils (VR and Bj) were sampled. After 1 year, the amount of residues (diuron + metabolites) in the leachates of the VR soil (0.19-0.71%) was lower than in the Bj soil (4.27-8.23%), which could be explained by stronger diuron adsorption on VR. An increase in the amount of diuron leached through the amended soil columns, compared to the blank, was observed for the Bj soil only. This result may be explained by the formation of mobile complexes between diuron and water-extractable organic matter (WEOM) through the Bj soil, or by competition between diuron and WEOM for the adsorption sites in the soil. For both soils, the nature of the composts and their degree of maturity did not significantly influence diuron leaching. - The application of organic amendments increased diuron leaching through a sandy-loam soil, in contrast to a clay-loam soil.

  17. Comparative uptake of trace elements in vines and olive trees over calcareous soils in western La Mancha

    Science.gov (United States)

    Ángel Amorós, José; Higueras, Pablo; Pérez-de-los-Reyes, Caridad; Jesús García, Francisco; Villaseñor, Begoña; Bravo, Sandra; Losilla, María Luisa; María Moreno, Marta

    2014-05-01

    Grapevine (Vitis vinifera L.) and olive-tree (Olea europea L.) are very important cultures in Castilla-La Mancha for its extension and contribution to the regional economy. This study was carried out in the municipality of Carrión de Calatrava (Ciudad Real) where the variability of soils of different geological origin, with different evolutions giving a great diversity of soils. The metabolism of trace elements in plants has been extensively studied although each soil-plant system must be investigated, especially since small variations in composition can lead to marked differences. It can be stated that the composition of the plant reflects the environment where it is cultivated and the products of the plant (leaves, fruits, juices, etc…) will be influenced by the composition of the soil. The main aim of the work was to compare the uptake of 24 trace elements in grapevine and olive-tree cultivated in the same soil. Samples from surface soils and plant material (leaf) have been analyzed by X-ray fluorescence, obtaining trace elements in mg/kg. It can be concluded that the leaves of grapevines in the studied plots have shown content in elements: -Similar to the olive-tree in case of: Co, Ga, Y, Ta, Th, U y Nd. -Over to the olive-tree in: Sc, V, Cr, Ni, Rb, Sr, Zr, Nb, Ba, La, Ce, Hf y W. -Below to the olive-tree in: Cu, Zn, Cs y Pb. Keywords: woody culture soils, mineral nutrition, X-ray fluorescence.

  18. Sr{sup 90} determination in calcareous water; Determination du {sup 90}Sr dans des eaux chargees en calcium

    Energy Technology Data Exchange (ETDEWEB)

    Cohen, P; Pardo, G; Wormser, G [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1958-07-01

    The Straub method (ref. 2) for determination of radioactive strontium in water containing calcium is valid within very wide limits, and particularly in the case of residual water from the chemical purification treatment of the radioactive liquid effluent at the C.E.N. Saclay. (author) [French] La methode de Straub (ref. 2) de determination du strontium radioactif dans une eau chargee en calcium est valable dans des limites tres larges et en particulier dans le cas d'eaux residuaires provenant du traitement d'epuration chimique des effluents liquides radioactifs du C.E.N. de Saclay. (auteur)

  19. Behavior and environmental impacts of radionuclides during the hydrometallurgy of calcareous and argillaceous rocks, southwestern Sinai, Egypt

    Energy Technology Data Exchange (ETDEWEB)

    El Aassy, Ibrahim E. [Nuclear Materials Authority (Egypt); Nada, Afaf A., E-mail: afafhero_nada@yahoo.com [Faculty of Women for Arts, Science and Education (Egypt); El Galy, Mohamed M.; El Feky, Mohamed G. [Nuclear Materials Authority (Egypt); Abd El Maksoud, Thanaa M.; Talaat, Shadia M. [Faculty of Women for Arts, Science and Education (Egypt); Ibrahim, Eman M. [Nuclear Materials Authority (Egypt)

    2012-06-15

    The hydrometallurgy of radionuclides means getting the radioelements from the rocks into solution by leaching, getting the radionuclides from the solution by extraction process, and then precipitation of the desired elements to obtain concentrate. The follow-up of the radionuclides during these processes is the main target of this work to identify the identity of the original samples, pregnant solutions (leachates), residuals and the concentrate. Six samples were chosen to achieve this work. The leaching process was carried out under the conditions; 20-30% acid (H{sub 2}SO{sub 4}) concentration, 1:3 solid/liquid ratios, 60 min stirring time at room temperature. The activity concentrations of {sup 238}U, {sup 235}U, {sup 234}U, {sup 226}Ra, {sup 214}Pb, {sup 214}Bi, {sup 232}Th and {sup 40}K were measured in the original samples, residuals and U-concentrate (Bq/kg), and leachates (Bq/ Script-Small-L). The results indicate that, the radionuclides before {sup 226}Ra in the {sup 238}U decay series are more leachable (released) than those from {sup 226}Ra to {sup 214}Bi in the order; {sup 234}U>{sup 238}U={sup 235}U Much-Greater-Than {sup 226}Ra>{sup 214}Pb>{sup 214}Bi. {sup 232}Th and {sup 40}K are immobile under the present conditions. The radiological hazards of natural radioactivity in the original samples, leachates, residuals and U-concentrate were calculated and compared with the internationally recommended values and were found to be much higher than the world average values. - Highlights: Black-Right-Pointing-Pointer Original rocks, leachates, residuals and concentrate were studied. Black-Right-Pointing-Pointer Radionuclides concentrations were examined through different phases. Black-Right-Pointing-Pointer Radionuclides are more leachable before than that after {sup 226}Ra series. Black-Right-Pointing-Pointer Radiological hazards were compared with the international values. Black-Right-Pointing-Pointer Cautions should be taken in considerations during mining process.

  20. Characterization of non-calcareous 'thin' red clay from south-eastern Brazil: applicability in wall tile manufacture

    Energy Technology Data Exchange (ETDEWEB)

    Sousa, S. J.G.; Holanda, J. N.F., [Grupo de Materiais Ceramicos - LAMAV-CCT, Universidade Estadual do Norte Fluminense Darcy Ribeiro, Campos dos Goytacazes, RJ (Brazil)

    2012-04-15

    In this work the use of 'thin' red clay from south-eastern Brazil (Campos dos Goytacazes, RJ) as raw material for the manufacture of wall tile was investigated. A wide range of characterization techniques was employed, including X-ray diffraction (XRD), X-ray fluorescence (XRF), scanning electron microscopy (SEM), grain-size analysis, and thermogravimetric analysis. The wall tile body was prepared by the dry process. The tile pieces were uniaxially pressed and fired between 1080 - 1180 deg C using a fast-firing cycle. The following technological properties were determined: linear shrinkage, water absorption, apparent density, and flexural strength. The development of the microstructure was followed by SEM and XRD analyses. It was found that the 'thin' red clay is kaolinitic type containing a substantial amount of quartz. The results also showed that the 'thin' red clay could be used in the manufacture of wall tiles, as they present properties compatible with those specified for class BIII of ISO 13006 standard. (author)

  1. Groundwater resources evaluation in calcareous limestone using geoelectrical and VLF-EM surveys (El Salloum Basin, Egypt)

    Science.gov (United States)

    Zarif, Fardous; Slater, Lee; Mabrouk, Mohamed; Youssef, Ahmed; Al-Temamy, Ayman; Mousa, Salah; Farag, Karam; Robinson, Judy

    2018-01-01

    Understanding and developing groundwater resources in arid regions such as El Salloum basin, along the northwestern coast of Egypt, remains a challenging issue. One-dimensional (1D) electrical sounding (ES), two-dimensional (2D) electrical resistivity imaging (ERI), and very low frequency electromagnetic (VLF-EM) measurements were used to investigate the hydrogeological framework of El Salloum basin with the aim of determining the potential for extraction of potable water. 1D resistivity sounding models were used to delineate geoelectric sections and water-bearing layers. 2D ERI highlighted decreases in resistivity with depth, attributed to clay-rich limestone combined with seawater intrusion towards the coast. A depth of investigation (DOI) index was used to constrain the information content of the images at depths up to 100 m. The VLF-EM survey identified likely faults/fractured zones across the study area. A combined analysis of the datasets of the 1D ES, 2D ERI, and VLF-EM methods identified potential zones of groundwater, the extent of seawater intrusion, and major hydrogeological structures (fracture zones) in El Salloum basin. The equivalent geologic layers suggest that the main aquifer in the basin is the fractured chalky limestone middle Miocene) south of the coastal plain of the study area. Sites likely to provide significant volumes of potable water were identified based on relatively high resistivity and thickness of laterally extensive layers. The most promising locations for drilling productive wells are in the south and southeastern parts of the region, where the potential for potable groundwater increases substantially.

  2. Nitrous oxide emission and denitrifier communities in drip-irrigated calcareous soil as affected by chemical and organic fertilizers.

    Science.gov (United States)

    Tao, Rui; Wakelin, Steven A; Liang, Yongchao; Hu, Baowei; Chu, Guixin

    2018-01-15

    The effects of consecutive application of chemical fertilizer with or without organic fertilizer on soil N 2 O emissions and denitrifying community structure in a drip-irrigated field were determined. The four fertilizer treatments were (i) unfertilized, (ii) chemical fertilizer, (iii) 60% chemical fertilizer plus cattle manure, and (iv) 60% chemical fertilizer plus biofertilizer. The treatments with organic amendments (i.e. cattle manure and biofertilizer) reduced cumulative N 2 O emissions by 4.9-9.9%, reduced the N 2 O emission factor by 1.3-42%, and increased denitrifying enzyme activities by 14.3-56.2%. The nirK gene copy numbers were greatest in soil which received only chemical fertilizer. In contrast, nirS- and nosZ-copy numbers were greatest in soil amended with chemical fertilizer plus biofertilizer. Chemical fertilizer application with or without organic fertilizer significantly changed the community structure of nirK-type denitrifiers relative to the unfertilized soil. In comparison, the nirS- and nosZ-type denitrifier genotypes varied in treatments receiving organic fertilizer but not chemical fertilizer alone. The changes in the denitrifier communities were closely associated with soil organic carbon (SOC), NO 3 - , NH 4 + , water holding capacity, and soil pH. Modeling indicated that N 2 O emissions in this soil were primarily associated with the abundance of nirS type denitrifying bacteria, SOC, and NO 3 - . Overall, our findings indicate that (i) the organic fertilizers increased denitrifying enzyme activity, increased denitrifying-bacteria gene copy numbers, but reduced N 2 O emissions, and (ii) nirS- and nosZ-type denitrifiers were more sensitive than nirK-type denitrifiers to the organic fertilizers. Copyright © 2017. Published by Elsevier B.V.

  3. Observations on Dissocladella annulata (Elliott, 1993 nov. comb. (Calcareous algae, Dasycladales from the Cenomanian of west Serbia

    Directory of Open Access Journals (Sweden)

    Radoičić Rajka

    2010-01-01

    Full Text Available Based on material from the type area at Tetrebovo in the Zlatibor massif of WSerbia, the Cenomanian dasycladalean alga originally described as Harlanjohnsonella annulata by ELLIOTT (1968, typified 1993 in: GRANIER & DELOFFRE, is emended and revisited as Dissocladella annulata (ELLIOTT nov. comb. The evidence of tufts of short secondaries arising at the top of the drop-like primaries allows its transfer to the genus Dissocladella PIA, 1936. This species displays a different degree of skeleton calcification which is described in detail. The monospecific genus Harlanjohnsonella ELLIOTT becomes invalid, as being a junior synonym of Dissocladella.

  4. Methods of pH determination in Calcareous soils of Oman: The effect of Electrolyte and soil solution ratio

    International Nuclear Information System (INIS)

    Al-Busaidi, A.; Cookson, P.

    2002-01-01

    Determination of pH assists in understanding many reactions that occur in soil. Soil pH values are highly sensitive to the procedure used for determination. In this study, pH was measured in different electrolytes [distilled water (pHw), 0.01MCaCl2 (pHCa), 1MKCl (pHk), and 0.01MBaCl2 (pHba)] with different soil: electrolyte ratios (i.e. 1:1, 1:2.5 and 1:5). The objective was to determine the effect of each electrolyte and dilution ratio on pH of saline and non-saline soils from Oman. It was found that ph values varied significantly between electrolytes and with different dilution ratios. Linear regression equations were generated between electrolytes, dilution ratios and were mostly significant. Soil pH values determined in different electrolytes were significantly interrelated. Water appeared as a highly suitable solvent for soil pH measurements because it is simple and values familiar to soil users. However, alkaline errors and electrode instabilities due to liquid junction and soluble salt effects, affected soil pH measurements, especially in water, and resulted in alkaline errors during pH measurements. Errors were minimized when pH was measured in electrolytes rather than in water. (author)

  5. The influence of coniferous canopies on understorey vegetation and soils in mountain forests of the northern Calcareous Alps

    International Nuclear Information System (INIS)

    Ewald, Joerg

    2000-01-01

    Compositional and edaphic gradients were studied in montane forests of the Bavarian Alps (Germany), in which natural mixed deciduous-coniferous tree layers have been altered by past management in favour of Picea abies. Data on species composition and ecological factors were collected in a stratified random sample of 84 quadrats comprising a gradient from pure Picea to pure Fagus sylvatica stands. Data about the understorey composition were subjected to indirect (DCA) and direct gradient analysis (RDA) with the proportion of Picea in the canopy as a constraining variable. Three principal components of a matrix containing seven descriptors of mineral soil, relief and tree layer cover were included as covariables describing the variability of primary ecological factors. Gradients of organic topsoil morphology and chemistry were extracted correspondingly. Responses of individual species, species group and topsoil attributes were studied by simple and partial correlation analysis. Mosses were significantly more abundant and diverse under Picea stands. Few graminoid and herb species were partially associated with Picea, and total understorey richness and cover did not differ systematically by stand type. No relationship between tree layer and understorey diversity was detected at the studied scale. Juvenile Fagus sylvatica was the only woody species significantly less abundant under Picea. In the topsoil lower base saturation, lower pH and larger C/N ratios in the litter layer were partially attributable to the proportion of Picea, only for base saturation a relationship was detected in greater soil depth also. The frequency of broad humus form types did not differ by tree species, nor was overall depth of organic forest floor attributable to canopy composition

  6. Erodibility of calcareous soils as influenced by land use and intrinsic soil properties in a semiarid region of central Iran.

    Science.gov (United States)

    Ayoubi, Shamsollah; Mokhtari, Javad; Mosaddeghi, Mohammad Reza; Zeraatpisheh, Mojtaba

    2018-03-06

    The most important properties affecting the soil loss and runoff were investigated, and the effects of land use on the soil properties, together with the erodibility indices in a semiarid zone, central Iran, were evaluated. The locations of 100 positions were acquired by cLHS and 0-5-cm surface soil layer samples were used for laboratory analyses from the Borujen Region, Chaharmahal-Va-Bakhtiari Province, central Iran. To measure in situ runoff and soil erodibility of three different land uses comprising dryland, irrigated farming, and rangeland, a portable rainfall simulator was used. The results showed that the high variations (coefficient of variation, CV) were obtained for electrical conductivity (EC), mean weight diameter (MWD), soil organic carbon (SOC), and soil erodibility indices including runoff volume, soil loss, and sediment concentration (CV ~ 43.6-77.4%). Soil erodibility indices showed positive and significant correlations with bulk density and negative correlations with SOC, MWD, clay content, and soil shear strength in the area under investigation. The values of runoff in the dryland, irrigated farming, and rangeland were found 1.5, 28.9, and 58.7 cm 3 ; soil loss in the dryland, irrigated farming, and rangeland were observed 0.25, 2.96, and 76.8 g; and the amount of sediment concentration in the dryland, irrigated farming, and rangeland were found 0.01, 0.11, and 0.15 g cm -3 . It is suggested that further investigations should be carried out on soil erodibility and the potential of sediment yield in various land uses with varying topography and soil properties in semiarid regions of Iran facing the high risk of soil loss.

  7. Regulating mineralization rates of Tithonia diversifolia and Lantana camara prunings to improve phosphorus availability in calcareous soils

    Directory of Open Access Journals (Sweden)

    Y. Nuraini

    2014-01-01

    Full Text Available The effect of mixing of Tithonia diversifolia and Lantana camara prunings to improve synchronization between P released from the prunings with crop demand for P was studied in a laboratory and in a glasshouse. Tithonia diversifolia prunings (Td, Lantana camara prunings (Lc, and farmyard manure (Pk were thoroughly mixed with the proportion (% of dry weight of; 25Td +75 Lc ; 50Td +50 Lc ; 75Td +25 Lc ; 90Lc +10 Pk ; 45Td +45 +10 Lc Pk ; 100Td and 100Lc, and then mixed with 100 g of air-dried soil with a rate equivalent to 100 kg P / ha. Results of the study showed that the pruning mixtures decomposed and mineralized faster than that of Lantana camara pruning only, but slower than that of Tithonia diversifolia pruning only. The amount of P released from the pruning mixtures increased with increasing proportion of Tithonia diversifolia pruning in the mixtures. Increasing proportion of Tithonia diversifolia pruning in the mixture applied to the soil increased the amount of P taken up by maize.

  8. Hydrogeological studies in the water-saturated and unsaturated zone of the calcareous strata in the Wackersdorf region

    International Nuclear Information System (INIS)

    Heinemann, J.M.

    1987-01-01

    The investigation cerves an area of 58.5 km 2 . It is a locally important groundwater reservoir with numerous fountains and waterworks. The investigations were conducted in the unsaturated zone and in the topmost ground-water horizon in the chalky layers. Emphasis is laid on questions of infiltration and groundwater dynamics. The hydrological situation is covered in its entirety, and basic data are collected from field and laboratory tests. (DG) [de

  9. Al 3+ - Ca2+ INTERACTION IN PLANTS GROWING IN ACID SOILS: AL-PHYTOTOXICITY RESPONSE TO CALCAREOUS AMENDMENTS

    OpenAIRE

    Meriño-Gergichevich, C; Alberdi, M; Ivanov, A.G; Reyes-Diaz, M

    2010-01-01

    High aluminum (Al) concentrations as Al3+ represent an important growth and yield limiting factor for crops in acid soils (pH ≤5.5). The most recognized effect of Al-toxicity in plants is observed in roots. However, damages in the upper parts (including stem, leaves and fruits) may also be present. In addition, Al-toxicity triggers an increase in reactive oxygen species (ROS), causing oxidative stress that can damage the roots and chloroplasts, decreasing normal functioning of photo synthetic...

