WorldWideScience

Sample records for calcareous soils

  1. Hardwood biochar influences calcareous soil physicochemical and microbiological status

    Science.gov (United States)

    The effects of biochar application to calcareous soils are not well documented. In a laboratory incubation study, a hardwood-based, fast pyrolysis biochar was applied (0, 1, 2, and 10% by weight) to a calcareous soil. Changes in soil chemistry, water content, microbial respiration, and microbial com...

  2. Organic matter dynamics in coarse sandy calcareous soils

    NARCIS (Netherlands)

    Pronk, A.A.; Reuler, van H.

    2011-01-01

    The decomposition of organic matter in coarse sandy calcareous soils (beach sand) is thought to be much higher than in acid fine sandy soils but relatively little research is performed on these soils. Laboratory incubation experiments in which the release of soil carbon (C) is determined may overest

  3. 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).

  4. Mobile nickel content in calcareous black soils of Rajac

    Directory of Open Access Journals (Sweden)

    Đorđević Aleksandar R.

    2002-01-01

    Full Text Available A description of mobile Ni contents in various subtypes of calcareous black soils from the area of the mountain massif of Rajac, is given in the present paper. A hundred soil samples were analysed in all, originating from four subtypes of calcareous black soil (organogenic, organo-mineral, brownized and loessivized black soils. The extraction of mobile Ni was carried out with 1.0 N HCl and its content was determined by atomic absorption spectrophotometry. The obtained results indicate that mobile Ni content in the investigated soils varies within a wide range, from 5.0 to 251.3 mg/kg that it is very seldom (only in 3% of the investigated samples within the range from 5 to 7 mg/kg, that in over 90% of the 100 investigated samples it is higher than 10 mg/kg, and in almost 3/5 of the samples it is higher than 20 mg/kg. Calcareous black soils of Rajac massif have much higher mobile Ni content than previously investigated black soils from calcareous massif of Rtanj, which is, by all means, only partly due to their more severe dealkalization and acidification. In addition, here is undoubtedly apparent the influence of the geological substrate, i.e. of serpentine rocks that border the calcareous massif of Rajac.

  5. 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

  6. Kinetics of Cd Release from Some Contaminated Calcareous Soils

    Energy Technology Data Exchange (ETDEWEB)

    Sajadi Tabar, S.; Jalali, M., E-mail: jalali@basu.ac.ir [Bu-Ali Sina University, Department of Soil Science, College of Agriculture (Iran, Islamic Republic of)

    2013-03-15

    Contamination of soils with heavy metals may pose long-term risk to groundwater quality leading to health implications. Bioavailability of heavy metals, like cadmium (Cd) is strongly affected by sorption and desorption processes. The release of heavy metals from contaminated soils is a major contamination risks to natural waters. The release of Cd from contaminated soils is strongly influenced by its mobility and bioavailability. In this study, the kinetics of Cd desorption from ten samples of contaminated calcareous soils, with widely varying physicochemical properties, were studied using 0.01 M EDTA extraction. The median percentage of Cd released was about 27.7% of the total extractable Cd in the soils. The release of Cd was characterized by an initial fast release rate (of labile fractions) followed by a slower release rate (of less labile fractions) and a model of two first-order reactions adequately describes the observed release of Cd from the studied soil samples. There was positive correlation between the amount of Cd released at first phase of release and Cd in exchangeable fraction, indicating that this fraction of Cd is the main fraction controlling the Cd in the kinetic experiments. There was strongly negative correlation between the amount of Cd released at first and second phases of release and residual fraction, suggesting that this fraction did not contribute in Cd release in the kinetic experiments. The results can be used to provide information for evaluation of Cd potential toxicity and ecological risk from contaminated calcareous soils.

  7. Boron and Zinc Transport Through Intact Columns of Calcareous Soils

    Institute of Scientific and Technical Information of China (English)

    M. MAHMOOD-UL-HASSAN; M. S. AKHTAR; G. NABI

    2008-01-01

    Leaching of boron (B) and zinc (Zn) can be significant in some pedomorphic conditions, which can cause contamination of shallow groundwater and economic losses. Boron and Zn adsorption and transport was studied using 8.4 cm diameter ×28 cm long intact columns from two calcareous soil series with differing clay contents and vadose zone structures:Lyallpur soil series, clay loam (fine-silty, mixed, hyperthermic Ustalfic Haplargid), and Sultanpur soil series, sandy loam (coarse-silty, mixed, hyperthermic Ustollic Camborthid). The adsorption isotherms were developed by equilibrating soil with 0.01 mol L-1 CaCl2 aqueous solution containing varying amounts of B and Zn and were fitted to the Langmuir equation. The B and Zn breakthrough curves were fitted to the two-domain convective-dispersive equation. At the end of the leaching experiment, 0.11 L 10 g L-1 blue dye solution was also applied to each column to mark the flow paths.The Lyallpur soil columns had a slightly greater adsorption partition coefficient both for B and Zn than the Sultanpur soil columns. In the Lyallpur soil columns, B arrival was immediate but the peak concentration ratio (the concentration in solution at equilibrium/concentration applied) was lower than that in the Sultanpur soil columns. The breakthrough of B in the Sultanpur soil columns occurred after about 10 cm of cumulative drainage in both the columns; the rise in effluent concentration was fast and the peak concentration ratio was almost 1. Zinc leaching through the soil columns was very limited as only one column from the Lyallpur soil series showed Zn breakthrough in the effluent where the peak concentration ratio was only 0.05. This study demonstrates the effect of soil structure on B transport and has implications for the nutrient management in field soils.

  8. Silicomolybdenum Blue Colorimetric Determination of Available Si in Calcareous Soils

    Institute of Scientific and Technical Information of China (English)

    XUGUOHUA; ZHENGWENJUAN; 等

    1996-01-01

    This paper deals with the determination of available Si content in calcareous soils with Mo blue colorimetric analysis method.The experimental results showed that two acid reagents of sodium acetate buffering solution (pH 4) and 0.025 mol/L citric acid generally had a strong ability of extracting soil available Si,and theri soil filtrates were colorless,On the contrary,two alkaline extractants of 20 mg/mL sodium carbonate and 0.5 mol/L sodium bicarbonate only got a relevantly lower soil avaiable Si and theri extracts appeared deep color of organic and other pigments,which could be decolorized by adding certain amounts of P-free activated charcoal (about 0.1g/g soil),Int the procedure of Mo blue colorimetry,adding proper amount of oxalic acid and K(SbO)C4H4O6 could eliminate the interference of P to Si and Si to P,respectively.The concentration of acids was not the major factor suppressing the interferences between P and Si in the colorimetric analysis.In the medium of 0.2-0.8mole H×+/L sulfuric acid,the intensity of the silicomolybdate blue color did not vary with acidity,no matter whether(NH4)2 Fe(SO4)2 or ascorbic acid was used as reductive reagent.About 10 minutes was needed to from a fully blue complex at 20-25°C,After 30 minutes,the blue color would slowly change into light one,and hence,the colorimetric process should be finished within a short time.

  9. Recharge in northern clime calcareous sandy soils: soil water chemical and carbon-14 evolution

    Science.gov (United States)

    Reardon, E. J.; Mozeto, A. A.; Fritz, P.

    1980-11-01

    Chemical analyses were performed on soil water extracted from two cores taken from a sandy calcareous soil near Delhi, Ontario. Calcite saturation is attained within the unsaturated zone over short distances and short periods of time, whereas dolomite undersaturation persists to the groundwater table. The progressive dissolution of dolomite by soil water, within the unsaturated zone, after calcite saturation is reached results in calcite supersaturation. Deposition of iron and manganese oxyhydroxide phases occurs at the carbonate leached/unleached zone boundary. This is a result of soil water neutralization due to carbonate dissolution during infiltration but may also reflect the increased rate of oxidation of dissolved ferrous and manganous ions at higher pH's. The role of bacteria in this process has not been investigated. The depth of the carbonate leached/unleached zone boundary in a calcareous soil has important implications for 14C groundwater dating. The depth of this interface at the study site (-2 m) does not appear to limit 14C diffusion from the root zone to the depth at which carbonate dissolution occurs. Thus, soil water achieves open system isotopic equilibrium with the soil CO 2 gas phase. It is calculated that in soils with similar physical properties to the study soil but with depths of leaching of 5 m or more, complete 14C isotopic equilibration of soil water with soil gas would not occur. Soil water, under these conditions would recharge to the groundwater exhibiting some degree of closed system 14C isotopic evolution.

  10. BIO-DIAGNOSTICS OF STABILITY OF BROWN CALCAREOUS SOIL OF UTRISH NATURAL RESERVE TO CHEMICAL POLLUTION

    Directory of Open Access Journals (Sweden)

    Kolesnikov S. I.

    2015-10-01

    Full Text Available In this article, we have presented a number of modeling experiments to investigate the chemical pollution of brown calcareous soil. It assesses the stability of brown calcareous soil of a nature reserve called Utrish to contamination with heavy metals in biological parameters. Pollution of brown calcareous soil with Cr, Cu, Ni, Pb and oil causes a significant reduction in biological parameters. The degree of reduction depends on the nature of the contaminant and its concentration in the soil. The study showed that the indicators used in the biological condition of the soil, could be recommended for use for diagnosis, monitoring, and regulation of chemical pollution of brown soil. According to the degree of resistance to chemical contamination, the brown soils of Russia form the following series: typical brown - brown carbonate - brown leached

  11. Bioavailability of zinc and phosphorus in calcareous soils as affected by citrate exudation

    OpenAIRE

    Duffner, A.; Hoffland, E.; Temminghoff, E. J. M.

    2012-01-01

    Aims Zinc (Zn) and phosphorus (P) deficiency often occurs at the same time and limits crop production in many soils. It has been suggested that citrate root exudation is a response of plants to both deficiencies. We used white lupin (Lupinus albus L.) as a model plant to clarify if citrate exuded by roots could increase the bioavailability of Zn and P in calcareous soils. Methods White lupin was grown in nutrient solution and in two calcareous soils in a rhizobox. Rhizosphere soil solution wa...

  12. A simple, gravimetric method to quantify inorganic carbon in calcareous soils

    Science.gov (United States)

    Total carbon (TC) in calcareous soils has two components: inorganic carbon (IC) as calcite and or dolomite and organic carbon (OC) in the soil organic matter. The IC must be measured and subtracted from TC to obtain OC. Our objective was to develop a simple gravimetric technique to quantify IC. Th...

  13. Gravimetric Determination of Inorganic Carbon in Calcareous Soils Using the Carbonate-Meter

    Science.gov (United States)

    Organic carbon affects many important physical, chemical and microbiological soil properties. In calcareous soils, the inorganic carbon has to be measured and subtracted from the total carbon to obtain organic carbon. Our objective was to develop a gravimetric technique to quantify inorganic carbon ...

  14. 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 LacustrinePlain, has highly calcareous clayey sedimen

  15. 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.

  16. Estimation of the Biological Methods of Assessing Soil N-Supplying Capacity in Calcareous Soil

    Institute of Scientific and Technical Information of China (English)

    JIN Fa-hui; LI Shi-qing; LU Hong-ling; LI Sheng-xiu

    2007-01-01

    Although many biological methods are used to determine soil nitrogen supplying capacity, there are certain differences in the results for different types of soils and various ways of measurement due to the complexity of soil N conformation, the high variance of soil and microorganism, and the difference of environment. Therefore, it is not clear about which biologic incubation method is better for calcareous soil. In this study, pot experiments were performed by using 25 different calcareous surface soil samples on the Loess Plateau and taking the N uptake of wheat and corn with leaching soil initial nitrate and without leaching in pot experiments as the control to investigate the difference of eight biological incubation methods for reflecting soil nitrogen supply capacity. The eight biological methods are waterlogged incubation, aerobic incubation for 2 weeks and for 4 weeks, dry-wet alternation aerobic incubation for 2 weeks, long-term alternate leaching aerobic incubation (and N mineralization potential, N0), short-term leaching aerobic incubation, microbial biomass carbon (BC), and microbial biomass nitrogen (BN) method, respectively. Among these methods, the dry-wet alternation aerobic incubation and aerobic incubation for 4 weeks were the modification of the method of aerobic incubation for 2 weeks according to the actual farmland moisture. The results showed that the correlation coefficients between these methods and crop uptake N with leaching soil initial nitrate were 0.530, 0.700, 0.777, 0.768, 0.764 (and 0.790, N0), 0.650, 0.555, and 0.465, respectively (r0.05 = 0.369, r0.01 = 0.505). While without leaching soil initial nitrate, their coefficients were 0.351, 0.963, 0.962, 0.959, 0.825 (and 0.812, N0), 0.963, 0.289, and 0.095, respectively (r0.05=0.369, r0.01 =0.505). In conclusion,excluding the soil initial nitrate, the correlation coefficients between the eight methods and crop uptake N were, from high to low, N0, aerobic incubation for 4 weeks, dry

  17. Calcareous Sodic Soil Reclamation as Affected by Corn Stalk Application and Incubation:A Laboratory Study

    Institute of Scientific and Technical Information of China (English)

    LI Fa-Hu; R.KEREN

    2009-01-01

    A laboratory lysimeter experiment was conducted to investigate the effects of forage corn (Zea mays L.) stalk application on the CO2 concentration in soil air and calcareous sodic soil reclamation.The experimental treatments tested were soil exchangeable sodium percentage (ESP) levels of 1,11,and 19,added corn stalk contents of 0 to 36 g kg-1,and incubation durations of 30 and 60 days.The experimental results indicated that corn stalk application and incubation significantly increased CO2 partial pressure in soil profile and lowered pH value in soil solution,subsequently increased native CaCO3 mineral dissolution and electrolyte concentration of soil solution,and finally significantly contributed to reduction on soil sodicity level.The reclamation efficiency of calcareous sodic soils increased with the added corn stalk.When corn stalks were added at the rates of 22 and 34 g kg-1 into the soil with initial ESP of 19,its ESP value was decreased by 56% and 78%,respectively,after incubation of 60 days and the leaching of 6.5 pore volumes (about 48 L of percolation water) with distilled water.Therefore,crop stalk application and incubation could be used as a choice to reclaim moderate calcareous sodic soils or as a supplement of phytoremediation to improve reclamation efficiency.

  18. 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...... 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....

  19. Evidence For Different Reaction Pathways For Liquid And Granular Micronutrients In A Calcareous Soil

    Science.gov (United States)

    The benefits of Mn and Zn fluid fertilizers over conventional granular products in calcareous sandy loam soils have been agronomically demonstrated. We hypothesized that the differences in the effectiveness between granular and fluid Mn and Zn fertilizers is due to different Mn ...

  20. Changes in soil CO2 efflux of organic calcaric soils due to disturbance by wind

    Science.gov (United States)

    Mayer, M.; Katzensteiner, K.

    2012-04-01

    Disturbances such as windthrow or insect infestations are supposed to have a significant influence on the soil carbon balance of affected forests. Increasing soil temperatures and changes in the soil moisture regime, caused by the removed tree layer, are expected to change soil CO2 efflux, also known as soil respiration. Beside an anticipated stimulation of the carbon mineralization, the main part of root allocated CO2 is offset due to the blown down trees. On mountain forest sites of the Northern Limestone Alps, where highly active organic soils above calcareous parent material are characteristic (Folic Histosols and Rendzic Leptosols), an increase of the mineralization rate of carbon may contribute to enormous humus losses. Serious site degradation can be the consequence, especially on south exposed slopes where extreme climatic conditions occur. The present study tries to give insights to disturbance induced changes in temporal and spatial behaviour of soil respiration for a montane mountain forest located in the Northern Limestone Alps of Upper Austria. Soil respiration, soil temperature and volumetric water content were measured on two windthrow areas (blow down dates were 2007 and 2009 respectively) as well as in an adjacent mature mixed forest during the vegetation periods of 2010 and 2011. Soil respiration in both years was mainly driven by soil temperature, which explained up to 90 % of the concerning temporal variation. Volumetric water content had a significant influence as additional temporal driver. After removing the temperature trend, significant differences in basal soil respiration rates were found for the disturbance area and the forest stand. Inter seasonal declines in soil respiration were ascertained for the mature stand as well as for the recent windthrow. Particular decreases are related to drought stress in summer 2011 and a proceeded decomposition of labile soil carbon components at the windthrow site. An interaction between soil type and

  1. Manure and nitrogen application enhances soil phosphorus mobility in calcareous soil in greenhouses.

    Science.gov (United States)

    Yan, Zhengjuan; Chen, Shuo; Li, Junliang; Alva, Ashok; Chen, Qing

    2016-10-01

    Over many years, high phosphorus (P) loading for intensive vegetable cropping in greenhouses of North China has contributed to excessive P accumulation, resulting in environmental risk. In this study, the influences of manure and nitrogen (N) application on the transformation and transport of soil P were investigated after nine years in a greenhouse tomato double cropping system (winter-spring and autumn-winter seasons). High loading of manure significantly increased the soil inorganic P (Pi), inositol hexakisphosphate (IHP), mobile P and P saturation ratio (PSR, >0.7 in 0-30 cm depth soil; PSR was estimated from P/(Fe + Al) in an oxalate extract of the soil). The high rate of N fertilizer application to the studied calcareous soil with heavy loading of manure increased the following: (i) mobile organic P (Po) and Pi fractions, as evidenced by the decrease in the ratio of monoesters to diesters and the proportion of stable Pi (i.e., HCl-Pi) in total P (Pt) in 0-30 cm depth soil; (ii) relative distribution of Po in the subsoil layer; and (iii) P leaching to soil depths below 90 cm and the proportion of Po in Pt in the leachate. More acidic soil due to excessive N application increased P mobility and leaching. The increase in Ox-Al (oxalate-extractable Al) and the proportion of microbe-associated Po related to N application at soil depths of 0-30 cm suggested decrease in the net Po mineralization, which may contribute to downward transport of Po in the soil profile.

  2. Uptake of 137Cs by Leafy Vegetables and Grains from Calcareous Soils

    Energy Technology Data Exchange (ETDEWEB)

    Robison, W; Hamilton, T; Conrado, C; Kehl, S

    2004-04-19

    Cesium-137 was deposited on Bikini Island at Bikini Atoll in 1954 as a result of nuclear testing and has been transported and cycled in the ecosystem ever since. Atoll soils are of marine origin and are almost pure CaCO{sub 3} with high concentrations of organic matter in the top 40 cm. Data from previous experiments with mature fruit trees show very high transfer factors (TF's), [Bq g{sup -1} plant/ Bq g{sup -1} soil, both in dry weight] into fruits from atoll calcareous soil. These TF's are much higher than reported for continental, silica-based soils. In this report TF's for 5 types of leafy vegetable crops and 2 types of grain crops are provided for use in predictive dose assessments and for comparison with other data from other investigators working with other types of soil in the IAEA CRP ''The Classification of Soil Systems on the Basis of Transfer Factors of Radionuclides from Soil to Reference Plants''. Transfer factors for plants grown on calcareous soil are again very high relative to clay-containing soils and range from 23 to 39 for grain crops and 21 to 113 for leafy vegetables. Results from these experiments, in this unique, high pH, high organic content, low potassium (K) soil, provide a boundary condition for models relating soil properties to TF.

  3. 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.

  4. Effects of drought on cadmium accumulation in peanuts grown in a contaminated calcareous soil.

    Science.gov (United States)

    Xia, Shenglan; Wang, Xvming; Su, Genqiang; Shi, Gangrong

    2015-12-01

    This study aimed to investigate the effects of drought stress on cadmium (Cd) accumulation in peanut (Arachis hypogaea L.) grown in contaminated calcareous soils. Five peanut cultivars were grown in a calcareous soil spiked with 4 mg Cd kg(-1) soil (dry weight) under well-watered, mild drought, and severe drought conditions. The biomass production, gas exchange, spectral reflectance, and Cd accumulation in plant tissues were determined. The five cultivars significantly differed from each other in biomass production, gas exchange, spectral reflectance, and Cd accumulation. The effect of drought on Cd accumulation in peanuts varies with plant tissues, cultivars, and developmental stages. Drought decreased root Cd concentrations in seedlings of the two high Cd-accumulating cultivars (Haihua 1 and Zhenghong 3), which is associated with increasing leaf active Fe content. However, for the mature plants, drought stress caused an increase in Cd accumulation in roots, pod walls, and seeds depending on peanut cultivars. Negative correlations were found between seed Cd concentration and biomasses in both preflowering seedlings and mature plants. The seed Cd concentration in mature plants was also observed to be positively correlated with the shoot Cd concentration in preflowering seedlings. The increased Cd concentration in seeds of drought-stressed peanut plants grown in Cd-contaminated calcareous soils might be attributed to the drought-induced decrease of biomass production.

  5. 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.

  6. Wheat-Exuded Organic Acids Influence Zinc Release from Calcareous Soils

    Institute of Scientific and Technical Information of China (English)

    M. A. MAQSOOD; S. HUSSAIN; T. AZIZ; M. ASHRAF

    2011-01-01

    Rhizosphere drives plant uptake of sparingly soluble soil zinc (Zn).An investigation with three experiments was conducted to study organic acid exudation by two contrasting wheat genotypes (Sehar-06 and Vatan),Zn fractious in 10 different calcareous soils from Punjab,Pakistan,and release of different soil Zn fractions by organic acids.The two genotypes differed significantly in biomass production and Zn accumulation under deficient and optimum Zn levels in nutrient solution.At a deficient Zn level,Sehar-06 released more maleic acid in the rhizosphere than Vatan.Ten soils used in the present study had very different physicochemical properties; their total Zn and Zn distribution among different fractions varied significantly.Zinc release behaviour was determined by extracting the soils with 0.005 mol L-1 citric acid or maleic acid.The parabolic diffusion model best described Zn release as a function of time.Parabolic diffusion model fitting indicated more maleic acid-driven than citric acid-driven soil Zn mobility from different fractions.Cumulative Zn release in six consecutive extractions during 24 h ranged from 1.85 to 13.58 mg kg-1 using maleic acid and from 0.37 to 11.84 mg kg-1 using citric acid.In the selected calcareous soils,the results of stepwise linear regression indicated significant release of Fe-Mn oxide-bounded soil Zn by maleic acid and its availability to the Zn-efficient genotype.Hence,release of maleic acid by plants roots played an important role in phytoavailability of Zn from calcareous soils.

  7. 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...

  8. Contribution of Iron Phosphate in Calcareous Paddy Soils to Phosphorus Nutrition of Rice Plant

    Institute of Scientific and Technical Information of China (English)

    GUOZHI-FEN; TUSHU-XIN; 等

    1995-01-01

    A study was carried out on contribution of iron phosphate to phosphorus nutrition of rice plant under waterlogged and moist conditions,respectively,by use of synthetic Fe32 PO4.nH2O,tagging directly the iron phophate in calcareous paddy soils.Results showed that under waterlogged condition,similar to iron phosphate in acidic paddy soils.that in clacareous paddy soils was an important source of phosphorus to rice plant ,and the amount of phosphorus originated from it generally constituted 30-65% of the total phosphorus absorbed by rice plant.

  9. Effect of Organic Fertilizers on Soil Chemical Properties on Vineyard Calcareous Soil

    Directory of Open Access Journals (Sweden)

    Tomislav Karažija

    2015-12-01

    Full Text Available Organic fertilizers are an important contribution of organic matter that modify the physical, chemical and microbiological characteristics of the soil. The aim of investigation was to determine the effect of different organic fertilization on soil chemical properties on vineyard calcareous soil. Two-year fertilization trial was carried out in the Plešivica wine-growing region, in a 10-year old vineyard, cv. Sauvignon White grafted on Kobber 5BB rootstock, planted on soil with quite high pH for grapevine growing. The trial was performed according to randomize complete block design with 6 treatments (unfertilized, farmyard manure 20 t ha-1 and 40 t ha-1, peat 20 000 L ha-1 and 40 000 L ha-1, NPK 5-20-30 500 kg ha-1+200 kg UREA ha-1 in 4 repetitions. Statistically significant differences in soil reaction (pH in plowing layer (0-30 cm were found among fertilization treatments in the second year of studies. In the plowing layer (0-30 cm in both years of the study significant differences between the values of average total nitrogen content and available phosphorus as well were found, while there were no significant differences in the subplowing layer (30-60cm. Regarding to average value of fertilization treatment, statistically significant difference in the content of available potassium in plowing layer were found in the both investigated years, while in subplowing layer statistical differences were found in the first year of investigation only. Therefore, fertilization with different organic fertilizers significantly influenced the most of studied chemical properties of the soil, especially in plowing layer (0-30 cm.

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

    OpenAIRE

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

    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...

  11. The chemical characteristics of soil which determine phosphorus partitioning in highly calcareous soils

    Directory of Open Access Journals (Sweden)

    ANA TOPALOVIC

    2006-11-01

    Full Text Available Phosphorus fractions from three highly calcareous soils (average, 24.9 ± 4.8 %CO32- from sampling sites with aMediterranean climate were isolated by sequential extraction. In order to provide a more reliable basis for the definition of the obtained P-fractions, principal component analysis was applied and from the chemical characteristics of the 14 investigated soils, those characteristics which define the content and association features of the P-fractions were assessed. The soils are characterized by a relatively high pH (8.0 – 8.2 and by significantly differing contents of organic mater, acid-soluble Mg and total P. These differences affected the various association features of the P-fraction with the soil constituents. The NH4F–P fraction (isolated with 0.5 M NH4F, pH 8.2 is defined by the contents of the main metals of the oxide–hydroxide–clay associations (Al, Fe,Mn or by the the redox potential (Eh of Mn. The accumulation of NaOH–phosphorus (extractable with 0.1M NaOH depended on the constituents of the oxide–hydroxide–clay association, the humic substances and Eh-related factors. In those soils in whichNaOH–Pis defined by the oxide–hydroxide–clay assoiation, the participation of Fe as a bridge-forming metal is proposed. The main part of total P, i.e., DP = TP – (NH4F–P + NaOH–P is defined by the status of Mn– and Fe–humic complexes or by the concentration of hydroxyl-ions.

  12. 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 < 0.05) between the estimated K from multiple linear regression and measured K indicates that the use of calcium carbonate equivalent as a predictor variable gives a better estimation of K in areas with calcareous soils.

  13. Effect of Additional Carbonates on CO2 Emission from Calcareous Soil During the Closed-Jar Incubation

    Institute of Scientific and Technical Information of China (English)

    DONG Yan-Jie; CAI Miao; LIANG Bin; ZHOU Jian-Bin

    2013-01-01

    The closed-jar incubation method is widely used to estimate the mineralization of soil organic C.There are two C pools (i.e.,organic and inorganic C) in calcareous soil.To evaluate the effect of additional carbonates on CO2 emission from calcareous soil during closed-jar incubation,three incubation experiments were conducted by adding different types (CaCO3 and MgCO3) and amounts of carbonate to the soil.The addition of carbonates significantly increased CO2 emission from the soil; the increase ranged from 12.0% in the CaCO3 amended soil to 460% in the MgCO3 amended soil during a 100-d incubation.Cumulative CO2 production at the end of the incubation was three times greater in the MgCO3 amended soil compared to the CaCO3 amended one.The CO2 emission increased with the amount of CaCO3 added to the soil.In contrast,CO2 emission decreased as the amount of MgCO3 added to the soil increased.Our results confirmed that the closed-jar incubation method could lead to an overestimate of organic C mineralization in calcareous soils.Because of its effect on soil pH and the dissolution of carbonates,HgC12 should not be used to sterilize calcareous soil if the experiment includes the measurement of soil CO2 production.

  14. Influence of perennial plants on chemical properties of arid calcareous soils in Iran

    Energy Technology Data Exchange (ETDEWEB)

    Karimian, N.; Razmi, K. (Shiraz Univ. (Iran))

    1990-10-01

    The authors conducted a study in Bajgah to determine the influence of perennial plants on some selected properties of soils formed on the highly calcareous parent material. The major plant genera were determined to be Agropyron, Artemisia, Astragalus, Dianthus, Eryngium, Peganum, Polygonum, Stipa, and Thymus. Tops of plants genera were found to be significantly different in ash, N, P, K, Ca, Mg, Na, Mn, Zn, and Cu; the concentration of Fe was not significantly different. The authors found the plants to differ significantly in their influence on soil properties. Peganum caused an accumulation of organic matter (OM) as high as 7% in the soil, in an environment where the soils typically contain less than 1% OM. Soil concentrations of P, K, Mn, Zn, and Cu were also found to vary significantly beneath different plant genera. They suggest these differences in OM accumulation were caused by plant litter. Concentration of Fe in the soils formed beneath different plant genera was statistically unchanged.

  15. Organic Carbon Stabilization of Soils Formed on Acidic and Calcareous Bedrocks in Neotropical Alpine Grassland, Peru

    Science.gov (United States)

    Yang, Songyu; Cammeraat, Erik; Jansen, Boris; Cerli, Chiara; Kalbitz, Karsten

    2016-04-01

    Increasing evidence shows that Neotropical alpine ecosystems are vulnerable to global change. Since soils in the alpine grasslands of the Peruvian Andean region have large soil organic carbon (SOC) stocks, profound understanding of soil organic matter (OM) stabilization mechanisms will improve the prediction of the feedback between SOC stocks and global change. It is well documented that poor-crystalline minerals and organo-metallic complexes significantly contribute to the OM stabilization in volcanic ash soils, including those in the Andean region. However, limited research has focused on non-ash soils that also express significant SOC accumulation. A pilot study of Peruvian Andean grassland soils suggests that lithology is a prominent factor for such carbon accumulation. As a consequence of contrasting mineral composition and pedogenic processes in soils formed on different non-volcanic parent materials, differences in OM stabilization mechanisms may be profound and consequently may respond differently to global change. Therefore, our study aims at a further understanding of carbon stocks and OM stabilization mechanisms in soils formed on contrasting bedrocks in the Peruvian Andes. The main objective is to identify and compare the roles that organo-mineral associations and aggregations play in OM stabilization, by a combination of selective extraction methods and fractionations based on density, particle size and aggregates size. Soil samples were collected from igneous acidic and calcareous sedimentary bedrocks in alpine grassland near Cajamarca, Peru (7.17°S, 78.63°W), at around 3700m altitude. Samples were taken from 3 plots per bedrock type by sampling distinguishable horizons until the C horizons were reached. Outcomes confirmed that both types of soil accumulate large amounts of carbon: 405.3±41.7 t/ha of calcareous bedrock soil and 226.0±5.6 t/ha of acidic bedrock soil respectively. In addition, extremely high carbon contents exceeding 90g carbon per

  16. 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.

  17. Monoterpene and sesquiterpene emissions of three Mediterranean species through calcareous and siliceous soils in natural conditions

    Science.gov (United States)

    Ormeño, E.; Fernandez, C.; Bousquet-Mélou, A.; Greff, S.; Morin, E.; Robles, C.; Vila, B.; Bonin, G.

    Little is known about terpene emissions released by plants in response to abiotic factors, except for climate-related factors. Standard emissions ( ES) of monoterpenes ( ESM) and sesquiterpenes ( ESS) of Rosmarinus officinalis, Pinus halepensis and Cistus albidus in siliceous and calcareous sites were examined. Their dependency on some nutrients in these soils was also analyzed. The study was carried out in the south of France at the end of March, when C. albidus exhibited a leaf growth state, while the other two species exhibited a pre-budbreak state. The results revealed that ES of all major monoterpenes released by R. officinalis and ES of α-pinene and α-humulene of P. halepensis were higher in plants growing in calcareous soils. In contrast, for C. albidus, ESM and ES of β-bourbonene and α-humulene were higher in siliceous soils. ESM of all species was mainly correlated with nitrogen ( N) and available phosphorous (P A), while dependency on Ca 2+ or K + was variable. None of these nutrients was significantly correlated with ESS, suggesting that sesquiterpene synthesis pathway requires different nutrient supplies. While higher soil nutrient content stimulated ESM of R. officinalis and P. halepensis, it had a negative effect on ESM of C. albidus, probably because C. albidus exhibited a different phenological state. Considering the soil nature, and particularly N and P A as inputs in plant terpene inventories could hence contribute to obtain more accurate terpene estimates.

  18. Net transformation of phosphorus forms applied as inorganic and organic amendments to a calcareous soil

    Science.gov (United States)

    Audette, Yuki; O'Halloran, Ivan; Voroney, Paul

    2016-04-01

    The forms of phosphorus (P) in animal manure composts are different from that of synthetic P fertilizers, and this could affect how soil P chemistry will be altered when they are used as P amendments. The objective of this study was to analyze the net changes in the nature and dynamics of plant available P forms applied either as inorganic P (KH2PO4) or turkey litter compost (TLC) in calcareous soil with and without plant growth. Forms of TLC-P were characterized by x-ray diffraction and solution 31P NMR spectroscopy techniques. The amounts of various P forms in soils were measured by a sequential fractionation method after 4, 8, 12 and 16 weeks incubation. Brushite (Ca-P) and newberyite (Mg-P) were the major forms of inorganic P, and phosphate monoester was the major form of organic P present in TLC. The addition of inorganic P fertilizer increased the labile/moderately labile P, whereas the compost increased the moderately labile P extractable with weak acid (pH 4.2). Even though the amount of the labile P fraction in the compost-treated soil was smaller than that in the fertilizer-treated soils, ryegrass growth and plant P uptake were greater. The net transformation of the labile/moderately labile P was slower in the compost-treated soil without plant growth, however it was faster with plant growth. This study showed that P applied either as an inorganic or an organic amendment was recovered in different P fractions in a calcareous soil, and therefore it is expected that the P source would affect soil P chemistry. A weak acid extractable inorganic P fraction should be considered as plant available P especially in the compost-treated soil, that is converted into plant available P through direct and/or indirect root-induced acidification in the rhizosphere.

  19. Phosphorus retention in calcareous soils and the effect of organic matter on its mobility

    Directory of Open Access Journals (Sweden)

    von Wandruszka Ray

    2006-06-01

    Full Text Available Abstract A survey of the interactions between phosphorus (P species and the components of calcareous soils shows that both surface reactions and precipitation take place, especially in the presence of calcite and limestone. The principal products of these reactions are dicalcium phosphate and octacalcium phosphate, which may interconvert after formation. The role of calcium carbonate in P retention by calcareous soils is, however, significant only at relatively high P concentrations – non-carbonate clays play a more important part at lower concentrations. In the presence of iron oxide particles, occlusion of P frequently occurs in these bodies, especially with forms of the element that are pedogenic in origin. Progressive mineralization and immobilization, often biological in nature, are generally observed when P is added as a fertilizer. Manure serves both as a source of subsurface P and an effective mobilizing agent. Blockage of P sorption sites by organic acids, as well as complexation of exchangeable Al and Fe in the soil, are potential causes of this mobilization. Swine and chicken manure are especially rich P sources, largely due the practice of adding the element to the feed of nonruminants. Humic materials, both native and added, appear to increase recovery of Olsen P. In the presence of metal cations, strong complexes between inorganic P and humates are formed. The influence of humic soil amendments on P mobility warrants further investigation.

  20. 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)

  1. 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)

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

    Directory of Open Access Journals (Sweden)

    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.

  3. Effects of organic acids on cadmium and copper sorption and desorption by two calcareous soils.

    Science.gov (United States)

    Najafi, Sarvenaz; Jalali, Mohsen

    2015-09-01

    Low molecular weight organic acids (LMWOAs) present in soil alter equilibrium pH of soil, and consequently, affect heavy metal sorption and desorption on soil constitutes. This study was conducted to investigate the effects of different concentrations (0.1, 1, 2.5, 5, 10, 30, 40, 50, 70, and 100 mM) of citric, malic, and oxalic acids on sorption and desorption of cadmium (Cd) and copper (Cu) in two calcareous soils. Increasing the concentrations of three LMWOAs decreased the equilibrium pH of soil solutions. The results indicated that increase in organic acids concentrations generally reduced Cd and Cu sorption in soils. Increase concentrations of LMWOAs generally promoted Cd and Cu desorption from soils. A valley-like curve was observed for desorption of Cu after the citric acid concentration increment in soil 2. Increasing the concentrations of three LMWOAs caused a marked decrease in Kd(sorp) values of Cd and Cu in soils. In general, citric acid was the most effective organic acid in reducing sorption and increasing desorption of both metals, and oxalic acid had the minimal impact. The results indicated that LMWOAs had a greater impact on Cu sorption and desorption than Cd, which can be attributed to higher stability constants of organic acids complexes with Cu compared to Cd. It can be concluded that by selecting suitable type and concentration of LMWOAs, mobility, and hence, bioavailability of heavy metals can be changed. So, environmental implications concerning heavy metals mobility might be derived from these findings.

  4. [Effects of different tillage methods on phospholipid fatty acids and enzyme activities in calcareous cinnamon soil].

    Science.gov (United States)

    Pei, Xue-Xia; Dang, Jian-You; Zhang, Ding-Yi; Wang, Jiao-Ai; Zhang, Jing

    2014-08-01

    In order to study changes of physical and chemical characteristics and microbial activities in soil under different tillage methods, effects of four tillage methods, rotary tillage (RT), subsoil tillage (ST), conventional tillage (CT) with corn straw returned to soil, and rotary tillage with no corn straw returned to soil (CK), on phospholipid fatty acids (PLFA) characteristics and hydrolase enzymes activities in calcareous cinnamon soil were investigated. The results showed that soil hydrolase enzymes activities, nutrient contents, microbial diversity varied greatly with the different tillage methods. Returning corn straw to soil increased the kinds, amount of soil total PLFAs, bacteria PLFAs and actonomycetes PLFAs, while decreased the fungi PLFAs, indicating that fungi was more adaptable than bacteria to an infertile environment. ST and CT resulted in higher amounts of total PLFAs, which were 74.7% and 53.3% higher than that of CK, indicating they were more beneficial to the growth of plants. They could also improve soil physical and chemical properties, increase alk-phosphatase, protease and urease activities, which would provide a favorable soil condition for high and stable crop yields.

  5. Biochar and manure effects on net nitrogen mineralization and greenhouse gas emissions from calcareous soil under corn

    Science.gov (United States)

    Few multiyear field studies have examined the impacts of a one-time biochar application on net N mineralization and greenhouse gas emissions in an irrigated, calcareous soil; yet such applications are hypothesized as a means of sequestering atmospheric CO2 and improving soil quality. We fall-applie...

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

    Directory of Open Access Journals (Sweden)

    Narges Milani

    Full Text Available 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(PO42.2H2O and zinc ammonium phosphate (Zn(NH4PO4 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(OH2 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

  7. 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 same

  8. 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.

  9. Enhanced levels of nicotianamine promote iron accumulation and tolerance to calcareous soil in soybean.

    Science.gov (United States)

    Nozoye, Tomoko; Kim, Suyoen; Kakei, Yusuke; Takahashi, Michiko; Nakanishi, Hiromi; Nishizawa, Naoko K

    2014-01-01

    Iron (Fe) is an essential nutrient in both plants and humans. Fe deficiency on calcareous soil with low Fe availability is a major agricultural problem. Nicotianamine (NA) is one of the Fe chelator in plants, which is involved in metal translocation into seeds, and serves as an antihypertensive substance in humans. In this study, soybean plants overexpressing the barley NA synthase 1 (HvNAS1) gene driven by the constitutive CaMV 35S promoter were produced using Agrobacterium-mediated transformation. The transgenic soybean showed no growth defect and grew normally. The NA content of transgenic soybean seeds was up to four-fold greater than that of non-transgenic (NT) soybean seeds. The level of HvNAS1 expression was positively correlated with the amount of NA, and a high concentration of NA was maintained in the seeds in succeeding generations. The Fe concentration was approximately two-fold greater in transgenic soybean seeds than in NT soybean seeds. Furthermore, the transgenic soybeans showed tolerance to low Fe availability in calcareous soil. Our results suggested that increasing the NA content in soybean seeds by the overexpression of HvNAS1 offers potential benefits for both human health and agricultural productivity.

  10. Free Oxide Distribution in Poorly and Well Drained Soils Developed on Calcareous Alluvial Deposits

    Institute of Scientific and Technical Information of China (English)

    N. K. MOUSTAKAS; P. E. BAROUCHAS

    2003-01-01

    A study on the distribution of free iron and manganese oxides was conducted in soils developed on calcareous alluvial deposits under subhumid climatic conditions, in Western Greece. Soil samples from two well drained soils and from two poorly drained soils, classified as Alfisols, were collected and used in this study. After certification of soil homogeneity the acid ammonium oxalate and dithionite-citrate-bicarbonate methods were used to extract free iron and manganese oxides from the samples. Iron oxides extracted by the dithionite-citrate-bicarbonate method (Fed) were significantly higher than the iron oxides extracted by the ammonium oxalate method (Feo), indicating that a considerable fraction is present in crystalline forms,independent of drainage status. A confirmation of free iron oxides and fine clay was detected. The ratios Feo/Fed and (Fed-Feo)/total Fe (Fet) could not be used to distinguish the well drained soils from the poorly drained soils. Manganese movement in a soluble form is independent of the fine clay.

  11. REMEDIATION OF POLLUTED SOILS BY UTILIZING HYDROTHERMALLY TREATED CALCAREOUS FLY ASHES

    Institute of Scientific and Technical Information of China (English)

    A. Moutsatsou; V. Protonotarios

    2006-01-01

    This paper investigates a treated fly ash to act as a synthetic zeolite to remediate soils polluted with heavy metals and metalloids (As, Pb, Cu, Zn, Fe, Cd and Mn). Four types of such 'zeolites' were synthesized by hydrothermal treatment of a calcareous fly ash derived from Greek lignite-fired power plants: two with excess of sodium hydroxide in a a former mining site at Lavrion, Greece. Mobilization and transfer of metals to the retention agents was effected by using HCl aq 1M, with satisfactory results with respect to As, Pb, Cu, Mn and Cd. The great variety of metal complexes in soil was found to be of major importance for the effectiveness of the overall process. The final products were solidified either on their own, or by using additives such as lime and cement.

  12. Dynamics of atmospheric nitrogen deposition in a temperate calcareous forest soil.

    Science.gov (United States)

    Morier, Isabelle; Guenat, Claire; Siegwolf, Rolf; Védy, Jean-Claude; Schleppi, Patrick

    2008-01-01

    In temperate forest ecosystems, soil acts as a major sink for atmospheric N deposition. A (15)N labeling experiment in a hardwood forest on calcareous fluvisol was performed to study the processes involved. Low amounts of ammonium ((15)NH(4)(+)) or nitrate ((15)NO(3)(-)) were added to small plots. Soil samples were taken after periods ranging from 1 h to 1 yr. After 1 d, the litter layer retained approximately 28% of the (15)NH(4)(+) tracer and 19% of (15)NO(3)(-). The major fraction of deposited N went through the litter layer to reach the soil within the first hours following the tracer application. During the first day, a decrease in extractable (15)N in the soil was observed ((15)NH(4)(+): 50 to 5%; (15)NO(3)(-): 60 to 12%). During the same time, the amount of microbial (15)N remained almost constant and the (15)N immobilized in the soil (i.e., total (15)N recovered in the bulk soil minus extractable (15)N minus microbial (15)N) also decreased. Such results can therefore be understood as a net loss of (15)N from the soil. Such N loss is probably explained by NO(3)(-) leaching, which is enhanced by the well-developed soil structure. We presume that the N immobilization mainly occurs as an incorporation of deposited N into the soil organic matter. One year after the (15)N addition, recovery rates were similar and approximately three-quarters of the deposited N was recovered in the soil. We conclude that the processes relevant for the fate of atmospherically deposited N take place rapidly and that N recycling within the microbes-plants-soil organic matter (SOM) system prevents further losses in the long term.

  13. Phytoavailability of Copper, Zinc and Cadmium in Sewage Sludge-Amended Calcareous Soils

    Institute of Scientific and Technical Information of China (English)

    LI Qiong; GUO Xue-Yan; XU Xing-Hua; ZUO Yu-Bao; WEI Dong-Pu; MA Yi-Bing

    2012-01-01

    The toxicity of trace elements (TEs),such as copper (Cu),zinc (Zn),and cadmium (Cd),often restrict land application of sewage sludge (SS) and there was little information about soil-plant transfer of TEs in SS from field experiments in China.In this study pot and field experiments were carried out for 2 years to investigate the phytoavailability of TEs in calcareous soils amended with SS.The results of the pot experiment showed that the phytoavailability of Zn and Cu in the SS was equal to 53.4%-80.9% and 54.8%-91.1% of corresponding water-soluble metal salts,respectively.The results from the field experiment showed that the contents of total Zn,Cu,and Cd in the soils increased linearly with SS application rates.With increasing SS application rates,the contents of Zn and Cu in the wheat grains initially increased and then reached a plateau,while there was no significant change of Cd content in the maize grains.The bioconcentration factors of the metals in the grains of wheat and maize were found to be in the order of Zn > Cu > Cd,but for the straw the order was Cd > Cu > Zn.It was also found that wheat grains could accumulate more metals compared with maize grains.The results will be helpful in developing the critical loads of sewage sludge applied to calcareous soils.

  14. Movement of Phosphorus in a Calcareous Soil as Affected by Humic Acid

    Institute of Scientific and Technical Information of China (English)

    DU Zhen-Yu; WANG Qing-Hua; LIU Fang-Chun; MA Hai-Lin; MA Bing-Yao; S.S.MALHI

    2013-01-01

    When humic acid (HA) and phosphorus (P) fertilizer are simultaneously applied to soil,HA may affect the movement of P.A laboratory incubation experiment was conducted to quantify the effects of a commercial HA product co-applied with monocalcium phosphate (MCP) on the distance of P movement and the concentration of P in various forms at different distances from the P fertilizer application site in a calcareous soil from northern China.Fertilizer MCP (at a rate equivalent to 26.6 kg P ha-1) was applied alone or in combination with HA (at 254.8 kg HA ha-1) to the surface of soil packed in cylinders (150 mm high and 50 mm internal diameter),and then incubated at 320 g kg-1 moisture content for 7 and 28 d periods.Extraction and analysis of each 2 mm soil layer in columns showed that the addition of HA to MCP increased the distance of P movement and the concentrations of water-extractable P,acid-extractable P and Olsen P in soil.The addition of HA to MCP could enhance P availability by increasing the distance of P movement and the concentration of extractable P in soil surrounding the P fertilizer.

  15. Effect of Straw Amendment on Soil Zn Availability and Ageing of Exogenous Water-Soluble Zn Applied to Calcareous Soil

    Science.gov (United States)

    Chen, Yanlong; Cui, Juan; Tian, Xiaohong; Zhao, Aiqing; Li, Meng; Wang, Shaoxia; Li, Xiushaung; Jia, Zhou; Liu, Ke

    2017-01-01

    Organic matter plays a key role in availability and transformation of soil Zn (zinc), which greatly controls Zn concentrations in cereal grains and human Zn nutrition level. Accordingly, soils homogenized with the wheat straw (0, 12 g straw kg-1) and Zn fertilizer (0, 7 mg Zn kg-1) were buried and incubated in the field over 210 days to explore the response of soil Zn availability and the ageing of exogenous Zn to straw addition. Results indicated that adding straw alone scarcely affected soil DTPA-Zn concentration and Zn fractions because of the low Zn concentration of wheat straw and the high soil pH, and large clay and calcium carbonate contents. However, adding exogenous Zn plus straw increased the DTPA-Zn abundance by about 5-fold and had the similar results to adding exogenous Zn alone, corresponding to the increased Zn fraction loosely bounded to organic matter, which had a more dominant presence in Zn reaction than soil other constituents such as carbonate and minerals in calcareous soil. The higher relative amount of ineffective Zn (~50%) after water soluble Zn addition also occurred, and at the days of 120–165 and 180–210when the natural temperature and rainfall changed mildly, the ageing process of exogenous Zn over time was well evaluated by the diffusion equation, respectively. Consequently, combining crop residues with exogenous water soluble Zn application is promising strategy to maximize the availability of Zn in calcareous soil, but the higher ageing rate of Zn caused by the higher Zn mobility should be considered. PMID:28081179

  16. Effects of moisture and carbonate additions on CO2 emission from calcareous soil during closed-jar incubation

    Institute of Scientific and Technical Information of China (English)

    YanJie DONG; Miao CAI; JianBin ZHOU

    2014-01-01

    Calcareous soil contains organic and inorganic carbon (C) pools, which both contribute to CO2 emission during closed-jar incubation. The mineralization of organic C and dissolution of inorganic C are both related to soil moisture, but the exact effect of water content on CO2 emission from calcareous soil is unclear. The objective of this experiment was to determine the effect of soil water content (air-dried, 30%, 70%, and 100%water-holding capacity (WHC)), carbonate type (CaCO3 or MgCO3), and carbonate amount (0.0, 1.0%, and 2.0%) on CO2 emission from calcareous soil during closed-jar incubation. Soil CO2 emission increased significantly as the water content in-creased to 70%WHC, regardless of whether or not the soil was amended with carbonates. Soil CO2 emission re-mained the same or increased slowly as the soil water content increased from 70%WHC to 100%WHC. When the water content was≤30%WHC, soil CO2 emission from soil amended with 1.0%inorganic C was greater than that from unamended soil. When the soil water content was 70%or 100%WHC, CO2 emission from CaCO3 amended soil was greater than that from the control. Furthermore, CO2 emission from soil amended with 2.0%CaCO3 was greater than that from soil amended with 1.0%CaCO3. Soil CO2 emission was higher in the MgCO3 amended soil than from the unamended soil. Soil CO2 emission decreased as the MgCO3 content increased. Cumulative CO2 emission was 3-6 times higher from MgCO3 amended soil than from CaCO3 amended soil. There was significant interaction effect between soil moisture and carbonates on CO2 emission. Soil moisture plays an important role in CO2 emission from calcareous soil because it affects both biotic and abiotic processes during the closed-jar incu-bation.

  17. 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

  18. Time-Dependent Zinc Desorption in Some Calcareous Soils of Iran

    Institute of Scientific and Technical Information of China (English)

    M.BARANIMOTLAGH; M.GHOLAMI

    2013-01-01

    Desorption of zinc (Zn) from soil is an important factor governing Zn concentration in the soil solution and Zn availability to plants.Batch experiments were performed to study the kinetics of Zn desorption by diethylenetriaminepentaacetic acid (DTPA) from 15 calcareous soil samples taken from Golestan Province in northern Iran.Soils were equilibrated with 0.005 mol L-1 DTPA solutions for 0.25 to 192 h.The results showed that the extraction process consisted of rapid extraction in the first 2 h followed by much slower extraction for the remainder of the experiment.Desorption kinetic data was fitted to pseudo-first-order kinetic model.The experimental data were found to deviate from the straight line of the pseudo-first-order plots after 2 h.The model of two first-order reactions was fitted to the kinetic data and allowed to distinguish two pools for Zn:a labile fraction (Q1),quickly extracted with a rate constant k1,and a slowly labile fraction (Q2),more slowly extracted with a rate constant k2.The applicability of pseudo-second-order model in describing the kinetic data of Zn desorption was also evaluated.

  19. Phosphorus Changes and Sorption Characteristics in a Calcareous Soil Under Long-Term Fertilization

    Institute of Scientific and Technical Information of China (English)

    GUO Sheng-Li; DANG Ting-Hui; HAO Ming-De

    2008-01-01

    Knowledge of phosphorus (P) behavior in long-term fertilized soils is essential for programming fertilization practices and for sustaining environmental quality.The long-term (1984-1997) effects of various fertilization treatments on P changes and sorption isotherms as well as the relationship of soil properties to P sorption and P forms were evaluated in an Ustic Isohumisol,a calcareous soil,on the Loess Plateau,China.Compared to 1984,after 13 years of crop production,total soil P in the no-P treatments (control and N treatment) decreased by 5%-7%,but in the phosphorus fertilizer alone (P),nitrogen and phosphorus fertilizers in combination (NP),manure alone (M),and nitrogen and phosphorus fertilizers and manure in combination (NPM) treatments,it increased by 22%,19%,28%,and 58%,respectively.Residual fertilizer P was found mainly in NH4Ac-soluble P (Cas-P),followed by NaHCO3-sohible P (NaHCO3-P),and NH4F-soluble P (Al-P).Phosphorus sorption in the soils with different fertilization practices fit the Langmuir equations.Phosphorus sorption capacity in the no-P treatments increased,whereas it decreased in the P-included treatments (P,NP,and NPM treatments).Phosphorus sorption maximum (Qm) was significantly and negatively correlated to inorganic P including Na4CO3-P,Cas-P,NaOH-Na2CO3-soluble P (Fe-P),and AI-P (P ≤ 0.01).Moreover,long-term fertilization increased soil organic carbon in the NP,M,and NPM treatments and decreased pH in the NP and NPM treatments.Thus,the ability of the soil to release sorbed P to the environment increased under long-term P fertilization.

  20. 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

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

    Science.gov (United States)

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

    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 (70)Zn(2+); comparative extractions included 0.005 M DTPA, 0.43 M HNO3 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 Na2-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 CaCO3 was dissolved in F2 of the SEP, the DTPA dissolved only a very small proportion of the soil CaCO3. 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(NO3)2 (PCO2 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 ZnCO3. 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 log10 Ks (5.1) was 2.8 log units lower than that of the mineral smithsonite (ZnCO3).

  2. 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.

  3. 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.

  4. Response of Tomato on Calcareous Soils to Different Seedbed Phosphorus Application Rates

    Institute of Scientific and Technical Information of China (English)

    ZHANG Xiao-Sheng; LIAO Hong; CHEN Qing; P. CHRISTIE; LI Xiao-Lin; ZHANG Fu-Suo

    2007-01-01

    Field experiments were conducted with five rates (0, 75, 150, 225, and 450 kg P2O5 ha-1) of seedbed P fertilizer application to investigate the yield of tomato in response to fertilizer P rate on calcareous soils with widely different levels of Olsen P (13-142 mg kg-1) at 15 sites in some suburban counties of Beijing in 1999. Under the condition of no P fertilizer application, tomato yield generally increased with an increase in soil test P levels, and the agronomic level for soil testing P measured with Olsen method was 50 or 82 mg kg-1 soil to achieve 85% or 95% of maximum tomato yield, respectively. With regard to marketable yield, in the fields where Olsen-P levels were < 50 mg kg-1, noticeable responses to applied P were observed. On the basis of a linear plateau regression, the optimum seedbed P application rate in the P-insufficient fields was 125 kg P2O5 ha-1 or about 1.5-2 times the P removal from harvested tomato plants. In contrast, in fields with moderate (50 < Olsen P < 90 mg kg-1) or high (Olsen P > 90 mg kg-1) available P, there was no marked effect on tomato fruit yield. Field survey data indicated that in most fields with conventional P management, a P surplus typically occurred. Thus, once the soil test P level reached the optimum for crop yield, it was recommended that P fertilizer application be restricted or eliminated to minimize negative environmental effects.

  5. Soil formation on reddish-brown calcareous till under herbaceous vegetation during forty years

    Directory of Open Access Journals (Sweden)

    Reintam, Loit

    2007-06-01

    Full Text Available A special experiment was established in 1963 and initiated in 1964 at Eerika, Tartu County, Estonia (58°22¢ N, 26°36¢ E to study pedogenesis and its continuous development under grass-herbaceous vegetation on reddish-brown calcareous till which was practically free from organic carbon (0.6 g kg–1 and nitrogen (0.2 g kg–1. The results of the study of three earlier decades have been discussed earlier. This paper deals with the processes of synchronous production and soil formation as well as with pedogenetic activity during the fourth decade of the experiment and during the total period of 40 years. An intensive humus-accumulative process, wavy and cyclic in intensity, has continued, accompanied by the breakdown of skeletal carbonates, partial leaching of products, formation and accumulation of amorphous and crystalline nonsiliceous products of weathering, progress of argillization in situ, and slight lessivage of fine silt and clay within the thin top of enriched humus solum. Net accumulation of organic carbon and nitrogen was obtained by nearly equivalent amounts of humifiable issues of the production process. As these are temporally dynamic, the temporal periodicity of mineralization and humification relationships is also characteristic of synchronous pedogenesis. The low C : N ratio indicates an excellent quality of the humus formed since the beginning of primary soil formation. Against the background of the decadewise dynamic fulvicity of the humus and evident decrease in its total solubility, the transformation of Ca-humates into humins and the formation of R2O3-humic-fulvic complexes at the expense of RO-humic-fulvic complexes already during the third decade were ascertained. Intensification of the bonds of the humic-fulvic complexes with inactive sesquioxides and clay minerals and decrease in the amount of fulvic acids in the interlayeral structure of clay progressed during the fourth decade. Due to the weathering of sand fractions

  6. Effects of Common Ions on Zn Sorption in Some Calcareous Soils of Western Iran

    Institute of Scientific and Technical Information of China (English)

    M. JALALI; N. AHMADI MOHAMMAD ZINLI

    2012-01-01

    Zinc (Zn) is essential to plant growth and relatively mobile in soils.This study was conducted to assess the effect of common ions (Ca2+,K+,Na+,NH4+,Cl-,NO3-,and H2PO4-) on sorption of Zn in surface samples of ten calcareous soils from western Iran using 10 mmol L-1 KCl,KNO3,KH2PO4,Ca(NO3)2,NaNO3,and NH4NO3 solutions as background electrolytes.The results indicated that both NH4+,K+,and Ca2+ equally decreased Zn sorption as compared to Na+.Zinc sorption was decreased by H2PO4- as compared to NO3- and Cl-.The Langmuir and Freundlich equations fitted closely to the sorption data of all ions.The Langmuir maximum,bonding energy constant,and Freundlich distribution coefficient for Zn sorption differed among the various ionic background electrolytes.Langmuir sorption parameters showed that the presence of H2PO4- decreased the maximum Zn adsorbed,but increased the bonding energy.Although K+ and NH4+ equally influenced maximum Zn adsorbed,they differed in their effect on the distribution coefficient of Zn in soils.Values of saturation index calculated using Visual MINTEQ indicated that at the low Zn concentration,Zn solubility was controlled by sorption reactions and at the high Zn concentration,it was mainly controlled by sorption and mineral precipitation reactions,such as precipitation of Zn3 (PO4)2·4H2O,Zn5(OH)6(CO3)2,and ZnCO3.For most ionic background electrolytes,soil pH,CaCO3,and cation exchange capacity (CEC) were significantly correlated with sorption parameters.

  7. [Effects of long-term fertilization on pH buffer system of sandy loam calcareous fluvor-aquic soil].

    Science.gov (United States)

    Wang, Ji-Dong; Qi, Bing-Jie; Zhang, Yong-Chun; Zhang, Ai-Jun; Ning, Yun-Wang; Xu, Xian-Ju; Zhang, Hui; Ma, Hong-Bo

    2012-04-01

    Soil samples (0-80 cm) were collected from a 30-year fertilization experimental site in Xuzhou, Jiangsu Province of East China to study the variations of the pH, calcium carbonate and active calcium carbonate contents, and pH buffer capacity of sandy loam calcareous fluvor-aquic soil under different fertilization treatments. Thirty-year continuous application of different fertilizers accelerated the acidification of topsoil (0-20 cm), with the soil pH decreased by 0.41-0.70. Under different fertilization, the soil pH buffer capacity (pHBC) varied from 15.82 to 21.96 cmol x kg(-1). As compared with no fertilization, single N fertilization decreased the pHBC significantly, but N fertilization combined with organic fertilization could significantly increase the pHBC. The soil pHBC had significant positive correlations with soil calcium carbonate and active calcium carbonate contents, but less correlation with soil organic matter content and soil cation exchange capacity, suggesting that after a long-term fertilization, the sandy loam calcareous fluvor-aquic soil was still of an elementary calcium carbonate buffer system, and soil organic matter and cation exchange capacity contributed little to the buffer system. The soil calcium carbonate and active calcium carbonate contents were greater in 0-40 cm than in 40-80 cm soil layer. Comparing with soil calcium carbonate, soil active calcium carbonate was more sensitive to reflect the changes of soil physical and chemical properties, suggesting that the calcium carbonate buffer system could be further classified as soil active calcium carbonate buffer system.

  8. 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.

