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Sample records for range soils principal

  1. Preliminary study of soil permeability properties using principal component analysis

    Science.gov (United States)

    Yulianti, M.; Sudriani, Y.; Rustini, H. A.

    2018-02-01

    Soil permeability measurement is undoubtedly important in carrying out soil-water research such as rainfall-runoff modelling, irrigation water distribution systems, etc. It is also known that acquiring reliable soil permeability data is rather laborious, time-consuming, and costly. Therefore, it is desirable to develop the prediction model. Several studies of empirical equations for predicting permeability have been undertaken by many researchers. These studies derived the models from areas which soil characteristics are different from Indonesian soil, which suggest a possibility that these permeability models are site-specific. The purpose of this study is to identify which soil parameters correspond strongly to soil permeability and propose a preliminary model for permeability prediction. Principal component analysis (PCA) was applied to 16 parameters analysed from 37 sites consist of 91 samples obtained from Batanghari Watershed. Findings indicated five variables that have strong correlation with soil permeability, and we recommend a preliminary permeability model, which is potential for further development.

  2. The Use of Principal Components in Long-Range Forecasting

    Science.gov (United States)

    Chern, Jonq-Gong

    Large-scale modes of the global sea surface temperatures and the Northern Hemisphere tropospheric circulation are described by principal component analysis. The first and the second SST components well describe the El Nino episodes, and the El Nino index (ENI), suggested in this study, is consistent with the winter Southern Oscillation index (SOI), where this ENI is a composite component of the weighted first and second SST components. The large-scale interactive modes of the coupling ocean-atmosphere system are identified by cross-correlation analysis The result shows that the first SST component is strongly correlated with the first component of geopotential height in lead time of 6 months. In the El Nino-Southern Oscillation (ENSO) evolution, the El Nino mode strongly influences the winter tropospheric circulation in the mid -latitudes for up to three leading seasons. The regional long-range variation of climate is investigated with these major components of the SST and the tropospheric circulation. In the mid-latitude, the climate of the central United States shows a weak linkage with these large-scale circulations, and the climate of the western United States appears to be consistently associated with the ENSO modes. These El Nino modes also show a dominant influence on Eastern Asia as evidenced in Taiwan Mei-Yu patterns. Possible regional long-range forecasting schemes, utilizing the complementary characteristics of the winter El Nino mode and SST anomalies, are examined with the Taiwan Mei-Yu.

  3. Lead Pollution of Shooting Range Soils

    African Journals Online (AJOL)

    NICOLAAS

    range. Most of the shooting range soils contained high levels of Pb in the range above 2000 mg kg–1 far exceeding the United States ... N. Sehube, R. Kelebemang, O. Totolo, M. Laetsang, O. Kamwi and P. Dinake,. 21 ..... Eng. Sci., 1999, 16,.

  4. Characterization of soil chemical properties of strawberry fields using principal component analysis

    Directory of Open Access Journals (Sweden)

    Gláucia Oliveira Islabão

    2013-02-01

    Full Text Available One of the largest strawberry-producing municipalities of Rio Grande do Sul (RS is Turuçu, in the South of the State. The strawberry production system adopted by farmers is similar to that used in other regions in Brazil and in the world. The main difference is related to the soil management, which can change the soil chemical properties during the strawberry cycle. This study had the objective of assessing the spatial and temporal distribution of soil fertility parameters using principal component analysis (PCA. Soil sampling was based on topography, dividing the field in three thirds: upper, middle and lower. From each of these thirds, five soil samples were randomly collected in the 0-0.20 m layer, to form a composite sample for each third. Four samples were taken during the strawberry cycle and the following properties were determined: soil organic matter (OM, soil total nitrogen (N, available phosphorus (P and potassium (K, exchangeable calcium (Ca and magnesium (Mg, soil pH (pH, cation exchange capacity (CEC at pH 7.0, soil base (V% and soil aluminum saturation(m%. No spatial variation was observed for any of the studied soil fertility parameters in the strawberry fields and temporal variation was only detected for available K. Phosphorus and K contents were always high or very high from the beginning of the strawberry cycle, while pH values ranged from very low to very high. Principal component analysis allowed the clustering of all strawberry fields based on variables related to soil acidity and organic matter content.

  5. Tungsten Speciation in Firing Range Soils

    Science.gov (United States)

    2011-01-01

    satisfactorily, such as: which tungsten mineral phase is present in soil and to what extent is adsorption important in regu- lating soil solution concentrations... soil solution rather than discrete mineral phases. Information provided in this report will assist the following organizations in future decision...the soil solution ERDC TR-11-1 43 must affect tungsten speciation in other ways. The precipitation of soil minerals also would limit tungsten

  6. Principal chemical properties of artificial soil composed of fly ash and furfural residue

    Energy Technology Data Exchange (ETDEWEB)

    Feng, Y.J.; Li, F.; Wang, X.L.; Liu, X.M.; Zhang, L.N. [Shandong Agricultural University, Tai An (China). College of Resources & Environments

    2006-10-15

    To solve soil shortage in reclaiming subsided land of coal mines, the principal chemical properties of artificial soil formed by mixing organic furfural residue and inorganic fly ash were examined. The results indicated that the artificial soil was suitable for agriculture use after irrigation and desalination, the available nutrients in the artificial soil could satisfy the growth demand of plants, and the pH tended to the neutrality.

  7. Evaluation of skin melanoma in spectral range 450-950 nm using principal component analysis

    Science.gov (United States)

    Jakovels, D.; Lihacova, I.; Kuzmina, I.; Spigulis, J.

    2013-06-01

    Diagnostic potential of principal component analysis (PCA) of multi-spectral imaging data in the wavelength range 450- 950 nm for distant skin melanoma recognition is discussed. Processing of the measured clinical data by means of PCA resulted in clear separation between malignant melanomas and pigmented nevi.

  8. Principal factors of soil spatial heterogeneity and ecosystem services at the Central Chernozemic Region of Russia

    Science.gov (United States)

    Vasenev, Ivan; Valentini, Riccardo

    2013-04-01

    The essential spatial heterogeneity is mutual feature for most natural and man-changed soils at the Central Chernozemic Region of Russia which is not only one of the biggest «food baskets» in RF but very important regulator of ecosystem principal services at the European territory of Russia. The original spatial heterogeneity of dominated here forest-steppe and steppe Chernozems and the other soils has been further complicated by a specific land-use history and different-direction soil successions due to environmental changes and more than 1000-year history of human impacts. The carried out long-term researches of representative natural, rural and urban landscapes in Kursk, Orel, Tambov and Voronezh oblasts give us the regional multi-factorial matrix of elementary soil cover patterns (ESCP) with different land-use practices and history, soil-geomorphologic features, environmental and microclimate conditions. The validation and ranging of the limiting factors of ESCP regulation and development, ecosystem principal services, land functional qualities and agroecological state have been done for dominating and most dynamical components of ESCP regional-typological forms - with application of regional and local GIS, soil spatial patterns mapping, traditional regression kriging, correlation tree models. The outcomes of statistical modeling show the essential amplification of erosion, dehumification and CO2 emission, acidification and alkalization, disaggregation and overcompaction processes due to violation of agroecologically sound land-use systems and traditional balances of organic matter, nutrients, Ca and Na in agrolandscapes. Due to long-term intensive and out-of-balance land-use practices the famous Russian Chernozems begin to lose not only their unique natural features of (around 1 m of humus horizon, 4-6% of Corg and favorable agrophysical features), but traditional soil cover patterns, ecosystem services and agroecological functions. Key-site monitoring

  9. PRINCIPAL COMPONENT ANALYSIS OF FACTORS DETERMINING PHOSPHATE ROCK DISSOLUTION ON ACID SOILS

    Directory of Open Access Journals (Sweden)

    Yusdar Hilman

    2016-10-01

    Full Text Available Many of the agricultural soils in Indonesia are acidic and low in both total and available phosphorus which severely limits their potential for crops production. These problems can be corrected by application of chemical fertilizers. However, these fertilizers are expensive, and cheaper alternatives such as phosphate rock (PR have been considered. Several soil factors may influence the dissolution of PR in soils, including both chemical and physical properties. The study aimed to identify PR dissolution factors and evaluate their relative magnitude. The experiment was conducted in Soil Chemical Laboratory, Universiti Putra Malaysia and Indonesian Center for Agricultural Land Resources Research and Development from January to April 2002. The principal component analysis (PCA was used to characterize acid soils in an incubation system into a number of factors that may affect PR dissolution. Three major factors selected were soil texture, soil acidity, and fertilization. Using the scores of individual factors as independent variables, stepwise regression analysis was performed to derive a PR dissolution function. The factors influencing PR dissolution in order of importance were soil texture, soil acidity, then fertilization. Soil texture factors including clay content and organic C, and soil acidity factor such as P retention capacity interacted positively with P dissolution and promoted PR dissolution effectively. Soil texture factors, such as sand and silt content, soil acidity factors such as pH, and exchangeable Ca decreased PR dissolution.

  10. Phytoextraction of lead from firing range soils with Vetiver grass

    Science.gov (United States)

    E. W. Wilde; R. L. Brigmon; D. L. Dunn; M. A. Heitkamp; D. C. Dagnan

    2007-01-01

    Vetiver grass (Vetiveria zizanoides) along with soil amendments were evaluated for phytoextraction of lead and other metals (zinc, copper, and iron) from the soil of an active firing range at the Savannah River Site, SC. Lead-contaminated soil (300-4,500 ppm/kg) was collected, dried, placed in pots, fertilized, and used as a medium for growing...

  11. Immobilization of lead in shooting range soil using biochar from ...

    African Journals Online (AJOL)

    Spent mushroom substrate (SMS) was pyrolyzed at 450°C for 2 hours and characterized using elemental analyzer and Boehm titration. Shooting range soil was incubated with 2.5% w/w and 5.0% w/w of SMSB for four weeks and the soil were characterized on the elemental composition, pH, electric conductivity (EC) and ...

  12. Soil Compressibility Models for a Wide Stress Range

    KAUST Repository

    Chong, Song-Hun; Santamarina, Carlos

    2016-01-01

    Soil compressibility models with physically correct asymptotic void ratios are required to analyze situations that involve a wide stress range. Previously suggested models and other functions are adapted to satisfy asymptotic void ratios at low

  13. Lead pollution of shooting range soils | Sehube | South African ...

    African Journals Online (AJOL)

    Atotal of eight military shooting ranges were used for this study. Soil samples were collected at each of the eight shooting ranges at the berm, target line, 50 and 100 m from berm. In all of the shooting ranges investigated the highest total lead (Pb) concentrations were found in the bermsoils. Elevated Pb concentrations of 38 ...

  14. Establishing principal soil quality parameters influencing earthworms in urban soils using bioassays

    International Nuclear Information System (INIS)

    Hankard, Peter K.; Bundy, Jacob G.; Spurgeon, David J.; Weeks, Jason M.; Wright, Julian; Weinberg, Claire; Svendsen, Claus

    2005-01-01

    Potential contamination at ex-industrial sites means that, prior to change of use, it will be necessary to quantify the extent of risks to potential receptors. To assess ecological hazards, it is often suggested to use biological assessment to augment chemical analyses. Here we investigate the potential of a commonly recommended bioassay, the earthworm reproduction test, to assess the status of urban contaminated soils. Sample points at all study sites had contaminant concentrations above the Dutch soil criteria Target Values. In some cases, the relevant Intervention Values were exceeded. Earthworm survival at most points was high, but reproduction differed significantly in soil from separate patches on the same site. When the interrelationships between soil parameters and reproduction were studied, it was not possible to create a good model of site soil toxicity based on single or even multiple chemical measurements of the soils. We thus conclude that chemical analysis alone is not sufficient to characterize soil quality and confirms the value of biological assays for risk assessment of potentially contaminated soils. - Bioassays must be applied for the risk assessment complexly-polluted sites to complement chemical analysis of soils

  15. Soil Compressibility Models for a Wide Stress Range

    KAUST Repository

    Chong, Song-Hun

    2016-03-03

    Soil compressibility models with physically correct asymptotic void ratios are required to analyze situations that involve a wide stress range. Previously suggested models and other functions are adapted to satisfy asymptotic void ratios at low and high stress levels; all updated models involve four parameters. Compiled consolidation data for remolded and natural clays are used to test the models and to develop correlations between model parameters and index properties. Models can adequately fit soil compression data for a wide range of stresses and soil types; in particular, models that involve the power of the stress σ\\'β display higher flexibility to capture the brittle response of some natural soils. The use of a single continuous function avoids numerical discontinuities or the need for ad hoc procedures to determine the yield stress. The tangent stiffness-readily computed for all models-should not be mistaken for the small-strain constant-fabric stiffness. © 2016 American Society of Civil Engineers.

  16. Detecting 3-D rotational motion and extracting target information from the principal component analysis of scatterer range histories

    CSIR Research Space (South Africa)

    Nel, W

    2009-10-01

    Full Text Available to estimate the 3-D position of scatterers as a by-product of the analysis. The technique is based on principal component analysis of accurate scatterer range histories and is shown only in simulation. Future research should focus on practical application....

  17. Long-range alpha detection applied to soil surface monitoring

    International Nuclear Information System (INIS)

    Caress, R.W.; Allander, K.S.; Bounds, J.A.; Catlett, M.M.; MacArthur, D.W.; Rutherford, D.A.

    1992-01-01

    The long-range alpha detection (LRAD) technique depends on the detection of ion pairs generated by alpha particles losing energy in air rather than on detection of the alpha particles themselves. Typical alpha particles generated by uranium will travel less than 3 cm in air. In contrast, the ions have been successfully detected many inches or feet away from the contamination. Since LRAD detection systems are sensitive to all ions simultaneously, large LRAD soil surface monitors (SSMS) can be used to collect all of the ions from a large sample. The LRAD SSMs are designed around the fan-less LRAD detector. In this case a five-sided box with an open bottom is placed on the soil surface. Ions generated by alpha decays on the soil surface are collected on a charged copper plate within the box. These ions create a small current from the plate to ground which is monitored with a sensitive electrometer. The current measured is proportional to the number of ions in the box, which is, in turn, proportional to the amount of alpha contamination on the surface of the soil. This report includes the design and construction of a 1-m by 1-m SSM as well as the results of a study at Fernald, OH, as part of the Uranium in Soils Integrated Demonstration

  18. Evaluation of Soil Loss and Erosion Control Measures on Ranges and Range Structures at Installations in Temperate Climates

    Science.gov (United States)

    2006-06-01

    Soil Loss Equation ( USLE ) and the Revised Universal Soil Loss Equation (RUSLE) continue to be widely accepted methods for estimating sediment loss...range areas. Therefore, a generalized design methodology using the Universal Soil Loss Equation ( USLE ) is presented to accommodate the variations...constructed use the slope most suitable to the area topography (3:1 or 4:1). Step 4: Using the Universal Soil Loss equation, USLE , find the values of A

  19. Classification of soil samples according to their geographic origin using gamma-ray spectrometry and principal component analysis

    International Nuclear Information System (INIS)

    Dragovic, Snezana; Onjia, Antonije

    2006-01-01

    A principal component analysis (PCA) was used for classification of soil samples from different locations in Serbia and Montenegro. Based on activities of radionuclides ( 226 Ra, 238 U, 235 U, 4 K, 134 Cs, 137 Cs, 232 Th and 7 Be) detected by gamma-ray spectrometry, the classification of soils according to their geographical origin was performed. Application of PCA to our experimental data resulted in satisfactory classification rate (86.0% correctly classified samples). The obtained results indicate that gamma-ray spectrometry in conjunction with PCA is a viable tool for soil classification

  20. Independent principal component analysis for simulation of soil water content and bulk density in a Canadian Watershed

    Directory of Open Access Journals (Sweden)

    Alaba Boluwade

    2016-09-01

    Full Text Available Accurate characterization of soil properties such as soil water content (SWC and bulk density (BD is vital for hydrologic processes and thus, it is importance to estimate θ (water content and ρ (soil bulk density among other soil surface parameters involved in water retention and infiltration, runoff generation and water erosion, etc. The spatial estimation of these soil properties are important in guiding agricultural management decisions. These soil properties vary both in space and time and are correlated. Therefore, it is important to find an efficient and robust technique to simulate spatially correlated variables. Methods such as principal component analysis (PCA and independent component analysis (ICA can be used for the joint simulations of spatially correlated variables, but they are not without their flaws. This study applied a variant of PCA called independent principal component analysis (IPCA that combines the strengths of both PCA and ICA for spatial simulation of SWC and BD using the soil data set from an 11 km2 Castor watershed in southern Quebec, Canada. Diagnostic checks using the histograms and cumulative distribution function (cdf both raw and back transformed simulations show good agreement. Therefore, the results from this study has potential in characterization of water content variability and bulk density variation for precision agriculture.

  1. Soil bacteria show different tolerance ranges to an unprecedented disturbance

    NARCIS (Netherlands)

    Nunes, Ines; Jurburg, Stephanie; Jacquiod, Samuel; Brejnrod, Asker; Salles, Joana Falcao; Prieme, Anders; Sorensen, Soren J.

    Soil microbial communities have remarkable capacities to cope with ceaseless environmental changes, but little is known about their adaptation potential when facing an unprecedented disturbance. We tested the effect of incremental dose of microwaving on soil bacteria as a model of unprecedented

  2. Modeling soil evaporation efficiency in a range of soil and atmospheric conditions using a meta-analysis approach

    OpenAIRE

    Merlin , O; Stefan , V ,; Amazirh , A; Chanzy , A; Ceschia , E; Er-Raki , S; Gentine , P; Tallec , T; Ezzahar , J; Bircher , S; Beringer , J; Khabba , S

    2016-01-01

    International audience; A meta-analysis data-driven approach is developed to represent the soil evaporative efficiency (SEE) defined as the ratio of actual to potential soil evaporation. The new model is tested across a bare soil database composed of more than 30 sites around the world, a clay fraction range of 0.02-0.56, a sand fraction range of 0.05-0.92, and about 30,000 acquisition times. SEE is modeled using a soil resistance ($r_{ss}$) formulation based on surface soil moisture ($\\theta...

  3. Characterization of contaminated soil and groundwater surrounding an illegal landfill (S. Giuliano, Venice, Italy) by principal component analysis and kriging

    International Nuclear Information System (INIS)

    Critto, Andrea; Carlon, Claudio; Marcomini, Antonio

    2003-01-01

    Information on soil and groundwater contamination was used to develop a site conceptual model and to identify exposure scenarios. - The characterization of a hydrologically complex contaminated site bordering the lagoon of Venice (Italy) was undertaken by investigating soils and groundwaters affected by the chemical contaminants originated by the wastes dumped into an illegal landfill. Statistical tools such as principal components analysis and geostatistical techniques were applied to obtain the spatial distribution of chemical contaminants. Dissolved organic carbon (DOC), SO 4 2- and Cl - were used to trace the migration of the contaminants from the top soil to the underlying groundwaters. The chemical and hydrogeological available information was assembled to obtain the schematic of the conceptual model of the contaminated site capable to support the formulation of major exposure scenarios, which are also provided

  4. Electrokinetic treatment of firing ranges containing tungsten-contaminated soils

    International Nuclear Information System (INIS)

    Braida, Washington; Christodoulatos, Christos; Ogundipe, Adebayo; Dermatas, Dimitris; O'Connor, Gregory

    2007-01-01

    Tungsten-based alloys and composites are being used and new formulations are being considered for use in the manufacturing of different types of ammunition. The use of tungsten heavy alloys (WHA) in new munitions systems and tungsten composites in small caliber ammunition could potentially release substantial amounts of this element into the environment. Although tungsten is widely used in industrial and military applications, tungsten's potential environmental and health impacts have not been thoroughly addressed. This necessitates the research and development of remedial technologies to contain and/or remove tungsten from soils that may serve as a source for water contamination. The current work investigates the feasibility of using electrokinetics for the remediation of tungsten-contaminated soils in the presence of other heavy metals of concern such as Cu and Pb with aim to removing W from the soil while stabilizing in situ, Pb and Cu

  5. Lithosequence of soils and associated vegetation on subalpine range of the Wasatch Plateau, Utah.

    Science.gov (United States)

    James O. Klemmedson; Arthur R. Tiedemann

    1998-01-01

    On degraded subalpine range in Utah, the authors examined the role of soil and parent material nutrients and organic carbon (Corg) in the development of soil and plants on a transect across six strata that formed visible concentric alternating bands of high and low productivity. Relations for soil and parent material phosphorus (P) and sulfur (S) were of particular...

  6. Permissiveness of soil microbial communities towards broad host range plasmids

    DEFF Research Database (Denmark)

    Klümper, Uli

    . Plasmids are implicated in the rapid spread of antibiotic resistance and the emergence of multi-resistant pathogenic bacteria, making it crucial to be able to quantify, understand, and, ideally, control plasmid transfer in mixed microbial communities. The fate of plasmids in microbial communities...... of microbial communities may be directly interconnected through transfer of BHR plasmids at a so far unrecognized level. The developed method furthermore enabled me to explore how agronomic practices may affect gene transfer in soil microbial communities. I compared bacterial communities extracted from plots...

  7. Componentes principais como preditores no mapeamento digital de classes de solos Principal components as predictor variables in digital mapping of soil classes

    Directory of Open Access Journals (Sweden)

    Alexandre ten Caten

    2011-07-01

    Full Text Available Tecnologias disponíveis para a observação da Terra oferecem uma grande gama de informações sobre componentes ambientais que, por estarem relacionadas com a formação dos solos, podem ser usadas como variáveis preditoras no Mapeamento Digital de Solos (MDS. No entanto, modelos com um grande número de preditores, bem como a existência de multicolinearidade entre os dados, podem ser ineficazes no mapeamento de classes e propriedades do solo. O objetivo deste estudo foi empregar a Análise de Componentes Principais (ACP visando a selecionar e diminuir o número de preditores na regressão logística múltipla multinomial (RLMM utilizada no mapeamento de classes de solos. Nove covariáveis ambientais, ligadas ao fator de formação relevo, foram derivadas de um Modelo Digital de Elevação e denominadas variáveis originais, estas foram submetidas à ACP e transformadas em Componentes Principais (CP. As RLMM foram desenvolvidas utilizando-se atributos de terreno e as CP como variáveis explicativas. O mapa de solos gerado a partir de três CP (65,6% da variância original obteve um índice kappa de 37,3%, inferior aos 48,5% alcançado pelo mapa de solos gerado a partir de todas as nove variáveis originais.Available technologies for Earth observation offer a wide range of predictors relevant to Digital Soil Mapping (DSM. However, models with a large number of predictors, as well as, the existence of multicollinearity among the data, may be ineffective in the mapping of classes and soil properties. The aim of this study was to use the Principal Component Analysis (PCA to reduce the number of predictors in the multinomial logistic regression (MLR used in soil mapping. Nine environmental covariates, related to the relief factor of soil formation, were derived from a digital elevation model and named the original variables, which were submitted to PCA and transformed into principal components (PC. The MLR were developed using the terrain

  8. The relationship between brightness temperature and soil moisture. Selection of frequency range for microwave remote sensing

    International Nuclear Information System (INIS)

    Rao, K.S.; Chandra, G.; Rao, P.V.N.

    1987-01-01

    The analysis of brightness temperature data acquired from field and aircraft experiments demonstrates a linear relationship between soil moisture and brightness temperature. However, the analysis of brightness temperature data acquired by the Skylab radiometer demonstrates a non-linear relationship between soil moisture and brightness temperature. In view of the above and also because of recent theoretical developments for the calculation of the dielectric constant and brightness temperature under varying soil moisture profile conditions, an attempt is made to study the theoretical relationship between brightness temperature and soil moisture as a function of frequency. Through the above analysis, the appropriate microwave frequency range for soil moisture studies is recommended

  9. Assessment of Soil-Gas and Soil Contamination at the Former Military Police Range, Fort Gordon, Georgia, 2009-2010

    Science.gov (United States)

    Falls, W. Fred; Caldwell, Andral W.; Guimaraes, Wladmir B.; Ratliff, W. Hagan; Wellborn, John B.; Landmeyer, James E.

    2011-01-01

    Soil gas and soil were assessed for organic and inorganic contaminants at the former military police range at Fort Gordon, Georgia, from May to September 2010. The assessment evaluated organic contaminants in soil-gas samplers and inorganic contaminants in soil samples. This assessment was conducted to provide environmental contamination data to Fort Gordon pursuant to requirements of the Resource Conservation and Recovery Act Part B Hazardous Waste Permit process. Soil-gas samplers deployed and collected from May 20 to 24, 2010, identified masses above method detection level for total petroleum hydrocarbons, gasoline-related and diesel-related compounds, and chloroform. Most of these detections were in the southwestern quarter of the study area and adjacent to the road on the eastern boundary of the site. Nine of the 11 chloroform detections were in the southern half of the study area. One soil-gas sampler deployed adjacent to the road on the southern boundary of the site detected a mass of tetrachloroethene greater than, but close to, the method detection level of 0.02 microgram. For soil-gas samplers deployed and collected from September 15 to 22, 2010, none of the selected organic compounds classified as chemical agents and explosives were detected above method detection levels. Inorganic concentrations in the five soil samples collected at the site did not exceed the U.S. Environmental Protection Agency regional screening levels for industrial soil and were at or below background levels for similar rocks and strata in South Carolina.

  10. Soil feedback and pathogen activity in Prunus serotina throughout its native range

    Science.gov (United States)

    Kurt O. Reinhart; Alejandro Royo; Wim H. Van der Putten; Keith Clay

    2005-01-01

    1 Oomycete soil pathogens are known to have a negative effect on Prunus serotina seedling establishment and to promote tree diversity in a deciduous forest in Indiana, USA. Here, we investigate whether negative feedbacks operate widely in its native range in eastern USA. 2 In laboratory experiments, soil sterilization was used to test the...

  11. The Value Range of Contact Stiffness Factor between Pile and Soil Based on Penalty Function

    Science.gov (United States)

    Chen, Sandy H. L.; Wu, Xinliu

    2018-03-01

    The value range of contact stiffness factor based on penalty function is studied when we use finite element software ANSYS to analyze contact problems, take single pile and soil of a certain project for example, the normal contact between pile and soil is analyzed with 2D simplified model in horizontal load. The study shows that when adopting linear elastic model to simulate soil, the maximum contact pressure and penetration approach steady value as the contact stiffness factor increases. The reasonable value range of contact stiffness factor reduces as the underlying element thickness decreases, but the rule reverses when refers to the soil stiffness. If choose DP model to simulate soil, the stiffness factor should be magnified 100 times compares to the elastic model regardless of the soil bears small force and still in elastic deformation stage or into the plastic deformation stage. When the soil bears big force and into plastic deformation stage, the value range of stiffness factor relates to the plastic strain range of the soil, and reduces as the horizontal load increases.

  12. Analysis of factors controlling soil phosphorus loss with surface runoff in Huihe National Nature Reserve by principal component and path analysis methods.

    Science.gov (United States)

    He, Jing; Su, Derong; Lv, Shihai; Diao, Zhaoyan; Bu, He; Wo, Qiang

    2018-01-01

    Phosphorus (P) loss with surface runoff accounts for the P input to and acceleration of eutrophication of the freshwater. Many studies have focused on factors affecting P loss with surface runoff from soils, but rarely on the relationship among these factors. In the present study, rainfall simulation on P loss with surface runoff was conducted in Huihe National Nature Reserve, in Hulunbeier grassland, China, and the relationships between P loss with surface runoff, soil properties, and rainfall conditions were examined. Principal component analysis and path analysis were used to analyze the direct and indirect effects on P loss with surface runoff. The results showed that P loss with surface runoff was closely correlated with soil electrical conductivity, soil pH, soil Olsen P, soil total nitrogen (TN), soil total phosphorus (TP), and soil organic carbon (SOC). The main driving factors which influenced P loss with surface runoff were soil TN, soil pH, soil Olsen P, and soil water content. Path analysis and determination coefficient analysis indicated that the standard multiple regression equation for P loss with surface runoff and each main factor was Y = 7.429 - 0.439 soil TN - 6.834 soil pH + 1.721 soil Olsen-P + 0.183 soil water content (r = 0.487, p runoff. The effect of physical and chemical properties of undisturbed soils on P loss with surface runoff was discussed, and the soil water content and soil Olsen P were strongly positive influences on the P loss with surface runoff.

  13. Plant-soil interactions in the expansion and native range of a poleward shifting plant species

    NARCIS (Netherlands)

    Grunsven, van R.H.A.; Putten, van der W.H.; Bezemer, T.M.; Berendse, F.; Veenendaal, E.M.

    2010-01-01

    Climate warming causes range shifts of many species toward higher latitudes and altitudes. However, range shifts of host species do not necessarily proceed at the same rates as those of their enemies and symbionts. Here, we examined how a range shifting plant species performs in soil from its

  14. Plant–soil interactions in the expansion and native range of a poleward shifting plant species

    NARCIS (Netherlands)

    Van Grunsven, R.H.A.; Van der Putten, W.H.; Bezemer, T.M.; Berendse, F.; Veenendaal, E.M.

    2010-01-01

    Climate warming causes range shifts of many species toward higher latitudes and altitudes. However, range shifts of host species do not necessarily proceed at the same rates as those of their enemies and symbionts. Here, we examined how a range shifting plant species performs in soil from its

  15. Quantifying Cr(VI) Production and Export from Serpentine Soil of the California Coast Range.

    Science.gov (United States)

    McClain, Cynthia N; Fendorf, Scott; Webb, Samuel M; Maher, Kate

    2017-01-03

    Hexavalent chromium (Cr(VI)) is generated in serpentine soils and exported to surface and groundwaters at levels above health-based drinking water standards. Although Cr(VI) concentrations are elevated in serpentine soil pore water, few studies have reported field evidence documenting Cr(VI) production rates and fluxes that govern Cr(VI) transport from soil to water sources. We report Cr speciation (i) in four serpentine soil depth profiles derived from the California Coast Range serpentinite belt and (ii) in local surface waters. Within soils, we detected Cr(VI) in the same horizons where Cr(III)-minerals are colocated with biogenic Mn(III/IV)-oxides, suggesting Cr(VI) generation through oxidation by Mn-oxides. Water-extractable Cr(VI) concentrations increase with depth constituting a 7.8 to 12 kg/km 2 reservoir of Cr(VI) in soil. Here, Cr(VI) is produced at a rate of 0.3 to 4.8 kg Cr(VI)/km 2 /yr and subsequently flushed from soil during water infiltration, exporting 0.01 to 3.9 kg Cr(VI)/km 2 /yr at concentrations ranging from 25 to 172 μg/L. Although soil-derived Cr(VI) is leached from soil at concentrations exceeding 10 μg/L, due to reduction and dilution during transport to streams, Cr(VI) levels measured in local surface waters largely remain below California's drinking water limit.

  16. Soil pollution at outdoor shooting ranges: Health effects, bioavailability and best management practices.

    Science.gov (United States)

    Fayiga, A O; Saha, U K

    2016-09-01

    The total lead (Pb) concentrations of the surface soil, sub surface soil, vegetation and surface waters of outdoor shooting ranges are extremely high and above regulatory limits. Lead is dangerous at high concentrations and can cause a variety of serious health problems. Shooters and range workers are exposed to lead dust and can even take Pb dust home to their families while some animals around the shooting range can ingest the Pb bullets. The toxicity of Pb depends on its bioavailability which has been determined to be influenced greatly by the geochemical properties of each site. The bioavailability of Pb in shooting ranges has been found to be higher than other metal contaminated soils probably because of its very low residual Pb (soil, migration of Pb within shooting ranges and offsite has been reported in literature. Best management practices to reduce mobility of Pb in shooting ranges involve an integrated Pb management program which has been described in the paper. The adoption of the non-toxic "green bullet" which has been developed to replace Pb bullets may reduce or prevent environmental pollution at shooting ranges. However, the contaminated soil resulting from decades of operation of several shooting ranges still needs to be restored to its natural state. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. Immobilization of lead in shooting range soils by means of cement, quicklime, and phosphate amendments.

    Science.gov (United States)

    Cao, Xinde; Dermatas, Dimitris; Xu, Xuanfeng; Shen, Gang

    2008-03-01

    Lead (Pb) contamination at shooting range sites is increasingly under environmental concern. Controlling Pb leachability from shooting range soil media is an important step to minimize Pb exposure to the surrounding environment. This study investigated stabilization of Pb in shooting range soils treated with cement, quicklime, and phosphate. Two soils were used and collected from two shooting ranges, referred to as SR1 and SR2. The treatment additives were applied to the soils at rates from 2.5% to 10% (w/w). The effectiveness of each treatment was evaluated by Pb (w/w). The effectiveness of each treatment was evaluated by Pb leachability, measured by the Toxicity Characteristic Leaching Procedure (TCLP). The possible mechanisms for Pb immobilization were elucidated using X-ray powder diffraction (XRPD). Cement and quicklime treatments were effective in immobilizing Pb in SR1 soil, with reduction of Pb concentration in TCLP leachate (TCLP-Pb) to be below the U.S. EPA non-hazardous regulatory limit of 5 mg L(-1) at application rates of > or =5% and 28-d incubation. By contrast, cement and quicklime amendments were less effective for Pb stabilization in SR2 soil because the TCLP-Pb levels in the treated soil were still higher than the limit of 5 mg L(-1) at all application rates, although they were significantly reduced in comparison with the untreated soil. Phosphate application was most effective in reducing Pb leach ing in both soils. Even at an application rate as low as 5% and 1-d incubation, phosphate could reduce TCLP-Pb to be below the limit of 5 mg L(-1) in both soils. Immobilization of Pb in the SR1 soil amended with cement and quicklime was attributed to the formation of pozzolanic minerals (e.g., calcium silicate hydrate C-S-H and ettringite) that could encapsulate soil Pb. The pozzolanic reaction was limited in the SR2 soil upon the application of cement and quicklime. Reduction of the TCLP-Pb might result from complexation of Pb on the surface of the

  18. Soil moisture datasets at five sites in the central Sierra Nevada and northern Coast Ranges, California

    Science.gov (United States)

    Stern, Michelle A.; Anderson, Frank A.; Flint, Lorraine E.; Flint, Alan L.

    2018-05-03

    In situ soil moisture datasets are important inputs used to calibrate and validate watershed, regional, or statewide modeled and satellite-based soil moisture estimates. The soil moisture dataset presented in this report includes hourly time series of the following: soil temperature, volumetric water content, water potential, and total soil water content. Data were collected by the U.S. Geological Survey at five locations in California: three sites in the central Sierra Nevada and two sites in the northern Coast Ranges. This report provides a description of each of the study areas, procedures and equipment used, processing steps, and time series data from each site in the form of comma-separated values (.csv) tables.

  19. A network of experimental forests and ranges: Providing soil solutions for a changing world

    Science.gov (United States)

    Mary Beth. Adams

    2010-01-01

    The network of experimental forests and ranges of the USDA Forest Service represents significant opportunities to provide soil solutions to critical issues of a changing world. This network of 81 experimental forests and ranges encompasses broad geographic, biological, climatic and physical scales, and includes long-term data sets, and long-term experimental...

  20. Solvent extraction treatment of PCB contaminated soil at Sparrevohn Long Range Radar Station, Alaska

    International Nuclear Information System (INIS)

    Weimer, L. D.

    1999-01-01

    On-site soil treatment at a long range radar station in Alaska, which was contaminated with between 50 and 350 mg/kg of polychlorinated biphenyls (PCBs) is described. The stock-piled soil was treated by the Terra Kleen Response Group, using a solvent extraction process. After the treatment, PCB concentrations in the treated soil were found to have been reduced to less than the target treatment level of 15 mg/kg. Not only was the process successful, it also saved the government about $ 1 million over what hauling and off-site treatment and disposal would have cost. 1 tab

  1. Lead pollution of soil and groundwater in clay-pigeon shooting ranges

    International Nuclear Information System (INIS)

    Hahn, R.

    1990-01-01

    Within the framework of the exemplary investigation of soil and groundwater pollution with lead on clay-pigeon shooting ranges, three facilities were sampled. The analyses for depth distribution in the main area of the ammunition deposition showed that the dissolved lead amounts are as a rule smaller than the limiting value of the Sewage Sludge Regulation (100 mg/kg). In two groundwater samples, no lead could be found. Considerable amounts of small lead balls are found on the soil surface, but only a very small part appears to be washed out and adsorbed by the soil matrix. (orig.) [de

  2. The effects of heavy metal contamination on the soil arthropod community of a shooting range

    International Nuclear Information System (INIS)

    Migliorini, Massimo; Pigino, Gaia; Bianchi, Nicola; Bernini, Fabio; Leonzio, Claudio

    2004-01-01

    Soils in clay pigeon shooting ranges can be seriously contaminated by heavy metals. The pellets contained in ammunition are composed of Pb, Sb, Ni, Zn, Mn and Cu. The total concentrations of these metals in soils, and the effects of their increasing levels on the arthropod community were investigated at seven sampling sites in a clay pigeon shooting range and compared with two controls. Research revealed that the spatial distribution of Pb and Sb contamination in the shot-fall area was strongly correlated with the flight path of the pellets. Ordination obtained through Redundance Analysis showed that Collembola, Protura and Diplura were positively correlated with major detected contaminants (Pb, Sb), while Symphyla showed a negative correlation with these pollutants. Determination of the soluble lead fraction in soil, and of its bioaccumulation in the saprophagous Armadillidium sordidum (Isopoda) and the predator Ocypus olens (Coleoptera), showed that a significant portion of metallic Pb from spent pellets is bioavailable in the soil and can be bioaccumulated by edaphic organisms, entering the soil trophic network, but without biomagnification. - Significant relationships were found between lead accumulation in soil from a shooting range and inhabiting arthropod communities

  3. Tree species and soil nutrient profiles in old-growth forests of the Oregon Coast Range

    Science.gov (United States)

    Cross, Alison; Perakis, Steven S.

    2011-01-01

    Old-growth forests of the Pacific Northwest provide a unique opportunity to examine tree species – soil relationships in ecosystems that have developed without significant human disturbance. We characterized foliage, forest floor, and mineral soil nutrients associated with four canopy tree species (Douglas-fir (Pseudotsuga menziesii (Mirbel) Franco), western hemlock (Tsuga heterophylla (Raf.) Sarg.), western redcedar (Thuja plicata Donn ex D. Don), and bigleaf maple (Acer macrophyllum Pursh)) in eight old-growth forests of the Oregon Coast Range. The greatest forest floor accumulations of C, N, P, Ca, Mg, and K occurred under Douglas-fir, primarily due to greater forest floor mass. In mineral soil, western hemlock exhibited significantly lower Ca concentration and sum of cations (Ca + Mg + K) than bigleaf maple, with intermediate values for Douglas-fir and western redcedar. Bigleaf maple explained most species-based differences in foliar nutrients, displaying high concentrations of N, P, Ca, Mg, and K. Foliar P and N:P variations largely reflected soil P variation across sites. The four tree species that we examined exhibited a number of individualistic effects on soil nutrient levels that contribute to biogeochemical heterogeneity in these ecosystems. Where fire suppression and long-term succession favor dominance by highly shade-tolerant western hemlock, our results suggest a potential for declines in both soil Ca availability and soil biogeochemical heterogeneity in old-growth forests.

  4. Chinese tallow trees (Triadica sebifera) from the invasive range outperform those from the native range with an active soil community or phosphorus fertilization.

    Science.gov (United States)

    Zhang, Ling; Zhang, Yaojun; Wang, Hong; Zou, Jianwen; Siemann, Evan

    2013-01-01

    Two mechanisms that have been proposed to explain success of invasive plants are unusual biotic interactions, such as enemy release or enhanced mutualisms, and increased resource availability. However, while these mechanisms are usually considered separately, both may be involved in successful invasions. Biotic interactions may be positive or negative and may interact with nutritional resources in determining invasion success. In addition, the effects of different nutrients on invasions may vary. Finally, genetic variation in traits between populations located in introduced versus native ranges may be important for biotic interactions and/or resource use. Here, we investigated the roles of soil biota, resource availability, and plant genetic variation using seedlings of Triadica sebifera in an experiment in the native range (China). We manipulated nitrogen (control or 4 g/m(2)), phosphorus (control or 0.5 g/m(2)), soil biota (untreated or sterilized field soil), and plant origin (4 populations from the invasive range, 4 populations from the native range) in a full factorial experiment. Phosphorus addition increased root, stem, and leaf masses. Leaf mass and height growth depended on population origin and soil sterilization. Invasive populations had higher leaf mass and growth rates than native populations did in fresh soil but they had lower, comparable leaf mass and growth rates in sterilized soil. Invasive populations had higher growth rates with phosphorus addition but native ones did not. Soil sterilization decreased specific leaf area in both native and exotic populations. Negative effects of soil sterilization suggest that soil pathogens may not be as important as soil mutualists for T. sebifera performance. Moreover, interactive effects of sterilization and origin suggest that invasive T. sebifera may have evolved more beneficial relationships with the soil biota. Overall, seedlings from the invasive range outperformed those from the native range, however

  5. Comparative evaluation of phytoremediation of metal contaminated soil of firing range by four different plant species

    Directory of Open Access Journals (Sweden)

    Saadia R. Tariq

    2016-11-01

    Full Text Available The phytoremediation potential of Helianthus annuus, Zea maize, Brassica campestris and Pisum sativum was studied for the soil of firing range contaminated with selected metals i.e. Cd, Cu, Co, Ni, Cr and Pb. The seedlings of the selected plants germinated in a mixture of sand and alluvial soil were transferred to the pots containing the soil of firing ranges and allowed to grow to the stage of reproductive growth. Subsequently they were harvested and then analyzed for selected metals by using AAS. Among the studied plants, P. sativum exhibited highest removal efficiency (i.e. 96.23% and bioconcentration factor for Pb thereby evidencing it to be Pb hyperaccumulator from the soil of firing ranges. Z. maize appreciably reduced the levels of all the selected metals in the soil but the highest phytoextraction capacity was shown for Pb i.e. 66.36%, which was enhanced to approximately 74% on EDTA application. H. annuus represented the highest removal potential for Cd i.e. 56.03% which was further increased on EDTA application. Thus it proved to be an accumulator of Cd after EDTA application. It was therefore concluded that different plants possess different phytoremediation potentials under given set of conditions.

  6. Modeling soil evaporation efficiency in a range of soil and atmospheric conditions using a meta-analysis approach

    Science.gov (United States)

    Merlin, O.; Stefan, V. G.; Amazirh, A.; Chanzy, A.; Ceschia, E.; Er-Raki, S.; Gentine, P.; Tallec, T.; Ezzahar, J.; Bircher, S.; Beringer, J.; Khabba, S.

    2016-05-01

    A meta-analysis data-driven approach is developed to represent the soil evaporative efficiency (SEE) defined as the ratio of actual to potential soil evaporation. The new model is tested across a bare soil database composed of more than 30 sites around the world, a clay fraction range of 0.02-0.56, a sand fraction range of 0.05-0.92, and about 30,000 acquisition times. SEE is modeled using a soil resistance (rss) formulation based on surface soil moisture (θ) and two resistance parameters rss,ref and θefolding. The data-driven approach aims to express both parameters as a function of observable data including meteorological forcing, cut-off soil moisture value θ1/2 at which SEE=0.5, and first derivative of SEE at θ1/2, named Δθ1/2-1. An analytical relationship between >(rss,ref;θefolding) and >(θ1/2;Δθ1/2-1>) is first built by running a soil energy balance model for two extreme conditions with rss = 0 and rss˜∞ using meteorological forcing solely, and by approaching the middle point from the two (wet and dry) reference points. Two different methods are then investigated to estimate the pair >(θ1/2;Δθ1/2-1>) either from the time series of SEE and θ observations for a given site, or using the soil texture information for all sites. The first method is based on an algorithm specifically designed to accomodate for strongly nonlinear SEE>(θ>) relationships and potentially large random deviations of observed SEE from the mean observed SEE>(θ>). The second method parameterizes θ1/2 as a multi-linear regression of clay and sand percentages, and sets Δθ1/2-1 to a constant mean value for all sites. The new model significantly outperformed the evaporation modules of ISBA (Interaction Sol-Biosphère-Atmosphère), H-TESSEL (Hydrology-Tiled ECMWF Scheme for Surface Exchange over Land), and CLM (Community Land Model). It has potential for integration in various land-surface schemes, and real calibration capabilities using combined thermal and microwave

  7. Stabilizing lead bullets in shooting range soil by phosphate-based surface coating

    Directory of Open Access Journals (Sweden)

    Bin Hua

    2016-08-01

    Full Text Available Soil lead (Pb is well known as a threat to human health and ecosystem. Although relatively insoluble, lead bullets in shooting range soil can be readily released into soluble forms through natural weathering processes and thus pose significant human and environmental risks. In this study, laboratory experiments were conducted to investigate if the Pb bullets in shooting range soil can be stabilized through surface coating of phosphate-based materials. Results indicated that FePO4 or AlPO4 coatings, insoluble metal phosphates, have been successfully formed on the surface of the Pb bullets. The EPA Toxicity Characteristic Leaching Procedure (TCLP test showed that FePO4 or AlPO4 surface coating would effectively reduce the Pb solubility or leachability of the bullets. The surface coating under pH of <5.5 for 7 days could achieve 92–100% reduction, with 85–98% by FePO4 coating and 77–98% by AlPO4 coating as compared with the non-coating. Leachable Pb concentration in the contaminated shooting range soil was reduced by 85–98% or 77–98% as a result of the FePO4 or AlPO4 solution treatment. This study demonstrated that the FePO4 or AlPO4–based surface coating on lead bullets can effectively inhibit the Pb weathering and significantly reduce the Pb release from soil through in situ chemical stabilization, which could be potentially applicable as a cost-effective and environmental-sound technology for the remediation of Pb-contaminated shooting range soil.

  8. Plant host range of Verticillium longisporum and microsclerotia density in Swedisch soils

    NARCIS (Netherlands)

    Johansson, A.; Goud, J.C.; Dixelius, C.

    2006-01-01

    Verticillium longisporum is a soil-borne fungal pathogen causing vascular wilt of Brassica crops. This study was conducted to enhance our knowledge on the host range of V. longisporum. Seven crop species (barley, oat, oilseed rape, pea, red clover, sugar beet and wheat) and five weed species (barren

  9. Least limiting water range of Udox soil under degraded pastures on different sun-exposed faces

    Science.gov (United States)

    Passos, Renato Ribeiro; Marciano da Costa, Liovando; Rodrigues de Assis, Igor; Santos, Danilo Andrade; Ruiz, Hugo Alberto; Guimarães, Lorena Abdalla de Oliveira Prata; Andrade, Felipe Vaz

    2017-07-01

    The efficient use of water is increasingly important and proper soil management, within the specificities of each region of the country, allows achieving greater efficiency. The South and Caparaó regions of Espírito Santo, Brazil are characterized by relief of `hill seas' with differences in the degree of pasture degradation due to sun exposure. The objective of this study was to evaluate the least limiting water range in Udox soil under degraded pastures with two faces of exposure to the sun and three pedoenvironments. In each pedoenvironment, namely Alegre, Celina, and Café, two areas were selected, one with exposure on the North/West face and the other on the South/East face. In each of these areas, undisturbed soil samples were collected at 0-10 cm depth to determine the least limiting water range. The exposed face of the pasture that received the highest solar incidence (North/West) presented the lowest values in least limiting water range. The least limiting water range proved to be a physical quality indicator for Udox soil under degraded pastures.

  10. Soil feedback and pathogen activity in Prunus serotina throughout its native range

    NARCIS (Netherlands)

    Reinhart, K.O.; Royo, A.A.; Putten, van der W.H.; Clay, K.

    2005-01-01

    1 Oomycete soil pathogens are known to have a negative effect on Prunus serotina seedling establishment and to promote tree diversity in a deciduous forest in Indiana, USA. Here, we investigate whether negative feedbacks operate widely in its native range in eastern USA. 2 In laboratory experiments,

  11. Parametric soil water retention models: a critical evaluation of expressions for the full moisture range

    Science.gov (United States)

    Madi, Raneem; Huibert de Rooij, Gerrit; Mielenz, Henrike; Mai, Juliane

    2018-02-01

    Few parametric expressions for the soil water retention curve are suitable for dry conditions. Furthermore, expressions for the soil hydraulic conductivity curves associated with parametric retention functions can behave unrealistically near saturation. We developed a general criterion for water retention parameterizations that ensures physically plausible conductivity curves. Only 3 of the 18 tested parameterizations met this criterion without restrictions on the parameters of a popular conductivity curve parameterization. A fourth required one parameter to be fixed. We estimated parameters by shuffled complex evolution (SCE) with the objective function tailored to various observation methods used to obtain retention curve data. We fitted the four parameterizations with physically plausible conductivities as well as the most widely used parameterization. The performance of the resulting 12 combinations of retention and conductivity curves was assessed in a numerical study with 751 days of semiarid atmospheric forcing applied to unvegetated, uniform, 1 m freely draining columns for four textures. Choosing different parameterizations had a minor effect on evaporation, but cumulative bottom fluxes varied by up to an order of magnitude between them. This highlights the need for a careful selection of the soil hydraulic parameterization that ideally does not only rely on goodness of fit to static soil water retention data but also on hydraulic conductivity measurements. Parameter fits for 21 soils showed that extrapolations into the dry range of the retention curve often became physically more realistic when the parameterization had a logarithmic dry branch, particularly in fine-textured soils where high residual water contents would otherwise be fitted.

  12. Assessment of Sampling Error Associated with Collection and Analysis of Soil Samples at a Firing Range Contaminated with HMX

    National Research Council Canada - National Science Library

    Jenkins, Thomas F

    1997-01-01

    Short-range and mid-range (grid size) spatial heterogeneity in explosives concentrations within surface soils was studied at an active antitank firing range at the Canadian Force Base-Valcartier, Val-Belair, Quebec...

  13. Chemical stabilisation of lead in shooting range soils with phosphate and magnesium oxide: Synchrotron investigation

    International Nuclear Information System (INIS)

    Sanderson, Peter; Naidu, Ravi; Bolan, Nanthi; Lim, Jung Eun; Ok, Yong Sik

    2015-01-01

    Highlights: • Quantitative speciation of Pb by XAS as a result of Phosphate and MgO treatment revealed Pb converted to pyromorphite was limited. • Subsequent MgO addition increased pyromorphite formation. • Pb was precipitated on the surface of MgO as PbO. • Bioaccessibility of Pb decreased with P treatments, but not with MgO only. - Abstract: Three Australian shooting range soils were treated with phosphate and magnesium oxide, or a combination of both to chemically stabilize Pb. Lead speciation was determined after 1 month ageing by X-ray absorption spectroscopy combined with linear combination fitting in control and treated soils. The predominant Pb species in untreated soils were iron oxide bound Pb, humic acid bound Pb and the mineral litharge. Treatment with phosphate resulted in substantial pyromorphite formation in two of the soils (TV and PE), accounting for up to 38% of Pb species present, despite the addition of excess phosphate. In MgO treated soils only, up to 43% of Pb was associated with MgO. Litharge and Pb hydroxide also formed as a result of MgO addition in the soils. Application of MgO after P treatment increased hydroxypyromorphite/pyromorphite formation relative to soils teated with phosphate only. X-ray diffraction and Scanning electron microscopy revealed PbO precipitate on the surface of MgO. Soil pH, (5.3–9.3) was an important parameter, as was the solubility of existing Pb species. The use of direct means of determination of the stabilisation of metals such as by X-ray absorption spectroscopy is desirable, particularly in relation to understanding long term stability of the immobilised contaminants.

  14. Chemical stabilisation of lead in shooting range soils with phosphate and magnesium oxide: Synchrotron investigation

    Energy Technology Data Exchange (ETDEWEB)

    Sanderson, Peter [Centre for Environmental Risk Assessment and Remediation and CRC for Contamination Assessment and Remediation of the Environment (CRC CARE), University of South Australia, University Parade, 5095 Mawson Lakes (Australia); Naidu, Ravi, E-mail: ravi.naidu@crccare.com [Centre for Environmental Risk Assessment and Remediation and CRC for Contamination Assessment and Remediation of the Environment (CRC CARE), University of South Australia, University Parade, 5095 Mawson Lakes (Australia); Bolan, Nanthi [Centre for Environmental Risk Assessment and Remediation and CRC for Contamination Assessment and Remediation of the Environment (CRC CARE), University of South Australia, University Parade, 5095 Mawson Lakes (Australia); Lim, Jung Eun; Ok, Yong Sik [Korea Biochar Research Center & Department of Biological Environment, Kangwon National University, Chuncheon 200-701 (Korea, Republic of)

    2015-12-15

    Highlights: • Quantitative speciation of Pb by XAS as a result of Phosphate and MgO treatment revealed Pb converted to pyromorphite was limited. • Subsequent MgO addition increased pyromorphite formation. • Pb was precipitated on the surface of MgO as PbO. • Bioaccessibility of Pb decreased with P treatments, but not with MgO only. - Abstract: Three Australian shooting range soils were treated with phosphate and magnesium oxide, or a combination of both to chemically stabilize Pb. Lead speciation was determined after 1 month ageing by X-ray absorption spectroscopy combined with linear combination fitting in control and treated soils. The predominant Pb species in untreated soils were iron oxide bound Pb, humic acid bound Pb and the mineral litharge. Treatment with phosphate resulted in substantial pyromorphite formation in two of the soils (TV and PE), accounting for up to 38% of Pb species present, despite the addition of excess phosphate. In MgO treated soils only, up to 43% of Pb was associated with MgO. Litharge and Pb hydroxide also formed as a result of MgO addition in the soils. Application of MgO after P treatment increased hydroxypyromorphite/pyromorphite formation relative to soils teated with phosphate only. X-ray diffraction and Scanning electron microscopy revealed PbO precipitate on the surface of MgO. Soil pH, (5.3–9.3) was an important parameter, as was the solubility of existing Pb species. The use of direct means of determination of the stabilisation of metals such as by X-ray absorption spectroscopy is desirable, particularly in relation to understanding long term stability of the immobilised contaminants.

  15. Integrating soils and geomorphology in mountains - An example from the Front Range of Colorado

    Science.gov (United States)

    Birkeland, P.W.; Shroba, R.R.; Burns, S.F.; Price, A.B.; Tonkin, P.J.

    2003-01-01

    Soil distribution in high mountains reflects the impact of several soil-forming factors. Soil geomorphologists use key pedological properties to estimate ages of Quaternary deposits of various depositional environments, estimate long-term stability and instability of landscapes, and make inferences on past climatic change. Once the influence of the soil-forming factors is known, soils can be used to help interpret some aspects of landscape evolution that otherwise might go undetected. The Front Range of Colorado rises from the plains of the Colorado Piedmont at about 1700 m past a widespread, dissected Tertiary erosion surface between 2300 and 2800 m up to an alpine Continental Divide at 3600 to over 4000 m. Pleistocene valley glaciers reached the western edge of the erosion surface. Parent rocks are broadly uniform (granitic and gneissic). Climate varies from 46 cm mean annual precipitation (MAP) and 11 ??C mean annual temperature (MAT) in the plains to 102 cm and -4 ??C, respectively, near the range crest. Vegetation follows climate with grassland in the plains, forest in the mountains, and tundra above 3450 m. Soils reflect the bioclimatic transect from plains to divide: A/Bw or Bt/Bk or K (grassland) to A/E/Bw or Bt/C (forest) to A/Bw/C (tundra). Corresponding soil pH values decrease from 8 to less than 5 with increasing elevation. The pedogenic clay minerals dominant in each major vegetation zone are: smectite (grassland), vermiculite (forest), and 1.0-1.8 nm mixed-layer clays (tundra). Within the lower forested zone, the topographic factor (aspect) results in more leached, colder soils, with relatively thin O horizons, well-expressed E horizons and Bt horizons (Alfisols) on N-facing slopes, whereas soils with thicker A horizons, less developed or no E horizons, and Bw or Bt horizons (Mollisols) are more common on S-facing slopes. The topographic factor in the tundra results in soil patterns as a consequence of wind-redistributed snow and the amount of time it

  16. A simplified Excel® algorithm for estimating the least limiting water range of soils

    Directory of Open Access Journals (Sweden)

    Leão Tairone Paiva

    2004-01-01

    Full Text Available The least limiting water range (LLWR of soils has been employed as a methodological approach for evaluation of soil physical quality in different agricultural systems, including forestry, grasslands and major crops. However, the absence of a simplified methodology for the quantification of LLWR has hampered the popularization of its use among researchers and soil managers. Taking this into account this work has the objective of proposing and describing a simplified algorithm developed in Excel® software for quantification of the LLWR, including the calculation of the critical bulk density, at which the LLWR becomes zero. Despite the simplicity of the procedures and numerical techniques of optimization used, the nonlinear regression produced reliable results when compared to those found in the literature.