  10. Evaluation of estimated daily intake (EDI) of cadmium and lead for rice (Oryza sativa L.) in calcareous soils.

    Science.gov (United States)

    Chamannejadian, Ali; Sayyad, Gholamabbas; Moezzi, Abdolamir; Jahangiri, Alireza

    2013-04-08

    The excessive amounts of cadmium and lead in food chain can cause health problems for humans and ecosystem. Rice is an important food in human diet. Therefore this study was conducted in order to investigate cadmium and Lead concentrations in seed rice (Oryza saliva) of paddy fields in southwest of Iran. A total of 70 rice seed samples were collected from paddy fields in five regions of Khuzestan province, Southwest Iran, during harvesting time. In the samples cadmium and Lead concentrations were measured. To assess the daily intake of Cadmium and Lead by rice, daily consumption of rice was calculated. The results showed that average concentrations of Cadmium and Lead in rice seeds were 273.6 and 121.8 μg/kg, respectively. Less than 72% of rice seed samples had Cadmium concentrations above 200 μg/kg (i.e. Guide value for cadmium); and less than 3% had Lead concentrations above 150 μg/kg (i.e. Guide value for Lead). The estimated daily intakes of cadmium by the local population was calculated to 0.59 μg/day kg bw, which corresponds to 59% of the tolerable daily intakes (i.e. 1 μg/day kg bw). Eleven out of 70 samples (15.71%) exceed the tolerable daily intakes. The dietary intakes for Lead in the local population ranged from 0.22 to 0.47 μg/day kg bw. Tolerable daily intakes for Lead is 3.6 μg/day kg bw. As a whole, long term consumption of the local rice may bear high risk of heavy metal exposure to the consumer in the study region.

  11. The use of carbon isotopes in the study of groundwater of the Bambui calcareous-central region of Bahia (Brazil)

    International Nuclear Information System (INIS)

    Cabral, F.C.F.

    1978-06-01

    Groundwater of 34 wells and of a spring of the Bambui limestone aquifer, in central Bahia, Brazil, were analized for the 14 C and 13 C content. One sample of soil CO 2 and four of soil organic matter were analized for 13 C. From these data were calculated the 14 C ages of these waters. A major difficulty in the use of radiocarbon in groundwater hydrology is the estimation of the initial 14 C concentration. In many cases, this can be simply determined by the fraction of carbon derived from soil gas, relative to the total carbon dissolved, by the use of Δ 13 C of the soil organic matter, limestone and dissolved carbon in water. This approach does not seem to be completely valid in arid ou semi-arid regions, specially where the pH of the soil is relatively high. In this case, the isotopic composition of the soil water can be determined if the pCO 2 and pH of the soil can be estimated and if the isotopic composition of the soil CO 2 can be known. The final isotopic composition of the groundwater is a combination of the isotopic composition of the soil water and any limestone thereafter dissolved. The 14 C ages of the water samples analized ranged from modern to about 13000 years. The recharge areas of the aquifer are clearly indicated, as the probable underground flow directions. The interpretation of the radiocarbon data is in accord with the hydrologic data. (Author) [pt

  12. Assessing the risk of impact of farming intensification on calcareous grasslands in Europe: a quantitative implementation of the MIRABEL framework

    NARCIS (Netherlands)

    Petit, S.; Elbersen, B.S.

    2006-01-01

    Intensification of farming practices is still a major driver of biodiversity loss in Europe, despite the implementation of policies that aim to reverse this trend. A conceptual framework called MIRABEL was previously developed that enabled a qualitative and expert-based assessment of the impact of

  13. Ojo et al (7)

    African Journals Online (AJOL)

    big timmy

    16, no. 2 (2014). CONSTRAINT MAP FOR LANDFILL SITE SELECTION IN AKURE METROPOLIS, ... One of the major problems in urban areas is the ... micaceous impermeable poor water discharging ..... Delineating Limits of Polluted Surface.

  14. depositional framework and stratigraphy of the konshisha area ...

    African Journals Online (AJOL)

    Okwudiri Aloysius Anyiam, Department of Geology, University of Nigeria, Nsukka, Nigeria. .... (b) Limestone bed with fossilized shells at L/08/Meelem (scale: pen = 18cm) (c) Limestone ..... Turonian times, with the deposition of the micaceous.

  15. Nineteen-year time-series sediment trap study of Coccolithus pelagicus and Emiliania huxleyi (calcareous nannoplankton) fluxes in the Bering Sea and subarctic Pacific Ocean

    Science.gov (United States)

    Tsutsui, Hideto; Takahashi, Kozo; Asahi, Hirofumi; Jordan, Richard W.; Nishida, Shiro; Nishiwaki, Niichi; Yamamoto, Sumito

    2016-03-01

    Coccolithophore fluxes at two sediment trap stations, Station AB in the Bering Sea and Station SA in the subarctic Pacific Ocean, were studied over a nineteen-year (August 1990-July 2009) interval. Two major species, Coccolithus pelagicus and Emiliania huxleyi, occur at both stations, with Gephyrocapsa oceanica, Umbilicosphaera sibogae, Braarudosphaera bigelowii, and Syracosphaera spp. as minor components. The mean coccolithophore fluxes at Stations AB and SA increased from 28.9×106 m2 d-1 and 61.9×106 m2 d-1 in 1990-1999 to 54.4×106 m2 d-1 and 130.2×106 m2 d-1 in 2002-2009, respectively. Furthermore, in late 1999 to early 2000, there was a significant shift in the most dominant species from E. huxleyi to C. pelagicus. High abundances of E. huxleyi correspond to the positive mode of the Pacific Decadal Oscillation (PDO), while those of C. pelagicus respond to the PDO negative mode and are related to water temperature changes at huxleyi. At both stations the mean seawater temperature in the top 45 m from August to October increased ca. 1 °C with linear recurrence from 1990 to 2008. The coccosphere fluxes after Year 2000 at Stations AB and SA, and the shift in species dominance, may have been influenced by this warming.

  16. The effect of brown coal on the decrease in the content of mobile forms of copper and lead in ordinary calcareous chernozem

    Energy Technology Data Exchange (ETDEWEB)

    Bezuglova, O.S.; Ignatenko, E.L.; Morozov, I.V.; Shevchenko, I.D. [Rostov State University, Rostov na Donu (Russian Federation)

    1996-09-01

    Data on the use of brown coal as a soil detoxicant are presented. Purification of soil from heavy metals with brown coal depends on its sorptive properties and the ability of coal-derived humic acids to bind heavy metals into low mobile complexes. The effect of brown coal on the use of mobile copper by soil microorganisms leading to the enhancement of biological activity in chernozems is shown.

  17. FACIES, MICROFOSSILS (SMALLER FORAMINIFERS, CALCAREOUS ALGAE AND BIOSTRATIGRAPHY OF THE HUECO GROUP, DOÑA ANA MOUNTAINS, SOUTHERN NEW MEXICO, USA

    Directory of Open Access Journals (Sweden)

    KARL KRAINER

    2009-03-01

    Full Text Available The Lower Permian Hueco Group of the Doña Ana Mountains (south-central New Mexico, USA is studied in three sections (A, B, C located east of Leasburg, Doña Ana County. Regionally, the Hueco Group has been subdivided into four formations termed Shalem Colony, Community Pit, Robledo Mountains and Apache Dam formations; the lower three are exposed in the Doña Ana Mountains. The succession shows a shallowing upward trend from dominantly shallow, open marine conditions (Shalem Colony Fm to increasingly restricted marine environments (Community Pit Fm and siliciclastic influx (Robledo Mountains Formation. Sedimentation, particularly siliciclastic influx, was mainly controlled by reactivation of basement uplifts during the last pulses of the Ancestral Rocky Mountains deformation. The microfossils and microfacies of the two first formations are studied in detail here. The Shalem Colony Formation can be divided into a lower biozone with Triticites pinguis, which is Newwellian (latest Pennsylvanian, early Wolfcampian in age, and an upper division characterized by the first occurrence of Geinitzina, and lower-middle Asselian (late early Wolfcampian in age. By comparison with the subdivisions of the Carnic Alps (Austria, the Community Pit Formation is characterized as Sakmarian (middle Wolfcampian in age due to the first occurrence of the genus Pseudovermiporella, and its probable complete phylogeny from Hedraites. The late Asselian is restricted to the uppermost part of the Shalem Colony and lowermost part of the Community Pit Formation. Due to the occurrence of Pseudoreichelina the Robledo Mountains Formation is dated as Artinskian (late Wolfcampian. Some bioconstructions of Archaeolithophyllum are emphasized, as well as some species of foraminifers-globivalvulinids, Miliolata and Nodosariata. 

  18. The use of chemical and isotopic data as indicators of the origin of waters and dissolved salts in the Bambui calcareous aquifer (Bahia-Brazil)

    International Nuclear Information System (INIS)

    Siqueira, A.F.

    1978-10-01

    Samples of 25 wells located in the Bambui limestone aquifer in the region of Irece - Bahia, have been analised for the isotopic ratio 18 O/ 16 O and the major chemical species Ca, Mg, Na, K, Cl, SO 4 and bicarbonate. The oxygen-18 data have been found to range between -2,62/00(in a thousand) to -6,66/00(in a thousand) relative to the universal Standard Mean Ocean Water (SMOW) and are compared with the values of the precipitation in the localities of Jacobina and Lencois (meteorological stations nearby) and with the values of the groundwater in sedimentary basins in northeastern Brazil. The comparison suggests that aquifer system is recharged by precipitation originated in northeastern Brazil, instead of originating on coast of Bahia, east of the area. Furthermore, the waters in aquifer are not found homogenized, having widely varying 18 O and chemical composition and being of different ages. The strong correlation between the observations Ca, Mg, Na, Cl and TDS (total dissolved solids) suggests an aerosol origin of salts, not excluding the hypothesis of dissolution of rock, which concentrations. The comparison of characteristic ratios Mg/Ca, SO 4 /Cl and (Cl-Na)/Cl, a Piper diagrama and a dendrogram established by cluster analysis, indicates that the wells may be separated in to two groups according to the isotopic or geochemical environment to which they belong. These groups may represent the differents sources of salt proposed, one being from the limestone, the other having come from aerosols. (Author) [pt

  19. How a Sphagnum fuscum-dominated bog changed into a calcareous fen: the unique Holocene history of a Slovak spring-fed mire

    Czech Academy of Sciences Publication Activity Database

    Hájková, Petra; Grootjans, A.B.; Lamentowicz, M.; Rybníčková, E.; Madaras, M.; Opravilová, V.; Michaelis, D.; Hájek, Michal; Joosten, H.; Wolejko, L.

    2012-01-01

    Roč. 27, č. 3 (2012), s. 233-243 ISSN 0267-8179 Institutional research plan: CEZ:AV0Z60050516 Institutional support: RVO:67985939 Keywords : Holocene * succession * mire Subject RIV: EF - Botanics Impact factor: 2.939, year: 2012

  20. Species richness and above-ground biomass of poor and calcareous spring fens in the flysch West Carpatians, and their relationships to water and soil chemistry

    Czech Academy of Sciences Publication Activity Database

    Hájková, Petra; Hájek, Michal

    2003-01-01

    Roč. 75, - (2003), s. 271-287 ISSN 0032-7786 R&D Projects: GA ČR GA206/99/1240; GA AV ČR KSK6005114 Institutional research plan: CEZ:AV0Z6005908 Keywords : bryophytes * Central Europe * diversity Subject RIV: EF - Botanics

  1. Effect of Plant Growth Promoting Rhizobacteria on the Concentration and Uptake of Macro Nutrients by Corn in a Cd-contaminated Calcareous Soil under Drought Stress

    OpenAIRE

    shahrzad karami; mehdi zarei; jafar yasrebi; najafali karimian; s.Ali Akbar Moosavi

    2017-01-01

    Introduction: Heavy metals such as cadmium (Cd) are found naturally in soils, but their amount can be changed by human activities. The study of the uptake and accumulation of heavy metals by plants is done in order to prevent their threats on human and animal’s health.Cadmium is a toxic element for living organisms. Cadmium competes with many of nutrients to be absorbed by the plant and interferes with their biological roles. Water stress affects the cell structure and the food is diverted fr...

  2. Characterization of non-calcareous 'thin' red clay from south-eastern Brazil: applicability in wall tile manufacture

    Energy Technology Data Exchange (ETDEWEB)

    Sousa, S.J.G.; Holanda, J.N.F., E-mail: sidnei_rjsousa@yahoo.com.br, E-mail: holanda@uenf.br [Grupo de Materiais Ceramicos - LAMAV-CCT, Universidade Estadual do Norte Fluminense Darcy Ribeiro, Campos dos Goytacazes, RJ (Brazil)

    2012-04-15

    In this work the use of 'thin' red clay from south-eastern Brazil (Campos dos Goytacazes, RJ) as raw material for the manufacture of wall tile was investigated. A wide range of characterization techniques was employed, including X-ray diffraction (XRD), X-ray fluorescence (XRF), scanning electron microscopy (SEM), grain-size analysis, and thermogravimetric analysis. The wall tile body was prepared by the dry process. The tile pieces were uniaxially pressed and fired between 1080 - 1180 deg C using a fast-firing cycle. The following technological properties were determined: linear shrinkage, water absorption, apparent density, and flexural strength. The development of the microstructure was followed by SEM and XRD analyses. It was found that the 'thin' red clay is kaolinitic type containing a substantial amount of quartz. The results also showed that the 'thin' red clay could be used in the manufacture of wall tiles, as they present properties compatible with those specified for class BIII of ISO 13006 standard. (author)

  3. Overview of the Plio-Pleistocene geology of Rhodes, Greece. Lithology, calcareous nannofossil biostratigraphy, and sampling of the Kallithea Bay section

    DEFF Research Database (Denmark)

    Thomsen, Erik; Rasmussen, Tine Lander; Hastrup, Annette

    2005-01-01

    The Kallithea Bay section on the east coast of Rhodes represents an overall transgressive succession ranging from fluviatile and brackish water gravel at the base to deep-water marl at the top. The brackish water and near-shore deposits are assigned to the Kritika Formation, while the deep-water ...

  4. The last 1.2 Myr of the Cretaceous in the southwestern Tethys (Elles, Tunisia): orbital calibration, climate change and calcareous nannofossil palaeoecological changes

    DEFF Research Database (Denmark)

    Thibault, Nicolas Rudolph; Galbrun, Bruno; Gardin, Silvia

    2014-01-01

    An integrated study of magnetic mass susceptibility (MS), bulk stable isotopes and nannofossil paleoecological changes has been performed on the late Maastrichtian of the Elles section, central Tunisia, spanning the last 1.2 Myr of the Cretaceous. A cyclostratigraphic analysis of MS variations re...

  5. The Fractionation of Some Heavy Metals in Calcareous Soils Affected by Land Uses of Central Area of Zanjan Provine (Northwest of Iran

    Directory of Open Access Journals (Sweden)

    Ali Afshari

    2017-01-01

    Full Text Available Introduction: Heavy metals are found to be one of the major environmental hazardous contaminants, for human health, animal life, air quality and other components of environment. They can affect geochemical cycles and accumulate in animal tissues since physical processes are not able to remove them, so they are consistent in long term. The analysis of the total concentration of heavy metals in soil may provide information about soils enrichment but in general, it is widely used to determine the potential mobility of heavy metals in environmental behavior under chemical forms of metals in soils. Heavy metals existat several phases including water-soluble, exchangeable, bounded to organic matter, bounded to carbonates, bounded to Fe-Mn oxides, secondary clay minerals and residual fraction within primary minerals network. There is a dynamic equilibrium between different fractions of elements in soil. The main objectives of the present study were a The analysis of the total concentration of heavy metals such as Fe, Mn, Ni, Cr, Co, Pb, Zn, Cd and Cu and b The fractionations of heavy metals and identification of controlling factors to distribution and behavior of heavy metals in soils at different land uses. Materials and Methods: The study was performed at central area of Zanjan province (Iran. The study area was over 2000 km2 in coordinates 20´ 36° to 41´ 36° E and 19´ 48° to 53´ 48° N. The average altitudes were over 1500 meters above sea level. The major land uses of the study area included agriculture (AG, rangeland (RA and urban (UR. Sample collection was done based on the random grid method in August 2011. Surface soil samples (0-10 cm depth were taken from grid centers included 137, 77 and 27 samples from AG, RA and UR land uses, respectively. The samples were digested in Nitric acid 5 normal (Sposito et al., 1982 and total concentration of Pb, Zn, Ni, Mn, Cu, Cr, Fe and Co were measured by Perkin-Elmer: AA 200 atomic absorption instrument and cadmium was measured by atomic absorption equipped with Rayleigh: WF-1E graphite furnace. 75 soil samples were selected, DTPA-extraction and sequential extraction were performed and physiochemical characteristics of these samples analyzed. To extract the metals by DTPA, the method developed by Lindsay and Norvell, (1978 was used and sequential extraction was done by Tessier et al., (1979 method. All statistical parameters were calculated using SPSS 16.0 software, and mean comparison (mean separation was carried out using Duncan test at probability level of 5%. Results and Discussion: The results indicated that heavy metals concentrations and patterns were evidently affected by different land uses. Co concentration was between 17.0 – 35.7 mg/kg and had the lowest total coefficient of variation (14%. The maximum total Cr and Ni values were measured in AG land use (26.1 and 52.6 mg/kg, respectively and lowest was in UR land use (17.0 and 37.2 mg/kg, respectively. The highest total average value of Mn was found in RA (698.9 mg/kg and the lowest in UR (629.1mg/kg land use. The highest Fe concentrations were measured in AG and RA land uses (17.2 and 17.0 g/kg, respectively and the lowest in UR land use (14.0 g/kg. The maximum Concentration of total Cd was observed in UR land use (2.47 mg/kg and its minimum values were found in RA and AG (0.83 and 0.75 mg/kg, respectively in the study area. In UR land use, Cu and Zn were more significant than AG and RA land uses. Pb variation was the same as Zn so that its increased concentration was found in urban land use (90.2 to 1357.5 on average 220.1 mg/kg. The highest Pb values were measured in UR land use (220 mg/kg while the lowest concentrations were found in RA and AG land uses (80.6 and 69.0 mg/kg, respectively. Different elements showed various fractional distribution in different land uses. The highest Co percentage was related to residual fraction at all land uses, with values up to 48.4%, 54.0% and 48.1% in AG, RA and UR land uses, respectively. Ni fractionation had approximately the same pattern with Co in all factions and land uses, except exchangeable fraction of Ni that showed the lowest percentage in all land uses. The dominant fraction of Cu was residual fraction with the amounts of 73.3% 76.0% and 61.9% in AG, RA and UR land uses, respectively. The second dominant fraction in UR and AG land uses was related to that was bounded to OM, with 16.5% and 10.1%, respectively. Zn distribution in the AG and RA land uses had the same trend: Residual>bounded to Fe-Mn oxides>bounded to OM>bounded to carbonate>exchangeable fraction. Whereas, Zn distribution showed different trend in UR land use as bounded to Fe-Mn oxides>residual>bounded to carbonate>bounded to OM>exchangeable fraction. Pb distribution was different in each land use. Pb showed similar distribution to Zn in UR. In AG and RA land uses residual fraction of Pb was measured as highest value while other fractions of Pb had these distributions: Pb bounded to carbonate>bounded to Fe-Mn oxides>exchangeable >bounded to OM fraction in AG land use and Pb bounded to Fe-Mn oxides>bounded to OM>bounded to carbonate>exchangeable fraction in RA land use. Conclusion: Based on the results of this study, Cr, Co, Ni, Mn and Fe magnitudes are uneven in soils. The total heavy metal concentrations fractionation can provide information on the contaminant metals sources. High levels of exchangeable fractions, acid soluble and easily reducible perhaps indicates anthropogenic activities. Naturally, Chemicals are associated to resistant soil fractions such as oxy hydroxides, organic matter and sulfides. In soil fractionation, the contribution of each fraction in soil was a function of metal type and land uses. Those metals were affected by anthropogenic activities such as lead, zinc, and partly copper, showed the highest percentage in the fraction that influenced by external input sources. Those were characterized by lithogenic origin (cobalt and nickel was mainly found to be highest in residual fraction. However, in all metals, those fractions affected by anthropogenic activities (non-resistant fractions were much more in urban land use than agriculture and rangeland ones.