  9. Phytoavailability and fractions of iron and manganese in calcareous soil amended with composted urban wastes.

    Science.gov (United States)

    Gallardo-Lara, Francisco; Azcón, Mariano; Polo, Alfredo

    2006-01-01

    Little is known about the effects of applying composted urban wastes on the phytoavailability and distribution of iron (Fe) and manganese (Mn) among chemical fractions in soil. In order to study this concern several experiments in pots containing calcareous soil were carried out. The received treatments by adding separately two rates (20 and 80 Mg ha-1) of municipal solid waste (MSW) compost and/or municipal solid waste and sewage sludge (MSW-SS) co-compost. The cropping sequence was a lettuce crop followed by a barley crop. It was observed that treatments amended with composted urban wastes tended to promote slight increases in lettuce yield compared to the control. The highest Fe levels in lettuce were found when higher rates of MSW-SS co-compost were applied; these values were significant compared to those obtained in the other treatments. In all cases, the application of organic materials increased the concentration and uptake of Mn in lettuce compared to the control; however, these increases were significant only when higher rates of MSW compost were applied. The organic amendments had beneficial delayed effects on barley yields, showing, in most cases, significant increases compared to the control. In this context, treatments with MSW compost were found to be more effective than the equivalent treatments amended with MSW-SS co-compost. Compared to the control, composted urban wastes increased Fe concentration in straw and rachis, and decreased Fe concentration in barley grain. Similarly, a decreased concentration of Mn in the dry matter of barley crop grown in soils treated with composted urban wastes was observed.

  10. 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

  11. 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.

  12. CaCO3 and SrCO3 bioprecipitation by fungi isolated from calcareous soil.

    Science.gov (United States)

    Li, Qianwei; Csetenyi, Laszlo; Paton, Graeme Iain; Gadd, Geoffrey Michael

    2015-08-01

    The urease-positive fungi Pestalotiopsis sp. and Myrothecium gramineum, isolated from calcareous soil, were examined for their properties of CaCO3 and SrCO3 biomineralization. After incubation in media amended with urea and CaCl2 and/or SrCl2 , calcite (CaCO3 ), strontianite (SrCO3 ), vaterite in different forms [CaCO3 , (Cax Sr1-x )CO3 ] and olekminskite [Sr(Sr,Ca)(CO3 )2 ] were precipitated, and fungal 'footprints' were observed on mineral surfaces. The amorphous precipitate mediated by Pestalotiopsis sp. grown with urea and equivalent concentrations of CaCl2 and SrCl2 was identified as hydrated Ca and Sr carbonates by Fourier transform infrared spectroscopy. Liquid media experiments showed M. gramineum possessed the highest Sr(2+) removal ability, and ∼ 49% of supplied Sr(2+) was removed from solution when grown in media amended with urea and 50 mM SrCl2 . Furthermore, this organism could also precipitate 56% of the available Ca(2+) and 28% of the Sr(2+) in the form of CaCO3 , SrCO3 and (Cax Sr1-x )CO3 when incubated in urea-amended media and equivalent CaCl2 and SrCl2 concentrations. This is the first report of biomineralization of olekminskite and coprecipitation of Sr into vaterite mediated by fungi. These findings suggest that urease-positive fungi could play an important role in the environmental fate, bioremediation or biorecovery of Sr or other metals and radionuclides that form insoluble carbonates.

  13. OsIRO2 is responsible for iron utilization in rice and improves growth and yield in calcareous soil.

    Science.gov (United States)

    Ogo, Yuko; Itai, Reiko N; Kobayashi, Takanori; Aung, May Sann; Nakanishi, Hiromi; Nishizawa, Naoko K

    2011-04-01

    Iron (Fe) deficiency, a worldwide agricultural problem on calcareous soil with low Fe availability, is also a major human nutritional deficit. Plants induce Fe acquisition systems under conditions of low Fe availability. Previously, we reported that an Fe-deficiency-inducible basic helix-loop-helix (bHLH) transcription factor, OsIRO2, is responsible for regulation of the genes involved in Fe homeostasis in rice. Using promoter-GUS transformants, we showed that OsIRO2 is expressed throughout a plant's lifetime in a spatially and temporally similar manner to the genes OsNAS1, OsNAS2 and TOM1, which is involved in Fe absorption and translocation. During germination, OsIRO2 expression was detected in embryos. OsIRO2 expression in vegetative tissues was restricted almost exclusively to vascular bundles of roots and leaves, and to the root exodermis under Fe-sufficient conditions, and expanded to all tissues of roots and leaves in response to Fe deficiency. OsIRO2 expression was also detected in flowers and developing seeds. Plants overexpressing OsIRO2 grew better, and OsIRO2-repressed plants showed poor growth compared to non-transformant rice after germination. OsIRO2 overexpression also resulted in improved tolerance to low Fe availability in calcareous soil. In addition to increased Fe content in shoots, the overexpression plants accumulated higher amounts of Fe in seeds than non-transformants when grown on calcareous soil. These results suggest that OsIRO2 is synchronously expressed with genes involved in Fe homeostasis, and performs a crucial function in regulation not only of Fe uptake from soil but also Fe transport during germination and Fe translocation to grain during seed maturation.

  14. 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.

  15. Optimizing available phosphorus in calcareous soils fertilized with diammonium phosphate and phosphoric acid using Freundlich adsorption isotherm.

    Science.gov (United States)

    Naeem, Asif; Akhtar, Muhammad; Ahmad, Waqar

    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.

  16. Evaluation of chemical indices of soil Pb availability in calcareous soils

    Energy Technology Data Exchange (ETDEWEB)

    Al-Afifi, M.A. [Dept. of Plant Production, Coll. of Agricultural Science, United Arab Emirates Univ., Al Ain (United Arab Emirates)

    1994-12-31

    The objective of this study was to compure six soil test (1 M KNO{sub 3}, 1 M NH{sub 4}OAC, 0.005 M DTPA, 0.1 M EDTA, 1 M HNO{sub 3} and 0.025 M Ca DTPA B{sub 4}O{sub 7}) as extractants for soil Pb and as predictors of plant available Pb for wheat (Triticum aestivum L.) in the greenhouse. The soils received 0, 200 and 400 mg Pb kg{sup -1} as Pb(NO{sub 3}){sub 2} and are referred to as Pb{sub 0}, Pb{sub 1} and Pb{sub 2} treatments respectively. Of the six soil extractants, 1 M HNO{sub 3} was the most effective extractant for Pb from Pb{sub 0} treatment whereas 0.1 M EDTA and 0.025 M Ca DTPA-B{sub 4}O{sub 7} were the best and equally effective in their ability to extract Pb from Pb{sub 1} and Pb{sub 2} treatments. Regression analysis was used to develop two variable models for predicting Pb uptake by wheat as a function of extractable Pb and selected soil properties. The 0.025 M Ca DTPA-B{sub 4}O{sub 7} extractant was the best in predicting uptake by wheat in Pb{sub 0} (r=0.791*** significant at p=0.001) and Pb{sub 1} (r=0.726***) and Pb{sub 2} (r=0.942***) treatments. (orig.) [Deutsch] Ziel der Untersuchung war der Vergleich von 6 Methoden (a) 1 M KNO{sub 3}, (b) 1 M NH{sub 4} OAC, (c) 0.25 M Ca DTPA-B{sub 4}O{sub 7}, (d) 0.005 M DTPA, (e) 0.1 M EDTA, (f) 1 M HNO{sub 3} zur Charakterisierung des fuer Pflanzen verfuegbaren Boden-Pb. Proben (0-15 cm) von 22 kalkhaltigen Boeden wurden mit 0 (=Pb{sub 0}), 200 (=Pb{sub 1}), bzw. 400 (=Pb{sub 2}) mg Pb kg{sup -1} als Pb (NO{sub 3}){sub 2} versetzt und im Gefaessversuch mit Weizen kultiviert. Methode (f) extrahierte am meisten aus Pb{sub 0}, (c) und (e) brachten mehr aus Pb{sub 1} und Pb{sub 2}, (c) korrelierte am besten mit dem Pflanzenentzug (Pb{sub 0} r=0,791*** bei p=0.001; Pb{sub 1} 0.726***, Pb{sub 2} 0.942***). (orig.)

  17. 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

  18. 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.

  19. Soil pH management by calcareous and siliceous minerals: effect on N2O yield in nitrification and denitrification

    Science.gov (United States)

    Nadeem, Shahid; Bakken, Lars; Dörsch, Peter

    2016-04-01

    Amelioration of soil pH by liming is necessary and common practice in vast areas of crop production. It is well known that pH is one of the most pervasive factors controlling rates and product stoichiometries in microbially mediated N transformations, including N2O emissions. While liming of acid soils appears to increase N2O reductase activity in denitrification (resulting in less N2O relative to N2), sudden pH raise may boost nitrification and hence N2O emission from ammonia oxidation. Thus, the net effect of liming on N2O emissions is not straightforward, which probably explains why soil pH management has not been embraced as a strategy for mitigating N2O emissions so far. Here we report laboratory incubations in which we determined potential rates and N2O yields in soils from an ongoing field experiment, comparing traditional calcareous limes (calcite, dolomite) with mafic minerals (olivine, different types of plagioclase). The experiment is in its second year, and shows strong pH increase (0.7-1.5, units) in plots with calcareous limes, a weak pH increase (~ 0.2 unit) in the olivine treatment and no measurable pH increase with the plagioclases. Potential nitrification rates correlated positively with effective soil pH as did the N2O yield, measured as N2O accumulation rate over NO2- + NO3- accumulation rate. The N2O yield increased in the order, control automated field flux robot (using fast box technique) in the same liming experiment.

  20. 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.

  1. Assessing the Mobility of Lead, Copper and Cadmium in a Calcareous Soil of Port-au-Prince, Haiti

    Directory of Open Access Journals (Sweden)

    Urbain Fifi

    2013-11-01

    Full Text Available The presence of heavy metals in the environment constitutes a potential source of both soil and groundwater pollution. This study has focused on the reactivity of lead (Pb, copper (Cu and Cadmium (Cd during their transfer in a calcareous soil of Port-au-Prince (Haiti. Kinetic, monometal and competitive batch tests were carried out at pH 6.0. Two simplified models including pseudo-first-order and pseudo-second-order were used to fit the experimental data from kinetics adsorption batch tests. A good fit of these data was found with pseudo-second-order kinetic model which indicates the applicability of this model to describe the adsorption rates of these metals on the soil. Monometal batch tests indicated that both Langmuir and Freundlich models allowed a good fit for experimental data. On the basis of the maximum adsorption capacity (qmax, the order affinity of Pb, Cu and Cd for the studied soil was Pb2+ > Cu2+ > Cd2+. Competitive sorption has proved that the competition between two or several cations on soils for the same active sites can decrease their qmax. These results show that, at high metal concentrations, Cd may pose more threat in soils and groundwater of Port-au-Prince than Pb and Cu.

  2. Effect of Long-Term Fertilization on Organic Nitrogen Forms in a Calcareous Alluvial Soil on the North China Plain

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    In order to illustrate the change of nitrogen (N) supply capacity after long-term application of manure and chemical fertilizer, as well as to properly manage soil fertility through fertilizer application under the soil-climatic conditions of the North China Plain, organic N forms were quantified in the topsoil with different manure and chemical fertilizer treatments in a 15-year fertilizer experiment in a Chinese calcareous alluvial soil Soil total N (TN) and various organic N forms were significantly influenced by long-term application of chemical fertilizer and manure. TN, total hydrolysable N, acid-insoluble N, amino acid N and ammonium N in the soil increased significantly (P < 0.05) with increasing manure and fertilizer N rates, but were not influenced by increasing P rates. Also, application of manure or N fertilizer or P fertilizer did not significantly influence either the quantity of amino sugar N or its proportion of TN. Application of manure significantly increased (P < 0.05) hydrolysable unknown N, but adding N or P did not. In addition, application of manure or N fertilizer or P fertilizer did not significantly influence the proportions of different soil organic N forms.

  3. Assessing the mobility of lead, copper and cadmium in a calcareous soil of Port-au-Prince, Haiti.

    Science.gov (United States)

    Fifi, Urbain; Winiarski, Thierry; Emmanuel, Evens

    2013-11-01

    The presence of heavy metals in the environment constitutes a potential source of both soil and groundwater pollution. This study has focused on the reactivity of lead (Pb), copper (Cu) and Cadmium (Cd) during their transfer in a calcareous soil of Port-au-Prince (Haiti). Kinetic, monometal and competitive batch tests were carried out at pH 6.0. Two simplified models including pseudo-first-order and pseudo-second-order were used to fit the experimental data from kinetics adsorption batch tests. A good fit of these data was found with pseudo-second-order kinetic model which indicates the applicability of this model to describe the adsorption rates of these metals on the soil. Monometal batch tests indicated that both Langmuir and Freundlich models allowed a good fit for experimental data. On the basis of the maximum adsorption capacity (qmax), the order affinity of Pb, Cu and Cd for the studied soil was Pb2+ > Cu2+ > Cd2+. Competitive sorption has proved that the competition between two or several cations on soils for the same active sites can decrease their qmax. These results show that, at high metal concentrations, Cd may pose more threat in soils and groundwater of Port-au-Prince than Pb and Cu.

  4. Assessing the Mobility of Lead, Copper and Cadmium in a Calcareous Soil of Port-au-Prince, Haiti †

    Science.gov (United States)

    Fifi, Urbain; Winiarski, Thierry; Emmanuel, Evens

    2013-01-01

    The presence of heavy metals in the environment constitutes a potential source of both soil and groundwater pollution. This study has focused on the reactivity of lead (Pb), copper (Cu) and Cadmium (Cd) during their transfer in a calcareous soil of Port-au-Prince (Haiti). Kinetic, monometal and competitive batch tests were carried out at pH 6.0. Two simplified models including pseudo-first-order and pseudo-second-order were used to fit the experimental data from kinetics adsorption batch tests. A good fit of these data was found with pseudo-second-order kinetic model which indicates the applicability of this model to describe the adsorption rates of these metals on the soil. Monometal batch tests indicated that both Langmuir and Freundlich models allowed a good fit for experimental data. On the basis of the maximum adsorption capacity (qmax), the order affinity of Pb, Cu and Cd for the studied soil was Pb2+ > Cu2+ > Cd2+. Competitive sorption has proved that the competition between two or several cations on soils for the same active sites can decrease their qmax. These results show that, at high metal concentrations, Cd may pose more threat in soils and groundwater of Port-au-Prince than Pb and Cu. PMID:24192791

  5. Effects of organic amendments and irrigation waters on the physical and chemical properties of two calcareous soils in Bahrain.

    Science.gov (United States)

    Raveendran, E; Grieve, I C; Madany, I M

    1994-04-01

    The present investigation studies the effects of cow and chicken manure and sewage sludge at different rates of addition and with two irrigation waters of different salinities on two major calcareous soils in Bahrain. The aim was to quantify potential improvements in soil quality, the accumulation of trace metals, and quality of leachates.From the pot experiments it was found that soil waterholding capacity did not change significantly after addition of organic amendments, except in the case of sewage sludge. Total organic carbon and total Kjeldhal nitrogen content increased in the 0-5 cm layer. Low salinity water and sewage applications improved aggregate stability. Extractable phosphorus was enhanced by the chicken manure treatment more than others. Addition of different organic amendments did not affect exchangeable cations. pH values did not show appreciable changes and soils were neutral. Trace metals studied were present at non-toxic levels in the 0-5 cm layer. Zinc and copper were the only metal showing a tendency to leach to the lower soil layer. In all cases metal levels in the surface layer were proportional to the quantities added in the amendments and their levels in the leachate were very low.

  6. 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...

  7. CO2 efflux from a calcareous Mojave Desert soil: isotopic results from a laboratory and field study

    Science.gov (United States)

    Verburg, P.; Stevenson, B.

    2011-12-01

    Soil inorganic carbon (SIC) represents a substantial C pool in arid ecosystems. The contribution of the SIC pool to net ecosystem C flux is poorly understood but has gained attention because there have been reports of anomalous C fluxes in some arid environments. In the context of climate change, altered precipitation patterns and changes in soil pCO2 values (from changes in vegetation density, plant water use efficiency, and belowground respiration) could potentially affect SIC storage in some ecosystems. The stable carbon isotope values of organic and inorganic carbon (e.g. carbonates) can differ substantially and may be useful in determining whether PIC influences C fluxes. However, variable rates of heterotrophic and root respiration and diffusion of atmospheric CO2 into the soil as well as the variation and complexity of the CaCO3-CO2-H2O system at different soil depths can complicate interpretation of isotopic data. We monitored soil CO2 concentrations and CO2 efflux from irrigated and non-irrigated plots in a calcareous soil at the Mojave Global Change Facility (MGCF). The site is on the northern part of the Mojave Desert with a mean annual precipitation of 71 mm and vegetation characterized by a Larrea tridentata, Lycium spp., Ambrosia dumosa plant community. We used a Keeling plot approach to determine source δ13C values from effluxed CO2-13C in a laboratory incubation experiment and from direct field measurements of soil CO2-13C. Data from the laboratory incubation experiment suggested that there was a contribution of PIC on effluxed CO2-13C in a closed system, but results from the field measurements were much more difficult to interpret and did not support a large contribution of SIC to CO2 fluxes in these soils. We discuss the usefulness of isotopic measure of CO2 on CO2 efflux in the context of the MGCF experiment.

  8. 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.

  9. Sorption, desorption, and speciation of Cd, Ni, and Fe by four calcareous soils as affected by pH.

    Science.gov (United States)

    Tahervand, Samaneh; Jalali, Mohsen

    2016-06-01

    The sorption, desorption, and speciation of cadmium (Cd), nickel (Ni), and iron (Fe) in four calcareous soils were investigated at the pH range of 2-9. The results indicated that sorption of Fe by four soils was higher than 80 % at pH 2, while in the case of Cd and Ni was less than 30 %. The most common sequence of metal sorption at pH 2-9 for four soils was in the order of Fe ≫ Ni > Cd. Cadmium and Ni sorption as a function of pH showed the predictable trend of increasing metal sorption with increase in equilibrium pH, while the Fe sorption trend was different and characterized by three phases. With regard to the order of Cd, Ni, and Fe sorption on soils, Cd and Ni showed high affinity for organic matter (OM), whereas Fe had high tendency for calcium carbonate (CaCO3). Results of metal desorption using 0.01 M NaCl demonstrated that metal sorption on soils containing high amounts of CaCO3 was less reversible in comparison to soils containing high OM. In general, Cd and Ni desorption curves were characterized by three phases; (1) the greatest desorption at pH 2, (2) the low desorption at pH 3-7, and (3) the least desorption at pH > 7. The MINTEQ speciation solubility program showed that the percentage of free metals declined markedly with increase of pH, while the percentage of carbonate and hydroxyl species increased. Furthermore, MINTEQ predicted that saturation index (SI) of metals increased with increasing pH.

  10. 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.

  11. 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.

  12. Vesicular Arbuscular Mycorrhizae—Mediated Uptake and Translocation of P and Zn by Wheat in Calcareous Soil

    Institute of Scientific and Technical Information of China (English)

    TUSHIHUA; T.B.GOH; 等

    1997-01-01

    Vesicular-arbuscular mycorrhizal(VMA) fungi have been credited with improving the growth and mineral nutritons of many host plants but these effects are moderated by soil factors and nutrient balance.The combined effects of VAM,Zn and P application on the growth and translocation of nutrients in wheat were investigated using a calcareous soil marginal in P and Zn concentrations.Wheat was grown in a growth chamber under various combinations of VAM,P and Zn with measurements done at heading stage and maturity,Vegetative dry matter accumlation was increased by P application and reduced by VAM treatments.Both P and VAM increased grain yield.Zince oncentration and uptake were generally reduced by P addition and VAM infection,There were no antagonistic effects of Zn on P acquisition in the plant,The role of VAM in enhancing the translocation of Zn and P from root to grain would be beneficial to seed setting and yield.

  13. Pyrite and pyritic mill tailing as a source of iron in a calcareous iron-deficient soil

    Energy Technology Data Exchange (ETDEWEB)

    Barrau, E.M.; Berg, W.A.

    1977-01-01

    Mill wastes from ore processing, particularly acid-forming pyrites, often pose disposal problems. This greenhouse study evaluated pyrite and a pyritic mill tailing as Fe sources on an Fe-deficient calcareous soil. Pyrite and tailing <0.1 mm in diameter were applied at rates of 45 and 135 metric ton/ha. Controls, 200 and 600 ppM Fe as Fe/sub 2/(SO/sub 4/)/sub 3/ and 5 and 15 ppM Fe as FeEDDHA, were used as standards. The treatments were seeded with sudangrass (Sorghum vulgare sudanense) and six successive crops were harvested. Sudangrass yields increased 160 to 200% with pyrite and tailing treatments; these yields were significantly greater than the control and were comparable to yields from the other Fe sources. The 5 ppM FeEDDHA treatment, however, increased yield for only the first two crops. Plant-available soil Fe measured by DTPA extraction increased with all Fe treatments, while the levels of DTPA-extractable Zn and Mn remained the same or increased slightly. DTPA-extractable Cu doubled with the high rate of pyrite addition. The concentration of Fe in the plants remained the same or increased slightly with the Fe treatments, while concentrations of Zn, Cu, and Mn all decreased.

  14. Field application of mycorrhizal bio-inoculants affects the mineral uptake of a forage legume (Hedysarum coronarium L.) on a highly calcareous soil.

    Science.gov (United States)

    Labidi, S; Jeddi, F Ben; Tisserant, B; Yousfi, M; Sanaa, M; Dalpé, Y; Sahraoui, A Lounès-Hadj

    2015-05-01

    The efficiency of two mycorrhizal bio-inoculants on the mineral uptake during the growth stages of a Mediterranean forage legume sulla (Hedysarum coronarium L.) was studied in the field on a highly calcareous soil. The first inoculum (Mm) was made up of a mixture of native arbuscular mycorrhizal fungi (AMF) isolated from calcareous soils: Septoglomus constrictum, Funneliformis geosporum, Glomus fuegianum, Rhizophagus irregularis and Glomus sp. The second was a commercial inoculum (Mi) containing one AMF species: R. irregularis. Both mycorrhizal inoculants increased total and arbuscular colonization of sulla roots. Inoculation with Mm showed a positive effect on sulla shoot dry weight (SDW) when compared to Mi and non-inoculated plants (control). Mineral contents (P, Mg, Mn, Fe) were higher in the shoots of sulla plants cultivated on mycorrhiza-inoculated plots compared to non-inoculated ones. This enhancement was observed during the flowering stage for P, Mg and Mn and during the rosette stage for Fe. An increase in P content of 50 % in plants inoculated with Mm compared to non-inoculated ones may be explained by the induction of root alkaline and acid phosphatase activities. Higher efficiency of native AMF species adapted to calcareous soils opens the way towards the development of mycorrhiza bio-fertilizers targeted to improve sustainable fertilization management in such soils.

  15. 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.

  16. Influence of sugarcane bagasse-derived biochar application on nitrate leaching in calcaric dark red soil.

    Science.gov (United States)

    Kameyama, K; Miyamoto, T; Shiono, T; Shinogi, Y

    2012-01-01

    Application of biochar has been suggested to improve water- and fertilizer-retaining capacity of agricultural soil. The objective of this study was to evaluate the effects of bagasse charcoal (sugarcane [ L.] bagasse-derived biochar) on nitrate (NO) leaching from Shimajiri Maji soil, which has low water- and fertilizer-retaining capacity. The nitrate adsorption properties of bagasse charcoal formed at five pyrolysis temperatures (400-800° C) were investigated to select the most suitable bagasse charcoal for NO adsorption. Nitrate was able to adsorb onto the bagasse charcoal formed at pyrolysis temperatures of 700 to 800° C. Nitrate adsorption by bagasse charcoal (formed at 800° C) that passed through a 2-mm sieve was in a state of nonequilibrium even at 20 h after the addition of 20 mg N L KNO solution. Measurements suggested that the saturated and unsaturated hydraulic conductivity of bagasse charcoal (800° C)-amended soils are affected by changes in soil tortuosity and porosity and the presence of meso- and micropores in the bagasse charcoal, which did not contribute to soil water transfer. In NO leaching studies using bagasse charcoal (800° C)-amended soils with different charcoal contents (0-10% [w/w]), the maximum concentration of NO in effluents from bagasse charcoal-amended soil columns was approximately 5% less than that from a nonamended soil column because of NO adsorption by bagasse charcoal (800° C). We conclude that application of bagasse charcoal (800°C) to the soil will increase the residence time of NO in the root zone of crops and provide greater opportunity for crops to absorb NO.

  17. 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

  18. 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.

  19. Bentonite and anthracite in alginate-based controlled release formulations to reduce leaching of chloridazon and metribuzin in a calcareous soil.

    Science.gov (United States)

    Flores Céspedes, F; Pérez García, S; Villafranca Sánchez, M; Fernández Pérez, M

    2013-08-01

    The leaching of herbicides through soil can be minimized using controlled release formulations (CRFs). In this research, bentonite and anthracite have been used as modifying agents in alginate-based CRFs prepared with chloridazon and metribuzin. These CRFs have been evaluated in a calcareous soil. The Kf and Koc values obtained from sorption experiments in soil have demonstrated a high leaching potential for both herbicides, mainly for metribuzin. Release kinetics in soil have showed that the control of release rate of chloridazon and metribuzin was possible by using bentonite and anthracite in CRFs, being this effect greater when we use anthracite as modifying sorbent. Using an empirical equation, the time taken for 50% of the active ingredient to be released (T50(soil)) was calculated. T50 values ranged between 2.88 d for metribuzin-bentonite alginate-based granules and 14.37 d for chloridazon-anthracite alginate-based granules, being the release rate higher in metribuzin CRFs than in those prepared with chloridazon, which has lower water solubility. Besides, a linear correlation between T50 values in water and soil was obtained. Mobility experiments carried out in a calcareous soil have shown that the use of CRFs reduces the presence of herbicides in the leachate compared to technical products, mainly for chloridazon. We found that one could design a right profile in the release rate of active ingredients from CRFs in each agro-environmental situation, and thus prevent the environmental pollution derived from the use of chloridazon and metribuzin.

  20. 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.

  1. Reclamation of highly calcareous saline-sodic soil using low quality water and phosphogypsum

    Science.gov (United States)

    Gharaibeh, M. A.; Rusan, M. J.; Eltaif, N. I.; Shunnar, O. F.

    2014-09-01

    The efficiency of two amendments in reclaiming saline sodic soil using moderately saline (EC) and moderate sodium adsorption ratio (SAR) canal water was investigated. Phosphogypsum (PG) and reagent grade calcium chloride were applied to packed sandy loam soil columns and leached with canal water (SAR = 4, and EC = 2.16 dS m-1). Phosphogypsum was mixed with top soil prior to leaching at application rates of 5, 10, 15, 20, 25, 35, 40 Mg ha-1, whereas calcium chloride was dissolved directly in water at equivalent rates of 4.25, 8.5, 12.75, 17.0, 21.25, 29.75, and 34 Mg ha-1, respectively. Both amendments efficiently reduced soil salinity and sodicity. Calcium chloride removed 90 % of the total Na and soluble salts whereas PG removed 79 and 60 %, respectively. Exchangeable sodium percentage was reduced by 90 % in both amendments. Results indicated that during cation exchange reactions most of the sodium was removed when effluent SAR was at maximum. Phosphogypsum has lower total costs than calcium chloride and as an efficient amendment an application of 30 Mg ha-1 and leaching with 4 pore volume (PV) of canal water could be recommended to reclaim the studied soil.

  2. Losses of Urea—Nitrogen Applied to Maize Grown on a Calcareous Fluvo—Aquic Soil in North China Plain

    Institute of Scientific and Technical Information of China (English)

    ZHANGSHAO-LIN; ZHUZHAO-LIANG; 等

    1992-01-01

    Field experiments were conducted in a maize (Zea mays L.)field of a calcareous fluvo-aquic soil in North China Plain for studying the fate and ammonia loss of urea-N applied at seedling stage,as well as the effectiveness of coated calcium carbide(CCC) in reducing N loss and in improving the yield efficiency of urea.Results show that:(1) For the surface-broadcast treatment ammonia volatilization (measured with micro-meteorological technique)took place quickly,reached the peak 20-26hr after application,and then declined gradually;the cumulative ammonia loss approached the maximum 188hr after application (30% of the N applied),and increased only to 32% 284 hr after application;the latter accounted for 71% of the total loss (45% of applied N).(2) In the case of point placement at a depth of 5-10 cm,ammonia loss 188hr after application was only 12% of the N applied,accounting for 40% of the total loss.(3) There was no difference in total loss between the application depths of 6cm and 10 cm,the loss of them was 30% and 29%,respectively.(4) Total loss of N applied at lower rate (40kg N/ha)with point deep placement at 6cm depth was found only 4% of the N applied,it rose up to 30% when the rate of application increased to 80kg N/ ha.(5) The nitrification inhibitor,CCC,seemed to enhance N loss of urea rather than reduce it,and did not show any benefit effect in improving the yield efficiency of urea,which is presumably due to the high potential of ammonia volatilization in the soil and climatic conditions under investigation.

  3. Study on the diagenetic calcareous accumulations in a soil profile from Floresti (Cluj County, Romania

    Directory of Open Access Journals (Sweden)

    Horea Bedelean

    2004-04-01

    Full Text Available The studied calcretes developed in two different levels (horizons in the soil profile from Floreşti (Cluj County. The deposits outcropping in the area are represented by Bartonian-Priabonian sedimentary rocks (Ciuleni Member, Viştea Limestone and the Quaternary horizon (terrace of Someşul Mic River, consisting of pebbles of different origin, which represent the parent rock of the soil. A detailed petrographical and mineralogical description of the calcretes is given below, based on macroscopic, microscopic and X-ray diffraction analysis. It led to the conclusion that the calcretes from the studied profile have a pedogenic origin. The calcretes consist of distinctive subhorizons within the host horizon of the soil. According to their microstructure, the studied calcretes belong to the alpha-type and may be considered as “nodular calcretes” or “glaebular calcretes”. The source of carbonate was variable: from the parent material of the soil including fragments of carbonate rocks, bioclasts, vegetal rests, eolian dust.

  4. Bioavailability of zinc and phosphorus in calcareous soils as affected by citrate exudation

    NARCIS (Netherlands)

    Duffner, A.; Hoffland, E.; Temminghoff, E.J.M.

    2012-01-01

    Aims Zinc (Zn) and phosphorus (P) deficiency often occurs at the same time and limits crop production in many soils. It has been suggested that citrate root exudation is a response of plants to both deficiencies. We used white lupin (Lupinus albus L.) as a model plant to clarify if citrate exuded by

  5. Controls over N2O, NOx and CO2 fluxes in a calcareous mountain forest soil

    Directory of Open Access Journals (Sweden)

    B. Kitzler

    2006-01-01

    Full Text Available We measured nitrogen oxides (N2O and NOx, dinitrogen (N2 and carbon dioxide (CO2 emissions from a spruce-fir-beech forest soil in the North Tyrolean limestone Alps in Austria. The site received 10.6–11.9 kg N ha−1 y−1 nitrogen as bulk deposition. Fluxes of nitric oxide (NO were measured by an automatic dynamic chamber system on an hourly basis over a two year period. Daily N2O emissions were obtained by a semi-automatic gas measuring system. In order to cover spatial variability biweekly manual measurements of N2O and CO2 emissions were carried out in addition. For acquiring information on the effects of soil and meteorological conditions and of N-deposition on N-emissions we chose the auto-regression procedure (time-series analysis as our means of investigation. Hence, we could exclude the data's autocorrelation in the course of the time. We found that soil temperature, soil moisture and bulk N-deposition followed by air temperature and precipitation were the most powerful influencing parameters effecting N-emissions. With these variables, up to 89% of observed temporal variations of N-emissions could be explained. During the two-year investigation period between 2.5 and 3.5% of deposited N was reemitted in form of N2O whereas only 0.2% were emitted as NO. At our mountain forest site the main end-product of microbial activity processes was N2 and trace gases (N2O and NO were only of minor importance.

  6. Certified reference material for the quality control of EDTA- and DTPA-extractable trace metal contents in calcareous soil (CRM 600)

    Energy Technology Data Exchange (ETDEWEB)

    Quevauviller, P. [European Commission, Standards, Measurements and Testing Programme, Brussels (Belgium); Lachica, M.; Barahona, E. [Estacion Experimental del Zaidin, Granada (Spain); Gomez, A. [Institut Nacional de Recherche Agronomique, Station d`Agronomie, Villenave d`Ornon (France); Rauret, G. [Universidad de Barcelona, Dept. de Quimica Analitica, Barcelona (Spain); Ure, A. [University of Strathclyde, Dept. of Pure and Applied Chemistry, Glasgow (United Kingdom); Muntau, H. [European Commission, Joint Research Centre, Environment Institute, Ispra (Italy)

    1998-03-01

    Single extraction tests are commonly used to study the eco-toxicity and mobility of metals in soils, e.g. to assess the bioavailable metal fraction (and thus to estimate the related phyto-toxic and nutritional deficiency effects) and the environmentally accessible trace metals upon disposal of e.g. sediment on to a soil (e.g. contamination of ground waters). However, the lack of uniformity in the different procedures does not allow the results to be compared worldwide nor the procedures to be validated. This paper describes the interlaboratory testing of EDTA- and DTPA-extraction procedures for soil analysis, followed by the preparation of a calcareous soil reference material (CRM 600), the homogeneity and stability studies and the analytical work performed for the certification of the EDTA- and DTPA- extractable contents of some trace metals (following the standardized extraction procedures). (orig.) With 2 figs., 7 tabs., 14 refs.

  7. Dryland, calcareous soils store (and lose) significant quantities of near-surface organic carbon

    Science.gov (United States)

    Cunliffe, Andrew M.; Puttock, Alan K.; Turnbull, Laura; Wainwright, John; Brazier, Richard E.

    2016-04-01

    Semiarid ecosystems are susceptible to changes in dominant vegetation which may have significant implications for terrestrial carbon dynamics. The present study examines the distribution of organic carbon (OC) between particle size fractions in near-surface (0-0.05 m) soil and the water erosion-induced redistribution of particle-associated OC over a grass-shrub ecotone, in a semiarid landscape, subject to land degradation. Coarse (>2 mm) particles have comparable average OC concentrations to the fine (events was monitored over four annual monsoon seasons. Eroded sediment was significantly enriched in OC; enrichment increased significantly across the grass-shrub ecotone and appears to be an enduring phenomenon probably sustained through the dynamic replacement of preferentially removed organic matter. The average erosion-induced OC event yield increased sixfold across the ecotone from grass-dominated to shrub-dominated ecosystems, due to both greater erosion and greater OC enrichment. This erosional pathway is rarely considered when comparing the carbon budgets of grasslands and shrublands, yet this accelerated efflux of OC may be important for long-term carbon storage potentials of dryland ecosystems.

  8. Organic and inorganic amendments affect soil concentration and accumulation of cadmium and lead in wheat in calcareous alkaline soils

    Science.gov (United States)

    Irrigation with untreated effluent in periurban agriculture could result in accumulation and bioconcentrations of cadmium (Cd) and lead (Pb). Different amendments were used to investigate their effect on availability, concentration, and uptake of metals by wheat in texturally different soils. Crop w...

  9. Comparison of chemical fertilizer and sewage sludge application on some nutrients’ bioavailability in three textural classes of a calcareous soil after harvesting spinach (Spinacia oleracea L.

    Directory of Open Access Journals (Sweden)

    H.R Boostani

    2012-12-01

    Full Text Available Sewage sludge (SS as a source of macro- and micro nutrients has been utilized in many countries for crop and vegetable production. To compare the influence of SS with chemical fertilizer on macro- and micro nutrients bioavailability in three textural classes of a calcareous soil after harvesting spinach (Spinacia oleracea L., a factorial experiment was carried out in a completely randomized design with two factors and three replications under glasshouse conditions. The first factor was SS levels (0, 10, 20, 40, and 80 mg per kg soil and the second factor was soil textural classes (sandy, sandy loam, and clay loam. A chemical fertilizer treatment was used for comparison with the applied SS treatments. Results indicated that total nitrogen (N and available phosphorus (P was significantly higher in SS amended soils compared to fertilizer treatment. Effect of increasing soil potassium (K due to addition of SS was less than P and N, which is probably due to low content of K in SS. Soil DTPA extractable iron, zinc, copper, and manganese were significantly increased in SS treatments in all soil textures and were higher than fertilizer treatment. Based on nutrients’ bioavailability in soil after harvesting spinach, especially at high rates of SS, addition of most nutrients is not necessary for the next crop. Concentration of DTPA extractable cadmium (Cd and lead (Pb was not detectable in all treatments. Therefore, because of low contents of Cd and Pb in the utilized SS, reaching to a toxic level of these elements in soil is unexpected. However, if high levels of SS are applied frequently, soil test is recommended for monitoring heavy metals concentration in amended soils. Prior to any SS recommendation, the results of this research need to be verified under field conditions.

  10. 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)

  11. Metal extractability patterns to evaluate (potentially) mobile fractions in periurban calcareous agricultural soils in the Mediterranean area-analytical and mineralogical approaches.

    Science.gov (United States)

    de Santiago-Martín, Ana; Valverde-Asenjo, Inmaculada; Quintana, Jose R; Vázquez, Antonio; Lafuente, Antonio L; González-Huecas, Concepción

    2013-09-01

    A set of periurban calcareous agricultural Mediterranean soils was spiked with a mixture of Cd, Cu, Pb and Zn at two levels within the limit values proposed by current European legislation, incubated for up to 12 months, and subjected to various one-step extraction procedures to estimate mobile (neutral salts) and potentially mobile metal fractions (complexing and acidic extraction methods). The results obtained were used to study metal extractability patterns according to the soil characteristics. The analytical data were coupled with mineralogical investigations and speciation modelling using the Visual Minteq model. The formation of soluble metal-complexes in the complexing extracts (predicted by the Visual Minteq calculations) led to the highest extraction efficiency with complexing extractants. Metal extractability patterns were related to both content and composition of carbonate, organic matter, Fe oxide and clay fractions. Potentially mobile metal fractions were mainly affected by the finest soil fractions (recalcitrant organic matter, active lime and clay minerals). In the case of Pb, scarce correlations between extractable Pb and soil constituents were obtained which was attributed to high Pb retention due to the formation of 4PbCO3·3PbO (corroborated by X-ray diffraction). In summary, the high metal proportion extracted with complexing agents highlighted the high but finite capacity to store potentially mobilizable metals and the possible vulnerability of these soils against environmental impact from metal accumulation.

  12. Total Phosphate Influences the Rate of Hydrocarbon Degradation but Phosphate Mineralogy Shapes Microbial Community Composition in Cold-Region Calcareous Soils.

    Science.gov (United States)

    Siciliano, Steven D; Chen, Tingting; Phillips, Courtney; Hamilton, Jordan; Hilger, David; Chartrand, Blaine; Grosskleg, Jay; Bradshaw, Kris; Carlson, Trevor; Peak, Derek

    2016-05-17

    Managing phosphorus bioaccessibility is critical for the bioremediation of hydrocarbons in calcareous soils. This paper explores how soil mineralogy interacts with a novel biostimulatory solution to both control phosphorus bioavailability and influence bioremediation. Two large bore infiltrators (1 m diameter) were installed at a PHC contaminated site and continuously supplied with a solution containing nutrients and an electron acceptor. Soils from eight contaminated sites were prepared and pretreated, analyzed pretrial, spiked with diesel, placed into nylon bags into the infiltrators, and removed after 3 months. From XAS, we learned that three principal phosphate phases had formed: adsorbed phosphate, brushite, and newberyite. All measures of biodegradation in the samples (in situ degradation estimates, mineralization assays, culturable bacteria, catabolic genes) varied depending upon the soil's phosphate speciation. Notably, adsorbed phosphate increased anaerobic phenanthrene degradation and bzdN catabolic gene prevalence. The dominant mineralogical constraints on community composition were the relative amounts of adsorbed phosphate, brushite, and newberyite. Overall, this study finds that total phosphate influences microbial community phenotypes whereas relative percentages of phosphate minerals influences microbial community genotype composition.

  13. In situ stabilization of As and Sb with naturally occurring Mn, Al and Fe oxides in a calcareous soil: bioaccessibility, bioavailability and speciation studies.

    Science.gov (United States)

    Bagherifam, Saeed; Lakzian, Amir; Fotovat, Amir; Khorasani, Reza; Komarneni, Sridhar

    2014-05-30

    This study investigated the effectiveness of 6 different types of naturally occurring manganese, aluminum and iron oxides for stabilization of As and Sb in a calcareous soil spiked with 50mgkg(-1) of As or Sb and two dosages of treatments (2% and 5%). The resulting contaminated soils were subjected to a series of chemical extraction studies including sequential extraction, single step extraction with DTPA and Simplified Bioaccessibility Extraction Test (SBET) for estimation of bioaccessible fraction of As and Sb in soil and a greenhouse experiment using barley as the test crop. The results showed that Fe-associated and carbonate-bound fraction of As and Sb were predominant fractions. However, the amounts of labile fractions were higher in As contaminated soils, whereas the percentage of Sb associated with crystalline Fe-oxide and residual fractions were higher. The results revealed that application of natural metal oxides reduced DTPA and SBET extractable amounts and plant uptake of As and Sb. After application of amendments, the exchangeable fraction of As decreased dramatically by up to 82% while Sb exchangeable fraction decreased by up to 60% depending upon the additive. The results of chemical extractions and plant uptake confirmed that Sb had lower bioavailability, compared with As.

  14. Evaluation of alkaline phosphatase activity and availability of various P fractions for bean (Phaseolus vulgaris in some calcareous soils amended with municipal sewage sludge

    Directory of Open Access Journals (Sweden)

    T. Raeisi

    2014-07-01

    Full Text Available To evaluate the relationship of various P fractions and alkaline phosphatase activity with bean indices growing in 10 calcareous soils, amended with municipal sewage sludge from Chaharmahal-Va-Bakhtiari province, a greenhouse research was carried out. Soil samples were incubated for one month with sludge at a rate equivalent to 1% (w/w. Then, the P fractions, including P adsorbed by Fe and Al oxides (]NaOH+CB]-P, occluded P (CBD-P and P absorbed by Ca (HCl-P, were determined by Olsen and Summers' sequential fractionation procedure. Furthermore, total P, organic P and residual P were determined. Also, alkaline phosphatase activity was measured. A pot experiment in a completely randomized design with three replications in the ten soils was done to evaluate the bean plant indices. The results showed that the amount of P fractions decreased in the following order: HCl-P>residual-P>]NaOH+CB]-P > OP>CBD-P. The results also indicated that alkaline phosphatase activity was significantly correlated with CBD-P fraction, organic P and total P. In addition, significant correlations were found between ([NaOH+CB]-P and HCl-P and plant shoots. In general, the results of this research showed that P fractionation method appears to be a powerful tool to identify the P status and availability in the soils amended with sewage sludge.

  15. 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

    2017-02-01

    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.

  16. 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

    2017-01-01

    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. PMID:28176865

  17. CO2 emission and structural characteristics of two calcareous soils amended with municipal solid waste and plant residue

    Science.gov (United States)

    Yazdanpanah, N.

    2016-01-01

    This investigation examines the effect of different amendments on selected soil physical and biological properties over a 24-month period in two cropland fields. Urban municipal solid waste (MSW) compost and alfalfa residue (AR) were used as different organic amendments at the rates of 0 (control), 10 and 30 Mg ha-1 to a clay loam soil and a loamy sand soil in a semiarid region. Results showed that the soil improvement was controlled by the application rate and decomposability of amendments and soil type. The addition of organic amendments to the soils improved aggregate stability and consequently enhanced total porosity, especially macropore fraction. The increased soil organic carbon (SOC) and total porosity values as compared to the control treatment were greater in the loamy sand soil than in the clay loam soil. Moreover, compared to the microbial respiration of control plots, the application of MSW resulted in higher values of microbial respiration in the clay loam soil than in the loamy sand soil, whereas the reverse was found for AR. Linear and power functions were provided for the relationships between microbial respiration and SOC in the loamy sand and clay loam soils, respectively. Also, CO2 emission was stimulated significantly as power functions of the total porosity and the ratio of macroporosity to microporosity. However, the soil microbial respiration and carbon storage improved aggregate stability and pore size distribution, and as a response, soil porosity, especially the macropore fraction, controlled CO2 flux.

  18. Organic Carbon Storage and Decomposition Rate of Three Subcategories of Calcareous Soil in Karst Area%桂林毛村岩溶区三种亚类石灰土有机碳矿化研究

    Institute of Scientific and Technical Information of China (English)

    严毅萍; 曹建华; 梁毅; 王培; 玉宏

    2012-01-01

    three sub-categories are following the order: black calcareous soilbrown calcareous soilred calcareous soil,the black calcareous soil mineralization rate is much greater than that of brown and red calcareous soils,in which the differences in 0~20 cm soil layer are largest.Mineralization rate of SOC and SOC contents displayed a positive correlattion.Black calcareous soil has the highest fraction of cumulative CO2-C released by SOC mineralization,and reached 3.33%.Secondly the fraction of the red calcareous soil is 2.92%.The Brown calcareous soil of cultivated land has the lowest fraction of cumulative CO2-C released by SOC mineralization by 1.90%,indicating that the stability of black calcareous soil and Red calcareous soil were weakly than Brown calcareous soil.The Brown calcareous soil of cultivated land has a strong capability to fix organic carbon.

  19. Effect of zinc rates, arbuscular mycorrhiza and two types of organic matter on corn growth and micronutrients-uptake in a calcareous soil

    Directory of Open Access Journals (Sweden)

    L. Gholami

    2016-09-01

    Full Text Available A greenhouse experiment was conducted to study the effect of zinc rates, arbuscular mycorrhiza and organic matter, on corn growth and micronutrients-uptake in a calcareous soil. Experimental design was factorial based on complete randomized design with 3 replications. Treatments consisted of 3 levels of Zn (0, 5 and 10 mg Zn/kg, 2 types of organic manure (sheep manure and municipal waste compost, each at 0 or 1% w/w and 2 levels of mycorrhiza (no inoculation and inoculation with Glomus intraradices. Plants were harvested 8 weeks after emergence and used for chemical analysis. Roots were used to determine the degree of colonization. Results showed that application of Zn increased plant dry matter weight, total Zn and Cu uptake, root mycorrhizal colonization and decreased total Fe and Mn uptake. Arbuscular mycorrhiza increased plant dry matter weight, root mycorrhizal colonization and total Zn, Fe, Mn and Cu uptake. Application of both organic manures increased plant dry matter weight, root mycorrhizal colonization and total Zn, Fe, Mn and Cu uptake. 

  20. 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.

  1. 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.

  2. 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.

  3. Role of Carbon Substrates Added in the Transformation of Surplus Nitrate to Organic Nitrogen in a Calcareous Soil

    Institute of Scientific and Technical Information of China (English)

    QIU Shao-Jun; JU Xiao-Tang; J.INGWERSEN; GUO Zi-De; C.F.STANGE; R.BISHARAT; T.STRECK

    2013-01-01

    Excessive amounts of nitrate have accumulated in many soils on the North China Plain due to the large amounts of chemical N fertilizers or manures used in combination with low carbon inputs.We investigated the potential of different carbon substrates added to transform soil nitrate into soil organic N (SON).A 56-d laboratory incubation experiment using the 15N tracer (K15NO3)technique was carried out to elucidate the proportion of SON derived from accumulated soil nitrate following amendment with glucose or maize straw at controlled soil temperature and moisture.The dynamics and isotopic abundance of mineral N (NO3-and NH4+) and SON and greenhouse gas (N2O and CO2) emissions during the incubation were investigated.Although carbon amendments markedly stimulated transformation of nitrate to newly formed SON,this was only a substitution effect of the newly formed SON with native SON because SON at the end of the incubation period was not significantly different (P > 0.05) from that in control soil without added C.At the end of the incubation period,amendment with glucose,a readily available C source,increased nitrate immobilization by 2.65 times and total N2O-N emission by 33.7 times,as compared with maize straw amendment.Moreover,the differences in SON and total N2O-N emission between the treatments with glucose and maize straw were significant (P < 0.05).However,the total N2O-N emission in the straw treatment was not significantly (P > 0.05) greater than that in the control.Straw amendment may be a potential option in agricultural practice for transformation of nitrate N to SON and minimization of N2O emitted as well as restriction of NO3-N leaching.

  4. Prospects of damaged calcareous spring systems in temperate Europe : Can we restore travertine-marl deposition?

    NARCIS (Netherlands)

    Grootjans, Ab; Bulte, Marc; Wolejko, Leslaw; Pakalne, Mara; Dullo, Bikila; Eck, Nelly; Fritz, Christian

    2015-01-01

    Calcareous mires are peat forming systems fed by calcareous groundwater that regularly deposit travertine (CaCO3) on the soil surface or in small pools that are present in such mires. At present almost all calcareous mires in Poland are degraded, most often by land use, which has led to disturbances

  5. Changes in the distribution of Zn applied as a mixture of synthetic chelating agents in two successive flax crops grown in a calcareous soil.

    Science.gov (United States)

    Almendros, P.; Gonzalez, D.; Obrador, A.; Alvarez, J. M.

    2012-04-01

    significant decreases in both the Zn-D-H-E treatments, with reductions ranging from 38.1 to 52.6% of the initial Zn values (Zn-D-H-E applied at 5 and 10 mg Zn kg-1, respectively). Similar behaviour was also observed in Zn-MnOX with both the Zn-D-H-E treatments, with the reductions ranging from 36.6 to 43.5% of the initial Zn values (Zn-D-H-E at 5 and 10 mg Zn kg-1, respectively). In contrast, the Zn concentrations associated with the CAR and FeOX forms showed significant increases between the two successive flax crops for all the treatments, including that of Nil-Zn. These increases in Zn-CAR ranged from 41.0 to 43.6% of initial Zn (Zn-D-H-E at 5 mg Zn kg-1 and Nil-Zn and, respectively). For Zn-FeOX, the corresponding increases ranged from 56.0 to 186.8% of initial Zn (Zn-D-H-E at 10 mg Zn kg-1 and Nil-Zn, respectively). Zinc concentrations associated with OM and RES fractions did not show any significant differences between the two flax crops for the different treatments. Finally, the residual effect of this calcareous soil produced a change in the distribution of Zn fractions, mainly from water soluble, exchangeable and easily reducible Zn to carbonate bound and Fe oxide bound Zn.

  6. 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.

  7. Effect of salinity and vermicompost application on nutrients concentration and yield of spinach cv. Virofly in a calcareous soil

    Directory of Open Access Journals (Sweden)

    J. Sheikhi

    2013-04-01

    Full Text Available To evaluate the effect of salinity (S and vermicompost (V on yield and concentration of nitrogen (N, phosphorus (P, potassium (K, iron (Fe, manganese (Mn, zinc (Zn, copper (Cu, calcium (Ca, magnesium (Mg, sodium (Na and chlorine (Cl of spinach shoots cv. Virofly, a pot experiment was conducted in greenhouse, and arranged as factorial in a completely randomized design with three replications. Treatments included three V levels (0, 1 and 2%, w/w and four S levels (0, 1, 2 and 3 g NaCl per kg soil. Electrical conductivity of the soil for these four S levels was 0.7, 4.5, 8 and 11.5 dS/m, respectively. Results showed that the highest yield of spinach shoots was obtained in 10% V treatment. Application of sodium chloride (NaCl had no significant effect on shoot yield. Therefore, under the present experimental conditions, S threshold level for "Viroflay" cultivar was at least 11.5 dS/m, which is much higher than the level reported in literature for spinach (2 dS/m. Application of V increased concentration of N, P, K, Fe and Mg in spinach shoots, but decreased concentration of Mn, Zn, Cu, Ca, Na and Cl. Application of NaCl had no significant effect on the concentration of P, Fe, Mn, Ca and Mg. But, with the addition of NaCl, concentration of N, Zn, Cu, Na and Cl was increased in spinach shoots. In the absence of NaCl, application of V had no significant effect on Na concentration, but increased Cl concentration. Whereas, at 3 g NaCl level, application of V significantly decreased Na and Cl concentrations of shoots, compared to the application of NaCl alone. Therefore, application of V not only can increase plant growth, but also could be an effective solution to mitigate the negative effects of high concentrations of Na and Cl on growth of spinach, cv. Virofly, in saline soils.

  8. Effect of Different Fertilizer Treatments on Quantity of Soil Microbes and Structure of Ammonium Oxidizing Bacterial Community in a Calcareous Purple Paddy Soil

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The quantity of soil microbes and the structure of ammonium oxidizing bacterial (AOB) community were analyzed using the dilution plate counting and most probable number method (MPN), and denaturing gradient gel electrophoresis (DGGE), respectively. Fertilizer application tended to increase the number of soil microbes and alter the AOB community compared to the control with no fertilizer application (CK). Among the eight fertilizer treatments, soil samples from the treatments of mineral fertilizers (e.g., N, P, K) in combination with farmyard manure (M) had greater numbers of soil microbes and more complex structure of AOB community than those receiving mineral fertilizers alone. The principal component analyses (PCA) for ammonium oxidizing bacterial community structure showed that the eight fertilizer treatments could be divided into two PCA groups (PCA1 and PCA2). For the soil sampled after rice harvest, PCA1 included NP, NM, NPM and NPKM fertilizer treatments, while PCA2 was consisted of CK, N, M and NPK fertilizer treatments. For soil samples collected after wheat harvest, PCA1 was consisted of M, NM, NPM and NPKM fertilizer treatments, while PCA2 was composed of CK, N, NP and NPK fertilizer treatments. For a given rotation, the richness of AOB community in PCA1 was greater than that in PCA2. In addition, AOB community structure was more complex in the soil after rice harvest than that after wheat harvest. The results indicated that different fertilizer treatments resulted in substantial changes of soil microbe number and AOB community. Furthermore, mineral fertilizers (N, NP, NPK) combined with farmyard manure were effective for increasing the quantity of soil microbes, enriching AOB community, and improving the soil biofertility.

  9. Effects of Long-term Located Fertilization on the Physiochemical Properties of Non-calcareous Alluvial Soil%长期定位施肥对无石灰性潮土理化性质的影响

    Institute of Scientific and Technical Information of China (English)

    赵秀芬; 李俊良

    2009-01-01

    [目的]为改善土壤理化性质和促进农业可持续发展提供理论依据.[方法]通过田间试验研究长期定位不同施肥对无石灰性潮土理化性质的影响.[结果]单施有机肥处理的土壤含水量最高,CK的土壤含水量最低.施用有机肥处理的土壤容重较小,CK和无机肥处理的土壤容重较大.施用有机肥处理的土壤孔隙度显著高于不施有机肥处理和CK.施用有机肥、化肥处理和CK的土壤有机质含量分别约为原始土样的7.5、2.8和2.3倍.施用有机肥处理的土壤pH值提高了0.62,施用无机肥处理的土壤pH值降低.长期定位不同施肥对土壤速效养分氮磷钾含量的影响为:有机-无机肥料配施>单施大量有机肥>无机肥配施>单施氮肥>不施肥.[结论]有机-无机肥料配施能有效改善无石灰性潮土的理化性质.%[Objective]The purpose of the research was to supply theoretical basis for improving the physiochemical properties of soil and promoting agricultural sustainable development. [Method]The effects of applying different fertilizers in long-term located fertilization on the physiochemical properties of non-calcareous alluvial soil were researched through field experiment. [Result]The soil water content in the treatment with organic fertilizer only was highest and that in CK was lowest. The soil buil density in the treatment with organic fertilizer was smaller and that in CK and the treatment with inorganic fertilizer were bigger. The soil porosity in the treatment with organic fertilizer was significantly higher than that in the treatment without organic fertilizer and CK. The soil organic matter contents in the treatments with organic fertilizer, chemical fertilizer and CK were about 7.5, 2.8 and 2.3 times of that in the original soil samples resp. The soil pH value in the treatment with organic fertilizer was enhanced by 0.62 and that in the treatment with inorganic fertilizer was decreased. The effects of

  10. 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...

  11. 脲酶抑制剂对石灰性土壤尿素转化及N2O排放的影响%Responses of Urea Transformation Dynamics and Nitrous Oxide to Three Urease Inhibitors in Calcareous Soil

    Institute of Scientific and Technical Information of China (English)

    李君; 刘涛; 褚贵新

    2014-01-01

    通过研究脲酶抑制剂对土壤中尿素转化的影响,揭示土壤各形态氮对N2O的贡献,为控制石灰性土壤氮素损失及提高氮肥利用率提供理论依据。在室内恒温培养条件下(25℃),研究了正丁基硫代磷酰三胺(NBPT)、醋酸棉酚、硫代硫酸铵3种脲酶抑制剂对石灰性土壤各形态氮素转化与脲酶抑制率的影响,同时在人工气候室(昼夜)通过Unisense N2O微电极法对各处理土壤N2O浓度进行了原位实时监测。结果表明:尿素施入土壤1 d后50%已迅速水解,3 d后完全水解。1~14 d各脲酶抑制剂均可显著抑制尿素水解,尿素+NBPT处理的土壤尿素残留量显著高于其他处理,其脲酶抑制率为33.6%;NBPT处理的土壤NH+4-N含量低于其他各处理(Purea+GA>urea+ATS≥urea+NBPT. Furthermore, N2O concentrations were higher during the day than at night, with diurnal variation ranging from 0.25~3.15μmol·L-1. The path coefficients between N2O concentration and different forms of soil mineral N were:NO-3-N(0.641)>NH+4-N(0.356)>Urea-N(0.255). There was a significant positive relationship between soil NO-3-N and N2O contents, indicating that soil nitrate would be one of key factors influencing soil N2O emission. In conclusion, applying NBPT, ATS and GA inhibits urea hydrolysis and decreases soil N2O generation in calcareous soil, with NBPT as a promising urease inhibitor.

  12. Reducing the infectivity and richness of ectomycorrhizal fungi in a calcareous Quercus ilex forest through soil preparations for truffle plantation establishment: A bioassay study.

    Science.gov (United States)

    Garcia-Barreda, Sergi; Molina-Grau, Sara; Reyna, Santiago

    2015-11-01

    In the early years of a black truffle plantation, the field proliferation of the nursery-inoculated fungi can be hampered by native ectomycorrhizal fungi colonising the seedling roots. Reducing the soil ectomycorrhizal infectivity in the planting hole before introducing the inoculated seedling could be an effective strategy to reduce this problem. Three bioassays were conducted to evaluate the impact of several soil preparations on the ectomycorrhizal infectivity and richness of a Quercus ilex soil in a truffle-producing region. Microwaves, quicklime, and acetic acid significantly decreased the percent root colonisation and morphotype richness of the native ectomycorrhizal fungi. However, they also decreased seedling survival or growth. Peracetic acid, hydrogen peroxide, and sodium hypochlorite did not show a significant negative effect on the soil ectomycorrhizal community. The results support the potential of soil preparation for reducing the ectomycorrhizal infectivity of forest soils, thus being a promising strategy to reduce the early colonisation by native fungi in truffle plantations. However, the indications of damage to the seedling development must be addressed.

  13. The use of natural abundance carbon-13 to identify and quantify sources of emitted carbon dioxide in a calcareous southern Ontario Luvisolic soil

    Science.gov (United States)

    Wilton, Meaghan

    Three studies Were conducted at the Elora Research Station (ERS) on a Luvisolic soil to investigate the soil inorganic carbon (SIC) and soil organic carbon (SOC) components contributing to the CO2 flux (FC) using natural 13C abundance. SIC contributed to the FC in intact soil incubations. Soil disruption exacerbated the release of CO2 from both pedogenic and lithogenic carbonates. Field and laboratory techniques to obtain the delta13C of respired CO2 (delta13CR) were compared. Short-term deployment of non flow-through non steady-state chambers and the use of the simple two-ended mass balance approach to derive delta 13CR were found acceptable to apply to the ERS site. The delta13CR from a corn field at ERS with a history of multiple C4 and C3 crop rotations was partitioned into SIC and SOC components using two approaches. Root respiration contributed 2% - 64% and carbonates contribute up to 20% to the FC.