  17. The effect of short-range spatial variability on soil sampling uncertainty

    Energy Technology Data Exchange (ETDEWEB)

    Perk, Marcel van der [Department of Physical Geography, Utrecht University, P.O. Box 80115, 3508 TC Utrecht (Netherlands)], E-mail: m.vanderperk@geo.uu.nl; De Zorzi, Paolo; Barbizzi, Sabrina; Belli, Maria [Agenzia per la Protezione dell' Ambiente e per i Servizi Tecnici (APAT), Servizio Laboratori, Misure ed Attivita di Campo, Via di Castel Romano, 100-00128 Roma (Italy); Fajgelj, Ales; Sansone, Umberto [International Atomic Energy Agency (IAEA), Agency' s Laboratories Seibersdorf, A-1400 Vienna (Austria); Jeran, Zvonka; Jacimovic, Radojko [Jozef Stefan Institute, Jamova 39, 1000 Ljubljana (Slovenia)

    2008-11-15

    This paper aims to quantify the soil sampling uncertainty arising from the short-range spatial variability of elemental concentrations in the topsoils of agricultural, semi-natural, and contaminated environments. For the agricultural site, the relative standard sampling uncertainty ranges between 1% and 5.5%. For the semi-natural area, the sampling uncertainties are 2-4 times larger than in the agricultural area. The contaminated site exhibited significant short-range spatial variability in elemental composition, which resulted in sampling uncertainties of 20-30%.

  18. The effect of short-range spatial variability on soil sampling uncertainty.

    Science.gov (United States)

    Van der Perk, Marcel; de Zorzi, Paolo; Barbizzi, Sabrina; Belli, Maria; Fajgelj, Ales; Sansone, Umberto; Jeran, Zvonka; Jaćimović, Radojko

    2008-11-01

    This paper aims to quantify the soil sampling uncertainty arising from the short-range spatial variability of elemental concentrations in the topsoils of agricultural, semi-natural, and contaminated environments. For the agricultural site, the relative standard sampling uncertainty ranges between 1% and 5.5%. For the semi-natural area, the sampling uncertainties are 2-4 times larger than in the agricultural area. The contaminated site exhibited significant short-range spatial variability in elemental composition, which resulted in sampling uncertainties of 20-30%.

  19. Effects of Microbial and Phosphate Amendments on the Bioavailability of Lead (Pb) in Shooting Range Soil

    Energy Technology Data Exchange (ETDEWEB)

    Brigmon, Robin; Wilson, Christina; Knox, Anna; Seaman, John; Smith, Garriet

    2005-06-16

    Heavy metals including lead (Pb) are released continually into the environment as a result of industrial, recreational, and military activities. Lead ranked number two on the CERCLA Priority List of Hazardous Substances and was identified as a major hazardous chemical found on 47% of USEPA's National Priorities List sites (Hettiarachchi and Pierzynski 2004). In-situ remediation of lead (Pb) contaminated soils may be accomplished by changing the soil chemistry and structure with the application of microbial and phosphate amendments. Soil contaminated with lead bullets was collected from the surface of the berm at Savannah River Site (SRS) Small Arms Training Academy (SATA) in Aiken, SC. While uncontaminated soils typically have Pb levels ranging from 2 to 200 mg/kg (Berti et al. 1998), previous analysis show Pb levels of the SATA berm to reach 8,673 mg/kg. Biosurfactants are surface-active compounds naturally produced by soil bacteria that can bind metals. Biosurfactants have a wide variety of chemical structures that reduce interfacial surface tensions (Jennings and Tanner 2000) and have demonstrated efficient metal complexion (Lin 1996). Biosurfactants also have the potential to change the availability of natural organic matter (Strong-Gunderson 1995). Two types of bacteria, Alcaligenes piechaudii and Pseudomonas putida, were employed as amendments based on their ability to produce biosurfactants and survive in metal-contaminated soils. Apatites (calcium phosphate compounds) are important in the formation of Pb phosphates. Pb phosphates form rapidly when phosphate is available and are the most stable environmental form of lead in soil (Ruby et al.1998). Pyromorphites in particular remain insoluble under a wide range of environmental conditions (Zhang et al. 1998). The three apatites evaluated in the current study were North Carolina apatite (NCA), Florida apatite (FA), and biological apatite (BA). BA is ground fish bone that has few impurities such as As, Cr

  20. Extreme soil acidity from biodegradable trap and skeet targets increases severity of pollution at shooting ranges.

    Science.gov (United States)

    McTee, Michael R; Mummey, Daniel L; Ramsey, Philip W; Hinman, Nancy W

    2016-01-01

    Lead pollution at shooting ranges overshadows the potential for contamination issues from trap and skeet targets. We studied the environmental influence of targets sold as biodegradable by determining the components of the targets and sampling soils at a former sporting clay range. Targets comprised approximately 53% CaCO3, 41% S(0), and 6% modifiers, and on a molar basis, there was 2.3 times more S(0) than CaCO3. We observed a positive correlation between target cover and SO4(2-) (ρ=0.82, Psoil pH (ρ=0.62, P=0.006). For sites that had pH values below 3, 24tons of lime per 1000tons of soil would be required to raise soil pH to 6.5. Lime-facilitated pH increases would be transitory because S(0) would continue to oxidize to H2SO4 until the S(0) is depleted. This study demonstrates that biodegradable trap and skeet targets can acidify soil, which has implications for increasing the mobility of Pb from shotgun pellets. Copyright © 2015 Elsevier B.V. All rights reserved.

  1. Conceptual Model for the Transport of Energetic Residues from Surface Soil to Groundwater by Range Activities

    Science.gov (United States)

    2006-11-01

    fluoranthenes are common products of diesel emissions (Hering et al. 1984). Benzo(a)pyrene is common in creosote and motor vehicle particulate emissions (Wild...military ranges are associated with on-site vegetative burning, diesel exhaust, and atmospheric deposi- tion. Metals Metal oxides and salts are...Hence, slow transport of TNT from the soil bed is a limiting fac- tor in the phytoremediation or bioremediation of TNT. Fluxes were, in de- creasing

  2. Effects of soil dilution and amendments (mussel shell, cow bone, and biochar) on Pb availability and phytotoxicity in military shooting range soil.

    Science.gov (United States)

    Ahmad, Mahtab; Soo Lee, Sang; Yang, Jae E; Ro, Hee-Myong; Han Lee, Young; Sik Ok, Yong

    2012-05-01

    Bioavailability and bioaccessibility determine the level of metal toxicity in the soils. Inorganic soil amendments may decrease metal bioavailability and enhance soil quality. This study used mussel shell, cow bone, and biochar to reduce lead (Pb) toxicity in the highly contaminated military shooting range soil in Korea. Water-soluble and 1-M ammonium nitrate extractions, and a modified physiologically based extraction test (PBET) were performed to determine Pb bioavailability and bioaccessibility in the soil, respectively. Active C in the soil was also measured to evaluate the effects of the amendments on biological soil quality. The Pb contaminated soil was diluted in serial with uncontaminated soil for the bioassays. Seed germination and root elongation tests using lettuce (Lactuca sativa) showed increases in germination percentage and root length in soil treated with the amendments. Biochar was most effective and increased seed germination by 360% and root length by 189% compared to the unamended soil. Up to 20% soil dilution resulted in more than 50% seed germination. Bioavailability and bioaccessibility of Pb in the soils were decreased by 92.5% and 48.5% with mussel shell, by 84.8% and 34.5% with cow bone, and by 75.8% and 12.5% with biochar, respectively, compared to the unamended soil. We found that the Pb availability in the military shooting range soil can be reduced effectively by the tested amendments or soil dilution alternately, thereby decreasing the risk of ecotoxicity. Furthermore, the increasing active C from the amendments revitalized the soil contaminated with Pb. Copyright © 2012 Elsevier Inc. All rights reserved.

  3. Can the soil fauna of boreal forests recover from lead-derived stress in a shooting range area?

    Science.gov (United States)

    Selonen, Salla; Liiri, Mira; Setälä, Heikki

    2014-04-01

    The responses of soil faunal communities to lead (Pb) contamination in a shooting range area and the recovery of these fauna after range abandonment were studied by comparing the communities at an active shotgun shooting range, an abandoned shooting range, and a control site, locating in the same forest. Despite the similar overall Pb pellet load at the shooting ranges, reaching up to 4 kg m(-2), Pb concentrations in the top soil of the abandoned range has decreased due to the accumulation of detritus on the soil surface. As a consequence, soil animal communities were shown to recover from Pb-related disturbances by utilizing the less contaminated soil layer. Microarthropods showed the clearest signs of recovery, their numbers and community composition being close to those detected at the control site. However, in the deepest organic soil layer, the negative effects of Pb were more pronounced at the abandoned than at the active shooting range, which was detected as altered microarthropod and nematode community structures, reduced abundances of several microarthropod taxa, and the total absence of enchytraeid worms. Thus, although the accumulation of fresh litter on soil surface can promote the recovery of decomposer communities in the top soil, the gradual release of Pb from corroding pellets may pose a long-lasting risk for decomposer taxa deeper in the soil.

  4. Phosphate application to firing range soils for Pb immobilization: The unclear role of phosphate

    International Nuclear Information System (INIS)

    Chrysochoou, Maria; Dermatas, Dimitris; Grubb, Dennis G.

    2007-01-01

    Phosphate treatment has emerged as a widely accepted approach to immobilize Pb in contaminated soils and waste media, relying on the formation of the highly insoluble mineral pyromorphite as solubility-controlling phase for Pb. As such, phosphate treatment has been proposed as a Best Management Practice (BMP) for firing ranges where Pb occurs in its metallic forms and several other phases (carbonates, oxides). While pyromorphite thermodynamically has the potential to control Pb solubility at low levels, its formation is kinetically controlled by pH, the solubility of the phosphate source, and the solubility of Pb species. Treatability studies have shown that excess quantities of soluble and acidic phosphate sources, such as phosphoric acid, are necessary for successful in situ treatment. Even under these conditions, Extended X-ray Absorption Fine Structure (EXAFS), the only reliable method to identify and quantify Pb speciation, showed that Pb conversion to pyromorphite in in situ treated soils was less than 45% after 32 months. Furthermore, the use of lime (CaO) to restore soil pH in acidified soil treatments inhibited further conversion. Additionally, phosphate treatment is known to reduce bioavailability through pyromorphite formation in the intestinal tract, and the phytoaccumulation of Pb; both desirable effects for Pb-impacted areas. Given the costs of phosphate treatment, the use of biogenic phosphate sources, such as bone meal, may be a more environmentally sustainable approach toward this end. In the many studies focusing on phosphate treatment, the attendant P leaching and eutrophication have been largely overlooked, along with other issues such as the enhanced leaching of oxyanionic contaminants, such as Se, As and W. The success and sustainability of applying phosphate as a BMP in firing range soils therefore remain questionable

  5. Screening variability and change of soil moisture under wide-ranging climate conditions: Snow dynamics effects.

    Science.gov (United States)

    Verrot, Lucile; Destouni, Georgia

    2015-01-01

    Soil moisture influences and is influenced by water, climate, and ecosystem conditions, affecting associated ecosystem services in the landscape. This paper couples snow storage-melting dynamics with an analytical modeling approach to screening basin-scale, long-term soil moisture variability and change in a changing climate. This coupling enables assessment of both spatial differences and temporal changes across a wide range of hydro-climatic conditions. Model application is exemplified for two major Swedish hydrological basins, Norrström and Piteälven. These are located along a steep temperature gradient and have experienced different hydro-climatic changes over the time period of study, 1950-2009. Spatially, average intra-annual variability of soil moisture differs considerably between the basins due to their temperature-related differences in snow dynamics. With regard to temporal change, the long-term average state and intra-annual variability of soil moisture have not changed much, while inter-annual variability has changed considerably in response to hydro-climatic changes experienced so far in each basin.

  6. Source apportionment of soil heavy metals using robust absolute principal component scores-robust geographically weighted regression (RAPCS-RGWR) receptor model.

    Science.gov (United States)

    Qu, Mingkai; Wang, Yan; Huang, Biao; Zhao, Yongcun

    2018-06-01

    The traditional source apportionment models, such as absolute principal component scores-multiple linear regression (APCS-MLR), are usually susceptible to outliers, which may be widely present in the regional geochemical dataset. Furthermore, the models are merely built on variable space instead of geographical space and thus cannot effectively capture the local spatial characteristics of each source contributions. To overcome the limitations, a new receptor model, robust absolute principal component scores-robust geographically weighted regression (RAPCS-RGWR), was proposed based on the traditional APCS-MLR model. Then, the new method was applied to the source apportionment of soil metal elements in a region of Wuhan City, China as a case study. Evaluations revealed that: (i) RAPCS-RGWR model had better performance than APCS-MLR model in the identification of the major sources of soil metal elements, and (ii) source contributions estimated by RAPCS-RGWR model were more close to the true soil metal concentrations than that estimated by APCS-MLR model. It is shown that the proposed RAPCS-RGWR model is a more effective source apportionment method than APCS-MLR (i.e., non-robust and global model) in dealing with the regional geochemical dataset. Copyright © 2018 Elsevier B.V. All rights reserved.

  7. Chemical Speciation and Quantitative Evaluation of Heavy Metal Pollution Hazards in Two Army Shooting Range Backstop Soils.

    Science.gov (United States)

    Islam, Mohammad Nazrul; Nguyen, Xuan Phuc; Jung, Ho-Young; Park, Jeong-Hun

    2016-02-01

    The chemical speciation and ecological risk assessment of heavy metals in two shooting range backstop soils in Korea were studied. Both soils were highly contaminated with Cd, Cu, Pb, and Sb. The chemical speciation of heavy metals reflected the present status of contamination, which could help in promoting management practices. We-rye soil had a higher proportion of exchangeable and carbonate bound metals and water-extractable Cd and Sb than the Cho-do soil. Bioavailable Pb represented 42 % of the total Pb content in both soils. A significant amount of Sb was found in the two most bioavailable fractions, amounting to ~32 % in the soil samples, in good agreement with the batch leaching test using water. Based on the values of ecological risk indices, both soils showed extremely high potential risk and may represent serious environmental problems.

  8. A compendium of results from long-range alpha detector soil surface monitoring: June 1992--May 1994

    International Nuclear Information System (INIS)

    Garner, S.E.; Bounds, J.A.; Allander, K.S.; Johnson, J.D.; MacArthur, D.W.; Caress, R.W.

    1994-11-01

    Soil surface monitors based on long-range alpha detector (LRAD) technology are being used to monitor alpha contamination at various sites in the Department of Energy complex. These monitors, the large soil-surface monitor (LSSM) and the small soil-surface monitor (SSSM), were used to help characterize sites at Fernald, Ohio, and active or inactive firing sites at Sandia National Laboratories and Los Alamos National Laboratory. Monitoring results are presented herein in chronological order

  9. Immobilization of lead in a Korean military shooting range soil using eggshell waste: an integrated mechanistic approach.

    Science.gov (United States)

    Ahmad, Mahtab; Hashimoto, Yohey; Moon, Deok Hyun; Lee, Sang Soo; Ok, Yong Sik

    2012-03-30

    This study evaluated the effectiveness of eggshell and calcined eggshell on lead (Pb) immobilization in a shooting range soil. Destructive and non-destructive analytical techniques were employed to determine the mechanism of Pb immobilization. The 5% additions of eggshell and calcined eggshell significantly decreased the TCLP-Pb concentration by 68.8% due mainly to increasing soil pH. Eggshell and calcined-eggshell amendments decreased the exchangeable Pb fraction to ≈ 1% of the total Pb in the soil, while the carbonate-associated Pb fraction was increased to 40.0-47.1% at >15% application rates. The thermodynamic modeling on Pb speciation in the soil solution predicted the precipitation of Pb-hydroxide [Pb(OH)(2)] in soils amended with eggshell and calcined eggshell. The SEM-EDS, XAFS and elemental dot mapping revealed that Pb in soil amended with calcined eggshell was associated with Si and Ca, and may be immobilized by entrapping into calcium-silicate-hydrate. Comparatively, in the soil amended with eggshell, Pb was immobilized via formation of Pb-hydroxide or lanarkite [Pb(2)O(SO(4))]. Applications of amendments increased activities of alkaline phosphatase up to 3.7 times greater than in the control soil. The use of eggshell amendments may have potential as an integrated remediation strategy that enables Pb immobilization and soil biological restoration in shooting range soils. Copyright © 2012 Elsevier B.V. All rights reserved.

  10. Soil conditions and land use intensification effects on soil microbial communities across a range of European field sites

    NARCIS (Netherlands)

    Thomson, Bruce C.; Tisserant, Emilie; Plassart, Pierre; Uroz, Stéphane; Griffiths, Rob I.; Hannula, S. Emilia; Buée, Marc; Mougel, Christophe; Ranjard, Lionel; Van Veen, Johannes A.; Martin, Francis; Bailey, Mark J.; Lemanceau, Philippe

    2015-01-01

    Abstract Intensive land use practices necessary for providing food and raw materials are known to have a deleterious effect on soil. However, the effects such practices have on soil microbes are less well understood. To investigate the effects of land use intensification on soil microbial

  11. Assessment of soil-gas, seep, and soil contamination at the North Range Road Landfill, Fort Gordon, Georgia, 2008-2009

    Science.gov (United States)

    Landmeyer, James E.; Falls, W. Fred; Ratliff, W. Hagan; Wellborn, John B.

    2011-01-01

    Soil gas, seeps, and soil were assessed for contaminants at the North Range Road Landfill at Fort Gordon, Georgia, from October 2008 to September 2009. The assessment included delineating organic contaminants present in soil-gas samples beneath the area estimated to be the landfill and in water samples collected from three seeps at the base of the landfill. Inorganic contaminants were determined in three seep samples and in soil samples. This assessment was conducted to provide environmental contamination data to Fort Gordon pursuant to requirements for the Resource Conservation and Recovery Act Part B Hazardous Waste Permit process.

  12. Long-range alpha detection applied to soil contamination and waste monitoring

    International Nuclear Information System (INIS)

    MacArthur, D.W.; Allander, K.S.; Bounds, J.A.; Close, D.A.; McAtee, J.L.

    1992-01-01

    Alpha contamination monitoring has been traditionally limited by the short range of alpha particles in air and through detector windows. The long-range alpha detector (LRAD) described in this paper circumvents that limitation by detecting alpha-produced ions, rather than alpha particles directly. Since the LRAD is sensitive to all ions, it can monitor all contamination present on a large surface at one time. Because air is the ''detector gas,'' the LRAD can detect contamination on any surface to which air can penetrate. We present data showing the sensitivity of LRAD detectors, as well as documenting their ability to detect alpha sources in previously unmonitorable locations, and verifying the ion lifetime. Specific designs and results for soil contamination and waste monitors are also included

  13. Stabilization of lead and copper contaminated firing range soil using calcined oyster shells and fly ash.

    Science.gov (United States)

    Moon, Deok Hyun; Park, Jae-Woo; Cheong, Kyung Hoon; Hyun, Seunghun; Koutsospyros, Agamemnon; Park, Jeong-Hun; Ok, Yong Sik

    2013-12-01

    A stabilization/solidification treatment scheme was devised to stabilize Pb and Cu contaminated soil from a firing range using renewable waste resources as additives, namely waste oyster shells (WOS) and fly ash (FA). The WOS, serving as the primary stabilizing agent, was pre-treated at a high temperature to activate quicklime from calcite. Class C FA was used as a secondary additive along with the calcined oyster shells (COS). The effectiveness of the treatment was evaluated by means of the toxicity characteristic leaching procedure (TCLP) and the 0.1 M HCl extraction tests following a curing period of 28 days. The combined treatment with 10 wt% COS and 5 wt% FA cause a significant reduction in Pb (>98 %) and Cu (>96 %) leachability which was indicated by the results from both extraction tests (TCLP and 0.1 M HCl). Scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDX) analyses are used to investigate the mechanism responsible for Pb and Cu stabilization. SEM-EDX results indicate that effective Pb and Cu immobilization using the combined COS-FA treatment is most probably associated with ettringite and pozzolanic reaction products. The treatment results suggest that the combined COS-FA treatment is a cost effective method for the stabilization of firing range soil.

  14. Immobilization of lead in a Korean military shooting range soil using eggshell waste: An integrated mechanistic approach

    Energy Technology Data Exchange (ETDEWEB)

    Ahmad, Mahtab [Department of Biological Environment, Kangwon National University, Chuncheon 200-701 (Korea, Republic of); Hashimoto, Yohey [Department of Bioresource Science, Mie University, 1577 Kurima-machiya, Mie 514-8507 (Japan); Moon, Deok Hyun [Department of Environmental Engineering, Chosun University, Gwangju 501-759 (Korea, Republic of); Lee, Sang Soo, E-mail: sslee97@kangwon.ac.kr [Department of Biological Environment, Kangwon National University, Chuncheon 200-701 (Korea, Republic of); Ok, Yong Sik, E-mail: soilok@kangwon.ac.kr [Department of Biological Environment, Kangwon National University, Chuncheon 200-701 (Korea, Republic of)

    2012-03-30

    Highlights: Black-Right-Pointing-Pointer Eggshell and calcined eggshell immobilized Pb in the shooting range soil. Black-Right-Pointing-Pointer Calcined eggshell was more effective on Pb immobilization compared to eggshell. Black-Right-Pointing-Pointer Exchangeable Pb fractions were transformed to carbonate bound fractions. Black-Right-Pointing-Pointer Calcined eggshell stabilized Pb by enwrapping into calcium silicate hydrate. Black-Right-Pointing-Pointer Soil Pb toxicity can be reduced by applying eggshell and calcined eggshell. - Abstract: This study evaluated the effectiveness of eggshell and calcined eggshell on lead (Pb) immobilization in a shooting range soil. Destructive and non-destructive analytical techniques were employed to determine the mechanism of Pb immobilization. The 5% additions of eggshell and calcined eggshell significantly decreased the TCLP-Pb concentration by 68.8% due mainly to increasing soil pH. Eggshell and calcined-eggshell amendments decreased the exchangeable Pb fraction to {approx}1% of the total Pb in the soil, while the carbonate-associated Pb fraction was increased to 40.0-47.1% at >15% application rates. The thermodynamic modeling on Pb speciation in the soil solution predicted the precipitation of Pb-hydroxide [Pb(OH){sub 2}] in soils amended with eggshell and calcined eggshell. The SEM-EDS, XAFS and elemental dot mapping revealed that Pb in soil amended with calcined eggshell was associated with Si and Ca, and may be immobilized by entrapping into calcium-silicate-hydrate. Comparatively, in the soil amended with eggshell, Pb was immobilized via formation of Pb-hydroxide or lanarkite [Pb{sub 2}O(SO{sub 4})]. Applications of amendments increased activities of alkaline phosphatase up to 3.7 times greater than in the control soil. The use of eggshell amendments may have potential as an integrated remediation strategy that enables Pb immobilization and soil biological restoration in shooting range soils.

  15. Immobilization of lead in a Korean military shooting range soil using eggshell waste: An integrated mechanistic approach

    International Nuclear Information System (INIS)

    Ahmad, Mahtab; Hashimoto, Yohey; Moon, Deok Hyun; Lee, Sang Soo; Ok, Yong Sik

    2012-01-01

    Highlights: ► Eggshell and calcined eggshell immobilized Pb in the shooting range soil. ► Calcined eggshell was more effective on Pb immobilization compared to eggshell. ► Exchangeable Pb fractions were transformed to carbonate bound fractions. ► Calcined eggshell stabilized Pb by enwrapping into calcium silicate hydrate. ► Soil Pb toxicity can be reduced by applying eggshell and calcined eggshell. - Abstract: This study evaluated the effectiveness of eggshell and calcined eggshell on lead (Pb) immobilization in a shooting range soil. Destructive and non-destructive analytical techniques were employed to determine the mechanism of Pb immobilization. The 5% additions of eggshell and calcined eggshell significantly decreased the TCLP-Pb concentration by 68.8% due mainly to increasing soil pH. Eggshell and calcined-eggshell amendments decreased the exchangeable Pb fraction to ∼1% of the total Pb in the soil, while the carbonate-associated Pb fraction was increased to 40.0–47.1% at >15% application rates. The thermodynamic modeling on Pb speciation in the soil solution predicted the precipitation of Pb-hydroxide [Pb(OH) 2 ] in soils amended with eggshell and calcined eggshell. The SEM-EDS, XAFS and elemental dot mapping revealed that Pb in soil amended with calcined eggshell was associated with Si and Ca, and may be immobilized by entrapping into calcium-silicate-hydrate. Comparatively, in the soil amended with eggshell, Pb was immobilized via formation of Pb-hydroxide or lanarkite [Pb 2 O(SO 4 )]. Applications of amendments increased activities of alkaline phosphatase up to 3.7 times greater than in the control soil. The use of eggshell amendments may have potential as an integrated remediation strategy that enables Pb immobilization and soil biological restoration in shooting range soils.

  16. The effect of environmental conditions and soil physicochemistry on phosphate stabilisation of Pb in shooting range soils.

    Science.gov (United States)

    Sanderson, Peter; Naidu, Ravi; Bolan, Nanthi

    2016-04-01

    The stabilisation of Pb in the soil by phosphate is influenced by environmental conditions and physicochemical properties of the soils to which it is applied. Stabilisation of Pb by phosphate was examined in four soils under different environmental conditions. The effect of soil moisture and temperature on stabilisation of Pb by phosphate was examined by measurement of water extractable and bioaccessible Pb, sequential fractionation and X-ray absorption spectroscopy. The addition of humic acid, ammonium nitrate and chloride was also examined for inhibition or improvement of Pb stability with phosphate treatment. The effect of moisture level varied between soils. In soil MB and DA a soil moisture level of 50% water holding capacity was sufficient to maximise stabilisation of Pb, but in soil TV and PE reduction in bioaccessible Pb was inhibited at this moisture level. Providing moisture at twice the soil water holding capacity did not enhance the effect of phosphate on Pb stabilisation. The difference of Pb stability as a result of incubating phosphate treated soils at 18 °C and 37 °C was relatively small. However wet-dry cycles decreased the effectiveness of phosphate treatment. The reduction in bioaccessible Pb obtained was between 20 and 40% with the most optimal treatment conditions. The reduction in water extractable Pb by phosphate was substantial regardless of incubation conditions and the effect of different temperature and soil moisture regimes was not significant. Selective sequential extraction showed phosphate treatment converted Pb in fraction 1 (exchangeable, acid and water soluble) to fraction 2 (reducible). There were small difference in fraction 4 (residual) Pb and fraction 1 as a result of treatment conditions. X-ray absorption spectroscopy of stabilised PE soil revealed small differences in Pb speciation under varying soil moisture and temperature treatments. The addition of humic acid and chloride produced the greatest effect on Pb speciation in

  17. Identification of factors most important for ammonia emission from fertilized soils for potato production using principal component analysis

    Science.gov (United States)

    Guodoong Liu; Yuncong Li; Kati W. Migliaccio; Ying Ouyang; Ashok K. Alva

    2011-01-01

    Ammonia (NH3) emissions from fertilized soils are a costly problem that is undermining agricultural and ecological sustainability worldwide. Ammonia emissions from crop production have been reliably documented in recent years. However, insufficient efforts have been made to determine the factors most influential in facilitating NH3 emissions. The goal of this study was...

  18. 3-Way characterization of soils by Procrustes rotation, matrix-augmented principal components analysis and parallel factor analysis

    Czech Academy of Sciences Publication Activity Database

    Andrade, J.M.; Kubista, Mikael; Carlosena, A.; Prada, D.

    2007-01-01

    Roč. 603, č. 1 (2007), s. 20-29 ISSN 0003-2670 Institutional research plan: CEZ:AV0Z50520514 Keywords : PCA * heavy metals * soil Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 3.186, year: 2007

  19. Assessment of Selected Heavy Metals and Enzymes in Soil Within the Range of Impact of Illegal Dumping Sites

    International Nuclear Information System (INIS)

    Bartkowiak, A.; Lemanowicz, J.; Siwik-Ziomek, A.

    2016-01-01

    Defining the physicochemical and biological parameters in soil under illegally dumping sites provides information on the real threat and the direction of changes in the soil environment. The paper demonstrates the result of changes in the properties in soil as a result of the operation of illegal dumping sites. Soil was sampled from the research points located on the outskirts of the city of Bydgoszcz (Poland) from the site not affected by illegal dumping sites (control C), within the dumping sites, having removed the waste layer (W), and 10 m away from the dumping sites (W 10). In the soil the content of phosphorus, potassium, magnesium and sulphur, total content of copper, zinc, lead and nickel as well as the activity of enzymes were assayed. The content of Pb, Zn, Cu and Ni in the soil samples qualifies the soils as representing the soil category with natural content. The greatest activity of all the enzymes analysed was identified in the soil sampled from the control point affected by waste, whereas the highest content of macroelements was reported in the soil from the dumping sites (W 10). A high variation in the enzymes under study in soils confirms a high value of the coefficient of variation (CV >36%). The analysis of correlation confirmed the relationship between the content of organic carbon compounds and the content of zinc, lead, nickel. The soils show a slight value of the coefficient of contamination for heavy metals (CF<1). The contamination degree (Cdeg) ranged from 1.993 to 5.116, which points to a low level of soil contamination with Zn, Cu, Pb and Ni.

  20. Carbon dioxide efflux from a 550 m3 soil across a range of soul temperatues

    Science.gov (United States)

    Ramesh Murthy; Kevin L. Griffin; Stanley J. Zarnoch; Philip M. Dougherty; Barbara Watson; Joost Van Haren; Randy L. Patterson; Tilka Mahato

    2003-01-01

    Because of scaling problems point measurements of soil CO2 efflux on a small volume of soil may not necessarily reflect an overall community response. The aim of this study was to test this hypothesis in the Biosphere 2 facility and achieve the following broad goals: (1) investigate soil net CO2 exchange–temperature...

  1. A Range-Wide Experiment to Investigate Nutrient and Soil Moisture Interactions in Loblolly Pine Plantations

    Directory of Open Access Journals (Sweden)

    Rodney E. Will

    2015-06-01

    Full Text Available The future climate of the southeastern USA is predicted to be warmer, drier and more variable in rainfall, which may increase drought frequency and intensity. Loblolly pine (Pinus taeda is the most important commercial tree species in the world and is planted on ~11 million ha within its native range in the southeastern USA. A regional study was installed to evaluate effects of decreased rainfall and nutrient additions on loblolly pine plantation productivity and physiology. Four locations were established to capture the range-wide variability of soil and climate. Treatments were initiated in 2012 and consisted of a factorial combination of throughfall reduction (approximate 30% reduction and fertilization (complete suite of nutrients. Tree and stand growth were measured at each site. Results after two growing seasons indicate a positive but variable response of fertilization on stand volume increment at all four sites and a negative effect of throughfall reduction at two sites. Data will be used to produce robust process model parameterizations useful for simulating loblolly pine growth and function under future, novel climate and management scenarios. The resulting improved models will provide support for developing management strategies to increase pine plantation productivity and carbon sequestration under a changing climate.

  2. Radiometric characterization of six soils in the microwave X-range through complex permittivity measurements

    International Nuclear Information System (INIS)

    Palme, U.W.

    1987-10-01

    Estimating and monitoring up-to-date soil moisture conditions over extensive areas through passive (or active) microwave remote sensing techniques requires the knowledge of the complex relative permittivity (ε r * ) in function of soil moisture. X-band measurements of ε r * for different moisture conditions were made in laboratory for soil samples of six important Soils (PV 2 , LV 3 , LR d , LE 1 , SAP and Sc). Using a theoretical model and computational programmes developed, these measurements allowed estimates of the emissive characteristics of the soils that would be expected with the X-Band Microwave Radiometer built at INPE. The results, new, for soils from tropical regions, showed that only the physical characteristics and properties of the soils are not sufficient to explain the behaviour of ε r * in function of soil moisture, indicating that the chemical and/or mineralogical properties of the soils do have an important contribution. The results also showed thast ε r * in function of soil moisture depends on soil class. (author) [pt

  3. Soil charcoal from the plains to tundra in the Colorado Front Range

    Science.gov (United States)

    Sanford, R. L.; Licata, C.

    2010-12-01

    Throughout the forests of the central Rockies, soil charcoal from Holocene wildfires has been produced in response to wildland natural fire regimes. The extent and spatial distribution of soil charcoal production is poorly documented in this region, especially with regard to forests and shrublands at different elevations. Soil charcoal is a super-passive C pool derived from woody biomass that can be sequestered for millennia in forest soils. Recent research indicates that soil charcoal may promote enhanced soil fertility. Additionally, soil charcoal is an often overlooked component of soil C mass and flux. We hypothesize that differences in forest and shrubland fire regimes over the millennia have resulted in different soil charcoal amounts. Geospatial data were used to locate random sample plots in foothills shrublands (Cercocarpus montanus), and four forest types; ponderosa pine (Pinus ponderosa), Douglas-fir (Pseudotsuga menziesii), lodgepole pine (Pinus contorta) and spruce-fir (Picea engelmannii - Abies lasiocarpa). Sample plots were stratified to occur with the mid 200 m elevation band of each vegetation type with east aspect, and 10-30% slope. Soils were sampled widely at 0-10 cm depth and analyzed for total soil C and soil charcoal C via chemical digestion and dry combustion techniques. Overall, soil charcoal is four times more abundant in spruce-fir forests than in foothills shrublands (1.9 +/- 0.92 Mg C/ha versus 0.54 +/- 0.44 Mg C/ha). Soil charcoal is also abundant in lodgepole pine and ponderosa pine soils (1.4 +/- 1.02 Mg C/ha and 1.4 +/- 0.54 Mg C/ha respectively) but is less plentiful in Douglas-fir soils (1.0 +/- 0.67). Spruce-fir forests have the most above ground biomass, slower decomposition rates and a less frequent mean fire return interval than the other four forests, hence it makes sense that high per-fire rates of charcoal production would occur in the spruce-fir zone, given large amounts of surface fuels at the time of fire. In contrast

  4. Principal Ports

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Principal Ports are defined by port limits or US Army Corps of Engineers (USACE) projects, these exclude non-USACE projects not authorized for publication. The...

  5. Lead Determination and Heterogeneity Analysis in Soil from a Former Firing Range

    Science.gov (United States)

    Urrutia-Goyes, Ricardo; Argyraki, Ariadne; Ornelas-Soto, Nancy

    2017-07-01

    Public places can have an unknown past of pollutants deposition. The exposition to such contaminants can create environmental and health issues. The characterization of a former firing range in Athens, Greece will allow its monitoring and encourage its remediation. This study is focused on Pb contamination in the site due to its presence in ammunition. A dense sampling design with 91 location (10 m apart) was used to determine the spatial distribution of the element in the surface soil of the study area. Duplicates samples were also collected one meter apart from 8 random locations to estimate the heterogeneity of the site. Elemental concentrations were measured using a portable XRF device after simple sample homogenization in the field. Robust Analysis of Variance showed that the contributions to the total variance were 11% from sampling, 1% analytical, and 88% geochemical; reflecting the suitability of the technique. Moreover, the extended random uncertainty relative to the mean concentration was 91.5%; confirming the high heterogeneity of the site. Statistical analysis defined a very high contamination in the area yielding to suggest the need for more in-depth analysis of other contaminants and possible health risks.

  6. In situ pilot test for bioremediation of energetic compound-contaminated soil at a former military demolition range site.

    Science.gov (United States)

    Jugnia, Louis B; Manno, Dominic; Drouin, Karine; Hendry, Meghan

    2018-05-04

    Bioremediation was performed in situ at a former military range site to assess the performance of native bacteria in degrading hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) and 2,4-dinitrotoluene (2,4-DNT). The fate of these pollutants in soil and soil pore water was investigated as influenced by waste glycerol amendment to the soil. Following waste glycerol application, there was an accumulation of organic carbon that promoted microbial activity, converting organic carbon into acetate and propionate, which are intermediate compounds in anaerobic processes. This augmentation of anaerobic activity strongly correlated to a noticeable reduction in RDX concentrations in the amended soil. Changes in concentrations of RDX in pore water were similar to those observed in the soil suggesting that RDX leaching from the soil matrix, and treatment with waste glycerol, contributed to the enhanced removal of RDX from the water and soil. This was not the case with 2,4-DNT, which was neither found in pore water nor affected by the waste glycerol treatment. Results from saturated conditions and Synthetic Precipitation Leaching Procedure testing, to investigate the environmental fate of 2,4-DNT, indicated that 2,4-DNT found on site was relatively inert and was likely to remain in its current state on the site.

  7. Fractionation and distribution of risk elements in soil profiles at a Czech shooting range

    Czech Academy of Sciences Publication Activity Database

    Ash, C.; Tejnecký, V.; Šebek, O.; Němeček, K.; Žahourová-Dubová, L.; Bakardjieva, Snejana; Drahota, P.; Drábek, O.

    2013-01-01

    Roč. 59, č. 3 (2013), s. 121-129 ISSN 1214-1178 Institutional support: RVO:61388980 Keywords : lead * inorganic contaminants * BCR sequential extraction * soil probe * alkaline soil Subject RIV: CA - Inorganic Chemistry Impact factor: 1.113, year: 2013

  8. Enhanced thermal conduction -- An alternative solution for removing a broad range of hydrocarbons from contaminated soils

    Energy Technology Data Exchange (ETDEWEB)

    Bova, J.C.

    1999-07-01

    This paper presents an overview of Enhanced Thermal Conduction (ETC), an ex-situ soil remediation process. A review of a practical demonstration of this process which was conducted by Woodward-Clyde Consultants to determine the capability of the technology for remediating soils from gasworks sites that have been contaminated with petroleum hydrocarbons, polynuclear hydrocarbons (PAHs) and cyanide is also presented in this paper. Projections for using this process to treat soils contaminated with other hazardous materials such as TCE PCE and PCB's are discussed as well.

  9. Principal components

    NARCIS (Netherlands)

    Hallin, M.; Hörmann, S.; Piegorsch, W.; El Shaarawi, A.

    2012-01-01

    Principal Components are probably the best known and most widely used of all multivariate analysis techniques. The essential idea consists in performing a linear transformation of the observed k-dimensional variables in such a way that the new variables are vectors of k mutually orthogonal

  10. Plant–soil feedback in native vs. invasive populations of a range expanding plant

    Czech Academy of Sciences Publication Activity Database

    Dostálek, Tomáš; Münzbergová, Zuzana; Kladivová, A.; Macel, M.

    2016-01-01

    Roč. 399, 1-2 (2016), s. 209-220 ISSN 0032-079X Institutional support: RVO:67985939 Keywords : Rorippa australis * soil community * invasive species Subject RIV: EF - Botanics Impact factor: 3.052, year: 2016

  11. Lead and Antimony Speciation in Shooting Range Soils: Molecular Scale Analysis, Temporal Trends and Mobility

    Science.gov (United States)

    2017-11-20

    years is shown in Figure 12. The steel and Cu jacket partially separated from one another, leaving the Pb/Sb slug exposed. While Pb comprises the bulk...crust appears to act as a cement between the bullet fragments and surrounding soil particles as well as between individual soil particles. Similar...few hundred micrometers from the weathering crust (Vantelon et al., 2005). The distribution of Sb is discontinuous in the bullet alloy and cemented

  12. Structural changes in latosols of the cerrado region: I - relationships between soil physical properties and least limiting water range

    Directory of Open Access Journals (Sweden)

    Eduardo da Costa Severiano

    2011-06-01

    Full Text Available The agricultural potential of Latosols of the Brazilian Cerrado region is high, but when intensively cultivated under inappropriate management systems, the porosity can be seriously reduced, leading to rapid soil degradation. Consequently, accelerated erosion and sedimentation of springs and creeks have been observed. Therefore, the objective of this study was to evaluate structural changes of Latosols in Rio Verde, Goiás, based on the Least Limiting Water Range (LLWR, and relationships between LLWR and other physical properties. Soil samples were collected from the B horizons of five oxidic Latosols representing the textural variability of the Latosols of the Cerrado biome. LLWR and other soil physical properties were determined at various soil compaction degrees induced by uniaxial compression. Soil compaction caused effects varying from enhanced plant growth due to higher water retention, to severe restriction of edaphic functions. Also, inverse relationships were observed between clay content and bulk density values (Bd under different structural conditions. Bd values corresponding to critical soil macroporosity (BdcMAC were more restrictive to a sustainable use of the studied Latosols than the critical Bd corresponding to LLWR (BdcLLWR. The high tolerable compression potential of these oxidic Latosols was related to the high aeration porosity associated to the granular structure.

  13. Modeling Short-Range Soil Variability and its Potential Use in Variable-Rate Treatment of Experimental Plots

    Directory of Open Access Journals (Sweden)

    A Moameni

    2011-02-01

    Full Text Available Abstract In Iran, the experimental plots under fertilizer trials are managed in such a way that the whole plot area uniformly receives agricultural inputs. This could lead to biased research results and hence to suppressing of the efforts made by the researchers. This research was conducted in a selected site belonging to the Gonbad Agricultural Research Station, located in the semiarid region, northeastern Iran. The aim was to characterize the short-range spatial variability of the inherent and management-depended soil properties and to determine if this variation is large and can be managed at practical scales. The soils were sampled using a grid 55 m apart. In total, 100 composite soil samples were collected from topsoil (0-30 cm and were analyzed for calcium carbonate equivalent, organic carbon, clay, available phosphorus, available potassium, iron, copper, zinc and manganese. Descriptive statistics were applied to check data trends. Geostatistical analysis was applied to variography, model fitting and contour mapping. Sampling at 55 m made it possible to split the area of the selected experimental plot into relatively uniform areas that allow application of agricultural inputs with variable rates. Keywords: Short-range soil variability, Within-field soil variability, Interpolation, Precision agriculture, Geostatistics

  14. Saturated hydraulic conductivity model computed from bimodal water retention curves for a range of New Zealand soils

    Directory of Open Access Journals (Sweden)

    J. A. P. Pollacco

    2017-06-01

    Full Text Available Descriptions of soil hydraulic properties, such as the soil moisture retention curve, θ(h, and saturated hydraulic conductivities, Ks, are a prerequisite for hydrological models. Since the measurement of Ks is expensive, it is frequently derived from statistical pedotransfer functions (PTFs. Because it is usually more difficult to describe Ks than θ(h from pedotransfer functions, Pollacco et al. (2013 developed a physical unimodal model to compute Ks solely from hydraulic parameters derived from the Kosugi θ(h. This unimodal Ks model, which is based on a unimodal Kosugi soil pore-size distribution, was developed by combining the approach of Hagen–Poiseuille with Darcy's law and by introducing three tortuosity parameters. We report here on (1 the suitability of the Pollacco unimodal Ks model to predict Ks for a range of New Zealand soils from the New Zealand soil database (S-map and (2 further adaptations to this model to adapt it to dual-porosity structured soils by computing the soil water flux through a continuous function of an improved bimodal pore-size distribution. The improved bimodal Ks model was tested with a New Zealand data set derived from historical measurements of Ks and θ(h for a range of soils derived from sandstone and siltstone. The Ks data were collected using a small core size of 10 cm diameter, causing large uncertainty in replicate measurements. Predictions of Ks were further improved by distinguishing topsoils from subsoil. Nevertheless, as expected, stratifying the data with soil texture only slightly improved the predictions of the physical Ks models because the Ks model is based on pore-size distribution and the calibrated parameters were obtained within the physically feasible range. The improvements made to the unimodal Ks model by using the new bimodal Ks model are modest when compared to the unimodal model, which is explained by the poor accuracy of measured total porosity. Nevertheless, the new bimodal

  15. Saturated hydraulic conductivity model computed from bimodal water retention curves for a range of New Zealand soils

    Science.gov (United States)

    Pollacco, Joseph Alexander Paul; Webb, Trevor; McNeill, Stephen; Hu, Wei; Carrick, Sam; Hewitt, Allan; Lilburne, Linda

    2017-06-01

    Descriptions of soil hydraulic properties, such as the soil moisture retention curve, θ(h), and saturated hydraulic conductivities, Ks, are a prerequisite for hydrological models. Since the measurement of Ks is expensive, it is frequently derived from statistical pedotransfer functions (PTFs). Because it is usually more difficult to describe Ks than θ(h) from pedotransfer functions, Pollacco et al. (2013) developed a physical unimodal model to compute Ks solely from hydraulic parameters derived from the Kosugi θ(h). This unimodal Ks model, which is based on a unimodal Kosugi soil pore-size distribution, was developed by combining the approach of Hagen-Poiseuille with Darcy's law and by introducing three tortuosity parameters. We report here on (1) the suitability of the Pollacco unimodal Ks model to predict Ks for a range of New Zealand soils from the New Zealand soil database (S-map) and (2) further adaptations to this model to adapt it to dual-porosity structured soils by computing the soil water flux through a continuous function of an improved bimodal pore-size distribution. The improved bimodal Ks model was tested with a New Zealand data set derived from historical measurements of Ks and θ(h) for a range of soils derived from sandstone and siltstone. The Ks data were collected using a small core size of 10 cm diameter, causing large uncertainty in replicate measurements. Predictions of Ks were further improved by distinguishing topsoils from subsoil. Nevertheless, as expected, stratifying the data with soil texture only slightly improved the predictions of the physical Ks models because the Ks model is based on pore-size distribution and the calibrated parameters were obtained within the physically feasible range. The improvements made to the unimodal Ks model by using the new bimodal Ks model are modest when compared to the unimodal model, which is explained by the poor accuracy of measured total porosity. Nevertheless, the new bimodal model provides an

  16. Apatite ore mine tailings as an amendment for remediation of a lead-contaminated shooting range soil.

    Science.gov (United States)

    Venäläinen, Salla H

    2011-10-01

    This study investigated the use of tailings from apatite ore beneficiation in the remediation of a heavily contaminated shooting range soil. The tailings originating in Siilinjärvi carbonatite complex, Finland, consist of apatite residues accompanied by phlogopite and calcite. In a pot experiment, organic top layer of a boreal forest soil predisposed to pellet-derived lead (Pb) was amended with tailings of various particle-sizes (Ø>0.2mm, Øremediation technique at polluted sites. Copyright © 2011 Elsevier B.V. All rights reserved.

  17. Modeling Soil Water Retention Curves in the Dry Range Using the Hygroscopic Water Content

    DEFF Research Database (Denmark)

    Chen, Chong; Hu, Kelin; Arthur, Emmanuel

    2014-01-01

    Accurate information on the dry end (matric potential less than −1500 kPa) of soil water retention curves (SWRCs) is crucial for studying water vapor transport and evaporation in soils. The objectives of this study were to assess the potential of the Oswin model for describing the water adsorption...... curves of soils and to predict SWRCs at the dry end using the hygroscopic water content at a relative humidity of 50% (θRH50). The Oswin model yielded satisfactory fits to dry-end SWRCs for soils dominated by both 2:1 and 1:1 clay minerals. Compared with the Oswin model, the Campbell and Shiozawa model...... for soils dominated by 2:1 and 1:1 clays, respectively. Comparison of the Oswin model combined with the Kelvin equation, with water potential estimated from θRH50 (Oswin-KRH50), CS model combined with the Arthur equation (CS-A), and CS-K model, with water potential obtained from θRH50 (CS-KRH50) indicated...

  18. Effects of native and exotic range-expanding plant species on taxonomic and functional composition of nematodes in the soil food web

    NARCIS (Netherlands)

    Morrien, E.; Duyts, H.; Van der Putten, W.H.

    2012-01-01

    Due to climate warming, many plant species shift ranges towards higher latitudes. Plants can disperse faster than most soil biota, however, little is known about how range-expanding plants in the new range will establish interactions with the resident soil food web. In this paper we examine how the

  19. The effect of Cs-137 short-range spatial variability on soil after the Chernobyl disaster

    Science.gov (United States)

    Martynenko, Vladimir; Vakulovsky, Sergey; Linnik, Vitaly

    2014-05-01

    After the Chernobyl accident of 1986, large areas of Russia were contaminated by 137Cs. Post-depositional redistribution of 137Cs fallout across the land surface resulting from mechanical, physical, chemical, and biological processes operating in the soil system and the grain size selectivity associated with soil erosion and sediment transport processes. Therefore of uppermost importance are data on evaluating 137Cs variability at short distances, obtained at the early period after the accident. Measurements of 137Cs deposit at the territory of Russia exposed to radioactive contamination were mainly conducted with the help of air-gamma survey, and were verified by soil sampling on test plots with size 10x10 m with control soil sampling using "envelope" method of fivefold soil sampling (1 sampling at the centre and 4 along the edges of the plot under study). Presented here are evaluation data of 137Cs contamination, obtained in the Bryansk, Yaroslav and Rostov regions in 1991. Test plots were selected at the distance of 50-100 m away from a road on matted areas with undisturbed soil structure. Test routes of sampling were made perpendicularly to directions crossing basic traces of radioactive contamination. Sampling measurements were carried out at Canberra and Ortec gamma spectrometers. Each of the 5 samples of the "envelope" was measured separately, soil mixing was not applied. 137Cs value for the Bryansk Region varied from 2,6 kBq/m2 to 2294 kBq/m2, at the territories of the Yaroslav and Rostov regions 137Cs value varied from 0,44 kBq/m2 to 5,1 kBq/m2 and 0,56 kBq/m2 to 22,2 kBq/m2, respectively. Statistical analysis of 137Cs deposit at different plots is a solid argumentation in favour of nonuniform distribution in various landscapes and at a different distance from the Chernobyl NPP. Such nonuniformity of 137Cs soil contamination in the limits of 10 m of the plot is most likely to be related to initial aerosol contamination nonuniformity at the moment of

  20. Plant uptake and availability of antimony, lead, copper and zinc in oxic and reduced shooting range soil.

    Science.gov (United States)

    Hockmann, Kerstin; Tandy, Susan; Studer, Björn; Evangelou, Michael W H; Schulin, Rainer

    2018-03-19

    Shooting ranges polluted by antimony (Sb), lead (Pb), copper (Cu) and zinc (Zn) are used for animal grazing, thus pose a risk of contaminants entering the food chain. Many of these sites are subject to waterlogging of poorly drained soils. Using field lysimeter experiments, we compared Sb, Pb, Cu and Zn uptake by four common pasture plant species (Lolium perenne, Trifolium repens, Plantago lanceolata and Rumex obtusifolius) growing on a calcareous shooting range soil under waterlogged and drained conditions. To monitor seasonal trends, the same plants were collected at three times over the growing season. Additionally, variations in soil solution concentrations were monitored at three depths over the experiment. Under reducing conditions, soluble Sb concentrations dropped from ∼50 μg L -1 to ∼10 μg L -1 , which was attributed to the reduction of Sb(V) to Sb(III) and the higher retention of the trivalent species by the soil matrix. Shoot Sb concentrations differed by a factor of 60 between plant species, but remained at levels <0.3 μg g -1 . Despite the difference in soil solution concentrations between treatments, total Sb accumulation in shoots for plants collected on the waterlogged soil did not change, suggesting that Sb(III) was much more available for plant uptake than Sb(V), as only 10% of the total Sb was present as Sb(III). In contrast to Sb, Pb, Cu and Zn soil solution concentrations remained unaffected by waterlogging, and shoot concentrations were significantly higher in the drained treatment for many plant species. Although showing an increasing trend over the season, shoot metal concentrations generally remained below regulatory values for fodder plants (40 μg g -1  Pb, 150 μg g -1 Zn, 15-35 μg g -1 Cu), indicating a low risk of contaminant transfer into the food chain under both oxic and anoxic conditions for the type of shooting range soil investigated in this study. Copyright © 2018 Elsevier Ltd. All rights

  1. Nitrous Oxide Production in an Eastern Corn Belt Soil: Sources and Redox Range

    Science.gov (United States)

    Nitrous oxide (N2O) derived from soils is a main contributor to the greenhouse gas effect and a precursor to ozone-depleting substrates; however, the source processes and interacting controls are not well established. This study was conducted to estimate magnitude and source (nitrification vs. denit...

  2. Sr 90 behaviour in the soil-plant system of moors of the Gomel' range

    International Nuclear Information System (INIS)

    Kostereva, I.V.; Kudryashov, V.P.; Shamal', N.V.; Matusevich, Zh.L.

    2005-01-01

    The wavy dependence is installed between pH of the soil of moors and rate of accumulation (RA) of Sr 90 by phytomass of plants. The direct correlation is marked between concentration of mineral materials and RA of an above - ground part of herbaceous plants. Is abnormal high values RA are observed for the green forms of semifrutexs and undershrubs. (authors)

  3. Solubility of lead and copper in biochar-amended small arms range soils: influence of soil organic carbon and pH.

    Science.gov (United States)

    Uchimiya, Minori; Bannon, Desmond I

    2013-08-14

    Biochar is often considered a strong heavy metal stabilizing agent. However, biochar in some cases had no effects on, or increased the soluble concentrations of, heavy metals in soil. The objective of this study was to determine the factors causing some biochars to stabilize and others to dissolve heavy metals in soil. Seven small arms range soils with known total organic carbon (TOC), cation exchange capacity, pH, and total Pb and Cu contents were first screened for soluble Pb and Cu concentrations. Over 2 weeks successive equilibrations using weak acid (pH 4.5 sulfuric acid) and acetate buffer (0.1 M at pH 4.9), Alaska soil containing disproportionately high (31.6%) TOC had nearly 100% residual (insoluble) Pb and Cu. This soil was then compared with sandy soils from Maryland containing significantly lower (0.5-2.0%) TOC in the presence of 10 wt % (i) plant biochar activated to increase the surface-bound carboxyl and phosphate ligands (PS450A), (ii) manure biochar enriched with soluble P (BL700), and (iii) unactivated plant biochars produced at 350 °C (CH350) and 700 °C (CH500) and by flash carbonization (corn). In weak acid, the pH was set by soil and biochar, and the biochars increasingly stabilized Pb with repeated extractions. In pH 4.9 acetate buffer, PS450A and BL700 stabilized Pb, and only PS450A stabilized Cu. Surface ligands of PS450A likely complexed and stabilized Pb and Cu even under acidic pH in the presence of competing acetate ligand. Oppositely, unactivated plant biochars (CH350, CH500, and corn) mobilized Pb and Cu in sandy soils; the putative mechanism is the formation of soluble complexes with biochar-borne dissolved organic carbon. In summary, unactivated plant biochars can inadvertently increase dissolved Pb and Cu concentrations of sandy, low TOC soils when used to stabilize other contaminants.

  4. Microspatial ecotone dynamics at a shifting range limit: plant-soil variation across salt marsh-mangrove interfaces.

    Science.gov (United States)

    Yando, E S; Osland, M J; Hester, M W

    2018-05-01

    Ecotone dynamics and shifting range limits can be used to advance our understanding of the ecological implications of future range expansions in response to climate change. In the northern Gulf of Mexico, the salt marsh-mangrove ecotone is an area where range limits and ecotone dynamics can be studied in tandem as recent decreases in winter temperature extremes have allowed for mangrove expansion at the expense of salt marsh. In this study, we assessed aboveground and belowground plant-soil dynamics across the salt marsh-mangrove ecotone quantifying micro-spatial patterns in horizontal extent. Specifically, we studied vegetation and rooting dynamics of large and small trees, the impact of salt marshes (e.g. species and structure) on mangroves, and the influence of vegetation on soil properties along transects from underneath the mangrove canopy into the surrounding salt marsh. Vegetation and rooting dynamics differed in horizontal reach, and there was a positive relationship between mangrove tree height and rooting extent. We found that the horizontal expansion of mangrove roots into salt marsh extended up to eight meters beyond the aboveground boundary. Variation in vegetation structure and local hydrology appear to control mangrove seedling dynamics. Finally, soil carbon density and organic matter did not differ within locations across the salt marsh-mangrove interface. By studying aboveground and belowground variation across the ecotone, we can better predict the ecological effects of continued range expansion in response to climate change.

  5. Microspatial ecotone dynamics at a shifting range limit: plant–soil variation across salt marsh–mangrove interfaces

    Science.gov (United States)

    Yando, Erik S.; Osland, Michael J.; Hester, Mark H.

    2018-01-01

    Ecotone dynamics and shifting range limits can be used to advance our understanding of the ecological implications of future range expansions in response to climate change. In the northern Gulf of Mexico, the salt marsh–mangrove ecotone is an area where range limits and ecotone dynamics can be studied in tandem as recent decreases in winter temperature extremes have allowed for mangrove expansion at the expense of salt marsh. In this study, we assessed aboveground and belowground plant–soil dynamics across the salt marsh–mangrove ecotone quantifying micro-spatial patterns in horizontal extent. Specifically, we studied vegetation and rooting dynamics of large and small trees, the impact of salt marshes (e.g. species and structure) on mangroves, and the influence of vegetation on soil properties along transects from underneath the mangrove canopy into the surrounding salt marsh. Vegetation and rooting dynamics differed in horizontal reach, and there was a positive relationship between mangrove tree height and rooting extent. We found that the horizontal expansion of mangrove roots into salt marsh extended up to eight meters beyond the aboveground boundary. Variation in vegetation structure and local hydrology appear to control mangrove seedling dynamics. Finally, soil carbon density and organic matter did not differ within locations across the salt marsh-mangrove interface. By studying aboveground and belowground variation across the ecotone, we can better predict the ecological effects of continued range expansion in response to climate change.

  6. Charcoal and Total Carbon in Soils from Foothills Shrublands to Subalpine Forests in the Colorado Front Range

    Directory of Open Access Journals (Sweden)

    Robert Sanford

    2012-10-01

    Full Text Available Temperate conifer forests in the Colorado Front Range are fire-adapted ecosystems where wildland fires leave a legacy in the form of char and charcoal. Long-term soil charcoal C (CC pools result from the combined effects of wildland fires, aboveground biomass characteristics and soil transfer mechanisms. We measured CC pools in surface soils (0–10 cm at mid-slope positions on east facing aspects in five continuous foothills shrubland and conifer forest types. We found a significant statistical effect of vegetation type on CC pools along this ecological gradient, but not a linear pattern increasing with elevation gain. There is a weak bimodal pattern of CC gain with elevation between foothills shrublands (1.2 mg CC ha−1 and the lower montane, ponderosa pine (1.5 mg CC ha−1 and Douglas-fir (1.5 mg CC ha−1 forest types prior to a mid-elevation decline in upper montane lodgepole pine forests (1.2 mg CC ha−1 before increasing again in the spruce/subalpine fir forests (1.5 mg CC ha−1. We propose that CC forms and accumulates via unique ecological conditions such as fire regime. The range of soil CC amounts and ratios of CC to total SOC are comparable to but lower than other regional estimates.