  6. Distribution of foraminifera and calcareous nannoplankton in quaternary sediments of the Eastern Angola Basin in response to climatic and oceanic fluctuations

    NARCIS (Netherlands)

    Zachariasse, W.J.; Schmidt, R.R.; Leeuwen, R.J.W. van

    1984-01-01

    The impact of the Zaire River on the oceanic environment is clearly illustrated in the surface sediments by anomalously high carbonate dissolution rates over a large area off the river mouth. This anomaly results from the high supply of terrestrial organic matter brought into the Angola Basin by the

  7. Lithofacies Architecturing and Hydrocarbon Reservoir Potential of Lumshiwal Formation: Surghar Range, Trans-Indus Ranges, North Pakistan

    Directory of Open Access Journals (Sweden)

    Iftikhar Alam

    2015-12-01

    Full Text Available Western environs of the Indo-Pak Plate are comprised of thick Mesozoic sedimentary sequence and extensively extended toward Trans-Indus Salt ranges of North Pakistan. This sequence consists of detrital clastic sediments in the lower level and shallow to deep marine sediments in the upper level. In the Trans-Indus Salt ranges the Lumshiwal Formation represents the transitional level of the lower Cretaceous sequence. In Surghar Range the lower part of formation is composed of cyclic alteration of clayey, silty, very fine grained greenish gray, glauconitic sandstone to rusty brownish gray sandstone. The middle part of formation is comprised of thick bedded to massive, cliff forming, sugary texture, whitish to light yellowish gray occasionally rusty brownish gray medium to coarse grained, moderate to well cemented sandstone. The upper part is comprised of feldspathic, ferruginous, weathering yellowish brown, rusty brown to light gray with locally calcareous sandstone beds. The sandstone is reddish to brownish gray, coarse to granules texture, moderately cemented thick bedded to massive. Total thickness of the formation is 220m at Baroch Nala section 230m in Karandi section at a dip of 60°. Along trend lithological variations and diversified primary sedimentary structures which classifies fifteen different sub-lithofacie in Lumshiwal. Middle and upper parts of the formation show massive to thick, current bedded deposits. Lithofacies analysis revealed that the Lumshiwal Formation was deposited in shallow marine for the lower cyclic part to transitionally prodeltaic to deltaic for the middle to upper part respectively. High silica contents in the upper part compare to the middle and lower part of the formation. On the basis of high silica and low alumina with other low fractions of rock fragments, the sandstone is categorized into quartzarenite, sub-litharenite and sub-arkose. Cross beds in the middle and upper parts of formation indicate west to east

  8. A Unique Laboratory to Explore Soil-Wine Relationships, North Canterbury, New Zealand

    Science.gov (United States)

    Harrison, R.; Tomasino, E.; Tonkin, P.; Webb, T.; Burns, S. F.; Weersing, M.

    2012-12-01

    The special character of North Canterbury is a reflection of its geological history - a region of oblique crustal convergence forming northeast striking folds, creating hill, valley and basin topography. Cretaceous to Tertiary glauconitic sediments, limestones, sandstones and weathered conglomerates overlie basement greywacke sandstones and siltstones. During the late Quaternary, erosion infilled valleys with locally sourced sediments, and basins with greywacke alluvium. Calcareous and noncalcareous loess mantles are locally sourced. Detailed soil mapping of vineyards planted between 1980 and 2000 reveal bedrock and colluvial hill slopes with clayey Haplustolls and Argiustolls, fans with deep silty Hapustalfs and terraces with deep alluvium forming clayey Calciusterts and gravels forming Haplustepts. Definitions of terroir variously include physical attributes such as climate, landscapes, soils and vines, together with cultural traditions represented by grape varieties and systems for canopy management, which come together in particular sensory attributes displayed by certain wines. We have recently begun to explore terroir in the context of New Zealand Pinot Noir (the variety considered by many as most able to communicate details of local geography and site). The assessment of wine sensory attributes is not a trivial task. Our experience is that scale is an important influence as ferment size decreases. We recommend the use of commercially produced wines for such studies. Our work has been carried out using statistically valid designs with expert but untrained panelists. In these circumstances the meaning ascribed to particular attributes may vary between panelists but there is evidence to support the contention that expert panelists tend to share a standard vocabulary and are likely to be familiar with appropriate conceptual models of the wines that allow their differentiation. Our results confirm that Pinot Noir wines from climatically differing regions of New

  9. Geotechnical and environmental problems related to shales in the ...

    African Journals Online (AJOL)

    EJIRO

    Six (6) samples of shale and five (5) water samples from hand-dug wells and boreholes, from different locations within the ... dark grey in colour, blocky, and non-micaceous in most locations. ..... Advances in water treatment and environmental ...

  10. Are Majhgawan–Hinota pipe rocks truly group-I kimberlite?

    Indian Academy of Sciences (India)

    and Paul 1989; Halder and Ghosh 1978, 1981) to designate the rocks as micaceous kimberlite/basaltic kimberlite and kimberlite breccia. Kent et al (1998) preferred to call the ... from Damodar Valley, eastern India (Kent et al 1998). The majority of the ..... 27: Average (6 analyses) Leucite Hill madupitic lamproite. 28: Olivine ...

  11. pdf2xml

    International Development Research Centre (IDRC) Digital Library (Canada)

    Leur croissance a obligé certaines d'entre elles ( Rio de Janeiro, Maceió, Recife ...... gneiss, divers types de migmatites et par des intrusions granitiques isolées. ...... de minéraux micacés ( surtout muscovite et biotite, mais également sericite, ...

  12. Relationships between contourite deposition, climate and slope instability: new insights from the Demerara Plateau (French Guyana)

    Science.gov (United States)

    Tallobre, C.; Bassetti, M. A.; Loncke, L.; Giresse, P.; Bayon, G.; Buscail, R.

    2015-12-01

    A Contourite Depositional System (CDS) has been described at the Demerara Plateau (DP) based on seismic investigations, but little is known about the mechanisms of associated sediment deposition and its interaction with past deep ocean circulation patterns (e.g. bottom current velocity) and bottom morphology related to ancient event of slope instability. The new seismic and bathymetric data recently acquired allow describing in details the CDS on the DP. Erosional and syn-sedimentary features on the seafloor (comet tail, « longitudinal waves », contourite drifts and moats) have been observed, helping to constrain the sedimentary processes at the origin of the CDS construction. Also, the recovery and multi-proxy analysis of sediment cores allows the characterization of sedimentary environments and possible relation with climate forcing. These sediment cores are characterized by the presence of several beds rich in glauconite grains. Glauconite can form at the sediment/water interface by winnowing effect that prevent sediment deposition and increase the residence time at the seafloor. Under strong winnowing conditions, glauconite grains can develop at several stages of maturity. We observed that the residence time and hence the maturity of glauconite is reflected by the color changes (light to dark green), the presence of crack on grains, the formation of (secondary) glauconite lamellae and decrease of grain porosity. A chronological framework (based on radiocarbon dates and δ18O variations) of contourite sequences at the studied location indicates correlation with grain-size parameters (sortable silt) and allows one to further constrain their dynamics through time. The combination of these proxies allows us to estimate and understand the evolution and the impact of the bottom current on sedimentation on the DP during the last 80 ky. These results show the potentiality of the glauconite study to estimate the relative variation of bottom current velocity at margins.

  13. Efecto de extractos de la esponja calcarea Leucetta aff. floridana sobre el ciclo de líneas celulares leucemoides Effect of extracts from the calcareous sponge Leucetta aff. floridana on the cell cycle of leukemoid cell lines

    Directory of Open Access Journals (Sweden)

    Diana Margarita Márquez Fernández

    2012-12-01

    Full Text Available Introducción: la esponja Leucetta aff. floridana produce compuestos con actividad antiproliferativa diferencial en células tumorales de pulmón y mama, la cual no ha sido explorada en otras líneas tumorales y se desconoce si su potencial antiproliferativo está relacionado con la progresión de células a través del ciclo celular. Objetivo: evaluar el potencial antiproliferativo, anticlonogénico y el efecto sobre el ciclo celular de los extractos hexánico y metanólico de la esponja Leucetta aff. floridana del Caribe colombiano en las líneas celulares leucemoides Jurkat y K562. Métodos: la viabilidad y proliferación celular se determinaron mediante el ensayo de azul de tripano a 0, 24, 48, 72 y 96 h. La eficiencia de clonación y el efecto sobre el ciclo celular se evaluaron a 10 y 100 µg/mL. Los datos se analizaron usando ANOVA multifactorial y la prueba Tukey. Resultados: el extracto hexánico presentó actividad antiproliferativa en ambas líneas celulares siendo Jurkat más sensible que K562, lo cual se corroboró con los ensayos de clonogenicidad. Este extracto también mostró un efecto de acumulación de células Sub-G1 dependiente de la dosis, el cual fue diferencial entre las dos líneas celulares. La duración del tratamiento con el extracto hexánico no fue significativa para las células K562 pero sí para la línea celular Jurkat. Además, el porcentaje de acumulación de las células Sub-G1 fue mayor para células K562 comparado con Jurkat. El extracto metanólico presentó un efecto antiproliferativo similar al hexánico, pero fue más potente con la menor concentración (10 µg/mL en la clonogenicidad de K562. El efecto sobre el ciclo celular, también fue similar al hexánico, pero la duración del tratamiento no fue significativa en la acumulación de células en Sub-G1. Conclusiones: los resultados muestran el potencial diferencial de los extractos sobre el ciclo celular de las líneas leucemoides evaluadas.Introduction: Leucetta aff. floridana sponge produces compounds with differential antiproliferative activity on lung and breast cancer. Nevertheless, this activity in other tumour cell lines has not yet been tested and it remains unknown whether its antiproliferative potential is correlated with the cell progression through cell cycle or not. Objective: To evaluate the antiproliferative and anticlonogenic potential and the effect of methanolic and hexanic extracts of sponge L. aff. floridana from the Colombian Caribbean region on the cell cycle of Jurkat and K562 leukemoid cell lines. Methods: The viability and antiproliferative effect were determined using trypan blue assay at 0, 24, 48, 72 and 96 hours. Clongenicity and effect on cell cycle were assayed at 10 and 100 µg/mL Data obtained were analyzed using multifactorial ANOVA and Tukey's test. Results: The hexanic extract presented antiproliferative activity in both Jurkat and K652 cell lines; Jurkat being more sensitive than K652. These results were confirmed by clongenicity assays. The hexanic extract also showed its effect on the dose-dependent accumulation of Sub-G1 cells, although it was different in the two cell lines. The duration of the treatment with the hexanic extract was not significant for K562 cell line, but it was for Jurkat cells. Additionally, the percentage of cell accumulation in Sub-G1 was higher in K562 than in Jurkat cells. The methanolic extract showed antiproliferative effect similar to that of the hexanic extract, but more potent at the lowest concentration (10 µg/mL in K652 cell line clonegenicity. The effect on cell cycle was also similar to that of the hexanic extract, but in this case the duration of treatment was not significant in the cell accumulation in Sub-G1. Conclusions: Altogether these results show the differential potential of the extracts on the cell cycle of the evaluated leukemoid cell lines.

  14. Etude de l’altération de la calcarénite des monuments de Rabat : Influence de la Pollution Atmosphérique et des Aérosols Marins

    Directory of Open Access Journals (Sweden)

    Zaouia Nouhad

    2014-04-01

    Le but du présent travail est de constituer une base de données pour orienter les recherches ultérieures sur la problématique de la conservation du patrimoine bâti et optimiser le choix des matériaux de remplacement, tout en prenant en compte tous les mécanismes et démarches nécessaires pour une meilleure protection dans lecadre d’un développement urbain en perpétuelle expansion.

  15. Parameters controlling fracturing distribution: example of an Upper Jurassic marly-calcareous formation (eastern Paris Basin); Parametres controlant la distribution de la fracturation: exemple dans une serie marno-calcaire du Jurassique superieur (Est du bassin de Paris)

    Energy Technology Data Exchange (ETDEWEB)

    Andre, G.; Rebours, H.; Wileveau, Y. [Agence Nationale pour la Gestion des Dechets Radioactifs (ANDRA), Laboratoire de recherche souterrain de Meuse/Haute-Marne, 55 - Bure (France); Proudhon, B. [GEO.TER, 34 - Clapiers (France)

    2006-10-15

    Study of fractures along a 490-m vertical section of marl/limestone alternations in the Upper Jurassic (Meuse/Haute-Marne underground research laboratory-eastern Paris Basin) reveals their organization and the different states of palaeo-stress. Type and extension of tectonic structures seem to be controlled principally by lithology and secondary by depth. Also, it appears deviations of Alpine palaeo-stresses between Kimmeridgian and Oxfordian formations. These deviations are related to the presence of marl/limestone contacts. The vertical evolution of current horizontal maximum stress shows a similar behaviour, with deviations at the walls of Callovo-Oxfordian argilites. These results allow us to point out and to discuss the impact of lithology, rheology and depth on fracturing occurrence and distribution. Furthermore, this study suggests the role of Callovo-Oxfordian as a barrier for fracture development between the limestones of Dogger and Oxfordian formations. (authors)

  16. Edafologic characteristics for the vulnerability of ground water by pollution under the calcaric fluvisols; Caracteristicas edaficas condicionantes de la vulnerabilidad a la contaminacion de las aguas subterraneas situadas bajo fluvisoles calcareos

    Energy Technology Data Exchange (ETDEWEB)

    Moreno Merino, L.; Gonzalez Huecas, C.; Lopez Lafuente, A. [Departamento de Edafologia, Universidad Complutense de Madrid, Madrid (Spain)

    1995-08-01

    A study of vulnerability of ground water based on an pedagogical view of the problem is presented. To do this, the study of one area with a piezo metric level close enough to the surface is selected, in such degree that the purification processes will take part in the greatest zone of the vadose zone. Profiles selected were studied under classical techniques of edafologic characterization, but the interpretation is newness, focusing always the behaviour of how ground water is protected against contaminants potentially aggressive, instead the study of genetic identification pf profiles or the study of genetic identification of profiles or the study of agricultural finess. 27 refs.

  17. Revised tuning of Ocean Drilling Program Site 964 and KC01B (Mediterranean) and implications for the delta 0-18, tephra, calcareous nannofossil, and geomagnetic reversal chronologies of the past 1.1 Myr

    NARCIS (Netherlands)

    Lourens, L.J.

    2004-01-01

    High-resolution color reflectance records of KC01 and KC01B (Calabrian Ridge, Ionian Sea) are presented and compared with a modified spliced high-resolution color reflectance record of Ocean Drilling Program (ODP) Site 964. This comparison revealed that KC01B is characterized by intensive

  18. Bedrock geologic map of the Miles Pond and Concord quadrangles, Essex and Caledonia Counties, Vermont, and Grafton County, New Hampshire

    Science.gov (United States)

    Rankin, Douglas W.

    2018-04-20

    Highlandcroft Granodiorite and Joslin Turn tonalite plutons intruded during the Middle to Late Ordovician.West of the Monroe fault, the Connecticut Valley-Gaspé trough consists of the Silurian and Devonian Waits River and Gile Mountain Formations. The Waits River Formation is a carbonaceous muscovite-biotite-quartz (±garnet) phyllite containing abundant beds of micaceous quartz-rich limestone. The Gile Mountain Formation consists of interlayered metasandstone and graphitic (and commonly sulfidic) slate, along with minor calcareous metasandstone and ironstone. Graded bedding is common in the Gile Mountain Formation. Rocks of the Devonian New Hampshire Plutonic Suite intruded as plutons, dikes, and sills. The largest of these is the Victory pluton, which consists of weakly foliated, biotite granite and granodiorite. The Victory pluton also intruded a large part of the Albee Formation to the north.This report consists of a geologic map and an online geographic information systems database that includes contacts of bedrock geologic units, faults, outcrops, and structural geologic information. The geologic map is intended to serve as a foundation for applying geologic information to problems involving land use decisions, groundwater availability and quality, earth resources such as natural aggregate for construction, assessment of natural hazards, and engineering and environmental studies for waste disposal sites and construction projects.

  19. Electrodialytic Soil Remediation. Improved conditions and acceleration of the process by addition of desorbing agents to the soil

    DEFF Research Database (Denmark)

    Ottosen, Lisbeth M.; Hansen, Henrik; Hansen, Lene

    1998-01-01

    The principel of electrodialytic soil remediation was improved when ammonia was added to a calcareous copper polluted soil......The principel of electrodialytic soil remediation was improved when ammonia was added to a calcareous copper polluted soil...

  20. Fish remains from Miocene beds of Višnja vas near Vojnik, Slovenia

    Directory of Open Access Journals (Sweden)

    Aleš Šoster

    2013-06-01

    Full Text Available This paper discusses fossil teeth of sharks (Elasmobranchii, Neoselachii and porgies (Teleostei, Sparidae fromthe Miocene glauconite sandstones of Vi{nja vas near Vojnik. The remains of fish teeth, mostly tooth crowns, belongto cartilaginous fishes of the genera Notorynchus, Carcharias, Carcharoides, Isurus and Cosmopolitodus and to abony fish genus Pagrus.

  1. Moessbauer characteristics of glauconitisation

    International Nuclear Information System (INIS)

    Kuzmann, E.; Weiszburg, T. G.; Toth, E.; Garg, V. K.