  14. Effect Comparison of Three Different Types of Nitrification Inhibitors (DCD, DMPP and Nitrapyrin) in Calcareous Soils%三种硝化抑制剂在石灰性土壤中的应用效果比较

    Institute of Scientific and Technical Information of China (English)

    刘涛; 梁永超; 褚贵新; 马丹; 刘倩; 王健

    2011-01-01

    Nitrification inhibitors can increase N fertilizer use efficiency and decrease the potential N pollution. Incubation experiment was conducted in sandy and clay calcareous soils incubated in growth chamber at 25°C in dark condition in order to compare the effect of three different types of nitrification inhibitors (NI), namely, dicyandiamide (DCD), 3, 4-dimethylpyrazole phosphate (DMPP) and Nitrapyrin on (NH4)2SO4 nitrification inhabitation. During 30 days incubation tine, an obvious nitrification inhibitions were observed after nitrification inhibitors applied, soil NH+4-N contents were improved by 228.45 - 244.85 mg/kg and 209.75 - 254.79 mg/kg in sandy and clay soil respectively, while soil NO3'-N contents were reduced by 93.85% - 94.99% and 91.82% - 95.38% in sandy soil and clay soil respectively. Significant nitrifications were occurred, soil apparent nitrification rates under control condition (CK) were increased by 86.00% and 80.89% while were only improved by 1.28% - 2.09% and 2.72% - 8.40% in sandy soil and clay soil respectively after nitrification inhibitors added. From above results the conclusion can be made that DCD, DMPP and Nitrapyrin all three nitrification inhibitors exert an obviously nitrification inhibition effect, nitrification rate in sandy soil were higher than that in clay soil, the order of inhibition effects were as follow: DMPP>Nitrapyrin>DCD.%在人工气候室内采用25℃黑暗培养法研究双氰胺(DCD)、3,4-二.甲基吡唑磷酸(DMPP)及2-氯-6-三氯甲基吡啶(Nitrapyrin)在石灰性土壤中的硝化抑制效果.结果表明:施用DCD、DMPP、Nitrapyrin的土壤NH4+-N含量较单施硫酸铵的土壤(对照)分别提高228.45~244.85 mg/kg(砂土)、209.75~254.79 mg/kg(黏土),NO3--N含量较对照分别降低93.85%~94.99%(砂土)、91.82%~95.38%(黏土).表观硝化率随培养进程增加缓慢,培养期间只增加了1.28%~2.09%(砂土)、2.72%~8.40%(黏土),而对照增加了86.00%(砂

  15. 长期定位施肥对石灰性紫色水稻土古菌群落结构的影响%Effect of long-term fertilization on archaeal community structure in calcareous purplish paddy soil

    Institute of Scientific and Technical Information of China (English)

    辜运富; 张小平; 涂仕华; Kristina Lindstr(o)m

    2011-01-01

    为了认识长期施肥对石灰性紫色水稻土培肥和肥力演化的作用,结合变性梯度凝胶电泳(denaturing gradient gel electrophoresis,DGGE)和限制性酶切片段长度多态性(RFLP)技术,研究了稻麦轮作下农家肥(M)、氮肥+农家肥(NM)、氮磷肥+农家肥(NPM)、氮磷钾肥+农家肥(NPKM)、无肥(CK)、氮肥(N)、氮磷肥(NP)、氮磷钾肥(NPK)等不同施肥制度对石灰性紫色水稻土古菌群落结构的影响.研究结果表明,长期定位施肥明显影响土壤中的古菌组成.在长期施用氮肥+农家肥、氮磷肥和氮磷钾肥+农家肥处理的土壤中,古菌多样性指数低于农家肥、氮磷肥+农家肥、无肥、氮肥和氮磷钾肥处理.在DGGE图谱的基础上,分别选择种植水稻和小麦的氮磷钾肥处理土壤样品,对古菌克隆子的16S rDNA序列进行了系统发育分析,发现水稻七古菌与各种土壤及水体环境的古菌极其相似.对DGGE图谱的聚类分析发现,不管是种植水稻还是小麦,8种施肥处理的古菌都聚在3个群里.种植水稻时,M和NPK处理下的土壤古菌聚成第一个群,NP处理下的聚成第二个群,另外5种施肥处理(NPKM,NM,Ck,N和NPM)聚成第三个群.种植小麦时,NPKM和M处理下的土壤古菌聚成一个群,NP处理下的聚成第二个群,N、NPK、NM、NPM和CK处理下的聚成第三个群.聚类分析结果显示,作物类型会影响土壤古菌群落结构.%To better understand the role that fertilization systems play in soil fertility buildup and evolution,we employed denaturing gradient gel electrophoresis (DGGE) and restriction fragment length polymorphism (RFLP) to determine the influence of different fertilization treatments on archaeal community structure in calcareous purplish paddy soil under rice/wheat rotations. The eight fertilization treatments were as follows:manure only (M), nitrogen plus manure (NM), nitrogen and phosphorus plus manure (NPM), nitrogen,phosphorus and potassium plus

  16. The influence of mineral fertilizer combined with a nitrification inhibitor on microbial populations and activities in calcareous Uzbekistanian soil under cotton cultivation.

    Science.gov (United States)

    Egamberdiyeva, D; Mamiev, M; Poberejskaya, S K

    2001-10-30

    Application of fertilizers combined with nitrification inhibitors affects soil microbial biomass and activity. The objective of this research was to determine the effects of fertilizer application combined with the nitrification inhibitor potassium oxalate (PO) on soil microbial population and activities in nitrogen-poor soil under cotton cultivation in Uzbekistan. Fertilizer treatments were N as urea, P as ammophos, and K as potassium chloride. The nitrification inhibitor PO was added to urea and ammophos at the rate of 2%. Three treatments--N200 P140 K60 (T1), N200 PO P140 K60 (T2), and N200 P140 PO K60 (T3) mg kg(-1) soil--were applied for this study. The control (C) was without fertilizer and PO. The populations of oligotrophic bacteria, ammonifying bacteria, nitrifying bacteria, denitrifying bacteria, mineral assimilating bacteria, oligonitrophilic bacteria, and bacteria group Azotobacter were determined by the most probable number method. The treatments T2 and T3 increased the number of oligonitrophilic bacteria and utilization mineral forms of nitrogen on the background of reducing number of ammonifying bacteria. T2 and T3 also decreased the number of nitrifying bacteria, denitrifying bacteria, and net nitrification. In conclusion, our experiments showed that PO combined with mineral fertilizer is one of the most promising compounds for inhibiting nitrification rate, which was reflected in the increased availability and efficiency of fertilizer nitrogen to the cotton plants. PO combined with mineral fertilizer has no negative effects on nitrogen-fixing bacteria Azotobacter and oligo-nitrophilic bacteria.

  17. The influence of wine-distillery waste compost on nitrogen and phosphorus dynamics and uptake by a melon crop in a shallow calcareous soil

    Science.gov (United States)

    Requejo, M. I.; Villena, R.; Ribas, F.; Castellanos, M. T.; Cabello, M. J.; Arce, A.; Cartagena, M. C.

    2012-04-01

    In Mediterranean countries, the large quantity of organic wastes generated by the winery industry constitutes a serious environmental concern, due to its low pH and high content of phenolic compounds. This is accompanied by a seasonal production that makes their management difficult. Winery wastes are characterized by high organic matter contents, low electrical conductivity values and notable contents in macronutrients, so their use as organic amendments is a good management option for improving soil fertility. However, a composting treatment is necessary to convert these organic wastes into more stable, hygienic and humic-rich materials. The aim of this work was to evaluate the effects of the application of exhausted grape marc compost (composed of dealcoholized pulp, skins and stems) as fertilizer in soil nitrogen and phosphorus availability and uptake by a melon crop (Cucumis melo L.). This experiment was carried out from May to September 2011 in Ciudad Real (Spain). This area was designated "vulnerable zone" by the "Nitrates Directive" 91/676/CEE. The soil was a shallow sandy-loam (Alfisol Xeralf Petrocalcic Palexeralfs) with a depth of 0.60 m and a discontinuous petrocalcic horizon between 0.60 and 0.70 m, slightly basic (pH 7.9), poor in organic matter (0.20%), rich in potassium (407 ppm) and with a medium level of phosphorus (19.4 ppm). The experiment had a randomised complete block design, with four treatments consisted of four compost doses: 0 (D0), 6.7 (D1), 13.3 (D2) and 20 T compost ha-1 (D3), in order to determine the optimum dose to ensure nutrient demand, maximizing yield and minimizing nutrient losses. Acknowledgements This project has been supported by INIA-RTA2010-00110-C03-01.

  18. The Influence of Mineral Fertilizer Combined With a Nitrification Inhibitor on Microbial Populations and Activities in Calcareous Uzbekistanian Soil Under Cotton Cultivation

    Directory of Open Access Journals (Sweden)

    Dilfuza Egamberdiyeva

    2001-01-01

    Full Text Available Application of fertilizers combined with nitrification inhibitors affects soil microbial biomass and activity. The objective of this research was to determine the effects of fertilizer application combined with the nitrification inhibitor potassium oxalate (PO on soil microbial population and activities in nitrogen-poor soil under cotton cultivation in Uzbekistan. Fertilizer treatments were N as urea, P as ammophos, and K as potassium chloride. The nitrification inhibitor PO was added to urea and ammophos at the rate of 2%. Three treatments—N200P140K60 (T1, N200 P140 POK60 (T2, and N200 P140 POK60 (T3 mg kg-1 soil—were applied for this study. The control (C was without fertilizer and PO. The populations of oligotrophic bacteria, ammonifying bacteria, nitrifying bacteria, denitrifying bacteria, mineral assimilating bacteria, oligonitrophilic bacteria, and bacteria group Azotobacter were determined by the most probable number method. The treatments T2 and T3 increased the number of oligonitrophilic bacteria and utilization mineral forms of nitrogen on the background of reducing number of ammonifying bacteria. T2 and T3 also decreased the number of nitrifying bacteria, denitrifying bacteria, and net nitrification. In conclusion, our experiments showed that PO combined with mineral fertilizer is one of the most promising compounds for inhibiting nitrification rate, which was reflected in the increased availability and efficiency of fertilizer nitrogen to the cotton plants. PO combined with mineral fertilizer has no negative effects on nitrogen-fixing bacteria Azotobacter and oligo-nitrophilic bacteria.

  19. 不同浓度DMPP和DCD对石灰性土壤中氮素转化的影响%Effects of Different Application Rates of DMPP and DCD on Nitrogen Transformation in Calcareous Soil

    Institute of Scientific and Technical Information of China (English)

    石美; 梁东丽; 满楠; 郭璐; 赵文龙; 王朝辉

    2012-01-01

    [目的]研究不同浓度硝化抑制剂3,4-二甲基吡唑磷酸(DMPP)和双氰胺(DCD)对石灰性土壤中氮素转化的影响,筛选出适宜石灰性土壤施用的DMPP和DCD最佳浓度,为其进一步在生产实践中的施用提供参考.[方法]采用室内培养的试验方法,在相同培养条件(土壤水分含量为田间持水量(WHC)的60%,温度为25℃)下,通过测定不同浓度DMPP(含氮量的0.5%、1%、2.5%和5%)和DCD(含氮量的2.5%、5%、10%和15%)处理土壤中各种形态氮素含量,评价不同浓度DMPP和DCD的抑制效果.[结果]施加不同浓度DMPP和DCD的土壤铵态氮含量均显著高于CK,而硝态氮和亚硝态氮含量显著低于CK.石灰性土壤中施用DMPP和DCD均能显著降低土壤的氨氧化速率,土壤铵态氮的半衰期从CK处理的3.6d分别增加到14.1-17.1 d和13.1-26.8 d.不同浓度的DMPP间氨氧化速率差异不显著;而DCD处理的氨氧化速率随其浓度的增加而下降,亦即土壤铵态氮浓度的半衰期随施用浓度的增加而显著增加.除CK外,各处理氨氧化速率常数k相比,以2.5%DCD最小,15%DCD最大;DMPP与DCD相比较,除DCD最低浓度处理外(2.5%),所有DCD处理的氨氧化速率均大于DMPP.[结论]硝化抑制剂DMPP和DCD均能显著抑制铵态氮向硝态氮的氧化进程,DMPP各浓度处理抑制效果差异不显著,DCD各浓度处理间差异显著,5%DCD与DMPP各浓度处理间无显著差异.因此,建议DCD的施用量为含氮量5%,而DMPP的施用量为含氮量的0.5%.%[Objective] A simulating experiment was carried out to study the effects of different concentrations of DMPP and DCD on nitrogen transformation in calcareous soil, and the best application rate was screened to provide references for agricultural practice. [Method] In the same incubation condition (soil moisture: 60% of water hold capacity, 25℃), the effects of different concentrations of DMPP (0.5%, 1%, 2.5% and 5% of applied pure N) and

  20. 长期定位施肥对石灰性紫色水稻土AMF多样性的影响%Effects of long-term fertilization on arbuscular mycorrhizal fungi community in calcareous purple paddy soil

    Institute of Scientific and Technical Information of China (English)

    辜运富; 李芳; 张小平; 涂仕华; KRISTINA Lindstr(o)m

    2012-01-01

    为了解长期定位施肥对石灰性紫色水稻土丛枝菌根真菌(AMF)物种多样性的影响,从稻麦轮作下连续26年定位施农家肥(M)、氮肥+农家肥(NM)、氮磷肥+农家肥(NPM)、氮磷钾肥+农家肥(NPKM)、不施肥(CK)、氮肥(N)、氮磷肥(NP)、氮磷钾肥(NPK)等不同施肥处理小区采集根区土样,分离鉴定AMF、测定多样性特征.共鉴定出17种AMF,其中球囊霉属Glomus 12种,占己分离总数的70.5%,为优势属;无梗囊霉属Acaulospora 3 种,占17.6%;原囊霉属Archaeospora和内养囊霉属Entrophospora各1种,各占5.9%.无论是石灰性紫色十种植水稻还是小麦,AMF侵染率最高的施肥处理均为无肥处理(CK),施肥特别是磷肥,降低AMF侵染率、孢子密度、相对多度和种丰度.变性梯度凝胶电泳(denaturing gradient gel electrophoresis,DGGE)分析结果表明,不施肥对照(CK)的AMF多样性最丰富,多样性指数最高,水稻和小麦种植下的多样性指数分别为2.68和3.02;与无机肥处理相比,农家肥配施无机肥提高了AMF多样性指数.农家肥配施无机肥更有利于AMF发育.%To determine the influence of long term fertilization on arbuscular mycorrhizal fungi (AMF) species diversity in calcareous purplish paddy soil, rhizosphere soil samples collected from different designed plots continuously supplied with manure only (M), nitrogen fertilizer plus manure (NM), nitrogen and phosphoric fertilizer plus manure (NPM), nitrogen, phosphoric and potassium fertilizer plus manure (NPKM), mineral nitrogen (N), nitrogen-phosphoric fertilizer (NP), nitrogen and phosphoric and potassium fertilizer (NPK) and without treatment (CK), under rice-wheat rotations for 26 years were mycologically investigated. The results showed that there are 17 species of AMF, among them, 12 species belong to Glomus, accounting for 70.5 percent of the total isolated species. Three species belong to Acaulospora, accounting for 17.6 percent of the isolated species

  1. Calcareous tubeworms of the Phanerozoic

    Directory of Open Access Journals (Sweden)

    Vinn, Olev

    2009-12-01

    Full Text Available Morphological similarities indicate that Palaeozoic problematic tubeworms, e.g. tentaculitids, cornulitids, microconchids, trypanoporids, Anticalyptraea, and Tymbochoos, form a monophyletic group. This group may also include hederelloids. Members of this group share affinities with lophophorates and their evolution could have partly been driven by predation. The extinction of Palaeozoic tubeworms in the Middle Jurassic was possibly at least partly caused by the ecological pressure by serpulid and sabellid polychaetes. The input of Palaeozoic tubeworms to the general ocean biocalcification system may have been smaller in the Ordovician to Jurassic than that of calcareous polychaetes in the Late Triassic to Recent. There seems to have been some correlation between the aragonite–calcite seas and the skeletal mineralogy of Triassic–Recent polychaete tubeworms.

  2. Combined effects of bio-fertilizer and citric acid on turf quality and soil biology on a calcareous soil%菌肥与柠檬酸互作对石灰性土壤生物学特性及草坪质量的影响

    Institute of Scientific and Technical Information of China (English)

    刘强; 姚拓; 马晖玲

    2014-01-01

    Nutrient management is an essential part of turf management;nitrogen (N)and phosphate (P)fer-tilizers are commonly applied to improve turf quality.However,little research on the effect of supplementary fertilizers,such as citric acid and bio-fertilizer,on turf quality has been carried out.This study was initiated to examine the effects of the combined application of citric acid and bio-fertilizer on the turf quality and soil biolog-ical characteristics on a calcareous soil.The results revealed that the combination of citric acid and bio-fertiliza-tion significantly increased the population of soil microorganisms,especially actinomycetes in the lower soil profile.Citric acid significantly improved the level of available phosphorus and the combination of citric acid and bio-fertilizer significantly improved turf quality provided N &P fertilizer application was adequate.%在草坪的日常管理中,肥料施用是一个必不可少的环节。在实际生产中,一般通过常规的氮、磷肥施用促进草坪草的生长,达到提高和改善草坪质量的目的,而通过施用微生物肥料和柠檬酸等辅助性肥料来改善土壤微生物环境、提高土壤养分有效性,从而促进草坪的生长方面研究较少。本文研究了柠檬酸和促生菌肥的互作处理对冷季型草坪质量及土壤生物学特性的影响,从而探讨柠檬酸和促生菌肥提高草坪草质量的机理,为草坪的科学管理提供理论依据。研究表明,1)一定量菌肥配合柠檬酸增加了石灰性土壤中微生物数量,尤其是深层土壤放线菌数量,且提高了土壤蔗糖酶和脲酶的活性。2)柠檬酸的施用,显著提高了土壤中有效磷含量。3)在一定量的氮、磷肥施用水平下,柠檬酸和促生菌肥有效提高了草坪质量。

  3. Effects of Nitrification Inhibitors on Nitrification Inhibition and Nitrite Accumulation in Calcareous Soil%石灰性土壤中不同硝化抑制剂的抑制效果及其对亚硝态氮累积的影响

    Institute of Scientific and Technical Information of China (English)

    石美; 张妹婷; 沈锋; 梁东丽; 党虎玲

    2011-01-01

    [Objective] The objective of the study was to determine the influences of four different kinds of nitrification inhibitors, DMPP, DCD, AM and TU, on soil nitrite accumulation, and to select the best nitrification inhibitor for nitrogen fertilizer in calcareous soil. [Method] The contents of ammonium nitrogen, nitrite nitrogen, nitrate nitrogen and pH were measured, and apparent nitrification rate and inhibitory rate of different nitrification inhibitors were calculated. [Result] The results showed that under the experimental conditions (60% of water hold capacity, 25℃), little nitrite nitrogen was found in the soil treated with nitrification inhibitors DMPP, DCD, and AM, however; while some nitrite nitrogen was found in the TU treatment in the beginning eight days. The nitrification inhibition rate was in the order of 10%DCD > 1%DMPP > 5%AM (depending on the amount of applied pure N). DMPP, DCD and AM treatments induced nitrification process lag behind 35-39 d. [ Conclusion ] DMPP, DCD and AM could significantly inhibit the accumulation of nitrite nitrogen in calcareous soil. The inhibitory effects of DMPP, DCD and AM were evident, while that of TU was not.%[目的]比较不同硝化抑制剂3,4-二甲基吡唑磷酸(DMPP),双氰胺(DCD)、2-氨基-4-氯-6-甲基吡啶(AM)和硫脲(TU)在石灰性土壤中的抑制效果,明确其对土壤中亚硝态氮累积的影响.[方法]采用室内培养的方法,比较了硝化抑制剂对石灰性土壤中铵态氮,硝态氮、亚硝态氮、pH、表观硝化率和硝化抑制率的影响.[结果]施用TU和未施用硝化抑制剂的土壤在培养初期(1-3 d)出现了亚硝态氮的累积.TU的施用导致土壤pH下降至硝化作用适宜的范围,从而促进了硝化作用进程;施用硝化抑制剂DMPP、DCD和AM的土壤几乎未检测到亚硝态氮,且硝化抑制效果明显,硝化过程延滞35-39 d.硝化抑制率强弱顺序10%DCD>1%DMPP>5%AM(这里的数值代表硝化抑制剂的施入量

  4. 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


  5. 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.)

  6. Transformation of Applied Phosphorus in a Calcareous Fluvisol

    Institute of Scientific and Technical Information of China (English)

    TUSHU-XIN; GUOZHI-FEN; 等

    1993-01-01

    A new inorganic phosphorus(IP) fractionation scheme developed by Jiang and Gu wasused in an incubation experiment to investigate the transformation of applied P in a calcareous fluvisol.The results show that after addition of common superphosphate (CSP),the Ca2-P in the soil decreased gradually and transformed largely to the less available Fe-P,Al-P and Ca8-P,rather than to the unavailable forms of Ca10-P and O-P.The different IP fractions ranked in the following order with respect to the increment by addition of CSP after 120 days of incubation:Fe-P>Al-P>Ca8-P>Ca2-P.After addition of pig manure,the content of Ca2-P in the soil increased rapidly at first and then decreased slowly,and the amount of different IP fractions accumulated after 120 days of incubation ranked in the following order:Ca2-P>Fe-P>Ca8-P>Al-P.Evidently,the variation in content of Ca2-P and the order of increase in different IP fractions in incubation induced by application of pig manure were quite different from that of CSP.The increase in IP fractions in the incubation of broad bean green manure (BBGM) for 120 days was in the rank of Fe-P>Ca2-P>Ca8-P;but because organic phosphorus(OP)of BBGM degraded relatively slowly,the increment in IP fractions was lower than that of pig manure.Wheat straw was difficult to mineralize and induced a strong biological fixation of soil P,resulting in a decrease of the content of Ca2-P,even Ca8-P,Fe-P and Al-P.

  7. The sterols of calcareous sponges (Calcarea, Porifera).

    Science.gov (United States)

    Hagemann, Andrea; Voigt, Oliver; Wörheide, Gert; Thiel, Volker

    2008-11-01

    Sponges are sessile suspension-feeding organisms whose internal phylogenetic relationships are still the subject of intense debate. Sterols may have the potential to be used as independent markers to test phylogenetic hypotheses. Twenty representative specimens of calcareous sponges (class Calcarea, phylum Porifera) with a broad coverage within both subclasses Calcinea and Calcaronea were analysed for their sterol content. Two major pseudohomologous series were found, accompanied by some additional sterols. The first series encompassing conventional C(27) to C(29)Delta(5,7,22) sterols represented the major sterols, with ergosterol (ergosta-5,7,22-trien-3beta-ol, C(28)Delta(5,7,22)) being most prominent in many species. The second series consisted of unusual C(27) to C(29)Delta(5,7,9(11),22) sterols. Cholesterol occurred sporadically, mostly in trace amounts. The sterol patterns did not resolve intraclass phylogenetic relationships, namely the distinction between the subclasses, Calcinea and Calcaronea. This pointed towards major calcarean lipid traits being established prior to the separation of subclasses. Furthermore, calcarean sterol patterns clearly differ from those found in Hexactinellida, whereas partial overlap occurred with some Demospongiae. Hence, sterols only partly reflect the phylogenetic separation of Calcarea from both of the other poriferan classes that was proposed by recent molecular work and fatty acid analyses.

  8. 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.

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

    Directory of Open Access Journals (Sweden)

    S. RUSINA

    2003-01-01

    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.

  10. Speciation And Distribution Of Phosphorus In A Fertilized Soil: A Synchrotron-Based Investigation

    Science.gov (United States)

    Phosphorus availability is often a limiting factor for crop production around the world. The efficiency of P fertilizers in calcareous soils is limited by reactions that decrease P availability; however, fluid fertilizers have recently been shown, in highly calcareous soils of s...

  11. Uranium geochemistry in a calcareous peat: mineral-organic-microorganisms interactions and implications on uranium mobility in a contaminated soil; Geochimie de l'uranium dans une tourbe calcaire: interactions mineral - organique - micro-organismes et implications sur la mobilite de l'uranium dans un sol contamine

    Energy Technology Data Exchange (ETDEWEB)

    Phrommavanh, V.; Descostes, M.; L' Orphelin, J.M.; Beaucaire, C. [CEA Saclay, DEN/DPC/SECR/Laboratoire de Mesure et Modelisation de la Migration des Radionucleides, 91 - Gif-sur-Yvette (France); Gaudet, J.P. [LTHE/ENSHMG, 38 - St Martin d' Heres (France)

    2009-07-01

    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

  12. Interaction of NPK Fertilizers During Their Transformation in Soils:I.Dynamic Changes of Soil pH

    Institute of Scientific and Technical Information of China (English)

    WANG HUOYAN; ZHOU JIANMIN; CHEN XIAOQIN; LI SHOUTIAN; DU CHANGWEN; DONG CAIXIA

    2003-01-01

    Dynamic changes of soil pH as influenced by ammonium sulfate (AS), monocalcium phosphate (MCP),potassium chloride (KCl) and their interaction in soils were evaluated in incubation experiments. Applyingthese fertilizers significantly reduced soil pH values in all cases and followed sequences of AS > MCP >KCl, MCP > KCl > AS and KCl > AS > MCP for the paddy, calcareous and red soils, respectively. TheAS-induced reduction of pH in the three soils followed the sequence of red soil > paddy soilcalcareous soil,while in MCP and KCl systems the reduction of pH followed the sequences of calcareous soil > paddy soil >red soil and red soilcalcareous soil > paddy soil, respectively. The interactions of the NPK fertilizers on pHwere significant. MCP plus KCl or MCP plus AS reduced pH values more than the fertilizers applied solelyin the paddy soil, but AS partly counteracted the effect of MCP on pH in the 1 d sample of the calcareoussoil. The effect of MCP on pH was trivial when MCP was applied in combination with KCl or AS in the redsoil. When applied in combination with AS, KCl did not affect soil pH initially, but suppressed the reductionof pH at the later incubation stage, which was related to inhibition of nitrification by KCl in the soils.

  13. Malacofauna of Holocene freshwater calcareous deposits of Lithuania

    Science.gov (United States)

    Sanko, Aleksander; Vainorius, Julius; Melešytė, Monika

    2010-12-01

    The malacofauna of freshwater calcareous deposits of Lithuania was studied. Sections of the Mūšos Tyrelis and Pabaliai peatbogs near the town of Šiauliai, as well as Dubičiai section (three sites) in SE Lithuania and Dūkštos in Central Lithuania were investigated. Freshwater calcareous deposits are attributed to three groups of facies - lacustrine, valley-hollow-peatbog and terrestrial. Each group of facies consists of sub-facies (freshwater lime, "gazha" (limno-calcite), peat-tufa, calcareous tufa, "mada") varying the formation conditions, composition and other characteristics. The mollusc fauna in the lacustrine facies group (Mūšos Tyrelis and Pabaliai sections) is represented by lacustrine species containing euryecological freshwater molluscs. Terrestrial and rheophilous species are rare or absent in the lacustrine group. Deposits of valley-hollow-peatbog facies contain shells of euryecological freshwater and lacustrine molluscs together with rheophyl shells, sometimes with abundant terrestrial shells, as was observed in the Dubičiai-4 section. A characteristic feature of the terrestrial facies group deposits is the occurrence of solely terrestrial mollusc shells (Dūkštos section).

  14. A first paleomagnetic and rock magnetic investigation of calcareous nodules from the Chinese Loess Plateau

    Science.gov (United States)

    Yang, T.; Hyodo, M.; Yang, Z.; Sun, Z.

    2005-01-01

    A detailed paleomagnetic and rock magnetic investigation was carried out on calcareous nodule layers embed-ded in the loess-paleosol sequences near Baoji city, southern Chinese Loess Plateau. The anisotropy of low-field magnetic susceptibility confirms that calcareous nodules retain the primary sedimentary fabric of original de-posits. Rock magnetic properties demonstrate that calcareous nodules have the same mineralogy and grain sizes as loess-paleosol deposits. Characteristic remanent magnetizations of calcareous nodules have directions consis-tent with those of adjacent loess and paleosol deposits. The Punaruu event, previously found from loess deposits in the upper part of loess unit L13 in Weinan, southern Chinese Loess Plateau, is observed at the corresponding stratigraphic level in the calcareous nodule layer. These observations indicate that the calcareous nodule layers preserve primary remanent magnetizations of original deposits before calcification, and that they can contribute to paleomagnetic studies in the Chinese Loess Plateau.

  15. Size fraction characterization of highly-calcareous fly ash

    Energy Technology Data Exchange (ETDEWEB)

    Itskos, Grigorios; Koukouzas, Nikolaos [Institute for Solid Fuels Technology and Applications, Centre for Research and Technology Hellas, 357-359 Mesogeion Avenue, GR-152 31, Halandri, Athens (Greece); Itskos, Socrates [Department of Chemical Technology and the Environment, Steam Electric Station of Amynteon-Filotas, Public Power Corporation of Greece, GR-532 00, Amynteon (Greece)

    2010-11-15

    The chemical and mineralogical composition of lignite fly ash (FA) varies as a function of the prevalent conditions in both the processes of power production and lignite mining. The differentiation of the qualitative and quantitative composition of the highly-calcareous lignite fly ash, as a function of its particle size distribution, is verified in this paper. According to the results of the conducted research, a fine-grained fraction of considerable amount presents properties that obstruct the sustainable exploitation of calcareous lignite fly ash in cement industry applications. On the other hand, the same grain fraction (because of its hydraulic properties) can be utilized in other sort of applications, based on different criteria, i.e. in road constructions. The coarse-grained fraction (which reflects a low proportion to the total fly ash output) presents the same undesired characteristics as well. Rather, the intermediate grain fraction (75-150 {mu}m) presents the highly desirable properties when fly ash is utilized as a pozzolanic additive. In addition, the mechanism of the formation of the intermediate grain fraction strongly prevents the factors that cause the variation of fly ash-quality. It is therefore the optimum part of the whole amount of lignite FA, to be utilized as additive in cement manufacturing. The outcomes of this paper will hopefully contribute towards the crucial goal of the expansion of the utilization of calcareous lignite fly ash by proposing a more effective way of using this material, basically by taking advantage of its fundamental chemical and mineralogical properties. (author)

  16. Effects of roads on adjacent plant community composition and ecosystem function: An example from three calcareous ecosystems.

    Science.gov (United States)

    Lee, Mark A; Davies, Linda; Power, Sally A

    2012-04-01

    Roads and exhaust emissions can affect plant communities directly, for example via direct foliar uptake of exhaust products, or indirectly via changes to soil biogeochemistry and hydrology. A transect study adjacent to roads of different traffic densities was carried out at three species-rich calcareous grasslands in south eastern England. Measured annual NO(2) concentrations and modelled NH(3) concentrations increased towards the roads and with higher traffic densities, and there was evidence of increased soil moisture, pH and heavy metal concentrations at roadsides. Increases in the abundance of nitrogen (N) tolerant species and grasses at roadsides were associated with N enrichment from vehicle exhausts at two of the sites. In contrast plant species richness, the abundance of forb and moss species declined at roadside locations. As vehicle usage spreads across the world, it is increasingly important to understand the effects of road traffic on adjacent ecosystems to inform traffic and conservation management policies.

  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 an

  18. Cylinders and seances : Elise van Calcar and the spirit of Froebel

    NARCIS (Netherlands)

    Bakker, Nelleke

    2013-01-01

    This essay discusses the life and work of Elise van Calcar (18221904), a writer and maternal feminist who introduced Froebel's kindergarten in the Netherlands. Van Calcar also was the leader of a Christian branch of spiritualism. The focus is pointed at parallels between her reading of Froebel and o

  19. Cylinders and Seances: Elise van Calcar and the Spirit of Froebel

    Science.gov (United States)

    Bakker, Nelleke

    2013-01-01

    This essay discusses the life and work of Elise van Calcar (1822-1904), a writer and maternal feminist who introduced Froebel's kindergarten in the Netherlands. Van Calcar also was the leader of a Christian branch of spiritualism. The focus is pointed at parallels between her reading of Froebel and of "messages" from spirits in the…

  20. Computational Visual Stress Level Analysis of Calcareous Algae Exposed to Sedimentation

    Science.gov (United States)

    Nilssen, Ingunn; Eide, Ingvar; de Oliveira Figueiredo, Marcia Abreu; de Souza Tâmega, Frederico Tapajós; Nattkemper, Tim W.

    2016-01-01

    This paper presents a machine learning based approach for analyses of photos collected from laboratory experiments conducted to assess the potential impact of water-based drill cuttings on deep-water rhodolith-forming calcareous algae. This pilot study uses imaging technology to quantify and monitor the stress levels of the calcareous algae Mesophyllum engelhartii (Foslie) Adey caused by various degrees of light exposure, flow intensity and amount of sediment. A machine learning based algorithm was applied to assess the temporal variation of the calcareous algae size (∼ mass) and color automatically. Measured size and color were correlated to the photosynthetic efficiency (maximum quantum yield of charge separation in photosystem II, ΦPSIImax) and degree of sediment coverage using multivariate regression. The multivariate regression showed correlations between time and calcareous algae sizes, as well as correlations between fluorescence and calcareous algae colors. PMID:27285611

  1. The Micro-mechanism Involved and Wollastonite Signature in the Calcareous Precipitates of Marine Isolates.

    Science.gov (United States)

    Sarayu, K; Iyer, Nagesh R; Annaselvi, M; Ramachandra Murthy, A

    2016-03-01

    Micro-mechanical studies connecting the influence of extrinsic factors over intrinsic factors on 30 calcareous isolates obtained from marine sediment biofilms of the Bay of Bengal (Indian Ocean) revealed that the fate of calcareous crystal precipitation is highly dependent on factors like extracellular polysaccharides (EPS), organic carbon and nutrition. Further studies exemplified that EPS and the organic carbon secreted by the isolates controlled the dissemination of the calcareous crystals precipitated. From the study, it is evident that an EPS concentration of 7-15 mg l(-1) was found to enhance the dissemination of the calcareous crystals. Atomic force micrographs explain the nucleation behaviour and morphology of the calcareous crystals precipitated. X-ray diffraction (XRD) and energy-dispersive X-ray spectroscopy (EDAX) showed that the crystals were mainly composed of calcite and partially wollastonite.

  2. Isotopic composition of sulfate accumulations, Northern Calcareous Alps, Austria

    Science.gov (United States)

    Bojar, Ana-Voica; Halas, Stanislaw; Bojar, Hans-Peter; Trembaczowski, Andrzej

    2015-04-01

    The Eastern Alps are characterised by the presence of three main tectonic units, such as the Lower, Middle and Upper Austroalpine, which overlie the Penninicum (Tollmann, 1977). The Upper Austroalpine unit consists of the Northern Calcareous Alps (NCA) overlying the Greywacke zone and corresponding to the Graz Paleozoic, Murau Paleozoic and the Gurktal Nappe. Evaporitic rocks are lacking in the later ones. The Northern Calcareous Alps are a detached fold and thrust belt. The sedimentation started in the Late Carboniferous or Early Permian, the age of the youngest sediments being Eocene. The NCA are divided into the Bajuvaric, Tirolic and Juvavic nappe complexes. The evaporitic Haselgebirge Formation occurs in connection with the Juvavic nappe complex at the base of the Tirolic units (Leitner et al., 2013). The Haselgebirge Formation consists mainly of salt, shales, gypsum and anhydrite and includes the oldest sediments of the NCA. The age of the Haselgebirge Formation, established by using spors and geochronological data, is Permian to Lower Triassic. For the Northern Calcareous Alps, the mineralogy of sulphate accumulations consists mainly of gypsum and anhydrite and subordonates of carbonates. The carbonates as magnesite, dolomite and calcite can be found either as singular crystals or as small accumulations within the hosting gypsum. Sulfides (sphalerite, galena, pyrite), sulfarsenides (enargite, baumhauerite) and native sulphur enrichments are known from several deposits (Kirchner, 1987; Postl, 1990). The investigated samples were selected from various gypsum and halite rich deposits of the Northern Calcareous Alps. A total of over 20 samples were investigated, and both oxygen and sulfur isotopic composition were determined for anhydrite, gyps, polyhalite, blödite and langbeinite. The sulfur isotopic values vary between 10.1 to 14 ‰ (CDT), with three values higher than 14 ‰. The Oxygen isotopic values show a range from 9 to 23 ‰ (SMOW). The sulfur

  3. 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.

    the one formed in the dark. The light-enhanced deposit also possessed better scale properties, as suggested by X-ray analysis and electrochemical measurements. Sunlight enhancement of calcareous deposition looked all the more conspicuous when day and night...

  4. 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.

    Fungi were isolated from calcareous animal shells at 100-860 m depth in the Bay of Bengal. All the species isolated were terrestrial ones, Aspergillus restrictus Smith being the most common. The behaviour of this fungus at various hydrostatic...

  5. 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...

  6. The calcar femorale: a tale of historical neglect.

    Science.gov (United States)

    Newell, R L

    1997-01-01

    The term calcar femorale (originally referring to a bony spur projecting into the cancellous tissue of the base of the femoral neck) differs from most anatomical terms in that it has developed separate meanings in different areas of use. In particular, its present meaning for most orthopedic surgeons differs from its classical anatomical significance. This work shows that the classical, "textbook" anatomical interpretation-usually attributed to Merkel (1874, cited by Harty, 1957, J. Bone Joint Surg. [Am.] 39:625-630)-is not entirely correct, being based on an incomplete appreciation of the true nature of the three-dimensional structure of the upper end of the femur. Though Humphry (1858, A Treatise on the Human Skeleton, Cambridge, England: Macmillan) was aware of the importance of the third dimension, it was the largely neglected work of Dixon (1910, J. Anat. Physiol., 44:223-230), itself published to draw attention to the ideas of Krause (1909, in Bardeleben's Handbuch der Anatomie des Menschen, Jena: Gustav Fischer), which indicated the true nature of the calcar femorale and the limitations of Merkel's view. Dixon's work has been developed and consolidated by others such as Garden (1961, J. Bone Joint Surg. [Br.] 43:576-589), who was apparently unaware of Dixon, just as Dixon himself appears to have been unaware of the work of Bigelow (1875, published in Bigelow, 1900, The Mechanisms of Dislocations and Fracture of the Hip, Boston: Little, Brown), which pre-empted one of his major concepts. Even earlier work by Bigelow (1869, published in Bigelow; 1900, The Mechanisms of Dislocations and Fracture of the Hip, Boston: Little, Brown) appears to have pre-empted that of Merkel. The adoption of the three-dimensional, "Dixon concept" of the bony anatomy of the upper end of the femur leads to an entirely different set of structural engineering analogies from those two-dimensional ones which have become commonplace since the work of Ward (1838, cited by Garden, 1961, J

  7. 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.

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

    Science.gov (United States)

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

    2016-10-01

    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.

  9. The fatty acids of calcareous sponges (Calcarea, Porifera).

    Science.gov (United States)

    Schreiber, Andrea; Wörheide, Gert; Thiel, Volker

    2006-09-01

    Twenty-nine specimens of calcareous sponges (Class Calcarea, Phylum Porifera), covering thirteen representative species of the families Soleneiscidae, Leucaltidae, Levinellidae, Leucettidae, Clathrinidae, Sycettidae, Grantiidae, Jenkinidae, and Heteropiidae were analysed for their fatty acids. The fatty acids of Calcarea generally comprise saturated and monounsaturated linear (n-), and terminally methylated (iso-, anteiso-) C(14)-C(20) homologues. Furthermore, polyunsaturated C(22) fatty acids and the isoprenoic 4,8,12-trimethyltridecanoic acid were found. The most prominent compounds are n-C(16), iso-C(17), iso-C(18), n-C(18), n-C(20). In addition, a high abundance of the exotic 16-methyloctadecanoic acid (anteiso-C(19)) appears to be a characteristic trait of Calcarea. Long-chain 'demospongic acids', typically found in Demospongiae and Hexactinellida, are absent in Calcarea. The completely different strategy of calcarean fatty acid synthesis supports their phylogenetic distinctiveness from a common Demospongiae/Hexactinellida taxon. Both intraspecific and intraclass patterns of Calcarea showed great similarity, suggesting a conserved fatty acid composition that already existed in the last common ancestor of Calcinea and Calcaronea, i.e. before subclasses diverged.

  10. Rock composition and origin of the Duwi Formation calcareous rocks, Upper Egypt

    Institute of Scientific and Technical Information of China (English)

    Baioumy H.M.; Attia A.M.; Boulis S.N.; Hassan M.S.; Helmy M.E.

    2005-01-01

    Upper Cretaceous phosphorite beds of the Duwi Formation, Upper Egypt, are intercalated with limestone, sandy limestone, marl, calcareous shales, and calcareous sandstone. Calcareous intercalations were subjected to field and detailed petrographic, mineralogical and geochemical investigations in order to constrain their rock composition and origin.Mineralogically, dolomite, calcite, quartz, francolite and feldspars are the non-clay minerals. Smectite, kaolinite and illite represent the clay minerals. Major and trace elements can be classified as the detrital and carbonate fractions based on their sources. The detrital fraction includes the elements that are derived from detrital sources, mainly clay minerals and quartz, such as Si, Al, Fe, Ti, K, Ba, V, Ni, Co, Cr, Zn, Cu, Zr, and Mo. The carbonate fraction includes the elements that are derived from carbonates, maily calcite and dolomite, such as Ca, Mg and Sr. Dolomite occurs as being dense, uniform, mosaic, very fine-to-fine, non-ferroan, and non-stoichiometrical suggesting its early diagenetic formation in a near-shore oxidizing shallow marine environment. The close association and positive correlation between dolomite and smectite indicates the role of clay minerals in the formation of dolomite as a source of Mg 2+-rich solutions.Calcareous rocks were deposited in marine, oxidizing and weakly alkaline conditions, marking a semi-arid climatic period. The calcareous/argillaceous alternations are due to oscillations in clay/carbonate ratio.

  11. [Effects of parent rock and land use pattern on soil fertility in Karst region of Northwest Guangxi].

    Science.gov (United States)

    Yang, Shan; He, Xun-Yang; Su, Yi-Rong; Zhang, Wei; Wang, Ke-Lin

    2010-06-01

    Taking the soils developed on limestone and sandstone and with typical land use patterns in Karst region of Northwest Guangxi as test objects, this paper studied their soil fertility under effects of parent rock and land use pattern. A total of eleven soil fertility variables were selected for factor analysis, and the component score for each sampling site was assessed by using principal component analysis (PCA) sequencing and clustering diagram. The factor analysis indicated that the eleven variables could be reduced to four components, i.e., overall soil fertility, soil pH and total phosphorus, soil available phosphorus, and soil total potassium. The PCA sequencing and clustering analysis showed that the overall soil fertility was mainly affected by land use pattern, being the highest in abandoned farmland. Soil pH and total phosphorus content were mainly affected by parent rock. The pH value and total phosphorus content in the red soil developed on sandstone were much lower than those in the calcareous soil developed on limestone. Soil available phosphorus and total potassium contents were significantly affected by fertilization. The available phosphorus and total potassium contents in Karst calcareous soil and red soil were lower than the average level of China soils. Therefore, the Karst calcareous soil should be fertilized with ammonium nitrogen fertilizer to improve its phosphorus availability, while the Karst red soil should be amended with lime to increase its available phosphorus content. In addition, potassium fertilizer should be applied to the two soil types to improve their soil fertility.

  12. Collembolan species diversity of calcareous canyons in the Republic of Moldova.

    Science.gov (United States)

    Buşmachiu, Galina; Bedos, Anne; Deharveng, Louis

    2015-01-01

    The study of collembolan communities from the Vîşcăuți canyon in Moldova revealed 63 species belonging to 41 genera and 12 families, including four species new for the fauna of the Republic of Moldova. A checklist of collembolan species identified in the five calcareous canyons sampled so far in Moldova is included, with data on habitats, life form, occurrence and comments of distribution of most remarkable species. Of the 98 recognized species of these calcareous canyons, only 38 were shared by Vîşcăuți and the other canyons. The richness of calcareous habitats together with the high heterogeneity in faunal composition suggests that further significant increase in the species richness of the region may be expected.

  13. Interaction of NPK Fertilizers During Their Transformation in Soils:III.Transformations of Monocalcium Phosphate

    Institute of Scientific and Technical Information of China (English)

    WANG Huo-Yan; ZHOU Jian-Min; CHEN Xiao-Qin; DU Chang-Wen

    2004-01-01

    Interactions of N, P and K fertilizers in soil-plant systems are widely recognized. This study focused on the transformations of monocalcium phosphate (Ca(H2PO4)2) (MCP) with co-application of ammonium and potassium fertilizers in three different soils. The results showed that after i d incubation a large portion of the MCP applied in the paddy,calcareous and red soils became the water-insoluble form and the recoveries of P applied as Olsen P varied greatly in these three soils. Application of ammonium sulfate ((NH4)2SO4) (AS) or potassium chloride (KC1) reduced WSP significantly in the soils with AS more effective than KC1 in the calcareous soil, while the reverse occurred in the red soil. Meanwhile, in the paddy soil, co-application of the two fertilizers reduced WSP more than when the fertilizers were applied individually. The co-application of AS with MCP in the paddy and calcareous soils significantly reduced Olsen P, but the opposite occurred in the red soil. The experiment on the effect of different accompanying anions showed that the ammonium fertilizers (PNC1 and PNS) reduced WSP more effectively than the corresponding potassium fertilizers (PKC1 and PKS) in the calcareous soil due to the difference of the cations, whereas in the red soil, the chlorides reduced WSP more effectively than the sulfates. Overall, co-application of ammonium or potassium fertilizers with MCP significantly decreased availability of P from MCP during its transformation in soils, especially when MCP was applied in combination with ammonium in the calcareous soil.

  14. Influence of Sweet Crude Oil on Nucleation and Corrosion Resistance of Calcareous Deposits

    Science.gov (United States)

    Hoseinieh, S. M.; Shahrabi, T.; Ramezanzadeh, B.; Farrokhi Rad, M.

    2016-11-01

    The influence of sweet crude oil on calcareous scale deposition under cathodic protection of carbon steel in artificial seawater was investigated using chronoamperometry, electrochemical impedance spectroscopy, scanning electron microscope/energy-dispersive spectroscopy, x-ray diffraction and Raman spectroscopy. In the presence of crude oil, calcareous deposit formation is influenced in terms of both kinetic and nucleation mostly in high volume concentrations. It is indicated that the CaCO3 deposition is hindered by absorption of active surface compounds present in oil on to the surface mainly due to strong covalent bonding of aromatic compounds.

  15. A landscape approach for the study of calcareous grassland plant communities

    Directory of Open Access Journals (Sweden)

    Mahy G.

    2005-01-01

    Full Text Available Habitat fragmentation is the principal threat on biodiversity in semi-natural habitats. The consequences of fragmentation for biodiversity may be studied within the framework of landscape ecology. In this context, three paradigms have generated hypotheses that need to be tested in field situations: the insular biogeography paradigm, the small population paradigm and the metapopulation paradigm. Examination of two case studies showed that Belgian calcareous grasslands have undergone a drastic fragmentation process during the last century. Size of patches is shown to be the most important determinant for species richness, species composition and probability of presence of characteristic species in a fragmented system of calcareous grasslands in Calestienne, Belgium.

  16. 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.

  17. 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.

  18. 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...

  19. 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…

  20. 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.

  1. EDTA retention and emissions from remediated soil.

    Science.gov (United States)

    Jez, Erika; Lestan, Domen

    2016-05-01

    EDTA-based remediation is reaching maturity but little information is available on the state of chelant in remediated soil. EDTA soil retention was examined after extracting 20 soil samples from Pb contaminated areas in Slovenia, Austria, Czech Republic and USA with 120 mM kg(-1) Na2H2EDTA, CaNa2EDTA and H4EDTA for 2 and 24 h. On average, 73% of Pb was removed from acidic and 71% from calcareous soils (24 h extractions). On average, 15% and up to 64% of applied EDTA was after remediation retained in acidic soils. Much less; in average 1% and up to the 22% of EDTA was retained in calcareous soils. The secondary emissions of EDTA retained in selected remediated soil increased with the acidity of the media: the TCLP (Toxicity Characteristic Leaching Procedure) solution (average pH end point 3.6) released up to 36% of EDTA applied in the soil (28.1 mmol kg(-1)). Extraction with deionised water (pH > 6.0) did not produce measurable EDTA emissions. Exposing soil to model abiotic (thawing/freezing cycles) and biotic (ingestion by earthworms Lumbricus rubellus) ageing factors did not induce additional secondary emissions of EDTA retained in remediated soil.

  2. Réparation des pieux battus dans les sables carbonatés Repair of Driven Piles in Calcareous Formations

    Directory of Open Access Journals (Sweden)

    Nauroy J. F.

    2006-11-01

    Full Text Available Les formations carbonatées rencontrées en de nombreuses zones d'activités pétrolières en mer posent de difficiles problèmes de dimensionnement et de mise en place des pieux. Sur plusieurs sites de sable carbonaté, la capacité portante des pieux battus se révèle beaucoup plus faible que prévu et des techniques de réparation doivent être étudiées. Dans ce contexte, l'ARGEMA (Association de Recherche en Géotechnique Marine, groupement français d'organismes de recherche, de compagnies pétrolières et de contracteurs offshore, a expérimenté une réparation d'un pieu expérimental de 30 cm de diamètre et 23 m de long battu dans un sable carbonaté. Le frottement latéral de ce pieu mobilisé juste après battage était très faible. La réparation a consisté à injecter du coulis de ciment à partir d'un forage situé à 40 cm du pieu. Cet article décrit les procédures et les caractéristiques des injections réalisées et leurs conséquences sur la capacité portante du pieu. Le frottement entre le pieu et le terrain s'accroît avec le volume de ciment injecté; les valeurs maximales obtenues sont du même ordre de grandeur que celles observées avec un pieu foré-cimenté. The calcareous formations encountered in many zones of offshore petroleum activity raise difficult problems for designing and installing foundation piles. On several sites with calcareous sands, the bearing capacity of driven piles proves to be much less than had been planned, and repair techniques have to be examined. Within this context, ARGEMA (Association de Recherche en Géotechnique Marine, a french group of research organizations, oil companies and offshore contractors, has tested a repair of an experimental pile 30 cm in diameter and 23 m long driven into a calcareous sand. The skin friction of this pile, mobilized just after driving, was found to be very low. The repair-job consisted in injecting grout from a drilled borehole located at some tens

  3. New observations on Permocalculus gosaviensis SCHLAGINTWEIT, 1991 (calcareous alga from the Upper Cretaceous of the Northern Calcareous Alps (Gosau Group, Austria

    Directory of Open Access Journals (Sweden)

    Felix Schlagintweit

    2010-08-01

    Full Text Available New thin-sections from the Upper Cretaceous Gosau Group of Brandenberg, Tyrol, Austria, yielded well-preserved specimens of the calcareous alga Permocalculus gosaviensis Schlagintweit. Microfacies are foraminiferal-algal wackestones; stratigraphy is Upper Turonian (?Lower Coniacian. It is shown that the original description was based on oblique sections leading to the incorrect assumption of a piriform segment morphology. Instead, P. gosaviensis is a representative of Permocalculus of the group with constrictions/swellings along the segments (waxing-and-waning type. Permocalculus nikolapantici Radoičić from the Upper Turonian of Serbia is considered a junior synonym of Permocalculus gosaviensis Schlagintweit.

  4. Calcareous scales formed by cathodic protection—an assessment of characteristics and kinetics

    Science.gov (United States)

    Neville, Anne; Morizot, Arnaud P.

    2002-09-01

    An electrochemical technique using the assessment of the rate of oxygen reduction at a rotating disk electrode has been used in conjunction with surface analysis by X-ray photoelectron spectroscopy to study the first layer formation of calcareous deposits under cathodic protection in various solutions. The study has shown that the electrochemical technique is an effective means of monitoring scale formation and that the existing models which predict scale formation by a basal layer of Mg(OH) 2 followed by CaCO 3 are over-simplified. The advantages of using an integrated approach of electrochemical analysis and a surface sensitive analysis technique in characterising the initial scale as a function of the solution composition are presented and discussed and revised models describing the temporal development of calcareous layers in saline solutions are suggested.

  5. CALCAREOUS NANNOFOSSIL BIOSTRATIGRAPHY OF PALEOCENE TO MIDDLE EOCENE SUCCESSIONS (TERTIARY FLYSCH AUCTT. OF THE NORTHERN APENNINES

    Directory of Open Access Journals (Sweden)

    RITA CATANZARITI

    2015-11-01

    Full Text Available An accurate biostratigraphic study of the Paleocene-middle Eocene calcareous nannofossils was performed on the turbiditic successions that characterize the Northern Apennines Mt. Caio, Farini d’Olmo, Mt. Sporno and Mt. Penice Units, belonging to the “Tertiary Flysch Auctt.” and referable to the External Ligurides. This geologic complex accumulated in a link key area, located between the oceanic Ligure-Piedmontese domain and the Adria continental margin. The reference biostratigraphic scheme used in the study is the recently published calcareous nannofossil biozonation proposed for the Paleogene by Agnini et al. (2014. The obtained biostratigraphic and chronostratigraphic data suggest that further investigation is needed to clarify the tectono-sedimentary evolution and to unravel the complex architecture of the External Ligurides.

  6. 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

    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......Chalk develops as a result of diagenesis of pelagic calcareous ooze. In a newly deposited ooze sediment, porosity ranges from 60% to 80% but porosity reduces with burial. We studied how different porosity reduction mechanisms change the strength of these deep sea carbonate-rich sediments and effect...... 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...

  7. Effect of rotational shepherding on demographic and genetic connectivity of calcareous grassland plants.

    Science.gov (United States)

    Rico, Yessica; Boehmer, Hans Juergen; Wagner, Helene H

    2014-04-01

    Response to habitat fragmentation may not be generalized among species, in particular for plant communities with a variety of dispersal traits. Calcareous grasslands are one of the most species-rich habitats in Central Europe, but abandonment of traditional management has caused a dramatic decline of calcareous grassland species. In the Southern Franconian Alb in Germany, reintroduction of rotational shepherding in previously abandoned grasslands has restored species diversity, and it has been suggested that sheep support seed dispersal among grasslands. We tested the effect of rotational shepherding on demographic and genetic connectivity of calcareous grassland specialist plants and whether the response of plant populations to shepherding was limited to species dispersed by animals (zoochory). Specifically, we tested competing dispersal models and source and focal patch properties to explain landscape connectivity with patch-occupancy data of 31 species. We fitted the same connectivity models to patch occupancy and nuclear microsatellite data for the herb Dianthus carthusianorum (Carthusian pink). For 27 species, patch connectivity was explained by dispersal by rotational shepherding regardless of adaptations to zoochory, whereas population size (16% species) and patch area (0% species) of source patches were not important predictors of patch occupancy in most species. [Correction made after online publication, February 25, 2014: Population size and patch area percentages were mistakenly inverted, and have now been fixed.] Microsite diversity of focal patches significantly increased the model variance explained by patch occupancy in 90% of the species. For D. carthusianorum, patch connectivity through rotational shepherding explained both patch occupancy and population genetic diversity. Our results suggest shepherding provides dispersal for multiple plant species regardless of their dispersal adaptations and thus offers a useful approach to restore plant

  8. 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.

  9. 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.

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

    OpenAIRE

    Rusina, S.

    2003-01-01

    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 associa...

  11. 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.

  12. The calcar screw in angular stable plate fixation of proximal humeral fractures - a case study

    Directory of Open Access Journals (Sweden)

    Simmen Hans-Peter

    2011-09-01

    Full Text Available Abstract Background With new minimally-invasive approaches for angular stable plate fixation of proximal humeral fractures, the need for the placement of oblique inferomedial screws ('calcar screw' has increasingly been discussed. The purpose of this study was to investigate the influence of calcar screws on secondary loss of reduction and on the occurrence of complications. Methods Patients with a proximal humeral fracture who underwent angular stable plate fixation between 01/2007 and 07/2009 were included. On AP views of the shoulder, the difference in height between humeral head and the proximal end of the plate were determined postoperatively and at follow-up. Additionally, the occurrence of complications was documented. Patients with calcar screws were assigned to group C+, patients without to group C-. Results Follow-up was possible in 60 patients (C+ 6.7 ± 5.6 M/C- 5.0 ± 2.8 M. Humeral head necrosis occurred in 6 (C+, 15.4% and 3 (C-, 14.3% cases. Cut-out of the proximal screws was observed in 3 (C+, 7.7% and 1 (C-, 4.8% cases. In each group, 1 patient showed delayed union. Implant failure or lesions of the axillary nerve were not observed. In 44 patients, true AP and Neer views were available to measure the head-plate distance. There was a significant loss of reduction in group C- (2.56 ± 2.65 mm compared to C+ (0.77 ± 1.44 mm; p = 0.01. Conclusions The placement of calcar screws in the angular stable plate fixation of proximal humeral fractures is associated with less secondary loss of reduction by providing inferomedial support. An increased risk for complications could not be shown.

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

    OpenAIRE

    S. RUSINA

    2003-01-01

    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 w...

  14. A landscape approach for the study of calcareous grassland plant communities

    OpenAIRE

    Mahy G.; Bisteau E.

    2005-01-01

    Habitat fragmentation is the principal threat on biodiversity in semi-natural habitats. The consequences of fragmentation for biodiversity may be studied within the framework of landscape ecology. In this context, three paradigms have generated hypotheses that need to be tested in field situations: the insular biogeography paradigm, the small population paradigm and the metapopulation paradigm. Examination of two case studies showed that Belgian calcareous grasslands have undergone a dras...

  15. Soil disturbance as a grassland restoration measure

    DEFF Research Database (Denmark)

    Schnoor, Tim; Bruun, Hans Henrik; Olsson, Pål Axel

    2015-01-01

    Soil disturbance is recognized as an important driver of biodiversity in dry grasslands, and can therefore be implemented as a restoration measure. However, because community re-assembly following disturbance includes stochastic processes, a focus only on species richness or establishment success...... target. Species richness and functional diversity both increased in response to soil disturbance, and rotavation, but not ploughing, had a persistent positive effect on the occurrence of specialist species of calcareous sandy grassland. However, no type of soil disturbance caused the plant species...

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

    Directory of Open Access Journals (Sweden)

    Wojciech Bąba

    2011-04-01

    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.

  17. Diversity, distribution, and new phylogenetic information of calcareous dinoflagellates from the China Sea

    Institute of Scientific and Technical Information of China (English)

    Hai-Feng GU; Zhao-He LUO; Yan WANG; Dong-Zhao LAN

    2011-01-01

    Calcareous dinoflagellates have been recorded from subarctic to tropical areas, inhabiting both neritic and oceanic regions. In the present study we analyse 12 sediment samples from the China Sea to establish the existence of calcareous dinoflagellates in this area. A total of 11 calcareous dinoflagellate species were recorded,among them, three genera (Calciodinellum, Leonella, Posoniella) and seven species (Calciodinellum albatrosianum,C. levantinum, C. operosum, Leonella granifera, Posoniella tricarinelloides, Scrippsiella irregularis, and S. regalis)were reported from the China Sea for the first time. Cysts of S. irregularis and S. precaria are identical, with a mesoepicystal archeopyle, representing the loss of 2-4' and 1-3a paraplates; however, their thecal plates vary slightly and differ from each other in 78 positions of the internal transcribed spacer sequence. Scrippsiella trochoidea is dominant in coastal areas, whereas Calciodinellum albatrosianum is the most abundant offshore. Scrippsiella irregularis is distributed widely along the coast of China, whereas S. precaria is recorded only in northern China.Leonella granifera is the second most abundant species offshore, comprising 15-40% of the cyst assemblage.

  18. Soil Structure and Saturated Hydraulic Conductivity

    Science.gov (United States)

    Houskova, B.; Nagy, V.