  7. Long range transport of fine particle windblown soils and coal fired power station emissions into Hanoi between 2001 to 2008

    Energy Technology Data Exchange (ETDEWEB)

    Cohen, D.D.; Crawford, J.; Stelcer, E.; Vuong, T.B. [Australian Nuclear Science & Technology Organisation, Kirrawee DC, NSW (Australia)

    2010-10-15

    Fine particulate matter (PM2.5), source fingerprints and their contributions have been measured and reported previously at Hanoi, Vietnam, from 25 April 2001 to 31 December 2008. In this study back trajectories are used to identify long range transport into Hanoi for two of these sources, namely, windblown dust (Soil) from 12 major deserts in China and emissions from 33 coal fired power plants (Coal) in Vietnam and China. There were 28 days of extreme Soil events with concentrations greater than 6 {mu} g m{sup -3} and 25 days of extreme Coal with concentrations greater than 30 {mu} g m{sup -3} from a total of 748 sampling days during the study period. Through the use of back trajectories it was found that long range transport of soil from the Taklamakan and Gobi desert regions (more than 3000 km to the north west) accounted for 76% of the extreme events for Soil. The three local Vietnamese power stations contributed to 15% of the extreme Coal events, while four Chinese power stations between 300 km and 1700 km to the north-east of Hanoi contributed 50% of the total extreme Coal events measured at the Hanoi sampling site.

  8. Soil and geomorphological parameters to characterize natural environmental and human induced changes within the Guadarrama Range (Central Spain)

    Science.gov (United States)

    Schmid, Thomas; Inclán-Cuartas, Rosa M.; Santolaria-Canales, Edmundo; Saa, Antonio; Rodríguez-Rastrero, Manuel; Tanarro-Garcia, Luis M.; Luque, Esperanza; Pelayo, Marta; Ubeda, Jose; Tarquis, Ana; Diaz-Puente, Javier; De Marcos, Javier; Rodriguez-Alonso, Javier; Hernandez, Carlos; Palacios, David; Gallardo-Díaz, Juan; Fidel González-Rouco, J.

    2016-04-01

    to determine the physical and chemical soil properties. The parent material is gneiss andassociated deposits and, as a result, soils are acid. The soils have a low to medium organic matter content and are non-saline. They are moderately to well drained soils and have no or slight evidence of erosion. The soil within the high mountain area has clear evidence of frost heave that has a vertical displacement of the surface in the centimeter range. The stations within the lowland and mid mountain areas represent the most degraded sites as a result of the livestock keeping, whereas the high mountain area is mainly influenced by natural environmental conditions. These soil and geomorphological parameters will constitute a basis for site characterization in future studies regarding soil degradation; determining the interaction between soil, vegetation and atmosphere with respect to human induced activities (e.g. atmospheric contamination and effects of fires); determining the nitrogen and carbon cycles; and the influence of heavy metal contaminants in the soils.

  9. Soil Water Retention and Relative Permeability for Full Range of Saturation

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Z. F.

    2010-09-28

    Common conceptual models for unsaturated flow often rely on the oversimplified representation of medium pores as a bundle of cylindrical capillaries and assume that the matric potential is attributed to capillary forces only. The adsorptive surface forces are ignored. It is often assumed that aqueous flow is negligible when a soil is near or at the residual water content. These models are successful at high and medium water contents but often give poor results at low water contents. These models do not apply to conditions at which water content is less than the residual water content. We extend the lower bound of existing water-retention functions and conductivity models from residual water content to the oven-dry condition (i.e., zero water content) by defining a state-dependent, residual-water content for a soil drier than a critical value. Furthermore, a hydraulic conductivity model for smooth uniform spheres was modified by introducing a correction factor to describe the film flow-induced hydraulic conductivity for natural porous media. The total unsaturated hydraulic conductivity is the sum of those due to capillary and film flow. The extended retention and conductivity models were verified with six datasets from the literature. Results show that, when the soil is at high and intermediate water content, there is no difference between the un-extended and the extended models; when the soil is at low water content, the un-extended models overestimate the water content but under-estimate the conductivity while the extended models match the retention and conductivity measurements well.

  10. Soil criteria to protect terrestrial wildlife and open-range livestock from metal toxicity at mining sites.

    Science.gov (United States)

    Ford, Karl L; Beyer, W Nelson

    2014-03-01

    Thousands of hard rock mines exist in the western USA and in other parts of the world as a result of historic and current gold, silver, lead, and mercury mining. Many of these sites in the USA are on public lands. Typical mine waste associated with these sites are tailings and waste rock dumps that may be used by wildlife and open-range livestock. This report provides wildlife screening criteria levels for metals in soil and mine waste to evaluate risk and to determine the need for site-specific risk assessment, remediation, or a change in management practices. The screening levels are calculated from toxicity reference values based on maximum tolerable levels of metals in feed, on soil and plant ingestion rates, and on soil to plant uptake factors for a variety of receptors. The metals chosen for this report are common toxic metals found at mining sites: arsenic, cadmium, copper, lead, mercury, and zinc. The resulting soil screening values are well above those developed by the US Environmental Protection Agency. The difference in values was mainly a result of using toxicity reference values that were more specific to the receptors addressed rather than the most sensitive receptor.

  11. Capacities of Candidate Herbaceous Plants for Phytoremediation of Soil-based TNT and RDX on Ranges

    National Research Council Canada - National Science Library

    Best, Elly P; Smith, Thomas; Hagen, Frank L; Dawson, Jeffrey O; Torrey, Alan J

    2008-01-01

    .... In these experiments, plants were exposed for periods ranging from 55 to 83 days in the greenhouse, biomass and evapotranspiration characteristics were determined, and residues of explosives' parent...

  12. Potential value of phosphate compounds in enhancing immobilization and reducing bioavailability of mixed heavy metal contaminants in shooting range soil.

    Science.gov (United States)

    Seshadri, B; Bolan, N S; Choppala, G; Kunhikrishnan, A; Sanderson, P; Wang, H; Currie, L D; Tsang, Daniel C W; Ok, Y S; Kim, G

    2017-10-01

    Shooting range soils contain mixed heavy metal contaminants including lead (Pb), cadmium (Cd), and zinc (Zn). Phosphate (P) compounds have been used to immobilize these metals, particularly Pb, thereby reducing their bioavailability. However, research on immobilization of Pb's co-contaminants showed the relative importance of soluble and insoluble P compounds, which is critical in evaluating the overall success of in situ stabilization practice in the sustainable remediation of mixed heavy metal contaminated soils. Soluble synthetic P fertilizer (diammonium phosphate; DAP) and reactive (Sechura; SPR) and unreactive (Christmas Island; CPR) natural phosphate rocks (PR) were tested for Cd, Pb and Zn immobilization and later their mobility and bioavailability in a shooting range soil. The addition of P compounds resulted in the immobilization of Cd, Pb and Zn by 1.56-76.2%, 3.21-83.56%, and 2.31-74.6%, respectively. The reactive SPR significantly reduced Cd, Pb and Zn leaching while soluble DAP increased their leachate concentrations. The SPR reduced the bioaccumulation of Cd, Pb and Zn in earthworms by 7.13-23.4% and 14.3-54.6% in comparison with earthworms in the DAP and control treatment, respectively. Bioaccessible Cd, Pb and Zn concentrations as determined using a simplified bioaccessibility extraction test showed higher long-term stability of P-immobilized Pb and Zn than Cd. The differential effect of P-induced immobilization between P compounds and metals is due to the variation in the solubility characteristics of P compounds and nature of metal phosphate compounds formed. Therefore, Pb and Zn immobilization by P compounds is an effective long-term remediation strategy for mixed heavy metal contaminated soils. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Comparison of soil thickness in a zero-order basin in the Oregon Coast Range using a soil probe and electrical resistivity tomography

    Science.gov (United States)

    Morse, Michael S.; Lu, Ning; Godt, Jonathan W.; Revil, André; Coe, Jeffrey A.

    2012-01-01

    Accurate estimation of the soil thickness distribution in steepland drainage basins is essential for understanding ecosystem and subsurface response to infiltration. One important aspect of this characterization is assessing the heavy and antecedent rainfall conditions that lead to shallow landsliding. In this paper, we investigate the direct current (DC) resistivity method as a tool for quickly estimating soil thickness over a steep (33–40°) zero-order basin in the Oregon Coast Range, a landslide prone region. Point measurements throughout the basin showed bedrock depths between 0.55 and 3.2 m. Resistivity of soil and bedrock samples collected from the site was measured for degrees of saturation between 40 and 92%. Resistivity of the soil was typically higher than that of the bedrock for degrees of saturation lower than 70%. Results from the laboratory measurements and point-depth measurements were used in a numerical model to evaluate the resistivity contrast at the soil-bedrock interface. A decreasing-with-depth resistivity contrast was apparent at the interface in the modeling results. At the field site, three transects were surveyed where coincident ground truth measurements of bedrock depth were available, to test the accuracy of the method. The same decreasing-with-depth resistivity trend that was apparent in the model was also present in the survey data. The resistivity contour of between 1,000 and 2,000 Ωm that marked the top of the contrast was our interpreted bedrock depth in the survey data. Kriged depth-to-bedrock maps were created from both the field-measured ground truth obtained with a soil probe and interpreted depths from the resistivity tomography, and these were compared for accuracy graphically. Depths were interpolated as far as 16.5 m laterally from the resistivity survey lines with root mean squared error (RMSE) = 27 cm between the measured and interpreted depth at those locations. Using several transects and analysis of the subsurface

  14. The effects of organic matter-mineral interactions and organic matter chemistry on diuron sorption across a diverse range of soils.

    Science.gov (United States)

    Smernik, Ronald J; Kookana, Rai S

    2015-01-01

    Sorption of non-ionic organic compounds to soil is usually expressed as the carbon-normalized partition coefficient (KOC), because it is assumed that the main factor that influences the amount sorbed is the organic carbon content of the soil. However, KOC can vary by a factor of at least ten across a range of soils. We investigated two potential causes of variation in diuron KOC - organic matter-mineral interactions and organic matter chemistry - for a diverse set of 34 soils from Sri Lanka, representing a wide range of soil types. Treatment with hydrofluoric acid (HF-treatment) was used to concentrate soil organic matter. HF-treatment increased KOC for the majority of soils (average factor 2.4). We attribute this increase to the blocking of organic matter sorption sites in the whole soils by minerals. There was no significant correlation between KOC for the whole soils and KOC for the HF-treated soils, indicating that the importance of organic matter-mineral interactions varied greatly amongst these soils. There was as much variation in KOC across the HF-treated soils as there was across the whole soils, indicating that the nature of soil organic matter is also an important contributor to KOC variability. Organic matter chemistry, determined by solid-state (13)C nuclear magnetic resonance (NMR) spectroscopy, was correlated with KOC for the HF-treated soils. In particular, KOC increased with the aromatic C content (R=0.64, p=1×10(-6)), and decreased with O-alkyl C (R=-0.32, p=0.03) and alkyl C (R=-0.41, p=0.004) content. Copyright © 2014 Elsevier Ltd. All rights reserved.

  15. Counter-current acid leaching process for the removal of Cu, Pb, Sb and Zn from shooting range soil.

    Science.gov (United States)

    Lafond, Stéphanie; Blais, Jean-François; Mercier, Guy; Martel, Richard

    2013-01-01

    This research explores the performance of a counter-current leaching process (CCLP) for Cu, Pb, Sb and Zn extraction in a polluted shooting range soil. The initial metal concentrations in the soil were 1790 mg Cu/kg, 48,300 mg Pb/kg, 840 mg Sb/kg and 368 mg Zn/kg. The leaching process consisted of five one-hour acid leaching steps, which used 1 M H2SO4 + 4 M NaCl (20 degrees C, soil suspension = 100 g/L) followed by two water rinsing steps. Ten counter-current remediation cycles were completed and the average metal removal yields were 98.3 +/- 0.3% of Cu, 99.5 +/- 0.1% of Pb, 75.5 +/- 5.1% of Sb and 29.1 +/- 27.2% of Zn. The quality of metal leaching did not deteriorate throughout the 10 remediation cycles completed for this study. The CCLP reduced acid and salt use by approximately 68% and reduced water consumption by approximately 60%, exceeding reductions achieved by a standard acid leaching process.

  16. Sr isotope characterization of atmospheric inputs to soils along a climate gradient of the Chilean Coastal Range

    Science.gov (United States)

    Oeser, Ralf; Schuessler, Jan A.; Floor, Geerke H.; von Blanckenburg, Friedhelm

    2017-04-01

    The rate and degree of rock weathering controls the release, distribution, and cycling of mineral nutrients at the Earth's surface, being essential for developing and sustaining of ecosystems. Climate plays an important role as water flow and temperature determine both the biological community and activity, and also set the speed of weathering. Because of this double control by climate, the impact of biological activity on rock weathering and the feedbacks between the geosphere and the biosphere under different climatic conditions are not well understood. We explore the impact of biota on rock weathering in the four EarthShape primary study areas which are situated along the Chilean Coastal Range, featuring an outstanding vegetation gradient controlled by climate, ranging over 2000 km from hyper-arid, to temperate, to humid conditions. The study sites are within 80 km of the Pacific coast and are located in granitic lithology. Moreover, the sites were unglaciated during the last glacial maximum. However, as substrates get depleted in mineral nutrients, ecosystems are increasingly nourished by atmospheric inputs, sources, such as solutes contained in rain, dust, and volcanic ash. We aim to quantify the primary nutrient inputs to the ecosystem from these different potential sources. Radiogenic strontium (Sr) isotope ratios are a powerful tool to trace chemical weathering, soil formation, as well as cation provenance and mobility [1]. We determined 87Sr/86Sr ratios on bulk bedrock, saprolite, and soil and performed sequential extractions of the the easily bioavailable soil phases up to 2 m depth on two soil depth profiles in each of the four study sites. Our first results from the La Campana study site indicate that the radiogenic Sr isotope ratios of saprolite samples decrease from 0.70571 (n = 4) at the base of the profile to lower values of 0.70520 (n = 4) at the top of the immobile saprolite, indicating increasing biotite weathering. 87Sr/86Sr increases in the

  17. Seasonal microbial and nutrient responses during a 5-year reduction in the daily temperature range of soil in a Chihuahuan Desert ecosystem.

    Science.gov (United States)

    van Gestel, Natasja C; Dhungana, Nirmala; Tissue, David T; Zak, John C

    2016-01-01

    High daily temperature range of soil (DTRsoil) negatively affects soil microbial biomass and activity, but its interaction with seasonal soil moisture in regulating ecosystem function remains unclear. For our 5-year field study in the Chihuahuan Desert, we suspended shade cloth 15 cm above the soil surface to reduce daytime temperature and increase nighttime soil temperature compared to unshaded plots, thereby reducing DTRsoil (by 5 ºC at 0.2 cm depth) without altering mean temperatures. Microbial biomass production was primarily regulated by seasonal precipitation with the magnitude of the response dependent on DTRsoil. Reduced DTRsoil more consistently increased microbial biomass nitrogen (MBN; +38%) than microbial biomass carbon (MBC) with treatment responses being similar in spring and summer. Soil respiration depended primarily on soil moisture with responses to reduced DTRsoil evident only in wetter summer soils (+53%) and not in dry spring soils. Reduced DTRsoil had no effect on concentrations of dissolved organic C, soil organic matter (SOM), nor soil inorganic N (extractable NO3 (-)-N + NH4 (+)-N). Higher MBN without changes in soil inorganic N suggests faster N cycling rates or alternate sources of N. If N cycling rates increased without a change to external N inputs (atmospheric N deposition or N fixation), then productivity in this desert system, which is N-poor and low in SOM, could be negatively impacted with continued decreases in daily temperature range. Thus, the future N balance in arid ecosystems, under conditions of lower DTR, seems linked to future precipitation regimes through N deposition and regulation of soil heat load dynamics.

  18. Comparative Evaluation of Common Savannahgrass on a Range of Soils Subjected to Different Stresses I: Productivity and Quality

    Directory of Open Access Journals (Sweden)

    Raymond Springer

    2014-04-01

    Full Text Available Turfgrass growth, performance and quality are affected by abiotic stress factors and are of primary concern for persons managing turfgrass areas under seasonal tropical climates. Under these conditions, common Savannahgrass (SG may have a performance advantage over imported hybrid turfgrasses. A greenhouse study was conducted to comparatively evaluate the performance of tropical turfgrasses exposed to water and compaction related stresses across a range of soils, with or without the addition of a surface sand layer. Turfgrass productivity and quality was monitored over a four-month growth period. Clipping yield (CY was lower at the higher compaction effort for all turfgrasses, but across all stresses, drought (D and waterlogging (WL resulted in lower CY. Values were significantly lower under D. SG had the highest clipping yield across all soils. The chlorophyll index (CI was lower for all turfgrasses under water-induced stress compared to compaction stresses. SG had a significantly higher CI across all stress treatments. Correlation analysis showed a positive (r² = 0.420 and significant (p < 0.05 relationship between CY and CI. Similar to CI, stress type influenced turfgrass visual quality (VQ, with D stress, resulting in the lowest VQ rating among turfgrasses. Bermudagrass (BG had the lowest VQ across all stress treatments, whilst, comparatively, Zoysiagrass (ZG had significantly higher VQ under high compaction (HC, low compaction (LC and WL stress. Overall, SG showed a higher level of tolerance to applied stresses and warrants greater attention as a potential turfgrass under tropical conditions.

  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. Soil classification predicts differences in prokaryotic communities across a range of geographically distant soils once pH is accounted for

    OpenAIRE

    Morales, Sergio; Trouche, Blandine; Kaminsky, Rachel

    2017-01-01

    Agricultural land is typically managed based on visible plant life at the expense of the belowground majority. However, microorganisms mediate processes sustaining plant life and the soil environment. To understand the role of microbes we first must understand what controls soil microbial community assembly. We assessed the distribution and composition of prokaryotic communities from soils representing four geographic regions on the South Island of New Zealand. These soils are under three dif...

  1. Lead and copper immobilization in a shooting range soil using soybean stover- and pine needle-derived biochars: Chemical, microbial and spectroscopic assessments

    Energy Technology Data Exchange (ETDEWEB)

    Ahmad, Mahtab [Korea Biochar Research Center & Department of Biological Environment, Kangwon National University, Chuncheon 200-701 (Korea, Republic of); Soil Sciences Department, College of Food and Agricultural Sciences, King Saud University, PO Box 2460, Riyadh 11451 (Saudi Arabia); Ok, Yong Sik; Rajapaksha, Anushka Upamali; Lim, Jung Eun [Korea Biochar Research Center & Department of Biological Environment, Kangwon National University, Chuncheon 200-701 (Korea, Republic of); Kim, Byung-Yong; Ahn, Jae-Hyung [Agricultural Microbiology Division, National Academy of Agricultural Science, Rural Development Administration, Wanju 565-851 (Korea, Republic of); Lee, Young Han [Division of Plant Environment Research, Gyeongsangnam-do Agricultural Research and Extension Service, Jinju 660-360 (Korea, Republic of); Al-Wabel, Mohammad I [Soil Sciences Department, College of Food and Agricultural Sciences, King Saud University, PO Box 2460, Riyadh 11451 (Saudi Arabia); Lee, Sung-Eun, E-mail: selpest@knu.ac.kr [School of Applied Biosciences, Kyungpook National University, Daegu 702-701 (Korea, Republic of); Lee, Sang Soo, E-mail: sslee97@kangwon.ac.kr [Korea Biochar Research Center & Department of Biological Environment, Kangwon National University, Chuncheon 200-701 (Korea, Republic of)

    2016-01-15

    Highlights: • Biochar immobilizes Pb and Cu in a contaminated shooting range soil. • Soybean stover-biochar is an efficient metal immobilizer than pine needle-biochar. • Biochar produced at 700 °C showed significant potential of sequestering C in soil. • Biochar showed less impact on the bacterial community than feedstock biomass. - Abstract: Biochar (BC) could be a potential candidate for the remediation of metal contaminated soil. Mechanistic understandings are needed for the appropriate selection of BC and investigating molecular microbial ecological interactions. The soybean stover-derived BCs were more effective in immobilizing Pb (88%) and Cu (87%) than the pine needle-derived BCs in a contaminated shooting range soil. The sequential chemical extractions indicated that BCs stimulated the geochemical transformation of metal species. Spectroscopic investigations using scanning electron microscopic elemental dot mapping and extended X-ray absorption fine structure spectroscopic measurements showed that Pb in the BCs amended soils was immobilized by the formation of stable chloropyromorphite. Soil organic C and microbial activity were also enhanced by BC. The non-labile C fraction in the soil amended with BCs produced at 700 °C was increased. Biochars showed less impact on the bacterial community than feedstock biomass as promulgated by the pyrosequencing of 16S rRNA gene. The feedstock type (namely soybean stover and pine needles) was the main factor influencing the BCs efficacy on metals’ (im) mobilization and bacterial health in soils.

  2. Lead and copper immobilization in a shooting range soil using soybean stover- and pine needle-derived biochars: Chemical, microbial and spectroscopic assessments

    International Nuclear Information System (INIS)

    Ahmad, Mahtab; Ok, Yong Sik; Rajapaksha, Anushka Upamali; Lim, Jung Eun; Kim, Byung-Yong; Ahn, Jae-Hyung; Lee, Young Han; Al-Wabel, Mohammad I; Lee, Sung-Eun; Lee, Sang Soo

    2016-01-01

    Highlights: • Biochar immobilizes Pb and Cu in a contaminated shooting range soil. • Soybean stover-biochar is an efficient metal immobilizer than pine needle-biochar. • Biochar produced at 700 °C showed significant potential of sequestering C in soil. • Biochar showed less impact on the bacterial community than feedstock biomass. - Abstract: Biochar (BC) could be a potential candidate for the remediation of metal contaminated soil. Mechanistic understandings are needed for the appropriate selection of BC and investigating molecular microbial ecological interactions. The soybean stover-derived BCs were more effective in immobilizing Pb (88%) and Cu (87%) than the pine needle-derived BCs in a contaminated shooting range soil. The sequential chemical extractions indicated that BCs stimulated the geochemical transformation of metal species. Spectroscopic investigations using scanning electron microscopic elemental dot mapping and extended X-ray absorption fine structure spectroscopic measurements showed that Pb in the BCs amended soils was immobilized by the formation of stable chloropyromorphite. Soil organic C and microbial activity were also enhanced by BC. The non-labile C fraction in the soil amended with BCs produced at 700 °C was increased. Biochars showed less impact on the bacterial community than feedstock biomass as promulgated by the pyrosequencing of 16S rRNA gene. The feedstock type (namely soybean stover and pine needles) was the main factor influencing the BCs efficacy on metals’ (im) mobilization and bacterial health in soils.

  3. Least Limiting Water Range and Load Bearing Capacity of Soil under Types of Tractor-Trailers for Mechanical Harvesting of Green Sugarcane

    Directory of Open Access Journals (Sweden)

    Antonio Higino Frederico Pereira

    2015-12-01

    Full Text Available ABSTRACT The expansion of the sugarcane industry in Brazil has intensified the mechanization of agriculture and caused effects on the soil physical quality. The purpose of this study was to evaluate the limiting water range and soil bearing capacity of a Latossolo Vermelho distroférrico típico (Rhodic Hapludox under the influence of different tractor-trailers used in mechanical sugarcane harvesting. The experiment was arranged in a randomized block design with five replications. The treatments consisted of green sugarcane harvesting with: harvester without trailer (T1; harvester with two trailers with a capacity of 10 Mg each (T2; harvester with trailer with a capacity of 20 Mg (T3 and harvester and truck with trailer with a capacity of 20 Mg (10 Mg per compartment (T4. The least limiting water range and soil bearing capacity were evaluated. The transport equipment to remove the harvested sugarcane from the field (trailer at harvest decreased the least limiting water range, reducing the structural soil quality. The truck trailer caused the greatest impact on the soil physical properties studied. The soil load bearing capacity was unaffected by the treatments, since the pressure of the harvester (T1 exceeded the pre-consolidation pressure of the soil.

  4. Spatial control of groundwater contamination, using principal ...

    Indian Academy of Sciences (India)

    probe into the spatial controlling processes of groundwater contamination, using principal component analysis (PCA). ... topography, soil type, depth of water levels, and water usage. Thus, the ... of effective sites for infiltration of recharge water.

  5. Structural composition of organic matter in particle-size fractions of soils along a climo-biosequence in the main range of Peninsular Malaysia

    Science.gov (United States)

    Jafarzadeh-Haghighi, Amir Hossein; Shamshuddin, Jusop; Hamdan, Jol; Zainuddin, Norhazlin

    2016-09-01

    Information on structural composition of organic matter (OM) in particle-size fractions of soils along a climo-biosequence is sparse. The objective of this study was to examine structural composition and morphological characteristics of OM in particle-size fractions of soils along a climo-biosequence in order to better understand the factors and processes affecting structural composition of soil organic matter. To explore changes in structural composition of OM in soils with different pedogenesis, the A-horizon was considered for further analyses including particle-size fractionation, solid-state 13C nuclear magnetic resonance (NMR) spectroscopy and scanning electron microscopy (SEM). Due to the increase in the thickness of organic layer with increasing elevation, the A-horizon was situated at greater depth in soils of higher elevation. The relationship between relative abundances of carbon (C) structures and particle-size fractions was examined using principal component analysis (PCA). It was found that alkyl C (20.1-73.4%) and O-alkyl C (16.8-67.7%) dominated particle-size fractions. The proportion of alkyl C increased with increasing elevation, while O-alkyl C showed an opposite trend. Results of PCA confirmed this finding and showed the relative enrichment of alkyl C in soils of higher elevation. Increase in the proportion of alkyl C in 250-2000 μm fraction is linked to selective preservation of aliphatic compounds derived from root litter. SEM results showed an increase in root contribution to the 250-2000 μm fraction with increasing elevation. For the changes in structural composition of OM in particle-size fractions of soils along the studied climo-biosequence are attributed to site-specific differences in pedogenesis as a function of climate and vegetation.

  6. Evaluation of soil metal bioavailability estimates using two plant species (L. perenne and T. aestivum) grown in a range of agricultural soils treated with biosolids and metal salts

    International Nuclear Information System (INIS)

    Black, Amanda; McLaren, Ronald G.; Reichman, Suzanne M.; Speir, Thomas W.; Condron, Leo M.

    2011-01-01

    Few studies have quantified the accuracy of soil metal bioavailability assays using large datasets. A meta-analysis from experiments spanning 6 months to 13 years on 12 soil types, compared bioavailability estimate efficiencies for wheat and ryegrass. Treatments included biosolids ± metals, comparing total metal, Ca(NO 3 ) 2 , EDTA, soil solution, DGT and free ion activity. The best correlations between soil metal bioavailability and shoot concentrations were for Ni using Ca(NO 3 ) 2 (r 2 = 0.72) which also provided the best estimate of Zn bioavailability (r 2 = 0.64). DGT provided the best estimate of Cd bioavailability, accounting for 49% of shoot Cd concentrations. There was no reliable descriptor of Cu bioavailability, with less than 35% of shoot Cu concentrations defined. Thus interpretation of data obtained from many soil metal bioavailability assays is unreliable and probably flawed, and there is little justification to look beyond Ca(NO 3 ) 2 for Ni and Zn, and DGT for Cd. - Highlights: → A meta-analysis evaluated the efficacy of soil metal bioavailability assays. → DGT could explain 49% of shoot Cd concentration. → There is little justification to look beyond Ca(NO 3 ) 2 for Ni and Zn. - A meta-analysis of soil metal bioavailability estimates for 12 soil types concluded that there is little justification to look beyond Ca(NO 3 ) 2 for Ni and Zn, and DGT for Cd.

  7. Evaluation of soil metal bioavailability estimates using two plant species (L. perenne and T. aestivum) grown in a range of agricultural soils treated with biosolids and metal salts

    Energy Technology Data Exchange (ETDEWEB)

    Black, Amanda, E-mail: amanda.black@lincoln.ac.nz [Department of Soil and Physical Sciences, Faculty of Agriculture and Life Sciences, Lincoln University, PO Box 84, Lincoln 7647, Christchurch (New Zealand); McLaren, Ronald G. [Department of Soil and Physical Sciences, Faculty of Agriculture and Life Sciences, Lincoln University, PO Box 84, Lincoln 7647, Christchurch (New Zealand); Reichman, Suzanne M. [School of Civil, Environmental and Chemical Engineering, RMIT University, GPO Box 2476, Melbourne 3001 (Australia); Speir, Thomas W. [Institute of Environmental Science and Research Ltd (ESR), PO Box 50348, Porirua 5240 (New Zealand); Condron, Leo M. [Department of Soil and Physical Sciences, Faculty of Agriculture and Life Sciences, Lincoln University, PO Box 84, Lincoln 7647, Christchurch (New Zealand)

    2011-06-15

    Few studies have quantified the accuracy of soil metal bioavailability assays using large datasets. A meta-analysis from experiments spanning 6 months to 13 years on 12 soil types, compared bioavailability estimate efficiencies for wheat and ryegrass. Treatments included biosolids {+-} metals, comparing total metal, Ca(NO{sub 3}){sub 2}, EDTA, soil solution, DGT and free ion activity. The best correlations between soil metal bioavailability and shoot concentrations were for Ni using Ca(NO{sub 3}){sub 2} (r{sup 2} = 0.72) which also provided the best estimate of Zn bioavailability (r{sup 2} = 0.64). DGT provided the best estimate of Cd bioavailability, accounting for 49% of shoot Cd concentrations. There was no reliable descriptor of Cu bioavailability, with less than 35% of shoot Cu concentrations defined. Thus interpretation of data obtained from many soil metal bioavailability assays is unreliable and probably flawed, and there is little justification to look beyond Ca(NO{sub 3}){sub 2} for Ni and Zn, and DGT for Cd. - Highlights: > A meta-analysis evaluated the efficacy of soil metal bioavailability assays. > DGT could explain 49% of shoot Cd concentration. > There is little justification to look beyond Ca(NO{sub 3}){sub 2} for Ni and Zn. - A meta-analysis of soil metal bioavailability estimates for 12 soil types concluded that there is little justification to look beyond Ca(NO{sub 3}){sub 2} for Ni and Zn, and DGT for Cd.

  8. Integrating quantitative morphological and qualitative molecular methods to analyse soil nematode community responses to plant range expansion

    NARCIS (Netherlands)

    Geisen, S.; Snoek, B.; Ten Hooven, F.C.; Duyts, H.; Kostenko, O.; Bloem, Janneke; Martens, H.J.; Quist, C.W.; Helder, Johannes; van der Putten, W.H.

    2018-01-01

    Below‐ground nematodes are important for soil functioning, as they are ubiquitous and operate at various trophic levels in the soil food web. However, morphological nematode community analysis is time consuming and requires ample training. qPCR‐based nematode identification techniques are well

  9. Heterogeneity of elemental composition and natural abundance of stables isotopes of C and N in soils and leaves of mangroves at their southernmost West Atlantic range.

    Science.gov (United States)

    Tognella, M M P; Soares, M L G; Cuevas, E; Medina, E

    2016-01-01

    Mangrove communities were selected in the state of Santa Catarina, Brazil, near their southernmost limit of distribution, to study mineral nutrient relation in soils and plants. Communities included three true mangrove species, Rhizophora mangle, Laguncularia racemosa and Avicennia germinans, and two associated species, the fern Acrostichum danaeifolium, and the grass Spartina densiflora. The sites included communities in the lower Río Tavares near Florianopolis city, Sonho beach near Palhoça city, and the Santo Antonio lagoon. These sites included a full range of mangroves under humid climate where winter temperatures, instead of salinity, may be the main factor regulating their productive capacity and species composition. Soil salinity was determined by the concentration of soluble Na, and soil C and N were linearly correlated indicating their association in organic matter. Tavares site showed higher specific conductivity, and concentrations of Na and Mg in the soil layer below 40 cm depth, indicating larger influence of marine water. Isotopic signature of C increased with soil depth suggesting that microorganisms decomposing organic matter are releasing 13C depleted CO2. Nitrogen isotopic signature decreased with soil depth, indicating enrichment in 15N possibly as a result of denitrification in the upper soil layers. Mineral elements in leaf tissues showed A. schaueriana with higher concentrations of N, P, Na, K, Cu, Zn, and Na/Ca ratio. Spartina densiflora was characterized by the lowest N and K concentrations, and the highest concentrations of Al and Fe. Rhizophora mangle and L. racemosa had the highest Ca concentrations. Carbon isotopic signatures identified S. densiflora as a C4 plant, and A. schaueriana as the mangrove species occupying comparatively more water stressed microsites than the rest. Leaf nitrogen isotopic signatures were positive, in correspondence with the soil values. The results support the hypothesis that sites sampled were comparatively

  10. Feasibility/treatability studies for removal of heavy metals from training range soils at the Grafenwoehr Training Area, Germany

    Energy Technology Data Exchange (ETDEWEB)

    Peters, R.W.

    1995-05-01

    A feasibility/treatability study was performed to investigate the leaching potential of heavy metals (particularly lead) from soils at the Grafenw6hr Training Area (GTA) in Germany. The study included an evaluation of the effectiveness of chelant extraction to remediate the heavy-metal-contarninated soils. Batch shaker tests indicated that ethylenediaminetetraacetic acid (EDTA) (0.01M) was more effective than citric acid (0.01M) at removing cadmium, copper, lead, and zinc. EDTA and citric acid were equally effective in mobilizing chromium and barium from the soil. The batch shaker technique with chelant extraction offers promise as a remediation technique for heavy-metal-contaninated soil at the GTA. Columnar flooding tests conducted as part of the study revealed that deionized water was the least effective leaching solution for mobilization of the heavy metals; the maximum solubilization obtained was 3.72% for cadmium. EDTA (0.05M) achieved the greatest removal of lead (average removal of 17.6%). The difficulty of extraction using deionized water indicates that all of the heavy metals are very tightly bound to the soil; therefore, they are very stable in the GTA soils and do not pose a serious threat to the groundwater system. Columnar flooding probably does not represent a viable remediation technique for in-situ cleanup of heavy-metal-contaminated soils at the GTA.

  11. The effect of kauri (Agathis australis) on grain size distribution and clay mineralogy of andesitic soils in the Waitakere Ranges, New Zealand

    NARCIS (Netherlands)

    Jongkind, A.G.; Buurman, P.

    2006-01-01

    Kauri (Agathis australis) is generally associated with intense podzolisation, but little research has been carried out to substantiate this. We studied soil profiles, grain size distribution patterns and clay mineralogy under kauri and broadleaf/tree fern vegetation in the Waitakere Ranges, North

  12. The relative influence of electrokinetic remediation design on the removal of As, Cu, Pb and Sb from shooting range soils

    DEFF Research Database (Denmark)

    Pedersen, Kristine B.; Jensen, Pernille Erland; Ottosen, Lisbeth M.

    2018-01-01

    to simultaneously optimise the removal by applying a stirred set-up, placement of the anode directly in the soil suspension, sieving the soil (analysis is a valuable tool for evaluating remediation measures depending soil...... and analysis was applied for assessing the efficiency of electrodialytic remediation treatment and variable importance varied for each of the studied metals. In general, applying a stirred set-up improved the metal removal, acidification time and reduced the energy consumption. The placement of the anode...... directly in the soil did not significantly influence the removal of Al, Mg, Mn, As and Pb, while moderately influencing the removal of Cu. Multivariate analysis (projections onto latent structures) revealed similar variable importance and optimal settings for removal of Cu and Pb. It is hence possible...

  13. Fractionation of metals by sequential extraction procedures (BCR and Tessier) in soil exposed to fire of wide temperature range

    Science.gov (United States)

    Fajkovic, Hana; Rončević, Sanda; Nemet, Ivan; Prohić, Esad; Leontić-Vazdar, Dana

    2017-04-01

    Forest fire presents serious problem, especially in Mediterranean Region. Effects of fire are numerous, from climate change and deforestation to loss of soil organic matter and changes in soil properties. One of the effects, not well documented, is possible redistribution and/or remobilisation of pollutants previously deposited in the soil, due to the new physical and chemical soil properties and changes in equilibrium conditions. For understanding and predicting possible redistribution and/or remobilisation of potential pollutants from soil, affected by fire different in temperature, several laboratory investigations were carried out. To evaluate the influence of organic matter on soil under fire, three soil samples were analysed and compared: (a) the one with added coniferous organic matter; (b) deciduous organic matter (b) and (c) soil without additional organic matter. Type of organic matter is closely related to pH of soil, as pH is influencing the mobility of some pollutants, e.g. metals. For that reason pH was also measured through all experimental steps. Each of mentioned soil samples (a, b and c) were heated at 1+3 different temperatures (25°C, 200°C, 500°C and 850°C). After heating, whereby fire effect on soil was simulated, samples were analysed by BCR protocol with the addition of a first step of sequential extraction procedure by Tessier and analysis of residual by aqua regia. Element fractionation of heavy metals by this procedure was used to determine the amounts of selected elements (Al, Cd, Cr, Co, Cu, Fe, Mn, Ni, Pb and Zn). Selected metal concentrations were determined using inductively coupled plasma atomic emission spectrometer. Further on, loss of organic matter was calculated after each heating procedure as well as the mineral composition. The mineral composition was determined using an X-ray diffraction. From obtained results, it can be concluded that temperature has an influence on concentration of elements in specific step of

  14. Soil Bacterial and Fungal Community Structure Across a Range of Unimproved and Semi-Improved Upland Grasslands

    OpenAIRE

    Kennedy, Nabla; Edwards, Suzanne; Clipson, Nicholas

    2005-01-01

    Changes in soil microbial community structure due to improvement are often attributed to concurrent shifts in floristic community composition. The bacterial and fungal communities of unimproved and semi-improved (as determined by floristic classification) grassland soils were studied at five upland sites on similar geological substrata using both broad-scale (microbial activity and fungal biomass) and molecular [terminal restriction fragment length polymorphism (TRFLP)...

  15. Soil

    International Nuclear Information System (INIS)

    Freudenschuss, A.; Huber, S.; Riss, A.; Schwarz, S.; Tulipan, M.

    2002-01-01

    Environmental soil surveys in each province of Austria have been performed, soils of about 5,000 sites were described and analyzed for nutrients and pollutants, the majority of these data are recorded in the soil information system of Austria (BORIS) soil database, http://www.ubavie.gv.at/umweltsituation/boden/boris), which also contains a soil map of Austria, data from 30 specific investigations mainly in areas with industry and results from the Austria - wide cesium investigation. With respect to the environmental state of soils a short discussion is given, including two geographical charts, one showing which sites have soil data (2001) and the other the cadmium distribution in top soils according land use (forest, grassland, arable land, others). Information related to the soil erosion, Corine land cover (Europe-wide land cover database), evaluation of pollutants in soils (reference values of As, Cd, Co, Cr, Cu, Hg, Mo, Ni, Se, Pb, Tl, Va, Zn, AOX, PAH, PCB, PCDD/pcdf, dioxin), and relevant Austrian and European standards and regulations is provided. Figs. 2, Tables 4. (nevyjel)

  16. Análise dos componentes principais e métodos multicritério ordinais no estudo de organossolos e solos afins Principal component analysis and ordinal multicriteria methods to study organosols and related soils

    Directory of Open Access Journals (Sweden)

    Gustavo Souza Valladares

    2008-02-01

    SBCS (Brazilian Soil Science Society; the analytical methods proposed by EMBRAPA-Solos were used to characterize the soils. The principal component analysis was used to cluster the profiles based on morphological, physical, chemical and environmental attributes and proved adequate to group the soils under study based on the profile attributes and the grouping was well related to their taxonomy. The soil profiles were ranked by the ordinal multicriteria methods of Border, Condorcet and Copeland based on the subsidence risk. Results indicated a correlation between the methods (with exception of the Condorcet approach, unsuitable to rank the alternatives and the minimum residue, which is the classical parameter for the evaluation of subsidence, indicating efficacy to rank/classify the soil profiles in relation to subsidence risk. The quantitative approaches used are promising as evaluation tools in soil science studies.

  17. 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.)

  18. Exploring the Validity Range of the Polarimetric Two-Scale Two-Component Model for Soil Moisture Retrieval by Using AGRISAR Data

    Science.gov (United States)

    Di Martino, Gerardo; Iodice, Antonio; Natale, Antonio; Riccio, Daniele; Ruello, Giuseppe

    2015-04-01

    The recently proposed polarimetric two-scale two- component model (PTSTCM) in principle allows us obtaining a reasonable estimation of the soil moisture even in moderately vegetated areas, where the volumetric scattering contribution is non-negligible, provided that the surface component is dominant and the double-bounce component is negligible. Here we test the PTSTCM validity range by applying it to polarimetric SAR data acquired on areas for which, at the same times of SAR acquisitions, ground measurements of soil moisture were performed. In particular, we employ the AGRISAR'06 database, which includes data from several fields covering a period that spans all the phases of vegetation growth.

  19. Interactions between cadmium and lead with acidic soils: Experimental evidence of similar adsorption patterns for a wide range of metal concentrations and the implications of metal migration

    International Nuclear Information System (INIS)

    Pokrovsky, O.S.; Probst, A.; Leviel, E.; Liao, B.

    2012-01-01

    Highlights: ► Adsorption experiments of Cd and Pb in acid soils (China, France). ► Large pH conditions and large range of metal concentrations were considered. ► Similar dependencies between metals concentration in solution and metal adsorbed on the surface were predicted using Langmuir and Freundlich equations and surface complexation model (SCM). ► No competition between Cd and Pb detected at pH 5. ► Metal adsorption capacity is two orders of magnitude higher than limit value for soil protection. - Abstract: The importance of high- and low-affinity surface sites for cadmium and lead adsorption in typical European and Asian soils was investigated. Adsorption experiments on surface and deep horizons of acidic brown (Vosges, France) and red loess soils (Hunan, China) were performed at 25 °C as a function of the pH (3.5–8) and a large range of metal concentrations in solution (10 −9 –10 −4 mol l −1 ). We studied the adsorption kinetics using a Cd 2+ -selective electrode and desorption experiments as a function of the solid/solution ratio and pH. At a constant solution pH, all samples exhibited similar maximal adsorption capacities (4.0 ± 0.5 μmol/g Cd and 20 ± 2 μmol/g Pb). A constant slope of adsorbed–dissolved concentration dependence was valid over 5 orders of magnitude of metal concentrations. Universal Langmuir and Freundlich equations and the SCM formalism described the adsorption isotherms and the pH-dependent adsorption edge over very broad ranges of metal concentrations, indicating no high- or low-affinity sites for metal binding at the soil surface under these experimental conditions. At pH 5, Cd and Pb did not compete, in accordance with the SCM. The metal adsorption ability exceeded the value for soil protection by two orders of magnitude, but only critical load guarantees soil protection since metal toxicity depends on metal availability.

  20. Heterogeneity of elemental composition and natural abundance of stables isotopes of C and N in soils and leaves of mangroves at their southernmost West Atlantic range

    Directory of Open Access Journals (Sweden)

    M. M. P. Tognella

    Full Text Available Abstract Mangrove communities were selected in the state of Santa Catarina, Brazil, near their southernmost limit of distribution, to study mineral nutrient relation in soils and plants. Communities included three true mangrove species, Rhizophora mangle, Laguncularia racemosa and Avicennia germinans, and two associated species, the fern Acrostichum danaeifolium, and the grass Spartina densiflora. The sites included communities in the lower Río Tavares near Florianopolis city, Sonho beach near Palhoça city, and the Santo Antonio lagoon. These sites included a full range of mangroves under humid climate where winter temperatures, instead of salinity, may be the main factor regulating their productive capacity and species composition. Soil salinity was determined by the concentration of soluble Na, and soil C and N were linearly correlated indicating their association in organic matter. Tavares site showed higher specific conductivity, and concentrations of Na and Mg in the soil layer below 40 cm depth, indicating larger influence of marine water. Isotopic signature of C increased with soil depth suggesting that microorganisms decomposing organic matter are releasing 13C depleted CO2. Nitrogen isotopic signature decreased with soil depth, indicating enrichment in 15N possibly as a result of denitrification in the upper soil layers. Mineral elements in leaf tissues showed A. schaueriana with higher concentrations of N, P, Na, K, Cu, Zn, and Na/Ca ratio. Spartina densiflora was characterized by the lowest N and K concentrations, and the highest concentrations of Al and Fe. Rhizophora mangle and L. racemosa had the highest Ca concentrations. Carbon isotopic signatures identified S. densiflora as a C4 plant, and A. schaueriana as the mangrove species occupying comparatively more water stressed microsites than the rest. Leaf nitrogen isotopic signatures were positive, in correspondence with the soil values. The results support the hypothesis that

  1. Redesigning Principal Internships: Practicing Principals' Perspectives

    Science.gov (United States)

    Anast-May, Linda; Buckner, Barbara; Geer, Gregory

    2011-01-01

    Internship programs too often do not provide the types of experiences that effectively bridge the gap between theory and practice and prepare school leaders who are capable of leading and transforming schools. To help address this problem, the current study is directed at providing insight into practicing principals' views of the types of…

  2. What Motivates Principals?

    Science.gov (United States)

    Iannone, Ron

    1973-01-01

    Achievement and recognition were mentioned as factors appearing with greater frequency in principal's job satisfactions; school district policy and interpersonal relations were mentioned as job dissatisfactions. (Editor)

  3. Principal Ports and Facilities

    Data.gov (United States)

    California Natural Resource Agency — The Principal Port file contains USACE port codes, geographic locations (longitude, latitude), names, and commodity tonnage summaries (total tons, domestic, foreign,...

  4. Principal Ports and Facilities

    Data.gov (United States)

    California Department of Resources — The Principal Port file contains USACE port codes, geographic locations (longitude, latitude), names, and commodity tonnage summaries (total tons, domestic, foreign,...

  5. Principals' Perceptions of Politics

    Science.gov (United States)

    Tooms, Autumn K.; Kretovics, Mark A.; Smialek, Charles A.

    2007-01-01

    This study is an effort to examine principals' perceptions of workplace politics and its influence on their productivity and efficacy. A survey was used to explore the perceptions of current school administrators with regard to workplace politics. The instrument was disseminated to principals serving public schools in one Midwestern state in the…

  6. Renewing the Principal Pipeline

    Science.gov (United States)

    Turnbull, Brenda J.

    2015-01-01

    The work principals do has always mattered, but as the demands of the job increase, it matters even more. Perhaps once they could maintain safety and order and call it a day, but no longer. Successful principals today must also lead instruction and nurture a productive learning community for students, teachers, and staff. They set the tone for the…

  7. Plant-soil biota interactions and spatial distribution of black cherry in its native and invasive ranges

    NARCIS (Netherlands)

    Reinhart, K.O.; Packer, A.; Van der Putten, W.H.; Clay, K.A.

    2003-01-01

    One explanation for the higher abundance of invasive species in their non-native than native ranges is the escape from natural enemies. But there are few experimental studies comparing the parallel impact of enemies (or competitors and mutualists) on a plant species in its native and invaded ranges,

  8. Constructing principals' professional identities through life stories ...

    African Journals Online (AJOL)

    The Life History approach was used to collect data from six ... experience as the most significant leadership factors that influence principals' ... ranging from their entry into the teaching profession to their appointment as ..... teachers. I think I learnt from my principal to be strict but accommodating ..... Teachers College Press.

  9. Should Principals Know More about Law?

    Science.gov (United States)

    Doctor, Tyrus L.

    2013-01-01

    Educational law is a critical piece of the education conundrum. Principals reference law books on a daily basis in order to address the wide range of complex problems in the school system. A principal's knowledge of law issues and legal decision-making are essential to provide effective feedback for a successful school.

  10. Attenuation coefficients of soils and some building materials of Bangladesh in the energy range 276-1332 keV

    International Nuclear Information System (INIS)

    Alam, M.N.; Miah, M.M.H.; Chowdhury, M.I.; Kamal, M.; Ghose, S.; Rahman, Runi

    2001-01-01

    The linear and mass attenuation coefficients of different types of soil, sand, building materials and heavy beach mineral samples from the Chittagong and Cox's Bazar area of Bangladesh were measured using a high-resolution HPGe detector and the γ-ray energies 276.1, 302.8, 356.0, 383.8, 661.6 and 1173.2 and 1332.5 keV emitted from point sources of 133 Ba, 137 Cs and 60 Co, respectively. The linear attenuation coefficients show a linear relationship with the corresponding densities of the samples studied. The variations of the mass attenuation coefficient with γ-ray energy were exponential in nature. The measured mass attenuation coefficient values were compared with measurements made in other countries for similar kinds of materials. The values are in good agreement with each other in most cases

  11. Stabilization of Pb²⁺ and Cu²⁺ contaminated firing range soil using calcined oyster shells and waste cow bones.

    Science.gov (United States)

    Moon, Deok Hyun; Cheong, Kyung Hoon; Khim, Jeehyeong; Wazne, Mahmoud; Hyun, Seunghun; Park, Jeong-Hun; Chang, Yoon-Young; Ok, Yong Sik

    2013-05-01

    Pb(2+) and Cu(2+) contamination at army firing ranges poses serious environmental and health risks to nearby communities necessitating an immediate and prompt remedial action. In this study, a novel mixture of calcined oyster shells (COSs) and waste cow bones (WCBs) was utilized to immobilize Pb(2+) and Cu(2+) in army firing range soils. The effectiveness of the treatment was evaluated based on the Korean Standard leaching test. The treatment results showed that Pb(2+) and Cu(2+) immobilization in the army firing range soil was effective in significantly reducing Pb(2+) and Cu(2+) leachability upon the combined treatment with COS and WCB. A drastic reduction in Pb(2+) (99%) and Cu(2+) leachability (95%) was obtained as compared to the control sample, upon treatment with 5 wt.% COS and 5 wt.% WCB. The combination treatment of COS and WCB was more effective for Pb immobilization, than the treatment with COS or WCB alone. The 5 wt.% COS alone treatment resulted in 95% reduction in Cu(2+) leachability. The SEM-EDX results suggested that Pb(2+) and Cu(2+) immobilization was most probably associated with the formation of ettringite, pozzolanic reaction products and pyromorphite-like phases at the same time. Copyright © 2013 Elsevier Ltd. All rights reserved.

  12. Response of forest soil Acari to prescribed fire following stand structure manipulation in the southern Cascade Range.Can

    Science.gov (United States)

    Michael A. Camann; Nancy E. Gillette; Karen L. Lamoncha; Sylvia R. Mori

    2008-01-01

    We studied responses of Acari, especially oribatid mites, to prescribed low-intensity fire in an east side pine site in the southern Cascade Range in California. We compared oribatid population and assemblage responses to prescribed fire in stands that had been selectively logged to enhance old growth characteristics, in logged stands to minimize old growth...

  13. Soil Survey Geographic (SSURGO) database for White Sands Missile Range, New Mexico, Parts of Dona Ana, Lincoln, Otero, Sierra and Socorro Counties

    Data.gov (United States)

    Earth Data Analysis Center, University of New Mexico — This data set is a digital soil survey and generally is the most detailed level of soil geographic data developed by the National Cooperative Soil Survey. The...

  14. Wireless network of stand-alone end effect probes for soil in situ permittivity measurements over the 100MHZ-6GHz frequency range

    Science.gov (United States)

    Demontoux, François; Bircher, Simone; Ruffié, Gilles; Bonnaudiin, Fabrice; Wigneron, Jean-Pierre; Kerr, Yann

    2017-04-01

    Microwave remote sensing and non-destructive analysis are a powerful way to provide properties estimation of materials. Numerous applications using microwave frequency behavior of materials (remote sensing above land surfaces, non-destructive analysis…) are strongly dependent on the material's permittivity (i.e. dielectric properties). This permittivity depends on numerous parameters such as moisture, texture, temperature, frequency or bulk density. Permittivity measurements are generally carried out in the laboratory. Additionally, dielectric mixing models allow, over a restricted range of conditions, the assessment of a material's permittivity. in-situ measurements are more difficult to obtain. Some in situ measurement probes based on permittivity properties of soil exist (e.g. Time Domain Reflectometers and Transmissometers, capacitance and impedance sensors). They are dedicated to the acquisition of soil moisture data based on permittivity (mainly the real part) estimations over a range of frequencies from around 50 MHz to 1 or 2 GHz. Other Dielectric Assessment Kits exist but they are expensive and they are rather dedicated to laboratory measurements. Furthermore, the user can't address specific issues related to particular materials (e.g. organic soils) or specific measurement conditions (in situ long time records). At the IMS Laboratory we develop probes for in situ soil permittivity measurements (real and imaginary parts) in the 0.5 - 6 GHz frequency range. They are based on the end effect phenomenon of a coaxial waveguide and so are called end effect probes in this paper. The probes can be connected to a portable Vector Network Analyzer (VNA, ANRITSU MS2026A) for the S11 coefficient measurements needed to compute permittivity. It is connected to a PC to record data using an USB connection. This measurement set-up is already used for in situ measurement of soil properties in the framework of the European Space Agency's (ESA) SMOS space mission. However

  15. Soil physical properties affecting soil erosion in tropical soils

    International Nuclear Information System (INIS)

    Lobo Lujan, D.

    2004-01-01

    detachment. Studies on necessary kinetic energy to detach one kilogram of sediments by raindrop impact have shown that the minimum energy is required for particles of 0.125 mm. Particles between 0.063 to 0.250 mm are the most vulnerable to detachment. This means that soils with high content of particles into vulnerable range, for example silty loam, loamy, fine sandy, and sandy loam are the most susceptible soils to detachment. Many aspects of soil behaviour in the field such as hydraulic conductivity water retention, soil crusting, soil compaction, and workability are influenced strongly by the primary particles. In tropical soils also a negative relation between structure stability and particles of silt, fine sand and very fine sand has been found, this is attributed to low cohesiveness of these particles. The ability of a structure to persist is known as its stability. There are two principal types of stability: the ability of the soil to retain its structure under the action of water, and the ability of the soil to retain its structure under the action of external mechanical stresses. (e.g. by wheels). Both types of stability are related with susceptibility to erosion

  16. Multiscale principal component analysis

    International Nuclear Information System (INIS)

    Akinduko, A A; Gorban, A N

    2014-01-01

    Principal component analysis (PCA) is an important tool in exploring data. The conventional approach to PCA leads to a solution which favours the structures with large variances. This is sensitive to outliers and could obfuscate interesting underlying structures. One of the equivalent definitions of PCA is that it seeks the subspaces that maximize the sum of squared pairwise distances between data projections. This definition opens up more flexibility in the analysis of principal components which is useful in enhancing PCA. In this paper we introduce scales into PCA by maximizing only the sum of pairwise distances between projections for pairs of datapoints with distances within a chosen interval of values [l,u]. The resulting principal component decompositions in Multiscale PCA depend on point (l,u) on the plane and for each point we define projectors onto principal components. Cluster analysis of these projectors reveals the structures in the data at various scales. Each structure is described by the eigenvectors at the medoid point of the cluster which represent the structure. We also use the distortion of projections as a criterion for choosing an appropriate scale especially for data with outliers. This method was tested on both artificial distribution of data and real data. For data with multiscale structures, the method was able to reveal the different structures of the data and also to reduce the effect of outliers in the principal component analysis

  17. Main building complex WWER 440/213 upper range design response spectra for soft soil site conditions (Paks)

    International Nuclear Information System (INIS)

    Krutzik, N.

    1996-01-01

    Within the Benchmark studies parallel investigation were prepared for the main building complex of the WWER-440/213 Paks NPP by several participating institutions. The investigations were based on various mathematical models and procedures but all had the same seismological data as input. The calculation methods as well as software tools were different. This report covers the enveloped response results which were the basis for the benchmark studies and which should be used for upgrading of mechanical and electrical components and systems which will follow. These response spectra which consider a certain conservatism namely neglecting the frequency independence of the stiffness and the cut-off of damping values are named 'Upper Range design Benchmark Response Spectra' for the main building of Paks NPP

  18. Main building complex WWER 440/213 upper range design response spectra for soft soil site conditions (Paks)

    Energy Technology Data Exchange (ETDEWEB)

    Krutzik, N [Siemens AG, Power Generation Group (KWU) NDA2, Offenbach (Germany)

    1996-07-01

    Within the Benchmark studies parallel investigation were prepared for the main building complex of the WWER-440/213 Paks NPP by several participating institutions. The investigations were based on various mathematical models and procedures but all had the same seismological data as input. The calculation methods as well as software tools were different. This report covers the enveloped response results which were the basis for the benchmark studies and which should be used for upgrading of mechanical and electrical components and systems which will follow. These response spectra which consider a certain conservatism namely neglecting the frequency independence of the stiffness and the cut-off of damping values are named 'Upper Range design Benchmark Response Spectra' for the main building of Paks NPP.

