WorldWideScience

Sample records for surrounding bare soil

  1. Soil microbial activities beneath Stipa tenacissima L. and in surrounding bare soil

    Science.gov (United States)

    Novosadová, I.; Ruiz Sinoga, J. D.; Záhora, J.; Fišerová, H.

    2010-05-01

    Open steppes dominated by Stipa tenacissima L. constitute one of the most representative ecosystems of the semi-arid zones of Eastern Mediterranean Basin (Iberian Peninsula, North of Africa). These steppes show a higher degree of variability in composition and structure. Ecosystem functioning is strongly related to the spatial pattern of grass tussocks. Soils beneath S. tenacissima grass show higher fertility and improved microclimatic conditions, favouring the formation of "resource islands" (Maestre et al., 2007). On the other hand in "resource islands" and in surrounding bare soil exists the belowground zone of influence. The competition for water and resources between plants and microorganisms is strong and mediated trough an enormous variety of exudates and resource depletion intended to regulate soil microbial communities in the rhizosphere, control herbivory, encourage beneficial symbioses, and change chemical and physical properties in soil (Pugnaire et Armas, 2008). Secondary compounds and allelopathy restrict other species growth and contribute to patchy plant distribution. Active root segregation affects not only neighbourś growth but also soil microbial activities. The objective of this study was to assess the effect of Stipa tenacissima on the key soil microbial activities under controlled incubation conditions (basal and potential respiration; net nitrogen mineralization). The experimental plots were located in the province Almería in Sierra de los Filabres Mountains near the village Gérgal (southeast Spain) in the small catchment which is situated between 1090 - 1165 m a.s.l. The area with extent of 82 000 m2 is affected by soil degradation. The climate is semiarid Mediterranean. The mean annual rainfall is of about 240 mm mostly concentrated in autumn and spring. The mean annual temperature is 13.9° C. The studied soil has a loam to sandy clay texture and is classified as Lithosol (FAO-ISRIC and ISSS, 1998). The vegetation of these areas is an

  2. Effect of soil property on evaporation from bare soils

    Science.gov (United States)

    Zhang, Chenming; Li, Ling; Lockington, David

    2015-04-01

    Quantifying the actual evaporation rate from bare soils remains a challenging task as it not only associates with the atmospheric demand and liquid water saturation on the soil surface, but also the properties of the soils (e.g., porosity, pore size distribution). A physically based analytical model was developed to describe the surface resistance varying with the liquid water saturation near the soil surface. This model considers the soil pore size distribution, hydraulic connection between the main water cluster and capillary water in the soil surface when the soil surface is wet and the thickness of the dry soil layer when the soil surface is dry. The surface resistance model was then integrated to a numerical model based on water balance, heat balance and surface energy balance equations. The integrated model was validated by simulating water and heat transport processes during six soil column drying experiments. The analysis indicates that the when soil surface is wet, the consideration of pore size distribution in the surface resistance model offers better estimation of transient evaporation among different soil types than the estimations given by empirically based surface resistance models. Under fixed atmospheric boundary condition and liquid water saturation, fine sand has greater evaporation rate than coarse sand as stronger capillary force devlivers more water from the main water cluster. When the soil surface becomes dry, the impact of soil property to evaporation becomes trivial as the thickness of the dry soil layer turns to be the key factor to determine the evaporation rate.

  3. Evaporation Dynamics of Moss and Bare Soil in Boreal Forests

    Science.gov (United States)

    Dempster, S.; Young, J. M.; Barron, C. G.; Bolton, W. R.

    2013-12-01

    Evaporation dynamics of mosses is a critical process in boreal and arctic systems and represents a key uncertainty in hydrology and climate models. At this point, moss evaporation is not well quantified at the plot or landscape scale. Relative to bare soil or litter evaporation, moss evaporation can be challenging to predict because the water flux is not isolated to the moss surface. Evaporation can originate from nearly 10 cm below the surface. Some mosses can wick moisture from even deeper than 10 cm, which subsequently evaporates. The goal of this study was to use field measurements to quantify the moss evaporation dynamics in a coniferous forest relative to bare ground or litter evaporation dynamics in a deciduous forest in Interior Alaska. Measurements were made in two ecosystem types within the boreal forest of Interior Alaska: a deciduous forest devoid of moss and a coniferous forest with a thick moss layer. A small clear chamber was attached to a LiCor 840 infrared gas analyzer in a closed loop system with a low flow rate. Water fluxes were measured for ~ 90 seconds on each plot in dry and wet soil and moss conditions. Additional measurements included: soil temperature, soil moisture, air temperature, barometric pressure, dew point, relative humidity, and wind speed. Thermal infrared images were also captured in congruence with water flux measurements to determine skin temperature. We found that the moss evaporation rate was over 100% greater than the soil evaporation rate (0.057 g/min vs. 0.024 g/min), and evaporation rates in both systems were most strongly driven by relative humidity and surface temperature. Surface temperature was lower at the birch site than the black spruce site because trees shade the surface beneath the birch. High fluxes associated with high water content were sustained for a longer period of time over the mosses compared to the bare soil. The thermal IR data showed that skin temperature lagged the evaporation flux, such that the

  4. Karst bare slope soil erosion and soil quality: a simulation case study

    Directory of Open Access Journals (Sweden)

    Q. Dai

    2015-06-01

    Full Text Available The influence on soil erosion by different bedrock bareness ratios, different rainfall intensities, different underground pore fissure degrees and rainfall duration are researched through manual simulation of microrelief characteristics of karst bare slopes and underground karst crack construction in combination with artificial simulation of rainfall experiment. The results show that firstly, when the rainfall intensity is small (30 and 50 mm h−1, no bottom load loss is produced on the surface, and surface and underground runoff and sediment production is increased with the increasing of rainfall intensity; secondly, surface runoff and sediment production reduced with increased underground pore fissure degree, while underground runoff and sediment production increased; thirdly, raindrops hit the surface, forming a crust with rainfall duration. The formation of crusts increases surface runoff erosion and reduces soil infiltration rate. Increasing of surface runoff erosion damaged crust and increased soil seepage rate. Raindrops continued to hit the surface, leading the formation of crust. Soil permeability showed volatility which were from reduction to increases and reduction, and so on. Surface and subsurface runoff were volatility with rainfall duration; fourthly, when rock bareness ratio is 50% and rainfall intensities are 30 and 50 mm h−1, runoff is not produced on the surface, and the slope runoff and sediment production presents a fluctuating change with increased rock bareness ratio; fifthly, the correlation degree between the slope runoff and sediment production and all factors are as follows: rainfall intensity > rainfall duration > underground pore fissure degree > bed rock bareness ratio.

  5. Soil water repellency under stones, forest residue mulch and bare soil following wildfire.

    Science.gov (United States)

    Martins, Martinho A. S.; Prats, Sérgio A.; van Keulen, Daan; Vieira, Diana C. S.; Silva, Flávio C.; Keizer, Jan J.; Verheijen, Frank G. A.

    2017-04-01

    Soil water repellency (SWR) is a physical property that is commonly defined as the aptitude of soil to resist wetting. It has been documented for a wide range of soil and vegetation types, and can vary with soil organic matter (SOM) content and type, soil texture, soil moisture content (SMC) and soil temperature. Fire can induce, enhance or destroy SWR and, therefore, lead to considerable changes in soil water infiltration and storage and increase soil erosion by water, thereby weakening soil quality. In Portugal, wildfires occur frequently and affect large areas, on average some 100000 ha per year, but over 300000 ha in extreme years such as 2003 and 2005. This can have important implications in geomorphological and hydrological processes, as evidenced by the strong and sometimes extreme responses in post-fire runoff and erosion reported from various parts of the world, including Portugal. Thereby, the application of mulches from various materials to cover burned areas has been found to be an efficient stabilization treatment. However, little is known about possible side effects on SWR, especially long term effects. Forest SWR is very heterogeneous, as a result of variation in proximity to trees/shrubs, litter type and thickness, cracks, roots, and stones. This study targeted the spatial heterogeneity of soil water repellency under eucalypt plantation, five years after a wildfire and forest residue mulching application. The main objectives of this work were: 1) to assess the long-term effect of mulching application on the strength and spatial heterogeneity of topsoil SWR, by comparing SWR on bare soil, under stones, and under mulching remains; 2) to assess SWR at 1 cm depth between O and Ah horizons. The soil surface results showed that untreated bare soil areas were slightly more water repellent than mulched areas. However, under stones there were no SWR differences between mulched and control areas. At 1 cm depth, there was a marked mulching effect on SWR, even

  6. PRELIMINARY RESULTS OF ESTIMATING SOIL MOISTURE OVER BARE SOIL USING FULL-POLARIMETRIC ALOS-2 DATA

    Directory of Open Access Journals (Sweden)

    A. Sekertekin

    2016-10-01

    Full Text Available Synthetic Aperture Radar (SAR imaging system is one of the most effective way for Earth observation. The aim of this study is to present the preliminary results about estimating soil moisture using L-band Synthetic Aperture Radar (SAR data. Full-polarimetric (HH, HV, VV, VH ALOS-2 data, acquired on 22.04.2016 with the incidence angle of 30.4o, were used in the study. Simultaneously with the SAR acquisition, in-situ soil moisture samples over bare agricultural lands were collected and evaluated using gravimetric method. Backscattering coefficients for all polarizations were obtained and linear regression analysis was carried out with in situ moisture measurements. The best correlation coefficient was observed with VV polarization. Cross-polarized backscattering coefficients were not so sensitive to soil moisture content. In the study, it was observed that soil moisture maps can be retrieved with the accuracy about 14% (RMSE.