    The role of soil structure on saturated hydraulic conductivity changes is studied in plough layers of texturally different soils. Three localities in western part of Slovakia in Zitny ostrov (Corn Island) were under investigation: locality Kalinkovo with light Calcaric Fluvisol (FAO 1970), Macov with medium heavy Calcari-mollic Fluvisol and Jurova with heavy Calcari-mollic Fluvisol. Soil structure was determined in dry as well as wet state and in size of macro and micro aggregates. Saturated hydraulic conductivity was measured by the help of double ring method. During the period of ring filling the soil surface was protected against aggregates damage by falling water drops. Spatial and temporal variability of studied parameters was evaluated. Cultivated crops were ensilage maize at medium heavy and heavy soil and colza at light soil. Textural composition of soil and actual water content at the beginning of measurement are one of major factor affecting aggregate stability and consequently also saturated hydraulic conductivity.

  19. CALCAR PRESERVING OSTEOTOMY IN CEMENTED BIPOLAR HEMIARTHROPLASTY FOR UNSTABLE TROCHANTERIC FRACTURES

    Directory of Open Access Journals (Sweden)

    Mohammed Ashraf

    2016-03-01

    Full Text Available INTRODUCTION Intertrochanteric fractures in osteoporotic bones which are grossly comminuted are highly unstable and difficult to treat. Conservative treatment with traction and prolonged immobilisation lands up with many complications and often fatality. Rate of failure with internal fixation has been found to be high, especially in osteoporotic bones. Revision osteosynthesis is technically demanding and it leads to complications, a second surgical procedure for revision synthesis, arthroplasty or removal of a symptomatic implant is again a risky procedure in elderly patients with lot of comorbidities. The aim of this study was to assess the efficacy of a cemented bipolar hemiarthroplasty with calcar preserving intracapsular osteotomy in the management of unstable trochanteric fractures in elderly patients with osteoporosis. Hemiarthroplasty in unstable trochanteric fractures have been described in the past with varying outcome. The reasons for poor outcome were shortening, varus positioning and abductor insufficiency. This was mainly due to the deficient medial support due to the removal of lesser trochanter and calcar. Recently, free calcar grafting excised from the removed neck for medial support was reported, but in our technique we are preserving the calcar and lesser trochanter with all its soft tissue and muscle attachments. MATERIALS AND METHODS 52 patients with mean age 71.4 (range from 65 to 89 who underwent cemented bipolar hemiarthroplasty with calcar preserving osteotomy for unstable intertrochanteric fractures were prospectively evaluated. Posterior approach was used in all patients. Harris hip score was used for the clinical evaluation. The mean followup period was 5 years. RESULT In our study, which was done on 52 cases which had a mean age 71.4 years. The average Harris hip score was 81. Excellent to fair results were obtained at followup in 50 (96% cases, and in 2(4% cases the results were poor. Average hospital stay was 14

  20. Stable isotope and calcareous nannofossil assemblage record of the late Paleocene and early Eocene (Cicogna section)

    Science.gov (United States)

    Agnini, Claudia; Spofforth, David J. A.; Dickens, Gerald R.; Rio, Domenico; Pälike, Heiko; Backman, Jan; Muttoni, Giovanni; Dallanave, Edoardo

    2016-04-01

    We present records of stable carbon and oxygen isotopes, CaCO3 content, and changes in calcareous nannofossil assemblages across an 81 m thick section of upper Paleocene-lower Eocene marine sedimentary rocks now exposed along the Cicogna Stream in northeast Italy. The studied stratigraphic section represents sediment accumulation in a bathyal hemipelagic setting from approximately 57.5 to 52.2 Ma, a multi-million-year time interval characterized by perturbations in the global carbon cycle and changes in calcareous nannofossil assemblages. The bulk carbonate δ13C profile for the Cicogna section, once placed on a common timescale, resembles that at several other locations across the world, and includes both a long-term drop in δ13C and multiple short-term carbon isotope excursions (CIEs). This precise correlation of widely separated δ13C records in marine sequences results from temporal changes in the carbon composition of the exogenic carbon cycle. However, diagenesis has likely modified the δ13C record at Cicogna, an interpretation supported by variations in bulk carbonate δ18O, which do not conform to expectations for a primary signal. The record of CaCO3 content reflects a combination of carbonate dilution and dissolution, as also inferred at other sites. Our detailed documentation and statistical analysis of calcareous nannofossil assemblages show major differences before, during and after the Paleocene-Eocene Thermal Maximum. Other CIEs in our lower Paleogene section do not exhibit such a distinctive change; instead, these events are sometimes characterized by variations restricted to a limited number of taxa and transient shifts in the relative abundance of primary assemblage components. Both long-lasting and short-lived modifications to calcareous nannofossil assemblages preferentially affected nannoliths or holococcoliths such as Discoaster, Fasciculithus, Rhomboaster/Tribrachiatus, Sphenolithus and Zygrhablithus, which underwent distinct variations in

  1. Experimental study on engineering properties of coral reef calcareous rock%珊瑚礁礁灰岩工程特性测试研究

    Institute of Scientific and Technical Information of China (English)

    刘志伟; 李灿; 胡昕

    2012-01-01

    珊瑚礁是一种特殊的岩土类型。运用现场钻探、标准贯入试验、波速测试、平板载荷试验等勘探手段和方法,对沙特红海珊瑚礁礁灰岩进行了含水率、重度、抗压强度等室内试验,分析研究了珊瑚礁礁灰岩的物理力学性质及相关关系。测试研究表明:岩芯采取率、岩石质量指标和标准贯入试验可以评价珊瑚礁礁灰岩沿深度的岩土性能变化特征;珊瑚礁礁灰岩具有结构多变、多孔、重度小、性脆、强度低且变化大等工程特性;珊瑚礁弹性波传播速度小,而珊瑚碎屑岩和珊瑚状石灰岩具有较高的弹性波波速;载荷试验p-s曲线与其他岩土不同,随着荷载的增大,礁灰岩空隙发生了脆性破坏,岩土被压密。测试成果可供礁灰岩的进一步研究和工程应用参考。%Coral reef is a special type of rock and soil. Based on drilling, standard penetration test, elastic velocity test and plate loading test, laboratory rock tests such as moisture content, unit dry weight and uniaxial compressive strength etc. are carried out, and the physical and mechanical properties and mutual relations are analyzed and researched. It shows that the core recovery, rock quality designation and standard penetration test may evaluate the rock and soil properties change along the depth. The coral reef rocks have the engineering properties of changeable structure, porous, low density, brittleness and low strength and great change. Coral reefs have the low elastic velocity, but calcareous rocks have the high elastic velocity relatively. The pressure and settlement curves of plate loading test are differ from other rocks and soils. As the load increases, calcareous rock voids occur brittle failure, and rocks and soils are compacted. Research results are significant in coral reef area and engineering application.

  2. A multidisciplinary methodology for the characterization of a large rock spread in the Northern Calcareous Alps (Eastern Alps)

    Science.gov (United States)

    Melzner, Sandra; Ottowitz, David; Pfeiler, Stefan; Moser, Michael; Motschka, Klaus; Lotter, Michael; Mandl, Gerhard Walter; Rohn, Joachim; Otter, Juergen; Wimmer-Frey, Ingeborg

    2015-04-01

    The Northern Calcareous Alps are characterized by complex lithological and tectonic settings, which are a consequence of the multiphase Alpine orogeny. Several tectonic events caused a varying structural anisotropy with a high susceptibility towards certain types of gravitational mass movement. Mt. Plassen is situated west of the Hallstatt village (Upper Austria). It is composed of Jurassic limestone, which overlies Permotriassic fine-grained clastic rocks and evaporites (mainly part of the so-called Haselgebirge). This geotechnical predisposition causes rock spreading of the more hard and rigid limestone on the weak, mainly clayey rocks. Associated to this large slope instability are secondary rockfall and sliding processes. Further common process chains include rockfall triggering slides and/or earth flows by undrained loading of the ductile clay material. Thus, such fast moving flows/slides may endanger the houses and infrastructures in the Salzberg high valley and Hallstatt village. Recent rockfall activity at Mt. Plassen provide evidences for greater, perhaps accelerating displacement rates of the rock spread. A multidisciplinary assessment strategy was chosen to analyse the ground conditions, to characterize the potential failure mechanisms in more detail and to evaluate the hazard potential of future events. Methods include field mapping (geologic, engineering geologic and geomorphologic), sampling and determination of soil parameters in active process areas, geophysical surveys (airborne geophysics and geoelectric measurements) and kinematic measurements (tape dilatometer and geodetic measurements over a period of 50 years). Results of this multidisciplinary approach form the basis for further decision making such as the installation of a monitoring system or other preventive measures.

  3. Temperature Effect on Boron Adsorption—Desorption Kinetics in Soils

    Institute of Scientific and Technical Information of China (English)

    ZHUDUANWEI; SHILEI; 等

    1999-01-01

    The effect of temperature on the properties of boron adsorption-desorption in brown-red soil,yellowbrown soil and calcareous alluvial soil of Hubei Province was investigated with the mobile displacement technique.The experimental data of B adsorption-desorption amounts and reaction time at 25 and 40℃ were fitted by the zero-order,first-order and parabolic diffusion kinetic equations.The adsorption process was in conformity with the parabolic diffusion law at both the temperatures,and the values of rate constant of the parabolic diffusion equation in B adsorption were 0.138,0.124 and 0.105 mg kg-1 min-1/2 at 25℃,and 0.147,0.146and 0.135mg kg-1 min1/2 at 40℃ for the brown-red soil,yellow-brown soil,and calcareous alluvial soil,respectively,The relationship between amount of B desorption and reaction time could be well described by the first-order kinetic equation,and the corresponding values of rate constant were 0.0422,0.0563 and 0.0384min-1 at 25℃,and 0.0408,0.0423 and 0.0401min-1 at 40℃ for the brown-red soil,the yellow-brown soil and the calcareous alluvial soil,respectively.Therefore,the desorption process of B might be related to the amount of B adsorbed in soil,The higher th temperature,the lower the amount of B adsorption of the same soil in the same reaction time,The values of the apparent activation energy of B adsorption in the three soils calculated with the rate constants of parabolic diffusion equation were 3.27,8.44 and 12.99 kJ mol-1,respectively,based on the experimental data of B adsorption amounts and reaction time at and 40℃.

  4. The effects of soil amendments on heavy metal bioavailability in two contaminated Mediterranean soils

    Energy Technology Data Exchange (ETDEWEB)

    Walker, D.J.; Clemente, Rafael; Roig, Asuncion; Bernal, M.P

    2003-04-01

    The effects of organic amendments on metal bioavailability were not always related to their degree of humification. - Two heavy metal contaminated calcareous soils from the Mediterranean region of Spain were studied. One soil, from the province of Murcia, was characterised by very high total levels of Pb (1572 mg kg{sup -1}) and Zn (2602 mg kg{sup -1}), whilst the second, from Valencia, had elevated concentrations of Cu (72 mg kg{sup -1}) and Pb (190 mg kg{sup -1}). The effects of two contrasting organic amendments (fresh manure and mature compost) and the chelate ethylenediaminetetraacetic acid (EDTA) on soil fractionation of Cu, Fe, Mn, Pb and Zn, their uptake by plants and plant growth were determined. For Murcia soil, Brassica juncea (L.) Czern. was grown first, followed by radish (Raphanus sativus L.). For Valencia soil, Beta maritima L. was followed by radish. Bioavailability of metals was expressed in terms of concentrations extractable with 0.1 M CaCl{sub 2} or diethylenetriaminepentaacetic acid (DTPA). In the Murcia soil, heavy metal bioavailability was decreased more greatly by manure than by the highly-humified compost. EDTA (2 mmol kg{sup -1} soil) had only a limited effect on metal uptake by plants. The metal-solubilising effect of EDTA was shorter-lived in the less contaminated, more highly calcareous Valencia soil. When correlation coefficients were calculated for plant tissue and bioavailable metals, the clearest relationships were for Beta maritima and radish.

  5. Natural Nitrogen—15 Abundance of Ammonium Nitrogen and Fixed Ammonium in Soils

    Institute of Scientific and Technical Information of China (English)

    SHISHU-LIAN; XINGGUANG-XI; 等

    1992-01-01

    The present article deals with the natural nitrogen-15 abundance of ammonium nitrogen and fixed ammonium in different soils.Variations in the natural 15N abundance of ammonium nitrogen mineralized in soils under anaerobic incubation condition were related to soil pH.The δ 15N of mineralizable N in acid soils was lower but that in neutral and calcareous soils was higher compared with the δ 15N of total N in the soils.A variation tendence was also found in the δ 15N of amino-acid N in the hydrolysates of soils.The natural 15N abundance of fixed ammonium was higher than that of total N in most surface soils and other soil horizons,indicating that the increase of δ 15N in the soil borizons beneath subsurface horizon of some forest soils and acid paddy soils was related to the higher δ 15N value of fixed ammonium in the soil.

  6. Delimitation of the Thoracosphaeraceae (Dinophyceae), including the calcareous dinoflagellates, based on large amounts of ribosomal RNA sequence data.

    Science.gov (United States)

    Gottschling, Marc; Soehner, Sylvia; Zinssmeister, Carmen; John, Uwe; Plötner, Jörg; Schweikert, Michael; Aligizaki, Katerina; Elbrächter, Malte

    2012-01-01

    The phylogenetic relationships of the Dinophyceae (Alveolata) are not sufficiently resolved at present. The Thoracosphaeraceae (Peridiniales) are the only group of the Alveolata that include members with calcareous coccoid stages; this trait is considered apomorphic. Although the coccoid stage apparently is not calcareous, Bysmatrum has been assigned to the Thoracosphaeraceae based on thecal morphology. We tested the monophyly of the Thoracosphaeraceae using large sets of ribosomal RNA sequence data of the Alveolata including the Dinophyceae. Phylogenetic analyses were performed using Maximum Likelihood and Bayesian approaches. The Thoracosphaeraceae were monophyletic, but included also a number of non-calcareous dinophytes (such as Pentapharsodinium and Pfiesteria) and even parasites (such as Duboscquodinium and Tintinnophagus). Bysmatrum had an isolated and uncertain phylogenetic position outside the Thoracosphaeraceae. The phylogenetic relationships among calcareous dinophytes appear complex, and the assumption of the single origin of the potential to produce calcareous structures is challenged. The application of concatenated ribosomal RNA sequence data may prove promising for phylogenetic reconstructions of the Dinophyceae in future.

  7. 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.

  8. 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...... purposes. It might, in species like Ammonia batavus, have become a kind of antipredatory device or mimicry. A predator might conceive such a species as an agglutinating species and neglect it. The secondary test is a delicate structure in most species and is easily destroyed by the rough sampling...

  9. 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.

  10. APTIAN TO CAMPANIAN CALCAREOUS NANNOFOSSILS BIOSTRATIGRAPHY FROM THE BOTTACCIONE SECTION, GUBBIO, CENTRAL ITALY

    Directory of Open Access Journals (Sweden)

    FABRIZIO TREMOLADA

    2002-11-01

    Full Text Available Late Aptian-Campanian biostratigraphic investigations performed on calcareous nannofossils provided a refined stratigraphic resolution  of the Scisti a Fucoidi and Scaglia Formations in the Bottaccione section (Umbria-Marche Basin, Central italy. Additional bioevents such as the Last Occurrence (LO of both Assipetra infracretacea larsonii and Rucinolithus terebrodentarius youngii and the First Occurrences (FOs of Pararhabdolithus achlyostaurion and large Biscutum constans were detected and might be used to refine the Late Aptian-Albian biostratigraphy at low latitudes.   

  11. Effect of Oxalic Acid on Potassium Release from Typical Chinese Soils and Minerals

    Institute of Scientific and Technical Information of China (English)

    TU Shu-Xin; GUO Zhi-Fen; SUN Jin-He

    2007-01-01

    Oxalic acid plays an important role in improving the bioavailability of soil nutrients. Batch experiments were employed to examine the influences of oxalic acid on extraction and release kinetics of potassium (K) from soils and minerals along with the adsorption and desorption of soil K+. The soils and minerals used were three typical Chinese soils, black soil (Mollisol), red soil (Ultisol), and calcareous alluvial soil (Entisol), and four K-bearing minerals, biotite, phlogopite, muscovite, and microcline. The results showed that soil K extracted using 0.2 mol L-1 oxalic acid was similar to that using 1 mol L-1 boiling HNO3. The relation between K release (y) and concentrations of oxalic acid (c) could be best described logarithmically as y=a+blogc, while the best-fit kinetic equation of K release was y=a +b√t, where a and b are the constants and t is the elapsed time. The K release for minerals was ranked as biotite> phlogopite>> muscovite> microcline and for soils it was in the order: black soil> calcareous alluvial soil> red soil. An oxalic acid solution with low pH was able to release more K from weathered minerals and alkaline soils. Oxalic acid decreased the soil K+ adsorption and increased the soil K+ desorption, the effect of which tended to be greater at lower solution pH, especially in the red soil.

  12. Technical Note: Disturbance of soil structure can lead to release of methane entrapped in glacier forefield soils

    Directory of Open Access Journals (Sweden)

    P. A. Nauer

    2013-09-01

    Full Text Available Investigations of sources and sinks of atmospheric CH4 are needed to understand the global CH4 cycle and climate-change mitigation options. Glaciated environments might play a critical role due to potential feedbacks with global glacial meltdown. In an emerging glacier forefield, an ecological shift occurs from an anoxic, potentially methanogenic subglacial sediment to an oxic proglacial soil, in which soil-microbial consumption of atmospheric CH4 is initiated. The development of this change in CH4 turnover can be quantified by soil-gas profile analysis. We found evidence for CH4 entrapped in glacier forefield soils when comparing two methods for the collection of soil-gas samples: a modified steel rod (SR designed for one-time sampling and rapid screening (samples collected ~ 1 min after hammering the SR into the soil, and a novel multi-level sampler (MLS for repetitive sampling through a previously installed access tube (samples collected weeks after access-tube installation. In glacier forefields on siliceous bedrock, sub-atmospheric CH4 concentrations were observed with both methods. Conversely, elevated soil-CH4 concentrations were observed in calcareous glacier forefields, but only in samples collected with the SR, while MLS samples all showed sub-atmospheric CH4 concentrations. Time-series SR soil-gas sampling (additional samples collected 2, 3, 5, and 7 min after hammering confirmed the transient nature of the elevated soil-CH4 concentrations, which were decreasing from ~ 100 μL L−1 towards background levels within minutes. This hints towards the existence of entrapped CH4 in calcareous glacier forefield soil that can be released when sampling soil-gas with the SR. Laboratory experiments with miniature soil cores collected from two glacier forefields confirmed CH4 entrapment in these soils. Treatment by sonication and acidification resulted in a massive release of CH4 from calcareous cores (on average 0.3–1.8 μg CH4 (g d.w.−1

  13. Application of Taguchi method for the characterization of calcareous deposits formed by pulse cathodic protection

    Energy Technology Data Exchange (ETDEWEB)

    Zamanzade, M.; Shahrabi, T. [Department of Materials Science and Engineering, Faculty of Engineering, Tarbiat Modares University, Tehran (Iran); Gharacheh, E.A. [Department of Industrial Engineering, Faculty of Engineering, Tarbiat Modares University, Tehran (Iran)

    2007-09-15

    In this study, the Taguchi method, a powerful tool to design optimization for quality, is used to find the optimal process parameters of pulse cathodic protection system for the calcareous deposits' formation. An orthogonal array, main effect and the signal-to-noise (S/N) ratio are employed to investigate the process parameters in order to achieve optimum final current density. Through this study also the main process parameters that affect the calcareous deposits' formation can be found. Experiments were carried out to confirm the effectiveness of this approach. From the results, chronoamperometric measurements have been used to evaluate the influence of pulse cathodic protection on decreasing the required cathodic current for protection and also decreasing the surface coverage. The morphology of the formed deposits has been evaluated through scanning electron microscopy (SEM) and chemical analysis of the formed deposits has been performed using X-ray diffraction (XRD). It is found that the different environmental conditions, i.e., Ca{sup 2+} concentration, Mg{sup 2+} concentration, rotation speed, and temperature significantly affect the final required current density of the pulse cathodic protection. The optimum levels of parameters at different frequencies are also presented. (Abstract Copyright [2007], Wiley Periodicals, Inc.)

  14. Microbial isotopic signatures in calcareous tufa from Punta Mita coastal vents, Mexico

    Science.gov (United States)

    Canet, C.; Prol-Ledesma, R. M.; Melgarejo, J. C.; Reyes, A.

    2002-12-01

    Numerous small calcareous mounds accompanied by Ba, Hg and Tl mineralization occur in shallow submarine hydrothermal manifestations on the sea bottom, at 10 m depth, in Punta Mita (Western coast of Mexico). The formation of calcite mounds in these coastal vents provides an uncommon example of calcareous tufa deposits in a submarine hydrothermal environment. The hydrothermal activity consists in water and gas (essentially nitrogen and methane) venting at 85°C, through a 100 m fissure hosted in basaltic rocks and partially covered by unconsolidated sediments. The mounds consist of travertine-like metre-sized calcite aggregates that develop around the main submarine hot springs. Barite, sulphides (mostly pyrite and cinnabar) and phosphates (carbonate-hydroxylapatite) are also present in these mounds. Two main calcite types are texturally distinguished: firstly an earlier radial-fibrous generation, and a later fine-grained calcite generation that cements the detrital grains and fills the pore spaces. Stable isotope analyses were performed in calcite from these mounds. The δ13C measured values show a strong depletion in 13C, with values as low as -39.2 per mil (PDB). These values agree with a microbially mediated calcite mineralization process, by means of bacterial oxidation of vent derived methane. In contrast to most known cases of microbial methane oxidation, in Punta Mita this process took place under hydrothermal conditions.

  15. 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.

  16. MAASTRICHTIAN TO EOCENE CALCAREOUS NANNOFOSSIL BIOSTRATIGRAPHY FROM THE TABIAGO SECTION, BRIANZA AREA, NORTHERN ITALY

    Directory of Open Access Journals (Sweden)

    FABRIZIO TREMOLADA

    2008-03-01

    Full Text Available Calcareous nannofossil biostratigraphic investigations have been carried out on samples collected from the Tabiago section, Brianza, northern Italy. This section records early Maastrichtian (CC23b nannofossil zone to early Eocene (NP10 nannofossil zone calcareous nannofossil assemblages. The Cretaceous-Tertiary transition is characterized by major changes in sedimentation rates and two likely stratigraphic gaps. The Cretaceous Brenno Formation was deposited with a high sedimentation rate (~20 m/m.y., whilst the Tabiago Formation of Paleogene age records a drastic decrease (~10 m/m.y.. The absence of the CC26 zonal marker Micula prinsii may indicate a stratigraphic hiatus or an extremely condensed level in the latest Maastrichtian. However, only two samples have been collected and analyzed in this interval due to low exposure of the outcrop, and the absence of M. prinsii could be the result of diagenetic overprint or insufficient sampling. A stratigraphic hiatus or a very condensed interval corresponds to the upper part of NP1 nannofossil zone and PƒÑ foraminiferal Zone and P1a Subzone in the early Paleocene. The poor exposure of the outcrop prevents to precisely locate the zonal boundaries between NP4 and NP5 and between NP9 and NP10 and impedes the documentation of possible further stratigraphic gaps or condensed intervals.    

  17. A regional reconstruction of debris-flow activity in the Northern Calcareous Alps, Austria

    Science.gov (United States)

    Procter, Emily; Bollschweiler, Michelle; Stoffel, Markus; Neumann, Mathias

    2011-09-01

    Dendrogeomorphic dating of historical debris-flow events is a highly valuable tool for improving historical records in the field of natural hazard management. Previous dendrogeomorphic investigations generally have focused on case studies of single torrents; however, regional investigations may offer a more accurate reconstruction of regional patterns of activity and therefore may have an advantage over individual cases. The aim of the study is to provide a regional reconstruction of debris-flow events for a site in the Northern Calcareous Alps of western Austria (Gamperdonatal, Vorarlberg) and to document spatial and temporal morphological changes in individual and neighboring torrents. Analysis of 442 trees (268 Pinus mugo ssp. uncinata, 164 Picea abies, and 10 Abies alba) allowed identification of 579 growth disturbances corresponding to 63 debris-flow events since A.D. 1839. The majority of growth disturbances were in the form of growth suppression or release (76%) owing to the nature of both the deposited material and the process characteristics. Regional patterns of event frequency indicated a paucity of activity in the early to mid-twentieth century and increased activity since A.D. 1948, whereby large events were followed by subsequent years of continued activity of smaller magnitude. Patterns of frequency could be attributed primarily to spatiotemporal changes in channel morphology, but may also be reflective of changes in transport conditions within the valley. This study provides the first regional investigation in the Austrian Alps and contributes to the documentation of tree responses to geomorphic disturbances in calcareous material.

  18. Trochanter/calcar preserving reconstruction in tumors involving the femoral head and neck

    Science.gov (United States)

    Cho, Hwan Seong; Lee, Young-Kyun; Ha, Yong-Chan; Koo, Kyung-Hoi

    2016-01-01

    AIM: To evaluate the results of hip reconstruction with extensive excision for tumor confined to the femoral head and neck. METHODS: We designed a resection preserving the greater trochanter and lower portion of calcar femorale, and utilized conventional total hip prosthesis. We retrospectively reviewed 7 patients, who underwent a wide resection and reconstruction using conventional hip prosthesis. There were 3 men and 4 women and their mean age was 42.5 years (22 to 65 years). The histologic diagnosis of each patient was low-grade osteosarcoma, diffuse large B-cell lymphoma, liposclerosing myxofibroma, intraosseous lipoma, chondroblastoma, giant cell tumor and focal intramedullary fibrosis. RESULTS: One patient with lymphoma died due to disease dissemination at 10 mo postoperatively and the remaining 6 patients were followed for a mean of 4.7 years (3 to 6 years). All patients were able to return to their daily activities and no patient had local recurrence. No radiographic signs of loosening, wear, and osteolysis were found at the last follow-up. CONCLUSION: Trochanter/calcar-preserving resection of the proximal femur and reconstruction using conventional total hip prosthesis, is a satisfactory treatment for tumors confined to the femoral head and neck. PMID:27458555

  19. Incorporation of calcium into the soft tissues and calcareous corpuscles of larval Taenia taeniaeformis.

    Science.gov (United States)

    von Brand, T; Weinbach, E C

    1975-12-11

    Larval Taenia taeniaeformis in vivo accumulates 45Ca2+ in soft tissues and calcareous corpuscles. Radioactivity was demonstrable in the corpuscles six months after a single dose of 45Ca2+ was administered to the host by means of a stomach tube. Ca2+ also was taken up by isolated larvae. Accumulation in vitro was more rapid then in vivo and was correlated with the external Ca2+ concentration. Temperature variation, oxygen availability, and metabolic inhibitors had little effect on the Ca2+ uptake, indicating that active transport of Ca2+ is unlikely in this parasite. Variations in the external Pi concentrations had no effect on Ca2+ accumulation or on its distribution. Addition of 5% CO2 increased the uptake of Ca2+ by the calcareous corpuscles under anaerobic conditions. Radioactivity from NaH14CO3 also was accumulated in soft tissues and corpuscles of T. taeniaeformis. Assuming that the 14C taken up by the corpuscles was in the form of 14CO3(2-), the ratio of Ca2+ to CO3(2-) accumulation in the corpuscles approximates the ratio of these constituents in dolomite: CaMg(CO3)2.

  20. 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.

  1. Dark gray soils on two-layered deposits in the north of Tambov Plain: Agroecology, properties, and diagnostics

    Science.gov (United States)

    Zaidelman, F. R.; Nikiforova, A. S.; Stepantsova, L. V.; Volokhina, V. P.

    2012-05-01

    Dark gray soils in the Tambov Plain are developed from the light-textured glaciofluvial deposits underlain by the calcareous loam. Their morphology, water regime, and productivity are determined by the depth of the slightly permeable calcareous loamy layer, relief, and the degree of gleyzation. The light texture of the upper layer is responsible for its weak structure, high density, the low content of productive moisture, and the low water-holding capacity. If the calcareous loam is at a depth of 100-130 cm, dark gray soils are formed; if it lies at a depth of 40-70 cm, temporary perched water appears in the profile, and dark gray contact-gleyed soils are formed. Their characteristic pedofeatures are skeletans in the upper layers, calcareous nodules in the loamy clay layer, and iron nodules in the podzolized humus and podzolic horizons. The appearance of Fe-Mn concretions is related to gleyzation. The high yield of winter cereals is shown to be produced on the dark gray soils; the yields of spring crops are less stable. Spring cereals should not be grown on the contact-gleyed dark gray soils.

  2. Calcareous sinter from ancient aqueducts as a source of data in paleoclimate, tectonics and hydrology

    Science.gov (United States)

    Surmelihindi, G.; Passchier, C. W.

    2010-12-01

    During the lifetime the Roman Empire (300BC-400AD), about 1200 major aqueducts were built to supply cities in the Mediterranean with drinking water. The ruins of many of these channels contain sinter (calcium carbonate), which was deposited at a rate of 0.5-5 mm/year over the life of the aqueduct, usually 50-200 but up to 1000 years. Calcareous sinter inside the ancient aqueduct channels can give important insight into paleoclimatology in the form of temperature and rainfall, reflect palaeohydrology of water, water chemistry, flow rate, bacterial activity and source area of the water. This type of data is important to build climate models and to understand earthquake and flood patterns in the Mediterranean, and can be a new, additional source of information besides speleothems, travertine and tufa deposits. In our study we focus on Mediterranean climate patterns, and selected four aqueduct sites from Southern Turkey, Greece and Italy. The calcareous sinter deposits may reflect annual or subannual lamination characterized by alternating light, dense, coarse-grained and dark, porous, microcrystalline layers which are thought to represent winter and summer conditions respectively. Moreover, abrupt changes in the sequence of lamination can be a signal of natural hazards such as earthquakes or flood events. Deposits from the aqueduct of Patara (Southern Turkey) show 40-50 laminae couples, which may be annual layers. δ18O and δ 13C stable isotope data indicate high cyclicity within the sinter samples from Patara during the Roman period. Higher δ18O values correspond with dark, porous layers and lower values with light, dense layers. Major geochemical analyses show similar seasonal changes. Electron microprobe study shows that within dark laminae, detrital Fe, Mg, K, Al and Si are enriched whereas the light layers have high Ca content. Trace element analyses by LA-ICP-MS also indicate higher Mg/Ca and Sr/Ca values in the dark layers, which can be interpreted in terms

  3. 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

  4. Some features of soil organic matter in parks and adjacent residential areas of Moscow

    Science.gov (United States)

    Prokof'eva, T. V.; Rozanova, M. S.; Poputnikov, V. O.

    2013-03-01

    The humus-accumulative horizons of soils from two natural-historical parks of Moscow and the adjacent residential areas were studied. An increase in the concentration of organic matter was observed in the soils of the residential areas. A tendency toward the formation of fulvate humus typical for southern taiga soils persisted in the low-carbonate nongleyed humus-accumulative horizons. At the same time, the transformation rate, character, and content of organic matter in the urban soils were strongly affected by the contamination, calcareous invasion, and remediation of the soils and sediments.

  5. Future prospects for the rare, late-flowering Gentianella germanica and Gentianopsis ciliata in Dutch nutrient-poor calcareous grasslands.

    NARCIS (Netherlands)

    Oostermeijer, J.G.B.; Luijten, S.H.; Ellis-Adam, A.C.; den Nijs, J.C.M.

    2002-01-01

    We discuss the population biology of two calcareous grassland gentians, Gentianella germanica and Gentianopsis ciliata, in relation to the habitat management currently practiced in The Netherlands. There, at the margin of their range, both species are rare. Gentianella germanica persists on six rema

  6. 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.

  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. 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.

  9. Characteristics of Phosphorous Adsorption and Desorption by Organo-Mineral Colloidal Complexes of Purple Paddy Soils

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The kinetic characteristics of P adsorption and desorption by organo-mineral colloidal complexes (OMC)were studied using acid, calcareous and neutral purple paddy soils taken from Chongqing and Sichuan, China.The results showed that the P adsorption capacity of the organo-mineral colloidal complexes differed with the soil types, being higher for the acid and calcareous purple soils than for the neutral purple soils. Partial removal of the organic matter increased the adsorption capacity of the colloidal complexes. A very significant positive correlation was found between the amounts of P desorbed from OMC and the P saturation degrees.The P adsorption reaction was quick at the early stage and slowed later. The raise of temperature increased P adsorption capacity and P adsorption rate of the colloidal complexes. The adsorption processes could be described by the Elovich equation.

  10. Calcareous nannofossil assemblages from the Central Mediterranean Sea over the last four centuries: the impact of the little ice age

    Directory of Open Access Journals (Sweden)

    A. Incarbona

    2010-05-01

    Full Text Available We present decadal-scale calcareous nannofossil data from four short cores (Station 272, 37° 17' N, 12° 48' E, 226 m depth; St 342, 36° 42' N, 13° 55' E, 858.2 m depth; St 407, 36° 23' N, 14° 27' E, 345.4 m depth; C90-1M, 40° 36' N, 14° 42' E, 103.4 m depth recovered in the central Mediterranean Sea (northern Sicily Channel and Tyrrhenian Sea, which, on the basis of 210Pb activity span the last 200–350 years. Assemblages are dominated by placoliths, mostly Emiliania huxleyi, while, at least in the Sicily Channel sediments, Florisphaera profunda was an important part of the coccolithophore community.

    The paleoenvironmental reconstruction, based on ecological preference of species and groups, suggests that the Tyrrhenian core C90-1M maintained higher productivity levels over recent centuries, with respect to the Sicily Channel sites, possibly because of more pronounced winter phytoplankton blooms, in agreement with modern primary productivity variations over the last ten years.

    The lowermost part of the record of one of the cores from the Sicily Channel, Station 407, which extends down to 1650 AD, is characterized by drastic changes in productivity. Specifically, below 1850 AD, the decrease in abundance of F. profunda and the increase of placoliths, suggest increased productivity. The chronology of this change is related to the main phase of the Little Ice Age, which might have impacted the hydrography of the southern coast of Sicily and promoted vertical mixing in the water column. The comparison with climatic forcings points out the importance of stronger and prolonged northerlies, together with decreased solar irradiance. The identification of the LIA in the northern Sicily Channel cover the Bond cycle BO that was missing in a previous study of Holocene climatic anomalies in the Sicily Channel.

    Finally, we suggest that major abundance changes in reworked nannofossil specimens

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

    Science.gov (United States)

    Hayes, Felicity; Williamson, Jennifer; Mills, Gina

    2012-04-01

    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 30ppb to 70ppb 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.

  12. Calcareous nannofossil evidence for the existence of the Gulf Stream during the late Maastrichtian

    Science.gov (United States)

    Watkins, D.K.; ,

    2005-01-01

    Upper Maastrichtian calcareous nannofossil assemblages, from eight cores on the South Carolina Coastal Plain (onshore set) and three deep sea drilling sites from the continental slope and abyssal hills (offshore set), were analyzed by correlation and principal component analysis to examine the ancient surface water thermal structure. In addition, a temperature index derived from independently published paleobiogeographic information was applied to the sample data. All three methods indicate a strong separation of the samples into onshore and offshore sets, with the offshore data set exhibiting significantly warmer paleotemperatures. The great disparity between these two sample sets indicates that there was a strong thermal contrast between the onshore and offshore surface water masses that persisted throughout the late Maastrichtian despite evident shortterm changes in fertility, productivity, and community structure. This suggests the Gulf Stream was present as a major oceanographic feature during the late Maastrichtian. Copyright 2005 by the American Geophysical Union.

  13. 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.

  14. Colour change evaluation on UV radiation exposure for Păun-Repedea calcareous geomaterial

    Science.gov (United States)

    Pelin, V.; Sandu, I.; Munteanu, M.; Iurcovschi, C. T.; Gurlui, S.; Sandu, AV; Vasilache, V.; Brȃnzilă, M.; Sandu, I. G.

    2016-06-01

    When talking about the preservation treatments that can be applied to natural stones used in different constructions, the surface hydrophobization plays an important part, especially when referring to porous surfaces like the calcareous oolithic stones specific to Repedea area, Iasi County, Romania. The present paper presents a method that evaluates the hydrophobization efficiency of two types of pellicles, involving UV artificial ageing and colorimetric analysis of the treated surfaces. The evaluation was done through continuous colorimetric monitoring and by comparing the evolution of the chromatic modifications of the two treated surfaces with the original colorimetric values and with the witness area, which was exposed to UV radiations under the same conditions, but left chemical untreated. The techniques used during this experiment were: CIE L*a*b* colorimetry, OM, SEM-EDX, UV radiation exposure and Spectrum Irradiance Measurement.

  15. Mechanical robustness of the calcareous tubeworm Hydroides elegans: warming mitigates the adverse effects of ocean acidification.

    Science.gov (United States)

    Li, Chaoyi; Meng, Yuan; He, Chong; Chan, Vera B S; Yao, Haimin; Thiyagarajan, V

    2016-01-01

    Development of antifouling strategies requires knowledge of how fouling organisms would respond to climate change associated environmental stressors. Here, a calcareous tube built by the tubeworm, Hydroides elegans, was used as an example to evaluate the individual and interactive effects of ocean acidification (OA), warming and reduced salinity on the mechanical properties of a tube. Tubeworms produce a mechanically weaker tube with less resistance to simulated predator attack under OA (pH 7.8). Warming (29°C) increased tube volume, tube mineral density and the tube's resistance to a simulated predatory attack. A weakening effect by OA did not make the removal of tubeworms easier except for the earliest stage, in which warming had the least effect. Reduced salinity (27 psu) did not affect tubes. This study showed that both mechanical analysis and computational modeling can be integrated with biofouling research to provide insights into how fouling communities might develop in future ocean conditions.

  16. 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. 

  17. 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.

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

    Science.gov (United States)

    Roik, Anna; Roder, Cornelia; Röthig, Till; Voolstra, Christian R.

    2016-06-01

    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.

  19. Integrated biostratigraphy and sealevel dynamics at the Santonian - early Campanian Schattau section - Northern Calcareous Alps, Austria

    Science.gov (United States)

    Wolfgring, Erik; Wagreich, Michael

    2016-04-01

    The Schattau section displays a Santonian to early Campanian transgressive sequence with a rich micro- and macro fossil fauna. A framework based on planktonic foraminifera, calcareous nannoplankton, ammonite, echinoid and crinoid biostratigraphy provides the foundation for a high resolution assessment of palaeoecologic changes in planktonic and benthic foraminiferal communities and local biostratigraphy (see Wagreich et al., 2009). The Santonian Hochmoos Formation (representing shallow water environments with the Sandkalkbank Member at the top of this unit) is overlain by the Santonian to Campanian Bibereck Formation (recording a distinct increase in water depth). The stratigraphically older subsections of the outcrop yield abundant miliolids and some rotaliid foraminiferal taxa (Quinqueloculina sp., Spiroloculina fassistomata, Hoeglundia spp., Gavellina spp.) and the larger benthic foraminifer Nummofallotia cretacea. A transgressive episode is recorded in the uppermost Hochmoos Formation's Sandkalkbank Member - consequently larger benthic foraminifera disappear and miliolids become a rare -, planktonic foraminifera an abundant element in deposits assigning to the stratigraphically youngest part of the Schattau section, the Bibereck Formation. Globotruncanids and marginotruncanids are frequently found. The planktonic/benthic foraminifera ratio rises from zero to ~50%. The benthic foraminiferal fauna is characterised by tubular and bi- and triserial agglutinated foraminifera (e.g. Ammobaculites spp., Dorothia spp., Gaudryina spp., Tritaxia spp.) as well as spiral calcareous benthic foraminifera (Gavellina spp., Lenticulina spp.). Accordingly, the younger deposits at the Schattau section record an outer neritic to upper slope environment. Planctonic foraminifera indicate the Dicarinella asymetrica and the lowest Globotruncanita elevata biozone: The top of the Schattau section records the last appearance of the planktonic foraminifera Dicarinella asymetrica and

  20. 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 po

  1. Use of Amynthas gracilis (Oligochaeta, Megascolecidae) and Bougainvillea litter for rehabilitation of overexploited soils, in Campeche, Yucatan Peninsula, Mexico.

    Science.gov (United States)

    Huerta, Esperanza; Alonso Gongora, Erick

    2014-05-01

    Yucatan peninsula is one of the recent emerged lands in Mexico; where more of the soils have low organic matter content, and/or the organic horizon is thin (2-5cm). The industry of material extraction for construction purposes is well developed in Yucatan Peninsula, due to the fact of the calcareous material that can be obtained by the maternal rock. Therefore, the material extraction promotes the desertification of the areas, and soil erosion. Bougainvillea sp is a tropical and subtropical woody, evergreen, shrubby vine (Kobayashi et al. 2007), it has a wide range of distribution and it roots are superficial, what allows the plant to inhabit soils with a thin layer of soil organic matter. Earthworms as ecosystem engineers (Jones et al. 1994) can modify their environment, forming borrows and incorporation organic matter into the soil. The aim of this study was to rehabilitate soils without organic matter horizon by the use of earthworms and Bougainvillea litter. The study was developed at mesocosmos level in the laboratory of soils at El Colegio de la Frontera Sur, Unidad Campeche, Mexico. Individual of anecic earthworms were collected and reproduced previously, anecic worms can better incorporate organic matter in to the soil than epigeics or endogeics worms, in Mexican tropical terrestrial ecosystems, anecic worms are almost absent or scarce. In this study we used the exotic earthworm Amynthas gracilis (native in Taiwan),that used to inhabit banana plantations with low technology in southeast Mexico, as exotic has a wide range of tolerance to different amounts of soil organic matter and pH. Four treatments with 4 replicas were established: a) calcareous soil without organic matter horizon+earthworms+litter, b) calcareous soil with organic matter horizon+ earthworms+litter, c) calcareous soil without organic matter horizon+litter, d) calcareous soil with organic matter horizon+litter. After 60 days of study, we observed how earthworms developed successfully in

  2. Electrical Characteristics and Desorption Kinetics of Soil Boron

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    The status and activities of boron in soils were studied by the approach of electro-ultrafiltration (EUF). The samples of soils, including brown-red soil and calcareous alluvial soil, were collected from Hubei Province of China. The soil samples were incubated in saturated water and then their nutrients were ultrafiltrated with EUF equipment. Filtration and extraction were conducted in accordance with routine process, but fractions in anode and cathode were all collected. Analyses of B, K+, Mg2+, Ca2+, C1- and pH in fractions supposed that boron existed not only in a simple form of borate but also in ion-pair with cations partly in acidic soil,and borate was the primary form existing in the calcareous soil. In studying desorption kinetics with EUF,the boron content of Fractions 2~6 was accumulated, and the accumulative quantities were fit to time factors in three kinetic equations: the zero-order, first-order, and arabolic diffusion equations. Fit degree of the parabolic diffusion equation was the best, followed by the zero-order quation, and the first-order equation was the worst.

  3. Soil-geomorphology interactions and paleoclimatic implications of an ornithogenic soil toposequence on Rata Island, Fernando de Noronha Archipelago, South Atlantic

    Science.gov (United States)

    de Oliveira, Fábio Soares; Schaefer, Carlos Ernesto G. R.; Abrahão, Walter Antônio Pereira; Clemente, Eliane de Paula; Simas, Felipe Nogueira Bello

    2014-07-01

    The formation of highly phosphatized soils on sites of avian activity is a common feature of oceanic islands. We characterized a toposequence of phosphatic soils on Rata Island, to evaluate the soil genesis based on local topographic variations. For this purpose, four soils ranging from the upper hill down to the lowest landscape position on the island, representing a range of parent materials (basalt and calcareous sands), were analyzed. In the lowest landscape position a shallow Regosol was identified, strongly influenced by birds and marine sprays, developed on “karstified” Pleistocene calcarenites; the three other soils in the upper part of the toposequence are Ornithogenic Cambisols, ranging from a deep Cambisol profile on Basalt lava to intermediate Cambisols on mixed colluvial sediments of the basalt/calcareous. The lowermost Regosol is associated with a rugged landscape with strong calcarenite dissolution and karstification. The soil phosphatization is clearly an inherited process of the Late Quaternary age, when climate conditions were different. Initial weathering took place in the last interglacial period, under wetter conditions during which the Tertiary basalts were strongly weathered, leaving corestones in a saprolitic, oxidized mass. In the late Pleistocene, a gentle surface distributed these weathering products along the pediment slopes as colluvial materials, whereas in the coastal areas aeolian processes formed large sand dunes composed of reworked calcareous sands from marine sources during a time of very low sea level. During this time, widespread bird activity accounted for secondary apatite formation on the surface of calcareous oolites. Finally, the Holocene warming was accompanied by increasing sea level, enhanced tropical weathering, Fe and Al mobility and variscite formation superimposed on degraded Ca-phosphates, forming two phase phosphatic aggregates.

  4. Changes in metal availability, desorption kinetics and speciation in contaminated soils during repeated phytoextraction with the Zn/Cd hyperaccumulator Sedum plumbizincicola.

    Science.gov (United States)

    Li, Zhu; Jia, Mingyun; Wu, Longhua; Christie, Peter; Luo, Yongming

    2016-02-01

    Phytoextraction is one of the most promising technologies for the remediation of metal contaminated soils. Changes in soil metal availability during phytoremediation have direct effects on removal efficiency and can also illustrate the interactive mechanisms between hyperaccumulators and metal contaminated soils. In the present study the changes in metal availability, desorption kinetics and speciation in four metal-contaminated soils during repeated phytoextraction by the zinc/cadmium hyperaccumulator Sedum plumbizincicola (S. plumbizincicola) over three years were investigated by chemical extraction and the DGT-induced fluxes in soils (DIFS) model. The available metal fractions (i.e. metal in the soil solution extracted by CaCl2 and by EDTA) decreased greatly by >84% after phytoextraction in acid soils and the deceases were dramatic at the initial stages of phytoextraction. However, the decreases in metal extractable by CaCl2 and EDTA in calcareous soils were not significant or quite low. Large decreases in metal desorption rate constants evaluated by DIFS were found in calcareous soils. Sequential extraction indicated that the acid-soluble metal fraction was easily removed by S. plumbizincicola from acid soils but not from calcareous soils. Reducible and oxidisable metal fractions showed discernible decreases in acid and calcareous soils, indicating that S. plumbizincicola can mobilize non-labile metal for uptake but the residual metal cannot be removed. The results indicate that phytoextraction significantly decreases metal availability by reducing metal pool sizes and/or desorption rates and that S. plumbizincicola plays an important role in the mobilization of less active metal fractions during repeated phytoextraction.

  5. Thermoclastic and cryoclastic action on calcareous building stone: durability to artificial ageing

    Science.gov (United States)

    Germinario, Luigi; Andriani, Gioacchino Francesco; Laviano, Rocco

    2014-05-01

    Short and long-term climate changes are a critical factor of stone decay even in temperate Mediterranean areas, when the combined fluctuations of temperature and moisture lead to thermoclastism and cryoclastism. The effects of weathering are of particular concern in the conservation field, for the assessment of the vulnerability of outdoor-exposed stone materials in the historical built heritage. An example of this outline is Apulia, a region of southern Italy characterized by warm, dry summers and mild, rather rainy winters that can bring sub-zero temperatures; here, climate-driven decay can seriously affect the state of conservation of the local calcareous stone used in the monumental heritage, especially the most porous and softest materials. The dynamic behavior of the Apulian calcareous stone in response to thermo-hygrometric stresses was studied here by means of an artificial accelerated ageing test, focusing on a single local stone variety known as "pietra gentile". It is a fine-grained, soft and porous calcarenite, which is exploited in the Murge area from the outcrops of the "Calcare di Caranna" Fm. (late Campanian?-Maastrichtian). The quarrying activity is concentrated in the territory of Valle d'Itria and mainly of Ostuni, touristically known as "the White Town", where the stone is widely used for the sacred and civil architecture. The ageing test was programmed according to the typical climatic characteristics of the considered area, following the historical recordings by the official Apulian monitoring institute (Struttura di Monitoraggio Meteoclimatico, Centro Funzionale Regionale); in order to simulate the seasonal climatic changes, the extreme temperatures were considered, while the possible insolation effects for higher temperatures were also taken into account. So, samples of "pietra gentile" were subjected to 100 temperature cycles from 60 to -5 °C, in a climatic chamber with a maximum relative humidity of 60%. Before the ageing, the samples

  6. Calcareous nannofossil paleofluxes as proxy for pCO2 during the Aptian

    Science.gov (United States)

    Bottini, Cinzia; Erba, Elisabetta; Tiraboschi, Daniele

    2014-05-01

    The Aptian (~121 to ~113 Ma) has been characterized by super-greenhouse climate and profound environmental perturbations, including the early Aptian Oceanic Anoxic Event (OAE 1) a, an episode of widespread organic matter burial in oxygen-depleted oceans. The OAE 1a is thought to be related to the emplacement of the Ontong Java Plateau which probably introduced in the atmosphere a large amount of CO2 with consequent impact on biota, climate and ocean chemistry. The major perturbation of the carbon cycle is mirrored by the carbon isotopic record which shows a negative shift at the beginning of OAE 1a followed by a positive excursion which persisted also after the event. The aim of this study is to reconstruct variations in biogenic carbonate production of calcareous nannofossils through the Aptian in order to detect if and how it has been affected by high pCO2. Calcareous nannoplankton is an excellent proxy for reconstructing present and paste surface water conditions, being extremely sensitive to changes in physical and chemical conditions of the oceans (pH). Calcareous nannoplankton act both as biological and carbonate pump, thus changes in nannoplankton assemblages affect the organic and inorganic carbon cycles. This makes coccolithophores key-organisms for understanding the biological pump and adsorption of atmospheric CO2 into the oceans. Experiments on living coccolithophores indicates that coccolith type, abundance and degree of mineralization depend on chemical-physical-trophic conditions as well as on pCO2. Production of dwarf/malformed coccoliths has been documented in the geological record through OAE 1a. Here we present quantitative analyses of nannofossil micrite in thin sections, reconstructing nannofossil absolute abundances and calcite paleofluxes in three drill sites: the Cismon core (Northern Italy), Piobbico core (Central Italy) and DSDP Site 463 in the mid-Pacific Mountains. In these sites, nannofossil absolute abundances and paleofluxes show a

  7. Effect of the Soil pH on the Alkaloid Content of Lupinus angustifolius

    OpenAIRE

    Gisela Jansen; Hans-Ulrich Jürgens; Edgar Schliephake; Frank Ordon

    2012-01-01

    Field studies were conducted in growing seasons 2004, 2005, and 2010 to investigate the effect of different soil pH values on the alkaloid content in seeds of Lupinus angustifolius. Two-year experiments with eleven cultivars were carried out in acid soils with an average of pH=5.8 (Mecklenburg-Western Pomerania) and on calcareous soils with an average pH of 7.1 (Bavaria), respectively. In addition, in 2010, eight cultivars were grown in field experiments in soils with pH values varying betwee...

  8. Steel Slag as an Iron Fertilizer for Corn Growth and Soil Improvement in a Pot Experiment

    Institute of Scientific and Technical Information of China (English)

    WANG Xian; CAI Qing-Sheng

    2006-01-01

    The feasibility of steel slag used as an iron fertilizer was studied in a pot experiment with corn. Slag alone or acidified slag was added to two Fe-deficient calcareous soils at different rates. Results showed that moderate rates (10 and 20 g kg-1)of slag or acidified slag substantially increased corn dry matter yield and Fe uptake. Application of steel slag increased the residual concentration of ammonium bicarbonate-diethylenetriamine pentaacetic acid (AB-DTPA) extractable Fe in the soils. The increase of extractable Fe was usually proportional to the application rate, and enhanced by the acidification of slag. Steel slag appeared to be a promising and inexpensive source of Fe to alleviate crop Fe chlorosis in Fe-deficient calcareous soils.

  9. 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

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

    Science.gov (United States)

    Dedert, M.; Stoll, H. M.; Kroon, D.; Shimizu, N.; Kanamaru, K.; Ziveri, P.

    2012-05-01

    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 (productivity during ETM2. This high productivity phase is probably the result of enhanced nutrient supply either from land or from upwelling. The ion probe results show that calcareous nannoplankton productivity was not reduced by environmental conditions accompanying ETM2 at Site 1265, but imply an overall sustained productivity and potentially a small productivity increase during the extreme

  11. 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

  12. Creation of micro-topographic features: a new tool for introducing specialist species of calcareous grassland to restored sites?

    OpenAIRE

    Wagner, Markus; Bullock, James M.; Hulmes, Lucy; Hulmes, Sarah; Peyton, Jodey; Amy, Sam R.; Savage, Joanna; Tallowin, Jerry B.; Heard, Matthew S.; Pywell, Richard F.

    2016-01-01

    Questions: What types of pre-sowing disturbance are most suitable to establish specialist forbs of calcareous grassland at previously agriculturally improved restored sites? What impact does management regime have on post-establishment abundance-dynamics? Location: Pegsdon Hills, Bedfordshire, UK. Methods: We set up a 4-yr experiment using a split-plot design to combine pre-sowing disturbance treatments at sub-plot level (undisturbed control, glyphosate spraying, harrowing, and creati...

  13. Thermal Sprayed Aluminium for Subsea Heat Exchanger Surfaces : Effect of Temperature on Protection Current Requirement and Calcareous Development

    OpenAIRE

    Wilson, Håvard

    2014-01-01

    More and more equipment in the Oil and Gas Industry are being placed Subsea. Thisincludes subsea coolers with high internal temperatures. With high temperatures comewith challenges within material selection and corrosion. Traditional material choices like carbon steel and organic coatings with cathodic protection (CP) is not an option for subsea coolers. This is due to insulating properties to the organic coatings and the dense calcareous deposits which form on the surface of the steel.Therma...

  14. Soil warming affects soil organic matter chemistry of all density fractions of a mountain forest soil

    Science.gov (United States)

    Schnecker, Jörg; Wanek, Wolfgang; Borken, Werner; Schindlbacher, Andreas

    2016-04-01

    this C-rich calcareous forest soil.

  15. Calcareous nannofossil biostratigraphy of Sarcheshmeh and Sanganeh formations in the west of Kopet-Dagh Basin, Sheikh Section

    Directory of Open Access Journals (Sweden)

    Azam Mahanipour

    2015-05-01

    The Kopet-Dagh Basin is located in the north and north east of Iran, within the border triangle of Iran, Turkmenistan and Afghanistan. Sediments of Cretaceous age are well exposed in this basin. Sarcheshmeh and Sanganeh formations belong to the Cretaceous age in this basin and have the highest thickness in the west of the basin. Calcareous nannofossil investigation at the Sheikh section (in the west of the Kopet-Dagh Basin lead to the recognition of 84 species from 35 genera which are belonging to 16 families. According to the index calcareous nannofossils, the upper part of NC5 Zone (Watznaueria oblonga Zone, NC6 Zone (Chiastozygus litterarius Zone and the lower part of NC7a biozone (Rhagodiscus angustus Zone are recognized at the Sarcheshmeh Formation and NC7a biozone (Rhagodiscus angustus Zone is recognized at the basal part of Sanganeh Formation. Based on the calcareous nannofossils data, the age of Sarcheshmeh Formation is Late Barremian-early Late Aptian and the age of Sanganeh Formation is early Late Aptian -?Late Aptian.

  16. Upper Cenomanian – Lower Turonian (Cretaceous calcareous algae from the Eastern Desert of Egypt: taxonomy and significance

    Directory of Open Access Journals (Sweden)

    Ioan I. Bucur

    2010-04-01

    Full Text Available An assemblage of calcareous algae (dasycladaleans and halimedaceans is described from the Upper Cenomanian to Lower Turonian of the Galala and Maghra el Hadida formations (Wadi Araba, northern Eastern Desert, Egypt. The following taxa have been identified: Dissocladella sp., Neomeris mokragorensis RADOIČIĆ & SCHLAGINTWEIT 2007, Salpingoporella milovanovici RADOIČIĆ 1978, Trinocladus divnae RADOIČIĆ 2006, Trinocladus cf. radoicicae ELLIOTT 1968, and Halimeda cf. elliotti CONARD & RIOULT, 1977. Most of the species are recorded from the first time from Egypt. Three of the identified algae (T. divnae, S. milovanovici and H. elliotti also occur in Cenomanian limestones of the Mirdita zone, Serbia, suggesting a trans-Tethyan distribution of these taxa during the early Late Cretaceous. The abundance and preservation of the algae suggest an autochthonous occurrence which can be used for the characterization of the depositional environment. The recorded calcareous as well as the sedimentologic and palaeontologic context of the Galala Formation support an open-lagoonal (non-restricted, warm-water setting. The Maghra el Hadida Formation was mainly deposited in a somewhat deeper, open shelf setting. Calcareous algae (Halimeda cf. elliotti CONARD & RIOULT are restricted to one level in the uppermost Lower Turonian which indicates a brief return to shallow-water deposition after a significant deepening with maximum flooding during the early Early Turonian.

  17. Directed dispersal by rotational shepherding supports landscape genetic connectivity in a calcareous grassland plant.

    Science.gov (United States)

    Rico, Yessica; Holderegger, Rolf; Boehmer, Hans Juergen; Wagner, Helene H

    2014-02-01

    Directed dispersal by animal vectors has been found to have large effects on the structure and dynamics of plant populations adapted to frugivory. Yet, empirical data are lacking on the potential of directed dispersal by rotational grazing of domestic animals to mediate gene flow across the landscape. Here, we investigated the potential effect of large-flock shepherding on landscape-scale genetic structure in the calcareous grassland plant Dianthus carthusianorum, whose seeds lack morphological adaptations to dispersal to animals or wind. We found a significant pattern of genetic structure differentiating population within grazed patches of three nonoverlapping shepherding systems and populations of ungrazed patches. Among ungrazed patches, we found a strong and significant effect of isolation by distance (r = 0.56). In contrast, genetic distance between grazed patches within the same herding system was unrelated to geographical distance but significantly related to distance along shepherding routes (r = 0.44). This latter effect of connectivity along shepherding routes suggests that gene flow is spatially restricted occurring mostly between adjacent populations. While this study used nuclear markers that integrate gene flow by pollen and seed, the significant difference in the genetic structure between ungrazed patches and patches connected by large-flock shepherding indicates the potential of directed seed dispersal by sheep across the landscape.

  18. CALCAREOUS ALGAE FROM THE LOWER OLIGOCENE GORNJI GRAD BEDS OF NORTHERN SLOVENIA

    Directory of Open Access Journals (Sweden)

    DAVIDE BASSI

    2000-03-01

    Full Text Available This paper presents the first systematic account of calcareous algae from the limestones of the Lower Oligocene Gornji Grad beds of northern Slovenia. These bioclastic limestones are dominated by different coralline algal assemblages as well as corals, large and small benthic foraminifera as well as bivalves. The taxonomy and growth-forms of eleven species of seven non-geniculate coralline algal genera are described: Lithoporella, Neogoniolithon, Spongites, Lithothamnion, Mesophyllum, Sporolithon, Subterraniphyllum,. Additionally, the genera Polystrata (Peyssonneliaceae Halimeda (Halimedaceae, and Cymopolia (Dasycladaceae are present. The taxonomic interpretation of fossil coralline material in a manner consistent with generic and specific concepts currently in use for Recent material is, at present, difficult. In the absence of comparative studies on type material, only limited comparisons are possible, and in most cases definitive taxonomic conclusions cannot be reached. Most of the species designations are thus made following and open nomenclature, pending the rigorous taxonomic revision of historically established, fossil coralline algal species. The present study reveals a considerable variation of growth-form morphologies at both genus and species levels. This demonstrates the difficulties in using this feature as a diagnostic character in the identification of fossil coralline red algal taxa. 

  19. 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.

    2017-02-01

    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.

