WorldWideScience

Sample records for undesirable soil characteristics

  1. Role of Fault Attributions and Other Factors in Adults' Attitudes Toward Hypothetical Children With an Undesirable Characteristic.

    Science.gov (United States)

    Wadian, Taylor W; Sonnentag, Tammy L; Jones, Tucker L; Barnett, Mark A

    2018-01-01

    A total of 184 adults read descriptions of six hypothetical children with various undesirable characteristics (i.e., being extremely overweight, extremely aggressive, extremely shy, a poor student, a poor athlete, displaying symptoms of attention deficit hyperactivity disorder). Following each description, the participants were asked to rate how much they disagree or agree that the child, the child's parents, and the child's biological condition (i.e., "something wrong inside the child's body or brain") are at fault for the onset and the perpetuation of the undesirable characteristic. In addition, the participants were asked to rate their attitude toward each child using a 100-point "feeling thermometer." Analyses of the participants' various fault attribution ratings revealed that they tended to agree more strongly that a child's parents and his/her biological condition are at fault for the onset and the perpetuation of the child's undesirable characteristic than is the child him/herself. Despite the participants' reluctance to blame a hypothetical child for his/her undesirable characteristic, regression analyses revealed that, in general, the more they blamed the child for the onset of his/her undesirable characteristic, the more negative their attitude was toward the child. However, the participants' ratings of the extent to which the child's parents or biological condition are at fault for the onset and the perpetuation of the child's undesirable characteristic were not found to be associated with their attitude toward any of the children. Similarities and differences between the present findings and those reported in prior studies involving younger individuals are addressed.

  2. Children's Perceptions of Hypothetical Peers With Undesirable Characteristics: Role of the Peers' Desire to Change, Source of Effort to Change, and Outcome.

    Science.gov (United States)

    Barnett, Mark A; Sonnentag, Tammy L; Wadian, Taylor W; Jones, Tucker L; Langley, Courtney A

    2015-01-01

    The present study, involving sixth- to eighth-grade students, is an extension of a prior investigation (Barnett, Livengood, Sonnentag, Barlett, & Witham, 2010) that examined children's perceptions of hypothetical peers with various undesirable characteristics. Results indicate that children's perceptions of hypothetical peers with an undesirable characteristic are influenced by the peers' desire to change, the source of effort to change, and the peers' success or failure in changing the characteristic. The children anticipated responding more favorably to peers who were successful in overcoming an undesirable characteristic than peers who were unsuccessful. Regardless of the peers' outcome, the children anticipated responding more favorably to peers who tried to change than peers who relied on the effort of adult authorities to motivate change. The children perceived successful peers as experiencing more positive affect than their unsuccessful counterparts, especially if the success was presented as a fulfillment of the peers' desire to change their undesirable characteristic. Finally, the children's ratings reflected the belief that, among peers who failed to change their undesirable characteristic, lacking the desire to change increases the relative likelihood that the characteristic will be permanent.

  3. Soil shrinkage characteristics in swelling soils

    International Nuclear Information System (INIS)

    Taboada, M.A.

    2004-01-01

    The objectives of this presentation are to understand soil swelling and shrinkage mechanisms, and the development of desiccation cracks, to distinguish between soils having different magnitude of swelling, as well as the consequences on soil structural behaviour, to know methods to characterize soil swell/shrink potential and to construct soil shrinkage curves, and derive shrinkage indices, as well to apply them to assess soil management effects

  4. SMEX03 Ancillary Soil Characteristics Data, Alabama

    Data.gov (United States)

    National Aeronautics and Space Administration — The SMEX03 Ancillary Soil Characteristics data set contains data for the regional study areas of Alabama, Georgia, and Oklahoma, USA as part of the 2003 Soil...

  5. Effect of Biochar on Soil Physical Characteristics

    DEFF Research Database (Denmark)

    Sun, Zhencai; Møldrup, Per; Vendelboe, Anders Lindblad

    Biochar addition to agricultural soil has been reported to reduce climate gas emission, as well as improve soil fertility and crop productivity. Little, however, is known about biochar effects on soil structural characteristics. This study investigates if biochar-application changes soil structural...... characteristics, as indicated from water retention and gas transport measurements on intact soil samples. Soil was sampled from a field experiment on a sandy loam with four control plots (C) without biochar and four plots (B) with incorporated biochar at a rate of 20 tons per hectare (plot size, 6 x 8 m). The C......-gas diffusivity on intact 100cm3 soil samples (5 replicates in each plot). We found that biochar application significantly decreased soil bulk density, hereby creating higher porosity. At the same soil-water matric potential, all the soil-gas phase parameters (air-filled porosity, air permeability and gas...

  6. Soil and forest floor characteristics

    Science.gov (United States)

    Ralph E. J. Boerner; Sherri J. Morris; Kelly L. M. Decker; Todd F. Hutchinson

    2003-01-01

    The soils of the four study areas in southern Ohio were dominated by silt loams derived from sandstones and shales. The soils at Bluegrass Ridge (BR) had significantly more clay and sand and significantly less silt than soils of the other study areas. Total inorganic N (TIN) and available NH4 were greatest in soils from Watch Rock (WR) and least...

  7. Importance of soil physical characteristics for petroleum ...

    African Journals Online (AJOL)

    Public PCs

    effective applying of hydrocarbons phytoremediation depends mainly on the soil and plant types and conditions and microbial ... for phytoremediation should have proper physical, chemical and biological characteristics to let the plant grow well and .... plant uptake and adsorption by soil particles or organic matter. Almost.

  8. Filtering Undesirable Flows in Networks

    NARCIS (Netherlands)

    Polevoy, G.; Trajanovski, S.; Grosso, P.; de Laat, C.; Gao, X.; Du, H.; Han, M.

    2017-01-01

    We study the problem of fully mitigating the effects of denial of service by filtering the minimum necessary set of the undesirable flows. First, we model this problem and then we concentrate on a subproblem where every good flow has a bottleneck. We prove that unless P=NP, this subproblem is

  9. Morphological characteristics and classification of soils derived from ...

    African Journals Online (AJOL)

    Variation in soil characteristics is usually a reflection of the difference in materials from which the soil was formed. This study sought to investigate the characteristics of soils formed on different parent materials with a view to classifying them. This study was carried out in selected soils derived from three major types of parent ...

  10. [Soil taxonomy on the basis of reflectance spectral characteristics].

    Science.gov (United States)

    Liu, Huan-Jun; Zhang, Bai; Zhang, Yuan-Zhi; Song, Kai-Shan; Wang, Zong-Ming; Li, Fang; Hu, Mao-Gui

    2008-03-01

    Soil spectral reflectance is the comprehensive representation of soil physical and chemical parameters, and its study is the physical basis for soil remote sensing and provides a new way and standard for soil properties themselves' research. Soil room spectra significantly correlate with that derived from hyperspectral images. So the room spectra are very important for soil taxonomy and investigation. To seek for the feasibility of soil taxonomy on the basis of topsoil reflectance spectral characteristics, and provide the theory foundation for quick soil taxonomy based on remote sensing methods, the spectral reflectance in the visible and near infrared region (400-2 500 nm) of 248 soil samples (black soil, chernozem, meadow soil, blown soil, alluvial soil) collected from Nongan county, Jilin province was measured with a hyperspectral device in room, and the soil spectral characteristics were determined with continuum removal method, and soil spectral indices (spectral absorption area, depth and asymmetry) were computed, which were introduced into BP network models as external input variables. The models consist of three layers (input, output and hidden layer), the training function is "TRAINLM", learning function "LEARNGDM", and transferring function "TAN SIG". The results showed that: (1) There are some differences among different soils in their spectral characteristics, but with similar parental matrix and climate, the spectral differences of soils in Nongan county are not significant. So it's difficult to analyze soil spectral characteristics based on soil reflectance. (2) The curves after continuum removal strengthened soil spectral absorption characteristics, and simplified soil spectral analysis. The soil spectral curves in Nongan county mainly have five spectral absorption vales at 494, 658, 1 415, 1 913 and 2 206 nm, and the former two vales are caused by soil organic matter, Fe and mechanical composition, the latter three are due to soil moisture; the

  11. Isotopic-tracer-aided studies on undesirable effects of heavy metals in the soil-plant system. Part of a coordinated programme on isotopic-tracer-aided studies of agrochemical residue - soil biota interactions

    International Nuclear Information System (INIS)

    Oberlaender, H.E.

    1982-07-01

    Uptake of isotopically labelled mercury (Hg-203), cadmium (Cd-115m) and zinc (Zn-65) from a calcareous chernozem and a podzolized brown earth by spring and winter varieties of wheat, rye and barley was investigated in pot experiments carried out until maturity of the plants. The labelled heavy metals, applied at concentrations innocuous to plant growth (0.5 ppm Hg or Cd, 50 ppm Zn) were determined radiometrically in the straw and in the grains of the harvested plants, as well as in the milling products (bran, semolina and flour) obtained by standard procedures of grain processing. Uptake of mercury was several hundred times smaller than the uptake of cadmium, if both metals were applied to the soil in equal amounts. Whereas the uptake of mercury from the acid soil was insignificant or not detectable, cadmium was taken up from this soil at a much higher rate than from the alkaline soil. Thus, not mercury, but cadmium imposes the greatest hazard on the food chain. Winter varieties of cereals took up more mercury and cadmium than did spring varieties. The content of heavy metals in the plants decreased considerably when plants approached maturity. During translocation through the plants the metals were gradually retained when passing from the stalks (''straw'') into the grains, and from the seed-cover (''bran'') into the endosperm (''flour''). The heavy metal contents of the grain fractions decreased in the order: bran > semolina > flour. Concentrations of heavy metals in flour were 3-8 times smaller than in straw, showing that flour is least affected by heavy metal pollution of cereals via the soil. The metal content of the various flour types was correlated with their percentage of bran and with their ash content. By adding an ion-exchanger to the soil the pattern of relative distribution of heavy metals in mature plants was not changed, but the cadmium content of all cereal products was considerably lowered

  12. Electrochemical characterization of corrosion in materials of grounding systems, simulating conditions of synthetic soils with characteristics of local soils

    Science.gov (United States)

    Salas, Y.; Guerrero, L.; Vera-Monroy, S. P.; Blanco, J.; Jimenez, C.

    2017-12-01

    The integrity of structures buried in earthing becomes relevant when analysing maintenance and replacement costs of these systems, as the deterioration is mainly due to two factors, namely: the failures caused in the electrical systems, which are due to the system. Failure in earthing due to corrosion at the interface cause an alteration in the structure of the component material and generates an undesirable resistivity that cause malfunction in this type of protection systems. Two local soils were chosen that were categorized as sandy loam and clay loam type, whose chemical characteristics were simulated by means of an electrolyte corresponding to the amount of ions present determined by a soil characterization based on the CICE (effective cation exchange coefficient), which allows us to deduce the percentage of chloride and sulphate ions present for the different levels established in the experimental matrix. The interaction of these soils with grounding electrodes is a complex problem involving many factors to consider. In this study, the rates and corrosion currents of the different soils on two types of electrodes, one copper and the other AISI 304 stainless steel, were approximated by electrochemical techniques such as potentiodynamic curves and electrochemical impedance spectra. Considerably higher speeds were determined for copper-type electrodes when compared to those based on steel. However, from the Nyquist diagrams, it was noted that copper electrodes have better electrical performance than steel ones. The soil with the highest ionic activity turned out to be the sandy loam. The clay loam soil presents a tendency to water retention and this may be the reason for the different behaviour with respect to ionic mobility. The diffusion control in the steel seems to alter the ionic mobility because its corrosion rates proved to be very similar regardless of the type of soil chemistry. In general, corrosion rates fell since tenths of a millimetre every year to

  13. Revamping of entisol soil physical characteristics with compost treatment

    Science.gov (United States)

    Sumono; Loka, S. P.; Nasution, D. L. S.

    2018-02-01

    Physical characteristic of Entisol soil is an important factor for the growth of plant. The aim of this research was to know the effect of compost application on physical characteristics of Entisol soil. The research method used was experimental method with 6 (six) treatments and 3 replications of which K1 = 10 kg Entisol soil without compost, K2 = 9 Kg Entisol soil with 1 kg compost, K3 = 8 kg Entisol soil with 2 kg compost, K4 = 7 kg Entisol soilwith3 kg compost, K5 = 6 kg Entisol soil with 4 kg compost and K6 = 5 kg Entisol soil with 5 kg compost. The observed parameters were soil texture, soil organic matter, soil thickness, porosity, soil pore size, soil permeability and water availability. The results showed that the Entisol soil texture was loamy sand texture, the value of soil organic matter ranged from 0.74% to 4.69%, soil thickness ranged from 13.83 to 20.16 cm, porosity ranged from16% to 37%, soil pore size ranged from 2.859 to 5.493 µm, permeability ranged from 1.24 to 5.64 cm/hour and water availability ranged from 6.67% to 9.12% by each treatment.

  14. An alternative to soil taxonomy for describing key soil characteristics

    Science.gov (United States)

    Duniway, Michael C.; Miller, Mark E.; Brown, Joel R.; Toevs, Gordon

    2013-01-01

    We are pleased to see the letter by Schimel and Chadwick (Front Ecol Environ 2013; 11[8]: 405–06), highlighting the importance of soil characterization in ecological and biogeochemical research and explaining the value of soil taxonomy, and we agree with the authors that reporting soil

  15. Relation of some Soil Water-transmission Characteristics to some ...

    African Journals Online (AJOL)

    A study was conducted to determine soil physical properties of an Alfisol constituting the soil of a proposed tillage and irrigation water management field laboratory and to relate the physical properties to the water transmission characteristics. The soil was found to be mainly sandy loam on the surface with high infiltration ...

  16. Comparative study of soil physical characteristics of Jaipur district ...

    African Journals Online (AJOL)

    A major flood in year 1981 in Jaipur district resulted into huge erosion of the top fertile soil and leaving the land unproductive for agriculture production. The present study was carried in Jaipur district of Rajasthan state to measure physical characteristics of the soil samples from different districts of Jaipur. Soils samples were ...

  17. Soil Characteristics, Microbial Compostion of Plot, Leaf Count and ...

    African Journals Online (AJOL)

    Field trials were conducted in the Experimental Garden, Department of Plant Biology and Biotechnology. The soil was subjected to analysis at the Soil Science Department, University of Benin to determine its characteristics and suitability for the growth of these arable crops. The soil microbial count was 6.25 X 105 and 1.34 ...

  18. ISLSCP II Global Gridded Soil Characteristics

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set provides gridded data for selected soil parameters derived from data and methods developed by the Global Soil Data Task, an international collaborative...

  19. foundations on expansive soils introduction characteristic

    African Journals Online (AJOL)

    FOUNDATIONS ON EXPANSIVE SOILS. Girma Tessema. Ethiopian Building Construction Authority. Ministry of Construction, Addis Ababa. INTRODUCTION. It is a welJ known fact that expansive soils pose considerable problems in civil engineering constructions. Structures built on such soils show movements which are.

  20. Physicochemical characteristics of communal rangeland soils along ...

    African Journals Online (AJOL)

    This study investigated the relative association of surface (0–20 cm) soil physicochemical properties, viz. electrical conductivity, cation exchange capacity (CEC), soil organic carbon, available phosphorus, particle size composition, soil aggregate stability and microbial respiration, along a toposequence in two vegetation ...

  1. Soil classification basing on the spectral characteristics of topsoil samples

    Science.gov (United States)

    Liu, Huanjun; Zhang, Xiaokang; Zhang, Xinle

    2016-04-01

    Soil taxonomy plays an important role in soil utility and management, but China has only course soil map created based on 1980s data. New technology, e.g. spectroscopy, could simplify soil classification. The study try to classify soils basing on the spectral characteristics of topsoil samples. 148 topsoil samples of typical soils, including Black soil, Chernozem, Blown soil and Meadow soil, were collected from Songnen plain, Northeast China, and the room spectral reflectance in the visible and near infrared region (400-2500 nm) were processed with weighted moving average, resampling technique, and continuum removal. Spectral indices were extracted from soil spectral characteristics, including the second absorption positions of spectral curve, the first absorption vale's area, and slope of spectral curve at 500-600 nm and 1340-1360 nm. Then K-means clustering and decision tree were used respectively to build soil classification model. The results indicated that 1) the second absorption positions of Black soil and Chernozem were located at 610 nm and 650 nm respectively; 2) the spectral curve of the meadow is similar to its adjacent soil, which could be due to soil erosion; 3) decision tree model showed higher classification accuracy, and accuracy of Black soil, Chernozem, Blown soil and Meadow are 100%, 88%, 97%, 50% respectively, and the accuracy of Blown soil could be increased to 100% by adding one more spectral index (the first two vole's area) to the model, which showed that the model could be used for soil classification and soil map in near future.

  2. [Organic carbon and carbon mineralization characteristics in nature forestry soil].

    Science.gov (United States)

    Yang, Tian; Dai, Wei; An, Xiao-Juan; Pang, Huan; Zou, Jian-Mei; Zhang, Rui

    2014-03-01

    Through field investigation and indoor analysis, the organic carbon content and organic carbon mineralization characteristics of six kinds of natural forest soil were studied, including the pine forests, evergreen broad-leaved forest, deciduous broad-leaved forest, mixed needle leaf and Korean pine and Chinese pine forest. The results showed that the organic carbon content in the forest soil showed trends of gradual decrease with the increase of soil depth; Double exponential equation fitted well with the organic carbon mineralization process in natural forest soil, accurately reflecting the mineralization reaction characteristics of the natural forest soil. Natural forest soil in each layer had the same mineralization reaction trend, but different intensity. Among them, the reaction intensity in the 0-10 cm soil of the Korean pine forest was the highest, and the intensities of mineralization reaction in its lower layers were also significantly higher than those in the same layers of other natural forest soil; comparison of soil mineralization characteristics of the deciduous broad-leaved forest and coniferous and broad-leaved mixed forest found that the differences of litter species had a relatively strong impact on the active organic carbon content in soil, leading to different characteristics of mineralization reaction.

  3. compressibility characteristics of black cotton soil admixed

    African Journals Online (AJOL)

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    The British method [26] for determination of. Atterberg's limits such as liquid limit, plastic limit and shrinkage limit was used. The Atterberg limit of the natural black cotton soil was first determined for proper classification of the soil using the American. Association for State Highway and Testing organization (AASHTO) and later ...

  4. compaction and consolidation characteristics of lateritic soil

    African Journals Online (AJOL)

    user

    ]. . Figure 4: Dry Density (Mgm-3) against Moisture Content. (%). Figure 5: e-logP Plots for Soil Samples at BH 1 and BH2. Figure 6:e-logP Plot for Soil Sample at BH 3. Figure 7: Relationship between Force and Penetration for. Samples BH1 ...

  5. Selected Physical and Chemical Characteristics of Soil

    African Journals Online (AJOL)

    soils of the basin. Based on soil color, texture, and land use, 12 pedons were opened in. Melka-Sedi farm and Werer Agricultural Research Center and studied for their physical and chemical ...... The replacement of exchangeable calcium and magnesium by sodium proceeds apace with salt accumulation under many ...

  6. Characteristics and engineering properties of residual soil of volcanic deposits

    Science.gov (United States)

    Wibawa, Y. S.; Sugiarti, K.; Soebowo, E.

    2018-02-01

    Residual soil knowledge of volcanic-sedimentary rock products provides important information on the soil bearing capacity and its engineering properties. The residual soil is the result of weathering commonly found in unsaturated conditions, having varied geotechnical characteristics at each level of weathering. This paper summarizes the results of the research from the basic engineering properties of residual soil of volcanic-sedimentary rocks from several different locations. The main engineering properties of residual soil such as specific gravity, porosity, grain size, clay content (X-Ray test) and soil shear strength are performed on volcanic rock deposits. The results show that the variation of the index and engineering properties and the microstructure properties of residual soil have the correlation between the depths of weathering levels. Pore volume and pore size distribution on weathered rock profiles can be used as an indication of weathering levels in the tropics.

  7. Soil mechanics. [characteristics of lunar soil from Apollo 17 flight lunar landing site

    Science.gov (United States)

    Mitchell, J. K.; Carrier, W. D., III; Costes, N. C.; Houston, W. N.; Scott, R. F.; Hovland, H. J.

    1973-01-01

    The soil mechanics experiment on the Apollo 17 mission to the Taurus-Littrow area of the moon is discussed. The objectives of the experiment were to determine the physical characteristics and mechanical properties of the lunar soil at the surface and subsurface in lateral directions. Data obtained on the lunar surface in conjunction with observations of returned samples of lunar soil are used to determine in-place density and porosity profiles and to determine strength characteristics on local and regional scales.

  8. Evaluation of phosphorus sorption characteristics of soils from the ...

    African Journals Online (AJOL)

    The evaluation of phosphorus sorption characteristics of soils and their relation to soil properties from the Bambouto sequence of Baranka 1, Baranka 2, Femock 1 and Femock 2 has been studied. Phosphorus, an essential plant nutrient, is often not readily available to plants and this deficiency tends to limit plant growth.

  9. Physical, Chemical and Mineralogical Characteristics of Important Mississippi Soils

    Science.gov (United States)

    R. R. Bruce; W. A. Raney; W. M. Broadfoot; H. B. Vanderford

    1958-01-01

    To realize the crop production potential of soils it is necessary to first have a knowledge of their chemical, physical and biological properties and reactions and then to so alter these properties and reactions to effect a medium optimum for plant growth. In the past, soils have been classified primarily on the basis of physical characteristics observable in the field...

  10. Upscaling soil saturated hydraulic conductivity from pore throat characteristics

    Science.gov (United States)

    Upscaling and/or estimating saturated hydraulic conductivity Ksat at the core scale from microscopic/macroscopic soil characteristics has been actively under investigation in the hydrology and soil physics communities for several decades. Numerous models have beendeveloped based on different approac...

  11. characteristics and classification of the soils of gonde

    African Journals Online (AJOL)

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    ABSTRACT: Samples were collected from genetic horizons of representative soil profiles to study the morphological and physicochemical characteristics and to classify the soils of Gonde micro- catchment in Arsi highlands (Ethiopia) located at 70° 32' 24” to 70° 34' 28” N and 39° 13' 15” to 39° 19'. 02” E. The study identified ...

  12. Land Resources of Russia -- Maps of Soil Characteristics, Version 1

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set consists of maps of various soil characteristics for all of Russia. The maps are available as ESRI Shapefiles and they are accompanied by databases of...

  13. Geochemical and Physical Characteristics of Iraqi Dust and Soil Samples

    Science.gov (United States)

    2004-10-08

    Report: Geochemical and Physical Characteristics of Iraqi Dust and Soil Samples iv ABBREVIATIONS LIST Acronyms ASTM American Society for Testing...gallons of Militec-1 gun lubricant were donated to DRI by 9 Militec, Inc. (11828 Pika Drive, Waldorf, Maryland). All three lubricants also serve as...Report: Geochemical and Physical Characteristics of Iraqi Dust and Soil Samples 37 REFERENCES ASTM ( American Society for Testing and Materials). 2000

  14. Conservation agriculture effects on soil pore characteristics

    DEFF Research Database (Denmark)

    Munkholm, Lars Juhl; Abdollahi, Lotfollah

    Conservation tillage in combination with crop rotation, residue management and cover crops are key components of conservation agriculture. A positive long-term effect of applying all components of conservation agriculture on soil structural quality is expected. However, there is a lack...

  15. Physicochemical characteristics of geophagic clayey soils from ...

    African Journals Online (AJOL)

    ONOS

    2010-09-06

    Sep 6, 2010 ... Physicochemical properties of geophagic clayey soils from South Africa and Swaziland were determined in order to appreciate their capability to perform the functions for which they are consumed and possible consequences of the practice in humans. Tests conducted included colour, texture, pH, electrical ...

  16. Importance of soil physical characteristics for petroleum ...

    African Journals Online (AJOL)

    Public PCs

    Wang et al. (2012) and Waqas et al. (2014) also reported the effects of amendments like compost and sewage sledges and biochar on remediation of some. PAHs. Soil texture, by controlling bioavailability of the plant nutrients and the contaminants would change the phytoremediation result (Figueiredo et al., 2016). This is.

  17. Cycles of undesirable substances in the food chain

    International Nuclear Information System (INIS)

    2012-01-01

    The working group ''Carry over of undesirable substances in animal feed'' at the Federal Ministry of Food, Agriculture and Forestry (BMELV) in cooperation with the Institute of Animal Nutrition of the Friedrich-Loeffler-Institute (FLI) performed on 27 and 28 October 2011 in Braunschweig a workshop on ''cycles of undesirable substances in Food Chain ''. The aim of the workshop was to present the latest findings of research and Carry over Recommendations of the Carry over - Working Group on undesirable substances in feed and production processes of the feed industry, to evaluate and discuss about this with representatives from science, business and management and to work out the further research and action need. The focus of the considerations were the pathways, the carry over and the Exposure to dioxins and other halogenated hydrocarbons, the effects of Mycotoxins in feed and starting points for preventive measures, the soil contamination and the exposure of humans and animals by cadmium and case studies on Nitrite in feed, antibiotics in plants and residues of pesticides and radionuclides in feed. Furthermore the risks associated with specified manufacturing processes of feed are considered, especially the used materials that come into contact with animal feed, and the risks from nanotechnology. [de

  18. Response Characteristics of Soil Fractal Features to Different Land Uses in Typical Purple Soil Watershed

    Science.gov (United States)

    Luo, Bang-lin; Chen, Xiao-yan; Ding, Lin-qiao; Huang, Yu-han; Zhou, Ji; Yang, Tian-tian

    2015-01-01

    As a fundamental characteristic of soil physical properties, the soil Particle Size Distribution (PSD) is important in the research on soil moisture migration, solution transformation, and soil erosion. In this research, the PSD characteristics with distinct methods in different land uses are analyzed. The results show that the upper bound of the volume domain of the clay domain ranges from 5.743μm to 5.749μm for all land-use types. For the silt domain of purple soil, the value ranges among 286.852~286.966 μm. For all purple soil land-use types, the order of the volume domain fractal dimensions is Dclayfractal dimension (Dvi) are higher than the corresponding parameter values from the United States Department of Agriculture (Dvi(U)). The correlation study between the volume domain fractal dimension and the soil properties shows that the intensity of correlation to the soil texture and soil organic matter has the order as: Dsilt>Dsilt(U)>Dsand (U)>Dsand and Dsilt>Dsilt(U)>Dsand>Dsand(U), respectively. As it is compared with all Dvi, the Dsilt has the most significant correlativity to the soil texture and organic matter in different land uses of the typical purple soil watersheds. Therefore, Dsilt will be a potential indictor for evaluating the proportion of fine particles in the PSD, as well as a key measurement in soil quality and productivity studies. PMID:25856376

  19. A study of soil surface characteristics in a small watershed in the hilly, gullied area on the Chinese Loess Plateau

    NARCIS (Netherlands)

    Liu Guobin,; Xu Mingxiang,; Ritsema, C.J.

    2003-01-01

    Soil surface characteristics are closely related to soil surface depressional storage, infiltration, runoff generation and soil erosion, especially in highly erodible loess soil. Soil surface random roughness, soil cohesion and aggregate stability are necessary parameters in the Limburg Soil Erosion

  20. Phosphate sorption characteristics of European alpine soils

    Czech Academy of Sciences Publication Activity Database

    Kaňa, Jiří; Kopáček, Jiří; Camarero, L.; Garcia-Pausas, J.

    2011-01-01

    Roč. 75, č. 3 (2011), s. 862-870 ISSN 0361-5995 R&D Projects: GA ČR(CZ) GA526/09/0567; GA AV ČR(CZ) KJB600960907 Grant - others:EU EMERGE(CZ) EVK1-CT-1999-00032 Institutional research plan: CEZ:AV0Z60170517 Keywords : phosphate sorption * alpine soils * acidification Subject RIV: DJ - Water Pollution ; Quality Impact factor: 1.979, year: 2011

  1. Associations between soil texture, soil water characteristics and earthworm populations of grassland

    DEFF Research Database (Denmark)

    Holmstrup, Martin; Lamandé, Mathieu; Torp, Søren Bent

    2011-01-01

    The aim of the present study was to investigate the relationships between soil physical characteristics and earthworms in a regional-scale field study in Denmark. The earthworm populations along within-field gradients in soil texture were quantified at five field sites, representing dominant soil...... types of Denmark. Eleven earthworm species were found, but populations were mainly dominated by Aporrectodea tuberculata and A. longa. Despite considerable variation in soil parameters across the five study sites the results suggest that the biomass of anecic worms (or A. longa as a species......) was not causally associated with the soil parameters studied. This indicates that there must be other causal factors associated with the abundance (and composition) of anecic worms that are not among the soil texture and structure parameters studied. On the other hand, soil texture (Coarse sand) was associated...

  2. Soil Chemical Characteristics of Organic and Conventional Agriculture

    Directory of Open Access Journals (Sweden)

    Muhammad Abdul Aziz

    2016-01-01

    Full Text Available Use of chemical fertilizers and pesticides on intensive land of both lowland and upland food crops have been shown to increase agricultural productivity significantly. Research aimed to study soil chemical characteristics and soil pesticide residues at some crops of organic and conventional farms. The research was carried out in Laboratory of Soil Chemistry, Indonesian Soil Research Institute and in Laboratory of Agrochemical Residue, Indonesian Agricultural Environment Research Institute, Bogor from February to July 2015. Soil samples at 0-10 cm depth were taken compositely from broccoli (Brassica oleracea, carrots (Daucus carota, maize (Zea mays, and tomatoes (Solanum lycopersicum farms in Bogor Regency as well as from rice field in Tasikmalaya Regency at both organic and conventional farms. Soil chemical characteristics were analyzed include: soil organic-C (Walkey and Black, total-N (Kjeldahl, potential-P (HCl 25%, available-P (Olsen, potential-K (HCl 25%, available-K (NH4OAc 1 N pH 7, CEC (NH4OAc 1 N pH 7, and pH (soil : water = 1: 5, while pesticide residues included levels of organochlorine (lindane, aldrin, heptaklor, dieldrin, DDT, endosulfan; organophosphates (diazinon, fenitrotin, metidation, paration, profenofos; and carbamates (carbofuran, MIPC, BPMC in the soil by using Gas Chromatography method. Results showed that levels of soil organic-C, total-N, potential and available-P, potential and available-K, CEC, pH at organic farms were higher than those at conventional farms. Some pesticide residues compound (organochlorines, organophosphates, and carbamates were detected at conventional farm, while those at organic farm were not detected (trace.

  3. The effect of some soil characteristics on soil radon concentration and radon exhalation from soil surface

    International Nuclear Information System (INIS)

    Sun, Kainan; Cheng, Jianping; Guo, Qiuju

    2004-01-01

    To find out the impacts of soil characters on radon concentration in soil and radon exhalation from soil, field measurements on soil radon concentrations (60 cm under the soil surface) and radon exhalation rate from soil surface were carried out in totally 31 points with different types of soil in three cities in both South and North China. Soil radium contents, water contents, soil porosity and grain size were concretely analyzed in our laboratory. The linear simulation was used to analyze the above data. The results showed that radon exhalation rate from soil and radon concentrations in soil have direct proportion to soil radium contents. Rather high radium content and radon exhalation rate were measured in Guiyang area, 67±28Bq/Kg and 40±59 mBq/m 2 ·s, however no high soil radon concentration was found due to the difficulties in the measurements on clay soils with high saturation. Compared with soil radium contents, radon exhalation rate from soil and soil radon concentrations are more easily impacted by soil characters and change in a rather large range. (author)

  4. [Analysis of XRD spectral characteristics of soil clay mineral in two typical cultivated soils].

    Science.gov (United States)

    Zhang, Zhi-Dan; Luo, Xiang-Li; Jiang, Hai-Chao; Li, Qiao; Shen, Cong-Ying; Liu, Hang; Zhou, Ya-Juan; Zhao, Lan-Po; Wang, Ji-Hong

    2014-07-01

    The present paper took black soil and chernozem, the typical cultivated soil in major grain producing area of Northeast, as the study object, and determinated the soil particle composition characteristics of two cultivated soils under the same climate and location. Then XRD was used to study the composition and difference of clay mineral in two kinds of soil and the evolutionary mechanism was explored. The results showed that the two kinds of soil particles were composed mainly of the sand, followed by clay and silt. When the particle accumulation rate reached 50%, the central particle size was in the 15-130 microm interval. Except for black soil profile of Shengli Xiang, the content of clay showed converse sequence to the central particle in two soils. Clay accumulated under upper layer (18.82%) in black soil profile while under caliche layer (17.41%) in chernozem profile. Clay content was the least in parent material horizon except in black profile of Quanyanling. Analysis of clay XRD atlas showed that the difference lied in not only the strength of diffraction peak, but also in the mineral composition. The main contents of black soil and chernozem were both 2 : 1 clay, the composition of black soil was smectite/illite mixed layer-illite-vermiculite and that of chernozem was S/I mixture-illite-montmorillonite, and both of them contained little kaolinite, chlorite, quartz and other primary mineral. This paper used XRD to determine the characteristics of clay minerals comprehensively, and analyzed two kinds of typical cultivated soil comparatively, and it was a new perspective of soil minerals study.

  5. Response characteristics of soil fractal features to different land uses in typical purple soil watershed.

    Directory of Open Access Journals (Sweden)

    Bang-lin Luo

    Full Text Available As a fundamental characteristic of soil physical properties, the soil Particle Size Distribution (PSD is important in the research on soil moisture migration, solution transformation, and soil erosion. In this research, the PSD characteristics with distinct methods in different land uses are analyzed. The results show that the upper bound of the volume domain of the clay domain ranges from 5.743 μm to 5.749 μm for all land-use types. For the silt domain of purple soil, the value ranges among 286.852~286.966 μm. For all purple soil land-use types, the order of the volume domain fractal dimensions is D clayD silt(U>D sand (U>D sand and D silt>D silt(U>D sand>D sand(U, respectively. As it is compared with all Dvi, the D silt has the most significant correlativity to the soil texture and organic matter in different land uses of the typical purple soil watersheds. Therefore, Dsilt will be a potential indictor for evaluating the proportion of fine particles in the PSD, as well as a key measurement in soil quality and productivity studies.

  6. Soil Characteristics Driving Arbuscular Mycorrhizal Fungal Communities in Semiarid Mediterranean Soils

    Science.gov (United States)

    Torres, Maria Pilar; Montesinos-Navarro, Alicia; Roldán, Antonio

    2016-01-01

    ABSTRACT We investigated communities of arbuscular mycorrhizal fungi (AMF) in the roots and the rhizosphere soil of Brachypodium retusum in six different natural soils under field conditions. We explored phylogenetic patterns of AMF composition using indicator species analyses to find AMF associated with a given habitat (root versus rhizosphere) or soil type. We tested whether the AMF characteristics of different habitats or contrasting soils were more closely related than expected by chance. Then we used principal-component analysis and multivariate analysis of variance to test for the relative contribution of each factor in explaining the variation in fungal community composition. Finally, we used redundancy analysis to identify the soil properties that significantly explained the differences in AMF communities across soil types. The results pointed out a tendency of AMF communities in roots to be closely related and different from those in the rhizosphere soil. The indicator species analyses revealed AMF associated with rhizosphere soil and the root habitat. Soil type also determined the distribution of AMF communities in soils, and this effect could not be attributed to a single soil characteristic, as at least three soil properties related to microbial activity, i.e., pH and levels of two micronutrients (Mn and Zn), played significant roles in triggering AMF populations. IMPORTANCE Communities of arbuscular mycorrhizal fungi (AMF) are main components of soil biota that can determine the productivity of ecosystems. These fungal assemblages vary across host plants and ecosystems, but the main ecological processes that shape the structures of these communities are still largely unknown. A field study in six different soil types from semiarid areas revealed that AMF communities are significantly influenced by habitat (soil versus roots) and soil type. In addition, three soil properties related to microbiological activity (i.e., pH and manganese and zinc levels

  7. Microstructure characteristics of cement-stabilized sandy soil using nanosilica

    Directory of Open Access Journals (Sweden)

    Asskar Janalizadeh Choobbasti

    2017-10-01

    Full Text Available An experimental program was conducted to explore the impact of nanosilica on the microstructure and mechanical characteristics of cemented sandy soil. Cement agent included Portland cement type II. Cement content was 6% by weight of the sandy soil. Nanosilica was added in percentages of 0%, 4%, 8% and 12% by weight of cement. Cylindrical samples were prepared with relative density of 80% and optimum water content and cured for 7 d, 28 d and 90 d. Microstructure characteristics of cement-nanosilica-sand mixtures after 90 d of curing have been explored using atomic force microscopy (AFM, scanning electron microscopy (SEM and X-ray diffraction (XRD tests. Effects of curing time on microstructure properties of cemented sandy soil samples with 0% and 8% nanosilica have been investigated using SEM test. Unconfined compression test (for all curing times and compaction test were also performed. The SEM and AFM tests results showed that nanosilica contributes to enhancement of cemented sandy soil through yielding denser, more uniform structure. The XRD test demonstrated that the inclusion of nanosilica in the cemented soil increases the intensity of the calcium silicate hydrate (CSH peak and decreases the intensity of the calcium hydroxide (CH peak. The results showed that adding optimum percentages of nanosilica to cement-stabilized sandy soil enhances its mechanical and microstructure properties.

  8. Undesirable effects after treatment with dermal fillers.

    Science.gov (United States)

    Rodrigues-Barata, Ana Rita; Camacho-Martínez, Francisco M

    2013-04-01

    Soft tissue augmentation is one of the most frequent techniques in cosmetic dermatology. Nowadays, there are a high number of available materials. Nonanimal hyaluronic acid (HA) is one of most useful fillers for lip augmentation and for treating nasolabial folds, marionette lines, and the dynamic wrinkles of the upper face. To evaluate the type and management of undesirable effects of nonanimal reticulated or stabilized HA observed in our cosmetic unit in the past 3 years. The consecutive patients using HA attending to our clinic in the past 3 years were divided into 3 categories, according to the time of presentation of the adverse reactions: immediate, early, and late-onset complications. All patients were treated. Twenty-three patients presented to our clinic complaining of complications after soft tissue augmentation with HA. Ten patients presented immediate-onset complications, 8 showed early-onset complications, and 5 cases complaint of late-onset complications. Treatment of the first group consisted of hyaluronidase injection, massage, and topical antibiotics. Early- and late-onset complications were treated with intralesional triamcinolone acetonide. All patients improved, with the exception of a woman with recurrent granulomas. Generally, undesirable effects of HA (immediate, early, or late onset) are not frequent, and when present, they improve if treated properly. Physicians need to be aware of these possible adverse events in order to establish proper treatment and prevent scarring or other sequelae.

  9. Correlative characteristic of cadmium in soils of steppe Dnieper region

    Directory of Open Access Journals (Sweden)

    N. M. Tsvetkova

    2015-09-01

    Full Text Available Much attention is paid to searching for methods of establishing environmental standards for objective assessment of admissibility of anthropogenic load on the biosphere. The main pollutants of the environment are xenobiotics; heavy metals such as cadmium occupy hold a special place among them. Cadmium is one of the most dangerous environmental toxic agents, belonging to the 1stclass of hazard. Due to insufficient and fragmented information available on the distribution of cadmium in the city edaphotopes, it’s necessary to conduct additional research, taking into account the properties of soils and the biological characteristics of every element. The paper shows the ratio of cadmium in soils and soil-forming rocks of steppe Dnieper region. Environmental assessment of cadmium content in Dniprodzerzhinsk city soilsis made, and the problem of topsoil contamination of the city as a territory of high anthropogenic load is considered. It is found that the content of cadmium down the profile in natural soil increases. Enrichment of the topsoil with cadmium occurs due to contamination. The value of movable forms content, expressed as a percentage of the total content, varies from 12% to 70%, providing the evidence of the technogenic origin of cadmium in Dniprodzerzhinsk city topsoil. General and proximate correlation analyses of interrelation of soil cadmium and specifically selected characteristics of soil (pH, humus, sulfate ions, dry solid, chloride ions, total alkalinity, hygroscopic moisture were made. It is established that cadmium concentration in the movable forms of natural soils of the steppe Dnieper region depends primarily on pH value. With the increase in pH value, concentration of movable cadmium in soil increases.

  10. prediction of characteristics of coastal plain soils using terrain ...

    African Journals Online (AJOL)

    clay, electrical and hydraulic conductivity, bulk density, pH, exchangeable calcium, magnesium, sodium, potassium and acidity ... significantly correlated with clay and pH (H2O), while SPI and CTI correlated significantly with clay, pH, organic carbon and ... Key words: coastal plain sands, DEM, soil characteristics, modelling.

  11. Characteristics and Management of Fadama Soils of Barkin Sale ...

    African Journals Online (AJOL)

    Some nutrient management measures for these soils for sustainable rice production such as use of green manure, application of rock phosphate, rice straw mulching/incorporation and planting of promiscuous soybean variety were recommended for sustainable rice production in the area. Key words: Characteristic ...

  12. Soil Characteristics of Crusted outside and Subcanopy Areas of four ...

    African Journals Online (AJOL)

    The results on compaction, salinity, pH, water holding capacity, respiration and organic carbon supported the model. The crust:shrub ratio is crucial for the functioning and sustained productivity of the system. Keywords: Soil characteristics; shrub subcanopy; crust; sink-source, Negev desert [IJARD Vol.3 2002: 162-170] ...

  13. Physicochemical Characteristics of Soil from Selected Solid Waste ...

    African Journals Online (AJOL)

    This study examined the nutrient status and textural characteristics of soil from solid waste dumpsites in the city of Port Harcourt. The study was carried out in five solid waste dump sites alongside their respective controls located at Iwofe, Eliozu, Choba, Rumuokwuta and Ozuoba within the city of Port Harcourt for two ...

  14. Influence of water and soil characteristics on abundance of ...

    African Journals Online (AJOL)

    Influence of water and soil characteristics on abundance of chlorophyll 'A\\' in Elechi creek, Niger Delta, Nigeria. UU Gabriel, MB Inko-Tariah, NO Olu, OA Akinrotimi. Abstract. No Abstract. International Journal of Natural and Applied Sciences Vol. 4 (3) 2008: pp. 174-180. Full Text: EMAIL FULL TEXT EMAIL FULL TEXT

  15. Physicochemical Characteristics of Soil from Selected Solid Waste ...

    African Journals Online (AJOL)

    ADOWIE PERE

    ABSTRACT: This study examined the nutrient status and textural characteristics of soil from solid waste dumpsites in the city of Port Harcourt. The study was carried out in five solid waste dump sites alongside their respective controls located at Iwofe, Eliozu, Choba, Rumuokwuta and Ozuoba within the city of Port Harcourt ...

  16. Impact of modified soil thermal characteristic on the simulated ...

    Indian Academy of Sciences (India)

    In the present study, the influence of soil thermal characteristics (STC) on the simulated monsoon climate over south Asia is analyzed. The study was motivated by a common warm temperature bias over the plains of northern India that has been noticed in several global and regional climate models. To address this warm ...

  17. Correlation between soil chemical characteristics and soil-borne mycoflora in cucumber tunnels

    International Nuclear Information System (INIS)

    Qudsia, H.; Javaid, A.; Mahmood, R.; Akhtar, N.

    2017-01-01

    Twelve soil samples were collected from fields of cucumber (Cucumis sativus L.) tunnels from various localities of Lahore and Shekhupura districts, Pakistan. Soil samples were analyzed for various characteristics viz. pH, EC/sub e/, organic matter, nitrogen (N), phosphorus (P) and potassium (K). Soil mycoflora was isolated using dilution plate method. Soil pH, EC/sub e/, organic matter, N, P and K were in the range of 7.42-8.13, 107-2520 (meu S cm-1), 0.98-1.40%, 0.039-0.070%, 7-357 mg kg/sup -1/ and 88-946 mg kg/sup -1/ in different soil samples, respectively. A total of 18 fungal species belonging to 10 genera viz. Aspergillus, Alternaria, Cladosporium, Drechslera, Emericella, Fusarium, Mortierella, Mucor, Penicillium and Sclerotium were isolated from various soil samples. Saprophytic fungi were more prevalent than pathogenic ones. Number of colonies of saprophytic fungi ranged from 360-2754 g/sup -1/ soil in different samples. In contrast, number of pathogenic fungal colonies were limited to 1-234 g/sup -1/ soil. Number of colonies of pathogenic fungi were positively and significantly correlated with soil organic matter and nitrogen contents. This study concludes that high nitrogen and organic matter in cucumber tunnels favour population of pathogenic fungi. (author)

  18. Prediction of the Soil Water Characteristic from Soil Particle Volume Fractions

    DEFF Research Database (Denmark)

    Naveed, Muhammad; Møldrup, Per; Tuller, Markus

    2012-01-01

    (w)-model) for the SWC, derived from readily available soil properties such as texture and bulk density. A total of 46 undisturbed soils from different horizons at 15 locations across Denmark were used for model evaluation. The F-w-model predicts the volumetric water content as a function of volumetric fines content......Modeling water distribution and flow in partially saturated soils requires knowledge of the soil water characteristic (SWC). However, measurement of the SWC is challenging and time-consuming and, in some cases, not feasible. This study introduces two predictive models (F-w-model and A...... as a function of volumetric content of different particle size fractions (organic matter, clay, silt, and fine and coarse sands). The volumetric content of a particular soil particle size fraction was considered if it contributed to the pore size fraction still occupied with water at the given pF value. Hereby...

  19. The undesirable effects of neuromuscular blocking drugs

    DEFF Research Database (Denmark)

    Claudius, C; Garvey, L H; Viby-Mogensen, J

    2009-01-01

    Neuromuscular blocking drugs are designed to bind to the nicotinic receptor at the neuromuscular junction. However, they also interact with other acetylcholine receptors in the body. Binding to these receptors causes adverse effects that vary with the specificity for the cholinergic receptor...... in question. Moreover, all neuromuscular blocking drugs may cause hypersensitivity reactions. Often the symptoms are mild and self-limiting but massive histamine release can cause systematic reactions with circulatory and respiratory symptoms and signs. At the end of anaesthesia, no residual effect...... of a neuromuscular blocking drug should be present. However, the huge variability in response to neuromuscular blocking drugs makes it impossible to predict which patient will suffer postoperative residual curarization. This article discusses the undesirable effects of the currently available neuromuscular blocking...

  20. Analytical reliability analysis of soil-water characteristic curve

    Directory of Open Access Journals (Sweden)

    Johari A.

    2016-01-01

    Full Text Available The Soil Water Characteristic Curve (SWCC, also known as the soil water-retention curve, is an important part of any constitutive relationship for unsaturated soils. Deterministic assessment of SWCC has received considerable attention in the past few years. However the uncertainties of the parameters which affect SWCC dictate that the problem is of a probabilistic nature rather than being deterministic. In this research, a Gene Expression Programming (GEP-based SWCC model is employed to assess the reliability of SWCC. For this purpose, the Jointly Distributed Random Variables (JDRV method is used as an analytical method for reliability analysis. All input parameters of the model which are initial void ratio, initial water content, silt and clay contents are set to be stochastic and modelled using truncated normal probability density functions. The results are compared with those of the Monte Carlo (MC simulation. It is shown that the initial water content is the most effective parameter in SWCC.

  1. Experimental Research on Creep Characteristics of Nansha Soft Soil

    Directory of Open Access Journals (Sweden)

    Qingzi Luo

    2014-01-01

    Full Text Available A series of tests were performed to investigate the creep characteristics of soil in interactive marine and terrestrial deposit of Pearl River Delta. The secondary consolidation test results show that the influence of consolidation pressure on coefficient of secondary consolidation is conditional, which is decided by the consolidation state. The ratio of coefficient of secondary consolidation and coefficient of compressibility Ca/Cc is almost a constant, and the value is 0.03. In the shear-box test, the direct sheer creep failure of soil is mainly controlled by shear stress rather than the accumulation of shear strain. The triaxial creep features are closely associated with the drainage conditions, and consolidation can weaken the effect of creep. When the soft soil has triaxial creep damage, the strain rate will increase sharply.

  2. High Energy Moisture Characteristics: Linking Between Soil Physical Processes and Structure Stability

    Science.gov (United States)

    Water storage and flow in soils is usually complicated by the intricate nature of and changes in soil pore size distribution (PSD) due to modifications in soil structure following changes in agricultural management. The paper presents the Soil High Energy Moisture Characteristic (Soil-HEMC) method f...

  3. Innovative Methods for Soil DNA Purification Tested in Soils with Widely Differing Characteristics

    Czech Academy of Sciences Publication Activity Database

    Ságová-Marečková, Markéta; Čermák, Ladislav; Novotná, Jitka; Plháčková, Kamila; Forstová, Jana; Kopecký, Jan

    2008-01-01

    Roč. 74, č. 9 (2008), s. 2902-2907 ISSN 0099-2240 R&D Projects: GA AV ČR IAA6020410; GA AV ČR IAA600200519 Institutional research plan: CEZ:AV0Z50200510 Keywords : soil characteristic * dna * purification Subject RIV: EE - Microbiology, Virology Impact factor: 3.801, year: 2008

  4. Soil crusting regulator characteristics of some allic humid tropical soils from Colombia

    International Nuclear Information System (INIS)

    Arias, Dora M; Madero E E; Amezquita E

    2001-01-01

    It was collected soil samples within 5 cm of the surface from Amazonia soils in Caqueta (Macagual); Orinoquia in Meta (Carimagua), Casanare (Matazul) and Vichada (La Primavera); and in Andean region in Cauca (San Isidro) and Valle (CIAT, Palmira). In each of those sites, the International Center for Tropical Agriculture (CIAT) has many experiments to know the impact of land husbandry, leguminous associations and rotations and mulches on natural system. After evaluating weighed particle size, sand particle size, soil organic matter, iron, aluminum and silicon oxides, and fertility, it could cluster in three groups according to those characteristics and their importance in governing soil hazard crusting: la Primavera and Carimagua (high organic matter, oxides and fine sand but low in clay); Matazul and Macagual (low in organic matter, oxides and clay but variable sand values); and San Isidro (the greatest in Al 2 O 3 concentrations, high in Fe 2 O 3 clay and fine sand but the poorest in soil organic matter). Soil organic matter contents were significantly associated with the kind of management

  5. Determining soil hydrologic characteristics on a remote forest watershed by continuous monitoring of soil water pressures, rainfall and runoff.

    Science.gov (United States)

    L.R. Ahuja; S. A. El-Swaify

    1979-01-01

    Continuous monitoring of soil-water pressures, rainfall and runoff under natural conditions was tested as a technique for determining soil hydrologic characteristics of a remote forest watershed plot. A completely battery-powered (and thus portable) pressure transducer–scanner–recorder system was assembled for monitoring of soil-water pressures in...

  6. Study on soil water characteristics of tobacco fields based on canonical correlation analysis

    Directory of Open Access Journals (Sweden)

    Xiao-hou Shao

    2009-06-01

    Full Text Available In order to identify the principal factors influencing soil water characteristics (SWC and evaluate SWC effectively, the multivariate-statistical canonical correlation analysis (CCA method was used to study and analyze the correlation between SWC and soil physical and chemical properties. Twenty-two soil samples were taken from 11 main tobacco-growing areas in Guizhou Province in China and the soil water characteristic curves (SWCC and basic physical and chemical properties of the soil samples were determined. The results show that: (1 The soil bulk density, soil total porosity and soil capillary porosity have significant effects on SWC of tobacco fiels. Bulk density and total porosity are positively correlated with soil water retention characteristics (SWRC, and soil capillary porosity is positively correlated with soil water supply characteristics (SWSC. (2 Soil samples from different soil layers at the same soil sampling point show similarity or consistency in SWC. Inadequate soil water supply capability and imbalance between SWRC and SWSC are problems of tobacco soil. (3 The SWC of loamy clay are generally superior to those of silty clay loam.

  7. Adsorption and desorption characteristics of lindane, carbofuran and methyl parathion on various Indian soils

    International Nuclear Information System (INIS)

    Rama Krishna, K.; Philip, Ligy

    2008-01-01

    Adsorption and desorption characteristics of three insecticides on four Indian soils were studied. Insecticides used were representative of organochlorine, organophosphate, and carbomate groups. The order of adsorption of pesticides on soils was: lindane > methyl parathion > carbofuran. Compost soil had shown the maximum adsorption capacity. The order of adsorption capacity of various soils were: compost soil > clayey soil > red soil > sandy soil. Adsorption isotherms were better fitted to Freundlich model and K f values increased with increase in organic matter content of the soils. Thermodynamic parameters indicated favorable adsorption of all the three pesticides in four different soils. Adsorption was exothermic in nature. Distilled water desorbed 30-60% of adsorbed pesticides whereas; organic solvents were able to affect 50-80% of sorbed pesticides. Clay content and organic matter played a significant role in pesticide adsorption and desorption processes. Hysteresis effect was observed in red, clayey and compost soils. Hysteresis effect increased with increase in organic matter and clay content of the soils

  8. Effect of biochar on soil structural characteristics: water retention and gas transport

    DEFF Research Database (Denmark)

    Sun, Zhencai; Møldrup, Per; Vendelboe, Anders Lindblad

    Biochar addition to agricultural soil has been reported to reduce climate gas emission, as well as improve soil fertility and crop productivity. Little, however, is known about biochar effects on soil structural characteristics. This study investigates if biochar-application changes soil structural...... characteristics, as indicated from water retention and gas transport measurements on intact soil samples. Soil was sampled from a field experiment on a sandy loam with four control plots (C) without biochar and four plots (B) with incorporated biochar at a rate of 20 tons per hectare (plot size, 6 x 8 m). The C......-gas diffusivity on intact 100cm3 soil samples (5 replicates in each plot). We found that biochar application significantly decreased soil bulk density, hereby creating higher porosity. At the same soil-water matric potential, all the soil-gas phase parameters (air-filled porosity, air permeability and gas...

  9. Compaction and rotovation effects on soil pore characteristics of a loamy sand soil with contrasting organic matter content

    DEFF Research Database (Denmark)

    Eden, Marie; Schjønning, Per; Møldrup, Per

    2011-01-01

    The high input of mechanical energy in common agricultural practice can negatively affect soil structure. The impact of compaction (P) and rotovation (R) on soil pore characteristics was compared with those in soil from untreated reference (U) plots of a loamy sand soil receiving for 14 yr, either...... OF had larger porosity than that from treatment MF. Treatment P eliminated this difference and significantly reduced the volume of macropores. This interaction between soil organic matter content and mechanical impact was also reflected in the gas diffusion data. Specific air permeability was mainly...... only mineral fertilizer (MF) or, in addition, animal manure (OF). Undisturbed soil cores were taken from two separate fields in consecutive years at an identical stage in the crop rotation. We measured soil organic carbon (OC), soil microbial biomass carbon (BC), and hot-water extractable carbon (Chot...

  10. Intermittent hypoxia and cancer: Undesirable bed partners?

    Science.gov (United States)

    Almendros, Isaac; Gozal, David

    2017-08-14

    The deleterious effects of intermittent hypoxia (IH) on cancer biology have been primarily evaluated in the context of the aberrant circulation observed in solid tumors which results in recurrent intra-tumoral episodic hypoxia. From those studies, IH has been linked to an accelerated tumor progression, metastasis and resistance to therapies. More recently, the role of IH in cancer has also been studied in the context of obstructive sleep apnea (OSA), since IH is a hallmark characteristic of this condition. Such recent studies are undoubtedly adding more information regarding the role of IH on tumor malignancy. In terms of the IH patterns associated with OSA, this altered oxygenation paradigm has been recently proposed as a determinant factor in fostering cancer incidence and progression from both in vitro and in vivo experimental models. Here, we summarize all the available evidence to date linking IH effects on several types of cancer. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. Analysis of soil temperature harmonics and filtering characteristics ...

    African Journals Online (AJOL)

    Soil temperature determines the biological, chemical and physical processes taking place, and the energy and mass exchanges at the soil-temperature interface. The incident solar energy determines the periodic variation of the soil temperatures and the attenuation with depth. Harmonic analysis of soil temperatures at ...

  12. Plant tolerance to diesel minimizes its impact on soil microbial characteristics during rhizoremediation of diesel-contaminated soils

    Energy Technology Data Exchange (ETDEWEB)

    Barrutia, O., E-mail: oihana.barrutia@ehu.es [Department of Plant Biology and Ecology, University of the Basque Country/EHU, P.O. Box 644, E-48080 Bilbao (Spain); Garbisu, C.; Epelde, L. [NEIKER-Tecnalia, Soil Microbial Ecology Group, c/Berreaga 1, E-48160 Derio (Spain); Sampedro, M.C.; Goicolea, M.A. [Department of Analytical Chemistry, University of the Basque Country/EHU, E-01006 Vitoria (Spain); Becerril, J.M. [Department of Plant Biology and Ecology, University of the Basque Country/EHU, P.O. Box 644, E-48080 Bilbao (Spain)

    2011-09-01

    Soil contamination due to petroleum-derived products is an important environmental problem. We assessed the impacts of diesel oil on plants (Trifolium repens and Lolium perenne) and soil microbial community characteristics within the context of the rhizoremediation of contaminated soils. For this purpose, a diesel fuel spill on a grassland soil was simulated under pot conditions at a dose of 12,000 mg diesel kg{sup -1} DW soil. Thirty days after diesel addition, T. repens (white clover) and L. perenne (perennial ryegrass) were sown in the pots and grown under greenhouse conditions (temperature 25/18 {sup o}C day/night, relative humidity 60/80% day/night and a photosynthetic photon flux density of 400 {mu}mol photon m{sup -2} s{sup -1}) for 5 months. A parallel set of unplanted pots was also included. Concentrations of n-alkanes in soil were determined as an indicator of diesel degradation. Seedling germination, plant growth, maximal photochemical efficiency of photosystem II (F{sub v}/F{sub m}), pigment composition and lipophylic antioxidant content were determined to assess the impacts of diesel on the studied plants. Soil microbial community characteristics, such as enzyme and community-level physiological profiles, were also determined and used to calculate the soil quality index (SQI). The presence of plants had a stimulatory effect on soil microbial activity. L. perenne was far more tolerant to diesel contamination than T. repens. Diesel contamination affected soil microbial characteristics, although its impact was less pronounced in the rhizosphere of L. perenne. Rhizoremediation with T. repens and L. perenne resulted in a similar reduction of total n-alkanes concentration. However, values of the soil microbial parameters and the SQI showed that the more tolerant species (L. perenne) was able to better maintain its rhizosphere characteristics when growing in diesel-contaminated soil, suggesting a better soil health. We concluded that plant tolerance is of

  13. Measurement and characteristics of microbial biomass in forest soils

    International Nuclear Information System (INIS)

    Vance, E.D.

    1986-01-01

    The soil microbial biomass is the primary agent responsible for the breakdown and mineralization of soil organic matter and plays a major role in regulating nutrient availability to plants. In this study, methods for measuring biomass in soil were compared and tested in forest soils ranging in pH from 3.2 to 7.2. A good relationship between biomass C measured using the chloroform fumigation-incubation method and soil ATP or microbial biomass C by direct microscopy was found in soils at or above pH 4.2. The fumigation-incubation method consistently underestimated biomass C in soils below pH 4.2, however. Hypotheses for the breakdown of the fumigation-incubation method in strongly acid soils were tested by using an alterative fumigant, measuring the proportion of added 14 C labelled fungi and bacteria decomposed in fumigated soils (k/sub C/), and by studying the effect of large, non-fumigated soil inocula on the flush of respiration following fumigation. These studies indicated that the failure of the method in strongly acid soils was due to inhibited decomposition of non-microbial soil organic matter by the microbial recolonizing population following fumigation. A modified method for measuring biomass C by fumigation-incubation in acid soils is proposed

  14. BOREAS TF-01 SSA-OA Soil Characteristics Data

    Data.gov (United States)

    National Aeronautics and Space Administration — ABSTRACT: Data collected in support of the effort to characterize and interpret soil information at the SSA-OA tower site in 1994. Data collected include soil...

  15. BOREAS TF-01 SSA-OA Soil Characteristics Data

    Data.gov (United States)

    National Aeronautics and Space Administration — Data collected in support of the effort to characterize and interpret soil information at the SSA-OA tower site in 1994. Data collected include soil respiration,...

  16. Effects of soil amendment on soil characteristics and maize yield in Horqin Sandy Land

    Science.gov (United States)

    Zhou, L.; Liu, J. H.; Zhao, B. P.; Xue, A.; Hao, G. C.

    2016-08-01

    A 4-year experiment was conducted to investigate the inter-annual effects of sandy soil amendment on maize yield, soil water storage and soil enzymatic activities in sandy soil in Northeast China in 2010 to 2014. We applied the sandy soil amendment in different year, and investigated the different effects of sandy soil amendment in 2014. There were six treatments including: (1) no sandy soil amendment application (CK); (2) one year after applying sandy soil amendment (T1); (3) two years after applying sandy soil amendment(T2); (4) three years after applying sandy soil amendment(T3); (5)four years after applying sandy soil amendment(T4); (6) five years after applying sandy soil amendment (T5). T refers to treatment, and the number refers to the year after application of the sandy soil amendment. Comparing with CK, sandy soil amendments improved the soil water storage, soil urease, invertase, and catalase activity in different growth stages and soil layers, the order of soil water storage in all treatments roughly performed: T3 > T5 > T4 > T2 > T1 > CK. the order of soil urease, invertase, and catalase activity in all treatments roughly performed: T5 > T3 > T4 > T2 > T1 > CK. Soil application of sandy soil amendment significantly (p≤⃒0.05) increased the grain yield and biomass yield by 22.75%-41.42% and 29.92%-45.45% respectively, and maize yield gradually increased with the years go by in the following five years. Sandy soil amendment used in poor sandy soil had a positive effect on soil water storage, soil enzymatic activities and maize yield, after five years applied sandy soil amendment (T5) showed the best effects among all the treatments, and deserves further research.

  17. Characteristics and management options of crusting soils in a ...

    African Journals Online (AJOL)

    scheme include destruction of soil structure by heavy tillage implements prior to resettlement, low soil organic carbon input practices and high-intensity rain storms (Bronick and. Lal 2005). The objectives of this study were therefore to. (1) assess the nature and distribution of the crusting soils at the scheme and (2) determine ...

  18. Characteristics and management options of crusting soils in a ...

    African Journals Online (AJOL)

    ... to control the crusting. The relationship between crust thickness and soil physical and chemical properties and management practices were assessed using stepwise regression analysis. Soil crusting was largely related to soil aggregation, infiltration, fine sand fraction, cotton monocropping and crop residue incorporation.

  19. compressibility characteristics of compacted black cotton soil treated

    African Journals Online (AJOL)

    eobe

    soil and also render the soils less plastic. In line with that, developing a ... enhance the usage of the material in geotechnical engineering works. ..... is probably attained; concomitantly the compressibility of soil diminishes. Okoro [36] also attributes the reduction to the replacement of fine clay particles with non- plastic fines.

  20. Horizontal variation in trace elements and soil characteristics at ...

    African Journals Online (AJOL)

    The aim of this study was to determine the horizontal variation in trace element concentrations and soil indicators in surface soil associated with the geothermal springs at Siloam and Tshipise. Results show that, in general, the trace element concentrations present in the soil decrease with horizontal distance from the ...

  1. Correlation of Cadmium Distribution Coefficients to Soil Characteristics

    DEFF Research Database (Denmark)

    Holm, Peter Engelund; Rootzen, Helle; Borggaard, Ole K.

    2003-01-01

    Cadmium (Cd) distribution between the soil solid phase and the soil solution is a key issue in assessing the environmental effect of Cd in the terrestrial environmental. Previous studies have shown that many individual minerals and other components found in soils can bind Cd, but most studies...

  2. Study on Characteristics of Soil Elements Bio-availability and Their Interrelationship in Black Soil Area of Jilin Province

    Science.gov (United States)

    Wang, D. Y.

    2015-12-01

    Abstract: Based on systematic field investigation and surface soil(0-20cm) sampling in the middle part of Jilin province where the soil type mainly consists of black soil and chernozem, soil total content and bio-available content of Fe, Fe, Ca, Mg, K, P, Cu, Zn, Ni, Cr, B, Cd, As were tested. This paper summarizes the geochemical characteristics of the soil elements and takes the ratio of bio-available content to total content as the bio-availability characteristic of each element in soil and studies the interrelationship between their geochemical characteristics of bio-availability by PCA and correlation analysis. Cd、Cr、Ni、Zn、P、Ca are selected out by PCA due to the similar impact under 4 principal components. And their correlation analysis results indicate: the correlation coefficients between heavy metal elements(Cr, Cd, Zn, Ni) bio-availability are significant positive, i.e., the same spatial variation trends are found between them in study area; the same relationships are also found between the bioavailability of P and 4 heavy metal elements (Cr, Cd, Zn, Ni), the promotion of the bioavailability of heavy metal elements goes with P; However, the correlation coefficients between heavy metal(Cr, Cd, Zn, Ni) bio-availability and Ca are mostly significant negative and the adverse spatial variation trends are found between them. The promotion of the bioavailability of heavy metal elements goes against Ca. Key words: soil geochemistry; soil heavy metals; elements interaction; bio-availability

  3. Spatial variation of corn canopy temperature as dependent upon soil texture and crop rooting characteristics

    Science.gov (United States)

    Choudhury, B. J.

    1983-01-01

    A soil plant atmosphere model for corn (Zea mays L.) together with the scaling theory for soil hydraulic heterogeneity are used to study the sensitivity of spatial variation of canopy temperature to field averaged soil texture and crop rooting characteristics. The soil plant atmosphere model explicitly solves a continuity equation for water flux resulting from root water uptake, changes in plant water storage and transpirational flux. Dynamical equations for root zone soil water potential and the plant water storage models the progressive drying of soil, and day time dehydration and night time hydration of the crop. The statistic of scaling parameter which describes the spatial variation of soil hydraulic conductivity and matric potential is assumed to be independent of soil texture class. The field averaged soil hydraulic characteristics are chosen to be representative of loamy sand and clay loam soils. Two rooting characteristics are chosen, one shallow and the other deep rooted. The simulation shows that the range of canopy temperatures in the clayey soil is less than 1K, but for the sandy soil the range is about 2.5 and 5.0 K, respectively, for the shallow and deep rooted crops.

  4. The characteristics of soil and water loss in Pinus Massoniana forest in Quaternary red soil area of south China

    Science.gov (United States)

    Song, Yuejun; Huang, Yanhe; Jie, Yang

    2017-08-01

    The soil and water loss in Pinus massoniana forests is an urgent environmental problem in the red soil region of southern China.Using the method of field monitoring, by analogy and statistical analysis, The characteristics of soil and water loss of Pinus massoniana forests in Quaternary red soil region under 30 rainfall were analyzed,the results show that the relationship models of rainfall,runoff and sediment of pure Pinus massoniana plot were slightly different from the naked control plot,were all the univariate quadratic linear regression models.the contribution of runoff and sediment in different rain types were different, and the water and soil loss in Pinus massoniana forest was most prominent under moderate rain.The merging effect of sparse Pinus massoniana forest on raindrop, aggravated the degree of soil and water loss to some extent.

  5. [Spatial characteristics of soil organic carbon and nitrogen storages in Songnen Plain maize belt].

    Science.gov (United States)

    Zhang, Chun-Hua; Wang, Zong-Ming; Ren, Chun-Ying; Song, Kai-Shan; Zhang, Bai; Liu, Dian-Wei

    2010-03-01

    By using the data of 382 typical soil profiles from the second soil survey at national and county levels, and in combining with 1:500000 digital soil maps, a spatial database of soil profiles was established. Based on this, the one meter depth soil organic carbon and nitrogen storage in Songnen Plain maize belt of China was estimated, with the spatial characteristics of the soil organic carbon and nitrogen densities as well as the relationships between the soil organic carbon and nitrogen densities and the soil types and land use types analyzed. The soil organic carbon and nitrogen storage in the maize belt was (163.12 +/- 26.48) Tg and (9.53 +/- 1.75) Tg, respectively, mainly concentrated in meadow soil, chernozem, and black soil. The soil organic carbon and nitrogen densities were 5.51-25.25 and 0.37-0.80 kg x m(-2), respectively, and the C/N ratio was about 7.90 -12.67. The eastern and northern parts of the belt had much higher carbon and nitrogen densities than the other parts of the belt, and upland soils had the highest organic carbon density [(19.07 +/- 2.44) kg x m(-2)], forest soils had the highest nitrogen density [(0.82 +/- 0.25) kg x m(-2)], while lowland soils had the lower organic carbon and nitrogen densities.

  6. Effects of Near Soil Surface Characteristics on the Soil Detachment Process in a Chronological Series of Vegetation Restoration

    Science.gov (United States)

    Wang, Bing

    2017-04-01

    The effects of near soil surface characteristics on the soil detachment process might be different at different stages of vegetation restoration. This study was performed to investigate the effects of the near soil surface factors of plant litter, biological soil crusts (BSCs), dead roots and live roots on the soil detachment process by overland flow at different stages of restoration. Soil samples (1 m long, 0.1 m wide, and 0.05 m high) under four treatment conditions were collected from 1-yr-old and 24-yr-old natural grasslands and subjected to flow scouring under five different shear stresses ranging from 5.3 to 14.6 Pa. The results indicated that the effects of near soil surface characteristics on soil detachment were substantial during the process of vegetation restoration. The total reduction in the soil detachment capacity of the 1-yr-old grassland was 98.1%, and of this total, 7.9%, 30.0% and 60.2% was attributed to the litter, BSCs and plant roots, respectively. In the 24-yr-old grassland, the soil detachment capacity decreased by 99.0%, of which 13.2%, 23.5% and 62.3% was caused by the litter, BSCs and plant roots, respectively. Combined with the previously published data of a 7-yr-old grassland, the influence of plant litter on soil detachment was demonstrated to increase with restoration time, but soil detachment was also affected by the litter type and composition. The role of BSCs was greater than that of plant litter in reducing soil detachment during the early stages of vegetation recovery. However, its contribution weakened with time since restoration. The influence of plant roots accounted for at least half or up to two-thirds of the total near soil surface factors, of which more than 72.6% was attributed to the physical binding effects of the roots. The chemical bonding effect of the roots increased with time since restoration and was greater than the effect of the litter on soil detachment in the late stages of vegetation restoration. The

  7. Characteristics and Classification of Soils Developed Over Coastal ...

    African Journals Online (AJOL)

    A semi-detailed soil survey of the land of Ikwuano Local Government Area Abia State South East Nigeria was made with the aid of the digitized map. Pedons in the identified mapping units were sampled and studied for their morphology, physical and chemical properties (e.g. soil colour, texture, pH, CEC, %OC, base ...