  19. Principal noncommutative torus bundles

    DEFF Research Database (Denmark)

    Echterhoff, Siegfried; Nest, Ryszard; Oyono-Oyono, Herve

    2008-01-01

    of bivariant K-theory (denoted RKK-theory) due to Kasparov. Using earlier results of Echterhoff and Williams, we shall give a complete classification of principal non-commutative torus bundles up to equivariant Morita equivalence. We then study these bundles as topological fibrations (forgetting the group...

  20. The Principal as CEO

    Science.gov (United States)

    Hollar, Charlie

    2004-01-01

    They may never grace the pages of The Wall Street Journal or Fortune magazine, but they might possibly be the most important CEOs in our country. They are elementary school principals. Each of them typically serves the learning needs of 350-400 clients (students) while overseeing a multimillion-dollar facility staffed by 20-25 teachers and 10-15…

  1. Euler principal component analysis

    NARCIS (Netherlands)

    Liwicki, Stephan; Tzimiropoulos, Georgios; Zafeiriou, Stefanos; Pantic, Maja

    Principal Component Analysis (PCA) is perhaps the most prominent learning tool for dimensionality reduction in pattern recognition and computer vision. However, the ℓ 2-norm employed by standard PCA is not robust to outliers. In this paper, we propose a kernel PCA method for fast and robust PCA,

  2. Short-range spatial variability of soil δ15N natural abundance – effects on symbiotic N2-fixation estimates in pea

    DEFF Research Database (Denmark)

    Holdensen, Lars; Hauggaard-Nielsen, Henrik; Jensen, Erik Steen

    2007-01-01

    abundance in spring barley and N2-fixing pea was measured within the 0.15-4 m scale at flowering and at maturity. The short-range spatial variability of soil δ15N natural abundance and symbiotic nitrogen fixation were high at both growth stages. Along a 4-m row, the δ15N natural abundance in barley......-abundance are that estimates of symbiotic N2-fixation can be obtained from the natural abundance method if at least half a square meter of crop and reference plants is sampled for the isotopic analysis. In fields with small amounts of representative reference crops (weeds) it might be necessary to sow in reference crop...

  3. Study 3: Energy, alimentation and competition for soils use: problematic and safety principles; Etude 3: energie, alimentation et concurrence d'usage des sols: problematique et principes de prevention

    Energy Technology Data Exchange (ETDEWEB)

    Monot, C. [Solagral (France)

    2000-07-01

    For long-dated, the development of energies resulting from the biomass should aggravate the risks of soils use competition. On one hand the energy crops increase on fertile soils will limit the surfaces devoted to the alimentation and on the other hand intensive energy crops will risk to degrade the soils (erosion, pollution). The energy policies have to preserve from now onwards, the fossil energies resources, to limit the greenhouse effect and the nuclear wastes proliferation, but also to manage the soils resources to produce the bio-energies. This study tries to answer the following questions: Is there enough soils to produce the bio-energies in substitution to the fossil energies and food the humanity? Which is the policy that will participate to a good soils management, in order to preserve the alimentary potential? (A.L.B.)

  4. Visible Leading: Principal Academy Connects and Empowers Principals

    Science.gov (United States)

    Hindman, Jennifer; Rozzelle, Jan; Ball, Rachel; Fahey, John

    2015-01-01

    The School-University Research Network (SURN) Principal Academy at the College of William & Mary in Williamsburg, Virginia, has a mission to build a leadership development program that increases principals' instructional knowledge and develops mentor principals to sustain the program. The academy is designed to connect and empower principals…

  5. A survey of the occurrence of Bacillus anthracis in North American soils over two long-range transects and within post-Katrina New Orleans

    Science.gov (United States)

    Griffin, Dale W.; Petrosky, Terry; Morman, Suzette A.; Luna, Vicki A.

    2009-01-01

    Soil samples were collected along a north-south transect extending from Manitoba, Canada, to the US-Mexico border near El Paso, Texas in 2004 (104 samples), a group of sites within New Orleans, Louisiana following Hurricane Katrina in 2005 (19 samples), and a Gulf Coast transect extending from Sulphur, Louisiana, to DeFuniak Springs, Florida, in 2007 (38 samples). Samples were collected from the top 40 cm of soil and were screened for the presence of total Bacillus species and Bacillus anthracis (anthrax), specifically using multiplex-polymerase chain reaction (PCR). Using an assay with a sensitivity of ~170 equivalent colony-forming units (CFU) g-1 field moist soil, the prevalence rate of Bacillus sp./B. anthracis in the north-south transect and the 2005 New Orleans post-Katrina sample set were 20/5% and 26/26%, respectively. Prevalence in the 2007 Gulf Coast sample set using an assay with a sensitivity of ~4 CFU g-1 of soil was 63/0%. Individual transect-set data indicate a positive relation between occurrences of species and soil moisture or soil constituents (i.e., Zn and Cu content). The 2005 New Orleans post-Katrina data indicated that B. anthracis is readily detectable in Gulf Coast soils following flood events. The data also indicated that occurrence, as it relates to soil chemistry, may be confounded by flood-induced dissemination of germinated cells and the mixing of soil constituents for short temporal periods following an event.

  6. Seasonal and Daily Dynamics of the CO2 Emission from Soils of Pinus koraiensis Forests in the South of the Sikhote-Alin Range

    Science.gov (United States)

    Ivanov, A. V.; Braun, M.; Tataurov, V. A.

    2018-03-01

    The presented study shows the results of measuring soil respiration in typical burozems (Dystric Cambisols) under mixed Korean pine-broadleaved forests in the southern part of the Primorskii (Far East) region of Russia growing under conditions of monsoon climate. The measurements were performed in 2014-2016 by the chamber method with the use of a portable infrared gas analyzer. Relative and total values of the CO2 efflux from the soil surface on four model plots were determined. The intensity of summer emission varied from 2.25 to 10.97 μmol/(m2 s), and the total CO2 efflux from the soils of four plots varied from 18.84 to 25.56 mol/m2. It is shown that a larger part of seasonal variability in the soil respiration is controlled by the soil temperature ( R 2 = 0.5-0.7); the soil water content also has a significant influence on the CO2 emission determining about 10% of its temporal variability. The daily dynamics of soil respiration under the old-age (200 yrs) forest have a significant relationship with the soil temperature ( R 2 = 0.51). The pyrogenic transformation of Pinus koraiensis forests into low-value oak forests is accompanied by an increase in the CO2 efflux from the soil.

  7. The influence of fire history, plant species and post-fire management on soil water repellency in a Mediterranean catchment: the Mount Carmel range, Israel

    Science.gov (United States)

    Keesstra, Saskia; Wittenberg, Lea; Maroulis, Jerry; Malkinson, Dan; Cerdà, Artemi; Pereira, Paulo

    2016-04-01

    Fire is a key factor impacting soil hydrology in many Mediterranean catchments. Soil water repellency (SWR) can stimulate land degradation processes by reducing the affinity of soil and water thereby triggering a reduction in soil fertility and increasing soil and water losses (. The effects of two consequent fires (1989 and 2005) on SWR were assessed in the Carmel Mountains, Israel. Fire history, plant recovery and post-fire management were investigated as determining factors in a time dependent system. SWR was highest in the >50 years unburnt plots, where soil under Pinus halepensis is most hydrophobic. In the most disturbed soils (twice burnt), many sites have a low to absent SWR even if the soil is very dry. The dynamics and fluctuations in SWR differ in magnitude under different plant species. The areas treated with CC (chipping of charred trees) showed a much higher SWR than areas left untreated. From these insights, a conceptual model of the reaction of SWR on multiple fires was developed. KEYWORDS: Soil water repellency, WDPT, Wildfires, Vegetation recovery, post-fire management, Mediterranean.

  8. Radiological dose assessment for residual radioactive material in soil at the clean slate sites 1, 2, and 3, Tonopah Test Range

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-06-01

    A radiological dose assessment has been performed for Clean Slate Sites 1, 2, and 3 at the Tonopah Test Range, approximately 390 kilometers (240 miles) northwest of Las Vegas, Nevada. The assessment demonstrated that the calculated dose to hypothetical individuals who may reside or work on the Clean Slate sites, subsequent to remediation, does not exceed the limits established by the US Department of Energy for protection of members of the public and the environment. The sites became contaminated as a result of Project Roller Coaster experiments conducted in 1963 in support of the US Atomic Energy Commission (Shreve, 1964). Remediation of Clean Slate Sites 1, 2, and 3 is being performed to ensure that the 50-year committed effective dose equivalent to a hypothetical individual who lives or works on a Clean Slate site should not exceed 100 millirems per year. The DOE residual radioactive material guideline (RESRAD) computer code was used to assess the dose. RESRAD implements the methodology described in the DOE manual for establishing residual radioactive material guidelines (Yu et al., 1993a). In May and June of 1963, experiments were conducted at Clean Slate Sites 1, 2, and 3 to study the effectiveness of earth-covered structures for reducing the dispersion of nuclear weapons material as a result of nonnuclear explosions. The experiments required the detonation of various simulated weapons using conventional chemical explosives (Shreve, 1964). The residual radioactive contamination in the surface soil consists of weapons grade plutonium, depleted uranium, and their radioactive decay products.

  9. Traces of self-organisation and long-range memory in variations of environmental radon in soil. Comparative results from monitoring in Lesvos Island and Ileia (Greece)

    International Nuclear Information System (INIS)

    Dimitrios Nikolopoulos; Yiannis Chaldeos; Panayiotis Yannakopoulos; Sofia Kottou; Constantinos Nomicos

    2014-01-01

    This paper addresses issues of self-affinity, long-memory and self-organisation in variations of radon in soil recorded in Lesvos Island, Greece. Several techniques were employed, namely (a) power-law wavelet spectral fractal analysis, (b) estimation of Hurst exponents through (b1) rescaled-range, (b2) roughness-length, (b3) variogram and (a), (c) detrended fluctuation analysis, (d) investigation of fractal dimensions and (e) analysis of five block entropies: (e1) Shannon entropy, (e2) Shannon entropy per letter, (e3) conditional entropy, (e4) Tsallis entropy, and (e5) normalised Tsallis entropy. Long-lasting antipersistency was identified during a period of anomalous radon variations following fractional Brownian modelling. Remaining variations did not exhibit analogous behaviour and followed fractional Gaussian modelling. Antipersistent power-law-beta-exponent-values between 1.5 and 2.0 were detected during anomalies. Persistent values were also found. Hurst exponents were mainly within 0 (n) ≤ 0.59, conditional entropy, between 0.01 ≤ h (n) ≤ 0.58, Tsallis entropy, between 0.55 ≤ S q ≤ 1.01 and normalised Tsallis entropy between, 0.98 ≤ S ≤ 5.42 (block-size n = 4). Entropies were lower during anomalies, indicating strong self-organisation. Persistency–antipersistency switching was observed, consistent with long-memory dynamics. Potential geological sources were discussed. The asperity-model was proposed. Findings were compared to results obtained under analogous methodologies in Ileia, Greece. (author)

  10. Radiological dose assessment for residual radioactive material in soil at the clean slate sites 1, 2, and 3, Tonopah Test Range

    International Nuclear Information System (INIS)

    1997-06-01

    A radiological dose assessment has been performed for Clean Slate Sites 1, 2, and 3 at the Tonopah Test Range, approximately 390 kilometers (240 miles) northwest of Las Vegas, Nevada. The assessment demonstrated that the calculated dose to hypothetical individuals who may reside or work on the Clean Slate sites, subsequent to remediation, does not exceed the limits established by the US Department of Energy for protection of members of the public and the environment. The sites became contaminated as a result of Project Roller Coaster experiments conducted in 1963 in support of the US Atomic Energy Commission (Shreve, 1964). Remediation of Clean Slate Sites 1, 2, and 3 is being performed to ensure that the 50-year committed effective dose equivalent to a hypothetical individual who lives or works on a Clean Slate site should not exceed 100 millirems per year. The DOE residual radioactive material guideline (RESRAD) computer code was used to assess the dose. RESRAD implements the methodology described in the DOE manual for establishing residual radioactive material guidelines (Yu et al., 1993a). In May and June of 1963, experiments were conducted at Clean Slate Sites 1, 2, and 3 to study the effectiveness of earth-covered structures for reducing the dispersion of nuclear weapons material as a result of nonnuclear explosions. The experiments required the detonation of various simulated weapons using conventional chemical explosives (Shreve, 1964). The residual radioactive contamination in the surface soil consists of weapons grade plutonium, depleted uranium, and their radioactive decay products

  11. Influence of triethyl phosphate on phosphatase activity in shooting range soil: Isolation of a zinc-resistant bacterium with an acid phosphatase.

    Science.gov (United States)

    Story, Sandra; Brigmon, Robin L

    2017-03-01

    Phosphatase-mediated hydrolysis of organic phosphate may be a viable means of stabilizing heavy metals via precipitation as a metal phosphate in bioremediation applications. We investigated the effect of triethyl phosphate (TEP) on soil microbial-phosphatase activity in a heavy-metal contaminated soil. Gaseous TEP has been used at subsurface sites for bioremediation of organic contaminants but not applied in heavy-metal contaminated areas. Little is known about how TEP affects microbial activity in soils and it is postulated that TEP can serve as a phosphate source in nutrient-poor groundwater and soil/sediments. Over a 3-week period, TEP amendment to microcosms containing heavy-metal contaminated soil resulted in increased activity of soil acid-phosphatase and repression of alkaline phosphatase, indicating a stimulatory effect on the microbial population. A soil-free enrichment of microorganisms adapted to heavy-metal and acidic conditions was derived from the TEP-amended soil microcosms using TEP as the sole phosphate source and the selected microbial consortium maintained a high acid-phosphatase activity with repression of alkaline phosphatase. Addition of 5mM zinc to soil-free microcosms had little effect on acid phosphatase but inhibited alkaline phosphatase. One bacterial member from the consortium, identified as Burkholderia cepacia sp., expressed an acid-phosphatase activity uninhibited by high concentrations of zinc and produced a soluble, indigo pigment under phosphate limitation. The pigment was produced in a phosphate-free medium and was not produced in the presence of TEP or phosphate ion, indicative of purple acid-phosphatase types that are pressed by bioavailable phosphate. These results demonstrate that TEP amendment was bioavailable and increased overall phosphatase activity in both soil and soil-free microcosms supporting the possibility of positive outcomes in bioremediation applications. Copyright © 2016. Published by Elsevier Inc.

  12. Principals' Salaries, 2007-2008

    Science.gov (United States)

    Cooke, Willa D.; Licciardi, Chris

    2008-01-01

    How do salaries of elementary and middle school principals compare with those of other administrators and classroom teachers? Are increases in salaries of principals keeping pace with increases in salaries of classroom teachers? And how have principals' salaries fared over the years when the cost of living is taken into account? There are reliable…

  13. Principals Who Think Like Teachers

    Science.gov (United States)

    Fahey, Kevin

    2013-01-01

    Being a principal is a complex job, requiring quick, on-the-job learning. But many principals already have deep experience in a role at the very essence of the principalship. They know how to teach. In interviews with principals, Fahey and his colleagues learned that thinking like a teacher was key to their work. Part of thinking the way a teacher…

  14. School Principals' Emotional Coping Process

    Science.gov (United States)

    Poirel, Emmanuel; Yvon, Frédéric

    2014-01-01

    The present study examines the emotional coping of school principals in Quebec. Emotional coping was measured by stimulated recall; six principals were filmed during a working day and presented a week later with their video showing stressful encounters. The results show that school principals experience anger because of reproaches from staff…

  15. Legal Problems of the Principal.

    Science.gov (United States)

    Stern, Ralph D.; And Others

    The three talks included here treat aspects of the law--tort liability, student records, and the age of majority--as they relate to the principal. Specifically, the talk on torts deals with the consequences of principal negligence in the event of injuries to students. Assurance is given that a reasonable and prudent principal will have a minimum…

  16. RE Rooted in Principal's Biography

    NARCIS (Netherlands)

    ter Avest, Ina; Bakker, C.

    2017-01-01

    Critical incidents in the biography of principals appear to be steering in their innovative way of constructing InterReligious Education in their schools. In this contribution, the authors present the biographical narratives of 4 principals: 1 principal introducing interreligious education in a

  17. The Future of Principal Evaluation

    Science.gov (United States)

    Clifford, Matthew; Ross, Steven

    2012-01-01

    The need to improve the quality of principal evaluation systems is long overdue. Although states and districts generally require principal evaluations, research and experience tell that many state and district evaluations do not reflect current standards and practices for principals, and that evaluation is not systematically administered. When…

  18. Intervalo hídrico óptimo en suelos argiudoles plantados con Eucalyptus dunnii Maiden Least limiting water range in argiudoll soils under eucalyptus dunnii maiden

    Directory of Open Access Journals (Sweden)

    Francisco Damiano

    2011-07-01

    Full Text Available El Intervalo Hídrico Óptimo (IHO es el rango de agua del suelo dentro del cual el crecimiento de la planta está menos limitado por el potencial de agua, la aireación y la resistencia del suelo a la penetración de raíces. El IHO es a menudo determinado en cultivos, pero su aplicación en estudios de plantaciones forestales son escasos. Los objetivos fueron: a estimar el IHO del suelo en plantaciones de Eucalyptus dunnii joven y adulto usando funciones de edafo-transferencia; b relacionar funcionalmente la frecuencia de humedad observada localizada fuera del IHO (p fuera con el IHO y determinar si la relación es influenciada por el tipo de suelo y las condiciones meteorológicas del período de crecimiento. Se estimó el IHO en suelos Argiudoles Típico y Abrúptico, usando funciones de edafo-transferencia (FT de retención hídrica y resistencia del suelo. La frecuencia de humedad observada fuera del rango del IHO (p fuera fue evaluada estadísticamente usando el modelo PROC CATMOD. El IHO aumentó de 0,009 cm³ cm-³ (horizonte Bt arcillo limoso a 0,207 cm³ cm-3 (horizonte C franco limoso. El modelo de regresión logística muestra que pfuera se relacionó negativamente con el IHO (R² = 0,83***. La pendiente del modelo (b1 = -30,5475 no varió por condiciones climáticas pero la ordenada al origen resultó influenciada por este parámetro (b o seco = 5,0083; b o húmedo = 3,5207. El modelo fundamental-empírico sostuvo al IHO como un indicador de calidad física del suelo apto para evaluar factores climáticos que inciden sobre el consumo de agua en eucaliptos.The Least Limiting Water Range (LLWR integrates water potential, aeration and mechanical resistance conditions that can be limiting to plant growth. The LLWR was often determined in field crops, but studies performed under tree plantations are scarce. In this study, soil LLWR was determined in young and mature Eucalyptus dunnii plantations using pedo-transfer functions. Frequency

  19. Principal stratification in causal inference.

    Science.gov (United States)

    Frangakis, Constantine E; Rubin, Donald B

    2002-03-01

    Many scientific problems require that treatment comparisons be adjusted for posttreatment variables, but the estimands underlying standard methods are not causal effects. To address this deficiency, we propose a general framework for comparing treatments adjusting for posttreatment variables that yields principal effects based on principal stratification. Principal stratification with respect to a posttreatment variable is a cross-classification of subjects defined by the joint potential values of that posttreatment variable tinder each of the treatments being compared. Principal effects are causal effects within a principal stratum. The key property of principal strata is that they are not affected by treatment assignment and therefore can be used just as any pretreatment covariate. such as age category. As a result, the central property of our principal effects is that they are always causal effects and do not suffer from the complications of standard posttreatment-adjusted estimands. We discuss briefly that such principal causal effects are the link between three recent applications with adjustment for posttreatment variables: (i) treatment noncompliance, (ii) missing outcomes (dropout) following treatment noncompliance. and (iii) censoring by death. We then attack the problem of surrogate or biomarker endpoints, where we show, using principal causal effects, that all current definitions of surrogacy, even when perfectly true, do not generally have the desired interpretation as causal effects of treatment on outcome. We go on to forrmulate estimands based on principal stratification and principal causal effects and show their superiority.

  20. Le principe roman

    CERN Document Server

    Ferrari, Jérôme

    2015-01-01

    Fasciné par la figure du physicien allemand Werner Heisenberg (1901-1976), fondateur de la mécanique quantique, inventeur du célèbre "principe d'incertitude" et Prix Nobel de physique en 1932, un jeune aspirant-philosophe désenchanté s'efforce, à l'aube du XXIe siècle, de considérer l'incomplétude de sa propre existence à l'aune des travaux et de la destinée de cet exceptionnel homme de sciences qui incarne pour lui la rencontre du langage scientifique et de la poésie, lesquels, chacun à leur manière, en ouvrant la voie au scandale de l'inédit, dessillent les yeux sur le monde pour en révéler la mystérieuse beauté que ne cessent de confisquer le matérialisme à l'œuvre dans l'Histoire des hommes.

  1. Principal oscillation patterns

    International Nuclear Information System (INIS)

    Storch, H. von; Buerger, G.; Storch, J.S. von

    1993-01-01

    The Principal Oscillation Pattern (POP) analysis is a technique which is used to simultaneously infer the characteristic patterns and time scales of a vector time series. The POPs may be seen as the normal modes of a linearized system whose system matrix is estimated from data. The concept of POP analysis is reviewed. Examples are used to illustrate the potential of the POP technique. The best defined POPs of tropospheric day-to-day variability coincide with the most unstable modes derived from linearized theory. POPs can be derived even from a space-time subset of data. POPs are successful in identifying two independent modes with similar time scales in the same data set. The POP method can also produce forecasts which may potentially be used as a reference for other forecast models. The conventional POP analysis technique has been generalized in various ways. In the cyclostationary POP analysis, the estimated system matrix is allowed to vary deterministically with an externally forced cycle. In the complex POP analysis not only the state of the system but also its ''momentum'' is modeled. Associated correlation patterns are a useful tool to describe the appearance of a signal previously identified by a POP analysis in other parameters. (orig.)

  2. Proceedings of the International Symposium on Frozen Soil Impacts on Agricultural, Range, and Forest Lands Held at Spokane, Washington on March 21-22, 1990

    Science.gov (United States)

    1990-03-01

    the United States. The soils were: a Cecil sandy loam (clayey, kaolinitic, thermic Typic Hapludult) from Watkinsville, GA ; a Barnes loam (fine loamy...1987). GLEAMS user manual. Lab Note South East Watershed Research Laboratory 110 187 WGK, Tifton , Ge, 1987. Lane, L.J., and V. A. Ferreira, (1980...as caps for processed uranium mill tailings in the western United States. The purpose of these barriers is to control radon gas release. The soil

  3. Análise de componentes principais de atributos físicos, químicos e mineralógicos de solos do bioma cerrado Principal component analysis of physical, chemical, and mineralogical attributes of the cerrado biome soils

    Directory of Open Access Journals (Sweden)

    J. B. V. Gomes

    2004-02-01

    evaluated by physical, chemical, and mineralogical characterizations, and principal component analyses. According to their sub-region and geomorphic surfaces, the soils were separated in three groups: 1. clayey to very clayey texture, low- and mesoferric; 2. medium to sandy texture, lowferric; 3. clayey to very clayey texture, ferric. Water retention in the surface horizons of the studied soils was positively correlated with the clay and organic carbon contents. Soils of Group 3 showed the greatest amount of exchangeable bases in the surface horizons, which is mainly a consequence of the greater recycling efficiency imposed by the local forest formation when compared to the Cerrado formation (verified in 31 of the 33 soil profiles of Groups 1 and 2. Soils of Group 3, formed from mafic rocks, were the most homogeneous in mineralogical terms, since all profiles were hematitic. In averages, Groups 1 and 2 presented an overlapping mineralogical composition, though Group 1 is more gibbsitic than Group 2. In comparison to the US Soil Taxonomy, the efficacy of the Brazilian Soil Classification System at discriminating the studied soils is higher owing to the use of the ferric character in conjunction with the other attributes both systems have in common. The principal component analysis supported the understanding of the pedologic environment differences and similarities identified in the field.

  4. Portraits of Principal Practice: Time Allocation and School Principal Work

    Science.gov (United States)

    Sebastian, James; Camburn, Eric M.; Spillane, James P.

    2018-01-01

    Purpose: The purpose of this study was to examine how school principals in urban settings distributed their time working on critical school functions. We also examined who principals worked with and how their time allocation patterns varied by school contextual characteristics. Research Method/Approach: The study was conducted in an urban school…

  5. The ingestion of plutonium and americium by range cattle

    International Nuclear Information System (INIS)

    Blincoe, C.; Bohman, V.R.; Smith, D.D.

    1981-01-01

    The intake of plutonium and americium in the diet of cattle grazing on plutonium contaminated desert range was determined. Daily feed intake of the grazing animals was also determined so that the amount of nuclides ingested daily could be ascertained. Soil ingested by range cattle constituted the principal and possibly only source of ingested plutonium and americium and resulted in a daily intake of 3600-6600 pCi 238 Pu, 85,000-400,000 pCi 239 Pu, and 11,000-31,000 pCi 241 Am daily. Determining transuranic intake by direct measurement and from the composition and contamination of the diet gave identical results. (author)

  6. Principal spectra describing magnetooptic permittivity tensor in cubic crystals

    Energy Technology Data Exchange (ETDEWEB)

    Hamrlová, Jana [Nanotechnology Centre, VSB – Technical University of Ostrava, listopadu 15, Ostrava, 708 33 Czech Republic (Czech Republic); IT4Innovations Centre, VSB – Technical University of Ostrava, listopadu 15, Ostrava, 708 33 Czech Republic (Czech Republic); Legut, Dominik [IT4Innovations Centre, VSB – Technical University of Ostrava, listopadu 15, Ostrava, 708 33 Czech Republic (Czech Republic); Veis, Martin [Faculty of Mathematics and Physics, Charles University, Ke Karlovu 3, Prague, 121 16 Czech Republic (Czech Republic); Pištora, Jaromír [Nanotechnology Centre, VSB – Technical University of Ostrava, listopadu 15, Ostrava, 708 33 Czech Republic (Czech Republic); Hamrle, Jaroslav, E-mail: jaroslav.hamrle@vsb.cz [IT4Innovations Centre, VSB – Technical University of Ostrava, listopadu 15, Ostrava, 708 33 Czech Republic (Czech Republic); Faculty of Mathematics and Physics, Charles University, Ke Karlovu 3, Prague, 121 16 Czech Republic (Czech Republic); Department of Physics, VSB – Technical University of Ostrava, 17. listopadu 15, Ostrava, 708 33 Czech Republic (Czech Republic)

    2016-12-15

    We provide unified phenomenological description of magnetooptic effects being linear and quadratic in magnetization. The description is based on few principal spectra, describing elements of permittivity tensor up to the second order in magnetization. Each permittivity tensor element for any magnetization direction and any sample surface orientation is simply determined by weighted summation of the principal spectra, where weights are given by crystallographic and magnetization orientations. The number of principal spectra depends on the symmetry of the crystal. In cubic crystals owning point symmetry we need only four principal spectra. Here, the principal spectra are expressed by ab initio calculations for bcc Fe, fcc Co and fcc Ni in optical range as well as in hard and soft x-ray energy range, i.e. at the 2p- and 3p-edges. We also express principal spectra analytically using modified Kubo formula.

  7. Monitoring Soil Erosion of a Burn Site in the Central Basin and Range Ecoregion: Final Report on Measurements at the Gleason Fire Site, Nevada

    Energy Technology Data Exchange (ETDEWEB)

    Miller, Julianne [DRI; Etyemezian, Vicken [DRI; Shillito, Rose [DRI; Cablk, Mary [DRI; Fenstermaker, Lynn [DRI; Shafer, David [DOE Legacy Management

    2013-10-01

    The increase in wildfires in arid and semi-arid parts of Nevada and elsewhere in the southwestern United States has implications for post-closure management and long-term stewardship for Soil Corrective Action Units (CAUs) on the Nevada National Security Site (NNSS) for which the Nevada Field Office of the United States Department of Energy, National Nuclear Security Administration has responsibility. For many CAUs and Corrective Action Sites, where closure-in-place alternatives are now being implemented or considered, there is a chance that these sites could burn over at some time while they still pose a risk to the environment or human health, given the long half lives of some of the radionuclide contaminants. This study was initiated to examine the effects and duration of wildfire on wind and water erodibility on sites analogous to those that exist on the NNSS. The data analyzed herein were gathered at the prescribed Gleason Fire site near Ely, Nevada, a site comparable to the northern portion of the NNSS. Quantification of wind erosion was conducted with a Portable In-Situ Wind ERosion Lab (PI-SWERL) on unburned soils, and on interspace and plant understory soils within the burned area. The PI-SWERL was used to estimate emissions of suspendible particles (particulate matter with aerodynamic diameters less than or equal to 10 micrometers) at different wind speeds. Filter samples, collected from the exhaust of the PI-SWERL during measurements, were analyzed for chemical composition. Based on nearly three years of data, the Gleason Fire site does not appear to have returned to pre burn wind erosion levels. Chemical composition data of suspendible particles are variable and show a trend toward pre-burn levels, but provide little insight into how the composition has been changing over time since the fire. Soil, runoff, and sediment data were collected from the Gleason Fire site to monitor the water erosion potential over the nearly three-year period. Soil

  8. Assessment of heavy metals in soils of a vineyard region with the use of principal component analysis Avaliação de metais pesados em solos de região de vinhedos com o uso da análise dos componentes principais

    Directory of Open Access Journals (Sweden)

    Gustavo Souza Valladares

    2009-06-01

    Full Text Available Agricultural management with chemicals may contaminate the soil with heavy metals. The objective of this study was to apply Principal Component Analysis and geoprocessing techniques to identify the origin of the metals Cu, Fe, Mn, Zn, Ni, Pb, Cr and Cd as potential contaminants of agricultural soils. The study was developed in an area of vineyard cultivation in the State of São Paulo, Brazil. Soil samples were collected and GPS located under different uses and coverings. The metal concentrations in the soils were determined using the DTPA method. The Cu and Zn content was considered high in most of the samples, and was larger in the areas cultivated with vineyards that had been under the application of fungicides for several decades. The concentrations of Cu and Zn were correlated. The geoprocessing techniques and the Principal Component Analysis confirmed the enrichment of the soil with Cu and Zn because of the use and management of the vineyards with chemicals in the preceding decades.O manejo agrícola com agroquímicos pode levar a contaminação dos solos por metais pesados. O objetivo deste trabalho foi aplicar a Análise dos Componentes Principais e técnicas de geoprocessamento para identificar a origem dos metais pesados Cu, Fe, Mn, Zn, Ni, Pb, Cr e Cd como contaminantes potenciais em solos agrícolas. O estudo foi desenvolvido em uma área cultivada com vinhedos no Estado de São Paulo, Brazil. Amostras de solos foram coletadas e georeferenciadas por GPS sob diferentes usos e coberturas. As concentrações dos metais nos solos foram obtidas pelo método de extração com DTPA. As concentrações de Cu e Zn foram consideradas altas na maioria das amostras pesquisadas, sendo maiores nas áreas cultivadas com vinhedos sob aplicações de fungicidas por décadas. As concentrações de Cu e Zn apresentaram correlação. As técnicas de geoprocessamento e a Análise dos Componentes Principais indicaram enriquecimento do solo com Cu e Zn

  9. School Principals' Sources of Knowledge

    Science.gov (United States)

    Perkins, Arland Early

    2014-01-01

    The purpose of this study was to determine what sources of professional knowledge are available to principals in 1 rural East Tennessee school district. Qualitative research methods were applied to gain an understanding of what sources of knowledge are used by school principals in 1 rural East Tennessee school district and the barriers they face…

  10. Innovation Management Perceptions of Principals

    Science.gov (United States)

    Bakir, Asli Agiroglu

    2016-01-01

    This study is aimed to determine the perceptions of principals about innovation management and to investigate whether there is a significant difference in this perception according to various parameters. In the study, descriptive research model is used and universe is consisted from principals who participated in "Acquiring Formation Course…

  11. What Do Effective Principals Do?

    Science.gov (United States)

    Protheroe, Nancy

    2011-01-01

    Much has been written during the past decade about the changing role of the principal and the shift in emphasis from manager to instructional leader. Anyone in education, and especially principals themselves, could develop a mental list of responsibilities that fit within each of these realms. But research makes it clear that both those aspects of…

  12. Time Management for New Principals

    Science.gov (United States)

    Ruder, Robert

    2008-01-01

    Becoming a principal is a milestone in an educator's professional life. The principalship is an opportunity to provide leadership that will afford students opportunities to thrive in a nurturing and supportive environment. Despite the continuously expanding demands of being a new principal, effective time management will enable an individual to be…

  13. Bureaucratic Control and Principal Role.

    Science.gov (United States)

    Bezdek, Robert; And Others

    The purposes of this study were to determine the manner in which the imposition of increased bureaucratic control over principals influenced their allocation of time to tasks and to investigate principals' perceptions of the changes in their roles brought about by this increased control. The specific bureaucratic control system whose effects were…

  14. Evapotranspiration and soil water relationships in a range of disturbed and undisturbed ecosystems in the semi-arid Inner Mongolia, China

    Science.gov (United States)

    Nan Lu; Shiping Chen; Burkhard Wilske; Ge Sun; Jiquan Chen

    2011-01-01

    Aims: Evapotranspiration (ET) is a key component of water balance and is closely linked to ecosystem productivity. In arid regions, large proportion of precipitation (PPT) is returned to the atmosphere through ET, with only a small amount available to plants. Our objective was to examine the variability in ET–soil water relationship based on a set of ecosystems that...

  15. Microbiome and ecotypic adaption of Holcus lanatus (L.) to extremes of its soil pH range, investigated through transcriptome sequencing.

    Science.gov (United States)

    Young, Ellen; Carey, Manus; Meharg, Andrew A; Meharg, Caroline

    2018-03-20

    Plants can adapt to edaphic stress, such as nutrient deficiency, toxicity and biotic challenges, by controlled transcriptomic responses, including microbiome interactions. Traditionally studied in model plant species with controlled microbiota inoculation treatments, molecular plant-microbiome interactions can be functionally investigated via RNA-Seq. Complex, natural plant-microbiome studies are limited, typically focusing on microbial rRNA and omitting functional microbiome investigations, presenting a fundamental knowledge gap. Here, root and shoot meta-transcriptome analyses, in tandem with shoot elemental content and root staining, were employed to investigate transcriptome responses in the wild grass Holcus lanatus and its associated natural multi-species eukaryotic microbiome. A full factorial reciprocal soil transplant experiment was employed, using plant ecotypes from two widely contrasting natural habitats, acid bog and limestone quarry soil, to investigate naturally occurring, and ecologically meaningful, edaphically driven molecular plant-microbiome interactions. Arbuscular mycorrhizal (AM) and non-AM fungal colonization was detected in roots in both soils. Staining showed greater levels of non-AM fungi, and transcriptomics indicated a predominance of Ascomycota-annotated genes. Roots in acid bog soil were dominated by Phialocephala-annotated transcripts, a putative growth-promoting endophyte, potentially involved in N nutrition and ion homeostasis. Limestone roots in acid bog soil had greater expression of other Ascomycete genera and Oomycetes and lower expression of Phialocephala-annotated transcripts compared to acid ecotype roots, which corresponded with reduced induction of pathogen defense processes, particularly lignin biosynthesis in limestone ecotypes. Ascomycota dominated in shoots and limestone soil roots, but Phialocephala-annotated transcripts were insignificant, and no single Ascomycete genus dominated. Fusarium-annotated transcripts were

  16. The Principal's Role in Site-Based Management.

    Science.gov (United States)

    Drury, William R.

    1993-01-01

    In existing school-based management models, the principal's role ranges from chairing the local council to being a coach/facilitator. With teachers and parents assuming greater control over governance, curriculum, and budgeting, paranoid principals may establish more formal bargaining relationships with district boards. Caution is advised, because…

  17. relationship between principals' management approaches

    African Journals Online (AJOL)

    Admin

    Data were collected using a self-administered questionnaire from a sample of. 211 teachers, 28 principals and 22 chairpersons of parent- teachers association. Data were ..... their role expectation in discipline management. Data from the 20 ...

  18. Principals, agents and research programmes

    OpenAIRE

    Elizabeth Shove

    2003-01-01

    Research programmes appear to represent one of the more powerful instruments through which research funders (principals) steer and shape what researchers (agents) do. The fact that agents navigate between different sources and styles of programme funding and that they use programmes to their own ends is readily accommodated within principal-agent theory with the help of concepts such as shirking and defection. Taking a different route, I use three examples of research programming (by the UK, ...

  19. Geochemical Background and Baseline Values Determination and Spatial Distribution of Heavy Metal Pollution in Soils of the Andes Mountain Range (Cajamarca-Huancavelica, Peru)

    Science.gov (United States)

    Santos-Francés, Fernando; Alonso Rojo, Pilar; García Sánchez, Antonio

    2017-01-01

    Concentrations of seven heavy metals (Cd, Cr, Cu, Hg, Ni, Pb, and Zn) and one metalloid (As) as well as various parameters (pH, organic carbon, granulometric analysis and cation exchange capacity) were analyzed in 77 soil samples collected in the mining areas of La Zanja and Colquirrumi (Department of Cajamarca) and Julcani (Department of Huancavelica). Our study proposed geochemical baseline values for heavy metals in a natural region (La Zanja) from samples collected during the period of the environmental impact study (2006), that is, from an earlier period which occurred at the beginning of the exploitation of the current gold mine. The baseline values obtained were as follows: 8.26 mg·kg−1 for Cr; 56.97 mg·kg−1 for Ni; 22, 20 mg·kg−1 for the Cu; 47.42 mg·kg−1 for Zn; 27.50 mg·kg−1 for As; 4.36 mg·kg−1 for Cd; 4.89 mg·kg−1 for Hg, and 44.87 mg·kg−1 for Pb. Through the use of different indices of heavy metal contamination (geo-accumulation index (Igeo), improved Nemerow index (IIN) and potential ecological risk index (RI)), the degree of pollution caused by mining activities in two areas, Colquirrumi and Julcani, which have a high density of mining sites in operation, was determined. The values obtained from these indices indicated that the Colquirrumi region was the most contaminated, followed by Julcani. The area of La Zanja, despite being free of mining operations, presented slight diffuse pollution. Several positive correlations were obtained, with a high level of significance, between pH, organic carbon content, cation exchange capacity, and the Cr, Pb and Ni concentrations of the soils. The spatial distribution of the heavy metals was realized by means of the interpolation method of ordinary kriging. The results obtained and the experience gained in this work were necessary to facilitate the identification of soil contamination processes in high altitude areas of the Andes Western Cordillera (Peru) as a basis for taking appropriate

  20. Geochemical Background and Baseline Values Determination and Spatial Distribution of Heavy Metal Pollution in Soils of the Andes Mountain Range (Cajamarca-Huancavelica, Peru).

    Science.gov (United States)

    Santos-Francés, Fernando; Martinez-Graña, Antonio; Alonso Rojo, Pilar; García Sánchez, Antonio

    2017-07-31

    Concentrations of seven heavy metals (Cd, Cr, Cu, Hg, Ni, Pb, and Zn) and one metalloid (As) as well as various parameters (pH, organic carbon, granulometric analysis and cation exchange capacity) were analyzed in 77 soil samples collected in the mining areas of La Zanja and Colquirrumi (Department of Cajamarca) and Julcani (Department of Huancavelica). Our study proposed geochemical baseline values for heavy metals in a natural region (La Zanja) from samples collected during the period of the environmental impact study (2006), that is, from an earlier period which occurred at the beginning of the exploitation of the current gold mine. The baseline values obtained were as follows: 8.26 mg kg-1 for Cr; 56.97 mg kg-1 for Ni; 22, 20 mg kg-1 for the Cu; 47.42 mg kg-1 for Zn; 27.50 mg kg-1 for As; 4.36 mg kg-1 for Cd; 4.89 mg kg-1 for Hg, and 44.87 mg kg-1 for Pb. Through the use of different indices of heavy metal contamination (geo-accumulation index (Igeo), improved Nemerow index (IIN) and potential ecological risk index (RI)), the degree of pollution caused by mining activities in two areas, Colquirrumi and Julcani, which have a high density of mining sites in operation, was determined. The values obtained from these indices indicated that the Colquirrumi region was the most contaminated, followed by Julcani. The area of La Zanja, despite being free of mining operations, presented slight diffuse pollution. Several positive correlations were obtained, with a high level of significance, between pH, organic carbon content, cation exchange capacity, and the Cr, Pb and Ni concentrations of the soils. The spatial distribution of the heavy metals was realized by means of the interpolation method of ordinary kriging. The results obtained and the experience gained in this work were necessary to facilitate the identification of soil contamination processes in high altitude areas of the Andes Western Cordillera (Peru) as a basis for taking appropriate measures when restoring

  1. An investigation of inorganic antimony species and antimony associated with soil humic acid molar mass fractions in contaminated soils

    International Nuclear Information System (INIS)

    Steely, Sarah; Amarasiriwardena, Dulasiri; Xing Baoshan

    2007-01-01

    The presence of antimony compounds is often suspected in the soil of apple orchards contaminated with lead arsenate pesticide and in the soil of shooting ranges. Nitric acid (1 M) extractable Sb from the shooting range (8300 μg kg -1 ) and the apple orchard (69 μg kg -1 ) had considerably higher surface Sb levels than the control site ( -1 ), and Sb was confined to the top ∼30 cm soil layer. Sb(V) was the principal species in the shooting range and the apple orchard surface soils. Size exclusion chromatography-inductively coupled plasma-mass spectrometry (SEC-ICP-MS) analysis of humic acids isolated from the two contaminated soils demonstrated that Sb has complexed to humic acid molar mass fractions. The results also indicate that humic acids have the ability to arrest the mobility of Sb through soils and would be beneficial in converting Sb(III) to a less toxic species, Sb(V), in contaminated areas. - The soil surface and depth distribution Sb(V) and Sb(III) species in a contaminated apple orchard and a shooting range, and the effect soil humic acids on inorganic antimony species is reported

  2. Recently deglaciated high-altitude soils of the Himalaya: diverse environments, heterogenous bacterial communities and long-range dust inputs from the upper troposphere.

    Directory of Open Access Journals (Sweden)

    Blaz Stres

    Full Text Available The Himalaya with its altitude and geographical position forms a barrier to atmospheric transport, which produces much aqueous-particle monsoon precipitation and makes it the largest continuous ice-covered area outside polar regions. There is a paucity of data on high-altitude microbial communities, their native environments and responses to environmental-spatial variables relative to seasonal and deglaciation events.Soils were sampled along altitude transects from 5000 m to 6000 m to determine environmental, spatial and seasonal factors structuring bacterial communities characterized by 16 S rRNA gene deep sequencing. Dust traps and fresh-snow samples were used to assess dust abundance and viability, community structure and abundance of dust associated microbial communities. Significantly different habitats among the altitude-transect samples corresponded to both phylogenetically distant and closely-related communities at distances as short as 50 m showing high community spatial divergence. High within-group variability that was related to an order of magnitude higher dust deposition obscured seasonal and temporal rearrangements in microbial communities. Although dust particle and associated cell deposition rates were highly correlated, seasonal dust communities of bacteria were distinct and differed significantly from recipient soil communities. Analysis of closest relatives to dust OTUs, HYSPLIT back-calculation of airmass trajectories and small dust particle size (4-12 µm suggested that the deposited dust and microbes came from distant continental, lacustrine and marine sources, e.g. Sahara, India, Caspian Sea and Tibetan plateau. Cyanobacteria represented less than 0.5% of microbial communities suggesting that the microbial communities benefitted from (codeposited carbon which was reflected in the psychrotolerant nature of dust-particle associated bacteria.The spatial, environmental and temporal complexity of the high-altitude soils of the

  3. Recently deglaciated high-altitude soils of the Himalaya: diverse environments, heterogenous bacterial communities and long-range dust inputs from the upper troposphere.

    Science.gov (United States)

    Stres, Blaz; Sul, Woo Jun; Murovec, Bostjan; Tiedje, James M

    2013-01-01

    The Himalaya with its altitude and geographical position forms a barrier to atmospheric transport, which produces much aqueous-particle monsoon precipitation and makes it the largest continuous ice-covered area outside polar regions. There is a paucity of data on high-altitude microbial communities, their native environments and responses to environmental-spatial variables relative to seasonal and deglaciation events. Soils were sampled along altitude transects from 5000 m to 6000 m to determine environmental, spatial and seasonal factors structuring bacterial communities characterized by 16 S rRNA gene deep sequencing. Dust traps and fresh-snow samples were used to assess dust abundance and viability, community structure and abundance of dust associated microbial communities. Significantly different habitats among the altitude-transect samples corresponded to both phylogenetically distant and closely-related communities at distances as short as 50 m showing high community spatial divergence. High within-group variability that was related to an order of magnitude higher dust deposition obscured seasonal and temporal rearrangements in microbial communities. Although dust particle and associated cell deposition rates were highly correlated, seasonal dust communities of bacteria were distinct and differed significantly from recipient soil communities. Analysis of closest relatives to dust OTUs, HYSPLIT back-calculation of airmass trajectories and small dust particle size (4-12 µm) suggested that the deposited dust and microbes came from distant continental, lacustrine and marine sources, e.g. Sahara, India, Caspian Sea and Tibetan plateau. Cyanobacteria represented less than 0.5% of microbial communities suggesting that the microbial communities benefitted from (co)deposited carbon which was reflected in the psychrotolerant nature of dust-particle associated bacteria. The spatial, environmental and temporal complexity of the high-altitude soils of the Himalaya

  4. Warming and the dependence of limber pine (Pinus flexilis) establishment on summer soil moisture within and above its current elevation range

    Science.gov (United States)

    Moyes, Andrew B.; Castanha, Cristina; Germino, Matthew J.; Kueppers, Lara M.

    2013-01-01

    Continued changes in climate are projected to alter the geographic distributions of plant species, in part by affecting where individuals can establish from seed. We tested the hypothesis that warming promotes uphill redistribution of subalpine tree populations by reducing cold limitation at high elevation and enhancing drought stress at low elevation. We seeded limber pine (Pinus flexilis) into plots with combinations of infrared heating and water addition treatments, at sites positioned in lower subalpine forest, the treeline ecotone, and alpine tundra. In 2010, first-year seedlings were assessed for physiological performance and survival over the snow-free growing season. Seedlings emerged in midsummer, about 5–8 weeks after snowmelt. Low temperature was not observed to limit seedling photosynthesis or respiration between emergence and October, and thus experimental warming did not appear to reduce cold limitation at high elevation. Instead, gas exchange and water potential from all sites indicated a prevailing effect of summer moisture stress on photosynthesis and carbon balance. Infrared heaters raised soil growing degree days (base 5 °C, p p 3 m-3 consistently corresponded with moderate and severe indications of drought stress in midday stem water potential, stomatal conductance, photosynthesis, and respiration. Seedling survival was greater in watered plots than in heated plots (p = 0.01), and negatively related to soil growing degree days and duration of exposure to θ 3 m-3 in a stepwise linear regression model (p seasonal moisture stress and high soil surface temperature imposed a strong limitation to limber pine seedling establishment across a broad elevation gradient, including at treeline, and that these limitations are likely to be enhanced by further climate warming.

  5. Proper Particle Size Range for Resistance to Chemical Oxidation: A Perspective on the Recalcitrance of Beanpod Biochar for Soil Carbon Sequestration

    Institute of Scientific and Technical Information of China (English)

    Jianhua GUO; Dongyun ZHANG

    2017-01-01

    The effect of particle size on the recalcitrance of biochar against oxidation has been regarded as one of the most important factors influencing its stability and transportation in soils. Little is known about the peculiar stability of different particle sizes under chemical oxidation conditions. In this study, several sizes of biochar particles derived from beanpod were produced,and their stabilities were tested by using acid dichromate and hydrogen peroxide. We discovered that the 60-100 mesh size of particles produced at 400 and 500 ℃ showed the least carbon loss under the oxidation of both dichromate and hydrogen peroxide.In addition, this particle size also shows great stability at 600 and 700 ℃, but this stability was not observed below 300 °C for all temperature-dependent biochars. Medium-sized particles composed of exclusively heterogeneous components produced a biochar at temperatures over 400 ℃ with comparatively stronger chemical anti-oxidation characteristics. The chemical recalcitrance of biochar should be reevaluated based on particle size before soil application.

  6. Principal Curves on Riemannian Manifolds.

    Science.gov (United States)

    Hauberg, Soren

    2016-09-01

    Euclidean statistics are often generalized to Riemannian manifolds by replacing straight-line interpolations with geodesic ones. While these Riemannian models are familiar-looking, they are restricted by the inflexibility of geodesics, and they rely on constructions which are optimal only in Euclidean domains. We consider extensions of Principal Component Analysis (PCA) to Riemannian manifolds. Classic Riemannian approaches seek a geodesic curve passing through the mean that optimizes a criteria of interest. The requirements that the solution both is geodesic and must pass through the mean tend to imply that the methods only work well when the manifold is mostly flat within the support of the generating distribution. We argue that instead of generalizing linear Euclidean models, it is more fruitful to generalize non-linear Euclidean models. Specifically, we extend the classic Principal Curves from Hastie & Stuetzle to data residing on a complete Riemannian manifold. We show that for elliptical distributions in the tangent of spaces of constant curvature, the standard principal geodesic is a principal curve. The proposed model is simple to compute and avoids many of the pitfalls of traditional geodesic approaches. We empirically demonstrate the effectiveness of the Riemannian principal curves on several manifolds and datasets.

  7. Micrometeorological, evapotranspiration, and soil-moisture data at the Amargosa Desert Research site in Nye County near Beatty, Nevada, 2006-11

    Science.gov (United States)

    Arthur, Jonathan M.; Johnson, Michael J.; Mayers, C. Justin; Andraski, Brian J.

    2012-01-01

    This report describes micrometeorological, evapotranspiration, and soil-moisture data collected since 2006 at the Amargosa Desert Research Site adjacent to a low-level radio-active waste and hazardous chemical waste facility near Beatty, Nevada. Micrometeorological data include precipitation, solar radiation, net radiation, air temperature, relative humidity, saturated and ambient vapor pressure, wind speed and direction, barometric pressure, near-surface soil temperature, soil-heat flux, and soil-water content. Evapotranspiration (ET) data include latent-heat flux, sensible-heat flux, net radiation, soil-heat flux, soil temperature, air temperature, vapor pressure, and other principal energy-budget data. Soil-moisture data include periodic measurements of volumetric water-content at experimental sites that represent vegetated native soil, devegetated native soil, and simulated waste disposal trenches - maximum measurement depths range from 5.25 to 29.25 meters. All data are compiled in electronic spreadsheets that are included with this report.

  8. The Principal and the Law. Elementary Principal Series No. 7.

    Science.gov (United States)

    Doverspike, David E.; Cone, W. Henry

    Developments over the past 25 years in school-related legal issues in elementary schools have significantly changed the principal's role. In 1975, a decision of the U.S. Supreme Court established three due-process guidelines for short-term suspension. The decision requires student notification of charges, explanation of evidence, and an informal…

  9. Surface analysis the principal techniques

    CERN Document Server

    Vickerman, John C

    2009-01-01

    This completely updated and revised second edition of Surface Analysis: The Principal Techniques, deals with the characterisation and understanding of the outer layers of substrates, how they react, look and function which are all of interest to surface scientists. Within this comprehensive text, experts in each analysis area introduce the theory and practice of the principal techniques that have shown themselves to be effective in both basic research and in applied surface analysis. Examples of analysis are provided to facilitate the understanding of this topic and to show readers how they c

  10. Principal bundles the classical case

    CERN Document Server

    Sontz, Stephen Bruce

    2015-01-01

    This introductory graduate level text provides a relatively quick path to a special topic in classical differential geometry: principal bundles.  While the topic of principal bundles in differential geometry has become classic, even standard, material in the modern graduate mathematics curriculum, the unique approach taken in this text presents the material in a way that is intuitive for both students of mathematics and of physics. The goal of this book is to present important, modern geometric ideas in a form readily accessible to students and researchers in both the physics and mathematics communities, providing each with an understanding and appreciation of the language and ideas of the other.

  11. Isolation of Corynebacterium Xerosis from Jordanian Soil and a Study on its Antimicrobial Activity against a Range of Bacteria and Fungi

    International Nuclear Information System (INIS)

    El-Banna, Nasser

    2004-01-01

    A bacterial strain which has been identified as Corneybacterium Xerosis NB-2 was isolated from a soil sample from Jerash Private University, Jerash, Jordan. This isolate was found to produce an antimicrobial substance active only against filamentous fungi and yeasts (Aspergillus niger SQ 40, Fusarium oxysporium SQ11, Verticillium dahliae SQ 42, Saccharomyces SQ 46 and Candida albicans SQ 47). However, all tested gram-positive bacteria and gram negative bacteria (Bacillus megaterium SQ5, Bacillus cereus SQ6, Staphylococcus aureus SQ9, Streptococcus pyogens SQ10, Eschericshia coli SQ 22, Klepsiella spp SQ33 and SQ33 and Pseudonomas mallei SQ 34) were found to be resistant. In batch culture, the isolated NB-2 produced the antimicrobial substance late in the growth phase and antimicrobial activity of Corynebacterium Xerosis against filamentous fungi and yeasts which was not previously described. (author)

  12. The use of LANDSAT-1 imagery in mapping and managing soil and range resources in the Sand Hills region of Nebraska

    Science.gov (United States)

    Seevers, P. M. (Principal Investigator); Drew, J. V.

    1976-01-01

    The author has identified the following significant results. Evaluation of ERTS-1 imagery for the Sand Hills region of Nebraska has shown that the data can be used to effectively measure several parameters of inventory needs. (1) Vegetative biomass can be estimated with a high degree of confidence using computer compatable tape data. (2) Soils can be mapped to the subgroup level with high altitude aircraft color infrared photography and to the association level with multitemporal ERTS-1 imagery. (3) Water quality in Sand Hills lakes can be estimated utilizing computer compatable tape data. (4) Center pivot irrigation can be inventoried from satellite data and can be monitored regarding site selection and relative success of establishment from high altitude aircraft color infrared photography. (5) ERTS-1 data is of exceptional value in wide-area inventory of natural resource data in the Sand Hills region of Nebraska.

  13. PCB in soils and estimated soil-air exchange fluxes of selected PCB congeners in the south of Sweden

    International Nuclear Information System (INIS)

    Backe, Cecilia; Cousins, Ian T.; Larsson, Per

    2004-01-01

    PCB concentrations were studied in different soils to determine the spatial variation over a region of approximately 11 000 km 2 . PCB congener pattern was used to illustrate the spatial differences, as shown by principal component analysis (PCA). The relationship to different soil parameters was studied. PCB concentrations in soil showed a large variation between sampling-areas with median concentrations ranging between 2.3 and 332 ng g -1 (dw). Highest concentrations were found at two sites with sandy soils, one with extremely high organic carbon content. Both sites were located on the west coast of southern Sweden. Soils with similar soil textures (i.e. sandy silt moraine) did not show any significant differences in PCB concentrations. PCB congener composition was shown to differ between sites, with congener patterns almost site-specific. PCB in air and precipitation was measured and the transfer of chemicals between the soil and air compartments was estimated. Soil-air fugacity quotient calculations showed that the PCBs in the soil consistently had a higher fugacity than the PCBs in the air, with a median quotient value of 2.7. The gaseous fluxes between soil and air were estimated using standard modelling equations and a net soil-air flux estimated by subtracting bulk deposition from gaseous soil-air fluxes. It was shown that inclusion of vertical sorbed phase transport of PCBs in the soil had a large effect on the direction of the net soil-air exchange fluxes. - Soil-air exchange of PCBs is investigated and modelled across Sweden

  14. Effect of Nano-Carbon on Water Holding Capacity in a Sandy Soil of the Loess Plateau

    Directory of Open Access Journals (Sweden)

    Beibei Zhou

    2017-10-01

    Full Text Available The poor water retention capacity of sandy soils commonly aggregate soil erosion and ecological environment on the Chinese Loess Plateau. Due to its strong capacity for absorption and large specific surface area, the use of nanocarbon made of coconut shell as a soil amendment that could improve water retention was investigated. Soil column experiments were conducted in which a layer of nanocarbon mixed well with the soil was formed at a depth of 20 cm below the soil surface. Four different nanocarbon contents by weight (0%, 0.1%, 0.5%, and 1% and five thicknesses of the nanocarbon- soil mixture layer ranging from 1 to 5 cm were considered. Cumulative infiltration and soil water content distributions were determined when water was added to soil columns. Soil Water Characteristic Curves (SWCC were obtained using the centrifuge method. The principal results showed that the infiltration rate and cumulative infiltration increased with the increases of nanocarbon contents, to the thicknesses of the nano carbon-soil mixture layer. Soil water contents that below the soil-nano carbon layer decreased sharply. Both the Brooks-Corey and van Genuchten models could describe well the SWCC of the disturbed sandy soil with various nano carbon contents. Both the saturated water content (θs, residual water content (θr and empirical parameter (α increased with increasing nano carbon content, while the pore-size distribution parameter (n decreased. The available soil water contents were efficiently increased with the increase in nanocarbon contents.

  15. Proposal to evaluate the use of ERTS-A imagery in mapping and managing soil and range resources in the Sand Hills Region of Nebraska

    Science.gov (United States)

    Drew, J. V. (Principal Investigator)

    1973-01-01

    The author has identified the following significant results. There appears to be a direct relationship between densitometry values obtained with MSS band 5 imagery and forage density for those range sites measured on the imagery, provided site category identification is indicated by other forms of imagery or ground truth. Overlap of density values for different site categories with differing forage condition classes does not allow assigning a given forage density value for a given densitometer value unless the range site category is known.