  20. Rock glacier development in the Northern Calcareous Alps at the Pleistocene-Holocene boundary

    Science.gov (United States)

    Moran, Andrew P.; Ivy Ochs, Susan; Vockenhuber, Christof; Kerschner, Hanns

    2016-11-01

    Relict rock glaciers provide information on past discontinuous permafrost and former mean annual air temperatures. A lack of records showing former permafrost distribution along the northern Alpine fringe prompted the investigation and numerical dating of a belt of relict rock glaciers in the Karwendel Mountains of the Northern Calcareous Austrian Alps. In two neighbouring cirques that were still glaciated during the early Younger Dryas, eleven 36Cl exposure ages from boulder surfaces were obtained. The ages imply the onset of rock glacier activity around ~ 12.3 ka with subsequent stabilization and permafrost melt out no later than ~ 10.1 ka. Hence, rock glacier formation coincided with glacier retreat in the cirques around the mid-Younger Dryas and continued into the early Holocene. As permafrost induced features, the rock glacier termini indicate the local past lower limit of discontinuous permafrost in open cirque floors at ~ 2000 m asl, which is around 400 m lower than during the mid-twentieth century at comparable locations in the Karwendel Mountains. Thus, a mean annual air temperature reduction of ~- 2.6 to - 3.8 °C relative to the mid-twentieth century is inferred. Based on a minimum glacier equilibrium line altitude in the cirques, a summer temperature reduction of less than - 2.6 to - 1.8 °C is shown, suggesting an increased seasonality at the time of rock glacier activity.

  1. LOWER CARNIAN FORAMINIFERS FROM THE TYPE LOCALITY OF THE CALCARE DELPREDIL (RAIBL GROUP, NORTHEASTERN ITALY

    Directory of Open Access Journals (Sweden)

    ROBERTO RETTORI

    1998-11-01

    Full Text Available Foraminiferal content from the type section of the Calcare del Predil, Early Carnian in age, is here firstly reported. Dolomites, dololimestones and blackish limestones alternate black shales, marls and marly limestones; in addition turbiditic deposits and debris flow consisting of calcirudites and thin to coarse calcarenites occur in the stratigraphical unit. The bottom of the Rio del Lago Formation was also investigated from a micropaleontological point of view. Nineteen taxa were classified; they are mainly represented by Aulotortinae Zaninetti, Lamelliconinae Zaninetti et al., Triadodiscinae Zaninetti, Turriglomininae Zaninetti and Ophthalmidiidae Wiesner. Furthermore, some Ammodiscidae Reuss, "Trochamminidae" Schwager, Piallinidae Rettori & Zaninetti, Duostominidae Brotzen and rare Lagenina Delage & Hérouard have been recorded. Undetermined encrusting foraminifers also occur. The specimens referable to the superfamily Involutinacea Btschli are dominant and represent the 4O% of the finely grained laminas inside the black limestones. The turriglominas occurring in the muddy lithotypes pertain to the morphogroup which is considered as typical of basinal environment. The occurrence almost constant in the micritic limestones of the ophthalmidiid Gsolbergella spiroloculiformis (Oravecz-Scheffer (few specimens leed to suggest this species as inhabitant basinal environment also. Two Julic species of the Austriacum zone are firstly reported from the Aon zone (Cordevolian Auct. and the suprageneric position of the genus Prorakusia di Bari & Laghi is also discussed. 

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

    Institute of Scientific and Technical Information of China (English)

    Amr Farouk Elhakim

    2015-01-01

    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 measure-ment/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.

  3. 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.

  4. Photoacoustic monitoring of water transport process in calcareous stone coated with biopolymers

    Science.gov (United States)

    May-Crespo, J.; Ortega-Morales, B. O.; Camacho-Chab, J. C.; Quintana, P.; Alvarado-Gil, J. J.; Gonzalez-García, G.; Reyes-Estebanez, M.; Chan-Bacab, M. J.

    2016-12-01

    Moisture is a critical control of chemical and physical processes leading to stone deterioration. These processes can be enhanced by microbial biofilms and associated exopolymers (EPS). There is limited current understanding of the water transport process across rocks covered by EPS. In the present work, we employed the photoacoustic technique to study the influence of three biopolymers (xanthan, microbactan and arabic gum) in the water transport process of two types of limestone rock of similar mineralogy but contrasting porosity. Both controls of RL (low porosity) and RP (high porosity) presented the higher values of water diffusion coefficient ( D) than biopolymer-coated samples, indicating that biopolymer layers slowed down the transport of water. This trend was steeper for RP samples as water was transported seven times faster than in the more porous rock. Important differences of D values were observed among samples coated by different biopolymers. Scanning electron microscopy and optical microscopy showed that surface topography was different between both types of rocks; adherence of coatings was seen predominantly in the less porous rocks samples. FTIR and NMR analysis showed the presence of pyruvate and acetate in microbactan and xanthan gum, suggesting their participation on adherence to the calcareous surfaces, sealing surface pores. These results indicate that water transport at rock interfaces is dependent on the chemistry of biopolymer and surface porosity. The implications for reduced water transport in stone conservation under the influence of biopolymers include both enhanced and lower deterioration rates along with altered efficiency of biocide treatment of epilithic biofilms.

  5. Influence of dissolved oxygen on the protectiveness and morphological characteristics of calcareous deposits with galvanostatic polarization

    Science.gov (United States)

    Li, Chengjie; Du, Min; Gao, Rongjie

    2017-04-01

    The influence of dissolved oxygen on calcareous deposits formed under galvanostatic polarization mode was studied. When the dissolved oxygen concentration was less than 7 mg L-1, the cathodic protection potential showed a plateau at the initial polarization, and then quickly shifted negatively. While the dissolved oxygen was more than 9 mg L-1, the potential shifted negatively in a linear form. After 168 h of polarization, the final protection potential shifted negatively with the decreasing dissolved oxygen concentration. The deposition progress was monitored by electrochemical impedance spectroscopy, and only one single loop was found in Nyquist diagram, indicating deposits of ineffective protectiveness precipitation under the experimental conditions. The protection factor of deposits increased with the decreasing dissolved oxygen concentration which was detected by linear polarization resistance technique. The cathodic electrochemical reaction could change very shortly from oxygen reduction to hydrogen evolution after cathodic protection under very low dissolved oxygen concentration, such as 1 mg L-1, resulting in the hydrogen bubbling from the metallic surface and the decrease of deposits protection factor. Observation by scanning electron microscopy and X-ray diffraction analysis demonstrated that the deposits were mainly of calcite under the experimental conditions, and that dissolved oxygen had no effect on the crystalline types of calcium carbonate.

  6. Life-cycle traits of Paraleucilla magna, a calcareous sponge invasive in a coastal Mediterranean Basin.

    Directory of Open Access Journals (Sweden)

    Caterina Longo

    Full Text Available The calcareous sponge Paraleucilla magna, originally observed along the Brazilian coast (Atlantic Ocean, is the only allochthonous invasive species of Porifera reported in the Mediterranean Sea. A 1-year investigation of the population dynamics and life-cycle of this exotic species in the Mar Piccolo di Taranto (southern Italy, central Mediterranean Sea has provided a good opportunity to test how environmental variations can influence its life-cycle and to ascertain what strategy can be adopted to successfully colonize a new environment. In the Mar Piccolo di Taranto, P. magna exhibits marked temporal changes in biomass. The studied specimens reproduce almost all year round, showing a seasonal pattern that peaks during warm months. This prolonged sexual activity allows P. magna to continuously produce young specimens, with repeated recruitment events taking place throughout the year, thus offsetting the seasonal mortality of adult specimens. This r-strategy enables the non-indigenous sponge to achieve a high degree of maintenance over relatively long periods (ten years at least.

  7. 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.

  8. Effect of land use change on soil properties and functions

    Science.gov (United States)

    Tonutare, Tonu; Kõlli, Raimo; Köster, Tiina; Rannik, Kaire; Szajdak, Lech; Shanskiy, Merrit

    2014-05-01

    For good base of sustainable land management and ecologically sound protection of soils are researches on soil properties and functioning. Ecosystem approach to soil properties and functioning is equally important in both natural and cultivated land use conditions. Comparative analysis of natural and agro-ecosystems formed on similar soil types enables to elucidate principal changes caused by land use change (LUC) and to elaborate the best land use practices for local pedo-ecological conditions. Taken for actual analysis mineral soils' catena - rendzina → brown soils → pseudopodzolic soils → gley-podzols - represent ca 1/3 of total area of Estonian normal mineral soils. All soils of this catena differ substantially each from other by calcareousness, acidity, nutrition conditions, fabric and humus cover type. This catena (representative to Estonian pedo-ecological conditions) starts with drought-prone calcareous soils. Brown (distributed in northern and central Estonia) and pseudopodzolic soils (in southern Estonia) are the most broadly acknowledged for agricultural use medium-textured high-quality automorphic soils. Dispersedly distributed gley-podzols are permanently wet and strongly acid, low-productivity sandy soils. In presentation four complex functions of soils are treated: (1) being a suitable soil environment for plant cover productivity (expressed by annual increment, Mg ha-1 yr-1); (2) forming adequate conditions for decomposition, transformation and conversion of fresh falling litter (characterized by humus cover type); (3) deposition of humus, individual organic compounds, plant nutrition elements, air and water, and (4) forming (bio)chemically variegated active space for soil type specific edaphon. Capacity of soil cover as depositor (3) depends on it thickness, texture, calcareousness and moisture conditions. Biological activity of soil (4) is determined by fresh organic matter influx, quality and quantity of biochemical substances and humus

  9. The status of phosphorus in Thai soils and P evaluation using EDTA-NaF extraction method

    Directory of Open Access Journals (Sweden)

    Toru Matoh

    2003-07-01

    Full Text Available Although the available P extracted by Bray II method in tropical soil is low, most of tropical plants can grow well. The objective of this study was to study P status and to evaluate the available P extracted by EDTA-NaF method. Top soil and sub soil of 10 dominant soil series in Thailand were analyzed for some chemical properties and characterization of the forms of phosphorus using EDTA-NaF extraction and successive phosphorus extraction by the modified Sekiya method. The soil total P concentration was 38-1137 mg P2O5 kg-1. The available Bray II-P was very low to high (1-76 mg P2O5 kg-1, and it approximated 0.17-12% of the total P. Iron and aluminum phosphates were the main fraction of inorganic P in acid soil, whereas Ca phosphates were in calcareous soils. Organic P content accounted for 33-67% and most of them were bound with Fe and Al in acid soils and Ca in calcareous soils. P extracted by EDTA-NaF reagent was obviously larger than that of Bray II reagent. The EDTA-NaF extracted P [high molecular weight organic P (HMWP+ inorganic P (EDTA ext Pi] was 7-46% and 1-6% of total P in acid soils and calcareous soils respectively. The EDTA ext Pi tended to be larger than HMWP except in Tk soil. The total amount of extracted P correlated well with Al-Pi and Fe-Pi which were the main fraction of inorganic P. It also correlated with HMWP, but HMWP did not correlate with organic P determine by ignition method and Ca-Po, Fe-Po and Al-Po. The EDTA-NaF method may be suitable for P evaluation in the soils which have high amounts of Fe-Pi, Al -Pi and organic P widely distributed in Thailand.

  10. Fourier transform infrared-attenuated total reflection nitrate determination of soil pastes using principal component regression, partial least squares, and cross-correlation.

    Science.gov (United States)

    Linker, Raphael; Kenny, Amit; Shaviv, Avi; Singher, Liviu; Shmulevich, Itzhak

    2004-05-01

    This paper investigates the use of Fourier transform infrared (FTIR) attenuated total reflectance (ATR) spectroscopy as a fast and simple way for direct determination of nitrate concentration in soil pastes, which would assist precision fertilizer placement and reduce nitrate pollution. Eight types of soils are investigated, with nitrate concentrations ranging from 0 to 1000 ppm-N. The spectral region around the nitrate band (1300-1550 cm(-1)) is analyzed by (1) principal component regression (PCR), (2) partial least squares (PLS), and (3) cross-correlation with reference libraries that include spectra of pure ions and/or soils. The main obstacle to accurate nitrate measurement appears to be an interfering band present in calcareous soils. This band, which may be due to carbonate, is located around 1450 cm(-1) and overlaps with the nitrate band centered around 1370 cm(-1). For non-calcareous soils, and in particular for light sandy agricultural soils, PLS and cross-correlation with a reference library containing only spectra of ions in water give similar results (about 8 ppm-N on dry soil basis), while PCR leads to slightly poorer results. When calcareous soils are included in the analysis, the prediction errors are about twice as large. In this case, the best results are obtained using PLS, followed by PCR, while cross-correlation with reference libraries leads to poorer results.

  11. Soil Physical Constraints on Intrinsic Biodegradation of Petroleum Vapors in a Layered Subsurface

    DEFF Research Database (Denmark)

    Kristensen, Andreas Houlberg; Henriksen, Kaj; Mortensen, Lars

    2010-01-01

    Intrinsic biodegradation of organic contaminants in the soil vadose zone depends on site-specific soil properties controlling biophysical and geochemical interactions within the soil pore space. In this study we evaluated the effect of soil texture and moisture conditions on aerobic biodegradation...... in a deep and highly layered vadose zone contaminated with petroleum hydrocarbons. Soil slurry experiments on benzene biodegradation were used for determining the relative potential for hydrocarbon biodegradation in 100 soil samples collected from 2-16 m below ground surface. Regardless of nutrient......-poor and calcareous subsoil conditions, the results showed a significant aerobic biodegradation potential. Average first-order rate constants (k1) ranged from 0 to 5 d-1 and varied significantly across soil types in the order sandy loam > fine sand > limestone. Within samples with high biodegradation potential, soil...

  12. 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.

  13. Evaluation of Estimated Daily Intake (EDI of Cadmium and Lead for Rice (Oryza sativa L. in Calcareous Soils

    Directory of Open Access Journals (Sweden)

    Ali Chamannejadian

    2013-04-01

    Full Text Available 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.

  14. Gaseous Loss of Nitrogen from Fertilizers Applied to Wheat on a Calcareous Soil in North China Plain

    Institute of Scientific and Technical Information of China (English)

    CAIGUIXIN; YANGZHEN; 等

    1998-01-01

    Nitrogen(N)losses from ammonium bicarbonate or urea applied to wheat and then followed immediately by irrigation were investigated.Ammonia volatilization was determined by a micrometeorological method (ammonia sampler),total N loss was estimated by the 15N mass balance method ,and denitrification loss was measured by the diference method(calculated from the difference between the total N loss and ammonia loss) and a direct method (measuring the emission of (N2+N2O)-15N).Total ammonia losses from ammonium bicarbonate and urea in 33 days were 8.7% and 0.9% of the applied nitrogen ,respectively.The corresponding total N losses were 21.6% and 29.5%,Apparent denitrification losses(by the difference method) were rather high,being 12.9% from ammonium bicarbonate and 28.6% from urea .However,no emission of (N2+N2O)-15N was detected using the direct method.

  15. Soil factors involved in the diversity and structure of soil bacterial communities in commercial organic olive orchards in Southern Spain.

    Science.gov (United States)

    Landa, B B; Montes-Borrego, M; Aranda, S; Soriano, M A; Gómez, J A; Navas-Cortés, J A

    2014-04-01

    Nowadays, there is a tendency in olive production systems to reduce tillage or keep a vegetative cover to reduce soil erosion and degradation. However, there is scarce information on the effects of different soil management systems (SMS) in soil bacterial community composition of olive groves. In this study, we have evaluated the effects of soil type and different SMS implemented to control weeds in the structure and diversity of bacterial communities of 58 soils in the two geographic areas that best represent the organic olive production systems in Spain. Bacterial community composition assessed by frequency and intensity of occurrence of terminal restriction profiles (TRFs) derived from terminal restriction fragment length polymorphism (T-RFLP) analysis of amplified 16S ribosomal deoxyribonucleic acid were strongly correlated with soil type/field site (Eutric/Calcaric) that differed mainly in soil particle size distribution and soil pH, followed by a strong effect of SMS, in that order. Canonical discriminant (CD) analysis of TRFs properly classified all of the olive orchard soils as belonging to their respective soil type or SMS. Furthermore, only a small set of TRFs were enough to clearly and significantly differentiate soil samples according to soil type or SMS. Those specific TRFs could be used as bioindicators to assess the effect of changes in SMS aimed to enhance soil quality in olive production systems.

  16. 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

  17. Calcareous palaeosols and temples in the floodplain of Thebes, Egypt: droughts and decisions

    Science.gov (United States)

    Graham, Angus; Hunter, Morag A.; Pennington, Benjamin T.; Strutt, Kristian D.

    2014-05-01

    The Egypt Exploration Society Theban Harbours and Waterscapes Survey (THaWS) works in the area around modern Luxor (Egypt), and investigates the extent to which the Egyptians manipulated the Nile and floodplain through canal and basin construction. A current focus of the project is to understand the relationship between the floodplain and a series of temples on the West Bank. A longstanding puzzle on the West Bank is why the temple of Amenhotep III (1390-1352 BCE) is not located in the same area as all the others. While 19 kings of the Egyptian New Kingdom (1550-1070 BCE) built their temples on the toe-slope of the limestone cliffs fronting onto the edge of the modern alluvium, Amenhotep's sits entirely on the modern floodplain. Egyptologists have suggested this was done to allow the inundation of the Nile to wash into the temple, symbolising and recreating the essential Egyptian cosmogony of the primeval mound. However, was it possible that a period of low Nile discharge enabled him to build on the alluvium whilst keeping the temple dry from the Nile floods? The project is testing this hypothesis through an interdisciplinary approach which provides focussed information on the development of the floodplain over historic time periods. It combines geophysical survey (Electrical Resistivity Tomography, Ground Penetrating Radar and magnetometry) with geoarchaeology using an Eijkelkamp hand auger and gouge auger with facies being dated using the stratigraphic sequence of ceramic fragments within them. Two fieldwork seasons have been carried out to date (Graham et al. 2012, 2013). Calcareous palaeosols c. 4m below the surface have been identified in three separate augers across a distance of 3 km on the West Bank floodplain, suggesting a period of low inundation levels / drought. At one of the locations an ancient surface appears to lie 0.3-0.4m above the calcisol. Ceramic fragments from this unit tentatively indicate a New Kingdom date. The strontium isotope record from

  18. Drought and detritivores determine leaf litter decomposition in calcareous streams of the Ebro catchment (Spain).

    Science.gov (United States)

    Monroy, Silvia; Menéndez, Margarita; Basaguren, Ana; Pérez, Javier; Elosegi, Arturo; Pozo, Jesús

    2016-12-15

    Drought, an important environmental factor affecting the functioning of stream ecosystems, is likely to become more prevalent in the Mediterranean region as a consequence of climate change and enhanced water demand. Drought can have profound impacts on leaf litter decomposition, a key ecosystem process in headwater streams, but there is still limited information on its effects at the regional scale. We measured leaf litter decomposition across a gradient of aridity in the Ebro River basin. We deployed coarse- and fine-mesh bags with alder and oak leaves in 11 Mediterranean calcareous streams spanning a range of over 400km, and determined changes in discharge, water quality, leaf-associated macroinvertebrates, leaf quality and decomposition rates. The study streams were subject to different degrees of drought, specific discharge (Ls(-1)km(-2)) ranging from 0.62 to 9.99. One of the streams dried out during the experiment, another one reached residual flow, whereas the rest registered uninterrupted flow but with different degrees of flow variability. Decomposition rates differed among sites, being lowest in the 2 most water-stressed sites, but showed no general correlation with specific discharge. Microbial decomposition rates were not correlated with final nutrient content of litter nor to fungal biomass. Total decomposition rate of alder was positively correlated to the density and biomass of shredders; that of oak was not. Shredder density in alder bags showed a positive relationship with specific discharge during the decomposition experiment. Overall, the results point to a complex pattern of litter decomposition at the regional scale, as drought affects decomposition directly by emersion of bags and indirectly by affecting the functional composition and density of detritivores.

  19. Effects of flow scarcity on leaf-litter processing under oceanic climate conditions in calcareous streams.

    Science.gov (United States)

    Martínez, Aingeru; Pérez, Javier; Molinero, Jon; Sagarduy, Mikel; Pozo, Jesús

    2015-01-15

    Although temporary streams represent a high proportion of the total number and length of running waters, historically the study of intermittent streams has received less attention than that of perennial ones. The goal of the present study was to assess the effects of flow cessation on litter decomposition in calcareous streams under oceanic climate conditions. For this, leaf litter of alder was incubated in four streams (S1, S2, S3 and S4) with different flow regimes (S3 and S4 with zero-flow periods) from northern Spain. To distinguish the relative importance and contribution of decomposers and detritivores, fine- and coarse-mesh litter bags were used. We determined processing rates, leaf-C, -N and -P concentrations, invertebrate colonization in coarse bags and benthic invertebrates. Decomposition rates in fine bags were similar among streams. In coarse bags, only one of the intermittent streams, S4, showed a lower rate than that in the other ones as a consequence of lower invertebrate colonization. The material incubated in fine bags presented higher leaf-N and -P concentrations than those in the coarse ones, except in S4, pointing out that the decomposition in this stream was driven mainly by microorganisms. Benthic macroinvertebrate and shredder density and biomass were lower in intermittent streams than those in perennial ones. However, the bags in S3 presented a greater amount of total macroinvertebrates and shredders comparing with the benthos. The most suitable explanation is that the fauna find a food substrate in bags less affected by calcite precipitation, which is common in the streambed at this site. Decomposition rate in coarse bags was positively related to associated shredder biomass. Thus, droughts in streams under oceanic climate conditions affect mainly the macroinvertebrate detritivore activity, although macroinvertebrates may show distinct behavior imposed by the physicochemical properties of water, mainly travertine precipitation, which can

  20. The impact of the Maastrichtian cooling on the marine nutrient regime -- Evidence from midlatitudinal calcareous nannofossils

    Science.gov (United States)

    Linnert, Christian; Engelke, Julia; Wilmsen, Markus; Mutterlose, Jörg

    2016-06-01

    The latest Campanian-earliest Maastrichtian interval is well known as a period of intense climate cooling. This cooling caused a distinctive bipolar biogeographic distribution of calcareous nannofossil assemblages: High-latitude settings were dominated by newly evolving endemic taxa, former cosmopolitan species disappeared at the same time, and equatorial communities experienced an invasion of cool water taxa. The impact of this cooling on northern midlatitude assemblages is, however, less well known. In order to overcome this gap we studied the Kronsmoor section (northwest Germany). This section provides a continuous upper Campanian -- lower Maastrichtian succession with moderately to well preserved nannofossils. Uppermost Campanian assemblages are dominated by Prediscosphaera cretacea; other common taxa include Prediscosphaera stoveri, Watznaueria barnesiae, and Micula staurophora. The lower Maastrichtian is characterized by lower numbers of P. cretacea and frequent Kamptnerius magnificus, Arkhangelskiella cymbiformis, and Cribrosphaerella ehrenbergii. These changes reflect, in part, the Campanian-Maastrichtian boundary cooling since some successful taxa (e.g., K. magnificus) are related to cool surface waters. Other shifts in the nannofossil communities were perhaps the result of a changing nutrient regime. Stronger latitudinal gradients may have increased wind velocities and thus the eolian input of ferruginous dust required by N-fixing bacteria. The enhanced high-latitude deep water formation probably changed the bottom water environment in disfavor of denitrificating organisms. A decline of chemical weathering and fluviatile transport may have reduced the amount of bioavailable phosphate. These processes led to an increased nitrate and a decreased phosphate content shifting the nutrient regime from nitrate toward phosphate limitation.

  1. [Gastropods associated with the calcareous alga Halimeda opuntia (Udoteaceae) in Puerto Rico].

    Science.gov (United States)

    García-Ríos, Cedar I; Soto-Santiago, Francisco J; Colón-Rivera, Ricardo J; Medina-Hernández, Javier R

    2008-12-01

    Gastropod communities associated with the calcareous green alga Halimeda opuntia are described and compared for two Puerto Rico coral reefs: one in the northeast with front tradewinds (windward zone) and one in the southwest (leeward zone). We analyzed the content of 21 lots (2432 g) of H. opuntia from leeward zone and 15 lots (2448 g) from the windward zone. In total we recovered 526 gastropods (prosobranchs) classified in 54 taxa. Thirteen species of gastropods represented 79.6% of the community. Differences between species richness and mean density values were not significant (p > 0.100). Forty species were identified from leeward and thirty one (31) species from windward. Gastropod mean density was 13.9/100 g of algae in leeward and 7.6/100 g in windward. Significant differences were found for the Simpson Diversity Index (0.91 in the leeward and 0.82 in the windward community; t = 3.44, alpha = 0.005). We found no correlation between the weight of the algae and the frequency of the gastropods (R2 = 0.0893 in leeward, 0.0249 windward and 0.0923 for both). The relationship between species composition in lots of windward and leeward study sites was explored via polar ordination and no segregation was found. When compared, the gastropod communities found in H. opuntia collected in coral reefs in Puerto Rico were more similar within them than any other communities found in other genera of seaweed and in other environments. Our results agree with the hypothesis that H. opuntia offers the interstitial community a protected microhabitat from water movement impact. H. opuntia creates more homogenous conditions than those of the habitat where we found the algae.

  2. 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

  3. A Neogene seawater sulfur isotope age curve from calcareous pelagic microfossils

    Science.gov (United States)

    Burdett, James W.; Arthur, Michael A.; Richardson, Mark

    1989-09-01

    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 34S of seawater has decreased about 2.5‰ over the past 25 m.y. and that most of the decrease has occurred over the past 5 m.y., parallelling a decrease in the δ 13C 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 O 2.

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

    Science.gov (United States)

    Voigt, Oliver; Wülfing, Eilika; Wörheide, Gert

    2012-01-01

    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 desperate need of a

  5. Phase relations and dehydration behaviour of calcareous sediments at P-T conditions of accretionary wedge systems

    Science.gov (United States)

    Massonne, H.-J.

    2009-04-01

    In a recent paper (Eur. J. Mineral. 20), Massonne and Willner (2008) presented P-T pseudosections for common rocks involved in accretionary wedge systems and argued that the dehydration of psammopelitic rocks could be an essential process for the formation of these systems. These authors assumed that this dehydration process leads to softening of the sedimentary cover of oceanic crust during early subduction so that this material can be scraped off the basic crust. Since many accretionary wedge systems contain metamorphosed calcareous sediments it was tested which influence carbonates, ignored by Massonne and Willner (2008), could have on the dehydration behaviour of these sediments. For this purpose, P-T pseudosections were calculated for a calcareous greywacke and a marly limestone in the system Na-Ca-K-Fe-Mn-Mg-Al-Si-Ti-C-O-H with the PERPLEX software package (Connolly, 2005) for the pressure-temperature range 1-25 kbar and 150-450°C. In addition to the thermodynamic data and solid solution models already used by Massonne and Willner (2008), a newly created quaternary (Ca-Mn-Mg-Fe2+) solid solution model was applied to carbonate with calcite structure together with an existing dolomite-ankerite model. Aragonite was considered as a pure phase. The Mn end-member was added to the previously used stilpnomelane model in order to calculate the P-T conditions of garnet formation at high pressure. Along a low geotherm of 10-12°C/km, the dehydration behaviour of a calcareous greywacke resembles that of the previously studied psammopelite. However, the relevant dehydration event (release of about 1 wt% H2O) occurs in the temperature interval 270-330°C and, thus, at temperatures about 30°C higher than in an ordinary psammopelite. The calculated compositions of fluids generated at low geotherms (

  6. CO(2-driven ocean acidification alters and weakens integrity of the calcareous tubes produced by the serpulid tubeworm, Hydroides elegans.

    Directory of Open Access Journals (Sweden)

    Vera Bin San Chan

    Full Text Available As a consequence of anthropogenic CO(2-driven ocean acidification (OA, coastal waters are becoming increasingly challenging for calcifiers due to reductions in saturation states of calcium carbonate (CaCO(3 minerals. The response of calcification rate is one of the most frequently investigated symptoms of OA. However, OA may also result in poor quality calcareous products through impaired calcification processes despite there being no observed change in calcification rate. The mineralogy and ultrastructure of the calcareous products under OA conditions may be altered, resulting in changes to the mechanical properties of calcified structures. Here, the warm water biofouling tubeworm, Hydroides elegans, was reared from larva to early juvenile stage at the aragonite saturation state (Ω(A for the current pCO(2 level (ambient and those predicted for the years 2050, 2100 and 2300. Composition, ultrastructure and mechanical strength of the calcareous tubes produced by those early juvenile tubeworms were examined using X-ray diffraction (XRD, Fourier transform infrared spectroscopy (FT-IR, scanning electron microscopy (SEM and nanoindentation. Juvenile tubes were composed primarily of the highly soluble CaCO(3 mineral form, aragonite. Tubes produced in seawater with aragonite saturation states near or below one had significantly higher proportions of the crystalline precursor, amorphous calcium carbonate (ACC and the calcite/aragonite ratio dramatically increased. These alterations in tube mineralogy resulted in a holistic deterioration of the tube hardness and elasticity. Thus, in conditions where Ω(A is near or below one, the aragonite-producing juvenile tubeworms may no longer be able to maintain the integrity of their calcification products, and may result in reduced survivorship due to the weakened tube protection.

  7. The influence of the soil on spring and autumn phenology in European beech.

    Science.gov (United States)

    Arend, Matthias; Gessler, Arthur; Schaub, Marcus

    2016-01-01

    Tree phenology is a key discipline in forest ecology linking seasonal fluctuations of photoperiod and temperature with the annual development of buds, leaves and flowers. Temperature and photoperiod are commonly considered as main determinants of tree phenology while little is known about interactions with soil chemical characteristics. Seedlings of 12 European beech (Fagus sylvatica L.) provenances were transplanted in 2011 to model ecosystems and grown for 4 years on acidic or calcareous forest soil. Spring bud burst and autumnal leaf senescence were assessed in the last 2 years, 2013 and 2014, which were characterized by contrasting annual temperatures with a very warm spring and autumn in 2014. In 2013, spring bud burst and autumnal leaf senescence were advanced on acidic soil with a greater effect on leaf senescence. Hence, the vegetation period 2013 was shorter on this soil type compared with that on calcareous soil. In 2014, a similar soil effect was observed for spring bud burst while autumnal leaf senescence and the length of the vegetation period were not affected, probably due to interferences with the overall extension of the vegetation period in this exceptionally warm year. A different soil responsiveness was observed among the provenances with early bursting or senescing provenances being more sensitive than late bursting or senescing provenances. The findings of this study highlight the soil as an ecologically relevant factor in tree phenology and might help explain existing uncertainties in current phenology models.

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

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    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

  9. Fate and Transport of Road Salt During Snowmelt Through a Calcareous Fen: Kampoosa Bog, Stockbridge, Massachusetts

    Science.gov (United States)

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

    2007-12-01

    Kampoosa Bog is the largest and most ecologically diverse calcareous lake-basin fen in Massachusetts. Situated within a 4.7 km2 drainage basin, the open fen (approx. 20 acres) consists of a floating mat of sedges (incl. Carex aquatilis and Cladium mariscoides) that overlie peat and lake clay deposits. Mineral weathering of marble bedrock within the drainage basin supplies highly alkaline ground and surface waters to the fen basin. The natural chemistry has been greatly altered by road salt runoff from the Massaschusetts Turnpike, and in question is whether disturbance from the Turnpike and a gas pipline has facilitated aggressive growth by the invasive species Phragmites australis. Considered to be one of the most significant rare species habitats in the state, Massachusetts has designated Kampoosa Bog an Area of Critical Environmental Concern, and a committee representing several local, regional, and state agencies, organizations, and citizens manages the wetland. The purpose of this study is to characterize the hydrologic and chemical response of the wetland during snowmelt events to understand the fate and movement of road salt (NaCl). Concentrations of Na and Cl in the fen groundwater are greatest close to the Turnpike. Concentrations decrease with distance downstream but are still greatly elevated relative to sites upstream of the Turnpike. During snowmelt events, the fen's outlet shows a sharp rise in Na and Cl concentrations at the onset of melting that is soon diluted by the added meltwater. The Na and Cl flux, however, is greatest at peak discharge, suggesting that high-flow events are significant periods of export of dissolved salts from the fen. Pure dissolution of rock salt produces an equal molar ratio between Na and Cl, and sodium and chloride imbalances in stream and ground waters suggest that ~20% of the Na is stored on cation exchange sites within the peat. The largest imbalances between Na and Cl occur deeper within the peat, where the peat is

  10. Oxygen and carbon isotope records of calcareous nannofossils for the past 1 Ma in the southern South China Sea

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Oxygen and carbon isotopic analyses have been carried out on calcareous nannofossils from ODP Site 1143 in the southern South China Sea. The results demonstrate that the δ18O values of calcareous nannofossils for the past 1 Ma vary systematically with those of planktonic and benthic foraminifera from the same site. But the average δ18O value of nannofossils is 1.869‰ higher than that of planktonic foraminifera, and is 3.855‰ lower than that of benthic foarminifera. There are systematic differences between the δ13C values of nannofossils, planktonic foarminifera and benthic foraminifera. The average δ13C of nannofossils is 0.756‰ higher than that of benthic foraminifera, and is 0.460‰ lower than that of planktonic foraminifera. The δ13C values of nannofossils exhibit a significant positive shift beginning near isotope stage 14 and lasting until stage 8. This study also finds that there is a close ralationship between the δ13C of nannofossils and the percentage of Florisphaera profunda. This implies that the δ13C of nannofossils can be used as an indicator of sea water surface paleoproductivity.

  11. Calcareous microfossil biostratigraphy of the uppermost cenozoic formations distributed in the coast of the Japan Sea (Part 1). Niigata area

    Energy Technology Data Exchange (ETDEWEB)

    Sato, Tokiyuki; Takayama, Toshiaki; Kato, Michio; Kudo, Tetsuro

    1987-05-01

    Eleven calcareous nannofossil biohorizons were established in the Quaternary sequences at six sites drilled in the Northeast Atlantic Ocean during DSDP-IPOD Leg 94. Correlation of these biohorizons with the magnetostratigraphy was established and ages of all datums were estimated. As the results, the applicability to the Japan Sea sedimentary basin was confirmed. The Nishiyama and Haizume formations distributed in the Oginome area, near the type locality of the Hashizume Formation in Niigata district were surveyed as the representative formation of the uppermost Cenozoic formation distributed in the coast of the Japan Sea; and five calcareous nannofossil biohorizons were recognized. Based on the above results of DSDP-IPOD, the middle Nishiyama through the Hashizume formations were Peistocene in age and could be correlated with interval between the Olduvai and Jaramillo events of the magnetostratigraphy. This age assignment agreed neither with magnetostratigraphic interpretations nor with fission track datings which were obtained in the Oguni area 25 km south of the present area. (23 refs, 11 figs)

  12. 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.

  13. CALCAREOUS PLANKTON BIOSTRATIGRAPHY AND AGE OF THE MIDDLE MIOCENE DEPOSITS OF LONGANO FORMATION (EASTERN MATESE MOUNTAINS, SOUTHERN APENNINES

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    FABRIZIO LIRER

    2005-03-01

    Full Text Available The integrated calcareous plankton biostratigraphy (planktonic foraminifera and calcareous nannofossils and an accurate fieldwork, allowed us the reconstruction of the sedimentary evolution of the Longano Formation (Orbulina Marls. In particular the correlation between the bioevents recognised in the Orbulina Marls sequence and those recorded in astronomically calibrated Middle Miocene sections, offered the possibility to date the passage from the shallow-water Cusano Formation to the deep-water deposits of the Longano Formation at about 13.21 Ma and the successive onset of terrigenous deposits of the Pietraroia Formation at 10.54 Ma. In addition, an high resolution study of the terrigenous sequence, showed that this sedimentary event is not abrupt but it is characterised by a progressive increase, bed by bed, of the siliciclastic fraction up to the deposition of the sandstones. The recognition in all the studied sections of the base of the first Acme (AB1 of Paragloborotalia siakensis dated at 13.21 Ma, just above the phosphate-rich interval (this interval marks the transition between Cusano and Longano Formations, proved that the transgression which led to the deposition of the Orbulina Marls was synchronous in all the south-eastern Matese Mountains. 

  14. Intra-aggregate CO2 enrichment: a modelling approach for aerobic soils

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    H. Schack-Kirchner

    2012-10-01

    Full Text Available CO2 concentration gradients inside soil aggregates, caused by the respiration of soil microorganisms and fungal hyphae, might lead to variations in the soil solution chemistry on a mm-scale, and to an underestimation of the CO2 storage. But, up to now, there seems to be no feasible method for measuring CO2 inside natural aggregates with sufficient spatial resolution. We combined a one-dimensional model for gas diffusion in the inter-aggregate pore-space with a cylinder diffusion model, simulating the consumption/production and diffusion of O2 and CO2 inside soil aggregates with air- and water-filled pores. Our model predicts that for aerobic respiration (respiratory quotient = 1 the intra-aggregate increase in the CO2 partial pressure can never be higher than 0.9 kPa for siliceous, and 0.08 kPa for calcaric aggregates, independent of the level of water-saturation. This suggests that only for siliceous aggregates CO2 produced by aerobic respiration might cause a high small-scale spatial variability in the soil solution chemistry. In calcaric aggregates, however, the contribution of carbonate species to the CO2 transport should lead to secondary carbonates on the aggregate surfaces. As regards the total CO2 storage in aerobic soils, both siliceous and calcaric, the effect of intra-aggregate CO2 gradients seems to be negligible. To assess the effect of anaerobic respiration on the intra-aggregate CO2 gradients, the development of a device for measuring CO2 on a mm-scale in soils is indispensable.

  15. Chemical denudation rates of a small torrential catchment in the Northern Calcareous Alps

    Science.gov (United States)

    Trost, Georg; Robl, Jörg; Hauzenberger, Christoph; Hilberg, Sylke; Schmidt, Rudolf

    2016-04-01

    Our understanding on the decay of alpine landscapes and the pace of landscape adjustment to climatic or tectonic changes rely on catchment wide erosion rates. In general, these data stem from cosmogenic isotope dating of quartz grains and are therefore only applicable at catchments providing suitable bedrock. However, denudation caused by the dissolution of rocks is not explicitly considered by this method. In the Northern Calcareous Alps (NCA) crystalline rocks are missing and intensive karstification suggests that chemical denudation is an important player for destroying topography. In this study we present chemical denudation rates derived from measuring the dissolved load of an alpine catchment located in the country of Salzburg, Austria. The catchment has a drainage area of about 7 km2 and is predominantly covered by limestone rich glacial deposits and carbonatic rocks as characteristic for the NCA. In order to obtain catchment wide chemical denudation rates we have integrated discharge time series that where measured by a permanent water gauge of the Austrian Service for Torrent and Avalanche Control to compute the total discharge of the investigated catchment over a period of one year. During the same period samples were taken at several campaigns to consider variations of the dissolved load. Samples were taken at high and low run-off conditions to study the effect of precipitation and at different locations along the tributaries to account for lithological variations of the river beds on the dissolved load. The concentrations of various cations in water samples were measured by the ICP-MS facility at the University of Graz. For the investigation period of one year 3.02 ∗ 106m3 of discharge was measured at the catchment outlet. The summed cation-concentration is varying between about 85 mg/l for dry-conditions and 75 mg/l for rainy-conditions at the gauge and consists predominantly of Ca+ cations. Based on the total discharge of the river integrated over a

  16. Changes in the properties of solonetzic soil complexes in the dry steppe zone under anthropogenic impacts

    Science.gov (United States)

    Lyubimova, I. N.; Novikova, A. F.

    2016-05-01

    Long-term studies of changes in the properties of solonetzic soil complexes of the dry steppe zone under anthropogenic impacts (deep plowing, surface leveling, irrigation, and post-irrigation use) have been performed on the Privolzhskaya sand ridge and the Khvalyn and Ergeni plains. The natural morphology of solonetzic soils was strongly disturbed during their deep ameliorative plowing. At present, the soil cover consists of solonetzic agrozems (Sodic Protosalic Cambisols (Loamic, Aric, Protocalcic)), textural (clay-illuvial) calcareous agrozems (Eutric Cambisols (Loamic, Aric, Protocalcic)), agrosolonetzes (Endocalcaric Luvisols (Loamic, Aric, Cutanic, Protosodic), agrochestnut soils (Eutric Cambisols (Siltic, Aric)), and meadowchestnut soils (Haplic Kastanozems). No features attesting to the restoration of the initial profile of solonetzes have been found. The dynamics of soluble salts and exchangeable sodium differ in the agrosolonetzes and solonetzic agrozems. A rise in pH values takes place in the middle part of the soil profiles on the Khvalyn and Ergeni plains.

  17. Evolution and Production of Calcareous Nannoplankton During the Cretaceous as Proxies of LIP-induced Oceanic Fertilization, Acidification and Anoxia

    Science.gov (United States)

    Erba, E.; Bottini, C.; Tiraboschi, D.

    2008-12-01

    Through the Phanerozoic, biota have been intimately linked to Earth's degassing inducing major changes in composition and structure of the ocean-atmosphere system. Emplacement of large igneous provinces (LIPs) has been the primary natural source of atmCO2 with dramatic consequences on climate and ecosystems. During the mid-Cretaceous the Ontong Java-Manihiki and Caribbean Plateaus LIPs are recognized as responsible of pCO2 as high as 2000 ppm. Coeval biocalcification crises occurred in pelagic and neritic settings, suggesting a causal link between high concentrations of carbon dioxide and drops in benthic and planktonic calcifiers' efficiency. Within the oceanic biosphere, calcareous nannoplankton play a key-role as: (1) is widespread and consists of cosmopolitan and endemic taxa; (2) has a 220 My-long evolutionary history; (3) is one the most effective calcite producers; (4) is relevant for the C cycle; (5) is extremely sensitive to environmental variations. Diversity pulses of Cretaceous calcareous nannoplankton are grossly coeval with LIP construction, climate and sea-level changes, variations in ocean structure and composition, suggesting that evolutionary patterns are closely linked to environmental modifications. We explored time-intervals of LIP formation marked by nannoplankton adaptation/evolution, quantifying evolutionary rates, species richness, abundance, calcite production and morphometry. High-resolution investigations of the initial phase of both early Aptian oceanic anoxic event (OAE) 1a and latest Cenomanian OAE 2 pointed out major evolutionary changes, decreases in heavily calcified nannoliths and occurrence of dwarf coccoliths. Nannoplankton calcification crises and dwarfism is here interpreted as forced by rapidly increasing pCO2 during formation of the Ontong Java-Maniniki and Caribbean Plateaus. Alternatively or concurrently, calcification crash and dwarfism might result from enhanced fertility associated to OAE1a and OAE2 regardless of ocean

  18. Reconsideration of the so-called Oligocene fauna in the asphaltic deposits of Buton (Malay Archipelago) — 2. Young-Neogene Foraminifera and calcareous Algae

    NARCIS (Netherlands)

    Keyzer, F.G.

    1952-01-01

    Miopliocene marls from the island of Buton yield a large marine foraminiferal fauna and some calcareous algae. Three-hundred and thirthy-three species have been identified. Two genera, twenty-three species and four varieties are described as new. The existence of mud-volcanoes in young neogene time

  19. Two new species of calcareous sponges (Porifera: Calcarea) from the deep Antarctic Eckstrom 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...

  20. 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...

  1. 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,

  2. How a Sphagnum fuscum-dominated bog changed into a calcareous fen : the unique Holocene history of a Slovak spring-fed mire

    NARCIS (Netherlands)

    Hajkova, Petra; Grootjans, A. B.; Lamentowicz, Mariusz; Rybnickova, Eliska; Madaras, Mikulas; Opravilova, Vera; Michaelis, Dierk; Hajek, Michal; Joosten, Hans; Wolejko, Leslaw; Rybníčková, Eliška; Madaras, Mikuláš; Opravilová, Věra; Wołejko, Lesław; Hajkova, T.

    2012-01-01

    In general, mires develop by autogenic succession from more groundwater-fed to more rainwater-fed. This study from a calcareous mire in the West Carpathians (Slovakia) describes a similar development in the Early Holocene, followed by a reverse development in the Middle and Late Holocene. Pollen, ma

  3. CHANGE OF BIOLOGICAL ACTIVITY OF RENDZINA SOILS OF WESTERN CAUCASUS AT POLLUTION BY ZINC, CADMIUM, MOLYBDENUM AND SELENIUM

    Directory of Open Access Journals (Sweden)

    Tatlok D. R.

    2015-02-01

    Full Text Available Rendzina soils are very widespread in the Caucasus. Because of their ecological and genetic characteristics Rendzina has significant buffering capacity to chemical pollution. The object of investigation was calcareous leached soil. Location selection - Azishskaya ridge on the border of the Republic of Adygea and the Krasnodar region. As pollutants, we have selected Zn, Cd, Mo, Se, since soil contamination with these elements in the south of Russia is not uncommon. Contamination of zinc, cadmium, molybdenum and selenium causes deterioration in the biological properties of calcareous soils of the Western Caucasus. We have investigated the toxicity of the elements formed following series due to their influence on Rendzina soils: Zn> Se> Cd> = Mo. The study attempted to analyze the entire range of concentrations of the examined elements in the soil, currently occurring in nature. In most cases, all the investigated substances registered direct correlation between the concentration of the pollutant in the soil and the degree of reduction of biological indicators. The activity of catalase and dehydrogenase cellulolytic ability, plenty of bacteria of the genus Azotobacter, length of roots of radish can be used to monitor, diagnose and regulation of chemical pollution of soil Zn, Cd, Mo, Se

  4. Evaluation of Soil Labile Phosphorus Using a Double—Labeling (32P and 33P) Technique

    Institute of Scientific and Technical Information of China (English)

    WANGGUANG-HUO

    1992-01-01

    Isotopic exchangeability of phosphorus in four Chinese soils with and without P application was studied by 32P and 33P double-labeling technique in relation to routine chemical extractions.The results showed that Bray-I and Bray-Ⅱ reagents could extract most of the fast exchangeable P.Not all of the Olsen-P belonged to fast exchangeable P,but it was about the same quantity of fast exchangeable P in a calcareous soil and a neutral soil without P application.Sequential fractionation of the soil phosphorus showed that most of the added radioisotopes in high P fixation red soils were tightly held by iron and aluminium oxides,which could be totally extracted only by 0.1M NaOH solution.In the neutral and calcareous soils most of the radioisotopes added were loosely held on the surface of soil particles and could be extracted by anion exchange resin.Phosphate application increased the resin-P fraction significantly for all the soils studied.

  5. Calcareous nannofossil assemblages of the upper Miocene to Pliocene Shimajiri Group on Okinawa-jima, Ryukyu Islands, southwestern Japan

    Science.gov (United States)

    Imai, Ryo; Sato, Tokiyuki; Iryu, Yasufumi

    2017-03-01

    We investigated the calcareous nannofossil biostratigraphy and paleoceanography of the Shimajiri Group in two exploratory wells (depths, 1243 and 1800 m) drilled on southern Okinawa-jima, Ryukyu Islands, southwestern Japan. Three late Miocene to Pliocene datum planes were identified: the first occurrence of Amaurolithus spp. (7.42 Ma), the last occurrence of Discoaster quinqueramus (5.59 Ma), and the first occurrence of Ceratolithus rugosus (5.12 Ma). These datum planes were also identified in two other deep wells on southern Okinawa-jima. Nutrient levels (reconstructed from the relative abundances of small Reticulofenestra spp., and the relative abundances of Discoaster spp. plus Sphenolithus abies) suggest that deposition of the Shimajiri Group (<8.29-3.50 Ma) occurred under conditions of increasing eutrophication. The eutrophication was likely caused by shallowing of the sedimentary basin, but a stepwise shift was associated with an abrupt eutrophication event that occurred in the northwestern Pacific Ocean at 5 Ma.

  6. 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.

  7. 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.

  8. Age of the Tananwan Formation in Northern Taiwan: A Reexamination of the Magnetostratigraphy and Calcareous Nannofossil Biostratigraphy

    Directory of Open Access Journals (Sweden)

    Chorng-Shern Horng

    2014-01-01

    Full Text Available Over the past two decades, the succession strata of the Tananwan Formation exposed horizontally on the Linkou Tableland in northwestern Taiwan has been either dated to a short time interval of 0.9 - 0.7 Ma or assigned to a vague long period within the Matuyama Epoch covering probably both the Olduvai and Jaramillo normal events. In this study, a reexamination of magnetostratigraphy and calcareous nannofossil biostratigraphy of this formation was carried out. The results show that the strata with stable remanent magnetizations have reversed magnetic polarities only, and the layers with marine sedimentary facies consistently contain specimens of large Gephyrocapsa. These updated results suggest that the Tananwan Formation was deposited within the interval of 1.46 - 1.24 Ma, corresponding to a short period of reversed magnetic polarity of the Matuyama Epoch.

  9. Observations and modelling of soil slip-debris flow initiation processes in pyroclastic deposits: the Sarno 1998 event

    OpenAIRE

    Crosta, G. B.; Negro, P.

    2003-01-01

    Pyroclastic soils mantling a wide area of the Campanian Apennines are subjected to recurrent instability phenomena. This study analyses the 5 and 6 May 1998 event which affected the Pizzo d’Alvano (Campania, southern Italy). More than 400 slides affecting shallow pyroclastic deposits were triggered by intense and prolonged but not extreme rainfall. Landslides affected the pyroclastic deposits that cover the steep calcareous ridges and are ...

  10. Responses of lucerne (Medicago sativa L.) and rhizobia to copper-based fungicide application in two contrasting soils

    Science.gov (United States)

    Schneider, Martin; Dober, Melanie; Jöchlinger, Lisa; Keiblinger, Katharina; Soja, Gerhard; Mentler, Axel; Zechmeister-Boltenstern, Sophie; Bruckner, Alexander; Golestani Fard, Alireza; Wenzel, Walter; Zehetner, Franz

    2016-04-01

    For more than 120 years, salts of copper (Cu) have been used in viticulture to prevent damages by fungal diseases. Due to restrictions in the use of synthetic fungicides and mineral fertilizers, organic viticulture depends on Cu as well as on biological nitrogen fixation. Here, we conducted an eco-toxicological pot experiment with an acidic, sandy soil and a calcareous, loamy soil and incrementally increasing fungicide application rates from 0 to 5000 mg Cu kg-1 soil. Lucerne (Medicago sativa L. cultivar. Plato) was grown in the pots for 3 months under greenhouse conditions. Acetylene reduction assays performed with harvested nodules showed no response to elevated soil Cu concentrations indicating that the nitrogen fixing capacity of rhizobia was not compromised by Cu in our experiment. Nevertheless, the nodule biomass was very sensitive to Cu and strongly decreased due to reduced amounts of fine roots and less energy supply by the plant. Legumes are known to be Cu-sensitive, and our contribution also showed a decrease in harvest by 50 % (EC50) at 21 mg kg-1 plant Cu tissue concentration in the acidic soil and at 30 mg kg-1 in the calcareous soil. This corresponded to diffusional fluxes measured by diffusive gradients in thin films (DGT) of 202 and 368 fmol cm-2 s-1, respectively. DGT measurements showed that in the acidic soil, Cu was 2 to 10 times more available for plants, depending on the concentration applied, than in the calcareous soil. A modeling approach for estimating the effective concentration (EC) by including the DGT-estimated plant Cu content and the pH produced more accurate values (NRMSE of 21.9 to 20.1 %) than EC directly estimated from DGT.

  11. 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

  12. Calcareous Bio-Concretions in the Northern Adriatic Sea: Habitat Types, Environmental Factors that Influence Habitat Distributions, and Predictive Modeling.

    Science.gov (United States)

    Falace, Annalisa; Kaleb, Sara; Curiel, Daniele; Miotti, Chiara; Galli, Giovanni; Querin, Stefano; Ballesteros, Enric; Solidoro, Cosimo; Bandelj, Vinko

    2015-01-01

    Habitat classifications provide guidelines for mapping and comparing marine resources across geographic regions. Calcareous bio-concretions and their associated biota have not been exhaustively categorized. Furthermore, for management and conservation purposes, species and habitat mapping is critical. Recently, several developments have occurred in the field of predictive habitat modeling, and multiple methods are available. In this study, we defined the habitats constituting northern Adriatic biogenic reefs and created a predictive habitat distribution model. We used an updated dataset of the epibenthic assemblages to define the habitats, which we verified using the fuzzy k-means (FKM) clustering method. Redundancy analysis was employed to model the relationships between the environmental descriptors and the FKM membership grades. Predictive modelling was carried out to map habitats across the basin. Habitat A (opportunistic macroalgae, encrusting Porifera, bioeroders) characterizes reefs closest to the coastline, which are affected by coastal currents and river inputs. Habitat B is distinguished by massive Porifera, erect Tunicata, and non-calcareous encrusting algae (Peyssonnelia spp.). Habitat C (non-articulated coralline, Polycitor adriaticus) is predicted in deeper areas. The onshore-offshore gradient explains the variability of the assemblages because of the influence of coastal freshwater, which is the main driver of nutrient dynamics. This model supports the interpretation of Habitat A and C as the extremes of a gradient that characterizes the epibenthic assemblages, while Habitat B demonstrates intermediate characteristics. Areas of transition are a natural feature of the marine environment and may include a mixture of habitats and species. The habitats proposed are easy to identify in the field, are related to different environmental features, and may be suitable for application in studies focused on other geographic areas. The habitat model outputs

  13. High-resolution calcareous nannoplankton palaeoecology as a proxy for small-scale environmental changes in the Early Miocene.

    Science.gov (United States)

    Auer, Gerald; Piller, Werner E; Harzhauser, Mathias

    2014-09-01

    Within a 5.5-m-thick succession of upper Burdigalian (CNP-zone NN4) shallow neritic sediments from the North Alpine Foreland Basin in Lower Austria a high-resolution section of finely laminated sediment with a thickness of 940.5 mm was logged. The section was continuously sampled, resulting in 100 samples, covering a thickness of ~ 10 mm each. An integrated approach was applied to these samples in order to study proxy records including calcareous nannoplankton, geochemical and geophysical data. Multivariate statistics on the autochthonous assemblage were used to evaluate the ecological preferences of each taxon and to rule out possible contamination of the signal by taphonomic processes. In order to assess changes in the assemblage composition throughout the section, three taphogroups were defined using both the autochthonous and allochthonous nannofossils. Based on the distribution of these taphogroups five distinct intervals were defined that are indicative of centennial to decadal changes in palaeoenvironmental conditions. Combining these results with other proxies (geochemistry, geophysics) we were able to reconstruct short-term, small-scale variations in terms of temperature, primary productivity, bottom water oxygenation, organic matter flux, freshwater influx and changes in relative sea level in a highly dynamic shallow marine setting. This study represents the first such high-resolution analysis performed on a marine succession of late Burdigalian age. It is also a first attempt to analyse outcrop data on such a high-resolution, sub-Milankovitch scale, with respect to calcareous nannoplankton in conjunction with geochemical and sedimentological data.

  14. Identification and pharmacological induction of autophagy in the larval stages of Echinococcus granulosus: an active catabolic process in calcareous corpuscles.

    Science.gov (United States)

    Loos, Julia A; Caparros, Pedro A; Nicolao, María Celeste; Denegri, Guillermo M; Cumino, Andrea C

    2014-06-01

    Autophagy is a fundamental catabolic pathway conserved from yeast to mammals, but which remains unknown in parasite cestodes. In this work, the pharmacological induction of autophagy was cellularly and molecularly analysed in the larval stages of Echinococcus granulosus. Metacestode sensitivity to rapamycin and TORC1 expression in protoscoleces and metacestodes were shown. Ultrastructural studies showed that treated parasites had an isolation membrane, autophagosomes and autolysosomes, all of which evidenced the autophagic flux. Genes coding for key autophagy-related proteins were also identified in the Echinococcus genome. These genes were involved in autophagosome formation and transcriptional over-expression of Eg-atg5, Eg-atg6, Eg-atg8, Eg-atg12, Eg-atg16 and Eg-atg18 was shown in presence of rapamycin or arsenic trioxide. Thus, Echinococcus autophagy could be regulated by non-transcriptional inhibition through TOR and by transcription-dependent up-regulation via FoxO-like transcription factors and/or TFEB proteins. An increase in the punctate pattern and Eg-Atg8 polypeptide level in the tegument, parenchyma cells and excretory system of protoscoleces and in vesicularised parasites was detected after rapamycin treatment. This suggests the occurrence of basal autophagy in the larval stages and during vesicular development. In arsenic-treated protoscoleces, high Eg-Atg8 polypeptide levels within the free cytoplasmic matrix of calcareous corpuscles were observed, thus verifying the occurrence of autophagic events. These experiments also confirmed that the calcareous corpuscles are sites of arsenic trioxide accumulation. The detection of the autophagic machinery in this parasite represents a basic starting point to unravel the role of autophagy under both physiological and stress conditions which will allow identification of new strategies for drug discovery against neglected parasitic diseases caused by cestodes.

  15. 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

  16. Calcareous Bio-Concretions in the Northern Adriatic Sea: Habitat Types, Environmental Factors that Influence Habitat Distributions, and Predictive Modeling.

    Directory of Open Access Journals (Sweden)

    Annalisa Falace

    Full Text Available Habitat classifications provide guidelines for mapping and comparing marine resources across geographic regions. Calcareous bio-concretions and their associated biota have not been exhaustively categorized. Furthermore, for management and conservation purposes, species and habitat mapping is critical. Recently, several developments have occurred in the field of predictive habitat modeling, and multiple methods are available. In this study, we defined the habitats constituting northern Adriatic biogenic reefs and created a predictive habitat distribution model. We used an updated dataset of the epibenthic assemblages to define the habitats, which we verified using the fuzzy k-means (FKM clustering method. Redundancy analysis was employed to model the relationships between the environmental descriptors and the FKM membership grades. Predictive modelling was carried out to map habitats across the basin. Habitat A (opportunistic macroalgae, encrusting Porifera, bioeroders characterizes reefs closest to the coastline, which are affected by coastal currents and river inputs. Habitat B is distinguished by massive Porifera, erect Tunicata, and non-calcareous encrusting algae (Peyssonnelia spp.. Habitat C (non-articulated coralline, Polycitor adriaticus is predicted in deeper areas. The onshore-offshore gradient explains the variability of the assemblages because of the influence of coastal freshwater, which is the main driver of nutrient dynamics. This model supports the interpretation of Habitat A and C as the extremes of a gradient that characterizes the epibenthic assemblages, while Habitat B demonstrates intermediate characteristics. Areas of transition are a natural feature of the marine environment and may include a mixture of habitats and species. The habitats proposed are easy to identify in the field, are related to different environmental features, and may be suitable for application in studies focused on other geographic areas. The habitat

  17. Soil erosion in Iran: Issues and solutions

    Science.gov (United States)

    Hamidreza Sadeghi, Seyed; Cerdà, Artemi

    2015-04-01

    Iran currently faces many soil erosion-related problems (see citations below). These issues are resulted from some inherent characteristic and anthropogenic triggering forces. Nowadays, the latter plays more important rule to accelerate the erosion with further emphasis on soil erosion-prone arid and semi arid regions of the country. This contribution attempts to identify and describe the existing main reasons behind accelerated soil erosion in Iran. Appropriate solutions viz. structural and non-structural approaches will be then advised to combat or minimise the problems. Iran can be used as a pilot research site to understand the soil erosion processes in semiarid, arid and mountainous terrain and our research will review the scientific literature and will give an insight of the soil erosion rates in the main factors of the soil erosion in Iran. Key words: Anthropogenic Erosion, Land Degradation; Sediment Management; Sediment Problems Acknowledgements The research projects GL2008-02879/BTE, LEDDRA 243857 and PREVENTING AND REMEDIATING DEGRADATION OF SOILS IN EUROPE THROUGH LAND CARE (RECARE)FP7-ENV-2013- supported this research. References Aghili Nategh, N., Hemmat, A., & Sadeghi, M. (2014). Assessing confined and semi-confined compression curves of highly calcareous remolded soil amended with farmyard manure. Journal of Terramechanics, 53, 75-82. Arekhi, S., Bolourani, A. D., Shabani, A., Fathizad, H., Ahamdy-Asbchin, S. 2012. Mapping Soil Erosion and Sediment Yield Susceptibility using RUSLE, Remote Sensing and GIS (Case study: Cham Gardalan Watershed, Iran). Advances in Environmental Biology, 6(1), 109-124. Arekhi, S., Shabani, A., Rostamizad, G. 2012. Application of the modified universal soil loss equation (MUSLE) in prediction of sediment yield (Case study: Kengir Watershed, Iran). Arabian Journal of Geosciences, 5(6), 1259-1267.Sadeghi, S. H., Moosavi, V., Karami, A., Behnia, N. 2012. Soil erosion assessment and prioritization of affecting factors at plot

  18. Evaluation of the assimilation of As by vegetables in contaminated soils submitted to a remediation process

    Science.gov (United States)

    Pérez-Sirvent, Carmen; Martinez Sanchez, Maria Jose; Agudo, Ines; Belen Martinez, Lucia; Bech, Jaume

    2016-04-01

    A greenhouse trial was carried out to evaluate the assimilation of heavy metals by three types of plants (lettuce, onion and broccoli), different parts of which are destined for human and farm animals consumption (leaves, roots, fruits). The experiments were carried out to check the validity of the use of calcareous materials to recover soils contaminated with heavy metals. The aim of this work was to apply a technology for decontamination to ensure that As do not enter into the trophic chain at risky levels and analyze and to assess the risk pre and post operational of the different treatments proposed. The materials used was a soils to be remediated (mining soils) and the materials used for remediation were lime filler and Construction and Demolition Waste (CDW). The plants were cultivated in greenhouse with several types of soil. Five experiments were used, namely, Tc (contaminated soil), T1 (uncontaminated soil (blank soil)), T2 (50% T1 + 50% Tc), T3 (Tc + (25%) lime residues coming from quarries) and T4 (Tc + (25%) residues coming from demolition and construction activities). The entire project involves twenty experiments which were prepared from soils highly contaminated mixed with two types of calcareous materials. The total As content of the soils samples, rhizosphere and vegetable samples, were measured and the translocation factor (TF), which is defined as the ratio of metal concentration in the leaves or shoots to the roots, and the Bioconcentration factor (BCF), which is defined as the ratio of metal concentration in the roots to that in soil were calculated. The use of CDR is shown to be a suitable way for remediating soils contaminated by metals. The methodology permits a revalorization of CDW.