  7. Quantifying and isolating stable soil organic carbon using long-term bare fallow experiment

    DEFF Research Database (Denmark)

    Barré, P; Eglin, T; Christensen, Bent Tolstrup;

    2010-01-01

    The stability of soil organic matter (SOM) is a major source of uncertainty in predicting atmospheric CO2 concentration during the 21st century. Isolating the stable soil carbon (C) from other, more labile, C fractions in soil is of prime importance for calibrating soil C simulation models......, and gaining insights into the mechanisms that lead to soil C stability. Long-term experiments with continuous bare fallow (vegetation-free) treatments in which the decay of soil C is monitored for decades after all inputs of C have stopped, provide a unique opportunity to assess the quantity of stable soil C....... We analyzed data from six bare fallow experiments of long-duration (>30 yrs), covering a range of soil types and climate conditions, and sited at Askov (Denmark), Grignon and Versailles (France), Kursk (Russia), Rothamsted (UK), and Ultuna (Sweden). A conceptual three pool model dividing soil C...

  8. Implications of climate change for evaporation from bare soils in a Mediterranean environment.

    Science.gov (United States)

    Aydin, Mehmet; Yano, Tomohisa; Evrendilek, Fatih; Uygur, Veli

    2008-05-01

    The purpose of this study was to predict quantitative changes in evaporation from bare soils in the Mediterranean climate region of Turkey in response to the projections of a regional climate model developed in Japan (hereafter RCM). Daily RCM data for the estimation of reference evapotranspiration (ETr) and soil evaporation were obtained for the periods of 1994--2003 and 2070--2079. Potential evaporation (Ep) from bare soils was calculated using the Penman-Monteith equation with a surface resistance of zero. Simulation of actual soil evaporation (Ea) was carried out using Aydin model (Aydin et al., Ecological Modelling 182:91-105, 2005) combined with Aydin and Uygur (2006, A model for estimating soil water potential of bare fields. In Proceedings of the 18th International Soil Meeting (ISM) on Soils Sustaining Life on Earth, Managing Soil and Technology, Sanliurfa, 477-480pp.) model of predicting soil water potential at the top surface layer of a bare soil, after performances of Aydin model (R2 = 94.0%) and Aydin and Uygur model (R2 = 97.6) were tested. The latter model is based on the relations among potential soil evaporation, hydraulic diffusivity, and soil wetness, with some simplified assumptions. Input parameters of the model are simple and easily obtainable such as climatic parameters used to compute the potential soil evaporation, average diffusivity for the drying soil, and volumetric water content at field capacity. The combination of Aydin and Aydin and Uygur models appeared to be useful in estimating water potential of soils and Ea from bare soils, with only a few parameters. Unlike ETr and Ep projected to increase by 92 and 69 mm (equivalent to 8.0 and 7.3% increases) due to the elevated evaporative demand of the atmosphere, respectively, Ea from bare soils is projected to reduce by 50 mm (equivalent to a 16.5% decrease) in response to a decrease in rainfall by 46% in the Mediterranean region of Turkey by the 2070s predicted by RCM, and consequently

  9. Inversion of dielectric constant and moisture of bare soil surface from backscattering coefficient

    Institute of Scientific and Technical Information of China (English)

    李宗谦; 冯孔豫

    1997-01-01

    An inverse method of dielectric constant and moisture of bare wet soil surface from backscattering coefficients is presented, which is based upon the small perturbation model of electromagnetic wave scattering from rough surfaces and the empirical and dielectric mixing models of wet soil. Some sets of curves which describe the relation between the moisture of soil and the ratio of like polarization backscattering coefficients σvv and σhh are obtained, and some principles on how to choose the incident frequencies and the incident angles of the electromagnetic wave are given Analysis and calculation show that the mam advantage of this inverse method is its efficiency and simplicity.

  10. The contribution of vegetation cover and bare soil to pixel reflectance in an arid ecosystem

    Science.gov (United States)

    Steele, C. M.; Smith, A.; Campanella, A.; Rango, A.

    2008-12-01

    The heterogeneity of vegetation and soils in arid and semi-arid environments complicates the analysis of medium spatial resolution remotely sensed imagery. A single pixel may contain several different types of vegetation, as well as a sizeable proportion of bare soil. We have used linear mixture modeling to explore the contribution of vegetation cover and bare soil to pixel reflectance. In October, 2006, aerial imagery (0.25 m spatial resolution) was acquired for our study sites in the Jornada Experimental Range, southern New Mexico. Imagery was also acquired from the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) for June and November, 2006. These data corresponded with pre- and post monsoon conditions. Object-based feature extraction was used to classify the aerial imagery to shrub, grass and bare ground cover classes. Percent cover was then calculated for each cover class. Visible-near-infrared and shortwave infrared ASTER reflectance data from both dates were combined into a single 18-band dataset (30 m spatial resolution). A vector overlay from the classification results of the aerial imagery was used to define pure endmember pixels in the ASTER imagery. Estimates of the proportions of shrub, grass and bare ground cover from the linear mixture modeling approach were compared with cover calculated using feature extraction from the aerial imagery. The results indicate that reflectance in ASTER pixels is likely to be a linear combination of the cover proportions of the three main cover types (shrubs, grass, bare ground). However, noticeable outliers in the relationship between cover calculated from each method, indicate there may be other variables that affect the accuracy with which we can estimate cover using linear mixture modeling.

  11. Mutual seismic interaction between tunnels and the surrounding granular soil

    Directory of Open Access Journals (Sweden)

    Mohamed Ahmed Abdel-Motaal

    2014-12-01

    Study results show that the maximum exerted straining actions in tunnel lining are directly proportional to the relative stiffness between tunnel and surrounding soil (lining thickness and soil shear modulus. Moreover, it is highly affected by the peak ground acceleration and the tunnel location (embedment depth. A comprehensive study is performed to show the effect of tunnel thickness and tunnel diameter on both the induced bending moment and lining deformation. In general, it is concluded that seismic analysis should be considered in regions subjected to peak ground acceleration greater than 0.15g.

  12. Towards new methodology for improvement of topographic and anisotropic correction of desert bare soil

    Science.gov (United States)

    Alomran, Ali

    Desert bare soil has been found in literature to exhibit anisotropic reflectance behaviour. Anisotropy is described by Bidirectional Reflectance Distribution function (BRDF). Literature studies have limited their investigations to the behaviour of the topographic corrections of Minnaert and C models (simple forms of the empirical type of BRDF) with terrain variables (slope and orientation). Yet, none of these studies, especially for desert bare soil, has investigated the behaviour of the coefficient values of Minnaert and C with terrain variables. The investigation in this study has revealed that the relation between terrain slope (derived from both DEM level-1 and level-2) of desert bare soil in Saudi Arabia and K and C values follow closely a 2nd order polynomial trend. K curves have taken convex shapes, whereas C curves were concave. The Minnaert (K) and C coefficients trends have shown that surface Lambertian behaviour is more pronounced on slopes facing away from the sun than on sun facing slopes. Unlike the Minnaert K and C coefficients derived from four spectral classes, this author's newly developed terrain slope, aspect and phase angle dependant's C and Minnaert coefficients produced promising results compared to the global K and C. Induced BRDF effects in the desert bare soil is found the more probable dominating cause for the scatter/jitter in the radiance/cos(i) regression plots that remained after radiometric correction. Though its high topographic correction efficiency and unlike Minnaert model, C model tends to maintain the uncorrected radiance values unchanged after correction (i.e. not amplified to compensate for low sun angle).

  13. A Simulating Experiment in the Process of Soil Erosion on Bare Land in Mt. Tanakami

    Institute of Scientific and Technical Information of China (English)

    ZHAO Wei; HU Ke; WANG Xikui; Akitsu KIMOTO; Takahisa MIZUYAMA

    2001-01-01

    In order to understand the process of surface erosion and acquire basic data of conditions on hillslope without vege tation, a sprinkling experiment is conducted on a bare slope in Mt. Tanakami in the central part of Japan. Based on the mea surements of runoff, mean soil erosion depth, and sediment yield, etc. , the results suggest the following characteristics in the process of surface erosion in the experimental area. (1) The occurrence of sediment discharge is interrupted; (2) Surface runoff is a saturated overland flow; (3) The mean soil erosion depth is thick compared with other areas in Mt. Tanakami;(4) Sediment discharge process is detachment- limited.

  14. Comparison of different methods of image analysis for quantifying bare soil in rangelands

    Science.gov (United States)

    Pulido Fernández, M.; Lavado Contador, J. F.; Schnabel, S.; Gómez Gutiérrez, Á.