  16. Least limiting water range and physical quality of soil under groundcover management systems in citrus Intervalo hídrico ótimo e qualidade física do solo em sistemas de manejo nas entrelinhas de citros

    Directory of Open Access Journals (Sweden)

    Jonez Fidalski

    2010-08-01

    Full Text Available Machinery-based farming operations used for perennial fruit crops often damage soils, particularly if the soil is wet and prone to compaction. We hypothesized that perennial vegetation growing in the interrows of orange orchards can mitigate the soil physical degradation from machinery traffic. The objective of this study was to investigate the effects of different groundcover management systems on the soil physical quality indicators including the least limiting water range (LLWR. An experiment was started in 1993 in a Typic Paleudult to evaluate three groundcover management systems: Bahia grass (Paspalum notatum with mowing, perennial peanut (Arachis pintoi, and natural regrowth in which weeds were controlled by herbicide. The experimental design was randomized complete block with three replications. In May 2003, 216 undisturbed soil samples were collected at 0-0.15-m depths under and between wheel tracks in the orchard interrows. The soil bulk density, soil organic carbon content, resistance to penetration, soil water retention curve and soil resistance to penetration curve were determined in order to estimate the LLWR. The higher LLWR under wheel tracks in Bahia grass compared to perennial peanut or natural regrowth suggest that a better soil physical quality was achieved with Bahia grass.Operações motomecanizadas utilizadas no manejo das entrelinhas dos pomares de frutas com freqüência causam a degradação física do solo, especialmente quando realizadas com o solo úmido e suscetível à compactação. A hipótese desse estudo é que a manutenção da vegetação permanente nas entrelinhas do pomar pode mitigar a degradação física do solo causada pelo tráfego de máquinas. O objetivo desse estudo é verificar o efeito de diferentes sistemas de manejo da cobertura permanente das entrelinhas sobre o intervalo hídrico ótimo (IHO e a qualidade física do solo. Um experimento foi iniciado em 1993 num Argissolo Vermelho distr

  17. Fractal scaling of particle size distribution and relationships with topsoil properties affected by biological soil crusts.

    Directory of Open Access Journals (Sweden)

    Guang-Lei Gao

    Full Text Available BACKGROUND: Biological soil crusts are common components of desert ecosystem; they cover ground surface and interact with topsoil that contribute to desertification control and degraded land restoration in arid and semiarid regions. METHODOLOGY/PRINCIPAL FINDINGS: To distinguish the changes in topsoil affected by biological soil crusts, we compared topsoil properties across three types of successional biological soil crusts (algae, lichens, and mosses crust, as well as the referenced sandland in the Mu Us Desert, Northern China. Relationships between fractal dimensions of soil particle size distribution and selected soil properties were discussed as well. The results indicated that biological soil crusts had significant positive effects on soil physical structure (P<0.05; and soil organic carbon and nutrients showed an upward trend across the successional stages of biological soil crusts. Fractal dimensions ranged from 2.1477 to 2.3032, and significantly linear correlated with selected soil properties (R(2 = 0.494∼0.955, P<0.01. CONCLUSIONS/SIGNIFICANCE: Biological soil crusts cause an important increase in soil fertility, and are beneficial to sand fixation, although the process is rather slow. Fractal dimension proves to be a sensitive and useful index for quantifying changes in soil properties that additionally implies desertification. This study will be essential to provide a firm basis for future policy-making on optimal solutions regarding desertification control and assessment, as well as degraded ecosystem restoration in arid and semiarid regions.

  18. School Uniforms: Guidelines for Principals.

    Science.gov (United States)

    Essex, Nathan L.

    2001-01-01

    Principals desiring to develop a school-uniform policy should involve parents, teachers, community leaders, and student representatives; beware restrictions on religious and political expression; provide flexibility and assistance for low-income families; implement a pilot program; align the policy with school-safety issues; and consider legal…

  19. The Principal and Tort Liability.

    Science.gov (United States)

    Stern, Ralph D.

    The emphasis of this chapter is on the tort liability of principals, especially their commission of unintentional torts or torts resulting from negligent conduct. A tort is defined as a wrongful act, not including a breach of contract or trust, which results in injury to another's person, property, or reputation and for which the injured party is…

  20. Teachers' Perspectives on Principal Mistreatment

    Science.gov (United States)

    Blase, Joseph; Blase, Jo

    2006-01-01

    Although there is some important scholarly work on the problem of workplace mistreatment/abuse, theoretical or empirical work on abusive school principals is nonexistent. Symbolic interactionism was the theoretical structure for the present study. This perspective on social research is founded on three primary assumptions: (1) individuals act…

  1. Principal minors and rhombus tilings

    International Nuclear Information System (INIS)

    Kenyon, Richard; Pemantle, Robin

    2014-01-01

    The algebraic relations between the principal minors of a generic n × n matrix are somewhat mysterious, see e.g. Lin and Sturmfels (2009 J. Algebra 322 4121–31). We show, however, that by adding in certain almost principal minors, the ideal of relations is generated by translations of a single relation, the so-called hexahedron relation, which is a composition of six cluster mutations. We give in particular a Laurent-polynomial parameterization of the space of n × n matrices, whose parameters consist of certain principal and almost principal minors. The parameters naturally live on vertices and faces of the tiles in a rhombus tiling of a convex 2n-gon. A matrix is associated to an equivalence class of tilings, all related to each other by Yang–Baxter-like transformations. By specializing the initial data we can similarly parameterize the space of Hermitian symmetric matrices over R,C or H the quaternions. Moreover by further specialization we can parametrize the space of positive definite matrices over these rings. This article is part of a special issue of Journal of Physics A: Mathematical and Theoretical devoted to ‘Cluster algebras mathematical physics’. (paper)

  2. Soil Quality Evaluation Using the Soil Management Assessment Framework (SMAF in Brazilian Oxisols with Contrasting Texture

    Directory of Open Access Journals (Sweden)

    Maurício Roberto Cherubin

    Full Text Available ABSTRACT The Soil Management Assessment Framework (SMAF was developed in the U.S.A. and has been used as a tool for assessing and quantifying changes in soil quality/health (SQ induced by land uses and agricultural practices in that region and elsewhere throughout the world. An initial study using SMAF in Brazil was recently published, but additional research for a variety of soils and management systems is still needed. Our objective was to use data from five studies in southern Brazil to evaluate the potential of SMAF for assessing diverse land-use and management practices on SQ. The studies examined were: (i horizontal and vertical distribution of soil properties in a long-term orange orchard; (ii impacts of long-term land-use change from native vegetation to agricultural crops on soil properties; (iii effects of short-term tillage on soil properties in a cassava production area; (iv changes in soil properties due to mineral fertilizer and pig slurry application coupled with soil tillage practices; and (v row and inter-row sowing effects on soil properties in a long-term no-tillage area. The soils were classified as Oxisols, with clay content ranging from 180 to 800 g kg-1. Six SQ indicators [pH(H2O, P, K, bulk density, organic C, and microbial biomass] were individually scored using SMAF curves and integrated into an overall Soil Quality Index (SQI focusing on chemical, physical, and biological sectors. The SMAF was sensitive for detecting SQ changes induced by different land uses and management practices within this wide textural range of Brazilian Oxisols. The SMAF scoring curve algorithms properly transformed the indicator values expressed in different units into unitless scores ranging from 0-1, thus enabling the individual indicators to be combined into an overall index for evaluating land-use and management effects on soil functions. Soil sector scores (i.e., chemical, physical, and biological identify the principal soil limitations

  3. Influence of long-range atmospheric transportation (LRAT) on mono-to octa-chlorinated PCDD/Fs levels and distributions in soil around Qinghai Lake, China

    DEFF Research Database (Denmark)

    Han, Ying; Liu, Wenbin; Hansen, Hans Chr. Bruun

    2016-01-01

    Long-range atmospheric transportation (LRAT) of persistent organic pollutants followed by their deposition in cold, arid regions is of wide concern. This problem occurs at Qinghai Lake in the northeastern Tibetan Plateau, a sparsely populated area with extreme weather conditions and little curren...

  4. Nitrogen and phosphorus capture and recovery efficiencies, and crop responses to a range of soil fertility management strategies in sub-Saharan Africa

    NARCIS (Netherlands)

    Chikowo, R.; Corbeels, M.; Mapfumo, P.; Tittonell, P.A.; Vanlauwe, B.; Giller, K.E.

    2010-01-01

    This paper examines a number of agronomic field experiments in different regions of sub-Saharan Africa to assess the associated variability in the efficiencies with which applied and available nutrients are taken up by crops under a wide range of management and environmental conditions. We consider

  5. No difference in the competitive ability of introduced and native Trifolium provenances when grown with soil biota from their introduced and native ranges

    NARCIS (Netherlands)

    Shelby, Natasha; Hulme, P.E.; Putten, van der W.H.; McGinn, Kevin J.; Weser, Carolin; Duncan, R.P.

    2016-01-01

    The evolution of increased competitive ability (EICA) hypothesis could explain why some introduced plant species perform better outside their native ranges. EICA proposes that introduced plants escape specialist pathogens or herbivores leading to selection for resources to be reallocated away from

  6. Proposal to evaluate the use of ERTS-1 imagery in mapping and managing soil and range resources in the Sand Hills region of Nebraska

    Science.gov (United States)

    Drew, J. V. (Principal Investigator)

    1974-01-01

    The author has identified the following significant results. Increase in radiance values is directly related to decrease in vegetative biomass, though not in a linear manner. Should the relationship hold true over an entire growing season, this would allow an extremely rapid evaluation of range condition. Computer access by remote terminal would allow production of this type of range condition evaluation in near real time, which is essential if grazing practice decisions are to be made based on satellite imagery acquisition. Negating the manipulation of photographic products appears to be the logical way to provide satellite imagery data to the user in near real time. There appears to be a direct linear relationship between radiance values of bands 4 and 5 and increase in total inorganic ions (6 ions) of lakes in the Sand hills region. Consistent ion concentration of lakes during the year could allow their radiance values to serve as a means of equating radiance values from image to image.

  7. Soil washing

    International Nuclear Information System (INIS)

    Neuman, R.S.; Diel, B.N.; Halpern, Y.

    1992-01-01

    Disposal of soils or sludges contaminated with organic and inorganic compounds is a major problem for environmental remedial activities, hazardous waste generators, and the disposal industry. This paper reports that many of these wastes can be effectively treated utilizing soil washing technology. CWM has been developing soil washing technology over the past few years, with extensive work being conducted on the bench scale. These studies have demonstrated consistently high removal efficiencies (95-99%) for a wide variety of PCB and petroleum hydrocarbon contaminated waste. Recently, a comprehensive study examining the removal of both organic and inorganic contraminants from two different types of surrogate soil matrices was completed. In addition to establishing the range of contaminants that can be removed from soil, a method for surfactant/water separation was evaluated. For example, using a thermal phase separation method, approximately 90% of the surfactant could be recovered from the water

  8. Examining the Relationship between Principal Leadership and School Climate

    Science.gov (United States)

    Lane, Eric S.

    2016-01-01

    The purpose of this quantitative study was to explore the relationship between transformative school principal leadership and school climate. The population of this study consisted of two middle schools with grades ranging from six through eight and one high school with grades ranging from nine through twelve. These schools are within the state of…

  9. Developing Principal Instructional Leadership through Collaborative Networking

    Science.gov (United States)

    Cone, Mariah Bahar

    2010-01-01

    This study examines what occurs when principals of urban schools meet together to learn and improve their instructional leadership in collaborative principal networks designed to support, sustain, and provide ongoing principal capacity building. Principal leadership is considered second only to teaching in its ability to improve schools, yet few…

  10. 31 CFR 19.995 - Principal.

    Science.gov (United States)

    2010-07-01

    ... SUSPENSION (NONPROCUREMENT) Definitions § 19.995 Principal. Principal means— (a) An officer, director, owner, partner, principal investigator, or other person within a participant with management or supervisory... 31 Money and Finance: Treasury 1 2010-07-01 2010-07-01 false Principal. 19.995 Section 19.995...

  11. 22 CFR 208.995 - Principal.

    Science.gov (United States)

    2010-04-01

    ... 22 Foreign Relations 1 2010-04-01 2010-04-01 false Principal. 208.995 Section 208.995 Foreign...) Definitions § 208.995 Principal. Principal means— (a) An officer, director, owner, partner, principal investigator, or other person within a participant with management or supervisory responsibilities related to a...

  12. 29 CFR 1471.995 - Principal.

    Science.gov (United States)

    2010-07-01

    ... SUSPENSION (NONPROCUREMENT) Definitions § 1471.995 Principal. Principal means— (a) An officer, director, owner, partner, principal investigator, or other person within a participant with management or... 29 Labor 4 2010-07-01 2010-07-01 false Principal. 1471.995 Section 1471.995 Labor Regulations...

  13. 21 CFR 1404.995 - Principal.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 9 2010-04-01 2010-04-01 false Principal. 1404.995 Section 1404.995 Food and...) Definitions § 1404.995 Principal. Principal means— (a) An officer, director, owner, partner, principal investigator, or other person within a participant with management or supervisory responsibilities related to a...

  14. 22 CFR 1006.995 - Principal.

    Science.gov (United States)

    2010-04-01

    ... 22 Foreign Relations 2 2010-04-01 2010-04-01 true Principal. 1006.995 Section 1006.995 Foreign... § 1006.995 Principal. Principal means— (a) An officer, director, owner, partner, principal investigator, or other person within a participant with management or supervisory responsibilities related to a...

  15. 2 CFR 180.995 - Principal.

    Science.gov (United States)

    2010-01-01

    ... 2 Grants and Agreements 1 2010-01-01 2010-01-01 false Principal. 180.995 Section 180.995 Grants and Agreements OFFICE OF MANAGEMENT AND BUDGET GOVERNMENTWIDE GUIDANCE FOR GRANTS AND AGREEMENTS... § 180.995 Principal. Principal means— (a) An officer, director, owner, partner, principal investigator...

  16. 34 CFR 85.995 - Principal.

    Science.gov (United States)

    2010-07-01

    ... 34 Education 1 2010-07-01 2010-07-01 false Principal. 85.995 Section 85.995 Education Office of...) Definitions § 85.995 Principal. Principal means— (a) An officer, director, owner, partner, principal investigator, or other person within a participant with management or supervisory responsibilities related to a...

  17. 22 CFR 1508.995 - Principal.

    Science.gov (United States)

    2010-04-01

    ... 22 Foreign Relations 2 2010-04-01 2010-04-01 true Principal. 1508.995 Section 1508.995 Foreign...) Definitions § 1508.995 Principal. Principal means— (a) An officer, director, owner, partner, principal investigator, or other person within a participant with management or supervisory responsibilities related to a...

  18. Principal chiral model on superspheres

    International Nuclear Information System (INIS)

    Mitev, V.; Schomerus, V.; Quella, T.

    2008-09-01

    We investigate the spectrum of the principal chiral model (PCM) on odd-dimensional superspheres as a function of the curvature radius R. For volume-filling branes on S 3 vertical stroke 2 , we compute the exact boundary spectrum as a function of R. The extension to higher dimensional superspheres is discussed, but not carried out in detail. Our results provide very convincing evidence in favor of the strong-weak coupling duality between supersphere PCMs and OSP(2S+2 vertical stroke 2S) Gross-Neveu models that was recently conjectured by Candu and Saleur. (orig.)

  19. Interpretable functional principal component analysis.

    Science.gov (United States)

    Lin, Zhenhua; Wang, Liangliang; Cao, Jiguo

    2016-09-01

    Functional principal component analysis (FPCA) is a popular approach to explore major sources of variation in a sample of random curves. These major sources of variation are represented by functional principal components (FPCs). The intervals where the values of FPCs are significant are interpreted as where sample curves have major variations. However, these intervals are often hard for naïve users to identify, because of the vague definition of "significant values". In this article, we develop a novel penalty-based method to derive FPCs that are only nonzero precisely in the intervals where the values of FPCs are significant, whence the derived FPCs possess better interpretability than the FPCs derived from existing methods. To compute the proposed FPCs, we devise an efficient algorithm based on projection deflation techniques. We show that the proposed interpretable FPCs are strongly consistent and asymptotically normal under mild conditions. Simulation studies confirm that with a competitive performance in explaining variations of sample curves, the proposed FPCs are more interpretable than the traditional counterparts. This advantage is demonstrated by analyzing two real datasets, namely, electroencephalography data and Canadian weather data. © 2015, The International Biometric Society.

  20. Underwater Ranging

    OpenAIRE

    S. P. Gaba

    1984-01-01

    The paper deals with underwater laser ranging system, its principle of operation and maximum depth capability. The sources of external noise and methods to improve signal-to-noise ratio are also discussed.

  1. Female Traditional Principals and Co-Principals: Experiences of Role Conflict and Job Satisfaction

    Science.gov (United States)

    Eckman, Ellen Wexler; Kelber, Sheryl Talcott

    2010-01-01

    This paper presents a secondary analysis of survey data focusing on role conflict and job satisfaction of 102 female principals. Data were collected from 51 female traditional principals and 51 female co-principals. By examining the traditional and co-principal leadership models as experienced by female principals, this paper addresses the impact…

  2. On Bayesian Principal Component Analysis

    Czech Academy of Sciences Publication Activity Database

    Šmídl, Václav; Quinn, A.

    2007-01-01

    Roč. 51, č. 9 (2007), s. 4101-4123 ISSN 0167-9473 R&D Projects: GA MŠk(CZ) 1M0572 Institutional research plan: CEZ:AV0Z10750506 Keywords : Principal component analysis ( PCA ) * Variational bayes (VB) * von-Mises–Fisher distribution Subject RIV: BC - Control Systems Theory Impact factor: 1.029, year: 2007 http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6V8V-4MYD60N-6&_user=10&_coverDate=05%2F15%2F2007&_rdoc=1&_fmt=&_orig=search&_sort=d&view=c&_acct=C000050221&_version=1&_urlVersion=0&_userid=10&md5=b8ea629d48df926fe18f9e5724c9003a

  3. Principals: Learn P.R. Survival Skills.

    Science.gov (United States)

    Reep, Beverly B.

    1988-01-01

    School building level public relations depends on the principal or vice principal. Strategies designed to enhance school public relations programs include linking school and community, working with the press, and keeping morale high inside the school. (MLF)

  4. Numerical evaluation of state boundary surface through rotation of principal stress axes in sand

    International Nuclear Information System (INIS)

    Sadrnejad, S. A.

    2001-01-01

    In applying shear stress to saturated soil with arbitrary stress paths, the prediction of the exact value of strains is difficult because of mainly its stress path dependent nature. Rotation of the principal stress axes during shearing of the soil is a feature of stress paths associated with many field loading situations. A proper understanding of the effects of principal stress rotation on soil behavior can be provided if the anisotropy existing prior to stress rotation and induced anisotropy due to plastic flow in soil are clearly understood and modeled. A multi laminate based model for soil is developed and used to compute and present the influence of rotation of principal stress axes on the plastic behavior of soil. This is fulfilled by distributing the effects of boundary condition changes into several predefined sampling orientations at one point and summing the micro-results up as the macro-result. The validity of the presented model examined by comparing numerical and test results showing the mentioned aspect. In this paper, the state boundary surface is numerically obtained by a multi laminate based model capable of predicting the behavior of sand under the influences of rotation of the direction of principal stress axes and induced anisotropy. the predicted numerical results are tally in agreement with experiments

  5. Mapping ash properties using principal components analysis

    Science.gov (United States)

    Pereira, Paulo; Brevik, Eric; Cerda, Artemi; Ubeda, Xavier; Novara, Agata; Francos, Marcos; Rodrigo-Comino, Jesus; Bogunovic, Igor; Khaledian, Yones

    2017-04-01

    In post-fire environments ash has important benefits for soils, such as protection and source of nutrients, crucial for vegetation recuperation (Jordan et al., 2016; Pereira et al., 2015a; 2016a,b). The thickness and distribution of ash are fundamental aspects for soil protection (Cerdà and Doerr, 2008; Pereira et al., 2015b) and the severity at which was produced is important for the type and amount of elements that is released in soil solution (Bodi et al., 2014). Ash is very mobile material, and it is important were it will be deposited. Until the first rainfalls are is very mobile. After it, bind in the soil surface and is harder to erode. Mapping ash properties in the immediate period after fire is complex, since it is constantly moving (Pereira et al., 2015b). However, is an important task, since according the amount and type of ash produced we can identify the degree of soil protection and the nutrients that will be dissolved. The objective of this work is to apply to map ash properties (CaCO3, pH, and select extractable elements) using a principal component analysis (PCA) in the immediate period after the fire. Four days after the fire we established a grid in a 9x27 m area and took ash samples every 3 meters for a total of 40 sampling points (Pereira et al., 2017). The PCA identified 5 different factors. Factor 1 identified high loadings in electrical conductivity, calcium, and magnesium and negative with aluminum and iron, while Factor 3 had high positive loadings in total phosphorous and silica. Factor 3 showed high positive loadings in sodium and potassium, factor 4 high negative loadings in CaCO3 and pH, and factor 5 high loadings in sodium and potassium. The experimental variograms of the extracted factors showed that the Gaussian model was the most precise to model factor 1, the linear to model factor 2 and the wave hole effect to model factor 3, 4 and 5. The maps produced confirm the patternd observed in the experimental variograms. Factor 1 and 2

  6. Principals as Assessment Leaders in Rural Schools

    Science.gov (United States)

    Renihan, Patrick; Noonan, Brian

    2012-01-01

    This article reports a study of rural school principals' assessment leadership roles and the impact of rural context on their work. The study involved three focus groups of principals serving small rural schools of varied size and grade configuration in three systems. Principals viewed assessment as a matter of teacher accountability and as a…

  7. Principal Stability and the Rural Divide

    Science.gov (United States)

    Pendola, Andrew; Fuller, Edward J.

    2018-01-01

    This article examines the unique features of the rural school context and how these features are associated with the stability of principals in these schools. Given the small but growing literature on the characteristics of rural principals, this study presents an exploratory analysis of principal stability across schools located in different…

  8. New Principal Coaching as a Safety Net

    Science.gov (United States)

    Celoria, Davide; Roberson, Ingrid

    2015-01-01

    This study examines new principal coaching as an induction process and explores the emotional dimensions of educational leadership. Twelve principal coaches and new principals--six of each--participated in this qualitative study that employed emergent coding (Creswell, 2008; Denzin, 2005; Glaser & Strauss, 1998; Spradley, 1979). The major…

  9. 12 CFR 561.39 - Principal office.

    Science.gov (United States)

    2010-01-01

    ... 12 Banks and Banking 5 2010-01-01 2010-01-01 false Principal office. 561.39 Section 561.39 Banks and Banking OFFICE OF THRIFT SUPERVISION, DEPARTMENT OF THE TREASURY DEFINITIONS FOR REGULATIONS AFFECTING ALL SAVINGS ASSOCIATIONS § 561.39 Principal office. The term principal office means the home...

  10. The Principal as Academician: The Renewed Voice.

    Science.gov (United States)

    McAvoy, Brenda, Ed.

    This collection of essays was written by principals who participated in the 1986-87 Humanities Seminar sponsored by the Principals' Institute of Georgia State University. The focus was "The Evolution of Intellectual Leadership." The roles of the principal as philosopher, historian, ethnician, writer and team member are examined through…

  11. Principal-Counselor Collaboration and School Climate

    Science.gov (United States)

    Rock, Wendy D.; Remley, Theodore P.; Range, Lillian M.

    2017-01-01

    Examining whether principal-counselor collaboration and school climate were related, researchers sent 4,193 surveys to high school counselors in the United States and received 419 responses. As principal-counselor collaboration increased, there were increases in counselors viewing the principal as supportive, the teachers as regarding one another…

  12. Modelling Monthly Mental Sickness Cases Using Principal ...

    African Journals Online (AJOL)

    The methodology was principal component analysis (PCA) using data obtained from the hospital to estimate regression coefficients and parameters. It was found that the principal component regression model that was derived was good predictive tool. The principal component regression model obtained was okay and this ...

  13. Principals' Collaborative Roles as Leaders for Learning

    Science.gov (United States)

    Kitchen, Margaret; Gray, Susan; Jeurissen, Maree

    2016-01-01

    This article draws on data from three multicultural New Zealand primary schools to reconceptualize principals' roles as leaders for learning. In doing so, the writers build on Sinnema and Robinson's (2012) article on goal setting in principal evaluation. Sinnema and Robinson found that even principals hand-picked for their experience fell short on…

  14. Perceptions of Beginning Public School Principals.

    Science.gov (United States)

    Lyons, James E.

    1993-01-01

    Summarizes a study to determine principal's perceptions of their competency in primary responsibility areas and their greatest challenges and frustrations. Beginning principals are challenged by delegating responsibilities and becoming familiar with the principal's role, the local school, and school operations. Their major frustrations are role…

  15. Teacher Supervision Practices and Principals' Characteristics

    Science.gov (United States)

    April, Daniel; Bouchamma, Yamina

    2015-01-01

    A questionnaire was used to determine the individual and collective teacher supervision practices of school principals and vice-principals in Québec (n = 39) who participated in a research-action study on pedagogical supervision. These practices were then analyzed in terms of the principals' sociodemographic and socioprofessional characteristics…

  16. Leadership Coaching for Principals: A National Study

    Science.gov (United States)

    Wise, Donald; Cavazos, Blanca

    2017-01-01

    Surveys were sent to a large representative sample of public school principals in the United States asking if they had received leadership coaching. Comparison of responses to actual numbers of principals indicates that the sample represents the first national study of principal leadership coaching. Results indicate that approximately 50% of all…

  17. 41 CFR 105-68.995 - Principal.

    Science.gov (United States)

    2010-07-01

    ... 41 Public Contracts and Property Management 3 2010-07-01 2010-07-01 false Principal. 105-68.995 Section 105-68.995 Public Contracts and Property Management Federal Property Management Regulations System...-GOVERNMENTWIDE DEBARMENT AND SUSPENSION (NONPROCUREMENT) Definitions § 105-68.995 Principal. Principal means— (a...

  18. A principal-agent Model of corruption

    NARCIS (Netherlands)

    Groenendijk, Nico

    1997-01-01

    One of the new avenues in the study of political corruption is that of neo-institutional economics, of which the principal-agent theory is a part. In this article a principal-agent model of corruption is presented, in which there are two principals (one of which is corrupting), and one agent (who is

  19. Principal component regression analysis with SPSS.

    Science.gov (United States)

    Liu, R X; Kuang, J; Gong, Q; Hou, X L

    2003-06-01

    The paper introduces all indices of multicollinearity diagnoses, the basic principle of principal component regression and determination of 'best' equation method. The paper uses an example to describe how to do principal component regression analysis with SPSS 10.0: including all calculating processes of the principal component regression and all operations of linear regression, factor analysis, descriptives, compute variable and bivariate correlations procedures in SPSS 10.0. The principal component regression analysis can be used to overcome disturbance of the multicollinearity. The simplified, speeded up and accurate statistical effect is reached through the principal component regression analysis with SPSS.

  20. Perspectives on Principal Instructional Leadership in Vietnam: A Preliminary Model

    Science.gov (United States)

    Hallinger, Philip; Walker, Allan; Nguyen, Dao Thi Hong; Truong, Thang; Nguyen, Thi Thinh

    2017-01-01

    Purpose: Worldwide interest in principal instructional leadership has led to global dissemination of related research findings despite their concentration in a limited set of western cultural contexts. An urgent challenge in educational leadership and management lies in expanding the range of national settings for investigations of instructional…

  1. Teaching Principal Components Using Correlations.

    Science.gov (United States)

    Westfall, Peter H; Arias, Andrea L; Fulton, Lawrence V

    2017-01-01

    Introducing principal components (PCs) to students is difficult. First, the matrix algebra and mathematical maximization lemmas are daunting, especially for students in the social and behavioral sciences. Second, the standard motivation involving variance maximization subject to unit length constraint does not directly connect to the "variance explained" interpretation. Third, the unit length and uncorrelatedness constraints of the standard motivation do not allow re-scaling or oblique rotations, which are common in practice. Instead, we propose to motivate the subject in terms of optimizing (weighted) average proportions of variance explained in the original variables; this approach may be more intuitive, and hence easier to understand because it links directly to the familiar "R-squared" statistic. It also removes the need for unit length and uncorrelatedness constraints, provides a direct interpretation of "variance explained," and provides a direct answer to the question of whether to use covariance-based or correlation-based PCs. Furthermore, the presentation can be made without matrix algebra or optimization proofs. Modern tools from data science, including heat maps and text mining, provide further help in the interpretation and application of PCs; examples are given. Together, these techniques may be used to revise currently used methods for teaching and learning PCs in the behavioral sciences.

  2. An employment of distribution coefficients for the valuation of the soils with regard to their radiological risks

    International Nuclear Information System (INIS)

    Carini, F.; Silva, S.; Fontana, P.

    1985-01-01

    As a preliminary step it has been demonstrated that the distribution coefficients may prove useful items in order to classify soils to a radioprotective purpose. We have obtained transfer factors from soils, which were different according to their principal chemical and physical features, into plants typical of the middle Po valley agriculture. By utilizing these factors as guiding indexes,it is possible, through cluster analysis, to determine a range of soils with regard to their radiological risk starting only from the pedologic parameters

  3. Phytotoxic effects of (+/--catechin in vitro, in soil, and in the field.

    Directory of Open Access Journals (Sweden)

    Inderjit

    Full Text Available BACKGROUND: Exploring the residence time of allelochemicals released by plants into different soils, episodic exposure of plants to allelochemicals, and the effects of allelochemicals in the field has the potential to improve our understanding of interactions among plants. METHODOLOGY/PRINCIPAL FINDINGS: We conducted experiments in India and the USA to understand the dynamics of soil concentrations and phytotoxicity of (+/--catechin, an allelopathic compound exuded from the roots of Centaurea maculosa, to other plants in vitro and in soil. Experiments with single and pulsed applications into soil were conducted in the field. Experimental application of (+/--catechin to soils always resulted in concentrations that were far lower than the amounts added but within the range of reported natural soil concentrations. Pulses replenished (+/--catechin levels in soils, but consistently at concentrations much lower than were applied, and even pulsed concentrations declined rapidly. Different natural soils varied substantially in the retention of (+/--catechin after application but consistent rapid decreases in concentrations over time suggested that applied experimental concentrations may overestimate concentrations necessary for phytotoxicity by over an order of magnitude. (+/--Catechin was not phytotoxic to Bambusa arundinacea in natural Indian soil in a single pulse, but soil concentrations at the time of planting seeds were either undetectable or very low. However, a single dose of (+/--catechin suppressed the growth of bamboo in sand, in soil mixed with organic matter, and Koeleria macrantha in soils from Montana and Romania, and in field applications at 40 microg l(-1. Multiple pulses of (+/--catechin were inhibitory at very low concentrations in Indian soil. CONCLUSIONS/SIGNIFICANCE: Our results demonstrate that (+/--catechin is highly dynamic in natural soils, but is phytotoxic well below natural concentrations measured in some soils and applied

  4. Phytotoxic Effects of (±)-Catechin In vitro, in Soil, and in the Field

    Science.gov (United States)

    Inderjit; Pollock, Jarrod L.; Callaway, Ragan M.; Holben, William

    2008-01-01

    Background Exploring the residence time of allelochemicals released by plants into different soils, episodic exposure of plants to allelochemicals, and the effects of allelochemicals in the field has the potential to improve our understanding of interactions among plants. Methodology/Principal Findings We conducted experiments in India and the USA to understand the dynamics of soil concentrations and phytotoxicity of (±)-catechin, an allelopathic compound exuded from the roots of Centaurea maculosa, to other plants in vitro and in soil. Experiments with single and pulsed applications into soil were conducted in the field. Experimental application of (±)-catechin to soils always resulted in concentrations that were far lower than the amounts added but within the range of reported natural soil concentrations. Pulses replenished (±)-catechin levels in soils, but consistently at concentrations much lower than were applied, and even pulsed concentrations declined rapidly. Different natural soils varied substantially in the retention of (±)-catechin after application but consistent rapid decreases in concentrations over time suggested that applied experimental concentrations may overestimate concentrations necessary for phytotoxicity by over an order of magnitude. (±)-Catechin was not phytotoxic to Bambusa arundinacea in natural Indian soil in a single pulse, but soil concentrations at the time of planting seeds were either undetectable or very low. However, a single dose of (±)-catechin suppressed the growth of bamboo in sand, in soil mixed with organic matter, and Koeleria macrantha in soils from Montana and Romania, and in field applications at 40 µg l−1. Multiple pulses of (±)-catechin were inhibitory at very low concentrations in Indian soil. Conclusions/Significance Our results demonstrate that (±)-catechin is highly dynamic in natural soils, but is phytotoxic well below natural concentrations measured in some soils and applied at low concentrations in

  5. Iron and silicon isotope behaviour accompanying weathering in Icelandic soils, and the implications for iron export from peatlands

    Science.gov (United States)

    Opfergelt, S.; Williams, H. M.; Cornelis, J. T.; Guicharnaud, R. A.; Georg, R. B.; Siebert, C.; Gislason, S. R.; Halliday, A. N.; Burton, K. W.

    2017-11-01

    Incipient warming of peatlands at high latitudes is expected to modify soil drainage and hence the redox conditions, which has implications for Fe export from soils. This study uses Fe isotopes to assess the processes controlling Fe export in a range of Icelandic soils including peat soils derived from the same parent basalt, where Fe isotope variations principally reflect differences in weathering and drainage. In poorly weathered, well-drained soils (non-peat soils), the limited Fe isotope fractionation in soil solutions relative to the bulk soil (Δ57Fesolution-soil = -0.11 ± 0.12‰) is attributed to proton-promoted mineral dissolution. In the more weathered poorly drained soils (peat soils), the soil solutions are usually lighter than the bulk soil (Δ57Fesolution-soil = -0.41 ± 0.32‰), which indicates that Fe has been mobilised by reductive mineral dissolution and/or ligand-controlled dissolution. The results highlight the presence of Fe-organic complexes in solution in anoxic conditions. An additional constraint on soil weathering is provided by Si isotopes. The Si isotope composition of the soil solutions relative to the soil (Δ30Sisolution-soil = 0.92 ± 0.26‰) generally reflects the incorporation of light Si isotopes in secondary aluminosilicates. Under anoxic conditions in peat soils, the largest Si isotope fractionation in soil solutions relative to the bulk soil is observed (Δ30Sisolution-soil = 1.63 ± 0.40‰) and attributed to the cumulative contribution of secondary clay minerals and amorphous silica precipitation. Si supersaturation in solution with respect to amorphous silica is reached upon freezing when Al availability to form aluminosilicates is limited by the affinity of Al for metal-organic complexes. Therefore, the precipitation of amorphous silica in peat soils indirectly supports the formation of metal-organic complexes in poorly drained soils. These observations highlight that in a scenario of decreasing soil drainage with

  6. Modeling Soil-Landscape Relations in the Sonoran Desert, Arizona, USA

    Science.gov (United States)

    Regmi, N. R.; Rasmussen, C.

    2015-12-01

    Digital soil mapping (DSM) techniques that integrate remotely sensed surface topography and reflectance, and map soil-landscape associations have the potential in improve understanding of critical zone evolution and landscape processes. The goal of this study was to understand the soil-geomorphic evolution of Quaternary alluvial and eolian deposits in the Sonoran Desert using a data-driven DSM technique and mapping of soil-landscape relationships. An iterative principal component analysis (iPCA) data reduction routine was developed and implemented for a set of LiDAR elevation- and Landsat ETM+-derived environmental covariates that characterize soil-landscape variability. Principal components that explain more than 95% of the soil-landscape variability were then integrated and classified based on an ISODATA (Iterative Self-Organizing Data) unsupervised technique. The classified map was then segmented based on a region growing algorithm and multi-scale maps of soil-landscape relations were developed, which then compared with maps of major arid-region landforms that can be identified on aerial photographs and satellite images by their distinguishing tone and texture, and in the field by their distinguishing surface and sub-surface soil physical, chemical and biological properties. The approach identified and mapped the soil-landscape variability of alluvial and eolian landscapes, and illustrated the applicability of coupling covariate selection and integration by iPCA, ISODATA classifications of integrated layers, and image segmentation for effective spatial prediction of soil-landscape characteristics. The approach developed here is data-driven, cost- and time-effective, applicable for multi-scale mapping, allows incorporation of wide variety of covariates, and provides accurate quantitative prediction of wide range of soil-landscape attributes that are necessary for hydrologic models, land and ecosystem management decisions, and hazard assessment.

  7. Optimal interface between principal deterrent systems and material accounting

    International Nuclear Information System (INIS)

    Deiermann, P.J.; Opelka, J.H.

    1983-01-01

    The purpose of this study is to find an optimal blend between three safeguards systems for special nuclear material (SNM), the material accounting system and the physical security and material control systems. The latter two are denoted as principal deterrent systems. The optimization methodology employed is a two-stage decision algorithm, first an explicit maximization of expected diverter benefits and subsequently a minimization of expected defender costs for changes in material accounting procedures and incremental improvements in the principal deterrent systems. The probability of diverter success function dependent upon the principal deterrents and material accounting system variables is developed. Within the range of certainty of the model, existing material accounting, material control and physical security practices are justified

  8. Trace elements in brazilian soils

    International Nuclear Information System (INIS)

    Rocha, Geraldo Cesar

    1995-01-01

    A literature revision on trace elements (Zn, B, Mn, Mo, Cu, Fe, and Cl) in Brazilian soils was prepared, with special attention to the chemical form and range in the soil, extraction methods and correlation of the amount in soils with soil properties

  9. Reduction of symplectic principal R-bundles

    International Nuclear Information System (INIS)

    Lacirasella, Ignazio; Marrero, Juan Carlos; Padrón, Edith

    2012-01-01

    We describe a reduction process for symplectic principal R-bundles in the presence of a momentum map. These types of structures play an important role in the geometric formulation of non-autonomous Hamiltonian systems. We apply this procedure to the standard symplectic principal R-bundle associated with a fibration π:M→R. Moreover, we show a reduction process for non-autonomous Hamiltonian systems on symplectic principal R-bundles. We apply these reduction processes to several examples. (paper)

  10. Assessment of the quality of the Harran Plain soils under long-term cultivation.

    Science.gov (United States)

    Bilgili, Ali Volkan; Küçük, Çiğdem; Van Es, Harold M

    2017-08-19

    Soil quality refers to the ability of soils to perform their functions well. The soils of the Harran Plain, Turkey, have been put into intensive crop production with the introduction of an irrigation scheme and become increasingly degraded due to unsustainable management and cropping systems that resulted in the loss of production potential. The goal of this study was to quantify the quality of common soil series in the Plain using soil quality indexes (SQI) and to compare SQIs of two long-term crop rotations, cotton and wheat-corn cultivation, and different soil types. Over 400 samples were collected at a 0- to 30-cm depth and analyzed for 31 soil variables. The best representative soil quality variables forming a minimum data set (MDS) were selected using principal component analysis (PCA), and soil quality scores were obtained using both linear and non-linear scoring functions. The MDS included three physical (hydraulic conductivity, bulk density, and plant available water content), two biological (soil organic matter and catalase enzyme activity), and nine chemical soil quality indicators (CEC, pH, plant available Cu and Fe, exchangeable Na and K, soluble Ca, Mg, and Na). Because of the low level of SOM, soil qualities were overall low with indexes obtained using two scoring functions ranging from 38.0/100 to 48.7/100. Correlations between SQI obtained using two approaches (linear vs. non-linear; r > 0.61) and using two data sets (all data vs. MDS; r > 0.79) were high. Non-linear scoring functions were more sensitive to management impacts. ANOVA models testing the individual impacts of soil types and crop management on soil quality were statistically different (p < 0.01), but the models including interactions were not. Overall, the fields under cotton cultivation were generally associated with higher clay contents and had the lowest SQIs as a result of intensive cultivation.

  11. Home range and travels

    Science.gov (United States)

    Stickel, L.F.; King, John A.

    1968-01-01

    . Peromyscus generally used and maintained several or many different home sites and refuges in various parts of their home ranges, and frequently shifted about so that their principal activities centered on different sets of holes at different times. Once established, many Peromyscus remained in the same general area for a long time, perhaps for the duration of their lives. Extent of their travels in different directions and intensity of use of different portions of their home ranges varied within a general area in response to habitat changes, loss of neighbors, or other factors. Various authors have obtained both direct and indirect evidence of territoriality, in some degree, among certain species of Peromyscus. Young mice dispersed from their birth sites to establish home ranges of their own. Adults also sometimes left their home areas; some re-established elsewhere; others returned after exploratory travels. Most populations contained a certain proportion of transients; these may have been wanderers or individuals exploring out from established home ranges or seeking new ones. When areas were depopulated by removal trapping, other Peromyscus invaded. Invasion rates generally followed seasonal trends of reproduction and population density. Peromyscus removed from their home areas and released elsewhere returned home from various distances, but fewer returned from greater distances than from nearby; speed of return increased with successive trials. The consensus from present evidence is that ho-ming is made possible by a combination of random wandering and familiarity with a larger area than the day-to-day range. Records of juvenile wanderings during the dispersal phase and of adult explorations very nearly encompassed the distances over which any substantial amount of successful homing occurred. Methods of measuring sizes of home ranges and the limitations of these measurements were discussed in brief synopsis. It was co

  12. GPS test range mission planning

    Science.gov (United States)

    Roberts, Iris P.; Hancock, Thomas P.

    The principal features of the Test Range User Mission Planner (TRUMP), a PC-resident tool designed to aid in deploying and utilizing GPS-based test range assets, are reviewed. TRUMP features time history plots of time-space-position information (TSPI); performance based on a dynamic GPS/inertial system simulation; time history plots of TSPI data link connectivity; digital terrain elevation data maps with user-defined cultural features; and two-dimensional coverage plots of ground-based test range assets. Some functions to be added during the next development phase are discussed.

  13. New pulser for principal PO power

    International Nuclear Information System (INIS)

    Coudert, G.

    1984-01-01

    The pulser of the principal power of the PS is the unit that makes it possible to generate the reference function of the voltage of the principal magnet. This function depends on time and on the magnetic field of the magnet. It also generates various synchronization and reference pulses

  14. Principals: Human Capital Managers at Every School

    Science.gov (United States)

    Kimball, Steven M.

    2011-01-01

    Being a principal is more than just being an instructional leader. Principals also must manage their schools' teaching talent in a strategic way so that it is linked to school instructional improvement strategies, to the competencies needed to enact the strategies, and to success in boosting student learning. Teacher acquisition and performance…

  15. Integrating Technology: The Principals' Role and Effect

    Science.gov (United States)

    Machado, Lucas J.; Chung, Chia-Jung

    2015-01-01

    There are many factors that influence technology integration in the classroom such as teacher willingness, availability of hardware, and professional development of staff. Taking into account these elements, this paper describes research on technology integration with a focus on principals' attitudes. The role of the principal in classroom…

  16. Building Leadership Capacity to Support Principal Succession

    Science.gov (United States)

    Escalante, Karen Elizabeth

    2016-01-01

    This study applies transformational leadership theory practices, specifically inspiring a shared vision, modeling the way and enabling others to act to examine the purposeful ways in which principals work to build the next generation of teacher leaders in response to the dearth of K-12 principals. The purpose of this study was to discover how one…

  17. Deformation quantization of principal fibre bundles

    International Nuclear Information System (INIS)

    Weiss, S.

    2007-01-01

    Deformation quantization is an algebraic but still geometrical way to define noncommutative spacetimes. In order to investigate corresponding gauge theories on such spaces, the geometrical formulation in terms of principal fibre bundles yields the appropriate framework. In this talk I will explain what should be understood by a deformation quantization of principal fibre bundles and how associated vector bundles arise in this context. (author)

  18. Primary School Principals' Self-Monitoring Skills

    Science.gov (United States)

    Konan, Necdet

    2015-01-01

    The aim of the present study is to identify primary school principals' self-monitoring skills. The study adopted the general survey model and its population comprised primary school principals serving in the city of Diyarbakir, Turkey, while 292 of these constituted the sample. Self-Monitoring Scale was used as the data collection instrument. In…

  19. Revising the Role of Principal Supervisor

    Science.gov (United States)

    Saltzman, Amy

    2016-01-01

    In Washington, D.C., and Tulsa, Okla., districts whose efforts are supported by the Wallace Foundation, principal supervisors concentrate on bolstering their principals' work to improve instruction, as opposed to focusing on the managerial or operational aspects of running a school. Supervisors oversee fewer schools, which enables them to provide…

  20. An Examination of Principal Job Satisfaction

    Science.gov (United States)

    Pengilly, Michelle M.

    2010-01-01

    As education continues to succumb to deficits in budgets and increasingly high levels of student performance to meet the federal and state mandates, the quest to sustain and retain successful principals is imperative. The National Association of School Boards (1999) portrays effective principals as "linchpins" of school improvement and…

  1. Do Principals Fire the Worst Teachers?

    Science.gov (United States)

    Jacob, Brian A.

    2011-01-01

    This article takes advantage of a unique policy change to examine how principals make decisions regarding teacher dismissal. In 2004, the Chicago Public Schools (CPS) and Chicago Teachers Union signed a new collective bargaining agreement that gave principals the flexibility to dismiss probationary teachers for any reason and without the…

  2. Artful Dodges Principals Use to Beat Bureaucracy.

    Science.gov (United States)

    Ficklen, Ellen

    1982-01-01

    A study of Chicago (Illinois) principals revealed many ways principals practiced "creative insubordination"--avoiding following instructions but still getting things done. Among the dodges are deliberately missing deadlines, following orders literally, ignoring channels to procure teachers or materials, and using community members to…

  3. Women principals' reflections of curriculum management challenges ...

    African Journals Online (AJOL)

    This study reports the reflections of grade 6 rural primary principals in Mpumalanga province. A qualitative method of inquiry was used in this article, where data were collected using individual interviews with three principals and focus group discussions with the school management teams (SMTs) of three primary schools.

  4. The Succession of a School Principal.

    Science.gov (United States)

    Fauske, Janice R.; Ogawa, Rodney T.

    Applying theory from organizational and cultural perspectives to succession of principals, this study observes and records the language and culture of a small suburban elementary school. The study's procedures included analyses of shared organizational understandings as well as identification of the principal's influence on the school. Analyses of…

  5. Principals' Perceptions of School Public Relations

    Science.gov (United States)

    Morris, Robert C.; Chan, Tak Cheung; Patterson, Judith

    2009-01-01

    This study was designed to investigate school principals' perceptions on school public relations in five areas: community demographics, parental involvement, internal and external communications, school council issues, and community resources. Findings indicated that principals' concerns were as follows: rapid population growth, change of…

  6. How Not to Prepare School Principals

    Science.gov (United States)

    Davis, Stephen H.; Leon, Ronald J.

    2011-01-01

    Instead of focusing on how principals should be trained, an contrarian view is offered, grounded upon theoretical perspectives of experiential learning, and in particular, upon the theory of andragogy. A brief parable of the DoNoHarm School of Medicine is used as a descriptive analog for many principal preparation programs in America. The…

  7. Social Media Strategies for School Principals

    Science.gov (United States)

    Cox, Dan; McLeod, Scott

    2014-01-01

    The purpose of this qualitative study was to describe, analyze, and interpret the experiences of school principals who use multiple social media tools with stakeholders as part of their comprehensive communications practices. Additionally, it examined why school principals have chosen to communicate with their stakeholders through social media.…

  8. New Principals' Perspectives of Their Multifaceted Roles

    Science.gov (United States)

    Gentilucci, James L.; Denti, Lou; Guaglianone, Curtis L.

    2013-01-01

    This study utilizes Symbolic Interactionism to explore perspectives of neophyte principals. Findings explain how these perspectives are modified through complex interactions throughout the school year, and they also suggest preparation programs can help new principals most effectively by teaching "soft" skills such as active listening…

  9. The Principal's Guide to Grant Success.

    Science.gov (United States)

    Bauer, David G.

    This book provides principals of public and private elementary and middle schools with a step-by-step approach for developing a system that empowers faculty, staff, and the school community in attracting grant funds. Following the introduction, chapter 1 discusses the principal's role in supporting grantseeking. Chapter 2 describes how to…

  10. State-Space Estimation of Soil Organic Carbon Stock

    Science.gov (United States)

    Ogunwole, Joshua O.; Timm, Luis C.; Obidike-Ugwu, Evelyn O.; Gabriels, Donald M.

    2014-04-01

    Understanding soil spatial variability and identifying soil parameters most determinant to soil organic carbon stock is pivotal to precision in ecological modelling, prediction, estimation and management of soil within a landscape. This study investigates and describes field soil variability and its structural pattern for agricultural management decisions. The main aim was to relate variation in soil organic carbon stock to soil properties and to estimate soil organic carbon stock from the soil properties. A transect sampling of 100 points at 3 m intervals was carried out. Soils were sampled and analyzed for soil organic carbon and other selected soil properties along with determination of dry aggregate and water-stable aggregate fractions. Principal component analysis, geostatistics, and state-space analysis were conducted on the analyzed soil properties. The first three principal components explained 53.2% of the total variation; Principal Component 1 was dominated by soil exchange complex and dry sieved macroaggregates clusters. Exponential semivariogram model described the structure of soil organic carbon stock with a strong dependence indicating that soil organic carbon values were correlated up to 10.8m.Neighbouring values of soil organic carbon stock, all waterstable aggregate fractions, and dithionite and pyrophosphate iron gave reliable estimate of soil organic carbon stock by state-space.

  11. Accumulation, allocation, and risk assessment of polycyclic aromatic hydrocarbons (PAHs in soil-Brassica chinensis system.

    Directory of Open Access Journals (Sweden)

    Juan Zhang

    Full Text Available Farmland soil and leafy vegetables accumulate more polycyclic aromatic hydrocarbons (PAHs in suburban sites. In this study, 13 sampling areas were selected from vegetable fields in the outskirts of Xi'an, the largest city in northwestern China. The similarity of PAH composition in soil and vegetation was investigated through principal components analysis and redundancy analysis (RDA, rather than discrimination of PAH congeners from various sources. The toxic equivalent quantity of PAHs in soil ranged from 7 to 202 μg/kg d.w., with an average of 41 μg/kg d.w., which exceeded the agricultural/horticultural soil acceptance criteria for New Zealand. However, the cancer risk level posed by combined direct ingestion, dermal contact, inhalation of soil particles, and inhalation of surface soil vapor met the rigorous international criteria (1 × 10(-6. The concentration of total PAHs was (1052 ± 73 μg/kg d.w. in vegetation (mean ± standard error. The cancer risks posed by ingestion of vegetation ranged from 2×10-5 to 2 × 10(-4 with an average of 1.66 × 10(-4, which was higher than international excess lifetime risk limits for carcinogens (1 × 10(-4. The geochemical indices indicated that the PAHs in soil and vegetables were mainly from vehicle and crude oil combustion. Both the total PAHs in vegetation and bioconcentration factor for total PAHs (the ratio of total PAHs in vegetation to total PAHs in soil increased with increasing pH as well as decreasing sand in soil. The total variation in distribution of PAHs in vegetation explained by those in soil reached 98% in RDA, which was statistically significant based on Monte Carlo permutation. Common pollution source and notable effects of soil contamination on vegetation would result in highly similar distribution of PAHs in soil and vegetation.

  12. Applying Krumboltz's Theory of Career Decision Making (CDM) to the Longevity of Principals in the North American Division of Seventh-Day Adventists

    Science.gov (United States)

    Saint-Ulysse, Sadrail

    2017-01-01

    Problem: Ledesma (2011) reports that principals' average tenure in Adventist schools in North America "ranges from 2.5-4.0 years. Elementary principals remain in leadership for 2.5 years, day academy principals stay for 3.6 years, and boarding academy principals leave after 4.0 years" (p, 8). Ledesma also noted that the length of tenure…

  13. Restoring Soil Quality to Mitigate Soil Degradation

    Directory of Open Access Journals (Sweden)

    Rattan Lal

    2015-05-01

    Full Text Available Feeding the world population, 7.3 billion in 2015 and projected to increase to 9.5 billion by 2050, necessitates an increase in agricultural production of ~70% between 2005 and 2050. Soil degradation, characterized by decline in quality and decrease in ecosystem goods and services, is a major constraint to achieving the required increase in agricultural production. Soil is a non-renewable resource on human time scales with its vulnerability to degradation depending on complex interactions between processes, factors and causes occurring at a range of spatial and temporal scales. Among the major soil degradation processes are accelerated erosion, depletion of the soil organic carbon (SOC pool and loss in biodiversity, loss of soil fertility and elemental imbalance, acidification and salinization. Soil degradation trends can be reversed by conversion to a restorative land use and adoption of recommended management practices. The strategy is to minimize soil erosion, create positive SOC and N budgets, enhance activity and species diversity of soil biota (micro, meso, and macro, and improve structural stability and pore geometry. Improving soil quality (i.e., increasing SOC pool, improving soil structure, enhancing soil fertility can reduce risks of soil degradation (physical, chemical, biological and ecological while improving the environment. Increasing the SOC pool to above the critical level (10 to 15 g/kg is essential to set-in-motion the restorative trends. Site-specific techniques of restoring soil quality include conservation agriculture, integrated nutrient management, continuous vegetative cover such as residue mulch and cover cropping, and controlled grazing at appropriate stocking rates. The strategy is to produce “more from less” by reducing losses and increasing soil, water, and nutrient use efficiency.

  14. High School Principals Who Stay: Stability in a Time of Change

    Science.gov (United States)

    Luebke, Patricia A.

    2013-01-01

    This qualitative study explored the institutional factors, personal characteristics, and work-related relationships of high school principals that led to their longer than usual tenure in their positions. Data were gathered from interviews with ten high school principals who had served in their positions for a range of 8 to 23 years, much longer…

  15. The Principals and Practice of Distributed High Throughput Computing

    CERN Multimedia

    CERN. Geneva

    2016-01-01

    The potential of Distributed Processing Systems to deliver computing capabilities with qualities ranging from high availability and reliability to easy expansion in functionality and capacity were recognized and formalized in the 1970’s. For more three decade these principals Distributed Computing guided the development of the HTCondor resource and job management system. The widely adopted suite of software tools offered by HTCondor are based on novel distributed computing technologies and are driven by the evolving needs of High Throughput scientific applications. We will review the principals that underpin our work, the distributed computing frameworks and technologies we developed and the lessons we learned from delivering effective and dependable software tools in an ever changing landscape computing technologies and needs that range today from a desktop computer to tens of thousands of cores offered by commercial clouds. About the speaker Miron Livny received a B.Sc. degree in Physics and Mat...

  16. Preparing Principals as Instructional Leaders: Perceptions of University Faculty, Expert Principals, and Expert Teacher Leaders

    Science.gov (United States)

    Taylor Backor, Karen; Gordon, Stephen P.

    2015-01-01

    Although research has established links between the principal's instructional leadership and student achievement, there is considerable concern in the literature concerning the capacity of principal preparation programs to prepare instructional leaders. This study interviewed educational leadership faculty as well as expert principals and teacher…

  17. Exploring the Impact of Applicants' Gender and Religion on Principals' Screening Decisions for Assistant Principal Applicants

    Science.gov (United States)

    Bon, Susan C.

    2009-01-01

    In this experimental study, a national random sample of high school principals (stratified by gender) were asked to evaluate hypothetical applicants whose resumes varied by religion (Jewish, Catholic, nondenominational) and gender (male, female) for employment as assistant principals. Results reveal that male principals rate all applicants higher…

  18. Principal Self-Efficacy and Work Engagement: Assessing a Norwegian Principal Self-Efficacy Scale

    Science.gov (United States)

    Federici, Roger A.; Skaalvik, Einar M.

    2011-01-01

    One purpose of the present study was to develop and test the factor structure of a multidimensional and hierarchical Norwegian Principal Self-Efficacy Scale (NPSES). Another purpose of the study was to investigate the relationship between principal self-efficacy and work engagement. Principal self-efficacy was measured by the 22-item NPSES. Work…

  19. Principal Time Management Skills: Explaining Patterns in Principals' Time Use, Job Stress, and Perceived Effectiveness

    Science.gov (United States)

    Grissom, Jason A.; Loeb, Susanna; Mitani, Hajime

    2015-01-01

    Purpose: Time demands faced by school principals make principals' work increasingly difficult. Research outside education suggests that effective time management skills may help principals meet job demands, reduce job stress, and improve their performance. The purpose of this paper is to investigate these hypotheses. Design/methodology/approach:…

  20. Short-chain chlorinated paraffins (SCCPs) in surface soil from a background area in China: occurrence, distribution, and congener profiles.