  8. Chemical, physical and biological characteristics of urban soils. Chapter 7

    Science.gov (United States)

    Richard V. Pouyat; Katalin Szlavecz; Ian D. Yesilonis; Peter M. Groffman; Kirsten. Schwarz

    2010-01-01

    Urban soils provide an array of ecosystem services to inhabitants of cities and towns. Urbanization affects soils and their capacity to provide ecosystem services directly through disturbance and management (e.g., irrigation) and indirectly through changes in the environment (e.g., heat island effect and pollution). Both direct and indirect effects contribute to form a...

  9. Characteristics and Classification of Soils on Quaternary Coversand ...

    African Journals Online (AJOL)

    Astudy was conducted to characterize and classify the soils on quaternary parent materials (Sangiwa, Sokoto, and Illela coversand) of Sokoto-Rima river basin area of Sokoto state. Areas covered with the coversand were identified using geologic map of the Sokoto-Rima basin followed by ground truthing. Soils from different ...

  10. Vegetation and Soil Characteristics in SIR-C data

    NARCIS (Netherlands)

    Broek, A.C. van den; Rijckenberg, G.J.; Davidson, M.; Freeman, A.

    1995-01-01

    We compared polarimetric C- and L-band and ground truth data from bare soil, young wheat and mature maize fields of the agricultural test site Flevoland in the Netherlands collected during the SIR-C campaign in April and October 1994. We find that the L-band is more sensitive to the soil roughness

  11. Characteristics and classification of soils of Gora Daget forest, South ...

    African Journals Online (AJOL)

    As a result there are few sites where undisturbed soils exist for use as a reference against which the impacts of land use can be evaluated. The Gora Daget forest on a very steep slope located close to Dessie town provides one of these rare opportunities for the type of investigation. Three pairs of representative soil profiles ...

  12. Soil Carbon Characteristics of a Fluvisol Affected by Aggregates ...

    African Journals Online (AJOL)

    Michael Horsfall

    105 – 111. Blom, L.and Eddhausen, L. (1985). Direct titration of carbon dioxide. Analytical Chemistry 13: 120 –. 128. Boyle, M., and Paul, E. A. (1989). Carbon and nitrogen kinetics in soil prevcously amended with sewage sludge. Soil Science Society America. Journal 53:99 – 103. Cambardella, C. A.and Elliott, E. T. (1992).

  13. Soil water characteristics of Middle Pleistocene paleosol layers on ...

    African Journals Online (AJOL)

    Soil water plays an important role in water quality monitoring, irrigation scheduling, solute migration, and plant growth. ... Information about the soil hydraulic properties of Middle Pleistocene paleosol layers within the Yingpan section on the Loess Plateau of China is necessary since it may affect water cycle processes both ...

  14. Characteristics and management options of crusting soils in a ...

    African Journals Online (AJOL)

    agriculture is practised (Nyamapfene and Hungwe 1986). Farmers experience considerable economic losses due to poor establishment of small-seeded crops, e.g. cotton. (Gossypium hirsutum) and soybean (Glycine max), reduced water infiltration and accelerated soil erosion resulting from soil crusting (Borseli et al. 1996 ...

  15. Effects of some physical and chemical characteristics of soil on ...

    African Journals Online (AJOL)

    ELO

    number of seeds per pod, number of pod per plant, grain yield, pod yield and weight of ... poor productivity. Several factors related to soil fertility limit agricultural production. Many factors such as soil type, farmer's practices, crop residues and ...

  16. Soil classification using mid-infrared off-normal active differential reflectance characteristics

    International Nuclear Information System (INIS)

    Narayanan, R.M.; Green, S.E.; Alexander, D.R.

    1992-01-01

    Active mid-infrared laser reflectance characteristics of 18 different bench-mark soil samples were measured at various angles of incidence between 0° and 80° at 9.283-, 10/247-, and 10.633-μm wavelengths for both copolarized and cross-polarized conditions. Calibration was performed for each measurement using a Labsphere Infragold diffuse reflectance standard of 94 percent reflectance. One hundred independent reflectivity measurements were averaged for each combination to yield a mean reflectance value. The soil samples were characterized in terms of the soil taxonomy, mineralogy, geographic location, soil texture, and organic carbon content. Selected samples represented wide variability in soil properties

  17. Dynamic characteristics of soil respiration in Yellow River Delta wetlands, China

    Science.gov (United States)

    Wang, Xiao; Luo, Xianxiang; Jia, Hongli; Zheng, Hao

    2018-02-01

    The stable soil carbon (C) pool in coastal wetlands, referred to as "blue C", which has been extensively damaged by climate change and soil degradation, is of importance to maintain global C cycle. Therefore, to investigate the dynamic characteristics of soil respiration rate and evaluate C budgets in coastal wetlands are urgently. In this study, the diurnal and seasonal variation of soil respiration rate in the reed wetland land (RL) and the bare wetland land (BL) was measured in situ with the dynamic gas-infrared CO2 method in four seasons, and the factors impacted on the dynamic characteristics of soil respiration were investigated. The results showed that the diurnal variation of soil respiration rate consistently presented a "U" curve pattern in April, July, and September, with the maximum values at 12:00 a.m. and the minimum values at 6:00 a.m. In the same season, the diurnal soil respiration rate in RL was significantly greater than those in BL (P soil respiration rate was 0.14, 0.42, and 0.39 μmol m-2 s-1 in RL, 0.05, 0.22, 0.13, and 0.01 μmol m-2 s-1 in BL, respectively. Soil surface temperature was the primary factor that influenced soil respiration, which was confirmed by the exponential positive correlation between the soil respiration rate and soil surface temperature in BL and RL (P salinity of soils suppressed soil respiration, confirming by the significantly negative correlation between soil respiration rate and the content of soluble salt. These results will be useful for understanding the mechanisms underlying soil respiration and elevating C sequestration potential in the coastal wetlands.

  18. Thermokarst dynamics and soil organic matter characteristics controlling initial carbon release from permafrost soils in the Siberian Yedoma region

    DEFF Research Database (Denmark)

    Weiss, Niels; Blok, Daan; Elberling, Bo

    2016-01-01

    This study relates soil organic matter (SOM) characteristics to initial soil incubation carbon release from upper permafrost samples in Yedoma region soils of northeastern Siberia, Russia. Carbon (C) and nitrogen (N) content, carbon to nitrogen ratios (C:N), δ13C and δ15N values show clear trends...... that correspond with SOM age and degree of decomposition. Incubation results indicate that older and more decomposed soil material shows higher C respiration rates per unit incubated C than younger and less decomposed samples with higher C content. This is important as undecomposed material is often assumed...... to be more reactive upon thawing. Large stocks of SOM and their potential decomposability, in combination with complex landscape dynamics that include one or more events of Holocene thaw in most of the landscape, are of consequence for potential greenhouse gas release from permafrost soils in the Yedoma...

  19. Experimental research on the structural characteristics of high organic soft soil in different deposition ages

    Science.gov (United States)

    Liu, Fei; Lin, Guo-he

    2018-03-01

    High organic soft soil, which is distributed at Ji Lin province in China, has been studied by a lot of scholars. In the paper, structural characteristics with different deposition ages have been researched by experimental tests. Firstly, the characteristics of deposition age, degree of decompositon, high-pressure consolidation and microstructure have been measured by a series of tests. Secondly, structural strengths which were deposited in different ages, have been carried out to test the significant differences of stress-strain relations between remoulded and undisturbed high organic soft soil samples. Results showed that high organic soft soil which is deposited at different ages will influence its structural characteristics.

  20. Noninvasive Monitoring of Soil Static Characteristics and Dynamic States

    DEFF Research Database (Denmark)

    Cassiani, Giorgio; Ursino, Nadia; Deiana, Rita

    2012-01-01

    that vegetation extracts a large amount of water from the soil particularly during summer, but it also reduces evaporation by shadowing the soil surface. Vegetation represents a screen for rainfall and prevents light rainfall infiltration but enhances the wetting process by facilitating the infiltration...... and the ground water recharge. In many cases, the vegetation creates a positive feedback system. In our study, these mechanisms are well highlighted by the use of noninvasive techniques that provide data at the scale and resolution necessary to understand the hydrological processes of the topsoil, also...... in their lateral and depth spatial variability. Unlike remote sensing techniques, noninvasive geophysics penetrates the soil subsurface and can effectively image moisture content in the root zone. We also developed a simple conceptual model capable of representing the vegetation–soil interaction with a simple...

  1. [Ecophysiological Characteristics of actinomycetes of desert soils of Mongolia].

    Science.gov (United States)

    Zenova, G M; Kozhevin, P A; Manucharova, N A; Lubsanova, D A; Dubrova, M S

    2014-01-01

    It is shown that the actinomycete complex in steppe-desert light brown salty soil of desert steppes of Mongolia is represented by the genera Streptomyces and Micromonospora. The species diversity of the genus Streptomyces, which dominates the complex, decreases with increasing osmolarity of the medium. The influence of environmental factors--temperature and osmolarity of medium--on the development of metabolically active members of the phylum Actinobacteria in the domain Bacteria of the prokaryotic microbial soil community was established. The proportion of metabolically active bacteria belonging to Actinobacteria increases with increasing osmolarity and incubation temperature of soil. The dominance of the filamentous metabolically active members of the phylum Actinobacteria over the unicellular organisms was shown. The halotolerant actinomycetes isolated from the steppe-desert soils were alkalotolerant, xerophilic, and thermotolerant and exhibited antimicrobial activity with respect to Gram-positive bacteria and actinomycetes.

  2. Soil-water repellency characteristic curves for soil profiles with organic carbon gradients

    DEFF Research Database (Denmark)

    Wijewardana, Nadeeka Senani; Müller, Karin; Møldrup, Per

    2016-01-01

    Highlights •Water repellency at different soil organic carbon (SOC) contents was measured. •Repellency was restricted to the top 20 cm of the soil profiles. •The sessile drop method is highly sensitive at high SOC contents. •We proposed six repellency parameters for repellent soils. •Functions...

  3. Characteristics of heavy metal pollution on roadside soil along highway

    Science.gov (United States)

    Zheng, Chaocheng

    2017-10-01

    Highway traffic is the main source of heavy metal pollution. Due to limited cropland, it is very common to plant crops along the highways. So, in view of agricultural products safety, heavy metal pollution by highway traffic to soils along highway is widely concerned. Therefore, to study distribution traits, accumulative laws and influence factors of heavy metals in agricultural soils could provide scientific evidence and theoretical basis for environmental protection along express way.

  4. [Characteristics of soil pH and exchangeable acidity in red soil profile under different vegetation types].

    Science.gov (United States)

    Ji, Gang; Xu, Ming-gang; Wen, Shi-lin; Wang, Bo-ren; Zhang, Lu; Liu, Li-sheng

    2015-09-01

    The characteristics of soil pH and exchangeable acidity in soil profile under different vegetation types were studied in hilly red soil regions of southern Hunan Province, China. The soil samples from red soil profiles within 0-100 cm depth at fertilized plots and unfertilized plots were collected and analyzed to understand the profile distribution of soil pH and exchangeable acidity. The results showed that, pH in 0-60 cm soil from the fertilized plots decreased as the following sequence: citrus orchard > Arachis hypogaea field > tea garden. As for exchangeable acidity content, the sequence was A. hypogaea field ≤ citrus orchard pH decreased by 0.55 and 0.17 respectively, but such changes did not occur in citrus orchard. Soil pH in 0-40 cm soil from the natural recovery vegetation unfertilized plots decreased as the following sequence: Imperata cylindrica land > Castanea mollissima garden > Pinus elliottii forest ≥ Loropetalum chinensis forest. As for exchangeable acidity content, the sequence was L cylindrica land pH in surface soil (0-20 cm) from natural forest plots, secondary forest and Camellia oleifera forest were significantly lower than that from P. massoniana forest, decreased by 0.34 and 0.20 respectively. For exchangeable acidity content in 0-20 cm soil from natural forest plot, P. massoniana forest and secondary forest were significantly lower than C. oleifera forest. Compared with bare land, surface soil acidification in unfertilized plots except I. cylindrica land had been accelerated, and the natural secondary forest was the most serious among them, with surface soil pH decreasing by 0.52. However, the pH increased in deep soils from unfertilized plots except natural secondary forest, and I. cylindrica land was the most obvious among them, with soil pH increasing by 0.43. The effects of fertilization and vegetation type on pH and exchangeable acidity decreased with the increasing soil depth from all plots.

  5. Time-dependent physicochemical characteristics of Malaysian residual soil stabilized with magnesium chloride solution

    OpenAIRE

    Latifi, Nima; Rashid, Ahmad Safuan A.; Ecemiş, Nurhan; Tahir, Mahmood Md; Marto, Aminaton

    2016-01-01

    The effects of non-traditional additives on the geotechnical properties of tropical soils have been the subject of investigation in recent years. This study investigates the strength development and micro-structural characteristics of tropical residual soil stabilized with magnesium chloride (MgCl2) solution. Unconfined compression strength (UCS) and standard direct shear tests were used to assess the strength and shear properties of the stabilized soil. In addition, the micro-structural char...

  6. Effect of flaming on wild mustard (Sinapis arvensis L. soil seed bank, soil micro organisms and physicochemical characteristics

    Directory of Open Access Journals (Sweden)

    H. Salimi

    2016-05-01

    Full Text Available In order to study the effect of flaming on seed viability of Sinapis arvensis L., changes in microorganisms population and physicochemical characteristics of soil after canola (Brassica napus L. harvesting, an experiment was carried out based on randomized complete block design with four replications and eight treatments at Karaj Research Center, Iran, during 2005- 2006. After harvesting canola at the end of spring, wild mustard seeds were distributed evenly on the surface of the soil. In some plots, canola stubbles were left on the ground and in some plots canola stubbles were taken off. Under this condition, the following treatments were applied: Flaming under wet and dry soil condition, burning stubbles under wet and dry soil condition. In other plots canola stubbles were taken off the plots and then flaming was applied under wet and dry soil conditions. Check plots did not receive any treatment. Results indicated that all treatments reduced seed viability, and the highest loss in seedling density occurred in the flaming treatment on dry-soil. Flaming did not have any serious affect on soil microorganisms or on its other physiochemical aspects, however dry-soil treatments proved the safest.

  7. Estimation of heavy metal-contaminated soils' mechanical characteristics using electrical resistivity.

    Science.gov (United States)

    Chu, Ya; Liu, Songyu; Wang, Fei; Cai, Guojun; Bian, Hanliang

    2017-05-01

    Under the process of urbanization in China, more and more attention has been paid to the reuse of heavy metal-contaminated sites. The shear characteristics of heavy metal-contaminated soils are investigated by electrical detection in this paper. Three metal ions (Zn 2+ , Cd 2+ , and Pb 2+ ) were used, the metal concentrations of which are 50, 166.67, 500, 1666.67, and 5000 mg/kg, respectively. Direct shear tests were used to investigate the influence of heavy metal ions on the shear characters of soil samples. It is found that with the addition of heavy metal ions, the shear strength, cohesion, and friction angle of contaminated soils are higher than the control samples. The higher concentration of heavy metal ions penetrated in soils, the higher these engineering characteristics of contaminated soils observed. In addition, an electrical resistivity detection machine is used to evaluate the shear characteristics of contaminated soils. The electrical resistivity test results show that there is a decreasing tendency of resistivity with the increase of heavy metal ion concentrations in soils. Compared with the electrical resistivity and the shear characteristics of metal-contaminated soils, it is found that, under fixed compactness and saturation, shear strength of metal-contaminated soils decreased with the increase of resistivity. A basic linear relationship between C/log(N + 10) and resistivity can be observed, and there is a basic linear relationship between φ/log(N + 10) and resistivity. Besides, a comparison of the measured and predicted shear characteristics shows a high accuracy, indicating that the resistivity can be used to evaluate the shear characteristics of heavy metal contaminated soils.

  8. Phosphorus adsorption parameters in relation to soil characteristics

    International Nuclear Information System (INIS)

    Mehmood, A.; Akther, M.S.; Hayat, R.; Memon, M.

    2010-01-01

    Understanding of soil phosphorus (P) adsorption chemistry is essential for evolving best fertilizer management practices aimed at enhancing fertilizer P use efficiency and environment quality. Soil chemical parameters which govern P adsorption maxima and binding strength in calcareous and non-calcareous soils were determined. Five soils representing three different parent materials i.e. mixed mineralogy alluvium, loess and non calcareous sandstone were sampled at genetic horizons in each profile. Phosphorus adsorption isotherm was developed for each of the 32 soil samples by equilibration of two g air dry soil with 0 to 4000 mgl/sup -1/ (0 to 125 mM) P in 20 ml of 10 mM KCI; and fitted to Langmuir and Freundlich equations. The chemical parameters i.e. pH, CaCO/sub 3/, total and dissolved organic carbon, exchangeable calcium, dithionite extractable iron (Fe/sub d/) and aluminum (AI/sub d/), oxalate extractable iron (Fe/sub o/) and aluminum (Al/sub o/) and as a test for plant available P extractable with NaHCO/sub 3/ were determined. The Fruendlich equation, an empirical relation between adsorbed and solution P, fitted the adsorption isotherms better than the Langmuir equation which relates adsorption to solid surface coverage by adsorbate. Adsorption maxima at low affinity sites positively correlated with soil CaCO/sub 3/ due to precipitation as Ca-P and to extractable iron oxide; and the binding strength of high affinity (kJ sites correlated positively with soil Fe/sub d/, Al/sub o/, AI/sub d/, and crystalline iron oxide (Fe/sub d/-Fe/sub o/) contents. The Freundlich parameter b/sub r/, adsorption exponent which signifies sorption intensity also positively correlated with soil Fe/sub d/, Fe/sub cr/ and Aid contents. Phosphorus adsorption at its low concentration in equilibrium solution seems to be governed by soil iron oxides and precipitation as Ca-P is important only at high P concentration, less frequently achieved in farm fields. (author)

  9. Adsorption and desorption characteristics of lindane, carbofuran and methyl parathion on various Indian soils

    Energy Technology Data Exchange (ETDEWEB)

    Rama Krishna, K. [Department of Civil Engineering, Indian Institute of Technology Madras, Chennai 600036 (India)], E-mail: ramakrishnaiitm@gmail.com; Philip, Ligy [Department of Civil Engineering, Indian Institute of Technology Madras, Chennai 600036 (India)], E-mail: ligy@iitm.ac.in

    2008-12-30

    Adsorption and desorption characteristics of three insecticides on four Indian soils were studied. Insecticides used were representative of organochlorine, organophosphate, and carbomate groups. The order of adsorption of pesticides on soils was: lindane > methyl parathion > carbofuran. Compost soil had shown the maximum adsorption capacity. The order of adsorption capacity of various soils were: compost soil > clayey soil > red soil > sandy soil. Adsorption isotherms were better fitted to Freundlich model and K{sub f} values increased with increase in organic matter content of the soils. Thermodynamic parameters indicated favorable adsorption of all the three pesticides in four different soils. Adsorption was exothermic in nature. Distilled water desorbed 30-60% of adsorbed pesticides whereas; organic solvents were able to affect 50-80% of sorbed pesticides. Clay content and organic matter played a significant role in pesticide adsorption and desorption processes. Hysteresis effect was observed in red, clayey and compost soils. Hysteresis effect increased with increase in organic matter and clay content of the soils.

  10. Studies on soil and water characteristics of Burrow pits for possible ...

    African Journals Online (AJOL)

    Studies on soil and water characteristics of Burrow pits for possible conversion into fish ponds in Niger Delta, Nigeria. ... Soil and water parameters were investigated in 34 burrow pits in Egiland, Rivers State, in the Niger Delta region of Nigeria. The pits surface areas and depths ranged from 30,000 to 40,000 m2 and 1.00 to ...

  11. Soil hydraulic characteristics and its influence on the design of soak ...

    African Journals Online (AJOL)

    The hydraulic characteristics of the soil profile in a plot of land designated for a residential purpose were studied to obtain dependable data for the design of efficient septic- soak-away system in the estate. In situ infiltration tests on three horizons above 400 cm depth were conducted, and soil samples taken from the same ...

  12. [Fluorine speciation and its distribution characteristics in selected agricultural soils of North China Plain].

    Science.gov (United States)

    Yi, Chun-Yao; Wang, Bing-Guo; Jin, Meng-Gui

    2013-08-01

    The objectives of this study were to study fluorine speciation and its distribution characteristics in the cultivated soils of wheat-corn fields at the typical areas, the North China Plain. The fluorine contents in cultivated soils and profile soils were measured by consecutive extraction. The results showed that the soil total fluorine (T-F) content at typical areas in the North China Plain ranged from 338.31 mg x kg(-1) to 781.67 mg x kg(-1), with a mean of 430.46 mg x kg(-1). The soil fluorine speciation with the highest content was Residual-Fluorine (Res-F), with a mean of 402.73 mg x kg(-1). The average content of Water soluble Fluorine (Ws-F) was 14.39 mg x kg(-1). The result indicated that the cultivated soil in the study area was at a relatively high fluoride pollution level, which may be harmful to human health and the ecological environment. The contents of Organic Fluorine (Or-F) and Fe/Mn Oxide-Fluorine (Fe/ Mn-F) were also quite high, with a mean of 8.90 mg x kg(-1) and 4.10 mg x kg(-1), respectively. The exchangeable fluorine (Ex-F) only had a very small amount of 0.33 mg x kg(-1). Soil Ws-F was positively correlated with soil pH and CEC, while it was negatively correlated with the percentage of soil clay. The content of soil Fe/Mn-F was positively correlated with soil pH, CEC and the sand grain content percentage, while it was negatively correlated with the clay grain content percentage. The soil pH value had the most significant influence on the water soluble fluorine (Ws-F) and Fe/Mn Oxide-Fluorine (Fe/Mn-F), and the soil CEC had the most significant influence on the soil total fluorine (T-F) and residual-Fluorine (Res-F) by stepwise regression analysis. In the soil profiles, the T-F content appeared as peaks and valleys representing the change of the soil lithology in the vadose zone. The Ws-F in the soil profiles mainly changed in the depth of 0-100 cm near the surface soil and was little influenced by the soil lithology. But it was strongly

  13. Phosphorus Equilibrium Characteristics for Soils in the Upper Eau Galle River Watershed, Wisconsin

    National Research Council Canada - National Science Library

    James, William F

    2006-01-01

    The purpose of this demonstration was to examine phosphorus adsorption-desorption and equilibrium characteristics for soils collected from different land use practices in the Upper Eau Galle River watershed (Wisconsin...

  14. Comparative mineralogical characteristics of red soils from South Bulgaria

    Directory of Open Access Journals (Sweden)

    Marlena Yaneva

    2015-01-01

    Full Text Available The present study aims to compare mineralogical composition of red soils, formed on marbles in South Bulgaria. We used mineralogical analysis of heavy and light mineral fraction in immersion under polarizing microscope and X-ray diffraction analysis of bulk sample and clay fraction. Three test polygons, located in South Bulgaria were examined: Petrovo, Nova Lovcha and Dobrostan, which are characterized with different latitude, altitude, and exposition. Three or more sites from each polygon were sampled and analyzed. The red soils are formed on white and gray calcite and calcite-dolomite marbles, impure silicate-rich marbles and only in one site – on marble breccias. We determined the following mineral phases in red soils: calcite, dolomite, quarts, and feldspars, mica, illite-type mica, illite, smectite, vermiculite-smectite, and kaolinite. Heavy minerals are represented by amphibole, titanite and epidote, and minor amounts of zircon, garnet, tourmaline, rutile, pyroxene, andalusite, kyanite, sillimanite and apatite. Opaque minerals are predominantly goethite and hematite. Plant tissue is abundant in light fraction from 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

  15. Detailed soil mapping and relationships between soil characteristics and tree growth in an alluvial plain (Lombardy, Italy)

    Science.gov (United States)

    Ferré, Chiara; Comolli, Roberto

    2015-04-01

    The study area is located in an abandoned meander of the Oglio river (southern Lombardy, Italy), with young soils of alluvial origin (Calcaric Fluvisols). During 2002, in an area covering 20 hectares, a tree plant for wood production was realized (oak, hornbeam, ash, alder, and walnut; poplar only in the first part of the growth cycle). Objective of the study was to verify the existence of correlations between tree growth and soil characteristics. In 2004, the soil was sampled at 126 points, according to a regular grid, taking the surface soil horizon (Ap). The collected soil samples were analyzed in laboratory, measuring pH in H2O and KCl, texture, total carbonates, soil organic C (SOC), available P (Olsen), and exchangeable K. The pH in H2O varies between 7.7 and 8.1; the pH in KCl varies between 7.2 and 7.7; the more frequent particle-size classes are loam and sandy loam; SOC varies between 0.4 and 1.1%; total carbonates from 23 to 45%; exchangeable K between 0.01 and 0.25 cmol(+) kg-1; available P between 1.2 and 16.8 mg kg-1. At a distance of 12 years, in 2014, diameters at breast height of all the trees (2513 in total) were measured and their height was estimated on the basis of empirical equations obtained for each species, in order to calculate the tree volume. Spatial variability of soil properties was evaluated and mapped using multivariate geostatistical techniques. The analyses revealed the presence of different scales of spatial variation: micro-scale, short range scale (about 80 m for texture) and long range scale (about 220 m for texture). The spatial pattern of most soil properties (mainly texture and total carbonates) was probably associated with fluvial depositional processes. To evaluate soil-plant relationships, soil characteristics were collocated into the plant data set by estimating specific soil properties at each individual tree location. Soil spatial variability was reflected by the differences in plant growth. Statistical analysis of the

  16. Physico-chemical characteristics of salt affected soils in Sindh Province

    International Nuclear Information System (INIS)

    Naqvi, R.R.; Khattak, M.I.

    2005-01-01

    Physico-chemical characteristics of 13 typical soil profiles obtained from the salt affected areas of the Sindh provinces were determined to characterize the salinity of these soils. The soils are available in texture and highly calcareous in nature. From salinity point of view, the problem was found to be two fold. The soils contained not only high amounts of water soluble salts, but at certain places specially in Khairpur District: the Na/sup +/ ions had also entered the clay complexes and pH values at some places were above 8.5. According to the US salinity laboratory classification, the soils come under saline and saline sodic groups. The nature of soluble salts and reclamation measures have been desorbed and disused. The soils are mostly well drained and easily reclaimable. A salient feature of these soils is that good amount of reclamation. The saline soils can be reclaimed simply by leaching and cropping while salient alkali soils poor to leaching should be treated with required amount of gypsum or sulphur. Nearly 30 to 35 % of the salt affected soils need gypsum treatment. It is also suggested that Bajri Barseem or Rice Barseem rotation may be followed during the reclamation of highly saline and saline alkali soils. Further these would be the requirement of an effective drainage system, which is essential to lower the salt content and water table depth, especially at places, where salinity and water logging both occur together. (author)

  17. Effects of soil management in vineyard on soil physical and chemical characteristics

    Directory of Open Access Journals (Sweden)

    Linares Rubén

    2014-01-01

    Full Text Available Cover crops in Mediterranean vineyards are scarcely used due to water competition between the cover crop and the grapevine; however, bare soil management through tillage or herbicides tends to have negative effects on the soil over time (organic matter decrease, soil structure and soil fertility degradation, compaction, etc. The objective of this study was to understand how soil management affects soil fertility, compaction and infiltration over time. To this end, two bare soil techniques were compared, tillage (TT and total herbicide (HT with two cover crops; annual cereal (CT and annual grass (AGT, established for 8 years. CT treatment showed the highest organic matter content, having the biggest amount of biomass incorporated into the soil. The annual adventitious vegetation in TT treatment (568 kg dry matter ha-1 that was incorporated into the soil, kept the organic matter content higher than HT levels and close to AGT level, in spite of the greater aboveground annual biomass production of this treatment (3632 kg dry matter ha-1 whereas only its roots were incorporated into the soil. TT presented the highest bulk density under the tractor track lines and a greatest resistance to penetration (at 0.2 m depth. AGT presented bulk density values (upper 0.4 m lower than TT and penetration resistance in CT lower (at 0.20 m depth than TT too. The HT decreased water infiltration due to a superficial crust generated for this treatment. These results indicate that the use of annual grass cover can be a good choice of soil management in Mediterranean climate due to soil quality improvement, with low competition and simple management.

  18. Soil water characteristics of Middle Pleistocene paleosol layers on ...

    African Journals Online (AJOL)

    Administrator

    2011-09-14

    Sep 14, 2011 ... to hold water and this was related to their soil structures and porosities. These differences could be due to the different conditions prevailing during their formation. Although, paleosols occur at various depths, certain deep-rooting plants can access the water they hold. Therefore, the SWCC of the individual ...

  19. Improvement of strength characteristics of lateritic sub-grade soil ...

    African Journals Online (AJOL)

    Shredded high density polyethylene High Density Polyethylene Waste of maximum size 20 × 25mm was used for the improvement of lateritic soil at various percentages which are; 1%, 2%, 3%, 4%, and 5% respectively. Series of laboratory tests such as, Compaction and California Bearing Ratio (CBR) were conducted to ...

  20. Microbial characteristics of soils on a latitudinal transect in Siberia

    Czech Academy of Sciences Publication Activity Database

    Šantrůčková, Hana; Bird, M. I.; Kalaschnikov, Y. N.; Grund, M.; Elhottová, Dana; Šimek, Miloslav; Grigoryev, S.; Gleixner, G.; Arneth, A.; Schulze, E.D.; Lloyd, J.

    2003-01-01

    Roč. 9, - (2003), s. 1106-1117 ISSN 1354-1013 R&D Projects: GA ČR GA526/99/P033 Institutional research plan: CEZ:AV0Z6066911 Keywords : latitudial transect * microbial net growth rate * soil microbial activity Subject RIV: EH - Ecology, Behaviour Impact factor: 4.152, year: 2003

  1. Soil and Groundwater Characteristics of a Legacy Spill Site | Adoki ...

    African Journals Online (AJOL)

    The soil and groundwater of a legacy spill site in Eleme Local Government Authority Area of Rivers Stae were investigated. The general land use of the area within 1500m radius of the spill site is devoted to farming, fishing and hunting. The main crops grown include yams, cassava, maize, sugarcane, plantain, banana, ...

  2. Soil and Groundwater Characteristics of a Legacy Spill Site AKURO ...

    African Journals Online (AJOL)

    MICHAEL HORSFALL

    ABSTACT: The soil and groundwater of a legacy spill site in Eleme Local Government Authority Area of. Rivers Stae were investigated. The general land use of the area within 1500m radius of the spill site is devoted to farming, fishing and hunting. The main crops grown include yams, cassava, maize, sugarcane, plantain,.

  3. Soil pipe flow tracer experiments: 1. Connectivity and transport characteristics

    Science.gov (United States)

    Much debate has occurred in catchment hydrology regarding the connectivity of flow paths from upslope areas to catchment outlets. This study was conducted in two catchments, one with three upper branches, in a loess soil with a fragipan that fosters lateral flow and exhibits an extensive distributio...

  4. Soil Characteristics Around Lake Opi In Eastern Nigeria And Land ...

    African Journals Online (AJOL)

    The soils around the lake (@500-m radius) were sampled at 10-m intervals at approximately three concentric transects around the lake for preliminary information on consistence, texture and colour using auger samples. Based on the information obtained, 5 representative profiles were dug, 3 at @7 m from the lake and 2 at ...

  5. Prediction of characteristics of coastal plain soils using terrain ...

    African Journals Online (AJOL)

    Soil properties determined include depth, sand, silt, clay, electrical and hydraulic conductivity, bulk density, pH, exchangeable calcium, magnesium, sodium, potassium and acidity, available phosphorus, organic carbon, base saturation, crystalline and amorphous iron and aluminium oxides. The terrain attributes derived ...

  6. Physicochemical characteristics and heavy metal levels in soil ...

    African Journals Online (AJOL)

    Distribution pattern of heavy metals in petrol stations, abattoirs, mechanic workshops and hospital incinerator sites were Mn > Zn > Pb > Cd, while for dumpsites Zn > Mn > Pb > Cd. Pollution index indicated that soil qualities varied between slightly contaminated to severely polluted status. This showed that the heavy metal ...

  7. morphological characteristics and classification of soils derived from ...

    African Journals Online (AJOL)

    Prof. Ekwueme

    geology and geomorphology of South-Eastern Nigerian and. Cross River State. A total of six (6) profile pits (pedons) were excavated, two (2) in each of the three ..... soils can be classified as ustalfs at the sub-order level. Their occurrence under tropical climatic conditions permits their placement as Tropustaalfs in the Great ...

  8. Adsorption and desorption characteristics of endosulfan in two typical agricultural soils in Southwest China.

    Science.gov (United States)

    Qian, Sheng; Zhu, Heng; Xiong, Bailian; Zheng, Guocan; Zhang, Jinzhong; Xu, Weihong

    2017-04-01

    Endosulfan is an organochlorine pesticide widely used in Southwest China. In this paper, the adsorption and desorption characteristics of endosulfan in two typical agricultural soils (latosol and lateritic red soil) in this area were studied. The results showed that Langmuir isothermal equation could well describe the adsorption thermodynamic characteristics of endosulfan in latosol and lateritic red soil, and the maximum adsorption capacities of α-endosulfan were 0.186 and 0.209 mg/g, while those of β-endosulfan were 0.140 and 0.148 mg/g, respectively. Endosulfan adsorption in the two soils was an exothermic physicochemical process, but dominated by physical process. The adsorption kinetic characteristics of endosulfan in the two soils could be well described by second-order kinetic equation, and the initial rate constants were 0.228 and 0.325 mg/(g min) for α-endosulfan, while those were 0.119 and 0.125 mg/(g min) for β-endosulfan, respectively. The adsorbed endosulfan in the two soils was difficult to be desorbed into the liquid phase, and showed weak desorption hysteresis. These results implied that endosulfan could be firmly adsorbed by the two soils, and their adsorption and desorption abilities may be related to the contents of soil clay and organic matter.

  9. Structure stability and water retention near saturation characteristics as affected by soil texture, and polyacrylamide concentration

    Science.gov (United States)

    Mamedov, Amrakh I.; Ekberli, Imanverdi A.; Ozturk, Hasan S.; Wagner, Larry E.; Norton, Darrell L.; Levy, Guy J.

    2017-04-01

    Studying the effects of soil properties and amendment application on soil structure stability is important for the development of effective soil management and conservation practices for sustaining semi-arid soil and water quality under climate change scenarios. Two sets of experiments were conducted to evaluate the effects of soil texture and soil amendment polyacrylamide (PAM) rate on soil structural stability expressed in terms of near saturation soil water retention and aggregate stability using the high energy (0-5 J kg-1) moisture characteristic (HEMC) method. Contribution of (i) soil type were assessed using 30 soil samples varying in texture from sandy to clay taken from long term cultivated lands, covering a range of crop and land management practices, and (ii) anionic PAM concentration (0, 10, 25, 50, 100 & 200 mg l-1) were tested on selected loam and clay soils. The water retention curves of slow and fast wetted soil samples were characterized by a modified van Genuchten (1980) model that provides (i) model parameters α and n, which represent the location of the inflection point and the steepness of the S-shaped water retention curves, and (ii) a composite soil structure index (SI =VDP/MS; VDP-volume of drainable pores, MS-modal suction). The studied treatments had, generally, considerable effects on the shape of the water retention curves (α and n). Soil type, PAM concentration and their interaction had significantly effects on the stability indices (SI, VDP and MS) and the model parameters (α and n). The SI and α increased, and ndecreased exponentially with the increase in soil clay content and PAM concentration, but the shape of curves were soil texture and management dependent, since predominant changes were observed in the various range of studied macropores (pore size > 60 μm). An exponential type of relationship existed between SI and α and n. Effect of PAM contribution and wetting condition was more pronounced in the loam soil at low PAM

  10. Soil characteristics as criteria for cathodic protection of a nuclear fuel production facility

    International Nuclear Information System (INIS)

    Jenkins, C.F.; Corbett, R.A.

    1987-01-01

    The fact that buried metallic structures corrode is well documented. It has been postulated that the extent and rate of attack is controlled predominantly by the characteristics of the surrounding soil. Therefore, prior to constructing a new facility designed to process accumulated nuclear waste, consideration was given to protecting its underground pipelines against corrosion. Leak frequency curves from other nearby plantsites, extensive soil resistivity surveys, and geochemical analyses, were used to evaluate the onsite soil characteristics for corrosion susceptibility. Analysis of the data collected over a three-year period indicated that although the soil is not overly aggressive, substantial heterogeneity existed so as to establish galvanic cells along pipe lengths passing through the soil. To limit the extent of corrosion on underground piping, the application of an impressed current cathodic protection system was recommended to supplement a high integrity, corrosion resistant coating and wrap system

  11. Development of a Cone Penetrometer for Measuring Spectral Characteristics of Soils in Situ

    Science.gov (United States)

    Lee, Landris T., Jr.; Malone, Philip G.

    1993-01-01

    A patent was recently granted to the U.S. Army for an adaptation of a soil cone penetrometer that can be used to measure the spectral characteristics (fluorescence or reflectance) of soils adjacent to the penetrometer rod. The system can use a variety of light sources and spectral analytical equipment. A laser induced fluorescence measuring system has proven to be of immediate use in mapping the distribution of oil contaminated soil at waste disposal and oil storage areas. The fiber optic adaptation coupled with a cone penetrometer permits optical characteristics of the in-situ soil to be measured rapidly, safely, and inexpensively. The fiber optic cone penetrometer can be used to gather spectral data to a depth of approximately 25 to 30 m even in dense sands or stiff clays and can investigate 300 m of soil per day. Typical detection limits for oil contamination in sand is on the order of several hundred parts per million.

  12. A two stage data envelopment analysis model with undesirable output

    Science.gov (United States)

    Shariff Adli Aminuddin, Adam; Izzati Jaini, Nur; Mat Kasim, Maznah; Nawawi, Mohd Kamal Mohd

    2017-09-01

    The dependent relationship among the decision making units (DMU) is usually assumed to be non-existent in the development of Data Envelopment Analysis (DEA) model. The dependency can be represented by the multi-stage DEA model, where the outputs from the precedent stage will be the inputs for the latter stage. The multi-stage DEA model evaluate both the efficiency score for each stages and the overall efficiency of the whole process. The existing multi stage DEA models do not focus on the integration with the undesirable output, in which the higher input will generate lower output unlike the normal desirable output. This research attempts to address the inclusion of such undesirable output and investigate the theoretical implication and potential application towards the development of multi-stage DEA model.

  13. A Case of Undesired Bleb Developed After Penetrating Injury

    Directory of Open Access Journals (Sweden)

    Cem Ozgonul

    2014-03-01

    Full Text Available Eighty-year-old male patient was admitted to our policlinic with stinging, burning and itching in both eyes. Ophthalmological examination revealed avascular undesired bleb that releated with anterior chamber at 2-3 hour quadrant nasal limbus with the surrounding corneal and conjunctival epithelium was vascularized and the dimension was 3x3x3 mm. Towards these findings, we questioned the patient again and we found that, 40 years ago, a broken part of the shaving razor had injured his eye. After penetrating injury of the eye, because of the sutured wound leakage, undesired bleb formations can be seen. We suggest that kind of patient shold be followed up to prevent late complications of penetrating injury.

  14. Multifractal characteristics of Nitrogen adsorption isotherms from tropical soils

    Science.gov (United States)

    Vidal Vázquez, Eva; Paz Ferreiro, Jorge

    2010-05-01

    One of the primary methods used to characterize a wide range of porous materials, including soils, are gas adsorption isotherms. An adsorption isotherm is a function relating the amount of adsorbed gas or vapour to the respective equilibrium pressure, during pressure increase at constant temperature. Adsorption data allow easily estimates of specific surface area and also can provide a characterization of pore surface heterogeneity. Most of the properties and the reactivity of soil colloids are influenced by their specific surface area and by parameters describing the surface heterogeneity. For a restricted scale range, linearity between applied pressure and volume of adsorbate holds, which is the basis for current estimations of specific surface area. However, adsorption isotherms contain also non-linear segments of pressure versus volume so that evidence of multifractal scale has been demonstrated. The aim of this study was to analyze the multifractal behaviour of nitrogen adsorption isotherms from a set of tropical soils. Samples were collected form 54 horizons belonging to 19 soil profiles in the state of Minas Gerais, Brazil. The most frequent soil type was Oxisol, according to the Soil Survey Staff, equivalent to Latossolo in the Brazilian soil classification system. Nitrogen adsorption isotherms at standard 77 K were measured using a Thermo Finnigan Sorptomatic 1990 gas sorption analyzer (Thermo Scientific, Waltham, MA). From the raw data a distributions of mass along a support was obtained to perform multifractal analysis. The probability distribution was constructed by dividing the values of the measure in a given segment by the sum of the measure in the whole scale range. The box-counting method was employed to perform multifractal analysis. All the analyzed N2 adsorption isotherms behave like a multifractal system. The singularity spectra, f(α), showed asymmetric concave down parabolic shapes, with a greater tendency toward the left side, where moments

  15. Characteristics of biomass ashes from different materials and their ameliorative effects on acid soils.

    Science.gov (United States)

    Shi, Renyong; Li, Jiuyu; Jiang, Jun; Mehmood, Khalid; Liu, Yuan; Xu, Renkou; Qian, Wei

    2017-05-01

    The chemical characteristics, element contents, mineral compositions, and the ameliorative effects on acid soils of five biomass ashes from different materials were analyzed. The chemical properties of the ashes varied depending on the source biomass material. An increase in the concrete shuttering contents in the biomass materials led to higher alkalinity, and higher Ca and Mg levels in biomass ashes, which made them particularly good at ameliorating effects on soil acidity. However, heavy metal contents, such as Cr, Cu, and Zn in the ashes, were relatively high. The incorporation of all ashes increased soil pH, exchangeable base cations, and available phosphorus, but decreased soil exchangeable acidity. The application of the ashes from biomass materials with a high concrete shuttering content increased the soil available heavy metal contents. Therefore, the biomass ashes from wood and crop residues with low concrete contents were the better acid soil amendments. Copyright © 2016. Published by Elsevier B.V.

  16. Links between matrix bulk density, macropore characteristics and hydraulic behavior of soils

    DEFF Research Database (Denmark)

    Katuwal, Sheela; Møldrup, Per; Lamandé, Mathieu

    2013-01-01

    various macropore. In Silstrup soils, in which the macroporosity and matrix bulk density were well correlated, variation in air permeability and 5% tracer arrival time, a measure of preferential flow through soils, could be explained by macroporosity and the interconnectivity of macropores in soils....... However, in Faardrup soils macroporosity and matrix bulk density were weakly correlated. Though macroporosity and interconnectivity of macropores could explain some variation in the hydraulic behavior of a few samples from Faardrup, the preferential flow behavior was observed to be primarily influenced...... resolution X-ray CT and linked them with laboratory measurements of air permeability and leaching experiment. In addition to macropore characteristics, we also quantified the CT-number of the matrix as a measure of the bulk density of the matrix, i.e., excluding macropores in the soil. Soils from the two...

  17. [Experiment results of conduction, spectral induced polarization and dielectric characteristics for chrome-contaminated soil].

    Science.gov (United States)

    Nai, Chang-Xin; Liu, Yu-Qiang; Liu, Hao-Rui; Dong, Lu

    2011-03-01

    The resistivity, complex resistivity and complex permittivity of the chrome-contaminated soil were studied. Under the different pollution concentration and water content in the soil samples conditions, the relations between the resistivity, complex resistivity and complex permittivity of the chrome-contaminated soil and water content and the concentration of pollution were analyzed. When adding chrome pollution with different concentrations and water content, the experimental results show that the resistivity and complex resistivity of all the soil samples decreased with the pollution concentration and water content increased; but the phase of complex resistivity, which reflects the soil's capacitance, decreased below the 20 kHz and increase above the 20 kHz frequency. The real part and imaginary part of complex resostivity increased with the increase of pollution concentration and water content. The concentration of chrome pollutions and water content were the two main factor to determine the soil electrical characteristics.

  18. The role of curing period on the engineering characteristics of a cement-stabilized soil

    Directory of Open Access Journals (Sweden)

    Athanasopoulou Antonia

    2016-07-01

    Full Text Available Very often, pavements constructed in an economical manner or matching surface elevations of adjacent lanes cannot be designed for the soil conditions of the existing subgrade. Therefore, there is a need to stabilize the soil with an appropriate chemical substance in order to increase its strength to a satisfactory level. For the enhancement of subgrade soil strength characteristics, lime and cement are the most commonly used stabilizers. An experimental program was directed to the evaluation of a clayey soil and its mixtures with different cement contents performing tests on the index properties, the moisture-density relation, the unconfined compressive strength, and linear shrinkage. There is a definite improvement in strength. The time interval used to cure the prepared specimens affected positively both strength and plasticity features of the mixtures. A comparison with mixtures of the same soil with lime has been made, because of the wide use of lime in clay soil stabilization projects.

  19. The influence of vegetation and soil characteristics on active-layer thickness of permafrost soils in boreal forest.

    Science.gov (United States)

    Fisher, James P; Estop-Aragonés, Cristian; Thierry, Aaron; Charman, Dan J; Wolfe, Stephen A; Hartley, Iain P; Murton, Julian B; Williams, Mathew; Phoenix, Gareth K

    2016-09-01

    Carbon release from thawing permafrost soils could significantly exacerbate global warming as the active-layer deepens, exposing more carbon to decay. Plant community and soil properties provide a major control on this by influencing the maximum depth of thaw each summer (active-layer thickness; ALT), but a quantitative understanding of the relative importance of plant and soil characteristics, and their interactions in determine ALTs, is currently lacking. To address this, we undertook an extensive survey of multiple vegetation and edaphic characteristics and ALTs across multiple plots in four field sites within boreal forest in the discontinuous permafrost zone (NWT, Canada). Our sites included mature black spruce, burned black spruce and paper birch, allowing us to determine vegetation and edaphic drivers that emerge as the most important and broadly applicable across these key vegetation and disturbance gradients, as well as providing insight into site-specific differences. Across sites, the most important vegetation characteristics limiting thaw (shallower ALTs) were tree leaf area index (LAI), moss layer thickness and understory LAI in that order. Thicker soil organic layers also reduced ALTs, though were less influential than moss thickness. Surface moisture (0-6 cm) promoted increased ALTs, whereas deeper soil moisture (11-16 cm) acted to modify the impact of the vegetation, in particular increasing the importance of understory or tree canopy shading in reducing thaw. These direct and indirect effects of moisture indicate that future changes in precipitation and evapotranspiration may have large influences on ALTs. Our work also suggests that forest fires cause greater ALTs by simultaneously decreasing multiple ecosystem characteristics which otherwise protect permafrost. Given that vegetation and edaphic characteristics have such clear and large influences on ALTs, our data provide a key benchmark against which to evaluate process models used to predict

  20. Spectral reflectance and soil morphology characteristics of Santa Rita Experimental Range soils

    Science.gov (United States)

    A. Karim Batchily; Donald F. Post; R. B. Bryant; Donald J. Breckenfeld

    2003-01-01

    The Santa Rita Experimental Range (SRER) soils are mostly transported alluvial sediments that occur on the piedmont slope flanking the Santa Rita Mountains in Arizona. The major geomorphic land forms are alluvial fans or fan terraces, but there are also areas of residual soils formed on granite and limestone bedrock, basin floor, stream terraces, and flood plains. The...

  1. Physicochemical characteristics of the rhizosphere soils of some cereal crops in Ambo Woreda, West Shoa, Ethiopia

    Directory of Open Access Journals (Sweden)

    Louis E. Attah

    2010-03-01

    Full Text Available In this study, physicochemical properties of rhizosphere soils of some cereal crops in Ambo Woreda, West Shoa in Ethiopia have been investigated. Soil samples were collected from four different localities, viz. Awaro, Senkele, Meja and Guder, and their edaphic characteristics are determined. The soils are dominated by clay (40.4-45.8% along with coarse particles of sand. Bulk density, organic carbon (1.52-1.81% and electrical conductivity (1.3-1.9 dSm are low in all the soil samples. The soils are acidic with pH varying from 6.2 to 6.7. There are similarities in the relatively low content of available phosphorus (1.4-2.4 mg kg-1 and high available nitrogen content (480-986 mg kg-1 in all the soil samples while available potassium content (240-496 mg kg-1 is found to be medium in Awaro soil but high in the other three soil samples. Deficiencies are observed in the levels of available micro-nutrients (Cu: 1.2-1.8 µg g-1, Zn: 1.2-1.8 µg g-1 and Mn: 3.2-3.8 µg g-1 while the Fe content is sufficient in all the soil samples (340-496 µg g-1. With proper soil management, the farmlands studied are recommended for the cultivation of cereal crops.

  2. EFFECT OF REFINED PETROLEUM PRODUCTS CONTAMINATION ON BACTERIAL POPULATION AND PHYSICOCHEMICAL CHARACTERISTICS OF CULTIVATED AGRICULTURAL SOIL

    Directory of Open Access Journals (Sweden)

    Adewale Sogo Olalemi

    2012-10-01

    Full Text Available An investigation into the effect of refined petroleum products contamination on bacterial population and physicochemical characteristics of cultivated agricultural soil was carried out. The soil samples obtained from the Teaching and Research Farm, Obakekere, Federal University of Technology, Akure, Ondo State were contaminated with varying volumes of petrol, diesel and kerosene. The results revealed higher bacterial populations in uncontaminated soils than contaminated soils. The counts of bacteria ranged from 3.0 × 105 to 5.0 × 105 cfu/g in uncontaminated soils and 1.0 × 105 to 3.0 × 105 cfu/g in contaminated soils. The isolated bacteria were identified as Bacillus subtilis, Flavobacterium lutescens, Micrococcus luteus, Corynebacterium variabilis, Pseudomonas fluorescens. The contamination had no significant effect on pH, potassium, sodium, organic carbon and nitrogen content of the soils, while the moisture, calcium, phosphorus and magnesium content of the contaminated soils were significantly different (P < 0.05 compared with the uncontaminated soils. The ability of Bacillus subtilis, Flavobacterium lutescens, Micrococcus luteus, and Pseudomonas fluorescens to utilize the refined petroleum products suggest that these bacteria had potential to bioremediate petroleum contaminated soils.

  3. EVALUATION OF A SIMULATOR MODEL FOR PREDICTING SOIL-WATER CHARACTERISTICS OF SELECTED AGMCULTURAL FIELDS

    Directory of Open Access Journals (Sweden)

    H. E. Igbadun

    2011-06-01

    Full Text Available The ability of the Soil Water Characteribtics-Hydraulic Calculator (SWC-HPC model in predicting soi-water agricultural fields in Zaria, Nigeria, was tested and reprted in this study. The goal was to establish the predictability and reliability of the nodel, and hence, its use in determining water characteristics of soils in the stud/ area. Forty soil samples collected from four irrigation sites were used in the valuation. The soils particle size distribution (specifically, percent clay and sand and organic matter contents were inputted into the model to simulate soil moistur; status at saturation, field capacity and wilting point, soil bulk density and saturated hydraulic conductivity. The model outputs were statistically compared with observed parameters from laboratory tests using root mean square error (RMSE, c< ^efficient of variation (CV, modeling efficiency (EF and coefficient of residual mass (CRM. The model accurately simulated the observed bulk densities of the soil tested, satisfactorily simulated soil moisture content at field capacity, and mot lerately simulated moisture content at saturation and wilting point. The model lowever, poorly simulated saturated hydraulic conductivity of the soils tested. The SWC-HPC may therefore be used only to simulate soil bulk densities and moistui e status at saturation, field capacity and wilting point in the study locations.

  4. Migration characteristics of cobalt-60 through sandy soil in high pH solution

    International Nuclear Information System (INIS)

    Ohnuki, Toshihiko

    1992-01-01

    Migration characteristics of 60 Co through sandy soil in high pH solution has been investigated by both column and batch techniques. The association of 60 Co with the sandy soil and its components were studied by sequential extraction techniques. The concentration profile of 60 Co in the sandy soil column was composed of two exponential curves showing that 60 Co would consist of immobile and mobile fractions. The immobile 60 Co was retained by the sandy soil and was distributed near the top. Though the mobile 60 Co was little sorbed by soil and migrated through the soil column, maximum concentration of 60 Co in the effluents decreased slightly with increasing path length of the soil column. The sequential extraction of 60 Co from the sandy soil and from its components showed that 60 Co was sorbed by both manganese oxide and clay minerals. And manganese oxide is one of the responsible soil components for the observed decrease in the maximum concentration of 60 Co in the effluents. Although the content of manganese oxide in the sandy soil was 0.13%, manganese oxide is the important component to prevent from the migration of 60 Co in the high pH solution. (author)

  5. [Periodic characteristics of soil CO2 flux in mangrove wetland of Quanzhou Bay, China].

    Science.gov (United States)

    Wang, Zong-Lin; Wu, Yan-You; Xing, De-Ke; Liu, Rong-Cheng; Zhou Gui-Yao; Zhao, Kuan

    2014-09-01

    Mangrove wetland ecosystem in Quanzhou Bay in Fujian Province is newly restored with a regular semidiurnal tide. Soil CO2 concentration in the mangrove soil was determined by Li-840 portable gas analyzer, and periodic characteristics of soil CO2 emission was investigated. The soil CO2 flux in the wetland soil was relatively small because the mangrove was young. The change trends of soil CO2 concentration and flux with time were consistent in Kandelia obovate and Aegiceras corniculatum communities in the intertidal periods. The CO2 concentration and flux in the wetland soil were 557.08-2211.50 μmol · mol(-1) and -0.21-0.40 μmol · m(-2) · s(-1), respectively. The average CO2 flux in the wetland soil was 0.26 μmol · mol(-1) · s(-1) in the intertidal of morning and evening tides (early intertidal) and -0.01 μmol · m(-2) · s(-1) in the intertidal of evening and morning tides (late intertidal), respectively. At the same time after the tide, the concentration and flux of CO2 in the mangrove soil in early intertidal was higher than that in late intertidal. In early intertidal, the relationship between the flux and instantaneous concentration of CO2 in the wetland soil was expressed as a bell-shaped curve, and CO2 flux increased first and then decreased with the increasing CO2 concentration, which was in conformity with Gaussian distribution.

  6. A Spreadsheet for Estimating Soil Water Characteristic Curves (SWCC)

    Science.gov (United States)

    2017-05-01

    SWCCs. The spreadsheet presented herein utilizes different methods that use basic soil properties, such as grain size distribution and Atterberg...model. The spreadsheet calculates the SWCCs using seven different methods for comparison. It also compares four closed form models, Gardner (1958...installed instrumentation To perform a transient seepage analysis using modeling programs like SEEP/W (Geo-Slope 2012), it is required to provide the

  7. Compaction and consolidation characteristics of lateritic soil of a ...

    African Journals Online (AJOL)

    Compaction tests indicate maximum dry densities of 2.05Mgm-3, 1.78Mgm-3, and 1.69Mgm-3 at optimum moisture contents of 14.3%, 20.7% and 19.6% for soil samples obtained from BH1, BH2 and BH3 respectively. Compression indices (Cc) obtained from oedometer tests are 0.04816, 0.03820 and 0.04318 while the ...

  8. Physical Characteristics of Some Soils from the Middle East

    Science.gov (United States)

    1993-05-01

    containing sponge spicules indicates a localized sedimentary source for the grains, most likely of a marine origin. Some of the rock fragments show...micritic to silty micritic), < 1 % sedimentary rock fragment (fossiliferous chert/ sponge spicules ), 3% metamorphic rock fragments (metaquartzite, epidote...Ostrich involved building a minefield in soils comparable to those that occur in the Middle East: a site at the Marine Corps Air Ground Combat Center

  9. [Microbial eco-characterization and its restoration in copper reclaimed wasteland in red soil area of China. II. Effects on soil microbial characteristics and community structure].

    Science.gov (United States)

    Long, Jian; Huang, Changyong; Teng, Ying; Yao, Huaiying

    2004-02-01

    Soil microbial features in Lipu copper mining and non-mine soil were studied comparatively. The results indicated that mine soil possessed obviously different microbial features such as lower microbial biomass carbon and soil basal respiration strength, Cmic/Corg decreasing, and higher microbial ecophysiological parameters qCO2, indicating that heavy metal had a depressive impact on soil microbial eco-characteristics. Biolog data showed that mine soil microbial community structure was changed obviously, the speed and quantity of carbon consuming were increased significantly, and the kinds of carbon sources which soil microorganism used were changed, led to consume much more energies for maintaining the normal needs of its life. But the utilization efficiency was lower compared with the control. All the results showed that soil microbial eco-characteristics could be used as a sensitive, effective and liable index of mine soil environment qualities.

  10. [Characteristics of soil water movement using stable isotopes in red soil hilly region of northwest Hunan].

    Science.gov (United States)

    Tian, Ri-Chang; Chen, Hong-Song; Song, Xian-Fang; Wang, Ke-Lin; Yang, Qing-Qing; Meng, Wei

    2009-09-15

    Stable isotope techniques provide a new approach to study soil water movement. The process of water movement in soils under two kinds of plant types (oil tea and corn) were studied based on the observed values of hydrogen and oxygen isotopes of precipitation and soil water at different depths in red-soil sloping land. The results showed that stable isotopes of precipitation in this area had obvious seasonal effect and rainfall effect. The stable isotopes at 0-50 cm depth in oil tea forestland and at 0-40 cm depth in corn cropland increased with the increase in depth, respectively, but they had the opposite tendency after rainfall in arid time. The stable isotopes decreased with the increase in depth below 50 cm depth in oil tea forestland and below 40 cm depth in corn cropland where evaporation influence was weak. The infiltrate rate of soil in oil tea land was affected by precipitation obviously, and it was about 50-100 mm/d after 2-3 days in heavy rain, slowed sharply later, and soil water at 50 cm depth often became a barrier layer. The permeability of soil in corn land was poor and the infiltration rate was lower. The change of stable isotopes in soil water in red soil hilly region was mainly affected by the mixing water which was formed by the antecedent precipitation, and evaporation effect took the second place. The evaporation intensity in oil tea land was lower than that in corn land, but the evaporation depth was higher.

  11. Soil Physical Characteristics and Biological Indicators of Soil Quality Under Different Biodegradable Mulches

    Science.gov (United States)

    Schaeffer, S. M.; Flury, M.; Sintim, H.; Bandopadhyay, S.; Ghimire, S.; Bary, A.; DeBruyn, J.

    2015-12-01

    Application of conventional polyethylene (PE) mulch in crop production offers benefits of increased water use efficiency, weed control, management of certain plant diseases, and maintenance of a micro-climate conducive for plant growth. These factors improve crop yield and quality, but PE must be retrieved and safely disposed of after usage. Substituting PE with biodegradable plastic mulches (BDM) would alleviate disposal needs, and is potentially a more sustainable practice. However, knowledge of potential impacts of BDMs on agricultural soil ecosystems is needed to evaluate sustainability. We (a) monitored soil moisture and temperature dynamics, and (b) assessed soil quality upon usage of different mulches, with pie pumpkin (Cucurbita pepo) as the test crop. Experimental field trials are ongoing at two sites, one at Northwestern Washington Research and Extension Center, Mount Vernon, WA, and the other at East Tennessee Research and Education Center, Knoxville, TN. The treatments constitute four different commercial BDM products, one experimental BDM; no mulch and PE served as the controls. Soil quality parameters being examined include: organic matter content, aggregate stability, water infiltration rate, CO2 flux, pH, and extracellular enzyme activity. In addition, lysimeters were installed to examine the soil water and heat flow dynamics. We present baseline and the first field season results from this study. Mulch cover appeared to moderate soil temperatures, but biodegradable mulches also appeared to lose water more quickly than PE. All mulch types, with the exception of cellulose, reduced the diurnal fluctuations in soil temperature at 10cm depth from 1 to 4ºC. However, volumetric water content ranged from 0.10 to 0.22 m3 m-3 under the five biodegradable mulches compared to 0.22 to 0.28 m3 m-3 under conventional PE. Results from the study will be useful for management practices by providing knowledge on how different mulches impact soil physical and

  12. Analysis on Soil Seed Bank Diversity Characteristics and Its Relation with Soil Physical and Chemical Properties after Substrate Addition.

    Science.gov (United States)

    He, Mengxuan; Lv, Lingyue; Li, Hongyuan; Meng, Weiqing; Zhao, Na

    2016-01-01

    Considered as an essential measure in the application of soil seed bank (SSB) projects, the mixing of substrate and surface soil can effectively improve soil condition. This research is aimed at exploring the diversity characteristics of SSBs and the relationships between SSBs and soil properties. Canonical correspondence analysis (CCA) was adopted to describe the ordination of SSBs on soil properties' gradients; multiple linear regressions were adopted to analyze the relationship between average growth height and soil properties, density and soil properties. Experimental groups of mixed substrate (the mixture of organic and inorganic substrates) had high diversity indexes, especially the Shannon-Wiener Index compared with those of single substrate. Meanwhile, a higher number of species and increased density were also noted in those of mixed substrate. The best test group, No.16, had the highest diversity indexes with a Shannon-Wiener of 1.898, Simpson of 0.633 and Pielou of 0.717, and also showed the highest density of 14000 germinants /m2 and 21 species. In addition, an improvement of the soil's chemical and physical properties was noted when the substrates were mixed. The mixed substrate of turfy soil and perlite could effectively enhance the soil moisture content, whilst a mixed substrate of rice husk carbon and vermiculite could improve the content of available potassium (AK) and phosphorus (AP) and strengthen soil fertility. The germinated plants also reflected obvious regularities of ordination on soil factor gradients. Three distinct cluster groups were presented, of which the first cluster was distributed in an area with a relatively higher content of AK and AP; the second cluster was distributed at places with relatively higher soil moisture content; and the third cluster of plants didn't show any obvious relationship with soil physical and chemical properties. Through CCA analysis, AK and AP were considered the most important soil factors to influence

  13. Analysis on Soil Seed Bank Diversity Characteristics and Its Relation with Soil Physical and Chemical Properties after Substrate Addition.

    Directory of Open Access Journals (Sweden)

    Mengxuan He

    Full Text Available Considered as an essential measure in the application of soil seed bank (SSB projects, the mixing of substrate and surface soil can effectively improve soil condition. This research is aimed at exploring the diversity characteristics of SSBs and the relationships between SSBs and soil properties.Canonical correspondence analysis (CCA was adopted to describe the ordination of SSBs on soil properties' gradients; multiple linear regressions were adopted to analyze the relationship between average growth height and soil properties, density and soil properties.Experimental groups of mixed substrate (the mixture of organic and inorganic substrates had high diversity indexes, especially the Shannon-Wiener Index compared with those of single substrate. Meanwhile, a higher number of species and increased density were also noted in those of mixed substrate. The best test group, No.16, had the highest diversity indexes with a Shannon-Wiener of 1.898, Simpson of 0.633 and Pielou of 0.717, and also showed the highest density of 14000 germinants /m2 and 21 species. In addition, an improvement of the soil's chemical and physical properties was noted when the substrates were mixed. The mixed substrate of turfy soil and perlite could effectively enhance the soil moisture content, whilst a mixed substrate of rice husk carbon and vermiculite could improve the content of available potassium (AK and phosphorus (AP and strengthen soil fertility. The germinated plants also reflected obvious regularities of ordination on soil factor gradients. Three distinct cluster groups were presented, of which the first cluster was distributed in an area with a relatively higher content of AK and AP; the second cluster was distributed at places with relatively higher soil moisture content; and the third cluster of plants didn't show any obvious relationship with soil physical and chemical properties. Through CCA analysis, AK and AP were considered the most important soil factors to

  14. Dynamics and characteristics of soil temperature and moisture of active layer in central Tibetan Plateau

    Science.gov (United States)

    Zhao, L.; Hu, G.; Wu, X.; Tian, L.

    2017-12-01

    Research on the hydrothermal properties of active layer during the thawing and freezing processes was considered as a key question to revealing the heat and moisture exchanges between permafrost and atmosphere. The characteristics of freezing and thawing processes at Tanggula (TGL) site in permafrost regions on the Tibetan Plateau, the results revealed that the depth of daily soil temperature transmission was about 40 cm shallower during thawing period than that during the freezing period. Soil warming process at the depth above 140 cm was slower than the cooling process, whereas they were close below 140 cm depth. Moreover, the hydro-thermal properties differed significantly among different stages. Precipitation caused an obviously increase in soil moisture at 0-20 cm depth. The vertical distribution of soil moisture could be divided into two main zones: less than 12% in the freeze state and greater than 12% in the thaw state. In addition, coupling of moisture and heat during the freezing and thawing processes also showed that soil temperature decreased faster than soil moisture during the freezing process. At the freezing stage, soil moisture exhibited an exponential relationship with the absolute soil temperature. Energy consumed for water-ice conversion during the freezing process was 149.83 MJ/m2 and 141.22 MJ/m2 in 2011 and 2012, respectively, which was estimated by the soil moisture variation.

  15. Soils of Sub-Antarctic tundras: diversity and basic chemical characteristics

    Science.gov (United States)

    Abakumov, Evgeny; Vlasov, Dmitry; Mukhametova, Nadezhda

    2014-05-01

    Antarctic peninsula is known as specific part of Antarctica, which is characterizes by humid and relatively warm climate of so-called sub Antarctic (maritime) zone. Annual precipitation and long above zero period provides the possibility of sustainable tundra's ecosystem formation. Therefore, the soil diversity of these tundra landscapes is maximal in the whole Antarctic. Moreover, the thickness of parent material debris's is also highest and achieves a 1 or 2 meters as highest. The presence of higher vascular plants Deshampsia antarctica which is considered as one of the main edificators provides the development of humus accumulation in upper solum. Penguins activity provides an intensive soil fertilization and development of plant communities with increased density. All these factors leads to formation of specific and quite diverse soil cover in sub Antarctic tundra's. These ecosystems are presented by following permafrost affected soils: Leptosols, Lithoosols, Crysols, Gleysols, Peats and Ornhitosols. Also the post Ornhitosols are widely spreaded in subantarcic ecosystems, they forms on the penguin rockeries during the plant succession development, leaching of nutrients and organic matter mineralization. "Amphibious" soils are specific for seasonal lakes, which evaporates in the end if Australian summer. These soils have specific features of bio sediments and soils as well. Soil chemical characteristic as well as organic matter features discussed in comparison with Antacrtic continental soil in presentation.

  16. Physical, chemical and mineralogical characteristics of some selected gardud soils of kordofan region

    International Nuclear Information System (INIS)

    Elgubshawi, Abdelmoneim Ahmed Ismail

    1995-05-01

    Recently much of the attention is given to gardud soil as the main alternative for the depleted marginal sandy soils. A lack of exact knowledge regarding these soils are evident. For studying gardud soil four sites were chosen according to the annual rainfall. Two pits were excavated in each site to represent the concaved and convexed locations plus composite samples to cover the area between two pits. Morphological, physical, chemical and mineralogical investigations were made. The results showed that the gardud soils were relatively differed within and between sites due to the climate and the topography. The dominant clay minerals are kaolinite, montmorillonite and illte. The chemical and physical characteristics were poor. Some of the restrictions limiting the use of these soils such as erosion, hardness, fertility, stoniness, drought and acidity. According to the American system of soil classification, the soils studied were given the following classification: (1) Bardab soil: (A) Kanhablic rhodustalf-fine clay, kaolinite, isohyperthermic (concaved). (B) Kandic paleustalf-very fine clay, kaolinite, isohyperthermic (convexed). (2) Sodari: (A) Typic comborthid-coarse loamy, mixed hyperthermic (concave). (B) Typic comborthid-coarse loamy, mixed hyperthermic (convexed). (3) Nihud (Rahad Elsilk): (A) Rhodic paleustalf-fine loamy, kaolinite isohyperthermic (concaved). (B) Aridic paleustalf-fine loamy kaolinite isohyperthermic (convexed). (4) Umgamalla: (A) Ustic hapustalf-fine loamy kaolinite isohyperthermic (concaved). (B)Ustic hapustalf-fine loamy kaolinite isohyperthermic (convexed). (Author)

  17. A practical approach to obtain the soil freezing characteristic curve and the freezing/melting point of a soil-water system

    NARCIS (Netherlands)

    Aukenthaler, Manuel; Brinkgreve, R.B.J.; Haxaire, A

    2016-01-01

    Knowing that extensive field tests and laboratory tests are time-consuming and expensive, this paper describes a practical approach to obtain crucial properties of frozen soil such as the soil freezing characteristic curve (SFCC), the freezing/melting point of a soil-water system and its hydraulic

  18. Analysis of the influence of granular fractions on geotechnical characteristics for soils with similar behavior

    Directory of Open Access Journals (Sweden)

    Cornelia-Florentina DOBRESCU

    2014-07-01

    Full Text Available The paper presents a series of experimental tests related to the influence of granular fractions on geotechnical characteristics, using different methods of investigation and assessment. The soil samples selected for the study were collected from two different areas in Romania (Tulcea and Calafat, where similar soil categories were intercepted from the point of view of properties and behavior. Based on laboratory tests, the analysis consisted in establishing the predominant lithological types, the results being processed in order to reveal the variation of specific properties. The research has allowed conducting comparative and correlative analyses, based on the characteristics of soil types (silty and sandy loess, which led to outlined similarities of studied collapsible soils.

  19. Spectral reflectance characteristics of soils in northeastern Brazil as influenced by salinity levels.

    Science.gov (United States)

    Pessoa, Luiz Guilherme Medeiros; Freire, Maria Betânia Galvão Dos Santos; Wilcox, Bradford Paul; Green, Colleen Heather Machado; De Araújo, Rômulo José Tolêdo; De Araújo Filho, José Coelho

    2016-11-01

    In northeastern Brazil, large swaths of once-productive soils have been severely degraded by soil salinization, but the true extent of the damage has not been assessed. Emerging remote sensing technology based on hyperspectral analysis offers one possibility for large-scale assessment, but it has been unclear to what extent the spectral properties of soils are related to salinity characteristics. The purpose of this study was to characterize the spectral properties of degraded (saline) and non-degraded agricultural soils in northeastern Brazil and determine the extent to which these properties correspond to soil salinity. We took soil samples from 78 locations within a 45,000-km 2 site in Pernambuco State. We used cluster analysis to group the soil samples on the basis of similarities in salinity and sodicity levels, and then obtained spectral data for each group. The physical properties analysis indicated a predominance of the coarse sand fraction in almost all the soil groups, and total porosity was similar for all the groups. The chemical analysis revealed different levels of degradation among the groups, ranging from non-degraded to strongly degraded conditions, as defined by the degree of salinity and sodicity. The soil properties showing the highest correlation with spectral reflectance were the exchangeable sodium percentage followed by fine sand. Differences in the reflectance curves for the various soil groups were relatively small and were not significant. These results suggest that, where soil crusts are not present, significant challenges remain for using hyperspectral remote sensing to assess soil salinity in northeastern Brazil.