    2009-04-01

    Many authors emphasize the importance of vegetation in maintaining low levels of soil loss by means of its positive influence in reducing erosion. In some low-vegetated Mediterranean rangelands, especially those with high livestock densities, water erosion can ultimately lead to a partial or total loss of soils, particularly at the beginning of the rainy season, when the surface cover is reduced after the dry summer period. In relation with this, it is essential to develop accurate methods allowing the quantification of bare soil which, in turn, can inform about the influence of different livestock management alternatives over the land system. The main goal of this work is the comparison of the ability of various pixel-based as well as object-oriented methods of image classification for the quantification of bare soil at a fine spatial resolution. The study area is a farm located in a woody rangeland (dehesa) in SW Spain covering a surface area of 1,024 hectare. A three bands (RGB) orthophoto image with a pixel size of 0,4 metres was used, together with its brightness component, to compare the classification of bare soil vs covered soil by means of the following methods: unsupervised classification (k-means algorithm), supervised classification (maximum likelihood classification, minimum distance or nearest neighbour and Mahalanobis distance) and object oriented classification through a multiresolution segmentation. The results of classification were tested using 700 to 1000 points of field validation. Different combinations of image layers as well as validation algorithms were applied to assess for the better classification results. The best unsupervised classification was obtained from a combination of the RGB layers with the brightness component of the image. A total of 93.1 % of the field data were correctly classified and the Area Under the Curve (AUC) obtained with the ROC (Receiving Operating Characteristic) validation technique amounted to 0.91. With this

  15. Inversion of Electromagnetic Models for Bare Soil Parameter Estimation from Multifrequency Polarimetric SAR Data

    Directory of Open Access Journals (Sweden)

    Nazzareno Pierdicca

    2008-12-01

    Full Text Available The potentiality of polarimetric SAR data for the estimation of bare soil geophysical parameters (i.e., roughness and soil moisture is investigated in this work. For this purpose, two forward models available in the literature, able to simulate the measurements of a multifrequency radar polarimeter, have been implemented for use within an inversion scheme. A multiplicative noise has been considered in the multidimensional space of the elements of the polarimetric Covariance Matrix, by adopting a complex Wishart distribution to account for speckle effects. An additive error has been also introduced on the simulated measurements to account for calibration and model errors. Maximum a Posteriori Probability and Minimum Variance criteria have been considered to perform the inversion. As for the algorithms to implement the criteria, simple optimization/integration procedures have been used. A Neural Network approach has been adopted as well. A correlation between the roughness parameters has been also supposed in the simulation as a priori information, to evaluate its effect on the estimation accuracy. The methods have been tested on simulated data to compare their performances as function of number of looks, incidence angles and frequency bands, thus identifying the best radar configuration in terms of estimation accuracy. Polarimetric measurements acquired during MAC Europe and SIR-C campaigns, over selected bare soil fields, have been also used as validation data.

  16. Benefits and limitations of pig slurry to reclaim bare mine soils under Mediterranean semiarid conditions

    Science.gov (United States)

    Zornoza, Raúl; Faz, Ángel; Acosta, Jose A.; Kabas, Sebla; Martínez-Martínez, Silvia; Ángeles Muñoz, M.

    2013-04-01

    In this study, the effects of pig slurry application on reclamation of mine soils from Cartagena-La Unión Mining District (SE Spain) were investigated in a field experiment. Exchangeable metals (Cd, Cu, Pb and Zn), total organic carbon, total nitrogen, soluble carbon, microbial biomass and three enzyme activities were periodically monitored during 67 days. In addition, one year after the application of the pig slurry, soil and developed vegetation was sampled. Results showed that only exchangeable Cd and Zn significantly decreased in the amended plots, mainly for Cd, with decreases of 98%. The rest of metals and chemical properties did not change with time after application of amendments, showing values not significantly different than those present before pig slurry application. Soluble carbon, microbial biomass carbon and the enzyme activities increased after the application of pig slurry. However, after various days these parameters started a decreasing trend until reaching values similar to the control from approximately day 25. Thus, mainly precipitation as phosphate from the waste was very effective for Cd immobilization. No increments were observed in soil organic carbon because the organic carbon applied with the slurry was too low to be significantly detected. Nonetheless, pig slurry is a good fertilizer owing to the high quantity of nutrients provided, needed to promote the development of vegetation. One year after application, a native vegetation cover (25-30%) was reached by spontaneous colonization. Triggered plant growth by the effect of amendment improved soil conditions, particularly by the help of the medium created by their rhizosphere systems. Increments in soil organic carbon and total nitrogen, and decreases in the exchangeable metals fraction concentration were observed in rhizospheric soils when compared to the bare soils. This improvement in soil quality mediated by vegetation was more efficient than the direct effect of the amendment. In

  17. Measurements, interpretation and climate change effects evaluation for pyroclastic bare soil evaporation

    Science.gov (United States)

    Rianna, G.; Pagano, L.; Mercogliano, P.; Montesarchio, M.

    2012-12-01

    A physical model has been designed to achieve the following goals: to mark out the main features of the soil-atmosphere interaction; to quantify the water and energy fluxes through the soil surface during several years; to monitor the trends of the main variables regulating the hydraulic and thermal conditions. It is constituted by a soil volume (about 1mc) exposed to weather forcing; it is instrumented at four depths by sensors for measuring suction, water content and temperature. Therefore, a station allows knowing the meteo variables (rainfall, wind velocity and direction, air temperature, air pressure and relative humidity) and the two directly measurable components of the energy balance at the soil surface (net radiation and soil heat flux). Under the soil specimen, three shear beam load cells measure the soil weight and, hence, because the soil particles weight can be assumed as constant, the sample water storage. As first attempt, the soil surface is kept bare to avoid the complications led by overlapping processes induced by vegetation (interception, transpiration). Since May 2010, the soil involved in testing is pyroclastic material (silty sand) representative of air fall deposits covering a large part of Campania (South Italy) and erupted in the last 10,000 years by different volcanic centres (Phlegrean fields, Vesuvius). Because of their genesis, these soils show peculiar features: high porosity, low weight of soil unit volume, high water retention capacity; they cause an unusual hydraulic behaviour, halfway between coarse and fine soils in terms of saturated hydraulic permeability and mean slope of soil-water characteristic curve. In turn, these elements induce, among other things, that the currently adopted predictive approaches to estimate, for example, infiltration and evaporation processes are not directly suitable for these soils as the available parameters, even for grain sizes comparable to those of pyroclastic soils, fail to reproduce the

  18. A New Empirical Model for Radar Scattering from Bare Soil Surfaces

    Directory of Open Access Journals (Sweden)

    Nicolas Baghdadi

    2016-11-01

    Full Text Available The objective of this paper is to propose a new semi-empirical radar backscattering model for bare soil surfaces based on the Dubois model. A wide dataset of backscattering coefficients extracted from synthetic aperture radar (SAR images and in situ soil surface parameter measurements (moisture content and roughness is used. The retrieval of soil parameters from SAR images remains challenging because the available backscattering models have limited performances. Existing models, physical, semi-empirical, or empirical, do not allow for a reliable estimate of soil surface geophysical parameters for all surface conditions. The proposed model, developed in HH, HV, and VV polarizations, uses a formulation of radar signals based on physical principles that are validated in numerous studies. Never before has a backscattering model been built and validated on such an important dataset as the one proposed in this study. It contains a wide range of incidence angles (18°–57° and radar wavelengths (L, C, X, well distributed, geographically, for regions with different climate conditions (humid, semi-arid, and arid sites, and involving many SAR sensors. The results show that the new model shows a very good performance for different radar wavelengths (L, C, X, incidence angles, and polarizations (RMSE of about 2 dB. This model is easy to invert and could provide a way to improve the retrieval of soil parameters.

  19. Effect of deep injection on field-scale emissions of 1,3-dichloropropene and chloropicrin from bare soil

    Science.gov (United States)

    Yates, S. R.; Ashworth, D. J.; Zheng, W.; Knuteson, J.; van Wesenbeeck, I. J.

    2016-07-01

    Fumigating soil is important for the production of many high-value vegetable, fruit, and tree crops, but fumigants are toxic pesticides with relatively high volatility, which can lead to significant atmospheric emissions. A field experiment was conducted to measure emissions and subsurface diffusion of a mixture of 1,3-dichloropropene (1,3-D) and chloropicrin after shank injection to bare soil at 61 cm depth (i.e., deep injection). Three on-field methods, the aerodynamic (ADM), integrated horizontal flux (IHF), and theoretical profile shape (TPS) methods, were used to obtain fumigant flux density and cumulative emission values. Two air dispersion models (CALPUFF and ISCST3) were also used to back-calculate the flux density using air concentration measurements surrounding the fumigated field. Emissions were continuously measured for 16 days and the daily peak emission rates for the five methods ranged from 13 to 33 μg m-2 s-1 for 1,3-D and 0.22-3.2 μg m-2 s-1 for chloropicrin. Total 1,3-D mass lost to the atmosphere was approximately 23-41 kg ha-1, or 15-27% of the applied active ingredient and total mass loss of chloropicrin was <2%. Based on the five methods, deep injection reduced total emissions by approximately 2-24% compared to standard fumigation practices where fumigant injection is at 46 cm depth. Given the relatively wide range in emission-reduction percentages, a fumigant diffusion model was used to predict the percentage reduction in emissions by injecting at 61 cm, which yielded a 21% reduction in emissions. Significant reductions in emissions of 1,3-D and chloropicrin are possible by injecting soil fumigants deeper in soil.

  20. A hydrometeorological approach for probabilistic simulation of monthly soil moisture under bare and crop land conditions

    Science.gov (United States)

    Das, Sarit Kumar; Maity, Rajib

    2015-04-01

    This study focuses on the probabilistic estimation of monthly soil moisture variation by considering (a) the influence of hydrometeorological forcing to model the temporal variation and (b) the information of Hydrological Soil Groups (HSGs) and Agro-Climatic Zones (ACZs) to capture the spatial variation. The innovative contributions of this study are: (i) development of a Combined Hydro-Meteorological (CHM) index to extract the information of different influencing hydrometeorological variables, (ii) consideration of soil-hydrologic characteristics (through HSGs) and climate regime-based zoning for agriculture (through ACZs), and (iii) quantification of uncertainty range of the estimated soil moisture. Usage of Supervised Principal Component Analysis (SPCA) in the development of the CHM index helps to eliminate the "curse of dimensionality," typically arises in the multivariate analysis. The usage of SPCA also ensures the maximum possible association between the developed CHM index and soil moisture variation. The association between these variables is modeled through their joint distribution which is obtained by using the theory of copula. The proposed approach is also spatially transferable, since the information on HSGs and ACZs is considered. The "leave-one-out" cross-validation (LOO-CV) approach is adopted for stations belong to a particular HSG to examine the spatial transferability. The simulated soil moisture values are also compared with a few existing soil moisture data sets, derived from different Land Surface Models (LSMs) or retrieved from different satellite-based missions. The potential of the proposed approach is found to be promising and even applicable to crop land also, though with a lesser degree of efficiency as compared to bare land conditions.