  19. Interrelationships between soil cover and plant cover depending on land use

    Directory of Open Access Journals (Sweden)

    Tiina Köster

    2013-05-01

    Full Text Available Interrelationships between soil cover and plant cover of normally developed (or postlithogenic mineral soils are analysed on the basis of four sampling soil groups. The four-link pedo-ecological sequence of analysed soils, rendzinas → brown soils → pseudopodzolic soils → gley-podzols, forms a representative cross section in relation to the normal mineral soils of Estonia. All groups differ substantially from each other in terms of soil properties (calcareousness, acidity, nutrition conditions, profile fabric and humus cover. The primary tasks of the research were (1 to elucidate the main pedo-ecological characteristics of the four soil groups and their suitability for plant cover, (2 to evaluate comparatively soils in terms of productivity, sustainability, biodiversity and environmental protection ability and (3 to analyse possibilities for ecologically sound matching of soil cover with suitable plant cover. On the basis of the same material, the influence of land-use change on humus cover (epipedon fabric, properties of the entire soil cover and soil–plant interrelationship were also analysed. An ecosystem approach enables us to observe particularities caused by specific properties of a soil type (species, variety in biological turnover and in the formation of biodiversity.

  20. Changes of Organic Matter, N, P and K Content of Soils in Red Soil Areas Under Long-Term Experiment

    Institute of Scientific and Technical Information of China (English)

    JIANG Duan-sheng; ZENG Xi-bai; GAO Ju-sheng; LI Lian-fang

    2008-01-01

    The content of organic matter (OM), nitrogen (N), phosphorus (P), and potassium (K) in the three selected soils, including Calcaric Purpli-Orthic Primosols (purple sand-shale parent material), Dystric Turbi-Anthric Primosols (quaternary red clay parent material) and Typic Udi-Sandic Primosols (granite parent material) were studied under a long-term experiment by using crop straw and inorganic fertilizers at the Hunan Red Soil Experiment Station of Chinese Academy of Agricultural Sciences. The results showed that the contents of OM, N, P and K in the three selected soils increased after 23 years application of crop straw and inorganic fertilizers, but the contents increased much less when crop straw or inorganic fertilizers was applied alone. The nutrient contents in the three soils developed from granite changed more remarkably than those in the soil derived from quaternary red clay and purple sand-shale. It was also found that the contents of OM, N, and P increased slightly in the treatments without applying fertilizers or returning the crop straw to the root bed. Combined application of inorganic fertilizers and crop straw could remarkably increase the contents of OM, alkali- hydrolyzable N and available K, the positive correlation between application of organic fertilizers and increase of OM in soil did not always happened, it provided evidence for the relation between appropriate C/N ratio and accumulation of OM in soil. The increase of nutrient content was influenced by the soil properties. By comparing the contents of nutrient in 0-20 cm depth in the three different soils, it was concluded that the most increases of OM, alkali-hydrolyzable N, and available P were observed in Typic Udi-Sandic Primosols with the average increase by 3.03, 27.38, and 21.73 mg kg-1, respectively. The available K increased in Dystric Turbi-Anthric Primosols with the average increase by 25.82 mg kg-1, while it decreased in Calcaric Purpli-Orthic Primosols and Typic Udi

  1. On the term “calcar femorale” in Chinese%“股骨距”还是“股骨矩”?

    Institute of Scientific and Technical Information of China (English)

    梅炯

    2016-01-01

    The word “calcar femorale” is an old term in western medicine. In 1874, Von Fr. Merkel described the calcar femorale in German literature, as “der Schenkelsporn”, that is “femoral spur”. In 1942, Henry Morris referred to the calcar femorale as follows: “A nearly vertical plate of compact tissue, the calcar femorale projects into the neck of the bone from the inferior cervical region toward the greater trochanter”. This may be an earlier description of the term “calcar femorale”. In the case of the Chinese description of the term, Chinese surgeon, Dr. Zhang Jiayu, translated it into “股骨 ( femur )根 (gēn )” in 1952. And then, many professionals, including Prof. Guo Bangfu, Prof. Dai Kerong, et al. used “股骨距 ( jù )” in their papers. Ever since 1980s, the term “股骨矩 (jǔ )” began to appear in textbooks and some orthopedic journals, the two terms, “股骨矩” and “股骨距”, have appeared simultaneously for a long time. Which after all is, or, are both, right? The word “calcar”, the Latin term for “spur”, isdeifned as: “1. spur; 2. a spur-shaped structure” in many English dictionaries. In The Chinese Xinhua Dictionary, the word “距” has the meaning of calcar, but the word “矩” lacks such a deifnition. Therefore, the Chinese translation “距” is appropriate. So far as in the author’s view, the ifrst misuse of the Chinese character “矩” should have appeared in the surgery teaching material ( the 1st edition ) of the national universal textbook of surgery. Its text used the word “股骨矩”, and at the same time, in the relevant icon annotation and footnote explanation, the Chinese word “股骨距” appeared over 10 times. It is concluded that the “股骨矩” in the ifrst edition of textbook of Surgery probably was a printing error. This printing error has been widely accepted because of the authority of the textbook.

  2. 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

  3. Mineral materials as feasible amendments to stabilize heavy metals in polluted urban soils.

    Science.gov (United States)

    Zhang, Mingkui; Pu, Jincheng

    2011-01-01

    Four minerals, agricultural limestone (AL), rock phosphate (RP), palygorskite (PG), and calcium magnesium phosphate (CMP), were evaluated by means of chemical fractions of heavy metals in soils and concentrations of heavy metals in leachates from columns to determine their ability to stabilize heavy metals in polluted urban soils. Two urban soils (calcareous soil and acidic soil) polluted with cadmium, copper, zinc and lead were selected and amended in the laboratory with the mineral materials) for 12 months. Results indicated that application of the mineral materials reduced exchangeable metals in the sequence of Pb, Cd > Cu > Zn. The reduction of exchangeable fraction of heavy metals in the soils amended with different mineral materials followed the sequence of CMP, PG > AL > RP. Reductions of heavy metals leached were based on comparison with cumulative totals of heavy metals eluted through 12 pore volumes from an untreated soil. The reductions of the metals eluted from the calcareous soil amended with the RP, AL, PG and CMP were 1.98%, 38.89%, 64.81% and 75.93% for Cd, 8.51%, 40.42%, 60.64% and 55.32% for Cu, 1.76%, 52.94%, 70.00% and 74.12% for Pb, and 28.42%, 52.74%, 64.38% and 49.66% for Zn. Those from the acidic soil amended with the CMP, PG, AL, and RP were 25.65%, 68.06%, 78.01% and 79.06% for Cd, 26.56%, 49.64%, 43.40% and 34.68% for Cu, 44.44%, 33.32%, 61.11% and 69.44% for Pb, and 18.46%, 43.77%, 41.98% and 40.68% for Zn. The CMP and PG treatments were superior to the AL and RP for stabilizing heavy metals in the polluted urban soils.

  4. Discovery of laterally extensive drape of siliciclastic silt in the Northern Calcareous Alps, Austria: Late-glacial to ?early Holocene aeolian deposition.

    Science.gov (United States)

    Gild, Charlotte; Geitner, Clemens; Haas, Jean Nicolas; Sanders, Diethard

    2016-04-01

    Field surveys in the Northern Calcareous Alps (NCA, a nappe stack of Triassic carbonate rocks) revealed a drape, or drapes, typically 20-40 cm in thickness of siliciclastic silt over extensive landscape areas, from valley floors to LGM (Last Glacial Maximum) nunataks. The drape veneers substrates ranging from country rocks to diverse post-LGM deposits - the latter with depositional and/or erosional topographies. The drape mostly is overlain by vegetated organic material and, in turn, tops inactive/abandoned post-LGM successions of fluvial (including kame terrace), alluvial fan, scree slope, LGM basal till, and rock-avalanche origin. The drape extends over kilometers at least (limit of field investigation in specific areas), up to LGM nunatak plateaus. Deposystems (e.g., scree slopes, alluvial fans) on carbonate-rocky terrain that remained active until the Holocene are not topped by the drape; a level of siliciclastic silt, however, was spotted within a few of these successions. The possibility that several levels of silt are intercalated within or top post-glacial deposits cannot be excluded at present; the large lateral extent and the stratigraphic position, however, suggest that at least most locations pertain to a single widespread level (with that reservation, we prefer to speak in singular of the drape). Over the inspected area (~ 90 x 20 km), the drape consists mainly of silt-sized grains of quartz, feldspars, micas, and amphiboles; at a few sites, calci- or dolosilt are admixed. Most of the grains are angular to subrounded, some grains show features of corrosion. Preliminary palynological analyses of this silt - seven locations from LGM nunataks to kame terrace and alluvial fans - suggest vegetation types that, together, may be assigned to palaeoclimates ranging from the late-glacial (Younger Dryas?) to the middle Holocene. A few of the pollen spectra appear to record sparse vegetation cover allowing for enhanced aeolian deposition, but other spectra (e

  5. Soil Formation and Taxonomy in Yeşilırmak River Terraces

    Directory of Open Access Journals (Sweden)

    Alper Durak

    2014-02-01

    Full Text Available In this study, the soils of which parent material is alluvial and formed Yeşilırmak river terraces were investigated. For this purposes four different profiles were excavated in the study area. Then twenty-seven soil samples were taken from horizons of four profiles and their physical and chemical analyses were done for soil taxonomy research. Profile of Kumocagi and Cakil were classified in subgroup as Typic Ustipsamments, Havaalanı and Mera profiles were classified Typic Haplustolls and Typic Argiustolls subgroups respectively. The pH values of soils varied between 7.38-8.41. These soils can be classified as low and highly basic. Most of the soil series had an irregular pH distribution in the profile. The range of carbonate content of the soils was 0.8-25.4%. Although carbonate content of soils showed a very wide range, majority of them can be classified as highly calcareous. In most of soils carbonate content was distributed irregulary in the profile. Organic matter content were between 0.14-6.11% in the soils. Although organic matter contents of the soils changed in a wide range most of them had low organic matter content. Organic matter content was over 4% in the surface horizon of only two profiles. Research result showed that, alluvial parent material, particle size, topograpy and time have different effect on investigation soils.

  6. DESCRIPTION OF CERTAIN ASPECTS OF THE PRODUCTION POTENTIAL OF SOILS TAMAN PENINSULA

    Directory of Open Access Journals (Sweden)

    Lukyanov A. A.

    2015-10-01

    Full Text Available The work presents the results of the scientific research in the Taman Peninsula soil properties. We carry out the historic review of the studies in the Taman Peninsula soils, and its geological structure. We present morphological characteristics of the soil profile for the southern, calcareous, ultra heavy loam chernozem developed from the loessial loams and forming genetic horizons. The studies of the humus content in the soils show the associations between its percentage and the type and intensity of the agricultural use. Studies of the soils structure and composition demonstrate marked aggravation of the soils physical properties caused by grape growing. The best results of the particle size analysis have been achieved for the woodland soils. In woodlands, after their establishment, the soils under the grass and crown layers develop free of the anthropogenic impact. We register self-supporting growth of organic matter and natural processes of soil fertility recovery; therefore, such soils are characterized with a greater content of organic matter as compared to the soils under grape plantings cultivated in the monoculture regime. Reduced soil organic matter (humus content in vineyards results from the disturbed biological interchange of the matter and increased anthropogenic impact causing erosion processes

  7. Ammonium citrate as enhancement for electrodialytic soil remediation and investigation of soil solution during the process

    DEFF Research Database (Denmark)

    Dias-Ferreira, Celia; Kirkelund, Gunvor Marie; Ottosen, Lisbeth M.

    2015-01-01

    Seven electrodialytic experiments were conducted using ammonium citrate as enhancing agent to remediate copper and chromium-contaminated soil from a wood-preservation site. The purpose was to investigate the effect of current density (0.2, 1.0 and 1.5 mA cm−2), concentration of enhancing agent (0...... to remediate metal polluted soils at neutral to alkaline pH by choosing a good enhancement solution.......Seven electrodialytic experiments were conducted using ammonium citrate as enhancing agent to remediate copper and chromium-contaminated soil from a wood-preservation site. The purpose was to investigate the effect of current density (0.2, 1.0 and 1.5 mA cm−2), concentration of enhancing agent (0.......25, 0.5 and 1.0 M) and remediation times (21, 42 and 117 d) for the removal of Cu and Cr from a calcareous soil. To gain insight on metal behavior, soil solution was periodically collected using suction cups. It was seen that current densities higher than 1.0 mA cm−2 did not increase removal and thus...

  8. Effects of liming on soil properties and plant performance of temperate mountainous grasslands.

    Science.gov (United States)

    Mijangos, Iker; Albizu, Isabel; Epelde, Lur; Amezaga, Ibone; Mendarte, Sorkunde; Garbisu, Carlos

    2010-10-01

    The application of lime or liming materials to acid-soil grasslands might help mitigate soil acidity, a major constraint to forage productivity in many temperate mountainous grasslands. Nowadays, in these mountainous grasslands, it is essential to promote agricultural practices to increase forage yield and nutritive value while preserving biodiversity and agroecosystem functioning. Two different field experiments were conducted in the Gorbeia Natural Park, northern Spain: (i) one in a calcareous mountainous grassland (Arraba) and (ii) the other in a siliceous mountainous grassland (Kurtzegan) to study the effects of a single application of two liming products, i.e. 2429 kg lime (164.3% CaCO(3)) ha(-1) and 4734 kg calcareous sand (84.3% CaCO(3)) ha(-1), applied one month before the beginning of the sheep grazing season (May-October), on soil chemical (pH, organic C, total N, C/N ratio, %Al saturation, Olsen P, exchangeable K(+) and Ca(2+)) and biological parameters (dehydrogenase, beta-glucosidase, urease, acid phosphatase and arylsulphatase activity) as well as on botanical diversity (graminoids, forbs, shrubs) and forage yield and nutritive value (crude protein, modified acid detergent fibre, digestibility). Untreated control plots were also included in the experiment. Soil sampling was carried out at the end of the sheep grazing season (6 months after liming treatment), while botanical composition was determined one year after treatments application. Although no increase in soil pH was observed in Arraba, liming significantly increased dehydrogenase activity (an indicator of soil microbial activity) by 30.4 and 86.7% at Arraba and Kurtzegan site, respectively. Liming treatments significantly improved forage yield and nutritive value in Arraba but not in Kurtzegan. Furthermore, no differences in soil biological quality, evaluated using the "treated-soil quality index" as proposed in this work, were observed between treated and untreated soils, and between the two

  9. Occurrence of the freshwater jellyfish Craspedacusta sowerbii (Lankester, 1880) (Hydrozoa, Limnomedusae) in a calcareous lake in Mato Grosso do Sul, Brazil

    OpenAIRE

    Silva,William Marcos; Roche, Kennedy Francis

    2007-01-01

    The occurrence of the freshwater jellyfish Craspedacusta sowerbii (=sowerbyi) Lankester, 1880 was recorded in April 2006 in the Lagoa Misteriosa water body, a calcareous lake (doline) in Mato Grosso do Sul State, Brazil. Only Rotifera composed the zooplankton community was composed only of Rotifera and the environment was meso-eutrophic system. The nomenclature of C. sowerbii is discussed with regard to the use of the correct spelling and an alternative one. The distributions of C. sowerbii i...

  10. A new hypogean Trechus Clairville (Coleoptera, Carabidae, Trechini) discovered in a non-calcareous Superficial Subterranean Habitat of the Iberian System (Central Spain).

    Science.gov (United States)

    Ortuño, Vicente M; Cuesta, Eva; Gilgado, José D; Ledesma, Enrique

    2014-01-01

    A new hypogean species of Trechus Clairville, Trechus arrecheai sp. nov., is described from the Iberian Peninsula. It was captured by subterranean pitfall traps in a non-calcareous Superficial Subterranean Habitat from the Moncayo Massif (Zaragoza, Spain). Data on the accompanying fauna are provided and the biogeographical implications of this discovery are discussed. A synthesis of the data about the known distribution of the Trechus angusticollis species group is provided.

  11. Effects of drought on leaf carbon source and growth of European beech are modulated by soil type

    Science.gov (United States)

    Liu, Jian-Feng; Arend, Matthias; Yang, Wen-Juan; Schaub, Marcus; Ni, Yan-Yan; Gessler, Arthur; Jiang, Ze-Ping; Rigling, Andreas; Li, Mai-He

    2017-02-01

    Drought potentially affects carbon balance and growth of trees, but little is known to what extent soil plays a role in the trade-off between carbon gain and growth investment. In the present study, we analyzed leaf non-structural carbohydrates (NSC) as an indicator of the balance of photosynthetic carbon gain and carbon use, as well as growth of European beech (Fagus sylvatica L.) saplings, which were grown on two different soil types (calcareous and acidic) in model ecosystems and subjected to a severe summer drought. Our results showed that drought led in general to increased total NSC concentrations and to decreased growth rate, and drought reduced shoot and stem growth of plants in acidic soil rather than in calcareous soil. This result indicated that soil type modulated the carbon trade-off between net leaf carbon gain and carbon investment to growth. In drought-stressed trees, leaf starch concentration and growth correlated negatively whereas soluble sugar:starch ratio and growth correlated positively, which may contribute to a better understanding of growth regulation under drought conditions. Our results emphasize the role of soil in determining the trade-off between the balance of carbon gain and carbon use on the leaf level and growth under stress (e.g. drought).

  12. Accumulation of mercury in rice grain and cabbage grown on representative Chinese soils

    Institute of Scientific and Technical Information of China (English)

    Chun-fa LIU; Ting-qiang LI; Xiao-e YANG; Cheng-xian WU; Muhammad T. RAFIQ; Rukhsanda AZIZ; Dan-di HOU; Zhe-li DING; Zi-wen LIN; Lin-jun LOU; Yuan-yuan FENG

    2013-01-01

    A pot culture experiment was carried out to investigate the accumulation properties of mercury (Hg) in rice grain and cabbage grown in seven soil types (Udic Ferrisols, Mol isol, Periudic Argosols, Latosol, Ustic Cambosols, Calcaric Regosols, and Stagnic Anthrosols) spiked with different concentrations of Hg (CK, 0.25, 0.50, 1.00, 2.00, and 4.00 mg/kg). The results of this study showed that Hg accumulation of plants was significantly affected by soil types. Hg concentration in both rice grain and cabbage increased with soil Hg concentrations, but this increase differed among the seven soils. The stepwise multiple regression analysis showed that pH, Mn(II), particle size distribution, and cation exchange capacity have a close relationship with Hg accumulation in plants, which suggested that physico-chemical characteristics of soils can affect the Hg accumulation in rice grain and cabbage. Critical Hg concentrations in seven soils were identified for rice grain and cabbage based on the maximum safe level for daily intake of Hg, dietary habits of the population, and Hg accumulation in plants grown in different soil types. Soil Hg limits for rice grain in Udic Ferrisols, Mol isol, Periudic Argosols, Latosol, Ustic Cambosols, Calcaric Regosols, and Stagnic Anthrosols were 1.10, 2.00, 2.60, 2.78, 1.53, 0.63, and 2.17 mg/kg, respectively, and critical soil Hg levels for cabbage are 0.27, 1.35, 1.80, 1.70, 0.69, 1.68, and 2.60 mg/kg, respectively.

  13. Accumulation of mercury in rice grain and cabbage grown on representative Chinese soils.

    Science.gov (United States)

    Liu, Chun-fa; Wu, Cheng-xian; Rafiq, Muhammad T; Aziz, Rukhsanda; Hou, Dan-di; Ding, Zhe-li; Lin, Zi-wen; Lou, Lin-jun; Feng, Yuan-yuan; Li, Ting-qiang; Yang, Xiao-e

    2013-12-01

    A pot culture experiment was carried out to investigate the accumulation properties of mercury (Hg) in rice grain and cabbage grown in seven soil types (Udic Ferrisols, Mollisol, Periudic Argosols, Latosol, Ustic Cambosols, Calcaric Regosols, and Stagnic Anthrosols) spiked with different concentrations of Hg (CK, 0.25, 0.50, 1.00, 2.00, and 4.00 mg/kg). The results of this study showed that Hg accumulation of plants was significantly affected by soil types. Hg concentration in both rice grain and cabbage increased with soil Hg concentrations, but this increase differed among the seven soils. The stepwise multiple regression analysis showed that pH, Mn(II), particle size distribution, and cation exchange capacity have a close relationship with Hg accumulation in plants, which suggested that physicochemical characteristics of soils can affect the Hg accumulation in rice grain and cabbage. Critical Hg concentrations in seven soils were identified for rice grain and cabbage based on the maximum safe level for daily intake of Hg, dietary habits of the population, and Hg accumulation in plants grown in different soil types. Soil Hg limits for rice grain in Udic Ferrisols, Mollisol, Periudic Argosols, Latosol, Ustic Cambosols, Calcaric Regosols, and Stagnic Anthrosols were 1.10, 2.00, 2.60, 2.78, 1.53, 0.63, and 2.17 mg/kg, respectively, and critical soil Hg levels for cabbage are 0.27, 1.35, 1.80, 1.70, 0.69, 1.68, and 2.60 mg/kg, respectively.

  14. Agronomic application of olive mill wastewater: Effects on maize production and soil properties.

    Science.gov (United States)

    Belaqziz, Majdouline; El-Abbassi, Abdelilah; Lakhal, El Khadir; Agrafioti, Evita; Galanakis, Charis M

    2016-04-15

    This study investigates the effect of direct amendment of olive mill wastewater (OMW) on the fertility of soil, described as poor in the area of Marrakech (semi-arid region) in Morocco. The treated plots were amended with untreated OMW generated by a traditional extraction process at the amount of 10 L/m(2)/year during two consecutive years. Results of these two years treatments with crude OMW at relatively high dose reveal an important increase in soil physicochemical characteristics, namely electric conductivity (EC), Na(+,) K(+), phosphorus, nitrogen, organic matter and soluble phenolic compounds. EC of treated soil was enhanced from 0.34 to 2.91 mS/cm as compared to the control soil. After spreading OMW in soil, the amounts of its nutritive elements increased by 81% for nitrogen, 66% for phosphorus and 88% for potassium. The accumulation of phenolic compounds and the increase of total peroxidase activity in plants provide evidence of their protective role against the physiological stress induced by OMW. However, this enrichment in mineral and nutritive elements decreased three months after OMW application, revealing OMW biodegradation in the studied calcareous soil. In parallel, an increase in the contents of the soluble phenolic compounds on the upper layer of soil was denoted and maize plants growth was efficiently raised. Significant amelioration was obtained notably in terms of fresh and dry weight of leaves, leaves area, spikes fresh and dry weight, 100 seeds weight and straw yield (37, 54, 27, 24, 14 and 9% respectively). Along with the correct choice of convenient soils notably calcareous ones and tolerant crops such as maize, this method could constitute an efficient approach for avoiding problems attributed to the uncontrolled disposal of these effluents and an effective strategy to regenerate degraded soils and represents an economical alternative that provides a local fertilizer.

  15. Vegetation-induced spatial variability of soil redox properties in wetlands

    Science.gov (United States)

    Szalai, Zoltán; Jakab, Gergely; Kiss, Klaudia; Ringer, Marianna; Balázs, Réka; Zacháry, Dóra; Horváth Szabó, Kata; Perényi, Katalin

    2016-04-01

    Vegetation induced land patches may result spatial pattern of on soil Eh and pH. These spatial pattern are mainly emerged by differences of aeration and exudation of assimilates. Present paper focuses on vertical extent and temporal dynamics of these patterns in wetlands. Two study sites were selected: 1. a plain wetland on calcareous sandy parent material (Ceglédbercel, Danube-Tisza Interfluve, Hungary); 2. headwater wetland with calcareous loamy parent material (Bátaapáti, Hungary). Two vegetation patches were studied in site 1: sedgy (dominated by Carex riparia) and reedy (dominated by Phragmites australis). Three patches were studied in site2: sedgy1 (dominated by C vulpina), sedgy 2 (C. riparia); nettle-horsetail (Urtica dioica and Equisetum arvense). Boundaries between patches were studied separately. Soil redox, pH and temperature studied by automated remote controlled instruments. Three digital sensors (Ponsell) were installed in each locations: 20cm and 40cm sensors represent the solum and 100 cm sensor monitors the subsoil). Groundwater wells were installed near to triplets for soil water sampling. Soil Eh, pH and temperature values were recorded in each 10 minutes. Soil water sampling for iron and DOC were carried out during saturated periods. Spatial pattern of soil Eh is clearly caused by vegetation. We measured significant differences between Eh values of the studied patches in the solum. We did not find this kinds horizontal differences in the subsoil. Boundaries of the patches usually had more reductive soil environment than the core areas. We have found temporal dynamics of the spatial redox pattern. Differences were not so well expressed during wintertime. These spatial patterns had influence on the DOC and iron content of porewater, as well. Highest temporal dynamics of soil redox properties and porewater iron could be found in the boundaries. These observations refer to importance patchiness of vegetation on soil chemical properties in

  16. Environmental perturbations at the early Eocene ETM2, H2, and I1 events as inferred by Tethyan calcareous plankton (Terche section, northeastern Italy)

    Science.gov (United States)

    D'Onofrio, Roberta; Luciani, Valeria; Fornaciari, Eliana; Giusberti, Luca; Boscolo Galazzo, Flavia; Dallanave, Edoardo; Westerhold, Thomas; Sprovieri, Mario; Telch, Sonia

    2016-09-01

    Several early Eocene hyperthermals have been recently investigated and characterized in terms of temperature anomalies and oceanographic changes. The effects of these climatic perturbations on biotic communities are much less constrained. Here we present new records from the Terche section (northeastern Italy) that, for the first time, integrates data on planktic foraminifera and calcareous nannofossils across three post-Paleocene-Eocene Thermal Maximum negative carbon isotope excursions (CIEs). The biomagnetostratigraphic framework generated at Terche allows us to confidently relate such CIEs to the Eocene Thermal Maximum 2 (ETM2), H2, and I1 events. Each of these events coincides with lithological anomalies characterized by significantly lower calcium carbonate content (marly units, MUs). We interpret these MUs as mainly linked to an effect of increased terrigenous dilution, as dissolution proxies do not display significant variations. Calcareous plankton assemblages change significantly across these events and radiolarians increase. Observed changes suggest that transient warming and environmental perturbations, though more intense during ETM2, occurred during each of the three investigated perturbations. Variations among calcareous plankton suggest increase in surface-water eutrophication with respect to the pre-event conditions, coupled with a weakening of the upper water-column thermal stratification. Higher nutrient discharge was related to intensification of the hydrological cycle as a consequence of the warmer climate. These conditions persisted during the early CIE recovery, implying slower recovery rates for the environment and biota than for the carbon cycle.

  17. Laboratory studies on the consolidation and protection of calcareous materials in the Cathedral of Oviedo. Part I

    Directory of Open Access Journals (Sweden)

    Grossi, Carlota

    1987-06-01

    Full Text Available The suitability of some consolidating and protecting products, to be applied to the deteriorated calcareous stones of the Cathedral of Oviedo, is presented. A proposed procedure and methodology for evaluating that suitability is also described. The studied stones, limestones and dolomites, have been experimentally subjected in laboratory to some treatment products: ethyl silicate, oligomeric silane and silicon resin. Some physical properties of those stones were evaluated before and after the treatments with the mentioned products. Those properties (porosity, water absorption, compressive strength and deformability, mechanical microfissuration threshold, acoustic emission, etc. were selected according to the significative role they play on the process of stone alteration or in supporting the proposed conclusions.

    Se presenta una metodología de trabajo encaminada a evaluar la idoneidad de ciertos productos consolidantes y protectores aplicados a piedras monumentales deterioradas. Para ello, en esta 1.ª parte, se determinan una serie de propiedades físicas, antes y después de aplicar los tratamientos. Dichas propiedades han sido seleccionadas por su incidencia en los mecanismos de alteración. Las piedras ensayadas proceden de la Catedral de Oviedo, son rocas calcáreas: calizas y dolomías. Los productos de tratamiento empleados han sido: silicato de etilo, silano oligomérico y resina silicónica. Se concluye con la comparación de las variaciones en las propiedades determinadas, antes y después del tratamiento, según el producto empleado.

  18. AUthigenic feldspar as an indicator of paleo-rock/water interactions in Permian carbonates of the Northern Calcareous Alps, Austria

    Science.gov (United States)

    Spotl, C.; Kralik, M.; Kunk, M.J.

    1996-01-01

    Dolostones interbedded with Upper Permian evaporites at the base of the Northern Calcareous Alps contain abundant authigenic K-feldspar. Two petrographically, structurally, and isotopically distinct generations of K-feldspar can be distinguished: crystals composed of an inclusion-rich core and a clear rim, and optically unzoned, transparent crystals. Both feldspar types have essentially identical K-feldspar end-member compositions with ??? 99.5 mole % Or component. Low oxygen isotope ratios (+16.1??? to +18.1??? SMOW) suggest precipitation from 18O-enriched, saline fluids at temperatures in excess of ??? 140??C. 40Ar/39Ar plateau-age spectra of five samples range from 145 ?? 1 to 144 ?? 1 Ma (Early Berriasian) and suggest that both types of feldspar were formed within an interval that did not exceed ??? 2 m.y. Rb/Sr model ages range from 152 to 140 Ma, assuming that the burial diagenetic regime was buffered with respect to strontium by the associated marine Permian evaporites. Authigenic K-feldspar records two distinct events of hot brine flow, most likely triggered by tectonic movements (detachment) and by an increase in the subsurface temperature in response to thrust loading.

  19. Last occurrence of Abathomphalus mayaroensis (Bolli foraminiferid index of the Cretaceous–Paleogene boundary: the calcareous nannofossil proof

    Directory of Open Access Journals (Sweden)

    Kędzierski Mariusz

    2015-06-01

    Full Text Available In the Gaj section (Polish Carpathians, Skole Nappe, Ropianka Formation, the Late Maastrichtian calcareous nannofossil biostratigraphy is compared with foraminiferal zonation based on the occurrence of the planktonic foraminiferid index species Abathomphalus mayaroensis. It appears that the LO of A. mayaroensis, which has been used previously in the studied section as the possible K/Pg boundary indicator is located below the boundary. The disappearance of A. mayaroensis along with other planktonic foraminiferids before the Cretaceous–Paleogene (K/Pg boundary mass extinction event may be a consequence of the Late Maastrichtian rapid warming pulses. Moreover, the Paleogene age cannot be supported by the FO of the benthic foraminiferid Rzehakina fissistomata, because it first appears together with the nannofossil Ceratolithoides kamptneri (zonal marker for the latest Maastrichtian UC20cTP Zone. According to the present study, the whole studied section represents the lower Upper to the upper Upper Maastrichtian UC20bTP and UC20cTP nannofossil zones, so that it corresponds to the lower-middle part of the planktonic foraminiferal A. mayaroensis Zone, which, according to the scheme by Caron (1985, should extend up to the K/Pg boundary.

  20. Biostratigrafia a foraminiferi del Cretaceo Superiore della successione di Parco Priore (Calcare di Altamura, Piattaforma Apula, Italia Meridionale

    Directory of Open Access Journals (Sweden)

    Luigi Spalluto

    2008-03-01

    Full Text Available This study focuses on the biostratigraphic analysis of an Upper Cretaceous 57 m-thick stratigraphicsedimentary succession outcropping in a quarry at Parco Priore, near the city of Altamura in theMurge (Southern Italy.In the studied area the Upper Cretaceous shallow water carbonate successions represent restrictedfacies deposited in inner shelf settings within the Apulian Platform (sensu D’Argenio, 1974. Duringthe Mesozoic, the Apulian Platform was one of the peri-adriatic platforms (D’Argenio, 1974 localizedalong the southern margin of the Tethys. These platforms have been often compared to the presentdayBahamas islands for their general shape, size, subsidence rates as well as their inner platformarchitecture (Bernoulli, 2001.The studied sedimentary succession, belonging to the Calcare di Altamura formation, is mainlycharacterised by bedded white-reddish bioclastic, often re-crystallised or dolomitised, mudstones/wackestones. White-grey calcarenitic and calcisiltitic bedded limestones and thin bedded palaeosoillevels are also present. The micropalaeontological assemblage is dominated by benthic foraminifers(Accordiella conica, Cuneolina pavonia, Moncharmontia apenninica, Minouxia conica, Rotorbinellascarsellai, Dicyclina schlumbergeri, Murgeina apula, Cuneolina spp., Pseudolituonella sp.,Aeolisaccus kotori, miliolids, textularids and dasycladacean algae (mainly Thaumatoporellaparvovesiculifera.This benthic association allows to refer the Parco Priore succession to the Coniacian‒lowerCampanian time interval. Sedimentological, lithological and micropalaeontological characteristicsof the studied succession point to a low-energy inner carbonate platform setting with occasional subaerialexposures.

  1. Effects on soil organic matter mineralization and microbiological properties of applying compost to burned and unburned soils.

    Science.gov (United States)

    Turrión, M B; Lafuente, F; Mulas, R; López, O; Ruipérez, C; Pando, V

    2012-03-01

    This study was undertaken in the context of a project of reclamation of a burned forest area applying municipal waste compost (MWC) and it consisted of an incubation experience carried out under laboratory conditions. The objectives of this research were to asses the effect of three doses of MWC added to burned and unburned calcareous soils on a) SOM mineralization and b) soil microbiological parameters. The laboratory incubation experience was carried out with three compost doses (1, 2 and 4% w/w) on a burned soil and another unburned one from an adjacent plot, besides the corresponding control samples. The mineralization kinetics of the organic matter was studied for 92 days. The kinetics data were adjusted to a double exponential model, showing two C pools of different degrees of resistance to mineralization and concentration, with half-life times of 1.9-4.9 and 34-76 days, respectively. In the unburned soil, the initial potential mineralization rate of the labile and stable C pools showed an opposed behavior, increased and decreased with the MWC dose, respectively. However in the burned soil no significant tendencies were observed. Although applying compost tended to increase the size of more labile pool with respect to total mineralizable C, however most of the soil or compost OM did not result mineralizable in the short and medium term. The compost amendment did not increase soil microbial activity.

  2. Biogeochemistry of plant-soil system in a limestone area: A case study of Mt. Kinsho-zan, Gifu prefecture, central Japan

    Science.gov (United States)

    Ueno, S.; Sugitani, K.; Ono, M.

    2010-12-01

    Limestone contains few of the nutrients essential for plant growth, such as Si, K, and P. Owing to its high concentrations of alkali earth elements and the resulting high pH, P and Fe tend to be sparingly available for plants in soils developed in limestone areas. Because of this limited availability of nutrients in calcareous soils, certain typical calcareous plants are known to occasionally dominate. On Mt. Kinsho-zan, a limestone mountain in Gifu prefecture, central Japan, however, typical calcareous plants are not seen; various non-calcareous plants appear and do not seem to be malnourished. In addition to the nutrients supplied by precipitation and eolian dusts, litter decomposition may supply nutrients, which could circulate in the plant-soil system. In this study, the soil properties (water content, loss on ignition, and pH) and the chemical compositions of soils, plant leaves (Chamaecyparis obtusa), and parental rocks (limestone) were analyzed to clarify the biogeochemical cycle of the plant-soil system on Mt. Kinsho-zan. A mountain composed of sandstone and mudstone, which lies near the main research area, was chosen for comparison. Chemical compositions were analyzed using an X-ray fluorescence spectrometer (Spectris Co., Ltd Panalytical Division Axios-N system). Ten major elements were analyzed in all samples, and 13 and 4 trace elements were analyzed for soils and plants and for limestones, respectively. In the limestone samples, the concentrations were as follows: SiO2 = 0.12-0.22wt%, Al2O3 = 0.054-0.13wt%, Fe2O3 = 0.021-0.057wt%, CaO = 55.12-55.33wt%, K2O = 40-55 ppm, TiO2 = 29-48 ppm, and Zr = 12-14 ppm. In soils developed in the limestone area, SiO2 = 43.48-55.46wt%, Al2O3 = 25.47-34.92wt%, Fe2O3 = 10.75-13.64wt%, CaO = 0.46-5.61wt%, K2O = 1.30-1.72wt%, TiO2 = 1.02-1.36wt%, and Zr = 240-319 ppm. Concentrations of Fe2O3, MnO, and P2O5 in soils from the limestone area are two times higher than those in soils from the sandstone-mudstone area; the

  3. Soils - NRCS Web Soil Survey

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — Web Soil Survey (WSS) provides soil data and information produced by the National Cooperative Soil Survey. It is operated by the USDA Natural Resources Conservation...

  4. From the study of fire effects on individual soil properties to the development of soil quality indices. 1. The pioneer research

    Science.gov (United States)

    Mataix-Solera, Jorge; Zornoza, Raúl

    2013-04-01

    water repellency induced by fire in calcareous Mediterranean forest soils. Eur. J. Soil Sci. 58, 1254-1259. Arcenegui, V., Mataix-Solera, J., Guerrero, C., Zornoza, R., Mataix-Beneyto, J., García-Orenes, F., 2008. Immediate effects of wildfires on water repellency and aggregate stability in Mediterranean calcareous soils. Catena 74, 219-226. Mataix-Solera, J., Doerr, S.H., 2004. Hydrophobicity and aggregate stability in calcareous topsoil from fire affected pine forests in southeastern Spain. Geoderma 118, 77-88. Mataix-Solera, J., Arcenegui, V., Guerrero, C., Jordán, M., Dlapa, P., Tessler, N., Wittenberg, L. 2008. Can terra rossa become water repellent by burning? A laboratory approach. Geoderma, 147, 178-184. Mataix-Solera, J., Cerdà, A., Arcenegui, V., Jordán, A., Zavala, L.M., 2011. Fire effects on soil aggregation: a review. Earth-Science Reviews 109, 44-60 Zornoza, R., Mataix-Solera, J., Guerrero, C., Arcenegui, V., Mayoral, A.M., Morales, J. Mataix-Beneyto, J., 2007b. Soil properties under natural forest in the Alicante Province of Spain. Geoderma. 142, 334-341. Zornoza, R., Mataix-Solera, J., Guerrero, C., Arcenegui, V., Mataix-Beneyto, J., Gómez, I., 2008. Validating the effectiveness and sensitivity of two soil quality indices based on natural forest soils under Mediterranean conditions. Soil Biology & Biochemistry. 40, 2079-2087.

  5. Reduction of soil pollution by usingwaste of the limestone in the cement industry

    Science.gov (United States)

    Muñoz, M. Cecilia Soto; Robles Castillo, Marcelo; Blanco Fernandez, David; Diaz Gonzalez, Marcos; Naranjo Lamilla, Pedro; Moore Undurraga, Fernando; Pardo Fabregat, Francisco; Vidal, Manuel Miguel Jordan; Bech, Jaume; Roca, Nuria

    2016-04-01

    In the cement manufacturing process (wet) a residue is generated in the flotation process. This builds up causing contamination of soil, groundwater and agricultural land unusable type. In this study to reduce soil and water pollution 10% of the dose of cement was replaced by waste of origin limestone. Concretes were produced with 3 doses of cement and mechanical strengths of each type of concrete to 7, 28 and 90 days were determined. the results indicate that the characteristics of calcareous residue can replace up to 10% of the dose of cement without significant decreases in strength occurs. It is noted that use of the residue reduces the initial resistance, so that the dose of cement should not be less than 200 kg of cement per m3. The results allow recommends the use of limestone waste since it has been observed decrease in soil and water contamination without prejudice construction material Keywords: Soil contamination; Limestone residue; Adding concrete

  6. Micronutrients in Soils, Crops, and Livestock

    Science.gov (United States)

    Gupta, Umesh C.; Wu, Kening; Liang, Siyuan

    Micronutrient concentrations are generally higher in the surface soil and decrease with soil depth. In spite of the high concentration of most micronutrients in soils, only a small fraction is available to plants. Micronutrients, also known as trace elements, are required in microquantities but their lack can cause serious crop production and animal health problems. Crops vary considerably in their response to various micronutrients. Brassicas and legumes are highly responsive to molybdenum (Mo) and boron (B), whereas corn and other cereals are more responsive to zinc (Zn) and copper (Cu). Micronutrient deficiencies are more common in humid temperate regions, as well as in humid tropical regions, because of intense leaching associated with high precipitation. Soil pH is one of the most important factors affecting the availability of micronutrients to plants. With increasing pH, the availability of these nutrients is reduced with the exception of Mo whose availability increases as soil pH increases. In most plant species, leaves contain higher amounts of nutrients than other plant parts. Therefore, whenever possible, leaves should be sampled to characterize the micronutrient status of crops. Deficiency symptoms for most micronutrients appear on the younger leaves at the top of the plant, whereas toxicity symptoms generally appear on the older leaves of plants. As summarized by Deckers and Steinnes, micronutrient deficiencies are widespread in developing countries, which have much poorer soil resources than the fertile soils of Europe and North America. Many of these areas lie in the humid tropics with extremely infertile, highly weathered, and/or highly leached soils, which are intensely deficient in nutrients. The rest of such soils are in the semiarid and areas adjacent to the latter, where alkaline and calcareous soil conditions severely limit the availability of micronutrients to plants. Frequently, the Cu, iron (Fe), manganese (Mn), Zn, and selenium (Se) levels

  7. Climate change impairs processes of soil and plant N cycling in European beech forests on marginal soil

    Science.gov (United States)

    Tejedor, Javier; Gasche, Rainer; Gschwendtner, Silvia; Leberecht, Martin; Bimüller, Carolin; Kögel-Knabner, Ingrid; Pole, Andrea; Schloter, Michael; Rennenberg, Heinz; Simon, Judy; Hanewinkel, Marc; Baltensweiler, Andri; Bilela, Silvija; Dannenmann, Michael

    2014-05-01

    Beech forests of Central Europe are covering large areas with marginal calcareous soils, but provide important ecological services and represent a significant economical value. The vulnerability of these ecosystems to projected climate conditions (higher temperatures, increase of extreme drought and precipitation events) is currently unclear. Here we present comprehensive data on the influence of climate change conditions on ecosystem performance, considering soil nitrogen biogeochemistry, soil microbiology, mycorrhiza ecology and plant physiology. We simultaneously quantified major plant and soil gross N turnover processes by homogenous triple 15N isotope labeling of intact beech natural regeneration-soil-microbe systems. This isotope approach was combined with a space for time climate change experiment, i.e. we transferred intact beech seedling-soil-microbe mesocosms from a slope with N-exposure (representing present day climate conditions) to a slope with S exposure (serving as a warmer and drier model climate for future conditions). Transfers within N slope served as controls. After an equilibration period of 1 year, three isotope labeling/harvest cycles were performed. Reduced soil water content resulted in a persistent decline of ammonia oxidizing bacteria in soil (AOB). Consequently, we found a massive five-fold reduction of gross nitrification in the climate change treatment and a subsequent strong decline in soil nitrate concentrations as well as nitrate uptake by microorganisms and beech. Because nitrate was the major nutrient for beech in this forest type with little importance of ammonium and amino acids, this resulted in a strongly reduced performance of beech natural regeneration with reduced N content, N metabolite concentrations and plant biomass. These findings provided an explanation for a large-scale decline of distribution of beech forests on calcareous soils in Europe by almost 80% until 2080 predicted by statistical modeling. Hence, we

  8. 钙质砂颗粒内孔隙的结构特征分析%Microscopic characterization of intra-pore structures of calcareous sands

    Institute of Scientific and Technical Information of China (English)

    朱长歧; 陈海洋; 孟庆山; 汪稔

    2014-01-01

    钙质砂是一种碳酸钙含量达50%以上的海洋生物成因的颗粒状材料。从微观结构上来看,钙质砂颗粒棱角度高、形状不规则、强度低、易破碎,且颗粒含有内孔隙。内孔隙的存在深刻影响着钙质砂的压缩、剪切和破碎等力学性能。利用激光技术对南沙群岛永暑礁环礁泻湖的未胶结钙质砂颗粒进行飞秒切割,通过光学显微镜探查并获取了颗粒的内孔隙图像,借助MATLAB图像处理软件,对钙质砂颗粒的内孔隙进行了定量分析。结果表明:较大颗粒钙质砂的内孔隙断面孔隙度相对较大,小孔隙数量较多,而大孔隙所占空间则较大;对于1 mm以上的钙质砂,缝隙状内孔隙含量远低于等轴或不等轴孔隙,等轴与不等轴内孔数量大致相等。%Calcareous sands are consisted of marine biogenic granular materials with carbonate content often greater than 50%. From the microscopic viewpoint, calcareous sand grains demonstrate highly angular and irregular in shapes and contain intra-pores. This unique intra-pore structure of calcareous sand particle is prone to crush under stress. Therefore, the calcareous sand has a relatively low strength. The intra-pore structure has a significant effect on the geotechnical properties of calcareous sands. Calcareous sand samples from the lagoon of Yongshu Reef atoll, Nansha Islands, were cut by femtosecond laser for the optical microscopic studies. The intra-pore structures were quantitatively analyzed throughout the MATLAB digital image process tool. The results indicate that, larger porosity can be found on the breakage section of larger size calcareous sand and a larger number of small pores with small total volume are in the intra-pore structure. For sand grains with a size greater than one millimeter, the number of slit shape intra-pores is far less than the number of intra-voids with equiaxed or unequal axed pores. The amount of the equiaxed and

  9. [Effects of different fertilizer application on soil active organic carbon].

    Science.gov (United States)

    Zhang, Rui; Zhang, Gui-Long; Ji, Yan-Yan; Li, Gang; Chang, Hong; Yang, Dian-Lin

    2013-01-01

    The variation characteristics of the content and components of soil active organic carbon under different fertilizer application were investigated in samples of calcareous fluvo-aquic soil from a field experiment growing winter wheat and summer maize in rotation in the North China Plain. The results showed that RF (recommended fertilization), CF (conventional fertilization) and NPK (mineral fertilizer alone) significantly increased the content of soil dissolved organic carbon and easily oxidized organic carbon by 24.92-38.63 mg x kg(-1) and 0.94-0.58 mg x kg(-1) respectively compared to CK (unfertilized control). The soil dissolved organic carbon content under OM (organic manure) increased greater than those under NPK and single fertilization, soil easily oxidized organic carbon content under OM and NPK increased greater than that under single chemical fertilization. OM and NPK showed no significant role in promoting the soil microbial biomass carbon, but combined application of OM and NPK significantly increased the soil microbial biomass carbon content by 36.06% and 20.69%, respectively. Soil easily oxidized organic carbon, dissolved organic carbon and microbial biomass carbon accounted for 8.41% - 14.83%, 0.47% - 0.70% and 0.89% - 1.20% of the total organic carbon (TOC), respectively. According to the results, the fertilizer application significantly increased the proportion of soil dissolved organic carbon and easily oxidized organic carbon, but there was no significant difference in the increasing extent of dissolved organic carbon. The RF and CF increased the proportion of soil easily oxidized organic carbon greater than OM or NPK, and significantly increased the proportion of microbial biomass carbon. OM or RF had no significant effect on the proportion of microbial biomass carbon. Therefore, in the field experiment, appropriate application of organic manure and chemical fertilizers played an important role for the increase of soil active organic carbon

  10. Soil carbon sequestration under long-term rice-based cropping systems of purple soil in Southwest China

    Institute of Scientific and Technical Information of China (English)

    FAN Hong-zhu; CHEN Qing-rui; QIN Yu-sheng; CHEN Kun; TU Shi-hua; XU Ming-gang; ZHANG Wen-ju

    2015-01-01

    Carbon sequestration in agricultural soils is a complex process controled by farming practices, climate and some other environment factors. Since purple soils are unique in China and used as the main cropland in Sichuan Basin of China, it is of great importance to study and understand the impacts of different fertilizer amendments on soil organic carbon (SOC) changes with time. A research was carried out to investigate the relationship between soil carbon sequestration and organic carbon input as affected by different fertilizer treatments at two long-term rice-based cropping system experiments set up in early 1980s. Each experiment consisted of six identical treatments, including (1) no fertilizer (CK), (2) nitrogen and phos-phorus fertilizers (NP), (3) nitrogen, phosphorus and potassium fertilizers (NPK), (4) fresh pig manure (M), (5) nitrogen and phosphorus fertilizers plus manure (MNP), and (6) nitrogen, phosphorus and potassium fertilizers plus manure (MNPK). The results showed that annual harvestable carbon biomass was the highest in the treatment of MNPK, folowed by MNP and NPK, then M and NP, and the lowest in CK. Most of fertilizer treatments resulted in a signiifcant gain in SOC ranging from 6.48 to 29.13% compared with the CK, and raised soil carbon sequestration rate to 0.10–0.53 t ha–1 yr−1. Especialy, addition of manure on the basis of mineral fertilizers was very conducive to SOC maintenance in this soil. SOC content and soil carbon sequestration rate under balanced fertilizer treatments (NPK and MNPK) in the calcareous purple soil (Suining) were higher than that in the acid purple soil (Leshan). But carbon conversion rate at Leshan was 11.00%, almost 1.5 times of that (7.80%) at Suining. Signiifcant linear correlations between soil carbon sequestration and carbon input were observed at both sites, signifying that the purple soil was not carbon-saturated and stil had considerable potential to sequestrate more carbon.

  11. Phytoavailability of cadmium (Cd) to Pak choi (Brassica chinensis L.) grown in Chinese soils: a model to evaluate the impact of soil Cd pollution on potential dietary toxicity.

    Science.gov (United States)

    Rafiq, Muhammad Tariq; Aziz, Rukhsanda; Yang, Xiaoe; Xiao, Wendan; Stoffella, Peter J; Saghir, Aamir; Azam, Muhammad; Li, Tingqiang

    2014-01-01

    Food chain contamination by soil cadmium (Cd) through vegetable consumption poses a threat to human health. Therefore, an understanding is needed on the relationship between the phytoavailability of Cd in soils and its uptake in edible tissues of vegetables. The purpose of this study was to establish soil Cd thresholds of representative Chinese soils based on dietary toxicity to humans and develop a model to evaluate the phytoavailability of Cd to Pak choi (Brassica chinensis L.) based on soil properties. Mehlich-3 extractable Cd thresholds were more suitable for Stagnic Anthrosols, Calcareous, Ustic Cambosols, Typic Haplustalfs, Udic Ferrisols and Periudic Argosols with values of 0.30, 0.25, 0.18, 0.16, 0.15 and 0.03 mg kg-1, respectively, while total Cd is adequate threshold for Mollisols with a value of 0.86 mg kg-1. A stepwise regression model indicated that Cd phytoavailability to Pak choi was significantly influenced by soil pH, organic matter, total Zinc and Cd concentrations in soil. Therefore, since Cd accumulation in Pak choi varied with soil characteristics, they should be considered while assessing the environmental quality of soils to ensure the hygienically safe food production.

  12. Soil quality evaluation following the implementation of permanent cover crops in semi-arid vineyards. Organic matter, physical and biological soil properties

    Energy Technology Data Exchange (ETDEWEB)

    Virto, I.; Imaz, M. J.; Fernandez-Ugalde, O.; Urrutia, I.; Enrique, A.; Bescansa, P.

    2012-07-01

    Changing from conventional vineyard soil management, which includes keeping bare soil through intense tilling and herbicides, to permanent grass cover (PGC) is controversial in semi-arid land because it has agronomic and environmental advantages but it can also induce negative changes in the soil physical status. The objectives of this work were (i) gaining knowledge on the effect of PGC on the soil physical and biological quality, and (ii) identifying the most suitable soil quality indicators for vineyard calcareous soils in semi-arid land. Key soil physical, organic and biological characteristics were determined in a Cambic Calcisol with different time under PGC (1 and 5 years), and in a conventionally managed control. Correlation analysis showed a direct positive relationship between greater aggregate stability (WSA), soil-available water capacity (AWC), microbial biomass and enzymatic activity in the topsoil under PGC. Total and labile organic C concentrations (SOC and POM-C) were also correlated to microbial parameters. Factor analysis of the studied soil attributes using principal component analysis (PCA) was done to identify the most sensitive soil quality indicators. Earthworm activity, AWC, WSA, SOC and POM-C were the soil attributes with greater loadings in the two factors determined by PCA, which means that these properties can be considered adequate soil quality indicators in this agrosystem. These results indicate that both soil physical and biological attributes are different under PGC than in conventionally-managed soils, and need therefore to be evaluated when assessing the consequences of PGC on vineyard soil quality. (Author) 65 refs.

  13. Water Quality, Hydrology, and Response to Changes in Phosphorus Loading of Nagawicka Lake, a Calcareous Lake in Waukesha County, Wisconsin

    Science.gov (United States)

    Garn, Herbert S.; Robertson, Dale M.; Rose, William J.; Goddard, Gerald L.; Horwatich, Judy A.

    2006-01-01

    Nagawicka Lake is a 986-acre, usually mesotrophic, calcareous lake in southeastern Wisconsin. Because of concern over potential water-quality degradation of the lake associated with further development in its watershed, a study was conducted by the U.S. Geological Survey from 2002 to 2006 to describe the water quality and hydrology of the lake; quantify sources of phosphorus, including those associated with urban development; and determine the effects of past and future changes in phosphorus loading on the water quality of the lake. All major water and phosphorus sources were measured directly, and minor sources were estimated to construct detailed water and phosphorus budgets for the lake. The Bark River, near-lake surface inflow, precipitation, and ground water contributed 74, 8, 12, and 6 percent of the inflow, respectively. Water leaves the lake primarily through the Bark River outlet (88 percent) or by evaporation (11 percent). The water quality of Nagawicka Lake has improved dramatically since 1980 as a result of decreasing the historical loading of phosphorus to the lake. Total input of phosphorus to the lake was about 3,000 pounds in monitoring year (MY) 2003 and 6,700 pounds in MY 2004. The largest source of phosphorus entering the lake was the Bark River, which delivered about 56 percent of the total phosphorus input, compared with about 74 percent of the total water input. The next largest contributions were from the urbanized near-lake drainage area, which disproportionately accounted for 37 percent of the total phosphorus input but only about 5 percent of the total water input. Simulations with water-quality models within the Wisconsin Lakes Modeling Suite (WiLMS) indicated the response of Nagawicka Lake to 10 phosphorus-loading scenarios. These scenarios included historical (1970s) and current (base) years (MY 2003-04) for which lake water quality and loading were known, six scenarios with percentage increases or decreases in phosphorus loading from

  14. Structure and Properties of Nanomaterials: From Inorganic Boron Nitride Nanotubes to the Calcareous Biomineralized Tubes of H. dianthus

    Science.gov (United States)

    Tanur, Adrienne Elizabeth

    Several nanomaterials systems, both inorganic and organic in nature, have been extensively investigated by a number of characterization techniques including atomic force microscopy (AFM), electron microscopy, Fourier transform infrared spectroscopy (FTIR), and energy dispersive x-ray spectroscopy (EDX). The first system consists of boron nitride nanotubes (BNNTs) synthesized via two different methods. The first method, silica-assisted catalytic chemical vapour deposition (SA-CVD), produced boron nitride nanotubes with different morphologies depending on the synthesis temperature. The second method, growth vapour trapping chemical vapour deposition (GVT-CVD), produced multiwall boron nitride nanotubes (MWBNNTs). The bending modulus of individual MWBNNTs was determined using an AFM three-point bending technique, and was found to be diameter-dependent due to the presence of shear effects. The second type of nanomaterial investigated is the biomineralized calcareous shell of the serpulid Hydroides dianthus. This material was found to be an inorganic-organic composite material composed of two different morphologies of CaCO3, collagen, and carboxylated and sulphated polysaccharides. The organic components were demonstrated to mediate the mineralization of CaCO3 in vitro. The final system studied is the proteinaceous cement of the barnacle Amphibalanus amphitrite. The secondary structure of the protein components was investigated via FTIR, revealing the presence of beta-sheet conformation, and nanoscale rod-shaped structures within the cement were identified as beta-sheet containing amyloid fibrils via chemical staining. These rod-shaped structures exhibited a stiffer nature compared with other structures in the adhesive, as measured by AFM nanoindentation.

  15. Authigenic potassium feldspar: a tracer for the timing of palaeofluid flow in carbonate rocks, Northern Calcareous Alps, Austria

    Science.gov (United States)

    Spotl, C.; Kunk, M.J.; Ramseyer, K.; Longstaffe, F.J.

    1998-01-01

    This paper is included in the Special Publication entitled 'Dating and duration of fluid flow and fluid-rock interaction', edited by J. Parnell. Feldspar is a common authigenic constituent in Permian carbonate rocks which occur as tectonically isolated blocks within the evaporitic Haselgebirge melange in the Northern Calcareous Alps (NCA). Coexisting with pyrite, anhydrite, (saddle) dolomite, magnesite, fluorite and calcite, K-feldspar and minor albite record an event of regionally extensive interaction of hot brines with carbonate rocks. Detailed petrographic, crystallographic and geochemical studies reveal a variability in crystal size and shape, Al-Si ordering, elemental and stable isotopic compositions of the K-feldspar, which is only partially consistent with the traditional view of authigenic feldspar as a well-ordered, compositionally pure mineral. 40Ar-39Ar step- heating measurements of authigenic potassium feldspar from several localities yield two age populations, an older one of 145-154 Ma, and a younger one of c.90-97 Ma. Most age spectra reflect cooling through the argon retention temperature interval, which was rapid in some localities (as indicated by plateau ages) and slower in others. Rb-Sr isotope data are more difficult to interpret, because in many K-feldspar samples they are controlled largely by Sr-bearing inclusions. The Jurassic 40Ar-39Ar dates are interpreted as minimum ages of feldspar growth and hence imply that fluid-rock interaction is likely to be simultaneous with or to slightly predate melange formation. Deformation associated with the closure and subduction of the Meliata-Hallstatt ocean south of the NCA during the Upper Jurassic is regarded as the principal geodynamic driving force for both enhanced fluid circulation and melange formation. Some localities were reheated beyond the argon retention temperature for microcline during mid-Cretaceous nappe stacking of the NCA, thus obliterating the older signal.