    Science.gov (United States)

    Wang, Xue-Tong; Zhang, Yuan; Miao, Yi; Ma, Ling-Ling; Li, Yuan-Cheng; Chang, Yue-Ya; Wu, Ming-Hong

    2013-07-01

    Short-chain chlorinated paraffins (SCCPs) are extremely complex technical mixtures of polychlorinated n-alkanes with carbon chain lengths from C10 to C13 and chlorine content between 49 and 70%. SCCPs are under consideration for inclusion in the Stockholm Convention on persistent organic pollutants. SCCPs have been used extensively in industrial production, but little is known about the pollution level in soil environment in China. In this study, levels and distribution of SCCPs in soil samples from Chongming Island were analyzed. Concentrations of total SCCPs in soil samples ranged from 0.42 to 420 ng g(-1), with a median of 9.6 ng g(-1). The ubiquitous occurrence of SCCPs in Chongming Island implied that long-range atmospheric transport and soil-air exchange may be the most important pathways for SCCP contamination in the background area. The localized SCCP contamination could be derived from an unidentified source. Hierarchical cluster analysis indicated that C13- and C11-congeners were predominant in most soils and C10- and C12-congeners dominated in the remaining soils. Cl7- and Cl8-congeners were on the average the most dominant chlorine congeners in nearly all soils. Principal component analysis suggested that the separation of even and odd carbon chain congeners occurred during long-range atmospheric transport and aging in soil in the study area.

  1. Wildfire effects on lipid composition and hydrophobicity of bulk soil and soil size fractions under Quercus suber cover (SW-Spain).

    Science.gov (United States)

    Jiménez-Morillo, Nicasio T; Spangenberg, Jorge E; Miller, Ana Z; Jordán, Antonio; Zavala, Lorena M; González-Vila, Francisco J; González-Pérez, José A

    2017-11-01

    Soil water repellency (hydrophobicity) prevents water from wetting or infiltrating soils, triggering changes in the ecosystems. Fire may develop, enhance or destroy hydrophobicity in previously wettable or water-repellent soils. Soil water repellency is mostly influenced by the quality and quantity of soil organic matter, particularly the lipid fraction. Here we report the results of a study on the effect of fire on the distribution of soil lipids and their role in the hydrophobicity grade of six particle size fractions (2-1, 1-0.5, 0.5-0.25, 0.25-0.1, 0.1-0.05 and fractions. Soil lipids were Soxhlet extracted with a dichloromethane-methanol mixture. Fatty acids (FAs) and neutral lipids were separated, derivatized, identified and quantified by gas chromatography/mass spectrometry and gas chromatography/flame ionization detection. The hydrophobicity values of soil samples and fractions were statistically different (P fractions. All samples displayed a similar distribution of FAs, straight-chain saturated acids in the C 14 -C 32 range, and neutral lipids (n-alkan-1-ols, n-alkanes), only differing in their relative abundances. Among possible biogeochemical mechanisms responsible for the changes in soil lipids, the observed depletion of long chain FAs (C ≥24 ) in the coarse fraction is best explained by thermal cracking caused by the heat of the fire. The enrichment of long chain FAs observed in other fractions suggests possible exogenous additions of charred, lipid-rich, material, like cork suberin or other plant-derived macromolecules (cutins). Principal component analysis was used to study the relationships between hydrophobicity with soil organic matter and its different components. Extractable organic matter (EOM) and specifically long chain FAs content were positively correlated to soil hydrophobicity. Therefore, the latter could be used as biomarkers surrogated to hydrophobicity in sandy soils. Copyright © 2017 Elsevier Inc. All rights reserved.

  2. Temporal dynamics of the compositions and activities of soil microbial communities post-application of the insecticide chlorantraniliprole in paddy soils.

    Science.gov (United States)

    Wu, Meng; Liu, Jia; Li, Weitao; Liu, Ming; Jiang, Chunyu; Li, Zhongpei

    2017-10-01

    Chlorantraniliprole (CAP) is a newly developed insecticide widely used in rice fields in China. There has been few studies evaluating the toxicological effects of CAP on soil-associated microbes. An 85-day microcosm experiment was performed to reveal the dissipation dynamics of CAP in three types of paddy soils in subtropical China. The effects of CAP on microbial activities (microbial biomass carbon-MBC, basal soil respiration-BSR, microbial metabolic quotient-qCO 2 , acid phosphatase and sucrose invertase activities) in the soils were periodically evaluated. Microbial phospholipid fatty acid (PLFA) analysis was used to evaluate the change of soil microbial community composition on day 14 and 50 of the experiment. CAP residues were extracted using the quick, easy, cheap, effective, rugged, and safe (QuChERS) method and quantification was measured by high performance liquid chromatography (HPLC). The half-lives (DT 50 ) of CAP were in the range of 41.0-53.0 days in the three soils. The results showed that CAP did not impart negative effects on MBC during the incubation. CAP inhibited BSR, qCO 2 , acid phosphatase and sucrose invertase activities in the first 14 days of incubation in all the soils. After day 14, the soil microbial parameters of CAP-treated soils became statistically at par with their controls. Principal component analysis (PCA) determining abundance of biomarker PLFAs indicated that the application of CAP significantly changed the compositions of microbial communities in all three paddy soils on day 14 but the compositions of soil microbial communities recovered by day 50. This study indicates that CAP does not ultimately impair microbial activities and microbial compositions of these three paddy soil types. Copyright © 2017 Elsevier Inc. All rights reserved.

  3. Genesis and properties of wetland soils by VIS-NIR-SWIR as a technique for environmental monitoring.

    Science.gov (United States)

    Demattê, José Alexandre Melo; Horák-Terra, Ingrid; Beirigo, Raphael Moreira; Terra, Fabrício da Silva; Marques, Karina Patrícia Prazeres; Fongaro, Caio Troula; Silva, Alexandre Christófaro; Vidal-Torrado, Pablo

    2017-07-15

    Wetlands are important ecosystems characterized by redoximorphic environments producing typical soil forming processes and organic carbon accumulation. Assessments and management of these areas are dependent on knowledge about soil characteristics and variability. By reflectance spectroscopy, information about soils can be obtained since their spectral behaviors are directly related to their chemical, physical, and mineralogical properties reflecting the pedogenetic processes and environment conditions. Our aims were: (a) to characterize the main soil classes of wetlands regarding their spectral behaviors in VIS-NIR-SWIR (350-2500 nm) and relate them to pedogenesis and environmental conditions, (b) to determine spectral ranges (bands) with greater expression of the main soil properties, (c) to identify spectral variations and similarities between hydromorphic soils from wetlands and other soils under different moisture conditions, and (d) to propose spectral models to quantify some chemical and physical soil properties used as environmental quality indicators. Nine soil profiles from the Pantanal region (Mato Grosso State, Brazil) and one from the Serra do Espinhaço Meridional (Minas Gerais State, Brazil) were investigated. Spectral morphology interpretation allowed identifying horizon differences regarding shape, absorption features and reflectance intensity. Some pedogenetic processes of wetland soils related to organic carbon accumulation and oxide iron variation were identified by spectra. Principal Component Analysis allowed discriminating soils from wetland and outside this area (oxidic environment). Quantification of organic carbon was possible with R 2 of 0.90 and low error. Quantification of clay content was masked by soils with organic carbon content over 2% where it was not possible to quantify with high R 2 and low error both properties when dataset has soil samples with high organic carbon content. By reflectance spectroscopy, important

  4. The Changing Model of Soil

    Science.gov (United States)

    Richter, D. D.; Yaalon, D.

    2012-12-01

    The contemporary genetic model of soil is changing rapidly in response to advances in soil science and to human and environmental forcings in the 21st century (Richter and Yaalon, 2012). Three ongoing changes in the model of soil include that: (1) lower soil boundaries are much deeper than the solum, historically the O to B horizons, (2) most soils are polygenetic paleosols, products of soil-forming processes that have ranged widely over soils' lifetimes, and (3) soils are globally human-natural bodies, no longer natural bodies. Together, these changes in the model of soil mean that human forcings are a global wave of soil polygenesis altering fluxes of matter and energy and transforming soil thermodynamics as potentially very deep systems. Because soils are non-linear systems resulting from high-order interactions of physics, chemistry, and biology, trajectories of how human forcings alter soils over decades are not readily predictable and require long-term soil observations. There is much to learn about how soils are changing internally as central components of management systems and externally in relation to wider environments. To be critical, research has been remarkably superficial in studies of soil, reductionist in approach, and lacking in time-series observations of responses to soil management. While this criticism may sound negative, it creates significant opportunities for contemporary soil scientists.

  5. Responses of calotropis procera and cassia senna to some soil factors in central Sudan

    International Nuclear Information System (INIS)

    Hayati, A. A.; Yahia, A. Y.

    2002-01-01

    The responses of calotropis procera and cassia senna to soil ph, Ca, Mg, K, Na, Mn, Fe, NH 4 -N and P were investigated in three sites in central Sudan, namely Omdurman, Wadelmajzob (Wad Medani) and Kosti. The investigation was carried out by chemical analysis of soil and pant samples collected randomly from 25 sampling points at each site. The data of the soil chemical analysis were analysed using the principal component analysis (PCA). The PCA reflected some what low range of variation in the distribution of the soil nutrient within each of the three investigated sites. Chemical analysis of C. procera and C. senna plants, collected from three investigated sites, showed that they have different levels of nutrients uptake. Although C. senna tends to have low mineral requirements compared with C. procera. it was completely absent from Kosti sit. This may be due to the acidity and high Mn levels at this site.(Author)

  6. Comparative Analysis of Principals' Management Strategies in ...

    African Journals Online (AJOL)

    It was recommended among others that principals of secondary schools should adopt all the management strategies in this study as this will improve school administration and consequently students‟ academic performance. Keywords: Management Strategies; Secondary Schools; Administrative Effectiveness ...

  7. The Relationship between Principals' Managerial Approaches and ...

    African Journals Online (AJOL)

    Nekky Umera

    Egerton University, P. O. Box 16568, NAKURU KENYA bosirej@yahoo.com ... teacher and parental input while it was negatively correlated with the level of .... principal's attitude, gender qualifications, and leadership experience (Green,. 1999 ...

  8. First-Year Principal Encounters Homophobia

    Science.gov (United States)

    Retelle, Ellen

    2011-01-01

    A 1st-year principal encounters homonegativity and an ethical dilemma when she attempts to terminate a teacher because of the teacher's inadequate and ineffective teaching. The teacher responds by threatening to "out" Ms. L. to the parents.

  9. Integrating Data Transformation in Principal Components Analysis

    KAUST Repository

    Maadooliat, Mehdi; Huang, Jianhua Z.; Hu, Jianhua

    2015-01-01

    Principal component analysis (PCA) is a popular dimension reduction method to reduce the complexity and obtain the informative aspects of high-dimensional datasets. When the data distribution is skewed, data transformation is commonly used prior

  10. Spatial control of groundwater contamination, using principal

    Indian Academy of Sciences (India)

    Spatial control of groundwater contamination, using principal component analysis ... anthropogenic (agricultural activities and domestic wastewaters), and marine ... The PC scores reflect the change of groundwater quality of geogenic origin ...

  11. Principal Hawaiian Islands Geoid Heights (GEOID96)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This 2' geoid height grid for the Principal Hawaiian Islands is distributed as a GEOID96 model. The computation used 61,000 terrestrial and marine gravity data held...

  12. Environmental concentration and atmospheric deposition of halogenated flame retardants in soil from Nepal: Source apportionment and soil-air partitioning.

    Science.gov (United States)

    Yadav, Ishwar Chandra; Devi, Ningombam Linthoingambi; Li, Jun; Zhang, Gan

    2018-02-01

    While various investigations have been driven on polybrominated diphenyl ethers (PBDEs) and other flame retardants (FRs) in different framework around the world, information about contamination and fate of PBDEs and other FRs in developing countries especially in the Indian subcontinent is uncommon. Nepal being located in the Indian subcontinent, very little is known about contamination level of semi-volatile organic pollutants discharged into the environment. This motivated us to investigate the environmental fate of halogenated flame retardant (HFRs) in Nepalese condition. In this study, we investigated the concentration, fate, and sources of 9 PBDEs, 2 dechlorane plus isomers (DPs), and 6 novel brominated flame retardants (NBFRs). Moreover, air-soil exchange and soil-air partitioning were also evaluated to characterize the pattern of air-soil exchange and environmental fate. In general, the concentrations of NBFRs in soil were more prevalent than PBDEs and DPs, and accounted 95% of ∑HFRs. By and large, the concentrations of NBFRs and DPs were measured high in Kathmandu, while PBDEs level exceeded in Pokhara. Principal component analysis (PCA) study suggested contributions from commercial penta-, octa-, and deca-BDEs products and de-bromination of highly brominated PBDEs as the significant source of PBDEs. Likewise, low f anti ratio suggested DPs in soil might have originated from long-range atmospheric transport from remote areas, while high levels of decabromodiphenyl ethane (DBDPE) in soil were linked with the use of wide varieties of consumer products. The estimated fugacity fraction (ff) for individual HFR was quite lower (soil is overwhelming. Soil-air partitioning study revealed neither octanol-air partition coefficient (K OA ) nor black carbon partition coefficient (K BC-A ) is an appropriate surrogate for soil organic matter (SOM), subsequently, absorption by SOM has no or little role in the partitioning of HFRs. Copyright © 2017 Elsevier Ltd. All

  13. Forest soils

    Science.gov (United States)

    Charles H. (Hobie) Perry; Michael C. Amacher

    2009-01-01

    Productive soils are the foundation of sustainable forests throughout the United States. Forest soils are generally subjected to fewer disturbances than agricultural soils, particularly those that are tilled, so forest soils tend to have better preserved A-horizons than agricultural soils. Another major contrast between forest and agricultural soils is the addition of...

  14. Soil and Soil Water Relationships

    OpenAIRE

    Easton, Zachary M.; Bock, Emily

    2017-01-01

    Discusses the relationships between soil, water and plants. Discusses different types of soil, and how these soils hold water. Provides information about differences in soil drainage. Discusses the concept of water balance.

  15. Phosphorus dynamics of representative volcanic ash soils through the use of conventional and isotopic techniques

    International Nuclear Information System (INIS)

    Pino, I.; Parada, A.M.; Luzio, W.

    2002-01-01

    In Chile, the total extension covered by volcanic ash soils including recent and old volcanic deposits is around 5,244,400 ha. This study was carried out in 'La Araucania and Los Lagos' regions (IX and X Regions of Chile respectively), which cover approximately 2,350,000 ha. The main chemical characteristics of these soils are: very low available P (Olsen); a high P retention capacity and a high quantity of aluminum (Al) associated to a high amount of short-range order minerals. The main objective of this study was the characterization of the P dynamics of representative volcanic soils through the use of conventional and isotopic techniques. In the X Region (Los Lagos) of Chile samples from the arable layer (0-20 cm) of eleven soils (Ultisols and Andisols) were collected. Four entire soil profiles were sampled in the IX Region (Araucania). The characterization of soils was made utuilising conventional and isotopic analyses. The P retention was over 85% in all soils, except for the Metrenco soil series (Paleudult). Nevertheless, the P retention of this soil, from 72% to 79% can be also considered high for a non-volcanic ash soil. In the same way, the Al+1/2 Fe (ox) in all profiles showed high values for non-volcanic ash soils. These results indicate the great difficulty in increasing the available P in these soils, even when high rates of phosphate fertilizers are applied. The principal P-limiting factor in both regions was the P intensity factor. (author)

  16. Effects of 10-Year Management Regimes on the Soil Seed Bank in Saline-Alkaline Grassland

    Science.gov (United States)

    Ma, Hongyuan; Yang, Haoyu; Liang, Zhengwei; Ooi, Mark K. J.

    2015-01-01

    Background Management regimes for vegetation restoration of degraded grasslands can significantly affect the process of ecological succession. However, few studies have focused on variation in the soil seed bank during vegetation restoration under different management regimes, especially in saline-alkaline grassland habitats. Our aim was to provide insights into the ecological effects of grassland management regimes on soil seed bank composition and vegetation establishment in mown, fenced, transplanted and natural grassland sites, all dominated by the perennial rhizomatous grass Leymus chinensis. Methodology We studied species composition and diversity in both the soil seed bank and aboveground vegetation in differently managed grasslands in Northeast China. An NMDS (nonmetric multidimensional scaling) was used to evaluate the relationship between species composition, soil seed banks, aboveground vegetation and soil properties. Principal Findings Fenced and mown grassland sites had high density and species richness in both the soil seed bank and aboveground vegetation. The Transplanted treatment exhibited the highest vegetation growth and seed production of the target species L. chinensis. Seeds of L. chinensis in the soil occurred only in transplanted and natural grassland. Based on the NMDS analysis, the number of species in both the soil seed bank and aboveground vegetation were significantly related to soil Na+, Cl-, RSC (residual sodium carbonate), alkalinity, ESP (exchangeable sodium percentage) and AP (available phosphorus). Conclusions Soil seed bank composition and diversity in the saline-alkaline grassland were significantly affected by the management regimes implemented, and were also significantly related to the aboveground vegetation and several soil properties. Based on vegetative growth, reproductive output and maintenance of soil seed bank, the transplanting was identified as the most effective method for relatively rapid restoration of the target

  17. Physical soil quality indicators for monitoring British soils

    Science.gov (United States)

    Corstanje, Ron; Mercer, Theresa G.; Rickson, Jane R.; Deeks, Lynda K.; Newell-Price, Paul; Holman, Ian; Kechavarsi, Cedric; Waine, Toby W.

    2017-09-01

    Soil condition or quality determines its ability to deliver a range of functions that support ecosystem services, human health and wellbeing. The increasing policy imperative to implement successful soil monitoring programmes has resulted in the demand for reliable soil quality indicators (SQIs) for physical, biological and chemical soil properties. The selection of these indicators needs to ensure that they are sensitive and responsive to pressure and change, e.g. they change across space and time in relation to natural perturbations and land management practices. Using a logical sieve approach based on key policy-related soil functions, this research assessed whether physical soil properties can be used to indicate the quality of British soils in terms of their capacity to deliver ecosystem goods and services. The resultant prioritised list of physical SQIs was tested for robustness, spatial and temporal variability, and expected rate of change using statistical analysis and modelling. Seven SQIs were prioritised: soil packing density, soil water retention characteristics, aggregate stability, rate of soil erosion, depth of soil, soil structure (assessed by visual soil evaluation) and soil sealing. These all have direct relevance to current and likely future soil and environmental policy and are appropriate for implementation in soil monitoring programmes.

  18. Physical soil quality indicators for monitoring British soils

    Directory of Open Access Journals (Sweden)

    R. Corstanje

    2017-09-01

    Full Text Available Soil condition or quality determines its ability to deliver a range of functions that support ecosystem services, human health and wellbeing. The increasing policy imperative to implement successful soil monitoring programmes has resulted in the demand for reliable soil quality indicators (SQIs for physical, biological and chemical soil properties. The selection of these indicators needs to ensure that they are sensitive and responsive to pressure and change, e.g. they change across space and time in relation to natural perturbations and land management practices. Using a logical sieve approach based on key policy-related soil functions, this research assessed whether physical soil properties can be used to indicate the quality of British soils in terms of their capacity to deliver ecosystem goods and services. The resultant prioritised list of physical SQIs was tested for robustness, spatial and temporal variability, and expected rate of change using statistical analysis and modelling. Seven SQIs were prioritised: soil packing density, soil water retention characteristics, aggregate stability, rate of soil erosion, depth of soil, soil structure (assessed by visual soil evaluation and soil sealing. These all have direct relevance to current and likely future soil and environmental policy and are appropriate for implementation in soil monitoring programmes.

  19. Scour in cohesive soils

    Science.gov (United States)

    2015-05-01

    This study of scour in cohesive soils had two objectives. The first was to introduce and demonstrate a new ex situ erosion testing device (ESTD) that can mimic the near-bed flow of open channels to erode cohesive soils within a specified range of she...

  20. Complex conductivity of soils

    NARCIS (Netherlands)

    Revil, A.; Coperey, A.; Shao, Z.; Florsch, N.; Fabricus, I.L.; Deng, Y.; Delsman, J.R.; Pauw, P.S.; Karaoulis, M.; Louw, P.G.B. de; Baaren, E.S. van; Dabekaussen, W.; Menkovic, A.; Gunnink, J.L.

    2017-01-01

    The complex conductivity of soils remains poorly known despite the growing importance of this method in hydrogeophysics. In order to fill this gap of knowledge, we investigate the complex conductivity of 71 soils samples (including four peat samples) and one clean sand in the frequency range 0.1 Hz

  1. Mass Transport within Soils

    Energy Technology Data Exchange (ETDEWEB)

    McKone, Thomas E.

    2009-03-01

    Contaminants in soil can impact human health and the environment through a complex web of interactions. Soils exist where the atmosphere, hydrosphere, geosphere, and biosphere converge. Soil is the thin outer zone of the earth's crust that supports rooted plants and is the product of climate and living organisms acting on rock. A true soil is a mixture of air, water, mineral, and organic components. The relative proportions of these components determine the value of the soil for agricultural and for other human uses. These proportions also determine, to a large extent, how a substance added to soil is transported and/or transformed within the soil (Spositio, 2004). In mass-balance models, soil compartments play a major role, functioning both as reservoirs and as the principal media for transport among air, vegetation, surface water, deeper soil, and ground water (Mackay, 2001). Quantifying the mass transport of chemicals within soil and between soil and atmosphere is important for understanding the role soil plays in controlling fate, transport, and exposure to multimedia pollutants. Soils are characteristically heterogeneous. A trench dug into soil typically reveals several horizontal layers having different colors and textures. As illustrated in Figure 1, these multiple layers are often divided into three major horizons: (1) the A horizon, which encompasses the root zone and contains a high concentration of organic matter; (2) the B horizon, which is unsaturated, lies below the roots of most plants, and contains a much lower organic carbon content; and (3) the C horizon, which is the unsaturated zone of weathered parent rock consisting of bedrock, alluvial material, glacial material, and/or soil of an earlier geological period. Below these three horizons lies the saturated zone - a zone that encompasses the area below ground surface in which all interconnected openings within the geologic media are completely filled with water. Similarly to the unsaturated

  2. the use of integrated soil fertility approach in the improvement of soil

    African Journals Online (AJOL)

    Sammy

    improvement of soil texture and structure, thus boosters food production in the ecological region. ... the farm (Strainer 1984, Nicholaida et al 1985, Juo 1987, Renand et al 1997, ... degraded each year, due principally to water and wind erosion.

  3. Promoting principals' managerial involvement in instructional improvement.

    Science.gov (United States)

    Gillat, A

    1994-01-01

    Studies of school leadership suggest that visiting classrooms, emphasizing achievement and training, and supporting teachers are important indicators of the effectiveness of school principals. The utility of a behavior-analytic program to support the enhancement of these behaviors in 2 school principals and the impact of their involvement upon teachers' and students' performances in three classes were examined in two experiments, one at an elementary school and another at a secondary school. Treatment conditions consisted of helping the principal or teacher to schedule his or her time and to use goal setting, feedback, and praise. A withdrawal design (Experiment 1) and a multiple baseline across classrooms (Experiment 2) showed that the principal's and teacher's rates of praise, feedback, and goal setting increased during the intervention, and were associated with improvements in the academic performance of the students. In the future, school psychologists might analyze the impact of involving themselves in supporting the principal's involvement in improving students' and teachers' performances or in playing a similar leadership role themselves.

  4. [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.

  5. Evaluation of soil structure in the framework of an overall soil quality rating

    DEFF Research Database (Denmark)

    Mueller, L; Shepherd, T G; Schindler, U

    2013-01-01

    Soil structure is an important aspect of agricultural soil quality, and its preservation and improvement are key to sustaining soil functions. Methods of overall soil quality assessment which include visual soil structure information can be useful tools for monitoring and managing the global soil...... resource. The aim of the paper is: (i) to demonstrate the role of visual quantification of soil structure within the procedure of the overall soil quality assessment by the Muencheberg Soil Quality Rating (M-SQR), (ii) to quantify the magnitude and variability of soil structure and overall M......-SQR on a number of agricultural research sites and (iii) to analyse the correlations of soil quality rating results with crop yields. We analysed visual soil structure and overall soil quality on a range of 20 experimental sites in seven countries. To assess visual soil structure we utilised the Visual Soil...

  6. Evaluating the Effectiveness of Traditional and Alternative Principal Preparation Programs

    Science.gov (United States)

    Pannell, Summer; Peltier-Glaze, Bernnell M.; Haynes, Ingrid; Davis, Delilah; Skelton, Carrie

    2015-01-01

    This study sought to determine the effectiveness on increasing student achievement of principals trained in a traditional principal preparation program and those trained in an alternate route principal preparation program within the same Mississippi university. Sixty-six Mississippi principals and assistant principals participated in the study. Of…

  7. Riccati transformations and principal solutions of discrete linear systems

    International Nuclear Information System (INIS)

    Ahlbrandt, C.D.; Hooker, J.W.

    1984-01-01

    Consider a second-order linear matrix difference equation. A definition of principal and anti-principal, or recessive and dominant, solutions of the equation are given and the existence of principal and anti-principal solutions and the essential uniqueness of principal solutions is proven

  8. Principals, Trust, and Cultivating Vibrant Schools

    Directory of Open Access Journals (Sweden)

    Megan Tschannen-Moran

    2015-03-01

    Full Text Available Although principals are ultimately held accountable to student learning in their buildings, the most consistent research results have suggested that their impact on student achievement is largely indirect. Leithwood, Patten, and Jantzi proposed four paths through which this indirect influence would flow, and the purpose of this special issue is to examine in greater depth these mediating variables. Among mediating variables, we assert that trust is key. In this paper, we explore the evidence that points to the role that faculty trust in the principal plays in student learning and how principals can cultivate trust by attending to the five facets of trust, as well as the correlates of trust that mediate student learning, including academic press, collective teacher efficacy, and teacher professionalism. We argue that trust plays a role in each of the four paths identified by Leithwood, Patten, and Jantzi. Finally, we explore possible new directions for future research.

  9. Principal component regression for crop yield estimation

    CERN Document Server

    Suryanarayana, T M V

    2016-01-01

    This book highlights the estimation of crop yield in Central Gujarat, especially with regard to the development of Multiple Regression Models and Principal Component Regression (PCR) models using climatological parameters as independent variables and crop yield as a dependent variable. It subsequently compares the multiple linear regression (MLR) and PCR results, and discusses the significance of PCR for crop yield estimation. In this context, the book also covers Principal Component Analysis (PCA), a statistical procedure used to reduce a number of correlated variables into a smaller number of uncorrelated variables called principal components (PC). This book will be helpful to the students and researchers, starting their works on climate and agriculture, mainly focussing on estimation models. The flow of chapters takes the readers in a smooth path, in understanding climate and weather and impact of climate change, and gradually proceeds towards downscaling techniques and then finally towards development of ...

  10. Geometry of Quantum Principal Bundles. Pt. 1

    International Nuclear Information System (INIS)

    Durdevic, M.

    1996-01-01

    A theory of principal bundles possessing quantum structure groups and classical base manifolds is presented. Structural analysis of such quantum principal bundles is performed. A differential calculus is constructed, combining differential forms on the base manifold with an appropriate differential calculus on the structure quantum group. Relations between the calculus on the group and the calculus on the bundle are investigated. A concept of (pseudo)tensoriality is formulated. The formalism of connections is developed. In particular, operators of horizontal projection, covariant derivative and curvature are constructed and analyzed. Generalizations of the first Structure Equation and of the Bianchi identity are found. Illustrative examples are presented. (orig.)

  11. Constrained principal component analysis and related techniques

    CERN Document Server

    Takane, Yoshio

    2013-01-01

    In multivariate data analysis, regression techniques predict one set of variables from another while principal component analysis (PCA) finds a subspace of minimal dimensionality that captures the largest variability in the data. How can regression analysis and PCA be combined in a beneficial way? Why and when is it a good idea to combine them? What kind of benefits are we getting from them? Addressing these questions, Constrained Principal Component Analysis and Related Techniques shows how constrained PCA (CPCA) offers a unified framework for these approaches.The book begins with four concre

  12. From soil in art towards Soil Art

    Science.gov (United States)

    Feller, C.; Landa, E. R.; Toland, A.; Wessolek, G.

    2015-02-01

    The range of art forms and genres dealing with soil is wide and diverse, spanning many centuries and artistic traditions, from prehistoric painting and ceramics to early Renaissance works in Western literature, poetry, paintings, and sculpture, to recent developments in cinema, architecture and contemporary art. Case studies focused on painting, installation, and cinema are presented with the view of encouraging further exploration of art about, in, with, or featuring soil or soil conservation issues, created by artists, and occasionally scientists, educators or collaborative efforts thereof.

  13. Ecological and health risk-based characterization of agricultural soils contaminated with polycyclic aromatic hydrocarbons in the vicinity of a chemical plant in China.

    Science.gov (United States)

    Liu, Geng; Niu, Junjie; Guo, Wenjiong; An, Xiangsheng; Zhao, Long

    2016-11-01

    Polycyclic aromatic hydrocarbons (PAHs) from chemical plants can cause serious pollution of surrounding agricultural soils. A comprehensive study of agricultural soils was conducted in the vicinity of a chemical plant in China to characterize the soil PAH concentration, as well as their composition and sources. Human health and a screening-level ecological risk assessment were conducted for PAH contamination in agricultural soils. The results showed that the total concentrations of 16 priority PAHs ranged from 250.49 to 9387.26 ng g(-1), with an average of 2780.42 ng g(-1). High molecular weight PAHs (four to six rings) were the dominant component, accounting for more than 60% of all PAHs. Principal component analysis (PCA) and positive matrix factorization model (PMF) suggested that diesel emissions, coal combustion, coke ovens, and fuel combustion and gasoline emissions were the main sources of PAHs in agricultural soils. The ecological risk assessment results based on the effects range-low (ERL), the effects range-median (ERM), and the ecological screening levels (ESL) indicated that the exposure to ∑PAH16 was >ERL, >ERM, and ≥ERL and ESL at 78.1% of the soil sampling stations, and could induce biological effects in mammals. The Bapeq concentrations posed a potential carcinogenic risk to humans. Further risk management and control of soil PAHs in these agricultural soils is required to ensure the safety of the biocoenosis and human health. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. The Deputy Principal Instructional Leadership Role and Professional Learning: Perceptions of Secondary Principals, Deputies and Teachers

    Science.gov (United States)

    Leaf, Ann; Odhiambo, George

    2017-01-01

    Purpose: The purpose of this paper is to report on a study examining the perceptions of secondary principals, deputies and teachers, of deputy principal (DP) instructional leadership (IL), as well as deputies' professional learning (PL) needs. Framed within an interpretivist approach, the specific objectives of this study were: to explore the…

  15. Statewide Data on Supply and Demand of Principals after Policy Changes to Principal Preparation in Illinois

    Science.gov (United States)

    Haller, Alicia; Hunt, Erika

    2016-01-01

    Research has demonstrated that principals have a powerful impact on school improvement and student learning. Principals play a vital role in recruiting, developing, and retaining effective teachers; creating a school-wide culture of learning; and implementing a continuous improvement plan aimed at increasing student achievement. Leithwood, Louis,…

  16. Principal Self-Efficacy, Teacher Perceptions of Principal Performance, and Teacher Job Satisfaction

    Science.gov (United States)

    Evans, Molly Lynn

    2016-01-01

    In public schools, the principal's role is of paramount importance in influencing teachers to excel and to keep their job satisfaction high. The self-efficacy of leaders is an important characteristic of leadership, but this issue has not been extensively explored in school principals. Using internet-based questionnaires, this study obtained…

  17. Andragogical Practices of School Principals in Developing the Leadership Capacities of Assistant Principals

    Science.gov (United States)

    McDaniel, Luther

    2017-01-01

    The purpose of this mixed methods study was to assess school principals' perspectives of the extent to which they apply the principles of andragogy to the professional development of assistant principals in their schools. This study was conducted in school districts that constitute a RESA area in a southeastern state. The schools in these…

  18. What Principals Should Know About Food Allergies.

    Science.gov (United States)

    Munoz-Furlong, Anne

    2002-01-01

    Describes what principals should know about recent research findings on food allergies (peanuts, tree nuts, milk, eggs, soy, wheat) that can produce severe or life-threatening reactions in children. Asserts that every school should have trained staff and written procedures for reacting quickly to allergic reactions. (PKP)

  19. A Principal's Guide to Children's Allergies.

    Science.gov (United States)

    Munoz-Furlong, Anne

    1999-01-01

    Discusses several common children's allergies, including allergic rhinitis, asthma, atopic dermatitis, food allergies, and anaphylactic shock. Principals should become familiar with various medications and should work with children's parents and physicians to determine how to manage their allergies at school. Allergen avoidance is the best…

  20. Assessment of School Principals' Reassignment Process

    Science.gov (United States)

    Sezgin-Nartgün, Senay; Ekinci, Serkan

    2016-01-01

    This study aimed to identify administrators' views related to the assessment of school principals' reassignment in educational organizations. The study utilized qualitative research design and the study group composed of 8 school administrators selected via simple sampling who were employed in the Bolu central district in 2014-2015 academic year.…

  1. An Exploration of Principal Instructional Technology Leadership

    Science.gov (United States)

    Townsend, LaTricia Walker

    2013-01-01

    Nationwide the demand for schools to incorporate technology into their educational programs is great. In response, North Carolina developed the IMPACT model in 2003 to provide a comprehensive model for technology integration in the state. The model is aligned to national educational technology standards for teachers, students, and principals.…

  2. Principals' Leadership Styles and Student Achievement

    Science.gov (United States)

    Harnish, David Alan

    2012-01-01

    Many schools struggle to meet No Child Left Behind's stringent adequate yearly progress standards, although the benchmark has stimulated national creativity and reform. The purpose of this study was to explore teacher perceptions of principals' leadership styles, curriculum reform, and student achievement to ascertain possible factors to improve…

  3. How To Select a Good Assistant Principal.

    Science.gov (United States)

    Holman, Linda J.

    1997-01-01

    Notes that a well-structured job profile and interview can provide insight into the key qualities of an effective assistant principal. These include organizational skills, basic accounting knowledge, interpersonal skills, dependability, strong work ethic, effective problem-solving skills, leadership skills, written communication skills,…

  4. Principals' Transformational Leadership in School Improvement

    Science.gov (United States)

    Yang, Yingxiu

    2013-01-01

    Purpose: This paper aims to contribute experience and ideas of the transformational leadership, not only for the principal want to improve leadership himself (herself), but also for the school at critical period of improvement, through summarizing forming process and the problem during the course and key factors that affect the course.…

  5. Imprecise Beliefs in a Principal Agent Model

    NARCIS (Netherlands)

    Rigotti, L.

    1998-01-01

    This paper presents a principal-agent model where the agent has multiple, or imprecise, beliefs. We model this situation formally by assuming the agent's preferences are incomplete. One can interpret this multiplicity as an agent's limited knowledge of the surrounding environment. In this setting,

  6. Bootstrap confidence intervals for principal response curves

    NARCIS (Netherlands)

    Timmerman, Marieke E.; Ter Braak, Cajo J. F.

    2008-01-01

    The principal response curve (PRC) model is of use to analyse multivariate data resulting from experiments involving repeated sampling in time. The time-dependent treatment effects are represented by PRCs, which are functional in nature. The sample PRCs can be estimated using a raw approach, or the

  7. Bootstrap Confidence Intervals for Principal Response Curves

    NARCIS (Netherlands)

    Timmerman, M.E.; Braak, ter C.J.F.

    2008-01-01

    The principal response curve (PRC) model is of use to analyse multivariate data resulting from experiments involving repeated sampling in time. The time-dependent treatment effects are represented by PRCs, which are functional in nature. The sample PRCs can be estimated using a raw approach, or the

  8. Islamitisch financieren tussen principes en realiteit

    NARCIS (Netherlands)

    Wolters, W.G.

    2009-01-01

    ‘De financiële crisis zou niet hebben plaatsgevonden, als de wereld de principes van islamitisch bankieren en financieren zou hebben aangenomen.’ Dat was één van de kenmerkende reacties van de kant van de islamitische bankiers, in de laatste maanden van 2008. Toen begon de wereldwijde financiële

  9. Dealing with Crises: One Principal's Experience.

    Science.gov (United States)

    Foley, Charles F.

    1986-01-01

    The principal of Concord High School (New Hampshire) recounts the 1985-86 school year's four crises--the visits of teacher-astronaut Christa McAuliffe and Secretary of Education William Bennett, the shooting of a former student, and the Challenger space shuttle explosion. The greatest challenge was resuming the normal schedule and fielding media…

  10. Principal Pressure in the Middle of Accountability

    Science.gov (United States)

    Derrington, Mary Lynne; Larsen, Donald E.

    2012-01-01

    When a new superintendent is hired, Tom Thompson, middle school principal, is squeezed between complying with the demands of the district and cultivating a positive culture in his school. He wrestles with the stress of facing tough leadership choices that take a toll on his physical and mental health. Tom realizes that a career-ending move might…

  11. The Relationship between Principals' Managerial Approaches and ...

    African Journals Online (AJOL)

    Students' discipline is critical to the attainment of positive school outcomes. This paper presents and discusses findings of a study on the relationship between principals' management approaches and the level of student discipline in selected public secondary schools in Kenya. The premise of the study was that the level of ...

  12. Primary School Principals' Experiences with Smartphone Apps

    Science.gov (United States)

    Çakir, Rahman; Aktay, Sayim

    2016-01-01

    Smartphones are not just pieces of hardware, they at same time also dip into software features such as communication systems. The aim of this study is to examine primary school principals' experiences with smart phone applications. Shedding light on this subject means that this research is qualitative. Criterion sampling has been intentionally…

  13. Principal normal indicatrices of closed space curves

    DEFF Research Database (Denmark)

    Røgen, Peter

    1999-01-01

    A theorem due to J. Weiner, which is also proven by B. Solomon, implies that a principal normal indicatrix of a closed space curve with nonvanishing curvature has integrated geodesic curvature zero and contains no subarc with integrated geodesic curvature pi. We prove that the inverse problem alw...

  14. Summer Principals'/Directors' Orientation Training Module.

    Science.gov (United States)

    Mata, Robert L.; Garcia, Richard L.

    Intended to provide current or potential project principals/directors with the basic knowledge, skills, abilities, and sensitivities needed to manage a summer migrant school project in the local educational setting, this module provides instruction in the project management areas of planning, preparation, control, and termination. The module…

  15. Probabilistic Principal Component Analysis for Metabolomic Data.

    LENUS (Irish Health Repository)

    Nyamundanda, Gift

    2010-11-23

    Abstract Background Data from metabolomic studies are typically complex and high-dimensional. Principal component analysis (PCA) is currently the most widely used statistical technique for analyzing metabolomic data. However, PCA is limited by the fact that it is not based on a statistical model. Results Here, probabilistic principal component analysis (PPCA) which addresses some of the limitations of PCA, is reviewed and extended. A novel extension of PPCA, called probabilistic principal component and covariates analysis (PPCCA), is introduced which provides a flexible approach to jointly model metabolomic data and additional covariate information. The use of a mixture of PPCA models for discovering the number of inherent groups in metabolomic data is demonstrated. The jackknife technique is employed to construct confidence intervals for estimated model parameters throughout. The optimal number of principal components is determined through the use of the Bayesian Information Criterion model selection tool, which is modified to address the high dimensionality of the data. Conclusions The methods presented are illustrated through an application to metabolomic data sets. Jointly modeling metabolomic data and covariates was successfully achieved and has the potential to provide deeper insight to the underlying data structure. Examination of confidence intervals for the model parameters, such as loadings, allows for principled and clear interpretation of the underlying data structure. A software package called MetabolAnalyze, freely available through the R statistical software, has been developed to facilitate implementation of the presented methods in the metabolomics field.

  16. Principals in Partnership with Math Coaches

    Science.gov (United States)

    Grant, Catherine Miles; Davenport, Linda Ruiz

    2009-01-01

    One of the most promising developments in math education is the fact that many districts are hiring math coaches--also called math resource teachers, math facilitators, math lead teachers, or math specialists--to assist elementary-level teachers with math instruction. What must not be lost, however, is that principals play an essential role in…

  17. Experimental and principal component analysis of waste ...

    African Journals Online (AJOL)

    The present study is aimed at determining through principal component analysis the most important variables affecting bacterial degradation in ponds. Data were collected from literature. In addition, samples were also collected from the waste stabilization ponds at the University of Nigeria, Nsukka and analyzed to ...

  18. Principal Component Analysis as an Efficient Performance ...

    African Journals Online (AJOL)

    This paper uses the principal component analysis (PCA) to examine the possibility of using few explanatory variables (X's) to explain the variation in Y. It applied PCA to assess the performance of students in Abia State Polytechnic, Aba, Nigeria. This was done by estimating the coefficients of eight explanatory variables in a ...

  19. Principal component analysis of psoriasis lesions images

    DEFF Research Database (Denmark)

    Maletti, Gabriela Mariel; Ersbøll, Bjarne Kjær

    2003-01-01

    A set of RGB images of psoriasis lesions is used. By visual examination of these images, there seem to be no common pattern that could be used to find and align the lesions within and between sessions. It is expected that the principal components of the original images could be useful during future...

  20. The Principal as Professional Development Leader

    Science.gov (United States)

    Lindstrom, Phyllis H.; Speck, Marsha

    2004-01-01

    Individual teachers have the greatest effect on student performance. Principals, as professional development leaders, are in the best position to provide teachers with the professional development strategies they need to improve skills and raise student achievement. This book guides readers through a step-by-step process to formulate, implement,…

  1. Burnout And Lifestyle Of Principals And Entrepreneurs

    Directory of Open Access Journals (Sweden)

    Jasna Lavrenčič

    2014-12-01

    Full Text Available Research Question (RQ: What kind of lifestyle do the principals and entrepreneurs lead? Does the lifestyle of principals and entrepreneurs influence burnout? Purpose: To find out, based on the results of a questionnaire, what kind of lifestyle both researched groups lead. Does lifestyle have an influence on the occurrence of the phenomenon of burnout. Method: We used the method of data collection by questionnaire. Acquired data were analyzed using SPSS, descriptive and inference statistics. Results: Results showed, that both groups lead a similar lifestyle and that lifestyle influences burnout with principals, as well as entrepreneurs. Organization: School principals and entrepreneurs are the heads of individual organizations or companies, the goal of which is success. To be successful in their work, they must adapt their lifestyle, which can be healthy or unhealthy. If their lifestyle is unhealthy, it can lead to burnout. Society: With results of the questionnaire we would like to answer the question about the lifestyle of both groups and its influence on the occurrence of burnout. Originality: The study of lifestyle and the occurrence of burnout in these two groups is the first study in this area. Limitations/Future Research: In continuation, research groups could be submitted to the research fields of effort physiology and tracking of certain haematological parameters, such as cholesterol, blood sugar and stress hormones - adrenaline, noradrenalin, cortisol. Thus, we could carry out an even more in depth research of the connection between lifestyle and burnout.

  2. Principal Connection / Amazon and the Whole Teacher

    Science.gov (United States)

    Hoerr, Thomas R.

    2015-01-01

    A recent controversy over Amazon's culture has strong implications for the whole child approach, and it offers powerful lessons for principals. A significant difference between the culture of so many businesses today and the culture at good schools is that in good schools, the welfare of the employees is very important. Student success is the…

  3. The Gender of Secondary School Principals.

    Science.gov (United States)

    Bonuso, Carl; Shakeshaft, Charol

    1983-01-01

    A study was conducted to understand why so few of the secondary school principals in New York State are women. Results suggest two possible causes: either sufficient women candidates do not apply for the positions, or sex discrimination still exists. (KH)

  4. Dynamic verification of newton's law and the principal limits in measuring intermediate-range forces

    International Nuclear Information System (INIS)

    Kolosnitsyn, N.I.; Luo Jun; Melnikov, V.N.

    1992-01-01

    According to the controversial results of recent experiments for fifth force, a classification of all possible types of theories leading to non-Newtonian forces is presented. The theoretical analysis shows that if the interaction potential differs from the Newton's law the interactions of macro-and micro-bodies are in general distinguishable. The calculation also shows that Long's result can be improved by several orders if the new method proposed is used

  5. Extraction of Independent Structural Images for Principal Component Thermography

    Directory of Open Access Journals (Sweden)

    Dmitry Gavrilov

    2018-03-01

    Full Text Available Thermography is a powerful tool for non-destructive testing of a wide range of materials. Thermography has a number of approaches differing in both experiment setup and the way the collected data are processed. Among such approaches is the Principal Component Thermography (PCT method, which is based on the statistical processing of raw thermal images collected by thermal camera. The processed images (principal components or empirical orthogonal functions form an orthonormal basis, and often look like a superposition of all possible structural features found in the object under inspection—i.e., surface heating non-uniformity, internal defects and material structure. At the same time, from practical point of view it is desirable to have images representing independent structural features. The work presented in this paper proposes an approach for separation of independent image patterns (archetypes from a set of principal component images. The approach is demonstrated in the application of inspection of composite materials as well as the non-invasive analysis of works of art.

  6. Soil algae

    African Journals Online (AJOL)

    Timothy Ademakinwa

    Also, the importance of algae in soil formation and soil fertility improvement cannot be over ... The presence of nitrogen fixing microalgae (Nostoc azollae) in the top soil of both vegetable ..... dung, fish food and dirty water from fish ponds on.

  7. Pedoinformatics Approach to Soil Text Analytics

    Science.gov (United States)

    Furey, J.; Seiter, J.; Davis, A.

    2017-12-01

    The several extant schema for the classification of soils rely on differing criteria, but the major soil science taxonomies, including the United States Department of Agriculture (USDA) and the international harmonized World Reference Base for Soil Resources systems, are based principally on inferred pedogenic properties. These taxonomies largely result from compiled individual observations of soil morphologies within soil profiles, and the vast majority of this pedologic information is contained in qualitative text descriptions. We present text mining analyses of hundreds of gigabytes of parsed text and other data in the digitally available USDA soil taxonomy documentation, the Soil Survey Geographic (SSURGO) database, and the National Cooperative Soil Survey (NCSS) soil characterization database. These analyses implemented iPython calls to Gensim modules for topic modelling, with latent semantic indexing completed down to the lowest taxon level (soil series) paragraphs. Via a custom extension of the Natural Language Toolkit (NLTK), approximately one percent of the USDA soil series descriptions were used to train a classifier for the remainder of the documents, essentially by treating soil science words as comprising a novel language. While location-specific descriptors at the soil series level are amenable to geomatics methods, unsupervised clustering of the occurrence of other soil science words did not closely follow the usual hierarchy of soil taxa. We present preliminary phrasal analyses that may account for some of these effects.

  8. Palm-vein classification based on principal orientation features.

    Directory of Open Access Journals (Sweden)

    Yujia Zhou

    Full Text Available Personal recognition using palm-vein patterns has emerged as a promising alternative for human recognition because of its uniqueness, stability, live body identification, flexibility, and difficulty to cheat. With the expanding application of palm-vein pattern recognition, the corresponding growth of the database has resulted in a long response time. To shorten the response time of identification, this paper proposes a simple and useful classification for palm-vein identification based on principal direction features. In the registration process, the Gaussian-Radon transform is adopted to extract the orientation matrix and then compute the principal direction of a palm-vein image based on the orientation matrix. The database can be classified into six bins based on the value of the principal direction. In the identification process, the principal direction of the test sample is first extracted to ascertain the corresponding bin. One-by-one matching with the training samples is then performed in the bin. To improve recognition efficiency while maintaining better recognition accuracy, two neighborhood bins of the corresponding bin are continuously searched to identify the input palm-vein image. Evaluation experiments are conducted on three different databases, namely, PolyU, CASIA, and the database of this study. Experimental results show that the searching range of one test sample in PolyU, CASIA and our database by the proposed method for palm-vein identification can be reduced to 14.29%, 14.50%, and 14.28%, with retrieval accuracy of 96.67%, 96.00%, and 97.71%, respectively. With 10,000 training samples in the database, the execution time of the identification process by the traditional method is 18.56 s, while that by the proposed approach is 3.16 s. The experimental results confirm that the proposed approach is more efficient than the traditional method, especially for a large database.

  9. Developing and using artificial soils to analyze soil microbial processes

    Science.gov (United States)

    Gao, X.; Cheng, H. Y.; Boynton, L.; Masiello, C. A.; Silberg, J. J.

    2017-12-01

    Microbial diversity and function in soils are governed by soil characteristics such as mineral composition, particles size and aggregations, soil organic matter (SOM), and availability of nutrients and H2O. The spatial and temporal heterogeneity of soils creates a range of niches (hotspots) differing in the availability of O2, H2O, and nutrients, which shapes microbial activities at scales ranging from nanometer to landscape. Synthetic biologists often examine microbial response trigged by their environment conditions in nutrient-rich aqueous media using single strain microbes. While these studies provided useful insight in the role of soil microbes in important soil biogeochemical processes (e.g., C cycling, N cycling, etc.), the results obtained from the over-simplified model systems are often not applicable natural soil systems. On the contrary, soil microbiologists examine microbial processes in natural soils using longer incubation time. However, due to its physical, chemical and biological complexity of natural soils, it is often difficult to examine soil characteristics independently and understand how each characteristic influences soil microbial activities and their corresponding soil functioning. Therefore, it is necessary to bridge the gap and develop a model matrix to exclude unpredictable influences from the environment while still reliably mimicking real environmental conditions. The objective of this study is to design a range of ecologically-relevant artificial soils with varying texture (particle size distribution), structure, mineralogy, SOM content, and nutrient heterogeneity. We thoroughly characterize the artificial soils for pH, active surface area and surface morphology, cation exchange capacity (CEC), and water retention curve. We demonstrate the effectiveness of the artificial soils as useful matrix for microbial processes, such as microbial growth and horizontal gene transfer (HGT), using the gas-reporting biosensors recently developed in

  10. Integrated GIS and multivariate statistical analysis for regional scale assessment of heavy metal soil contamination: A critical review.

    Science.gov (United States)

    Hou, Deyi; O'Connor, David; Nathanail, Paul; Tian, Li; Ma, Yan

    2017-12-01

    Heavy metal soil contamination is associated with potential toxicity to humans or ecotoxicity. Scholars have increasingly used a combination of geographical information science (GIS) with geostatistical and multivariate statistical analysis techniques to examine the spatial distribution of heavy metals in soils at a regional scale. A review of such studies showed that most soil sampling programs were based on grid patterns and composite sampling methodologies. Many programs intended to characterize various soil types and land use types. The most often used sampling depth intervals were 0-0.10 m, or 0-0.20 m, below surface; and the sampling densities used ranged from 0.0004 to 6.1 samples per km 2 , with a median of 0.4 samples per km 2 . The most widely used spatial interpolators were inverse distance weighted interpolation and ordinary kriging; and the most often used multivariate statistical analysis techniques were principal component analysis and cluster analysis. The review also identified several determining and correlating factors in heavy metal distribution in soils, including soil type, soil pH, soil organic matter, land use type, Fe, Al, and heavy metal concentrations. The major natural and anthropogenic sources of heavy metals were found to derive from lithogenic origin, roadway and transportation, atmospheric deposition, wastewater and runoff from industrial and mining facilities, fertilizer application, livestock manure, and sewage sludge. This review argues that the full potential of integrated GIS and multivariate statistical analysis for assessing heavy metal distribution in soils on a regional scale has not yet been fully realized. It is proposed that future research be conducted to map multivariate results in GIS to pinpoint specific anthropogenic sources, to analyze temporal trends in addition to spatial patterns, to optimize modeling parameters, and to expand the use of different multivariate analysis tools beyond principal component analysis

  11. Principal components analysis in clinical studies.

    Science.gov (United States)

    Zhang, Zhongheng; Castelló, Adela

    2017-09-01

    In multivariate analysis, independent variables are usually correlated to each other which can introduce multicollinearity in the regression models. One approach to solve this problem is to apply principal components analysis (PCA) over these variables. This method uses orthogonal transformation to represent sets of potentially correlated variables with principal components (PC) that are linearly uncorrelated. PCs are ordered so that the first PC has the largest possible variance and only some components are selected to represent the correlated variables. As a result, the dimension of the variable space is reduced. This tutorial illustrates how to perform PCA in R environment, the example is a simulated dataset in which two PCs are responsible for the majority of the variance in the data. Furthermore, the visualization of PCA is highlighted.

  12. A Genealogical Interpretation of Principal Components Analysis

    Science.gov (United States)

    McVean, Gil

    2009-01-01

    Principal components analysis, PCA, is a statistical method commonly used in population genetics to identify structure in the distribution of genetic variation across geographical location and ethnic background. However, while the method is often used to inform about historical demographic processes, little is known about the relationship between fundamental demographic parameters and the projection of samples onto the primary axes. Here I show that for SNP data the projection of samples onto the principal components can be obtained directly from considering the average coalescent times between pairs of haploid genomes. The result provides a framework for interpreting PCA projections in terms of underlying processes, including migration, geographical isolation, and admixture. I also demonstrate a link between PCA and Wright's fst and show that SNP ascertainment has a largely simple and predictable effect on the projection of samples. Using examples from human genetics, I discuss the application of these results to empirical data and the implications for inference. PMID:19834557

  13. PCA: Principal Component Analysis for spectra modeling

    Science.gov (United States)

    Hurley, Peter D.; Oliver, Seb; Farrah, Duncan; Wang, Lingyu; Efstathiou, Andreas

    2012-07-01

    The mid-infrared spectra of ultraluminous infrared galaxies (ULIRGs) contain a variety of spectral features that can be used as diagnostics to characterize the spectra. However, such diagnostics are biased by our prior prejudices on the origin of the features. Moreover, by using only part of the spectrum they do not utilize the full information content of the spectra. Blind statistical techniques such as principal component analysis (PCA) consider the whole spectrum, find correlated features and separate them out into distinct components. This code, written in IDL, classifies principal components of IRS spectra to define a new classification scheme using 5D Gaussian mixtures modelling. The five PCs and average spectra for the four classifications to classify objects are made available with the code.

  14. COPD phenotype description using principal components analysis

    DEFF Research Database (Denmark)

    Roy, Kay; Smith, Jacky; Kolsum, Umme

    2009-01-01

    BACKGROUND: Airway inflammation in COPD can be measured using biomarkers such as induced sputum and Fe(NO). This study set out to explore the heterogeneity of COPD using biomarkers of airway and systemic inflammation and pulmonary function by principal components analysis (PCA). SUBJECTS...... AND METHODS: In 127 COPD patients (mean FEV1 61%), pulmonary function, Fe(NO), plasma CRP and TNF-alpha, sputum differential cell counts and sputum IL8 (pg/ml) were measured. Principal components analysis as well as multivariate analysis was performed. RESULTS: PCA identified four main components (% variance...... associations between the variables within components 1 and 2. CONCLUSION: COPD is a multi dimensional disease. Unrelated components of disease were identified, including neutrophilic airway inflammation which was associated with systemic inflammation, and sputum eosinophils which were related to increased Fe...

  15. Environmental risk of heavy metal pollution and contamination sources using multivariate analysis in the soils of Varanasi environs, India.

    Science.gov (United States)

    Singh, Shubhra; Raju, N Janardhana; Nazneen, Sadaf

    2015-06-01

    This study assessed soil pollution in the Varanasi environs of Uttar Pradesh in India. Assessing the concentration of potentially harmful heavy metals in the soils is imperative in order to evaluate the potential risks to human. To identify the concentration and sources of heavy metals and assess the soil environmental quality, 23 samples were collected from different locations covering dumping, road and agricultural area. The average concentrations of the heavy metals were all below the permissible limits according to soil quality guidelines except Cu (copper) and Pb (lead) in dumping and road soils. Soil heavy metal contamination was assessed on the basis of geoaccumulation index (Igeo), pollution index (PI) and integrated pollution index (IPI). The IPI of the metals ranged from 0.59 to 9.94, with the highest IPI observed in the dumping and road soils. A very significant correlation was found between Pb and Cu. The result of principal component analysis suggested that PC1 was mainly affected by the use of agrochemicals, PC2 was affected by vehicular emission and PC3 was affected by dumping waste. Meanwhile, PC4 was mainly controlled by parent material along with anthropogenic activities. Appropriate measures should be taken to minimize the heavy metal levels in soils and thus protect human health.

  16. Diversities of phthalate esters in suburban agricultural soils and wasteland soil appeared with urbanization in China

    International Nuclear Information System (INIS)

    Kong Shaofei; Ji Yaqin; Liu Lingling; Chen Li; Zhao Xueyan; Wang Jiajun; Bai Zhipeng; Sun Zengrong

    2012-01-01

    The distribution of six priority phthalic acid esters (PAEs) in suburban farmland, vegetable, orchard and wasteland soils of Tianjin were obtained with gas chromatography-mass spectrometer analysis in 2009. Results showed that total PAEs varied from 0.05 to 10.4 μg g −1 , with the median value as 0.32 μg g −1 . Di-(2-ethylhexyl) phthalate and di-n-butyl phthalate are most abundant species. PAEs concentrations for the four types of soils exhibited decreasing order as vegetable soil > wasteland soil > farmland soil > orchard soil. PAEs exhibited elevated levels in more developed regions when compared with other studies. The agricultural plastic film could elevate the PAEs contents in soils. Principal component analysis indicated the emission from cosmetics and personal care products and plasticizers were important sources for PAEs in suburban soils in Tianjin. The higher PAEs contents in wasteland soils from suburban area should be paid more attention owing to large amounts of solid wastes appeared with the ongoing urbanization. - Highlights: ► PAEs levels in four types of soils in suburban area of Tianjin were studied. ► Vegetable soil and wasteland soil exhibited higher PAEs concentrations. ► PAEs in wasteland soils from suburban area of cities in China should be paid attention. - (1) Vegetable soil and wasteland soil exhibited higher PAEs concentrations; (2) PAEs in wasteland soils from suburban area of cities in China should be paid attention.