    2008-01-01

    57 Fe Moessbauer spectroscopy, X-ray diffraction and local (WDX, EDX) and bulk chemical methods (ICP-AES complemented with Fe 2+ titration) were used to study glauconites originating from three sandstone samples (NY1, NY3 and EWT) of the Upper Oligocene Eger Formation (Northern Hungary). The, during glauconitisation, increasing aggregate density and magnetic susceptibility offered a unique possibility to separate grains of different evolutionary stage from the same glauconite population. 57 Fe Moessbauer spectra of both structurally and chemically well characterised glauconite fractions were decomposed into four doublets. Two-two of the doublets were assigned to octahedral Fe 2+ and octahedral Fe 3+ . Fe 2+ /Fe values determined by Moessbauer measurements were used for the calculation of the chemical formula of glauconite samples [including octahedral occupancy (B O ) and octahedral charge (X O ) as well]. The gradual increase of Fe 2+ /Fe was documented with the increase of aggregate density in correlation with the foregoing of glauconitisation. Our results give a quantitative demonstration that octahedral occupancy (B O ) decrease and the substitution of octahedral Al by Fe 2+ are the major processes allowing the interlayer K incorporation during glauconitisation. The systematic crystalchemical evolution as reflected in the systematic changes of the Moessbauer data are discussed in terms of the subsequent steps of glauconitisation.

  2. (late cretaceous), southern benue trough, nigeria

    African Journals Online (AJOL)

    DJFLEX

    upward increase in the number, thickness and angle of dip of cross-beds, typifies shallow marine sandstones. The bipolar-bimodal model of .... depth exceeding 1,300 m where grain boundaries are ... clay and iron-oxide commonly derived from degraded glauconite. a .... accumulation of randomly oriented shells of Exogyra.

  3. The Eocene-Oligocene sedimentary record in the Chesapeake Bay impact structure: Implications for climate and sea-level changes on the western Atlantic margin

    Science.gov (United States)

    Schulte, P.; Wade, B.S.; Kontny, A.; ,

    2009-01-01

    A multidisciplinary investigation of the Eocene-Oligocene transition in the International Continental Scientific Drilling Program (ICDP)-U.S. Geological Survey (USGS) Eyreville core from the Chesapeake Bay impact basin was conducted in order to document environmental changes and sequence stratigraphic setting. Planktonic foraminifera and calcareous nannofossil biostratigraphy indicate that the Eyreville core includes an expanded upper Eocene (Biozones E15 to E16 and NP19/20 to NP21, respectively) and a condensed Oligocene-Miocene (NP24-NN1) sedimentary sequence. The Eocene-Oligocene contact corresponds to a =3-Ma-long hiatus. Eocene- Oligocene sedimentation is dominated by great diversity and varying amounts of detrital and authigenic minerals. Four sedimentary intervals are identified by lithology and mineral content: (1) A 30-m-thick, smectite- and illite-rich interval directly overlies the Exmore Formation, suggesting long-term reworking of impact debris within the Chesapeake Bay impact structure. (2) Subsequently, an increase in kaolinite content suggests erosion from soils developed during late Eocene warm and humid climate in agreement with data derived from other Atlantic sites. However, the kaolinite increase may also be explained by change to a predominant sediment input from outside the Chesapeake Bay impact structure caused by progradation of more proximal facies belts during the highstand systems tract of the late Eocene sequence E10.Spectral analysis based on gamma-ray and magnetic susceptibility logs suggests infl uence of 1.2 Ma low-amplitude oscillation of the obliquity period during the late Eocene. (3) During the latest Eocene (Biozones NP21 and E16), several lithological contacts (clay to clayey silt) occur concomitant with a prominent change in the mineralogical composition with illite as a major component: This lithological change starts close to the Biozone NP19/20-NP21 boundary and may correspond to sequence boundary E10-E11 as observed in

  4. The U-Pb System in Schorlomite from Calcite-Amphobole-Pyroxene Pegmatite of the Afrikanda Complex (Kola Peninsula)

    Science.gov (United States)

    Salnikova, E. B.; Stifeeva, M. V.; Chakhmouradian, A. R.; Glebovitsky, V. A.; Reguir, E. P.

    2018-02-01

    The geochronological U-Pb study of shorlomite from igneous rocks of the alkali-ultramafic Afrikanda massif (Kola Peninsula) was performed. The results demonstrate the reliability of calcium garnet as a mineral for the U-Pb geochronology of a wide range of igneous rocks, i.e., carbonatite, syenite, foidolite, foidite, melilitolite, melilitite, lamprophyres, micaceous kimberlites, etc., and associated rare earth and trace elements (REE, Nb, Zr) mineralization.

  5. Evaluation of Moisture-Cure Urethane Coatings for Compliance with Industry Specifications

    Science.gov (United States)

    2011-12-01

    polyurethane coating with a thermoset binder and micaceous iron oxide pigment reinforcement. Since SSPC paint specifications are designed for zinc ...Outside Coating System No.2 (minimum AWWA OFT 7.5 mils) 1 ct. Corothane I GalvaPac Zinc Primer@ 3.0 mils dft 1 ct. Corothane Iron ox B@ 3.0 mils dft...Substrates Over properly prepared: Ferrous Metal Galvanized Metal Aluminium/Non-Ferrous Metal Ductile Iron Previously Existing Coatings

  6. Geochemistry and mineralogy of recent sediments of Guanabara Bay (NE sector) and its major rivers - Rio de Janeiro State - Brazil

    OpenAIRE

    FARIA, MARCIA DE MELO; SANCHEZ, BRAZ A.

    2001-01-01

    Geochemical and clay mineralogical studies of bottom sediments collected along the Macacu and Caceribu rivers and Guanabara Bay were carried out in order to investigate the relationship between major source areas and recent sediments of the bay. Clay mineralogy includes different groups with selective distribution conditioned by geomorphic features and depositional settings. Micaceous clay minerals are abundant near parent rock in the upper course, whereas kaolinite derived from varied source...

  7. Decreasing of transfer of caesium and strontium radionuclides from soil to vegetation - Use of modified aluminosilicates for decreasing of transfer of caesium and strontium radionuclides from soil to vegetation

    Energy Technology Data Exchange (ETDEWEB)

    Voronina, Anna V.; Blinova, Marina O.; Semenischev, Vladimir S.; Kutergin, Andrey S. [Ural federal university, 620002 Ekaterinburg (Russian Federation)

    2014-07-01

    The method of addition of sorbents to soils is seemed to be the most efficient for decreasing of transfer of radionuclides from soil to vegetation. Using sorbents should possess affinity to natural systems, high specificity and selectivity and also irreversibility of sorption of radionuclides for effective retention of radionuclides as well as to prevent their migration into vegetation and further movement through food chains. Specificity, selectivity and reversibility of sorption of caesium and strontium radionuclides by natural aluminosilicates (glauconite, clinoptilolite) and modified ferrocyanide sorbents based on them was studied in this work. It was shown that the natural glauconite sorbs caesium from tap water with distribution coefficient K{sub d} = 10{sup (3.5±0.1)} mL/g, static exchange capacity of Cs is 11.0 mg/g; it shows lower specificity to strontium: K{sub d} = 10(2.5±0.1) mL/g, static exchange capacity = 9 mg/g. For clinoptilolite these parameters are for caesium K{sub d} = 10(4.4±0.5) mL/g, static exchange capacity 210 mg/g; for strontium K{sub d} = 10(3.5±0.1) mL/g, capacity = 12 mg/g. Ferrocyanide sorbents concentrate caesium radionuclides more effectively: distribution coefficient of Cs from tap water by mixed nickel-potassium ferrocyanide based on glauconite is 10(5.9±1.6) mL/g, static exchange capacity of Cs is (63.0±2.0) mg/g; for mixed nickel-potassium ferrocyanide based on clinoptilolite these characteristics are respectively 10(7.4±1.3) mL/g, 500 mg/g. In case of modified sorbents specificity to strontium remains the same as for natural aluminosilicates. Reversibility of sorption of caesium by natural glauconite and ferrocyanide sorbent was determined as caesium leaching degree from saturated samples. High caesium leaching rates and degrees are typical for natural glauconite irrespective of leachant salinity: total degree of leaching after 35 days of leaching was: mineral water = 63.4%, tap water = 41.6% and rain water = 28.8%. For

  8. Features of phenacite mineralization from the Ural emerald mines

    Directory of Open Access Journals (Sweden)

    M. P. Popov

    2017-09-01

    Full Text Available The authors consider the problems of development of phenacite mineralization at the Ural Emerald Mines, which is rather well developed and described in the Mariinsky (Malyshevsky and Sretensky (Sverdlovsk emerald-beryllium deposits. Phenacite is widespread in many beryllium deposits, but crystals of jewelry quality, with such large sizes as at the Emerald Mines, form rarely. Despite the prescription of the discovery (1833, and because of the rare occurrence of jewelry quality of crystals, and the presence of more expensive and valuable stones – emeralds and alexandrites – in deposits of the Emerald mines, phenacite remains almost unknown in the precious stones market, and especially abroad. Phenacite mineralization mostly occurs in the micaceous veins represented by gray and greenish-gray phlogopite. Distribution of phenacite in the micaceous veins is extremely uneven. Mineralization is typically nesting. High content of phenacite appears in the micaceous veins, mineral composition of which is mostly phlogopite, veins and concretions of beryllium-containing margarite (B-margarite and chlorite. Content of phenacite is low in the micaceous veins that include phlogopite, plagioclase, beryl, fluorite, smoky quartz. At the Sretensky deposit is located a vein that refers to a new type of ore bodies of the chrysoberyl-phenacite composition lying in ultrabasic rocks. Unlike emerald-bearing micaceous veins that have a northwestern spread, the chrysoberyl-phenacite ore bodies are oriented in the near-latitudinal direction and have a northern incidence at an angle of 75°–80°. The most common form of phenacite crystals on the Emerald Mines is rhombohedral and short columned. Crystals have a large number of faces. The usual shapes are a hexagonal prism and rhombohedrons. Twin crystals are common, druses, columnar aggregates, and spherulites are characteristic. Phenacite can be colorless or slightly colored in wine yellow, sometimes pinkish, light

  9. Influence of pore fluid and frequency on elastic properties of greensand as interpreted using NMR data

    DEFF Research Database (Denmark)

    Hossain, Zakir; Mukerj, Tapan; Fabricius, Ida Lykke

    2011-01-01

    dispersion. However, Biot’s theory does not fully explain the frequency dispersion of sedimentary rocks. Greensands are composed of a mixture of quartz and micro-porous glauconite grains. In greensand, it is possible that the contrast between flow in macro-pores and micro-pores within glauconites gives rise....... Biot’s critical frequency and NMR (nuclear magnetic resonance) T2 spectrum were combined to describe the differences in fluid flow within macro-pores and within micro-pores. NMR data show that Biot’s flow should occur only in large pores in the greensand while, Biot’s flow should not occur in micro-pores....... Differences of fluid flow in macro-pores and micro-pores pores are described as high frequency squirt flow in greensand....

  10. Petrographic characteristic of the sandstones of the upper paleocene-middle eocene aged in the Yildizli-Aydinkent (Ereğli-Konya area

    Directory of Open Access Journals (Sweden)

    A. Müjdat Özkan

    2002-03-01

    Full Text Available In the study area, Upper Paleocene - Middle Eocene aged Halkapınar formation, was formed in a shallow and deep marine environment. The lithologies of this formation are medium - thick bedded conglomerate, thin - thick bedded sandstone, thin - very thick bedded shale, thin - medium bedded marl with chert nodules and bands. In addition olistolithes of ophiolitic melange are found at the top of the sandstones, which includes basalt interbands. Yellowish gray, greenish gray, beige, gray colored sandstones include some sedimentary structures, namely ripple - marks, graded bedding, laminate, convolute lamination, current ripple, tool marks. Constituents of the sandstones are quartz, plagioclase, sanidine, orthoclase, fragments of sedimentary and methamorphic rocks, biotite, muscovite, opaque mineral and glauconite. The sandstones, which are not matured in terms of mineralogy and texture, are mainly cemented by calcite, clay matrix and minor iron oxide and glauconite matrix. The sandstones are named lithic arenite, lithic graywacke, feldspathic litharenite and litharenite.

  11. Moessbauer spectroscopy of iron in clay minerals

    International Nuclear Information System (INIS)

    Raclavsky, K.; Sitek, J.; Lipka, J.

    1975-01-01

    Selected pure clay minerals predominantly of Czechoslovak origin were studied, such as montmorillonite, nontronite, beidellite, glauconite, seladonite, illite, vermiculite, saponite, palygorskite, goethite. Moessbauer measurements were performed at room temperature with a 57 Co in Pd source. The spectra were fitted by the least square method. The parameters of the measured Moessbauer spectra are given. The values of isomer shifts, quadrupole splittings and line widths were obtained with an error of +- 0.03 mm/sec. (Z.S.)

  12. Formation mechanisms and sequence response of authigenic grain-coating chlorite: evidence from the Upper Triassic Xujiahe Formation in the southern Sichuan Basin, China

    Directory of Open Access Journals (Sweden)

    Yu Yu

    2016-11-01

    Full Text Available Abstract Authigenic grain-coating chlorite is widely distributed in the clastic rocks of many sedimentary basins around the world. These iron minerals were mainly derived from flocculent precipitates formed when rivers flow into the ocean, especially in deltaic environments with high hydrodynamic conditions. At the same time, sandstone sequences with grain-coating chlorites also tend to have relatively high glauconite and pyrite content. EPMA composition analysis shows that glauconites with “high Al and low Fe” content indicate slightly to semi-saline marine environments with weak alkaline and weakly reducing conditions. By analyzing the chlorite-containing sandstone bodies of the southern Sichuan Xujiahe Formation, this study found that chlorite was mainly distributed in sedimentary microfacies, including underwater distributary channels, distributary channels, shallow lake sandstone dams, and mouth bars. Chlorite had a tendency to form in the upper parts of sandstone bodies with signs of increased base level, representing the influence of marine (lacustrine transgression. This is believed to be influenced by megamonsoons in the Middle and Upper Yangtze Region during the Late Triassic Epoch. During periods of abundant precipitation, river discharges increased and more Fe particulates flowed into the ocean (lake. In the meantime, increases or decreases in lake level were only affected by precipitation for short periods of time. The sedimentary environment shifted from weakly oxidizing to weak alkaline, weakly reducing conditions as sea level increased, and Fe-rich minerals as authigenic chlorite and glauconite began to form and deposit.

  13. Multivariate analysis of Morphological characters of Pipistrellus Pipistrellus (Schreber, 1774) and P. Nathusii (Keyserling & Blasius, 1839) (Mammalia: Chiroptera) from the Netherlands

    NARCIS (Netherlands)

    Grol, B.P.F.E.

    1985-01-01

    Within the Vespertilionidae the genus Pipistrellus Kaup, 1829 is characterized by the presence of a calcar lobe (epiblema) attached to the calcar bone, the presence of two upper premolars on each side and a forearm length smaller than 38 mm. Two representatives of this genus occur in The

  14. Palynoflóra a vápnité nanofosilie turonu a coniaku v sedimentech spodní podskupiny gosauské křídy, Severní Vápencové Alpy, Rakousko

    Czech Academy of Sciences Publication Activity Database

    Svobodová, Marcela; Švábenická, L.; Lobitzer, H.

    2012-01-01

    Roč. 2011, podzim (2012), s. 232-238 ISSN 0514-8057 Institutional research plan: CEZ:AV0Z30130516 Keywords : Northern Calcareous Alps * Lower Gosau Subgroup * Turonian * Coniacan * palynoflora * calcareous nannofossils * biostratigraphy * paleoenvironment Subject RIV: DB - Geology ; Mineralogy http://www.geology.cz/zpravy/obsah/2011/zpravy_2011-52.pdf

  15. Integrated stratigraphy and paleoenvironmental reconstruction for the Late Cretaceous Danish chalk based on the Stevns-2 core

    DEFF Research Database (Denmark)

    Boussaha, Myriam; Thibault, Nicolas Rudolph; Stemmerik, Lars

    An integrated stratigraphy of the Stevns-2 core located in eastern Denmark is hereby presented based on calcareous nannofossil biostratigraphy and carbon isotope stratigraphy. Carbon and oxygen isotope have been performed on 419 bulk samples. Calcareous nannofossil biostratigraphy has been applied...

  16. An account of the bio- and magnetostratigraphy of the Upper Tithonian—Lower Berriasian interval at Le Chouet, Drôme (SE France)

    Czech Academy of Sciences Publication Activity Database

    Wimbledon, W. A. P.; Reháková, D.; Pszczółkowski, A.; Casellato, K.; Halásová, E.; Frau, C.; Bulot, L. G.; Grabowski, J.; Sobien, K.; Pruner, Petr; Schnabl, Petr; Čížková, Kristýna

    2013-01-01

    Roč. 64, č. 6 (2013), s. 437-460 ISSN 1335-0552 Institutional research plan: CEZ:AV0Z30130516 Institutional support: RVO:67985831 Keywords : Tithonian * Berriasian * integrated biostratigraphy * magnetostratigraphy * microfacies * ammonites * calcareous nannofossils * calcareous dinoflagellates * calpionellids Subject RIV: DE - Earth Magnetism, Geodesy, Geography Impact factor: 0.835, year: 2013

  17. Nördliche Kalkalpen der Umgebung Salzburgs (Exkursion H am 17. April 2009)

    Czech Academy of Sciences Publication Activity Database

    Dorner, R.; Höfling, R.; Lobitzer, H.; Feitzinger, G.; Svobodová, Marcela; Švábenická, L.

    2009-01-01

    Roč. 91, - (2009), s. 317-366 ISSN 0078-2947. [Oberrheinischen geologischen Verein e. v. - Tagung /130./. Salzburg - zentralen Ostalpen, 14.04.2009-18.04.2009] Institutional research plan: CEZ:AV0Z30130516 Keywords : Northern Calcareous Alps * Northern Calcareous Alps ( Austria) * sedimentology Subject RIV: DB - Geology ; Mineralogy

  18. MX Siting Investigation. Geotechnical Evaluation. Verification Study - Lake Valley, Nevada. Volume II. Geotechnical Data.

    Science.gov (United States)

    1981-07-31

    to subrounded, calcarous some sigihtly - * *. * platic clay; stmpgs:cishe 42.W’- 3.51. 2 ::.:. SC doe 1SANDY CLAY, brnon moist slihtly 1 425727...8217:: ;:. -,-.::::"_ __ _ __ _ __ _ _ __ _ __ tegw ////77/* SANDY CLAY. light brown, "moi st slightly platic , calcareous; some fine 8 / / to medium subengular to wubrounded sand. 0

  19. Lime finishing compounds using modified diatomite

    OpenAIRE

    Логаніна, Валентина Іванівна; Камбург, Володимир Григорович; Давидова, Ольга Олександрівна; Симонов, Євген Євгенович

    2012-01-01

    It provides information on the impact of modification of diatomite sol silicon-ing acid on the rheological properties of calcareous composition with the introduction of plasticizers. It is shown that modification of diatomite promotes the improvement exists a plasticizing properties of calcareous composition

  20. Mineral surface processes responsible for the decreased retardation (or enhanced mobilization) of 137Cs from HLW tank discharges. 1998 annual progress report

    International Nuclear Information System (INIS)

    Bertsch, P.M.; Zachara, J.M.