  1. Soil particle tracing using RFID tags for elucidating the behavior of radiocesium on bare soil surfaces in Fukushima

    Science.gov (United States)

    Manome, Ryo; Onda, Yuichi; Patin, Jeremy; Stefani, Chiara; Yoshimura, Kazuya; Parsons, Tony; Cooper, James

    2014-05-01

    Radioactive materials are generally associated with soil particles in terrestrial environment and therefore the better understanding soil erosion processes is expected to improve the mitigation of radioactive risks. Spatial variability in soil erosion has been one of critical issues for soil erosion management. This study attempts to track soil particle movement on soil surfaces by employing Radio Frequency Identification (RFID) tags for the better understanding radiocesium behavior. A RFID tag contains a specific electronically identifier and it permits tracing its movement by reading the identifier. In this study, we made artificial soil particles by coating the RFID tags with cement material. The particle diameters of the artificial soil particles approximately ranged from 3 to 5 mm. The artificial soil particles were distributed in a reticular pattern on a soil erosion plot (bare soil surface, 22.13 m length × 5 m width, 4.4° slope) in Kawamata town where radiocesium deposited because of the Fukushima Dai-ichi power plant accident. After their distribution on October 2012, we had read the identifiers of RFID tags and recorded their locations on the plot for 14 times by September 2013. Moving distance (MD) was calculated based on the difference of the location for each sampling date. The topographical changes on the plot were also monitored with a laser scanner to describe interrill erosion and rill erosion area on 11occasions. Median MD is 10.8cm for all the observations. Median MD on interrill and rill erosion areas were 9.8 cm and 20.7 cm, respectively. Seasonal variation in MD was observed; an extremely large MD was found in May 2013, at the first reading after the winter season. This large MD after winter suggests that snowmelt runoff was the dominant process which transported the soil particles. Comparing the MD with the observed amounts of rainfall, sediment and runoff on the plot, significant positive correlation were found if the data of May, 2013

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

    Science.gov (United States)

    Boroomand, Naser; Maleki, Mohammad Reza

    2010-05-01

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

  3. Cross-satellite comparison of operational land surface temperature products derived from MODIS and ASTER data over bare soil surfaces

    Science.gov (United States)

    Duan, Si-Bo; Li, Zhao-Liang; Cheng, Jie; Leng, Pei

    2017-04-01

    The collection 6 (C6) MODIS land surface temperature (LST) product is publicly available for the user community. Compared to the collection 5 (C5) MODIS LST product, the C6 MODIS LST product has been refined over bare soil pixels. Assessing the accuracy of the C6 MODIS LST product will help to facilitate the use of the LST product in various applications. In this study, we present a cross-satellite comparison to evaluate the accuracy of the C6 MODIS LST product (MOD11_L2) over bare soil surfaces under various atmospheric and surface conditions using the ASTER LST product as a reference. For comparison, the C5 MODIS LST product was also used in the analysis. The absolute biases (0.2-1.5 K) of the differences between the C6 MODIS LST and ASTER LST over bare soil surfaces are approximately two times less than those (0.6-3.8 K) of the differences between the C5 MODIS LST and ASTER LST. Furthermore, the RMSEs (0.7-2.3 K) over bare soil surfaces for the C6 MODIS LST are significantly smaller than those (0.9-4.2 K) for the C5 MODIS LST. These results indicate that the accuracy of the C6 MODIS LST product is much better than that of the C5 MODIS LST product. We recommend that the user community employs the C6 MODIS LST product in their applications.

  4. Carbonyl sulfide and dimethyl sulfide fluxes in an urban lawn and adjacent bare soil in Guangzhou, China.

    Science.gov (United States)

    Yi, Zhigang; Wang, Xinming

    2011-01-01

    Carbonyl sulfide (COS) and dimethyl sulfide (DMS) fluxes from an urban Cynodon dactylon lawn and adjacent bare soil were measured during April-July 2005 in Guangzhou, China. Both the lawn and bare soil acted as sinks for COS and sources for DMS. The mean fluxes of COS and DMS in the lawn (-19.27 and 18.16 pmol/(m2 sec), respectively) were significantly higher than those in the bare soil (-9.89 and 9.35 pmol/(m2 sec), respectively). Fluxes of COS and DMS in mowed lawn were also higher than those in bare soils. Both COS and DMS fluxes showed diurnal variation with detectable but much lower values in the nighttime than in the daytime. COS fluxes were related significantly to temperature and the optimal temperature for COS uptake was 29 degrees C. While positive linear correlations were found between DMS fluxes and temperature. COS fluxes increased linearly with ambient COS mixing ratios, and had a compensation point of 336 ppt.

  5. Carbonyl sulfide and dimethyl sulfide fluxes in an urban lawn and adjacent bare soil in Guangzhou, China

    Institute of Scientific and Technical Information of China (English)

    Zhigang Yi; Xinming Wang

    2011-01-01

    Carbonyl sulfide (COS) and dimethyl sulfide (DMS) fluxes from an urban Cynodon dactylon lawn and adjacent bare soil were measured during April-July 2005 in Guangzhou, China.Both the lawn and bare soil acted as sinks for COS and sources for DMS.The mean fluxes of COS and DMS in the lawn (-19.27 and 18.16 pmol/(m2·sec), respectively) were significantly higher than those in the bare soil (-9.89 and 9.35 pmol/(m2·sec), respectively).Fluxes of COS and DMS in mowed lawn were also higher than those in bare soils.Both COS and DMS fluxes showed diurnal variation with detectable but much lower values in the nighttime than in the daytime.COS fluxes were related significantly to temperature and the optimal temperature for COS uptake was 29℃.While positive linear correlations were found between DMS fluxes and temperature.COS fluxes increased linearly with ambient COS mixing ratios,and had a compensation point of 336 ppt.

  6. Marble waste and pig manure amendments decrease metal availability, increase soil quality and facilitate vegetation development in bare mine soils

    Science.gov (United States)

    Zornoza, Raúl; Faz, Ángel; Martínez-Martínez, Silvia; Acosta, José A.; Gómez, M. Dolores; Ángeles Muñoz, M.

    2013-04-01

    In order to bring out a functional and sustainable land use in a highly contaminated mine tailing, firstly environmental risks have to be reduced or eliminated by suitable reclamation activities. Tailing ponds pose environmental hazards, such as acidity and toxic metals reaching to waters through wind and water erosions and leaching. As a consequence, soils have no vegetation and low soil organic matter and nutrients. Various physicochemical and biochemical properties, together with exchangeable metals were measured before, 6 months and 12 months after the application of marble waste and pigs manure as reclamation strategy in a tailing pond from SE Spain to reduce hazards for environment and human health. Three months after the last addition of amendments, eight different native shrub species where planted for phytostabilization. Results showed the pH increased up to neutrality. Aggregates stability, organic carbon, total nitrogen, cation exchange capacity, bioavailable phosphorus and potassium, microbial biomass and microbial activity increased with the application of the amendments, while exchangeable metals drastically decreased (~90%). After one year of plantation, only 20% planted species died, with a high growth of survivals reaching flowering and fructification. This study confirms the high effectiveness of initial applications of marble wastes together with pig manure and plantation of shrub species to initialize the recovery of the ecosystem in bare mine soils under Mediterranean semiarid conditions. Key Words: pig manure, marble waste, heavy metals, mine soil. Acknowledgements This work has been funded by the European Union LIFE+ project MIPOLARE (LIFE09 ENV/ES/000439). J.A. Acosta acknowledges a "Saavedra Fajardo" contract from Comunidad Autónoma de Murcia (Spain)

  7. [Observations of spectral data and characteristics analysis of snow-bare soil mixed pixel generated by micro-simulation].

    Science.gov (United States)

    Liu, Yan; Li, Yang

    2014-07-01

    To explore the differences of mixed-pixel in spectral mixing mechanism at micro-and macro -scale, the micro- simulation of snow-bare soil mixed pixel was taken as the object of study in an artificial test environment. Reflectance spectra of mixed pixel and snow, bare soil endmember with different area ratio were collected by full-band spectrometer with fixed probe distance. Qualitative and quantitative analysis of original reflectance spectra was done, and reflectance spectra form 350 to 2 500 nm and normalized reflectance spectral data of 350 to 1 815 nm excluding noise were normalized. At the same time, we collected EOS/MODIS and Environment and Disaster Monitoring Satellites data of the same period over the same area and analyzed the correlation of channels in visible, near-infrared and shortwave infrared wavelength range at different resolution scales and the relationship between spectrum of mixed snow-soil and endmember pixel in MODIS image was analyzed. The results showed that, (1) At the micro scale, non-linear relationship existed between mixed pixel and endmember within the scope of the full-wave and linear relationship existed in sub-band wavelength range; (2) At the macro scale, linear relationship existed between mixed pixel and endmember. (3) In statistics of spectral values, the correlation between snow-soil mixture and endmember is positive for snow-soil mixture and snow endmember, and is negative for snow-soil mixture and soil endmember.