  20. Undesirable Effects of Media on Children: Why Limitation is Necessary?

    Science.gov (United States)

    Karaagac, Aysu Turkmen

    2015-06-01

    Pervasive media environment is a social problem shared by most of the countries around the world. Several studies have been performed to highlight the undesired effects of media on children. Some of these studies have focused on the time spent by children watching television, playing with computers or using mobile media devices while some others have tried to explain the associations between the obesity, postural abnormalities or psychological problems of children, and their media use. This article discusses the recent approaches to curb influence of media on children, and the importance of family media literacy education programs with particular relevance to developing countries.

  1. Predicting Soil-Water Characteristics from Volumetric Contents of Pore-Size Analogue Particle Fractions

    DEFF Research Database (Denmark)

    Naveed, Muhammad; Møldrup, Per; Tuller, Markus

    *-model) for the SWC, derived from readily available soil properties such as texture and bulk density. A total of 46 soils from different horizons at 15 locations across Denmark were used for models evaluation. The Xw-model predicts the volumetric water content as a function of volumetric fines content (organic matter......Modelling water distribution and flow in partially saturated soils requires knowledge of the soil-water characteristic (SWC). However, measurement of the SWC is challenging and time-consuming, and in some cases not feasible. This study introduces two predictive models (Xw-model and Xw...... (organic matter, clay, silt, fine and coarse sand), variably included in the model depending on the pF value. The volumetric content of a particular soil particle size fraction was included in the model if it was assumed to contribute to the pore size fraction still occupied with water at the given p...

  2. Relating Bioavailability Parameters to the Sorbent Characteristics of PAH Polluted Soils

    DEFF Research Database (Denmark)

    Bartolome, N.; Hilber, I.; Schulin, R.

    2015-01-01

    Regulation of Hydrophobic Organic Contaminants (HOC) such as polycyclic aromatic hydrocarbons (PAHs) in soil is still based on total concentrations. However, many studies have demonstrated that not all of a pollutant’s content in soil is equally available to organisms (Reichenberg & Mayer 2006...... to several sorbent characteristics including organic and black carbon content. The results will provide a better understanding of bioavailability of PAHs in soils. Moreover, the outcomes will be discussed regarding to the potential application of chemical proxies in soil pollution risk assessment......). Over the last decade, intensive effort has been made to incorporate bioavailability into risk assessment (Cachada et al. 2014). Here, we compare total concentrations of PAH with two bioavailability parameters in 30 different soil samples from the archive of the standardized National and Zurich Cantonal...

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

    Directory of Open Access Journals (Sweden)

    abolfazl azadi

    2017-01-01

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

  4. Reuse of Ablution Water to Improve Peat Soil Characteristics for Ornamental Landscape Plants Cultivation

    Directory of Open Access Journals (Sweden)

    Radin Mohamed Radin Maya Saphira

    2017-01-01

    Full Text Available The present study aimed to reuse of ablution water for washing peat soil in order to reduce the concentrations of heavy metals in these soils which might effect negatively on the plant growth. The washing process design was similar to horizontal subsurface flow constructed wetlands (HSSFCW consist of layers of peat and sand soil and surrounded by gravel on both sides. Strelitzia sp. was used to detect the presence negative effect of the washing process on the morphological characteristics of the plants. The physical and chemical characteristics of ablution water was examined before and after the washing process by using Inductively Couple Plasma- Mass Spectrometer (ICP-MS Atomic Absorption Spectrometer (AAS. The characteristics of peat soil before and after the washing process were examined by using X-Ray Fluorescence (XRF. The results revealed that the percentage of FeO3in peat soil reduced from 45.80 to 1.01%. The percentage of SiO2 in sand soil dropped from 87.7 to 67.10%. Parameters of ablution water resulted from the washing process which including Biological Oxygen Demand (BOD5 and heavy metals have increased but still within the standard limits for the disposal of ablution water into the environment. No atrophy was observed in Strelitzia sp. leaves, indicating the ability of plant to grow normally. It can be concluded that the utilization of ablution water in the washing of peat soil has improve the characteristics of the soil without effect on their organic constitutes.

  5. Characteristics of Major Lowland Rice-growing Soils in the Guinea ...

    African Journals Online (AJOL)

    Characteristics of Major Lowland Rice-growing Soils in the Guinea Savanna Voltaian Basin of Ghana. ... Les propriétés physiques du sol étaient utilisées comme les paramètres principaux et l'estimation adaptée du Sys et al. ... Soil physical properties were used as the main parameters and ratings adapted from Sys et al.

  6. Challenges of conservation agriculture practices on silty soils. Effects on soil pore and gas transport characteristics in North-eastern Italy

    DEFF Research Database (Denmark)

    Piccoli, Ilaria; Schjønning, Per; Lamandé, Mathieu

    2017-01-01

    characteristics. The poor structural stability of Veneto soils, particularly the poor soil organic carbon content, could prevent the exploitation of CA practices firstly on soil structure and in turn on gas exchanges. For these reasons further studies elucidating the mechanisms improving soil structural......Soil air exchange is one of the most important soil functions that directly impacts on crop productivity and environment. Generally, conservation agriculture (CA) practices are expected to provide improved soil aeration but contrasting texture-related effects were found in the literature. The aim...... of this study was to evaluate the effect of CA practices on gas transport characteristics in the silty soils of the Veneto Region (North-Eastern Italy). In 2010, a field experiment comparing CA practices (no-tillage, cover crop and residues retention) to conventional intensive tillage (IT) system...

  7. Characteristics and distribution of soil piping erosion in loess-derived soils of Belgium

    International Nuclear Information System (INIS)

    Verachtert, E.; Van Den Eeckhaut, M.; Poesen, J.; Deckers, J.

    2009-01-01

    Subsurface erosion (piping, tunnel erosion) in non-karstic landscapes has been considered of little importance compared to sheet and gully erosion for a long time. Although the basic factors responsible for piping in certain environments are well understood, there is still uncertainty about the topographic and soil properties inducing subsurface pipe development in loess-derived soils under temperate climate. Therefore, this research aims at understanding the factors controlling the occurrence of piping erosion in the loess-derived soils of the Flemish Ardennes (Belgium). Analysis of ortho photos as well as field surveys were conducted to detect the sites with piping in the study area. Enquiries among farmers and technical services were carried out. In total, 114 sites (parcels) with 301 collapsed soil pipes were found in a 170 kM 2 study area. For each site with piping, data was collected on possible controlling factors: topographic parameters, land use, lithology and soil type. Land use plays an important role as 94% of the sites with piping are found under pasture. (Author) 15 refs.

  8. Characteristics and distribution of soil piping erosion in loess-derived soils of Belgium

    Energy Technology Data Exchange (ETDEWEB)

    Verachtert, E.; Van Den Eeckhaut, M.; Poesen, J.; Deckers, J.

    2009-07-01

    Subsurface erosion (piping, tunnel erosion) in non-karstic landscapes has been considered of little importance compared to sheet and gully erosion for a long time. Although the basic factors responsible for piping in certain environments are well understood, there is still uncertainty about the topographic and soil properties inducing subsurface pipe development in loess-derived soils under temperate climate. Therefore, this research aims at understanding the factors controlling the occurrence of piping erosion in the loess-derived soils of the Flemish Ardennes (Belgium). Analysis of ortho photos as well as field surveys were conducted to detect the sites with piping in the study area. Enquiries among farmers and technical services were carried out. In total, 114 sites (parcels) with 301 collapsed soil pipes were found in a 170 kM{sup 2} study area. For each site with piping, data was collected on possible controlling factors: topographic parameters, land use, lithology and soil type. Land use plays an important role as 94% of the sites with piping are found under pasture. (Author) 15 refs.

  9. [Variation characteristics of soil carbon sequestration under long-term different fertilization in red paddy soil].

    Science.gov (United States)

    Huang, Jing; Zhang, Yang-zhu; Gao, Ju-sheng; Zhang, Wen-ju; Liu, Shu-jun

    2015-11-01

    The objective of this study was to clarify the changes of soil organic carbon (SOC) content, the saturation capacity of soil carbon sequestration and its cooperation with carbon input (crop source and organic fertilizer source carbon) under long-term (1982-2012) different fertilization in red paddy soil. The results showed that fertilization could increase SOC content. The SOC content of all the fertilization treatments demonstrated a trend of stabilization after applying fertilizer for 30 years. The SOC content in the treatments applying organic manure with mineral fertilizers was between 21.02 and 21.24 g · kg(-1), and the increase rate ranged from 0.41 to 0.59 g · kg(-1) · a(-1). The SOC content in the treatments applying mineral fertilizers only was 15.48 g · kg(-1). The average soil carbon sequestration in the treatments that applied organic manure with mineral fertilizers ranged from 43.61 to 48.43 t C · hm(-2), and the average SOC storage over the years in these treatments was significantly greater than those applying mineral fertilizers only. There was an exponentially positive correlation between C sequestration efficiency and annual average organic C input. It must input exogenous organic carbon at least at 0. 12 t C · hm(-2) · a(-1) to maintain the balance of soil organic carbon under the experimental conditions.

  10. Characteristics of Soil Humic Substances as Determined by Conventional and Synchrotron Fourier Transform Infrared Spectroscopy

    Science.gov (United States)

    Wang, S.; Song, X. Y.; Wang, N.; Li, C. X.; Wang, W.; Zhang, J. J.

    2014-11-01

    Humic substances (HS) play an important role in soil fertility and carbon sequestration in soil. The structural characteristics of soil HS, extracted from two natural soils and a laboratory-incubated soil, were investigated by conventional beamline-based Fourier transform infrared radiation (CB-FTIR), a common FTIR technique based on a conventional thermal source, and synchrotron radiation-based (SR-FTIR) spectroscopy. The relative area of absorbance peaks that appeared at 2930, 2860, 1711, and 1635 cm-1 were calculated to make a comparison of the absorbance intensities. The absorption of aromatic functional groups of HS was stronger in SR-FTIR spectroscopy than in CB-FTIR spectroscopy. Compared with humic acid extracted with a 0.1 mol/l Na4P2O7 solution, the level of aliphaticity in humic acid extracted with a 0.1 mol/l NaOH solution was higher. The aliphaticity of humin associated with clay (HMc) was higher than that of humin associated with iron (HMi). These results suggest that SR-FTIR spectroscopy is a useful and nondestructive technique to study the structural characteristics of soil humic substances. Sequential extraction of soil humic substances with NaOH and Na4P2O7 solutions may be helpful in providing additional information in cases where differences in the material obtained from different extraction solutions occur. The aliphaticity and complexity of HMc were higher than those of HMi.

  11. Undesirable substances in vegetable oils: anything to declare?

    Directory of Open Access Journals (Sweden)

    Lacoste Florence

    2014-01-01

    Full Text Available The presence of undesirable compounds in vegetable and animal oils and fats may have many different origins. Although the potential toxicity of most of these undesirable compounds is real, poisoning risks are rather limited due to the efficient elimination during oil-refining steps, careful conditioning, choice of efficient packaging and industrial quality control management. However the research of contaminants is part of multiple controls conducted by fat and oil industry to verify the conformity of products placed on the market in relation to regulations such as the European commission regulation EC No. 1881/2006 setting maximum levels for some contaminants in food as lead, some mycotoxins, dioxins, polychlorobiphenyls, benzo[a]pyrene. In the absence of regulation, the detection of contaminants must be addressed in partnership with authorities according to the toxicity of molecules. The controls are not confined to environmental contaminants. They also include compounds that can be formed during the production process of vegetable oils such as esters of 3-monochloropropanediol. This article focuses more particularly on heavy metals, polycyclic aromatic hydrocarbons, mineral oils, phthalates and 3-MCPD or glycidyl esters. Aspects such as methods for analysis, limits fixed by EC regulation and occurrence in vegetable oils are discussed.

  12. Effects of Biochar on Adsorption Characteristics of Water-soluble Fluorine in Tea Garden Soil

    Directory of Open Access Journals (Sweden)

    SUN Yong-hong

    2017-06-01

    Full Text Available The adsorption characteristics of water-soluble fluoride with application of biochar in tea garden soil was studied by indoor culture test. The results showed that the adsorption quantity and adsorption rate of water-soluble fluorine decreased gradually with the increase of biochar amounts in tea garden soil. The isothermal adsorption of Langmuir equation, Freundlich equation and Temkin equation could be better used to describe the adsorption law of water-soluble fluorine, and the Freundlich equation had the best fitting curve. With the increase of biochar content of soil, the net amount of fluoride adsorption reduced gradually. The adsorption kinetics of fluoride in soil was characterized by fast adsorption and slow reaction stages. The equilibrium time was less than 120 min for the rapid increase of adsorption, 0.25% and 0.50% biomass carbon content treatments of the soil reached to equilibrium after 1 440 min. The results of theoretic calculation were in good agreement with experimental adsorption quantity by dual constant equation, Elovich equation and first order kinetics equation, which could accurately describe the adsorption process of water-soluble fluorine in soil with biochar. The increase of soil pH with the addition of biochar was closely related to the decrease of maximum adsorption quantity, adsorption intensity and net adsorption quantity of water-soluble fluorine in tea garden soil.

  13. GEOTECHNICAL CHARACTERISTICS OF LATERITIC SOIL STABILIZED WITH SAWDUST ASH-LIME MIXTURES

    Directory of Open Access Journals (Sweden)

    Emeka Segun Nnochiri

    2017-04-01

    Full Text Available This study assesses the geotechnical characteristics of lateritic soil and sawdust ash lime (SDAL mixtures. Preliminary tests were carried out on the natural soil sample for identification and classification purposes. The sawdust was mixed with lime for stabilization in the ratio 2:1. This mixture was thereafter added to the lateritic soil in varying proportions of 2, 4, 6, 8 and 10% by weight of soil. Addition of SDAL increased values of Optimum Moisture Content (OMC from 17.0% at 0% SDAL to 26.5% at 10% SDAL by weight of soil, also, values of Maximum Dry Density (MDD decreased from 2040 kg/m3 at 0% SDAL to 1415 kg/m3 at 10% SDAL. Values of Unconfined Compressive Strength (UCS increased from 38.58 kN/m2 at 0% SDAL to highest value of 129.63 kN/m2 at 6% SDAL. The values of liquid limits and plasticity index of the soil were effectively reduced with the addition of the SDAL, from 54.0% at 0% SDAL to 49.0% at 10% SDAL and from 13.7% at 0% SDAL to 12.5% at 10% SDAL respectively. It was therefore concluded that the sawdust ash lime (SDAL mixture can serve as a cheap soil stabilizing agent for poor lateritic soil.

  14. Effect of soil properties on Hydraulic characteristics under subsurface drip irrigation

    Science.gov (United States)

    Fan, Wangtao; Li, Gang

    2018-02-01

    Subsurface drip irrigation (SDI) is a technique that has a high potential in application because of its high efficiency in water-saving. The hydraulic characteristics of SDI sub-unit pipe network can be affected by soil physical properties as the emitters are buried in soils. The related research, however, is not fully explored. The laboratory tests were carried out in the present study to determine the effects of hydraulic factors including operating pressure, initial soil water content, and bulk density on flow rate and its sensitivity to each hydraulic factor for two types of SDI emitters (PLASSIM emitter and Heping emitter). For this purpose, three soils with contrasting textures (i.e., light sand, silt loam, and light clay) were repacked with two soil bulk density (1.25 and1.40 g cm-3) with two initial soil water content (12% and 18%) in plexiglass columns with 40 cm in diameter and 40 cm in height. Drip emitters were buried at depth of 20 cm to measure the flow rates under seven operating pressures (60, 100, 150, 200, 250, 300, and 370 kPa). We found that the operating pressure was the dominating factor of flow rate of the SDI emitter, and flow rate increased with the increase of operating pressure. The initial soil water content and bulk density also affected the flow rate, and their effects were the most notable in the light sand soil. The sensitivity of flow rate to each hydraulic factor was dependent on soil texture, and followed a descending order of light sand>silt loam>light clay for both types of emitters. Further, the sensitivity of flow rate to each hydraulic factor decreased with the increase of operating pressure, initial soil water content, and bulk density. This study may be used to guide the soil specific-design of SDI emitters for optimal water use and management.

  15. Characteristics of current roadside pollution of soils in Upper Silesia

    Science.gov (United States)

    Wawer, M.; Szuszkiewicz, M.; Magiera, T.

    2012-04-01

    The aim of the study was qualitative recognition of contemporary roadside pollutants deposited on topsoils in areas located in close vicinity to roads with high traffic volume (main roads, ring roads). So far, the determination of pollutant content in soil samples has shown only the amount of pollutants deposited on soils over long time period, without the possibility to assess the quality changes in type of deposition and to determine the present structure of roadside pollution. Moreover, in many cases, it is difficult to distinguish roadside pollution from other industrial sources. In order to avoid this issue and recognize currently emergent threats of road traffic origin, three monitoring plots filled with quartz sand had been installed in Zabrze, Gliwice and Opole (Poland) close to arteries with high traffic volume. For installation of monitoring plots 7 cm of topsoil had been removed and replaced by boxes filled with clean quartz sand with known chemical composition and neutral magnetic properties (diamagnetic). This sand was treated as neutral matrix for the accumulation of traffic pollution. Results of chemical analyses of heavy metal contents and magnetic susceptibility measurements of removed topsoils have shown that the highest content of Fe, Mn, Zn, Pb, Cu, Cr and Ni were observed in Zabrze. Amount of Zn and Pb exceeded threshold values. Magnetic susceptibility values were also the highest in Zabrze. In all investigated areas magnetic susceptibility values and heavy metal contents decreased with the distance from the road. Measurements of sand from monitoring plots which were executed after 3, 6 and 12 months of exposure have shown that values of magnetic susceptibility have increased during these time periods. It is visible especially in surface layer of sand. Initially magnetic susceptibility value of quartz sand which was used as matrix after first year of exposure increased from 0,25 - 10-8 m3kg-1 to 300 in Zabrze, 50 in Gliwice and 30- 10-8 m3kg-1

  16. Relations of microbiome characteristics to edaphic properties of tropical soils from Trinidad

    Directory of Open Access Journals (Sweden)

    Vidya eDe Gannes

    2015-09-01

    Full Text Available Understanding how community structure of Bacteria, Archaea and Fungi varies as a function of edaphic characteristics is key to elucidating associations between soil ecosystem function and the microbiome that sustains it. In this study, non-managed tropical soils were examined that represented a range of edaphic characteristics, and a comprehensive soil microbiome analysis was done by Illumina sequencing of amplicon libraries that targeted Bacteria (universal prokaryotic 16S rRNA gene primers, Archaea (primers selective for archaeal 16S rRNA genes or Fungi (internal transcribed spacer region. Microbiome diversity decreased in the order: Bacteria > Archaea > Fungi. Bacterial community composition had a strong relationship to edaphic factors while that of Archaea and Fungi was comparatively weak. All communities were significantly more similar within soils, than they were between soils (ANOSIM p < 0.001; bacterial communities were 70-80% alike, while communities of Fungi and Archaea had 40-50% similarity. Communities differed in species turnover patterns, such that two soils with relatively similar bacterial communities could not be predicted to be similar in composition of Archaea or Fungi. Bacterial and archaeal diversity had significant (negative correlations to pH, whereas fungal diversity was not correlated to pH. Edaphic characteristics that best explained variation between soils in bacterial community structure were: total carbon, sodium, magnesium and zinc. For fungi, the best variables were: sodium, magnesium, phosphorus, boron and C/N. Archaeal communities had two sets of edaphic factors of equal strength, one contained sulphur, sodium, and ammonium-N and the other was composed of clay, potassium, ammonium-N, and nitrate-N. Collectively, the data indicate that Bacteria, Archaea and Fungi did not closely parallel one another in community structure development, and thus microbiomes in each soil acquired unique identities. This divergence

  17. [Carbon Source Utilization Characteristics of Soil Microbial Community for Apple Orchard with Interplanting Herbage].

    Science.gov (United States)

    Du, Yi-fei; Fang, Kai-kai; Wang, Zhi-kang; Li, Hui-ke; Mao, Peng-juan; Zhang, Xiang-xu; Wang, Jing

    2015-11-01

    As soil fertility in apple orchard with clean tillage is declined continuously, interplanting herbage in orchard, which is a new orchard management model, plays an important role in improving orchard soil conditions. By using biolog micro-plate technique, this paper studied the functional diversity of soil microbial community under four species of management model in apple orchards, including clear tillage model, interplanting white clover model, interplanting small crown flower model and interplanting cocksfoot model, and the carbon source utilization characteristics of microbial community were explored, which could provide a reference for revealing driving mechanism of ecological process of orchard soil. The results showed that the functional diversity of microbial community had a significant difference among different treatments and in the order of white clover > small crown flower > cocksfoot > clear tillage. The correlation analysis showed that the average well color development (AWCD), Shannon index, Richness index and McIntosh index were all highly significantly positively correlated with soil organic carbon, total nitrogen, microbial biomass carbon, and Shannon index was significantly positively correlated with soil pH. The principal component analysis and the fingerprints of the physiological carbon metabolism of the microbial community demonstrated that grass treatments improved carbon source metabolic ability of soil microbial community, and the soil microbes with perennial legumes (White Clover and small crown flower) had a significantly higher utilization rate in carbohydrates (N-Acetyl-D-Glucosamine, D-Mannitol, β-Methyl-D-Glucoside), amino acids (Glycyl-L-Glutamic acid, L-Serine, L-Threonine) and polymers (Tween 40, Glycogen) than the soil microbes with clear tillage. It was considered that different treatments had the unique microbial community structure and peculiar carbon source utilization characteristics.

  18. Ancient coins: cluster analysis applied to find a correlation between corrosion process and burial soil characteristics.

    Science.gov (United States)

    Reale, Rita; Plattner, Susanne H; Guida, Giuseppe; Sammartino, Maria Pia; Visco, Giovanni

    2012-05-02

    Although it is well known that any material degrades faster when exposed to an aggressive environment as well as that "aggressive" cannot be univocally defined as depending also on the chemical-physical characteristics of material, few researches on the identification of the most significant parameters influencing the corrosion of metallic object are available.A series of ancient coins, coming from the archaeological excavation of Palazzo Valentini (Rome) were collected together with soils, both near and far from them, and then analysed using different analytical techniques looking for a correlation between the corrosion products covering the coins and the chemical-physical soil characteristics. The content of soluble salts in the water-bearing stratum and surfacing in the archaeological site, was also measured.The obtained results stress the influence of alkaline soils on formation of patina. Cerussite, probably due to the circulation of water in layers rich in marble and plaster fragments, was the main corrosion product identified by X-ray Diffraction (XRD). Copper, lead and vanadium were found in soil surrounding coins. By measuring conductivity, pH and soluble salts content of the washing solutions from both coins and soils, we could easily separate coins coming from different stratigraphic units of the site.Data were treated by cluster and multivariate analysis, revealing a correlation between part of the coins and the nearby soil samples.

  19. Investigating the soil removal characteristics of flexible tube coring method for lunar exploration

    Science.gov (United States)

    Tang, Junyue; Quan, Qiquan; Jiang, Shengyuan; Liang, Jieneng; Lu, Xiangyong; Yuan, Fengpei

    2018-02-01

    Compared with other technical solutions, sampling the planetary soil and returning it back to Earth may be the most direct method to seek the evidence of extraterrestrial life. To keep sample's stratification for further analyzing, a novel sampling method called flexible tube coring has been adopted for China future lunar explorations. Given the uncertain physical properties of lunar regolith, proper drilling parameters should be adjusted immediately in piercing process. Otherwise, only a small amount of core could be sampled and overload drilling faults could occur correspondingly. Due to the fact that the removed soil is inevitably connected with the cored soil, soil removal characteristics may have a great influence on both drilling loads and coring results. To comprehend the soil removal characteristics, a non-contact measurement was proposed and verified to acquire the coring and removal results accurately. Herein, further more experiments in one homogenous lunar regolith simulant were conducted, revealing that there exists a sudden core failure during the sampling process and the final coring results are determined by the penetration per revolution index. Due to the core failure, both drilling loads and soil's removal states are also affected thereby.

  20. Differentiation characteristics and source analysis of heavy metals in typical brown soil under different vegetation

    Science.gov (United States)

    Dong, Zhicheng; Zhang, Lina; Li, Xueshuang; Lv, Shuangyan; He, Shijie; Liu, Ying; Ma, Xuanxuan

    2017-08-01

    Anomalous enrichment of soil elements (especially heavy metals) has aroused popular attention in China. In order to discuss distribution characteristics and analyze sources of elements in brown soil, field investigation and sample collection were carried out under different vegetation (cherry, apple, bamboos and pine) in Qixia, a typical apple production base in China. Element contents, pH, electrical conductivity (EC) and magnetic susceptibility (MS) were tested. Results showed that element concentrations were about roughly 2.48 times as China’s background values, while significantly lower than the class ii of National soil Environment Quality Standard (Ni excepted). Meanwhile, vertical distribution and accumulation characteristics of elements in typical brown soil were significantly different under different vegetation. In detail, elements (Zn excepted) of Pine soil accumulated in surface, while they (Cd, Arsenic excepted) increased with depth under other vegetation. Moreover, pH and EC changed like elements, while MS was exactly opposite. It was found that those differences above were mainly caused by human activities (such as improper use of fertilizer, pesticide and inadequate use of organic fertilizer, etc.). Additionally, differences in composition and decomposition rate of vegetation litter also resulted in vertical differentiations of soil elements under different vegetation.

  1. Preferential flow characteristics of reclaimed mine soils in a surface coal mine dump.

    Science.gov (United States)

    Gang, Lv; Jun, Li; Yexin, Li; Ting, Wang; Yazhuo, Liu; Xinyang, Fu

    2017-06-01

    There are a large number of macropores/tubular channels of a few centimeters and plant roots in reclaimed dump soils, which are the main reasons for the formation of soil macropores and soil preferential flow. To systematically study the morphological characteristics and variation of soil preferential flow for different reclaimed vegetations in a dump, a dye-staining experiment and physical and chemical analysis were carried out to investigate the formation mechanism and influencing factors of soil preferential flow in the vegetation restoration process. The results indicate that there were differences in the soil water breakthrough curves for different plots. The macropore effluent rate generally increased at first and then tended to stabilize. The soil steady effluent rate decreased with increasing soil depth, which reached the maximum and minimum values at the depths of 0∼5 cm (0.0193∼0.0315 mm s -1 ) and 50∼60 cm (0.0028∼0.0035 mm s -1 ), respectively. Furthermore, the radius of soil macropores under different types of reclaimed vegetation ranged from 0.03 to 4.71 mm, most of which ranged from 0.11 to 2.36 mm. The soil macroporosity of different reclaimed vegetation types ranged from 0.03 to 16.58%, which was significantly greater than 5%. The soil macroporosity determined 65% of the variation in the steady effluent rate and 42% of the variation in the saturated hydraulic conductivity. Furthermore, the dye coverage ratio decreased as the soil layer depth increased in different plots, and there were some differences in each plot. The maximum dye coverage ratio occurred in the 0∼5 cm soil layer, which reached 90.37%. The dye coverage ratio at a depth of 0∼60 cm in six plots followed the order of Robinia pseudoacacia (26.48%) > Ulmus pumila (20.12%) > mixed forest (17.32%) > farmland (15.06%) > shrub (13.97%) > weeds (10.07%). The soil preferential flow mostly occurred in the 0∼40 cm soil depth layer, which occupied more than 93

  2. Study on Dynamic Characteristics of Heavy Machine Tool-Composite Pile Foundation-Soil

    Directory of Open Access Journals (Sweden)

    CAI Li-Gang

    2014-09-01

    Full Text Available Heavy duty computer numerical control machine tools have characteristics of large self-weight, load and. The insufficiency of foundation bearing capacity leads to deformation of lathe bed, which effects machining accuracy. A combined-layer foundation model is created to describe the pile group foundation of multi-soil layer in this paper. Considering piles and soil in pile group as transversely isotropic material, equivalent constitutive relationship of composite foundation is constructed. A mathematical model is established by the introduction of boundary conditions, which is based on heavy duty computer numerical control machine tools-composite pile foundation-soil interaction system. And then, the response of different soil and pile depth is studied by a case. The model improves motion accuracy of machine tools.

  3. [Soil organic pollution characteristics and microbial properties in coal mining areas of Mentougou].

    Science.gov (United States)

    Jia, Jian-Li; Zhang, Yue; Wang, Chen; Li, Dong; Liu, Bo-Wen; Liu, Ying; Zhao, Le; Yang, Si-Qi

    2011-03-01

    Soil micro-ecosystem including organic pollution characteristics, basic physicochemical parameters, and microbial properties was analyzed which contaminated with organic pollutants in coal mining area. Results showed that the organic pollution level in coal mining area soils distributed from 0.4 to 1.5 mg/g dry soil, which was 1. 5-6 times as much as the background sample. Furthermore, the column chromatography and GC-MS analysis revealed that content of lightly components including saturated and aromatic hydrocarbons exceeded 40%, specifically was alkenes (> C15), hydrocarbon derivatives, and a small amount aromatic hydrocarbons. Totally, the components of organic pollutants extracted in soils were similar to which in coal gangue samples, illustrating the source of soil pollution to a certain extent in coal mining areas. The physicochemical factors such as nutrient level and moisture contents were not conducive to the growth and reproduction of microbe except pH level, which might show inhibition to microbial activities. Microbial density of pollutant soils in coal mining areas was totally low, with specific amount 10(4)-10(5) cell/g dry soil and FDA activity 2.0-2.9 mg/(g x min). Generally, the microbial density and activity were decreased as the enhancing pollution level. However, in-depth analysis was needed urgently because of the complex impact of environmental conditions like pH, moisture, and nutrition.

  4. Shrubby Reed-Mustard Habitat: Parent Material, Soil, and Landscape Characteristics

    Science.gov (United States)

    Kelly, L. S.; Boettinger, J. L.

    2012-12-01

    Shrubby reed-mustard (Glaucocarpum suffrutescens, a.k.a. Schoenocrambe suffrutescens, Glaucocarpum suffrutescens, or Hesperidanthus suffrutescens) is an endangered perennial shrub endemic to the southern Uinta Basin in northeast Utah. Only seven populations of shrubby reed-mustard have been identified. The arid area where the plant grows is rich in natural gas and oil deposits, as well as oil shale. Oil wells already dot the landscape, and there is significant concern that further development of these resources will threaten the continued existence of shrubby reed-mustard. Determination of the parent material, soil and landscape characteristics associated with shrubby reed-mustard habitat is imperative to facilitate conservation management. Shrubby reed-mustard grows where little else does and, based on field observations and remotely sensed spectral data, appears to occur in a particular type of strata. Our objective is to identify the physical and chemical characteristics of shrubby reed-mustard's environment. Site characteristics such as parent material and associated vegetation have been identified and documented. Soil properties such as water-soluble and total leachable elements, particle-size distribution, organic carbon, cation exchange capacity, total nitrogen, and available phosphorus and potassium are being determined. During the course of this investigation, soils within four shrubby reed-mustard habitat areas were sampled. Soils from non-shrubby reed-mustard areas adjacent to the four shrubby reed-mustard populations were also sampled. Soil samples were collected from a total of twenty-five shrubby reed-mustard soil pits and twenty-four non-shrubby reed-mustard soil pits. The soil horizons of each pedon were delineated, and samples were collected from each horizon. Field data indicate that shrubby reed-mustard occurs exclusively in shale-derived, shallow soils on bedrock-controlled uplands. Although there is some overlap of plant species on both types

  5. Study of the characteristics of the soil of Chhattisgarh at X-band ...

    Indian Academy of Sciences (India)

    M. Senthilkumar (Newgen Imaging) 1461 1996 Oct 15 13:05:22

    upto a certain transition point and then increase rapidly with moisture content. Keywords. Soil characteristics; complex dielectric constant; Chhattisgarh region; X-band frequency. 1. Introduction. Ground-based studies of the dielectric properties of different earth constituents at microwave frequencies are important as they ...

  6. Long-term impact of Heracleum mantegazzianum invasion on soil chemical and biological characteristics

    Czech Academy of Sciences Publication Activity Database

    Jandová, Kateřina; Klinerová, Tereza; Müllerová, Jana; Pyšek, Petr; Pergl, Jan; Cajthaml, Tomáš; Dostál, Petr

    2014-01-01

    Roč. 68, Jan 2014 (2014), s. 270-278 ISSN 0038-0717 R&D Projects: GA ČR GAP504/10/0132; GA AV ČR IAA600050811 Institutional support: RVO:67985939 ; RVO:61388971 Keywords : invasion * ecosystem modification * soil characteristic Subject RIV: EF - Botanics; EE - Microbiology, Virology (MBU-M) Impact factor: 3.932, year: 2014

  7. Decay characteristics and erosion-related transport of glyphosate in Chinese loess soil under field conditions

    NARCIS (Netherlands)

    Yang, X.; Wang, Fei; Martins Bento, Celia; Meng, L.; Dam, van R.C.J.; Mol, J.G.J.; Liu, Guobin; Ritsema, C.J.; Geissen, V.

    2015-01-01

    The decay characteristics and erosion-related transport of glyphosate and aminomethylphosphonic acid (AMPA) were monitored for 35 d at different slope gradients and rates of application in plots with loess soil on the Loess Plateau, China. The initial glyphosate decayed rapidly (half-life of 3.5 d)

  8. Study of the characteristics of the soil of Chhattisgarh at X-band ...

    Indian Academy of Sciences (India)

    M. Senthilkumar (Newgen Imaging) 1461 1996 Oct 15 13:05:22

    Study of the characteristics of the soil of Chhattisgarh at. X-band frequency. S K SRIVASTAVA and G P MISHRA. Department of Physics, Govt. P. G. College, Ambikapur 497 001, India e-mail: sk−srivastava@yahoo.com. Abstract. The real and imaginary parts (ε1 and ε2) of the complex dielectric constant(ε)of sand, silt and ...

  9. Cosmetics Europe Guidelines on the Management of Undesirable Effects and Reporting of Serious Undesirable Effects from Cosmetics in the European Union

    Directory of Open Access Journals (Sweden)

    Gerald Renner

    2017-01-01

    Full Text Available The European Union (EU Cosmetics Regulation (EC No. 1223/2009 requires companies to collect and assess reports of adverse health effects from the cosmetic products (undesirable effects they market. Furthermore, undesirable effects that are considered as serious need to be reported to the national competent authorities. Cosmetics Europe, representing the European cosmetics industry, has developed these guidelines to promote a consistent practical approach for the management of undesirable effects and the notification of serious undesirable effects. Following these guidelines allows companies concerned to demonstrate due diligence and compliance with the legal requirements.

  10. Physiochemical, site, and bidirectional reflectance factor characteristics of uniformly moist soils. [Brazil, Spain and the United States of America

    Science.gov (United States)

    Stoner, E. R.; Baumgardner, M. F. (Principal Investigator)

    1980-01-01

    The author has identified the following significant results. The bidirectional reflectance factor (0.5 micron to 2.3 micron wavelength interval) and physiochemical properties of over 500 soils from 39 states, Brazil and Spain were measured. Site characteristics of soil temperature regime and moisture zone were used as selection criteria. Parent material and internal drainage were noted for each soil. At least five general types of soil reflectance curves were identified based primarily on the presence or absence of ferric iron absorption bands, organic matter content, and soil drainage characteristics. Reflectance in 10 bands across the spectrum was found to be negatively correlated with the natural log of organic matter content.

  11. Studyof Wastewater and Compost Effects on Some of Soil Physical and Chemical Characteristics

    Directory of Open Access Journals (Sweden)

    M. Shakarami

    2016-09-01

    Full Text Available Introduction: Arid and semi-arid areas are confronting increasing water shortages. In these regions of the world, planners are being forced to consider other water sources that could be used economically and effectively to promote further development. Wastewater is the only potential water source, which will increase as the population grows and the demand on freshwater increases. Composting municipal solid wastes (MSW and sewage sludge is a good way to reduce the amount of wastes generated in densely populated areas. Municipal solid waste production in Asia in 1998 was 0.76 million tons per day, with an annual growth rate of 2- 3% in developing countries and 3.2- 4.5% in developed countries. (MSW compost is increasingly used in agriculture not only as a soil conditioner but also as a fertilizer. Despite the growing interest in wastewater and compost usage, excessive application of them may have some harmful effects such as human health problems, runoff and leaching of nutrients to surface and groundwater, undesirable chemical constituents, pathogens, accumulations of heavy metals in plants and soils, negative environmental and health impacts. So, using of wastewater and compost application should be under controlled conditions that minimize health risks of agricultural products. Materials and Methods: This study was conducted in greenhouse of Bu-Ali Sina as a factorial completely randomized design to evaluate the effects of wastewater and compost on physical and chemical properties of soil. The factors included four types of watering: raw wastewater (W1, treated wastewater (W2 combined 50% of raw wastewater and fresh water (W3 and tap water (W4 and also four compost levels: 0 (C1, 40 (C2, 80 (C3 and 120 tha-1 (C4. Therefore, 16 treatments (W1C1 to W4C4 were considered for investigation. It is noted that Compost added and mixed just with top layer of the soil. 48 volumetric lysimeters were applied as Cultivation beds (26 × 30 × 30 cm. The soil

  12. Resilient modulus characteristics of soil subgrade with geopolymer additive in peat

    Science.gov (United States)

    Zain, Nasuhi; Hadiwardoyo, Sigit Pranowo; Rahayu, Wiwik

    2017-06-01

    Resilient modulus characteristics of peat soil are generally very low with high potential of deformation and low bearing capacity. The efforts to improve the peat subgrade resilient modulus characteristics is required, one among them is by adding the geopolymer additive. Geopolymer was made as an alternative to replace portland cement binder in the concrete mix in order to promote environmentally friendly, low shrinkage value, low creep value, and fire resistant material. The use of geopolymer to improve the mechanical properties of peat as a road construction subgrade, hence it becomes important to identify the effect of geopolymer addition on the resilient modulus characteristics of peat soil. This study investigated the addition of 0% - 20% geopolymer content on peat soil derived from Ogan Komering Ilir, South Sumatera Province. Resilient modulus measurement was performed by using cyclic triaxial test to determine the resilience modulus model as a function of deviator stresses and radial stresses. The test results showed that an increase in radial stresses did not necessarily lead to an increase in modulus resilient, and on the contrary, an increase in deviator stresses led to a decrease in modulus resilient. The addition of geopolymer in peat soil provided an insignificant effect on the increase of resilient modulus value.

  13. Physico-Chemical Characteristics of the Grassland Soils of Yusmarg Hill Resort (Kashmir, India

    Directory of Open Access Journals (Sweden)

    Moieza Ashraf

    2012-07-01

    Full Text Available Physico-chemical analysis was carried out on the grassland soils of Yusmarg Hill Resort, Kashmir during the months of May, June, November and December 2010, at four micro sites with some minor variations in the abiotic and biotic factors including anthropogenic pressures. The following soil characteristics were examined: temperature, texture, moisture, organic matter, pH, and conductivity, content of calcium, magnesium, sodium, potassium, total phosphorus, and organic carbon. Soil texture analysis revealed the soils at all the study sites with major proportion being comprised by the sand fraction and having a sandy silt character. The moisture content was found to be directly related to the herbaceous vegetation cover with the highest value at Site 3 (fenced meadow area. The moisture content showed low percentage at Site 2, which was more affected by grazing and thus resulted in less cover of grasses and probably more evaporation of soil moisture from the exposed site. The soils at all sites were from acidic to mildly acidic in character. The amount of organic matter was fairly good except at Site 2 (non-fenced grazing area probably due to overgrazing during which much of herbage vegetation was picked up by the grazing animals like sheep and cattle. The values of important cations, such as Ca2+ and Mg2+, showed a gradual decrease from May to December except at Site 4 (transition between a coniferous forest and a meadow which may be attributed to a good cover of vegetation and good amount of organic matter.

  14. Monitoring of Soil Chemical Characteristics with Time as Affected by Irrigation with Saline Water

    International Nuclear Information System (INIS)

    Mostafa, A.Z.; Galal, Y.G.M.; Lotfy, S.M.

    2015-01-01

    A lysimeter study was conducted to investigate the effect of irrigation with saline water on soil chemical characteristics at two depth (0-20) and (20-40 cm). Both fertilized (60, 120 Kg N/ha) and unfertilized (0) soil were simulated in a total of 84 lysimeter. Data indicated that the electric conductivity (EC) values tended to increase with time intervals also EC- values as affected by soil depth after 105 days were high in 20 cm depth as compared to 40 cm depth. Chloride concentration did not reflect great variations as affected by time of nitrogen application where the values were nearly closed to each other. At the end of the experiment, much of Cl- content was occurred in the second layer of soil depth (20-40) as compared to depth of 0-20 cm. This was the case under all salinity levels. The irrigation with fresh water did not reflect any significant different in EC values between 120 Kg N/ha, 60 Kg N/ha or soil depth, however, it tend to increase with increasing water salinity levels. There were no much differences between the nitrogen application time (T1, T2 and T3). In contrast with Cl-, sodium was remained in the upper layer of 0-20 cm soil depth but still increase with increasing water salinity levels.

  15. Monitoring of soil chemical characteristics with time as affected by irrigation with saline water

    International Nuclear Information System (INIS)

    Mostafa, A. Z.; Galal, Y.G.M.; Lotfy, S.M.

    2012-01-01

    A lysimeter study was conducted to investigate the effect of irrigation with saline water on soil chemical characteristics at two depth (0-20) and (20-40 cm).Both fertilized (60, 120 KgN/ha) and unfertilized (0) soil were simulated in a total of 84 lysimeter. Data indicated that the electric conductivity (EC) values tended to increase with time intervals also EC-values as affected by soil depth after 105 days were high in 20 cm depth as compared to 40 cm depth. Chloride concentration did not reflect great variations as affected by time of nitrogen application where the values were nearly closed to each other. At the end of the experiment, much of Cl - content was occurred in the second layer of soil depth (20-40) as compared to depth of 0-20 cm. This was the case under all salinity levels. The irrigation with fresh water did not reflect any significant different in EC values between 120 KgN/ha , 60 KgN/ha or soil depth, however, it tend to increase with increasing water salinity levels. There were no much differences between the nitrogen application time (T1, T2 and T3). In contrast with Cl - , sodium was remained in the upper layer of 0-20 cm soil depth but still increase with increasing water salinity levels.

  16. Characteristics of Volcanic Soils in Landslide during the 2016 Kumamoto Earthquake, Japan

    Science.gov (United States)

    Hazarika, H.; Fukuoka, H.; Kokusho, T.; Sumartini, O.; Bhoopendra, D.

    2017-12-01

    There were many seismic subsidence, debris flows, landslides and slope failures, which occurred in Aso area due to the 2016 Kumamoto earthquake, Japan. This research aims to determine the failure mechanism of many mild slopes, and elucidate the strength characteristics of volcanic soils collected from the sites. A series of undrained static and cyclic triaxial tests, ring shear tests and direct shear tests were performed. Also, for further understanding of volcanic soils' material strength, X-ray powder diffraction analysis (XRD), X-ray fluorescence analysis (XRF), and Scanning electron microscope analysis (SEM) were performed. In this paper, preliminary results of the experimental testing program are discussed.

  17. Environmentally Clean Mitigation of Undesirable Plant Life Using Lasers

    Energy Technology Data Exchange (ETDEWEB)

    Rubenchik, A M; McGrann, T J; Yamamoto, R M; Parker, J M

    2009-07-01

    This concept comprises a method for environmentally clean destruction of undesirable plant life using visible or infrared radiation. We believe that during the blossom stage, plant life is very sensitive to electromagnetic radiation, with an enhanced sensitivity to specific spectral ranges. Small doses of irradiation can arrest further plant growth, cause flower destruction or promote plant death. Surrounding plants, which are not in the blossoming stage, should not be affected. Our proposed mechanism to initiate this effect is radiation produced by a laser. Tender parts of the blossom possess enhanced absorptivity in some spectral ranges. This absorption can increase the local tissue temperature by several degrees, which is sufficient to induce bio-tissue damage. In some instances, the radiation may actually stimulate plant growth, as an alternative for use in increased crop production. This would be dependent on factors such as plant type, the wavelength of the laser radiation being used and the amount of the radiation dose. Practical, economically viable realization of this concept is possible today with the advent of high efficiency, compact and powerful laser diodes. The laser diodes provide an efficient, environmentally clean source of radiation at a variety of power levels and radiation wavelengths. Figure 1 shows the overall concept, with the laser diodes mounted on a movable platform, traversing and directing the laser radiation over a field of opium poppies.

  18. Preventing Undesirable Seismic Behaviour of Infill Walls in Design Process

    Directory of Open Access Journals (Sweden)

    Azadeh Noorifard

    2017-03-01

    Full Text Available Dividing walls are usually considered as non-structural elements, but experiences of past earthquakes show that some buildings designed and constructed by engineers have been damaged during earthquakes because of disregarding the negative effects of walls. Apart from the poor quality of construction and materials, inattention in design process is the main reason for undesirable seismic behaviour of walls.The main aim of this paper is to investigate the measures taken in different stages of architectural and structural design for improving the seismic behaviour of infilled concrete structures. As a general principle, with the further progress of project from basic architectural design to detailed structural design, there is a need to reduce designer authority and increase obligation, furthermore the cost of project increases too. The conclusion of this study implies that, in order to achieve the desirable seismic behaviour of walls, close collaboration between architects and structural engineers is required from the early stages of design. The results of this study are presented in a check list for designing reinforced concrete (RC moment resisting frame and RC shear wall.

  19. Analysis of soil characteristics, soil management and sugar yield on top and averagely managed farms growing sugar beet (Beta vulgaris L.) in the Netherlands

    NARCIS (Netherlands)

    Hanse, B.; Vermeulen, G.D.; Tijink, F.G.J.; Koch, H.J.; Märlander, B.

    2011-01-01

    Within the Speeding Up Sugar Yield (SUSY) project, soil management and soil characteristics were investigated as possible causes of yield differences in fields between 26 ‘type top’ and 26 ‘type average’ growers, ‘top’ and ‘average’ performance being based on past yield data. Growers were pairwise

  20. Improving the estimation of complete field soil water characteristic curves through field monitoring data

    Science.gov (United States)

    Bordoni, M.; Bittelli, M.; Valentino, R.; Chersich, S.; Meisina, C.

    2017-09-01

    In this work, Soil Water Characteristic Curves (SWCCs) were reconstructed through simultaneous field measurements of soil pore water pressure and water content. The objective was to evaluate whether field-based monitoring can allow for the improvement of the accuracy in SWCCs estimation with respect to the use of laboratory techniques. Moreover, field assessment of SWCCs allowed to: a) quantify the hydrological hysteresis affecting SWCCs through field data; b) analyze the effect of different temporal resolution of field measures; c) highlight the differences in SWCCs reconstructed for a particular soil during different hydrological years; d) evaluate the reliability of field reconstructed SWCCs, by the comparison between assessed and measured trends of a component of the soil water balance. These aspects were fundamental for assessing the reliability of the field reconstructed SWCCs. Field data at two Italian test-sites were measured. These test-sites were used to evaluate the goodness of field reconstructed SWCCs for soils characterized by different geomorphological, geological, physical and pedological features. Field measured or laboratory measured SWCCs data of 5 soil horizons (3 in a predominantly silty soil, 2 in a predominantly clayey one) were fitted by Van Genuchten model. Different field drying and wetting periods were identified, based on monthly meteorological conditions, in terms of rainfall and evapotranspiration amounts, of different cycles. This method allowed for a correct discrimination of the main drying and the main wetting paths from field data related and for a more reliable quantification of soil hydrological properties with respect to laboratory methodologies. Particular patterns of changes in SWCCs forms along depth could be also identified. Field SWCCs estimation is not affected by the temporal resolution of the acquisition (hours or days), as testified by similar values of Van Genuchten equation fitting parameters. Instead, hourly data

  1. The Characteristic and Genesis of Volcanic Ash Soil in the North Slope Toposequence of Kawi Mountain in Malang Regency

    Directory of Open Access Journals (Sweden)

    A.N. Putra

    2015-07-01

    Full Text Available The volcanic ash soil in Kawi Mountain is composed by the amorphous materials consist of allophane, imogolite and ferrihydrite. Results of previous study showed that the phosphate retention in all soil profiles of northern slope toposequence of Kawimountain was less than 85%, yet the phosphate retention of volcanic ash soils is usually > 85 %. This raised a question that there is a different characteristics of soil in the northern slope tosequence of the Kawi Mountain compared to the other places. This research was conducted to study soil characteristics, mineral contents, and genesis processessoccuring in soil on the northern slope toposequence of Kawi Mountain. 5 pedons between high elevation and low elevation (P1, P2, P3, P4 and P5 to identified the soil characteristics. The Al, Fe, and Si extracted by acid oxalate, natrium pyrophosphate, and dithionite citrate to calculate the amorphous mineral content. The results show that. The results showed that there is a different in terms of the thickness of the A horizon, the C organic content and the soil acidity level that mainly found in P3 and P4 profiles. The most important soil genesis processess in the formation of the volcanic ash soils were likely clay illuviation (P5, melanization and braunification (P3, littering (P1 and the reduction of andic soil properties from the upper slope (P1 profile up to the lower slope (P5 profile.

  2. Arsenic-containing soil from geogenic source in Hong Kong: Leaching characteristics and stabilization/solidification.

    Science.gov (United States)

    Li, Jiang-Shan; Beiyuan, Jingzi; Tsang, Daniel C W; Wang, Lei; Poon, Chi Sun; Li, Xiang-Dong; Fendorf, Scott

    2017-09-01

    Geogenic sources of arsenic (As) have aroused extensive environmental concerns in many countries. This study evaluated the vertical profiles, leaching characteristics, and surface characteristics of As-containing soils in Hong Kong. The results indicated that elevated levels of As (486-1985 mg kg -1 ) were mostly encountered in deeper layer (15-20 m below ground). Despite high concentrations, geogenic As displayed a high degree of chemical stability in the natural geochemical conditions, and there was minimal leaching of As in various leaching tests representing leachability, mobility, phytoavailability, and bioaccessibility. Microscopic/spectroscopic investigations suggested that As in the soils was predominantly present as As(V) in a coordination environment with Fe oxides. Sequential extraction indicated that the majority of As were strongly bound with crystalline Fe/Al oxides and residual phase. Yet, uncertainties may remain with potential As exposure through accidental ingestion and abiotic/biotic transformation due to changes in geochemical conditions. Hence, the effectiveness of stabilization/solidification (S/S) treatment was evaluated. Although the leached concentrations of As from the S/S treated soils increased to varying extent in different batch leaching tests due to the increase in alkalinity, the mobility of As was considered very low based on semi-dynamic leaching test. This suggested that As immobilization in the S/S treated soils was predominantly dependent on physical encapsulation by interlocking framework of hydration products, which could also prevent potential exposure and allow controlled utilization of S/S treated soils as monolithic materials. These results illustrate the importance of holistic assessment and treatment/management of As-containing soils for enabling flexible future land use. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Characteristics of soils in selected maize growing sites along altitudinal gradients in East African highlands

    Directory of Open Access Journals (Sweden)

    Elijah Njuguna

    2015-12-01

    Full Text Available Maize is the main staple crop in the East African Mountains. Understanding how the edaphic characteristics change along altitudinal gradients is important for maximizing maize production in East African Highlands, which are the key maize production areas in the region. This study evaluated and compared the levels of some macro and micro-elements (Al, Ca, Fe, K, Mg, Mn, Na and P and other soil parameters (pH, organic carbon content, soil texture [i.e. % Sand, % Clay and % Silt], cation exchange capacity [CEC], electric conductivity [EC], and water holding capacity [HC]. Soil samples were taken from maize plots along three altitudinal gradients in East African highlands (namely Machakos Hills, Taita Hills and Mount Kilimanjaro characterized by graded changes in climatic conditions. For all transects, pH, Ca, K and Mg decreased with the increase in altitude. In contrast, % Silt, organic carbon content, Al and water holding capacity (HC increased with increasing altitude. The research provides information on the status of the physical–chemical characteristics of soils along three altitudinal ranges of East African Highlands and includes data available for further research.

  4. Cycles of undesirable substances in the food chain; Kreislaeufe unerwuenschter Stoffe in der Lebensmittelkette

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2012-12-15

    The working group ''Carry over of undesirable substances in animal feed'' at the Federal Ministry of Food, Agriculture and Forestry (BMELV) in cooperation with the Institute of Animal Nutrition of the Friedrich-Loeffler-Institute (FLI) performed on 27 and 28 October 2011 in Braunschweig a workshop on ''cycles of undesirable substances in Food Chain ''. The aim of the workshop was to present the latest findings of research and Carry over Recommendations of the Carry over - Working Group on undesirable substances in feed and production processes of the feed industry, to evaluate and discuss about this with representatives from science, business and management and to work out the further research and action need. The focus of the considerations were the pathways, the carry over and the Exposure to dioxins and other halogenated hydrocarbons, the effects of Mycotoxins in feed and starting points for preventive measures, the soil contamination and the exposure of humans and animals by cadmium and case studies on Nitrite in feed, antibiotics in plants and residues of pesticides and radionuclides in feed. Furthermore the risks associated with specified manufacturing processes of feed are considered, especially the used materials that come into contact with animal feed, and the risks from nanotechnology. [German] Die Arbeitsgruppe ''Carry over unerwuenschter Stoffe in Futtermitteln'' beim Bundesministerium fuer Ernaehrung, Landwirtschaft und Forsten (BMELV) hat in Zusammenarbeit mit dem Institut fuer Tierernaehrung des Friedrich-Loeffler-Instituts (FLI) am 27. und 28. Oktober 2011 in Braunschweig einen Workshop zum Thema ''Kreislaeufe unerwuenschter Stoffe in der Lebensmittelkette'' durchgefuehrt. Ziel des Workshops war es, die aktuellen Erkenntnisse der Carry over Forschung und die Empfehlungen der Carry over - Arbeitsgruppe zu unerwuenschten Stoffen in Futtermitteln und Produktionsverfahren in

  5. Lead Contents and Distribution Characteristics of Soils and Vegetables Around an Abandoned Lead Smeltery

    Directory of Open Access Journals (Sweden)

    ZOU Tian-sen

    2016-07-01

    Full Text Available In order to disclose the degree and scope of lead pollution of the abandoned lead smeltery, 102 surface soil samples and 69 vegetables samples were collected by using the method of fan-shaped sampling points around an abandoned lead smeltery in Hubei Province. The lead contents of soils and vegetables were detected by graphite furnace atomic absorption spectrometry and inductively coupled plasma atomic emission spectrometry, respectively, and the lead spatial distribution was analyzed. The results showed that the geometric mean of lead contents in soils around the abandoned lead smeltery was 39.8 mg·kg-1 and exceeded the soil background value of Hubei Province(26.7 mg·kg-1. The mean value of geo-accumulation indexes of lead contents in soil was 0.09, and 36.4% of them exceeded zero. The geo-accumulation indexes of sampling distance of 500, 1000 m and 1500 m from the smeltery were 2.11, 0.61 and 0.33, respectively, while the values of sampling distances of more than 2000 m were all less than zero. 24.0%、36.0% and 6.3% of the lead contents exceeded the standard value of limited standards of contaminants in vagetables for cabbage, radish and green onion samples, respectively. The soils and vegetables around the abandonded lead smeltery within 500 m were contaminated seriously. The degree of lead pollution in soils was mild or moderate within 500 m to 2000 m, and the maximum scope in cabbage, radish and green onion was polluted within 500~1000, 1000~1500 m and 500~1000 m, respectively. Lead pollution in vegetables around the abandonded lead smeltery presented obvious characteristics of high pollution and enrichment.

  6. Changes in soil characteristics and C dynamics after mangrove clearing (Vietnam).

    Science.gov (United States)

    Grellier, Séraphine; Janeau, Jean-Louis; Dang Hoai, Nhon; Nguyen Thi Kim, Cuc; Le Thi Phuong, Quynh; Pham Thi Thu, Thao; Tran-Thi, Nhu-Trang; Marchand, Cyril

    2017-09-01

    Of the blue carbon sinks, mangroves have one of the highest organic matter (OM) storage capacities in their soil due to low mineralization processes resulting from waterlogging. However, mangroves are disappearing worldwide because of demographic increases. In addition to the loss of CO 2 fixation, mangrove clearing can strongly affect soil characteristics and C storage. The objectives of the present study were to quantify the evolution of soil quality, carbon stocks and carbon fluxes after mangrove clearing. Sediment cores to assess physico-chemical properties were collected and in situ CO 2 fluxes were measured at the soil-air interface in a mangrove of Northern Vietnam. We compared a Kandelia candel mangrove forest with a nearby zone that had been cleared two years before the study. Significant decrease of clay content and an increase in bulk density for the upper 35cm in the cleared zone were observed. Soil organic carbon (OC) content in the upper 35cm decreased by >65% two years after clearing. The quantity and the quality of the carbon changed, with lower carbon to nitrogen ratios, indicating a more decomposed OM, a higher content of dissolved organic carbon, and a higher content of inorganic carbon (three times higher). This highlights the efficiency of mineralization processes following clearing. Due to the rapid decrease in the soil carbon content, CO 2 fluxes at sediment interface were >50% lower in the cleared zone. Taking into account carbonate precipitation after OC mineralization, the mangrove soil lost ~10MgOCha -1 yr -1 mostly as CO 2 to the atmosphere and possibly as dissolved forms towards adjacent ecosystems. The impacts on the carbon cycle of mangrove clearing as shown by the switch from a C sink to a C source highlight the importance of maintaining these ecosystems, particularly in a context of climate change. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Morphological, sediment and soil chemical characteristics of dry tropical shallow reservoirs in the Southern Mexican Highlands

    Directory of Open Access Journals (Sweden)

    José Luis ARREDONDO-FIGUEROA

    2011-02-01

    Full Text Available The morphometry, sediment and soil chemical characteristics of eleven dry tropical shallow reservoirs situated in Southern Mexican Highlands were studied. The reservoirs are located at 1104 to 1183 meters above sea level in a sedimentary area. Seventeen morphometric and eight sediment and soil chemical parameters were measured. The results of the morphometric parameters showed that these reservoirs presented a soft and roughness bottom, with an ellipsoid form and a concave depression that permit the mix up of water and sediments, causing turbidity and broken thermal gradients; their slight slopes allowed the colonization of submerged macrophyte and halophyte plants and improved the incidence of sunlight on water surface increasing evaporation and primary productivity. Dry tropical shallow reservoirs have fluctuations in area, and volume according to the amount of rainfall, the effect of evaporation, temperature, lost volume for irrigation, and other causes. The sand-clay was the most important sediment texture and their values fluctuated with the flooded periods. The concentration-dilution cycle showed a direct relationship in the percentage of organic matter in the soil as well as with pH, soil nitrogen and phosphorus. El Tilzate, El Candelero and El Movil were related by the shore development and high concentrations of organic matter and nitrogen in the soil. Finally, we emphasize the importance of this study, in relation to possible future changes in morphometrical parameters as a consequence of human impact.

  8. [Degradation characteristics of transgenic cotton residues in soil by Fourier transform infrared spectroscopy].

    Science.gov (United States)

    Chen, Zhen-Hua; Zhang, Yu-Lan; Jia, Yin-Hua; Chen, Li-Jun; Liu, Xing-Bin; Wu, Zhi-Jie

    2011-01-01

    After transgenic cotton residues incubated in soil 430 d, the contents and structural characteristics of soil humus fractions, fulvic acid, humic acid and humin were measured by potassium dichromate titrimetric method and Fourier transform infrared spectroscopy. The results showed that all soil humus fractions increased after the degradation of cotton residues, and the most relative increase was with humin and the least was with fulvic acid. Compared to their near-isogenic non-transgenic cottons, soil humus content for transgenic Bt cotton residue decreased, and that forr transgenic Bt+CpTI cotton Z41 was approximate, but that for transgenic Bt+CpTI cotton SGK321 increased. Infrared spectroscopy of fulvic acid, humic acid and humin showed the addition of cotton residue decreased the content of oxygenous groups, and increased the alkyl and amide groups. There were differences in the speed to form soil humus among three transgenic cottons. Transgenic Bt cotton was slower than its counterpart, transgenic Bt+CpTI cotton Z41 was approximate to its counterpart, but transgenic Bt+CpTI cotton SGK321 was faster than its counterpart.

  9. Leaching characteristics of residual lateritic soils stabilised with fly ash and lime for geotechnical applications.

    Science.gov (United States)

    Goswami, R K; Mahanta, C

    2007-01-01

    The effective use of residual lateritic soils as fill material for various construction activities is often limited by the difficulty in handling them. Attempt to improve their workability with fly ash and lime has shown promising results, although accompanied by risk of release of heavy metal leachates to the groundwater. In the present work, the leaching properties from residual lateritic soils from a part of Northeast India stabilised with fly ash and lime (CaO) was investigated with the help of single batch leaching test and column leaching test for different soil-fly ash-lime mixes. Test results show that the high pH induced by lime treatment of the mixes helps in keeping most of the metals within the stabilised soil matrix. Although the heavy metal concentrations in the leachates were generally within permissible limits, the release response for different metals was different suggesting implications for permeate solutions having metal pre-concentrations, such as those emanating from hazardous landfill sites. The observed characteristics provide insights towards the potential and realistic estimates of leaching of metals and its variation due to change in fly ash and lime content in the stabilised mix. Many of these constituents found in the stabilised soil had a first-flush phenomenon. But, as they occur only for short duration (about 5 pore volumes over 5 days) and at low concentration, dilution effect may eliminate them. The effect of continuous permeation on the flow parameters and the leaching pattern of the mixes have also been highlighted.

  10. The Relation between Soil Parameters and Growth Characteristics of Tamarix ramosissima in Abyaneh, Isfahan Province

    Directory of Open Access Journals (Sweden)

    SayedHamid Matinkhah

    2017-12-01

    Full Text Available Vegetative characteristics of plant species are strongly dependent on habitat environmental conditions. Most Salt cedar (Tamarix ramosissima individuals grow on unsuitable soil and climate conditions. One of the important habitats of this species is near Abyaneh in Isfahan Province. To investigate the relation of edaphic factors on the growth of T. ramosissima, three plots 400m2 in area were randomly placed in this region. In each plot, crown cover and mean height of each tree were measured. Chemical and physical properties of soil were evaluated in two depths (0-20, 20-40cm. The relation between soil and vegetation was assessed using ordination method and RDA. The results suggest that in the upper depth, organic matter and saturation percentage (%SP have a strong positive correlation with vegetative factors of T. ramosissima including canopy cover and mean height. On the other hand, in lower depth pH, %CaSO4 factors have higher correlation with plants factors compared to upper depth. Therefore, organic matter in upper layer and saturation percentage (%SP have more correlation with vegetative factors. This suggests the importance of studying these two soil depths. In the restoration projects on this species, it is necessary to consider the abovementioned soil factors.

  11. Investigation of the soil characteristics for coastal zone land-use planning, Kandira, Izmit

    Directory of Open Access Journals (Sweden)

    T. Fikret Kurnaz

    2017-10-01

    Full Text Available It is necessary to perform detailed soil investigations for reliable constructions in settlement areas which have a suitable topography for natural disasters such as earthquake, landslide etc. The regional and parcel-based ground surveys have great importance especially for the earthquake resistant building design in new settlement areas and the revision of the existing settlement areas. Presentation of soil properties and analysis results with zoning maps in the surveys for land use planning, contributes to the determination of risky and safe areas in terms of settlement. In this study, the soil characteristics of the study area were investigated by geological, geophysical and geotechnical studies results and the settlement suitability was evaluated with the zonation maps. The dominant geological unit in the region is Quaternary aged alluvium and on the hillsides near the seaside are covered by Upper Cretaceous aged micritic limestones belonging to Akveren Formation. 13 drilling, 15 seismic refraction, 10 MASW, 7 mikrotremor studies and results of the laboratory tests have been used for the evaluation of the soil properties in the study area. The local soil classes were determined as Z4 in the alluvium and Z2 in the limestones. The limestone strengths in the region were determined as low and middle. The hilly areas located in the west and east of the study area belonging to Akveren Formation have karstic cavities and 40% slope. These areas are not suitable for settlement.

  12. Improvement of Soil Biology Characteristics at Paddy Field by System of Rice Intensification

    Directory of Open Access Journals (Sweden)

    Widyatmani Sih Dewi

    2015-07-01

    Full Text Available The aim of the research was to test the System of Rice Intensification (SRI method in improving the biological properties of paddy soil. The indicators of improvement were measured by the number of earthworm feces (cast, and the population of some microbial and nutrient content in the cast. The experiments were performed by comparing the three methods, namely: (1 SRI, (2 semi-conventional, and (3 conventional, using Randomized Completely Block Design. Each treatment was repeated nine times. The experiments were performed in the paddy fields belonging to farmers in Sukoharjo, Central Java. The result showed that the SRI (application of 1 tons ha-1 of vermicompost + 50% of inorganic fertilizer dosage tends to increase the number of earthworms cast. It is an indicator of earthworm activity in soil. Earthworms cast contains more phosphate solubilizing bacteria (12.98 x 1010cfu and N content (1.23% compared to its surrounding soil. There is a close functional relation between earthworms cast with total tiller number. SRI method is better than the other two methods to improve the biological characteristics of paddy soil that has the potential to maintain the sustainability of soil productivity.

  13. Research into action of surface soil moistening, drying or freezing on electrical characteristics of grounding device

    Directory of Open Access Journals (Sweden)

    I.V. Nizhevskiy

    2014-03-01

    Full Text Available The analysis made has shown expediency of modernization rather than reconstruction of earth electrodes, after inspection of long operating substations grounding grids, via building a two-level structure. It will result in both technical and economic effects. The novelty of the results consists in studying, by means of a mathematical model, electrical characteristics of a two-level earth electrode versus the depth of surface soil drying or freezing.

  14. Damping characteristic identification of non-linear soil-structural system interaction by phase resonance

    International Nuclear Information System (INIS)

    Poterasu, V.F.

    1984-01-01

    It is presented a method and the phase resonance for damping characteristic identification of non-linear soil-structural interaction. The algorithm can be applied in case of any, not necessarily, damping characteristic of the system examined. For the identification, the system is harmonically excited and are considered the super-harmonic amplitudes for odd and even powers of the x. The response of shear beam system for different levels of base excitation and for different locations of the load is considered. (Author) [pt

  15. [Distribution and accumulation characteristics of nutrients in solar greenhouse soil in Ji'nan, Shandong Province of East China].

    Science.gov (United States)

    Cao, Qi-Wei; Zhang, Wei-Hua; Li, Li-Bin; Sun, Yu-Liang; Sun, Xiao-Lei; Ai, Xi-Zhen

    2012-01-01

    Taking the solar greenhouses with different cultivating years and vegetables in Ji'nan as test objects, this paper studied the amounts and frequency distribution of soil nutrients and the relationships between cultivating years and soil nutrients accumulation characteristics, and analyzed the factors causing soil salinization and acidification by fitting soil nutrients contents with cultivating years and vegetables. In the greenhouses, the contents of soil alkali-hydrolysable nitrogen, available phosphorus, available potassium, organic matter, and electrical conductivity were significantly higher than those in the open field, with an increment of 135.3%, 475.2%, 290.1%, 97.7%, and 188.7%, respectively, but the soil pH value was 0.31 lower than that of open field. The frequency distribution of soil nutrients presented a normal curve. Differences were observed in the soil nutrients contents in the greenhouses with different cultivating vegetables. The soil alkali-hydrolysable nitrogen content and electrical conductivity were in the order of tomato > cucumber > sweet pepper, soil organic matter content and pH value were cucumber > sweet pepper > tomato, soil available phosphorus content was cucumber > tomato > sweet pepper, and soil available potassium content was tomato > cucumber > sweet pepper. There was a mild tendency of soil acidification in soil alkali-hydrolysable nitrogen and available potassium. The decrease of soil pH was closely related to the accumulation of alkali-hydrolysable nitrogen. The soil nutrients accumulation in the greenhouses had the similar patterns, i. e. , rapid accumulation in the first two cultivating years, slowed down in the third and fourth year, and kept stable later, demonstrating a dynamic balance on the whole. All the nutrients contents were positively accumulated, while soil pH presented negatively. In the greenhouses with different cultivating vegetables, there was a significant correlation between soil nutrients and cultivating

  16. Physics of the Soil Medium OrganizationPart 2: Pedostructure Characterization through Measurement and Modeling of the Soil Moisture Characteristic Curves

    Directory of Open Access Journals (Sweden)

    AMJAD TAYSEER ASSI

    2014-03-01

    Full Text Available Accurate measurement of the two soil moisture characteristic curves, namely, water retention curve (WRC and soil shrinkage curve (SSC is fundamental for the physical modeling of hydrostructural processes in vadose zone. This paper is the application part following the theory presented in part I about physics of soil medium organization. Two native Aridisols in the state of Qatar named locally Rodah räôd´ə soil and Sabkha săb′kə soil were studied. The paper concluded two main results: the first one is about the importance of having continuous and simultaneous measurement of soil water content, water potential and volume change. Such measurement is imperative for accurate and consistent characterization of each of the two moisture characteristic curves, and consequently the hydrostructural properties of the soil medium. The second is about the simplicity, reliability, strength and uniqueness of identifying the characteristic parameters of the two curves. The results also confirmed the validity of the thermodynamic-based equations of the two characteristic curves presented in part I.

  17. Potential Phosphorus Mobilisation in Peat Soils

    DEFF Research Database (Denmark)

    Forsmann, Ditte M.; Kjærgaard, Charlotte

    2012-01-01

    peat soils before a re-establishment takes place. The potential phosphorus mobilisation from a peat soil depends not only on the geochemical characteristics but also on the redox conditions, the hydrological regime in the area as well as the hydro-physical properties of the soil. The hypothesis...... on intact soil samples from each of the 10 locations. As a result the geochemical key parameters controlling the potential phosphorus release from peat soils has been pointed out. Furthermore, it has been emphasised how much the hydro-physical properties influence the potential phosphorus mobilisation from......Re-establishment of wetlands on peat soils containing phosphorus bound to iron(III)-oxides can lead to an undesirable phosphorus loss to the aquatic environment due to the reductive dissolution of iron(III)-oxides. Thus it is important to be able to assess the potential phosphorus mobilisation from...