    1998-01-01

    'Cesium (137) is a major component of high level weapons waste. At Hanford, single shell tanks (SST''s) with high level wastes (HLW) have leaked supernate containing over 10 6 Ci of 137 Cs and other co-contaminants into the vadose zone. In select locations, 137 Cs has migrated further than expected from retardation experiments and performance assessment calculations. Deep 137 Cs migration has been observed beneath the SX tank farm at Hanford with REDOX wastes as the carrier causing regulatory and stakeholder concern. The causes for expedited migration are unclear. This research is investigating how the sorption chemistry of Cs on Hanford vadose zone sediments changes after contact with solutions characteristic of HLW. The central scientific hypothesis is that the high Na concentration of HLW will suppress surface-exchange reactions of Cs, except those to highly-selective frayed edge sites (FES) of the micaceous fraction. The authors further speculate that the concentrations, ion selectivity, and structural aspects of the FES will change after contact with HLW and that these changes will be manifest in the macroscopic sorption behavior of Cs. The authors believe that migration predictions of Cs can be improved substantially if such changes are understood and quantified. The research has three objectives: (1.) identify how the multi-component surface exchange behavior of Cs on Hanford sediments changes after contact with HLW simulants that span a range of relevant chemical (Na, OH, Al, K) and temperature conditions (23-80 C); (2) reconcile changes in sorption chemistry with microscopic and molecular changes in site distribution, chemistry, mineralogy, and surface structure of the micaceous fraction; (3) integrate mass-action-solution exchange measurements with changes in the structure/site distribution of the micaceous fraction to yield a multicomponent exchange model relevant to high ionic strength and hydroxide for prediction of environmental Cs sorption.'

  1. Fission track geochronology of Eastern Ghats

    Energy Technology Data Exchange (ETDEWEB)

    Virk, H S; Koul, S L; Singh, S [Punjabi Univ., Patiala (India). Dept. of Physics

    1978-12-01

    Fission track geochronology of Eastern Ghats has been established by using fission track technique in dating micaceous and accessory minerals occurring in the region. Annealing studies confirm that radiation damage fossil tracks can be erased in minerals under intense metamorphic episodes thus resetting the geological clock. The fission track ages of the minerals range between 450 +- 5 m.y. to 622 +- 148 m.y. It is concluded that f.t. ages of the minerals date the last metamorphic event of the Eastern Ghats, known as the Indian Ocean Cycle.

  2. Radiocesium retention in the aquatic, terrestrial and urban environment: a quantitative and unifying analysis

    International Nuclear Information System (INIS)

    Preter, P. de

    1990-01-01

    The frayed edges of 10 A phyllosilicates (micaceous minerals), responsible for the highly selective sorption of poorly hydrated alkali cations (Cs, Rb, K) in NH$/sb4$, are quantitatively characterized by masking the planar sites with silver-thiourea. Both the capacity of the frayed edge sites (FES) and the Cs-to-K selectivity coefficient of these sites can be measured. The loading dependence of the Cs-to-K selectivity coefficient in the FES of 4 micaceous minerals demonstrates a pronounced degree of heterogeneity. Only a small fraction of the FES ($<$10%) exhibits extremely high Cs preference. For studying complex mineralogical systems (soils, sediments, rocks and ceramics) a new parameter is introduced: the ''radiocesium interception potential'', defined as the product of FES capacity and the Cs-to-K (or NH$/sb4$) selectivity coefficient in the FES at ''zero'' Cs loading. This parameter is a powerful tool in describing and predicting the highly selective sorption processes in the FES. Under freshwater conditions the radiocesium distribution coefficient can be quantitatively predicted by considering a competition with K and NH$/sb4$ in the FES. In a marine environment Na, and to a lesser extent Ca and Mg, also have to be taken into account. Finally, evidences for a redistribution process are given: sorbed Cs ions diffuse to the interlayers of the clay particles. This phenomenon explains the increasing ''fixation'' of radiocesium with time

  3. Geochemical and mineralogical controls on mine tailings rehabilitation and vegetation, Otago Schist, New Zealand

    International Nuclear Information System (INIS)

    Craw, D.; Rufaut, C.

    2017-01-01

    Large areas (square kilometre scale) of mine tailings have been deposited from placer gold mines in Central Otago, and are being deposited at Macraes orogenic gold mine in east Otago. Establishment of vegetation on these tailings involves at least some provision of plant nutrients from the rock. Phosphorus is the principal limiting nutrient, as the c. 1000 mg/kg P in accessory apatite, most abundant in micaceous schist, is only sparingly bioavailable on timescales of weeks to months. Nitrogen is an important limiting nutrient but schist, especially micaceous schist, typically contains 500-1000 mg/kg N, and this nitrogen is readily leachable with water on timescales of weeks to months. Arsenic uptake from tailings by pasture species is significant (< 90 mg/kg dry weight), but elevated As in tailings substrates (c. 1500 mg/kg) does not adversely affect plant health. Capping of tailings with variably oxidised schist is the most effective way of facilitating revegetation, and some addition of phosphatic fertiliser is desirable but other nutrients, including nitrogen, are adequately bioavailable in a schist cap and underlying tailings. (author).

  4. Moessbauer spectroscopic study of corrosion products beneath primer coating containing anticorrosive pigments

    International Nuclear Information System (INIS)

    Kumar, A.V.R.; Nigam, R.K.

    1998-01-01

    The phase analysis of the rusts generated beneath the primer containing micaceous iron oxide (MIO) and micaceous iron oxide in combination with red lead (RL), zinc phosphate (ZP), basic lead silicochromate (BLSC) and zinc chromate (ZC) has been carried out by Moessbauer spectroscopy at room temperature. The rust beneath the coating obtained after immersion of the painted panel for six months in 3% NaCl, consists mainly of non-stoichiometric magnetite together with small fractions of γ-, α-FeOOH except in the case of panel painted with RL containing MIO showed only a central doublet indicating the formation of γ-FeOOH and SPM α-FeOOH. Non-stoichiometry of magnetite as calculated from the ratio of B/A sites of the peaks of magnetite in the spectrum has been found depending on the nature of anticorrosive pigment present in the primer coating. The order of non-stoichiometry has been found to be in order of ZC > BLSC > ZP > MIO. (author)

  5. Radiocesium cycling in vegetation and soil

    International Nuclear Information System (INIS)

    Dahlman, R.C.; Francis, C.W.; Tamura, T.

    1975-01-01

    Data on cesium dynamics in vegetation and soils are reviewed. Special emphasis is placed on typical environments in the southeastern United States. Clay minerals of soil, especially micaceous types, effectively fix cesium and remove it from biotic components of ecosystems. Fallout 137 Cs enters food chains principally by direct deposition on vegetation; uptake by the root pathway is usually less than direct contamination of plant foliage. Cesium-137 levels in vegetation of the southeastern U. S. Coastal Plain are estimated on the basis of direct deposition from the atmosphere and root uptake from soil. Estimated concentrations, based on current concepts of 137 Cs dynamics in vegetation and fixation in soil, are in good agreement with observed values of 137 Cs in vegetation collected in 1969 and 1970. Mechanisms of direct deposition and of increased uptake by roots due to the absence of micaceous clays adequately explain the higher levels of 137 Cs in vegetation of the Coastal Plain and thus are responsible for the elevated 137 Cs reported for milk of the Tampa, Fla., milkshed

  6. Rb-Sr and K-Ar age of globular phyllosilicates and biostratigraphy of the Riphean deposits of the Olenek Uplift (North Siberia)

    Science.gov (United States)

    Zaitseva, T. S.; Gorokhov, I. M.; Semikhatov, M. A.; Ivanovskaya, T. A.; Kuznetsov, A. B.; Dorzhieva, O. V.

    2017-11-01

    This work presents results of the complex mineralogical, geochemical, and isotope-geochronological investigation of globular dioctahedral 2: 1 phyllosilicates (GPS) of the illite-glauconite series from the Riphean sequences of the Olenek Uplift. It is established that GPS (glauconite, Al-glauconite, Fe-illite) in deposits of the Arymass, Debengda, and Khaipakh formations are represented by mixed-layer varieties of two types: (1) with relatively low (cell of minerals varies from 9.18 to 9.72 Å. The Rb-Sr age dating of GPS was first carried out in combination with the calculation of theoretical pattern of the cation distribution in the mineral structure and comparison of the calculation results obtained with the Mössbauer and IR spectroscopy data. This approach is based on the assumption that development and evolution of isotope systems in GPS are synchronous with the evolution of the crystalline structure of the mineral at various stages of the geological and geochemical history of the development of sedimentary units. Analysis of the obtained data allows us to state that the structural features of the Riphean GPS from the Olenek section reflect the early diagenetic stages of the formation of the minerals studied. The 87Sr/86Sr initial ratios in the studied sediments are consistent with the range of variations in this ratio in the Middle Riphean Ocean (0.7049-0.7061). The Rb-Sr and K-Ar ages of the GPS of the Arymass (1305 ± 8 and 1302 Ma, respectively), Debengda (1265 ± 12 and 1284 ± 22 Ma), and Khaipakh (1172 ± 18 and 1112 ± 24 Ma) formations in the Olenek Uplift section are close to the accumulation time of corresponding deposits and, correspondingly, have significance for stratigraphic correlations.

  7. Diagenetic alteration process of chlorite in Tyr Member sandstone, Siri Canyon, Danish North Sea

    DEFF Research Database (Denmark)

    Kazerouni, Afsoon Moatari; Friis, Henrik; Hansen, Jens Peter Vind

    only in traceable amounts in the samples which are dominated by microquartz cement. There seem to be two chlorite phases: The first phase occurs as rosettes in a grain coating growth pattern. It is partially intergrown with microquartz or forms a dense mixture of small chlorite rosettes and scattered...... microquartz. Pore-lining chlorite is partially post-compactional and grows into fractures in glauconite grains. Pore lining chlorite is formed prior to macroquartz and post-compactional calcite; whereas early calcite cemented samples did not evolve chlorite. The general impression is, however, that chlorite...

  8. Activation analysis of deposited dust brought to Israel by dust storms

    International Nuclear Information System (INIS)

    Ganor, E.; Tal, A.; Donagi, A.

    1975-01-01

    The determination of dust particles deposited in Jerusalem during regional dust storms was carried out by polarized microscopy, X-ray analysis and atomic absorption measurements. These analyses showed the presence of particles of quartz, calcite, dolomite, feldspar, halite, kaolinite, montmorillonite, epidote, tourmaline, glauconite, illite and other heavy minerals. The aims of the present study were to apply activation analysis for the determination of element composition in dust samples; to compare the results obtained by activation analysis with those obtained by other methods, i.e. chemical analysis, polarized microscopy and X-ray analysis. The results obtained by the various methods were in good agreement. (B.G.)

  9. Image Analysis and Estimation of Porosity and Permeability of Arnager Greensand, Upper Cretaceous, Denmark

    DEFF Research Database (Denmark)

    Solymar, Mikael; Fabricius, Ida

    1999-01-01

    Arnager Greensand consists of unconsolidated, poorly sorted fine-grained, glauconitic quartz sand, often silty or clayey, with a few horizons of cemented coarse-grained sand. Samples from the upper part of the Arnager Greensand were used for this study to estimate permeability from microscopic...... images. Backscattered Scanning Electron Microscope images from polished thin-sections were acquired for image analysis with the software PIPPIN(R). Differences in grey levels owing to density differences allowed us to estimate porosity, clay and particle content. The images were simplified into two...

  10. Tithonian age of dinosaur fossils in central Patagonian, Chile: U-Pb SHRIMP geochronology

    Science.gov (United States)

    Suárez, Manuel; De La Cruz, Rita; Fanning, Mark; Novas, Fernando; Salgado, Leonardo

    2016-11-01

    Three Tithonian concordant U-Pb SHRIMP zircon ages of 148.7 ± 1.4, 147.9 ± 1.5 and 147.0 ± 1.0 from tuffs intercalated in a clastic sedimentary succession with exceptional dinosaur bones including the new taxon Chilesaurus diegosuarezi gen. et sp. nov. exposed in central Chilean Patagonia (ca. 46°30'S) are reported herein. The fossiliferous beds accumulated in a synvolcanic fan delta reaching a shallow marine basin as indicated by glauconite present in some of the beds, and coeval with the beginning of the transgression of the Aysén Basin.

  11. Biochemical studies on some zooplankton off the west coast of India

    Digital Repository Service at National Institute of Oceanography (India)

    Goswami, S.C.; Rao, T.S.S.; Matondkar, S.G.P.

    Proximate biochemical analyses on twelve zooplankton species showed that protein was the predominant biochemical component followed by lipid. Carbohydrate content was very low especially in species with high water content or calcareous shell...

  12. The Rajahmundry Traps, Andhra Pradesh: Evaluation of their ...

    Indian Academy of Sciences (India)

    R. Narasimhan (Krishtel eMaging) 1461 1996 Oct 15 13:05:22

    consisting of unfossiliferous yellow calcareous shale. (Pascoe 1964). For the east .... allowing the evolved gas to be pumped away. Ages are reported relative to ..... extraction work and sources of air argon contamination;. Can. J. Earth Sci.

  13. Effects of elemental sulfur and sulfur-containing waste on nutrient ...

    African Journals Online (AJOL)

    STORAGESEVER

    2009-09-15

    Sep 15, 2009 ... grown twice on the same soils to determine initial and residual effects of applied S. Results showed that applications of ... Key words: Calcareous soil, plant growth, plant nutrition, sulfur application. ...... Colombia. Can. J. Soil ...

  14. Conodont-bearing formations of Devonian and Lower Carboniferous age in northern León and Palencia (Spain)

    NARCIS (Netherlands)

    Adrichem Boogaert, van H.A.

    1965-01-01

    Conodonts have been extracted from calcareous units of the Devonian and Lower Carboniferous sequence from 3 areas in the S. part of the Cantabrian Mountains. There can be distinguished Emsian, Givetian, Frasnian, Famennian and Viséan faunas.

  15. A Late Pleistocene clockwise rotation phase of Zakynthos (Greece) and implications for the evolution of the western Aegean arc

    NARCIS (Netherlands)

    Duermeijer, C.E.; Krijgsman, W.; Langereis, C.G.; Meulenkamp, J.E.; Triantaphyllou, M.V.; Zachariasse, W.J.

    1999-01-01

    Palaeomagnetic measurements have been carried out on Eocene to Pleistocene sediments on the Ionian island of Zakynthos, NW Greece. Magnetostratigraphic constraints, biostratigraphic analyses of planktonic foraminifera and calcareous nannofossils provide a reliable time frame for these deposits.

  16. Integrated stratigraphy and 40Ar/39Ar chronology of early Middle Miocene sediments from DSDP Leg 42A, Site 372 (Western Mediterranean)

    NARCIS (Netherlands)

    Abdul Aziz, H.; di Stefano, A.; Foresi, L. M.; Hilgen, Frederik J.; Iaccarino, S. M.; Kuiper, K. F.; Lirer, F.; Salvatorini, G.; Turco, E.

    2008-01-01

    An integrated magneto-biostratigraphic framework is presented for Middle Miocene sediments of DSDP Site 372 located in the Western Mediterranean. Detailed biostratigraphic analysis shows a nearly complete sequence of early Middle Miocene calcareous plankton bioevents in the Mediterranean, including

  17. Assessing the suitability of benthic foraminiferal morpho-groups to reconstruct paleomonsoon from Bay of Bengal

    Digital Repository Service at National Institute of Oceanography (India)

    Manasa, M.; Saraswat, R.; Nigam, R.

    into rounded symmetrical (RSBF) and angular asymmetrical benthic foraminifera (AABF). Additionally, a few other dominant groups were also identified based on test composition (agglutinated, calcareous) and abundance (Asterorotalids and Nonions). The relative...

  18. Remote sensing and aerial photography for coastal geomorphology

    Digital Repository Service at National Institute of Oceanography (India)

    Wagle, B.G.

    composition as the loose beach sand. It is friable to well cemented rock consisting of mineral grains,; rock fragments and calcareous debris,cemented by calcium carbonate. It is formed only in the intertidal zone or spray zone. Beach Ridges...

  19. The effects of increased phosphorus application on shoot dry matter ...

    African Journals Online (AJOL)

    The effects of increased phosphorus application on shoot dry matter, shoot P and Zn concentrations in wheat ( Triticum durum L.) and maize ( Zea mays L.)wheat ( Triticum durum L.) and maize ( Zea mays L.) grown in a calcareous soil.

  20. Distribution of foraminifera in the lagoons of certain Islands of the Lakshadweep Archipelago, Arabian Sea

    Digital Repository Service at National Institute of Oceanography (India)

    Rao, K.K; Sivadas, P.; Narayanan, B.; Jayalakshmy, K; Kutty, M.K

    , but arenaceous forms are very rare due to coarse nature of the deposits. Of the families observed, Miliolidae, Calcarinidae, and Amphisteginidae are most abundant and 2 species, Calcarina calcar and Amphistegina radiata are the most dominant. Planktonic...

  1. African Journal of Biotechnology - Vol 11, No 21 (2012)

    African Journals Online (AJOL)

    Genetic diversity among four Eucalyptus species (myrtaceae) based on random ... biomass and enzyme activities in some alkaline calcareous subtropical soils .... Growth characteristics and productivity of tall fescue new variety 'Purumi' in ...

  2. Rare earth element patterns of the Central Indian Basin sediments related to their lithology

    Digital Repository Service at National Institute of Oceanography (India)

    Nath, B.N.; Roelandts, I.; Sudhakar, M.; Pluger, W.L.

    Rare earth element (REE) concentration have been determined in terrigenous, siliceous (nodule barren and nodule bearing), calcareous, and red clay from the Central Indian Basin. The bulk distribution of REE, and in particular the relative cerium...

  3. Lišejníky NPP Kaňk u Kutné Hory

    Czech Academy of Sciences Publication Activity Database

    Malíček, Jiří

    2017-01-01

    Roč. 59, č. 1 (2017), s. 30-36 ISSN 0862-8904 Institutional support: RVO:67985939 Keywords : Acarospora rehmii * biodiversity * calcareous conglomerates Subject RIV: EF - Botanics OBOR OECD: Plant sciences, botany

  4. Barotolerance of fungi isolated from deep-sea sediments of the Indian Ocean

    Digital Repository Service at National Institute of Oceanography (India)

    Raghukumar, C.; Raghukumar, S.

    Two species of filamentous fungi, Aspergillus ustus (Bain.) Thoms and Church and Graphium sp., were isolated from calcareous animal shells at depths of 860 m in the Arabian Sea and 965 m in the Bay of Bengal. Laboratory experiments showed...