  8. Comparison of diurnal dynamics in evaporation rate between bare soil and moss-crusted soil within a revegetated desert ecosystem of northwestern China

    Indian Academy of Sciences (India)

    Ya-Feng Zhang; Xin-Ping Wang; Yan-Xia Pan; Rui Hu

    2016-02-01

    Effects of biological soil crusts (BSCs) on soil evaporation is quite controversial in literature, being either facilitative or inhibitive, and therein few studies have actually conducted direct evaporation measurements. Continuous field measurements of soil water evaporation were conducted on two microlysimeters, i.e., one with sand soil collected from bare sand dune area and the other with moss-crusted soil collected from an area that was revegetated in 1956, from field capacity to dry, at the southeastern edge of the Tengger Desert. We mainly aimed to quantify the diurnal variations of evaporation rate from two soils, and further comparatively discuss the effects of BSCs on soil evaporation after revegetation. Results showed that in clear days with high soil water content (Day 1 and 2), the diurnal variation of soil evaporation rate followed the typical convex upward parabolic curve, reaching its peak around midday. Diurnal evaporation rate and the accumulated evaporation amount of moss-crusted soil were lower (an average of 0.90 times) than that of sand soil in this stage. However, as soil water content decreased to a moderately low level (Day 3 and 4), the diurnal evaporation rate from moss-crusted soil was pronouncedly higher (an average of 3.91 times) than that of sand soil, prolonging the duration of this higher evaporation rate stage; it was slightly higher in the final stage (Day 5 and 6) when soil moisture was very low. We conclude that the effects of moss crusts on soil evaporation vary with different evaporation stages, which is closely related to soil water content, and the variation and transition of evaporation rate between bare soil and moss-crusted soil are expected to be predicted by soil water content.

  9. Estimation of ground heat flux from soil temperature over a bare soil

    Science.gov (United States)

    An, Kedong; Wang, Wenke; Wang, Zhoufeng; Zhao, Yaqian; Yang, Zeyuan; Chen, Li; Zhang, Zaiyong; Duan, Lei

    2017-08-01

    Ground soil heat flux, G 0, is a difficult-to-measure but important component of the surface energy budget. Over the past years, many methods were proposed to estimate G 0; however, the application of these methods was seldom validated and assessed under different weather conditions. In this study, three popular models (force-restore, conduction-convection, and harmonic) and one widely used method (plate calorimetric), which had well performance in publications, were investigated using field data to estimate daily G 0 on clear, cloudy, and rainy days, while the gradient calorimetric method was regarded as the reference for assessing the accuracy. The results showed that harmonic model was well reproducing the G 0 curve for clear days, but it yielded large errors on cloudy and rainy days. The force-restore model worked well only under rainfall condition, but it was poor to estimate G 0 under rain-free conditions. On the contrary, the conduction-convection model was acceptable to determine G 0 under rain-free conditions, but it generated large errors on rainfall days. More importantly, the plate calorimetric method was the best to estimate G 0 under different weather conditions compared with the three models, but the performance of this method is affected by the placement depth of the heat flux plate. As a result, the heat flux plate was recommended to be buried as close as possible to the surface under clear condition. But under cloudy and rainy conditions, the plate placed at depth of around 0.075 m yielded G 0 well. Overall, the findings of this paper provide guidelines to acquire more accurate estimation of G 0 under different weather conditions, which could improve the surface energy balance in field.

  10. Impact of mine tailings on surrounding soils: Case

    African Journals Online (AJOL)

    H. ABDURAHMAN

    Article Number: AD77AF156458. ISSN 1996-0786 ... Key words: Contamination, heavy metals, soils, mine area, mine tailings, Marrakech – Morocco. INTRODUCTION ... thallium, and iron are transported to the environment (Lee and Kao, 2004 ...

  11. Assessing Fractional Tree, Grass, and Bare Soil Cover from NDVI and Rainfall Time Series along the Kalahari Transect, Africa

    Science.gov (United States)

    Scanlon, T. M.; Albertson, J. D.; Caylor, K. K.; Williams, C. A.

    2001-12-01

    Savanna ecosystems are water-limited, a characteristic that can be exploited to estimate fractional cover of trees, grass, and bare soil over large-scale areas from synthesis of remote sensing and rainfall measurements. A method is presented to estimate fractional cover components along the Kalahari Transect (KT), an aridity gradient in southern Africa, based upon the differing ways in which grasses and trees respond to rainfall. Mean wet season normalized difference vegetation index (NDVI) and the sensitivity of the NDVI to variation in wet season rainfall are used as input into a linear unmixing model, and end-members for this analysis are extracted on the basis of best fit to the observed data. The end-members for the mixing analysis are consistent with the qualitative characteristics of trees (high NDVI, low sensitivity of NDVI to interannual variations in rainfall), bare soil (low NDVI, low sensitivity), and the transient grass/ bare soil area (moderate NDVI, high sensitivity). Sensitivity of NDVI to rainfall was based upon the relationship between NDVI and the standardized anomalies, or z-score, of the wet season precipitation, resulting in a 22% improvement in the number of significant relationships (parea is limited by the tree fractional cover on the wetter end of the transect, peaks at approximately 450 mm of mean wet season rainfall, and is limited by rainfall on the more arid portion of the transect. With NDVI for grass inferred from the data, predictions of yearly tree, grass, and bare soil fractional cover can be derived. No calibration or training sets were required for this unmixing procedure, and an additional advantage of this method over traditional unmixing approaches is that cover components can be predicted for future rainfall scenarios. This remote sensing-based model framework, together with a tree/grass interaction submodel, could be used to predict long-term migration of the cover components along this gradient in response to climate

  12. Soil hydraulic parameters and surface soil moisture of a tilled bare soil plot inversely derived from l-band brightness temperatures

    KAUST Repository

    Dimitrov, Marin

    2014-01-01

    We coupled a radiative transfer model and a soil hydrologic model (HYDRUS 1D) with an optimization routine to derive soil hydraulic parameters, surface roughness, and soil moisture of a tilled bare soil plot using measured brightness temperatures at 1.4 GHz (L-band), rainfall, and potential soil evaporation. The robustness of the approach was evaluated using five 28-d data sets representing different meteorological conditions. We considered two soil hydraulic property models: the unimodal Mualem-van Genuchten and the bimodal model of Durner. Microwave radiative transfer was modeled by three different approaches: the Fresnel equation with depth-averaged dielectric permittivity of either 2-or 5-cm-thick surface layers and a coherent radiative transfer model (CRTM) that accounts for vertical gradients in dielectric permittivity. Brightness temperatures simulated by the CRTM and the 2-cm-layer Fresnel model fitted well to the measured ones. L-band brightness temperatures are therefore related to the dielectric permittivity and soil moisture in a 2-cm-thick surface layer. The surface roughness parameter that was derived from brightness temperatures using inverse modeling was similar to direct estimates from laser profiler measurements. The laboratory-derived water retention curve was bimodal and could be retrieved consistently for the different periods from brightness temperatures using inverse modeling. A unimodal soil hydraulic property function underestimated the hydraulic conductivity near saturation. Surface soil moisture contents simulated using retrieved soil hydraulic parameters were compared with in situ measurements. Depth-specific calibration relations were essential to derive soil moisture from near-surface installed sensors. © Soil Science Society of America 5585 Guilford Rd., Madison, WI 53711 USA.

  13. Higher temperature sensitivity for stable than for labile soil organic carbon - Evidence from incubations of long-term bare fallow soils

    DEFF Research Database (Denmark)

    Lefèvre, Romain; Barré, Pierre; Moyano, Fernando E.

    2014-01-01

    soils from LTBF experiments situated at Askov (Denmark), Grignon (France), Ultuna (Sweden), and Versailles (France) and sampled at the start of the experiments and after 25, 50, 52, and 79 years of bare fallow, respectively. Soils were incubated at 4, 12, 20, and 35 °C and the evolved CO2 monitored...... for a general relationship between temperature sensitivity and SOC stability upon which significant improvements in predictive models could be based....

  14. Higher temperature sensitivity for stable than for labile soil organic carbon--evidence from incubations of long-term bare fallow soils.

    Science.gov (United States)

    Lefèvre, Romain; Barré, Pierre; Moyano, Fernando E; Christensen, Bent T; Bardoux, Gérard; Eglin, Thomas; Girardin, Cyril; Houot, Sabine; Kätterer, Thomas; van Oort, Folkert; Chenu, Claire

    2014-02-01

    The impact of climate change on the stability of soil organic carbon (SOC) remains a major source of uncertainty in predicting future changes in atmospheric CO2 levels. One unsettled issue is whether the mineralization response to temperature depends on SOC mineralization rate. Long-term (>25 years) bare fallow experiments (LTBF) in which the soil is kept free of any vegetation and organic inputs, and their associated archives of soil samples represent a unique research platform to examine this issue as with increasing duration of fallow, the lability of remaining total SOC decreases. We retrieved soils from LTBF experiments situated at Askov (Denmark), Grignon (France), Ultuna (Sweden), and Versailles (France) and sampled at the start of the experiments and after 25, 50, 52, and 79 years of bare fallow, respectively. Soils were incubated at 4, 12, 20, and 35 °C and the evolved CO2 monitored. The apparent activation energy (Ea) of SOC was then calculated for similar loss of CO2 at the different temperatures. The Ea was always higher for samples taken at the end of the bare-fallow period, implying a higher temperature sensitivity of stable C than of labile C. Our results provide strong evidence for a general relationship between temperature sensitivity and SOC stability upon which significant improvements in predictive models could be based.