  18. Biochar Effect on Maize Yield and Soil Characteristics in Five Conservation Farming Sites in Zambia

    Directory of Open Access Journals (Sweden)

    Alfred Obia

    2013-04-01

    Full Text Available Biochar addition to agricultural soils can improve soil fertility, with the added bonus of climate change mitigation through carbon sequestration. Conservation farming (CF is precision farming, often combining minimum tillage, crop rotation and residue retention. In the present farmer-led field trials carried out in Zambia, the use of a low dosage biochar combined with CF minimum tillage was tested as a way to increase crop yields. Using CF minimum tillage allows the biochar to be applied to the area where most of the plant roots are present and mirrors the fertilizer application in CF practices. The CF practice used comprised manually hoe-dug planting 10-L sized basins, where 10%–12% of the land was tilled. Pilot trials were performed with maize cob biochar and wood biochar on five soils with variable physical/chemical characteristics. At a dosage as low as 4 tons/ha, both biochars had a strong positive effect on maize yields in the coarse white aeolian sand of Kaoma, West-Zambia, with yields of 444% ± 114% (p = 0.06 and 352% ± 139% (p = 0.1 of the fertilized reference plots for maize and wood biochar, respectively. Thus for sandy acidic soils, CF and biochar amendment can be a promising combination for increasing harvest yield. Moderate but non-significant effects on yields were observed for maize and wood biochar in a red sandy clay loam ultisol east of Lusaka, central Zambia (University of Zambia, UNZA, site with growth of 142% ± 42% (p > 0.2 and 131% ± 62% (p > 0.2 of fertilized reference plots, respectively. For three other soils (acidic and neutral clay loams and silty clay with variable cation exchange capacity, CEC, no significant effects on maize yields were observed (p > 0.2. In laboratory trials, 5% of the two biochars were added to the soil samples in order to study the effect of the biochar on physical and chemical soil characteristics. The large increase in crop yield in Kaoma soil was tentatively explained by a combination

  19. Biochar effect on maize yield and soil characteristics in five conservation farming sites in Zambia

    Science.gov (United States)

    Cornelissen, Gerard; Martinsen, Vegard; Shitumbanuma, Victor; Alling, Vanja; Breedveld, Gijs D.; Rutherford, David W.; Sparrevik, Magnus; Hale, Sarah E.; Obia, Alfred; Mulder, Jan

    2013-01-01

    Biochar addition to agricultural soils can improve soil fertility, with the added bonus of climate change mitigation through carbon sequestration. Conservation farming (CF) is precision farming, often combining minimum tillage, crop rotation and residue retention. In the present farmer-led field trials carried out in Zambia, the use of a low dosage biochar combined with CF minimum tillage was tested as a way to increase crop yields. Using CF minimum tillage allows the biochar to be applied to the area where most of the plant roots are present and mirrors the fertilizer application in CF practices. The CF practice used comprised manually hoe-dug planting 10-L sized basins, where 10%–12% of the land was tilled. Pilot trials were performed with maize cob biochar and wood biochar on five soils with variable physical/chemical characteristics. At a dosage as low as 4 tons/ha, both biochars had a strong positive effect on maize yields in the coarse white aeolian sand of Kaoma, West-Zambia, with yields of 444% ± 114% (p = 0.06) and 352% ± 139% (p = 0.1) of the fertilized reference plots for maize and wood biochar, respectively. Thus for sandy acidic soils, CF and biochar amendment can be a promising combination for increasing harvest yield. Moderate but non-significant effects on yields were observed for maize and wood biochar in a red sandy clay loam ultisol east of Lusaka, central Zambia (University of Zambia, UNZA, site) with growth of 142% ± 42% (p > 0.2) and 131% ± 62% (p > 0.2) of fertilized reference plots, respectively. For three other soils (acidic and neutral clay loams and silty clay with variable cation exchange capacity, CEC), no significant effects on maize yields were observed (p > 0.2). In laboratory trials, 5% of the two biochars were added to the soil samples in order to study the effect of the biochar on physical and chemical soil characteristics. The large increase in crop yield in Kaoma soil was tentatively explained by a combination of an

  20. Biochar effect on maize yield and soil characteristics in five conservation farming sites in Zambia

    Science.gov (United States)

    Cornelissen, Gerard; Martinsen, Vegard; Shitumbanuma, Victor; Alling, Vanja; Breedveld, Gijs D.; Rutherford, David W.; Sparrevik, Magnus; Hale, Sarah E.; Obia, Alfred; Mulder, Jan

    2013-01-01

    Biochar addition to agricultural soils can improve soil fertility, with the added bonus of climate change mitigation through carbon sequestration. Conservation farming (CF) is precision farming, often combining minimum tillage, crop rotation and residue retention. In the present farmer-led field trials carried out in Zambia, the use of a low dosage biochar combined with CF minimum tillage was tested as a way to increase crop yields. Using CF minimum tillage allows the biochar to be applied to the area where most of the plant roots are present and mirrors the fertilizer application in CF practices. The CF practice used comprised manually hoe-dug planting 10-L sized basins, where 10%–12% of the land was tilled. Pilot trials were performed with maize cob biochar and wood biochar on five soils with variable physical/chemical characteristics. At a dosage as low as 4 tons/ha, both biochars had a strong positive effect on maize yields in the coarse white aeolian sand of Kaoma, West-Zambia, with yields of 444% ± 114% (p = 0.06) and 352% ± 139% (p = 0.1) of the fertilized reference plots for maize and wood biochar, respectively. Thus for sandy acidic soils, CF and biochar amendment can be a promising combination for increasing harvest yield. Moderate but non-significant effects on yields were observed for maize and wood biochar in a red sandy clay loam ultisol east of Lusaka, central Zambia (University of Zambia, UNZA, site) with growth of 142% ± 42% (p > 0.2) and 131% ± 62% (p > 0.2) of fertilized reference plots, respectively. For three other soils (acidic and neutral clay loams and silty clay with variable cation exchange capacity, CEC), no significant effects on maize yields were observed (p > 0.2). In laboratory trials, 5% of the two biochars were added to the soil samples in order to study the effect of the biochar on physical and chemical soil characteristics. The large increase in crop yield in Kaoma soil was tentatively explained by a combination of an

  1. To Evaluate the Effect of Soil Physical and Chemical Characteristics on the Growth Characteristics of Saffron (Crocus sativus L. Corms in Tornbat-e Heydariyeh Area

    Directory of Open Access Journals (Sweden)

    Fariba Zarghani

    2016-07-01

    Full Text Available Introduction Saffron is one of the most economically important plants across Iran and all over the world. The most important cultivated areas of saffron are in Khorasan-e Razavi and Southern Khorasan provinces (Jihad Keshavarzi Khorasan Razavi, 2013. The corm is the reservoir of photosynthetic materials and plays an important role in the saffron life cycle. Corm size and physicochemical characteristics of soil determine the growth and yield of saffron (Aytekin et al., 2008. It has been advised to use corms with diameter more than 2.5 cm (Kafi et al., 2002. Despite the importance of this plant, few studies have been conducted on the effects of soil characteristics on the growth of the plant in natural field conditions. Therefore, the objective which we will try to achieve is: to evaluate the effect of soil physical and chemical characteristics of the growth of saffron corm and determine the most important effect characteristics. Materials and methods In September 2012, 30 samples of 3 to 5 years old saffron corms were taken from the fields with similar management in Torbat Heydariyeh. The surrounding soil corms (depth of 0 to 30 cm were sampled, too. Dry weight of corms was measured in the laboratory. Air dried soil samples were passed through a 2 mm sieve and used for physical-chemical analyses. Soil texture was determined by using pipet method. Total nitrogen, available phosphorous, available potassium, soil organic carbon and calcium carbonate equivalent were measured in bulk soil samples. Calcium, magnesium, sodium, EC and pH were measured in the saturated soil paste. Fe, Cu and Zn were extracted by DTPA and measured by atomic adsorption spectroscopy. Correlation, regression and neural network technique were used to analyze the data and to identify the most important soil characteristics on the corms characteristics. Results and discussion Diameter and dry weight of corms with mean values of 34.04 mm and 3.72 g, ranged from 22.8 to 51.7 mm

  2. 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...

  3. A review of the distribution coefficients of trace elements in soils: influence of sorption system, element characteristics, and soil colloidal properties.

    Science.gov (United States)

    Shaheen, Sabry M; Tsadilas, Christos D; Rinklebe, Jörg

    2013-12-01

    Knowledge about the behavior and reactions of separate soil components with trace elements (TEs) and their distribution coefficients (Kds) in soils is a key issue in assessing the mobility and retention of TEs. Thus, the fate of TEs and the toxic risk they pose depend crucially on their Kd in soil. This article reviews the Kd of TEs in soils as affected by the sorption system, element characteristics, and soil colloidal properties. The sorption mechanism, determining factors, favorable conditions, and competitive ions on the sorption and Kd of TEs are also discussed here. This review demonstrates that the Kd value of TEs does not only depend on inorganic and organic soil constituents, but also on the nature and characteristics of the elements involved as well as on their competition for sorption sites. The Kd value of TEs is mainly affected by individual or competitive sorption systems. Generally, the sorption in competitive systems is lower than in mono-metal sorption systems. More strongly sorbed elements, such as Pb and Cu, are less affected by competition than mobile elements, such as Cd, Ni, and Zn. The sorption preference exhibited by soils for elements over others may be due to: (i) the hydrolysis constant, (ii) the atomic weight, (iii) the ionic radius, and subsequently the hydrated radius, and (iv) its Misono softness value. Moreover, element concentrations in the test solution mainly affect the Kd values. Mostly, values of Kd decrease as the concentration of the included cation increases in the test solution. Additionally, the Kd of TEs is controlled by the sorption characteristics of soils, such as pH, clay minerals, soil organic matter, Fe and Mn oxides, and calcium carbonate. However, more research is required to verify the practical utilization of studying Kd of TEs in soils as a reliable indicator for assessing the remediation process of toxic metals in soils and waters. © 2013 Elsevier B.V. All rights reserved.

  4. Investigating the Effect of Compaction Characteristics on the Erodibility of Cohesive Soils Using the JET Method

    Science.gov (United States)

    Asghari Tabrizi, A.; LaRocque, L. A.; Chaudhry, M.; Imran, J.

    2013-12-01

    Several flood disasters occur every year all over the world, mostly due to levee and dam failure which result in human fatalities as well as devastating economic damages. To model and predict earthen embankment failures for the preparation of emergency action plans and risk assessments, the soil erodibility by flowing water is an essential parameter. The determination of erodibility becomes even more complicated for cohesive soils because of the large number of parameters controlling their erosion behavior (e.g. clay content, plasticity, compaction effort, compaction water content) and the difficulty of estimating these parameters. In this study the effect of the compaction energy and compaction water content on the erodibility of a sandy loam soil was assessed. Soil samples were prepared in a standard diameter compaction mold, 101.6 mm, for three levels of compaction effort and water content (i.e. low, medium, and high) with two replications for each case (18 tests total) and examined using the jet erosion test (JET). Observations from qualitative and statistical analyses of the data are: 1) a wide range of erodibility, from very erodible to very resistant, was produced by changes in the compaction characteristics; 2) for a given compaction energy, the erosion resistance based on the detachment rate coefficient kd tends to become minimum near the optimum compaction water content. On the dry side of optimum compaction water content, kd decreases with steep gradients by increasing the water content, while it increases with a flatter gradient on the wet side; 3) At a given water content, the soil erosion resistance increases with compaction efforts; 4) compaction water content influences soil erosibility more than compaction energy, especially on the dry side of the optimum compaction water content; and 5) for a given compaction effort, the critical shear stress increases with water content up to an optimum water content and then it decreases which is in consistent

  5. Fractal Characteristics of Soil Retention Curve and Particle Size Distribution with Different Vegetation Types in Mountain Areas of Northern China

    Science.gov (United States)

    Niu, Xiang; Gao, Peng; Wang, Bing; Liu, Yu

    2015-01-01

    Based on fractal theory, the fractal characteristics of soil particle size distribution (PSD) and soil water retention curve (WRC) under the five vegetation types were studied in the mountainous land of Northern China. Results showed that: (1) the fractal parameters of soil PSD and soil WRC varied greatly under each different vegetation type, with Quercus acutissima Carr. and Robina pseudoacacia Linn. mixed plantation (QRM) > Pinus thunbergii Parl. and Pistacia chinensis Bunge mixed plantation (PPM) > Pinus thunbergii Parl. (PTP) > Juglans rigia Linn. (JRL) > abandoned grassland (ABG); (2) the soil fractal dimensions of woodlands (QRM, PPM, PTP and JRL) were significantly higher than that in ABG, and mixed forests (QRM and PPM) were higher than that in pure forests (PTP and JRL); (3) the fractal dimension of soil was positively correlated with the silt and clay content but negatively correlated with the sand content; and (4) the fractal dimension of soil PSD was positively correlated with the soil WRC. These indicated that the fractal parameters of soil PSD and soil WRC could act as quantitative indices to reflect the physical properties of the soil, and could be used to describe the influences of the Return Farmland to Forests Projects on soil structure. PMID:26633458

  6. Fractal Characteristics of Soil Retention Curve and Particle Size Distribution with Different Vegetation Types in Mountain Areas of Northern China

    Directory of Open Access Journals (Sweden)

    Xiang Niu

    2015-12-01

    Full Text Available Based on fractal theory, the fractal characteristics of soil particle size distribution (PSD and soil water retention curve (WRC under the five vegetation types were studied in the mountainous land of Northern China. Results showed that: (1 the fractal parameters of soil PSD and soil WRC varied greatly under each different vegetation type, with Quercus acutissima Carr. and Robina pseudoacacia Linn. mixed plantation (QRM > Pinus thunbergii Parl. and Pistacia chinensis Bunge mixed plantation (PPM > Pinus thunbergii Parl. (PTP > Juglans rigia Linn. (JRL > abandoned grassland (ABG; (2 the soil fractal dimensions of woodlands (QRM, PPM, PTP and JRL were significantly higher than that in ABG, and mixed forests (QRM and PPM were higher than that in pure forests (PTP and JRL; (3 the fractal dimension of soil was positively correlated with the silt and clay content but negatively correlated with the sand content; and (4 the fractal dimension of soil PSD was positively correlated with the soil WRC. These indicated that the fractal parameters of soil PSD and soil WRC could act as quantitative indices to reflect the physical properties of the soil, and could be used to describe the influences of the Return Farmland to Forests Projects on soil structure.

  7. Fractal Characteristics of Soil Retention Curve and Particle Size Distribution with Different Vegetation Types in Mountain Areas of Northern China.

    Science.gov (United States)

    Niu, Xiang; Gao, Peng; Wang, Bing; Liu, Yu

    2015-12-03

    Based on fractal theory, the fractal characteristics of soil particle size distribution (PSD) and soil water retention curve (WRC) under the five vegetation types were studied in the mountainous land of Northern China. Results showed that: (1) the fractal parameters of soil PSD and soil WRC varied greatly under each different vegetation type, with Quercus acutissima Carr. and Robina pseudoacacia Linn. mixed plantation (QRM) > Pinus thunbergii Parl. and Pistacia chinensis Bunge mixed plantation (PPM) > Pinus thunbergii Parl. (PTP) > Juglans rigia Linn. (JRL) > abandoned grassland (ABG); (2) the soil fractal dimensions of woodlands (QRM, PPM, PTP and JRL) were significantly higher than that in ABG, and mixed forests (QRM and PPM) were higher than that in pure forests (PTP and JRL); (3) the fractal dimension of soil was positively correlated with the silt and clay content but negatively correlated with the sand content; and (4) the fractal dimension of soil PSD was positively correlated with the soil WRC. These indicated that the fractal parameters of soil PSD and soil WRC could act as quantitative indices to reflect the physical properties of the soil, and could be used to describe the influences of the Return Farmland to Forests Projects on soil structure.

  8. Time evolution of the general characteristics and Cu retention capacity in an acid soil amended with a bentonite winery waste

    DEFF Research Database (Denmark)

    Fernandez Calviño, David; Rodríguez-Salgado, Isabel; Pérez-Rodríguez, Paula

    2015-01-01

    The effect of bentonite waste added to a "poor" soil on its general characteristic and copper adsorption capacity was assessed. The soil was amended with different bentonite waste concentrations (0, 10, 20, 40 and 80Mgha-1) in laboratory pots, and different times of incubation of samples were...... tested (one day and one, four and eight months). The addition of bentonite waste increased the pH, organic matter content and phosphorus and potassium concentrations in the soil, being stable for P and K, whereas the organic matter decreased with time. Additionally, the copper sorption capacity...... of the soil and the energy of the Cu bonds increased with bentonite waste additions. However, the use of this type of waste in soil presented important drawbacks for waste dosages higher than 20Mgha-1, such as an excessive increase of the soil pH and an increase of copper in the soil solution....

  9. Evaluation of soil characteristics potentially affecting arsenic concentration in paddy rice (Oryza sativa L.)

    Energy Technology Data Exchange (ETDEWEB)

    Bogdan, Katja, E-mail: katja.bogdan@pflern.uni-hannover.d [Institute of Plant Nutrition, Leibniz Universitaet Hannover, Herrenhaeuser Str. 2, 30419 Hannover (Germany); Schenk, Manfred K., E-mail: schenk@pflern.uni-hannover.d [Institute of Plant Nutrition, Leibniz Universitaet Hannover, Herrenhaeuser Str. 2, 30419 Hannover (Germany)

    2009-10-15

    Paddy rice may contribute considerably to the human intake of As. The knowledge of soil characteristics affecting the As content of the rice plant enables the development of agricultural measures for controlling As uptake. During field surveys in 2004 and 2006, plant samples from 68 fields (Italy, Po-area) revealed markedly differing As concentration in polished rice. The soil factors total As{sub (aquaregia)}, pH, grain size fractions, total C, plant available P{sub (CAL)}, poorly crystalline Fe{sub (oxal.)} and plant available Si{sub (Na-acetate)} content that potentially affect As content of rice were determined. A multiple linear regression analysis showed a significant positive influence of the total As{sub (aquaregia)} and plant available P{sub (CAL)} content and a negative influence of the poorly crystalline Fe{sub (oxal.)} content of the soil on the As content in polished rice and rice straw. Si concentration in rice straw varied widely and was negatively related to As content in straw and polished rice. - Field selection for total As, poorly crystalline Fe and plant available P in soil might contribute to control As content of paddy rice.

  10. A methodological framework to determine optimum durations for the construction of soil water characteristic curves using centrifugation

    NARCIS (Netherlands)

    Vero, Sara E.; Healy, Mark G.; Henry, Tiernan; Creamer, Rachel E.; Ibrahim, Tristan G.; Forrestal, Patrick J.; Richards, Karl G.; Fenton, Owen

    2016-01-01

    During laboratory assessment of the soil water characteristic curve (SWCC), determining equilibrium at various pressures is challenging. This study establishes a methodological framework to identify appropriate experimental duration at each pressure step for the construction of SWCCs via

  11. [Carbon and nitrogen distributions and microbial characteristics in the soils of four types of wetlands in Sanjiang Plain, Northeast China].

    Science.gov (United States)

    2014-10-01

    Four typical wetlands in the Honghe Wetland Reserve of Sanjiang Plain (i. e. wetlands with the following dominant plant species: Calamagrostis angustifolia + Salix brachypoda, Calamagrostis angustifolia, Carex lasiocarpa, and Phragmites australis) were selected to analyze the changes of soil organic carbon (SOC) and total nitrogen (TN) contents and various indices of microbial characteristics including soil sucrose, catalase, cellulase, microbial biomass carbon/nitrogen (MBC/MBN), microbial respiration (MBR), microbial quotient (qMB), and metabolic quotient (qCO2), as well as the correlations among them. The results showed that SOC and TN contents de- creased with increasing the soil depth, and varied significantly (P < 0.01) in the different wetland types. Soil enzyme activities (except catalase), MBC, MBN and MBR also decreased significantly with increasing the soil depth in the wetlands with the greatest activities being detected in surface soil (0-10 cm). In soil layer of 0-30 cm, several parameters (including SOC, TN, soil enzyme activities, MBC, MBN, MBR, qMB and qCO2) were higher in the wetlands dominated by C. angustifolia + S. brachypoda and C. angustifolia, compared with those with C. lasiocarpa and P. australis as dominant plant species. Statistical analyses revealed significant correlations (P < 0.01) between major microbial indicators (except qCO2) with SOC and TN contents in the soils. It demonstrated that the microbial characteristics were the major indicators, and played an important role in the changes of SOC and TN in wetland soils.

  12. Effects of soil characteristics on grape juice nutrient concentrations and other grape quality parameters in Shiraz

    Science.gov (United States)

    Concepción Ramos, Maria; Romero, Maria Paz

    2017-04-01

    H; soil characteristics, sugar content.

  13. THE STUDY OF DEFORMATION CHARACTERISTICS OF SOIL MATERIALS WITH THE USAGE OF WASTES

    Directory of Open Access Journals (Sweden)

    L. V. Trykoz

    2017-04-01

    Full Text Available Purpose. More often the qualified building materials are replaced by the industrial wastes for environmental improvement. This refers to both metallurgical slags and biological solids of water treatment plants. In order to understand the possibilities of their usage it needs studying deformation properties of composite soil materials with industrial wastes addition. Methodology. The soil of real buildings and structures foundation is in the complicated conditions and the stress-strained state. While studying this state the total deformation modulus Е0 is used as the deformation characteristic. This one is determined according to the results of sample soil testing in the compression instrument (odometer. This instrument prevents the possibility of lateral expansion of sample soil under the vertical load. Findings. As a result of the testing the compression curves are plotted as the dependence of the porosity coefficient on pressure. These data allow determining the compressibility coefficient and the strain modulus. It is found that a biological solids addition increases the compressibility coefficient four times compared to the clay. The two types of samples are compared. The first type contains 50% of biological solids. The second type contains 50% of biological solids and 50% of slag. The comparison shows that the second type is compressed twelve times less. An addition into the clay of biological solids increases the strain modulus from 7.8 to 20.3 MPa. The slag increases the strain modulus to 52.7 MPa. Originality. While making the composition based clay materials the functional groups of biological solids interact with hydroxyl groups which are placed on the surface of clay particles and form a spatial structure. Besides an addition of biological solids contributes to peptization, soil aggregates destroy themselves, and form contacts between separate particles. It causes the decrease of soil compressibility due to the total porosity

  14. Kinetic characteristic of phenanthrene sorption in aged soil amended with biochar

    Science.gov (United States)

    Kim, Chanyang; Kim, Yong-Seong; Hyun, Seunghun

    2015-04-01

    Biochar has been recently highlighted as an amendment that affects yield of the crops by increasing pH, cation exchange capacity and water retention, and reduces the lability of contaminants by increasing sorption capacity in the soil system. Biochar's physico-chemical properties, high CEC, surfaces containing abundant micropores and macropores, and various types of functional groups, play important roles in enhancing sorption capacity of contaminants. Aging through a natural weathering process might change physico-chemical properties of biochar amended in soils, which can affect the sorption behavior of contaminants. Thus, in this study, the sorption characteristics of phenanthrene (PHE) on biochar-amended soils were studied with various types of chars depending on aging time. To do this, 1) soil was amended with sludge waste char (SWC), wood char (WC), and municipal waste char (MWC) during 0, 6, and 12 month. Chars were applied to soil at 1% and 2.5% (w/w) ratio. 2) Several batch kinetic and equilibrium studies were conducted. One-compartment first order and two-compartment first order model apportioning the fraction of fast and slow sorbing were selected for kinetic models. Where, qt is PHE concentration in biochar-amended soils at each time t, qeis PHE concentration in biochar-amended soils at equilibrium. ff is fastly sorbing fraction and (1-ff) is slowly sorbing fraction. k is sorption rate constant from one-compartment first order model, k1 and k2 are sorption rate constant from two-compartment first order model, t is time (hr). The equilibrium sorption data were fitted with Fruendlich and Langmuir equation. 3) Change in physico-chemical properties of biochar-amended soils was investigated with aging time. Batch equilibrium sorption results suggested that sorbed amount of PHE on WC was greater than SWC and MWC. The more char contents added to soil, the greater sorption capacity of PHE. Sorption equilibrium was reached after 4 hours and equilibrium pH ranged

  15. Predicted tyre-soil interface area and vertical stress distribution based on loading characteristics

    DEFF Research Database (Denmark)

    Schjønning, Per; Stettler, M.; Keller, Thomas

    2015-01-01

    The upper boundary condition for all models simulating stress patterns throughout the soil profile is the stress distribution at the tyre–soil interface. The so-called FRIDA model (Schjønning et al., 2008. Biosyst. Eng. 99, 119–133) treats the contact area as a superellipse and has been shown...... to accurately describe a range of observed vertical stress distributions. Previous research has indicated that such distributions may be predicted from tyre and loading characteristics. The objective of this study was to establish a stepwise calculation procedure enabling accurate predictions from readily...... the tyre’s ability to distribute the stress in the driving direction and in the transversal direction, respectively, increased with increases in the relevant contact area dimension (length or width). The α-parameter was further affected by FW, while Kr and L added to model performance for the β...

  16. [Moisture and nutrient characteristics of deep layer soil in apple orchards on the Luochuan highland of Shaanxi, Northwest China].

    Science.gov (United States)

    Cao, Yu; Jumahan, Kasimu; Fan, Peng; Zhang, Li-Na; Li, Jun

    2013-02-01

    Taking the 11-, 15-, 20-, and 43 years old apple orchards on the Luochuan highland of Shaanxi, Northwest China as test objects, this paper measured the moisture content in 0-1500 cm soil layer and the organic matter and total and available nitrogen, phosphorous, and potassium contents in 0-300 cm soil layer, with the soil moisture and nutrient regimes as well as their variation characteristics with apple tree age and soil depth analyzed. The moisture content in 0-1500 cm soil layer in 11-, 15-, 20-, and 43 years old apple orchards was averagely 18.6%, 13.7%, 17.0%, 11.5%, and 13.1%, respectively, and decreased with apple tree age. Soil desiccation did not occurr in the orchards with supplementary irrigation, but a slight or medium soil desiccation occurred in the rainfed orchards. Nevertheless, the moisture content in 0-300 cm soil layer in the rainfed orchards was still higher than that in wheat field. The contents of organic matter and total and available nitrogen in 0-300 cm soil layer in the five apple orchards were less than 10 g.kg-1, 0.75 g. kg-1, and 50 mg.kg-1, respectively, all at shortage level, whilst the content of available phosphorous in 0-300 cm soil layer was 3.30-6.42 mg.kg-1, being moderate in upper soil layer and scarce in deep soil layer. The content of available potassium in 0-300 cm soil layer was 78.09-98.31 mg.kg-1, presenting abundant. The contents of nutrients were all higher in 0-100 cm soil layer than in 100-300 cm soil layer. The soil organic matter and total and available nitrogen contents and the soil nutrient index (SNI) all presented a trend of decrease after an initial increase with the increasing apple tree age. The contents of the test nutrients except total potassium in 0-100 cm soil layer all decreased rapidly with soil depth, while those in deeper soil layers kept relatively stable. There existed significant correlations between the contents of soil organic matter, total nitrogen, available nitrogen, total phosphorous

  17. BETWEEN THE RIGHT AND THE COMMON. HOW GROUPS REACT TO SOCIALLY UNDESIRABLE BEHAVIOUR

    Directory of Open Access Journals (Sweden)

    Komendant-Brodowska Agata

    2017-06-01

    Full Text Available The aim of the paper is to analyse the relationship between group characteristics and the scope of reaction of the group to socially undesirable behaviour. Sometimes small groups or communities fail to react to undesirable or violent behaviour and their apathy can have devastating consequences. Such a situation can occur among co-workers witnessing workplace mobbing, or neighbours who do not react to a suspicion of domestic violence. Reasons for their inaction are diverse and can include fear, doubts concerning the necessity of such a reaction, and also conformity. In the paper I examine a seemingly favourable situation: I assume that reaction is costless and all the members of the group would like to react (internalised norm, but they also want to conform. In order to analyse the factors that can influence the scope of group reaction, a structurally embedded sequential coordination game was played for different initial conditions. Computer simulations were conducted for networks of a specific type (Erd¨os-R´enyi random graph. The main aim of the analysis was to identify non-structural and structural features of the group that can impede or even block the intervention of the group. There is a positive relationship between the scope of group reaction and the strength of the internalized norm, whereas the level of conformity affects the chances of group intervention in a negative way. Heterogeneity of the group is an important factor - the scope of reaction is higher when members of the group have different levels of norm internalisation and conformity. There is a non-linear relationship between network density and the scope of reaction. Both low and high density can make it harder for people to act.

  18. MICROBIAL CHARACTERISTICS OF SOILS UNDER AN INTEGRATED CROP-LIVESTOCK SYSTEM

    Directory of Open Access Journals (Sweden)

    Andréa Scaramal da Silva

    2015-02-01

    Full Text Available Integrated crop-livestock systems (ICLs are a viable strategy for the recovery and maintenance of soil characteristics. In the present study, an ICL experiment was conducted by the Instituto Agronômico do Paraná in the municipality of Xambre, Parana (PR, Brazil, to evaluate the effects of various grazing intensities. The objective of the present study was to quantify the levels of microbial biomass carbon (MBC and soil enzymatic activity in an ICL of soybean (summer and Brachiaria ruziziensis (winter, with B. ruziziensis subjected to various grazing intensities. Treatments consisted of varying pasture heights and grazing intensities (GI: 10, 20, 30, and 40 cm (GI-10, GI-20, GI-30, and GI-40, respectively and a no grazing (NG control. The microbial characteristics analysed were MBC, microbial respiration (MR, metabolic quotient (qCO2, the activities of acid phosphatase, β-glucosidase, arylsuphatase, and cellulase, and fluorescein diacetate (FDA hydrolysis. Following the second grazing cycle, the GI-20 treatment (20-cm - moderate grazing intensity contained the highest MBC concentrations and lowest qCO2 concentrations. Following the second soybean cycle, the treatment with the highest grazing intensity (GI-10 contained the lowest MBC concentration. Soil MBC concentrations in the pasture were favoured by the introduction of animals to the system. High grazing intensity (10-cm pasture height during the pasture cycle may cause a decrease in soil MBC and have a negative effect on the microbial biomass during the succeeding crop. Of all the enzymes analyzed, only arylsuphatase and cellulase activities were altered by ICL management, with differences between the moderate grazing intensity (GI-20 and no grazing (NG treatments.

  19. Variations in fuel characteristics of corn (Zea mays) stovers: General spatial patterns and relationships to soil properties

    Energy Technology Data Exchange (ETDEWEB)

    Xiong, Shaojun [Unit of Biomass Technology and Chemistry, Swedish University of Agricultural Sciences, SE-901 83 Umeaa (Sweden); College of Life Science, Beijing Normal University, Beijing (China); Zhang, Yufen [College of Life Science, Beijing Normal University, Beijing (China); Zhuo, Yue [Biomass Engineering Centre, China Agricultural University, Beijing (China); Lestander, Torbjoern; Geladi, Paul [Unit of Biomass Technology and Chemistry, Swedish University of Agricultural Sciences, SE-901 83 Umeaa (Sweden)

    2010-06-15

    The geographic variations in corn stover fuel and soil characteristics from 22 sites in the Kerchin region (43.8-45.0 N, 122.7-125.1 E), north-east China, were examined in both 2006 and 2007. The correlations between fuel characteristics and soil parameters were analysed using principal component analysis (PCA) and partial least squares regression (PLS). The main emphasis was on the feasibility of using corn stovers as feedstock in direct combustion for heat and power generation. The examined corn stovers from Kerchin generally have similar characteristics to energy grasses grown in Europe and may be used as biofuels. However, large variations, up to several orders of magnitude, in the fuel characteristics existed among the samples. With PCA, the studied soils showed a clear distinction between soluble and less soluble elements, with a trend for higher insoluble element (such as Si) concentrations in south-western soils and a higher pH in the more northern soils. The component for fuel characteristics showed a distinct trend with latitude that can be explained by the above-mentioned soil component pattern. PLS regression models suggested some important relationships that may be used to predict corn stover fuel characteristics using soil and environment properties; for example, latitude, soil pH and Si are the most important predictors for Ca content in corn stovers, but not for K that is best predicted by soil K. Although limited by numbers of samples and sites, this study indicated that this approach can be used to predict biofuel quality. (author)

  20. Importance of organic amendment characteristics on bioremediation of PAH-contaminated soil.

    Science.gov (United States)

    Lukić, B; Huguenot, D; Panico, A; Fabbricino, M; van Hullebusch, E D; Esposito, G

    2016-08-01

    This study investigates the importance of the organic matter characteristics of several organic amendments (i.e., buffalo manure, food and kitchen waste, fruit and vegetables waste, and activated sewage sludge) and their influence in the bioremediation of a polycyclic aromatic hydrocarbons (PAH)-contaminated soil. The removal of low molecular weights (LMW) and high molecular weights (HMW) PAHs was monitored in four bioremediation reactors and used as an indicator of the role of organic amendments in contaminant removal. The total initial concentration of LMW PAHs was 234 mg kg(-1) soil (dry weight), while the amount for HMW PAHs was 422 mg kg(-1) soil (dry weight). Monitoring of operational parameters and chemical analysis was performed during 20 weeks. The concentrations of LMW PAH residues in soil were significantly lower in reactors that displayed a mesophilic phase, i.e., 11 and 15 %, compared to reactors that displayed a thermophilic phase, i.e., 29 and 31 %. Residual HMW PAHs were up to five times higher compared to residual LMW PAHs, depending on the reactor. This demonstrated that the amount of added organic matter and macronutrients such as nitrogen and phosphorus, the biochemical organic compound classes (mostly soluble fraction and proteins), and the operational temperature are important factors affecting the overall efficiency of bioremediation. On that basis, this study shows that characterization of biochemical families could contribute to a better understanding of the effects of organic amendments and clarify their different efficiency during a bioremediation process of PAH-contaminated soil.

  1. Engineering Geological Characteristics of the Residual Soil, Lower Quaternary Sediments in Kertajati Region, Majalengka, West Java

    Directory of Open Access Journals (Sweden)

    Untung Sudarsono

    2014-06-01

    Full Text Available DOI: 10.17014/ijog.v6i3.125Only few engineering geological researches on residual soil have been conducted in Indonesia, whereas many infrastructure projects take place on undulating area and mountainous area which are composed of residual soils. The paper discusses residual soil characteristics of the Lower Quaternary sediment (Qos in Kertajati area, Majalengka. The methodology of the research consists of engineering geological mapping, in situ test using 2.5 ton penetrometer, sampling and laboratory test for index properties, Atterberg limits, grain size analysis, and strength tests. Field test analysis data show that the thickness of residual soil resting on the basement rock in the study area varies from 2.40 - 14.20 m. Upwards, it comprises sands, silts, and clays, respectively. Laboratory analysis data indicate that the residual soil is dominated by fine-grained fraction, composed of high plastic clay (CH. Relationship among engineering geological parameters was analysed using linear regression and tested using statistic method t-test to find real correlation among variables within 95 - 90% significance level.. Based on the test, there are real positive correlation with 19 degree of freedom and 5% and 10% level of significance are found in between plasticity indexes (IP and liquid limits (LL, between plasticity indexes (IP and clay contents (C, between specific gravities (G and clay contents (C. The real negative correlation with nine degree of freedom and 5% and 10% level of significance occurs in between cohesion (c dengan friction angle (φ. Corelation between degree of saturation (G and clay contents (C with 19 degree of freedom is found in 10% level of significance.

  2. Trace elements assessment in agricultural and desert soils of Aswan area, south Egypt: Geochemical characteristics and environmental impacts

    Science.gov (United States)

    Darwish, Mohamed Abdallah Gad; Pöllmann, Hebert

    2015-12-01

    Determination of chemical elements, Al, Cd, Co, Cr, Cu, Fe, Li, Mn, Mo, Ni, P, Pb, Sc, Sr, Ti, Y, and Zn have been performed in agricultural and desert soils and alfalfa (Medicago sativa) at Aswan area. Consequently, the pollution indices, univariate and multivariate statistical methods have been applied, in order to assess the geochemical characteristics of these elements and their impact on soil environmental quality and plant, and to reach for their potential input sources. The investigation revealed that the mean and range values of all element concentrations in agricultural soil are higher than those in desert soil. Furthermore, the agricultural soil displayed various degrees of enrichment and pollution of Cd, Zn, Mo, Co, P, Ti, Pb. The geochemical pattern of integrated pollution indices gave a clear image of extreme and strong pollution in the agricultural soil stations, their poor quality with high risk to human health and considered as a tocsin for an alert. In contrast, the desert soil is the good environmental quality and safe for plant, animal and human health. Alfalfa is tolerant plant and considered as a biomarker for P and Mo in polluted agricultural soil. Four geochemical associations of analyzing elements in agricultural soil and three ones in desert soil have been generated, and their enhancements were essentially caused by various anthropogenic activities and geogenic sources. The investigation also revealed that the broad extended desert soil is fruitful and promising as cultivable lands for agricultural processes in the futures.

  3. Determination of the Characteristic Values and Variation Ratio for Sensitive Soils

    Science.gov (United States)

    Milutinovici, Emilia; Mihailescu, Daniel

    2017-12-01

    In 2008, Romania adopted Eurocode 7, part II, regarding the geotechnical investigations – called SR EN1997-2/2008. However a previous standard already existed in Romania, by using the mathematical statistics in determination of the calculation values, the requirements of Eurocode can be taken into consideration. The setting of characteristics and calculations values of the geotechnical parameters was finally issued in Romania at the end of 2010 at standard NP122-2010 – “Norm regarding determination of the characteristic and calculation values of the geotechnical parameters”. This standard allows using of data already known from analysed area and setting the calculation values of geotechnical parameters. However, this possibility exist, it is not performed easy in Romania, considering that there isn’t any centralized system of information coming from the geotechnical studies performed for various objectives of private or national interests. Every company performing geotechnical studies tries to organize its own data base, but unfortunately none of them use existing centralized data. When determining the values of calculation, an important role is played by the variation ratio of the characteristic values of a geotechnical parameter. There are recommendations in the mentioned Norm, that could be taken into account, regarding the limits of the variation ratio, but these values are mentioned for Quaternary age soils only, normally consolidated, with a content of organic material < 5%. All of the difficult soils are excluded from the Norm even if they exist and affect the construction foundations on more than a half of the Romania’s surface. A type of difficult soil, extremely widespread on the Romania’s territory, is the contractile soil (with high swelling and contractions, very sensitive to the seasonal moisture variations). This type of material covers and influences the construction foundations in one over third of Romania’s territory. This work is

  4. To Evaluate the Effect of Soil Physical and Chemical Characteristics on the Growth Characteristics of Saffron (Crocus sativus L. Corms in Tornbat-e Heydariyeh Area

    Directory of Open Access Journals (Sweden)

    Fariba Zarghani

    2016-07-01

    Full Text Available Introduction Saffron is one of the most economically important plants across Iran and all over the world. The most important cultivated areas of saffron are in Khorasan-e Razavi and Southern Khorasan provinces (Jihad Keshavarzi Khorasan Razavi, 2013. The corm is the reservoir of photosynthetic materials and plays an important role in the saffron life cycle. Corm size and physicochemical characteristics of soil determine the growth and yield of saffron (Aytekin et al., 2008. It has been advised to use corms with diameter more than 2.5 cm (Kafi et al., 2002. Despite the importance of this plant, few studies have been conducted on the effects of soil characteristics on the growth of the plant in natural field conditions. Therefore, the objective which we will try to achieve is: to evaluate the effect of soil physical and chemical characteristics of the growth of saffron corm and determine the most important effect characteristics. Materials and methods In September 2012, 30 samples of 3 to 5 years old saffron corms were taken from the fields with similar management in Torbat Heydariyeh. The surrounding soil corms (depth of 0 to 30 cm were sampled, too. Dry weight of corms was measured in the laboratory. Air dried soil samples were passed through a 2 mm sieve and used for physical-chemical analyses. Soil texture was determined by using pipet method. Total nitrogen, available phosphorous, available potassium, soil organic carbon and calcium carbonate equivalent were measured in bulk soil samples. Calcium, magnesium, sodium, EC and pH were measured in the saturated soil paste. Fe, Cu and Zn were extracted by DTPA and measured by atomic adsorption spectroscopy. Correlation, regression and neural network technique were used to analyze the data and to identify the most important soil characteristics on the corms characteristics. Results and discussion Diameter and dry weight of corms with mean values of 34.04 mm and 3.72 g, ranged from 22.8 to 51.7 mm

  5. Heterogeneity of soil surface ammonium concentration and other characteristics, related to plant specific variability in a Mediterranean-type ecosystem

    International Nuclear Information System (INIS)

    Cruz, Cristina; Bio, Ana M.F.; Jullioti, Aldo; Tavares, Alice; Dias, Teresa; Martins-Loucao, Maria Amelia

    2008-01-01

    Heterogeneity and dynamics of eight soil surface characteristics essential for plants-ammonium and nitrate concentrations, water content, temperature, pH, organic matter, nitrification and ammonification rates-were studied in a Mediterranean-type ecosystem on four occasions over a year. Soil properties varied seasonally and were influenced by plant species. Nitrate and ammonium were present in the soil at similar concentrations throughout the year. The positive correlation between them at the time of greatest plant development indicates that ammonium is a readily available nitrogen source in Mediterranean-type ecosystems. The results presented here suggest that plant cover significantly affects soil surface characteristics. - In Mediterranean-type ecosystems ammonium is present in the soil throughout the year and its concentration is dependent on plant cover

  6. Physicochemical Characteristics and Ecological Risk Assessment of Heavy Metals Contaminated Soils in Copper Mining of Nulasai, Xinjiang, China

    Directory of Open Access Journals (Sweden)

    Dina·Tursenjan

    2017-12-01

    Full Text Available Taking the mining areas, tailings and surrounding farmland soil of the Nulasai copper mine in Xinjiang as the research object, the characteristics of soil physical and characteristics of heavy metal contents in this area were studied, and their ecological and environmental risks were preliminarily evaluated. The results showed that due to the long-term impact of mining wastewater, soil pH in the Nulasai mining area was relatively low. Soil conductivity and salt content were higher than those in the surrounding farmland, while soil organic matter, available nitrogen, available potassium and available phosphorus were lower than those in the surrounding farmland. The contents of heavy metals Cr, Cd, Pb, Cu, Ni and Zn in the mining area, tailing area and farmland soil were all lower than those in Xinjiang except for Cu. Overall, the heavy metal content of the soil manifested the area > tailing area > farmland. Single factor(Pi, Nemerow comprehensive pollution index(I and potential ecological risk index(RI indicated that the ecological risk of heavy metals in the soil around the mining area was manifested tailings > mining area > farmland. The potential ecological risk index of heavy metals in 0~30 cm topsoil was higher than that in 30~70 cm deep soil, but the overall ecological risk was lower in different land use types.

  7. Effect of Physicochemical Characteristics of Soil on Population Density of Arbuscular Mycorrhizal Fungi in the Roots of Grapevine in Urmia

    Directory of Open Access Journals (Sweden)

    A. Mahdavi Bileh Savar

    2015-01-01

    Full Text Available Relationship of is one of the most useful interactions in terrestrial ecosystems that its positive effects on growth, physiology and ecology of different plants has been documented. This study investigated the relationship between important physicochemical characteristics of soils such as pH, electrical conductivity (EC, soil texture, organic carbon percentage, soil potassium percentage and the amount of accessible phosphorus with population of mycorrhizal fungi. After dividing the study region into four areas, 43 samples of soil were collected. The results of statistical analysis on physico-chemical characteristics of soil and their relation with population density of spores of arbuscular mycorrhizal fungi showed that there was a negative correlation between electrical conductivity (EC, pH, clay percent, and percent of soil available phosphorus, potassium percent, and percentage of organic carbon with the mean number of fungi. There were positive correlations between silt and sand percentages and mean number of spores present in the soil. Based on the coefficien of determination and based on study conditions, the best model for the rhizosphere was found tobe the one in wich available phosphorus percent of soil was the independent variable, and mean population of fungi as the dependant variable. The correlation between available phosphorus percent in soil samples with average fungi population density negative (P<0/05, but there was not a meaningful correlation between other traits and population density of fungi

  8. Behavior of Copper Oxide Nanoparticles in Soil Pore Waters as Influenced by Soil Characteristics, Bacteria, and Wheat Roots

    OpenAIRE

    Hortin, Joshua

    2017-01-01

    The goal of this project was to study the behavior of copper oxide nanoparticles in soil environments. Copper oxide nanoparticles have antimicrobial properties and may also be used in agricultural settings to provide a source of copper for plant health, but accidental or misapplication of these nanoparticles to soil may be damaging to the plant and its associated bacteria. Dissolved soil organic matter that is present in soil pore waters dissolved nanoparticles, but did not dissolve the ex...

  9. Geophysical mapping of soil static characteristics and monitoring of soil dynamic states: an example on agricultural land.

    Science.gov (United States)

    Cassiani, G.; Ursino, N.; Deiana, R.; Vignoli, G.; Boaga, J.; Rossi, M.; Perri, M. T.; Blaschek, M.; Duttmann, R.; Meyer, S.; Ludwig, R.; Soddu, A.; Dietrich, P.; Werban, U.

    2012-04-01

    In this contribution we the results of nearly three years of non invasive monitoring of the soil conditions in an experimental farm in a region of semi-arid climate in Southern Sardinia. The main of the study is to understand the effects of soil types and soil-vegetation interactions on soil water balance. The adopted technique is a combination of time-lapse electromagnetic induction (EMI) monitoring over wide areas and localized irrigation tests monitored by electrical resistivity tomography (ERT) and TDR soil moisture measurements, with the general aim of achieving quantitative field-scale estimates of moisture content of the first meter of topsoil. Mapping of natural gamma-ray emission, texture analysis and laboratory calibration of an electrical constitutive relationship on soil samples complete the dataset. Unlike remote sensing techniques, non invasive geophysics penetrates the soil subsurface and can effectively image moisture content in the soil active layer. We observed that the growth of vegetation, with the associated below ground allocation of biomass, has a significant impact on the soil moisture dynamics. In particular vegetation extracts a large amount of water from the soil in the hot season, but it also reduces evaporation by shadowing the soil surface. In addition, vegetation enhances the soil wetting process as the root system facilitates water infiltration, thus creating a positive feedback system.

  10. The effect of soil physiochemical characteristics and field age on agronomic traits of saffron (Crocus sativus L.

    Directory of Open Access Journals (Sweden)

    E. Azizi

    2016-05-01

    Full Text Available In order to Investigation some soil characteristics and filed age effects on flower and corm yield of saffron, an experiment was conducted as factorial based on complete randomized design with five replications in two regions of Neyshabur during growing season 2009-2010. Treatments were included different filed ages (2, 4 and 6 years and two geographical regions (Eshagh abad and Soltan abad. Different characteristics such as fresh and dry weight of corm, corm number, number of corm sprout and flower and stigma yield of saffron were determined. Soil physical and chemical characteristics such as soil texture, pH and EC were measured. Results showed that effect of filed age on all characteristics was statistically significant. Flower and stigma yield were affected by region and filed age and region interaction significantly. Positive significant regression was shown between field age and parameters such as fresh and dry weight of corm, number of corm sprout and corm number. With increasing field age to 4 years, saffron yield increased and then decreased. Results showed that changes in stigma and flower yield was significantly related to physical and chemical soil criteria (soil texture, EC, pH characteristics. Significant negative correlations were observed between clay percentage of soil with corm number, corm dry weight, flower and stigma in.

  11. Seasonal phosphatase activity in three characteristic soils of the English uplands polluted by long-term atmospheric nitrogen deposition

    International Nuclear Information System (INIS)

    Turner, B.L.; Baxter, Robert; Whitton, B.A.

    2002-01-01

    High soil phosphatase activities confirm strong biological phosphorus limitations due to nitrogen deposition. - Phosphomonoesterase activities were determined monthly during a seasonal cycle in three characteristic soil types of the English uplands that have been subject to long-term atmospheric nitrogen deposition. Activities (μmol para-nitrophenol g -1 soil dry wt. h -1 ) ranged between 83.9 and 307 in a blanket peat (total carbon 318 mg g -1 , pH 3.9), 45.2-86.4 in an acid organic grassland soil (total carbon 354 mg g -1 , pH 3.7) and 10.4-21.1 in a calcareous grassland soil (total carbon 140 mg g -1 , pH 7.3). These are amongst the highest reported soil phosphomonoesterase activities and confirm the strong biological phosphorus limitation in this environment

  12. Distribution characteristics of available trace elements in soil from a reclaimed land in a mining area of north Shaanxi, China

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    Li Zhanbin

    2013-06-01

    Full Text Available Through field and laboratory tests we studied the temporal and spatial variation in the soil content of four available trace elements :copper(Cu, iron(Fe, manganese(Mn and zinc (Zn, to analyze their distribution characteristics in reclaimed mining land under different reclamation conditions. The available trace elements content varied considerably with different land reclamation patterns. Extended reclamation time was helpful for the recovery of the available trace element content in the soil, and after more than eight years of soil reclamation, the content of available trace elements was closer to or greater than that in soil under natural conditions. Various treatment measures significantly influenced the content and distribution of available trace elements in the soil, and reasonable artificial treatments, including covering the soil and growing shrubs and herbaceous plants, increased the content of available trace elements.

  13. Soil wettability in forested catchments in South Africa; as measured by different methods and as affected by vegetation cover and soil characteristics

    Science.gov (United States)

    Scott, D. F.

    2000-05-01

    Earlier studies in South Africa had shown that water repellency in the soils of timber plantations was associated with a greater risk of overland flow and soil erosion on mountain slopes. This paper reports on a follow-up study to determine how prevalent water repellent soils are in the forestry areas of South Africa, and to what extent this phenomenon is associated with specific vegetation types. Soils from a representative series of forestry sites around South Africa were sampled from beneath each genus or plantation type and the range of local vegetation types. These soils were dried at low oven temperatures and then subjected to a series of tests of soil wettability, namely, water drop penetration time, infiltration rate, critical surface tension and apparent advancing contact angle as determined by the equilibrium capillary rise test. Water repellency is common in dried soils from timber plantations. The dominant variation in repellency is explained by the different vegetation types: soils beneath eucalypts are most repellent, followed by those beneath wattle (Acacia species), indigenous forest and pine. Soils beneath grassland and fynbos scrub were least likely to show repellency, perhaps because regular fires remove plant litter and thus the potential for hydrophobic substances to develop. Soil characteristics explained very little of the variation in repellency. Organic carbon content was weakly correlated with higher repellency, but organic carbon content and soil texture added little explanation to models that first accounted for variation in vegetation type and point of origin. These results are broadly the same regardless of which method of measuring repellency was used. However, the critical surface tension test was far superior to the others in terms of information gained, speed, efficiency and statistical utility of the resultant scores.

  14. Continuous measurement of soil-water characteristic curves at low suction levels

    Science.gov (United States)

    Ray, Richard; Bene, Katalin

    2017-04-01

    The soil-water characteristic curve (SWCC) is an important piece of information for understanding unsaturated soil behavior. With few exceptions, most of the SWCCs are developed as discrete points and are typically generated under drying path. This study presents results from automated tests that typically draw suction values to about 1 bar. Tempe cells are used with the axis translation method to generate the curves. Soils tested include fine sand, silty, and clayey sands. While a typical test starts in a saturated state and generates a drying curve, the test can be reversed any number of times to produce hysteresis behavior. Another advantage to the method is time efficiency since a curve with thousands of data points are produced in less than a week. However, careful consideration has to be made with regard to extraction rate, especially as the specimen becomes dryer. Several data sets are presented illustrating good and problematic behavior as well as hysteresis. Some suggestions are given concerning the selection of extraction rates or adjusting curves to account for extraction rate effects.

  15. Teaches’ Reactions towards Undesirable Behaviors of Administrators: Whistle-blowing or Keeping Silent?

    Directory of Open Access Journals (Sweden)

    Asiye TOKER GÖKÇE

    2015-11-01

    Full Text Available This research aims to define teachers’ attitudes towards undesired behaviours at school. Therefore, in which possible undesired administrative behaviours teachers would blow a whistle was examined. Second, whether the teachers would prefer whistle-blowing or and the kind of blowing was questioned. Lastly, the reason of keeping silence was examined. This research was designed as qualitative model. The research group was 20 teachers that work at a secondary school in Darica district of Kocaeli. The results revealed that it was put forward that all teachers would react in the case of various undesired behaviours. However it was determined that teachers would mostly react in the case of serious undesired behaviours. Teachers mostly stated that they would prefer to whistle-blow internally, formally and by identifying themselves. Findings of the research are thought to contribute to the literature in terms of revealing teachers’ attitudes towards possible undesired behaviours at school.

  16. Exploring the Role of the Spatial Characteristics of Visible and Near-Infrared Reflectance in Predicting Soil Organic Carbon Density

    Directory of Open Access Journals (Sweden)

    Long Guo

    2017-10-01

    Full Text Available Soil organic carbon stock plays a key role in the global carbon cycle and the precision agriculture. Visible and near-infrared reflectance spectroscopy (VNIRS can directly reflect the internal physical construction and chemical substances of soil. The partial least squares regression (PLSR is a classical and highly commonly used model in constructing soil spectral models and predicting soil properties. Nevertheless, using PLSR alone may not consider soil as characterized by strong spatial heterogeneity and dependence. However, considering the spatial characteristics of soil can offer valuable spatial information to guarantee the prediction accuracy of soil spectral models. Thus, this study aims to construct a rapid and accurate soil spectral model in predicting soil organic carbon density (SOCD with the aid of the spatial autocorrelation of soil spectral reflectance. A total of 231 topsoil samples (0–30 cm were collected from the Jianghan Plain, Wuhan, China. The spectral reflectance (350–2500 nm was used as auxiliary variable. A geographically-weighted regression (GWR model was used to evaluate the potential improvement of SOCD prediction when the spatial information of the spectral features was considered. Results showed that: (1 The principal components extracted from PLSR have a strong relationship with the regression coefficients at the average sampling distance (300 m based on the Moran’s I values. (2 The eigenvectors of the principal components exhibited strong relationships with the absorption spectral features, and the regression coefficients of GWR varied with the geographical locations. (3 GWR displayed a higher accuracy than that of PLSR in predicting the SOCD by VNIRS. This study aimed to help people realize the importance of the spatial characteristics of soil properties and their spectra. This work also introduced guidelines for the application of GWR in predicting soil properties by VNIRS.

  17. Transfer characteristics of cadmium and lead from soil to the edible parts of six vegetable species in southeastern China

    International Nuclear Information System (INIS)

    Wang Guo; Su Miaoyu; Chen Yanhui; Lin Fenfang; Luo Dan; Gao Shufang

    2006-01-01

    The transfer characteristics of Cd and Pb from soils to the edible parts of six vegetable species were calculated from plant and corresponding surface soil samples collected from the fields in Fujian Province, southeastern China. The soil-to-plant transfer factors (TF) calculated from both total and DTPA-extractable Cd and Pb in the soils decreased with increasing total or DTPA-extractable Cd and Pb, indicating that the TF values of Cd and Pb depend on the soil metal content. For most plants studied, there was a significant relation between the TF values and the corresponding soil metal concentrations (total or DTPA-extractable) that was best described by an exponential equation (y = ax b ). We recommend that the representative TF value for a given crop-metal system should be estimated from the regression models between the transfer factors and the corresponding soil metal concentrations and at a given soil metal concentration. - Soil-to-plant transfer factors of Cd and Pb decreased with increasing soil contents of Cd and Pb

  18. Regime Shifts and Ecosystem Service Generation in Swedish Coastal Soft Bottom Habitats: When Resilience is Undesirable

    Directory of Open Access Journals (Sweden)

    Max Troell

    2005-06-01

    Full Text Available Ecosystems can undergo regime shifts where they suddenly change from one state into another.  This can have important implications for formulation of management strategies, if system characteristics develop that are undesirable from a human perspective, and that have a high resistance to restoration efforts. This paper identifies some of the ecological and economic consequences of increased abundance of filamentous algae on shallow soft bottoms along the Swedish west coast. It is suggested that a successive increase in the sediment nutrient pool has undermined the resilience of these shallow systems. After the regime shift has occurred, self-generation properties evolve keeping the system locked in a high-density algae state. The structural and functional characteristics of the new system state differ significantly from the original one, resulting in less valuable ecosystem goods and services generated for society. In Sweden, loss of value results from the reduced capacity for mitigating further coastal eutrophication, reduced habitat quality for commercial fishery species, and the loss of aesthetic and recreational values.

  19. Soils

    Science.gov (United States)

    Emily Moghaddas; Ken Hubbert

    2014-01-01

    When managing for resilient forests, each soil’s inherent capacity to resist and recover from changes in soil function should be evaluated relative to the anticipated extent and duration of soil disturbance. Application of several key principles will help ensure healthy, resilient soils: (1) minimize physical disturbance using guidelines tailored to specific soil types...

  20. Characteristic of Soil Nutrients Loss in Beiyunhe Reservoir Under the Simulated Rainfall

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    LIU Cao

    2016-05-01

    Full Text Available Field nutrient loss from soil became the major factor of the water pollution control in countryside in China. Beiyunhe reservoir is located in semiarid zone, where field nutrient loss distributed in summer. To assess the flied nutrient loss in Beiyunhe reservoir, we conducted experiments to study the characteristic of soil nutrients loss by analysis of the content of runoff water, soil nutrients and runoff water sediment under simulated rainfall. The results showed that the runoff happened in the rainstorm. In runoff water, the content of TN was 4.7~11.3 mg·L-1, ammonia nitrogen and nitrate nitrogen accounted for 44.51% of TN; the content of P was 0.66~1.35 mg·L-1, water soluble phosphorus accounted for 54.08% of TP. And the main loss of nutrients was in the surface soil, the loss of TN, NH4+-N, NO3--N, TP and DP were 29.79%, 52.09%, 10.21%, 16.48% and 5.27%, respectively. However, the most of field nutrient loss were in runoff sediment, the content of TN and TP were 0.66~1.27 mg·g-1 and 14.73~20 mg·g-1 in sediment, and TN and TP account for 82.28% and 99.89% of total loss of nutrient. After the rainstorm, the macro-aggregates were reduced 8.8%, and the micro-aggregates increased 9.5%.

  1. Soil-geomorphic significance of land surface characteristics in an arid mountain range, Mojave Desert, USA

    Science.gov (United States)

    Hirmas, D.R.; Graham, R.C.; Kendrick, K.J.

    2011-01-01

    Mountains comprise an extensive and visually prominent portion of the landscape in the Mojave Desert, California. Landform surface properties influence the role these mountains have in geomorphic processes such as dust flux and surface hydrology across the region. The primary goal of this study was to describe and quantify land surface properties of arid-mountain landforms as a step toward unraveling the role these properties have in soil-geomorphic processes. As part of a larger soil-geomorphic study, four major landform types were identified within the southern Fry Mountains in the southwestern Mojave Desert on the basis of topography and landscape position: mountaintop, mountainflank, mountainflat (intra-range low-relief surface), and mountainbase. A suite of rock, vegetation, and morphometric land surface characteristic variables was measured at each of 65 locations across the study area, which included an associated piedmont and playa. Our findings show that despite the variation within types, landforms have distinct land surface properties that likely control soil-geomorphic processes. We hypothesize that surface expression influences a feedback process at this site where water transports sediment to low lying areas on the landscape and wind carries dust and soluble salts to the mountains where they are washed between rocks, incorporated into the soil, and retained as relatively long-term storage. Recent land-based video and satellite photographs of the dust cloud emanating from the Sierra Cucapá Mountains in response to the 7.2-magnitude earthquake near Mexicali, Mexico, support the hypothesis that these landforms are massive repositories of dust.

  2. PHOSPHOGYPSUM AND VINASSE APPLICATION: SOIL CHEMICAL PROPERTIES AND ALFALFA PRODUCTIVITY AND NUTRITIONAL CHARACTERISTICS

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    RONALDO DO NASCIMENTO

    2017-01-01

    Full Text Available The objective of this work was to evaluate the effects of the application of phosphogypsum and vinasse on soil chemical properties and productivity and nutritional characteristics of alfalfa (Medicago sativa. The experiment was conducted in a randomized block design, using a 3×5 factorial arrangement, with three vinasse rates (0, 150 and 300 m3 ha-1 and five phosphogypsum rates (0, 3, 6, 9 and 12 Mg ha-1. The alfalfa chemical composition and shoot dry matter (SDW and soil chemical properties (in the layers 0.0-0.2 and 0.21-0.4 m were evaluated. The vinasse rates increased the soil potassium contents, while the phosphogypsum rates promoted linear increases in soil calcium and sulfur contents. The base saturation was increased and the magnesium content showed a quadratic response on the layer 0.21-0.4 m with the increase in phosphogypsum rates. The calcium, magnesium and phosphorus contents in the alfalfa leaves were lower with vinasse application. The phosphogypsum rates promoted linear increases in alfalfa SDW. Vinasse rated 150 m3 ha-1 was been enough to SDW increase. Calcium and magnesium contents in the leaves fitted a quadratic model, with maximum calcium content in the phosphogypsum rate of 9.5 Mg ha-1 and the minimum magnesium content in the phosphogypsum rate of 8.7 Mg ha-1. The leaf sulfur contents in all vinasse rates and leaf potassium contents in the highest vinasse rate showed maximum accumulation at near 9 Mg ha-1 of phosphogypsum.

  3. Study on Hyperspectral Characteristics and Estimation Model of Soil Mercury Content

    Science.gov (United States)

    Liu, Jinbao; Dong, Zhenyu; Sun, Zenghui; Ma, Hongchao; Shi, Lei

    2017-12-01

    In this study, the mercury content of 44 soil samples in Guan Zhong area of Shaanxi Province was used as the data source, and the reflectance spectrum of soil was obtained by ASD Field Spec HR (350-2500 nm) Comparing the reflection characteristics of different contents and the effect of different pre-treatment methods on the establishment of soil heavy metal spectral inversion model. The first order differential, second order differential and reflectance logarithmic transformations were carried out after the pre-treatment of NOR, MSC and SNV, and the sensitive bands of reflectance and mercury content in different mathematical transformations were selected. A hyperspectral estimation model is established by regression method. The results of chemical analysis show that there is a serious Hg pollution in the study area. The results show that: (1) the reflectivity decreases with the increase of mercury content, and the sensitive regions of mercury are located at 392 ~ 455nm, 923nm ~ 1040nm and 1806nm ~ 1969nm. (2) The combination of NOR, MSC and SNV transformations combined with differential transformations can improve the information of heavy metal elements in the soil, and the combination of high correlation band can improve the stability and prediction ability of the model. (3) The partial least squares regression model based on the logarithm of the original reflectance is better and the precision is higher, Rc2 = 0.9912, RMSEC = 0.665; Rv2 = 0.9506, RMSEP = 1.93, which can achieve the mercury content in this region Quick forecast.

  4. Impact of soil characteristics and land use on pipe erosion in a temperate humid climate: Field studies in Belgium

    Science.gov (United States)

    Verachtert, E.; Van Den Eeckhaut, M.; Martínez-Murillo, J. F.; Nadal-Romero, E.; Poesen, J.; Devoldere, S.; Wijnants, N.; Deckers, J.

    2013-06-01

    This study investigates the role of soil characteristics and land use in the development of soil pipes in the loess belt of Belgium. First, we tested the hypothesis that discontinuities in the soil profile enhance lateral flow and piping by impeding vertical infiltration. We focus on discontinuities in soil characteristics that can vary with soil depth, including texture, saturated hydraulic conductivity, penetration resistance, and bulk density. These characteristics as well as soil biological activity were studied in detail on 12 representative soil profiles for different land use types. Twelve sites were selected in the Flemish Ardennes (Belgium): four pastures with collapsed pipes (CP), four pastures without CP, two sites under arable land without CP and two sites under forest without CP. Secondly, this study aimed at evaluating the interaction of groundwater table positions (through soil augerings) and CP in a larger area, with a focus on pastures. Pasture is the land use where almost all CP in the study area are observed. Therefore, the position of the groundwater table was compared for 15 pastures with CP and 14 pastures without CP, having comparable topographical characteristics in terms of slope gradient and contributing area. Finally, the effect of land use history on the occurrence of pipe collapse was evaluated for a database of 84 parcels with CP and 84 parcels without CP, currently under pasture. As to the first hypothesis, no clear discontinuities for abiotic soil characteristics in soil profiles were observed at the depth where pipes occur, but pastures with CP had significantly more earthworm channels and mole burrows at larger depths (> 120 cm: mean of > 200 earthworm channels per m2) than pastures without CP, arable land or forest (> 120 cm depth, a few or no earthworm channels left). The land use history appeared to be similar for the pastures with and without CP. Combining all results from soil profiles and soil augering indicates that intense

  5. NATURE AND CHARACTERISTICS OF SOIL AFFECTING THE GROWTH OF AREN PLANT (Arenga pinnata (Wurmb. Merr

    Directory of Open Access Journals (Sweden)

    Rosi Widarawati

    2017-09-01

    Full Text Available Aren plant (Arenga pinnata can produce industrial raw materials. Almost all parts of palm trees can be utilized, namely young and old leaves, young endosperms, stems, stem bunches of flowers, roots, and fibers. Sugar leaves used for the roof of the house or hut. Young endosperms are used for fleas as a mixture of food or drink. Stem aren tree can be taken flour for the manufacture of palm flour. The main problem is the unclear growth of aren trees caused by soil characteristics in various places. The objectives of the study were to: 1 understanding the effect of land characteristic on the growth of aren trees; 2 look for various growth characters of aren plants at different altitudes. The study was conducted by survey and observation. Location was selected by purposive sampling, i.e. areas with altitude ( 700 m ASL. The results showed differences results. Aren plant cultivation techniques that include the way of nursery, maintenance and post harvest management not implemented in Kulonprogo region, especially Ngargosari village, Pagerharjo, and Nglinggo. There is influence of altitude factors of place, soil type, morphology, physiology, and biochemistry to growth and aren products.

  6. Role of soil characteristics on analysis of water flow in shallow land

    International Nuclear Information System (INIS)

    Tohaya, Takayuki; Wakabayashi, Noriaki; Wadachi, Yoshiki.

    1987-09-01

    Analysis of water flow on posutulated model grounds has been carried out by using 2-dimensional finite element analytical model, to clarify the effects of soil characteristics (hydroulic conductivities in saturated and unsaturated zones, moisture content - water head relationship, porosity, etc.) of a shallow land layer on variations in water tables and water flow rates. Results thus obtained indicate that hydroulic conductivities in saturated and unsaturated zones play an important role in governing the development of a water table, especially the hydroulic conductivity of the top layer and of the layers near the water table give significant effect on the water table development. It was found through multiple regression analyses of the variation of the water table that among soil characteristics following parameters give pronounced effect on the development of the water table in the order; the relationship between moisture content of the unsaturated zone and pressure head, the distance between the water table and ground surface, and the saturated hydroulic conductivity of the layer immediately above the water table. (author)

  7. Characteristics of biochars from crop residues: potential for carbon sequestration and soil amendment.

    Science.gov (United States)

    Windeatt, Jayne H; Ross, Andrew B; Williams, Paul T; Forster, Piers M; Nahil, Mohamad A; Singh, Surjit

    2014-12-15

    Biochar has potential to sequester carbon in soils and simultaneously improve soil quality and plant growth. More understanding of biochar variation is needed to optimise these potential benefits. Slow pyrolysis at 600 °C was undertaken to determine how yields and characteristics of biochars differ when produced from eight different agricultural residues. Biochar properties such as carbon content, surface area, pH, ultimate and proximate analysis, nutrient and metal content and the R50 recalcitrance index were determined. Significant variations seen in biochar characteristics were attributed to feedstock variation since pyrolysis conditions were constant. Biochar yields varied from 28% to 39%. Average carbon content was 51%. Ash content of both feedstocks and biochars were correlated with biochar carbon content. Macronutrients were concentrated during pyrolysis, but biochar macronutrient content was low in comparison to biochars produced from more nutrient rich feedstocks. Most biochars were slightly alkaline, ranging from pH 6.1 to pH 11.6. pH was correlated with biochar K content. Aromaticity was increased with pyrolysis, shown by a reduction in biochar H/C and O/C ratios relative to feedstock values. The R50 recalcitrance index showed biochars to be either class 2 or class 3. Biochar carbon sequestration potential was 21.3%-32.5%. The R50 recalcitrance index is influenced by the presence of alkali metals in the biochar which may lead to an under-estimation of biochar stability. The residues assessed here, at current global availability, could produce 373 Mt of biochar. This quantity of biochar has the potential to sequester 0.55 Pg CO2 yr(-1) in soils over long time periods. Copyright © 2014 Elsevier Ltd. All rights reserved.

  8. Effect of Grazing Intensity on Some Soil Chemical Characteristics in Gardaneh Zanburi Rangeland of Arsanjan

    Directory of Open Access Journals (Sweden)

    zeinab khademolhosseini

    2016-02-01

    Full Text Available Introduction:Changes caused by grazing on range ecosystem are generally assessed based on the soil conditions and vegetation. Livestock as one of the major elements in range land ecosystems has different effects on different parts of this ecosystem. One of these impacts is excessive livestock grazing capacity which can have different effects on soils and plants in various intensities. Materials and Methods:Gardaneh ZanbooriRangelandis located in Arsanjan in Fars province. This isanareaof mountains, hillsandplains with the maximum height of 2280 meters and minimum height of 1640 meters above sea level. Related areas were separated under three different management methods of enclosure, moderate grazing and heavy grazing. These three areas are considered as symbolic areas of grazing intensity including the reference area where no grazing intensity was observed, the key area where medium to heavy grazing was applied and critical area where heavy grazing was used. These areas were similar in all characteristics such as topography, soil type and rainfall and differed only in their grazing intensity factor. Then, soil samples were collected. Random systematic soil sampling was conducted at two horizons of 0 -15 and 15 -30 cm. Therefore, five profiles in each area (enclosure, moderate grazing and heavy grazing, a total of 15 soil profiles, were excavated and two samples were taken in each profile (one sample from each horizon. Finally, the thirty soil samples were transported to the laboratory. Samples were dried in the air laboratory and passed a two millimeter sieve after smashing. Factors such as N, P, K, OM, EC and PH were measured in each sample In the laboratory, the percentage of P was determined by the Olsen method while the percentage of K was determined using the flamephotometry method. Moreover, N was measured using the Kjeldhal method. C was measured by the Walkley and Black method. The percentage of OM was found by carbon multiplying

  9. Drought-induced root plasticity of two upland NERICA varieties under conditions with contrasting soil depth characteristics

    Directory of Open Access Journals (Sweden)

    Daniel Makori Menge

    2016-07-01

    Full Text Available To identify differences in root plasticity patterns of two upland New Rice for Africa (NERICA varieties, NERICA 1 and 4, in response to drought under conditions with contrasting soil profile characteristics, soil moisture gradients were imposed using a sloping bed system with depths ranging 30–65 cm and a line-source sprinkler system with a uniformly shallow soil layer of 20 cm depth. Varietal differences in shoot and root growths were identified only under moderate drought conditions, 11–18% v/v soil moisture content. Further, under moderate drought soil conditions where roots could penetrate into the deep soil layer, deep root development was greater in NERICA 4 than in NERICA 1, which contributed to maintaining dry matter production. However, under soil conditions with underground impediment to deep root development, higher shoot dry weight was noted for NERICA 1 than for NERICA 4 at 11–18% v/v soil moisture content, which was attributed to increased lateral root development in the shallow soil layer in NERICA 1. Enhanced lateral root development in the 0–20-cm soil layer was identified in NERICA 1 even under soil conditions without an impediment to deep root development; however, this did not contribute to maintaining dry matter production in upland rice. Thus, we show different root developmental traits associated with drought avoidance in the two NERICA varieties, and that desirable root traits for upland rice cultivation vary depending on the target soil environment, such as the distribution of soil moisture and root penetration resistance.