  5. Atlantic Oceanography. Volume 1

    Science.gov (United States)

    1978-08-01

    on the effect of environmental characteristics upon the encrusting calcareous-tube-making polychaete worm Hydroides dianthus has been begun, and it is...B. eb!Lineus. In spring 1978, work uas initiated on rearing the larvae of the calcareous encrusting tube worm Hydroides dianthus . Preliminary...larvae belonging to the coastal species, Balanus amphitrite and Hydroides dianthus and the estuarine barnacle, BaZanus ebur-neus. Some of the difficulties

  6. [Functional rehabilitation of degenerative tendinous injuries of the shoulder].

    Science.gov (United States)

    Greve, J M; Rossi, J D; Cossermelli, W; Ferreira Filho, A A

    1991-01-01

    We studied 60 shoulders in a group of 58 patients, with injuries of shoulder tendons. Thirty-one patients presented impingement syndrome, eighteen patients calcareous tendinitis, five patients rotator cuff rupture, three patients bicipital tendinitis and three patients multiple lesions. All of them were submitted to physical therapy: ultra-sound and kinesio-therapy. Good results were obtained in 55% of the patients. Bad results were recorded in women, young people and in patients with calcareous tendinitis.

  7. The latest Paleocene benthic extinction event: Punctuated turnover in outer neritic benthic foraminiferal faunas from Gebel Aweina, Egypt

    OpenAIRE

    Speijer, Robert; Schmitz, B; Aubry, MP; Charisi, SD

    1995-01-01

    We investigated the benthic foraminiferal record of the neritic sequence at Gebel Aweina (Nile Valley, Egypt) in relation to the latest Paleocene deep-sea benthic extinction event (BEE). At Gebel Aweina an expanded sequence, spanning calcareous nannofossil Zones NP8-NPlO, is continuously exposed and yields calcareous microfauna throughout. The BEE level is situated about halfway through Zone NP9 at 17m above the base of the Esna Formation. Detailed biostratigraphic and isotopic studies have i...

  8. Evaluation of ammonium nitrate phosphate (Suphala) having different water soluble phosphorus levels on black soils

    International Nuclear Information System (INIS)

    Deo Dutt; Mutatkar, V.K.; Chapke, V.G.

    1974-01-01

    Efficiency of the laboratory prepared 32 P tagged ammonium nitrate phosphate (Suphala) varying in water soluble P was studied both on calcareous and non-calcareous soils of Maharashtra for bajra and wheat crops under greenhouse conditions. The results revealed a significant increase in dry matter production and uptake of total and fertilizer P with Suphala containing 30-32% water-soluble phosphorus. (author)

  9. Seismic Response to Sonic Boom-Coupled Rayleigh Waves

    Science.gov (United States)

    1990-06-28

    side slopes and moderately deep well-drained, gently sloping to moderately steep soils on terraces; Ann. Rainfall--10" to 16") Cath-Timpahute- Jarab ...slopes less than 15%, and Alluvial land) Jarab Series (cobbley loam, gravelly loam, gravelly clay loam, pan fragments, hardpan with silica laminae...weakly and strongly cemented with lime, soft, calcareous gravelly loam: al!-aline, calcareous) Jarab cobbley loam, 2 to 15% slopes, (JCD) (moderately

  10. Water quality in the coastal area of Santa Marta (Colombia)

    International Nuclear Information System (INIS)

    Garcia Francisco; Palacio Carlos; Garcia Uriel

    2012-01-01

    Multivariate statistical techniques were used to investigate the temporal and spatial variations of water quality at the Santa Marta coastal area where a submarine out fall that discharges 1 m3/s of domestic wastewater is located. Two-way analysis of variance (ANOVA), cluster and principal component analysis and Krigging interpolation were considered for this report. Temporal variation showed two heterogeneous periods. From December to April, and July, where the concentration of the water quality parameters is higher; the rest of the year (May, June, August-November) were significantly lower. The spatial variation reported two areas where the water quality is different, this difference is related to the proximity to the submarine out fall discharge. Calcareous sands are unique in terms of their origin, mineralogy, shape, fragility and intra particle porosity. This article presents results from an experimental program carried out to study the liquefaction resistance of a calcareous sand retrieved from Cabo Rojo at Puerto Rico. The experimental program included mineralogical characterization, index properties, and undrained cyclic triaxial tests on isotropically consolidated reconstituted samples. Due to the large variation in the calcareous sand properties, results are compared with previous researches carried out on other calcareous sands around the world. Results showed a wide range in the liquefaction resistance of the studied calcareous sands. Cabo Rojo sand experienced greater liquefaction resistance than most of the calcareous sands used for comparison. Important differences in the excess pore pressure generation characteristics were also found.

  11. Radiocesium sorption in relation to clay mineralogy of paddy soils in Fukushima, Japan

    Energy Technology Data Exchange (ETDEWEB)

    Nakao, Atsushi, E-mail: na_4_ka_triplochiton@kpu.ac.jp [Graduate School of Life and Environmental Sciences, Kyoto Prefectural University, Hangi-cho 1-5, Shimogamo, Sakyo-ku, Kyoto 606-8522 (Japan); Ogasawara, Sho [Graduate School of Life and Environmental Sciences, Kyoto Prefectural University, Hangi-cho 1-5, Shimogamo, Sakyo-ku, Kyoto 606-8522 (Japan); Sano, Oki; Ito, Toyoaki [Field Science Center, Graduate School of Agricultural Science, Tohoku University, Naruko-Onsen 232-3, Osaki, Miyagi 989-6711 (Japan); Yanai, Junta [Graduate School of Life and Environmental Sciences, Kyoto Prefectural University, Hangi-cho 1-5, Shimogamo, Sakyo-ku, Kyoto 606-8522 (Japan)

    2014-01-01

    Relationships between Radiocesium Interception Potential (RIP) and mineralogical characteristics of the clay fraction isolated from 97 paddy soils (Hama-dori, n = 25; Naka-dori, n = 36; Aizu, n = 36) in Fukushima Prefecture, Japan were investigated to clarify the mineralogical factors controlling the {sup 137}Cs retention ability of soils (half-life 30.1 y). Of all the fission products released by the Fukushima accident, {sup 137}Cs is the most important long-term contributor to the environmental contamination. The RIP, a quantitative index of the {sup 137}Cs retention ability, was determined for the soil clays. The composition of clay minerals in the soil clays was estimated from peak areas obtained using X-ray diffraction (XRD) analyses. The predominant clay mineral was smectite in soils from Hama-dori and Aizu, while this was variable for those from Naka-dori. Native K content of the soil clays was found to be an indicator of the amount of micaceous minerals. The average RIP for the 97 soil clays was 7.8 mol kg{sup −1}, and ranged from 2.4 mol kg{sup −1} to 19.4 mol kg{sup −1}. The RIP was significantly and positively correlated with native K content for each of the geographical regions, Hama-dori (r = 0.76, p < 0.001), Naka-dori (r = 0.43, p < 0.05), and Aizu (r = 0.76, P < 0.001), while it was not related to the relative abundance of smectite. The linear relationship between RIP and native K content not only indicate a large contribution of micaceous minerals to the {sup 137}Cs retention ability of the soil clays, but also could be used to predict the {sup 137}Cs retention ability of soil clays for other paddy fields in Fukushima and other areas. - Highlights: • RIP was measured for 97 paddy soils from Fukushima to assess {sup 137}Cs retention ability. • The dominant clay mineral was smectite, but this did not control RIP. • RIP was positively correlated with native K content. • Micaceous minerals were found to control the {sup 137}Cs retention

  12. SOLUBILIZATION OF POTASSIUM FROM ALTERNATIVE ROCKS BY HUMIC AND CITRIC ACIDS AND COFFEE HUSK

    Directory of Open Access Journals (Sweden)

    Rodrigo Souza Pessoa

    2015-12-01

    Full Text Available ABSTRACT Brazil imports most of the potassium that it consumes in agriculture, however, such huge external dependence can be minimized with the use of alternative local K bearing rocks. This experiment was conducted with the objective of evaluating the solubility of nepheline syenite and glauconite as a function of three organic matrices, humic acid, citric acid and coffee husk. Incubation of low grade K rocks and organic matrices were done in laboratory conditions, in a completely randomized design. Each rock was mixed with five different doses of each organic matrix and the potassium solubilized was measured periodically, during 180 days. Regardless of the organic matrix and its dose investigated, nepheline syenite samples released more K than the modified glauconite. Soluble K increased as the incubation time increased and its release was greater as the organic matrix dose increased. There was more soluble K when the coffee husk was mixed with the potassic rocks, in relation to the humic and citric acids.

  13. Amelioration of soils damaged by uranium mining

    International Nuclear Information System (INIS)

    Rajchev, T.; Gribachev, P.; Atanasov, I.; Petkova, D.; Popandova, S.

    1998-01-01

    Three liming materials have been investigated: ground limestone (CaCO 3 ), ground glauconite-phosphorite and carbonite-hydroxide sediment as materials to be used for correction of acid-soil conditions, developed as a result of sulfuric acid solution spills on soils of uranium producing sites located in Momino village (South Bulgaria). A pot experiment has been carried out with test-culture alfalfa using three dosage of examined lime materials: 1. amounts of lime material calculated to neutralize approximately 95% of exchangeable H + and Al - ; 2. amounts of lime material calculated for full neutralizing of exchangeable acidity and 3. amounts of lime materials calculated on the basis of over-liming in order to increase the pH values of the soils up to 7.6-7.8. The experiment shows that best results are obtained with amounts of lime materials calculated on the basis of over-liming and addition of humic substances to the lime materials. Among the three lime substances the most effective was glauconite-phosphorite and carbonate-hydroxide sediments

  14. Natural sorbents as barriers against migration of radionuclides from radioactive waste repositories

    International Nuclear Information System (INIS)

    Stefanova, I.; Gradev, G.D.

    1993-01-01

    The sorption properties of Bulgarian inorganic sorbents - clinoptilolite, vermiculite, bentonite, glauconite, celadonite and loess, which can be used as buffer, backfill and sealing materials in radwaste repository are studied. Experimental data about sorption and desorption capacities, radiation and thermal stability of sorbents from different Bulgarian deposits are reported and compared. Clinoptilolite from Beli Plast and its sodium variety from Kostino and Moryantsi is recommended as a barrier against radionuclide migration from radwaste repository due to their high sorption capacity of 137 Ce, 90 Sr and 60 Co. The high selectivity of vermiculite for polyvalent ions ( 144 Ce, 59 Fe and 90 Sr) gives grounds to include the sorption on vermiculite as a second step in the ion exchange technology for low level laundry waste decontamination. Bentonite is studied as a proposed buffer, backfill and sealing material. Its selectivity for cesium is lower compared to those of clinoptilolite. Thus a tailored-made mixture of bentonite and clinoptilolite will act as a barrier against radionuclides in different oxidation state. Glauconite can be successfully used as a barrier against migration of 144 Ce, 90 Sr, 54 Mn and 65 Zn. Loess is also included in the study, as the Kozloduy NPP is sited on loess formation and it is a natural potential site for low and intermediate level waste burial. It is concludes that zeolites and clays of Bulgarian deposits can be used effectively against radionuclide migration from radioactive waste repositories. 59 refs., 5 tabs. (author)

  15. Moessbauer spectroscopy and X-ray diffraction analyses of clayey samples used as ceramic sourcing materials, in Peru

    Energy Technology Data Exchange (ETDEWEB)

    Quille, Ruben, E-mail: quilleruben@gmail.com; Bustamante, Angel [San Marcos National University, Laboratory of Ceramics and Nanomaterials, Faculty of Physical Sciences (Peru); Palomino, Ybar [National University of San Cristobal de Huamanga, Experimental Center of Ceramics (Peru)

    2011-11-15

    The ceramic industry is an important area of economic activity in the Ayacucho Region, in particular in the District of Quinua. As a consequence, there is a huge demand for clay to produce ceramic pastes in that region. This paper reports on results concerning the mineralogical characterization of four clayey samples, which were collected MAA and SPQA from the area Pampa de La Quinua with geographic coordinates 13 Degree-Sign 02 Prime 49 Double-Prime S 74 Degree-Sign 08 Prime 03 Double-Prime W, CE1M and CE2M from the Quinua locality 13 Degree-Sign 03 Prime 07 Double-Prime S 74 Degree-Sign 08 Prime 31 Double-Prime W, both in the District of Quinua, Province of Huamanga, Ayacucho, Peru. The chemical and mineralogical characterization of these samples was carried out with powder X-ray diffraction detecting quartz, albite, montmorillonite, kaolinite and glauconite mineral phases, Moessbauer spectroscopy detected iron in kaolinite, glauconite and montmorillonite minerals. Chemical analysis was performed through scanning electron microscopy and energy dispersive X-ray spectroscopy. Data obtained from the combination of these techniques provided relevant information about the morphology, chemical composition, and the mineralogy of samples.

  16. Mössbauer spectroscopy and X-ray diffraction analyses of clayey samples used as ceramic sourcing materials, in Peru

    Science.gov (United States)

    Quille, Rubén; Bustamante, Ángel; Palomino, Ybar

    2011-11-01

    The ceramic industry is an important area of economic activity in the Ayacucho Region, in particular in the District of Quinua. As a consequence, there is a huge demand for clay to produce ceramic pastes in that region. This paper reports on results concerning the mineralogical characterization of four clayey samples, which were collected MAA and SPQA from the area Pampa de La Quinua with geographic coordinates 13° 02' 49″ S 74° 08' 03″ W, CE1M and CE2M from the Quinua locality 13° 03' 07″ S 74° 08' 31″ W, both in the District of Quinua, Province of Huamanga, Ayacucho, Peru. The chemical and mineralogical characterization of these samples was carried out with powder X-ray diffraction detecting quartz, albite, montmorillonite, kaolinite and glauconite mineral phases, Mössbauer spectroscopy detected iron in kaolinite, glauconite and montmorillonite minerals. Chemical analysis was performed through scanning electron microscopy and energy dispersive X-ray spectroscopy. Data obtained from the combination of these techniques provided relevant information about the morphology, chemical composition, and the mineralogy of samples.

  17. Mössbauer spectroscopy and X-ray diffraction analyses of clayey samples used as ceramic sourcing materials, in Peru

    International Nuclear Information System (INIS)

    Quille, Rubén; Bustamante, Ángel; Palomino, Ybar

    2011-01-01

    The ceramic industry is an important area of economic activity in the Ayacucho Region, in particular in the District of Quinua. As a consequence, there is a huge demand for clay to produce ceramic pastes in that region. This paper reports on results concerning the mineralogical characterization of four clayey samples, which were collected MAA and SPQA from the area Pampa de La Quinua with geographic coordinates 13° 02′ 49″ S 74° 08′ 03″ W, CE1M and CE2M from the Quinua locality 13° 03′ 07″ S 74° 08′ 31″ W, both in the District of Quinua, Province of Huamanga, Ayacucho, Peru. The chemical and mineralogical characterization of these samples was carried out with powder X-ray diffraction detecting quartz, albite, montmorillonite, kaolinite and glauconite mineral phases, Mössbauer spectroscopy detected iron in kaolinite, glauconite and montmorillonite minerals. Chemical analysis was performed through scanning electron microscopy and energy dispersive X-ray spectroscopy. Data obtained from the combination of these techniques provided relevant information about the morphology, chemical composition, and the mineralogy of samples.

  18. Magnetic properties of sheet silicates

    International Nuclear Information System (INIS)

    Ballet, O.; Coey, J.M.D.

    1982-01-01

    Susceptibility, magnetisation and Moessbauer measurements are reported for a representative selection of 2:1 layer phyllosilicates. Eight samples from the mica, vermiculite and smectite groups include examples diluted in iron which are paramagnetic at all temperatures, as well as iron-rich silicates which order magnetically below 10 K. Anisotropic susceptibility of crystals of muscovite, biotite and vermiculite is quantitatively explained with a model where the Fe 2+ ions lie in sites of effective trigonal symmetry, the trigonal axis lying normal to the sheets. The ferrous ground state is an orbital singlet. Ferric iron gives an isotropic contribution to the susceptibility. Fe 2+ -Fe 2+ exchange interactions are ferromagnetic with Gapprox. equal to2 K, whereas Fe 3+ -Fe 3+ coupling is antiferromagnetic in the purely ferric minerals. A positive paramagnetic Curie temperature for glauconite may be attributable to Fe 2+ → Fe 3+ charge transfer. Magnetic order was found to set in inhomogeneously for glauconite at 1-7 K. One biotite sample showed an antiferromagnetic transition at Tsub(N) = 7 K marked by a well-defined susceptibility maximum. Its magnetic structure, consisting of ferromagnetic sheets with moments in their planes coupled antiferromagnetically by other, weak interactions, resembles that found earlier for the 1:1 mineral greenalite. (orig.)

  19. CHARACTERIZATION AND PROCESSING OF SCALES FROM THE MECHANICAL DESCALING OF CARBON STEELS FOR RECYCLING AS COATING PIGMENTS

    Directory of Open Access Journals (Sweden)

    Anderson de Oliveira Fraga

    2014-10-01

    Full Text Available The large volume of solid wastes generated as scales in Steel Mills accounts to circa 1% to 2% of the total steel production and has led to studies aiming the recycling of scales, usually resulting in products of low added value. In this study, scales from the mechanical descaling of SAE 1045 steel were characterized by SEM and by quantitative X-Ray diffraction (Rietveld method, as well as by differential thermal analysis, aiming to develop its pretreatment for the further use as lamellar pigments in anticorrosive coatings of high added value. Aspect ratios between 1:50 and 1:100 were obtained by the processing of scales, which allows the replacement of other micaceous iron oxides.

  20. LA CERÁMICA COMÚN DE MESA, COCINA Y DESPENSA EN EL ALTO DUERO DURANTE EL PERIODO BAJOIMPERIAL: UN ENSAYO DE CLASIFICACIÓN

    Directory of Open Access Journals (Sweden)

    Jesús Bermejo Tirado

    2011-10-01

    Full Text Available En este artículo hemos tratado de realizar una primera sistematización del estudio de la cerámicac omún y de despensa en la región del Alto Duero durante el Bajo Imperio (grosso modo mediados del siglo III d. C.– primeras décadas del V d. C.. Para ello establecemos una propuesta tipológica a partir de una serie de contextos cerámicos conocidos. Las categorías de clasificación obtenidas se basan en una metodología que incluye tres niveles interconectados de análisis: tecnología, funcionalidad y morfología.

  1. Preservation and concentration of uranium mineralization in the crust of weathering

    International Nuclear Information System (INIS)

    Ashikhmin, A.A.; Kuznetsov, S.V.; Shmarovich, E.M.