  16. On the peritidal cycles and their diagenetic evolution in the Lower Jurassic carbonates of the Calcare Massiccio Formation (Central Apennines

    Directory of Open Access Journals (Sweden)

    Brandano Marco

    2015-10-01

    Full Text Available This paper shows the environmental changes and high-frequency cyclicity recorded by Lower Jurassic shallow-water carbonates known as the Calcare Massiccio Formation which crop out in the central Apennines of Italy. Three types of sedimentary cycle bounded by subaerial erosion have been recognized: Type I consists of a shallowing upward cycle with oncoidal floatstones to rudstones passing gradationally up into peloidal packstone alternating with cryptoalgal laminites and often bounded by desiccation cracks and pisolitic-peloidal wackestones indicating a period of subaerial exposure. Type II shows a symmetrical trend in terms of facies arrangement with peloidal packstones and cryptoalgal laminites present both at the base and in the upper portion of the cycle, separated by oncoidal floatstones to rudstones. Type III displays a shallowing upward trend with an initial erosion surface overlain by oncoidal floatstones to rudstones that, in turn, are capped by pisolitic-peloidal wackestones and desiccation sheet cracks. Sheet cracks at the top of cycles formed during the initial phase of subaerial exposure were successively enlarged by dissolution during prolonged subaerial exposure. The following sea-level fall produced dissolution cavities in subtidal facies, while the successive sea-level rise resulted in the precipitation of marine cements in dissolution cavities. Spectral analysis revealed six peaks, five of which are consistent with orbital cycles. While a tectonic control cannot be disregarded, the main signal recorded by the sedimentary succession points toward a main control related to orbital forcing. High frequency sea-level fluctuations also controlled diagenetic processes.

  17. Soil microbial toxicity assessment of a copper-based fungicide in two contrasting soils

    Science.gov (United States)

    Dober, Melanie; Deltedesco, Evi; Jöchlinger, Lisa; Schneider, Martin; Gorfer, Markus; Bruckner, Alexander; Zechmeister-Boltenstern, Sophie; Soja, Gerhard; Zehetner, Franz; Keiblinger, Katharina Maria

    2016-04-01

    The infestation with the fungus downy mildew (Plasmopara viticola) causes dramatic losses in wine production. Copper (Cu) based fungicides have been used in viticulture since the end of the 19th century, and until today both conventional and organic viticulture strongly rely on Cu to prevent and reduce fungal diseases. Consequently, Cu has built up in many vineyard soils and it is still unclear how this affects soil functioning. The aim of the present study is the evaluation of the soil microbial toxicity of Cu contamination. Two contrasting agricultural soils, an acidic sandy soil and a calcareous loamy soil, were sampled to conduct an eco-toxicological greenhouse pot experiment. The soils were spiked with a commonly used fungicide based on copper hydroxid in seven concentrations (0, 50, 100, 200, 500, 1500 and 5000 mg Cu kg-1 soil) and Lucerne (Medicago sativa L. cultivar. Plato) was grown in the pots for 3 months. Sampling was conducted at the beginning and at the end of the study period to test copper's soil microbial toxicity in total microbial biomass and basal respiration, as well as enzyme activities, such as exoglucanase, β-glucosidase, exochitinase, phosphatase, protease, phenol-, peroxidase and urease. Additionally, DOC, TN, Cmic, Nmic, NO3 and NH4 were determined to provide further insight into the carbon and nitrogen cycle. Microbial community structure was analysed by phospholipid fatty acids (PLFAs), and ergosterol as a fungal biomarker. In addition, molecular tools were applied by extracting soil DNA and performing real time quantitative polymerase chain reaction (qPCR) and a metagenomic approach using 16S and ITS amplification and sequencing with MiSeq platform for the second sampling. Hydrolytic extracellular enzymes were not clearly affected by rising Cu concentrations, while a trend of increasing activity of oxidative enzymes (phenol- and peroxidase) was observed. Microbial respiration rate as well as the amount of Cmic and Nmic decreased with

  18. Humus-assisted cleaning of heavy metal contaminated soils

    Science.gov (United States)

    Borggaard, Ole K.; Rasmussen, Signe B.

    2016-04-01

    Contamination of soils with non-degradable heavy metals (HMs) because of human acticities is globally a serious problem threatening human health and ecosystem functioning. To avoid negative effects, HMs must be removed either on-site by plant uptake (phytoremediation) or off-site by extraction (soil washing). In both strategies, HM solubility must be augmented by means of a strong ligand (complexant). Often polycarboxylates such as EDTA and NTA are used but these ligands are toxic, synthetic (non-natural) and may promote HM leaching. Instead naturally occurring soluble humic substances (HS) were tested as means for cleaning HM contaminated soils; HS samples from beech and spruce litter, compost percolate and processed cow slurry were tested. Various long-term HM contaminated soils were extracted with solutions of EDTA, NTA or HS at different pH by single-step and multiple-step extraction mode. The results showed that each of the three complexant types increased HM solubility but the pH-dependent HM extraction efficiency decreased in the order: EDTA ≈ NTA > HS. However, the naturally occurring HS seems suitable for cleaning As, Cd, Cu and Zn contaminated soils both in relation to phytoremediation of moderately contaminated soils and washing of strongly contaminated soils. On the other hand, HS was found unsuited as cleaning agent for Pb polluted calcareous soils. If future field experiments confirm these laboratory results, we have a new cheap and environmentally friendly method for solving a great pollution problem, i.e. cleaning of heavy metal contaminated soils. In addition, humic substances possess additional benefits such as improving soil structure and stimulating microbial activity.

  19. 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.

  20. Effect of Soil Moisture on Release of Low-MolecularWeight Organic Acids in Root Exudates and the Accumulation of Iron in Root Apoplasm of Peanut

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    A three-compartments rhizobox was designed and used to study the low-molecular-weight organic acids in root exudates and the root apoplastic iron of "lime-induced chlorosis" peanut grown on a calcareous soil in relation to different soil moisture conditions. Results showed that chlorosis of peanuts developed under condition of high soil moisture level (250 g kg-1), while peanuts grew well and chlorosis did not develop when soil moisture was managed to a normal level (150 g kg-1). The malic acid, maleic acid and succinic acid contents of chlorotic peanut increased by 108.723, 0.029 and 22.446μg cm-2, respectively,compared with healthy peanuts. The content of citric acid and fumaric acid also increased in root exudates of chlorotic peanuts. On Days 28 and 42 of peanut growth, the accumulation of root apoplastic iron in chlorotic peanuts was higher than that of healthy peanuts. From Day 28 to Day 42, the mobilization percentages of chlorotic peanuts and healthy peanuts to root apoplastic iron were almost the same, being 52.4% and 52.8%,respectively, indicating that the chlorosis might be caused by the inactivation of iron within peanut plant grown on a calcareous soil under high soil moisture conditions.

  1. Calcareous nannofossils of the Toarcian-Aalenian transition in the São Gião section (Lusitanian Basin, Portugal): preliminary results

    Science.gov (United States)

    Cortesão, André; Henriques, Maria Helena

    2016-04-01

    This work presents preliminary results regarding the composition of the calcareous nannofossils assemblages' recorded in the Lower-Middle Jurassic transition of the São Gião section, located in the northern Lusitanian Basin (Central Portugal). The section is a 45 m-thick monotonous alternation of marl and marly limestone (the Póvoa da Lomba Formation) ranging from the Upper Toarcian to the Lower Aalenian, and it corresponds to an expanded section showing exceptional exposure conditions. The continuous record of ammonites has enabled the recognition of the Aalensis Zone (Mactra and Aalensis subzones) and the Opalinum Zone (Opalinum and Comptum subzones). The abundant and very diverse benthic foraminiferal record accurately calibrated with the ammonite record has allowed the recognition of the Astacolus dorbignyi Zone. For the study of the calcareous nannofossil record, four samples were collected (one for each ammonite subzone) and processed; the smear slides were analyzed in a Leica DM750P polarizing microscope, using a 1000 X magnification. The nannfossil assemblages of the São Gião section are dominated by representatives of the genera Lotharingius and Discorhabdus, whereas Carinolithus and Schizosphaerella are subordinated. Other genera also represented in the analysed assemblages include Crepidolithus and Thoracosphaera. As noticed for the ammonite and for the benthic foraminiferal record, throughout the Upper Toarcian - Lower Aalenian record for the São Gião section no drastic changes in the number of originations and extinctions of nannofossil genera between ammonite biozones was detected. The main faunal change is the increase in the relative abundance of the genera Carinolithus in the Comptum Subzone, and the concomitant reduction of the relative abundance of Discorhabdus, but Lotharingius representatives remain dominant during the whole Upper Toarcian - Lower Aalenian transition. Further developments on this study will contribute to elaborate an

  2. Stable isotope and calcareous nannofossil assemblage records for the Cicogna section: toward a detailed template of late Paleocene and early Eocene global carbon cycle and nannoplankton evolution

    Directory of Open Access Journals (Sweden)

    C. Agnini

    2015-09-01

    Full Text Available We present records of stable carbon and oxygen isotopes, CaCO3 content, and changes in calcareous nannofossil assemblages across an 81 m thick section of upper Paleocene-lower Eocene marine sedimentary rocks now exposed along Cicogna Stream in northeast Italy. The studied stratigraphic section represents sediment accumulation in a bathyal hemipelagic setting from approximately 57.5 to 52.2 Ma, a multi-million-year time interval characterized by perturbations in the global carbon cycle and changes in calcareous nannofossil assemblages. The bulk carbonate δ13C profile for the Cicogna section, once placed on a common time scale, resembles that at several other locations across the world, and includes both a long-term drop in δ13C, and multiple short-term carbon isotope excursions (CIEs. This precise correlation of widely separated δ13C records in marine sequences results from temporal changes in the carbon composition of the exogenic carbon cycle. However, diagenesis has likely modified the δ13C record at Cicogna, an interpretation supported by variations in bulk carbonate δ18O, which do not conform to expectations for a primary signal. The record of CaCO3 content reflects a combination of carbonate dilution and dissolution, as also inferred at other sites. Our detailed documentation and statistical analysis of calcareous nannofossil assemblages show major differences before, during and after the Paleocene Eocene Thermal Maximum. Other CIEs in our lower Paleogene section do not exhibit such a distinctive change; instead, these events are sometimes characterized by variations restricted to a limited number of taxa and transient shifts in the relative abundance of primary assemblage components. Both long-lasting and short-lived modifications to calcareous nannofossil assemblages preferentially affected nannoliths or holococcoliths such as Discoaster, Fasciculithus, Rhomboaster/Tribrachiatus, Spenolithus and Zygrhablithus, which underwent

  3. Growth of Photosynthetic Biofilms and Fe, Pb, Cu, and Zn Speciation in Unsaturated Columns with Calcareous Mine Tailings from Arid Zones

    Directory of Open Access Journals (Sweden)

    J. V. García-Meza

    2011-01-01

    Full Text Available Mine tailing remediation aims to reduce the rate of sulfide mineral oxidation. Earlier studies showed that photosynthetic biofilms may act as a physical barrier against oxygen diffusion. Currently, a long-term assay (6 months is required to evaluate the solid phase redistribution of the Pb, Fe, Cu, and Zn originally present in historic and calcareous mine tailing samples (in our case from a semiarid region in North-Central Mexico. The presence of biofilms may provide chemical gradients and physical conditions that shift the proportion of Fe, Cu, and Zn originally associated with oxides to carbonates and organic matter/sulfide fractions.

  4. Stable isotope and calcareous nannofossil assemblage records for the Cicogna section: toward a detailed template of late Paleocene and early Eocene global carbon cycle and nannoplankton evolution

    Science.gov (United States)

    Agnini, C.; Spofforth, D. J. A.; Dickens, G. R.; Rio, D.; Pälike, H.; Backman, J.; Muttoni, G.; Dallanave, E.

    2015-09-01

    We present records of stable carbon and oxygen isotopes, CaCO3 content, and changes in calcareous nannofossil assemblages across an 81 m thick section of upper Paleocene-lower Eocene marine sedimentary rocks now exposed along Cicogna Stream in northeast Italy. The studied stratigraphic section represents sediment accumulation in a bathyal hemipelagic setting from approximately 57.5 to 52.2 Ma, a multi-million-year time interval characterized by perturbations in the global carbon cycle and changes in calcareous nannofossil assemblages. The bulk carbonate δ13C profile for the Cicogna section, once placed on a common time scale, resembles that at several other locations across the world, and includes both a long-term drop in δ13C, and multiple short-term carbon isotope excursions (CIEs). This precise correlation of widely separated δ13C records in marine sequences results from temporal changes in the carbon composition of the exogenic carbon cycle. However, diagenesis has likely modified the δ13C record at Cicogna, an interpretation supported by variations in bulk carbonate δ18O, which do not conform to expectations for a primary signal. The record of CaCO3 content reflects a combination of carbonate dilution and dissolution, as also inferred at other sites. Our detailed documentation and statistical analysis of calcareous nannofossil assemblages show major differences before, during and after the Paleocene Eocene Thermal Maximum. Other CIEs in our lower Paleogene section do not exhibit such a distinctive change; instead, these events are sometimes characterized by variations restricted to a limited number of taxa and transient shifts in the relative abundance of primary assemblage components. Both long-lasting and short-lived modifications to calcareous nannofossil assemblages preferentially affected nannoliths or holococcoliths such as Discoaster, Fasciculithus, Rhomboaster/Tribrachiatus, Spenolithus and Zygrhablithus, which underwent distinct variations in

  5. Contact angles at the water-air interface of hydrocarbon-contaminated soils and clay minerals

    Science.gov (United States)

    Sofinskaya, O. A.; Kosterin, A. V.; Kosterina, E. A.

    2016-12-01

    Contact angles at the water-air interface have been measured for triturated preparations of clays and soils in order to assess changes in their hydrophobic properties under the effect of oil hydrocarbons. Tasks have been to determine the dynamics of contact angle under soil wetting conditions and to reveal the effect of chemical removal of organic matter from soils on the hydrophilicity of preparations. The potentialities of static and dynamic drop tests for assessing the hydrophilic-hydrophobic properties of soils have been estimated. Clays (kaolinite, gumbrine, and argillite) have been investigated, as well as plow horizons of soils from the Republic of Tatarstan: heavy loamy leached chernozem, medium loamy dark gray forest soil, and light loamy soddy-calcareous soil. The soils have been contaminated with raw oil and kerosene at rates of 0.1-3 wt %. In the uncontaminated and contaminated chernozem, capillary water capacity has been maintained for 250 days. The contact angles have been found to depend on the degree of dispersion of powdered preparation, the main type of clay minerals in the soil, the presence and amount of oxidation-resistant soil organic matter, and the soil-water contact time. Characteristic parameters of mathematical models for drop behavior on triturated preparations have been calculated. Contamination with hydrocarbons has resulted in a reliable increase in the contact angles of soil preparations. The hydrophobization of soil surface in chernozem is more active than in soils poorer in organic matter. The complete restoration of the hydrophilic properties of soils after hydrocarbon contamination is due to the oxidation of easily oxidizable organic matter at the low content of humus, or to wetting during several months in the absence of the mazut fraction.

  6. Influence of vermicomposting on solid wastes decomposition kinetics in soils

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The effect of vermicomposting on kinetic behavior of the products is not well recognized. An incubation study was conducted to investigate C mineralization kinetics of cow manure, sugarcane filter cake and their vermicomposts. Two different soils were treated with the four solid wastes at a rate of 0.5 g solid waste C per kg soil with three replications. Soils were incubated for 56 d. The CO2-C respired was monitored periodically and a first-order kinetic model was used to calculate the kinetic parameters of C mineralization. Results indicated that the percentage of C mineralized during the incubation period ranged from 31.9% to 41.8% and 55.9% to 73.4% in the calcareous and acidic soils, respectively. The potentially mineralizable C (C0) of the treated soils was lower in the solid waste composts compared to their starting materials. Overall, it can be concluded that decomposable fraction of solid wastes has decreased due to vermicomposting.

  7. Soil formation.

    NARCIS (Netherlands)

    Breemen, van N.; Buurman, P.

    1998-01-01

    Soil Formation deals with qualitative and quantitative aspects of soil formation (or pedogenesis) and the underlying chemical, biological, and physical processes. The starting point of the text is the process - and not soil classification. Effects of weathering and new formation of minerals, mobilis

  8. Effect of soil-rock system on speleothems weathering in Bailong Cave, Yunnan Province, China

    Institute of Scientific and Technical Information of China (English)

    WANG Jing; SONG Lin-hua

    2005-01-01

    Bailong Cave with its well-developed Middle Triassic calcareous dolomite's system was opened as a show cave for visitors in 1988. The speleothem scenery has been strongly weathered as white powder on the outer layers. Study of the cave winds, permeability of soil-rock system and the chemical compositions of the dripping water indicated: (1) The cave dimension structure distinctively affects the cave winds, which were stronger at narrow places. (2) Based on the different soil grain size distribution, clay was the highest in composition in the soil. The response sense of dripping water to the rainwater percolation was slow. The density of joints and other openings in dolomite make the dolomite as mesh seepage body forming piles of thin and high columns and stalactites. (3) Study of 9 dripping water samples by HYDROWIN computer program showed that the major mineral in the water was dolomite.

  9. Soil metagenomics and tropical soil productivity

    OpenAIRE

    Karen A Garrett

    2009-01-01

    This presentation summarizes research in the soil metagenomics cross cutting research activity. Soil metagenomics studies soil microbial communities as contributors to soil health.C CCRA-4 (Soil Metagenomics)

  10. Soils - Volusia County Soils (Polygons)

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — Soils: 1:24000 SSURGO Map. Polygon boundaries of Soils in Volusia County, downloaded from SJRWMD and created by NRCS and SJRWMD. This data set is a digital version...

  11. Soil types will alter the response of arable agroecosystems to future rainfall patterns

    Science.gov (United States)

    Zaller, J. G.; Schwarz, T.; Hall, R.; Ziss, E.; von Hohberg und Buchwald, C.; Hösch, J.; Baumgarten, A.

    2012-04-01

    Regional climate change scenarios for eastern Austria (pannonian region) predict fewer but heavier rains during the vegetation period without substantial changes in the total annual amount of rainfall. While many studies investigated the effects of rainfall patterns on ecosystem properties, very little is known on how different soil types might alter ecosystem responses. In order to test this, we conducted an experiment at the AGES lysimeter station using 18 3 m2 lysimeters where we simultaneously manipulated rainfall patterns according to regional climate scenarios (current vs. prognosticated rain) on the three main soil types of the region (sandy calcaric phaeozem, gleyic phaeozem and calcic chernozem). Lysimeters were cultivated according to good farming practice using crop varieties and crop rotations typically for the region. Here, we present results of the response of field peas (Pisum sativum) on important agricultural parameters. Lysimeters under progn. rain showed lower crop cover than under curr. rain while soil types had no effect. Total aboveground biomass production (comprising crops plus weeds) was significantly lower under progn. rain; sandy calcaric phaeozem showed the lowest plant biomass. Pea yields under progn. rain were substantially lower than under curr. rain; again, yields under sandy soils were lower than under the other two soil types. Root growth was significantly higher in progn. rain than in curr. rain; there was a trend towards less root growth in the gleyic soils. Mycorrhization of roots was not influenced by soil types, however under progn. rain colonization rates were lower than under curr. rain. Weed establishment and growth was increased under progn. rain in gleyic soils but decreased in the other soil types. Weed biomass was not affected by rainfall, however sandy soils had less weed biomass than the other soil types. Abundance of the insect pest pea moth (Cydia nigricana) was almost twice as high under progn. rain than under curr

  12. Soil infiltrometer

    Energy Technology Data Exchange (ETDEWEB)

    Mehler, M.R.

    1990-09-18

    This patent describes an infiltrometer useful for field testing soil permeability. It comprises: a large reservoir having an open bottom resting on the soil; a small reservoir having an open bottom resting on the soil, the small reservoir being positioned within the large reservoir; the small reservoir comprising a relatively large receptacle adjacent the soil and a relatively small receptacle connected thereto and extending upwardly therefrom; the volume of the large reservoir greatly exceeding the volume of the small reservoir; the ratio of the upper surface area of liquid in the large reservoir to the surface area of the soil covered thereby greatly exceeding the ratio of the upper surface area of liquid in the relatively small receptacle of the small reservoir to the surface area of the soil covered thereby; and means for determining the amount of liquid from the small reservoir permeating into the soil.

  13. Common genetic denominators for Ca++-based skeleton in Metazoa: role of osteoclast-stimulating factor and of carbonic anhydrase in a calcareous sponge.

    Directory of Open Access Journals (Sweden)

    Werner E G Müller

    Full Text Available Calcium-based matrices serve predominantly as inorganic, hard skeletal systems in Metazoa from calcareous sponges [phylum Porifera; class Calcarea] to proto- and deuterostomian multicellular animals. The calcareous sponges form their skeletal elements, the spicules, from amorphous calcium carbonate (ACC. Treatment of spicules from Sycon raphanus with sodium hypochlorite (NaOCl results in the disintegration of the ACC in those skeletal elements. Until now a distinct protein/enzyme involved in ACC metabolism could not been identified in those animals. We applied the technique of phage display combinatorial libraries to identify oligopeptides that bind to NaOCl-treated spicules: those oligopeptides allowed us to detect proteins that bind to those spicules. Two molecules have been identified, the (putative enzyme carbonic anhydrase and the (putative osteoclast-stimulating factor (OSTF, that are involved in the catabolism of ACC. The complete cDNAs were isolated and the recombinant proteins were prepared to raise antibodies. In turn, immunofluorescence staining of tissue slices and qPCR analyses have been performed. The data show that sponges, cultivated under standard condition (10 mM CaCl(2 show low levels of transcripts/proteins for carbonic anhydrase or OSTF, compared to those animals that had been cultivated under Ca(2+-depletion condition (1 mM CaCl(2. Our data identify with the carbonic anhydrase and the OSTF the first two molecules which remain conserved in cells, potentially involved in Ca-based skeletal dissolution, from sponges (sclerocytes to human (osteoclast.

  14. Role of Low-Molecule-Weight Organic Acids and Their Salts in Regulating Soil pH

    Institute of Scientific and Technical Information of China (English)

    LI Zhi-An; ZOU Bi; XIA Han-Ping; DING Yong-Zhen; TAN Wan-Neng; FU Sheng-Lei

    2008-01-01

    The process of organic materials increasing soil pH has not yet been fully understood.This study examined the role of cations and organic anions in regulating soil pH using organic compounds.Calcareous soil,acid soil,and paddy soil were incubated with different simple organic compounds,pH was determined periodically and CO2 emission was also measured.Mixing organic acids with the soil caused an instant decrease of soil pH.The magnitude of pH decrease depended on the initial soil acidity and dissociation degree of the acids.Decomposition of organic acids could only recover the soil pH to about its original level.Mixing organic salts with soil caused an instant increase of soil pH.Decomposition of organic salts of sodium resulted in a steady increase of soil pH,with final soil pH being about 2.7-3.2 pH units over the control.Organic salts with the same anions (citrate) but different cations led to different magnitudes of pH increase,while those having the same cations but different anions led to very similar pH increases.Organic salts of sodium and sodium carbonate caused very similar pH increases of soil when they were added to the acid soil at equimolar concentrations of Na+.The results suggested that cations played a central role in regulating soil pH.Decarboxylation might only consume a limited number of protons.Conversion of organic salts into inorganic salts (carbonate) was possibly responsible for pH increase during their decomposition,suggesting that only those plant residues containing high excess base cations could actually increase soil pH.

  15. Influence of Soil Organic Matter Content on Abundance and Biomass of Earthworm (Oligochaeta: Lumbricidae Populations

    Directory of Open Access Journals (Sweden)

    Hristo Valchovski

    2016-06-01

    Full Text Available The current study explores the influence of soil organic matter content on abundance and biomass of earthworm communities. The observation was carried out on three type of soils: PellicVertisols (very fine texture, Cromi-Vertic Luvisols (fine texture and Calcaric Fluvisols (mediumtexture from the Balkan Peninsula (Bulgaria. The field experiment was provided on uncultivatedplots. In the studied area earthworm fauna comprises of four species: Aporrectodea rosea,Aporrectodea caliginosa, Lumbricus terrestris and Octolasion lacteum. We found peregrine lumbricidtaxa, which are widely distributed in European soils. Our study demonstrated that soil organicmatter has a positive effect on lumbricid populations. It was revealed that augmentation of soilorganic matter favours characteristics of earthworm communities. The soil organic matter contentand earthworm abundance are in strong positive correlation (r > 0.981. The same relationship wasrevealed between the biomass of lumbricid fauna and amount of soil organic matter (r > 0.987. Insum, the soil organic matter could be used as an indicator for earthworm communities inuncultivated soils.

  16. Is it real or apparent increased aggregate stability sometimes found in burned soils?

    Directory of Open Access Journals (Sweden)

    V. Arcenegui

    2013-05-01

    Full Text Available The increase in soil aggregate stability observed in many cases after burning is discussed in this paper. Soil samples under pine forest from two Mediterranean areas were collected for this experiment: acid soils from El Algibe Range (Los Alcornocales Natural Park, Cádiz, Southern Spain and calcareous soils of Sierra de la Grana (Alicante, Eastern Spain. In each case, soil aggregates (2 to 0.25 mm were selected and exposed to temperatures of 200, 250, 300, 500 and 700 oC during a 20-minutes period. In both cases weight loss after volatilization of substances and a significant destruction of aggregates with increasing temperature were observed. For acid soils, where organic matter is the main cementing agent, destruction of aggregates with temperature was more intense. Water repellency induced by combustion increased between 200 and 250 oC, also the remaining aggregates remaining increased within the initial size fraction after heating, increasing its stability. For temperatures above 300 oC, water repellency disappeared, although an increase in aggregate stability was observed, possibly due to changes in the mineral soil fraction. Therefore, it is concluded that burning may destroy part of the aggregates by combustion of organic matter, so selecting stable aggregates. Water repellency and transformations of soil minerals contribute to increased stability in selected aggregates.

  17. Bulk soil and rhizosphere bacterial community PCR-DGGE profiles and beta-galactosidase activity as indicators of biological quality in soils contaminated by heavy metals and cultivated with Silene vulgaris (Moench) Garcke.

    Science.gov (United States)

    Martínez-Iñigo, M J; Pérez-Sanz, A; Ortiz, I; Alonso, J; Alarcón, R; García, P; Lobo, M C

    2009-06-01

    The biological quality of two heavy metal contaminated soils (soil C: Typic Calcixerept, pH 8.3 and soil H: Typic Haploxeraf, pH 7.3) was investigated after growing the metal-tolerant plant Silene vulgaris (Moench) Garcke for two vegetative periods. The activity of the enzyme beta-galactosidase, which is sensitive to the presence of contaminants in soil, and the polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) profiles of 16S rRNA gene fragments of culturable bacteria from bulk soil and rhizosphere were determined. The microbial enzymatic activity was higher in planted soils than in bare soils at the contamination level of 600 mg of total heavy metals kg(-1) soil. After growing S. vulgaris, beta-galactosidase activity was almost recovered in the calcareous soil. In this soil new bands appeared in the PCR-DGGE profiles of the rhizosphere bacterial community as a response to the exposure to heavy metals.

  18. The Comparison of Olsen, DMT-HFO and DGT Methods for Assessment of Plant Available Phosphorus in Soils

    Directory of Open Access Journals (Sweden)

    Saber Heidari

    2016-01-01

    Full Text Available Phosphorus (P is one of the most important limiting nutrients for crop production in the world soils. Excessive and deficiencies of P in calcareous soils has been reported. Several methods can be used to recognize soil bioavailable phosphorus. Soil P tests involve chemical extraction and ion-sink extractants. The diffusive gradient in thin-films (DGT is a new technique for measuring available soil phosphorus. This technique attempts to simulate physico-chemical processes influencing the uptake of solutes by plant roots. Also, the dialysis membrane tubes filled with hydrous ferric oxide solution (DMT-HFO has recently been used to assess P desorption over long-term laboratory studies. The DMT-HFO method acts like the DGT method. Both systems are based on Fick’s law and try to imitate physicochemical uptake of P by plant roots in soils. The aim of this research was to use Fick’s law in the interpretation of DMT measurements and compare it with the Olsen and DGT methods for assessment of corn available phosphorus in some calcareous soils. For this purpose, the diffusion coefficients of P in the DMT membrane and DGT gel were calculated. The DMT-HFOs were located in soil suspensions at 24, 72, 240, and 500 hours and the concentration of DMT-HFO (CDMT-HFO for P in the mentioned times were compared with those of Olsen and DGT methods on assessing of corn P uptake. Corn (SC 704 were grown in a greenhouse on ten different calcareous soils. Based on the results, the diffusion coefficient of P (H2PO4- in DMT (5.54*10-8 cm2.s-1was lower than that of DGT gel (5.8*10-6 cm2.s-1. The linear correlation coefficient(r between CDMT-HFO and corn P content was increased by the time (24- 500 hours. Based on the r2 values, the lowest and highest correlations were related to CDMT-HFO in 24 hours (r2=0.22, p<0.05 and 500 hours (r2=0.9, p<0.05, respectively. The DMT-HFO provides a more precise correlation with P uptake by corn (r2=0.9 in 500 hours than Olsen P (r2

  19. Effect of Phopshate Fertilizer and Manure on Crop Yield, Soil P Accumulation, and the Environmental Risk Assessment

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Phosphorus (P) applied from fertilizer and manure is important in increasing crop yield and soil fertility; however, excessive uses of phosphate fertilizer and manure may also increase P loss from agricultural soils, posing environmental impact. A long term experiment was conducted on a calcareous soil (meadow cinnamon) in Hebei Province, China, from 2003 to 2006 to investigate the effects of phosphate fertilizer and manure on the yield of Chinese cabbage, soil P accumulation, P sorption saturation, soluble P in runoff water, and P leaching. P fertilizer (P2O5) application at a rate of 360 kg ha-1 or manure of 150 t ha-1 significantly increased Chinese cabbage yield as compared to the unfertilized control. However, no significant yield response was found with excessive phosphate or manure application. Soil Olsen-P, soluble P, bioavailable P, the degree of phosphorus sorption saturation in top soil layer (0-20 cm), and soluble P in runoff water increased significantly with the increase of phosphate fertilizer and manure application rates, whereas the maximum phosphorus sorption capacity (Qm) decreased with the phosphate fertilizer and manure application rates. Soil Olsen-P and soluble P also increased significantly in the sub soil layer (20-40 cm) with the high P fertilizer and manure rates. It indicates that excessive P application over crop demand can lead to a high environmental risk owing to the enrichment of soil Olsen-P, soluble P,bioavailable P, and the degree of phosphorus sorption saturation in agricultural soils.

  20. Organic matter losses in German Alps forest soils since the 1970s most likely caused by warming

    Science.gov (United States)

    Prietzel, Jörg; Zimmermann, Lothar; Schubert, Alfred; Christophel, Dominik

    2016-07-01

    Climate warming is expected to induce soil organic carbon losses in mountain soils that result, in turn, in reduced soil fertility, reduced water storage capacity and positive feedback on climate change. Here we combine two independent sets of measurements of soil organic carbon from forest soils in the German Alps--repeated measurements from 1976 to 2010 and from 1987 to 2011--to show that warming has caused a 14% decline in topsoil organic carbon stocks. The decreases in soil carbon occurred over a period of significant increases in six-month summer temperatures, with the most substantial decreases occurring at sites with large changes in mean annual temperature. Organic carbon stock decreases were largest--on average 32%--in forest soils with initial topsoil organic carbon stocks greater than 8 kg C m-2, which can be found predominantly on calcareous bedrock. However, organic carbon stocks of forest soils with lower initial carbon stocks, as well as soils under pasture or at elevations above 1,150 m, have not changed significantly. We conclude that warming is the most likely reason for the observed losses of soil organic carbon, but that site, land use and elevation may ameliorate the effects of climate change.

  1. Organic carbon stocks and sequestration rates of forest soils in Germany.

    Science.gov (United States)

    Grüneberg, Erik; Ziche, Daniel; Wellbrock, Nicole

    2014-08-01

    The National Forest Soil Inventory (NFSI) provides the Greenhouse Gas Reporting in Germany with a quantitative assessment of organic carbon (C) stocks and changes in forest soils. Carbon stocks of the organic layer and the mineral topsoil (30 cm) were estimated on the basis of ca. 1.800 plots sampled from 1987 to 1992 and resampled from 2006 to 2008 on a nationwide grid of 8 × 8 km. Organic layer C stock estimates were attributed to surveyed forest stands and CORINE land cover data. Mineral soil C stock estimates were linked with the distribution of dominant soil types according to the Soil Map of Germany (1 : 1 000 000) and subsequently related to the forest area. It appears that the C pool of the organic layer was largely depending on tree species and parent material, whereas the C pool of the mineral soil varied among soil groups. We identified the organic layer C pool as stable although C was significantly sequestered under coniferous forest at lowland sites. The mineral soils, however, sequestered 0.41 Mg C ha(-1) yr(-1) . Carbon pool changes were supposed to depend on stand age and forest transformation as well as an enhanced biomass input. Carbon stock changes were clearly attributed to parent material and soil groups as sandy soils sequestered higher amounts of C, whereas clayey and calcareous soils showed small gains and in some cases even losses of soil C. We further showed that the largest part of the overall sample variance was not explained by fine-earth stock variances, rather by the C concentrations variance. The applied uncertainty analyses in this study link the variability of strata with measurement errors. In accordance to other studies for Central Europe, the results showed that the applied method enabled a reliable nationwide quantification of the soil C pool development for a certain period.

  2. Soil disturbance as a grassland restoration measure-effects on plant species composition and plant functional traits.

    Directory of Open Access Journals (Sweden)

    Tim Schnoor

    Full Text Available Soil disturbance is recognized as an important driver of biodiversity in dry grasslands, and can therefore be implemented as a restoration measure. However, because community re-assembly following disturbance includes stochastic processes, a focus only on species richness or establishment success of particular species will not inform on how plant communities respond ecologically to disturbance. We therefore evaluated vegetation development following disturbance by quantifying species richness, species composition and functional trait composition. Degraded calcareous sandy grassland was subjected to experimental disturbance treatments (ploughing or rotavation, and the vegetation was surveyed during four subsequent years of succession. Treated plots were compared with control plots representing untreated grassland, as well as nearby plots characterized by plant communities representing the restoration target. Species richness and functional diversity both increased in response to soil disturbance, and rotavation, but not ploughing, had a persistent positive effect on the occurrence of specialist species of calcareous sandy grassland. However, no type of soil disturbance caused the plant species composition to develop towards the target vegetation. The disturbance had an immediate and large impact on the vegetation, but the vegetation developed rapidly back towards the control sites. Plant functional composition analysis indicated that the treatments created habitats different both from control sites and target sites. Community-weighted mean Ellenberg indicator values suggested that the observed plant community response was at least partially due to an increase in nitrogen and water availability following disturbance. This study shows that a mild type of disturbance, such as rotavation, may be most successful in promoting specialist species in calcareous sandy grassland, but that further treatments are needed to reduce nutrient availability. We

  3. Soil disturbance as a grassland restoration measure-effects on plant species composition and plant functional traits.

    Science.gov (United States)

    Schnoor, Tim; Bruun, Hans Henrik; Olsson, Pål Axel

    2015-01-01

    Soil disturbance is recognized as an important driver of biodiversity in dry grasslands, and can therefore be implemented as a restoration measure. However, because community re-assembly following disturbance includes stochastic processes, a focus only on species richness or establishment success of particular species will not inform on how plant communities respond ecologically to disturbance. We therefore evaluated vegetation development following disturbance by quantifying species richness, species composition and functional trait composition. Degraded calcareous sandy grassland was subjected to experimental disturbance treatments (ploughing or rotavation), and the vegetation was surveyed during four subsequent years of succession. Treated plots were compared with control plots representing untreated grassland, as well as nearby plots characterized by plant communities representing the restoration target. Species richness and functional diversity both increased in response to soil disturbance, and rotavation, but not ploughing, had a persistent positive effect on the occurrence of specialist species of calcareous sandy grassland. However, no type of soil disturbance caused the plant species composition to develop towards the target vegetation. The disturbance had an immediate and large impact on the vegetation, but the vegetation developed rapidly back towards the control sites. Plant functional composition analysis indicated that the treatments created habitats different both from control sites and target sites. Community-weighted mean Ellenberg indicator values suggested that the observed plant community response was at least partially due to an increase in nitrogen and water availability following disturbance. This study shows that a mild type of disturbance, such as rotavation, may be most successful in promoting specialist species in calcareous sandy grassland, but that further treatments are needed to reduce nutrient availability. We conclude that a

  4. Is our Future Written in the Geological Record of Oceanic Anoxic Events? The Calcareous Nannoplankton Perspective (Invited)

    Science.gov (United States)

    Erba, E.

    2013-12-01

    Cenomanian OAE2 and detected major changes in nannofossil abundance, composition and biomineralization, separating most-, intermediate-, and least-tolerant taxa. The T-OAE, OAE1a and OAE2 share similarities in nannoplankton changes, although some differential response was detected. Nannofossil indices highlight strong variability in climate and fertility during OAEs and point to ocean acidification as central distress to calcifying plankton. In general, calcareous phytoplankton show a major calcification failure of heavily calcified forms, ephemeral coccolith dwarfism and malformation possibly representing most remarkable species-specific adjustments to survive surface water acidity. However, different patterns and degree of calcification reduction, dwarfism and malformation during OAEs suggest unequal volcanic CO2 rates, pulses and amount. The duration of OAEs seems a direct measure of LIP-derived excess CO2, hampering biocalcification while turning the oceans into an immense anoxic pool. Changes in ocean chemistry, structure, and fertility during LIP formation might explain observed tempo and mode of nannoplankton evolution: major origination episodes might result from magmas especially enriched in biogeochemically important elements from the mantle.

  5. 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.

  6. Exploring variations in upper ocean structure for the last 2Ma of the Nansha area by means of calcareous nannofossils

    Institute of Scientific and Technical Information of China (English)

    LlU; Chua; nlian

    2001-01-01

    [1]Molfino, B., Mclntyre, A., Precessional forcing of nutricline dynamics in the Equatorial Atlantic, Science, 1990, 249:766-769.[2]Ahagon, N., Tanaka, Y., Ujiie, H., Florisphaera profunda, a possible nannoplankton indicator of late quaternary changes in seawater turbidity at the northwestern margin of the Pacific, Marine Micropaleontology, 1993, 22: 255-273.[3]Cheng, X., Wang, P, Variations in late Quaternary upper ocean structure of Okinawa Trough: A nannofossil approach,Science in China, Ser. D, 1998, 41(3): 290-296.[4]Okada, H., Matsuoka, M., Lower-photic nannoflora as an indicator of the late Quaternary monsoonal palaeo-record in the tropical Indian Ocean, in Micro-fossils and Oceanic Environments (eds. Moguilevsky, A., Whatley, R.), University of Wales, Aberystwyth Press, 1996, 231-245.[5]Beaufort, L., Lancelot, Y., Camberlin, P. et al., Insolation cycles as a major control of equatorial Indian Ocean primary production, Science, 1997, 278: 1451-1454.[6]Bassinot, F. C., Beaufort, L., Vincent, E. et al., Changes in the Dynamics of western Equatorial Atlantic surface current sand biogenic productivity at the “Mid-Pleistocene Revolution“ (930 ka), in Proceedings of the Ocean Drilling Program,Scientific Results (eds. Shackleton, N. J., Curry, W. B., Richter, C.), 1997, 154: 269-284.[7]Castradori, D., Calcareous nannofossils and the origin of eastern Mediterranean sapropels, Paleoceanography, 1993, 8(4):459-471.[8]Baumann, K. H., Cepek, M., Kinkel, H., Coccolithophores as indicators of ocean water masses, surface-water temperature,and paleoproductivity Examples from the South Atlantic, in Use of Proxies in Paleoceanography: Examples from the South Atlantic (eds. Fischer, G., Wefer, G.), Heidelberg: Springer-Verlag, 1999, 111-144.[9]Kinkel, H., Baumann, K. H., Cepek, M., Coccolithophores in the equatorial Atlantic Ocean: Response to seasonal and Late Quaternary surface water variability, Marine Micropaleontology, 2000, 39

  7. Early Forest Soils and Their Role in Devonian Global Change

    Science.gov (United States)

    Retallack

    1997-04-25

    A paleosol in the Middle Devonian Aztec Siltstone of Victoria Land, Antarctica, is the most ancient known soil of well-drained forest ecosystems. Clay enrichment and chemical weathering of subsurface horizons in this and other Devonian forested paleosols culminate a long-term increase initiated during the Silurian. From Silurian into Devonian time, red clayey calcareous paleosols show a greater volume of roots and a concomitant decline in the density of animal burrows. These trends parallel the decline in atmospheric carbon dioxide determined from isotopic records of pedogenic carbonate in these same paleosols. The drawdown of carbon dioxide began well before the Devonian appearance of coals, large logs, and diverse terrestrial plants and animals, and it did not correlate with temporal variation in volcanic or metamorphic activity. The early Paleozoic greenhouse may have been curbed by the evolution of rhizospheres with an increased ratio of primary to secondary production and by more effective silicate weathering during Silurian time.

  8. Soil friability

    DEFF Research Database (Denmark)

    Munkholm, Lars Juhl

    2011-01-01

    This review gathers and synthesizes literature on soil friability produced during the last three decades. Soil friability is of vital importance for crop production and the impact of crop production on the environment. A friable soil is characterized by an ease of fragmentation of undesirably large...... aggregates/clods and a difficulty in fragmentation of minor aggregates into undesirable small elements. Soil friability has been assessed using qualitative field methods as well as quantitative field and laboratory methods at different scales of observation. The qualitative field methods are broadly used...... by scientists, advisors and farmers, whereas the quantitative laboratory methods demand specialized skills and more or less sophisticated equipment. Most methods address only one aspect of soil friability, i.e. either the strength of unconfined soil or the fragment size distribution after applying a stress. All...

  9. Soil proteomics

    DEFF Research Database (Denmark)

    Oonk, S.; Cappellini, Enrico; Collins, M.J.

    2012-01-01

    In this work, two sets of experiments were carried out to assess the potential of soil proteomics for archaeological site interpretation. First, we examined the effects of various protein isolation reagents and soil constituents on peptide mass fingerprinting (PMF) of soil-like materials spiked...... with bovine serum albumin (BSA). In a subsequent case study, we assessed the relative age of soils from an ancient clay floor of a Roman farmhouse using amino acid racemization and then applied MALDI-TOF-MS-MS to detect and identify biomarkers for human occupation. The results from the first experiments......) are more susceptible to isolation than other regions and this suggest that soil proteins can be only partly isolated. Soil-protein interactions were also found to inhibit tryptic cleavage of BSA, resulting in an enhanced specificity of BSA peptides. Our results further stress the importance of multiple...

  10. Mercury in soils and microbial biomass of the South Kirgizstan subregion of the biosphere

    Science.gov (United States)

    Vadim, Ermakov; Valentina, Danilova; Ul'yana, Gulyaeva

    2016-04-01

    The purpose of this investigation was to clear up the role of soil microflora in the mercury concentration by microorganisms as they are related to a problem of the soil remediation. To complete the tasks as assigned, 150 samples of both various soils formed over the ore bodies outside the ore occurrence zones and waste dumps have been taken in the areas of South Kirgizstan Some 45 soil samples (horizon A, 0-20 cm) and dumps were used for microbiological analyses [1, 2]. The soil cover as seen in the work areas is represented by Haplic Calcisols (gray) soils. All the soils are generally calcareous, in some cases salted, and have various compositions. To grow the microbial biomass in order to determine mercury content levels in there, some soil media characterized by natural concentrations, ratios and forms of the compounds of these metals were used The results showed that the mercury concentrations in soils of the sampling area varied from 0.028 to 357.3 mg/kg. The highest metal content indices (up to 357.3 mg/kg) were found for soils formed over ores, and waste dumps. The lowest mercury content (0.028 to 0.066 mg/kg) was found for soils of the control area. The data on mercury and/or antimony accumulation by the biomass of soil microorganisms grown in soil media are represented. The soil samples having various mercury levels were collected in the South Kirgizstan subregion of the biosphere. It was established that the accumulation of the metals by soil microflora depends on their content in the soil, the microorganism growth is strongly inhibited at mercury concentration of 300 mg/kg in soil. A direct and reliable correlation between the metal content level in soils and their concentration by microorganisms is found. Within the background sites a tendency of increase in mercury extraction from the soil with 1 M HCl solution, in particular from salted soils is observed. In contrast, in the conditions of an excess of mercury content in soils of ore grounds, a weak

  11. (Contaminated soil)

    Energy Technology Data Exchange (ETDEWEB)

    Siegrist, R.L.

    1991-01-08

    The traveler attended the Third International Conference on Contaminated Soil, held in Karlsruhe, Germany. The Conference was a status conference for worldwide research and practice in contaminated soil assessment and environmental restoration, with more than 1500 attendees representing over 26 countries. The traveler made an oral presentation and presented a poster. At the Federal Institute for Water, Soil and Air Hygiene, the traveler met with Dr. Z. Filip, Director and Professor, and Dr. R. Smed-Hildmann, Research Scientist. Detailed discussions were held regarding the results and conclusions of a collaborative experiment concerning humic substance formation in waste-amended soils.

  12. Exploring functional relationships between post-fire soil water repellency, soil structure and physico-chemical properties

    Science.gov (United States)

    Quarfeld, Jamie; Brook, Anna; Keestra, Saskia; Wittenberg, Lea

    2016-04-01

    Soil water repellency (WR) and aggregate stability (AS) are two soil properties that are typically modified after burning and impose significant influence on subsequent hydrological and geomorphological dynamics. The response of AS and soil WR to fire depends upon how fire has influenced other key soil properties (e.g. soil OM, mineralogy). Meanwhile, routine thinning of trees and woody vegetation may alter soil properties (e.g. structure and porosity, wettability) by use of heavy machinery and species selection. The study area is situated along a north-facing slope of Mount Carmel national park (Israel). The selected sites are presented as a continuum of management intensity and fire histories. To date, the natural baseline of soil WR has yet to be thoroughly assessed and must be investigated alongside associated soil aggregating parameters in order to understand its overall impact. This study examines (i) the natural baseline of soil WR and physical properties compared to those of disturbed sites in the immediate (controlled burn) and long-term (10-years), and (ii) the interactions of soil properties with different control factors (management, surface cover, seasonal-temporal, burn temperature, soil organic carbon (OC) and mineralogy) in Mediterranean calcareous soils. Analysis of surface soil samples before and after destruction of WR by heating (200-600°C) was implemented using a combination of traditional methods and infrared (IR) spectroscopy. Management and surface cover type conditioned the wettability, soil structure and porosity of soils in the field, although this largely did not affect the heat-induced changes observed in the lab. A positive correlation was observed along an increasing temperature gradient, with relative maxima of MWD and BD reached by most soils at the threshold of 400-500°C. Preliminary analyses of soil OC (MIR) and mineralogical composition (VIS-NIR) support existing research regarding: (i) the importance of soil OC quality and

  13. Plant-microorganism-soil interactions influence the Fe availability in the rhizosphere of cucumber plants.

    Science.gov (United States)

    Pii, Youry; Penn, Alexander; Terzano, Roberto; Crecchio, Carmine; Mimmo, Tanja; Cesco, Stefano

    2015-02-01

    Iron (Fe) is a very important element for plants, since it is involved in many biochemical processes and, often, for the low solubility of the natural Fe sources in soil, plants suffer from Fe - deficiency, especially when grown on calcareous soils. Among the numerous plant growth-promoting rhizobacteria (PGPR) that colonize the rhizosphere of agronomically important crops, Azospirillum brasilense has been shown to exert strong stimulating activities on plants, by inducing alterations of the root architecture and an improvement of mineral nutrition, which could result from an enhancement of ion uptake mechanisms as well as by increased bioavailability of nutrients. Some studies have also established that A. brasilense can act as biocontrol agent, by preventing the growth and/or virulence of phytopathogens, most likely through the production of microbial siderophores that sequester Fe from the soil. Despite microbial siderophores complexed with Fe could be an easily accessible Fe source for plants, the possible involvement of A. brasilense in improving Fe nutrition in plants suffering from the micronutrient deficiency has not been investigated yet. Within the present research, the characterization of the physiological and biochemical effects induced by Fe starvation and PGPR inoculation in cucumber plants (Cucumis sativus L. cv. Chinese Long) was carried out. The analyses of root exudates released by hydroponically grown plants highlighted that cucumber plants respond differently depending on the nutritional status. In addition, following the cultivation period on calcareous soil, also the root exudates found in the extracts suggested a peculiar behaviour of plants as a function of the treatment. Interestingly, the presence of the inoculum in soil allowed a faster recovery of cucumber plants from Fe-deficiency symptoms, i.e. increase in the chlorophyll content, in the biomass and in the Fe content of leaves. These observations might suggest a feasible application of

  14. Effects of anthropogenic particles on the chemical and geophysical properties of urban soils, Detroit, Michigan

    Science.gov (United States)

    Orlicki, Katharine M.

    There is a great need in many cities for a better quality of urban soil maps. This is due to the increasing interest in repurposing vacant land for urban redevelopment, agriculture, and green infrastructure. Mapping vacant urban land in Detroit can be very difficult because anthropogenic soils were often highly variable and frequently contained demolition debris (such as brick), making it difficult to use a hand auger. This study was undertaken in Detroit, MI to create a more efficient way to map urban soils based on their geophysical and chemical properties. This will make the mapping process faster, less labor intensive, and therefore more cost effective. Optical and chemical criteria for the identification and classification of microartifacts (MAs) were made from a set of reference artifacts of a known origin. These MAs were then observed and tested in urban topsoil samples from sites in Detroit, Michigan that represent three different land use types (residential demolition, fly ash-impacted, and industrial). Optical analyses, SEM, EDAX, and XRD showed that reference MAs may be classified into five basic compositional types (carbonaceous, calcareous, siliceous, ferruginous and miscellaneous). Reference MAs were generally distinguishable using optical microscopy by color, luster, fracture and microtexture. MAs that were more difficult to classify were further differentiable when using SEM, EDAX, and XRD. MAs were found in all of the anthropogenic soils studied, but were highly variable. All three study sites had concentrations coal-related wastes were the most common types of MAs observed and often included coal, ash (microspheres, microagglomerate), cinders, and burnt shale. MAs derived from waste building materials such as brick, mortar, and glass, were typically found on residential demolition sites. Manufacturing waste MAs, which included iron-making slag and coked coal were commonly observed on industrial sites. Fly ash-impacted sites were composed of only

  15. Iron deficiency chlorosis in plants as related to Fe sources in soil

    Science.gov (United States)

    Díaz, I.; Delgado, A.; de Santiago, A.; del Campillo, M. C.; Torrent, J.

    2012-04-01

    Iron deficiency chlorosis (IDC) is a relevant agricultural problem in many areas of the World where calcareous soils are dominant. Although this problem has been traditionally ascribed to the pH-buffering effect of soil carbonates, the content and type of Fe oxides in soil contribute to explain Fe uptake by plants and the incidence of this problem. During the last two decades, it has been demonstrated Fe extraction with oxalate, related to the content of poorly crystalline Fe oxides, was well-correlated with the chlorophyll content of plants and thus with the incidence of IDC. This reveals the contribution of poorly crystalline Fe oxides in soil to Fe availability to plants in calcareous soils, previously shown in microcosm experiments using ferrihydrite as Fe source in the growing media. In order to supply additional information about the contribution of Fe sources in soil to explain the incidence of IDC and to perform accurate methods to predict it, a set of experiments involving different methods to extract soil Fe and plant cultivation in pots to correlate amounts of extracted Fe with the chlorophyll content of plants (measured using the SPAD chlorophyll meter) were performed. The first experiment involved 21 soils and white lupin cultivation, sequential Fe extraction in soil to study Fe forms, and single extractions (DTPA, rapid oxalate and non-buffered hydroxylamine). After that, a set of experiments in pot involving growing of grapevine rootstocks, chickpea, and sunflower were performed, although in this case only single extractions in soil were done. The Fe fraction more closely related to chlorophyll content in plants (r = 0.5, p citrate + ascorbate (CA) extraction, which was the fraction that releases most of the Fe related to poorly crystalline Fe oxides, thus revealing the key role of these compounds in Fe supply to plants. Fe extracted with CA was more correlated with chlorophyll content in plants that oxalate extractable Fe, probably due to a more

  16. Roles of calcareous nannofossil in petroleum exploration. Its usefulness for biostratigraphy, sequence stratigraphy and paleoceanography; Sekiyu tanko ni okeru sekitanshitsu nanno kaseki no yakuwari. Sono seiso jogaku, sequence so jogaku oyobi kokaiyogakuteki yukosei

    Energy Technology Data Exchange (ETDEWEB)

    Hiramatsu, C. [Japan Petroleum Exploration Corp., Musashino, Tokyo (Japan)

    1998-05-01

    Conventionally, stratigraphy of oil field area of East-northern Japan Sea side was decided and used by foraminifer fossils. Foraminifer fossils analysis has various types of benefits not only from the aspect of rich in data, easy available of data at the exploration site, promptness, formation sequence decision but also from the point of view of wider application area such as estimation of paleo-environment using bottom species and so forth, and even at present, it covers the most important position in the fine fossil analysis of well samples. Research of calcareous nannofossil of East-northern coast region of the Japan Sea has been promoted rapidly since the beginning of 1980`s, and its effectiveness for the detail determination of stratigraphy age has been stressed. According to this research findings, quaternary section will be possible with contrast of about 10,000 order by using calcareous nannofossil base. In this report, simple introduction of the application of calcareous nannofossil stratigraphy to oil exploration in the same region together with the role of calcareous nannofossil in the oil exploration, are described. 29 refs., 8 figs.

  17. Root iron uptake efficiency of Ulmus laevis and U. minor and their distribution in soils of the Iberian Peninsula.

    Science.gov (United States)

    Venturas, Martin; Fernández, Victoria; Nadal, Paloma; Guzmán, Paula; Lucena, Juan J; Gil, Luis

    2014-01-01

    The calcifuge and calcicole character of wild plants has been related to nutrient availability shortages, including iron (Fe)-deficiency. Surprisingly, just a few studies examined the relation between root Fe uptake and plant distribution in different soil types. We assessed the root Fe acquisition efficiency of two Ulmus species with calcareous (Ulmus minor) and siliceous (U. laevis) soil distribution patterns in the Iberian Peninsula. Seedlings of both elm species were grown hydroponically with different Fe concentrations during 6 weeks. Plant physiological responses to Fe-limiting conditions were evaluated as were the ferric reductase activity and proton (H(+)) extrusion capacity of the roots. Iron deprived elm seedlings of both species were stunted and suffered severe Fe-chlorosis symptoms. After Fe re-supply leaf chlorophyll concentrations rose according to species-dependent patterns. While U. minor leaves and seedlings re-greened evenly, U. laevis did so along the nerves of new growing leaves. U. minor had a higher root ferric reductase activity and H(+)-extrusion capability than U. laevis and maintained a better nutrient balance when grown under Fe-limiting conditions. The two elm species were found to have different Fe acquisition efficiencies which may be related to their natural distribution in calcareous and siliceous soils of the Iberian Peninsula.

  18. Root iron uptake efficiency of Ulmus laevis and U. minor and their distribution in soils of the Iberian Peninsula

    Directory of Open Access Journals (Sweden)

    Martin eVenturas

    2014-03-01

    Full Text Available The calcifuge and calcicole character of wild plants has been related to nutrient availability shortages, including iron (Fe-deficiency. Surprisingly, just a few studies examined the relation between root Fe uptake and plant distribution in different soil types. We assessed the root Fe acquisition efficiency of two Ulmus species with calcareous (U. minor and siliceous (U. laevis soil distribution patterns in the Iberian Peninsula. Seedlings of both elm species were grown hydroponically with different Fe concentrations during six weeks. Plant physiological responses to Fe-limiting conditions were evaluated as were the ferric reductase activity and proton (H+ extrusion capacity of the roots. Iron deprived elm seedlings of both species were stunted and suffered severe Fe-chlorosis symptoms. After Fe re-supply leaf chlorophyll concentrations rose according to species-dependent patterns. While U. minor leaves and seedlings re-greened evenly, U. laevis did so along the nerves of new growing leaves. Ulmus minor had a higher root ferric reductase activity and H+-extrusion capability than U. laevis and maintained a better nutrient balance when grown under Fe-limiting conditions. The two elm species were found to have different iron acquisition efficiencies which may be related to their natural distribution in calcareous and siliceous soils of the Iberian Peninsula.

  19. Selective Sorption of Dissolved Organic Carbon Compounds by Temperate Soils

    Energy Technology Data Exchange (ETDEWEB)

    Jagadamma, Sindhu [ORNL; Mayes, Melanie [ORNL; Phillips, Jana Randolph [ORNL

    2012-01-01

    Physico-chemical sorption of dissolved organic carbon (DOC) on soil minerals is one of the major processes of organic carbon (OC) stabilization in soils, especially in deeper layers. The attachment of C on soil solids is related to the reactivity of the soil minerals and the chemistry of the sorbate functional groups, but the sorption studies conducted without controlling microbial activity may overestimate the sorption potential of soil. This study was conducted to examine the sorptive characteristics of a diverse functional groups of simple OC compounds (D-glucose, L-alanine, oxalic acid, salicylic acid, and sinapyl alcohol) on temperate climate soil orders (Mollisols, Ultisols and Alfisols) with and without biological degradative processes. Equilibrium batch experiments were conducted using 0-100 mg C L-1 at a solid-solution ratio of 1:60 for 48 hrs and the sorption parameters were calculated by Langmuir model fitting. The amount of added compounds that remained in the solution phase was detected by high performance liquid chromatography (HPLC) and total organic C (TOC) analysis. Soil sterilization was performed by -irradiation technique and experiments were repeated to determine the contribution of microbial degradation to apparent sorption. Overall, Ultisols did not show a marked preference for apparent sorption of any of the model compounds, as indicated by a narrower range of maximum sorption capacity (Smax) of 173-527 mg kg soil-1 across compounds. Mollisols exhibited a strong preference for apparent sorption of oxalic acid (Smax of 5290 mg kg soil-1) and sinapyl alcohol (Smax of 2031 mg kg soil-1) over the other compounds. The propensity for sorption of oxalic acid is mainly attributed to the precipitation of insoluble Ca-oxalate due to the calcareous nature of most Mollisol subsoils and its preference for sinapyl alcohol could be linked to the polymerization of this lignin monomer on 2:2 mineral dominated soils. The reactivity of Alfisols to DOC was in

  20. Using synthetic models to simulate aging of Cu contamination in soils.

    Science.gov (United States)

    Proffit, S; Marin, B; Cances, B; Ponthieu, M; Sayen, S; Guillon, E

    2015-05-01

    The Bureau Commun de Référence (BCR) sequential extraction scheme and micro-synchrotron-based X-ray fluorescence (μ-SXRF) analysis were used to determine the Cu fractionation in a calcareous vineyard soil and a synthetic soil (mixture of seven constituents: calcite, birnessite, ferrihydrite, goethite, lignocellulosic residue, kaolinite, and quartz) at different Cu contamination rates (190, 1270, and 6350 mg kg(-1) of Cu) and aging times (1, 30, 92, and 181 days). The Cu distribution in the spiked vineyard and synthetic soils was different from the original vineyard one and was influenced by the loading level. The newly added Cu was preferentially present in the acid soluble fraction. Aging of the contaminated vineyard and synthetic soils during 6 months led to the redistribution of Cu from the weakly bound acid soluble fraction to the strongly bound reducible one. The evolution with time could satisfactorily be simulated by the Elovich diffusion model for the synthetic soils. It was less significant as less marked in the contaminated vineyard soil than in the synthetic one, even though the trends observed in both were similar. This study supported the hypothesis that "simple" synthetic models could be used to approach the Cu fractionation and its evolution with time in vineyard soils.