  10. Effects of Rainfall Characteristics on the Stability of Tropical Residual Soil Slope

    Directory of Open Access Journals (Sweden)

    Rahardjo Harianto

    2016-01-01

    Full Text Available Global climate change has a significant impact on rainfall characteristics, sea water level and groundwater table. Changes in rainfall characteristics may affect stability of slopes and have severe impacts on sustainable urban living. Information on the intensity, frequency and duration of rainfall is often required by geotechnical engineers for performing slope stability analyses. Many seepage analyses are commonly performed using the most extreme rainfall possible which is uneconomical in designing a slope repair or slope failure preventive measure. In this study, the historical rainfall data were analyzed and investigated to understand the characteristics of rainfall in Singapore. The frequency distribution method was used to estimate future rainfall characteristics in Singapore. New intensity-duration-frequency (IDF curves for rainfall in Singapore were developed for six different durations (10, 20, 30 min and 1, 2 and 24 h and six frequencies (2, 5, 10, 25, 50 and 100 years. The new IDF curves were used in the seepage and slope stability analyses to determine the variation of factor of safety of residual soil slopes under different rainfall intensities in Singapore.

  11. The occurrence, sources and spatial characteristics of soil salt and assessment of soil salinization risk in Yanqi basin, northwest China.

    Science.gov (United States)

    Zhaoyong, Zhang; Abuduwaili, Jilili; Yimit, Hamid

    2014-01-01

    In order to evaluate the soil salinization risk of the oases in arid land of northwest China, we chose a typical oasis-the Yanqi basin as the research area. Then, we collected soil samples from the area and made comprehensive assessment for soil salinization risk in this area. The result showed that: (1) In all soil samples, high variation was found for the amount of Ca2+ and K+, while the other soil salt properties had moderate levels of variation. (2) The land use types and the soil parent material had a significant influence on the amount of salt ions within the soil. (3) Principle component (PC) analysis determined that all the salt ion values, potential of hydrogen (pHs) and ECs fell into four PCs. Among them, PC1 (C1-, Na+, SO4(2-), EC, and pH) and PC2 (Ca2+, K+, Mg2+and total amount of salts) are considered to be mainly influenced by artificial sources, while PC3 and PC4 (CO3(-) and HCO3(2-)) are mainly influenced by natural sources. (4) From a geo-statistical point of view, it was ascertained that the pH and soil salt ions, such as Ca2+, Mg2+ and HCO3(-), had a strong spatial dependency. Meanwhile, Na+ and Cl- had only a weak spatial dependency in the soil. (5) Soil salinization indicators suggested that the entire area had a low risk of soil salinization, where the risk was mainly due to anthropogenic activities and climate variation. This study can be considered an early warning of soil salinization and alkalization in the Yanqi basin. It can also provide a reference for environmental protection policies and rational utilization of land resources in the arid region of Xinjiang, northwest China, as well as for other oases of arid regions in the world.

  12. The occurrence, sources and spatial characteristics of soil salt and assessment of soil salinization risk in Yanqi basin, northwest China.

    Directory of Open Access Journals (Sweden)

    Zhang Zhaoyong

    Full Text Available In order to evaluate the soil salinization risk of the oases in arid land of northwest China, we chose a typical oasis-the Yanqi basin as the research area. Then, we collected soil samples from the area and made comprehensive assessment for soil salinization risk in this area. The result showed that: (1 In all soil samples, high variation was found for the amount of Ca2+ and K+, while the other soil salt properties had moderate levels of variation. (2 The land use types and the soil parent material had a significant influence on the amount of salt ions within the soil. (3 Principle component (PC analysis determined that all the salt ion values, potential of hydrogen (pHs and ECs fell into four PCs. Among them, PC1 (C1-, Na+, SO4(2-, EC, and pH and PC2 (Ca2+, K+, Mg2+and total amount of salts are considered to be mainly influenced by artificial sources, while PC3 and PC4 (CO3(- and HCO3(2- are mainly influenced by natural sources. (4 From a geo-statistical point of view, it was ascertained that the pH and soil salt ions, such as Ca2+, Mg2+ and HCO3(-, had a strong spatial dependency. Meanwhile, Na+ and Cl- had only a weak spatial dependency in the soil. (5 Soil salinization indicators suggested that the entire area had a low risk of soil salinization, where the risk was mainly due to anthropogenic activities and climate variation. This study can be considered an early warning of soil salinization and alkalization in the Yanqi basin. It can also provide a reference for environmental protection policies and rational utilization of land resources in the arid region of Xinjiang, northwest China, as well as for other oases of arid regions in the world.

  13. [Variation characteristic in soil respiration of apple orchard and its biotic and abiotic influencing factors].

    Science.gov (United States)

    Wang, Rui; Guo, Sheng-Li; Liu, Qing-Fang; Zhang, Yan-Jun; Jiang, Ji-Shao; Guo, Hui-Min; Li, Ru-Jian

    2014-05-01

    To evaluate the orchard variability of soil respiration and the response of soil respiration to its influencing factors is helpful for a deep understanding about the effects of converting cropland to apple orchard. A field experiment was conducted in the Changwu State Key Agro-Ecological Station. Soil respiration, soil temperature, soil moisture and roots biomasses were periodically measured in a mature apple orchard during 2011 and 2012. Soil respiration decreased as the distance from the trunk increased. The cumulative soil respiration in the 0.5 m-distance from the trunk was 20% and 31% higher than that in the 2 m-distance from the trunk, respectively in 2011 and 2012. The temperature sensitivity of soil respiration (Q10) was relatively lower in the 2 m-distance than that in the 0. 5 m-distance in both years. Soil temperature and soil moisture were slightly higher in the 2 m-distance, but there was no significant difference between the 2 m-distance and the 0. 5 m-distance. Soil respiration and soil temperature showed a significant exponential relationship, but there was no positive correlation between soil moisture and soil respiration. Soil temperature changes can explain seasonal variation of soil respiration well, but it could not explain its spatial variability. Root density was an important factor for the spatial variability of soil respiration and Q15. Variation of soil respiration coefficient was 23% -31%. Therefore, the distance from the trunk should be considered when estimating orchards soil respiration.

  14. The Use of Adsorbent Materials of Improving the Characteristics of Polluted Soils, Part 1 Phytoremediation of Soils Polluted with Oil Products, Cultivated with Technical Plants

    Directory of Open Access Journals (Sweden)

    Smaranda Masu

    2015-10-01

    Full Text Available In this study are presented in pot experimental variants regarding alternatives to improve the characteristics of soils polluted with 74.12 ± 3.50 g·kg-1 D.M. total petroleum hydrocarbon (TPH in order to apply the phytoremediation process using technical plants from the common flax (Linum usitatissimum. The harmful effects of TPH polluted soils to plants was reduced by using fly ash from thermal plant as temporary adsorbent of non-polar pollutants, petroleum products. The increase of water retention capacity of the soil was achieved by treatments with indigenous volcanic tuff. The lack of nutrients, based on N and P in soils contaminated with TPH rich in C compounds are completed using sewage sludge anaerobically stabilized. The use of appropriate amounts of fly ash and fertilizer agents in the presence of volcanic tuff caused the formation of strong networks of roots and rich harvests of plants, stems and seeds from the treated soil. The TPH reduction efficiency of TPH polluted soils treated with fly ash (TPH soil: fly ash ratio 12:1 wt. / wt. and anaerobically stabilized sewage sludge respectively indigenous volcanic tuff during one vegetative cycle of crops was in the range of 56.2 - 63.25 %.

  15. Exo-polysaccharides (eps) producing biofilm bacteria in improving physico-chemical characteristics of the salt- affected soils

    International Nuclear Information System (INIS)

    Ashraf, M.; Hussain, F.; Hasnain, S.

    2005-01-01

    A greenhouse study was conducted to compare the effect of inoculation of an EPS-producing bacterial strain (isolated from roots of wheat plants grown in a salt-affected soil) on the extent of soil aggregation around roots of wheat plants grown for 15 or 30 days in saline and non-saline soils. The results showed that the association of the inoculated EPS-producing bacterium was higher with roots of the inoculated wheat plants grown in saline than non-saline soil. This higher association of the EPS-producing bacterium with roots of wheat plants could be attributed to the effect of soluble salts content of the salt-affected soil. An increase in soil aggregation around roots of the inoculated wheat plants grown in saline soil over control could be beneficial in terms of improving physico-chemical characteristics of the salt-affected soils. Thus it could be concluded that inoculation of EPS- producing bacteria could help ameliorate fertility and productivity of the salt-affected. An enhanced productivity of the salt-affected soils would lead to improved environmental conditions of surroundings of the salt-affected lands. (author)

  16. Effect of modifying land cover and long-term agricultural practices on the soil characteristics in native forest-land.

    Science.gov (United States)

    Gol, Ceyhun; Dengiz, Orhan

    2008-09-01

    Natural forestland soils in the high land mountain ecosystems on the eastern Black sea region of Turkey are being seriously degraded and destructed due to intensive agricultural practices. In this study we examined four soil profiles selected from four sites in each of three adjacent land use types which are native forest, pasture and cultivated fields with corn and hazelnut to compare the soil physical, chemical and morphological properties modified after natural forestland transformation into cultivated land. Disturbed and undisturbed soil samples were collected from four sites. The effects of agricultural practices on soil properties taken from each three adjacent land use types were most clearly detected in the past 50 years with the land use change. Land use change and subsequent tillage practices resulted in significant decreases in organic matter, total porosity, total nitrogen and reduced soil aggregates stability. However, contents of available P were improved by application of phosphorous fertilizers in cultivated system. There was also a significant change in bulk density among cultivated, pasture and natural forest soils. Depending upon the increase in bulk density and disruption of pores by cultivation, total porosity decreased accordingly. The data show that long term continuous cultivation of the natural forest soils resulted in changes in physical and chemical characteristics of soils.

  17. [Pollution characteristics and sources of polycyclic aromatic hydrocarbons in riparian soils along urban rivers of Wenzhou city].

    Science.gov (United States)

    Zhou, Jie-Cheng; Bi, Chun-Juan; Chen, Zhen-Lou; Wang, Lu; Xu, Shi-Yuan; Pan, Qi

    2012-12-01

    Twenty one riparian soil samples along Jiushanwai River and Shanxia River of Wenzhou city were collected in August 2010 to investigate the pollution characteristics of polycyclic aromatic hydrocarbons (PAHs). The samples were extracted by an accelerated solvent extractor (ASE), purified by a purification column and determined by GC-MS. Results showed that the total concentrations of PAHs in the riparian soils ranged from 60.7 ng x g(-1) to 3 871.3 ng x g(-1), and the concentrations of sigma PAHs in soils along the Shanxia River were significantly lower than the levels along Jiushanwai River. The dominant compounds were 2 to 3 rings in the riparian soils along both rivers, which in average accounted for 62.47% - 72.51% in sigma PAHs. Compared with the PAHs concentrations in soils of other areas in the world, the riparian soils of the studied rivers were moderately polluted by PAHs, but the concentrations of BaP in three soil samples were much higher than the soil standard value of the former Soviet Union, which should be paid more attention. Based on the ratios of Ant/(Ant + Phe) and Fla/(Fla + Pyr) and principal component analysis results, PAHs in riparian soils of the studied rivers were mainly derived from both the petroleum and combustion.

  18. Effects of organic and conventional management of sugar cane crop on soil physicochemical characteristics and phosphomonoesterase activity.

    Science.gov (United States)

    Purcena, Luiza L A; Di Medeiros, Maria Carolina B; Leandro, Wilson M; Fernandes, Kátia F

    2014-02-19

    Soil enzymes play an important role in agriculture and particularly in nutrient cycling. They are also involved in the degradation, transformation, and mineralization of organic matter and availability of nutrients in soil. It is believed that organic agriculture causes fewer losses to soil quality and is less aggressive to the environment than conventional management. In this study, the effects of conventional (CM) and organic management (OM) on phosphomonoesterases, an important enzyme for soil fertility, were evaluated and compared to those results from native Cerrado (Brazilian Savanna) soil (NS), because they are the most common phosphatases in soils. The results showed that there were both acid (AcP) and alkaline (AkP) phosphatases in all soils tested and that AcP activity was higher than that of AkP. In contrast to AkP, AcP had its activity affected by land use. In the cultivated areas there was a reduction of almost 50% of AcP activity respect to native unexploited soils and there was no significant difference between organic and CM, demonstrating that independent of the management chosen, there was an impact of land use on AcP activity. Principal component analysis indicated that characteristics related to pH such as alkali saturation (V%), aluminum saturation (M%), Al(3+), soil total acidity (H+Al), and Ca(2+) are the main factors that permit distinguishing NS from OM and CM.

  19. Quantifying the Interactions Between Soil Thermal Characteristics, Soil Physical Properties, Hydro-geomorphological Conditions and Vegetation Distribution in an Arctic Watershed

    Science.gov (United States)

    Dafflon, B.; Leger, E.; Robert, Y.; Ulrich, C.; Peterson, J. E.; Soom, F.; Biraud, S.; Tran, A. P.; Hubbard, S. S.

    2017-12-01

    Improving understanding of Arctic ecosystem functioning and parameterization of process-rich hydro-biogeochemical models require advances in quantifying ecosystem properties, from the bedrock to the top of the canopy. In Arctic regions having significant subsurface heterogeneity, understanding the link between soil physical properties (incl. fraction of soil constituents, bedrock depth, permafrost characteristics), thermal behavior, hydrological conditions and landscape properties is particularly challenging yet is critical for predicting the storage and flux of carbon in a changing climate. This study takes place in Seward Peninsula Watersheds near Nome AK and Council AK, which are characterized by an elevation gradient, shallow bedrock, and discontinuous permafrost. To characterize permafrost distribution where the top of permafrost cannot be easily identified with a tile probe (due to rocky soil and/or large thaw layer thickness), we developed a novel technique using vertically resolved thermistor probes to directly sense the temperature regime at multiple depths and locations. These measurements complement electrical imaging, seismic refraction and point-scale data for identification of the various thermal behavior and soil characteristics. Also, we evaluate linkages between the soil physical-thermal properties and the surface properties (hydrological conditions, geomorphic characteristics and vegetation distribution) using UAV-based aerial imaging. Data integration and analysis is supported by numerical approaches that simulate hydrological and thermal processes. Overall, this study enables the identification of watershed structure and the links between various subsurface and landscape properties in representative Arctic watersheds. Results show very distinct trends in vertically resolved soil temperature profiles and strong lateral variations over tens of meters that are linked to zones with various hydrological conditions, soil properties and vegetation

  20. Soil characteristics of two locations in Swisher and Deaf Smith Couties, Palo Duro Basin, Texas

    International Nuclear Information System (INIS)

    1984-12-01

    The soil is the resource on which the important economic activity of both the Swisher County and Deaf Smith County locations is based. Soils are discussed in terms of where they occur on the natural landscape. Major soil associations and the primary soil series included in them are described for both locations. Agricultural, engineering and reclamation interpretations are drawn from three published soil surveys. Field inspection of location soils was not performed

  1. Adsorption-desorption characteristics of Ni, Zn and Pb in soils of a landfill environment in Metro Manila, Philippines

    International Nuclear Information System (INIS)

    Castañeda, Soledad S.; Cuarto, Christina D.; David, Carlos Primo C.

    2015-01-01

    This study investigated the sorption-desorption characteristics of Ni, Zn, and Pb on two soil types in the environment of a municipal waste disposal facility. Batch experiments were carried out in ambient temperature and in unadjusted and close to soil field pH conditions. The kinetics of of adsorption fitted a pseudo second-order model. Rate constants were calculated and an empirical model for predicting adsorption of metal ions at a given time was derived from these constants. The equilibrium sorption capacities for the heavy metals in the clay and sandy loam soils were estimated using the Linear, Freundlich, and Langmuir isotherm models. The sorption process of Ni, Pb, and Zn in both soils generally fitted well with the Freundlich isotherm model at moderate to high initial concentration range of the metals. The Langmuir isotherm was applicable to the adsorption of Ni and Zn only. The adsorption capacity of the clay soil for the metals followed the order Zn > Pb > Ni. In the sandy loam soil, the adsorption capacity for the metals under the same conditions followed the order Pb > Zn > Ni. The adsorption capacities for the metals were in order of 1mg/g in both the landfill clay soil and the Lukutan River sandy loam soil, with slightly higher values for the clay soil. Desorption was minimal, less than 1% in the clay soil and about 2% in the sandy loam soil. Sorption reversibility tests showed that the retention of the metals in both soils follows the order Ni> Pb> Zn. (author)

  2. Influence of Characteristic-Soil-Property-Estimation Approach on the Response of Monopiles for Offshore Wind Turbines

    DEFF Research Database (Denmark)

    Andersen, Lars Vabbersgaard; Sørensen, John Dalsgaard; Kim, Sun-Bin

    2015-01-01

    , and pile–soil interaction is modelled by the Winkler approach with nonlinear p–y curves for the soil resistance. The 5MW NREL reference wind turbine is employed for load estimation, utilizing the aeroelastic code FAST. The study includes comparison of monopile capacities based on a single CPT as well......Different approaches to estimation of the characteristic undrained shear strength of soil are discussed, based on 12 cone penetration tests (CPTs) carried out within a soil volume representative of an offshore monopile foundation. The paper is focused on the statistical treatment of the data...... as multiple CPTs. Comparisons are made between results obtained from a single CPT and those from all the CPTs at the site. The influence of assuming few or many layers in the deterministic soil model is assessed, and different assumptions regarding the statistical distribution of the data are compared...

  3. [Distribution characteristics of soil organic carbon and its composition in Suaeda salsa wetland in the Yellow River delta].

    Science.gov (United States)

    Dong, Hong-Fang; Yu, Jun-Bao; Guan, Bo

    2013-01-01

    Applying the method of physical fractionation, distribution characteristics of soil organic carbon and its composition in Suaeda salsa wetland in the Yellow River delta were studied. The results showed that the heavy fraction organic carbon was the dominant component of soil organic carbon in the studied region. There was a significantly positive relationship between the content of heavy fraction organic carbon, particulate organic carbon and total soil organic carbon. The ranges of soil light fraction organic carbon ratio and content were 0.008% - 0.15% and 0.10-0.40 g x kg(-1), respectively, and the range of particulate organic carbon ratio was 8.83% - 30.58%, indicating that the non-protection component of soil organic carbon was low and the carbon pool was relatively stable in Suaeda salsa wetland of the Yellow River delta.

  4. Spectroscopic characteristics of soil organic matter as a tool to assess soil physical quality in Mediterranean ecosystems

    Science.gov (United States)

    Recio Vázquez, Lorena; Almendros, Gonzalo; Knicker, Heike; López-Martín, María; Carral, Pilar; Álvarez, Ana

    2014-05-01

    In Mediterranean areas, the loss of soil physical quality is of particular concern due to the vulnerability of these ecosystems in relation to unfavourable climatic conditions, which usually lead to soil degradation processes and severe decline of its functionality. As a result, increasing scientific attention is being paid on the exploration of soil properties which could be readily used as quality indicators, including organic matter which, in fact, represents a key factor in the maintenance of soil physical status. In this line, the present research tackles the assessment of the quality of several soils from central Spain with the purpose of identifying the physical properties most closely correlated with the organic matter, considering not only the quantity but also the quality of the different C-forms. The studied attributes consist of a series of physical properties determined in field and laboratory conditions-total porosity, aggregate stability, available water capacity, air provision, water infiltration rate and soil hydric saturation-.The bulk organic matter was characterised by solid-state 13C NMR spectroscopy and the major organic fractions (lipids, free particulate organic matter, fulvic acids, humic acids and humin) were quantified using standard procedures. The humic acids were also analysed by visible and infrared spectroscopies. The use of multidimensional scaling to classify physical properties in conjunction with molecular descriptors of soil organic matter, suggested significant correlations between the two set of variables, which were confirmed with simple and canonical regression models. The results pointed to two well-defined groups of physical attributes in the studied soils: (i) those associated with organic matter of predominantly aromatic character (water infiltration descriptors), and (ii) soil physical variables related to organic matter with marked aliphatic character, high preservation of the lignin signature and comparatively low

  5. Long-term grazing effects on vegetation characteristics and soil properties in a semiarid grassland, northern China.

    Science.gov (United States)

    Zhang, Jing; Zuo, Xiaoan; Zhou, Xin; Lv, Peng; Lian, Jie; Yue, Xiyuan

    2017-05-01

    Understanding the responses of vegetation characteristics and soil properties to grazing disturbance is useful for grassland ecosystem restoration and management in semiarid areas. Here, we examined the effects of long-term grazing on vegetation characteristics, soil properties, and their relationships across four grassland types (meadow, Stipa steppe, scattered tree grassland, and sandy grassland) in the Horqin grassland, northern China. Our results showed that grazing greatly decreased vegetation cover, aboveground plant biomass, and root biomass in all four grassland types. Plant cover and aboveground biomass of perennials were decreased by grazing in all four grasslands, whereas grazing increased the cover and biomass of shrubs in Stipa steppe and of annuals in scattered tree grassland. Grazing decreased soil carbon and nitrogen content in Stipa steppe and scattered tree grassland, whereas soil bulk density showed the opposite trend. Long-term grazing significantly decreased soil pH and electrical conductivity (EC) in annual-dominated sandy grassland. Soil moisture in fenced and grazed grasslands decreased in the following order of meadow, Stipa steppe, scattered tree grassland, and sandy grassland. Correlation analyses showed that aboveground plant biomass was significantly positively associated with the soil carbon and nitrogen content in grazed and fenced grasslands. Species richness was significantly positively correlated with soil bulk density, moisture, EC, and pH in fenced grasslands, but no relationship was detected in grazed grasslands. These results suggest that the soil carbon and nitrogen content significantly maintains ecosystem function in both fenced and grazed grasslands. However, grazing may eliminate the association of species richness with soil properties in semiarid grasslands.

  6. Soil pore characteristics assessed from X-ray micro-CT derived images and correlations to soil friability

    DEFF Research Database (Denmark)

    Munkholm, Lars Juhl; Heck, R; Deen, B

    2012-01-01

    X-ray computed tomography (CT) scanning technology has, in recent decades, been shown to be a very powerful technique to visualize and quantify soil structure. The objective of this project was to quantify soilporecharacteristics, on undisturbed field moist soil, using a high resolution X-rayCT s...

  7. Geological Engineering Characteristics of the Residual Soil: Implementation for Soil Bearing Capacity at Gayungan, Surabaya, East Java

    Science.gov (United States)

    Rukmana, Y. Y.; Ridwan, M.

    2018-01-01

    This paper presents the results of soil investigation on the residual soil at Gayungan Surabaya. The methodology of the research consists of Drilling + Standard Penetration Test (ASTM D1586-99), sampling and laboratory test for index properties & mechanical of soil, then analyzed for Soil Bearing Capacity (Meyerhoff, 1976). Field test analysis data showed that Bore Hole.01(BH.01) and Bore Hole.03 (BH.03) were dominated by Sand / Sandy clay layer with Standart Penetration Test (SPT) values: 6-68, whereas in BH.02 was dominated by Clayey sand layer with Standard Penetration Test (SPT) values: 32-68. Based on Soil classification according to Unified Soil Classification System (USCS), the soil type at the research area consisted of ML (Silt with Low plasticity), CL ( Clay with low plasticity), MH (Silt with High plasticity), and SP (Sand with Poor gradation). Based on the borlog data and soil bearing capacity analysis of the research area is recommended: for The Deep foundation to reaches at least 16 meters depth with Qa = 1160.40-2032.80 kN / m2, and Shallow foundation reaches at least 1-2 meters deep with Qa = 718.25 kN / M2.

  8. The presence of undesirable mould species on the surface of dry sausages

    Directory of Open Access Journals (Sweden)

    Vesković-Moračanin Slavica M.

    2008-01-01

    Full Text Available Transition from manufacture to the industrial way of meat production and processing, as well as contemporary concept of food quality and safety, have led to the application of starter cultures. Their application leads towards the streamlining of the production process in the desired direction, quality improvement and its harmonization, and thereby to its standardization. Application of moulds in the meat industry is based on positive effects of their proteolytic and lipolytic egzoenzymes which, as a consequence, leads to the creation of characteristic sensory properties ('flavor' of fermented products. Penicillium nalgiovense is a typical representative of moulds used in the production of fermented sausages-salamis from our region. Samples of 'zimska salama' (dry sausage, produced with Penicillium nalgiovense, were evaluated as hygienically unacceptable. Their sensory properties changed due to contamination of this mould during the ripening process. Micological analysis discovered the presence of Penicillium aurantiogriseum, which is a frequent mould contaminant in the meat industry. At the same time, thin layer chromatography revealed no possibility of metabolic activity of this mould in the creation of mycotoxins. However, the presence of this mould on the surface of 'zimska salama' is considered as undesirable due to formation of 'off flavor' in products. Such product is considered as hygienically unacceptable and cannot be used for the human consumption.

  9. Characteristics of soil under variations in clay, water saturation, and water flow rates, and the implications upon soil remediation

    International Nuclear Information System (INIS)

    Aikman, M.; Mirotchnik, K.; Kantzas, A.

    1997-01-01

    A potential remediation method for hydrocarbon contaminated soils was discussed. The new method was based on the use of proven and economic petroleum reservoir engineering methods for soil remediation. The methods that were applied included water and gas displacement methods together with horizontal boreholes as the flow inlet and outlets. This system could be used in the case of spills that seep beneath a plant or other immovable infrastructure which requires in-situ treatment schemes to decontaminate the soil. A study was conducted to characterize native soils and water samples from industrial plants in central Alberta and Sarnia, Ontario and to determine the variables that impact upon the flow conditions of synthetic test materials. The methods used to characterize the soils included X-Ray computed tomographic analysis, grain size and density measurements, and X-Ray diffraction. Clay content, initial water saturation, and water and gas flow rate were the variables that impacted on the flow conditions

  10. Short-Term Effect of Feedstock and Pyrolysis Temperature on Biochar Characteristics, Soil and Crop Response in Temperate Soils

    DEFF Research Database (Denmark)

    Nelissen, Victoria; Ruysschaert, Greet; Müller-Stöver, Dorette Sophie

    2014-01-01

    At present, there is limited understanding of how biochar application to soil could be beneficial to crop growth in temperate regions and which biochar types are most suitable. Biochar’s (two feedstocks: willow, pine; three pyrolysis temperatures: 450 °C, 550 °C, 650 °C) effect on nitrogen (N......) availability, N use efficiency and crop yield was studied in northwestern European soils using a combined approach of process-based and agronomic experiments. Biochar labile carbon (C) fractions were determined and a phytotoxicity test, sorption experiment, N incubation experiment and two pot trials were...... conducted. Generally, biochar caused decreased soil NO3−availability and N use efficiency, and reduced biomass yields compared to a control soil. Soil NO3−concentrations were more reduced in the willow compared to the pine biochar treatments and the reduction increased with increasing pyrolysis temperatures...

  11. The Relations Between Soil Water Retention Characteristics, Particle Size Distributions, Bulk Densities and Calcium Carbonate Contents for Danish Soils

    DEFF Research Database (Denmark)

    Jensen, Niels H.; Balstrøm, Thomas; Breuning-Madsen, Henrik

    2005-01-01

    A database containing about 800 soil profiles located in a 7-km grid covering Denmark has been used to develop a set of regression equations of soil water content at pressure heads –1, -10, -100 and –1500 kPa versus particle size distribution, organic matter, CaCO3 and bulk density. One purpose...... was to elaborate equations based of soil parameters available in the Danish Soil Classification's texture database on particle size distribution and organic matter. It was also tested if inclusion of bulk density or CaCO3 content (in CaCO3-containing samples) as predictors or grouping in surface and subsurface...... horizons or textural classes improved the regression equations. Compared to existing Danish equations based on much fewer observations the accuracies of the new equations were better. The equations also predicted the soil water content at the measured pressure heads more accurate than the pedotransfer...

  12. Development of Soil Characteristics and Plant Communities On Reclaimed and Unreclaimed Spoil Heaps After Coal Mining

    Science.gov (United States)

    Cudlín, Ondřej; Řehák, Zdeněk; Cudlín, Pavel

    2016-10-01

    The aim of this study was to compare soil characteristics, plant communities and the rate of selected ecosystem function performance on reclaimed and unreclaimed plots (left for spontaneous succession) of different age on spoil heaps. Twelve spoil heaps (three circle plots of radius 12.5 m) near the town Kladno in north-west direction from Prague, created after deep coal mining, were compared. Five mixed soil samples from organo-mineral horizons in each plot were analysed for total content of carbon, nitrogen and phosphorus. In addition, active soil pH (pHH2O) was determined. Plant diversity was determined by vegetation releves. The biodiversity value of the habitat according to the Habitat Valuation Method was assessed and the rate of evapotranspiration function by the Method of Valuation Functions and Services of Ecosystems in the Czech Republic were determined. The higher organo-mineral layers and higher amount of total nitrogen content were found on the older reclaimed and unreclaimed plots than in younger plots. The number of plant species and the total contents of carbon and nitrogen were significantly higher at the unreclaimed plots compared to reclaimed plots. The biodiversity values and evapotranspiration function rate were also higher on unreclaimed plots. From this perspective, it is possible to recommend using of spontaneous succession, together with routine reclamation methods to restore habitats after coal mining. Despite the relatively high age of vegetation in some of selected plots (90 years), both the reclaimed and unreclaimed plots have not reached the stage of potential vegetation near to natural climax. Slow development of vegetation was probably due to unsuitable substrate of spoil heaps and a lack of plant and tree species of natural forest habitats in this area. However, it is probable that vegetation communities on observed spoil heaps in both type of management (reclaimed and unreclaimed) will achieve the stage of natural climax and they

  13. Effect of Underground Saline Water on the Growth Characteristic of Tamarix austromongolica in Halomorphic Soil

    Science.gov (United States)

    Iwama, Kenji; Kobayashi, Koji; Kaneki, Ryoichi; Furukawa, Masayuki; Odani, Hiromichi

    It is important to evaluate the salt tolerance of native plants in order to utilize them for improving halomorphic soil in arid regions. Tamarix austromongolica, a dominant species in Inner Mongolia, China, has the property of salt absorption and expected soil desalinization. The effect of salt concentration in groundwater on the growth of stock diameter and shoot length were evaluated by cultivation experiments, growing the plants from cuttings for two years. Though the plants grew well in 1% salt concentration of groundwater, the evapotranspiration in the second year was reduced because of the growth of the root system. The growth of the plants and evapotranspiration were reduced with increasing groundwater salinity of 3 to 5%, but most plants did not die. In contrast, the plants which were supplied with groundwater of 7% salt concentration in the second year started to die in about a month, and two thirds of them died within five months. Thus the results showed that the tolerant limit of salinity of the plants in groundwater was 7%, and the growth was constrained with groundwater salinity of 3 to 5% concentration. The plants that survived with 7% salinity in the second year, however, were grown in groundwater salt concentration of 3% to 5% in the first year. This result indicated that saline stress might have changed the characteristic of salinity tolerance of the plant.

  14. Footprint characteristics revised for field-scale soil moisture monitoring with cosmic-ray neutrons

    Science.gov (United States)

    Köhli, M.; Schrön, M.; Zreda, M.; Schmidt, U.; Dietrich, P.; Zacharias, S.

    2015-07-01

    Cosmic-ray neutron probes are widely used to monitor environmental water content near the surface. The method averages over tens of hectares and is unrivaled in serving representative data for agriculture and hydrological models at the hectometer scale. Recent experiments, however, indicate that the sensor response to environmental heterogeneity is not fully understood. Knowledge of the support volume is a prerequisite for the proper interpretation and validation of hydrogeophysical data. In a previous study, several physical simplifications have been introduced into a neutron transport model in order to derive the characteristics of the cosmic-ray probe's footprint. We utilize a refined source and energy spectrum for cosmic-ray neutrons and simulate their response to a variety of environmental conditions. Results indicate that the method is particularly sensitive to soil moisture in the first tens of meters around the probe, whereas the radial weights are changing dynamically with ambient water. The footprint radius ranges from 130 to 240 m depending on air humidity, soil moisture, and vegetation. The moisture-dependent penetration depth of 15 to 83 cm decreases exponentially with distance to the sensor. However, the footprint circle remains almost isotropic in complex terrain with nearby rivers, roads or hill slopes. Our findings suggest that a dynamically weighted average of point measurements is essential for accurate calibration and validation. The new insights will have important impact on signal interpretation, sensor installation, data interpolation from mobile surveys, and the choice of appropriate resolutions for data assimilation into hydrological models.

  15. Effects of silicon on photosynthetic characteristics of maize (Zea mays L.) on alluvial soil.

    Science.gov (United States)

    Xie, Zhiming; Song, Fengbin; Xu, Hongwen; Shao, Hongbo; Song, Ri

    2014-01-01

    The objectives of the study were to determine the effects of silicon on photosynthetic characteristics of maize on alluvial soil, including total chlorophyll contents, photosynthetic rate (P n), stomatal conductance (g s), transpiration rate (E), and intercellular CO2 concentration (C i ) using the method of field experiment, in which there were five levels (0, 45, 90, 150, and 225 kg · ha(-1)) of silicon supplying. The results showed that certain doses of silicon fertilizers can be used successfully in increasing the values of total chlorophyll contents, P n, and g s and decreasing the values of E and C i of maize leaves, which meant that photosynthetic efficiency of maize was significantly increased in different growth stages by proper doses of Si application on alluvial soil, and the optimal dose of Si application was 150 kg · ha(-1). Our results indicated that silicon in proper amounts can be beneficial in increasing the photosynthetic ability of maize, which would be helpful for the grain yield and growth of maize.

  16. Soil-water characteristics of Gaomiaozi bentonite by vapour equilibrium technique

    Directory of Open Access Journals (Sweden)

    Wenjing Sun

    2014-02-01

    Full Text Available Soil-water characteristics of Gaomiaozi (GMZ Ca-bentonite at high suctions (3–287 MPa are measured by vapour equilibrium technique. The soil-water retention curve (SWRC of samples with the same initial compaction states is obtained in drying and wetting process. At high suctions, the hysteresis behaviour is not obvious in relationship between water content and suction, while the opposite holds between degree of saturation and suction. The suction variation can change its water retention behaviour and void ratio. Moreover, changes of void ratio can bring about changes in degree of saturation. Therefore, the total change in degree of saturation includes changes caused by suction and that by void ratio. In the space of degree of saturation and suction, the SWRC at constant void ratio shifts to the direction of higher suctions with decreasing void ratio. However, the relationship between water content and suction is less affected by changes of void ratio. The degree of saturation decreases approximately linearly with increasing void ratio at a constant suction. Moreover, the slope of the line decreases with increasing suction and they show an approximately linear relationship in semi-logarithmical scale. From this linear relationship, the variation of degree of saturation caused by the change in void ratio can be obtained. Correspondingly, SWRC at a constant void ratio can be determined from SWRC at different void ratios.

  17. Implementing a physical soil water flow model with minimal soil characteristics and added value offered by surface soil moisture measurements assimilation.

    Science.gov (United States)

    Chanzy, André

    2010-05-01

    Soil moisture is a key variable for many soil physical and biogeochemical processes. Its dynamic results from water fluxes in soil and at its boundaries, as well as soil water storage properties. If the water flows are dominated by diffusive processes, modelling approaches based on the Richard's equation or the Philip and de Vries coupled heat and water flow equations lead to a satisfactory representation of the soil moisture dynamic. However, It requires the characterization of soil hydraulic functions, the initialisation and the boundary conditions, which are expensive to obtain. The major problem to assess soil moisture for decision making or for representing its spatiotemporal evolution over complex landscape is therefore the lack of information to run the models. The aim of the presentation is to analyse how a soil moisture model can be implemented when only climatic data and basic soil information are available (soil texture, organic matter) and what would be the added of making a few soil moisture measurements. We considered the field scale, which is the key scale for decision making application (the field being the management unit for farming system) and landscape modelling (field size being comparable to the computation unit of distributed hydrological models). The presentation is limited to the bare soil case in order to limit the complexity of the system and the TEC model based on Philip and De Vries equations is used in this study. The following points are addressed: o the within field spatial variability. This spatial variability can be induced by the soil hydraulic properties and/or by the amount of infiltrated water induced by water rooting towards infiltration areas. We analyse how an effective parameterization of soil properties and boundary conditions can be used to simulate the field average moisture. o The model implementation with limited information. We propose strategies that can be implemented when information are limited to soil texture and

  18. Soil structure and characteristics of organic matter in two orchards differing in eartworm activity

    NARCIS (Netherlands)

    Jongmans, A.G.; Pulleman, M.M.; Balabane, M.; Oort, van F.; Marinissen, J.C.Y.

    2003-01-01

    By consuming plant remains and soil, earthworms incorporate organic matter (OM) into the soil and form biogenic soil structures, which can affect OM dynamics. We carried out a (micro)morphological study of soil structure development and OM distribution in two orchards (45 year) in a Dutch calcareous

  19. Significance of frost action and surface soil characteristics to wind erosion at Rocky Flats, Colorado. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Caine, N.

    1978-09-01

    This study of the potential links between soil freezing and wind erosion was conducted at Rocky Flats during 4 winters. Most of the study has involved the conditions leading to the growth of segregation ice in the surface soil and the ground heave which that produces. This occurs about 15 times in the average winter at Rocky Flats, always on a diurnal cycle. Such frost action is preferentially distributed in time and space and cannot be estimated from air temperatures alone. November and March are the months of most frequent frost heave, and then only in the days following precipitation or snowmelt. The most marked frost effects are found on exposed interfluve and hillcrest situations, where there are patches of bare soil. Almost no effects are found on the valley floors. Soil disturbance by segregation ice leads to a marked decrease in soil bulk density, and presumably in soil strength though this change has not been quantitatively defined. However, this does not lead to wind erosion of the soil at the study site because that surface is more influenced by the vegetation cover than by the soil characteristics.

  20. Quantitative Analysis of Relevant Soil, Land-use and Climate Characteristics on Landscape Degradation in Hungary

    Science.gov (United States)

    Kertesz, Adam; Mika, Janos; Jakab, Gergely; Palinkas, Melinda

    2017-04-01

    The objective of our research is to survey degradation processes acting in each micro-region of Hungary in connection with geographical and climatic characteristics. A survey of land degradation processes has been carried out at medium scale (1:50 000) to identify the affected areas of the region. Over 18,000 rectangles of Hungary have been digitally characterised for several types of land degradation. Water-flow type gully erosion and soil-loss (RUSLE, 2015: Esdac-data) are studied for dependent variables in this study. USDA textural classes, available water capacity, bulk density, clay content, coarse fragments, silt content, sand content, soil parent material, soil texture, land-use type (Corine, 2012) are used for non-climatic variables. Some of these characteristics are quantified in a non-scalable way, so the first step was to arrange these qualitative codes or pseudo-numbers into monotonous order for including them into the following multi-regression analyses. Data available from the CarpatClim Project (www.carpatclim-eu.org/pages/home) for 1961-2010 are also used in their 50 years averages is seasonal and annual resolution. The selected variables from this gridded data set are global radiation, daily mean temperature, maximum and minimum temperature, number of extreme cold days (20 mm), days with utilizable precipitation (>1mm/d), potential evapotranspiration, Palmer Index (PDSI), Palfai Index (PAI), relative humidity and wind speed at 10 m height. The gully erosion processes strongly depend on the investigated non-climatic variables, mostly on parent material and slope. The group of further climatic factors is formed by winter relative humidity, wind speed and all-year round Palmer index. Besides leading role of the above non-climatic factors, additional effects of the significant climate variables are difficult to interpret. Nevertheless, the partial effects of these climate variables are combined with future climate scenarios available from GCM and RCM

  1. Enhanced DEA model with undesirable output and interval data for rice growing farmers performance assessment

    Energy Technology Data Exchange (ETDEWEB)

    Khan, Sahubar Ali Mohd. Nadhar, E-mail: sahubar@uum.edu.my; Ramli, Razamin, E-mail: razamin@uum.edu.my; Baten, M. D. Azizul, E-mail: baten-math@yahoo.com [School of Quantitative Sciences, UUM College of Arts and Sciences, Universiti Utara Malaysia, 06010 Sintok, Kedah (Malaysia)

    2015-12-11

    Agricultural production process typically produces two types of outputs which are economic desirable as well as environmentally undesirable outputs (such as greenhouse gas emission, nitrate leaching, effects to human and organisms and water pollution). In efficiency analysis, this undesirable outputs cannot be ignored and need to be included in order to obtain the actual estimation of firms efficiency. Additionally, climatic factors as well as data uncertainty can significantly affect the efficiency analysis. There are a number of approaches that has been proposed in DEA literature to account for undesirable outputs. Many researchers has pointed that directional distance function (DDF) approach is the best as it allows for simultaneous increase in desirable outputs and reduction of undesirable outputs. Additionally, it has been found that interval data approach is the most suitable to account for data uncertainty as it is much simpler to model and need less information regarding its distribution and membership function. In this paper, an enhanced DEA model based on DDF approach that considers undesirable outputs as well as climatic factors and interval data is proposed. This model will be used to determine the efficiency of rice farmers who produces undesirable outputs and operates under uncertainty. It is hoped that the proposed model will provide a better estimate of rice farmers’ efficiency.

  2. Distinct oxytocin effects on belief updating in response to desirable and undesirable feedback

    Science.gov (United States)

    Ma, Yina; Li, Shiyi; Wang, Chenbo; Liu, Yi; Li, Wenxin; Yan, Xinyuan; Chen, Qiang; Han, Shihui

    2016-01-01

    Humans update their beliefs upon feedback and, accordingly, modify their behaviors to adapt to the complex, changing social environment. However, people tend to incorporate desirable (better than expected) feedback into their beliefs but to discount undesirable (worse than expected) feedback. Such optimistic updating has evolved as an advantageous mechanism for social adaptation. Here, we examine the role of oxytocin (OT)―an evolutionary ancient neuropeptide pivotal for social adaptation―in belief updating upon desirable and undesirable feedback in three studies (n = 320). Using a double-blind, placebo-controlled between-subjects design, we show that intranasally administered OT (IN-OT) augments optimistic belief updating by facilitating updates of desirable feedback but impairing updates of undesirable feedback. The IN-OT–induced impairment in belief updating upon undesirable feedback is more salient in individuals with high, rather than with low, depression or anxiety traits. IN-OT selectively enhances learning rate (the strength of association between estimation error and subsequent update) of desirable feedback. IN-OT also increases participants’ confidence in their estimates after receiving desirable but not undesirable feedback, and the OT effect on confidence updating upon desirable feedback mediates the effect of IN-OT on optimistic belief updating. Our findings reveal distinct functional roles of OT in updating the first-order estimation and second-order confidence judgment in response to desirable and undesirable feedback, suggesting a molecular substrate for optimistic belief updating. PMID:27482087

  3. Enhanced DEA model with undesirable output and interval data for rice growing farmers performance assessment

    Science.gov (United States)

    Khan, Sahubar Ali Mohd. Nadhar; Ramli, Razamin; Baten, M. D. Azizul

    2015-12-01

    Agricultural production process typically produces two types of outputs which are economic desirable as well as environmentally undesirable outputs (such as greenhouse gas emission, nitrate leaching, effects to human and organisms and water pollution). In efficiency analysis, this undesirable outputs cannot be ignored and need to be included in order to obtain the actual estimation of firms efficiency. Additionally, climatic factors as well as data uncertainty can significantly affect the efficiency analysis. There are a number of approaches that has been proposed in DEA literature to account for undesirable outputs. Many researchers has pointed that directional distance function (DDF) approach is the best as it allows for simultaneous increase in desirable outputs and reduction of undesirable outputs. Additionally, it has been found that interval data approach is the most suitable to account for data uncertainty as it is much simpler to model and need less information regarding its distribution and membership function. In this paper, an enhanced DEA model based on DDF approach that considers undesirable outputs as well as climatic factors and interval data is proposed. This model will be used to determine the efficiency of rice farmers who produces undesirable outputs and operates under uncertainty. It is hoped that the proposed model will provide a better estimate of rice farmers' efficiency.

  4. Distinct oxytocin effects on belief updating in response to desirable and undesirable feedback.

    Science.gov (United States)

    Ma, Yina; Li, Shiyi; Wang, Chenbo; Liu, Yi; Li, Wenxin; Yan, Xinyuan; Chen, Qiang; Han, Shihui

    2016-08-16

    Humans update their beliefs upon feedback and, accordingly, modify their behaviors to adapt to the complex, changing social environment. However, people tend to incorporate desirable (better than expected) feedback into their beliefs but to discount undesirable (worse than expected) feedback. Such optimistic updating has evolved as an advantageous mechanism for social adaptation. Here, we examine the role of oxytocin (OT)-an evolutionary ancient neuropeptide pivotal for social adaptation-in belief updating upon desirable and undesirable feedback in three studies (n = 320). Using a double-blind, placebo-controlled between-subjects design, we show that intranasally administered OT (IN-OT) augments optimistic belief updating by facilitating updates of desirable feedback but impairing updates of undesirable feedback. The IN-OT-induced impairment in belief updating upon undesirable feedback is more salient in individuals with high, rather than with low, depression or anxiety traits. IN-OT selectively enhances learning rate (the strength of association between estimation error and subsequent update) of desirable feedback. IN-OT also increases participants' confidence in their estimates after receiving desirable but not undesirable feedback, and the OT effect on confidence updating upon desirable feedback mediates the effect of IN-OT on optimistic belief updating. Our findings reveal distinct functional roles of OT in updating the first-order estimation and second-order confidence judgment in response to desirable and undesirable feedback, suggesting a molecular substrate for optimistic belief updating.

  5. [Changes in vegetation and soil characteristics under tourism disturbance in lakeside wetland of northwest Yunnan Plateau, Southwest China].

    Science.gov (United States)

    Tang, Ming-Yan; Yang, Yong-Xing

    2014-05-01

    The characteristics of vegetation and soil were investigated in Bita Lake and Shudu Lake wetlands in northwest Yunnan Plateau under tourism disturbance. The 22 typical plots in the wetlands were classified into 4 types by TWINSPAN, including primary wetland, light degradation, moderate degradation, and severe degradation. Along the degradation gradient, the plant community density, coverage, species number and Shannon diversity index increased and the plant height decreased in Bita Lake and Shudu Lake wetlands, and Whittaker diversity index increased in Bita Lake wetland. Plant species number, soil organic matter, total nitrogen, porosity, available nitrogen, available phosphorus and available potassium contents were higher in Shudu Lake wetland than in Bita Lake wetland, but the plant density, height, soil total potassium and pH were opposite. Canonical correspondence analysis (CCA) by importance values of 42 plants and 11 soil variables showed that soil organic matter, total nitrogen and total potassium were the key factors on plant species distribution in Bita Lake and Shudu Lake wetlands under tourism disturbance. TWINSPAN classification and analysis of vegetation-soil characteristics indicated the effects of tourism disturbance in Bita Lake wetland were larger than in Shudu Lake wetland.

  6. Micromorphological characteristics of sandy forest soils recently impacted by wildfires in Russia

    Science.gov (United States)

    Maksimova, Ekaterina; Abakumov, Evgeny

    2017-04-01

    Two fire-affected soils were studied using micromorphological methods. The objective of the paper is to assess and compare fire effects on the micropedological organisation of soils in a forest-steppe zone of central Russia (Volga Basin, Togliatti city). Samples were collected in the green zone of Togliatti city. The results showed that both soils were rich in quartz and feldspar. Mica was highly present in soils affected by surface fires, while calcium carbonates were identified in the soils affected by crown fires. The type of plasma is humus-clay, but the soil assemblage is plasma-silt with a prevalence of silt. Angular and subangular grains are the most dominant soil particulates. No evidence of intensive weathering was detected. There was a decrease in the porosity of soils affected by fires as a consequence of soil pores filled with ash and charcoal.

  7. [Characteristics of Phthalic Acid Esters in Agricultural Soils and Products in Areas of Zhongshan City, South China].

    Science.gov (United States)

    Li, Bin; Wu, Shan; Liang, Jin-ming; Liang, Wen-li; Chen, Gui-xian; Li, Yong-jun; Yang, Guo-yi

    2015-06-01

    significant difference for single PAEs compound accumulated by agricultural products, the ∑ PAEs bioconcentration factors of all agricultural products were above 1. Therefore, the accumulation characteristics of PAEs should be fully concerned when farm soil quality assessment is taken.

  8. Soil characteristics of a hyperseasonal cerrado compared to a seasonal cerrado and a floodplain grassland: implications for plant community structure.

    Science.gov (United States)

    Amorim, P K; Batalha, M A

    2006-05-01

    Savannas may be divided according to their seasonality into semi-seasonal, seasonal, hyperseasonal, or marshy savannas. Hyperseasonal savannas are characterized by the alternation of two contrasting stresses during each annual cycle, one induced by drought and fire and the other, by waterlogging. In South America, the largest savanna region is the Brazilian cerrado, in which there are few hyperseasonal areas that become waterlogged in the rainy season. The cerrado soils are generally well drained, but in central Brazil there is a small cerrado area in which the soil is poorly drained and which becomes waterlogged in the middle of the rainy season, allowing the appearance of a hyperseasonal cerrado. As long as soil is important in the ecology of the cerrado vegetation, we asked whether the waterlogging in this hyperseasonal cerrado implied that there were differences in soil characteristics in relation to a seasonal cerrado, which is not waterlogged in the rainy season, and to a floodplain grassland, which remains waterlogged throughout the year. In each environment, we randomly selected ten points, in which we collected soil samples in the mid-rainy season for chemical and granulometric analyses. For all variables, we found significant differences among the three environments, at least at one of the depths. Nevertheless, when we took into account all the variables together, we observed that the soils under the hyperseasonal and seasonal cerrados were similar and both were different to the soil under the floodplain grassland. The soil under the floodplain grassland was related to larger amounts of clay, silt, organic matter, phosphorus, aluminium, aluminium saturation, cation exchange capacity, and sum of bases, whereas soils under hyperseasonal and seasonal cerrados were related to higher pH values, base saturation, calcium, magnesium, and sand. As long as the soil under both cerrados was chemically and physically similar, the duration of waterlogging in the

  9. Soil characteristics of a hyperseasonal cerrado compared to a seasonal cerrado and a floodplain grassland: implications for plant community structure

    Directory of Open Access Journals (Sweden)

    P. K. Amorim

    Full Text Available Savannas may be divided according to their seasonality into semi-seasonal, seasonal, hyperseasonal, or marshy savannas. Hyperseasonal savannas are characterized by the alternation of two contrasting stresses during each annual cycle, one induced by drought and fire and the other, by waterlogging. In South America, the largest savanna region is the Brazilian cerrado, in which there are few hyperseasonal areas that become waterlogged in the rainy season. The cerrado soils are generally well drained, but in central Brazil there is a small cerrado area in which the soil is poorly drained and which becomes waterlogged in the middle of the rainy season, allowing the appearance of a hyperseasonal cerrado. As long as soil is important in the ecology of the cerrado vegetation, we asked whether the waterlogging in this hyperseasonal cerrado implied that there were differences in soil characteristics in relation to a seasonal cerrado, which is not waterlogged in the rainy season, and to a floodplain grassland, which remains waterlogged throughout the year. In each environment, we randomly selected ten points, in which we collected soil samples in the mid-rainy season for chemical and granulometric analyses. For all variables, we found significant differences among the three environments, at least at one of the depths. Nevertheless, when we took into account all the variables together, we observed that the soils under the hyperseasonal and seasonal cerrados were similar and both were different to the soil under the floodplain grassland. The soil under the floodplain grassland was related to larger amounts of clay, silt, organic matter, phosphorus, aluminium, aluminium saturation, cation exchange capacity, and sum of bases, whereas soils under hyperseasonal and seasonal cerrados were related to higher pH values, base saturation, calcium, magnesium, and sand. As long as the soil under both cerrados was chemically and physically similar, the duration of

  10. Characteristics of soil stability and carbon sequestration under water storage and drainage model

    Science.gov (United States)

    Li, J.; Han, J. C.; Chen, C.; Yang, J. J.

    2017-07-01

    This research was conducted to investigate the influence of saline alkali soil on soil physical properties, stability and organic carbon storage under water storage and drainage, and to provide scientific basis for improving soil quality in Fuping County of Shaanxi Province, China. Saline alkali soil model test was conducted and the process was assessed with two different methods: i) traditional drainage and ecological water storage, measure and analyze 0-30 cm soil bulk density, porosity, field water capacity, mean mass diameter (MWD), geological mean diameter (GMD), stability of water stable aggregate (WASR), aggregate destruction rate (PAD), fractal dimension (D) and; ii) organic carbon storage, comprehensively analyze the relationship between stability index and soil organic carbon. The results show that: (1) compared with traditional drainage treatment, water treatment may effectively reduce the soil bulk density by 1.3%-4.2%, and improve soil porosity and field capacity at the same time; (2) under dry and wet screen treatment, soil stability, the water storing treatment is higher than the drainage treatment. Performance trend of soil MWD and GMD increases with the increase of soil depth. The stability of soil water stable aggregates increased 14.5%-53.4%. The average aggregate destruction rate was 3.2% lower than that of the drainage treatment and the difference is obvious (Pfractal dimension and soil organic carbon storage. The correlation coefficient is, respectively, R2=0.86 and R2=0.94, and the difference is obvious (P<0.05). To sum up, the water storage treatment can effectively improve the soil quality, improve soil stability and soil organic carbon storage, which can be a good control of saline alkali soil.

  11. The significance of soil moisture in forecasting characteristics of flood events. A statistical analysis in two nested catchments

    Directory of Open Access Journals (Sweden)

    Chifflard Peter

    2018-03-01

    Full Text Available We examine the feasibility and added value of upscaling point data of soil moisture from a small- to a mesoscale catchment for the purpose of single-event flood prediction. We test the hypothesis that in a given catchment, the present soil moisture status is a key factor governing peak discharge, flow volume and flood duration. Multiple regression analyses of rainfall, pre-event discharge, single point soil moisture profiles from representative locations and peak discharge, discharge duration, discharge volume are discussed. The soil moisture profiles are selected along a convergent slope connected to the groundwater in flood plain within the small-scale catchment Husten (2.6 km², which is a headwater catchment of the larger Hüppcherhammer catchment (47.2 km², Germany. Results show that the number of explanatory variables in the regression models is higher in summer (up to 8 variables than in winter (up to 3 variables and higher in the meso-scale catchment than in the small-scale catchment (up to 2 variables. Soil moisture data from selected key locations in the small catchment improves the quality of regression models established for the meso-scale catchment. For the different target variables peak discharge, discharge duration and discharge volume the adding of the soil moisture from the flood plain and the lower slope as explanatory variable improves the quality of the regression model by 15%, 20% and 10%, respectively, especially during the summer season. In the winter season the improvement is smaller (up to 6% and the regression models mainly include rainfall characteristics as explanatory variables. The appearance of the soil moisture variables in the stepwise regression indicates their varying importance, depending on which characteristics of the discharge are focused on. Thus, we conclude that point data for soil moisture in functional landscape elements describe the catchments’ initial conditions very well and may yield valuable

  12. Short-Term Effect of Feedstock and Pyrolysis Temperature on Biochar Characteristics, Soil and Crop Response in Temperate Soils

    Directory of Open Access Journals (Sweden)

    Victoria Nelissen

    2014-01-01

    Full Text Available At present, there is limited understanding of how biochar application to soil could be beneficial to crop growth in temperate regions and which biochar types are most suitable. Biochar’s (two feedstocks: willow, pine; three pyrolysis temperatures: 450 °C, 550 °C, 650 °C effect on nitrogen (N availability, N use efficiency and crop yield was studied in northwestern European soils using a combined approach of process-based and agronomic experiments. Biochar labile carbon (C fractions were determined and a phytotoxicity test, sorption experiment, N incubation experiment and two pot trials were conducted. Generally, biochar caused decreased soil NO3− availability and N use efficiency, and reduced biomass yields compared to a control soil. Soil NO3− concentrations were more reduced in the willow compared to the pine biochar treatments and the reduction increased with increasing pyrolysis temperatures, which was also reflected in the biomass yields. Woody biochar types can cause short-term reductions in biomass production due to reduced N availability. This effect is biochar feedstock and pyrolysis temperature dependent. Reduced mineral N availability was not caused by labile biochar C nor electrostatic NH4+/NO3− sorption. Hence, the addition of fresh biochar might in some cases require increased fertilizer N application to avoid short-term crop growth retardation.

  13. The Soil Characteristic Curve at Low Water Contents: Relations to Specific Surface Area and Texture

    DEFF Research Database (Denmark)

    Resurreccion, Augustus; Møldrup, Per; Schjønning, Per

    Accurate description of the soil-water retention curve (SWRC) at low water contents is important for simulating water dynamics, plant-water relations, and microbial processes in surface soil. Soil-water retention at soil-water matric potential of less than -10 MPa, where adsorptive forces dominate...... that measurements by traditional pressure plate apparatus generally overestimated water contents at -1.5 MPa (plant wilting point). The 41 soils were classified into four textural classes based on the so-called Dexter index n (= CL/OC), and the Tuller-Or (TO) general scaling model describing the water film...... thickness at a given soil-water matric potential (low organic soils with n > 10, the estimated SA from the dry soil-water retention was in good agreement with the SA measured using ethylene glycol monoethyl ether (SA_EGME). A strong relationship between the ratio...

  14. Evaluation of consolidation characteristics of cohesive soils from piezocone penetration tests.

    Science.gov (United States)

    2004-01-01

    The piezocone penetration test (PCPT) has gained wide popularity and acknowledgement as a preferred in-situ device for subsurface investigation and soil characterization. The PCPT measurements can be utilized for soil identification and the evaluatio...

  15. [Nutrient Characteristics and Nitrogen Forms of Rhizosphere Soils Under Four Typical Plants in the Littoral Zone of TGR].

    Science.gov (United States)

    Wang, Xiao-feng; Yuan, Xing-zhong; Liu, Hong; Zhang, Lei; Yu, Jian-jun; Yue, Jun-sheng

    2015-10-01

    The Three Gorges Reservoir (TGR), which is the largest water conservancy project ever built in tne world, produced a drawdown area of about 348.93 km2 because of water level control. The biological geochemical cycle of the soil in the drawdown zone has been changed as the result of long-term winter flooding and summer drought and vegetation covering. The loss of soil nitrogen in the drawdown zone poses a threat to the water environmental in TGR. Pengxi river, is an important anabranch, which has the largest drawdown area has been selected in the present study. The four typical vegetation, contained Cynodon dactylon, Cyperus rotundus, Anthium sibiricum and Zea mays L. as the control, were studied to measure nutrient characteristics and nitrogen forms of rhizosphere and non-rhizosphere soils in three distribution areas with different soil types (paddy soil, purple soil and fluvo-aquic soils). The variables measured included organic matter (OM), total nitrogen (TN), total phosphorus (TP), total potassium (TK), hydrolysis N, available P and available K, pH, ion-exchangeable N (IEE-N), weak acid extractable N (CF-N) , iron-manganese oxides N (IMOF-N), organic matter sulfide N (OSF-N), added up four N forms for total transferable N (TF-N) and TN minus TF-N for non-transferable N (NTF-N). The results showed: (1) pH of rhizosphere soil was generally lower than that of non-rhizosphere soil under different vegetation in different type soils because the possible organic acid and H+ released form plant roots and cation absorption differences, and the OM, TP, TN and hydrolysis N of rhizosphere soil were generally higher than those of non-rhizosphere soil, and that the enrichment ratio (ER) of all the four nutrient indicators showed Cyperus rotundus > Cynodon dactylon > Zea mays L. > Anthium sibiricum. Available P showed enrichment in the rhizosphere of three natural vegetations but lose under corn, and available K, TK showed different ER in different conditions. (2) IEF-N CF

  16. Characteristics and classification of the soils of the plateau of SIMEN ...

    African Journals Online (AJOL)

    North Gonder). Detailed soil survey (scale 1:25 000) was conducted to classify, characterise and determine status of the soils of the plateau of smnp. Umbric Andosols, Luvic Andosols and Mollic-Lithic Leptosols were found to be the major soil ...

  17. [Sap flow characteristics of Quercus liaotungensis in response to sapwood area and soil moisture in the loess hilly region, China].

    Science.gov (United States)

    Lyu, Jin Lin; He, Qiu Yue; Yan, Mei Jie; Li, Guo Qing; Du, Sheng

    2018-03-01

    To examine the characteristics of sap flow in Quercus liaotungensis and their response to environmental factors under different soil moisture conditions, Granier-type thermal dissipation probes were used to measure xylem sap flow of trees with different sapwood area in a natural Q. liaotungensis forest in the loess hilly region. Solar radiation, air temperature, relative air humidity, precipitation, and soil moisture were monitored during the study period. The results showed that sap flux of Q. liaotungensis reached daily peaks earlier than solar radiation and vapor pressure deficit. The diurnal dynamics of sap flux showed a similar pattern to those of the environmental factors. Trees had larger sap flux during the period with higher soil moisture. Under the same soil moisture conditions, trees with larger diameter and sapwood areas had significantly higher sap flux than those with smaller diameter and sapwood areas. Sap flux could be fitted with vapor pressure deficit, solar radiation, and the integrated index of the two factors using exponential saturation function. Differences in the fitted curves and parameters suggested that sap flux tended to reach saturation faster under higher soil moisture. Furthermore, trees in the smaller diameter class were more sensitive to the changes of soil moisture. The ratio of daily sap flux per unit vapor pressure deficit under lower soil moisture condition to that under higher soil moisture condition was linearly correlated to sapwood area. The regressive slope in smaller diameter class was larger than that in bigger diameter class, which further indicated the higher sensitivity of trees with smaller diameter class to soil moisture. These results indicated that wider sapwood of larger diameter class provided a buffer against drought stress.

  18. The Characteristics of Soil N Accumulation and Movement in Different Farmlands in the Yellow River Irrigation Region of Ningxia, China

    Directory of Open Access Journals (Sweden)

    KE Ying

    2014-02-01

    Full Text Available The greenhouse fields(n=4and open fields with rotation of paddy-upland crops(n=4were chosen in the Yellow River Irrigation Region of Ningxia. A method of multiple-points field sampling investigation and laboratory analysis was conducted to study the charac-teristics of soil N accumulation and distribution in different soil profiles and its movement effect on N content in the shallow groundwater from two different farmlands. The results indicated that total soluble N(TSN, NO3--N and soluble organic N(SONcontents in 0~150 cm soil in greenhouse fields were significantly higher than that in open fields, and the average contents in the former fields were 1.5~5.6, 1.5~3.4, 1.6~9.8 times as that in the latter fields, respectively. Different forms of N were mainly accumulated in 0~5 cm and 5~20 cm soil depth in green-house fields, and which were accumulated in 40~100 cm soil depth in open fields. Soil TSN accounted for TN by 5.4%~11.5% and 2.2%~4.9% in the greenhouse and open fields, respectively, and the former had a higher risk of soil N leaching losses. Different forms of dissolved N accumulation amount were SON>NO3--N>NH4+-N in 0~150 cm soil in greenhouse fields, and with the order of NO3--N>SON>NH4+-N in open fields. The TSN, NO3--N and SON contents in the shallow groundwater in greenhouse fields were also significantly higher than that in open fields, the former were 9.5, 13.8, 7.0 times as that in the latter, respectively. Therefore, both NO3--N and SON could be important soil N accumulation forms in these two different farmlands, and that may pollute the shallow groundwater in these two different fields.

  19. [Distribution characteristic and assessment of soil heavy metal pollution in the iron mining of Baotou in Inner Mongolia].

    Science.gov (United States)

    Guo, Wei; Zhao, Ren-Xin; Zhang, Jun; Bao, Yu-Ying; Wang, Hong; Yang, Ming; Sun, Xiao-Li; Jin, Fan

    2011-10-01

    The pollution status and total concentration of soil heavy metals were analyzed around tailing reservoir of Baotou and iron mining of Bayan Obo located in Inner Mongolia grassland ecosystem. Aim of the study is to control soil heavy metal pollution of grassland mining area and provide the basic information. The results indicated that the soils from different directions of the tailing reservoir were contaminated by Pb, Cu, Zn and Mn. According to the single factor pollution index, the pollution degree was Mn > Zn > Pb > Cu. According to Nemerow integrated pollution index, the indexes of the northeast, southeast, southwest, and northwest of the tailing reservoir, were 2.43, 10.2, 1.88, 1.64. Soils from the southeast had the most serious heavy metal contamination because of the dominant wind of northwest. Within 50 m from the edge of tailing reservoir, heavy metal contamination was most serious except Cu. With regard to Bayan Obo iron mining, the single factor pollution index indicated that the soils from the six surveyed regions were contaminated by Pb, Cu, Zn and Mn. The integrated pollution index indicated that the indexes of the six regions, such as the mining area, the dump, outside the dump, outside the urban area, east region of the railway, and west region of the railway, were 14.3, 4.30, 2.69, 3.41, 2.88, and 2.20, respectively. The soil pollution degree of the mining area was the highest. Additionally, the transport of ore resulted in soil heavy metal pollution along railway. In general, soils of the two studied areas had the similar pollution characteristic, and the elements of heavy metal contamination were corresponding with the concentrations of tailings. The health and stabilization of grassland ecosystem are being threatened by soil heavy metals.

  20. Effects of humic acid-based buffer + cation on chemical characteristics of saline soils and maize growth

    Directory of Open Access Journals (Sweden)

    W. Mindari

    2014-10-01

    Full Text Available Humic acid is believed to maintain the stability of the soil reaction, adsorption / fixation / chelate of cation, thereby increasing the availability of water and plant nutrients. On the other hand, the dynamics of saline soil cation is strongly influenced by the change of seasons that disrupt water and plant nutrients uptake. This experiment was aimed to examine the characteristics of the humic acid from compost, coal, and peat and its function in the adsorption of K+ and NH4+ cations, thus increasing the availability of nutrients and of maize growth. Eighteen treatments consisted of three humic acid sources (compost, peat and coal, two cation additives (K+ and NH4+, and three doses of humic acid-based buffer (10, 20, and 30 g / 3kg, were arranged in a factorial completely randomized with three replicates. The treatments were evaluated against changes in pH, electric conductivity (EC, cation exchange capacity (CEC, chlorophyll content, plant dry weight and plant height. The results showed that the addition of K+ and NH4+ affected pH, CEC, K+, NH4+, and water content of the buffer. Application of humic acid-based buffer significantly decreased soil pH from > 7 to about 6.3, decreased soil EC to 0.9 mS / cm, and increased exchangeable Na from 0.40 to 0.56 me / 100g soil, Ca from 15.57 to 20.21 me/100 g soil, Mg from 1.76 to 6.52 me/100 g soil, and K from 0.05-0.51 me / 100g soil. Plant growth (plant height, chlorophyll content, leaf area, and stem weight at 35 days after planting increased with increasing dose of humic acid. The dose of 2.0g peat humic acid + NH4+ / 3 kg of soil or 30g peat humic acid + K+ / 3 kg of oil gave the best results of maize growth.

  1. Cadmium accumulation characteristics and removal potentials of high cadmium accumulating rice line grown in cadmium-contaminated soils.

    Science.gov (United States)

    Tang, Hao; Li, Tingxuan; Yu, Haiying; Zhang, Xizhou

    2016-08-01

    Phytoextraction is a promising technique to remove cadmium (Cd) from contaminated soils. In this research, the two different Cd accumulation rice lines of Lu527-8 (the high Cd accumulating rice line) and Lu527-4 (the normal rice line) were grown in soils with different Cd treatments (0, 5, 10, and 20 mg kg(-1) soil) to evaluate Cd accumulation characteristics and Cd removal potentials. When the concentration of Cd in soil increased, Lu527-8 showed less symptoms of phytotoxicity when compared to Lu527-4. Furthermore, Lu527-8 demonstrated greater shoot Cd accumulation (321.17-964.95 mg plant(-1)) than Lu527-4 (50.37-201.66 μg plant(-1)) at the jointing and filling stages. The soil available Cd content of Lu527-8 significantly decreased by 26.92-38.97 and 27.77-63.44 % at the jointing and filling stages, respectively. Meanwhile, the total Cd content in soil also reduced by 11.64-46.75 and 21.41-54.11 % at jointing and filling stages, respectively. When the Cd concentration in soil was 20 mg kg(-1), the Cd extraction rate in shoots of Lu527-8 reached 2.12 and 2.85 % which increased 10.60 and 6.48 times compared with that of Lu527-4 at the jointing and filling stages, respectively. In conclusion, this study demonstrates that Lu527-8 shows great abilities of Cd accumulation and Cd removal potential from contaminated soils with different Cd treatments and it is a promising species for phytoextraction of Cd-contaminated soils.

  2. The Differential Mortality of Undesired Infants in Sub-Saharan Africa.

    Science.gov (United States)

    Flatø, Martin

    2018-02-01

    With high rates of infant mortality in sub-Saharan Africa, investments in infant health are subject to tough prioritizations within the household, in which maternal preferences may play a part. How these preferences will affect infant mortality as African women have ever-lower fertility is still uncertain, as increased female empowerment and increased difficulty in achieving a desired gender composition within a smaller family pull in potentially different directions. I study how being born at a parity or of a gender undesired by the mother relates to infant mortality in sub-Saharan Africa and how such differential mortality varies between women at different stages of the demographic transition. Using data from 79 Demographic and Health Surveys, I find that a child being undesired according to the mother is associated with a differential mortality that is not due to constant maternal factors, family composition, or factors that are correlated with maternal preferences and vary continuously across siblings. As a share of overall infant mortality, the excess mortality of undesired children amounts to 3.3 % of male and 4 % of female infant mortality. Undesiredness can explain a larger share of infant mortality among mothers with lower fertility desires and a larger share of female than male infant mortality for children of women who desire 1-3 children. Undesired gender composition is more important for infant mortality than undesired childbearing and may also lead couples to increase family size beyond the maternal desire, in which case infants of the surplus gender are particularly vulnerable.