  17. Executive Compensation and Principal-Agent Theory.

    OpenAIRE

    Garen, John E

    1994-01-01

    The empirical literature on executive compensation generally fails to specify a model of executive pay on which to base hypotheses regarding its determinants. In contrast, this paper analyzes a simple principal-agent model to determine how well it explains variations in CEO incentive pay and salaries. Many findings are consistent with the basic intuition of principle-agent models that compensation is structured to trade off incentives with insurance. However, statistical significance for some...

  18. Resonant Homoclinic Flips Bifurcation in Principal Eigendirections

    Directory of Open Access Journals (Sweden)

    Tiansi Zhang

    2013-01-01

    Full Text Available A codimension-4 homoclinic bifurcation with one orbit flip and one inclination flip at principal eigenvalue direction resonance is considered. By introducing a local active coordinate system in some small neighborhood of homoclinic orbit, we get the Poincaré return map and the bifurcation equation. A detailed investigation produces the number and the existence of 1-homoclinic orbit, 1-periodic orbit, and double 1-periodic orbits. We also locate their bifurcation surfaces in certain regions.

  19. Principal bundles on the projective line

    Indian Academy of Sciences (India)

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

    LetX be a complete nonsingular curve over the algebraic closurek ofk andGa reductive group over k. Let E → X be a principal G-bundle on X. E is said to be semistable if, for every reduction of structure group EP ⊂ E to a maximal parabolic subgroup P of G, we have degree EP (p) ≤ 0, where p is the Lie algebra of P and EP ...

  20. Interplay between tilted and principal axis rotation

    International Nuclear Information System (INIS)

    Datta, Pradip; Roy, Santosh; Chattopadhyay, S.

    2014-01-01

    At IUAC-INGA, our group has studied four neutron rich nuclei of mass-110 region, namely 109,110 Ag and 108,110 Cd. These nuclei provide the unique platform to study the interplay between Tilted and Principal axis rotation since these are moderately deformed and at the same time, shears structures are present at higher spins. The salient features of the high spin behaviors of these nuclei will be discussed which are the signatures of this interplay

  1. Interplay between tilted and principal axis rotation

    Energy Technology Data Exchange (ETDEWEB)

    Datta, Pradip [Ananda Mohan College, 102/1 Raja Rammohan Sarani, Kolkata 700 009 (India); Roy, Santosh; Chattopadhyay, S. [Saha Institute of Nuclear Physics, 1/AF Bidhan Nagar, Kolkata 700 064 (India)

    2014-08-14

    At IUAC-INGA, our group has studied four neutron rich nuclei of mass-110 region, namely {sup 109,110}Ag and {sup 108,110}Cd. These nuclei provide the unique platform to study the interplay between Tilted and Principal axis rotation since these are moderately deformed and at the same time, shears structures are present at higher spins. The salient features of the high spin behaviors of these nuclei will be discussed which are the signatures of this interplay.

  2. Multilevel sparse functional principal component analysis.

    Science.gov (United States)

    Di, Chongzhi; Crainiceanu, Ciprian M; Jank, Wolfgang S

    2014-01-29

    We consider analysis of sparsely sampled multilevel functional data, where the basic observational unit is a function and data have a natural hierarchy of basic units. An example is when functions are recorded at multiple visits for each subject. Multilevel functional principal component analysis (MFPCA; Di et al. 2009) was proposed for such data when functions are densely recorded. Here we consider the case when functions are sparsely sampled and may contain only a few observations per function. We exploit the multilevel structure of covariance operators and achieve data reduction by principal component decompositions at both between and within subject levels. We address inherent methodological differences in the sparse sampling context to: 1) estimate the covariance operators; 2) estimate the functional principal component scores; 3) predict the underlying curves. Through simulations the proposed method is able to discover dominating modes of variations and reconstruct underlying curves well even in sparse settings. Our approach is illustrated by two applications, the Sleep Heart Health Study and eBay auctions.

  3. A principal components model of soundscape perception.

    Science.gov (United States)

    Axelsson, Östen; Nilsson, Mats E; Berglund, Birgitta

    2010-11-01

    There is a need for a model that identifies underlying dimensions of soundscape perception, and which may guide measurement and improvement of soundscape quality. With the purpose to develop such a model, a listening experiment was conducted. One hundred listeners measured 50 excerpts of binaural recordings of urban outdoor soundscapes on 116 attribute scales. The average attribute scale values were subjected to principal components analysis, resulting in three components: Pleasantness, eventfulness, and familiarity, explaining 50, 18 and 6% of the total variance, respectively. The principal-component scores were correlated with physical soundscape properties, including categories of dominant sounds and acoustic variables. Soundscape excerpts dominated by technological sounds were found to be unpleasant, whereas soundscape excerpts dominated by natural sounds were pleasant, and soundscape excerpts dominated by human sounds were eventful. These relationships remained after controlling for the overall soundscape loudness (Zwicker's N(10)), which shows that 'informational' properties are substantial contributors to the perception of soundscape. The proposed principal components model provides a framework for future soundscape research and practice. In particular, it suggests which basic dimensions are necessary to measure, how to measure them by a defined set of attribute scales, and how to promote high-quality soundscapes.

  4. Concentrations of polychlorinated biphenyls in soil and indoor dust associated with electricity generation facilities in Lagos, Nigeria.

    Science.gov (United States)

    Folarin, Bilikis Temitope; Abdallah, Mohamed Abou-Elwafa; Oluseyi, Temilola; Olayinka, Kehinde; Harrad, Stuart

    2018-09-01

    Concentrations of 7 indicator polychlorinated biphenyls (PCBs) were measured in dust and soil samples from 12 power stations collected over the two major seasons of the Nigerian climate. Median ƩPCB 7 concentrations in soil ranged from 2 ng/g for power station A to 220 ng/g for power station I; while those in dust ranged from 21 ng/g for power station L to 2200 ng/g for power station I. For individual congeners, median PCB concentrations ranged from 3.8 ng/g for PCB 101 to 52 ng/g for PCB 180 in dust, and  transmission > distribution). Congener patterns in dust and soil samples were compared using principal component analysis (PCA) with those in transformer oil samples from 3 of the power stations studied and with common PCB mixtures (Aroclors). This revealed congener patterns in soil were more closely related to that in the transformer oil than dust. Congener patterns in most samples were similar to Aroclor 1260. Concentrations of PCBs in soil samples close to the transformers significantly exceeded those in soil sampled further away. Copyright © 2018 Elsevier Ltd. All rights reserved.

  5. Soil physics and the water management of spatially variable soils

    International Nuclear Information System (INIS)

    Youngs, E.G.

    1983-01-01

    The physics of macroscopic soil-water behaviour in inert porous materials has been developed by considering water flow to take place in a continuum. This requires the flow region to consist of an assembly of representative elementary volumes, repeated throughout space and small compared with the scale of observations. Soil-water behaviour in swelling soils may also be considered as a continuum phenomenon so long as the soil is saturated and swells and shrinks in the normal range. Macroscale heterogeneity superimposed on the inherent microscale heterogeneity can take many forms and may pose difficulties in the definition and measurement of soil physical properties and also in the development and use of predictive theories of soil-water behaviour. Thus, measurement techniques appropriate for uniform soils are often inappropriate, and criteria for soil-water management, obtained from theoretical considerations of behaviour in equivalent uniform soils, are not applicable without modification when there is soil heterogeneity. The spatial variability of soil-water properties is shown in results from field experiments concerned with water flow measurements; these illustrate both stochastic and deterministic heterogeneity in soil-water properties. Problems of water management of spatially variable soils when there is stochastic heterogeneity appear to present an insuperable problem in the application of theory. However, for soils showing deterministic heterogeneity, soil-water theory has been used in the solution of soil-water management problems. Thus, scaling using similar media theory has been applied to the infiltration of water into soils that vary over a catchment area. Also, the drain spacing to control the water-table height in soils in which the hydraulic conductivity varies with depth has been calculated using groundwater seepage theory. (author)

  6. The Interdependence of Principal School Leadership and Student Achievement

    Science.gov (United States)

    Soehner, David; Ryan, Thomas

    2011-01-01

    This review illuminated principal school leadership as a variable that impacted achievement. The principal as school leader and manager was explored because these roles were thought to impact student achievement both directly and indirectly. Specific principal leadership behaviors and principal effectiveness were explored as variables potentially…

  7. Negligence--When Is the Principal Liable? A Legal Memorandum.

    Science.gov (United States)

    Stern, Ralph D., Ed.

    Negligence, a tort liability, is defined, discussed, and reviewed in relation to several court decisions involving school principals. The history of liability suits against school principals suggests that a reasonable, prudent principal can avoid legal problems. Ten guidelines are presented to assist principals in avoiding charges of negligence.…

  8. Management Of Indiscipline Among Teachers By Principals Of ...

    African Journals Online (AJOL)

    This study compared the management of indiscipline among teachers by public and private school principals in Akwa Ibom State. The sample comprised four hundred and fifty (450) principals/vice principals randomly selected from a population of one thousand, four hundred and twenty eight (1,428) principals. The null ...

  9. Interactions between selected PAHs and the microbial community in rhizosphere of a paddy soil.

    Science.gov (United States)

    Su, Yu H; Yang, Xue Y

    2009-01-15

    This study investigated the interaction of three polycyclic aromatic hydrocarbons (PAHs), i.e., naphthalene (NAP), phenanthrene (PHN), and pyrene (PYR), with the microbial community in the rhizosphere of a paddy soil and the influence of the rice (Oryza sativa) rhizosphere on the microbial community structure. A range of initial NAP, PHN and PYR levels in soil (50-200, 18-72, and 6.6-26.6 mg kg(-1), respectively) were prepared and the soil samples were then aged for 4 months (to yield PAH concentrations at 1.02-1.42, 1.32-4.77, and 2.98-18.5 mg kg(-)(1), respectively) before the soil samples were planted with rice seedlings. The microbial phospholipid-fatty-acid (PLFA) patterns in PAH-contaminated soils were analyzed to elucidate the changes of the microbial biomass and community composition. Results indicated that at the applied concentrations the PAHs were not toxic to rice seedlings, as evidenced by no growth inhibition during the 8-week planting period. However, the microbial biomass, as revealed by PLFAs, decreased significantly with increasing PAH concentration in both rhizospheric and non-rhizospheric soils. The PAHs in soils were obviously toxic to microorganisms, and the toxicity of PHN was greater than PYR due likely to the higher PHN bioavailability. Total PLFAs in rhizospheric soils were profoundly higher than those in non-rhizospheric soils, suggesting that the inhibitive effect of PAHs on microbial activities was alleviated by the rice roots. The principal component analysis (PCA) of the PLFA signatures revealed pronounced changes in PLFA pattern in rhizospheric and non-rhizospheric soils with or without spiked PAHs. Using the PLFA patterns as a biomarker, it was found that Gram-positive bacteria were more sensitive to PAHs than Gram-negative bacteria, and the rhizosphere of rice roots stimulated the growth of aerobic bacteria.

  10. Anglo-American views of Gavrilo Princip

    Directory of Open Access Journals (Sweden)

    Markovich Slobodan G.

    2015-01-01

    Full Text Available The paper deals with Western (Anglo-American views on the Sarajevo assassination/attentat and Gavrilo Princip. Articles on the assassination and Princip in two leading quality dailies (The Times and The New York Times have particularly been analysed as well as the views of leading historians and journalists who covered the subject including: R. G. D. Laffan, R. W. Seton-Watson, Winston Churchill, Sidney Fay, Bernadotte Schmitt, Rebecca West, A. J. P. Taylor, Vladimir Dedijer, Christopher Clark and Tim Butcher. In the West, the original general condemnation of the assassination and its main culprits was challenged when Rebecca West published her famous travelogue on Yugoslavia in 1941. Another Brit, the remarkable historian A. J. P. Taylor, had a much more positive view on the Sarajevo conspirators and blamed Germany and Austria-Hungary for the outbreak of the Great War. A turning point in Anglo-American perceptions was the publication of Vladimir Dedijer’s monumental book The Road to Sarajevo (1966, which humanised the main conspirators, a process initiated by R. West. Dedijer’s book was translated from English into all major Western languages and had an immediate impact on the understanding of the Sarajevo assassination. The rise of national antagonisms in Bosnia gradually alienated Princip from Bosnian Muslims and Croats, a process that began in the 1980s and was completed during the wars of the Yugoslav succession. Although all available sources clearly show that Princip, an ethnic Serb, gradually developed a broader Serbo-Croat and Yugoslav identity, he was ethnified and seen exclusively as a Serb by Bosnian Croats and Bosniaks and Western journalists in the 1990s. In the past century imagining Princip in Serbia and the West involved a whole spectrum of views. In interwar Anglo-American perceptions he was a fanatic and lunatic. He became humanised by Rebecca West (1941, A. J. P. Taylor showed understanding for his act (1956, he was fully

  11. Principal Investigator-in-a-Box

    Science.gov (United States)

    Young, Laurence R.

    1999-01-01

    Human performance in orbit is currently limited by several factors beyond the intrinsic awkwardness of motor control in weightlessness. Cognitive functioning can be affected by such factors as cumulative sleep loss, stress and the psychological effects of long-duration small-group isolation. When an astronaut operates a scientific experiment, the performance decrement associated with such factors can lead to lost or poor quality data and even the total loss of a scientific objective, at great cost to the sponsors and to the dismay of the Principal Investigator. In long-duration flights, as anticipated on the International Space Station and on any planetary exploration, the experimental model is further complicated by long delays between training and experiment, and the large number of experiments each crew member must perform. Although no documented studies have been published on the subject, astronauts report that an unusually large number of simple errors are made in space. Whether a result of the effects of microgravity, accumulated fatigue, stress or other factors, this pattern of increased error supports the need for a computerized decision-making aid for astronauts performing experiments. Artificial intelligence and expert systems might serve as powerful tools for assisting experiments in space. Those conducting space experiments typically need assistance exactly when the planned checklist does not apply. Expert systems, which use bits of human knowledge and human methods to respond appropriately to unusual situations, have a flexibility that is highly desirable in circumstances where an invariably predictable course of action/response does not exist. Frequently the human expert on the ground is unavailable, lacking the latest information, or not consulted by the astronaut conducting the experiment. In response to these issues, we have developed "Principal Investigator-in-a-Box," or [PI], to capture the reasoning process of the real expert, the Principal

  12. Soil mechanics and analysis of soils overlying cavitose bedrock

    International Nuclear Information System (INIS)

    Drumm, E.C.

    1987-08-01

    The stability of the residual soils existing at the West Chestnut Ridge Site, Oak Ridge Reservation, Tennessee, was evaluated. The weathered bedrock below this residual soil contains numerous solution cavities, and several karst features were identified. The West Chestnut Ridge site was evaluated with respect to deformation and collapse of the residual soil into the bedrock cavities. A finite element analysis investigated the effects of bedrock cavity radius, thickness of soil overburden, and surface surcharge upon the deformational and stability characteristics of the residual soil. The results indicate that for small cavity radii, the thickness of the soil cover has little effect on the zone of yielded soil. For large cavity radii, a smaller zone of distressed soil occurs under thick soil cover than under thin soil cover. Dimensionless curves are presented to enable the prediction of the vertical extent of the zone of yielded soil for a range of site geometries. Although the thick soil deposits (100 feet or greater) typically found on the ridges result in high stresses adjacent to the cavity, the area of the distressed or yielded soil is small and unlikely to extend to the surface. In addition, the surface deformation or subsidence is expected to be minimal. Thus, the siting of waste facilities on the ridges where the overburden is maximum would tend to reduce the effects of deformation into the cavities. 29 refs., 37 figs., 7 tabs

  13. Toxicological significance of soil ingestion by wild and domestic animals

    Science.gov (United States)

    Beyer, W. Nelson; Fries, George F.; Hoffman, David J.; Rattner, Barnett A.; Burton, G. Allen; Cairns, John

    2003-01-01

    Most wild and domestic animals ingest some soil or sediment, and some species may routinely, or under special circumstances, ingest considerable amounts. Ingested soil supplies nutrients, exposes animals to parasites and pathogens, and may play a role in developing immune systems.1 Soil ingestion is also sometimes the principal route of exposure to various environmental contaminants.2-7 Ingestion of soil and earthy material is defined as geophagy and may be either intentional or unintentional, occurring as an animal eats or grooms.

  14. An Investigation of Teacher, Principal, and Superintendent Perceptions on the Ability of the National Framework for Principal Evaluations to Measure Principals' Leadership Competencies

    Science.gov (United States)

    Lamb, Lori D.

    2014-01-01

    The purpose of this qualitative study was to investigate the perceptions of effective principals' leadership competencies; determine if the perceptions of teachers, principals, and superintendents aligned with the proposed National Framework for Principal Evaluations initiative. This study examined the six domains of leadership outlined by the…

  15. Do Qualification, Experience and Age Matter for Principals Leadership Styles?

    OpenAIRE

    Muhammad Javed Sawati; Saeed Anwar; Muhammad Iqbal Majoka

    2013-01-01

    The main focus of present study was to find out the prevalent leadership styles of principals in government schools of Khyber Pakhtunkhwa and to find relationship of leadership styles with qualifications, age and experience of the principals. On the basis of analyzed data, four major leadership styles of the principals were identified as Eclectic, Democratic, Autocratic, and Free-rein. However, a small proportion of the principal had no dominant leadership style. This study shows that princip...

  16. Makran Mountain Range, Iran and Pakistan

    Science.gov (United States)

    1983-01-01

    The long folded mountain ridges and valleys of the coastal Makran Ranges of Iran and Pakistan (26.0N, 63.0E) illustrate the classical Trellis type of drainage pattern, common in this region. The Dasht River and its tributaries is the principal drainage network for this area. To the left, the continental drift of the northward bound Indian sub-continent has caused the east/west parallel ranges to bend in a great northward arc.

  17. Trust Me, Principal, or Burn Out! The Relationship between Principals' Burnout and Trust in Students and Parents

    Science.gov (United States)

    Ozer, Niyazi

    2013-01-01

    The purpose of this study was to determine the primary school principals' views on trust in students and parents and also, to explore the relationships between principals' levels of professional burnout and their trust in students and parents. To this end, Principal Trust Survey and Friedman Principal Burnout scales were administered on 119…

  18. Relaxometry in soil science

    Science.gov (United States)

    Schaumann, G. E.; Jaeger, F.; Bayer, J. V.

    2009-04-01

    NMR relaxometry is a sensitive, informative and promising method to study pore size distribution in soils as well as many kinds of soil physicochemical processes, among which are wetting, swelling or changes in the macromolecular status. Further, it is a very helpful method to study interactions between molecules in soil organic matter and it can serve to study the state of binding of water or organic chemicals to soil organic matter. The method of Relaxometry excite the nuclei of interest and their relaxation kinetics are observed. The relaxation time is the time constant of this first order relaxation process. Most applications of relaxometry concentrate on protons, addressing water molecules or H-containing organic molecules. In this context, 1H-NMR relaxometry may be used as an analysis method to determine water uptake characteristics of soils, thus gaining information about water distribution and mobility as well as pore size distribution in wet and moist samples. Additionally, it can also serve as a tool to study mobility of molecular segments in biopolymers. Principally, relaxometry is not restricted to protons. In soil science, relaxometry is also applied using deuterium, xenon and other nuclei to study pore size distribution and interactions. The relaxation time depends on numerous parameters like surface relaxivity, diffusion and interactions between nuclei as well as between nuclei and the environment. One- and two-dimensional methods address the relation between relaxation time and diffusion coefficients and can give information about the interconnectivity of pores. More specific information can be gained using field cycling techniques. Although proton NMR relaxometry is a very promising method in soil science, it has been applied scarcely up to now. It was used to assess changes in molecular rigidity of humic substances. A very recent study shows the potential of NMR relaxometry to assess the pore size distribution of soils in a fast and non

  19. A review of the impacts of degradation threats on soil properties in the UK.

    Science.gov (United States)

    Gregory, A S; Ritz, K; McGrath, S P; Quinton, J N; Goulding, K W T; Jones, R J A; Harris, J A; Bol, R; Wallace, P; Pilgrim, E S; Whitmore, A P

    2015-10-01

    National governments are becoming increasingly aware of the importance of their soil resources and are shaping strategies accordingly. Implicit in any such strategy is that degradation threats and their potential effect on important soil properties and functions are defined and understood. In this paper, we aimed to review the principal degradation threats on important soil properties in the UK, seeking quantitative data where possible. Soil erosion results in the removal of important topsoil and, with it, nutrients, C and porosity. A decline in soil organic matter principally affects soil biological and microbiological properties, but also impacts on soil physical properties because of the link with soil structure. Soil contamination affects soil chemical properties, affecting nutrient availability and degrading microbial properties, whilst soil compaction degrades the soil pore network. Soil sealing removes the link between the soil and most of the 'spheres', significantly affecting hydrological and microbial functions, and soils on re-developed brownfield sites are typically degraded in most soil properties. Having synthesized the literature on the impact on soil properties, we discuss potential subsequent impacts on the important soil functions, including food and fibre production, storage of water and C, support for biodiversity, and protection of cultural and archaeological heritage. Looking forward, we suggest a twin approach of field-based monitoring supported by controlled laboratory experimentation to improve our mechanistic understanding of soils. This would enable us to better predict future impacts of degradation processes, including climate change, on soil properties and functions so that we may manage soil resources sustainably.

  20. Making Sense of Social Justice Leadership: A Case Study of a Principal's Experiences to Create a More Inclusive School

    Science.gov (United States)

    DeMatthews, David

    2015-01-01

    Social justice leadership in high-poverty urban schools is complex. Principals experience a range of feelings and emotions while practicing social justice leadership with implications on their leadership. This article presents a qualitative case study of an elementary school principal in an urban setting and how she led to create a more inclusive…

  1. Soil pollution and soil protection

    OpenAIRE

    Haan, de, F.A.M.; Visser-Reijneveld, M.I.

    1996-01-01

    This book was compiled from lecture handouts prepared for the international postgraduate course on soil quality, entitled 'Soil Pollution and Soil Protection' given jointly by the universities of Wageningen (The Netherlands), Gent and Leuven (Belgium), under the auspices of the international Training Centre (PHLO) of Wageningen Agricultural University.Of the three environmental compartments air, water and soil, it is soil that varies most in composition under natural conditions. The effects o...

  2. Radar fall detection using principal component analysis

    Science.gov (United States)

    Jokanovic, Branka; Amin, Moeness; Ahmad, Fauzia; Boashash, Boualem

    2016-05-01

    Falls are a major cause of fatal and nonfatal injuries in people aged 65 years and older. Radar has the potential to become one of the leading technologies for fall detection, thereby enabling the elderly to live independently. Existing techniques for fall detection using radar are based on manual feature extraction and require significant parameter tuning in order to provide successful detections. In this paper, we employ principal component analysis for fall detection, wherein eigen images of observed motions are employed for classification. Using real data, we demonstrate that the PCA based technique provides performance improvement over the conventional feature extraction methods.

  3. Transuranic Behavior in Soils and Plants

    International Nuclear Information System (INIS)

    Wildung, R.E.; Garland, T.R.; Cataldo, D.A.; Rogers, J.E.; McFadden, K.M.; McNair, V.M.; Schreckhise, R.G.

    1980-01-01

    The principal objectives of these investigations are to determine (1) the potential for alteration of transuranic solubility through formation of transuranic complexes in soil and the role of the soil microflora in this process, (2) the extent of uptake nd translocation by plants and the sites of plant deposition of transuranics or their complexes, (3) the bond types and chemical forms of transuranics or their metabolites in microbes, plant tissues and soils, (4) the influence of soil properties, environmental conditions and cropping on these processes, and (5) the retention of airborne pollutants by plant foliage and their subsequent absorption by leaves and transport to seeds and roots

  4. Soil! Get the Scoop - The Soil Science Society of America's International Year of Soils Campaign

    Science.gov (United States)

    Lindbo, David L.; Hopmans, Jan; Olson, Carolyn; Fisk, Susan; Chapman, Susan; van Es, Harold

    2015-04-01

    Soils are a finite natural resource and are nonrenewable on a human time scale. Soils are the foundation for food, animal feed, fuel and natural fiber production, the supply of clean water, nutrient cycling and a range of ecosystem functions. The area of fertile soils covering the world's surface is limited and increasingly subject to degradation, poor management and loss to urbanization. Increased awareness of the life-supporting functions of soil is called for if this trend is to be reversed and so enable the levels of food production necessary to meet the demands of population levels predicted for 2050. The Soil Science Society of America is coordinating with the Global Soil Partnership and other organizations around the world to celebrate the 2015 International Year of Soils and raise awareness and promote the sustainability of our limited soil resources. We all have a valuable role in communicating vital information on soils, a life sustaining natural resource. Therefore, we will provide resources to learn about soils and help us tell the story of soils. We will promote IYS on social media by sharing our posts from Facebook and Twitter. Additionally SSSA developed 12 monthly themes that reflect the diverse value of soils to our natural environment and society. Each month has information on the theme, a lesson plan, and other outreach activities. All information is available on a dedicated website www.soil.org/IYS. The site will be updated constantly throughout the year.

  5. Relationships among plutonium contents of soil, vegetation and animals collected on and adjacent to an integrated nuclear complex in the humid southeastern United States of America

    International Nuclear Information System (INIS)

    McLendon, H.R.

    1976-01-01

    Twenty-three representative sampling locations on and adjacent to the Savannah River Plant (SRP) site were selected to obtain information on plutonium movement in the food chain under southeastern US environmental conditions. Soil, a resuspendible fraction of the soil, honeysuckle (Lonicera japonica), and camphor weed (Heterotheca subaxillaris) were collected at each location. Grasshoppers and cotton rats (Sigmodon hispidus) were collected at some locations. The plutonium concentrations in soil at the selected locations ranged from 1.5 to 171fCi/g and alpha percentages of 238 Pu ranged from 2 to 66. The concentration of plutonium in the vegetation and on the leaves ranged from 0.17 to 76.1fCi/g and the alpha percentages of 238 Pu from 3 to 61. The concentration of plutonium in cotton rats and grasshoppers ranged from 0.07 to 3.58fCi/g and the alpha percentages of 238 Pu ranged from 22 to 80. The average ratio of plutonium concentration of vegetation to that of the surrounding soil was 10 -1 ; the corresponding ratio for cotton rats and soil was 10 -2 . These ratios appear to be independent of the plutonium concentration in the soil. Deposition on the surfaces of leaves and stems was the principal mechanism of plutonium contamination of vegetation. Comparisons among the plutonium values of the vegetation, soil and resuspendible fraction suggest the use of a proposed resuspendible measurement technique as a monitoring method to indicate subtle changes in the plutonium concentration of the soil surface that are not detectable by routine soil sampling. Although the 238 Pu data in the various ecosystem components were not conclusive, they do support evidence presented in other studies that there is an apparent increase in the biological availability of 238 Pu relative to that of sup(239,240)Pu in the environment. The plutonium concentrations of all ecosystem components decreased as the distance from the reprocessing plants increased. (author)

  6. DEGRADATION AND MIGRATION OF VINCLOZOLIN IN SAND AND SOIL

    Science.gov (United States)

    The migration of the dicarboximide fungicide vinclozolin and its principal degradation products through porous media was experimentally determined by simulating pesticide applications to a 23-30 mesh Ottawa sand and a North Carolina Piedmont, aquic hapludult soil in laboratory ...

  7. Soil CO2 flux from three ecosystems in tropical peatland of Sarawak, Malaysia

    International Nuclear Information System (INIS)

    Melling, Lulie; Hatano, Ryusuke

    2005-01-01

    Soil CO 2 flux was measured monthly over a year from tropical peatland of Sarawak, Malaysia using a closed-chamber technique. The soil CO 2 flux ranged from 100 to 533 mg C/m 2 /h for the forest ecosystem, 63 to 245 mg C/m 2 /h for the sago and 46 to 335 mg C/m 2 /h for the oil palm. Based on principal component analysis (PCA), the environmental variables over all sites could be classified into three components, namely, climate, soil moisture and soil bulk density, which accounted for 86% of the seasonal variability. A regression tree approach showed that CO 2 flux in each ecosystem was related to different underlying environmental factors. They were relative humidity for forest, soil temperature at 5 cm for sago and water-filled pore space for oil palm. On an annual basis, the soil CO 2 flux was highest in the forest ecosystem with an estimated production of 2.1 kg C/m 2 /yr followed by oil palm at 1.5 kg C/m 2 /yr and sago at 1.1 kg C/m 2 /yr. The different dominant controlling factors in CO 2 flux among the studied ecosystems suggested that land use affected the exchange of CO 2 between tropical peatland and the atmosphere

  8. Principal forensic physicians as educational supervisors.

    Science.gov (United States)

    Stark, Margaret M

    2009-10-01

    This research project was performed to assist the Faculty of Forensic and Legal Medicine (FFLM) with the development of a training programme for Principal Forensic Physicians (PFPs) (Since this research was performed the Metropolitan Police Service have dispensed with the services of the Principal Forensic Physicians so currently (as of January 2009) there is no supervision of newly appointed FMEs or the development training of doctors working in London nor any audit or appraisal reviews.) to fulfil their role as educational supervisors. PFPs working in London were surveyed by questionnaire to identify the extent of their knowledge with regard to their role in the development training of all forensic physicians (FPs) in their group, the induction of assistant FPs and their perceptions of their own training needs with regard to their educational role. A focus group was held at the FFLM annual conference to discuss areas of interest that arose from the preliminary results of the questionnaire. There is a clear need for the FFLM to set up a training programme for educational supervisors in clinical forensic medicine, especially with regard to appraisal. 2009 Elsevier Ltd and Faculty of Forensic and Legal Medicine.

  9. A Technical Design Approach to Soil Moisture Content Measurement

    African Journals Online (AJOL)

    Soil moisture is an important type of data in many fields; ranging from agriculture to environmental monitoring. Three soil samples were collected at definite proportions to represent the three basic soil types (sandy, loamy and clay soils). The moisture contents of these soil samples were analyzed using the thermogravimetric ...

  10. Three representative UK moorland soils show differences in decadal release of dissolved organic carbon in response to environmental change

    Directory of Open Access Journals (Sweden)

    M. I. Stutter

    2011-12-01

    Full Text Available Moorland carbon reserves in organo-mineral soils may be crucial to predicting landscape-scale variability in soil carbon losses, an important component of which is dissolved organic carbon (DOC. Surface water DOC trends are subject to a range of scaling, transport and biotic processes that disconnect them from signals in the catchment's soils. Long-term soil datasets are vital to identify changes in DOC release at source and soil C depletion. Here we show, that moorland soil solution DOC concentrations at three key UK Environmental Change Network sites increased between 1993–2007 in both surface- and sub- soil of a freely-draining Podzol (48 % and 215 % increases in O and Bs horizons, respectively, declined in a gleyed Podzol and showed no change in a Peat. Our principal findings were that: (1 considerable heterogeneity in DOC response appears to exist between different soils that is not apparent from the more consistent observed trends for streamwaters, and (2 freely-draining organo-mineral Podzol showed increasing DOC concentrations, countering the current scientific focus on soil C destabilization in peats. We discuss how the key solubility controls on DOC associated with coupled physico-chemical factors of ionic strength, acid deposition recovery, soil hydrology and temperature cannot readily be separated. Yet, despite evidence that all sites are recovering from acidification the soil-specific responses to environmental change have caused divergence in soil DOC concentration trends. The study shows that the properties of soils govern their specific response to an approximately common set of broad environmental drivers. Key soil properties are indicated to be drainage, sulphate and DOC sorption capacity. Soil properties need representation in process-models to understand and predict the role of soils in catchment to global C budgets. Catchment hydrological (i.e. transport controls may, at present, be governing the more ubiquitous rises in

  11. Principal and secondary luminescence lifetime components in annealed natural quartz

    International Nuclear Information System (INIS)

    Chithambo, M.L.; Ogundare, F.O.; Feathers, J.

    2008-01-01

    Time-resolved luminescence spectra from quartz can be separated into components with distinct principal and secondary lifetimes depending on certain combinations of annealing and measurement temperature. The influence of annealing on properties of the lifetimes related to irradiation dose and temperature of measurement has been investigated in sedimentary quartz annealed at various temperatures up to 900 deg. C. Time-resolved luminescence for use in the analysis was pulse stimulated from samples at 470 nm between 20 and 200 deg. C. Luminescence lifetimes decrease with measurement temperature due to increasing thermal effect on the associated luminescence with an activation energy of thermal quenching equal to 0.68±0.01eV for the secondary lifetime but only qualitatively so for the principal lifetime component. Concerning the influence of annealing temperature, luminescence lifetimes measured at 20 deg. C are constant at about 33μs for annealing temperatures up to 600 0 C but decrease to about 29μs when the annealing temperature is increased to 900 deg. C. In addition, it was found that lifetime components in samples annealed at 800 deg. C are independent of radiation dose in the range 85-1340 Gy investigated. The dependence of lifetimes on both the annealing temperature and magnitude of radiation dose is described as being due to the increasing importance of a particular recombination centre in the luminescence emission process as a result of dynamic hole transfer between non-radiative and radiative luminescence centres

  12. Thermal remediation alters soil properties - a review.

    Science.gov (United States)

    O'Brien, Peter L; DeSutter, Thomas M; Casey, Francis X M; Khan, Eakalak; Wick, Abbey F

    2018-01-15

    Contaminated soils pose a risk to human and ecological health, and thermal remediation is an efficient and reliable way to reduce soil contaminant concentration in a range of situations. A primary benefit of thermal treatment is the speed at which remediation can occur, allowing the return of treated soils to a desired land use as quickly as possible. However, this treatment also alters many soil properties that affect the capacity of the soil to function. While extensive research addresses contaminant reduction, the range and magnitude of effects to soil properties have not been explored. Understanding the effects of thermal remediation on soil properties is vital to successful reclamation, as drastic effects may preclude certain post-treatment land uses. This review highlights thermal remediation studies that have quantified alterations to soil properties, and it supplements that information with laboratory heating studies to further elucidate the effects of thermal treatment of soil. Notably, both heating temperature and heating time affect i) soil organic matter; ii) soil texture and mineralogy; iii) soil pH; iv) plant available nutrients and heavy metals; v) soil biological communities; and iv) the ability of the soil to sustain vegetation. Broadly, increasing either temperature or time results in greater contaminant reduction efficiency, but it also causes more severe impacts to soil characteristics. Thus, project managers must balance the need for contaminant reduction with the deterioration of soil function for each specific remediation project. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Integrated GIS and multivariate statistical analysis for regional scale assessment of heavy metal soil contamination: A critical review

    International Nuclear Information System (INIS)

    Hou, Deyi; O'Connor, David; Nathanail, Paul; Tian, Li; Ma, Yan

    2017-01-01

    Heavy metal soil contamination is associated with potential toxicity to humans or ecotoxicity. Scholars have increasingly used a combination of geographical information science (GIS) with geostatistical and multivariate statistical analysis techniques to examine the spatial distribution of heavy metals in soils at a regional scale. A review of such studies showed that most soil sampling programs were based on grid patterns and composite sampling methodologies. Many programs intended to characterize various soil types and land use types. The most often used sampling depth intervals were 0–0.10 m, or 0–0.20 m, below surface; and the sampling densities used ranged from 0.0004 to 6.1 samples per km 2 , with a median of 0.4 samples per km 2 . The most widely used spatial interpolators were inverse distance weighted interpolation and ordinary kriging; and the most often used multivariate statistical analysis techniques were principal component analysis and cluster analysis. The review also identified several determining and correlating factors in heavy metal distribution in soils, including soil type, soil pH, soil organic matter, land use type, Fe, Al, and heavy metal concentrations. The major natural and anthropogenic sources of heavy metals were found to derive from lithogenic origin, roadway and transportation, atmospheric deposition, wastewater and runoff from industrial and mining facilities, fertilizer application, livestock manure, and sewage sludge. This review argues that the full potential of integrated GIS and multivariate statistical analysis for assessing heavy metal distribution in soils on a regional scale has not yet been fully realized. It is proposed that future research be conducted to map multivariate results in GIS to pinpoint specific anthropogenic sources, to analyze temporal trends in addition to spatial patterns, to optimize modeling parameters, and to expand the use of different multivariate analysis tools beyond principal component

  14. Solarization soil

    International Nuclear Information System (INIS)

    Abou Ghraibe, W.

    1995-01-01

    Solar energy could be used in pest control, in soil sterilization technology. The technique consists of covering humid soils by plastic films steadily fixed to the soil. Timing must be in summer during 4-8 weeks, where soil temperature increases to degrees high enough to control pests or to produce biological and chemical changes. The technique could be applied on many pests soil, mainly fungi, bacteria, nematods, weeds and pest insects. The technique could be used in greenhouses as well as in plastic film covers or in orchards where plastic films present double benefits: soil sterilization and production of black mulch. Mechanism of soil solarization is explained. Results show that soil solarization can be used in pest control after fruit crops cultivation and could be a method for an integrated pest control. 9 refs

  15. How does soil management affect carbon losses from soils?

    Science.gov (United States)

    Klik, A.; Trümper, G.

    2009-04-01

    Agricultural soils are a major source as well as a sink of organic carbon (OC). Amount and distribution of OC within the soil and within the landscape are driven by land management but also by erosion and deposition processes. At the other hand the type of soil management influences mineralization and atmospheric carbon dioxide losses by soil respiration. In a long-term field experiment the impacts of soil tillage systems on soil erosion processes were investigated. Following treatments were compared: 1) conventional tillage (CT), 2) conservation tillage with cover crop during the winter period (CS), and 3) no-till with cover crop during winter period (NT). The studies were carried out at three sites in the Eastern part of Austria with annual precipitation amounts from 650 to 900 mm. The soil texture ranged from silt loam to loam. Since 2007 soil CO2 emissions are measured with a portable soil respiration system in intervals of about one week, but also in relation to management events. Concurrent soil temperature and soil water content are measured and soil samples are taken for chemical and microbiological analyses. An overall 14-yr. average soil loss between 1.0 t.ha-1.yr-1 for NT and 6.1 t.ha-1.yr-1 for CT resulted in on-site OC losses from 18 to 79 kg ha-1.yr-1. The measurements of the carbon dioxide emissions from the different treatments indicate a high spatial variation even within one plot. Referred to CT plots calculated carbon losses amounted to 65-94% for NT plots while for the different RT plots they ranged between 84 and 128%. Nevertheless site specific considerations have to be taken into account. Preliminary results show that the adaptation of reduced or no-till management strategies has enormous potential in reducing organic carbon losses from agricultural used soils.

  16. Integrating Data Transformation in Principal Components Analysis

    KAUST Repository

    Maadooliat, Mehdi

    2015-01-02

    Principal component analysis (PCA) is a popular dimension reduction method to reduce the complexity and obtain the informative aspects of high-dimensional datasets. When the data distribution is skewed, data transformation is commonly used prior to applying PCA. Such transformation is usually obtained from previous studies, prior knowledge, or trial-and-error. In this work, we develop a model-based method that integrates data transformation in PCA and finds an appropriate data transformation using the maximum profile likelihood. Extensions of the method to handle functional data and missing values are also developed. Several numerical algorithms are provided for efficient computation. The proposed method is illustrated using simulated and real-world data examples.

  17. Reinvention and the Principal-Agent Model

    Directory of Open Access Journals (Sweden)

    J. Ramón Gil García

    2003-01-01

    Full Text Available Existe una interesante polémica en el sector público, derivada de las tensiones existentes entre desempeño y flexibilidad administrativa por un lado, y rendición de cuentas y control, por el otro. El propósito de este artículo es discutir la utilidad del modelo agente principal para un mejor entendimiento de las tensiones entre desempeño y rendición de cuentas, así como analizar las similitudes y contradicciones de esta perspectiva teórica en comparación con el movimiento de “reinvención del gobierno” de la década de los noventa en Estados Unidos.

  18. Nonlinear principal component analysis and its applications

    CERN Document Server

    Mori, Yuichi; Makino, Naomichi

    2016-01-01

    This book expounds the principle and related applications of nonlinear principal component analysis (PCA), which is useful method to analyze mixed measurement levels data. In the part dealing with the principle, after a brief introduction of ordinary PCA, a PCA for categorical data (nominal and ordinal) is introduced as nonlinear PCA, in which an optimal scaling technique is used to quantify the categorical variables. The alternating least squares (ALS) is the main algorithm in the method. Multiple correspondence analysis (MCA), a special case of nonlinear PCA, is also introduced. All formulations in these methods are integrated in the same manner as matrix operations. Because any measurement levels data can be treated consistently as numerical data and ALS is a very powerful tool for estimations, the methods can be utilized in a variety of fields such as biometrics, econometrics, psychometrics, and sociology. In the applications part of the book, four applications are introduced: variable selection for mixed...

  19. Nuclear reaction analysis of hydrogen in materials: Principals and applications

    International Nuclear Information System (INIS)

    Lanford, W.A.

    1991-01-01

    Analysis for hydrogen in materials is difficult by most traditional analytic methods. Because hydrogen has no Auger transitions, no X-ray transitions, does not neutron activate, and does not backscatter ions, it is invisible in analytical methods based on these effects. In addition, since hydrogen is a universal contaminant in vacuum systems, techniques based on mass spectrometry are difficult unless extreme measures are taken to reduce hydrogen backgrounds. Because of this situation, methods have been developed for analyzing for hydrogen in solid materials based on nuclear reactions between bombarding ions and hydrogen atoms (protons) in the samples. The nuclear reaction methods are now practiced at laboratories around the world. The basic principals of nuclear reaction analysis will be briefly presented. This method will be illustrated by applications to problems ranging from basic physics, to geology, to materials science, and to art history and archeology

  20. Teacher and Principal Perceptions of How Principal Transformational and Instructional Leadership Behaviors Relate to Student Achievement

    Science.gov (United States)

    Steele, Gayle

    2012-01-01

    Because of public concern over the effectiveness of our schools, a new evaluation system was put in place to hold principals and teachers directly accountable for student academic achievement. Part of this evaluation included student performance on state assessments. The purpose of this qualitative study sought to examine how the transformation…

  1. The Networked Principal: Examining Principals' Social Relationships and Transformational Leadership in School and District Networks

    Science.gov (United States)

    Moolenaar, Nienke M.; Sleegers, Peter J. C.

    2015-01-01

    Purpose: While in everyday practice, school leaders are often involved in social relationships with a variety of stakeholders both within and outside their own schools, studies on school leaders' networks often focus either on networks within or outside schools. The purpose of this paper is to investigate the extent to which principals occupy…

  2. Soils - Volusia County Soils (Polygons)

    Data.gov (United States)

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

  3. Soil microbiology and soil health assessment

    Science.gov (United States)

    Soil scientists have long recognized the importance of soil biology in ecological health. In particular, soil microbes are crucial for many soil functions including decomposition, nutrient cycling, synthesis of plant growth regulators, and degradation of synthetic chemicals. Currently, soil biologis...

  4. Soil metagenomics and tropical soil productivity

    OpenAIRE

    Garrett, Karen A.

    2009-01-01

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

  5. Principals' Perceived Supervisory Behaviors Regarding Marginal Teachers in Two States

    Science.gov (United States)

    Range, Bret; Hewitt, Paul; Young, Suzie

    2014-01-01

    This descriptive study used an online survey to determine how principals in two states viewed the supervision of marginal teachers. Principals ranked their own evaluation of the teacher as the most important factor when identifying marginal teachers and relied on informal methods to diagnose marginal teaching. Female principals rated a majority of…

  6. District Leadership for Effective Principal Evaluation and Support

    Science.gov (United States)

    Kimball, Steven M.; Arrigoni, Jessica; Clifford, Matthew; Yoder, Maureen; Milanowski, Anthony

    2015-01-01

    Research demonstrating principals' impact on student learning outcomes has fueled the shift from principals as facilities managers to an emphasis on instructional leadership (Hallinger & Heck, 1996; Leithwood, Louis, Anderson, & Wahlstrom, 2004; Marzano, Waters, & McNulty, 2005). Principals are under increasing pressure to carry out…

  7. Principal Leadership for Technology-enhanced Learning in Science

    Science.gov (United States)

    Gerard, Libby F.; Bowyer, Jane B.; Linn, Marcia C.

    2008-02-01

    Reforms such as technology-enhanced instruction require principal leadership. Yet, many principals report that they need help to guide implementation of science and technology reforms. We identify strategies for helping principals provide this leadership. A two-phase design is employed. In the first phase we elicit principals' varied ideas about the Technology-enhanced Learning in Science (TELS) curriculum materials being implemented by teachers in their schools, and in the second phase we engage principals in a leadership workshop designed based on the ideas they generated. Analysis uses an emergent coding scheme to categorize principals' ideas, and a knowledge integration framework to capture the development of these ideas. The analysis suggests that principals frame their thinking about the implementation of TELS in terms of: principal leadership, curriculum, educational policy, teacher learning, student outcomes and financial resources. They seek to improve their own knowledge to support this reform. The principals organize their ideas around individual school goals and current political issues. Principals prefer professional development activities that engage them in reviewing curricula and student work with other principals. Based on the analysis, this study offers guidelines for creating learning opportunities that enhance principals' leadership abilities in technology and science reform.

  8. Contemporary Challenges and Changes: Principals' Leadership Practices in Malaysia

    Science.gov (United States)

    Jones, Michelle; Adams, Donnie; Joo, Mabel Tan Hwee; Muniandy, Vasu; Perera, Corinne Jaqueline; Harris, Alma

    2015-01-01

    This article outlines the findings from a contemporary study of principals' leadership practices in Malaysia as part of the 7 System Leadership Study. Recent policy developments within Malaysia have increased principals' accountability and have underlined the importance of the role of the principals in transforming school performance and student…

  9. Common Core Implementation Decisions Made by Principals in Elementary Schools

    Science.gov (United States)

    Norman, Alexis Cienfuegos

    2016-01-01

    The purpose of this study was to understand the decisions elementary principals have made during the Common Core State Standards reform. Specifically, (a) what decisions principals have made to support Common Core implementation, (b) what strategies elementary principals have employed to communicate with stakeholders about Common Core State…

  10. Job Satisfaction of Elementary Principals in Large Urban Communities

    Science.gov (United States)

    Mitchell, Cathryn M.

    2010-01-01

    The purpose of this study was to determine job satisfaction levels of elementary principals in "major urban" districts in Texas and to identify strategies these principals used to cope with the demands of the position. Additionally, the project sought to find structures and supports needed to attract and retain principals in the…

  11. Taking a Distributed Perspective to the School Principal's Workday

    Science.gov (United States)

    Spillane, James P.; Camburn, Eric M.; Pareja, Amber Stitziel

    2007-01-01

    Focusing on the school principal's day-to-day work, we examine who leads curriculum and instruction- and administration-related activities when the school principal is not leading but participating in the activity. We also explore the prevalence of coperformance of management and leadership activities in the school principal's workday. Looking…

  12. Aerobic Physical Activity and the Leadership of Principals

    Science.gov (United States)

    Kiser, Kari

    2016-01-01

    The purpose of this study was to explore if there was a connection between regular aerobic physical activity and the stress and energy levels of principals as they reported it. To begin the research, the current aerobic physical activity level of principals was discovered. Additionally, the energy and stress levels of the principals who do engage…

  13. Principal Preparation in Special Education: Building an Inclusive Culture

    Science.gov (United States)

    Hofreiter, Deborah

    2017-01-01

    The importance of principal preparation in special education has increased since the Education for All Handicapped Children Act was passed in 1975. There are significant financial reasons for preparing principals in the area of special education. Recent research also shows that all children learn better in an inclusive environment. Principals who…

  14. How the Principalship Has Changed: Lessons from Principals' Life Stories.

    Science.gov (United States)

    Brubaker, Dale L.

    1995-01-01

    The life stories of (North Carolina) principals in a graduate education class reveal vast changes over the past 20 years. "Good ol' boy" superintendents and principals have been replaced by self-interested political "sharks" concerned more with image than substance. Fortunately, principals with resiliency, caring values, and…

  15. Principal Turnover: Upheaval and Uncertainty in Charter Schools?

    Science.gov (United States)

    Ni, Yongmei; Sun, Min; Rorrer, Andrea

    2015-01-01

    Purpose: Informed by literature on labor market and school choice, this study aims to examine the dynamics of principal career movements in charter schools by comparing principal turnover rates and patterns between charter schools and traditional public schools. Research Methods/Approach: This study uses longitudinal data on Utah principals and…

  16. A Review of the Literature on Principal Turnover

    Science.gov (United States)

    Snodgrass Rangel, Virginia

    2018-01-01

    Among the many challenges facing public schools are high levels of principal turnover. Given the important role that principals play and are expected to play in the improvement process, concerns about principal turnover have resulted in a growing body of research on its causes and consequences. The purpose of this review is to take stock of what…

  17. Principal Holistic Judgments and High-Stakes Evaluations of Teachers

    Science.gov (United States)

    Briggs, Derek C.; Dadey, Nathan

    2017-01-01

    Results from a sample of 1,013 Georgia principals who rated 12,617 teachers are used to compare holistic and analytic principal judgments with indicators of student growth central to the state's teacher evaluation system. Holistic principal judgments were compared to mean student growth percentiles (MGPs) and analytic judgments from a formal…

  18. Urban School Principals and Their Role as Multicultural Leaders

    Science.gov (United States)

    Gardiner, Mary E.; Enomoto, Ernestine K.

    2006-01-01

    This study focuses on the role of urban school principals as multicultural leaders. Using cross-case analysis, the authors describe what 6 practicing principals do in regard to multicultural leadership. The findings suggest that although multicultural preparation was lacking for these principals, some did engage in work that promoted diversity in…

  19. School Restructuring and the Dilemmas of Principals' Work.

    Science.gov (United States)

    Wildy, Helen; Louden, William

    2000-01-01

    The complexity of principals' work may be characterized according to three dilemmas: accountability, autonomy, and efficiency. Narrative vignettes of 74 Australian principals revealed that principals were fair and inclusive. When faced with restructuring dilemmas, however, they favored strong over shared leadership, efficiency over collaboration,…

  20. Importance of an Effective Principal-Counselor Relationship

    Science.gov (United States)

    Edwards, LaWanda; Grace, Ronald; King, Gwendolyn

    2014-01-01

    An effective relationship between the principal and school counselor is essential when improving student achievement. To have an effective relationship, there must be communication, trust and respect, leadership, and collaborative planning between the principal and school counselor (College Board, 2011). Principals and school counselors are both…

  1. Honouring Roles: The Story of a Principal and a Student

    Science.gov (United States)

    Cranston, Jerome

    2012-01-01

    The importance of the teacher-student relationship in educational practice is well established, as is the idea of principal leadership in relationship to staff. Even though principal leadership is regarded as a factor in student success, the principal's effect is usually assumed to take place via the teaching staff. There is an absence of research…

  2. Leadership Behaviors and Its Relation with Principals' Management Experience

    Science.gov (United States)

    Mehdinezhad, Vali; Sardarzahi, Zaid

    2016-01-01

    This paper aims at studying the leadership behaviors reported by principals and observed by teachers and its relationship with management experience of principals. A quantitative method was used in this study. The target population included all principals and teachers of guidance schools and high schools in the Dashtiari District, Iran. A sample…

  3. Use of Sparse Principal Component Analysis (SPCA) for Fault Detection

    DEFF Research Database (Denmark)

    Gajjar, Shriram; Kulahci, Murat; Palazoglu, Ahmet

    2016-01-01

    Principal component analysis (PCA) has been widely used for data dimension reduction and process fault detection. However, interpreting the principal components and the outcomes of PCA-based monitoring techniques is a challenging task since each principal component is a linear combination of the ...

  4. Soil pollution and soil protection

    NARCIS (Netherlands)

    Haan, de F.A.M.; Visser-Reijneveld, M.I.

    1996-01-01

    This book was compiled from lecture handouts prepared for the international postgraduate course on soil quality, entitled 'Soil Pollution and Soil Protection' given jointly by the universities of Wageningen (The Netherlands), Gent and Leuven (Belgium), under the auspices of the international

  5. Attenuation coefficients of soils

    International Nuclear Information System (INIS)

    Martini, E.; Naziry, M.J.

    1989-01-01

    As a prerequisite to the interpretation of gamma-spectrometric in situ measurements of activity concentrations of soil radionuclides the attenuation of 60 to 1332 keV gamma radiation by soil samples varying in water content and density has been investigated. A useful empirical equation could be set up to describe the dependence of the mass attenuation coefficient upon photon energy for soil with a mean water content of 10%, with the results comparing well with data in the literature. The mean density of soil in the GDR was estimated at 1.6 g/cm 3 . This value was used to derive the linear attenuation coefficients, their range of variation being 10%. 7 figs., 5 tabs. (author)

  6. Arsenic and Heavy Metal Contamination in Soils under Different Land Use in an Estuary in Northern Vietnam.

    Science.gov (United States)

    Nguyen Van, Thinh; Ozaki, Akinori; Nguyen Tho, Hoang; Nguyen Duc, Anh; Tran Thi, Yen; Kurosawa, Kiyoshi

    2016-11-05

    Heavy metal contamination of soil and sediment in estuaries warrants study because a healthy estuarine environment, including healthy soil, is important in order to achieve ecological balance and good aquaculture production. The Ba Lat estuary of the Red River is the largest estuary in northern Vietnam and is employed in various land uses. However, the heavy metal contamination of its soil has not yet been reported. The following research was conducted to clarify contamination levels, supply sources, and the effect of land use on heavy metal concentrations in the estuary. Soil samples were collected from the top soil layer of the estuary, and their arsenic (As), chromium (Cr), cadmium (Cd), copper (Cu), lead (Pb), and zinc (Zn) concentrations were analyzed, as were other soil properties. Most soils in the estuary were loam, silt loam, or sandy loam. The pH was neutral, and the cation exchange capacity ranged from 3.8 to 20 cmol·kg -1 . Manganese and iron concentrations averaged 811 µg·g -1 and 1.79%, respectively. The magnitude of the soil heavy metal concentrations decreased in the order of Zn > Pb > Cr > Cu > As > Cd. The concentrations were higher in the riverbed and mangrove forest than in other land-use areas. Except for As, the mean heavy metal concentrations were lower than the permissible levels for agricultural soils in Vietnam. The principal component analyses suggested that soil As, Pb, Zn, Cd, and Cu were of anthropogenic origin, whereas Cr was of non-anthropogenic origin. The spatial distribution of concentration with land use indicated that mangrove forests play an important role in preventing the spread of heavy metals to other land uses and in maintaining the estuarine environment.

  7. Arsenic and Heavy Metal Contamination in Soils under Different Land Use in an Estuary in Northern Vietnam

    Directory of Open Access Journals (Sweden)

    Thinh Nguyen Van

    2016-11-01

    Full Text Available Heavy metal contamination of soil and sediment in estuaries warrants study because a healthy estuarine environment, including healthy soil, is important in order to achieve ecological balance and good aquaculture production. The Ba Lat estuary of the Red River is the largest estuary in northern Vietnam and is employed in various land uses. However, the heavy metal contamination of its soil has not yet been reported. The following research was conducted to clarify contamination levels, supply sources, and the effect of land use on heavy metal concentrations in the estuary. Soil samples were collected from the top soil layer of the estuary, and their arsenic (As, chromium (Cr, cadmium (Cd, copper (Cu, lead (Pb, and zinc (Zn concentrations were analyzed, as were other soil properties. Most soils in the estuary were loam, silt loam, or sandy loam. The pH was neutral, and the cation exchange capacity ranged from 3.8 to 20 cmol·kg−1. Manganese and iron concentrations averaged 811 µg·g−1 and 1.79%, respectively. The magnitude of the soil heavy metal concentrations decreased in the order of Zn > Pb > Cr > Cu > As > Cd. The concentrations were higher in the riverbed and mangrove forest than in other land-use areas. Except for As, the mean heavy metal concentrations were lower than the permissible levels for agricultural soils in Vietnam. The principal component analyses suggested that soil As, Pb, Zn, Cd, and Cu were of anthropogenic origin, whereas Cr was of non-anthropogenic origin. The spatial distribution of concentration with land use indicated that mangrove forests play an important role in preventing the spread of heavy metals to other land uses and in maintaining the estuarine environment.

  8. Estimates of soil ingestion by wildlife

    Science.gov (United States)

    Beyer, W.N.; Connor, E.E.; Gerould, S.

    1994-01-01

    at intermediate rates. Ingested soil may be the principal means of exposure to some environmental contaminants or the principal source of certain minerals. Soil-ingestion estimates may be required for risk assessments of wildlife inhabiting contaminated sites and for computing budgets of those nutrients associated mainly with soil.

  9. [Influence of Different Straws Returning with Landfill on Soil Microbial Community Structure Under Dry and Water Farming].