  1. Heavy metal contamination and source in arid agricultural soil in central Gansu Province, China

    Institute of Scientific and Technical Information of China (English)

    LI Yu; GOU Xin; WANG Gang; ZHANG Qiang; SU Qiong; XIAO Guoju

    2008-01-01

    Concentrations of copper (Cu), lead (Pb), chromium (Cr), mercury (Hg), and arsenic (As) were measured in arid agricultural and irrigated agricultural soils collected in Daba Village, Shajiawuan Village, Gangou Village and Sifangwu Village, located in central Gansu Province, China. Concentrations except Hg and Pb were lower than the background values in grey calcareous soil in the selected arid agricultural soils. Pb concentration exceeded the threshold of arid agricultural soils in China by 72. 46%. These results showed that there was indeed serious pollution with Pb, a slight pollution problem for other selected metals in the irrigated agricultural soils in Daba Village. Principal component analysis (PCA) was used to assess the soil data, applying varimax rotation with Kaiser Normalization. The result showed that the irrigated factor, agricultural factor and anthropogenic factor all contributed to the relations between selected chemical properties. The main factor of accumulation of Cu, Pb, Cr, Hg and As was lithological factor in arid agricultural areas. There is a striking dissimilarity of origin of Cu, Pb, Cr, Hg and As in agricultural soil between the irrigate agriculture and arid agriculture.

  2. RELATIONSHIPS BETWEEN SOIL MICROBIAL BIOMASS, AGGREGATE STABILITY AND AGGREGATE ASSOCIATED-C: A MECHANISTIC APPROACH

    Directory of Open Access Journals (Sweden)

    Patrizia Guidi

    2014-01-01

    Full Text Available For the identification of C pools involved in soil aggregation, a physically-based aggregate fractionation was proposed, and  additional pretreatments were used in the measurement of the 1-2 mm aggregate stability in order to elucidate the relevance of the role of soil microorganisms with respect to the different aggregate breakdown mechanisms. The study was carried out on three clay loam Regosols, developed on calcareous shales, known history of organic cultivation.Our results showed that the soil C pool controlling the process of stabilisation of aggregates was related to the microbial community. We identified the resistance to fast wetting as the major mechanism of aggregate stability driven by microorganims. The plausible hypothesis is that organic farming promotes fungi growth, improving water repellency of soil aggregates by fungal hydrophobic substances. By contrast, we failed in the identification of C pools controlling the formation of aggregates, probably because of the disturbance of mechanical tillage which contributes to the breakdown of soil aggregates.The physically-based aggregate fractionation proposed in this study resulted useful in the  mechanistically understanding of the role of microorganisms in soil aggregation and it might be suggested for studying the impact of management on C pools, aggregates properties and their relationships in agricultural soils.

  3. In situ oxidation remediation technologies: kinetic of hydrogen peroxide decomposition on soil organic matter.

    Science.gov (United States)

    Romero, Arturo; Santos, Aurora; Vicente, Fernando; Rodriguez, Sergio; Lafuente, A Lopez

    2009-10-30

    Rates of hydrogen peroxide decomposition were investigated in soils slurries. The interaction soil-hydrogen peroxide was studied using a slurry system at 20 degrees C and pH 7. To determine the role of soil organic matter (SOM) in the decomposition of hydrogen peroxide, several experiments were carried out with two soils with different SOM content (S1=15.1%, S2=10%). The influence of the oxidant dosage ([H2O2](o) from 10 to 30 g L(-1) and soil weight to liquid phase volume ratio=500 g L(-1)) was investigated using the two calcareous loamy sand soil samples. The results showed a rate dependency on both SOM and hydrogen peroxide concentration being the H2O2 decomposition rate over soil surface described by a second-order kinetic expression r(H2O2) = -dn(H2O2) / W(SOM) dt = kC(H2O2) C(SOM). Thermogravimetric analysis (TGA) was used to evaluate the effect caused by the application of this oxidant on the SOM content. It was found a slightly increase of SOM content after treatment with hydrogen peroxide, probably due to the incorporation of oxygen from the oxidant (hydrogen peroxide).

  4. Agricultural use of soil, consequences in soil organic matter and hydraulic conductivity compared with natural vegetation in central Spain

    Science.gov (United States)

    Vega, Verónica; Carral, Pilar; Alvarez, Ana Maria; Marques, Maria Jose

    2014-05-01

    When ecosystems are under pressure due to high temperatures and water scarcity, the use of land for agriculture can be a handicap for soil and water conservation. The interactions between plants and soils are site-specific. This study provides information about the influence of the preence vs. The absence of vegetation on soil in a semi-arid area of the sout-east of Madrid (Spain, in the Tagus River basin. In this area soil materials are developed over a calcareous-evaporitic lithology. Soils can be classified as Calcisols, having horizons of accumulation with powdered limestone and irregular nodules of calcium carbonate. They can be defined as Haplic Cambisols and Leptic Calcisols (WRB 2006-FAO). The area is mainly used for rainfed agriculture, olive groves, vineyards and cereals. There are some patches of bushes (Quercus sp.) and grasses (Stipa tenacissima L.) although only found on the top of the hills. This study analyses the differences found in soils having three different covers: Quercus coccifera, Stipa tenacissima and lack of vegetation. This last condition was found in the areas between cultivated olive trees. Soil organic matter, porosity and hydraulic conductivity are key properties of soil to understand its ability to adapt to climate or land use changes. In order to measure the influence of different soil covers, four replicates of soil were sampled in each condition at two soil depth, (0-10 cm and 10-20 cm). Hydraulic conductivity was measured in each soil condition and replicate using a Mini-disk® infiltrometer. There were no differences between the two depths sampled. Similarly, there were no changes in electric conductivity (average 0.1±0.03 dS m-1); pH (8.7±0.2) or calcium carbonate content (43±20 %). Nevertheless, significant differences (p>0.001) were found in soil organic matter. The maximum was found in soils under Quercus (4.7±0.5 %), followed by Stipa (2.2±1.1 %). The soil without vegetation in the areas between olive trees had only 0

  5. Green manure addition to soil increases grain zinc concentration in bread wheat.

    Directory of Open Access Journals (Sweden)

    Forough Aghili

    Full Text Available Zinc (Zn deficiency is a major problem for many people living on wheat-based diets. Here, we explored whether addition of green manure of red clover and sunflower to a calcareous soil or inoculating a non-indigenous arbuscular mycorrhizal fungal (AMF strain may increase grain Zn concentration in bread wheat. For this purpose we performed a multifactorial pot experiment, in which the effects of two green manures (red clover, sunflower, ZnSO4 application, soil γ-irradiation (elimination of naturally occurring AMF, and AMF inoculation were tested. Both green manures were labeled with 65Zn radiotracer to record the Zn recoveries in the aboveground plant biomass. Application of ZnSO4 fertilizer increased grain Zn concentration from 20 to 39 mg Zn kg-1 and sole addition of green manure of sunflower to soil raised grain Zn concentration to 31 mg Zn kg-1. Adding the two together to soil increased grain Zn concentration even further to 54 mg Zn kg-1. Mixing green manure of sunflower to soil mobilized additional 48 µg Zn (kg soil-1 for transfer to the aboveground plant biomass, compared to the total of 132 µg Zn (kg soil-1 taken up from plain soil when neither green manure nor ZnSO4 were applied. Green manure amendments to soil also raised the DTPA-extractable Zn in soil. Inoculating a non-indigenous AMF did not increase plant Zn uptake. The study thus showed that organic matter amendments to soil can contribute to a better utilization of naturally stocked soil micronutrients, and thereby reduce any need for major external inputs.

  6. Soil Solution

    NARCIS (Netherlands)

    Sonneveld, C.; Voogt, W.

    2009-01-01

    The characteristics of the soil solution in the root environment in the greenhouse industry differ much from those for field grown crops. This is caused firstly by the growing conditions in the greenhouse, which strongly differ from those in the field and secondly the function attributed to the soil

  7. Linking soil biodiversity and agricultural soil management

    NARCIS (Netherlands)

    Thiele-Bruhn, S.; Bloem, J.; Vries, de F.T.; Kalbitz, K.; Wagg, C.

    2012-01-01

    Soil biodiversity vastly exceeds aboveground biodiversity, and is prerequisite for ecosystem stability and services. This review presents recent findings in soil biodiversity research focused on interrelations with agricultural soil management. Richness and community structure of soil biota depend o

  8. Soil investigation in cities of West Hungary

    Science.gov (United States)

    Bidló, A.; Szżcs, P.; Horváth, A.; Kámán, O.; Németh, E.

    2012-04-01

    are determined fundamentally by the parent material, but in the city center the acidity of soils were alkaline (by the greatest number of point). The cause of this is the calcareous deposited debris. The particle size distribution of soils showed various appearances, but there was not possible to discover the tendencies. In most cases there was a high value of organic substance in the downtown area, partly due to frequent grass fertilisation and soil spreading. We detected the amount of easily solvent nutrients and we established, that the value of nutriment element did not show significant differences in connection with usage. Our work will be continued and we are currently measuring heavy metal content of soil, and searching for the connection between the urban area and condition of soils. These investigations have been carried out with the sponsorships of TÁMOP-4.2.1.B-09/1/KONV-2010-0006 and TÁMOP-4.2.2.B-10/1-2010-0018.

  9. 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.

  10. The Jurassic/Cretaceous boundary in the Apulco area by means of calpionellids and calcareous dinoflagellates: An alternative to the classical Mazatepec section in eastern Mexico

    Science.gov (United States)

    López-Martínez, Rafael; Barragán, Ricardo; Reháková, Daniela

    2013-11-01

    A detailed bed-by-bed sampling within the Pimienta and the Lower Tamaulipas Formations from a section in the Apulco area (Puebla State, Eastern Mexico), allows the delimitation of the Jurassic/Cretaceous boundary. The Late Tithonian was identified by the presence of calpionellids of the Crassicollaria Zone (Colomi Subzone) and calcareous dinocysts of the Proxima Zone. The Tithonian/Berriasian boundary was placed at the acme of Calpionella alpina (small forms) between samples MZT 45-46. The Berriasian was divided into two main units, namely the Calpionella Zone, further subdivided into the Alpina, Ferasini and Elliptica subzones, and the Calpionellopsis Zone, within which only the Oblonga subzone was identified. The vertical distribution of calpionellids and their assemblages in the biozones of this Mexican section fit those from other Tethyan areas.

  11. Non-monophyly of most supraspecific taxa of calcareous sponges (Porifera, Calcarea) revealed by increased taxon sampling and partitioned Bayesian analysis of ribosomal DNA.

    Science.gov (United States)

    Dohrmann, Martin; Voigt, Oliver; Erpenbeck, Dirk; Wörheide, Gert

    2006-09-01

    Calcareous sponges (Porifera, Calcarea) play an important role for our understanding of early metazoan evolution, since several molecular studies suggested their closer relationship to Eumetazoa than to the other two sponge 'classes,' Demospongiae and Hexactinellida. The division of Calcarea into the subtaxa Calcinea and Calcaronea is well established by now, but their internal relationships remain largely unresolved. Here, we estimate phylogenetic relationships within Calcarea in a Bayesian framework, using full-length 18S and partial 28S ribosomal DNA sequences. Both genes were analyzed separately and in combination and were further partitioned by stem and loop regions, the former being modelled to take non-independence of paired sites into account. By substantially increasing taxon sampling, we show that most of the traditionally recognized supraspecific taxa within Calcinea and Calcaronea are not monophyletic, challenging the existing classification system, while monophyly of Calcinea and Calcaronea is again highly supported.

  12. 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".

  13. The creation of a digital soil map for Cyprus using decision-tree classification techniques

    Science.gov (United States)

    Camera, Corrado; Zomeni, Zomenia; Bruggeman, Adriana; Noller, Joy; Zissimos, Andreas

    2014-05-01

    classes with a success percentage included between 88% (calcaric fluvic Cambisols and vertic Cambisols) and 96% (skeletric calcaric Regosols and calcaric lithic Leptosols). In a parallel study, characteristic profiles are assigned to every soil class. The soil classes will be field checked with mapped and unmapped areas including points with new soil properties. This study is part of the AGWATER project (AEIFORIA/GEORGO/0311(BIE)/06), co-financed by the European Regional Development Fund and the Republic of Cyprus through the Research Promotion Foundation. Cohen, D.R., Rutherford, N.F., Morisseau, E., and Zissimos, A.M.: Geochemical Atlas of Cyprus. Sydney: UNSW Press; 2011. McBratney, A.B., Mendonça Santos, M.L., and Minasny, B.: On digital soil mapping. Geoderma 117, 3-52, 2003 Noller, J.: The Geomorphology of Cyprus. Cyprus Geological Survey, Open File Report, 269 p, 2009.

  14. 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.   

  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. Evolution, Abundance and Biocalcification of Calcareous Nannoplankton During the Aptian (Early Cretaceous): Causes and Consequences for C Isotopic Anomalies, Climate Changes and the Carbon Cycle.

    Science.gov (United States)

    Erba, E.

    2005-12-01

    The mid Cretaceous is marked by extreme greenhouse conditions, coeval with emplacement of large igneous provinces, C isotopic anomalies, major changes in structure and composition of the oceans, and accelerated rates in the evolutionary history of calcareous plankton. The Aptian is a crucial interval to decipher links between biotic evolution and environmental pressure: it is appealing for understanding nannofloral biocalcification and feedbacks in the carbonate system and in the global carbon cycle. Ontong Java, Manihiki and Kerguelen Plateaus formed in the Aptian affecting the ocean-atmosphere system with excess CO2, changes in Ca2+ and Mg2+ concentrations, and varying nutrient cycling. Two large C isotopic anomalies are associated with episodes of prolonged high primary productivity, changes in alkality, global warming and cooling, anoxia, speciations and extinctions in planktonic communities. Nannofossil diversity, abundance and biocalcification are quantified in continuous, complete, pelagic sections to derive biosphere-geosphere interactions at short and long time scales. The early Aptian C isotopic anomaly interrupts a speciation episode in calcareous nannoplankton paralleled by a drastic reduction in nannofossil paleofluxes culminating in the nannoconid crisis preceding the Oceanic Anoxic Event 1a and the negative C isotopic spike linked to clathrate melting presumably triggered by the thermal maximum at the onset of the mid Cretaceous greenhouse climate. No extinctions are recorded. In the early late Aptian resumption of nannoconid production and appearance of several taxa are coeval with a return to normal C isotopic values. The occurrence of calpionellids and diversified planktonic foraminifers indicate successful biocalcification and restoration of the thermocline. In the late Aptian a drop in nannofossil abundance and accelerated extinction rates are associated with another C isotopic excursion under cool conditions possibly due to a prolonged volcanic

  17. Changes in soil properties and soil cover structure due to intensive erosion and accumulation processes in loess soils

    Science.gov (United States)

    Zadorova, Tereza; Penizek, Vit; Jaksik, Ondrej; Kodesova, Radka; Jirku, Veronika; Fer, Miroslav

    2010-05-01

    Intensive water and tillage erosion and consequent accumulation are the most important processes affecting the agroecosystems in loess regions and changing soil properties, e.g. organic carbon content, carbonate content or structure stability, and general distribution of soil units in the landscape. South Moravian loess belt, formerly covered mostly by Haplic Chernozem, is now formed by a highly diversified soil mosaic. At a morphologically heterogenous study plot (6 ha), a study on relationship between soil properties and terrain characteristics was held. DTM analysis, detailed terrain survey and laboratory analysis were the main methods adopted in the study. Three main soil units were identified: Haplic Chernozem, calcareous Regosol and Colluvial soil. The distribution of each soil unit correlates with different terrain attributes. Regosols are significatly connected to the steep slope, while their correlation with the curvature or hydrological indexes is lower. On the contrary, the Colluvial soils distribution depends mainly on values of curvature and topographical wetness index and is independent on the slope. Chernozem is related to a specific terrain position more than to any of the terrain attributes. Soil depth and humus horizon thickness vary extremelly - from 0.2 m at the erosionally exposed slopes to more than 2.5 m at the concave parts and the toeslope. Soil depth is significantly correlated with all of the tested terrain attributes except of the slope - the strongest correlation was proved in case of mean curvature, topographical wetness index and catchment area. Different degree of changes in particular soil properties results from the specificity of both erosion process and parent material character. Organic carbon content in the topsoil varies significantly. Humus is practically absent in the steepest parts of the slope where the loess is exposed. High amounts of Corg were identified in the undisturbed A horizons of the Chernozem unit. In the

  18. Study of hydro-saline characteristics of soils a palm grove in basin of Ouargla (Northern Algerian Sahara)

    Science.gov (United States)

    Rezagui, D.; Bouhoun, M. Daddi; Boutoutaou, D.; Djaghoubi, A.

    2016-07-01

    Saharan soils are often faced with several problems of development, taking account the hydro-edaphic constraints, mainly of hydric types by water table, mechanical by gypso-calcareous crusts and saline by irrigation waters and upwelling of water table. Our work consists in doing a soil characterization of a palm grove in Ouargla in order to study the constraints hydro-halomorphes. The results show that irrigation water by two plies of Senonian and Mioplcène had a high salinity with a value of 2.83 and 5.10 dS.m-1 respectively. The conduct of irrigation is traditional random of submersion type. The palm grove has a poor drainage with a level of water table 156.67±15.71 cm and salinity of 31.37±34.04 dS.m-1. The drains are open type and their maintenance is not regular. This situation of management of irrigation-drainage promotes the upwelling of water table and the waterlogging in soils. The study of soil profiles shows the existence of mechanical obstruction of gypso-calcareous crusts which limit the entrenchment of the date palms and the leaching of salts. Soil salinity is excessive in profiles with a range of 8.98 ± 4.58 dS.m-1. This accumulation of salts is due to the dynamic ascending and descending of salts respectively under the effect of upwelling of water table and leaching by irrigation. The salinization, the upwelling of water table and the presence of gypso-calcareous crusts recorded in Ouargla testify to a degradation hydro-halomorphe and mechanic of soil which constitute the major constraints in the management of system irrigation-drainage and sustainable agricultural development of the palm groves of the basin of Ouargla. Some hydro-agricultural planning are necessary to apply in the oasis to improve the hydro-mechanical properties of soils in order to reduce their degradation.

  19. Cadmium phytoavailability to rice (Oryza sativa L.) grown in representative Chinese soils. A model to improve soil environmental quality guidelines for food safety.

    Science.gov (United States)

    Rafiq, Muhammad T; Aziz, Rukhsanda; Yang, Xiaoe; Xiao, Wendan; Rafiq, Muhammad K; Ali, Basharat; Li, Tingqiang

    2014-05-01

    Food chain contamination by cadmium (Cd) is globally a serious health concern resulting in chronic abnormalities. Rice is a major staple food of the majority world population, therefore, it is imperative to understand the relationship between the bioavailability of Cd in soils and its accumulation in rice grain. Objectives of this study were to establish environment quality standards for seven different textured soils based on human dietary toxicity, total Cd content in soils and bioavailable portion of Cd in soil. Cadmium concentrations in polished rice grain were best related to total Cd content in Mollisols and Udic Ferrisols with threshold levels of 0.77 and 0.32mgkg(-1), respectively. Contrastingly, Mehlich-3-extractable Cd thresholds were more suitable for Calcaric Regosols, Stagnic Anthrosols, Ustic Cambosols, Typic Haplustalfs and Periudic Argosols with thresholds values of 0.36, 0.22, 0.17, 0.08 and 0.03mgkg(-1), respectively. Stepwise multiple regression analysis indicated that phytoavailability of Cd to rice grain was strongly correlated with Mehlich-3-extractable Cd and soil pH. The empirical model developed in this study explains the combined effects of soil properties and extractable soil Cd content on the phytoavailability of Cd to polished rice grain. This study indicates that accumulation of Cd in rice is influenced greatly by soil type, which should be considered in assessment of soil safety for Cd contamination in rice. This investigation concluded that the selection of proper soil type for food crop production can help us to avoid the toxicity of Cd in our daily diet.

  20. Isolation and identification of actinomycetes from a compost-amended soil with potential as biocontrol agents.

    Science.gov (United States)

    Cuesta, Gonzalo; García-de-la-Fuente, Rosana; Abad, Manuel; Fornes, Fernando

    2012-03-01

    The search for new biocontrol strategies to inhibit the growth of phytopathogenic microorganisms has become widely widespread due to environmental concerns. Among actinomycetes, Streptomyces species have been extensively studied since they have been recognized as important sources of antibiotics. Actinomycete strains were isolated from a calcareous soil, 2 two-phase olive mill waste ('alperujo') composts, and the compost-amended soil by using selective media, and they were then co-cultured with 5 phytopathogenic fungi and 1 bacterium to perform an in vitro antagonism assay. Forty-nine actinomycete strains were isolated, 12 of them showing a great antagonistic activity towards the phytopathogenic microorganisms tested. Isolated strains were identified by 16S rDNA sequence analysis and phenotypic procedures. Eleven isolates concerned the genus Streptomyces and 1 actinomycete with chitinolytic activity belonged to the genus Lechevalieria.

  1. Short term recovery of soil biological functions in a new vineyard cultivated in organic farming

    Science.gov (United States)

    Costantini, Edoardo; Agnelli, Alessandro; Fabiani, Arturo; Gagnarli, Elena; Mocali, Stefano; Priori, Simone; Simoni, Sauro; Valboa, Giuseppe

    2014-05-01

    Deep earthwork activities carried out before vineyard plantation completely upset soil profile and characteristics. The resulting soil features are often much more similar to the underlying substratum than original soil profile. The time needed to recover soil functions is ecologically relevant and affects vine phenology and grape yield, particularly in organic viticulture. The general aim of this research work was to investigate the time needed to recover soil functions after the earthworks made before vine plantation. This study compared for a four years period physical and chemical properties, microbial and mesofauna communities, in new and old vineyards, cultivated on the same soil type. The experiment was conducted in a farm of the Chianti Classico district (Central Italy), on hills of high altitude (400-500 m a.s.l.) on clayey-calcareous flysches, with stony and calcareous soils (Haplic Cambisol (Calcaric, Skeletic)). The reference vine cultivar was Sangiovese. The older vineyard was planted in 2000, after slope reshaping by bulldozing and back hoe ploughing down to about 0.8-1.0 m. The new vineyard was planted in 2011 after an equivalent earthwork carried out in the summer of 2009. Both vineyards were organically managed and only compost at the rate of 1,000 kg ha-1 -a was added every year. The new vineyard was periodically cultivated by mechanical tillage, while the older only at alternate rows. Soil samples from the first 15 cm depth were collected in 4 replicates in the younger as well as in the older vineyard during the springtime of 2010-2013; in the older vineyard, two samples were from the periodically cultivated swaths and two under permanent grass cover. Samples were analysed for physical (particle size, field capacity, wilting point), chemical (pH, electrical conductivity, lime, active lime, organic carbon, total nitrogen), microbiological (soil respiration, microbial biomass, DGGE), and mesofauna features (abundance, taxa richness, BSQ index and

  2. Effects of long term raw pig slurry inputs on nutrient and metal contamination of tropical volcanogenic soils, Uvéa Island (South Pacific).

    Science.gov (United States)

    Gunkel-Grillon, P; Roth, E; Laporte-Magoni, C; Le Mestre, M

    2015-11-15

    In small Polynesian islands, family pig breeding is usually conducted without recovery of pig slurry. Raw pig slurry is spread onto the soil without any treatment. So far, most of the studies were carried out in temperate climate and for industrial digested pig slurry applications on agricultural lands. In the present case study, conducted in Uvéa Island, the aim is to determine if long term application of raw pig slurry on tropical soils, naturally rich in heavy metals has a significant influence on elements concentrations and mobility. Two types of tropical soils and two pig breeding systems, pig enclosure on small concrete pens or pig enclosure in large land pens, were investigated. Here we demonstrate that raw pig slurry inputs on soils can lead to an increase of total nitrogen and phosphorus content with high Contamination Factors. The Pollution Load Index values (1.3; 5.3; 2.5; 2.3) were indicative of multi-heavy metals pollution (Fe, Mn, Al, Cu, Zn, Cr and Ni) in mixed calcareous soils of the coastal area and they are exchangeable while they are immobilized or less mobile in inland pure ferralitic soils. For mixed calcareous soils of the coastal area, family pig breeding represents a drainage risk of soluble species (phosphorus, inorganic nitrogen, Fe, Mn, Al, Cu, Zn, Cr and Ni). For inland ferralitic soils, family pig breeding is more compatible with a sustainable management of the environment in Uvéa Island and by extension in volcanic tropical islands with respect to the investigated chemical elements.

  3. Chemical properties of organic soils developed from lacustrine chalk near the lakes Strzeszowskie, Sitno, and Sierakowo (Western Pomerania, north Poland

    Directory of Open Access Journals (Sweden)

    Jarnuszewski Grzegorz

    2015-12-01

    Full Text Available The genesis of organic soils is closely connected with water. The occurrence of carbonate deposits in the central and lower part of organic soil profile points to the link between their genesis and post-glacial lakes. The studies conducted in the years 2009–2012 focused on organic soils near lakes: Strzeszowskie, Sitno (Myśliborskie Lakeland and Sierakowo (Ińskie Lakeland, north Poland. The goal of the present study was to characterize chemical properties of organic soils developed on carbonate deposits. The examined soils belonged to organic muck and sapric peat soils. They contained variable amount of organic matter (32,4–66,6%. The C/N ratio depended on the degree of mineralization. The soils under study, had a high level of available forms of Ca and low level of P, K, Cu, and Zn. Both in surface and subsurface horizons of muck and sapric peat soils the content of exchangeable cations may be ranked as follows: Ca > Mg > K > Na. Basic cations total in organic horizons was distinctly higher than in calcareous sediments. In organic horizons and limnic deposits, the share of exchangeable form of Ca in the sum of basic cations exceeded 95%.

  4. Phytoremediation of Polycyclic Aromatic Hydrocarbons in Soils Artificially Polluted Using Plant-Associated-Endophytic Bacteria and Dactylis glomerata as the Bioremediation Plant.

    Science.gov (United States)

    Gałązka, Ann; Gałązka, Rafał

    2015-01-01

    The reaction of soil microorganisms to the contamination of soil artificially polluted with polycyclic aromatic hydrocarbons (PAHs) was evaluated in pot experiments. The plant used in the tests was cock's foot (Dactylis glomerata). Three different soils artificially contaminated with PAHs were applied in the studies. Three selected PAHs (anthracene, phenanthrene, and pyrene) were used at the doses of 100, 500, and 1000 mg/kg d.m. of soil and diesel fuel at the doses of 100, 500, and 1000 mg/kg d.m. of soil. For evaluation of the synergistic effect of nitrogen fixing bacteria, the following strains were selected: associative Azospirillum spp. and Pseudomonas stutzerii. Additionally, in the bioremediation process, the inoculation of plants with a mixture of the bacterial strains in the amount of 1 ml suspension per 500 g of soil was used. Chamber pot-tests were carried out in controlled conditions during four weeks of plant growth period. The basic physical, microbiological and biochemical properties in contaminated soils were determined. The obtained results showed a statistically important increase in the physical properties of soils polluted with PAHs and diesel fuel compared with the control and also an important decrease in the content of PAHs and heavy metals in soils inoculated with Azospirillum spp. and P. stutzeri after cock's foot grass growth. The bioremediation processes were especially intensive in calcareous rendzina soil artificially polluted with PAHs.

  5. Deposition of heavy metals from particulate settleable matter in soils of an industrialized area

    Science.gov (United States)

    Sanfeliu, Teófilo

    2010-05-01

    metals in calcareous and non-calcareous soils in Spain" Water, Air and Soil Pollution 162:127-142. Pallarés S., Vicente A.B.; Jordán M.M.; Sanfeliu T. (2007) "Study of the levels of concentration of As, Cd and Ni in a ceramic cluster" Water, Air and Soil Pollution 180:51-54.

  6. Mineral materials as feasible amendments to stabilize heavy metals in polluted urban soils

    Institute of Scientific and Technical Information of China (English)

    Mingkui Zhang; Jincheng Pu

    2011-01-01

    Four minerals, agricultural limestone (AL), rock phosphate (RP), palygorskite (PG), and calcium magnesium phosphate (CMP), were evaluated by means of chemical fractions of heavy metals in soils and concentrations of heavy metals in leachates from columns to determine their ability to stabilize heavy metals in polluted urban soils.Two urban softs (calcareous soil and acidic soil) polluted with cadmium, copper, zinc and lead were selected and amended in the laboratory with the mineral materials) for 12 months.Results indicated that application of the mineral materials reduced exchangeable metals in the sequence of Pb, Cd > Cu > Zn.The reduction of exchangeable fraction of heavy metals in the soils amended with different mineral materials followed the sequence of CMP, PG > AL > RP.Reductions of heavy metals leached were based on comparison with cumulative totals of heavy metals eluted through 12 pore volumes from an untreated soil.The reductions of the metals eluted from the calcareous soil amended with the RP, AL, PG and CMP were 1.98%, 38.89%, 64.81% and 75.93% for Cd, 8.51%, 40.42%, 60.64% and 55.32% for Cu, 1.76%, 52.94%, 70.00% and 74.12% for Pb, and 28.42%, 52.74%, 64.38% and 49.66% for Zn.Those from the acidic soil amended with the CMP, PG, AL, and RP were 25.65%, 68.06%, 78.01% and 79.06% for Cd, 26.56%, 49.64%, 43.40% and 34.68% for Cu, 44.44%, 33.32%, 61.11% and 69.44% for Pb, and 18.46%, 43.77%, 41.98% and 40.68% for Zn.The CMP and PG treatments were superior to the AL and RP for stabilizing heavy metals in the polluted urban soils.

  7. Estonian soil classification as a tool for recording information on soil cover and its matching with local site types, plant covers and humus forms classifications

    Science.gov (United States)

    Kõlli, Raimo; Tõnutare, Tõnu; Rannik, Kaire; Krebstein, Kadri

    2015-04-01

    Estonian soil classification (ESC) has been used successfully during more than half of century in soil survey, teaching of soil science, generalization of soil databases, arrangement of soils sustainable management and others. The Estonian normally developed (postlithogenic) mineral soils (form 72.4% from total area) are characterized by mean of genetic-functional schema, where the pedo-ecological position of soils (ie. location among other soils) is given by means of three scalars: (i) 8 stage lithic-genetic scalar (from rendzina to podzols) separates soils each from other by parent material, lithic properties, calcareousness, character of soil processes and others, (ii) 6 stage moisture and aeration conditions scalar (from aridic or well aerated to permanently wet or reductic conditions), and (iii) 2-3 stage soil development scalar, which characterizes the intensity of soil forming processes (accumulation of humus, podzolization). The organic soils pedo-ecological schema, which links with histic postlithogenic soils, is elaborated for characterizing of peatlands superficial mantle (form 23.7% from whole soil cover). The position each peat soil species among others on this organic (peat) soil matrix schema is determined by mean of 3 scalars: (i) peat thickness, (ii) type of paludification or peat forming peculiarities, and (iii) stage of peat decomposition or peat type. On the matrix of abnormally developed (synlithogenic) soils (all together 3.9%) the soil species are positioned (i) by proceeding in actual time geological processes as erosion, fluvial processes (at vicinity of rivers, lakes or sea) or transforming by anthropogenic and technological processes, and (ii) by 7 stage moisture conditions (from aridic to subaqual) of soils. The most important functions of soil cover are: (i) being a suitable environment for plant productivity; (ii) forming adequate conditions for decomposition, transformation and conversion of falling litter (characterized by humus

  8. Spatial variability of cv Tempranillo phenology within the Ribera del Duero DO (Spain) related to soil type and plot characteristics

    Science.gov (United States)

    Ramos, Maria C.; Jones, Gregory V.; Yuste, Jesús

    2014-05-01

    Vineyards in the Ribera del Duero area (Spain) date back to the roman time, with significant fluctuations throughout the centuries, reaching consolidation and stable production in the 10th and 11th centuries. The present Ribera del Duero Designation of Origen (DO) started in 1980 and has increased from less than 6,000 ha planted to more than 21,000 ha planted by 2010 and becoming one the top regions for wine production in Spain with success in the global wine market. Vineyards of Ribera del Duero are found along 115 km of the Duero River. Within this distance, differences in elevation and topography produce differences in climate, which provide the means by which a zonification for vineyard management can be assessed. In this work, the differences in phenological growth characteristics for the Tempranillo variety were analyzed within the Ribera del Duero DO and related to soil and plot characteristics. Phenology dates, referenced to different Baggiolini classification stages, were evaluated in 20 control plots distributed throughout the Ribera del Duero DO during the period 2004-2012. These years presented different climatic characteristics, which were analyzed from daily temperature and precipitation series recorded from 1980 to 2012 at five stations located along the Duero River. Most vineyards were cultivated under rainfed conditions. In order to evaluate the spatial variability in phenology, climate and soils, the plots were classified using a hierarchical cluster multivariate analysis. Parameters such as the elevation, the distance to river and the soil type were taken into account in the classification. According to the WRB classification (2006) the main soil types in the area are Calcaric Cambisols, Eutric Cambisols, Calcic Luvisol, Calcaric fluvisols, Eutric fluvisols and in less proportion Lithic Leptosols and Calcaric Rogosols. Four different groups were observed, with differences in elevation, distance to the Duero River and the soil type. The

  9. Genesis and characteristics of the soil in A-R stage in forest ecosystems of NP 'Tara'

    Directory of Open Access Journals (Sweden)

    Knežević Milan

    2009-01-01

    Full Text Available Different types of soil in A-R stage formed on limestone and serpentinite in forest ecosystems in NP 'Tara' were researched. Based on the specific effect of limestone on the soil genesis and evolution, two types of calcareous limestone bedrocks were distinguished: dense limestones, and soft, marly limestones. Three subtypes of black earth were studied on dense limestones. They are: organogenic, organo-mineral and brownised soils. One soil type was researched on soft, marly limestones: rendzina, the leached variety. One soil type was researched on serpentinites, within the A-R stage: humus-siliceous soil (ranker, subtype eutric ranker. This paper also presents the evaluation of ecological and productive characteristics of the study soils. If the soil is observed separately, regardless of the tree species growing on it, the soils in A-R stage in NP 'Tara' cannot be evaluated as highly productive. However, in all plant communities on the soils in A-R stage on limestone, the values of average volume, current volume increment, and basal area were high. The unfavourable physical characteristics of the soil in the area of NP 'Tara' are compensated by the effect of humid climate. On the study eutric humus siliceous soils in the area of NP 'Tara', in the natural and artificially established stands of Scots pine and Austrian pine, the ecological and productive value is conditioned by numerous factors and it is mainly limited by unfavourable physical characteristics. Regardless of the unfavourable ecological and productive characteristics of the soil, the natural and artificially established stands of Scots pine and Austrian pine are in the coeno-ecological optimum.

  10. Process and Mechanism for the Development of Physical Crusts in Three Typical Chinese Soils

    Institute of Scientific and Technical Information of China (English)

    BU Chong-Feng; W.J.GALE; CAI Qiang-Guo; WU Shu-Fang

    2013-01-01

    To compare the development of physical crusts in three typical cultivated soils of China,a black soil (Luvic Phaeozem),a loess soil (Haplic Luvisol),and a purple soil (Calcaric Regosol) were packed in splash plates with covered and uncovered treatments,and exposed to simulated rainfall.Meshes covered above the surfaces of half of soil samples to simulate the effects of crop residue on crusting.The results indicated a progressive breakdown of aggregates on the soil surface as rainfall continued.The bulk density and shear strength on the surface of the three soil types increased logarithmically as rainfall duration increased.During the first 30 min of simulated rainfall,the purple soil developed a 7-8 mm thick crust and the loess soil developed a 3-4 mm thick crust.The black soil developed a distinguishable,but still unstable,crust after 80 min of simulated rainfall.Soil organic matter (SOM) content,the mean weight diameter (MWD) of soil aggregates,and soil clay content were negatively correlated with the rate of crust formation,whereas the percentage of aggregate dispersion (PAD),the exchangeable sodium percentage (ESP),and the silt and sand contents were positively correlated with crusting.Mechanical breakdown caused by raindrop impact was the primary mechanism of crust formation in the black soil with more stable aggregates (MWD 25.0 mm,PAD 3.1%) and higher SOM content (42.6 g kg-1).Slaking and mechanical eluviation were the primary mechanisms of crust formation in the purple soil with low clay content (103 g kg-1),cation exchange capacity (CEC,228 mmol kg-1),ESP (0.60%),and SOM (17.2 g kg-1).Mechanical breakdown and slaking were the most important in the loess soil with low CEC (80.6 mmol kg-1),ESP (1.29%),SOM (9.82 g kg-1),and high PAD (71.7%) and MWD (4.6 mm).Simulated residue cover reduced crust formation in black and loess soils,but increased crust formation in purple soil.

  11. Role of phosphogypsum and NPK amendments on the retention or leaching of metals in different soils.

    Science.gov (United States)

    Ammar, Rawaa; Kanbar, Hussein Jaafar; Kazpard, Véronique; Wazne, Mahmoud; El Samrani, Antoine G; Amacha, Nabil; Saad, Zeinab; Chou, Lei

    2016-08-01

    Column leaching tests were conducted to investigate the effects of soil physicochemical characteristics on metal mobility in the subsurface. The metals investigated originated from disposed industrial waste byproducts and from agrochemicals spread over the farmlands. Soil column tests can provide insights into leaching of metals to underlying water compartments. The findings of this study can be used for prevention strategies and for setting risk assessment approaches to land-use and management, and soil and water quality and sustainability. Soils collected from an industrial (IS) watershed and an agricultural (AQ) hydrographic basin were used in soil column leaching experiments. The soil samples were characterized for mineralogy, functional groups, grain size, surface charge, soil type, porosity, and cation exchange capacity (CEC) along with elemental composition. Varying concentrations of phosphogypsum industrial waste or agrochemical (NPK fertilizer) was then added to the surface of the packed columns (n = 28). The columns were subjected to artificial rain over a period of 65 days. Leachates were collected and analyzed for dissolved Na(+), K(+), and Cd(2+) throughout the experimental period, whereas residual Cd content in the subsurface soil was measured at the end of the experiment. Physicochemical characterization indicated that the AQ soil has a higher potential for metal retention due to its fine clay texture, calcareous pH, high organic matter content and CEC. Metal release was more prominent in the IS soil indicating potential contamination of the surrounding soil and water compartments. The higher metal release is attributed to soil physicochemical characteristics. High calcium concentrations of phosphogypsum origin is expected to compete for adsorbed bivalent elements, such as Cd, resulting in their release. The physicochemical characteristics of the receiving media should be taken into consideration when planning land-use in order to achieve

  12. Spatial distribution of soil water repellency in a grassland located in Lithuania

    Science.gov (United States)

    Pereira, Paulo; Novara, Agata

    2014-05-01

    Soil water repellency (SWR) it is recognized to be very heterogeneous in time in space and depends on soil type, climate, land use, vegetation and season (Doerr et al., 2002). It prevents or reduces water infiltration, with important impacts on soil hydrology, influencing the mobilization and transport of substances into the soil profile. The reduced infiltration increases surface runoff and soil erosion. SWR reduce also the seed emergency and plant growth due the reduced amount of water in the root zone. Positive aspects of SWR are the increase of soil aggregate stability, organic carbon sequestration and reduction of water evaporation (Mataix-Solera and Doerr, 2004; Diehl, 2013). SWR depends on the soil aggregate size. In fire affected areas it was founded that SWR was more persistent in small size aggregates (Mataix-Solera and Doerr, 2004; Jordan et al., 2011). However, little information is available about SWR spatial distribution according to soil aggregate size. The aim of this work is study the spatial distribution of SWR in fine earth (Mataix-Solera, J., Nava, A.L., Alanis, N. (2011) Effects of fire severity on water repellency and agregate stability on mexican volcanic soils, Catena, 84, 136-147. Mataix-Solera, J., Doerr, S. (2004) hydrophobicity and agregate stability in calcareous topsoils from fire-affected pine forests in south-easthern Spain, Geoderma, 118, 77-88. Wessel, A.T. (1988) On using the effective contact angle and the water drop penetration time for classification of water repellency in dune soils, Earth Surfaces Process. Landforms, 13, 555-562, 1988.

  13. Compost and vermicompost of olive cake to bioremediate triazines-contaminated soil.

    Science.gov (United States)

    Delgado-Moreno, Laura; Peña, Aránzazu

    2009-02-15

    The use of organic amendments to bioremediate potential organic pollutants of soil and water has become an increasingly relevant issue in the last years. This strategy has been applied to four triazine herbicides in a typical calcareous agricultural soil of the Mediterranean area. The soil was amended with olive cake, compost and vermicompost of olive cake at rates four times higher than the agronomic dose in order to stimulate biodegradation of simazine, terbuthylazine, cyanazine and prometryn, added in a mixture to the soils. Degradation studies were carried out in sterile and microbially active soil to evaluate the effect of the chemical and biological degradation of triazines. The residual herbicide concentrations at the end of the degradation assay showed no significant differences between non amended and amended soil. However, the addition of compost and vermicompost enhanced the biological degradation rate of triazines during the first week of incubation, with half-lives ranging form 5 to 18 days for the amended soils, whilst negligible degradation occurred in non-amended soil during this period. In contrast, olive cake did not significantly modify the degradation of triazines in spite that the addition of this amendment to soil resulted in the highest dehidrogenase activity values. In all the substrates, degradation of cyanazine and prometryn was faster (between 1.5 and two times higher) than those of terbuthylazine and simazine, without significant relationship with sorption parameters. The first order kinetic equation satisfactorily explained the experimental data for all triazines. A biphasic model, such as that proposed by Hoerl, was better to predict the very rapid triazines decay during the first week of incubation in soil amended with compost and vermicompost.

  14. Physiographic soil map delineation for the Nile alluvium and desert outskirts in middle Egypt using remote sensing data of EgyptSat-1

    Directory of Open Access Journals (Sweden)

    A.A. Afify

    2010-12-01

    Full Text Available The objectives of this study are to produce a physiographic soil map with correlated attributes to be a base for extra modifiers within the land information system. This integrated data will serve the purposes of land use planning, precision farming practices and to be applied in other areas using the extrapolation approach. The Satellite data of EgyptSat-1 were projected on an area of Middle Egypt that represents unique physiographic features over portions of Beni Suef, El Fayoum, Helwan, and October Provinces. The spectral signatures of the land patterns were delineated by the visual interpretation using the physiographic approach, while soil taxa were categorized according to the key of Soil Taxonomy (USDA, 2010, resulting in two landscape categories. The first category includes older and developed parent materials, covering the following units: (a Pediplains of residual soils over limestone parent rock, having soils of Lithic Haplocalcids, loamy skeletal. (b Terraced old alluvial plains represent the formerly deposited alluvium that preceded the recent one of the River Nile alluvium. They includes soils of Typic Calcigypsids, loamy skeletal and old alluvial plain but are currently managed under cultivation. The soils are dominated by Typic Haplocalcids, loamy skeletal. (c Wadis that were shaped by the paleodrainage erosion, are currently subjected to the seasonal flush flooding and are sparsely vegetated including soils of Typic Torrifluvents, lamy skeletal (calcareous; Typic Torriorthents, sandy skeletal, and Typic Torriorthents, sandy. (d Aeolian plain “partly cultivated” includes soils of Typic Torripsamments (calcareous. The second category is a recent River Nile alluvium that formed the following units: (a Terraced recent alluvial plain “cultivated” includes soils of Entic Calcitorrerts, fine and Typic Haplotorrerts fine. (b Recent flat alluvial plain includes soils of Typic Haplotorrerts, fine. (c Meandering belt is aligning

  15. Climate and Biota across the Eocene-Oligocene transition at Site 1090: recent advances on calcareous nannofossils as paleoclimatic and dissolution proxy

    Science.gov (United States)

    Pea, Laura; Fioroni, Chiara; Villa, Giuliana; Persico, Davide; Bohaty, Steve

    2010-05-01

    The Eocene-Oligocene transition represents the biggest biotic turnover in the Cenozoic, involving both terrestrial and marine realms. In this study we present the results obtained by a quantitative analysis of late Eocene-early Oligocene (35.5- 33.1 Ma) calcareous nannofossil assemblages from ODP Site 1090 Hole B (Leg 177). This Hole is located on the southern flank of the Agulhas Ridge on the Subantarctic sector of the Atlantic Ocean (42°54'S), and lies along the boundary between the North Atlantic Deep Water and the Circumpolar Deep Water. Thanks to its position above the Carbonate Compensation Depth (3702 m), the nannofossil assemblage preservation is from poor to good in most of the section, even thought some intervals are barren. A well-preserved magnetostratigraphic signal along all of the section and nannofossil biostratigraphy provided the time framework essential for interpreting the assemblage variations. Within a high resolution biostratigraphic framework and through the comparison with bulk oxygen and carbon isotope datasets we attempt to reconstruct sea surface water temperature and trophic conditions, aimed to a late Eocene - early Oligocene paleoceanographic reconstruction for the South Atlantic. A marked change in the nannofossil assemblages is associated with the Oi-1 event: a nonlinear increase of cool-water taxa gives evidence as the evolution of this climatic event is more complex than previously estimated by calcareous nannofossils in the Southern Ocean (Villa et al., 2008). In fact cool-water taxa variation trend likely reflects the two distinct shifts (Step 1 and Step) recognised by Coxall et al. (2005) within the oxygen isotope shift .Step 1 falls in the uppermost part of magnetochron C13r, while the end of step 2 correlates with the base of Chron C13n (Channell et al., 2005). Furthermore, changes in nannofossil abundance and preservation suggest CCD depth fluctuations, showing a deepening near the Eocene/Oligocene boundary, as previously

  16. The relative importance of fertilization and soil erosion on C-dynamics in agricultural landscapes of NE Germany

    Science.gov (United States)

    Pohl, Madlen; Hoffmann, Mathias; Hagemann, Ulrike; Jurisch, Nicole; Remus, Rainer; Sommer, Michael; Augustin, Jürgen

    2016-04-01

    The hummocky ground moraine landscape of north-east Germany is characterized by distinct small-scale soil heterogeneity on the one hand, and intensive energy crop cultivation on the other. Both factors are assumed to significantly influence gaseous C exchange, and thus driving the dynamics of soil organic carbon stocks in terrestrial, agricultural ecosystems. However, it is not yet clear to which extent fertilization and soil erosional status influence soil C dynamics and whether one of these factors is more relevant than the other. We present seasonal and dynamic soil C balances of biogas maize for the growing season 2011, recorded at different sites located within the CarboZALF experimental area. The sites differ regarding soils (non-eroded Albic Luvisols (Cutanic), extremely eroded Calcaric Regosol and depositional Endogleyic Colluvic Regosol,) and applied fertilizer (100% mineral N fertilizer, 50% mineral and 50% N organic fertilizer, 100% organic N fertilizer). Fertilization treatments were established on the Albic Luvisol (Cutanic). Net-CO2-exchange (NEE) and ecosystem respiration (Reco) were measured every four weeks using a dynamic flow-through non-steady-state closed manual chamber system. Gap filling was performed based on empirical temperature and PAR dependency functions to derive daily NEE values. At the same time, daily above-ground biomass production (NPP) was estimated based on biomass samples and final harvest, using a sigmoidal growth function. In a next step, dynamic soil C balances were generated as the balance of daily NEE and NPP considering the initial C input due to N fertilizers. The resulted seasonal soil C balances varied from strong C losses at the Endogleyic Colluvic Regosol (602 g C m-2) to C gains at the Calcaric Regosol (-132 g C m-2). In general, soils exerted a stronger impact on seasonal and dynamic C balances compared to differences in applied N fertilizer. There are indications that inter-annual variations in climate conditions

  17. Changes in the dynamics of foliar N metabolites in oak saplings by drought and air warming depend on species and soil type.

    Directory of Open Access Journals (Sweden)

    Bin Hu

    Full Text Available Climate change poses direct or indirect influences on physiological mechanisms in plants. In particular, long living plants like trees have to cope with the predicted climate changes (i.e. drought and air warming during their life span. The present study aimed to quantify the consequences of simulated climate change for foliar N metabolites over a drought-rewetting-drought course. Saplings of three Central European oak species (i.e. Quercus robur, Q. petraea, Q. pubescens were tested on two different soil types (i.e. acidic and calcareous. Consecutive drought periods increased foliar amino acid-N and soluble protein-N concentrations at the expense of structural N in all three oak species. In addition, transient effects on foliar metabolite dynamics were observed over the drought-rewetting-drought course. The lowest levels of foliar soluble protein-N, amino acid-N and potassium cation with a minor response to drought and air warming were found in the oak species originating from the driest/warmest habitat (Q. pubescens compared to Q. robur and Q. petraea. Higher foliar osmolyte-N and potassium under drought and air warming were observed in all oak species when grown on calcareous versus acidic soil. These results indicate that species-specific differences in physiological mechanisms to compensate drought and elevated temperature are modified by soil acidity.

  18. Soil Survey Geographic (SSURGO) - Magnesic Soils

    Data.gov (United States)

    California Department of Resources — Magnesic soils is a subset of the SSURGO dataset containing soil family selected based on the magnesic content and serpentinite parent material. The following soil...

  19. In Vitro Assessment of Cadmium Bioavailability in Chinese Cabbage Grown on Different Soils and Its Toxic Effects on Human Health.

    Science.gov (United States)

    Aziz, Rukhsanda; Rafiq, Muhammad Tariq; He, Zhenli; Liu, Di; Sun, Kewang; Xiaoe, Yang

    2015-01-01

    The minimum concentration of cadmium (Cd), by Chinese cabbage grown on Cd contaminated soils that can initiate toxicity in human liver cells using in vitro digestion coupled with Caco-2/HL-7702 cell models was studied. Cadmium bioaccessibility in the gastric phase for yellow soil (YS) cabbage (40.84%) and calcareous soil (CS) cabbage (21.54%) was significantly higher than small intestinal phase with the corresponding values of 21.2% and 11.11%, respectively. Cadmium bioavailability was higher in YS cabbage (5.27%-14.66%) than in CS cabbage (1.12%-9.64%). Cadmium concentrations (>0.74 μg) transported from YS and CS cabbage were able to induce oxidative (MDA, H2O2) stress by inhibiting antioxidant (SOD, GPx) enzyme activities in human liver cells (HL-7702). Additionally the study revealed that the ingestion of Cd contaminated Chinese cabbage grown in acidic soil (yellow soil) weakened the antioxidant defense system under all levels of contamination (2, 6, and 9 mg·kg(-1)) which ultimately escalated the oxidative stress in liver cells; however, in case of CS cabbage, a marked oxidative stress was observed only at 9 mg kg(-1) Cd level of soil. Therefore, it is necessary to monitor Cd concentrations in leafy vegetables grown on acidic soils to minimize human health risk.

  20. Effects of Soil pH,Texture,Moisture,Organic Matter and Cadmium Content on Cadmium Diffusion Coefficient

    Institute of Scientific and Technical Information of China (English)

    WUQI-TANG; J.L.MOREL; 等

    1994-01-01

    The supply of cadmium from soil to plant roots mainly depends on the diffusion prooess.This work was conducted to study the effects of some soil properties on cadmium diffusion coefficient (D) in soil. Measurements were made using the Shofield and Graham-Bryce's isotopic labelling method.Cadmium diffusion coefficients varied from 10-7to 10-9 cms2-1.Higher values were observed in acid sandy soils and lower values in calcareous clay soils.Liming an acid soil resulted in a substantial decrease of D.Addition of cadmium as nitrate salt generally increased D,while addition of sewage sludge and organic matter resulted in a significant decrease of cadmium diffusion.The rhizospheric activity also induced a moderate reduction in D.The relationships between D(10-9cms2-1)on the on hand and soil pH.moisture(Mc,g kg-1) ,organic matter(OM,g kg-1),clay(Cy,gkg-1)and cadmium content(Cd,mgkg-1) on the other were obtained by the multiple regression:D=182.1-29.91pH+0.210Mc-0.303OM+0.011Cy+1.64Cd(R2=0.859,n=22).

  1. In Vitro Assessment of Cadmium Bioavailability in Chinese Cabbage Grown on Different Soils and Its Toxic Effects on Human Health

    Science.gov (United States)

    Aziz, Rukhsanda; Rafiq, Muhammad Tariq; He, Zhenli; Liu, Di; Sun, Kewang; Xiaoe, Yang

    2015-01-01

    The minimum concentration of cadmium (Cd), by Chinese cabbage grown on Cd contaminated soils that can initiate toxicity in human liver cells using in vitro digestion coupled with Caco-2/HL-7702 cell models was studied. Cadmium bioaccessibility in the gastric phase for yellow soil (YS) cabbage (40.84%) and calcareous soil (CS) cabbage (21.54%) was significantly higher than small intestinal phase with the corresponding values of 21.2% and 11.11%, respectively. Cadmium bioavailability was higher in YS cabbage (5.27%–14.66%) than in CS cabbage (1.12%–9.64%). Cadmium concentrations (>0.74 μg) transported from YS and CS cabbage were able to induce oxidative (MDA, H2O2) stress by inhibiting antioxidant (SOD, GPx) enzyme activities in human liver cells (HL-7702). Additionally the study revealed that the ingestion of Cd contaminated Chinese cabbage grown in acidic soil (yellow soil) weakened the antioxidant defense system under all levels of contamination (2, 6, and 9 mg·kg−1) which ultimately escalated the oxidative stress in liver cells; however, in case of CS cabbage, a marked oxidative stress was observed only at 9 mg kg−1 Cd level of soil. Therefore, it is necessary to monitor Cd concentrations in leafy vegetables grown on acidic soils to minimize human health risk. PMID:26167479

  2. Assessing the Effect of Cement Dust Emission on the Physicochemical Nature of Soil around Messebo area, Tigray, North Ethopia

    Directory of Open Access Journals (Sweden)

    SAMUEL ESTIFANOS

    2012-12-01

    Full Text Available Twenty six soil samples were collected around the vicinity of Messebo cement factory in Mekelle, Ethiopia from 0-5 and 5-15 cm depths and determined their physicochemical properties and heavy metals contents. The results indicated that the soils are calcareous having sandy loam to loamy sand texture. The top and lower parts of the soil are found to be alkaline with mean pH 8.97 and 8.93; EC 223.06 and 88.22 µS/cm respectively. The cation exchange capacity of the top soil (0-5cm range from 9 to 27 mmolc kg-1, while the exchangeable Ca and Mg range from 6.4 to 16 and 2.2 to 5.0 mmolc kg- 1 respectively. The average Ca concentration values for the upper and lower soil depths are 418ppm and 404.36ppm respectively. Water extractable analysis results verify the degree of leaching of the metals from anthropogenic source. Geoaccumulation index confirms that the two soil depths are similarly categorized as very heavily contaminated with (As, Cr, Co and Ni and moderately to heavily contaminated with (Cu, Pb and Mo whereas the top part is moderately contaminated with Zn. Based on Enrichment Factor (EF, both soil depths have moderate enrichment with Pb ( 2 EF >20, very high enrichment with Cr (2040. The severe contamination is evident to the east western direction towards which the wind blow predominantly.

  3. Effect of a cation exchange resin on the uptake of heavy metals by grapevines and other cultivated plants grown in contaminated soils

    Energy Technology Data Exchange (ETDEWEB)

    Mohr, H.D.

    1982-12-01

    The effect of a cation exchange resin on the growth and heavy metal content of grapevine, sun flower, cress, wheat and Italian rye-grass was investigated in potted vineyard soil, contaminated by Cu-containing (total Cu content of the soil: 628 ppm), or a soil contaminated artificially with 20 ppm Cd. Roots of cress seedlings grown in a vineyard soil mixed with a cation exchange resin were 2.2 times longer than in the untreated soil. Rye-grass was not injured, whereas grapevine, sun flower and wheat showed varying degrees of growth reduction, chlorosis and necrosis when grown in untreated vineyard soil. However, wheat and sunflower grown in vineyard soil containing a cation exchange resin showed no injury and grapevines exhibited markedly reduced symptoms. The Zn, Cu and Cd content of the plants decreased considerably, whereas their Fe and Mn content was not influenced. Grapevine, grown in a calcareous soil contaminated with 20 ppm Cd, contained 447 ppm Cd in the roots and 0,20 ppm Cd in the leaves. The Cd content of the roots declined to 113 ppm, that of the leaves to 0,15 ppm when grown in the contaminated soil containing a cation exchanger.

  4. Short-term effect of vermicompost application on biological properties of an alkaline soil with high lime content from Mediterranean region of Turkey.

    Science.gov (United States)

    Uz, Ilker; Tavali, Ismail Emrah

    2014-01-01

    This study was conducted to investigate direct short-term impact of vermicompost on some soil biological properties by monitoring changes after addition of vermicompost as compared to farmyard manure in an alkaline soil with high lime content from semiarid Mediterranean region of Turkey. For this purpose, mixtures of soil and organic fertilizers in different doses were incubated under greenhouse condition. Soil samples collected in regular intervals were analyzed for biological parameters including dehydrogenase, β-glucosidase, urease, alkaline phosphatase activities, and total number of aerobic mesophilic bacteria. Even though soil dehydrogenase activity appeared to be dose-independent based on overall evaluation, organic amendments were found to elevate dehydrogenase activity when sampling periods are evaluated individually. β-glucosidase, urease, alkaline phosphatase activity, and aerobic mesophilic bacterial numbers in vermicompost treatments fluctuated but remained significantly above the control. A slight but statistically significant difference was detected between organic amendments in terms of urease activity. Vermicompost appeared to more significantly increase bacterial number in soil. Clearly, vermicompost has a potential to be used as an alternative to farmyard manure to improve and maintain soil biological activity in alkaline calcareous soils from the Mediterranean region of Turkey. Further studies are needed to assess its full potential for these soils.

  5. Schoolground Soil Studies.

    Science.gov (United States)

    Doyle, Charles

    1978-01-01

    Outlined are simple activities for studying soil, which can be conducted in the schoolyard. Concepts include soil profiles, topsoil, soil sizes, making soil, erosion, slope, and water absorption. (SJL)

  6. Preliminary Mapping and Characterisation of Soils in the Pirin Mountains (Bulgaria)

    Institute of Scientific and Technical Information of China (English)

    Maika L(a)Biger; J(o)rg Seheithauer; Karsten Grunewald

    2008-01-01

    Soft types, humus types and vegetation as well as their hypsometric variation were analysed in terms of sequences in the northern part of the high mountains of the Pirin National Park at altitudes between 1000 and 2400 m a.s.l. The study area is characterised by a large variety of natural parameters like petrology (mainly marble and granite), morphology (different slope deposits, exposition) and the orographic climate gradient. Statistical analyses using these parameters provided a basis for the soil group classification of the sites. Based on a Digital Terrain Model (DTM) and a geological map of the Pirin National Park, the results of these statistical analyses were used to generate a "map of potential soft groups" (regionalisation using GIS). Six potential soil groups could be determined. The resulting map exhibits a confidence level of 68% on 74.4% of the covered area. Rendzic Leptosols, in combination with Folio Histosols and Histi-lithic Leptosols occur in the alpine and subalpine regions on calcareous substrates. With decreasing altitude they are replaced by a mosaic of Rendzic Leptosols, Phaeozems and an increasing occurrence of Cambic Umbrisols. Umbrisols found on silicatic substrates in the alpine region are replaced by Cambic Umbrisols with decreasing altitude as well. Hence, pedogenesis is characterised by increasing browning and depth of the soil profiles with decreasing altitude. The pH-level is slightly acidic to neutral in lower zones and on calcareous rocky bases. Acidification increases in the subalpine zone. Soft pH decreases down to 4 on silicate subtrates. Typical humic values in mineral topsoils are 10 to 12%, and in organic layers of the softs above 2000 m a.s.l, they are even more. The C:N ratio closely ranges around 20 (median).

  7. Soils and cultural layers of ancient cities in the south of European Russia

    Science.gov (United States)

    Aleksandrovskii, A. L.; Aleksandrovskaya, E. I.; Dolgikh, A. V.; Zamotaev, I. V.; Kurbatova, A. N.

    2015-11-01

    Antique cities in the south of European Russia are characterized by a considerable thickness of their cultural layers (urbosediments) accumulated as construction debris and household wastes. Under the impact of pedogenesis and weathering in dry climate of the steppe zone, these sediments h