    1983-01-01

    Inprecision of the concept on indispensable evacuation of U from ores during formation of the crust of weathering of lateritic or kaolinitic profile due to the existence of oxidative situation in the crusts is established. At hydrothermal uranium deposit in Eocambrian sandy-shaly and Paleozoic volcanogenous-sedimentary rocks a high degree of mineralization preservation in lower and medium horizons of Mesozoic-Cenozoic hydro-micaceous-kaolinitic crust of weathering, characterized by reductive situation, presence of carbonaceous substance, pyrite and siderite, is established. Mineralization attained there black composition and was additionally enriched with uranium. A supposition is made that the case is specific for the development of lateritic and kaolinitic crust formation according to ore-bearing rocks, rich in reducing agents-carbonaceous substances, sulfides and minerals of protoxidic iron. The data obtained should be taken into account during prediction and prospecting activities

  2. New technology for recyclingmaterials from oily cold rollingmill sludge

    Science.gov (United States)

    Liu, Bo; Zhang, Shen-gen; Tian, Jian-jun; Pan, De-an; Meng, Ling; Liu, Yang

    2013-12-01

    Oily cold rolling mill (CRM) sludge is one of metallurgical industry solid wastes. The recycle of these wastes can not only protect the environment but also permit their reutilization. In this research, a new process of "hydrometallurgical treatment + hydrothermal synthesis" was investigated for the combined recovery of iron and organic materials from oily CRM sludge. Hydrometallurgical treatment, mainly including acid leaching, centrifugal separation, neutralization reaction, oxidizing, and preparation of hydrothermal reaction precursor, was first utilized for processing the sludge. Then, micaceous iron oxide (MIO) pigment powders were prepared through hydrothermal reaction of the obtained precursor in alkaline media. The separated organic materials can be used for fuel or chemical feedstock. The quality of the prepared MIO pigments is in accordance with the standards of MIO pigments for paints (ISO 10601-2007). This clean, effective, and economical technology offers a new way to recycle oily CRM sludge.

  3. The specific interception potential of soils for radiocesium

    International Nuclear Information System (INIS)

    Sweeck, L.; Wauters, J.; Valcke, E.; Cremers, A.

    1990-01-01

    A simple methodology is presented for obtaining the specific interception potential for radiocesium, defined as the product of the number of specific sites times the Cs to K selectivity coefficient in these sites. This procedure is applied to a series of soils from a heavy clay to a podzol soil and it is shown that this interception potential may vary by some two orders of magnitude. On the basis of selectivity values of K and NH 4 -ions for the specific sites, it is demonstrated quantitatively that the specific sites are directly associated with the presence of micaceous clay minerals. In conclusion, a set of equations is developed for predicting the site K D - values of radiocesium on the basis of the specific radiocesium interception potential and the K and NH 4 -concentrations in the soil solution. (author)

  4. New technology for recycling materials from oily cold rolling mill sludge

    Institute of Scientific and Technical Information of China (English)

    Bo Liu; Shen-gen Zhang; Jian-jun Tian; De-an Pan; Ling Meng; Yang Liu

    2013-01-01

    Oily cold rolling mill (CRM) sludge is one of metallurgical industry solid wastes. The recycle of these wastes can not only protect the environment but also permit their reutilization. In this research, a new process of“hydrometallurgical treatment+hydrothermal synthesis”was investigated for the combined recovery of iron and organic materials from oily CRM sludge. Hydrometallurgical treatment, mainly including acid leaching, centrifugal separation, neutralization reaction, oxidizing, and preparation of hydrothermal reaction precursor, was first utilized for processing the sludge. Then, micaceous iron oxide (MIO) pigment powders were prepared through hydrothermal reaction of the obtained precursor in alkaline media. The separated organic materials can be used for fuel or chemical feedstock. The quality of the prepared MIO pigments is in accordance with the standards of MIO pigments for paints (ISO 10601-2007). This clean, eff ective, and economical technology off ers a new way to recycle oily CRM sludge.

  5. Paleomagnetic results from Late Pennsylvanian marls and Early Permian red paleosols of the Dunkard group, Ohio and West Virginia, U.S.A.

    Science.gov (United States)

    Abrajevitch, A.; Oliva, B.; Peters, S.; Beehr, A.; van der Voo, R.

    2006-12-01

    Sediments of the Dunkard Gr. were deposited in the Appalachian foreland basin during the Pennsylvanian and Early Permian, an interval encompassing the long reverse polarity Kiaman chron. Lithofacies in the Dunkard Gr. in eastern Ohio and western West Virginia include lenticular and sheet-form cross-bedded micaceous sandstones, coal, mottled red and purple mudstones, gray laminated mudstones and argillaceous lime mudstones. They are indicative of deposition on a low-gradient, tropical wet-dry fluvial plain. Few lithofacies are laterally persistent over sufficiently long distances, so that correlation schemes are based largely on coal horizons, partly for historical economic reasons and partly because coal beds appear to be more laterally persistent than most other lithofacies. Magnetostratigraphy would therefore provide a powerful additional correlation tool in the Dunkard Gr, A short normal polarity interval has been reported in the Dunkard Gr. (Helsley, 1965), but to date such a change in magnetic field polarity has not been confirmed by later studies. To confirm the presence of the normal polarity subchron and to explore the possibility of using it as a correlation tool in the Dunkard Gr., we sampled 5 sections thought to straddle the Late Pennyslvanian-Early Permian boundary. Sampled lithofacies include red and mottled red-purple paleosols, grey mudstones containing siderite concretions, micaceous sandstones, and dark gray argillaceous limestones. Samples were demagnetized thermally and by AF. The remanent magnetic directions agree with those expected for the Early Permian. A change in polarity was detected in three of the studied sections. Magnetization is carried by several different magnetic minerals, mostly hematite in paleosols and iron sulfides in combination with magnetite in sandstones, marls and limestones. Although we have found good evidence for the normal polarity interval within Kiaman age rocks of the Dunkard Gr., additional magnetostratigraphic

  6. Effects of cathodic protection potential and stress ratio on fatigue thresholds of structured steels in sea water

    Energy Technology Data Exchange (ETDEWEB)

    Dolphin, A.S.; Tice, D.R.

    1987-09-01

    The results reported here suggest that the very high thresholds found under reducing {Delta}K conditions may be inapplicable under the increasing {Delta}K conditions likely to be more relevant to real structures. This conclusion is based on just two tests at - 0.85V SCE, and so requires confirmation over a range of R ratios and at free corrosion and overprotection potentials. Crack growth thresholds appear to be higher under cathodic over-protection conditions (-1.05V SCE) than at more positive potentials, due to calcareous scale formation. Tests at negative R ratios are required to ensure this calcareous scale would remain intact under compressive loading. Due to the large observed influence of calcareous scale on crack growth, and particularly on the arrest of growing cracks, more detailed microstructural examination is recommended on the specimens tested in this programme. (author).

  7. Soils developed from marine and moraine deposits on the Billefjord coast, West Spitsbergen

    Science.gov (United States)

    Pereverzev, V. N.

    2012-11-01

    Morphogenetic features of soils developed from noncalcareous and calcareous deposits of the marine and glacial origins on the coasts of Billefjord and Petunia Bay in West Spitsbergen are studied. Grayhumus (soddy) soils develop from noncalcareous deposits; they consist of the AO-AY-C horizons and differ from analogous soils in other locations in a higher bulk content of calcium, a close to neutral reaction, and a relatively high degree of base saturation. Gray-humus residually calcareous soils (AO-AYca-Cca) developed from calcareous deposits have a neutral or slightly alkaline reaction; their exchange complex is almost completely saturated with bases. The soils that developed from both marine and moraine deposits are generally similar in their major genetic features. The profiles of all the soils are not differentiated with respect to the contents of major elements, including oxalate-soluble forms of aluminum and iron. Gley features are also absent in the profiles of these soils.

  8. [Effects of different soil types on the foliar δ13C values of common local plant species in karst rocky desertification area in central Guizhou Province].

    Science.gov (United States)

    Du, Xue-lian; Wang, Shi-jie; Luo, Xu-qiang

    2014-09-01

    By measuring the foliar δ13C values of common local plant species grown in different soil types in Wangjiazhai catchments, a typical karst desertification area in Qingzhen City, Central Guizhou, we studied the impact of soil type and rocky desertification grade on the foliar δ13C values. The results showed that the foliar δ13C values were more negative in yellow soil area than those in black calcareous area and there was no obvious difference in foliar δ13C values between these two soil types. The distribution interval of foliar δ13C values in yellow soil area was narrower than those in black calcareous area and the variation coefficient of foliar δ13C values in yellow soil area were smaller than those in black calcareous area. With increasing degree of karst rocky desertification, the foliar δ13C values of plant community in black calcareous area increased, whereas those in yellow soil area first increased and then decreased. The result of multiple comparison showed that the difference in foliar δ13C values of plant community among rocky desertification grade was not obvious in yellow soil area, but it was obvious in black calcareous area. Correlation analysis between the foliar δ13C values of plant species and the main environmental factors indicated that slope and soil thickness were the main factors which affected the foliar δ13C values of plants in yellow soil area and soil water contant was the main factor in black calcareous area. The impact of soil on the foliar δ13C values was realized by adjusting the soil moisture in study area.

  9. Production and carbonate dynamics of Halimeda incrassata (Ellis) Lamouroux altered by Thalassia testudinum Banks and Soland ex König

    Science.gov (United States)

    Barry, S.; Frazer, T.; Jacoby, C.

    2013-05-01

    Ocean acidification poses a serious threat to a broad suite of calcifying organisms. Scleractinian corals and calcareous algae that occupy shallow, tropical waters are vulnerable to global changes in ocean chemistry because they already are subject to stressful and variable carbon dynamics at the local scale. For example, net heterotrophy increases carbon dioxide concentrations, and pH varies with diurnal fluctuations in photosynthesis and respiration. Few researchers, however, have investigated the possibility that carbon dioxide consumption during photosynthesis by non-calcifying photoautotrophs, such as seagrasses, can ameliorate deleterious effects of ocean acidification on sympatric calcareous algae. Naturally occurring variations in the density of seagrasses and associated calcareous algae provide an ecologically relevant test of the hypothesis that diel fluctuations in water chemistry driven by cycles of photosynthesis and respiration within seagrass beds create microenvironments that enhance macroalgal calcification. In Grape Tree Bay off Little Cayman Island BWI, we quantified net production and characterized calcification for thalli of the calcareous green alga Halimeda incrassata growing within beds of Thalassia testudinum with varying shoot densities. Results indicated that individual H. incrassata thalli were ~6% more calcified in dense seagrass beds. On an areal basis, however, far more calcium carbonate was produced by H. incrassata in areas where seagrasses were less dense due to higher rates of production. In addition, diel pH regimes in vegetated and unvegetated areas within the lagoon were not significantly different, suggesting water exchange and mixing throughout the lagoon. These results suggest that, especially in well-mixed lagoons, carbonate production by calcareous algae may be more related to biotic interactions between seagrasses and calcareous algae than to seagrass-mediated changes in local water chemistry.

  10. Determination of inositol phosphate ester in lake sediments

    International Nuclear Information System (INIS)

    Weimer, W.C.; Armstrong, D.E.

    1977-01-01

    A procedure for the determination of the total inositol polyphosphate content of lake sediments is presented and evaluated. This technique involves extraction with NaOH, cleanup of the extract, and isolation and identification of two groups of inositol phosphate esters by ion-exchange chromatography. Radioisotope dilution is employed to correct for losses during the extraction, cleanup and isolation steps. Recoveries of the radiotracer inositol phosphates have averaged 85% during the analysis of approximately 40 calcareous and non-calcareous sediment samples and more than 20 soil samples

  11. Effect of gamma irradaition on growth and nutrients uptake of sorghum plants

    International Nuclear Information System (INIS)

    Eleiwa, M.E.; Rabie, M.H.

    1994-01-01

    A pot experiment was carried out using sandy calcareous soils to study the effects of gamma irradiating doses for sorghum seeds on dry matter yield and elemental uptake. Three cuttings were taken during the experiment every 40 days. Results showed that 4 Kr. dose was the best dose that caused significant higher increase of dry matter yield and nutrients uptake for three cuttings under both types of soil. Gamma irradiation doses at 8 Kr. and above all had an adverse affect on dry matter yield and nutrients uptake, especially under calcareous soil. (author)

  12. Irradiated sewage sludge for increased crop production - III. Macronutrient availability

    International Nuclear Information System (INIS)

    El-Motaium, R.; Badawy, S.H.

    2002-01-01

    Irradiated and non-irradiated sewage sludge, from El-Gabal El-Asfar Farm near Cairo, were applied to tomato (Lycopersicon esculentum cv. GS) grown in a calcareous and a sandy soil at rates of 20, 40, 60, and 80 t/ha. Unfertilized controls and basal-fertilizer treatments were included. Total concentrations of micronutrients (Cu, Zn, Fe, Mn) in sludge-treated calcareous soil were higher than those in the sandy soil, although DTPA-extractable micronutrient concentrations were lower. There were no significant differences between irradiated and non-irradiated sludge treatments in DTPA-extractable and total micronutrient concentrations for the calcareous or the sandy soil. The total micronutrient concentrations for the highest sludge application rate (80 t/ha) were 5,108, 125, 68.2, and 207 μg/g in the calcareous soil and 2,200, 74.8, 43.2, and 139 μg/g in the sandy soil for Fe, Mn, Cu, and Zn, respectively, whereas the DTPA-extractable micronutrient concentrations were 25.0, 6.2, 5.5 and 6.6 μg/g in the calcareous soil and 53.3, 10.1, 7.3 and 9.83 μg/g in the sandy soil, respectively. Highly significant differences were observed in total and available micronutrient concentrations in calcareous and sandy soils among the sludge-application rates. Micronutrient concentrations of tomato leaves and fruits increased with increasing application rates of irradiated and non-irradiated sludge, and were higher in the sandy than in the calcareous soil for the same treatment. Highly significant differences were observed among the sludge-application rates in terms of the concentrations of micronutrients in both leaves and fruits. However, there were no significant differences between the irradiated and non-irradiated sludge treatments in the micronutrient concentrations of leaves and fruits in either soil. Micronutrient uptake increased with increasing rates of application of sludge to the soil, more so in the sandy than in the calcareous soil. The amounts of Fe, Mn, Cu, and Zn

  13. Irradiated sewage sludge for increased crop production - III. Macronutrient availability

    International Nuclear Information System (INIS)

    El-Motaium, R.; Badawy, S.H.

    2002-01-01

    Irradiated and non-irradiated sewage sludge, from El-Gabal El-Asfar Farm near Cairo, were applied to tomato (Lycopersicon esculentum cv. GS) grown in a calcareous and a sandy soil at rates of 20, 40, 60, and 80 t/ha. Unfertilized controls and basal-fertilizer treatments were included. Total concentrations of micronutrients (Cu, Zn, Fe, Mn) in sludge-treated calcareous soil were higher than those in the sandy soil, although DTPAextractable micronutrient concentrations were lower. There were no significant differences between irradiated and non-irradiated sludge treatments in DTPA-extractable and total micronutrient concentrations for the calcareous or the sandy soil. The total micronutrient concentrations for the highest sludge application rate (80 t/ha) were 5,108, 125, 68.2, and 207 μg/g in the calcareous soil and 2,200, 74.8, 43.2, and 139 μg/g in the sandy soil for Fe, Mn, Cu, and Zn, respectively, whereas the DTPA-extractable micronutrient concentrations were 25.0, 6.2, 5.5 and 6.6 μg/g in the calcareous soil and 53.3, 10.1, 7.3 and 9.83 μg/g in the sandy soil, respectively. Highly significant differences were observed in total and available micronutrient concentrations in calcareous and sandy soils among the sludge-application rates. Micronutrient concentrations of tomato leaves and fruits increased with increasing application rates of irradiated and non-irradiated sludge, and were higher in the sandy than in the calcareous soil for the same treatment. Highly significant differences were observed among the sludge-application rates in terms of the concentrations of micronutrients in both leaves and fruits. However, there were no significant differences between the irradiated and non-irradiated sludge treatments in the micronutrient concentrations of leaves and fruits in either soil. Micronutrient uptake increased with increasing rates of application of sludge to the soil, more so in the sandy than in the calcareous soil. The amounts of Fe, Mn, Cu, and Zn

  14. Regional radiometric map of Syria, using gamma-ray spectrometer

    International Nuclear Information System (INIS)

    Aissa, M.; Al-Hent, R.; Nasser, R.

    2005-01-01

    The regional radiometric gamma-ray spectrometry map of Syria, scaled 1/1000000, for surficial concentration of the total radioactivity (Ur), eU, eTh and %K was completely achieved after normalizing the airborne and carbon data sets to match each other. It worthy notice that, the anomalies found to be closely related to either phosphate and/or glauconite deposits. It is worth mentioning that throughout the survey work many scattered occurrences of secondary uranium mineralization were found as spots in some formations and phosphate rocks. Where this phenomena attributes to chemical and physical disseminating instead of accumulating the radioelements. So, that leads to a weak expectation for usual surface uranium deposits where attributed to the oxidizing condition. Then this expectation remains, as an open question requires answering through planning to subsurface prospecting. (Author)

  15. Area balance and strain in an extensional fault system: Strategies for improved oil recovery in fractured chalk, Gilbertown Field, southwestern Alabama -- Year 2. Annual report, March 1997--March 1998

    Energy Technology Data Exchange (ETDEWEB)

    Pashin, J.C.; Raymond, D.E.; Rindsberg, A.K.; Alabi, G.G.; Carroll, R.E.

    1998-09-01

    Gilbertown Field is the oldest oil field in Alabama and has produced oil from fractured chalk of the Cretaceous Selma Group and glauconitic sandstone of the Eutaw Formation. Nearly all of Gilbertown Field is still in primary recovery, although waterflooding has been attempted locally. The objective of this project is to analyze the geologic structure and burial history of Mesozoic and Tertiary strata in Gilbertown Field and adjacent areas in order to suggest ways in which oil recovery can be improved. Indeed, the decline of oil production to marginally economic levels in recent years has made this type of analysis timely and practical. Key technical advancements being sought include understanding the relationship of requisite strain to production in Gilbertown reservoirs, incorporation of synsedimentary growth factors into models of area balance, quantification of the relationship between requisite strain and bed curvature, determination of the timing of hydrocarbon generation, and identification of the avenues and mechanisms of fluid transport.

  16. Upper Proterozoic (1800-570 Ma) stratigraphy: a survey of lithostratigraphic, paleontological, radiochronological and magnetic correlations

    International Nuclear Information System (INIS)

    Trompette, R.

    1982-01-01

    Classical stratigraphy which was conceived in relation to the Phanerozoic, can be extended into the Precambrian, particularly the upper part. Stromatolite biostratigraphy provides natural subdivisions of the Upper Proterozoic, as indicated by studies on the Riphean of the U.S.S.R. The correlation techniques are identical to those used in the Phanerozoic. Imperfections in the biostratigraphic record, however, have encouraged the development of lithostratigraphic, radiochronological and paleomagnetic techniques. The possibility of dating argillaceous sedimentary rocks largely depends on the care taken in the selection of samples. The samples should have the necessary mineralogy and should not contain inherited 40 Ar or 87 Sr. Good results have been obtained on glauconites rich in K 2 O and particularly on illite and smectite, using the Rb-Sr method. Geochronology is the most precise of the four methods of correlation considered. It also provides a framework on which to hang the results of lithostratigraphy and magnetostratigraphy. (Auth.)