  15. Shallow groundwater effect on land surface temperature and surface energy balance under bare soil conditions: modeling and description

    Directory of Open Access Journals (Sweden)

    F. Alkhaier

    2012-07-01

    Full Text Available Understanding when and how groundwater affects surface temperature and energy fluxes is significant for utilizing remote sensing in groundwater studies and for integrating aquifers within land surface models. To investigate the shallow groundwater effect under bare soil conditions, we numerically exposed two soil profiles to identical metrological forcing. One of the profiles had shallow groundwater. The different responses that the two profiles manifested were inspected regarding soil moisture, temperature and energy balance at the land surface. The findings showed that the two profiles differed in three aspects: the absorbed and emitted amounts of energy, the portioning out of the available energy and the heat fluency in the soil. We concluded that due to their lower albedo, shallow groundwater areas reflect less shortwave radiation and consequently get a higher magnitude of net radiation. When potential evaporation demand is sufficiently high, a large portion of the energy received by these areas is consumed for evaporation. This increases the latent heat flux and reduces the energy that could have heated the soil. Consequently, lower magnitudes of both sensible and ground heat fluxes are caused to occur. The higher soil thermal conductivity in shallow groundwater areas facilitates heat transfer between the top soil and the subsurface, i.e. soil subsurface is more thermally connected to the atmosphere. For the reliability of remote sensors in detecting shallow groundwater effect, it was concluded that this effect can be sufficiently clear to be detected if at least one of the following conditions occurs: high potential evaporation and high contrast between day and night temperatures. Under these conditions, most day and night hours are suitable for shallow groundwater depth detection.

  16. The Effects of GH Transgenic Goats on the Microflora of the Intestine, Feces and Surrounding Soil.

    Directory of Open Access Journals (Sweden)

    Zekun Bao

    Full Text Available The development of genetically engineered animals has brought with it increasing concerns about biosafety issues. We therefore evaluated the risks of growth hormone from transgenic goats, including the probability of horizontal gene transfer and the impact on the microbial community of the goats' gastrointestinal tracts, feces and the surrounding soil. The results showed that neither the GH nor the neoR gene could be detected in the samples. Moreover, there was no significant change in the microbial community of the gastrointestinal tracts, feces and soil, as tested with PCR-denaturing gradient gel electrophoresis and 16S rDNA sequencing. Finally, phylogenetic analysis showed that the intestinal content, feces and soil samples all contained the same dominant group of bacteria. These results demonstrated that expression of goat growth hormone in the mammary of GH transgenic goat does not influence the microflora of the intestine, feces and surrounding soil.

  17. The Effects of GH Transgenic Goats on the Microflora of the Intestine, Feces and Surrounding Soil.

    Science.gov (United States)

    Bao, Zekun; Gao, Xue; Zhang, Qiang; Lin, Jian; Hu, Weiwei; Yu, Huiqing; Chen, Jianquan; Yang, Qian; Yu, Qinghua

    2015-01-01

    The development of genetically engineered animals has brought with it increasing concerns about biosafety issues. We therefore evaluated the risks of growth hormone from transgenic goats, including the probability of horizontal gene transfer and the impact on the microbial community of the goats' gastrointestinal tracts, feces and the surrounding soil. The results showed that neither the GH nor the neoR gene could be detected in the samples. Moreover, there was no significant change in the microbial community of the gastrointestinal tracts, feces and soil, as tested with PCR-denaturing gradient gel electrophoresis and 16S rDNA sequencing. Finally, phylogenetic analysis showed that the intestinal content, feces and soil samples all contained the same dominant group of bacteria. These results demonstrated that expression of goat growth hormone in the mammary of GH transgenic goat does not influence the microflora of the intestine, feces and surrounding soil.

  18. Lead identification in soil surrounding a used lead acid battery smelter area in Banten, Indonesia

    Science.gov (United States)

    Adventini, N.; Santoso, M.; Lestiani, D. D.; Syahfitri, W. Y. N.; Rixson, L.

    2017-06-01

    A used lead acid battery smelter generates particulates containing lead that can contaminate the surrounding environment area. Lead is a heavy metal which is harmful to health if it enters the human body through soil, air, or water. An identification of lead in soil samples surrounding formal and informal used lead acid battery smelters area in Banten, Indonesia using EDXRF has been carried out. The EDXRF accuracy and precision evaluated from marine sediment IAEA 457 gave a good agreement to the certified value. A number of 16 soil samples from formal and informal areas and 2 soil samples from control area were taken from surface and subsurface soils. The highest lead concentrations from both lead smelter were approximately 9 folds and 11 folds higher than the reference and control samples. The assessment of lead contamination in soils described in Cf index was in category: moderately and strongly polluted by lead for formal and informal lead smelter. Daily lead intake of children in this study from all sites had exceeded the recommended dietary allowance. The HI values for adults and children living near both lead smelter areas were greater than the value of safety threshold 1. This study finding confirmed that there is a potential health risk for inhabitants surrounding the used lead acid battery smelter areas in Banten, Indonesia.

  19. Retrieval of Surface and Subsurface Moisture of Bare Soil Using Simulated Annealing

    Science.gov (United States)

    Tabatabaeenejad, A.; Moghaddam, M.

    2009-12-01

    Soil moisture is of fundamental importance to many hydrological and biological processes. Soil moisture information is vital to understanding the cycling of water, energy, and carbon in the Earth system. Knowledge of soil moisture is critical to agencies concerned with weather and climate, runoff potential and flood control, soil erosion, reservoir management, water quality, agricultural productivity, drought monitoring, and human health. The need to monitor the soil moisture on a global scale has motivated missions such as Soil Moisture Active and Passive (SMAP) [1]. Rough surface scattering models and remote sensing retrieval algorithms are essential in study of the soil moisture, because soil can be represented as a rough surface structure. Effects of soil moisture on the backscattered field have been studied since the 1960s, but soil moisture estimation remains a challenging problem and there is still a need for more accurate and more efficient inversion algorithms. It has been shown that the simulated annealing method is a powerful tool for inversion of the model parameters of rough surface structures [2]. The sensitivity of this method to measurement noise has also been investigated assuming a two-layer structure characterized by the layers dielectric constants, layer thickness, and statistical properties of the rough interfaces [2]. However, since the moisture profile varies with depth, it is sometimes necessary to model the rough surface as a layered structure with a rough interface on top and a stratified structure below where each layer is assumed to have a constant volumetric moisture content. In this work, we discretize the soil structure into several layers of constant moisture content to examine the effect of subsurface profile on the backscattering coefficient. We will show that while the moisture profile could vary in deeper layers, these layers do not affect the scattered electromagnetic field significantly. Therefore, we can use just a few layers

  20. Integration of Heat-Pulse and Sensible Heat Balance Methods to Estimate Evaporation From Bare Soils

    Science.gov (United States)

    Trautz, A.; Smits, K. M.; Schulte, P.; Cihan, A.; Illangasekare, T. H.

    2012-12-01

    A critical component of the water cycle at local, regional and global scales is evaporation from soil. Because it is very difficult to measure soil evaporation and soil moisture in the field, with the exception of using a lysimeter for local measurements, numerous model based estimation methods have been proposed. Numerical approaches that attempt to estimate evaporation rates within the top several centimeters of soil often rely of empirical and semi-empirical methods. Another less well known method to determine evaporation relies on heat pulse sensors to measure soil temperature and thermal properties. This approach does not rely on knowledge of soil hydraulic properties, effectively removing the need of several common empirical methods to define the soil surface boundary condition. The objective of this study was to integrate both the heat-pulse and sensible heat balance methods into a non-isothermal multiphase flow model in order to define the boundary conditions at the land/atmosphere interface. This model was tested using precision experimental data collected under laboratory conditions and compared to more traditional numerical modeling approaches. Experimental data was generated in a two-dimensional soil tank containing an array of sensors that allowed soil temperature, soil moisture content, and relative humidity to be collected continuously and autonomously. The soil tank was placed within a wind tunnel test facility to insure that atmospheric conditions were carefully controlled and monitored throughout the duration of the experiment. Numerical results of the model using the heat pulse and sensible heat balance methods were compared to those generated using different, more traditional modeling approaches. Results demonstrate the applicability of incorporating the heat-pulse and sensible heat balance methods in numerical approaches. Further validation was provided through a comparison of the numerical results and independently determined experimental

  1. Effects of tillage on runoff from a bare clayey soil on a semi-arid ...

    African Journals Online (AJOL)

    2010-10-13

    Oct 13, 2010 ... has been used successfully for crop and tree improvement in other parts of the .... Land Type Ab179 (Soil Classification Working Group, 1991). The approximate ..... script and Mrs Memory Mzezewa for field assistance. We are.

  2. Multiphase transport of tritium in unsaturated porous media-bare and vegetated soils

    OpenAIRE

    Jiménez Martínez, Joaquín; Tamoh, Karim; Candela Lledó, Lucila; Elorza, F. J.; Hunkeler, D.

    2012-01-01

    Tritium is a short-lived radioactive isotope (T 1/2=12.33 yr) produced naturally in the atmosphere by cosmic radiation but also released into the atmosphere and hydrosphere by nuclear activities (nuclear power stations, radioactive waste disposal). Tritium of natural or anthropogenic origin may end up in soils through tritiated rain, and may eventually appear in groundwater. Tritium in groundwater can be re-emitted to the atmosphere through the vadose zone. The tritium concentration in soil v...