  3. Humification degree and its relationship with some soil physical characteristics on robusta coffee (Coffea canephora plantation

    Directory of Open Access Journals (Sweden)

    M.J.N.F.I.A. Putra

    2016-07-01

    Full Text Available Soil moisture stress in coffee plant impacts on the productivity of coffee fruit at PT. Perkebunan Nusantara XII, it is because the low ability of the soil to store water. The ability of the soil to store water can be increased by increasing the organic matter content of soil, especially humic substances. Soil organic matter plays an important role in the improvement of soil physical properties, especially the availability of soil moisture for plants. The purpose of this study was to analyze several humification parameters at four age of plantations plots of coffee and its relation to the water distribution potensial on Inceptisol PT. Perkebunan Nusantara XII Malang district. The research was conducted at PT. Perkebunan Nusantara XII were taken soil samples from 8, 28, 40, and 80 years old robusta coffee plots at 0-30 cm and 30-60 cm soil depth. The results showed that the increasing the age of the coffee plantations significantly increased the input of organic matter in the soil, with indicators of increased litter on soil surface, increased levels of soil C-organic and N-total, humic acid and soil pH. Increasing age of coffee plantations until 80 years did not affect to the value of humification parameters (C/N ratio, HA/FA ratio, E4/E6 ratio, and the humification rate (HR. The age of coffee plantations affected the total acidity, carboxylic groups and phenolic OH, where the values tended to decrease with the older of coffee plantations in the 0-30 cm of soil layers and increased in 30-60 cm. Increasing age of coffee plantations improved the total pores and available water content in the 0-30 cm of soil layer.

  4. Characteristics of Soil and Organic Carbon Loss Induced by Water Erosion on the Loess Plateau in China.

    Science.gov (United States)

    Li, Zhongwu; Nie, Xiaodong; Chang, Xiaofeng; Liu, Lin; Sun, Liying

    2016-01-01

    Soil erosion has been a common environmental problem in the Loess Plateau in China. This study aims to better understand the losses of soil organic carbon (SOC) induced by water erosion. Laboratory-simulated rainfall experiments were conducted to investigate the characteristics of SOC loss induced by water erosion. The applied treatments included two rainfall intensities (90 and 120 mm h-1), four slope gradients (10°, 15°, 20°, and 25°), and two typical soil types- silty clay loam and silty loam. Results showed that the sediment OC enrichment ratios (ERoc) in all the events were relative stable with values ranged from 0.85 to1.21 and 0.64 to 1.52 and mean values of 0.98 and 1.01 for silty clay loam and silty loam, respectively. Similar to the ERoc, the proportions of different sized particles in sediment showed tiny variations during erosion processes. No significant correlation was observed between ERoc values and the proportions of sediment particles. Slope, rainfall intensity and soil type almost had no impact on ERoc. These results indicate that the transportation of SOC during erosion processes was nonselective. While the mean SOC loss rates for the events of silty clay loam and silty loam were 0.30 and 0.08 g m-2 min-1, respectively. Greater differences in SOC loss rates were found in events among different soil types. Meanwhile, significant correlations between SOC loss and soil loss for all the events were observed. These results indicated that the amount of SOC loss was influenced primarily by soil loss and the SOC content of the original soil. Erosion pattern and original SOC content are two main factors by which different soils can influence SOC loss. It seems that soil type has a greater impact on SOC loss than rainfall characteristics on the Loess Plateau of China. However, more kinds of soils should be further studied due to the special formation processes in the Loess Plateau.

  5. Characteristics of Soil and Organic Carbon Loss Induced by Water Erosion on the Loess Plateau in China

    Science.gov (United States)

    Li, Zhongwu; Nie, Xiaodong; Chang, Xiaofeng; Liu, Lin; Sun, Liying

    2016-01-01

    Soil erosion has been a common environmental problem in the Loess Plateau in China. This study aims to better understand the losses of soil organic carbon (SOC) induced by water erosion. Laboratory-simulated rainfall experiments were conducted to investigate the characteristics of SOC loss induced by water erosion. The applied treatments included two rainfall intensities (90 and 120 mm h-1), four slope gradients (10°, 15°, 20°, and 25°), and two typical soil types- silty clay loam and silty loam. Results showed that the sediment OC enrichment ratios (ERoc) in all the events were relative stable with values ranged from 0.85 to1.21 and 0.64 to 1.52 and mean values of 0.98 and 1.01 for silty clay loam and silty loam, respectively. Similar to the ERoc, the proportions of different sized particles in sediment showed tiny variations during erosion processes. No significant correlation was observed between ERoc values and the proportions of sediment particles. Slope, rainfall intensity and soil type almost had no impact on ERoc. These results indicate that the transportation of SOC during erosion processes was nonselective. While the mean SOC loss rates for the events of silty clay loam and silty loam were 0.30 and 0.08 g m-2 min-1, respectively. Greater differences in SOC loss rates were found in events among different soil types. Meanwhile, significant correlations between SOC loss and soil loss for all the events were observed. These results indicated that the amount of SOC loss was influenced primarily by soil loss and the SOC content of the original soil. Erosion pattern and original SOC content are two main factors by which different soils can influence SOC loss. It seems that soil type has a greater impact on SOC loss than rainfall characteristics on the Loess Plateau of China. However, more kinds of soils should be further studied due to the special formation processes in the Loess Plateau. PMID:27124482

  6. Manure-amended soil characteristics affecting the survival of E. coli O157:h7 in 36 Dutch soils

    NARCIS (Netherlands)

    Franz, E.; Semenov, A.V.; Termorshuizen, A.J.; Vos, de O.J.; Bokhorst, J.G.; Bruggen, van A.H.C.

    2008-01-01

    The recent increase in foodborne disease associated with the consumption of fresh vegetables stresses the importance of the development of intervention strategies that minimize the risk of preharvest contamination. To identify risk factors for Escherichia coli O157:H7 persistence in soil, we studied

  7. Scenario Studies on Effects of Soil Infiltration Rates, Land Slope, and Furrow Irrigation Characteristics on Furrow Irrigation-Induced Erosion.

    Science.gov (United States)

    Dibal, Jibrin M; Ramalan, A A; Mudiare, O J; Igbadun, H E

    2014-01-01

    Furrow irrigation proceeds under several soil-water-furrow hydraulics interaction dynamics. The soil erosion consequences from such interactions in furrow irrigation in Samaru had remained uncertain. A furrow irrigation-induced erosion (FIIE) model was used to simulate the potential severity of soil erosion in irrigated furrows due to interactive effects of infiltration rates, land slope, and some furrow irrigation characteristics under different scenarios. The furrow irrigation characteristics considered were furrow lengths, widths, and stream sizes. The model itself was developed using the dimensional analysis approach. The scenarios studied were the interactive effects of furrow lengths, furrow widths, and slopes steepness; infiltration rates and furrow lengths; and stream sizes, furrow lengths, and slopes steepness on potential furrow irrigation-induced erosion, respectively. The severity of FIIE was found to relate somewhat linearly with slope and stream size, and inversely with furrow lengths and furrow width. The worst soil erosion (378.05 t/ha/yr) was found as a result of the interactive effects of 0.65 m furrow width, 50 m furrow length, and 0.25% slope steepness; and the least soil erosion (0.013 t/ha/yr) was induced by the combined effects of 0.5 l/s, 200 m furrow length, and 0.05% slope steepness. Evidently considering longer furrows in furrow irrigation designs would be a better alternative of averting excessive FIIE.

  8. Greenhouse gas emissions and plant characteristics from soil cultivated with sunflower (Helianthus annuus L.) and amended with organic or inorganic fertilizers

    International Nuclear Information System (INIS)

    López-Valdez, F.; Fernández-Luqueño, F.; Luna-Suárez, S.; Dendooven, L.

    2011-01-01

    Agricultural application of wastewater sludge has become the most widespread method of disposal, but the environmental effects on soil, air, and crops must be considered. The effect of wastewater sludge or urea on sunflower's (Helianthus annuus L.) growth and yield, the soil properties, and the resulting CO 2 and N 2 O emissions are still unknown. The objectives of this study were to investigate: i) the effect on soil properties of organic or inorganic fertilizer added to agricultural soil cultivated with sunflower, ii) how urea or wastewater sludge increases CO 2 and N 2 O emissions from agricultural soil over short time periods, and iii) the effect on plant characteristics and yield of urea or wastewater sludge added to agricultural soil cultivated with sunflower. The sunflower was fertilized with wastewater sludge or urea or grown in unamended soil under greenhouse conditions while plant and soil characteristics, yield, and greenhouse gas emissions were monitored. Sludge and urea modified some soil characteristics at the onset of the experiment and during the first two months but not thereafter. Some plant characteristics were improved by sludge. Urea and sludge treatments increased the yield at similar rates, while sludge-amended soil significantly increased N 2 O emissions but not CO 2 emissions compared to the other amended or unamended soils. This implies that wastewater sludge increased the biomass and/or the yield; however, from a holistic point of view, using wastewater sludge as fertilizer should be viewed with concern.

  9. Investigations of the sorption characteristics of radiosilver on some natural and artificial soil particles

    Energy Technology Data Exchange (ETDEWEB)

    Szabo, Gyula; Guczi, Judit [`FJC` National Research Institute for Radiobiology and Radiohygiene, Budapest (Hungary); Valyon, Jozef [Central Research Institute for Chemistry, Hungarian Academy of Sciences, Budapest (Hungary); Bulman, Robert A. [National Radiological Protection Board, Chilton Didcot, England (United Kingdom)

    1995-09-05

    The likely distribution of {sup 110m}Ag(I), a radionuclide that may be produced in nuclear power stations and which has been known to contaminate the environment, between the components of particles of soil has been investigated by measuring its uptake from solutions of sodium nitrate, sodium EDTA and sodium citrate onto particles of chernozem soil and particles formed to simulate soils. The artificial soil particles were formed from: (1) silicas coated with manganese oxide, ferric oxide and hydrated ferric oxide, (2) silicas bearing chemically bound humic and fulvic acids and (3) alumina bearing anionically associated humic acid. These investigations have established that uptake of {sup 110m}Ag(I) by the humate coatings of soil particles will predominate under a wide range of pH. In the absence of humate coatings on the soil particles the radionuclide will be bound by the Fe/Mn oxide fractions of soils.

  10. Investigations of the sorption characteristics of radiosilver on some natural and artificial soil particles

    International Nuclear Information System (INIS)

    Szabo, Gyula; Guczi, Judit; Valyon, Jozef; Bulman, Robert A.

    1995-01-01

    The likely distribution of 110m Ag(I), a radionuclide that may be produced in nuclear power stations and which has been known to contaminate the environment, between the components of particles of soil has been investigated by measuring its uptake from solutions of sodium nitrate, sodium EDTA and sodium citrate onto particles of chernozem soil and particles formed to simulate soils. The artificial soil particles were formed from: (1) silicas coated with manganese oxide, ferric oxide and hydrated ferric oxide, (2) silicas bearing chemically bound humic and fulvic acids and (3) alumina bearing anionically associated humic acid. These investigations have established that uptake of 110m Ag(I) by the humate coatings of soil particles will predominate under a wide range of pH. In the absence of humate coatings on the soil particles the radionuclide will be bound by the Fe/Mn oxide fractions of soils

  11. Laboratory test investigations on soil water characteristic curve and air permeability of municipal solid waste.

    Science.gov (United States)

    Shi, Jianyong; Wu, Xun; Ai, Yingbo; Zhang, Zhen

    2018-04-01

    The air permeability coefficient has a high correlation with the water content of municipal solid waste. In this study, continuous drying methodology using a tension meter was employed to construct the soil water characteristic curve of municipal solid waste (M-SWCC). The municipal solid waste air permeability test was conducted by a newly designed apparatus. The measured M-SWCC was well reproduced by the van Genuchten (V-G) model and was used to predict the parameters of typical points in M-SWCC, including saturated water content, field capacity, residual water content and water content at the inflection point. It was found that the M-SWCC was significantly influenced by void ratio. The final evaporation and test period of M-SWCC increase with the increase in void ratio of municipal solid waste. The evolution of air permeability coefficient with water content of municipal solid waste depicted three distinct characteristic stages. It was observed that the water contents that corresponded to the two cut-off points of the three stages were residual water content and water content at the inflection point, respectively. The air permeability coefficient of municipal solid waste decreased with the increase of the water content from zero to the residual water content. The air permeability coefficient was almost invariable when the water content increased from residual water content to the water content at the inflection point. When the water content of municipal solid waste exceeded the water content at the inflection point, the air permeability coefficient sharply decreased with the increase of water content.

  12. Impact of a low severity fire on soil organic carbon and nitrogen characteristics in Japanese cedar soil Yamagata Prefecture, Japan

    Science.gov (United States)

    Seidel, Felix

    2017-04-01

    Slash and burn practices are widely used around the globe with different degrees of success which are mostly related to the impact of fire on the soil properties. In Japan slash and burn practises, known as Yakihata, have a long history and are still used in Yamagata Prefecture today. The purpose of this study was to determine the impact of a low severity controlled fire on Japanese cedar (Cryptomeria japonica) forest soil (Cambisol) which is the dominant species among plantations in Japan. We measured organic carbon and nitrogen content as well as changes in carbon (δ13C) and nitrogen (δ15N) stable isotope composition in a steep west facing slope under heavy precipitation ( 2600 mm/a) and heavy snowfall ( 3-4 m/a). The results show that Ctotal and Ntotal values as well as the isotopes ratios of C and N change with decreasing elevation in the forest as well as in the burned site being consistent with leaching and erosion. The accumulation of Ctotal and Ntotal at the bottom of the slopes was remarkably higher at the slash and burned site than in the control forest site. After slash and burn δ15N isotopes in the slope in general became significantly lighter than in the control forest while the δ13C did not show any significant difference between the two sites except at the bottom of the slopes where δ13C was heavier in the forest. The reason for these changes in nitrogen and carbon isotopes appears to be related to the physical changes in soil horizon sequence of the original forest soil layer. Keywords: high precipitation, Japanese cedar forest soil, low severity fire, stable isotopes, steep slopes

  13. Phosphorus Characteristics with Controlled Nitrogen in Fertile Soils in Protected Vegetable Field

    Directory of Open Access Journals (Sweden)

    WANG Heng

    2014-06-01

    Full Text Available There is an unreasonable phenomenon of fertilization in vegetable facility cultivation, with the serious imbalance of soil nutrient. In purpose of understanding the absorption characteristics of phosphorus from nitrogen-rich soil, a long-term nitrogen-controlled experiment was carried from the year 2004 to 2007, and a split plot experiment of leaching was carried in winter-spring season of 2007. The results showed that the content of phosphorus varied with different nitrogen control. The TP was decreased with nitrogen supply of none(NN 、organic manure(MN 、organic manure and straw(MN+S, and the decreased range was NN>MN>MN+S, meanwhile the increase range of TP was traditional-nitrogen(CN >traditional-nitrogen+straw(CN+S >optimized-nitrogen+straw(SN+S >optimized-nitrogen(SN. The available P with CN and CN+S reached to 213.7 mg· kg -1 、225.4 mg·kg -1, which increased by 17.1 percent and 23.5 percent, which declared the phosphorus was accumulated; The available P with other nitrogen controlled decreased with the range of NN>MN>MN+S>SN+S>SN跃CN>CN+S, which showed that the supply reduction of nitrogen could slowdown the phosphorus accumulated and promote the utilization ratio of phosphorus. The organophosphorus was increased except NN, with obvious increase with CN、CN+S(308.4 mg·kg -1 、331.4 mg·kg -1 by 28.5 percent and 38.2 percent. The absorption coefficient of phosphorus with SN+S(P 2 O 5,mg· 100 g -1 reached to 1 571, increased by 143.6 percent; Otherwise the absorption coefficient of phosphorus with CN、CN+S showed negative growth, the CN dipped to 416(P 2 O 5,mg·100 g -1 by 35.5 percent. Adding wheat straw could greatly improved the capacity of absorption of phosphorus and slow down the accumulation of available phosphorus to some extent. The concentrations of total phosphorus in the filtrate with SN+S were less than SN, contrary to the concentration of organophosphorus, thus the straw returning had a certain effect on

  14. Using grain-size characteristics to model soil water content: Application to dose-rate calculation for luminescence dating

    International Nuclear Information System (INIS)

    Nelson, Michelle S.; Rittenour, Tammy M.

    2015-01-01

    Soil moisture is an important factor for dose-rate determination in luminescence and other dating methods as soil water content impacts sediment bulk density, alters rates of chemical reactions and attenuates effective exposure to nuclear radiation from the surrounding sediments and incoming cosmic rays. Given its importance in dose-rate calculation, methods for measuring and modeling soil water content are discussed, with special focus on semi-arid environments and other situations where modern in situ values are unlikely to be representative of mean soil moisture conditions. We present an alternative method for calculating sediment water content based on grain-size characteristics using the freely available Rosetta Lite v.1.1 software. Modeled outputs include saturation, residual and other water retention curve (WRC) parameters. WRCs were generated from model outputs using the van Genuchten (1980) equation, and mean annual water state was determined using soil moisture regime maps and classifications. Dose-rate values using modeled outputs and laboratory-measured in situ and saturation water content are compared in a test case using Holocene alluvial sediments from Kanab Creek in southern Utah, USA. Best practices for how to estimate mean annual water state for different soil moisture regimes and past soil moisture content in situations where in situ values are not representative of the burial history are discussed. - Highlights: • Using grain size characteristics to generate water retention curves. • Saturation water content was estimated using laboratory and computer modeling. • In situ water content is compared with the model outputs. • Dose-rate variability with new water content estimates is evaluated.

  15. Stochastic analysis of uncertain thermal characteristic of foundation soils surrounding the crude oil pipeline in permafrost regions

    International Nuclear Information System (INIS)

    Wang, Tao; Zhou, Guoqing; Wang, Jianzhou; Zhao, Xiaodong

    2016-01-01

    Highlights: • The influence of stochastic properties and conditions on permafrost foundation was investigated. • A stochastic analysis for the uncertain thermal characteristic of crude oil pipe is presented. • The mean temperature and standard deviation of foundation soils are obtained and analyzed. • Average standard deviation and maximum standard deviation of foundation soils increase with time. - Abstract: For foundation soils surrounding the crude oil pipeline in permafrost regions, the soil properties and the upper boundary conditions are stochastic because of complex geological processes and changeable atmospheric environment. The conventional finite element analysis of thermal characteristics for crude oil pipeline is always deterministic, rather than taking stochastic parameters and conditions into account. This study investigated the stochastic influence of an underground crude oil pipeline on the thermal stability of the permafrost foundation on the basis of a stochastic analysis model and the stochastic finite element method. A stochastic finite element program is compiled by Matrix Laboratory (MATLAB) software, and the random temperature fields of foundation soils surrounding a crude oil pipeline in a permafrost region are obtained and analyzed by Neumann stochastic finite element method (NSFEM). The results provide a new way to predict the thermal effects of the crude oil pipeline in permafrost regions, and it shows that the standard deviations in temperature increase with time when considering the stochastic effect of soil properties and boundary conditions, which imply that the results of conventional deterministic analysis may be far from the true value, even if in different seasons. It can improve our understanding of the random temperature field of foundation soils surrounding the crude oil pipeline and provide a theoretical basis for actual engineering design in permafrost regions.

  16. Desirable and undesirable future thoughts call for different scene construction processes.

    Science.gov (United States)

    de Vito, S; Neroni, M A; Gamboz, N; Della Sala, S; Brandimonte, M A

    2015-01-01

    Despite the growing interest in the ability of foreseeing (episodic future thinking), it is still unclear how healthy people construct possible future scenarios. We suggest that different future thoughts require different processes of scene construction. Thirty-five participants were asked to imagine desirable and less desirable future events. Imagining desirable events increased the ease of scene construction, the frequency of life scripts, the number of internal details, and the clarity of sensorial and spatial temporal information. The initial description of general personal knowledge lasted longer in undesirable than in desirable anticipations. Finally, participants were more prone to explicitly indicate autobiographical memory as the main source of their simulations of undesirable episodes, whereas they equally related the simulations of desirable events to autobiographical events or semantic knowledge. These findings show that desirable and undesirable scenarios call for different mechanisms of scene construction. The present study emphasizes that future thinking cannot be considered as a monolithic entity.

  17. Ranking of bank branches with undesirable and fuzzy data: A DEA-based approach

    Directory of Open Access Journals (Sweden)

    Sohrab Kordrostami

    2016-07-01

    Full Text Available Banks are one of the most important financial sectors in order to the economic development of each country. Certainly, efficiency scores and ranks of banks are significant and effective aspects towards future planning. Sometimes the performance of banks must be measured in the presence of undesirable and vague factors. For these reasons in the current paper a procedure based on data envelopment analysis (DEA is introduced for evaluating the efficiency and complete ranking of decision making units (DMUs where undesirable and fuzzy measures exist. To illustrate, in the presence of undesirable and fuzzy measures, DMUs are evaluated by using a fuzzy expected value approach and DMUs with similar efficiency scores are ranked by using constraints and the Maximal Balance Index based on the optimal shadow prices. Afterwards, the efficiency scores of 25 branches of an Iranian commercial bank are evaluated using the proposed method. Also, a complete ranking of bank branches is presented to discriminate branches.

  18. Simultaneous removal and degradation characteristics of sulfonamide, tetracycline, and quinolone antibiotics by laccase-mediated oxidation coupled with soil adsorption.

    Science.gov (United States)

    Ding, Huijun; Wu, Yixiao; Zou, Binchun; Lou, Qian; Zhang, Weihao; Zhong, Jiayou; Lu, Lei; Dai, Guofei

    2016-04-15

    The uses of laccase in the degradation and removal of antibiotics have recently been reported because of the high efficiency and environmental friendliness of laccase. However, these removal studies mostly refer to a limited number of antibiotics. In this study, soil adsorption was introduced into the laccase-oxidation system to assist the simultaneous removal of 14 kinds of sulfonamide, tetracycline, and quinolone antibiotics, which differed in structures and chemical properties. The complementary effects of laccase-mediated oxidation and soil adsorption enabled the simultaneous removal. Removal characteristics were determined by a comprehensive consideration of the separate optimum conditions for laccase oxidation and soil adsorption removal experiments. With concentrations of laccase, syringaldehyde (SA), and soil of 0.5mg/mL, 0.5mmol/L, and 50g/L, respectively, and at pH 6 and 25°C, the removal rates of each antibiotic exceeded 70% in 15min and were close to 100% in 180min. Sulfonamide antibiotics (SAs) were removed mainly by laccase oxidation and quinolone antibiotics (QUs) mainly by soil adsorption. Tetracycline antibiotics (TCs) were removed by both treatments in the coupled system, but laccase oxidation dominated. Electrostatic adsorption was speculated to be one of the adsorption mechanisms in soil adsorption with QUs and TCs. Copyright © 2015 Elsevier B.V. All rights reserved.

  19. [Spatial distribution characteristics of organic carbon in the soil-plant systems in the Yellow River estuary tidal flat wetland].

    Science.gov (United States)

    Dong, Hong-Fang; Yu, Jun-Bao; Sun, Zhi-Gao; Mu, Xiao-Jie; Chen, Xiao-Bing; Mao, Pei-Li; Wu, Chun-Fa; Guan, Bo

    2010-06-01

    Well-understand the organic carbon status in the Yellow River delta is the most important for studying the biogeochemical processes of the muddy-sandy coastal wetland and ecological restoration. The spatial distribution characteristics and its impact factors of organic carbon in the plant-soil systems of new-born tidal flat wetland in the Yellow River estuary were studied. The results showed that the difference of plant organic carbon content in different plant communities were not obvious, however significant difference of the plant organic carbon density was observed. Moreover, the M-shaped spatial distribution of the plant organic carbon density, which was similar to the plant biomass, was found in the study. The organic carbon contents in top soils were varied from 0.75 to 8.35 g x kg(-1), which was much lower than that in the typical freshwater marsh wetlands ecosystem. The spatial distribution trend of soil organic carbon density was similar to the soil organic carbon. The correlation analysis showed that soil organic carbon density was negatively correlated with pH, and positively correlated with TN, C/N and salinity. However, the correlations of plant organic carbon density with the soil organic carbon density, TN, C/N, pH and salinity were not significant.

  20. [Characteristics of soil moisture variation in different land use types in the hilly region of the Loess Plateau, China].

    Science.gov (United States)

    Tang, Min; Zhao, Xi Ning; Gao, Xiao Dong; Zhang, Chao; Wu, Pu Te

    2018-03-01

    Soil water availability is a key factor restricting the ecological construction and sustainable land use in the loess hilly region. It is of great theoretical and practical significance to understand the soil moisture status of different land use types for the vegetation restoration and the effective utilization of land resources in this area. In this study, EC-5 soil moisture sensors were used to continuously monitor the soil moisture content in the 0-160 cm soil profile in the slope cropland, terraced fields, jujube orchard, and grassland during the growing season (from May to October) in the Yuanzegou catchment on the Loess Plateau, to investigate soil moisture dynamics in these four typical land use types. The results showed that there were differences in seasonal variation, water storage characteristics, and vertical distribution of soil moisture under different land use types in both the normal precipitation (2014) and dry (2015) years. The terraced fields showed good water retention capacity in the dry year, with the average soil moisture content of 0-60 cm soil layer in the growing season being 2.6%, 4.2%, and 1.8% higher than that of the slope cropland, jujube orchard, and grassland (all Pmoisture content of 0-60 cm soil layer in jujube orchard in the growing season was 2.9%, 3.8%, and 4.5% lower than that of slope cropland, terraced fields, and grassland, respectively (all Pmoisture in the surface layer (0-20 cm) and soil moisture in the middle layer (20-100 cm) under different land use types was large, and the trend for the similarity degree of soil moisture variation followed terraced fields > grassland > slope cropland > jujube orchard. The slope cropland in this area could be transformed into terraced fields to improve the utilization of precipitation and promote the construction of ecological agriculture. Aiming at resolving the severe water shortage in the rain-fed jujube orchard for the sustainable development of jujube orchard in the loess hilly

  1. Land use and Hydrological Characteristics of Volcanic Urban Soils for Flood Susceptibility Modeling, Ciudad de Colima (Mexico)

    Science.gov (United States)

    Perez Gonzalez, M. L.; Capra, L.; Borselli, L.; Ortiz, A.

    2015-12-01

    soil characteristics using the Pedotransfer Functions. The hydraulic conductivity measured in situ using a Drip-Infiltrometer device provide Ks values of 4.5, 2.4 and 5 cm/h for urban, agricultural and natural soils respectively. The information described is integrated on a GIS data base and it is an input for the Flood Susceptibility Model of Colima's metropolitan area on progress.

  2. [Characteristics of mercury pollution in soil and atmosphere in Songhua River upstream Jia-pi-gou gold mining area].

    Science.gov (United States)

    Zhang, Gang; Wang, Ning; Wang, Yuan; Liu, Te; Ai, Jian-Chao

    2012-09-01

    In the studied area of Jia-pi-gou at the upstream area of Songhua River, algamation process has been applied as a dominant method to extract gold for more than one hundred and eighty years, resulting in severe mercury environmental pollution. The total mercury contents in the atmosphere and soil have been determined by mercury analyzer (Zeeman RA915+) and cold atomic absorption spectrophotometry (GB/T 17136-1997), respectively. To study the pollution characteristics of mercury in the soil and atmosphere, the mercury flux at the interface between the soil and the atmosphere of 4 sampling sites Lao-jin-chang, Er-dao-gou, Er-dao-cha and community of Jia-pi-gou have been determined with the method of dynamic flux chamber. Furthermore, linear regression analyses on the total mercury contents between soil and atmosphere have been carried out and the correlation coefficient of mercury exchange flux between soil and atmosphere and meteorological factors has been studied. The results are as follows: (1) The mean value of mercury content in the atmosphere is (71.08 +/- 38.22) ng x m(-3). (2) The mean value of mercury content in the soil is (0.913 1 +/- 0.040 8) mg x kg(-1); it shows remarkably positive correlation between the mercury contents in soil and in the atmosphere. (3) The mercury exchange flux between soil and atmosphere in different locations are Lao-jin-chang [(129.13 +/- 496.07) ng (m2 x h)(-1)], Er-dao-gou [(98.64 +/- 43.96) ng x (m2 x h)(-1)], Er-dao-cha [(23.17 +/- 171.23) ng x (m2 x h)(-1)], and community of Jia-pi-gou [(7.12 +/- 46.33) ng x (m2 x h)(-1)]. (4) Solar radiation is the major influential factor in the mercury exchange flux between the soil and atmosphere in Lao-jin-chang, Er-dao-cha and community of Jia-pi-gou. Solar radiation, air temperature and soil temperature jointly influence the process of the mercury exchange flux between the soil and atmosphere in Er-dao-gou. Under the disturbance of terrain, three noticeably distinctive trend features

  3. Risk management of undesirable substances in feed following updated risk assessments

    International Nuclear Information System (INIS)

    Verstraete, Frans

    2013-01-01

    Directive 2002/32/EC of 7 May 2002 of the European Parliament and of the Council on undesirable substances in animal feed is the framework for the EU action on undesirable substances in feed. This framework Directive provides: ⁎that products intended for animal feed may enter for use in the Union from third countries, be put into circulation and/or used in the Union only if they are sound, genuine and of merchantable quality and therefore when correctly used do not represent any danger to human health, animal health or to the environment or could adversely affect livestock production. ⁎that in order to protect animal and public health and the environment, maximum levels for specific undesirable substances shall be established where necessary. ⁎for mandatory consultation of a scientific body (EFSA) for all provisions which may have an effect upon public health or animal health or on the environment. ⁎that products intended for animal feed containing levels of an undesirable substance that exceed the established maximum level may not be mixed for dilution purposes with the same, or other, products intended for animal feed and may not be used for the production of compound feed. Based on the provisions and principles laid down in this framework Directive, maximum levels for a whole range of undesirable substances have been established at EU level. During the discussions in view of the adoption of Directive 2002/32/EC, the European Commission made the commitment to review all existing provisions on undesirable substances on the basis of updated scientific risk assessments. Following requests of the European Commission, the Panel on Contaminants in the Food Chain (CONTAM) from the European Food Safety Authority (EFSA) has completed a series of 30 risk assessments undertaken over the last 5 years on undesirable substances in animal feed reviewing the possible risks for animal and human health due to the presence of these substances in animal feed. EU legislation

  4. Effects of simulated acid rain on microbial characteristics in a lateritic red soil.

    Science.gov (United States)

    Xu, Hua-qin; Zhang, Jia-en; Ouyang, Ying; Lin, Ling; Quan, Guo-ming; Zhao, Ben-liang; Yu, Jia-yu

    2015-11-01

    A laboratory experiment was performed to examine the impact of simulated acid rain (SAR) on nutrient leaching, microbial biomass, and microbial activities in a lateritic red soil in South China. The soil column leaching experiment was conducted over a 60-day period with the following six SAR pH treatments (levels): 2.5, 3.0, 3.5, 4.0, 4.5, and 5.0 and one control treatment (pH = 7). Compared with the control treatment, the concentrations of soil organic matter, total nitrogen, total phosphorus, total potassium, soil microbial biomass carbon (MBC), soil microbial biomass nitrogen (MBN), and average well color density (AWCD) in the Ecoplates were all significantly decreased by leaching with SAR at different pH levels. The decrease in MBC and MBN indicated that acid rain reduced the soil microbial population, while the decrease in AWCD revealed that acid rain had a negative effect on soil bacterial metabolic function. Soil basal respiration increased gradually from pH 4.0 to 7.0 but decreased dramatically from pH 2.5 to 3.0. The decrease in soil nutrient was the major reason for the change of soil microbial functions. A principal component analysis showed that the major carbon sources used by the bacteria were carbohydrates and carboxylic acids.

  5. Adsorption and desorption characteristic of benzimidazole based fungicide carbendazim in pakistani soils

    International Nuclear Information System (INIS)

    Ahmad, K.S.; Rashid, N.; Tazaiyen, S.; Nazar, M.F.

    2013-01-01

    A versatile cost-effective Benzimidazole based fungicide, Carbendazim (methyl 1H-benzimidazole-2 carboxylate ) has been utilized to investigate its sorption-desorption behaviour on physicochemical properties of geographical soils, ranging from hilly to desert areas of Pakistan, via batch equilibrium method. The data obtained in all tests showed that adsorption co-efficient isotherm for Carbendazim in four tested soil were well fitted the freundlich equation. Distribution co-efficient (K d ) parameters are low (3.59 to 11.60 ml micro g/sup -1/) indicating low adsorption. It was observed that Carbendazim showed a relatively greater degree of adsorption on soil samples (Soil 4) that were collected from northern hilly areas Ayubia, Khyber Pakhton khaw (KPK) (Silt loam) i.e.11.60 ml mu g/sup -1/ and least adsorption on sandy Soil of Multan Punjab(Soil 2). While other two soils 1 were collected from Murree region, a boarder of Punjab and KPK mountain area and Soil 3 from Tarnol, Islamabad. Desorption studies reveal that the adsorbed fungicide is firmly retained by soil particles and their adsorption are almost irreversible. The results indicate that soil organic matter (SOM) and appropriate pH also play key role in sorption capacity. (author)

  6. [Effects of crop rotation and bio-organic manure on soil microbial characteristics of Chrysanthemum cropping system].

    Science.gov (United States)

    Xiao, Xin; Zhu, Wei; Du, Chao; Shi, Ya-dong; Wang, Jian-fei

    2015-06-01

    We conducted a field experiment to evaluate the effects of rotation system and bio-organic manure on soil microbial characteristics of Chrysanthemum cropping system. Taking Chrysanthemum morifolium Ramat and wheat as experimental plants, treatments under Chrysanthemum continuous cropping system (M1), conventional Chrysanthemum-wheat rotation system (M2), and Chrysanthemum-wheat rotation system receiving bio-organic manure application of 200 kg · 667 m(-2) (M3) were designed. Soil chemical properties, soil microbial biomass carbon (MBC) and nitrogen (MBN), and the amounts of different types of soil microorganisms were determined. Results showed that compared with M1, treatments of M2 and M3 significantly increased soil pH, organic matter, available N, P, and K, MBC, MBN, and the amounts of bacteria, fungi and actinomycetes, but decreased the ratio of MBC/MBN, and the relative percentage of fungi in the total amount of microorganisms. Treatment of M3 had the highest contents of soil organic matter, available N, available P, available K, MBC, MBN, and the amounts of bacteria, fungi and actinomycetes, with the values being 15.62 g · kg(-1), 64.75 mg · kg(-1), 83.26 mg · kg(-1), 96.72 mg · kg(-1), 217.40 mg · kg(-1), 38.41 mg · kg(-1), 22.31 x 10(6) cfu · g(-1), 56.36 x 10(3) cfu · g(-1), 15.90 x 10(5) cfu · g(-1), respectively. We concluded that rational crop rotation and bio-organic manure application could weaken soil acidification, improve soil fertility and microbial community structure, increase the efficiency of nutrition supply, and have a positive effect on reducing the obstacles of continuous cropping.

  7. Soils

    International Nuclear Information System (INIS)

    Freudenschuss, A.; Huber, S.; Riss, A.; Schwarz, S.; Tulipan, M.

    2001-01-01

    For Austria there exists a comprehensive soil data collection, integrated in a GIS (geographical information system). The content values of pollutants (cadmium, mercury, lead, copper, mercury, radio-cesium) are given in geographical charts and in tables by regions and by type of soil (forests, agriculture, greenland, others) for the whole area of Austria. Erosion effects are studied for the Austrian region. Legal regulations and measures for an effective soil protection, reduction of soil degradation and sustainable development in Austria and the European Union are discussed. (a.n.)

  8. Characteristics of the soil in mountain beech communities on mountain Manjača

    Directory of Open Access Journals (Sweden)

    Eremija Saša

    2008-01-01

    Full Text Available The presented results of soil study, which will be used for defining the beech forest types of management unit 'Dubička Gora' on Mt. Manjača, are the basis for solving a series of current tasks of forestry profession. Relief and chemical nature of limestone are the main factors of the soil cover differentiation (Knežević, Košanin, 2004.. The results of physical and chemical soil properties are shown and its taxonomy is determined. Forest cover is represented by heterogeneous units-forest combinations. Four basic soil types are defined on the basis of detailed field and laboratory research: rendzina on dolomite, chernozem on limestone, brown soil on limestone, illimerised soil on limestone and dolomite.

  9. [Soil fertility characteristics under different land use patterns in depressions between karst hills].

    Science.gov (United States)

    Liu, Yan; Song, Tong-Qing; Cai, De-Suo; Zeng, Fu-Ping; Peng, Wan-Xia; Du, Hu

    2014-06-01

    Soil samples were collected from the depressions between karst hills by grid sampling method (5 m x 5 m), soil pH, soil organic carbon (SOC), total nitrogen (TN), total phosphorus (TP), total potassium (TK), available nitrogen (AN), available phosphorus (AP), and available potassium (AK) in surface layer (0-20 cm) under different land use patterns (burning, cutting, cutting plus root removal, enclosure, maize plantation, and pasture plantation) were measured, the main factors of influencing the soil fertility was identified by principal component analysis (PCA), and the relationships between soil nutrients and microorganisms were demonstrated by canonical correlation analysis (CCA). The results showed that the soil was slightly alkaline (pH 7.83-7.98), and the soil fertility differed under the different land use patterns, with 76.78-116.05 g x kg(-1) of SOC, 4.29-6.23 g x kg(-1) of TN, 1.15-1.47 g x kg(-1) of TP, 3.59-6.05 g x kg(-1) of TK, 331.49-505.49 mg x kg(-1) of AN), 3.92-10.91 mg x kg(-1) of AP, and 136.28-198.10 mg x kg(-1) of AK. These soil indexes except pH showed moderate or strong variation. Different land use patterns had various impacts on soil fertility: Soil nutrients such as SOC, TN, TP, and AN were most significantly influenced by land use patterns in the depressions between karst hills; Followed by soil microorganisms, especially soil actinomycetes, and the effect decreased with the increasing gradient of human disturbance from enclosure, burning, cutting, cutting plus root removal, pasture plantation, and maize plantation. CCA elucidated that considerable interactions existed in soil TP with MBP (microbial biomass phosphorus), TK with MBC (microbial biomass carbon), TN with actinomycetes in the burned area, while TN and MBC in the cutting treatment, AP and MBN (microbial biomass nitrogen) in the treatment of cutting plus root removal, pH with MBC and fungus in the enclosure treatment, TN and TK with MBP in the maize plantation, pH with fungi

  10. Unique Rhizosphere Micro-characteristics Facilitate Phytoextraction of Multiple Metals in Soil by the Hyperaccumulating Plant Sedum alfredii.

    Science.gov (United States)

    Hou, Dandi; Wang, Kai; Liu, Ting; Wang, Haixin; Lin, Zhi; Qian, Jie; Lu, Lingli; Tian, Shengke

    2017-05-16

    Understanding the strategies that the roots of hyperaccumulating plants use to extract heavy metals from soils is important for optimizing phytoremediation. The rhizosphere characteristics of Sedum alfredii, a hyperaccumulator, were investigated 6 months after it had been planted in weathered field soils contaminated with 5.8 μg of Cd g -1 , 1985.1 μg of Zn g -1 , 667.5 μg of Pb g -1 , and 698.8 μg of Cu g -1 . In contrast with the non-hyperaccumulating ecotype (NHE), the hyperaccumulating ecotype (HE) of S. alfredii was more tolerant to the metals, and higher levels of Cd and Zn accumulated. The HE was characterized by a unique rhizosphere, including extensive root systems, a reduced soil pH, a higher metal bioavailability, and increased rhizomicrobial activity. The bioavailability of metals was significantly correlated with the HE's unique bacterial communities (P heavy metal phytoextraction.

  11. A New Two-Stage Approach to predicting the soil water characteristic from saturation to oven-dryness

    DEFF Research Database (Denmark)

    Karup Jensen, Dan; Tuller, Markus; de Jonge, Lis Wollesen

    2015-01-01

    The present study proposes a new two-step approach to prediction of the continuous soil water characteristic (SWC) from saturation to oven-dryness from a limited number of measured textural data, organic matter content and dry bulk density. The approach combines dry- and wet-region functions...... to pore size fractions and utilizes the capillary rise equation to predict water content and matric potential pairs. Twenty-one Arizona source soils with clay and organic carbon contents ranging from 0.01 to 0.52 kg kg−1 and 0 to 0.07 kg kg−1, respectively, were used for the model development. The SWCs...... were measured with Tempe cells, a WP4-T Dewpoint Potentiameter, and a water vapor sorption analyzer (VSA). The model was subsequently tested for eight soils from various agricultural fields in Denmark with clay contents ranging from 0.05 to 0.41 kg kg−1. Test results clearly revealed that the proposed...

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

    Science.gov (United States)

    Jalali, Mohsen

    2007-10-01

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

  13. Relationships between College Students' Credit Card Debt, Undesirable Academic Behaviors and Cognitions, and Academic Performance

    Science.gov (United States)

    Hogan, Eileen A.; Bryant, Sarah K.; Overymyer-Day, Leslie E.

    2013-01-01

    The acquisition of credit card debt by college students has long been a topic of concern. This study explores relationships among debt, undesirable academic behaviors and cognitions, and academic performance, through surveys of 338 students in a public university, replicating two past measures of credit card debt and creating new measures of…

  14. A survey on the presence of undesirable botanical substances in feed in the European Union

    NARCIS (Netherlands)

    Raamsdonk, van L.W.D.; Vancutsem, J.; Jorgensen, J.S.

    2009-01-01

    Directive 2002/32/EC of the European Parliament and of the Council of 7 May 2002 on undesirable substances in animal feed lists a range of substances from botanical origin (weed seeds) and additionally some chemical compounds directly originating from specific weeds. In order to examine the actual

  15. Array diagnostics, spatial resolution, and filtering of undesired radiation with the 3D reconstruction algorithm

    DEFF Research Database (Denmark)

    Cappellin, C.; Pivnenko, Sergey; Jørgensen, E.

    2013-01-01

    This paper focuses on three important features of the 3D reconstruction algorithm of DIATOOL: the identification of array elements improper functioning and failure, the obtainable spatial resolution of the reconstructed fields and currents, and the filtering of undesired radiation and scattering...

  16. Toxicities of TNT and RDX to Terrestrial Plants in Five Soils with Contrasting Characteristics

    Science.gov (United States)

    2013-07-01

    studies, corn, tomato , and lettuce died when exposed to 580 mg RDX/kg soil and 1720 mg TNT/kg soil (Price et al., 1997; Pennington and Brannon, 2002...conclusion of the test, and  The composite fresh- and dry-shoot masses (SFM and SDM, respectively) per replicate treatment (20 plants) at the conclusion

  17. Study on the adsorption-desorption characteristics of 14C-pirimicarb in soils

    International Nuclear Information System (INIS)

    Guo Jiangfeng; Sun Jinhe; Li Xingming

    1995-01-01

    14 C-pirimicarb was used to study its adsorption-desorption behavior in 8 kinds of soils. The results indicated that there were significant differences in its adsorption with different kinds of soil. The lowest adsorption percentage was only 13.16% and the highest one was 87.75%. The amount of adsorption in the same kind of soil increased with the concentration of pesticide, but concentration had little influence on the adsorption within the certain range of concentrations. Multiple linear regression equation was developed for prediction of adsorption and determination of the relative importance of the soil parameters. It was significant that the key factors, soil pH and clay content were negatively and positively correlated with the adsorption respectively. The adsorption equilibrium of pirimicarb in soils could be well described by both the Freundlich isotherm and the Langmuir isotherm. The adsorbed 14 C-pirimicarb could disrobe from soil and its desorption was also influenced by soil properties described by multiple linear regression equation

  18. Characteristics of soils and saprolite in Solid Waste Storage Area 6

    International Nuclear Information System (INIS)

    Ammons, J.T.; Phillips, D.H.; Timpson, M.E.

    1987-01-01

    Solid Waste Storage Area 6 (SWSA-6) is one of the disposal sites for solid low-level radioactive waste at Oak Ridge National Laboratory. Soils and saprolites from the site were characterized to provide base line information to initiate assessment for remedial actions and closure plans. Physical, chemical, mineralogical, and engineering analyses were conducted on soil and saprolite samples

  19. Ground-Water Levels and Soil Characteristics in a Forested Typic Glossaqualf

    Science.gov (United States)

    Peter L. Lorio

    1977-01-01

    The presence of impermeable layers can affect the development of a soil and its water regime. In a forested Typic Glossaqualf in southwest Louisiana, moisture, density, and piezometer measurements revealed an impermeable layer of soil between about 1.8 and 2.8 m below the surface. A high proportion of very fine sand and development of platy structure appeared related...

  20. Climate-related changes of soil characteristics affect bacterial community composition and function of high altitude and latitude lakes.

    Science.gov (United States)

    Rofner, Carina; Peter, Hannes; Catalán, Núria; Drewes, Fabian; Sommaruga, Ruben; Pérez, María Teresa

    2017-06-01

    Lakes at high altitude and latitude are typically unproductive ecosystems where external factors outweigh the relative importance of in-lake processes, making them ideal sentinels of climate change. Climate change is inducing upward vegetation shifts at high altitude and latitude regions that translate into changes in the pools of soil organic matter. Upon mobilization, this allochthonous organic matter may rapidly alter the composition and function of lake bacterial communities. Here, we experimentally simulate this potential climate-change effect by exposing bacterioplankton of two lakes located above the treeline, one in the Alps and one in the subarctic region, to soil organic matter from below and above the treeline. Changes in bacterial community composition, diversity and function were followed for 72 h. In the subarctic lake, soil organic matter from below the treeline reduced bulk and taxon-specific phosphorus uptake, indicating that bacterial phosphorus limitation was alleviated compared to organic matter from above the treeline. These effects were less pronounced in the alpine lake, suggesting that soil properties (phosphorus and dissolved organic carbon availability) and water temperature further shaped the magnitude of response. The rapid bacterial succession observed in both lakes indicates that certain taxa directly benefited from soil sources. Accordingly, the substrate uptake profiles of initially rare bacteria (copiotrophs) indicated that they are one of the main actors cycling soil-derived carbon and phosphorus. Our work suggests that climate-induced changes in soil characteristics affect bacterioplankton community structure and function, and in turn, the cycling of carbon and phosphorus in high altitude and latitude aquatic ecosystems. © 2016 The Authors. Global Change Biology Published by John Wiley & Sons Ltd.

  1. Mars 2001 Mission: Addressing Scientific Questions Regarding the Characteristics and Origin of Local Bedrock and Soil

    Science.gov (United States)

    Saunders, R. S.; Arvidson, R. E.; Weitz, C. M.; Marshall, J.; Squyres, S. W.; Christensen, P. R.; Meloy, T.; Smith, P.

    1999-09-01

    The Mars Surveyor Program 2001 Mission will carry instruments on the orbiter, lander and rover that will support synergistic observations and experiments to address important scientific questions regarding the local bedrock and soils. The martian surface is covered in varying degrees by fine materials less than a few mms in size. Viking and Pathfinder images of the surface indicate that soils at those sites are composed of fine particles. Wheel tracks from the Sojourner rover suggest that soil deposits are composed of particles 100 microns and soils are dominated by wom away through prolonged transport over the eons? Were they never generated to begin with? Or are they simply less easy to identify because do they not form distinctive geomorphic features such as dunes or uniform mantles that tend to assume superposition in the soil structure?

  2. Characteristics of soils developed from alluvium and their potential for cocoa plant development in East Kolaka Regency, Southeast Sulawesi

    Directory of Open Access Journals (Sweden)

    E. Yatno

    2016-04-01

    Full Text Available Cocoa is one of plantation commodities that is quite important for the national economy. Land management for the development of this plant should pay attention to the characteristics of the soil. Three soil profiles formed from alluvium parent material in East Kolaka Regency were investigated to determine the mineralogical, physical, and chemical soil properties, as well as the potential of the land for the development of cocoa plant. The results showed that the mineral composition of the sand fraction was dominated by quartz, while the clay mineral fraction was composed of kaolinite, hydrate halloysite, interstratified of illite-vermiculite and smectite. The soils were characterized by poor drainage, low bulk density (0.78 to 0.95 g / cm3, moderate available water pores (10-15%, slow to fast permeability (0.10 to 14.05 cm / h, silty clay loam to silty clay texture of top soil, acidic soil reaction (pH 4.62 to 5.47, high organic C content (3.86 to 4.60% in the top soil and very low organic C content (<0.65% in the lower layer, moderate to high available P (14-38 mg / kg in the A horizon and very low to moderate (1-18 mg / kg in horizon B, moderate to high P2O5 (30-71 mg / 100g in horizon A and extremely low (1-11 mg / 100g in horizon B, very low to moderate K2O (3-28 mg / 100g , moderate to high exchangeable Ca (9.32 to 13.92 cmolc / kg in the upper and lower (0.70 to 5.04 cmolc / kg in the bottom layer, high exchangeable Mg content (2.83 to 8.95 cmolc / kg, high soil CEC (34.18 to 38.28 cmolc / kg in the upper layer and low to moderate (7.87 to 20.39 cmolc / kg in the bottom layer, moderate to high base saturation (44-68%, and very low to moderate Al saturation (0-17%. At the family level, the soil was classified as Fluvaquentic Endoaquepts (EK 1 profile and Typic Endoaquepts (EK 2 and EK 3 profiles, finely loamy, mix, acid, isohypertermik. The land was marginally suitable (S3 for cocoa plant with the contraints of impeded drainage, acid soil

  3. [Impacts of different alkaline soil on canopy spectral characteristics of overlying vegetation].

    Science.gov (United States)

    Jia, Ke-Li; Zhang, Jun-Hua

    2014-03-01

    The relationship between alkalinity and pH of the soil, reflectance spectra and red-edge parameters of the sunflower canopy in different growth periods under different alkalinity soil were analyzed, respectively. The results showed that the spectral reflectance of the sunflower canopy in different stage under different alkalinity soil is the same as the spectral reflectance characters of the other greenery canopy. Along with the advancement of the sunflower growth period, sunflower canopy spectral reflectance increases gradually at different stages, the spectral reflectance is higher at flowering stage than 7-leaf stage and budding stage, and there exists a high reflection peak at 809nm at flowering period. At the same time, the spectral reflectance is affected by salinity-alkalinity stress at different stages, in the near infrared shortwave band, the spectral reflectance of the sunflower canopy in different stage increases with the decreases in soil alkalinity. When the derivatives are applied to determine the wavelength of the red-edge, there is a shift phenomenon of the red edge. The red edges were at 702-720 nm during every growth period of the sunflower. The "blue shift" phenomenon is also emerged for red edge position and red edge sloped with the increase in the soil alkalinity. Conversely, at the same growth periods, the red edge positions and red edge slope move to longer wave bands with the decrease in soil alkalinity. There is a "red shift" phenomenon before flowering period and "blue shift" phenomenon after flowering period for the red edge position and red edge slope of canopy spectrum at the same soil alkalinity. Respectively. The red edges at different growth stages of the sunflower show very significant positive correlation and quadratic polynomial to alkalinity and pH of the soil. Therefore, we thought used the red edge features of greenery could indicate the soil alkalization degree, it providing scientific basis for monitoring soil alkalization

  4. Characteristics of soil-to-plant transfer of elements relevant to radioactive waste in boreal forest

    International Nuclear Information System (INIS)

    Roivainen, P.

    2011-01-01

    The use of nuclear energy generates large amounts of different types of radioactive wastes that can be accidentally released into the environment. Soil-to-plant transfer is a key process for the dispersion of radionuclides in the biosphere and is usually described by a concentration ratio (CR) between plant and soil concentrations in radioecological models. Our knowledge of the soil-to-plant transfer of many radionuclides is currently limited and concerns mainly agricultural species and temperate environments. The validity of radioecological modelling is affected by the accuracy of the assumptions and parameters used to describe soil-to-plant transfer. This study investigated the soil-to-plant transfer of six elements (cobalt (Co), molybdenum (Mo), nickel (Ni), lead (Pb), uranium (U) and zinc (Zn)) relevant to radioactive waste at two boreal forest sites and assessed the factors affecting the CR values. May lily (Maianthemum bifolium), narrow buckler fern (Dryopteris carthusiana) and blueberry (Vaccinium myrtillus) were selected as representatives of understory species, while rowan (Sorbus aucuparia) and Norway spruce (Picea abies) represented trees in this study. All the elements studied were found to accumulate in plant roots, indicating that separate CR values for root and aboveground plant parts are needed. The between-species variation in CR values was not clearly higher than the within-species variation, suggesting that the use of generic CR values for understory species and trees is justified. No linear relationship was found between soil and plant concentrations for the elements studied and a non-linear equation was found to be the best for describing the dependence of CR values on soil concentration. Thus, the commonly used assumption of a linear relationship between plant and soil concentrations may lead to underestimation of plant root uptake at low soil concentrations. Plant nutrients potassium, magnesium, manganese, phosphorus and sulphur were found to

  5. Characteristics of PAHs in farmland soil and rainfall runoff in Tianjin, China.

    Science.gov (United States)

    Shi, Rongguang; Xu, Mengmeng; Liu, Aifeng; Tian, Yong; Zhao, Zongshan

    2017-10-14

    Rainfall runoff can remove certain amounts of pollutants from contaminated farmland soil and result in a decline in water quality. However, the leaching behaviors of polycyclic aromatic hydrocarbons (PAHs) with rainfall have been rarely reported due to wide variations in the soil compositions, rainfall conditions, and sources of soil PAHs in complex farmland ecosystems. In this paper, the levels, spatial distributions, and composition profiles of PAHs in 30 farmland soil samples and 49 rainfall-runoff samples from the Tianjin region in 2012 were studied to investigate their leaching behaviors caused by rainfall runoff. The contents of the Σ 16 PAHs ranged from 58.53 to 3137.90 μg/kg in the soil and 146.58 to 3636.59 μg/L in the runoff. In total, most of the soil sampling sites (23 of 30) were contaminated, and biomass and petroleum combustion were proposed as the main sources of the soil PAHs. Both the spatial distributions of the soil and the runoff PAHs show a decreasing trend moving away from the downtown, which suggested that the leaching behaviors of PAHs in a larger region during rainfall may be mainly affected by the compounds themselves. In addition, 4- and 5-ring PAHs are the dominant components in farmland soil and 3- and 4-ring PAHs dominate the runoff. Comparisons of the PAH pairs and enrichment ratios showed that acenaphthylene, acenaphthene, benzo[a]anthracene, chrysene, and fluoranthene were more easily transferred into water systems from soil than benzo[b]fluoranthene, benzo[k]fluoranthene, benzo[ghi]perylene, and indeno[123-cd]pyrene, which indicated that PAHs with low molecular weight are preferentially dissolved due to their higher solubility compared to those with high molecular weight.

  6. Characteristics of soil-to-plant transfer of elements relevant to radioactive waste in boreal forest

    Energy Technology Data Exchange (ETDEWEB)

    Roivainen, P.

    2011-07-01

    The use of nuclear energy generates large amounts of different types of radioactive wastes that can be accidentally released into the environment. Soil-to-plant transfer is a key process for the dispersion of radionuclides in the biosphere and is usually described by a concentration ratio (CR) between plant and soil concentrations in radioecological models. Our knowledge of the soil-to-plant transfer of many radionuclides is currently limited and concerns mainly agricultural species and temperate environments. The validity of radioecological modelling is affected by the accuracy of the assumptions and parameters used to describe soil-to-plant transfer. This study investigated the soil-to-plant transfer of six elements (cobalt (Co), molybdenum (Mo), nickel (Ni), lead (Pb), uranium (U) and zinc (Zn)) relevant to radioactive waste at two boreal forest sites and assessed the factors affecting the CR values. May lily (Maianthemum bifolium), narrow buckler fern (Dryopteris carthusiana) and blueberry (Vaccinium myrtillus) were selected as representatives of understory species, while rowan (Sorbus aucuparia) and Norway spruce (Picea abies) represented trees in this study. All the elements studied were found to accumulate in plant roots, indicating that separate CR values for root and aboveground plant parts are needed. The between-species variation in CR values was not clearly higher than the within-species variation, suggesting that the use of generic CR values for understory species and trees is justified. No linear relationship was found between soil and plant concentrations for the elements studied and a non-linear equation was found to be the best for describing the dependence of CR values on soil concentration. Thus, the commonly used assumption of a linear relationship between plant and soil concentrations may lead to underestimation of plant root uptake at low soil concentrations. Plant nutrients potassium, magnesium, manganese, phosphorus and sulphur were found to

  7. Structural characteristic of the Eastern Plains soils of Colombia, submitted to several handling systems

    International Nuclear Information System (INIS)

    Amezquita, E; Saenz J I; Thomas, R J; Vera, R R; Hoyos, P; Molina, D L; Chavez, L F

    1997-01-01

    Soil productivity and sustainability depends on the building and/or conservation of an adequate and dynamic equilibrium between physical, chemical and biological properties and processes in the volume of soil explored by roots, so that there is no constraints in the availability of water and nutrients to plants. Soil structure is one of the soil properties that are more vulnerable to the intensity of use in tropical soils. Aggregate size distribution, aggregate stability and pore size distribution are some of the attributes that are usually used to describe structural changes and can act as indicators of structural sustainability. This paper presents and discusses the behavior of these attributes under different soil management treatments (native savanna, Brachiaria alone; Brachiaria + legume and monocrop) in the Colombian Eastern plains soil classified as Typic haplustox Kaolinitic iso-hyperthermic. These results showed highly statistical significant differences between treatments in the parameters studied and allow concluding that aggregate size distribution and stability could be indicators of susceptibility to degradation

  8. Investigation of structure and characteristics of soil for foundation design of gamma irradiators capacity 2 MCi

    International Nuclear Information System (INIS)

    Kukuh Prayogo; Hasriyasti Saptowati

    2016-01-01

    Soil investigation conducted before the work of irradiator building structural foundation design is initiated. Intake of sample was set at some point drill at Irradiator facility site to the disturbed soil layer or not disturbed. From the results of this soil investigation will be selected as alternative / types, the depth and dimensions of the foundation of the most economical but still safe. Soil investigation method used was Deep Boring, undisturbed and disturbed sampling, SPT ( Standard Penetration Test ), CPT ( Cone Penetration Test / Sondir ). Testing conducted in the field and in the laboratory of soil mechanics to determine the mechanical properties, soil layer thickness and other physical properties for calculation of the bearing capacity of the foundation. The results of the soil investigation at the three-point drill showed the average depth of the bedrock -19.33 m and adhesion 3163.88 kg / cm’. Test boring at point BH1 found the depth of the bedrock -19.33 m and adhesion 3163.88 kg / cm’. Test boring at point BH1 found the bedrock at a depth of 32 m with a maximum SPT value 16. from the data can be determined the appropriate type of foundation is bored pile. The foundation is the upper structure support which can lead to a reduction / settlement if its bearing capacity is not able to withstand the load on it. (author)

  9. Soil, Groundwater, Surface Water, and Sediments of Kennedy Space Center, Florida: Background Chemical and Physical Characteristics

    Science.gov (United States)

    Shmalzer, Paul A.; Hensley, Melissa A.; Mota, Mario; Hall, Carlton R.; Dunlevy, Colleen A.

    2000-01-01

    This study documented background chemical composition of soils, groundwater, surface; water, and sediments of Kennedy Space Center. Two hundred soil samples were collected, 20 each in 10 soil classes. Fifty-one groundwater wells were installed in 4 subaquifers of the Surficial Aquifer and sampled; there were 24 shallow, 16 intermediate, and 11 deep wells. Forty surface water and sediment samples were collected in major watershed basins. All samples were away from sites of known contamination. Samples were analyzed for organochlorine pesticides, aroclors, chlorinated herbicides, polycyclic aromatic hydrocarbons (PAH), total metals, and other parameters. All aroclors (6) were below detection in all media. Some organochlorine pesticides were detected at very low frequencies in soil, sediment, and surface water. Chlorinated herbicides were detected at very low frequencies in soil and sediments. PAH occurred in low frequencies in soiL, shallow groundwater, surface water, and sediments. Concentrations of some metals differed among soil classes, with subaquifers and depths, and among watershed basins for surface water but not sediments. Most of the variation in metal concentrations was natural, but agriculture had increased Cr, Cu, Mn, and Zn.

  10. Physicochemical and Microbiological Characteristics of Tundra Soils on the Rybachii Peninsula

    Science.gov (United States)

    Evdokimova, G. A.; Mozgova, N. P.; Myazin, V. A.

    2018-01-01

    The Rybachii Peninsula is composed of Proterozoic sedimentary rocks and differs sharply from the rest of the Kola Peninsula in its geological structure, topographic forms, and parent rocks. It is dominated by Al-Fe-humus soils formed on moraines with an admixture of local rock fragments, including slates. Organic horizons of tundra soils in the peninsula are less acid than those on granitoids of adjacent mainland of the Kola Peninsula. The content of exchangeable calcium in the organic horizons varies from 17.4 to 68.0 cmolc/kg, and the content of water-soluble carbon reaches 400 mg/100 g amounting to 1-2% of the total soil organic matter content. The total number of bacteria in the organic horizons of tundra soils varies from 3.5 × 109 to 4.8 × 109 cells/g; and bacterial biomass varies from 0.14 to 0.19 mg/g. The length of fungal mycelium and its biomass in the organic horizons are significant (>1000 m/g soil). The biomass of fungal mycelium in the organic horizons exceeds the bacterial biomass by seven times in podzols (Albic Podzols) and by ten times in podbur (Entic Podzol), dry-peat soil (Folic Histosol), and low-moor peat soil (Sapric Histosol).

  11. [Micro-scale soil characteristics in salinization area of Songnen plain].

    Science.gov (United States)

    Luo, Jin-Ming; Wang, Yong-Jie; Deng, Wei; Ye, Ya-Jie; Zhang, Xiao-Ping

    2009-08-01

    The study by the methods of in situ observation and laboratory analysis showed that the micro-relief in salinization area of Songnen Plain area was composed of flat land, micro-slope land, depression margin, and depression. Isohumusols distributed in depression, while alkalic halosols distributed in depression margin, micro-slope land, and flat land. The exchangeable sodium percent (ESP) in alkalized layer (15-30 cm) of alkaline soil in flat land was 60%, and the maximal ESP in surface soil layer in micro-slope land could reach to 75%. The alkalized soil layer in depression margin was mainly at the depth of 10-30 cm, where the maximal ESP could reach to 30% -40%. Nearly no alkalized layer was found in the soil profile in depression. The soils developed on the four micro-relief units had obvious differences in their water retention curves. The maximal saturation moisture content in the soils of micro-slope land was only 25%, while that of 0-10 cm soil layer in depression reached to 45%. The freezing-thawing process in different micro-relief units differed markedly, with the maximal frozen depth in micro-slope land and depression being 157 and 136 cm, respectively. The surface soil moisture content in depression increased from 20% before freezing to 50% during freezing period. Among the four micro-relief units, micro-slope land had the most obvious variation of surface soil salt content during freezing-thawing, with the increment after thawing being as high as 80%.

  12. [Residual characteristics of HCHs in soils of a former lindane production enterprise].

    Science.gov (United States)

    Pan, Feng; Wang, Li-Li; Zhao, Hao; You, Qi-Zhong; Liu, Lin

    2013-02-01

    In order to study the soil pollution status of the fields left by organochlorine pesticide manufacturing enterprises, soils from a former lindane production enterprise of Xinxiang were investigated in November, 2010. A soxhlet extraction-gas chromatography-electron capture detector (SE-GC-ECD) method was used to detect the HCH residues in the contaminated soil samples. Results showed that the detection rate of the four HCHs isomers in each sampling site was 100%. In the 0-20 cm topsoil, concentrations of HCH residues (Sig;ma HCH ) changed with volatility, ranging from 0.0343 to 19.5608 mg.kg-1. In the soil layer at 0-80 cm depth and around the center point, concentrations of HCH residues (Sigma HCH ) first increased and then reduced while the soil depth increased, varying from 0.031 3 to 0.2947 mg.kg-1. Analysis of HCH composition showed that concentrations of the four isomers were in the order of beta-HCH > delta-HCH > alpha-HCH > alpha-HCH. The average percentage of p-HCH isomer was approximately 50%, which was obviously higher than those of the other isomers, indicating that there was no recent input of HCH. The results showed that over the recent decades, the HCH level in most of the soil samples (67.9%) were below the residue criterion of 0.5 mg.kg-1 of the China Soil Environmental Quality Standard (GB 15618-1995), indicating that they were safe. However, soil samples in western and eastern parts of backyard near the production plant were still seriously contaminated, the HCH concentrations in which were 1.5-20 times higher than the residue criterion of 1.0 mg.kg-1 of the China Soil Environmental Quality Standard, causing great potential safety hazard to human and environment.

  13. Pollution characteristics of 23 veterinary antibiotics in livestock manure and manure-amended soils in Jiangsu province, China.

    Science.gov (United States)

    Guo, Xin Y; Hao, Li J; Qiu, Pan Z; Chen, Rong; Xu, Jing; Kong, Xiang J; Shan, Zheng J; Wang, Na

    2016-01-01

    The aim of this study was to investigate the pollution characteristics of typical veterinary antibiotics in manure and soil of livestock farms in Jiangsu province. This investigation employed solid-phase extraction (SPE) coupled with ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). A total of 53 manure and 50 amended soil samples from 16 livestock farms in Jiangsu province were collected for analysis. In the manure samples, the highest detected frequencies and concentrations were those of tetracyclines (TCs, 54.1 ± 5775.6 μgkg(-1)), followed by fluoroquinolones (FQs, 8.4 ± 435.6 μgkg(-1)), sulphonamides (SAs, 3.2 ± 5.2 μgkg(-1)) and macrolides (MACs, 0.4 ± 110.5 μgkg(-1)). Statistical analysis was used to illuminate the pollution characteristics of 23 veterinary antibiotics for various animal types and different regions in Jiangsu province. The results showed that the pollution level in cow manure was relatively lower compared with pig and chicken manure due to the relative restriction of medication. Furthermore, contamination was serious in amended soil from chicken farms. The pollution level in manure among different regions was higher to the south and north compared with the centre of the region. The same outcome was found for soil. Antibiotic residues in organic fertilizer were also investigated in this study. We found that although the detected concentration was lower in organic fertilizer than in fresh manure, detection frequencies (10-90%) were high, especially for roxithromycin (90%) in MACs (30-90%). This finding suggests attention should be paid to the pollution levels in organic fertilizer. This study is the first extensive investigation of the occurrence and distribution of many kinds of typical veterinary antibiotics in manure and soil from livestock farms of Jiangsu province. This investigation systematically assesses veterinary antibiotics usage and related emissions in southeast China.

  14. Cadmium Sorption Characteristics of Soil Amendments and its Relationship with the Cadmium Uptake by Hyperaccumulator and Normal Plants in Amended Soils

    Science.gov (United States)

    Sun, Yan; Wu, Qi-Tang; Lee, Charles C.C.; Li, Baoqin; Long, Xinxian

    2013-01-01

    In order to select appropriate amendments for cropping hyperaccumulator or normal plants on contaminated soils and establish the relationship between Cd sorption characteristics of soil amendments and their capacity to reduce Cd uptake by plants, batch sorption experiments with 11 different clay minerals and organic materials and a pot experiment with the same amendments were carried out. The pot experiment was conducted with Sedum alfredii and maize (Zea mays) in a co-cropping system. The results showed that the highest sorption amount was by montmorillonite at 40.82 mg/g, while mica was the lowest at only 1.83 mg/g. There was a significant negative correlation between the n value of Freundlich equation and Cd uptake by plants, and between the logarithm of the stability constant K of the Langmuir equation and plant uptake. Humic acids (HAs) and mushroom manure increased Cd uptake by S. alfredii, but not maize, thus they are suitable as soil amendments for the co-cropping S. alfredii and maize. The stability constant K in these cases was 0.14–0.16 L/mg and n values were 1.51–2.19. The alkaline zeolite and mica had the best fixation abilities and significantly decreased Cd uptake by the both plants, with K ≥ 1.49 L/mg and n ≥ 3.59. PMID:24912231

  15. Rice growing farmers efficiency measurement using a slack based interval DEA model with undesirable outputs

    Science.gov (United States)

    Khan, Sahubar Ali Mohd. Nadhar; Ramli, Razamin; Baten, M. D. Azizul

    2017-11-01

    In recent years eco-efficiency which considers the effect of production process on environment in determining the efficiency of firms have gained traction and a lot of attention. Rice farming is one of such production processes which typically produces two types of outputs which are economic desirable as well as environmentally undesirable. In efficiency analysis, these undesirable outputs cannot be ignored and need to be included in the model to obtain the actual estimation of firm's efficiency. There are numerous approaches that have been used in data envelopment analysis (DEA) literature to account for undesirable outputs of which directional distance function (DDF) approach is the most widely used as it allows for simultaneous increase in desirable outputs and reduction of undesirable outputs. Additionally, slack based DDF DEA approaches considers the output shortfalls and input excess in determining efficiency. In situations when data uncertainty is present, the deterministic DEA model is not suitable to be used as the effects of uncertain data will not be considered. In this case, it has been found that interval data approach is suitable to account for data uncertainty as it is much simpler to model and need less information regarding the underlying data distribution and membership function. The proposed model uses an enhanced DEA model which is based on DDF approach and incorporates slack based measure to determine efficiency in the presence of undesirable factors and data uncertainty. Interval data approach was used to estimate the values of inputs, undesirable outputs and desirable outputs. Two separate slack based interval DEA models were constructed for optimistic and pessimistic scenarios. The developed model was used to determine rice farmers efficiency from Kepala Batas, Kedah. The obtained results were later compared to the results obtained using a deterministic DDF DEA model. The study found that 15 out of 30 farmers are efficient in all cases. It

  16. Geochemical characteristics of rare earth elements in different types of soil: A chemometric approach.

    Science.gov (United States)

    Khan, Aysha Masood; Behkami, Shima; Yusoff, Ismail; Md Zain, Sharifuddin Bin; Bakar, Nor Kartini Abu; Bakar, Ahmad Farid Abu; Alias, Yatimah

    2017-10-01

    Rare earth elements (REEs) are becoming significant due to their huge applications in many industries, large-scale mining and refining activities. Increasing usage of such metals pose negative environmental impacts. In this research ICP-MS has been used to analyze soil samples collected from former ex-mining areas in the depths of 0-20 cm, 21-40 cm, and 41-60 cm of residential, mining, natural, and industrial areas of Perak. Principal component analysis (PCA) revealed that soil samples taken from different mining, industrial, residential, and natural areas are separated into four clusters. It was observed that REEs were abundant in most of the samples from mining areas. Concentration of the rare elements decrease in general as we move from surface soil to deeper soils. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. LBA-ECO LC-21 Soil Characteristics, Logged Areas, Tapajos Forest, Para, Brazil: 2003

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set provides measurements for soil nutrients from areas that were selectively logged and from control areas in the Tapajos National Forest, Para Western...