  17. Rock-physics modelling of the North Sea greensand

    DEFF Research Database (Denmark)

    Hossain, Zakir

    cemented, whereas Ty Formation is characterized by microcrystalline quartz cement. A series of laboratory experiments including core analysis, capillary pressure measurements, NMR T2 measurements, acoustic velocity measurements, electrical properties measurements and CO2 injection experiments were done...... cementation and berthierine cementation. Initially greensand is a mixture of mainly quartz and glauconite; when weakly cemented, it has relatively low elastic modulus and can be modeled by a Hertz-Mindlin contact model of two types of grains. Silica-cemented greensand has a relatively high elastic modulus...... and can be modeled by an intermediate-stiff-sand or a stiff-sand model. Berthierine cement has a different growth patterns in different part of the greensand, resulting in a soft-sand model and an intermediate-stiff-sand model. The second rock-physical model predicts Vp-Vs relations and AVO of a greensand...

  18. Pathways for arsenic from sediments to groundwater to streams: Biogeochemical processes in the Inner Coastal Plain, New Jersey, USA

    Science.gov (United States)

    Barringer, Julia L.; Mumford, Adam; Young, Lily Y.; Reilly, Pamela A.; Bonin, Jennifer L.; Rosman, Robert

    2010-01-01

    The Cretaceous and Tertiary sediments that underlie the Inner Coastal Plain of New Jersey contain the arsenic-rich mineral glauconite. Streambed sediments in two Inner Coastal Plain streams (Crosswicks and Raccoon Creeks) that traverse these glauconitic deposits are enriched in arsenic (15–25 mg/kg), and groundwater discharging to the streams contains elevated levels of arsenic (>80 μg/L at a site on Crosswicks Creek) with arsenite generally the dominant species. Low dissolved oxygen, low or undetectable levels of nitrate and sulfate, detectable sulfide concentrations, and high concentrations of iron and dissolved organic carbon (DOC) in the groundwater indicate that reducing environments are present beneath the streambeds and that microbial activity, fueled by the DOC, is involved in releasing arsenic and iron from the geologic materials. In groundwater with the highest arsenic concentrations at Crosswicks Creek, arsenic respiratory reductase gene (arrA) indicated the presence of arsenic-reducing microbes. From extracted DNA, 16s rRNA gene sequences indicate the microbial community may include arsenic-reducing bacteria that have not yet been described. Once in the stream, iron is oxidized and precipitates as hydroxide coatings on the sediments. Arsenite also is oxidized and co-precipitates with or is sorbed to the iron hydroxides. Consequently, dissolved arsenic concentrations are lower in streamwater than in the groundwater, but the arsenic contributed by groundwater becomes part of the arsenic load in the stream when sediments are suspended during high flow. A strong positive relation between concentrations of arsenic and DOC in the groundwater samples indicates that any process—natural or anthropogenic—that increases the organic carbon concentration in the groundwater could stimulate microbial activity and thus increase the amount of arsenic that is released from the geologic materials.

  19. Characterization of fieldstone for a provenance study of local building stones and artifacts

    Science.gov (United States)

    Goossens, M.; De Kock, T.; Dewanckele, J.; Boone, M.; De Boever, W.; Brabant, L.; Louwye, S.; De Ceukelaire, M.; Vanhaecke, F.; Cnudde, V.

    2012-04-01

    Fieldstone is a Belgian silicified sandstone speckled with glauconite. The hardness varies with the degree of silicification and its colour, which is usually greenish, can differ from bluish gray to orange depending on the degree of oxidation of the glauconite. Although recently discovered in the clayey interlayers, fieldstone mainly appears in the sandy units of the Eocene in Western Flanders (Belgium). It occurs as lenses and banks parallel to the stratification. From Roman times onwards, these were locally intensely cultivated as local building stones. Furthermore archeological evidence points out fieldstone was used in prehistoric times to make various artifacts like scrapers and jacks. The purpose of our study is to characterize fieldstone from the different known geographical and stratigraphical localities. Ambiguous stratigraphical classifications of fieldstone outcrops in the past have complicated previous studies of fieldstone. Therefore, we aim to provide clarity over its stratigraphical occurrence and deliver additional information about its formation. The ultimate goal is to trace back the origin of the fieldstone used in buildings and for archeological artifacts to a distinct locality. For the characterization of the fieldstone different techniques were used. Thin sections were examined by petrographical microscopy in order to study grain size, porosity, mineralogy, degree of silicification and in some samples microfossil content like silicified foraminifers. Porosity was determined with volumetric analysis and high resolution X-ray computer tomography. Attention towards the dinoflagellate content was given. This can provide information about the age and depositional environment of the silicified sands. In addition, it can act as a distinct feature that is characteristic for one locality or stratigraphic layer. A selected amount of samples were chemically analysed with Laser Ablation Inductively Coupled Plasma Mass Spectrometer in order to check if

  20. The Role of Teak Leaves (Tectona grandis), Rhizobium, and Vesicular-Arbuscular Mycorrhizae on Improving Soil Structure and Soil Nutrition

    Science.gov (United States)

    Yuliani; Rahayu, Y. S.

    2018-01-01

    Calcium is the largest mineral in calcareous soils. High levels of calcium carbonate lead to phosphate deposition. Nutrient deficiencies in calcareous soil (mainly Phosphate and Nitrogen) resulted only certain crops with a wide range of tolerances that can grow. Meanwhile, dynamics nutrient in calcareous soils also depend on the topography and decomposition of the litter in the growing vegetation. The purpose of this study was to describe the pattern of nutrient enhancement and soil-texture structures on calcareous soils after littering the teak leaves, Rhizobium and Vesicular Arbuscular Mycorrhiza. The research parameters were the concentration of N, P, K; C/N ratio, humid acid content, and soil structure, which measured at days 30, 60, and 85 of soil decomposition process. The results showed that at days 30, the texture and structure of the soil tend to be stable (porosity 31.2, DMR 1.93, moisture content 0.36, sandy clay) while at days 85 has been very stable (porosity 49.8; Water content 0.28, sandy clay). While C and N organic, N and K concentration at days 30 showed low value (C organic 1.03, N 0.12, K 0.49, C / N ratio 9). This condition is almost unchanged at days 85. While the P value shows very high value (60.53) at days 30 although after 60 days the P content showed a decrease.

  1. Physical and chemical protection of soil organic carbon in three agricultural soils with different contents of calcium carbonate

    International Nuclear Information System (INIS)

    Clough, A.; Skjemstad, J.O.

    2000-01-01

    The amount of organic carbon physically protected by entrapment within aggregates and through polyvalent cation organic matter bridging was determined on non-calcareous and calcareous soils. The composition of organic carbon in whole soils and 13 C NMR analysis. High energy photo-oxidation was carried out on <53 μm fractions and results from the NMR spectra showed 17-40% of organic carbon was in a condensed aromatic form, most likely charcoal (char). The concept that organic material remaining after photo-oxidation may be physically protected within aggregates was investigated by treating soils with a mild acid prior to photo-oxidation. More organic material was protected in the calcareous than the non-calcareous soils, regardless of whether the calcium occurred naturally or was an amendment. Acid treatment indicated that the presence of exchangeable calcium reduced losses of organic material upon photo-oxidation by about 7% due to calcium bridging. These results have implications for N fertiliser recommendations based upon organic carbon content. Firstly, calcium does not impact upon degradability of organic material to an extent likely to affect N fertiliser recommendations. Secondly, standard assessment techniques overestimate active organic carbon content in soils with high char content. Copyright (2000) CSIRO Publishing

  2. Effects of sulfur and nitrogen on nutrients uptake of corn using ...

    African Journals Online (AJOL)

    Jane

    2011-08-08

    Aug 8, 2011 ... Sulfur uptake efficiency increases, and the deficiency symptom disappears, upon application of N fertilizer in the form of urea in S deficient soil (Murphy, 1999). Sulfur is considered one of the major essential plant nutrients and an amendment used for reclaiming alkaline and calcareous soils (Marschner ...

  3. Surface water dynamics in the Reykjanes Ridge area during the Holocene as revealed by coccolith assemblages

    NARCIS (Netherlands)

    Balestra, B.; Ziveri, P.; Baumann, K. H.; Troelstra, S.R.; Monechi, S.

    2010-01-01

    The calcareous nannofossil assemblages from sediment core DS97-2P from the Reykjanes Ridge have been investigated to document oceanographic changes in surface water during the Holocene. The recorded variations in coccolithophore species assemblages and accumulation rates indicate that the region was

  4. Copper bioavailability and extractability as related to chemical properties of contaminated soils from a vine-growing area

    International Nuclear Information System (INIS)

    Chaignon, V.; Sanchez-Neira, I.; Herrmann, P.; Jaillard, B.; Hinsinger, P.

    2003-01-01

    Root Cu concentration is a good indicator of soil Cu bioavailability. - Vineyard soils have been contaminated by Cu as a consequence of the long-term use of Cu salts as fungicides against mildew. This work aimed at identifying which soil parameters were the best related to Cu bioavailability, as assessed by measuring the concentrations of Cu in shoots and roots of tomato cropped (in lab conditions) over a range of 29 (24 calcareous and five acidic) Cu-contaminated topsoils from a vine-growing area (22-398 mg Cu kg -1 ). Copper concentrations in tomato shoots remained in the adequate range and were independent of soil properties and soil Cu content. Conversely, strong, positive correlations were found between root Cu concentration, total soil Cu, EDTA- or K-pyrophosphate-extractable Cu and organic C contents in the 24 calcareous soils, suggesting a prominent role of organic matter in the retention and bioavailability of Cu. Such relations were not observed when including the five acidic soils in the investigated population, suggesting a major pH effect. Root Cu concentration appeared as a much more sensitive indicator of soil Cu bioavailability than shoot Cu concentration. Simple extractions routinely used in soil testing procedures (total and EDTA-extractable Cu) were adequate indicators of Cu bioavailability for the investigated calcareous soils, but not when different soil types were considered (e.g. acidic versus calcareous soils)

  5. Investigation of Copper Sorption by Sugar Beet Processing Lime Waste

    Science.gov (United States)

    In the western United States, sugar beet processing for sugar recovery generates a lime-based waste product (~250,000 Mg yr-1) that has little liming value in the region’s calcareous soils. This area has recently experienced an increase in dairy production, with dairi...

  6. Effects of microelements on soil nematode assemblages seven years after contaminating an agricultural field

    NARCIS (Netherlands)

    Nagy, P.; Bakonyi, G.; Bongers, A.M.T.; Kádár, I.; Fábián, M.; Kiss, I.

    2004-01-01

    Long-term effects of Cd, Cr, Cu, Se and Zn were studied 7 years after artificially contaminating plots of an agricultural field on a calcareous chernozem soil. Effects of three to four different contamination levels (originally 10, 30, 90 and 270 mg kg(-1)) were studied. Nematode density was

  7. Short exposure to acetylene to distinguish between nitrifier and denitrifier nitrous oxide production in soil and sediment samples

    NARCIS (Netherlands)

    Kester, R.A.; Boer, W. de; Laanbroek, H.J.

    1996-01-01

    The contribution of nitrifiers and denitrifiers to the nitrous oxide production in slurries of calcareous silt loam and river bank sediment at different oxygen concentrations was determined using acetylene as nitrification inhibitor. The addition of 10 Pa acetylene resulted in inhibition of

  8. Short exposure to acetylene to distinguish between nitrifier and denitrifier nitrous oxide production in soil and sediment samples

    NARCIS (Netherlands)

    Kester, R.A.; De Boer, W.; Laanbroek, H.J.

    1996-01-01

    The contribution of nitrifiers and denitrifiers to the nitrous oxide production in slurries of calcareous silt loam and river bank sediment at different oxygen concentrations was determined using acetylene as nitrification inhibitor. The addition of 10 Pa acetylene resulted in inhibition of nitrous

  9. A new fossil-lagerstätte from the lower eocene of lessini mountains (northern Italy): A multidisciplinary approach

    NARCIS (Netherlands)

    Giusberti, L.; Bannikov, A.; Boscolo Galazzo, F.; Fornaciari, E.; Frieling, J.|info:eu-repo/dai/nl/338017909; Luciani, V.; Papazzoni, C.A.; Roghi, G.; Schouten, S.|info:eu-repo/dai/nl/137124929; Sluijs, A.|info:eu-repo/dai/nl/311474748; Bosellini, F.R.; Zorzin, R.

    2014-01-01

    Hemipelagic dark limestones within calciturbiditic deposits at Monte Solane in the western Lessini Mountains of northern Italy yield a fish fauna dominated by stomiiforms. A minor component of the fossil assemblage is represented by a macroalgal non-calcareous flora associated with rarer terrestrial

  10. A new

    NARCIS (Netherlands)

    Giusberti, L.; Bannikov, A.; Galazzo, F.B.; Fornaciari, E.; Frieling, J.; Luciani, V.; Papazzoni, C.A.; Roghi, G.; Schouten, S.; Sluijs, A.; Bosellini, F.R.; Zorzin, R.

    2014-01-01

    Hemipelagic dark limestones within calciturbiditic deposits at Monte Solane in the western Lessini Mountains of northern Italy yield a fish fauna dominated by stomiiforms. A minor component of the fossil assemblage is represented by a macroalgal non-calcareous flora associated with rarer terrestrial

  11. 40 CFR 230.44 - Coral reefs.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 24 2010-07-01 2010-07-01 false Coral reefs. 230.44 Section 230.44... Aquatic Sites § 230.44 Coral reefs. (a) Coral reefs consist of the skeletal deposit, usually of calcareous... organisms present in growing portions of the reef. (b) Possible loss of values: The discharge of dredged or...

  12. Interacting effects of grazing and habitat conditions on seedling recruitment and establishment

    Czech Academy of Sciences Publication Activity Database

    Kladivová, A.; Münzbergová, Zuzana

    2016-01-01

    Roč. 27, č. 4 (2016), s. 834-843 ISSN 1100-9233 R&D Projects: GA ČR(CZ) GA15-11635S Institutional support: RVO:67985939 Keywords : calcareous grassland * soil depth * species composition * Ellenberg indicator values * seedling mortality * browsing * seedling survival * Czech carst Subject RIV: EF - Botanics Impact factor: 2.924, year: 2016

  13. Effect of carbonate chemistry alteration on the early embryonic development of the Pacific oyster (Crassostrea gigas)

    NARCIS (Netherlands)

    Gazeau, F.; Gattuso, J.-P.; Greaves, M.; Elderfield, H.; Peene, J.; Heip, C.H.R.; Middelburg, J.J.

    2011-01-01

    Ocean acidification, due to anthropogenic CO2 absorption by the ocean, may have profound impacts on marine biota. Calcareous organisms are expected to be particularly sensitive due to the decreasing availability of carbonate ions driven by decreasing pH levels. Recently, some studies focused on

  14. Effect of Carbonate Chemistry Alteration on the Early Embryonic Development of the Pacific Oyster (

    NARCIS (Netherlands)

    Gazeau, F.; Gattuso, J.P.; Greaves, M.; Elderfield, H.; Peene, J.; Heip, C.H.R.; Middelburg, J.J.

    2011-01-01

    Ocean acidification, due to anthropogenic CO(2) absorption by the ocean, may have profound impacts on marine biota. Calcareous organisms are expected to be particularly sensitive due to the decreasing availability of carbonate ions driven by decreasing pH levels. Recently, some studies focused on

  15. Effect of carbonate chemistry alteration on the early embryonic development of the pacific pyster (Crassostrea gigas)

    NARCIS (Netherlands)

    Gazeau, F.P.H.; Gattuso, J.P.; Greaves, M.; Elderfield, H.; Peene, J.; Heip, C.H.R.; Middelburg, J.J.

    2011-01-01

    Ocean acidification, due to anthropogenic CO(2) absorption by the ocean, may have profound impacts on marine biota. Calcareous organisms are expected to be particularly sensitive due to the decreasing availability of carbonate ions driven by decreasing pH levels. Recently, some studies focused on

  16. Research Article

    African Journals Online (AJOL)

    2016-06-05

    Jun 5, 2016 ... The treated wastewater in irrigation water volume ... municipal wastewater treatment plant, which since 1386 has started to collect and ..... of the soil, MA Thesis, Department of Water Engineering University of Kerman Islamic .... municipal solid waste compost on trace metal leaching in calcareous soils.

  17. First record of Citheronia regalis (Lepidoptera: Saturniidae) feeding on Cotinus obovatus (Anacardiaceae)

    DEFF Research Database (Denmark)

    Graves, Gary R.

    2017-01-01

    Summary The regal moth (Citheronia regalis F.; Lepidoptera: Saturniidae) is reported for the first time feeding on foliage of the American smoketree (Cotinus obovatus Raf.; Anacardiaceae), an endemic tree with a relictual distribution on calcareous soils in the southern United States. This record...

  18. Iron fertilization with FeEDDHA : the fate and effectiveness of FeEDDHA chelates in soil-plant systems

    NARCIS (Netherlands)

    Schenkeveld, W.D.C.

    2010-01-01

    Iron deficiency chlorosis is a nutritional disorder in plants which reduces crop yields both quantitatively and qualitatively, and causes large economic losses. It occurs world-wide, predominantly in plants grown on calcareous soils, as a result of a limited bioavailability of iron related to the

  19. Evaluation of the potential impact of Cu competition on the performance of o,o-FeEDDHA in soil applications

    NARCIS (Netherlands)

    Schenkeveld, W.D.C.; Weng, L.P.; Reichwein, A.M.; Temminghoff, E.J.M.; Riemsdijk, van W.H.

    2015-01-01

    Ferric ethylene diamine-N,N'-bis(hydroxy phenyl acetic acid) (FeEDDHA)-based iron (Fe) fertilizers are commonly applied to plants grown on calcareous soils and comprise a mixture of FeEDDHA components. Upon application to the soil, the pore water concentrations of the active ingredients racemic

  20. The effectiveness of soil-applied FeEDDHA treatments in preventing iron chlorosis in soybean as a function of the 0,0-FeEDDHA content

    NARCIS (Netherlands)

    Schenkeveld, W.D.C.; Dijcker, R.; Reichwein, A.M.; Temminghoff, E.J.M.; Riemsdijk, van W.H.

    2008-01-01

    The application of FeEDDHA products is the most common practice to prevent or to remedy Fe chlorosis in crops grown on calcareous soils. These products consist of a mixture of EDDHA components chelated to Fe. In this study such mixtures have been divided into four (groups of) components: racemic