  3. INTERACTION OF A LONG PILE OF FINITE STIFFNESS WITH SURROUNDING SOIL AND FOUNDATION CAP

    Directory of Open Access Journals (Sweden)

    Ter-Martirosyan Zaven Grigor’evich

    2015-09-01

    Full Text Available The article presents the formulation and analytical solution to a quantification of stress strain state of a two-layer soil cylinder enclosing a long pile, interacting with the cap. The solution of the problem is considered for two cases: with and without account for the settlement of the heel and the underlying soil. In the first case, the article is offering equations for determining the stresses of pile’s body and the surrounding soil according to their hardness and the ratio of radiuses of the pile and the surrounding soil cylinder, as well as formulating for determining equivalent deformation modulus of the system “cap-pile-surrounding soil” (the system. Assessing the carrying capacity of the soil under pile’s heel is of great necessity. In the second case, the article is solving a second-order differential equation. We gave the formulas for determining the stresses of the pile at its top and heel, as well as the variation of stresses along the pile’s body. The article is also formulating for determining the settlement of the foundation cap and equivalent deformation modulus of the system. It is shown that, pushing the pile into underlying layer results in the reducing of equivalent modulus of the system.

  4. Atmospheric emissions of methyl isothiocyanate and chloropicrin following soil fumigation and surface containment treatment in bare-root forest nurseries

    Energy Technology Data Exchange (ETDEWEB)

    Wang, D.; Spokas, K.; Zhang, Y. [Minnesota Univ., St. Paul, MN (United States). Dept. of Soil, Water, and Climate; Juzwik, J. [USDA Forest Service, North Central Research Station, St. Paul, MN (United States); Fraedrich, S.W. [USDA Forest Service, Southern Research Station, Athens, GA (United States); Koskinen, W.C. [USDA Agricultural Research Service, Soil and Water Management Unit, St. Paul, MN (United States)

    2005-05-01

    Bare-root forest nurseries are commonly fumigated to manage pests such as fungal pathogens, nematodes, weeds and insects. Methyl bromide was among the most commonly used fumigants in the 1990s, but it has been found to contribute to the depletion of the ozone layer. Two possible alternatives for soil fumigation are methylisothiocyanate (MITC) and chloropicrin (CP). However, the surface transport of MITC emission has been known to cause seedling damage in adjacent fields at numerous bare-root forest-tree nurseries. In this study, air emissions of MITC and CP were measured after fumigation at nurseries in Wisconsin and Georgia. Four treatments were tested in combinations of 2 fumigants (dazomet or combined application of CP and metam sodium) and 2 surface containment treatments (Tarp or water seal). Less than 5 per cent of the applied equivalent of MITC was lost through surface treatment over a 2-week period. Lower emissions were observed with the water seal. Cumulative emissions of CP accounted for 10 to 22 per cent of the applied CP. Within 1 week following all treatments, more than 70 per cent of total cumulative emissions of MITC or CP occurred. It was concluded that any one of these surface containment treatments can be used at nurseries to reduce the risk of MITC emissions that could harm humans or damage seedling crops in adjacent fields. 44 refs., 2 tabs., 6 figs.

  5. Soil Erosion on a Slope without Vegetation:a Simulating Experiment on a Bare Land in Mt.Tanakami

    Institute of Scientific and Technical Information of China (English)

    ZHAO Wei; HU Ke; KIMOTO Akitsu; MIZUYAMA Takahisa

    2004-01-01

    In order to understand the process of surface erosion and its changing characteristics, a sprinkling experiment is conducted on a bare slope in Mt.Tanakami. Based on the measurements and analysis of runoff, mean soil erosion depth sediment yield and semiment transport, etc., the characteristics in the process of surface erosion in the experimental area are as follows: the occurrence of sediment discharge is interrupted, with a saturated overland-flow surface runoff; the mean erosion depth is 0.086 2 cm, which is thicker compared with other areas in Mt.Tanakmi; sediment yield is 431.283 m3\\5km-2, whose process is detachment-limited, and the type of sediment transport is a sediment flow.

  6. Spatial distribution and accumulation of Hg in soil surrounding a Zn/Pb smelter.

    Science.gov (United States)

    Wu, Qingru; Wang, Shuxiao; Wang, Long; Liu, Fang; Lin, Che-Jen; Zhang, Lei; Wang, Fengyang

    2014-10-15

    Nonferrous metal smelting is an important atmospheric mercury (Hg) emission source that has significant local and global impacts. To quantify the impact of Hg emission from non-ferrous metal smelter on the surrounding soil, an integrated model parameterizing the processes of smelter emission, air dispersion, atmospheric deposition and Hg accumulation in soil was developed. The concentrations of gaseous elemental Hg (GEM) around the smelter and the spatial distribution of Hg in the surrounding soil were measured and compared with the model results. Atmospheric deposition of Hg emitted from the smelter was identified as the main source of Hg accumulation in the surrounding soil. From 1960 to 2011, the smelter emitted approximately 105 t of Hg into the atmosphere, of which 15 t deposited locally and resulted in an increase of Hg concentration in soil from 0.12 to 1.77 mg kg(-1). A detailed examination of wind rose and model data suggested that the area within 1.0-1.5 km northwest and southeast of the smelter was most severely impacted. It was estimated that the smelter operation from 1969 to 1990, when large scale emission controls were not implemented, resulted in 6450 μg m(-2)yr(-1) of Hg net deposition and a model simulated increase of 0.40 mg kg(-1) of Hg accumulation in the soil. During the period from 1991 to 2011, atmospheric Hg emission from the smelter alone increased the average concentration in soil from 0.41 mg kg(-1) to 0.45 mg kg(-1). In the past 50 years, over 86% of Hg emitted from this smelter went into the global pool, indicating the importance of controlling Hg emissions from non-ferrous metal smelters.

  7. On the Soil Roughness Parameterization Problem in Soil Moisture Retrieval of Bare Surfaces from Synthetic Aperture Radar.

    Science.gov (United States)

    Verhoest, Niko E C; Lievens, Hans; Wagner, Wolfgang; Álvarez-Mozos, Jesús; Moran, M Susan; Mattia, Francesco

    2008-07-15

    Synthetic Aperture Radar has shown its large potential for retrieving soil moisture maps at regional scales. However, since the backscattered signal is determined by several surface characteristics, the retrieval of soil moisture is an ill-posed problem when using single configuration imagery. Unless accurate surface roughness parameter values are available, retrieving soil moisture from radar backscatter usually provides inaccurate estimates. The characterization of soil roughness is not fully understood, and a large range of roughness parameter values can be obtained for the same surface when different measurement methodologies are used. In this paper, a literature review is made that summarizes the problems encountered when parameterizing soil roughness as well as the reported impact of the errors made on the retrieved soil moisture. A number of suggestions were made for resolving issues in roughness parameterization and studying the impact of these roughness problems on the soil moisture retrieval accuracy and scale.

  8. Evaporation from Bare Soil in Extremely Arid Environment in Southern Israel

    Institute of Scientific and Technical Information of China (English)

    WANGXUEFENG; XUFUAN; 等

    1996-01-01

    Microlysimeters of different sizes(5cm 10cm and 15cm in length) were used extensively in the present study of the measurements of soil evaporation in situ in an extremely arid area in southern Israel,All of the data obtained from the microlysimeters were used to evaluate two conventional evaporation models developed by Black et al.and Ritchie,respectively.Our results indicated that the models could overestimate total cumulative evaporation by about 30% in the extremely arid environment.Reducing the power factor of the conventional model by a factor of 0.1 produced good agreement between the measured and simulated cumulative evaporation.Microlysimeter method proved to be a simple and accurate approach for the evaluation of soil evaporation.

  9. Soil mercury levels in the area surrounding the Cerro Prieto geothermal complex, MEXICO.

    Science.gov (United States)

    Pastrana-Corral, M A; Wakida, F T; García-Flores, E; Rodriguez-Mendivil, D D; Quiñonez-Plaza, A; Piñon-Colin, T D J

    2016-08-01

    Even though geothermal energy is a renewable energy source that is seen as cost-effective and environmentally friendly, emissions from geothermal plants can impact air, soil, and water in the vicinity of geothermal power plants. The Cerro Prieto geothermal complex is located 30 km southeast of the city of Mexicali in the Mexican state of Baja California. Its installed electricity generation capacity is 720 MW, being the largest geothermal complex in Mexico. The objective of this study was to evaluate whether the emissions generated by the geothermal complex have increased the soil mercury concentration in the surrounding areas. Fifty-four surface soil samples were collected from the perimeter up to an approximate distance of 7660 m from the complex. Additionally, four soil depth profiles were performed in the vicinity of the complex. Mercury concentration in 69 % of the samples was higher than the mercury concentration found at the baseline sites. The mercury concentration ranged from 0.01 to 0.26 mg/kg. Our results show that the activities of the geothermal complex have led to an accumulation of mercury in the soil of the surrounding area. More studies are needed to determine the risk to human health and the ecosystems in the study area.

  10. Metagenomic analysis of bacterial and archaeal assemblages in the soil-mousse surrounding a geothermal spring.

    Science.gov (United States)

    Bhatia, Sonu; Batra, Navneet; Pathak, Ashish; Joshi, Amit; Souza, Leila; Almeida, Paulo; Chauhan, Ashvini

    2015-09-01

    The soil-mousse surrounding a geothermal spring was analyzed for bacterial and archaeal diversity using 16S rRNA gene amplicon metagenomic sequencing which revealed the presence of 18 bacterial phyla distributed across 109 families and 219 genera. Firmicutes, Actinobacteria, and the Deinococcus-Thermus group were the predominant bacterial assemblages with Crenarchaeota and Thaumarchaeota as the main archaeal assemblages in this largely understudied geothermal habitat. Several metagenome sequences remained taxonomically unassigned suggesting the presence of a repertoire of hitherto undescribed microbes in this geothermal soil-mousse econiche.