    Science.gov (United States)

    Lan, Mu-ling; Gao, Ming

    2015-11-01

    Based on rice, wheat, corn straw and rape, broad bean green stalk as the research object, using phospholipid fatty acid (PLFA) method, combining principal component analysis method to study the soil microbial quantity, distribution of flora, community structure characteristics under dry and water farming as two different cultivated land use types. The PLFA analysis results showed that: under dry farming, total PLFA quantity ranged 8.35-25.15 nmol x g(-1), showed rape > broad bean > corn > rice > wheat, rape and broad bean significantly increased total PLFA quantity by 1.18 and 1.08 times compared to the treatment without straw; PLFA quantity of bacterial flora in treatments with straws was higher than that without straw, and fungal biomass was significantly increased, so was the species richness of microbial community. Under water faming, the treatments of different straws returning with landfill have improved the PLFA quantity of total soil microbial and flora comparing with the treatment without straw, fungi significantly increased, and species richness of microbial communities value also increased significantly. Total PLFA quantity ranged 4.04-22.19 nmol x g(-1), showed rice > corn > wheat > broad bean > rape, which in rape and broad bean treatments were lower than the treatment without straw; fungal PLFA amount in 5 kinds of straw except broad bean treatment was significantly higher than that of the treatment without straw, bacteria and total PLFA quantity in broad bean processing were significantly lower than those of other treatments, actinomycetes, G+, G- had no significant difference between all treatments; rice, wheat, corn, rape could significantly increase the soil microbial species richness index and dominance index under water faming. The results of principal component analysis showed that broad bean green stalk had the greatest impact on the microbial community structure in the dry soil, rape green stalk and wheat straw had the biggest influence on

  10. Subjective performance evaluations and reciprocity in principal-agent relations

    DEFF Research Database (Denmark)

    Sebald, Alexander Christopher; Walzl, Markus

    2014-01-01

    . In contrast to existing models of reciprocity, we find that agents tend to sanction whenever the feedback of principals is below their subjective self-evaluations even if agents' pay-offs are independent of it. In turn, principals provide more positive feedback (relative to their actual performance assessment......We conduct a laboratory experiment with agents working on, and principals benefiting from, a real effort task in which the agents' performance can only be evaluated subjectively. Principals give subjective performance feedback to agents, and agents have an opportunity to sanction principals...... of the agent) if this does not affect their pay-off....

  11. Measuring Principal Performance: How Rigorous Are Commonly Used Principal Performance Assessment Instruments? A Quality School Leadership Issue Brief

    Science.gov (United States)

    Condon, Christopher; Clifford, Matthew

    2010-01-01

    This brief reviews the publicly available principal assessments and points superintendents and policy makers toward strong instruments to measure principal performance. Specifically, the measures included in this review are expressly intended to evaluate principal performance and have varying degrees of publicly available evidence of psychometric…

  12. Arsenic mobility and speciation in contaminated kitchen garden and lawn soils: an evaluation of water for assessment of As phytoavailability.

    Science.gov (United States)

    Waterlot, Christophe; Douay, Francis

    2015-04-01

    Emissions from primary lead smelters have been recognized as one of the mainly factor which has contributed to the contamination of soils by metals. Less attention has been paid to volatile metalloids such as arsenic (As) which accompanies lead (Pb) smelting activities. One of the objectives of this study was to determine the As concentrations in various extracting solutions using a collection of urban soils located no far away from two former Pb and zinc plants in the North of France. The procedure for the determination of As, As(III), and As(V) with hydride vapor generator atomic absorption spectrometry was described in details. Pseudo-total concentrations of As in the studied soils ranged from 5.3 to 65.9 mg kg(-1). Good correlations were found between As and lead, zinc, and cadmium concentrations in soils. These depended on the soil uses and the soil distance from the source of contamination. Because the form of As may pose a health risk to human population, its speciation was determined in each urban top soils. Very good correlations were found between As(III) and As(V) versus As concentrations in soils studied, but the results did no permit to establish a relation between the location of soils and their uses. In contrast, it was shown that the highest mobility factor and lowest partitioning index values were related to the location. The mobilty of As depended on the assimilated phosphorus (P), carbonate contents, and pH. The percentages of the water-extractable As concentrations ranged from 0.3 to 3.0% of the As concentrations in soils. Very good positive correlations between water-extractable As(III) and As(V) versus water-extractable As concentrations were obtained. It was shown that the water-extractable As(III) concentrations depended on the soil uses. The results revealed that soils for which the As was the most mobile presented the highest water-extractable As concentrations. Principal component analysis indicated that mechanisms related to the release

  13. k-t PCA: temporally constrained k-t BLAST reconstruction using principal component analysis

    DEFF Research Database (Denmark)

    Pedersen, Henrik; Kozerke, Sebastian; Ringgaard, Steffen

    2009-01-01

    in applications exhibiting a broad range of temporal frequencies such as free-breathing myocardial perfusion imaging. We show that temporal basis functions calculated by subjecting the training data to principal component analysis (PCA) can be used to constrain the reconstruction such that the temporal resolution...... is improved. The presented method is called k-t PCA....

  14. Influence of extractable soil manganese on oxidation capacity of different soils in Korea

    Science.gov (United States)

    Chon, Chul-Min; Kim, Jae Gon; Lee, Gyoo Ho; Kim, Tack Hyun

    2008-08-01

    We examined the relationship between soil oxidation capacity and extractable soil manganese, iron oxides, and other soil properties. The Korean soils examined in this study exhibited low to medium Cr oxidation capacities, oxidizing 0.00-0.47 mmol/kg, except for TG-4 soils, which had the highest capacity for oxidizing added Cr(III) [>1.01 mmol/kg of oxidized Cr(VI)]. TG and US soils, with high Mn contents, had relatively high oxidation capacities. The Mn amounts extracted by dithionite-citrate-bicarbonate (DCB) (Mnd), NH2OH·HCl (Mnh), and hydroquinone (Mnr) were generally very similar, except for the YS1 soils, and were well correlated. Only small proportions of either total Mn or DCB-extractable Mn were extracted by NH2OH·HCl and hydroquinone in the YS1 soils, suggesting inclusion of NH2OH·HCl and hydroquinone-resistant Mn oxides, because these extractants are weaker reductants than DCB. No Cr oxidation test results were closely related to total Mn concentrations, but Mnd, Mnh, and Mnr showed a relatively high correlation with the Cr tests ( r = 0.655-0.851; P Mnh were better correlated with the Cr oxidation tests than was the Mnr concentration, suggesting that the oxidation capacity of our soil samples can be better explained by Mnd and Mnh than by Mnr. The first component in principal components analysis indicated that extractable soil Mn was a main factor controlling net Cr oxidation in the soils. Total soil Mn, Fe oxides, and the clay fraction are crucial for predicting the mobility of pollutants and heavy metals in soils. The second principal component indicated that the presence of Fe oxides in soils had a significant relationship with the clay fraction and total Mn oxide, and was also related to heavy-metal concentrations (Zn, Cd, and Cu, but not Pb).

  15. Tonopah Test Range - Index

    Science.gov (United States)

    Capabilities Test Operations Center Test Director Range Control Track Control Communications Tracking Radars Photos Header Facebook Twitter YouTube Flickr RSS Tonopah Test Range Top TTR_TOC Tonopah is the testing range of choice for all national security missions. Tonopah Test Range (TTR) provides research and

  16. Record of principal work activities/deliverables

    International Nuclear Information System (INIS)

    1989-09-01

    Over the five year period of performance, thirteen task assignments were issued by the DOE to ARINC Research. During the two year base period seven tasks were assigned. Two task assignments were issued for each of the three consecutive one year option periods. Associated with all task assignments were multiple subtasks, some of which required significant effort. These subtasks are appropriately cited in this report under their respective task assignments as principal work activities or deliverables. The technical and management support provided to the DOE under this contract focused on two general areas: (1) appraisal activities and (2) non-appraisal activities. Support to appraisals included planning, document review, developing lines-of-inquiry, interviewing, data collection, report writing, and follow-up. Such work was executed both on-site at the DOE facility under review and off-site. Non-appraisal support was varied and included such areas as document review, data base development, technical assessments. statistical analysis, policy analysis, reliability engineering, and workshop and conference planning and execution

  17. Physicochemical Characteristics and Heavy Metal Levels in Soil ...

    African Journals Online (AJOL)

    ADOWIE PERE

    weathering of mineral; the anthropogenic sources are associated mainly with ... al., 2013 reported high levels of Cd, Zn, Ni, Cr and. Pb from soil .... Determination of trace elements (Zn and Mn): 5 g of the dried ..... vehicles constitute principal source of Pb. Lead ..... Interaction between metals and soil organic matter in various.

  18. The soil-water characteristic curve at low soil-water contents: Relationships with soil specific surface area and texture

    DEFF Research Database (Denmark)

    Resurreccion, A C; Møldrup, Per; Tuller, M

    2011-01-01

    dominate over capillary forces, have also been used to estimate soil specific surface area (SA). In the present study, the dry end of the SWRC was measured with a chilled-mirror dew point psychrometer for 41 Danish soils covering a wide range of clay (CL) and organic carbon (OC) contents. The 41 soils were...

  19. Bioavailability of radiocaesium in soil: parameterization using soil characteristics

    Energy Technology Data Exchange (ETDEWEB)

    Syssoeva, A.A.; Konopleva, I.V. [Russian Institute of Agricultural Radiology and Agroecology, Obninsk (Russian Federation)

    2004-07-01

    It has been shown that radiocaesium availability to plants strongly influenced by soil properties. For the best evaluation of TFs it necessary to use mechanistic models that predict radionuclide uptake by plants based on consideration of sorption-desorption and fixation-remobilization of the radionuclide in the soil as well as root uptake processes controlled by the plant. The aim of the research was to characterise typical Russian soils on the basis of the radiocaesium availability. The parameter of the radiocaesium availability in soils (A) has been developed which consist on radiocaesium exchangeability; CF -concentration factor which is the ratio of the radiocaesium in plant to that in soil solution; K{sub Dex} - exchangeable solid-liquid distribution coefficient of radiocaesium. The approach was tested for a wide range of Russian soils using radiocaesium uptake data from a barley pot trial and parameters of the radiocaesium bioavailability. Soils were collected from the arable horizons in different soil climatic zones of Russia and artificially contaminated by {sup 137}Cs. The classification of soils in terms of the radiocaesium availability corresponds quite well to observed linear relationship between {sup 137}Cs TF for barley and A. K{sub Dex} is related to the soil radiocaesium interception potential (RIP), which was found to be positively and strongly related to clay and physical clay (<0,01 mm) content. The {sup 137}Cs exchangeability were found to be in close relation to the soil vermiculite content, which was estimated by the method of Cs{sup +} fixation. It's shown radiocaesium availability to plants in soils under study can be parameterized through mineralogical soil characteristics: % clay and the soil vermiculite content. (author)

  20. The organic contamination level based on the total soil mass is not a proper index of the soil contamination intensity

    Science.gov (United States)

    Hung, H.-W.; Daniel, Sheng G.; Lin, T.-F.; Su, Y.; Chiou, C.T.

    2009-01-01

    Concentrations of organic contaminants in common productive soils based on the total soil mass give a misleading account of actual contamination effects. This is attributed to the fact that productive soils are essentially water-saturated, with the result that the soil uptake of organic compounds occurs principally by partition into the soil organic matter (SOM). This report illustrates that the soil contamination intensity of a compound is governed by the concentration in the SOM (Com) rather than by the concentration in whole soil (Cs). Supporting data consist of the measured levels and toxicities of many pesticides in soils of widely differing SOM contents and the related levels in in-situ crops that defy explanation by the Cs values. This SOM-based index is timely needed for evaluating the contamination effects of food crops grown in different soils and for establishing a dependable priority ranking for intended remediation of numerous contamination sites.

  1. 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.

  2. SoilGrids1km — Global Soil Information Based on Automated Mapping

    Science.gov (United States)

    Hengl, Tomislav; de Jesus, Jorge Mendes; MacMillan, Robert A.; Batjes, Niels H.; Heuvelink, Gerard B. M.; Ribeiro, Eloi; Samuel-Rosa, Alessandro; Kempen, Bas; Leenaars, Johan G. B.; Walsh, Markus G.; Gonzalez, Maria Ruiperez

    2014-01-01

    Background Soils are widely recognized as a non-renewable natural resource and as biophysical carbon sinks. As such, there is a growing requirement for global soil information. Although several global soil information systems already exist, these tend to suffer from inconsistencies and limited spatial detail. Methodology/Principal Findings We present SoilGrids1km — a global 3D soil information system at 1 km resolution — containing spatial predictions for a selection of soil properties (at six standard depths): soil organic carbon (g kg−1), soil pH, sand, silt and clay fractions (%), bulk density (kg m−3), cation-exchange capacity (cmol+/kg), coarse fragments (%), soil organic carbon stock (t ha−1), depth to bedrock (cm), World Reference Base soil groups, and USDA Soil Taxonomy suborders. Our predictions are based on global spatial prediction models which we fitted, per soil variable, using a compilation of major international soil profile databases (ca. 110,000 soil profiles), and a selection of ca. 75 global environmental covariates representing soil forming factors. Results of regression modeling indicate that the most useful covariates for modeling soils at the global scale are climatic and biomass indices (based on MODIS images), lithology, and taxonomic mapping units derived from conventional soil survey (Harmonized World Soil Database). Prediction accuracies assessed using 5–fold cross-validation were between 23–51%. Conclusions/Significance SoilGrids1km provide an initial set of examples of soil spatial data for input into global models at a resolution and consistency not previously available. Some of the main limitations of the current version of SoilGrids1km are: (1) weak relationships between soil properties/classes and explanatory variables due to scale mismatches, (2) difficulty to obtain covariates that capture soil forming factors, (3) low sampling density and spatial clustering of soil profile locations. However, as the Soil

  3. SoilGrids1km--global soil information based on automated mapping.

    Directory of Open Access Journals (Sweden)

    Tomislav Hengl

    Full Text Available BACKGROUND: Soils are widely recognized as a non-renewable natural resource and as biophysical carbon sinks. As such, there is a growing requirement for global soil information. Although several global soil information systems already exist, these tend to suffer from inconsistencies and limited spatial detail. METHODOLOGY/PRINCIPAL FINDINGS: We present SoilGrids1km--a global 3D soil information system at 1 km resolution--containing spatial predictions for a selection of soil properties (at six standard depths: soil organic carbon (g kg-1, soil pH, sand, silt and clay fractions (%, bulk density (kg m-3, cation-exchange capacity (cmol+/kg, coarse fragments (%, soil organic carbon stock (t ha-1, depth to bedrock (cm, World Reference Base soil groups, and USDA Soil Taxonomy suborders. Our predictions are based on global spatial prediction models which we fitted, per soil variable, using a compilation of major international soil profile databases (ca. 110,000 soil profiles, and a selection of ca. 75 global environmental covariates representing soil forming factors. Results of regression modeling indicate that the most useful covariates for modeling soils at the global scale are climatic and biomass indices (based on MODIS images, lithology, and taxonomic mapping units derived from conventional soil survey (Harmonized World Soil Database. Prediction accuracies assessed using 5-fold cross-validation were between 23-51%. CONCLUSIONS/SIGNIFICANCE: SoilGrids1km provide an initial set of examples of soil spatial data for input into global models at a resolution and consistency not previously available. Some of the main limitations of the current version of SoilGrids1km are: (1 weak relationships between soil properties/classes and explanatory variables due to scale mismatches, (2 difficulty to obtain covariates that capture soil forming factors, (3 low sampling density and spatial clustering of soil profile locations. However, as the SoilGrids system is

  4. Assessment of polycyclic aromatic hydrocarbons (PAHs) pollution in soil of suburban areas in Tianjin, China.

    Science.gov (United States)

    Lv, Jungang; Shi, Rongguang; Cai, Yanming; Liu, Yong

    2010-07-01

    Soil contamination with polycyclic aromatic hydrocarbons is an increasing problem and has aroused more and more concern in many countries, including China. In this study, representative soil samples (n = 87) of suburban areas in Tianjin (Xiqing, Dongli, Jinnan, Beichen) were evaluated for 16 polycyclic aromatic hydrocarbons. Surface soil samples were air-dried and sieved. Microwave assisted extraction was used for polycyclic aromatic hydrocarbons preparation prior to analysis with gas chromatography-mass spectrometry. The total concentrations of tested polycyclic aromatic hydrocarbons in Xiqing, Dongli, Jinnan, Beichen ranged in 58.5-2,748.3, 36.1-6,734.7, 58.5-4,502.5, 29.7-852.5 ng/g and the averages of total concentration of polycyclic aromatic hydrocarbons were 600.5, 933.6, 640.8, 257.3 ng/g, respectively. Spatial variation of polycyclic aromatic hydrocarbons in soil was illustrated; Pollution status and comparison to other cities were also investigated. Serious polycyclic aromatic hydrocarbons soil pollution was found in Dongli district, on the contrary, Bap in most sites in Beichen did not exceed relative standards and most sites in Beichen should be classified as non-contaminated soil. Principal component analysis was used to identify the possible sources of different districts. It turned out that coal combustion still was the most important sources in three districts except Beichen. Coking, traffic, cooking, biomass combustion also accounted for polycyclic aromatic hydrocarbons pollution to certain extent in different districts. These data can be further used to assess the health risk associated with soils polluted with polycyclic aromatic hydrocarbons and help local government find proper way to reduce polycyclic aromatic hydrocarbons pollution in soils.

  5. Pedotransfer functions estimating soil hydraulic properties using different soil parameters

    DEFF Research Database (Denmark)

    Børgesen, Christen Duus; Iversen, Bo Vangsø; Jacobsen, Ole Hørbye

    2008-01-01

    Estimates of soil hydraulic properties using pedotransfer functions (PTF) are useful in many studies such as hydrochemical modelling and soil mapping. The objective of this study was to calibrate and test parametric PTFs that predict soil water retention and unsaturated hydraulic conductivity...... parameters. The PTFs are based on neural networks and the Bootstrap method using different sets of predictors and predict the van Genuchten/Mualem parameters. A Danish soil data set (152 horizons) dominated by sandy and sandy loamy soils was used in the development of PTFs to predict the Mualem hydraulic...... conductivity parameters. A larger data set (1618 horizons) with a broader textural range was used in the development of PTFs to predict the van Genuchten parameters. The PTFs using either three or seven textural classes combined with soil organic mater and bulk density gave the most reliable predictions...

  6. Soil Erosion and Agricultural Sustainability

    Science.gov (United States)

    Montgomery, D. R.

    2009-04-01

    Data drawn from a global compilation of studies support the long articulated contention that erosion rates from conventionally plowed agricultural fields greatly exceed rates of soil production, erosion under native vegetation, and long-term geological erosion. Whereas data compiled from around the world show that soil erosion under conventional agriculture exceeds both rates of soil production and geological erosion rates by up to several orders of magnitude, similar global distributions of soil production and geological erosion rates suggest an approximate balance. Net soil erosion rates in conventionally plowed fields on the order of 1 mm/yr can erode typical hillslope soil profiles over centuries to millennia, time-scales comparable to the longevity of major civilizations. Well-documented episodes of soil loss associated with agricultural activities date back to the introduction of erosive agricultural methods in regions around the world, and stratigraphic records of accelerated anthropogenic soil erosion have been recovered from lake, fluvial, and colluvial stratigraphy, as well as truncation of soil stratigraphy (such as truncated A horizons). A broad convergence in the results from studies based on various approaches employed to study ancient soil loss and rates of downstream sedimentation implies that widespread soil loss has accompanied human agricultural intensification in examples drawn from around the world. While a broad range of factors, including climate variability and society-specific social and economic contexts — such as wars or colonial relationships — all naturally influence the longevity of human societies, the ongoing loss of topsoil inferred from studies of soil erosion rates in conventional agricultural systems has obvious long-term implications for agricultural sustainability. Consequently, modern agriculture — and therefore global society — faces a fundamental question over the upcoming centuries. Can an agricultural system

  7. Transformers as a potential for soil contamination

    Directory of Open Access Journals (Sweden)

    N. Stojić

    2014-10-01

    Full Text Available The aim of this paper is to investigate the presence of PCBs and heavy metals in the surrounding soil and also in the soil of the receiving pit located below the PCB contaminated transformer. Concentrations of PCBs in our samples are ranged from 0,308 to 0,872 mg/kg of absolutely dry soil.

  8. Predicting radiocaesium sorption characteristics with soil chemical properties for Japanese soils.

    Science.gov (United States)

    Uematsu, Shinichiro; Smolders, Erik; Sweeck, Lieve; Wannijn, Jean; Van Hees, May; Vandenhove, Hildegarde

    2015-08-15

    The high variability of the soil-to-plant transfer factor of radiocaesium (RCs) compels a detailed analysis of the radiocaesium interception potential (RIP) of soil, which is one of the specific factors ruling the RCs transfer. The range of the RIP values for agricultural soils in the Fukushima accident affected area has not yet been fully surveyed. Here, the RIP and other major soil chemical properties were characterised for 51 representative topsoils collected in the vicinity of the Fukushima contaminated area. The RIP ranged a factor of 50 among the soils and RIP values were lower for Andosols compared to other soils, suggesting a role of soil mineralogy. Correlation analysis revealed that the RIP was most strongly and negatively correlated to soil organic matter content and oxalate extractable aluminium. The RIP correlated weakly but positively to soil clay content. The slope of the correlation between RIP and clay content showed that the RIP per unit clay was only 4.8 mmol g(-1) clay, about threefold lower than that for clays of European soils, suggesting more amorphous minerals and less micaceous minerals in the clay fraction of Japanese soils. The negative correlation between RIP and soil organic matter may indicate that organic matter can mask highly selective sorption sites to RCs. Multiple regression analysis with soil organic matter and cation exchange capacity explained the soil RIP (R(2)=0.64), allowing us to map soil RIP based on existing soil map information. Copyright © 2015 Elsevier B.V. All rights reserved.

  9. 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...

  10. Hydrology and soil erosion

    Science.gov (United States)

    Leonard J. Lane; Mary R. Kidwell

    2003-01-01

    We review research on surface water hydrology and soil erosion at the Santa Rita Experimental Range (SRER). Almost all of the research was associated with eight small experimental watersheds established from 1974 to 1975 and operated until the present. Analysis of climatic features of the SRER supports extending research findings from the SRER to broad areas of the...

  11. Soil Mechanics

    OpenAIRE

    Verruijt, A.

    2010-01-01

    This book is the text for the introductory course of Soil Mechanics in the Department of Civil Engineering of the Delft University of Technology, as I have given from 1980 until my retirement in 2002. It contains an introduction into the major principles and methods of soil mechanics, such as the analysis of stresses, deformations, and stability. The most important methods of determining soil parameters, in the laboratory and in situ, are also described. Some basic principles of applied mecha...

  12. Distribution of heavy metals in cocoa farm soils in the Western Region of Ghana

    International Nuclear Information System (INIS)

    Ackah, Justice Edusei

    2012-10-01

    Western Region is the largest cocoa producer in Ghana. Cocoa farmlands have over the past decades received heavy doses of agrochemical application to boost cocoa production. These agrochemicals, however, may contain heavy metals and it is therefore likely that the metals may have accumulated in the soils. Evaluating the total concentrations and understanding the distribution characteristics of heavy metals in cocoa growing soils can aid environmental managers and even help regulate the rate of agrochemical application. A study was therefore, carried out on some selected soils of major cocoa growing areas in Western Region of Ghana to determine the levels of cadmium (Cd), chromium (Cr), copper (Cu), iron (Fe), manganese (Mn), nickel (Ni), lead (Pb) and zinc (Zn) in the soils and also to determine some of the soil factors that control the distribution of the heavy metals in the soil. Eight soils (two Haplic Luvisols, three Ferric Acrisols, one Haplic Ferrasol and two Dystric Fluvisols) and their accompanying pristine soils as control were taken from adjacent natural forests sampled at depths of 0 – 10 cm, 10 – 30 cm, 30 – 50 cm, 50 – 80 cm and 80 – 100 cm. These soils were analysed for their particle size distribution, pH, organic carbon, cation exchange capacity, exchangeable bases, and total and bio-available Cd, Cr, Cu, Fe, Mn, Ni, Pb and Zn. The study indicated that the ΔpH which is pH_K_C_l – pH_H_2_O were all negative indicating that the soils generally had net negative charges on their colloidal surface. For all soils, clay content and pH increased with depth indicating co-migration of the two soil parameters whilst total organic carbon content decreased with depth. Cation exchange capacity, however, did not show any clear pattern with depth in the soils. The average abundance of heavy metals determined in these soils decreased as follows: Fe > Mn > Cr > Zn > Cu > Cd > Pb > Ni. The soils had low metal contents, less than or within the range of

  13. Soil management planning for military installations: Strategy for identifying contaminated soils

    International Nuclear Information System (INIS)

    Makdisi, R.S.; Baskin, D.A.; Downey, D.; Taffinder, S.A.

    1992-01-01

    Numerous federal and state regulations mandate the proper handling and disposal and/or treatment of contaminated soils. The Land Disposal Ban and the increasing lack of new or proximal land disposal facilities, coupled with the increasing liability of off-site disposal, have created a need for altering the traditional methods of managing contaminated sods. To delineate soil management decisions, a Soil Management Plan (SMP) was developed which incorporates the substantive requirements of CERCLA/SARA and RCRA into the ongoing base activities (i.e., construction projects, utility repairs and maintenance) and other environmental projects (i.e., underground storage tank removals) that may involve contaminated soils. The decision-making process is developed to guide base personnel in recognizing contamination, following proper sampling and temporary storage procedures, preventing unnecessary human exposure and isolating soils for removal off-site or treatment on-site. The SMP also contains a comprehensive review of soil remediation technologies, such as biological treatment, soil vapor extraction, soil washing, biofiltering, thermal desorption, soil stabilization/solidification, chemical/physical treatment and incineration. Contaminant types expected at the federal military facility are cross-referenced to the appropriate remediation technologies to determine the specific base needs for a soil treatment unit. An example of a conceptual design for a hydrocarbon-contaminated soil treatment unit is presented for a base where underground fuel tanks are the principal source of soil contamination

  14. Soil diversity and hydration as observed by ChemCam at Gale Crater, Mars

    NARCIS (Netherlands)

    Meslin, P.-Y.; Gasnault, O.; Forni, O.; Schröder, S.; Cousin, A.; Berger, G.; Clegg, S.M.; Lasue, J.; Maurice, S.; Sautter, V.; Le Mouélic, S.; Wiens, R.C.; Fabre, C.; Goetz, W.; Bish, D.; Mangold, N.; Ehlmann, B.; Lanza, N.; Harri, A.-M.; Anderson, R.; Rampe, E.; McConnochie, T.H.; Pinet, P.; Blaney, D.; Léveillé, R.; Archer, D.; Barraclough, B.; Bender, S.; Blake, D.; Blank, J.G.; Bridges, N.; Clark, B.C.; DeFlores, L.; Delapp, D.; Dromart, G.; Dyar, M.D.; Fisk, M.; Gondet, B.; Grotzinger, J.; Herkenhoff, K.; Johnson, J.; Lacour, J.-L.; Langevin, Y.; Leshin, L.; Lewin, E.; Madsen, M.B.; Melikechi, N.; Mezzacappa, A.; Mischna, M.A.; Moores, J.E.; Newsom, H.; Ollila, A.; Perez, R.; Renno, N.; Sirven, J.-B.; Tokar, R.; De La Torre, M.; D'Uston, L.; Vaniman, D.; Yingst, A.; MSL Science Team, the

    2013-01-01

    The ChemCam instrument, which provides insight into martian soil chemistry at the submillimeter scale, identified two principal soil types along the Curiosity rover traverse: a fine-grained mafic type and a locally derived, coarse-grained felsic type. The mafic soil component is representative of

  15. Transuranic behavior in soils and plants

    International Nuclear Information System (INIS)

    Wildung, R.E.; Garland, T.R.; Cataldo, D.A.; Rogers, J.E.; McFadden, K.M.; Jenne, E.A.; Schreckhise, R.G.

    1981-01-01

    The principal objective of this study is to gather information about soil, plant, and foliar interaction factors that influence the availability of transuranics to agricultural plants and animals. This paper discusses plant processes which influence transport across the plant root membrane and foliar surfaces, and the form and sites of deposition of transuranic elements in mature plants

  16. A multivariate analysis of intrinsic soil components influencing the mean-weight diameter of water-stable aggregates

    International Nuclear Information System (INIS)

    Mbagwu, J.S.C.; Chukwu, W.I.E.

    1994-06-01

    A knowledge of the soil properties influencing the water-stability of soil aggregates is needed for selecting those more easily-determined properties that would be useful in areas where lack of facilities makes its direct determination impossible. In this laboratory study we evaluated the main soil physical, chemical and mineralogical properties influencing the stability of macro aggregates of some Italian surface soils in water. The objective is to select a subset of soil properties which predict optimally, soil aggregate stability. The index of stability used is the mean weight diameter of water-stable aggregates whereas the method of evaluation is the principal component analysis (PCA). The range in coefficients of variation (CV) among the properties was least in the physical (12.0-61.0%), medium in the mineralogical (28.0-116.2%) and highest in the chemical (8.2-110.8%) properties. The wider the range in CV in each subset of properties, the greater the number of components extracted by the PCA. The component defining variables, i.e. those with the highest loadings on each component and therefore, provide the best relationship between the variables and aggregate stability, revealed the ratio of total sand/clay and plastic limit as the significant physical properties. The significant chemical properties are Al 2 O 3 , FeO, MgO and MnO which contribute positively to aggregate stability. Feldspar, quartz and muscovite are the significant mineralogical properties each of which is negatively related to aggregate stability. These soil components are useful for developing empirical models for estimating the stability of aggregates of these soils in water. (author). 38 refs, 7 tabs

  17. Implementation of the geoethics principal to environmental technologies by Biogeosystem Technique

    Science.gov (United States)

    Batukaev, Abdulmalik; Kalinitchenko, Valery; Minkina, Tatiana; Mandzhieva, Saglara; Sushkova, Svetlana

    2017-04-01

    The uncertainty and degradation of biosphere is a result of outdated industrial technologies. The incorrect principals of the nature resources use paradigm are to be radically changed corresponding to principals of Geoethics. Technological dead-end is linked to Philosophy of Technology. The organic protection and imitation of natural patterns are till now the theoretical base of technology. The technological and social determinism are proposed as the "inevitable" for humankind. One is forced to believe that the only way for humanity is to agree that the outdated way of technical development is the only possibility for humankind to survive. But rough imitation as a method of outdated technological platform is fruitless now. Survival under practice of industrial technology platform now has become extremely dangerous. The challenge for humanity is to overcome the chain of environmental hazards of agronomy, irrigation, industry, and other human activities in biosphere, which awkwardly imitate the natural processes: plowing leads to degradation of soil and greenhouse gases emission; irrigation leads to excessive moistening and degradation of soil, landscape, greenhouse gases emission, loss of freshwater - the global deficit; waste utilization leads to greenhouse gases emission, loss of oxigen and other ecological hazards. The fundamentally new technologies are to be generates for development of biosphere, food and resources renewing. Aristotle told that technique can go beyond nature and implement "what nature can't bring to a finish." To overcome fundamental shortcomings of industrial technologies, incorrect land use we propose the Biogeosystem Technique (BGT*) for biosphere sustainability. The BGT* key point is transcendent approach (not imitating of the natural processes) - new technical solutions for biosphere - soil construction, the fluxes of energy, matter, and water control and biological productivity of terrestrial systems. Intra-soil milling which provides the

  18. 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...... and B plots were placed in a mixed sequence (C-B-C-B-C-B-C-B) and at the same time the eight plots formed a natural pH gradient ranging from pH 7.7 to 6.3. We determined bulk density, saturated hydraulic conductivity (K-sat), soil water retention characteristics, soil-air permeability, and soil...

  19. Using 137 Cs measurements to investigate the influence of erosion and soil redistribution on soil properties.

    Science.gov (United States)

    Du, P; Walling, D E

    2011-05-01

    Information on the interaction between soil erosion and soil properties is an important requirement for sustainable management of the soil resource. The relationship between soil properties and the soil redistribution rate, reflecting both erosion and deposition, is an important indicator of this interaction. This relationship is difficult to investigate using traditional approaches to documenting soil redistribution rates involving erosion plots and predictive models. However, the use of the fallout radionuclide (137)Cs to document medium-term soil redistribution rates offers a means of overcoming many of the limitations associated with traditional approaches. The study reported sought to demonstrate the potential for using (137)Cs measurements to assess the influence of soil erosion and redistribution on soil properties (particle size composition, total C, macronutrients N, P, K and Mg, micronutrients Mn, Mo, Fe, Cu and Zn and other elements, including Ti and As). (137)Cs measurements undertaken on 52 soil cores collected within a 7 ha cultivated field located near Colebrooke in Devon, UK were used to establish the magnitude and spatial pattern of medium-term soil redistribution rates within the field. The soil redistribution rates documented for the individual sampling points within the field ranged from an erosion rate of -12.9 t ha(-1) yr(-1) to a deposition rate of 19.2 t ha(-1) yr(-1). Composite samples of surface soil (0-5 cm) were collected immediately adjacent to each coring point and these samples were analysed for a range of soil properties. Individual soil properties associated with these samples showed significant variability, with CV values generally lying in the range 10-30%. The relationships between the surface soil properties and the soil redistribution rate were analysed. This analysis demonstrated statistically significant relationships between some soil properties (total phosphorus, % clay, Ti and As) and the soil redistribution rate, but for

  20. Using 137Cs measurements to investigate the influence of erosion and soil redistribution on soil properties

    International Nuclear Information System (INIS)

    Du, P.; Walling, D.E.

    2011-01-01

    Information on the interaction between soil erosion and soil properties is an important requirement for sustainable management of the soil resource. The relationship between soil properties and the soil redistribution rate, reflecting both erosion and deposition, is an important indicator of this interaction. This relationship is difficult to investigate using traditional approaches to documenting soil redistribution rates involving erosion plots and predictive models. However, the use of the fallout radionuclide 137 Cs to document medium-term soil redistribution rates offers a means of overcoming many of the limitations associated with traditional approaches. The study reported sought to demonstrate the potential for using 137 Cs measurements to assess the influence of soil erosion and redistribution on soil properties (particle size composition, total C, macronutrients N, P, K and Mg, micronutrients Mn, Mo, Fe, Cu and Zn and other elements, including Ti and As). 137 Cs measurements undertaken on 52 soil cores collected within a 7 ha cultivated field located near Colebrooke in Devon, UK were used to establish the magnitude and spatial pattern of medium-term soil redistribution rates within the field. The soil redistribution rates documented for the individual sampling points within the field ranged from an erosion rate of -12.9 t ha -1 yr -1 to a deposition rate of 19.2 t ha -1 yr -1 . Composite samples of surface soil (0-5 cm) were collected immediately adjacent to each coring point and these samples were analysed for a range of soil properties. Individual soil properties associated with these samples showed significant variability, with CV values generally lying in the range 10-30%. The relationships between the surface soil properties and the soil redistribution rate were analysed. This analysis demonstrated statistically significant relationships between some soil properties (total phosphorus, % clay, Ti and As) and the soil redistribution rate, but for most

  1. Computing Cumulative Interest and Principal Paid For a Calendar Year

    OpenAIRE

    John O. MASON

    2011-01-01

    This paper demonstrates how easy it is use Microsoft Excel’s CUMPRINC and CUMIPMT functions to compute principal and interest paid for an entire year, even though the payments were made monthly. The CUMPRINC function computes the principal paid by a series of loan payments; the CUMIPMT function computes the interest paid. These two functions provide an alternative to preparing a monthly loan amortization schedule and adding up the amounts of monthly interest paid and principal paid for the ye...

  2. Soil Solution

    NARCIS (Netherlands)

    Sonneveld, C.; Voogt, W.

    2009-01-01

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

  3. Principal succession: The socialisation of a primary school principal in South Africa

    Directory of Open Access Journals (Sweden)

    Gertruida M. Steyn

    2013-04-01

    Full Text Available This study focussed on the socialisation of a new principal in a South African primary school with a strong Christian culture. He was appointed when the predecessor retired after more than two decades. The conceptual framework focuses on the three phases of socialisation: professional socialisation, organisational socialisation and occupational identity, which are used to interpret the study. A qualitative study, which occurred during two phases, investigated the phenomenon, principal succession, in the particular school. The data collection methods included a number of interviews with the principal, a focus group interview with staff members who experienced the previous principal’s leadership practice, and individual interviews with staff members. The following categories emerged from the data analysis: Recalling the previous principal: ‘One sees Mr X [the predecessor] everywhere’; Entry and orientation: ‘I found it intimidating initially’; and Immersion and reshaping: ‘Reins that previously were a bit slack, he is now pulling tight’.Die sosialisering van ’n primêre skoolhoof in Suid-Afrika. Hierdie studie het gefokus op die sosialisering van ’n nuwe skoolhoof in ’n Suid-Afrikaanse primêre skool met ’n sterk Christelike kultuur. Hy is aangestel toe sy voorganger ná meer as twee dekades afgetree het. Die konseptuele raamwerk, wat gebruik is om die bevindinge te interpreteer, het op die drie fases van sosialisering gefokus, naamlik professionele sosialisering, organisatoriese sosialisering en beroepsidentiteit. ’n Kwalitatiewe ondersoek na die skoolhoofopvolgingverskynsel in die bepaalde skool is in twee fases gedoen. Die data-insamelingsmetodes het ’n aantal onderhoude met die skoolhoof, ’n fokusgroeponderhoud met personeellede wat ook onder leierskap van die vorige skoolhoof gewerk het en individuele onderhoude met personeellede ingesluit. Tydens die data-analise het die volgende kategorieë na vore gekom

  4. Testing of multistep soil washing for radiocesium-contaminated soil containing plant matter

    International Nuclear Information System (INIS)

    Funakawa, Masafumi; Tagawa, Akihiro; Okuda, Nobuyasu

    2012-01-01

    Decontamination work following radiocesium exposure requires a vast reduction in the amount of contaminated soil generated. The current study subjected 4 types of contaminated soil with different properties to multistep soil washing under the same conditions. This study also determined the effectiveness of radiocesium decontamination and the extent to which the amount of contaminated soil was reduced. In addition, the effectiveness of plant matter separation, adsorbent addition, and grinding as part of multistep soil washing was determined using the same contaminated soil. Results of testing indicated that the rate of radiocesium decontamination ranged from 73.6 to 89.2% and the recovery rate ranged from 51.5 to 84.2% for twice-treated soil, regardless of the soil properties or cesium level. Plant matter in soil had a high radiocesium level. However, there was little plant matter in our soil sample. Therefore, plant matter separation had little effect on the improvement in the percentage of radiocesium decontamination of twice-treated soil. Soil surface grinding improved the rate of radiocesium decontamination of twice-treated soil. However, radiocesium in soil tightly bound with minerals in the soil; thus, the addition of an adsorbent also failed to improve the rate of radiocesium decontamination. (author)

  5. Polybrominated diphenyl ethers in road and farmland soils from an e-waste recycling region in Southern China: Concentrations, source profiles, and potential dispersion and deposition

    International Nuclear Information System (INIS)

    Luo Yong; Luo Xiaojun; Lin Zhen; Chen Shejun; Liu Juan; Mai Bixian; Yang Zhongyi

    2009-01-01

    The present study analyzed road soils collected near the dismantling workshops of an e-waste recycling region in South China to determine the PBDE profiles. Farmland soils at a distance of about 2 km from the dismantling workshops were also collected to evaluate the potential dispersion and deposition of PBDEs in the surrounding environment. Total PBDE concentrations ranged from 191 to 9156 ng/g dry weight in road soils and from 2.9 to 207 ng/g dry weight in farmland soils, respectively. Three PBDE source profiles were observed from the road soils by principal component analysis, and were compared with the congener patterns in different technical products. Elevated abundances of octa- and nona-congeners were found in the 'deca-' derived PBDEs as compared with the deca-BDE products. The results in this study suggest that debromination of BDE 209 may have occurred during the use of electric and electronic equipment and/or another technical formulation (Bromkal 79-8DE) was also likely the source of octa- and nona-congeners in e-wastes. Comparison of the PBDE patterns in road and farmland soils implied that the PBDEs in farmland soils have been subject to complex environmental processes

  6. Distribution and Source Apportionment of Polycyclic Aromatic Hydrocarbons (PAHs) in Forest Soils from Urban to Rural Areas in the Pearl River Delta of Southern China

    Science.gov (United States)

    Xiao, Yihua; Tong, Fuchun; Kuang, Yuanwen; Chen, Bufeng

    2014-01-01

    The upper layer of forest soils (0–20 cm depth) were collected from urban, suburban, and rural areas in the Pearl River Delta of Southern China to estimate the distribution and the possible sources of polycyclic aromatic hydrocarbons (PAHs). Total concentrations of PAHs in the forest soils decreased significantly along the urban–suburban–rural gradient, indicating the influence of anthropogenic emissions on the PAH distribution in forest soils. High and low molecular weight PAHs dominated in the urban and rural forest soils, respectively, implying the difference in emission sources between the areas. The values of PAH isomeric diagnostic ratios indicated that forest soil PAHs were mainly originated from traffic emissions, mixed sources and coal/wood combustion in the urban, suburban and rural areas, respectively. Principal component analysis revealed that traffic emissions, coal burning and residential biomass combustion were the three primary contributors to forest soil PAHs in the Pearl River Delta. Long range transportation of PAHs via atmosphere from urban area might also impact the PAHs distribution in the forest soils of rural area. PMID:24599040

  7. Incremental Tensor Principal Component Analysis for Handwritten Digit Recognition

    Directory of Open Access Journals (Sweden)

    Chang Liu

    2014-01-01

    Full Text Available To overcome the shortcomings of traditional dimensionality reduction algorithms, incremental tensor principal component analysis (ITPCA based on updated-SVD technique algorithm is proposed in this paper. This paper proves the relationship between PCA, 2DPCA, MPCA, and the graph embedding framework theoretically and derives the incremental learning procedure to add single sample and multiple samples in detail. The experiments on handwritten digit recognition have demonstrated that ITPCA has achieved better recognition performance than that of vector-based principal component analysis (PCA, incremental principal component analysis (IPCA, and multilinear principal component analysis (MPCA algorithms. At the same time, ITPCA also has lower time and space complexity.

  8. HTO deposition by vapor exchange between atmosphere and soil

    International Nuclear Information System (INIS)

    Bunnenberg, C.

    1989-01-01

    HTO deposition to soils occurs by vapor exchange between atmosphere and soil-air, when the concentration gradient is directed downwards, and it is principally independent from simultaneous transport of H 2 O. In relatively dry top soil, which is frequently the case, as it tries to attain equilibrium with the air humidity, HTO diffuses into deeper soil driven by the same mechanisms that caused the deposition process. The resulting HTO profile is depending on the atmospheric supply and the soil physical conditions, and it is the source for further tritium pathways, namely root uptake by plants and reemission from soil back into the ground-level air. Simulation experiments with soil columns exposed to HTO labeled atmospheres have proved the theoretical expectation that under certain boundary conditions the HTO profile can be described by an error function. The key parameter is the effective diffusion coefficient, which in turn is a function of the sorption characteristics of the particular soil. (orig.) [de

  9. Speciation of zinc in contaminated soils

    International Nuclear Information System (INIS)

    Stephan, Chadi H.; Courchesne, Francois; Hendershot, William H.; McGrath, Steve P.; Chaudri, Amar M.; Sappin-Didier, Valerie; Sauve, Sebastien

    2008-01-01

    The chemical speciation of zinc in soil solutions is critical to the understanding of its bioavailability and potential toxic effects. We studied the speciation of Zn in soil solution extracts from 66 contaminated soils representative of a wide range of field conditions in both North America and Europe. Within this dataset, we evaluated the links among the dissolved concentrations of zinc and the speciation of Zn 2+ , soil solution pH, total soil Zn, dissolved organic matter (DOM), soil organic matter (SOM) and the concentrations of different inorganic anions. The solid-liquid partitioning coefficient (K d ) for Zn ranged from 17 to 13,100 L kg -1 soil. The fraction of dissolved Zn bound to DOM varied from 60% to 98% and the soil solution free Zn 2+ varied from 40% to 60% of the labile Zn. Multiple regression equations to predict free Zn 2+ , dissolved Zn and the solid-liquid partitioning of Zn are given for potential use in environmental fate modeling and risk assessment. The multiple regressions also highlight some of the most important soil properties controlling the solubility and chemical speciation of zinc in contaminated soils. - We studied the relationships among the chemical speciation of Zn in soil solution extracts from 66 contaminated soils and various physicochemical properties of the soils

  10. Transuranic element behavior in soils and plants

    International Nuclear Information System (INIS)

    Wildung, R.E.

    1982-01-01

    The principal objective of this study is to define soil, plant, and foliar interaction processes that influence the availability of transuranic elements to agricultural plants and animals as a basis for improved modeling and dose-assessment. Major areas of emphasis are: (1) soil and soil-microbial processes that influence the concentration and form of transuranic elements in soil solutions and availability to the plant root with time; (2) deposition and plant interception of airborne submicronic particles containing transuranic elements and their susceptibility to leaching; (3) plant processes that influence transport across plant root membrane and foliar surfaces, as well as the form and sites of deposition of transuranic elements in mature plants; and (4) the integrated effect of soil and plant processes on transuranic element availability to, and form in, animals that consume plants

  11. Dissipation of oxytetracycline in soils under different redox conditions

    International Nuclear Information System (INIS)

    Yang Jigeng; Ying Guangguo; Zhou Lijun; Liu Shan; Zhao Jianliang

    2009-01-01

    This study investigated the dissipation kinetics of oxytetracycline in soils under aerobic and anoxic conditions. Laboratory experiments showed that the dissipation of oxytetracycline in soil followed first-order reaction kinetics and its dissipation rates decreased with increasing concentration. Oxytetracycline dissipated faster in soil under aerobic conditions than under anoxic conditions. The half-lives for oxytetracycline in soil under aerobic conditions ranged between 29 and 56 days for non-sterile treatments and 99-120 days for sterile treatments, while under anoxic conditions the half-lives of oxytetracycline ranged between 43 and 62 days in the non-sterile soil and between 69 and 104 days in the sterile soil. This suggests microbes can degrade oxytetracycline in agricultural soil. Abiotic factors such as strong sorption onto soil components also played a role in the dissipation of oxytetracycline in soil. - Oxytetracycline dissipation in soils is influenced by redox conditions and soil properties.

  12. Dissipation of oxytetracycline in soils under different redox conditions

    Energy Technology Data Exchange (ETDEWEB)

    Jigeng, Yang [State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, 511 Kehua Street, Tianhe District, Guangzhou 510640 (China); Department of Chemistry and Chemical Engineering, Hunan University of Arts and Sciences, Changde 415000 (China); Ying Guangguo, E-mail: guangguo.ying@gmail.co [State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, 511 Kehua Street, Tianhe District, Guangzhou 510640 (China); Lijun, Zhou; Shan, Liu; Jianliang, Zhao [State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, 511 Kehua Street, Tianhe District, Guangzhou 510640 (China)

    2009-10-15

    This study investigated the dissipation kinetics of oxytetracycline in soils under aerobic and anoxic conditions. Laboratory experiments showed that the dissipation of oxytetracycline in soil followed first-order reaction kinetics and its dissipation rates decreased with increasing concentration. Oxytetracycline dissipated faster in soil under aerobic conditions than under anoxic conditions. The half-lives for oxytetracycline in soil under aerobic conditions ranged between 29 and 56 days for non-sterile treatments and 99-120 days for sterile treatments, while under anoxic conditions the half-lives of oxytetracycline ranged between 43 and 62 days in the non-sterile soil and between 69 and 104 days in the sterile soil. This suggests microbes can degrade oxytetracycline in agricultural soil. Abiotic factors such as strong sorption onto soil components also played a role in the dissipation of oxytetracycline in soil. - Oxytetracycline dissipation in soils is influenced by redox conditions and soil properties.

  13. Soil Forming Factors

    Science.gov (United States)

    It! What is Soil? Chip Off the Old Block Soil Forming Factors Matters of Life and Death Underneath It All Wise Choices A World of Soils Soil Forming Factors 2 A Top to Bottom Guide 3 Making a Soil Monolith 4 Soil Orders 5 State Soil Monoliths 6 Where in the Soil World Are You? >> A Top to

  14. What is Soil?

    Science.gov (United States)

    It! What is Soil? Chip Off the Old Block Soil Forming Factors Matters of Life and Death Underneath It All Wise Choices A World of Soils Soil? 2 The Skin of the Earth 3 Soil Ingredients 4 Soil Recipes 5 CLORPT for Short >> What Is Soil? Soils Make Life Plants grow in and from

  15. Soil Organic Matter to Soil Organic Carbon ratios in recovered mountain peatlands using Vis-Nir spectroscopy approach.

    Science.gov (United States)

    Fernandez, Susana del Carmen; Valderrabano, Jesus; Peon, Juan Jose; Bueno, Alvaro

    2015-04-01

    The present research is part of a Life Project title "Inland Wetlands North of the Iberian Peninsula: Management and restoration of wetlands and hygrophilous environments" TREMEDAL (LIFE 11/ENV/ES/707) in which 25 wetland sites distributed by Galicia, Asturias, Castilla and León, País Vasco and Navarra were selected to be protected, restore or improve their conservation status and store seeds of bog plant species in the gene bank of Atlantic Botanic Garden of Gijon City, Spain. In Cantabrian Mountain Range two Poldjes (Glacio-Karstic depressions) site in Picos de Europa National Park were selected to develop an experimental action in the framework of the Life project. The selected sites harboring the most biodiverse peatland plant communities in the Cantabrian Mountain Range thus are in danger of extinction due to overgrazing. The action proposes the exclusion of livestock and wild herbivores in 5 parcels in order to contrast the differences in evolution of plant communities, hydrology and soil organic matter between grazed and non-grazed areas; and to determine future management measures that can reconcile traditional livestock raising with a better conservation of peatlands. The peatland are Vega of Liordes (Castilla-Leon) at an average altitude of 1868 m and filled mainly by clayed ferruginous sediments and Vega of Comella (Principality of Asturias) at an average altitude of 850 m and filled by at least 49 m of glacial and lacustrine sediments and 8 m of necromass from peatland vegetation. The soils developed are histosols under seasonal hydric regime in which the phreatic level suffers fluctuations over 30 cm along the year. At the time 0 (time fences were) 45 samples of the upper 15 cm of the histosols inside and outside the fences were taken. At the time 1 ( one year later) were re-sampled. Total organic carbon (TOC), Oxidizable Organic Carbon (OC), Carbonates presence and pH were analysis by chemical procedures. Also the Vis-Nir spectral analysis of the

  16. Dynamical soil-structure interactions: influence of soil behaviour nonlinearities

    International Nuclear Information System (INIS)

    Gandomzadeh, Ali

    2011-01-01

    the soil and the response of the soil-structure system. Through these parametric studies we show that depending on the soil properties, frequency content of the soil response could change significantly due to the soil nonlinearity. The peaks of the transfer function between free field and outcropping responses shift to lower frequencies and amplification happens at this frequency range. Amplification reduction for the high frequencies and even de-amplification may happen for high level input motions. These changes influence the structural response. We show that depending on the combination of the fundamental frequency of the structure and the the natural frequency of the soil, the effect of soil-structure interaction could be significant or negligible. However, the effect of structure weight and rocking of the superstructure could change the results. Finally, the basin of Nice is used as an example of wave propagation on a heterogeneous nonlinear media and dynamic soil-structure interaction. The basin response is strongly dependent on the combination of soil nonlinearity, topographic effects and impedance contrast between soil layers. For the selected structures and soil profiles of this work, the performed numerical simulations show that the shift of the fundamental frequency is not a good index to discriminate linear from nonlinear soil behavior. (author)

  17. Compressive laser ranging.

    Science.gov (United States)

    Babbitt, Wm Randall; Barber, Zeb W; Renner, Christoffer

    2011-12-15

    Compressive sampling has been previously proposed as a technique for sampling radar returns and determining sparse range profiles with a reduced number of measurements compared to conventional techniques. By employing modulation on both transmission and reception, compressive sensing in ranging is extended to the direct measurement of range profiles without intermediate measurement of the return waveform. This compressive ranging approach enables the use of pseudorandom binary transmit waveforms and return modulation, along with low-bandwidth optical detectors to yield high-resolution ranging information. A proof-of-concept experiment is presented. With currently available compact, off-the-shelf electronics and photonics, such as high data rate binary pattern generators and high-bandwidth digital optical modulators, compressive laser ranging can readily achieve subcentimeter resolution in a compact, lightweight package.

  18. Dependence of Soil Respiration on Soil Temperature and Soil Moisture in Successional Forests in Southern China

    Institute of Scientific and Technical Information of China (English)

    Xu-Li Tang; Guo-Yi Zhou; Shu-Guang Liu; De-Qiang Zhang; Shi-Zhong Liu; Jiong Li; Cun-Yu Zhou

    2006-01-01

    The spatial and temporal variations in soil respiration and its relationship with biophysical factors in forests near the Tropic of Cancer remain highly uncertain. To contribute towards an improvement of actual estimates, soil respiration rates, soil temperature, and soil moisture were measured in three successional subtropical forests at the Dinghushan Nature Reserve (DNR) in southern China from March 2003 to February 2005. The overall objective of the present study was to analyze the temporal variations of soil respiration and its biophysical dependence in these forests. The relationships between biophysical factors and soil respiration rates were compared in successional forests to test the hypothesis that these forests responded similarly to biophysical factors. The seasonality of soil respiration coincided with the seasonal climate pattern, with high respiration rates in the hot humid season (April-September) and with low rates in the cool dry season (October-March). Soil respiration measured at these forests showed a clear increasing trend with the progressive succession. Annual mean (± SD) soil respiration rate in the DNR forests was (9.0±4.6) Mg CO2-C/hm2 per year, ranging from (6.1±3.2) Mg CO2-C/hm2 per year in early successional forests to (10.7±4.9) Mg CO2-C/hm2 per year in advanced successional forests. Soil respiration was correlated with both soil temperature and moisture. The T/M model, where the two biophysical variables are driving factors, accounted for 74%-82% of soil respiration variation in DNR forests. Temperature sensitivity decreased along progressive succession stages, suggesting that advanced-successional forests have a good ability to adjust to temperature. In contrast, moisture increased with progressive succession processes. This increase is caused, in part, by abundant respirators in advanced-successional forest, where more soil moisture is needed to maintain their activities.

  19. Dependence of soil respiration on soil temperature and soil moisture in successional forests in Southern China

    Science.gov (United States)

    Tang, X.-L.; Zhou, G.-Y.; Liu, S.-G.; Zhang, D.-Q.; Liu, S.-Z.; Li, Ji; Zhou, C.-Y.

    2006-01-01

    The spatial and temporal variations in soil respiration and its relationship with biophysical factors in forests near the Tropic of Cancer remain highly uncertain. To contribute towards an improvement of actual estimates, soil respiration rates, soil temperature, and soil moisture were measured in three successional subtropical forests at the Dinghushan Nature Reserve (DNR) in southern China from March 2003 to February 2005. The overall objective of the present study was to analyze the temporal variations of soil respiration and its biophysical dependence in these forests. The relationships between biophysical factors and soil respiration rates were compared in successional forests to test the hypothesis that these forests responded similarly to biophysical factors. The seasonality of soil respiration coincided with the seasonal climate pattern, with high respiration rates in the hot humid season (April-September) and with low rates in the cool dry season (October-March). Soil respiration measured at these forests showed a clear increasing trend with the progressive succession. Annual mean (±SD) soil respiration rate in the DNR forests was (9.0 ± 4.6) Mg CO2-C/hm2per year, ranging from (6.1 ± 3.2) Mg CO2-C/hm2per year in early successional forests to (10.7 ± 4.9) Mg CO2-C/hm2 per year in advanced successional forests. Soil respiration was correlated with both soil temperature and moisture. The T/M model, where the two biophysical variables are driving factors, accounted for 74%-82% of soil respiration variation in DNR forests. Temperature sensitivity decreased along progressive succession stages, suggesting that advanced-successional forests have a good ability to adjust to temperature. In contrast, moisture increased with progressive succession processes. This increase is caused, in part, by abundant respirators in advanced-successional forest, where more soil moisture is needed to maintain their activities.

  20. Relationships between soil erosion risk, soil use and soil properties in Mediterranean areas. A comparative study of three typical sceneries

    Science.gov (United States)

    Gil, Juan; Priego-Navas, Mercedes; Zavala, Lorena M.; Jordán, Antonio

    2013-04-01

    Generally, literature shows that the high variability of rainfall-induced soil erosion is related to climatic differences, relief, soil properties and land use. Very different runoff rates and soil loss values have been reported in Mediterranean cropped soils depending on soil management practices, but also in soils under natural vegetation types. OBJECTIVES The aim of this research is to study the relationships between soil erosion risk, soil use and soil properties in three typical Mediterranean areas from southern Spain: olive groves under conventional tillage, minimum tillage and no-till practices, and soils under natural vegetation. METHODS Rainfall simulation experiments have been carried out in order to assess the relationship between soil erosion risk, land use, soil management and soil properties in olive-cropped soils under different types of management and soils under natural vegetation type from Mediterranean areas in southern Spain RESULTS Results show that mean runoff rates decrease from 35% in olive grove soils under conventional tillage to 25% in olive (Olea europaea) grove soils with minimum tillage or no-till practices, and slightly over 22% in soils under natural vegetation. Moreover, considering the different vegetation types, runoff rates vary in a wide range, although runoff rates from soils under holm oak (Quercus rotundifolia), 25.70%, and marginal olive groves , 25.31%, are not significantly different. Results from soils under natural vegetation show that the properties and nature of the organic residues play a role in runoff characteristics, as runoff rates above 50% were observed in less than 10% of the rainfall simulations performed on soils with a organic layer. In contrast, more than half of runoff rates from bare soils reached or surpassed 50%. Quantitatively, average values for runoff water losses increase up to 2.5 times in unprotected soils. This is a key issue in the study area, where mean annual rainfall is above 600 mm