  18. LBA-ECO LC-21 Soil Characteristics, Logged Areas, Tapajos Forest, Para, Brazil: 2003

    Data.gov (United States)

    National Aeronautics and Space Administration — ABSTRACT: This data set provides measurements for soil nutrients from areas that were selectively logged and from control areas in the Tapajos National Forest, Para...

  19. LBA-ECO CD-09 Soil and Vegetation Characteristics, Tapajos National Forest, Brazil

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set reports the results of soil and vegetation surveys at four distinct areas within the Tapajos National Forest (TNF), 50 to 100 km south of Santarem,...

  20. Computer aided modeling of soil mix designs to predict characteristics and properties of stabilized road bases.

    Science.gov (United States)

    2009-07-01

    "Considerable data exists for soils that were tested and documented, both for native properties and : properties with pozzolan stabilization. While the data exists there was no database for the Nebraska : Department of Roads to retrieve this data for...

  1. LBA-ECO CD-09 Soil and Vegetation Characteristics, Tapajos National Forest, Brazil

    Data.gov (United States)

    National Aeronautics and Space Administration — ABSTRACT: This data set reports the results of soil and vegetation surveys at four distinct areas within the Tapajos National Forest (TNF), 50 to 100 km south of...

  2. [Distribution characteristics of soil organic carbon under different forest restoration modes on opencast coal mine dump].

    Science.gov (United States)

    Wen, Yue-rong; Dang, Ting-hui; Tang, Jun; Li, Jun-chao

    2016-01-01

    The content and storage of soil organic carbon (SOC) were compared in six wood restoration modes and adjacent abandoned land on opencast coal mine dump, and the mechanisms behind the differences and their influencing factors were analyzed. Results showed that the contents of SOC in six wood lands were significantly higher (23.8%-53.2%) than that of abandoned land (1.92 g · kg⁻¹) at 0-10 cm soil depth, the index were significantly higher (5.8%-70.4%) at 10-20 cm soil depth than the abandoned land (1.39 g · kg⁻¹), and then the difference of the contents of SOC in the deep soil (20-100 cm) were not significant. The contents of SOC decreased with increase of soil depth, but the decreasing magnitude of the topsoil (0-20 cm) was higher than that of the deep soil (20-100 cm). Compared with the deep soil, the topsoil significant higer storage of SOC in different woods, the SOC storage decreased with the soil depth. Along the 0-100 cm soil layer, the storage of SOC in six wood lands higher (18.1%-42.4%) than that of the abandoned land (17.52 t · hm⁻²). The SOC storage of Amorpha fruticosa land (24.95 t · hm⁻²) was obviously higher than that in the other wood lands. The SOC storage in the shrub lands was 12.4% higher than that of the arbor woods. There were significantly positive correlations among forest litter, fine root biomass, soil water content and SOC on the dump. Consequently, different plantation restorations significantly improved the SOC level on the dump in 0-100 cm soil, especially the topsoil. But there was still a big gap about SOC level between the wood restoration lands and the original landform. To improve the SOC on opencast coal mine dump, A. fruticosa could be selected as the main wood vegetation.

  3. Spectral characteristics of dissolved organic matter in various agricultural soils throughout China.

    Science.gov (United States)

    Gao, Jiakai; Liang, Chenglong; Shen, Guangzhu; Lv, Jialong; Wu, Haiming

    2017-06-01

    Dissolved organic matter (DOM) plays an essential role in many environmental processes, particularly in soil ecosystems. In the present study, ultraviolet-visible (UV-Vis) spectroscopy and parallel factor analysis (PARAFAC) of three-dimensional fluorescence excitation-emission matrices (3D-EEMs) were used to characterize DOM extracted from various agricultural soils across four climate regions of China. The maximum (86.01 mg L -1 ) and minimum (17.39 mg L -1 ) dissolved organic carbon (DOC) concentrations were found in soils from Jiangsu and Yunnan, respectively. Specific UV-Vis absorption at 254 nm (SUVA 254 ) for soil DOM from the temperate continental climate (TCC) region was higher than that of soil DOM in other climate regions. Three fluorescence components including UVC humic-like substances (excitation peak at 400 nm, emission peak at 525 nm), UVA humic-like substances (250(330)/430 nm), and tyrosine-like materials (220(275)/320 nm) were identified in soil DOM using PARAFAC analysis. However, there were no significant differences in the distributions of these three components for soil DOM from different climate regions. Positive correlations were found among the humification index (HIX), fluorescence index (FI), and autochthonous index (BIX). Our results demonstrate that EEMs-PARAFAC could be a feasible approach for characterizing DOM in agricultural soils from different crop systems and can be used to further study complex DOM in agricultural environments. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Spectroscopic Characteristics of Dissolved Organic Matter in Afforestation Forest Soil of Miyun District, Beijing

    Science.gov (United States)

    Zhao, Chen; Shi, Zong-Hai; Zhong, Jun; Liu, Jian-Guo; Li, Jun-Qing

    2016-01-01

    In this study, soil samples collected from different plain afforestation time (1 year, 4 years, 10 years, 15 years, and 20 years) in Miyun were characterized, including total organic carbon (TOC), total nitrogen (TN), total phosphorus (TP), available K (K+), microbial biomass carbon (MBC), and dissolved organic carbon (DOC). The DOM in the soil samples with different afforestation time was further characterized via DOC, UV-Visible spectroscopy, excitation-emission matrix (EEM) fluorescence spectroscopy, and 1H NMR spectroscopy. The results suggested that the texture of soil sample was sandy. The extracted DOM from soil consisted mainly of aliphatic chains and only a minor aromatic component. It can be included that afforestation can improve the soil quality to some extent, which can be partly reflected from the indexes like TOC, TN, TP, K+, MBC, and DOC. And the characterization of DOM implied that UV humic-like substances were the major fluorophores components in the DOM of the soil samples, which consisted of aliphatic chains and aromatic components with carbonyl, carboxyl, and hydroxyl groups. PMID:27433371

  5. Nitrous oxide uptake rates in boreal coniferous forests are associated with soil characteristics

    Science.gov (United States)

    Siljanen, Henri; Biasi, Christina; Martikainen, Pertti

    2014-05-01

    Nitrous oxide (N2O) is a strong greenhouse gas and a significant contributor to the destruction of the ozone layer. The radiative forcing of N2O is considered to be 320 more efficient than carbon dioxide.The major portion of global N2O is emitted from agricultural soils. There are studies suggesting that N2O has also a sink in forest soils. However there is relatively limited knowledge on factors controlling N2O consumption in forest soils. Hence N2O consumption was studied in boreal coniferous forests having different forest cover, soil chemical and physical structure and land-use history. The N2O consumption was measured by static chamber technique in the field across spatio-seasonal sampling design. Typical and atypical denitrifiers were quantified with nosZ functional gene marker. Additionally chemical and physical environmental parameters were analyzed to link N2O flux, microbial community and composition of soils. Nitrous oxide uptake could be associated with specific ecosystem and environmental conditions. Soil physical structure and land-use history were shown to be prior factors determining the strength of the uptake rate.

  6. Main Feedbacks Between Oxidizable Carbon Content and Selected Soil Characteristic of Chernozem

    Directory of Open Access Journals (Sweden)

    Vítězslav Vlček

    2015-01-01

    Full Text Available Anthropogenic pressure on our agricultural land is culminating last hundred years, especially after 1948, not only because of only massive application of mineral fertilizers but also because of land consolidation and subsequent accelerated water and wind erosion and use of mechanization. This article focuses on main demonstration of feedbacks especially with oxidizable carbon which can negatively affect soil as a homeostatic system. Oxidizable carbon, as the basis of soil humus, is crucial for maintaining soil fertility and for its resistance to further degradation factors affecting the soil. 35 chernozem sites were selected in South Moravia region. These soils had been probably used for their fertility and availability before the turn of the AD. Unfortunately, their long-term agricultural use has resulted in adverse impact on their quality.This way, shallower forms of erosion were often formed. These erosion forms are omitted for the purposes of our study there. For this work, locations with preserved chernic (i.e. diagnostic horizon, as the horizon with less anthropogenic influence, were selected. Relations between a grain size (clay, silt and sand particles, exchange reaction in soil, sorption capacity, oxidizable carbon content, total nitrogen content and content of selected potentially acceptable elements (Ca, Mg were monitored.

  7. Influence of agrochemical characteristics of 85Sr and 137Cs in soil samples from the localities around nuclear power plants in Slovak Republic

    International Nuclear Information System (INIS)

    Cipakova, A.; Mitro, A.

    1997-01-01

    Sorption of radiostrontium and radiocesium, two biologically available radionuclides in soils was studied. Experiments were carried out on the soil samples from the localities around nuclear power plants. Adsorption processes are the function of many factors. Multi-para-metrical regression analysis was used for studying of the influence of agrochemical characteristics on sorption of 85 Sr and 137 Cs in observed soil types. (authors)

  8. A Test Study to Display Buried Anti-Tank Landmines with GPR and Research Soil Characteristics with CRS

    Science.gov (United States)

    Kadioglu, Selma; Kagan Kadioglu, Yusuf

    2014-05-01

    An anti-tank mine (AT mine) is a type of land mine designed to damage or destroy vehicles including tanks and armored fighting vehicles. Anti-tank mines typically have a much larger explosive charge, and a fuze designed only to be triggered by vehicles or, in some cases, tampering with the mine. There are a lot of AT mine types. In our test study, MK4 and MK5 AT mine types has been used. The Mk 5 was a cylindrical metal cased U.K. anti-tank blast mine that entered service in 1943, during the Second World War. General Specifications of them are 203 mm diameter, 127 mm height, 4.4-5.7 kg weight, 2.05-3.75 kg of TNT explosive content and 350 lbs operating pressure respectively. The aims of the test study were to image anti-tank landmine with GPR method and to analyse the soil characteristics before the mines made explode and after made be exploded and determine changing of the soil characteristics. We realized data measurement on the real 6 unexploded anti-tank landmine buried approximately 15 cm in depth. The mines spaced 3 m were buried in two lines. Space between lines was 1.5 m. We gathered data on the profiles, approximately 7 m, with a Ramac CUII system and 800 MHz shielded antenna. We collected soil samples on the mines, near and around the mines, on the area in village. We collected soil samples before exploding and after exploding mines. We imaged anti-tank landmines on the depth slices of the GPR data and in their interactive transparent 3D subsets successfully. We used polarized microscope and confocal Raman spectroscopy (CRS) to identify soil characteristic before and after exploitation. The results presented that GPR method and its 3D imaging were successful to determine AT mines, and there was no important changing on mineralogical and petrographical characterization of the soil before and after exploding processing. This project has been supported by Ankara University under grant no 11B6055002. The study is a contribution to the EU funded COST action TU

  9. The Influences of Soil Characteristics on Nest-Site Selection in Painted Turtles (Chrysemys picta)

    Science.gov (United States)

    Page, R.

    2017-12-01

    A variety of animals dig nests and lay their eggs in soil, leaving them to incubate and hatch without assistance from the parents. Nesting habitat is important for these organisms many of which exhibit temperature dependent sex determination (TSD) whereby the incubation temperature determines the sex of each hatchling. However, suitable nesting habitat may be limited due to anthropogenic activities and global temperature increases. Soil thermal properties are critical to these organisms and are positively correlated with water retention and soil carbon; carbon-rich soils result in higher incubation temperatures. We investigated nest-site selection in painted turtles (Chrysemys picta) inhabiting an anthropogenic pond in south central Pennsylvania. We surveyed for turtle nests and documented location, depth, width, temperature, canopy coverage, clutch size, and hatch success for a total of 31 turtle nests. To address the influence of soil carbon and particle size on nest selection, we analyzed samples collected from: 1) actual nests that were depredated, 2) false nests, incomplete nests aborted during digging prior to nest completion, and 3) randomized locations. Soil samples were separated into coarse, medium, and fine grain size fractions through a stack of sieves. Samples were combusted in a total carbon analyzer to measure weight percent organic carbon. We found that anthropogenic activity at this site has created homogenous, sandy, compacted soils at the uppermost layer that may limit females' access to appropriate nesting habitat. Turtle nesting activity was limited to a linear region north of the pond and was constrained by an impassable rail line. Relative to other studies, turtle nests were notably shallow (5.8±0.9 cm) and placed close to the pond. Compared to false nests and random locations, turtle-selected sites averaged greater coarse grains (35% compared to 20.24 and 20.57%) and less fine grains (47% compared to 59 and 59, respectively). Despite

  10. Experimental investigation of undesired stable equilibria in pumpkin shape super-pressure balloon designs

    Science.gov (United States)

    Schur, W. W.

    2004-01-01

    Excess in skin material of a pneumatic envelope beyond what is required for minimum enclosure of a gas bubble is a necessary but by no means sufficient condition for the existence of multiple equilibrium configurations for that pneumatic envelope. The very design of structurally efficient super-pressure balloons of the pumpkin shape type requires such excess. Undesired stable equilibria in pumpkin shape balloons have been observed on experimental pumpkin shape balloons. These configurations contain regions with stress levels far higher than those predicted for the cyclically symmetric design configuration under maximum pressurization. Successful designs of pumpkin shape super-pressure balloons do not allow such undesired stable equilibria under full pressurization. This work documents efforts made so far and describes efforts still underway by the National Aeronautics and Space Administration's Balloon Program Office to arrive on guidance on the design of pumpkin shape super-pressure balloons that guarantee full and proper deployment.

  11. Vegetation succession and soil infiltration characteristics under different aged refuse dumps at the Heidaigou opencast coal mine

    Directory of Open Access Journals (Sweden)

    Huang Lei

    2015-07-01

    Full Text Available Vegetation succession and soil infiltration characteristics under five different restoration models of refuse dumps including different-aged revegetated sites (1995, 1998, 2003 and 2005 in the northern, eastern and western open-pit coal mine dump and a reference site with native vegetation, which had never been damaged by coal mining activities on the Heidaigou Open Cut Coal Mine were studied. Changes in the plant species, soil properties and infiltration rates were evaluated at the different refuse dumps. The results indicated that the number of herbaceous species, plant cover, biomass, fine particles, and total N, P and SOM increased significantly with increasing site age. However, the number of shrub species decreased since revegetation, its cover increased from 17% to 41% initially and subsequently decreased to the present level of 4%. The natural vegetation community and the northern refuse dump had the highest cumulative infiltration rates of 3.96 and 2.89 cm s−1 in contrast to the eastern and western refuse dumps and the abandoned land, where the highest cumulative infiltration rates were 1.26, 1.04 and 0.88 cm s−1, respectively. A multiple linear regression analysis indicated that the infiltration rate was primarily determined by the silt percentage, SOM, plant coverage and the variation in soil bulk density. Our results provide new ideas regarding future soil erosion controls and sustainable development at open-pit coal mine refuse dumps.

  12. [Effect of Water Extracts from Rhizosphere Soil of Cultivated Astragalus membranaceus var. mongholicus on It's Seed Germination and Physiological Characteristics].

    Science.gov (United States)

    Lang, Duo-yong; Fu, Xue-yan; Rong, Jia-wang; Zhang, Xin-hui

    2015-01-01

    To explore the relationship between continuous cropping obstacle and autotoxicity of Astragalus membranaceus var. mongholicus. Distilled water(CK), water extracts of rhizosphere soil(50, 100, 200 and 400 mg/mL) were applied to test their effect on early growth and physiological characteristics of Astragalus membranaceus var. mongholicus. The water extracts from rhizospher soil of cultivated Astragalus membranaceus var. mongholicus significantly increased seedling emergence rate, root length and vigor index of Astragalus membranaceus var. mongholicus seedling when at the concentration of 100 mg/mL or below, however,there was no significant effect at 200 mg/mL or higher. The water extracts from rhizosphere soil of cultivated Astragalus membranaceus var. mongholicus significantly reduced the SOD activity in Astragalus membranaceus var. mongholicus seedling at 400 mg/mL and POD activity at 200 mg/mL and 400 mg/mL,while significantly increased the MDA content. Water extracts from Astragalus membranaceus var. mongholicus rhizosphere soil significantly affected Astragalus membranaceus var. mongholicus germination and seedling growth in a concentration-dependent manner, generally, low concentrations increased the SOD and POD activity which improved seed germination and seedling growth, while high concentrations caused cell membrane damage of the seedling.

  13. Contamination characteristics and source apportionment of methylated PAHs in agricultural soils from Yangtze River Delta, China.

    Science.gov (United States)

    Chen, Weixiao; Wu, Xinyi; Zhang, Haiyun; Sun, Jianteng; Liu, Wenxin; Zhu, Lizhong; Li, Xiangdong; Tsang, Daniel C W; Tao, Shu; Wang, Xilong

    2017-11-01

    Alkylated PAHs (APAHs) have been shown to be more toxic and persistent than their non-alkylated parent compounds. However, little is known about the extent of soil contamination by these pollutants. To help understand agricultural soil pollution by these compounds at a regional scale, a total of 18 methylated PAHs (MPAHs, a major class of APAHs) in 243 soil samples were analyzed. These soil samples were collected from 11 sites in the Yangtze River Delta (YRD) region, a representative fast developing area in China. The total concentration of MPAHs (∑18MPAHs) ranged from 5.5 to 696.2 ng/g dry soil, with methylnaphthalenes (M-NAPs) and methylphenanthrenes (M-PHEs) accounting for more than 70% of the compositional profile. Relatively high concentrations of ∑18MPAHs were found in Jiaxing and Huzhou areas of Zhejiang province, as well as on the border between the cities of Wuxi and Suzhou. Different MPAH groups showed dissimilar spatial distribution patterns. The spatial distribution of lower molecular weight MPAHs was related to agricultural straw burning and emissions/depositions from industrial activities, whereas that of higher molecular weight MPAHs was much more a function of the total organic carbon (TOC) content of soil. Although coal, biomass (crop straw and wood), and petroleum combustion were identified to be the major emission sources for most of the sampling sites, the areas with relatively severe pollution with ∑18MPAHs resulted from the localized hotspots of petroleum leakage. Isomeric MPAHs with methyl group substituted at 2- (β) position exhibited significantly higher concentrations than those substituted at 1- (α) position. Results of this work help to understand soil pollution by MPAHs, and are useful for designing effective strategies for pollution control so as to ensure food safety in areas with fast economic growth. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Changes in microbial community characteristics and soil organic matter with nitrogen additions in two tropical forests.

    Science.gov (United States)

    Cusack, Daniela F; Silver, Whendee L; Torn, Margaret S; Burton, Sarah D; Firestone, Mary K

    2011-03-01

    Microbial communities and their associated enzyme activities affect the amount and chemical quality of carbon (C) in soils. Increasing nitrogen (N) deposition, particularly in N-rich tropical forests, is likely to change the composition and behavior of microbial communities and feed back on ecosystem structure and function. This study presents a novel assessment of mechanistic links between microbial responses to N deposition and shifts in soil organic matter (SOM) quality and quantity. We used phospholipid fatty acid (PLFA) analysis and microbial enzyme assays in soils to assess microbial community responses to long-term N additions in two distinct tropical rain forests. We used soil density fractionation and 13C nuclear magnetic resonance (NMR) spectroscopy to measure related changes in SOM pool sizes and chemical quality. Microbial biomass increased in response to N fertilization in both tropical forests and corresponded to declines in pools of low-density SOM. The chemical quality of this soil C pool reflected ecosystem-specific changes in microbial community composition. In the lower-elevation forest, there was an increase in gram-negative bacteria PLFA biomass, and there were significant losses of labile C chemical groups (O-alkyls). In contrast, the upper-elevation tropical forest had an increase in fungal PLFAs with N additions and declines in C groups associated with increased soil C storage (alkyls). The dynamics of microbial enzymatic activities with N addition provided a functional link between changes in microbial community structure and SOM chemistry. Ecosystem-specific changes in microbial community composition are likely to have far-reaching effects on soil carbon storage and cycling. This study indicates that microbial communities in N-rich tropical forests can be sensitive to added N, but we can expect significant variability in how ecosystem structure and function respond to N deposition among tropical forest types.

  15. Development of Data Envelopment Analysis for the Performance Evaluation of Green Supply Chain with Undesirable Outputs

    Directory of Open Access Journals (Sweden)

    Alireza Alinezhad

    2016-08-01

    Full Text Available A fundamental problem is the use of DEA in multistep or multilevel processes such as supply chain, lack of attention to processes’ internal communications in a way that the recent studies on DEA in the context of serial processes have focused on closed systems that the outputs of one level become the inputs of the next level and none of the inputs enter the mediator process. The present study aimed to examine the general dimensions of an open multilevel process. Here, some of the data such as inputs and outputs are supposed to leave the system while other outputs turn into the inputs of the next level. The new inputs can enter the next level as well. We expand this mode for network structures. The overall performance of such a structure is considered as a weighted average of sectors’ performance or distinct steps. Therefore, this suggested model in this study, not only provides the possibility to evaluate the performance of the entire network, but creates the performance analysis for each of the sub-processes. On the other hand, considering the data with undesirable structure leads to more correct performance estimation. In the real world, all productive processes do not comprise desirable factors. Therefore, presenting a structure that is capable of taking into account the undesirable structure is of crucial importance. In this study, a new model in the DEA by network structure is offered that can analyze the performance considering undesirable factors.

  16. Assessment of undesirable dose to eye-melanoma patients after proton radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Stolarczyk, L., E-mail: liliana.stolarczyk@ifj.edu.p [Henryk Niewodniczanski Institute of Nuclear Physics, Polish Academy of Sciences, ul. Radzikowskiego 152, 31-342 Krakow (Poland); Olko, P.; Cywicka-Jakiel, T.; Ptaszkiewicz, M.; Swakon, J.; Dulny, B.; Horwacik, T.; Obryk, B. [Henryk Niewodniczanski Institute of Nuclear Physics, Polish Academy of Sciences, ul. Radzikowskiego 152, 31-342 Krakow (Poland); Waligorski, M.P.R. [Henryk Niewodniczanski Institute of Nuclear Physics, Polish Academy of Sciences, ul. Radzikowskiego 152, 31-342 Krakow (Poland); Maria Sklodowska-Curie Memorial Institute, Centre of Oncology, Krakow Division, ul. Garncarska 11, 31-115, Krakow (Poland)

    2010-12-15

    Radiotherapy with a proton beam of initial energy 55-80 MeV is presently the clinically recommended therapy for some cases of intraocular melanoma such as large melanomas or tumours adjacent to critical organs. Evaluation and optimization of radiation doses outside the treatment volume may contribute to reducing undesirable side-effects and decreasing the risk of occurrence of secondary cancers, particularly for paediatric patients. In this work the undesired doses to organs were assessed basing on Monte Carlo calculation of secondary radiation transport and on results of measurements of neutron and {gamma}-ray doses at the proton therapy facility of the Institute of Nuclear Physics at Krakow. Dosimetry was performed using a He-3-based FHT 762 neutron monitor (Wendi II), a FH40G proportional counter (for {gamma}-rays), and MTS-7 (LiF:Mg,Ti) thermoluminescence detectors (TLDs). Organ doses were calculated in the ADAM anthropomorphic phantom using the MCNPX Monte Carlo transport code and partly verified, for {gamma}-ray doses, with TLD measurements in the RANDO Anderson anthropomorphic phantom. The effective dose due to undesired radiation, including exposure from scattered radiation during the entire process of proton radiotherapy and patient positioning using X-rays, does not exceed 1 mSv.

  17. Characteristics of moisture and salinity of soil in Taklimakan Desert, China.

    Science.gov (United States)

    Wang, Zhimin; Li, Guomin; Li, Xue; Shan, Shuo; Zhang, Jiangyi; Li, Shengyu; Fan, Jinglong

    2012-01-01

    The Taklimakan desert is known as the largest dunefield in China and also as the world's second largest shifting sand desert. The Tarim Desert Highway, which is the first highway to cross the Taklimakan desert, was built for the purpose of oil and gas resources extraction in the Tarim area, as well as for the development of the southern area of the Xinjiang Uygur Autonomous Region. Shelterbelts have been planted along the highway to prevent shifting sand from burying the road. This paper analyzes the variations of moisture and salinity of the unirrigated desert soil under natural conditions in the center of Taklimakan Desert. A number of important findings indicating the moisture and salinity of the soil at capillary saturation zone were determined by the groundwater and related to the evaporation on the top. Salinity could be affected by vegetation, which was different from moisture in the soil. Meanwhile, clay layer played an important role in water preservation in the soil, which was also beneficial to the accumulation of salinity in soil. Compared with clay layer, vegetation was a decisive factor for the gathering of salinity. The findings were significant for reasonable adjustment of irrigation in the shelterbelts for the further development of the Tarim Desert Highway.

  18. The study on dynamic characteristics of soil erosion in Yuyao City of Zhejiang Province

    Science.gov (United States)

    Zou, Yefeng; Zhang, Jinjuan; Li, Gang; Shen, Zhaowei; Lu, Fangchun; Zhou, Xijiong

    2017-08-01

    Taking Yuyao city as the study area, using GIS technology to establish a database of soil ero-sion. Based on the database, soil erosion in the study area was Evaluated and the dynamic variation of soil erosion intensity was analyzed. The results showed that during the past ten years from 2004-2014, the overall situation of soil erosion in Yuyao city had improved, and the total area of soil erosion decreased year by year, with an average annual reduction rate of 3.3199 km2/a. But high intensity erosion area increased due to mining, quarrying, road building caused by. And some area had the evil trend, however the area was not large. In the process of the dynamic transition of erosion, the weakening area of erosion mainly came from the transition of slightly eroded area to non-apparently eroded area. the exacerbating erosion area mainly came from the transition of non-apparently eroded area to the slightly and moderately eroded area.

  19. Behavior of granular rubber waste tire reinforced soil for application in geosynthetic reinforced soil wall

    Directory of Open Access Journals (Sweden)

    G. G. D. RAMIREZ

    Full Text Available AbstractLarge quantities of waste tires are released to the environment in an undesirable way. The potential use of this waste material in geotechnical applications can contribute to reducing the tire disposal problem and to improve strength and deformation characteristics of soils. This paper presents a laboratory study on the effect of granular rubber waste tire on the physical properties of a clayey soil. Compaction tests using standard effort and consolidated-drained triaxial tests were run on soil and mixtures. The results conveyed an improvement in the cohesion and the angle of internal friction the clayey soil-granular rubber mixture, depending on the level of confining stress. These mixtures can be used like backfill material in soil retaining walls replacing the clayey soil due to its better strength and shear behavior and low unit weight. A numerical simulation was conducted for geosynthetic reinforced soil wall using the clayey soil and mixture like backfill material to analyzing the influence in this structure.

  20. Temperature-dependent residual shear strength characteristics of smectite-bearing landslide soils

    Science.gov (United States)

    Shibasaki, Tatsuya; Matsuura, Sumio; Hasegawa, Yoichi

    2017-02-01

    This paper presents experimental investigations regarding the effect of temperature on the residual strength of landslide soils at slow-to-moderate shearing velocities. We performed ring-shear tests on 23 soil samples at temperatures of 6-29°C. The test results show that the shear strength of smectite-rich soils decreased when temperatures were relatively low. These positive temperature effects (strength losses at lower temperatures) observed for smectite-bearing soils are typical under relatively slow shearing rates. In contrast, under relatively high shearing rates, strength was gained as temperature decreased. As rheological properties of smectite suspensions are sensitive to environmental factors, such as temperature, pH, and dissolved ions, we inferred that temperature-dependent residual strengths of smectitic soils are also attributed to their specific rheological properties. Visual and scanning electron microscope observations of Ca-bentonite suggest that slickensided shear surfaces at slow shearing rates are very shiny and smooth, whereas those at moderate shearing rates are not glossy and are slightly turbulent, indicating that platy smectite particles are strongly orientated at slow velocities. The positive temperature effect is probably due to temperature-dependent microfriction that is mobilized in the parallel directions of the sheet structure of hydrous smectite particles. On the contrary, the influence of microviscous resistance, which appears in the vertical directions of the lamination, is assumed to increase at faster velocities. Our results imply that if slip-surface soils contain high fractions of smectite, decreases in ground temperature can lead to lowered shear resistance of the slip surface and trigger slow landslide movement.

  1. Flotation and adherence characteristics of Toxocara canis and T. cati and a reliable method for recovering Toxocara eggs from soil.

    Science.gov (United States)

    Kleine, Annika; Janecek, Elisabeth; Waindok, Patrick; Strube, Christina

    2016-08-30

    Toxocara canis and T. cati are worldwide distributed intestinal nematodes of canids and felids and pose a threat to public health due to possible clinical manifestations in humans. Different methods for detection of Toxocara eggs in soil have been described, but conducted studies deal with egg recovery rates of T. canis or "Toxocara spp." only whereas T. cati egg recovery has not been taken into consideration. Thus, flotation properties in sodium chloride solution and adherence characteristics to different substrates possibly coming into contact with Toxocara eggs before or during purification from soil were evaluated for both, T. canis and T. cati eggs. No significant difference was observed in flotation characteristics, but comparison of adherence properties revealed significantly less adherence of T. cati eggs on almost all evaluated substrates ("sand", side sealed bags, glass beaker, centrifuge tube) and different washing solutions (tap water, Tween(®) 80, Triton™ X-100). Mean adhesion rates of T. cati eggs ranged from 15.9% to 68.9%, those of T. canis eggs from 28.3% to 83.9%. While adherence of T. cati eggs on any substrate was significantly reduced when rinsing with Tween(®) 80 solution, no effect on T. canis eggs could be observed. Generally, Toxocara eggs adhere better on plastic than on glass. Evaluation of a method including only non-hazardous substances for purification of Toxocara eggs from soil resulted in a statistically significant higher recovery rate of T. canis (42.6% recovered eggs) compared to T. cati eggs (30.9% recovered eggs). As these percentages are above average for described methods to recover Toxocara eggs from soil, the presented method is considered reliable for prevalence studies. Copyright © 2016 Elsevier B.V. All rights reserved.

  2. Characteristics of microbial volatile organic compound flux rates from soil and plant litter

    Science.gov (United States)

    Gray, C. M.; Fierer, N.

    2013-12-01

    Our knowledge of microbial production and consumption of volatile organic compounds (VOCs) from soil and litter, as well as which microorganisms are involved, is relatively limited compared to what we know about VOC emissions from terrestrial plants. With climate change expecting to alter plant community composition, nitrogen (N) deposition rates, mean annual temperatures, precipitation patterns, and atmospheric VOC concentrations, it is unknown how microbial production and consumption of VOCs from litter and soil will respond. We have spent the last 5 years quantifying VOC flux rates in decaying plant litter, mineral soils and from a subalpine field site using a proton transfer reaction mass spectrometer (PTR-MS). Microbial production, relative to abiotic sources, accounted for 78% to 99% of the total VOC emissions from decomposing litter, highlighting the importance of microbial metabolisms in these systems. Litter chemistry correlated with the types of VOCs emitted, of which, methanol was emitted at the highest rates from all studies. The net emissions of carbon as VOCs was found to be up to 88% of that emitted as CO2 suggesting that VOCs likely represent an important component of the carbon cycle in many terrestrial systems. Nitrogen additions drastically reduced VOC emissions from litter to near zero, though it is still not understood whether this was due to an increase in consumption or a decrease in production. In the field, the root system contributed to 53% of the carbon that was emitted as VOCs from the soil with increasing air temperatures correlating to an increase in VOC flux rates from the soil system. Finally, we are currently utilizing next generation sequencing techniques (Illumina MiSeq) along with varying concentrations of isoprene, the third most abundant VOC in the atmosphere behind methane and methanol, above soils in a laboratory incubation to determine consumption rates and the microorganisms (bacteria, archaea and fungi) associated with the

  3. Spatial and Seasonal Variation of dissolved organic carbon (DOC) concentrations in Irish streams: importance of soil and topography characteristics.

    Science.gov (United States)

    Liu, Wen; Xu, Xianli; McGoff, Nicola M; Eaton, James M; Leahy, Paul; Foley, Nelius; Kiely, Gerard

    2014-05-01

    Dissolved organic carbon (DOC) concentrations have increased in many sites in Europe and North America in recent decades. High DOC concentrations can damage the structure and functions of aquatic ecosystems by influencing water chemistry. This study investigated the spatial and seasonal variation of DOC concentrations in Irish streams across 55 sites at seven time occasions over 1 year (2006/2007). The DOC concentrations ranged from 0.9 to 25.9 mg/L with a mean value of 6.8 and a median value of 5.7 mg/L and varied significantly over the course of the year. The DOC concentrations from late winter (February: 5.2 ± 3.0 mg/L across 55 sites) and early spring (April: 4.5 ± 3.5 mg/L) had significantly lower DOC concentrations than autumn (October: mean 8.3 ± 5.6 mg/L) and early winter (December: 8.3 ± 5.1 mg/L). The DOC production sources (e.g., litterfall) or the accumulation of DOC over dry periods might be the driving factor of seasonal change in Irish stream DOC concentrations. Analysis of data using stepwise multiple linear regression techniques identified the topographic index (TI, an indication of saturation-excess runoff potential) and soil conditions (organic carbon content and soil drainage characteristics) as key factors in controlling DOC spatial variation in different seasons. The TI and soil carbon content (e.g., soil organic carbon; peat occurrence) are positively related to DOC concentrations, while well-drained soils are negatively related to DOC concentrations. The knowledge of spatial and seasonal variation of DOC concentrations in streams and their drivers are essential for optimum riverine water resources management.

  4. The bearing capacity factor N γ of strip footings on c-ϕ-γ soil using the method of characteristics.

    Science.gov (United States)

    Han, Dongdong; Xie, Xinyu; Zheng, Lingwei; Huang, Li

    2016-01-01

    The method of characteristics (also called as the slip-line method) is used to calculate the bearing capacity of strip footings on ponderable soil. The soil is assumed to be a rigid plastic that conforms to the Mohr-Coulomb criterion. The solution procedures proposed in this paper is implemented using a finite difference method and suitable for both smooth and rough footings. By accounting for the influence of the cohesion c, the friction angle ϕ and the unit weight γ of the soil in one failure mechanism, the solution can strictly satisfy the required boundary conditions. The numerical solution of N γ are consistent with published complete solutions based on cohesionless soil with no surcharge load. The relationship of N γ between smooth and rough foundations is discussed which indicates that the value of N γ for a smooth footing is only half or more of that for a rough footing. The influence of λ (λ = (q + ccot ϕ)/γB) on N γ is studied. Finally, a curve-fitting formula that simultaneously considers both ϕ and λ is proposed and is used to produce a series of N γ versus λ curves. The surcharge ratio λ and roughness of the footing base both have significant impacts on N γ . The formula for the bearing capacity on c-ϕ-γ soil can be still expressed by Terzaghi's equation except that the bearing capacity factor N γ depends on the surcharge ratio λ in addition to the friction angle ϕ. Comparisons with the exact solutions obtained from numerical results indicate that the proposed formula is able to provide an accurate approximation with an error of no more than ±2 %.

  5. Spatial and Seasonal Variation of Dissolved Organic Carbon (DOC) Concentrations in Irish Streams: Importance of Soil and Topography Characteristics

    Science.gov (United States)

    Liu, Wen; Xu, Xianli; McGoff, Nicola M.; Eaton, James M.; Leahy, Paul; Foley, Nelius; Kiely, Gerard

    2014-05-01

    Dissolved organic carbon (DOC) concentrations have increased in many sites in Europe and North America in recent decades. High DOC concentrations can damage the structure and functions of aquatic ecosystems by influencing water chemistry. This study investigated the spatial and seasonal variation of DOC concentrations in Irish streams across 55 sites at seven time occasions over 1 year (2006/2007). The DOC concentrations ranged from 0.9 to 25.9 mg/L with a mean value of 6.8 and a median value of 5.7 mg/L and varied significantly over the course of the year. The DOC concentrations from late winter (February: 5.2 ± 3.0 mg/L across 55 sites) and early spring (April: 4.5 ± 3.5 mg/L) had significantly lower DOC concentrations than autumn (October: mean 8.3 ± 5.6 mg/L) and early winter (December: 8.3 ± 5.1 mg/L). The DOC production sources (e.g., litterfall) or the accumulation of DOC over dry periods might be the driving factor of seasonal change in Irish stream DOC concentrations. Analysis of data using stepwise multiple linear regression techniques identified the topographic index (TI, an indication of saturation-excess runoff potential) and soil conditions (organic carbon content and soil drainage characteristics) as key factors in controlling DOC spatial variation in different seasons. The TI and soil carbon content (e.g., soil organic carbon; peat occurrence) are positively related to DOC concentrations, while well-drained soils are negatively related to DOC concentrations. The knowledge of spatial and seasonal variation of DOC concentrations in streams and their drivers are essential for optimum riverine water resources management.

  6. Post-failure characteristics of weathered soils in Korea: determination of rheological thresholds and debris flow mobility

    Science.gov (United States)

    Jeong, Sueng-Won; Fukuoka, Hiroshi; Im, Sang-June

    2013-04-01

    Landslides in Korea are mainly triggered by localized summer heavy rainfall. The water infiltration, wetting and fluidization process are the key roles in slope instability. Mechanically, a loss in soil strength of the soil at weakend layer takes place as a result of water infiltration. The transition from slides to flows can be defined by the variation in strength parameters. In the flowing stage with large volume of sediments, debris flow impact may be governed by the rheology of the failed mass. We performed the rheological tests using the ball-measuring and vane-inserted rheometer and examined a possible threshold of landslides on mudstone, weathered granitic and gneissic soils in the mountainous region of Korea. The materials examined exhibited the shear-thinning behavior, which is the viscosity decreases with increasing shear rates. There are positive relationships between liquidity index and rheological values (i.e., yield stress and viscosities). However, the difference in rheological properties is of significance for given shear rates. The effect of wall-slip in different geometries is emphasized. This work is also concerned with post-failure characteristics of rainfall-induced landslides that occur in Chuncheon, Miryang and Seoul debris flow occurrence in 2011. They are mainly composed of gneissic, sedimentary and gneissic weathered soils. The rheological properties is helpful to predict the mobilization of fine-laden debris flows. In the relationship between shear stress and shear rate, one of simplest rheological models, i.e., the ideal Bingham fluid model, is selected to examine the flow pattern and depositional features of debris flows. A comparison will be made for the debris flow occurence on weahtered soils in Korea.

  7. The influences of soil and nearby structures on dispersion characteristics of wave propagating along buried plastic pipes

    Science.gov (United States)

    Liu, Shuyong; Jiang, J.; Parr, Nicola

    2016-09-01

    Water loss in distribution systems is a global problem for the water industry and governments. According to the international water supply association (IWSA), as a result of leaks from distribution pipes, 20% to 30% of water is lost while in transit from treatment plants to consumers. Although governments have tried to push the water industry to reduce the water leaks, a lot of experts have pointed out that a wide use of plastic pipes instead of metal pipes in recent years has caused difficulties in the detection of leaks using current acoustic technology. Leaks from plastic pipes are much quieter than traditional metal pipes and comparing to metal pipes the plastic pipes have very different coupling characteristics with soil, water and surrounding structures, such as other pipes, road surface and building foundations. The dispersion characteristics of wave propagating along buried plastic pipes are investigated in this paper using finite element and boundary element based models. Both empty and water- filled pipes were considered. Influences from nearby pipes and building foundations were carefully studied. The results showed that soil condition and nearby structures have significant influences on the dispersion characteristics of wave propagating along buried plastic pipes.

  8. The soil water characteristic as new class of closed-form parametric expressions for the flow duration curve

    Science.gov (United States)

    Sadegh, M.; Vrugt, J. A.; Gupta, H. V.; Xu, C.

    2016-04-01

    The flow duration curve is a signature catchment characteristic that depicts graphically the relationship between the exceedance probability of streamflow and its magnitude. This curve is relatively easy to create and interpret, and is used widely for hydrologic analysis, water quality management, and the design of hydroelectric power plants (among others). Several mathematical expressions have been proposed to mimic the FDC. Yet, these efforts have not been particularly successful, in large part because available functions are not flexible enough to portray accurately the functional shape of the FDC for a large range of catchments and contrasting hydrologic behaviors. Here, we extend the work of Vrugt and Sadegh (2013) and introduce several commonly used models of the soil water characteristic as new class of closed-form parametric expressions for the flow duration curve. These soil water retention functions are relatively simple to use, contain between two to three parameters, and mimic closely the empirical FDCs of 430 catchments of the MOPEX data set. We then relate the calibrated parameter values of these models to physical and climatological characteristics of the watershed using multivariate linear regression analysis, and evaluate the regionalization potential of our proposed models against those of the literature. If quality of fit is of main importance then the 3-parameter van Genuchten model is preferred, whereas the 2-parameter lognormal, 3-parameter GEV and generalized Pareto models show greater promise for regionalization.

  9. Indication of Importance of Including Soil Microbial Characteristics into Biotope Valuation Method.

    Czech Academy of Sciences Publication Activity Database

    Trögl, J.; Pavlorková, Jana; Packová, P.; Seják, J.; Kuráň, P.; Kuráň, J.; Popelka, J.; Pacina, J.

    2016-01-01

    Roč. 8, č. 3 (2016), č. článku 253. ISSN 2071-1050 Institutional support: RVO:67985858 Keywords : biotope assessment * biotope valuation method * soil microbial communities Subject RIV: DJ - Water Pollution ; Quality Impact factor: 1.789, year: 2016

  10. Relationship of Aboveground Biomass Production Site Index and Soil Characteristics in a Loblolly Pine Stand

    Science.gov (United States)

    Minyi Zhou; Thomas J. Dean

    2004-01-01

    As a part of the continuing studies of the Cooperative Research in Sustainable Silviculture and Soil Productivity (CRiSSSP), 24 experimental plots in a loblolly pine (Pinus taeda L.) stand have recently been installed near Natchitoches, LA. The plots were uniformly assigned to 3 blocks based on topography (i.e., up slope, midslope, and down slope)....

  11. Characteristics of the flora of fallow lands on rendzina soils on the Twardowice Plateau (Silesian Upland

    Directory of Open Access Journals (Sweden)

    Beata Babczyńska-Sendek

    2012-12-01

    Full Text Available The paper presents the results of investigations on the flora of fallow lands on rendzina soils. The research was carried out in the area of the Twardowice Plateau (the Silesian Upland within 9 areas adjacent to xerothermic grasslands. The investigated flora consisted of 220 vascular plant species with the dominance of native taxa. Plants of xerothermic grasslands and thermophilous edges were the most numerous (32%. The dominance of Libanotis pyrenaica in 4 of the examined areas should be emphasized. The percentage of meadow species was also considerable (25%. Anthropophytes comprised 18% of the flora of fallow lands and archaeophytes prevailed among them (9%. Solidago canadensis, an invasive species, was the constant component of the investigated fallows and sometimes its coverage was remarkable. As a result of the high proportion of xerothermic and thermophilous plants, plants associated with dry soils and soils having an intermediate character between dry and fresh, as well as plants preferring slightly acidic to alkaline soils poor in nitrogen compounds predominated in the investigated fallows. Perennial plants prevailed (65% in the studied flora and slightly more than half of the species reproduced only by seeds. Competitive plant species (C strategists had the highest proportion (39% and species with intermediate strategies CSR, CR and CS were also numerous. The investigations have shown that there are favourable conditions for settling and growth of many xerothermic species in the investigated fallow lands. Moreover, the neighbouring grasslands are the seed source for these areas.

  12. Physical and Chemical Characteristics of Ash-influenced Soils of Inland Northwest Forests

    Science.gov (United States)

    P. A. McDaniel; M. A. Wilson

    2007-01-01

    Holocene ash from the cataclysmic eruption of Mount Mazama (now Crater Lake) in southeastern Oregon is a major component of many forest soils that lie to the east of Cascade Mountains in the Pacific Northwest region. The relatively high productivity of the region’s ecosystems is closely linked to this volcanic ash component. This paper reports on the ecologically...

  13. The characteristics and suitability of the soils of some major cocoa ...

    African Journals Online (AJOL)

    However, the values of potential productivity index (13.41 - 45) suggested that most of the mapping units will be marginally suitable (S3) for cocoa production with adequate application of appropriate fertilizers and suitable soil management practices. This will require a carefully designed fertilizer trial to ascertain the optima ...

  14. Effect on stone lines on soil chemical characteristics under continuous sorghum cropping in semiarid Burkina Faso

    NARCIS (Netherlands)

    Zougmore, R.; Gnankambary, Z.; Guillobez, L.S.; Stroosnijder, L.

    2002-01-01

    In the semiarid Sahel, farmers commonly lay stone lines in fields to disperse runoff. This study was conducted in northern Burkina Faso to assess the chemical fertility of soil under a permanent, non-fertilised sorghum crop, which is the main production system in this area, 5 years after laying

  15. Immediate impact of the flood (Bohemia, August 2002) on selected soil characteristics

    Czech Academy of Sciences Publication Activity Database

    Elhottová, Dana; Krištůfek, Václav; Tříska, Jan; Chrastný, V.; Uhlířová, Eva; Kalčík, Jiří; Picek, T.

    2006-01-01

    Roč. 173, č. 1-4, (2006), s. 177-193 ISSN 0049-6979 Institutional research plan: CEZ:AV0Z6066911; CEZ:AV0Z6087904; CEZ:AV0Z60870520 Keywords : flood on soil * hazardous elements * organic persistent compounds Subject RIV: EH - Ecology, Behaviour Impact factor: 1.205, year: 2006

  16. Changes in microbial community characteristics and soil organic matter with nitrogen additions in two tropical forests

    Science.gov (United States)

    Daniela F. Cusack; Whendee L. Silver; Margaret S. Torn; Sarah D. Burton; Mary K. Firestone

    2011-01-01

    Microbial communities and their associated enzyme activities affect the amount and chemical quality of carbon (C) in soils. Increasing nitrogen (N) deposition, particularly in N-rich tropical forests, is likely to change the composition and behavior of microbial communities and feed back on ecosystem structure and function. This study presents a novel assessment of...

  17. [Effects of supplemental irrigation based on measuring soil water content on wheat photosynthetic characteristics and dry matter accumulation and allocation].

    Science.gov (United States)

    Wang, Hong-guang; Yu, Zhen-wen; Zhang, Yong-li; Wang, Dong; Shi, Yu; Xu, Zhen-zhu

    2011-10-01

    Taking high-yielding winter wheat cultivar Jimai 22 as test material, a field experiment was conducted to study the effects of supplemental irrigation based on measuring soil water content on the wheat photosynthetic characteristics and dry matter accumulation and allocation. Six treatments were installed, i. e., W1 (soil relative water content was 65% at jointing stage and was 70% at anthesis), DW1 (soil relative water content was 65% 10 d after jointing and was 70% at anthesis), W2 (soil relative water content was 75% at jointing and was 70% at anthesis), DW2 (soil relative water content was 75% 10 d after jointing and was 70% at anthesis), W3 (soil relative water content was 80% at jointing stage and was 70% at anthesis), and DW3 (soil relative water content was 80% 10 d after jointing and was 70% at anthesis). In treatments W2 and DW2, the flag leaf photosynthetic rate (P(n)) and phi(PS II) at late filling stage were higher than those in treatments W3 and DW3, respectively, the dry matter accumulation amount at anthesis and maturity stage and the allocation of accumulated dry matter at pre-anthesis to grain were significantly higher than those in treatments W1 and DW1, and the water use efficiency (WUE) and irrigation production efficiency (IPE) were significantly higher than those in W3 and DW3. Under the same irrigation levels, the flag leaf P(n), and phi(PS II) at late filling stage were higher in treatments DW2 and DW3 than in W2 and W3, respectively, and the dry matter accumulation amount at anthesis and its allocation to grain were lower whereas the dry matter accumulation amount after anthesis, the grain yield, WUE, and IPE were higher in DW2 and DW3 than in W2 and W3. Under our experimental condition, DW2 could be the optimal irrigation pattern of high-yielding with high WUE.

  18. [Characteristics of soil water infiltration in sub-alpine dark coniferous ecosystem of upper reaches of Yangtze River].

    Science.gov (United States)

    Yu, Xinxiao; Zhao, Yutao; Zhang, Zhiqiang; Cheng, Genwei

    2003-01-01

    Dark coniferous forest is the predominant type of vegetation in the upper reaches of Yangtze River. Difference among different types of soil exists. The sand content of soil is higher and the soil texture is coarser in the early stage of forest succession. The sand content of soil decreases with the advancement of the forest succession while that of soil in Abies fabri over-mature forest is the lowest. In slope wash soil, the sand content of soil decreases with the increasing soil depth. The soil porosity and soil water-holding capacity increases and soil bulk density decreases with the advancement of forest succession and decrease of soil depth. The deeper soil depth or the smaller soil water content are, the smaller the unsaturated hydraulic conductivity of soil measured by CGA method. Moreover, the correlation of soil water content with unsaturated hydraulic conductivity of soil can be simulated by an exponential function. The saturated hydraulic conductivity of soil decreases exponentially with the increasing soil depth. The time to attain the stable infiltration rate is different among different soil depth, while the deeper the soil depth is, the longer the time needs. The variation in soil texture, soil physical properties and the high infiltration rate of soil there implicated that there are scarce surface runoff, but abundant in subsurface flow, return flow and seepage, which is the result of regulation by dark coniferous forest on hydrological processes.

  19. Characteristics of woodland rhizobial populations from surface- and deep-soil environments of the sonoran desert.

    Science.gov (United States)

    Waldon, H B; Jenkins, M B; Virginia, R A; Harding, E E

    1989-12-01

    A collection of 74 rhizobial isolates recovered from nodules of the desert woody legumes Prosopis glandulosa, Psorothamnus spinosus, and Acacia constricta were characterized by using 61 nutritional and biochemical tests. We compared isolates from A. constricta and Prosopis glandulosa and tested the hypothesis that the rhizobia from a deep-phreatic rooting zone of a Prosopis woodland in the Sonoran Desert of southern California were phenetically distinct from rhizobia from surface soils. Cluster analysis identified four major homogeneous groups. The first phenon contained slow-growing (SG) Prosopis rhizobia from surface and deep-phreatic-soil environments. These isolates grew poorly on most of the media used in the study, probably because of their requirement for a high medium pH. The second group of isolates primarily contained SG Prosopis rhizobia from the deep-phreatic rooting environment and included two fast-growing (FG) Psorothamnus rhizobia. These isolates were nutritionally versatile and grew over a broad pH range. The third major phenon was composed mainly of FG Prosopis rhizobia from surface and dry subsurface soils. While these isolates used a restricted range of carbohydrates (including sucrose) as sole carbon sources, they showed better growth on a range of organic acids as sole carbon sources and amino acids as sole carbon and nitrogen sources than did other isolates in the study. They grew better at 36 degrees C than at 26 degrees C. The FG Acacia rhizobia from surface-soil environments formed a final major phenon that was distinct from the Prosopis isolates. They produced very high absorbance readings on all of the carbohydrates tested except sucrose, grew poorly on many of the other substrates tested, and preferred a 36 to a 26 degrees C incubation temperature. The surface populations of Prosopis rhizobia required a higher pH for growth and, under the conditions used in this study, were less tolerant of low solute potential and high growth

  20. Diversity and Symbiotic Characteristics of Cowpea Bradyrhizobium Strains in Ghanaian Soils

    International Nuclear Information System (INIS)

    Fening, Joseph Opoku

    1999-08-01

    This study reports investigation of the biodiversity of bradyrhizobia isolates that nodulate cowpea in Ghanaian soils. As a prelude, some components of nitrogen fixation of cowpea in the various soils were examined through: (1) assessment of the natural nodulation of 45 cowpea cultivars in 20 soils sampled from 5 ecozones (coastal savanna, tain forest, semi deciduous forest, forest savanna transition and guinea savanna), (2) determination of the numbers of bradyrhizobial isolates in the soils and (3) determination of the response of cowpea to nitrogen fertilization. The results of the ability of 45 cowpea cultivars to nodulate naturally in different soil types showed large variability among the cultivars. Counts of the indigenous bradyrhizobia population in the soils showed that most of the soils in Ghana harbour large populations of bradyrhizobia (in the range of 0.6 x 10 to 31 x 10 3 ) capable of nodulating cowpea. Response of cowpea to nitrogen fertilizer differed in the different soils. In general all the cultivars showed significant responses to increasing levels of nitrogen, an indication that nitrogen fixation was not supplying the plants with all the external nitrogen required for maximum yield. A combination of morpho-physiological and molecular analysis was used to assess the diversity of the bradyrhizobia isolates. A total of 100 isolates were assessed. The results of the morpho physiological analysis indicated that cowpea is nodulated by both fast and slow growing rhizobia. The results also showed that the isolates were versatile and could survive under different soil conditions particularly acidity and salt stress. A cross inoculation study of the isolates with nine legume species produced seven major groupings with 28 subgroups based on distinct nodulation patterns. Results of the serology (ELISA) assay indicated that only a small fraction of the isolates reacted strongly with antisera of each other. The greater proportion showed no cross reactivity

  1. [Characteristics of 'salt island' and 'fertile island' for Tamarix chinensis and soil carbon, nitrogen and phosphorus ecological stoichiometry in saline-alkali land].

    Science.gov (United States)

    Zhang, Li-hua; Chen, Xiao-bing

    2015-03-01

    To clarify the nutrient characteristics of 'salt island' and 'fertile island' effects in saline-alkali soil, the native Tamarix chinensis of the Yellow River Delta (YRD) was selected to measure its soil pH, electrical conductivity (EC), organic carbon (SOC), total nitrogen (N), total phosphorus (P) and their stoichiometry characteristics at different soil depths. The results showed that soil pH and EC increased with the increasing soil depth. Soil EC and P in the 0-20 cm layer decreased and increased from canopied area to interspace, respectively. SOC, N, N/P and C/P in the 20-40 cm soil layer decreased, and C/N increased from the shrub center to interspace. SOC and N contents between island and interspace both decreased but P content decreased firstly and then increased with the increasing soil depth. Soil pH correlated positively with EC. In addition, pH and EC correlated negatively with C, N, P contents and their ecological stoichiometry.

  2. [Seasonal characteristics of soil respiration and affecting factors under typical vegetations in the water-wind erosion crisscross region of the Loess Plateau].

    Science.gov (United States)

    Xie, Hui-Hui; Fan, Jun; Qi, Li-Bin; Hao, Ming-De

    2010-12-01

    By the soil respiration system, the characteristics of soil respiration were investigated to explore the correlations between soil respiration and soil temperature, soil water and soil nutrient under different land use patterns in the water-wind erosion crisscross region of the Loess Plateau. The results indicated that the seasonal changing characteristics of soil respiration were distinguished significantly among different vegetations, and soil water content and temperature were the main influencing factors. Soil respiration seasonal changing ranges, such as bare land, crop land, Medicago sativa land, Caragana korshinskii land, abandoned wild grass land, Stipa bungeana land, wild grass land, degraded Medicago sativa land, sloping Medicago sativa land, sloping abandoned wild grass land, sloping crop land and terraced crop land, were 0.32-0.82, 0.41-2.83, 0.74-2.81, 0.76-3.07, 0.67-2.79, 0.51-2.12, 0.56-2.05, 0.59-1.66, 0.42-2.09, 0.31-1.86, 0.32-1.93 and 0.41-3.17 micromol x (m2 x s)(-1). Comparing seasonal changing magnitudes of soil respiration, crop land was the biggest (167% - 203%), abandoned wild grass land (117% -154%), Caragana korshinskii land (134%), Stipa bungeana land (129%), Medicago sativa land (119%-120%) and bare land (94%) followed crop land. The smallest was degraded Medicago sativa land (92%). Bare land and degraded Medicago sativa land had small seasonal variation during the study period. Monthly average values of soil carbon flux (soil respiration) of Medicago sativa land and Caragana korshinskii land were maximal, but the maximum values under crop land were observed in July and August. Besides Q10 of crop land was also maximal, which reached 1.86. There were significant correlations between soil respiration and soil organic matter and available K. Moreover, soil respiration was affected by soil organic matter and total nitrogen in July and August when the water and heat condition were plentiful, but soil ammonium nitrogen had negative impact

  3. Soil Characteristics and Lodgepole Pine (Pinus contorta var. latifolia Performance Two Decades after Disk Trenching of Unburned and Broadcast-Burned Plots in Subboreal British Columbia

    Directory of Open Access Journals (Sweden)

    Jacob O. Boateng

    2011-01-01

    Full Text Available We examined the effects of low-impact broadcast-burning and disk-trenching planting position (control, hinge, trench on soil characteristics and lodgepole pine foliar nutrition and growth over two decades at a subboreal site in British Columbia, Canada. Broadcast burning had virtually no effect on either the bulk density or chemical properties of soil. In contrast, significant reductions in soil bulk density and increases in soil nutrient availability persisted for 20 years in hinge position soils relative to undisturbed (control soil between trenches. These effects on bulk density and nutrient availability are associated with significant differences in pine size by year 6. Burning and planting positions interacted significantly in their effect on pine height, diameter, and stem volume for at least 19 years. Pine survival was high regardless of burning or planting position. Neither broadcast burning nor planting position significantly affected lodgepole pine foliar nutrient status in this study.

  4. Organic carbon characteristics in density fractions of soils with contrasting mineralogies

    Science.gov (United States)

    Yeasmin, Sabina; Singh, Balwant; Johnston, Cliff T.; Sparks, Donald L.

    2017-12-01

    This study was aimed to evaluate the role of minerals in the preservation of organic carbon (OC) in different soil types. Sequential density fractionation was done to isolate particulate organic matter (POM, 2.6 g cm-3) from four soils, i.e., a Ferralsol, a Luvisol, a Vertisol and a Solonetz. Organic matter (OM) in the density fractions was characterised using diffuse reflectance Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy and mass spectroscopy in the original states (i.e., without any chemical pre-treatment), and after 6% sodium hypochlorite (NaOCl) and 10% hydrofluoric acid (HF) treatments. The NaOCl oxidation resistant fraction was considered as a relatively stable pool of OC and the HF soluble fraction was presumed as the mineral bound OC. Phyllosilicate-dominated soils, i.e., Vertisol, Luvisol and Solonetz, contained a greater proportion of POM than Fe and Al oxide-dominated Ferralsol. Wider C:N ratio and lower δ13C and δ15N in POM suggest the dominance of labile OC in this fraction and this was also supported by a greater proportion of NaOCl oxidised OC in the same fraction that was enriched with aliphatic C. The sequential density fractionation method effectively isolated OM into three distinct groups in the soils: (i) OM associated with Fe and Al oxides (>1.8 g cm-3 in the Ferralsol); (ii) OM associated with phyllosilicates (1.8-2.6 g cm-3) and (iii) OM associated with quartz and feldspar (>2.6 g cm-3) in the other three soils. Greater oxidation resistance, and more dissolution of OC during the HF treatment in the Fe and Al oxides dominated fractions suggest a greater potential of these minerals to protect OC from oxidative degradation as compared to the phyllosilicates, and quartz and feldspar matrices. OM associated with Fe and Al oxides was predominantly aromatic and carboxylate C. Decreased C:N ratio in the NaOCl oxidation resistant OM and HF soluble OM of phyllosilicates, and quartz and feldspars dominant fractions

  5. Characteristic Changes in Soil CO2 Efflux Resulting from Physical Disturbance

    Science.gov (United States)

    Klapstein, S.; Risk, D. A.

    2009-12-01

    Subsoil organic matter (SOM) stability has long thought to be governed primarily by temperature and microbial dynamics with very little emphasis being placed on the contribution of physical factors to microbial metabolism. In nature, rain, invertebrate and animal action, soil moisture, mechanical disturbance, freeze-thaw, and other processes may generate a response from the microbial community due to the movement of substrate and microbes, changes in oxygen availability, solubilization, and mechanical weathering. Understanding how physical factors affect both labile and recalcitrant carbon is important for predicting future changes in the soil carbon pool, a pool that contains twice the amount of carbon than that of the atmosphere. Here, paired lab-field experiments explore the effect of changes in the physical environment and respiration of SOM in mineral soil from an 80-year old red spruce forest stand in Nova Scotia, Canada. The factors tested were substrate transport, physical abrasion, wetting, and change in oxygen availability and were carried out using the following respective disturbance methodologies; electrokinetics, mixing and vibration, wetting, and air sparging. Briefly, electrokinetics has been used in the bioremediation field and fundamentally relies on electric fields to move charged particles and microbes thereby testing the island effect proposed recently by some researchers. Physical abrasion breaks down soil aggregates and abrades SOM directly, wetting causes dissolution of SOM, and air sparging injects O2-rich air into potentially depleted regions. The response of each disturbance factor was measured by Continuous Timeseries-Forced Diffusion (CT-FD), a continuous real time CO2 emissions monitoring tool that provides high frequency data which helped capture the unique temporal properties of each disturbance. Additional supporting geochemistry and gas transport modeling experiments were carried out to help quantify and validate the impact of each

  6. Validation of Transfer Functions Predicting Cd and Pb Free Metal Ion Activity in Soil Solution as a Function of Soil Characteristics and Reactive Metal Content

    NARCIS (Netherlands)

    Pampura, T.; Groenenberg, J.E.; Lofts, S.; Priputina, I.

    2007-01-01

    According to recent insight, the toxicity of metals in soils is better related to the free metal ion (FMI) activity in the soil solution than to the total metal concentration in soil. However, the determination of FMI activities in soil solution is a difficult and time-consuming task. An alternative

  7. Undesirable Behaviors Elementary School Classroom Teachers Encounter in the Classroom and Their Reasons

    Directory of Open Access Journals (Sweden)

    E.G. Balcik

    2011-12-01

    Full Text Available The present study aims to determine how often elementary school teachers encounter undesirable behaviors in the classroom and what their thoughts regarding possible reasons of these behaviors are. The teachers’ opininon about the prevalence of these behaviors and their possible reasons were evaluated according to gender, marital status, level of class being taught, size of class being taught and it was tried to be determined if there were significant differences between variables. The measurement tool was applied to a total of 54 teachers at 5 schools in Gölcük district of the Kocaeli province. The data collection tool is composed of three sections. The first section is for establishing teachers’ personal information. In this study, as a data collection tool, a questionnaire was used. When preparing questions for the questionnaire, following the examination of resources available, the questionnaire prepared by Aksoy (1999 and used in the thesis study entitled “Classroom Management and Student Discipline in Elementary Schools of Ankara” and also used in the thesis study by Boyraz (2007 entitled “Discipline Problems that Candidate Teachers Servicing at Elementary Schools Encounter in the Classroom” was employed. Although the validity and reliability of the questionnaire was tested by Aksoy (1999 and Boyraz (2007, the reliability study for the questionnaire was retested and found to be 0,9. The questionnaire include 42 items. 19 of them are related to the reasons of undesirable behaviors observed in the classroom and 23 of them are related to undesirable behaviors observed in the classroom.

  8. A survey on the presence of undesirable botanical substances in feed in the European Union

    Directory of Open Access Journals (Sweden)

    van Raamsdonk LWD.

    2009-01-01

    Full Text Available Directive 2002/32/EC of the European Parliament and of the Council of 7 May 2002 on undesirable substances in animal feed lists a range of substances from botanical origin (weed seeds and additionally some chemical compounds directly originating from specific weeds. In order to examine the actual status of enforcement and of the present occurrence of these botanical substances, a survey was carried out. A questionnaire was sent to 103 laboratories, including official control labs from all member states of the European Union. The results, indicating the frequency of occurrence as far as reported, are compared to the publications of the EU Rapid Alert System for Food and Feed (RASFF. A total of 44 questionnaires was returned (42.7% from 22 member states. Ten member states predominantly from north-western Europe appeared to have an active monitoring of botanical undesirable substances. The questionnaire results did not indicate that the other member states enforce this part of Directive 2002/32/EC. Reports on the frequency of occurrence include: a few to 25-50% of the samples contain traces of ergot (8 member states, a few to 24% contain at least some traces of thorn apple (6 member states, zero to 17% contain some castor oil plant seeds (3 member states, zero to a few samples contain Crotalaria seeds (3 member states, and zero to 6% contain traces of Sareptian mustard (4 member states. One member state conducted extra surveillance since several cases of animal intoxications have been reported. In some cases a coincidence with undesirable botanical substances was found.

  9. [Characteristics of mercury exchange flux between soil and atmosphere under the snow retention and snow melting control].

    Science.gov (United States)

    Zhang, Gang; Wang, Ning; Ai, Jian-Chao; Zhang, Lei; Yang, Jing; Liu, Zi-Qi

    2013-02-01

    Jiapigou gold mine, located in the upper Songhua River, was once the largest mine in China due to gold output, where gold extraction with algamation was widely applied to extract gold resulting in severe mercury pollution to ambient environmental medium. In order to study the characteristics of mercury exchange flux between soil (snow) and atmosphere under the snow retention and snow melting control, sampling sites were selected in equal distances along the slope which is situated in the typical hill-valley terrain unit. Mercury exchange flux between soil (snow) and atmosphere was determined with the method of dynamic flux chamber and in all sampling sites the atmosphere concentration from 0 to 150 cm near to the earth in the vertical direction was measured. Furthermore, the impact factors including synchronous meteorology, the surface characteristics under the snow retention and snow melting control and the mercury concentration in vertical direction were also investigated. The results are as follows: During the period of snow retention and melting the air mercury tends to gather towards valley bottom along the slope and an obvious deposit tendency process was found from air to the earth's surface under the control of thermal inversion due to the underlying surface of cold source (snow surface). However, during the period of snow melting, mercury exchange flux between the soil and atmosphere on the surface of the earth with the snow being melted demonstrates alternative deposit and release processes. As for the earth with snow covered, the deposit level of mercury exchange flux between soil and atmosphere is lower than that during the period of snow retention. The relationship between mercury exchange flux and impact factors shows that in snow retention there is a remarkable negative linear correlation between mercury exchange flux and air mercury concentration as well as between the former and the air temperature. In addition, in snow melting mercury exchange

  10. Sorption Characteristics of 137Cs and 90Sr into Rembang and Sumedang Soils

    Directory of Open Access Journals (Sweden)

    Budi Setiawan

    2016-12-01

    Full Text Available In order to understand the sorption behavior of 137Cs and 90Sr into soil sample from Rembang and Subang, it is important to estimate the effect of contact time, ionic strength and concentration of metal ion in the solution. For this reason, the interaction of 137Cs and 90Sr with soil sample has been examined. The study performed at trace concentration (~10-8 M of CsCl and SrCl2, and batch method was used. NaCl has been selected as a representative of the ionic strength with 0.1; 0.5 and 1.0 M concentrations. Concentration of 10-8~10-4 M CsCl and SrCl2 were used for study the effect of Cs and Sr concentrations in solution. Apparent distribution coefficient was used to predict the sorption behavior. The sorption equilibrium of 137Cs and 90Sr into soil was attained after 5 days contacted with Kd value around 3300-4200 mL/g, where Kd was defined as the ratio of number of radionuclide activity absorbed in solid phase per-unit mass to the number of radionuclide activity remains is solution per-unit volume. Presence of NaCl as background salt in the solution affected Kd values due to competition among metal ions into soil samples. Increase of Cs or Sr concentration in solution made Kd value decreased drastically. This information is expected could provide an important input for the planning and design of radioactive waste disposal system in Java Island in the future.

  11. Spatial variability in grape yield and quality influenced by soil and crop nutrition characteristics

    OpenAIRE

    Arnó Satorra, Jaume; Rosell Polo, Joan Ramon; Blanco Ortiz, Ricardo; Ramos Martín, Ma. C. (Ma. Concepción); Martínez Casasnovas, José Antonio

    2012-01-01

    Knowledge of spatial variability of soil fertility and plant nutrition is critical for planning and implementing site-specific vineyard management. To better understand the key drivers behind vineyard variability, yield mapping from 2002 to 2005 and 2007 (the monitor broke down in 2006) was used to identify zones of different productive potential in a Pinot Noir field located in Raimat (Lleida, Spain). Simultaneously, the vineyard field was sampled in 2002, 2003 and 2007, applying three diffe...

  12. Toxicities of TNT and RDX to the Earthworm Eisenia fetida in Five Soils with Contrasting Characteristics

    Science.gov (United States)

    2013-05-01

    light. Earthworm colonies were fed biweekly with alfalfa food consisting of dehydrated alfalfa pellets (27% fiber, 17% protein, 1.5% fat; Ohio Blenders...of PA; York, PA). Before use, the alfalfa pellets were hydrated, fermented for at least 14 days, air-dried, and ground to a course powder. Earthworm...assays, a 2 g bolus of prepared alfalfa food was added to each jar, moistened with an atomizer, and covered with soil from within the jar. Clear

  13. Influence of Biochar Amendment on Soil Water Characteristics and Crop Growth Enhancement Under Salinity Stress

    OpenAIRE

    Gamareldawla H.D

    2017-01-01

    Salinity is an important environmental constraint to crop productivity in arid and semi-arid regions of the world. Most crop plants, including tomato (Lycopersicon esculentum Mill), are sensitive to salinity throughout the ontogeny of the plant. Biochar was used in the present study to improve the available water content (AWC), growth, yield and irrigation water use efficiency of tomato plant under saline soil condition. The biochar was applied at the rates of, 0%, 2% and 4% w/w and expressed...

  14. Influence of Biochar Amendment on Soil Water Characteristics and Crop Growth Enhancement Under Salinity Stress

    OpenAIRE

    Agbna , Gamareldawla ,; Ali1 , Abubaker ,; Bashir , Amir ,; Eltoum , Farid; Hassan , Mohamed ,

    2017-01-01

    International audience; Salinity is an important environmental constraint to crop productivity in arid and semi-arid regions of the world. Most crop plants, including tomato (Lycopersicon esculentum Mill), are sensitive to salinity throughout the ontogeny of the plant. Biochar was used in the present study to improve the available water content (AWC), growth, yield and irrigation water use efficiency of tomato plant under saline soil condition. The biochar was applied at the rates of, 0%, 2% ...

  15. Impact of soil sorption characteristics and bedrock composition on phosphorus concentrations in two Bohemian Forest lakes

    Czech Academy of Sciences Publication Activity Database

    Kaňa, Jiří; Kopáček, Jiří

    2006-01-01

    Roč. 173, 1-4 (2006), s. 243-259 ISSN 0049-6979 R&D Projects: GA ČR(CZ) GA206/03/1583; GA AV ČR(CZ) 1QS600170504 Grant - others:EC(XE) GOCE-CT-2003-505540; MSM(CZ) 6007665801 Institutional research plan: CEZ:AV0Z60170517 Keywords : acidification * aluminium * forest soils Subject RIV: DJ - Water Pollution ; Quality Impact factor: 1.205, year: 2006

  16. Improvement of Soil Biology Characteristics at Paddy Field by System of Rice Intensification

    OpenAIRE

    Widyatmani Sih Dewi

    2015-01-01

    The aim of the research was to test the System of Rice Intensification (SRI) method in improving the biological properties of paddy soil. The indicators of improvement were measured by the number of earthworm feces (cast), and the population of some microbial and nutrient content in the cast. The experiments were performed by comparing the three methods, namely: (1) SRI, (2) semi-conventional, and (3) conventional, using Randomized Completely Block Design. Each treatment was repeated nine tim...

  17. Environmental efficiency evaluation of china based on a kind of congestion and undesirable output coefficient

    Directory of Open Access Journals (Sweden)

    Song Malin

    2015-01-01

    Full Text Available The production “congestion” phenomenon is widespread in reality although few models nowadays consider its influences. In this study, production congestion is introduced into an environmental efficiency evaluation model and a new data envelopment analysis model that considers both production congestion and undesirable output is established so as to measure environmental efficiency evaluation effectively. On this basis, we divide technological change into productive technological change and energy-savings emission reduction technological change to establish their influences on the congestion phenomenon. The results show that productive technological change cannot relieve the degree of congestion while green technology change that stimulates environmental efficiency improvement can greatly alleviate situations of congestion.

  18. Guidelines used in Japan to prevent the contamination of feed products with undesirable substances

    Directory of Open Access Journals (Sweden)

    Katsuaki Sugiura

    2011-01-01

    Full Text Available As Japan depends on imports for most ingredients used to manufacture feed products, close co-operation is indispensable between importers and manufacturers of feed and feed ingredients to effectively mitigate the risk associated with feed safety. Guidelines were issued by the Ministry of Agriculture, Forestry and Fisheries (MAFF in March 2008 to prevent feed products from being contaminated with undesirable substances. These guidelines identify the responsibilities of feed ingredient importers, feed manufacturers and distributors, as well as the roles of the MAFF and the Food and Agricultural Materials Inspection Centre.

  19. Distinguishing Technical Inefficiency from Desirable and Undesirable Congestion with an Application to Regional Industries in China

    Directory of Open Access Journals (Sweden)

    Jun Wang

    2014-12-01

    Full Text Available Congestion is an important issue that requires the efficiency of decision-making units (DMUs. We first classify conventional congestion into congestion (newly defined and technical inefficiency, based on prior research and real applications. Modified definitions and mathematical expression of congestion, managerial inefficiency, and technical inefficiency are proposed to better illustrate the differences between them. Several modified models are provided to identify and recognize those types of inefficiencies and congestion. We then extend the model by considering the desirable and undesirable types of congestion simultaneously. The proposed approach is applied and verified by identifying resource congestion and environmental inefficiencies in China’s economic development.

  20. USING OF THE MATHEMATICAL STATISTICS METHODS FOR THE CHARACTERISTIC OF THE ELEMENTAL CONTAMINATION URBAN ECOSYSTEMS SOILS BY THE HEAVY METALS

    Directory of Open Access Journals (Sweden)

    YAKOVYSHYNA T. F.

    2017-03-01

    Full Text Available Summary. Raising of problem. Sustainable development of the urban ecosystems, taking into account the provision of ecological safety standards for the human life within the city and the rational use and restoration of the resource potential of the territory, requires the search for effective methods of the characteristic of the ecological situation. In the conditions of the progressive pressure to the environment, the leading role belongs to the mathematical statistics methods, as a tool that allows us to examine and analyze in detail ecological systems of the various complexity. Of all the environmental abiotic components, soils have been given the least attention, which is due, firstly, to the ambiguous characteristic of the environmental situation according to the total content of the contaminant, and secondly, to the problem of choice its additional forms for the statistical analysis. Purpose. Substantial using of the mathematical statistics methods in the ecomonitoring system along with the generally accepted for the characterization of the elemental soil contamination of the urban ecosystem by the heavy metals, by determining the statistical characteristics and establishing relationships between the total content, potentially available and available forms by the example of Zn contamination in the Dnieper. The total content, potentially available and available forms have been used to determine the elemental Zn contamination. An array of the content data of the studied Zn forms has been obtained in the network of ecological monitoring of soils of the Dnieper urban ecosystem: grid (2 km × 2 km, key sampling sites – 65. In the selected samples, the Zn total content yas been determined by the atomic absorption method after acidizing the soil, its potentially available forms in the extraction of 1 H HCl, and the available forms in AAB (pH 4.8 by standard methods. The mathematical statistics methods and the application package Microsoft Excel

  1. Effect of long-term application of oil refinery wastewater on soil health with special reference to microbiological characteristics

    Energy Technology Data Exchange (ETDEWEB)

    Hayat, S.; Azam, Z.M.; Ahmad, A.; Inam, A.; Samiullah [Aligarh Muslim University (India). Department of Botany; Ahmad, I. [Aligarh Muslim University (India). R.A.K. Institute of Agricultural Sciences, Department of Agricultural Microbiology

    2002-09-01

    The ground water (GW), treated wastewater (TW) and the soil at the agricultural farm in the premises of the Mathura Oil Refinery have been monitored for various physico-chemical characteristics, over the last 12 years (1987-1998). It was noted that the heavy metal content in the soil, repeatedly irrigated with TW, was increasing because the wastewater itself was a better source of these metals than GW. However, the level of these metals, both in the wastewater and the soil, was very much below the permissible limits. The quantitative analysis of various functional groups of microorganism and their interaction with metals revealed that the viable count of aerobic heterotrophs, asymbiotic nitrogen fixers, actinomycetes and fungi were in the ranges of 2.6x10{sup 6}-7.2x10{sup 7}, 5.0x10{sup 4}-6.8x10{sup 5}, 2.0x10{sup 4}-2.8x10{sup 5} and 2.5x10{sup 4}-7.5x10{sup 5}, respectively. The presence of Rhizobium spp. in the soil was shown by the nodulation in the leguminous crops cultivated in the experimental field. The significant viable counts of above functional groups of bacteria on each heavy metal supplemented plate indicated that these populations could tolerate high levels ({>=}200{sup {mu}}g/ml) of metal. Among them, nitrogen fixers and aerobic heterotrophs (largely, Gram-negative) had a higher degree of resistance to heavy metals than actinomycetes. Similarly, the strains of Rhizobium, isolated from the experimental field, showed a higher degree of resistance under in vitro conditions and the minimum inhibitory concentration (MIC) was in the range of 50-800{sup {mu}}g/ml, determined by a plate dilution method. It may, therefore, be deduced that 12 years repeated application of treated wastewater had not significantly changed the microbial dynamics of the soil and possibly the bacteria had adapted to the changed soil environment by developing various levels of metals resistance. (author)

  2. Effects of root pruning on the growth and rhizosphere soil characteristics of short-rotation closed-canopy poplar

    Energy Technology Data Exchange (ETDEWEB)

    Du, Z. Y.; Xing, S. J.; Ma, B. Y.; Liu, F. C.; Ma, H. L.; Wang, Q. H.

    2012-11-01

    When poplar trees planted at a high density are canopy-closed in plantation after 4-5 years of growth, the roots of adjacent trees will inevitably intermingle together, which possibly restricts the nutrient uptake by root system. Root pruning might stimulate the emergence of fine roots and benefit the tree growth of short-rotation poplar at the stage of canopy closing. The aim of this study is to evaluate the effects of root pruning on DBH (diameter at breast height, 1.3 m), tree height, nutrients (N, P and K) and hormones (indoleacetic acid and cytokinin) in poplar leaves, gas exchange variables (photosynthetic rate and stomatal conductance), and rhizosphere soil characteristics. Field experiment was carried out with four-yearold poplar (Populus × euramericana cv. ‘Neva’) planted in a fluvo-aquic loam soil in Shandong province, China in early April, 2008. Three root pruning treatments (severe, moderate and light degree) were conducted at the distances of 6, 8 and 10 times DBH on both inter-row sides of the trees to the depth of 30 cm, respectively. The results showed that the growth performance was obtained in the following order of treatments: moderate > light = control > severe. In the rhizophere soil, moderate and light pruning increased the microbial populations, enzymatic activities, and the concentrations of available N, P, K and organic matter. Generally, root pruning to improve tree growth and rhizosphere soil fertility can be recommended in canopy-closed poplar plantation. The appropriate selection of root pruning intensity is a pivotal factor for the effectiveness of this technique. (Author) 35 refs.

  3. Attributes for NHDPlus catchments (Version 1.1) for the conterminous United States: STATSGO soil characteristics

    Science.gov (United States)

    Wieczorek, Michael; LaMotte, Andrew E.

    2010-01-01

    This data set represents estimated soil variables compiled for every catchment of NHDPlus for the conterminous United States. The variables included are cation exchange capacity, percent calcium carbonate, slope, water-table depth, soil thickness, hydrologic soil group, soil erodibility (k-factor), permeability, average water capacity, bulk density, percent organic material, percent clay, percent sand, and percent silt. The source data set is the State Soil ( STATSGO ) Geographic Database (Wolock, 1997). The NHDPlus Version 1.1 is an integrated suite of application-ready geospatial datasets that incorporates many of the best features of the National Hydrography Dataset (NHD) and the National Elevation Dataset (NED). The NHDPlus includes a stream network (based on the 1:100,00-scale NHD), improved networking, naming, and value-added attributes (VAAs). NHDPlus also includes elevation-derived catchments (drainage areas) produced using a drainage enforcement technique first widely used in New England, and thus referred to as "the New England Method." This technique involves "burning in" the 1:100,000-scale NHD and when available building "walls" using the National Watershed Boundary Dataset (WBD). The resulting modified digital elevation model (HydroDEM) is used to produce hydrologic derivatives that agree with the NHD and WBD. Over the past two years, an interdisciplinary team from the U.S. Geological Survey (USGS), and the U.S. Environmental Protection Agency (USEPA), and contractors, found that this method produces the best quality NHD catchments using an automated process (USEPA, 2007). The NHDPlus dataset is organized by 18 Production Units that cover the conterminous United States. The NHDPlus version 1.1 data are grouped by the U.S. Geologic Survey's Major River Basins (MRBs, Crawford and others, 2006). MRB1, covering the New England and Mid-Atlantic River basins, contains NHDPlus Production Units 1 and 2. MRB2, covering the South Atlantic-Gulf and Tennessee

  4. Response characteristics of vegetation and soil environment to permafrost degradation in the upstream regions of the Shule River Basin

    International Nuclear Information System (INIS)

    Chen Shengyun; Liu Wenjie; Qin Xiang; Liu Yushuo; Ren Jiawen; Qin Dahe; Zhang Tongzuo; Hu Fengzu; Chen Kelong

    2012-01-01

    Permafrost degradation exhibits striking and profound influences on the alpine ecosystem, and response characteristics of vegetation and soil environment to such degradation inevitably differ during the entire degraded periods. However, up to now, the related research is lacking in the Qinghai–Tibetan Plateau (QTP). For this reason, twenty ecological plots in the different types of permafrost zones were selected in the upstream regions of the Shule River Basin on the northeastern margin of the QTP. Vegetation characteristics (species diversity, community coverage and biomass etc) and topsoil environment (temperature (ST), water content (SW), mechanical composition (SMC), culturable microorganism (SCM), organic carbon (SOC) and total nitrogen (TN) contents and so on), as well as active layer thickness (ALT) were investigated in late July 2009 and 2010. A spatial–temporal shifts method (the spatial pattern that is represented by different types of permafrost shifting to the temporal series that stands for different stages of permafrost degradation) has been used to discuss response characteristics of vegetation and topsoil environment throughout the entire permafrost degradation. The results showed that (1) ST of 0–40 cm depth and ALT gradually increased from highly stable and stable permafrost (H-SP) to unstable permafrost (UP). SW increased initially and then decreased, and SOC content and the quantities of SCM at a depth of 0–20 cm first decreased and then increased, whereas TN content and SMC showed obscure trends throughout the stages of permafrost degradation with a stability decline from H-SP to extremely unstable permafrost (EUP); (2) further, species diversity, community coverage and biomass first increased and then decreased in the stages from H-SP to EUP; (3) in the alpine meadow ecosystem, SOC and TN contents increased initially and then decreased, soil sandy fractions gradually increased with stages of permafrost degradation from substable (SSP

  5. A mechanism to compensate undesired stiffness in joints of prosthetic hands.

    Science.gov (United States)

    Smit, Gerwin; Plettenburg, Dick; Van der Helm, Frans

    2014-04-01

    Cosmetic gloves that cover a prosthetic hand have a parasitic positive stiffness that counteracts the flexion of a finger joint. Reducing the required input torque to move a finger of a prosthetic hand by compensating the parasitic stiffness of the cosmetic glove. Experimental, test bench. The parasitic positive stiffness and the required input torques of a polyvinyl chloride glove and a silicone glove were measured when flexing a metacarpophalangeal finger joint for 90°. To compensate this positive stiffness, an adjustable compensation mechanism with a negative stiffness was designed and built. A MATLAB model was created to predict the optimal settings of the mechanism, based on the measured stiffness, in order to minimize the required input torque of the total system. The mechanism was tested in its optimal setting with an applied glove. The mechanism reduced the required input torque by 58% for the polyvinyl chloride glove and by 52% for the silicone glove. The total energy dissipation of the joint did not change significantly. This study shows that the undesired positive stiffness in the joint can be compensated with a relatively simple negative stiffness mechanism, which fits inside a finger of a standard cosmetic glove. Clinical relevance This study presents a mechanism that compensates the undesired stiffness of cosmetic gloves on prosthetic hands. As a result, it requires less input force, torque and energy to move the fingers. Application of this mechanism in body-powered hands will reduce the control effort of the user.

  6. Using Cesium-137 technique to study the characteristics of different aspect of soil erosion in the Wind-water Erosion Crisscross Region on Loess Plateau of China

    Energy Technology Data Exchange (ETDEWEB)

    Li Mian E-mail: hnli-mian@163.com; Li Zhanbin; Liu Puling; Yao Wenyi

    2005-01-01

    The most serious soil erosion on Loess Plateau exists in the Wind-water Erosion Crisscross Region. In the past 20 years, the types and intensity of soil erosion and its temporal and spatial distribution were studied, but studies on the difference of soil erosion between slope aspects and slope positions in this area have no report. However, it is very important to analyze and evaluate quantitatively the characteristics of different aspects and positions of soil loss for the prevention and treatment of soil erosion in this area. The spatial pattern of net soil loss on 4 downslope transects in four aspects (east, west, south and north) on a typical Mao (round loess mound) in Liudaogou catchment in Wind-water Erosion Crisscross Region was measured in 2000 using the resident cesium-137 deficit technique. The purposes of this investigation were undertaken to determine whether or not {sup 137}Cs measurement would give a useful indication of the extent of soil loss and their characteristics from cultivated hillsides in different slope aspect and slope position in the study area. The results showed that the difference of soil erosion in different aspect was significant and the erosion rate was in this order: north>east>south>west. Compared with other areas, the difference of erosion rate between north hillside and south hillside was on the contrary, and the possible explanations could be the effect of wind erosion. Also, the percentage of wind erosion was estimated to be at least larger than 18% of total soil loss by comparing the difference of erosion amount in south hillside and north hillside. The erosion rates on different slope positions in all aspects were also different, the highest net soil loss occurred in the lower slope position, and the upper and middle slope positions were slight. The general trend of net soil loss on sloping surface was to increase in fluctuation with increasing downslope distance.

  7. Effects of irrigation regime and salinity on soil characteristics and yield of tomato

    Directory of Open Access Journals (Sweden)

    Rita Leogrande

    2012-03-01

    Full Text Available A field experiment was conducted in Mediterranean conditions to evaluate the effects of different irrigation volumes and water quality on yield performance of tomato crop. The tomato crop was irrigated re-establishing 50 (I1, 75 (I2 and 100% (I3 of the crop evapotranspiration (ETc with two water quality: fresh water with EC 0.9 dS m-1 (FW and saline water with EC 6 dSm-1 (SW. At harvest, total and marketable yield, weight, number, , total soluble solids (TSS and dry matter of fruit were calculated, The results showed no statistical differences among the three different irrigation volumes on tomato yield and quality. The salinity treatment did not affect yield, probably because the soil salinity in the root zone on average remained below the threshold of tomato salt tolerance. Instead, salinity improved fruit quality parameters as dry matter and TSS by 13 and 8 %, respectively. After the first field application of saline water, soil saturated extract cations (SSEC, electrical conductivity of soil paste extract (ECe, sodium absorption ratio (SAR and exchangeable sodium percentage (ESP cations increased; the largest increase of cations, in particular of Na, occurred in the top layer. At the end of the experiment, the absolute value of SSEC, ECe and SAR, for all the effects studied, were lower than those recorded in 2007. This behavior was suitable to the reduced volumes of treatments administered in 2009 in respect to the 2007. Furthermore, the higher total rainfall recorded in 2009 increased the leaching and downward movement of salts out of the sampling depth.

  8. Characteristics of Nitrogen Loss through Surface-Subsurface Flow on Red Soil Slopes of Southeast China

    Science.gov (United States)

    Zheng, Haijin; Liu, Zhao; Zuo, Jichao; Wang, Lingyun; Nie, Xiaofei

    2017-12-01

    Soil nitrogen (N) loss related to surface flow and subsurface flow (including interflow and groundwater flow) from slope lands is a global issue. A lysimetric experiment with three types of land cover (grass cover, GC; litter cover, LC; and bare land, BL) were carried out on a red soil slope land in southeast China. Total Nitrogen (TN) loss through surface flow, interflow and groundwater flow was observed under 28 natural precipitation events from 2015 to 2016. TN concentrations from subsurface flow on BL and LC plots were, on average, 2.7-8.2 and 1.5-4.4 times greater than TN concentrations from surface flow, respectively; the average concentration of TN from subsurface flow on GC was about 36-56% of that recorded from surface flow. Surface flow, interflow and groundwater flow contributed 0-15, 2-9 and 76-96%, respectively, of loss load of TN. Compared with BL, GC and LC intercepted 83-86% of TN loss through surface runoff; GC intercepted 95% of TN loss through subsurface flow while TN loss through subsurface flow on LC is 2.3 times larger than that on BL. In conclusion, subsurface flow especially groundwater flow is the dominant hydrological rout for N loss that is usually underestimated. Grass cover has the high retention of N runoff loss while litter mulch will increase N leaching loss. These findings provide scientific support to control N runoff loss from the red soil slope lands by using suitable vegetation cover and mulching techniques.

  9. The analysis of soil characteristics near the animal feed and fertiliser mill using the Bartington

    Science.gov (United States)

    Azhari, Adinda Syifa; Agustine, Eleonora; Fitriani, Dini

    2017-07-01

    Industrial activities have the potential to make pollution in agricultural land, the waste contains poisonous material and it is dangerous for the environment. In general, waste from factory is dumped directly into the river, but in the current study an object that is going to be conscientious is soil on around mill. There are three sampling sites are around fertilizer plants, feed mills and original uncontaminated soil. This research has been conducted to assess the impact of pollution resulting from the two mills for the environment. Physical parameter that used is magnetic susceptibility. Sampling was conducted using the method of magnetic susceptibility of rock to see the value of low frequency (lf) and shows Frequency Dependent (fd%) using the MS2B Bartington. The results from this study is at a location close to the fertilizer plant at a depth of 0-5 cm has a value susceptibility low frequency ( lf)=187.1 - 494.8, fd (%)=1.37 - 2:46, at a depth of 6-10 cm susceptibility value of low frequency (lf)=211 - 832.7,fd (%)=1.04 - 5.37. Results in the area of animal feed mill at a depth of 0-5 cm value susceptibility low frequency (lf)=111.9 - 325.7, fd (%)=0.8 - 3.57, at a depth of 6-10 cm value susceptibility low frequency (lf)=189.2 to 386.8,fd (%)=0.33 - 3.7. Results in the original soil at a depth of 0-5 cm susceptibility value of low frequency (lf)=1188.7 - 2237.8,fd (%)=2.75 - 4.65, at a depth of 6-10 cm value susceptibility low frequency (lf)=977.7 - 2134.7,fd (%)=3.06 - 6.21. The highest value was in the arealf original, shows the area has a high mineral content andlf lows were in the area near the factory fodder it is caused by high pollution, resulting in lower mineral content in the soil.

  10. Heavy metal contamination characteristic of soil in WEEE (waste electrical and electronic equipment) dismantling community: a case study of Bangkok, Thailand.

    Science.gov (United States)

    Damrongsiri, Seelawut; Vassanadumrongdee, Sujitra; Tanwattana, Puntita

    2016-09-01

    Sue Yai Utit is an old community located in Bangkok, Thailand which dismantles waste electrical and electronic equipment (WEEE). The surface soil samples at the dismantling site were contaminated with copper (Cu), lead (Pb), zinc (Zn), and nickel (Ni) higher than Dutch Standards, especially around the WEEE dumps. Residual fractions of Cu, Pb, Zn, and Ni in coarse soil particles were greater than in finer soil. However, those metals bonded to Fe-Mn oxides were considerably greater in fine soil particles. The distribution of Zn in the mobile fraction and a higher concentration in finer soil particles indicated its readily leachable character. The concentration of Cu, Pb, and Ni in both fine and coarse soil particles was mostly not significantly different. The fractionation of heavy metals at this dismantling site was comparable to the background. The contamination characteristics differed from pollution by other sources, which generally demonstrated the magnification of the non-residual fraction. A distribution pathway was proposed whereby contamination began by the deposition of WEEE scrap directly onto the soil surface as a source of heavy metal. This then accumulated, corroded, and was released via natural processes, becoming redistributed among the soil material. Therefore, the concentrations of both the residual and non-residual fractions of heavy metals in WEEE-contaminated soil increased.

  11. Soil characteristic comparison of fenced and grazed riparian floodplain wetlands in the typical steppe region of the Inner Mongolian Plateau, China.

    Science.gov (United States)

    Wang, Lixin; Liu, Huamin; Liu, Yuhong; Li, Jianwei; Shao, Hongbo; Wang, Wei; Liang, Cunzhu

    2014-01-01

    In recent decades, degradation of ecosystem in the steppe region of the Inner Mongolia Plateau, especially in riparian floodplain wetlands, has become a significant ecological crisis. Not uncommonly, with the increasing of livestock in the Inner Mongolian steppe region, a riparian floodplain wetland is becoming a hotspot area of grazing for local herdsmen. Hence, it is essential to understand degradation mechanisms of riparian floodplain wetland ecosystems caused by extensive grazing. In this study, the spatial distribution of soil compaction, salinity, total nitrogen, total phosphorus, organic carbon, and microbial biomass C and N were investigated. The results showed that grazing led to an increase in soil compaction and soil surface salinity, which significantly lowered levels of total N, P, and TOC in the soil surface. Grazing decreased soil microbial biomass C and N concentration in the lower riparian floodplain wetland, whereas it significantly increased soil microbial biomass C and N concentration in the higher riparian floodplain wetland. Elevation differences in the riparian floodplain wetland increased spatial heterogeneity in the soil and thus resulted in different influence of grazing on wetland soils and ecosystem. Therefore, elevation differences and grazing intensity were the main factors controlling soil characteristics in the riparian floodplain wetland of this region.

  12. Analysis of spatial distribution characteristics of dissolved organic matter in typical greenhouse soil of northern China using three dimensional fluorescence spectra technique and parallel factor analysis model.

    Science.gov (United States)

    Pan, Hong-wei; Lei, Hong-jun; Han, Yu-ping; Xi, Bei-dou; He, Xiao-song; Xu, Qi-gong; Li, Dan

    2014-06-01

    The aim of the present work is to study the soil DOM characteristics in the vegetable greenhouse with a long-term of cultivation. Results showed that the soil DOM mainly consisted of three components, fulvic acid-like (C1), humic acid-like (C2) and protein-like (C3), with C1 as the majority one. The distribution of DOM in space was also studied. In vertical direction, C1 and C2 decreased significantly with the increase in soil depth, while C3 component decreased after increased. The humification coefficient decreased fast from 0-20 to 30-40 cm, and then increased from 30-40 to 40-50 cm. In the horizontal direction, the level of C2 component varied greatly in space, while that of C1 component changed little, and that of C3 component fell in between the above two. The change in the humification degree of each soil layer significantly varied spatially. Humification process of soil organic matter mainly occurred in the surface soil layer. In addition, the humification degree in space also changed significantly. The new ideas of this study are: (1) Analyze the composition and spatial heterogeneity of soil DOM in the vegetable greenhouse; (2) Use three dimensional fluorescence spectra technology and parallel factor analysis model successfully to quantify the components of soil DOM, which provides a new method for the soil DOM analysis.

  13. Irrigating okra with secondary treated municipal wastewater: Observations regarding plant growth and soil characteristics.

    Science.gov (United States)

    Kumar, Vinod; Chopra, A K; Srivastava, Sachin; Singh, Jogendra; Thakur, Roushan Kumar

    2017-05-04

    The present study was carried out to probe the agronomic response of hybrid cultivar of okra (Hibiscus esculentus L. var. JK 7315) grown in secondary treated municipal wastewater irrigated soil with field investigations. The concentrations of the municipal wastewater viz., 10%, 20%, 40%, 60%, 80%, and 100% along with the control (groundwater) were used for the irrigation of the H. esculentus. The study revealed that the concentrations of the municipal wastewater showed significant (p fertigation in comparison to groundwater in both the seasons. The maximum agronomic performance of the H. esculentus was recorded with 60% concentration of the municipal wastewater in both the seasons. The contamination factor of heavy metals varied in the H. esculentus plants and soils. In the H. esculentus plants, following fertigation with municipal wastewater, the contamination factor of manganese was the highest, while that of chromium was the lowest. Intermediate contamination factor were observed for zinc, copper, and cadmium. Therefore, secondary treated municipal wastewater can be used as an agro-fertigant after appropriate dilution (up to 60%) to achieve the maximum yield of the H. esculentus.

  14. Eleven years' effect of conservation practices for temperate sandy loams: II. Soil pore characteristics

    DEFF Research Database (Denmark)

    Abdollahi, Lotfallah; Munkholm, Lars Juhl

    2017-01-01

    for the first two depths (100-cm3 cores), and air permeability for the 18- to 27-cm depth (250-cm3 cores). Moldboard plowing resulted in the best soil quality at two upper depths with higher total porosity, air-filled porosity, air permeability, and gas diffusivity compared with reduced tillage. For instance...... included the tillage treatments: moldboard plowing to 20-cm depth (MP), harrowing to 8- to 10-cm depth (H) and direct drilling (D). Soil cores were taken from the topsoil (4–8, 12–16, 18–27 cm) in mid-autumn 2013 and early spring 2014. Water retention, air permeability, and gas diffusivity was determined......, the volume of pores > 30 μm was more than 0.03 m3 m-3 larger for MP than for D in spring 2014 at the 4- to 8-cm depth. At the 18- to 27-cm depth, direct drilling resulted in a better air permeability and pore continuity index (e.g., air permeability of 18.2 and 11.2 mm2 for D and MP, respectively at −10 k...

  15. The temperature characteristics of biological active period of the peat soils of Bakchar swamp

    Science.gov (United States)

    Kiselev, M. V.; Dyukarev, E. A.; Voropay, N. N.

    2018-01-01

    The results of the study of the peculiarities of the temperature regime in the five basic ecosystems of oligotrophic bogs in the south taiga zone of Western Siberia in 2011-2016 are presented. The soil temperature regime was studied using the atmospheric-soil measuring complex at different depths from surface to 240 cm. All sites were divided into two groups according the bog water level: flooded sites (hollow and open fen) and drained sites (ridge, tall and low ryam). Waterlogged sites are better warmed in the summer period, and slowly freeze in the winter period. The analysis of the annual cycle of temperature showed that the maximum surface temperature is observed in July. The minimum temperature on the surface observed in February or January. The greatest temperature gradient was recorded in the upper 2 cm layer. The gradient at the open fen was -2 °C·cm-1 in February and 1.1 °C·cm-1 in October. The peak of formation of the seasonally frozen layer occurs at the end of autumn, beginning of winter. The degradation of the seasonally frozen layer was observed both from top and bottom, but degradation from the top is faster.

  16. Characteristics of Soil Nutrient and Spatial Distribution on Riparian Zone Restored by Different Vegetation Restoration Methods at Wanzhou Section in the Three Gorges Reservoir Area, China

    Directory of Open Access Journals (Sweden)

    WANG Ya-jing

    2016-03-01

    Full Text Available Riparian vegetation and water-level fluctuation are critical factors influencing soil nutrients and their spatial distribution. Taking Wanzhou section as a case study, the characteristics of soil nutrient and spatial distribution in riparian vegetation restored by different methods in the Three Gorges Reservoir area were uncovered by field investigation and chemical analysis of soil samples collected from the artificial and natural restoration plots, respectively. Results showed that restoration method had significant effect on soil nutrients. The content of soil nutrients in the artificial restoration plot was generally higher than that in the natural recovery plot indicating that artificial restoration promoted accumulation of soil nutrients in vegetation. Under the influence of the reverse seasonal water-level fluctuation, a special spatial distribution pattern that the riparian soil nutrients increased and then decreased with the increasing latitude appeared on the artificial restoration plot. The maximum content of soil nutrients occurred at the middle riparian part(altitude 165 m. However, soil organic matter and total nitrogen increased with the increasing of altitude gradient on the natural restoration plot, and reached the maximum at the upper riparian part(altitude 175 m. The spatial distribution pattern of soil nutrients resulted from the differentiation of water-level fluctuation disturbance and vegetation among altitude gradients. Restoration methods also affected the spatial distribution of soil nutrients as it influenced vegetation restoration. Appropriate tree and shrub species adapting to the disturbance of the reverse seasonal water-level fluctuation should be further introduced to the upper riparian part to promote the vegetation capacity of holding soil nutrients.

  17. Universal solution for the characteristic time and the degree of settlement in nonlinear soil consolidation scenarios. A deduction based on nondimensionalization

    Science.gov (United States)

    Alhama Manteca, Iván; García-Ros, Gonzalo; Alhama López, Francisco

    2018-04-01

    Using the mathematical-physical process of nondimensionalization of governing equations, the problem of nonlinear soil consolidation based on the Cornetti and Battaglio model removing some of the restrictive hypotheses assumed by these authors is studied for the search of the dimensionless groups that govern the characteristic time and the average degree of settlement. The derived groups, once verified by numerical simulations, allow the universal representation of the aforementioned unknowns for the wide range of properties of real soils.

  18. Turbulent characteristics of a semiarid atmospheric surface layer from cup anemometers – effects of soil tillage treatment (Northern Spain

    Directory of Open Access Journals (Sweden)

    S. Yahaya

    Full Text Available This paper deals with the characteristics of turbulent flow over two agricultural plots with various tillage treatments in a fallow, semiarid area (Central Aragon, Spain. The main dynamic characteristics of the Atmospheric Surface Layer (ASL measured over the experimental site (friction velocity, roughness length, etc., and energy budget, have been presented previously (Frangi and Richard, 2000. The current study is based on experimental measurements performed with cup anemometers located in the vicinity of the ground at 5 different levels (from 0.25 to 4 m and sampled at 1 Hz. It reveals that the horizontal wind variance, the Eulerian integral scales, the frequency range of turbulence and the turbulent kinetic energy dissipation rate are affected by the surface roughness. In the vicinity of the ground surface, the horizontal wind variance logarithmically increases with height, directly in relation to the friction velocity and the roughness length scale. It was found that the time integral scale (and subsequently the length integral scale increased with the surface roughness and decreased with the anemometer height. These variations imply some shifts in the meteorological spectral gap and some variations of the spectral peak length scale. The turbulent energy dissipation rate, affected by the soil roughness, shows a z-less stratification behaviour under stable conditions. In addition to the characterization of the studied ASL, this paper intends to show which turbulence characteristics, and under what conditions, are accessible through the cup anemometer.

    Key words. Meteorology and atmospheric dynamics (climatology, turbulence, instruments and techniques

  19. Turbulent characteristics of a semiarid atmospheric surface layer from cup anemometers – effects of soil tillage treatment (Northern Spain

    Directory of Open Access Journals (Sweden)

    S. Yahaya

    2003-10-01

    Full Text Available This paper deals with the characteristics of turbulent flow over two agricultural plots with various tillage treatments in a fallow, semiarid area (Central Aragon, Spain. The main dynamic characteristics of the Atmospheric Surface Layer (ASL measured over the experimental site (friction velocity, roughness length, etc., and energy budget, have been presented previously (Frangi and Richard, 2000. The current study is based on experimental measurements performed with cup anemometers located in the vicinity of the ground at 5 different levels (from 0.25 to 4 m and sampled at 1 Hz. It reveals that the horizontal wind variance, the Eulerian integral scales, the frequency range of turbulence and the turbulent kinetic energy dissipation rate are affected by the surface roughness. In the vicinity of the ground surface, the horizontal wind variance logarithmically increases with height, directly in relation to the friction velocity and the roughness length scale. It was found that the time integral scale (and subsequently the length integral scale increased with the surface roughness and decreased with the anemometer height. These variations imply some shifts in the meteorological spectral gap and some variations of the spectral peak length scale. The turbulent energy dissipation rate, affected by the soil roughness, shows a z-less stratification behaviour under stable conditions. In addition to the characterization of the studied ASL, this paper intends to show which turbulence characteristics, and under what conditions, are accessible through the cup anemometer.Key words. Meteorology and atmospheric dynamics (climatology, turbulence, instruments and techniques

  20. Effects of soil type and rainfall intensity on sheet erosion processes and sediment characteristics along the climatic gradient in central-south China.

    Science.gov (United States)

    Wu, Xinliang; Wei, Yujie; Wang, Junguang; Xia, Jinwen; Cai, Chongfa; Wei, Zhiyuan

    2018-04-15

    Soil erosion poses a major threat to the sustainability of natural ecosystems. The main objective of this study was to investigate the effects of soil type and rainfall intensity on sheet erosion processes (hydrological, erosional processes and sediment characteristics) from temperate to tropical climate. Field plot experiments were conducted under pre-wetted bare fallow condition for five soil types (two Luvisols, an Alisol, an Acrisol and a Ferralsol) with heavy textures (silty clay loam, silty clay and clay) derived separately from loess deposits, quaternary red clays and basalt in central-south China. Rainfall simulations were performed at two rainfall intensities (45 and 90mmh -1 ) and lasted one hour after runoff generation. Runoff coefficient, sediment concentration, sediment yield rate and sediment effective size distribution were determined at 3-min intervals. Runoff temporal variations were similar at the high rainfall intensity, but exhibited a remarkable difference at the low rainfall intensity among soil types except for tropical Ferralsol. Illite was positively correlated with runoff coefficient (perosion varied under the interaction of rainfall characteristics (intensity and duration) and soil types, with amorphous iron oxides and bulk density jointly enhancing soil resistance to erosive forces (Adj-R 2 >88%, perosion processes at the spatial-temporal scale from the perspective of soil properties. Copyright © 2017 Elsevier B.V. All rights reserved.

  1. Phosphorus application to cotton enhances growth, yield, and quality characteristics on a sandy loam soil

    International Nuclear Information System (INIS)

    Ahmad, M.; Ranjha, A.M.

    2009-01-01

    Phosphorus (P) is the second most limiting nutrient in cotton (Gossypium hirsutum L.) production after nitrogen. Under wheat-cotton cropping system of Pakistan most of the farmers apply P fertilizer only to wheat crop. A field experiment was conducted to evaluate the effect of fertilizer P on the growth, yield and fibre quality of cotton on a sandy loam calcareous soil at farmer's field in cotton growing area of district Khanewal, Punjab. Five levels of P (0, 17, 26, 34 and 43 kg P ha /sup -1/) along with 120 kg N and 53 kg K ha/sup -1/ were applied. The response of cotton growth parameters was greater than quality components to P addition in calcareous soil. There was significant increase in the growth and yield parameters with each additional rate of P. The response of number of bolls per plant, boll weight and seed cotton yield was to the tune of 88.23, 16.82 and 42%, respectively at P application rate of 34 kg ha/sup -1/. Cotton quality components (lint %age, fiber length and fiber strength) improved from 2 to 5% where 43 kg P ha/sup -1/ was added. The lint and seed P concentration was little affected by P application as compared to stem and leaves showing its essentiality for cell division and development of meristematic tissue. Phosphorus use, thus not only valuable for wheat crop but also its application to cotton crop is of vital importance in improving both lint yield and quality. (author)

  2. [Effects of supplemental irrigation based on soil moisture on photosynthetic characteristics and enzyme activity of flan leaf in wheat].

    Science.gov (United States)

    He, Jian-ning; Shi, Yu; Zhao, Jun-ye; Zhang, Yong-li; Yu, Zhen-wen

    2015-12-01

    A field experiment was conducted to study the effects of supplemental irrigation based on soil moisture on the photosynthesis characteristics and enzyme activity of flag leaf using the wheat cultivar Jimai 20. Three irrigation treatments were designed with target soil moisture of 65% (W₆₅), 70% (W₇₀) and 75% (W₇₅) both at jointing and anthesis stages. Zero-irrigation ( CK) was used as the control. The results showed that the net photosynthetic rate (Pn) of flag leaf in treatment W₇₀ was dramatically higher than in other treatments from 14 to 21 days after anthesis, as well as sucrose content and sucrose phosphate synthase (SPS) activity. The dry matter mass per area of W₇₀ was higher than that of W₆₅ and CK, and was not significantly different from that of W₇₅. The single stem mass of W₇₀ was higher than that of the other treatments. The activities of superoxide dismutase (SOD) and catalase (CAT) and the soluble protein concentration in flag leaf of W₇₀ were significantly higher than in other treatments from 14 to 28 days after anthesis. The malondialdehyde (MDA) content of W₇₀ was lower than that of W₆₅ and CK, and was not significantly different from that of W₇₅ from 14 to 21 days after anthesis. Grain yields of W₇₀ were 8941.4 and 9125.4 kg · hm⁻² in the 2012-2013 and 2013-2014 wheat growing seasons, showing no significant difference with those of W₇₅, but obviously higher than those of W₆₅ and CK. And the water use efficiency (WUE) of W₇₀ was the highest. Considering grain yield and WUE, maintaining the relative soil water content at 70% by supplemental irrigation both at jointing and anthesis stages was the best treatment.

  3. Cadmium Accumulation Characteristics in Turnip Landraces from China and Assessment of their Phytoremediation Potential for Contaminated Soils

    Directory of Open Access Journals (Sweden)

    Xiong Li

    2016-12-01

    Full Text Available Heavy metal (HM pollution is a global environmental problem that threatens ecosystem and human health. Cadmium (Cd pollution is the most prominent HM pollution type because of its high toxicity, strong migration, and the large polluted area globally. Phytoremediation of contaminated soil is frequently practiced because of its cost-effectiveness and operability and because it has no associated secondary pollution. High-accumulation plants, including those identified as hyperaccumulators, play an important role in phytoremediation. Therefore, screening of plants to identify hyperaccumulators is important for continued phytoremediation. In the present study, we investigated the Cd tolerance and accumulation capabilities of 18 turnip landraces from China under a soil experiment with known Cd level. The results indicated that turnip has a high capacity for Cd accumulation. Furthermore, significant differences in Cd tolerance and accumulation characteristics were found among different landraces when they grew at 50 mg kg−1 (dry weight Cd concentration. Among the studied landraces, five turnip landraces met the requirements of Cd hyperaccumulators and three landraces were identified as potential candidates. However, the total Cd content accumulated by individual plant of different turnip landraces was dependent on both the Cd accumulation capacity and plant biomass. Compared with some reported Cd hyperaccumulators, turnip not only shows a high Cd-accumulation capacity but also has rapid growth and a wide distribution area. These advantages indicate that turnip may have considerable potential for phytoremediation of Cd-contaminated soil. Furthermore, the study also indicates that it is not advisable to consume turnip cultivated in an environment that exceeds safe Cd levels.

  4. Operation condition for continuous anti-solvent crystallization of CBZ-SAC cocrystal considering deposition risk of undesired crystals

    Science.gov (United States)

    Nishimaru, Momoko; Nakasa, Miku; Kudo, Shoji; Takiyama, Hiroshi

    2017-07-01

    Crystallization operation of cocrystal production has deposition risk of undesired crystals. Simultaneously, continuous manufacturing processes are focused on. In this study, conditions for continuous cocrystallization considering risk reduction of undesired crystals deposition were investigated on the view point of thermodynamics and kinetics. The anti-solvent cocrystallization was carried out in four-component system of carbamazepine, saccharin, methanol and water. From the preliminary batch experiment, the relationships among undesired crystal deposition, solution composition decided by mixing ratio of solutions, and residence time for the crystals were considered, and then the conditions of continuous experiment were decided. Under these conditions, the continuous experiment was carried out. The XRD patterns of obtained crystals in the continuous experiment showed that desired cocrystals were obtained without undesired crystals. This experimental result was evaluated by using multi-component phase diagrams from the view point of the operation point's movement. From the evaluation, it was found that there is a certain operation condition which the operation point is fixed with time in the specific domain without the deposition risk of undesired single component crystals. It means the possibility of continuous production of cocrystals without deposition risk of undesired crystals was confirmed by using multi-component phase diagrams.

  5. Research on China's aquaculture efficiency evaluation and influencing factors with undesirable outputs

    Science.gov (United States)

    Ji, Jianyue; Wang, Pingping

    2015-06-01

    Taking the aquaculture area, the number of farming boats and that of aquaculturist as input variables, the aquaculture production as desirable output variable and polluted economic loss as undesirable output variable, this paper conducts SBM model to evaluate the aquaculture efficiency based on the data of 16 aquaculture-developed provinces in China from 2004 to 2011. The results show the efficiency in China has not changed much in recent years with the efficiency values mainly between 0.39 and 0.53, and the efficiency of marine-aquaculture-dominated provinces is generally higher than that of freshwater-aquaculture-dominated ones. To analyze the difference under the efficiency, the panel Tobit model is used with education level factor, training factor, technology extension factor, technical level factor, scale factor and species factor as the efficiency influencing factors. The results show that technology extension factor and technical level factor have significant positive influence.

  6. The application of game theory and cognitive economy to analyze the problem of undesired location

    International Nuclear Information System (INIS)

    Villani, S.

    2008-01-01

    The analysts of the processes of public bodies decision - taking have long been discussing on the establishment of proper strategies to manage environmental conflicts - above all the so-called problems of undesired location of public works and facilities - efficiently (i.e. on a short-period basis so as to grant decision and agreement stability) and fairly (the parties' satisfaction is itself a further guarantee of decision and agreement stability). Each strategy, anyway, is still in progress, like a universe to create and explore. Therefore, in this paper, we will focus on the analysis of the problem and provide as well some theoretical proposals to arrange a new interpreting model of public bodies decision-taking processes based on the achievements of two new subject-matters: evolutionary game theory and cognitive economy. Both sciences share their investigation field with law and economic science. [it

  7. Undesirable sulphur and carbonyl flavor compounds in UHT milk: a review.

    Science.gov (United States)

    Zabbia, Alex; Buys, Elna M; De Kock, Henriette L

    2012-01-01

    Ultra High Temperature (UHT) processing leads to the formation of "cooked" and "flat" flavors in milk. These undesirable notes occur due to the volatile formation of a variety of sulphur containing compounds, methyl ketones and aliphatic aldehydes, derived from the constituents of the milk's matrix during thermal processing and storage. The "cooked" flavor of UHT milk is associated with the presence of a variety of sulphur containing compounds while the "stale" flavor is characterized by the dissipation of these sulphur volatiles and an increase of the formation and presence of both methyl ketones and aliphatic aldehydes over time. The extent to which the individual volatiles contribute to the overall flavor of UHT milk is not clear. The proposed formation of these volatiles, that is, the methods to control the intensity of "cooked" and "stale" flavors associated with UHT milk and extraction techniques for the isolation of these volatiles from milk, have been reviewed.

  8. Linking air and water transport in intact soils to macropore characteristics inferred from X-ray computed tomography

    DEFF Research Database (Denmark)

    Katuwal, Sheela; Nørgaard, Trine; Møldrup, Per

    2015-01-01

    and direct macropore visualization by X-ray CT scanning were carried out on 17 large (19-cm diam.; 20-cm length) undisturbed soil columns sampled across a field site (Silstrup, Denmark) with natural gradients in texture and density. Air permeability (ka) at in-situ water content and -20 hPa of matric...... potential, and 5% arrival time of tracer (time taken to recover 5% of the applied tracer in the outflow) were measured and linked to macropore characteristics (macro-porosity, macro-porosity of the restricting layer, number of macropores, branches, node density, and length density) quantified via X-ray CT...... positively correlated with macro-porosity (R2 = 0.77 for ka at -20 hPa; R2 = 0.59 for 5% arrival time) and macro-porosity of the restricting layer (R2 = 0.80 for ka at -20 hPa; R2 = 0.70 for 5% arrival time). High negative correlations with soil bulk density were found for ka, 5% arrival time, and macro...

  9. Removing undesirable color and boosting biological activity in red beet extracts using gamma irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Seung Sik; Lee, Eun Mi; Hong, Sung Hyun; Bai, Hyoung Woo; Chung, Byung Yeoup [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Lee, In Chul [Youngdong University, Youngdong (Korea, Republic of)

    2011-10-15

    Red beet (Beta vulgaris L.) is a traditional and popular vegetable distributed in many part of the world and has been used as a natural colorant in many dairy products, beverages, candies and cattle products. Red beet roots contain two groups of betalain pigments, redviolet betacyanins and yellow betaxanthins. Betalains possess several biological activities such as antioxidant, anti-inflammatory, hepatoprotective, and anticancer properities. Recent trend of using natural products in industries tends toward multifunctional, high quality, and highpriced value foods and cosmetics. To meet the needs of consumers, cosmetics, medicine, and foods should contain the proper amount of natural products. Although the color removal processes such as filtration and absorption by clay are still useful, these procedures are difficult, time-consuming and costly. To overcome this problem, the radiation technology has emerged as a new way. Radiation technology has been applied to the decomposition and decoloration of pigment and is an efficient technique for inactivating pathogens, removing undesirable color in biomaterial extracts and improving or maintaining biological activities. Gamma-irradiation and electron beamirradiation techniques in previous reports were applied in order to remove any undesirable color and to improve or maintain biological activities of various extracts such as green tea leaves, licorice root, and S. chinensis fruits. Latorre et al. reported that betacyanin concentration decreased with the irradiation dose and significantly, in 35%, after 2.0 kGy of gamma-ray, whereas betaxathin concentration increased (about 11%-ratio with respect to control) after 1 kGy but decreased (about 19%) after 2 kGy. However, they did not try to analysis for completed removal of red beet pigments. Therefore, it is necessary to find the optimum irradiation dose for entirely removing red pigments in red beet. The aim of this work was to address the effects of the color removal and

  10. Removing undesirable color and boosting biological activity in red beet extracts using gamma irradiation

    International Nuclear Information System (INIS)

    Lee, Seung Sik; Lee, Eun Mi; Hong, Sung Hyun; Bai, Hyoung Woo; Chung, Byung Yeoup; Lee, In Chul

    2011-01-01

    Red beet (Beta vulgaris L.) is a traditional and popular vegetable distributed in many part of the world and has been used as a natural colorant in many dairy products, beverages, candies and cattle products. Red beet roots contain two groups of betalain pigments, redviolet betacyanins and yellow betaxanthins. Betalains possess several biological activities such as antioxidant, anti-inflammatory, hepatoprotective, and anticancer properities. Recent trend of using natural products in industries tends toward multifunctional, high quality, and highpriced value foods and cosmetics. To meet the needs of consumers, cosmetics, medicine, and foods should contain the proper amount of natural products. Although the color removal processes such as filtration and absorption by clay are still useful, these procedures are difficult, time-consuming and costly. To overcome this problem, the radiation technology has emerged as a new way. Radiation technology has been applied to the decomposition and decoloration of pigment and is an efficient technique for inactivating pathogens, removing undesirable color in biomaterial extracts and improving or maintaining biological activities. Gamma-irradiation and electron beamirradiation techniques in previous reports were applied in order to remove any undesirable color and to improve or maintain biological activities of various extracts such as green tea leaves, licorice root, and S. chinensis fruits. Latorre et al. reported that betacyanin concentration decreased with the irradiation dose and significantly, in 35%, after 2.0 kGy of gamma-ray, whereas betaxathin concentration increased (about 11%-ratio with respect to control) after 1 kGy but decreased (about 19%) after 2 kGy. However, they did not try to analysis for completed removal of red beet pigments. Therefore, it is necessary to find the optimum irradiation dose for entirely removing red pigments in red beet. The aim of this work was to address the effects of the color removal and

  11. Linkage of within vineyard soil properties, grapevine physiology, grape composition and sensory characteristics in a premium wine grape vineyard.

    Science.gov (United States)

    Smart, David; Hess, Sallie; Ebeler, Susan; Heymann, Hildegarde; Plant, Richard

    2014-05-01

    Analysis of numerous vineyards has revealed a very high degree of variation exists at the within vineyard scale and may outweigh in some cases broader mesoclimatic and geological factors. For this reason, selective harvest of high quality wine grapes is often conducted and based on subjective field sensory analysis (taste). This is an established practice in many wine growing regions. But the relationships between these subjective judgments to principle soil and grapevine physiological characteristics are not well understood. To move toward greater understanding of the physiological factors related to field sensory evaluation, physiological data was collected over the 2007 and 2008 growing seasons in a selectively harvested premium production Napa Valley estate vineyard, with a history of selective harvesting based on field sensory evaluation. Data vines were established and remained as individual study units throughout the data gathering and analysis phase, and geographic information systems science (GIS) was used to geographically scale physiological and other data at the vineyard level. Areas yielding grapes with perceived higher quality (subjective analysis) were characterized by vines with 1) statistically significantly lower (P water potential (LWP) both pre-dawn (PD) and midday (MD), 2) smaller berry diameter and weight, 3) lower pruning weights, and 4) higher soluble solids (Brix). Strong positive correlations emerged between June ψPD and pre-harvest grape berry diameter (R2 = 0.616 in 2007 and 0.413 in 2008) and similar strong correlations existed for berry weight (R2 = 0.626 in 2007 and 0.554 in 2008). A trained sensory panel performed a sensory analysis and characterized fruit using and a multivariate, principal components, analysis (PCA). This approach indicated that grapes from vines with lowest midday leaf water potential at veraison ( -1.5 MPa were characterized by vegetal flavors and astringent and bitter seeds and skins. Data from vines were

  12. [Characteristics of Soil Respiration along Eroded Sloping Land with Different SOC Background on the Hilly Loess Plateau].

    Science.gov (United States)

    Chen, Gai; Xu, Ming-xiang; Zhang, Ya-feng; Wang, Chao-hua; Fan, Hui-min; Wang, Shan-shan

    2015-09-01

    This study aimed to characterize soil respiration along eroded sloping land at erosion and deposition area under different soil organic carbon(SOC) levels, and linked the relationship between soil respiration and soil temperature, soil moisture, SOC and slope position. Experiments were carried out in the plots of S type slopes include five different soil organic carbon levels in the Loess Hilly Region. The S type slopes were divided into control area at the top of the slope, erosion area at the middle of the slope and deposition area at the toe of the slope. We found that soil temperature had a greater impact on soil respiration in the deposition area, whereas soil moisture had a greater impact on soil respiration in the erosion area compared among control area, erosion area and deposition area. In addition, SOC was the most important factor affecting soil respiration, which can explain soil respiration variation 54. 72%, followed by soil moisture, slope position and soil temperature, which explain soil respiration variation 18. 86% , 16. 13% and 10. 29%, respectively. Soil respiration response to erosion showed obvious on-site and off-site effects along the eroded sloping land. Soil respiration in the erosion area was reduced by 21. 14% compared with control area, and soil respiration in the deposition area was increased by 21. 93% compared with control area. Erosion effect on source and sink of carbon emission was correlated with SOC content of the eroded sloping land. When SOC content was higher than 6. 82 g.kg-1, the slope. erosion tended to be a carbon sequestration process, and when SOC content was lower than 3.03 g.kg-1, the slope erosion tended to be a process of the carbon emission source. The model could reflect the relationship between soil respiration and independent variables of soil organic carbon content, soil temperature and moisture.

  13. The Effect of Drying-Wetting Cycle’s Repetition to the Characteristic of Natural and Stabilization Residual Soils Jawa Timur - Indonesia

    Science.gov (United States)

    Muntaha, M.

    2017-11-01

    Indonesia, which located in tropical region, continuously undergoes wetting and drying cycles due to the changeable seasons. An important role in activating the clay minerals on tropical residual soils is the main factor that affects the static and dynamic properties, such as: volume change, soil suction and dynamic modulus. The purpose of this paper is to evaluate the effect of drying-wetting cycles repetition on volume change, soil suction and mechanical characteristics of natural and stabilization of residual soils from Jawa Timur - Indonesia. The natural undisturbed and stabilized residual soil sample was naturally and gradually dried up with air to 25%, 50%, 75%, and 100 % of the initial water content. The wetting processes were carried out with the gradual increment water content of 25 %(wsat - wi), 50 %(wsat - wi), 75 %(wsat - wi), up to 100 %(wsat - wi). The Direct Shear test is used to measure the mechanic properties, and Whatman filter paper No. 42 is used to measure the soil suction. The drying-wetting processes were carried out for 1, 2, 4, and 6 cycles. The laboratory test results showed that, the void ratio decreased, the unit weight, cohesion and the internal friction angle were increasing due to stabilization. Drying-wetting cycle repetition reduces void ratio, negative pore-water pressure, cohesion and internal friction angle of natural and stabilized soils. Briefly, the decreased of mechanical soil properties was proven from the physical properties change observation.

  14. CHARACTERISTICS OF COMPOSTED BIO-TOILET RESIDUE AND ITS POTENTIAL USE AS A SOIL CONDITIONER

    Directory of Open Access Journals (Sweden)

    Jovita Triastuti

    2016-10-01

    Full Text Available Bio-toilet is a dry toilet where human excreta is trapped in a lignocelluloses soil matrix such as wood sawdust, then it is decomposed by aerobic  bacteria to organic compost rich in minerals such as N, P, and K. The study aimed to characterize the bio-toilet residue and its potential use as a soil conditioner for Jatropha curcas. The study was conducted in a private school of Daarut Tauhid in Bandung West Java. A bio-toilet S-50 type of Japan was constructed consisting of a composting chamber, mixer, heater, exhaust fan, and closet. The composting chamber was filled with 63 kg of Albizzia sawdust. Feces and urine was loaded daily by 54 students for 122-day observation. At the end of observation, the decomposed bio-toilet residue was evaluated for its physical properties such as bulk density (rb, porosity (%, and water retention (WR. Chemical properties such as pH, C/N ratio, N, P, and K, as well as microbiological properties such as numbers of bacteria, fungi, and worm eggs were evaluated at 14 and 122 days of decomposition process. Effect of the composted bio-toilet residue as plant growth media was evaluated using J. curcass as a plant indicator. Before it was used as a growth media, the composted bio-toilet residue was dried in a room temperature for 30 days. The experiment was designed in a completely randomized design 2 x 4 factorial with three replications. The first factor was the rate of composted biotoilet residue, i.e., 0, 20, 40, and 60% based on weight of the growth media mixture (1500 g pot-1, and the second was NPK fertilizer addition at 0 and 2 g pot-1. Each pot was planted with 2-month old of J. curcas seedlings. Parameters evaluated were leaf number, leaf area, stem height, and stem diameter measured at 12 weeks after planting. The results showed that the biotoilet residue was suitable as soil conditioner because it had high porosity (76%, low bulk density (0.19 g cm-3, high water retention (2.6 ml g-1 DM, neutral pH (6.9, C

  15. Physical and chemical characteristics of plutonium in existing contaminated soils and sediments

    International Nuclear Information System (INIS)

    Tamura, T.

    1975-01-01

    Plutonium from three sites was studied to provide information necessary in understanding its behavior and fate under prevailing conditions. Plutonium in soils from the Nevada Test Site (NTS) was predominantly associated (50 to 75 percent) with the coarse silt (53 to 20 μm) fraction. The plutonium in samples from Oak Ridge National Laboratory (ORNL) and Mound Laboratory (ML) was predominantly in the clay size (less than 2 μm). The solubility in citric acid was about 20 to 25 percent in the ORNL sample and 40 to 50 percent in the ML sample. Density gradient segregation of the clay size fraction of the ML sample showed the activity distribution to be directly related to the weight of the recovered fraction with enhanced contribution by the very light organic fraction. Approximately 71 percent was found in the 2.3 to 2.4 g/cm 3 fraction which contained 65 weight percent of the clay and 16 percent in the less than 1.8 g/cm 3 fraction (organic fraction) which contained 6 percent of the weight fraction

  16. Reliable and accurate point-based prediction of cumulative infiltration using soil readily available characteristics: A comparison between GMDH, ANN, and MLR

    Science.gov (United States)

    Rahmati, Mehdi

    2017-08-01

    Developing accurate and reliable pedo-transfer functions (PTFs) to predict soil non-readily available characteristics is one of the most concerned topic in soil science and selecting more appropriate predictors is a crucial factor in PTFs' development. Group method of data handling (GMDH), which finds an approximate relationship between a set of input and output variables, not only provide an explicit procedure to select the most essential PTF input variables, but also results in more accurate and reliable estimates than other mostly applied methodologies. Therefore, the current research was aimed to apply GMDH in comparison with multivariate linear regression (MLR) and artificial neural network (ANN) to develop several PTFs to predict soil cumulative infiltration point-basely at specific time intervals (0.5-45 min) using soil readily available characteristics (RACs). In this regard, soil infiltration curves as well as several soil RACs including soil primary particles (clay (CC), silt (Si), and sand (Sa)), saturated hydraulic conductivity (Ks), bulk (Db) and particle (Dp) densities, organic carbon (OC), wet-aggregate stability (WAS), electrical conductivity (EC), and soil antecedent (θi) and field saturated (θfs) water contents were measured at 134 different points in Lighvan watershed, northwest of Iran. Then, applying GMDH, MLR, and ANN methodologies, several PTFs have been developed to predict cumulative infiltrations using two sets of selected soil RACs including and excluding Ks. According to the test data, results showed that developed PTFs by GMDH and MLR procedures using all soil RACs including Ks resulted in more accurate (with E values of 0.673-0.963) and reliable (with CV values lower than 11 percent) predictions of cumulative infiltrations at different specific time steps. In contrast, ANN procedure had lower accuracy (with E values of 0.356-0.890) and reliability (with CV values up to 50 percent) compared to GMDH and MLR. The results also revealed

  17. Out of sight - Profiling soil characteristics, nutrients and microbial communities affected by organic amendments down to one meter in a long-term maize cultivation experiment

    Science.gov (United States)

    Lehtinen, Taru; Mikkonen, Anu; Zavattaro, Laura; Grignani, Carlo; Baumgarten, Andreas; Spiegel, Heide

    2016-04-01

    Soil characteristics, nutrients and microbial activity in the deeper soil layers are topics not of-ten covered in agricultural studies since the main interest lies within the most active topsoils and deep soils are more time-consuming to sample. Studies have shown that deep soil does matter, although biogeochemical cycles are not fully understood yet. The main aim of this study is to investigate the soil organic matter dynamics, nutrients and microbial community composition in the first meter of the soil profiles in the long-term maize cropping system ex-periment Tetto Frati, in the vicinity of the Po River in Northern Italy. The trial site lies on a deep, calcareous, free-draining soil with a loamy texture. The following treatments have been applied since 1992: 1) maize for silage with 250 kg mineral N ha-1 (crop residue removal, CRR), 2) maize for grain with 250 kg mineral N ha-1 (crop residue incorporation, CRI), 3) maize for silage with 250 kg bovine slurry N ha-1 (SLU), 4) maize for silage with 250 kg farm yard manure N ha-1 (FYM). Soil characteristics (pH, carbonate content, soil organic carbon (SOC), aggregate stability (WSA)), and nutrients (total nitrogen (Nt), CAL-extractable phos-phorous (P) and potassium (K), potential N mineralisation) were investigated. Bacteri-al community composition was investigated with Ion PGM high-throughput sequencing at the depth of 8000 sequences per sample. Soil pH was moderately alkaline in all soil samples, in-creasing with increasing soil depth, as the carbonate content increased. SOC was significantly higher in the treatments with organic amendments (CRI, SLU and FYM) compared to CRR in 0-25 cm (11.1, 11.6, 14.7 vs. 9.8 g kg-1, respectively), but not in the deeper soil. At 50-75 cm soil depth FYM treatment revealed higher WSA compared to CRR, as well as higher CAL-extractable K (25 and 15 mg kg-1, respectively) and potential N mineralisation (11.30 and 8.78 mg N kg-1 7d-1, respectively). At 75-100 cm soil depth, SLU and

  18. Sap flow characteristics of neotropical mangroves in flooded and drained soils

    Science.gov (United States)

    Krauss, Ken W.; Young, P. Joy; Chambers, Jim L.; Doyle, Thomas W.; Twilley, Robert R.

    2007-01-01

    Effects of flooding on water transport in mangroves have previously been investigated in a few studies, most of which were conducted on seedlings in controlled settings. In this study, we used heat-dissipation sap probes to determine if sap flow (Js) attenuates with radial depth into the xylem of mature trees of three south Florida mangrove species growing in Rookery Bay. This was accomplished by inserting sap probes at multiple depths and monitoring diurnal flow. For most species and diameter size class combinations tested, Js decreased dramatically beyond a radial depth of 2 or 4 cm, with little sap flow beyond a depth of 6 cm. Mean Js was reduced on average by 20% in Avicennia germinans (L.) Stearn, Laguncularia racemosa (L.) Gaertn. f. and Rhizophora mangle L. trees when soils were flooded. Species differences were highly significant, with L. racemosahaving the greatest midday Js of about 26g H2O H2O m−2s−1 at a radial depth of 2 cm compared with a mean for the other two species of about 15 g H2O m−2s−1. Sap flow at a depth of 2 cm in mangroves was commensurate with rates reported for other forested wetland tree species. We conclude that: (1) early spring flooding of basin mangrove forests causes reductions in sap flow in mature mangrove trees; (2) the sharp attenuations in Js along the radial profile have implications for understanding whole-tree water use strategies by mangrove forests; and (3) regardless of flood state, individual mangrove tree water use follows leaf-level mechanisms in being conservative.

  19. Topological characteristics underpin intermittency and anomalous transport behavior in soil-like porous media

    Science.gov (United States)

    Holzner, M.; Morales, V.; Willmann, M.; Jerjen, I.; Kaufmann, R.; Dentz, M.

    2016-12-01

    Continuum models of porous media are based on the validity of the Darcy equation for fluid and Fick's law for scalar fluxes on a representative elementary volume. Fluctuations of pore-scale flow and scalar transport are averaged out and represented in terms of effective parameters such as hydrodynamic dispersion. However, the intermittent behavior of pore-scale flow impacts on the nature of particle and scalar transport, and it determines the way dissolved substances mix and react. The understanding of the origin of these processes is of both fundamental and practical importance in applications ranging from reactive transport in groundwater flow to diffusion in fuel cells or biological systems. A central issue in porous medium flow is therefore to relate intermittent behavior of Lagrangian velocity at pore scale imposed by the complex pore network geometry to transport properties at larger scales. Lagrangian measurements in porous systems are nonetheless scarce and most experimental techniques do not provide access to all three velocity components. In this contribution we report 3D measurements of Lagrangian velocity in soil-like porous media. We complement these measurements with detailed X-ray scans of the pore network. We find sharp velocity transitions close to pore throats, and low flow variability in the pore bodies, which gives rise to stretched exponential Lagrangian velocity and acceleration distributions characterized by a sharp peak at low velocity and a superlinear evolution of particle dispersion. We demonstrate that porosity and pore size distribution alone cannot explain the observed features of the flow. Rather, anomalous transport is better interpreted in terms of how pores of various geometries are interconnected. We reproduce the main observations using a continuous-time random walk (CTRW) model revealing the main features that control the system and showing the potential of this simple model to capture transport in complex geometries.

  20. Soil water retention, air flow and pore structure characteristics after corn cob biochar application to a tropical sandy loam

    DEFF Research Database (Denmark)

    Amoakwah, Emmanuel; Frimpong, Kwame Agyei; Okae-Anti, D

    2017-01-01

    Soil structure is a key soil physical property that affects soil water balance, gas transport, plant growth and development, and ultimately plant yield. Biochar has received global recognition as a soil amendment with the potential to ameliorate the structure of degraded soils. We investigated how...... corn cob biochar contributed to changes in soil water retention, air flow by convection and diffusion, and derived soil structure indices in a tropical sandy loam. Intact soil cores were taken from a field experiment that had plots without biochar (CT), and plots each with 10 t ha− 1 (BC-10), 20 t ha...... to significant increase in soil water retention compared to the CT and BC-10 as a result of increased microporosity (pores biochar had minimal impact. No significant influence of biochar was observed for ka and Dp/D0 for the BC treatments compared to the CT despite...

  1. 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.

  2. Characteristics of subsidence of power plants built on compressible foundation soils

    International Nuclear Information System (INIS)

    Peter, P.

    1987-01-01

    The characteristics are presented of the subsoil of the foundation slab for the reactors of the Bohunice V-2 nuclear power plant. The problems are discussed of the inclination of the foundation slab of the reactor units with regard to its uneven subsidence. The results are presented of the measurement and calculation of the process of subsidence, and extrapolation calculations are made. The inclination of the foundation slabs of units 1 and 2 was compensated in 1984 by adjusting the pressure vessels into counter-inclination. The pressure vessel of unit 1 did not incline any further, in unit 2 the process slowed down briefly but then continued at a quicker pace. The causes are discussed and an analysis made of the subsidence of the foundation slabs of the two units. The prognosis shows that during the service life of the nuclear power plant the inclining process should not exceed the tolerance limit. (J.B.). 1 tab., 11 figs., 19 refs

  3. Undesired small RNAs originate from an artificial microRNA precursor in transgenic petunia (Petunia hybrida.

    Directory of Open Access Journals (Sweden)

    Yulong Guo

    Full Text Available Although artificial microRNA (amiRNA technology has been used frequently in gene silencing in plants, little research has been devoted to investigating the accuracy of amiRNA precursor processing. In this work, amiRNAchs1 (amiRchs1, based on the Arabidopsis miR319a precursor, was expressed in order to suppress the expression of CHS genes in petunia. The transgenic plants showed the CHS gene-silencing phenotype. A modified 5' RACE technique was used to map small-RNA-directed cleavage sites and to detect processing intermediates of the amiRchs1 precursor. The results showed that the target CHS mRNAs were cut at the expected sites and that the amiRchs1 precursor was processed from loop to base. The accumulation of small RNAs in amiRchs1 transgenic petunia petals was analyzed using the deep-sequencing technique. The results showed that, alongside the accumulation of the desired artificial microRNAs, additional small RNAs that originated from other regions of the amiRNA precursor were also accumulated at high frequency. Some of these had previously been found to be accumulated at low frequency in the products of ath-miR319a precursor processing and some of them were accompanied by 3'-tailing variant. Potential targets of the undesired small RNAs were discovered in petunia and other Solanaceae plants. The findings draw attention to the potential occurrence of undesired target silencing induced by such additional small RNAs when amiRNA technology is used. No appreciable production of secondary small RNAs occurred, despite the fact that amiRchs1 was designed to have perfect complementarity to its CHS-J target. This confirmed that perfect pairing between an amiRNA and its targets is not the trigger for secondary small RNA production. In conjunction with the observation that amiRNAs with perfect complementarity to their target genes show high efficiency and specificity in gene silencing, this finding has an important bearing on future applications of ami

  4. Impacts of biochar addition on soil dissolved organic matter characteristics in a wheat-maize rotation system in Loess Plateau of China.

    Science.gov (United States)

    Zhang, Afeng; Zhou, Xu; Li, Ming; Wu, Haiming

    2017-11-01

    Biochar amendment in soil has the potential to sequester carbon, improve soil quality and mitigate greenhouse gas (GHG) emission in agriculture, but the impact of biochar amendments on dissolved organic matter (DOM) properties of soils in the fertilized agro-ecosystem has received little research attention. This study performed a long-term field experiment to assess the influence of biochar amendments (different addition rate: 4 t ha -1 and 8 t ha -1 ) on DOM characteristics in soils in wheat-maize rotation system in Loess Plateau of China by exploiting fluorescence excitation-emission spectrophotometry and parallel factor analysis (EEM-PARAFAC). Our results showed that the content of soil DOM was significantly influenced by the addition of biochar, and the higher biochar addition markedly increased the mean concentration of dissolved organic carbon (DOC) (from 83.99 mg kg -1 to 144.27 mg kg -1 ) in soils under the same fertilizer application. Three identified fluorescent components (fulvic acid-like, humic acid-like and tryptophan-like) were found, and fluorescence intensity of those components (especially humic-like material) was enhanced with the increasing DOC in the biochar treatments but the composition of DOM was not changed. These findings would be beneficial to understand the biochar's effects and processes in decreasing GHG emissions from soils. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. [Change characteristics of soil moisture and nutrients in rain-fed winter wheat field under different fertilization modes in Southern Shanxi of China during summer fallow period].

    Science.gov (United States)

    Li, Ting-Liang; Xie, Ying-He; Hong, Jian-Ping; Feng, Qian; Sun, Cheng-Hong; Wang, Zhi-Wei

    2013-06-01

    In 2009-2011, a field experiment was conducted in a rain-fed winter wheat field in Southern Shanxi of China to study the effects of different fertilization modes on the change characteristics of soil moisture and nitrate-N contents in 0-200 cm layer and of soil available phosphorus (Oslen-P) and potassium contents in 0-40 cm layer during summer fallow period (from June to September). Three fertilization modes were installed, i. e., conventional fertilization (CF), recommended fertilization (RF), and ridge film furrow planting (RFFP) combined with straw mulch. The results showed that the rainfall in summer fallow period could complement the consumed water in 0-200 cm soil layer in dryland wheat field throughout the growth season, and more than 94% of the water storage was in 0-140 cm soil layer, with the fallow efficiency ranged from 6% to 27%. The rainfall in summer fallow period caused the soil nitrate-N moving downward. 357-400 mm rainfall could make the soil nitrate-N leaching down to 100 cm soil layer, with the peak in 20-40 cm soil layer. Straw mulching or plastic film with straw mulch in summer fallow period could effectively increase the Oslen-P and available K contents in 0-40 cm soil layer, and the accumulative increment in three summer fallow periods was 16-45% and 36-49%, respectively. Among the three modes, the binary coverage mode of RFFP plus furrow straw mulching had the best effect in maintaining soil water and fertility. The accumulative water storage and mineral N in 0-200 cm soil layer in three summer fallow periods were up to 215 mm and 90 kg x hm(-2), and the accumulative Oslen-P and available K contents in plough layer were increased by 2.7 mg x kg(-1) and 83 mg x kg(-1), re