  11. Soil pollution in Mitrovica town surroundings and absorption of heavy metals by carrot plant

    OpenAIRE

    , Afete Musliu; Seit Shallari

    2013-01-01

    In this paper is studied a heavy meal presence in soil in industrial zone surroundings in Mitrovica town and its impact on the vegetable species, referring on this paper to a carrot. The town of Mitrovica, has the largest complex metallurgy and mining in Europe known as "Trepca", known for exploitation of lead, zinc and cadmium, which town is one of the most polluted cities in Kosovo as in air, soil and water, in particular neighbourhood of industrial zone. The purpose of this work is to make...

  12. Metagenomic analysis of bacterial and archaeal assemblages in the soil-mousse surrounding a geothermal spring

    Directory of Open Access Journals (Sweden)

    Sonu Bhatia

    2015-09-01

    Full Text Available The soil-mousse surrounding a geothermal spring was analyzed for bacterial and archaeal diversity using 16S rRNA gene amplicon metagenomic sequencing which revealed the presence of 18 bacterial phyla distributed across 109 families and 219 genera. Firmicutes, Actinobacteria, and the Deinococcus-Thermus group were the predominant bacterial assemblages with Crenarchaeota and Thaumarchaeota as the main archaeal assemblages in this largely understudied geothermal habitat. Several metagenome sequences remained taxonomically unassigned suggesting the presence of a repertoire of hitherto undescribed microbes in this geothermal soil-mousse econiche.

  13. On the soil roughness parameterization problem in soil moisture retrieval of bare surfaces from Synthetic Aperture Radar 1959

    Science.gov (United States)

    Synthetic Aperture Radar has shown its large potential for retrieving soil moisture maps at regional scales. However, since the backscattered signal is determined by several surface characteristics, the retrieval of soil moisture is an ill-posed problem when using single configuration imagery. Unles...

  14. Mapping bare soil in South West Wales, UK, using high resolution colour infra-red aerial photography for water quality and flood risk management applications

    Science.gov (United States)

    Sykes, Helena; Neale, Simon; Coe, Sarah

    2016-04-01

    Natural Resources Wales is a UK government body responsible for environmental regulation, among other areas. River walks in Water Framework Directive (WFD) priority catchments in South West Wales, UK, identified soil entering water courses due to poaching and bank erosion, leading to deterioration in the water quality and jeopardising the water quality meeting legal minimum standards. Bare soil has also been shown to cause quicker and higher hydrograph peaks in rural catchments than if those areas were vegetated, which can lead to flooding of domestic properties during peak storm flows. The aim was to target farm visits by operational staff to advise on practices likely to improve water quality and to identify areas where soft engineering solutions such as revegetation could alleviate flood risk in rural areas. High resolution colour-infrared aerial photography, 25cm in the three colour bands and 50cm in the near infrared band, was used to map bare soil in seven catchments using supervised classification of a five band stack including the Normalised Difference Vegetation Index (NDVI). Mapping was combined with agricultural land use and field boundary data to filter out arable fields, which are supposed to bare soil for part of their cycle, and was very successful when compared to ground truthing, with the exception of silage fields which contained sparse, no or unproductive vegetation at the time the imagery was acquired leading to spectral similarity to bare soil. A raindrop trace model was used to show the path sediment from bare soil areas would take when moving through the catchment to a watercourse, with hedgerows inserted as barriers following our observations from ground truthing. The findings have been used to help farmers gain funding for improvements such as fencing to keep animals away from vulnerable river banks. These efficient and automated methods can be rolled out to more catchments in Wales and updated using aerial imagery acquired more recently to

  15. Natural radionuclides in soil profiles surrounding the largest coal-fired power plant in Serbia

    Directory of Open Access Journals (Sweden)

    Tanić Milan N.

    2016-01-01

    Full Text Available This study evaluates the influence of the largest Serbian coal-fired power plant on radionuclide concentrations in soil profiles up to 50 cm in depth. Thirty soil profiles were sampled from the plant surroundings (up to 10 km distance and analyzed using standard methods for soil physicochemical properties and gamma ray spectrometry for specific activities of natural radionuclides (40K, 226Ra and 232Th. Spatial and vertical distribution of radionuclides was determined and analyzed to show the relations between the specific activities in the soil and soil properties and the most influential factors of natural radionuclide variability were identified. The radiological indices for surface soil were calculated and radiological risk assessment was performed. The measured specific activities were similar to values of background levels for Serbia. The sampling depth did not show any significant influence on specific activities of natural radionuclides. The strongest predictor of specific activities of the investigated radionuclides was soil granulometry. All parameters of radiological risk assessment were below the recommended values and adopted limits. It appears that the coal-fired power plant does not have a significant impact on the spatial and vertical distribution of natural radionuclides in the area of interest, but technologically enhanced natural radioactivity as a consequence of the plant operations was identified within the first 1.5 km from the power plant. [Projekat Ministarstva nauke Republike Srbije br. III43009 i br. III41005

  16. Increase in soil stable carbon isotope ratio relates to loss of organic carbon: results from five long-term bare fallow experiments

    DEFF Research Database (Denmark)

    Menichetti, Lorenzo; Houot, Sabine; van Oort, Folkert

    2015-01-01

    and covering a latitudinal range of 11°. The bare fallow soils lost 33–65 % of their initial SOC content and showed a mean annual δ13C increase of 0.008–0.024 ‰. The 13C enrichment could be related empirically to SOC losses by a Rayleigh distillation equation. A more complex mechanistic relationship was also...

  17. Dynamics of Water Content in Light Bare Soil in Summer Half-Year in the Period of 2003–2012 and its Agro-Meteorological Determinants

    Directory of Open Access Journals (Sweden)

    Biniak-Pieróg Małgorzata

    2014-10-01

    Full Text Available The objective of the study was the estimation of decade variation of water content in layers with thickness of 0–10, 0–20, 0–40 and 0–60 cm of a bare light brown soil in the summer half-year (May–October in the 10-year period of 2003–2012 against the background of agro-meteorological conditions. The study was based on results of measurement of the moisture of a bare soil with the use of the TDR method, sums of atmospheric precipitations and ground water levels, conducted in the area of the Agro- and Hydrometeorology Observatory of the Wrocław University of Environmental and Life Sciences, situated in Wrocław-Swojec. The analyses revealed slight variation of mean decade values of water content in the bare soil in the summer half-year during the ten-year period under analysis. Irrespective of the thickness of the soil layer, precipitation in the 10-year period of 2003–2012 had a highly significant effect on the water content in the 2nd decade of July. In the case of soil layers with thickness down to 0–20 cm a statistically significant relation between soil water content and ground water levels was noted for the 3rd decade of May, July, and in the 3rd decade of September. In the layer with thickness of 0–60 cm the relations were statistically significant almost throughout the summer half-year, with the exception of the 1st and 2nd decades of May. Analysis of trends of mean water content of the bare soil over the 10-year period of 2003–2012 indicated their statistically significant increase in the case of most of the decades of the summer half-year only in soil layers with thickness of 0–10 and 0–20 cm.

  18. Soil pollution in surroundings of Litija as a reflectionofmining,metallurgy and natural conditions

    Directory of Open Access Journals (Sweden)

    Mateja Gosar

    2007-06-01

    Full Text Available The influence of mining and metallurgic activities as well as natural conditionson heavy metal pollution in Litija and surroundings was defined.Sampling gridinan area of 30 km2 was determined. Soil samples were collected on 120 equally distributed locations in two different depths: horizon A (0–5cm and horizon B (20–30cm.In total researched area concentrations of considered elements in upper soil horizon exceed the official limit concentration on 24km2, warning concentration on 20 km2 and critical concentration on 1.6 km2. Pollution of bottom soil horizon is several times lower. The highest are contents of lead, mercury and arsenic. Areas of enhanced concentrations include a hill Sitarjevec and hill base Podsitarjevec, where the dumps of mining waste and metallurgic slag are situated. Increased concentrations of heavy metals were determined also in the immediate vicinity of former smelter.

  19. Source Identification of Heavy Metals in Soils Surrounding the Zanjan Zinc Town by Multivariate Statistical Techniques

    Directory of Open Access Journals (Sweden)

    M.A. Delavar

    2016-02-01

    Full Text Available Introduction: The accumulation of heavy metals (HMs in the soil is of increasing concern due to food safety issues, potential health risks, and the detrimental effects on soil ecosystems. HMs may be considered as the most important soil pollutants, because they are not biodegradable and their physical movement through the soil profile is relatively limited. Therefore, root uptake process may provide a big chance for these pollutants to transfer from the surface soil to natural and cultivated plants, which may eventually steer them to human bodies. The general behavior of HMs in the environment, especially their bioavailability in the soil, is influenced by their origin. Hence, source apportionment of HMs may provide some essential information for better management of polluted soils to restrict the HMs entrance to the human food chain. This paper explores the applicability of multivariate statistical techniques in the identification of probable sources that can control the concentration and distribution of selected HMs in the soils surrounding the Zanjan Zinc Specialized Industrial Town (briefly Zinc Town. Materials and Methods: The area under investigation has a size of approximately 4000 ha.It is located around the Zinc Town, Zanjan province. A regular grid sampling pattern with an interval of 500 meters was applied to identify the sample location, and 184 topsoil samples (0-10 cm were collected. The soil samples were air-dried and sieved through a 2 mm polyethylene sieve and then, were digested using HNO3. The total concentrations of zinc (Zn, lead (Pb, cadmium (Cd, Nickel (Ni and copper (Cu in the soil solutions were determined via Atomic Absorption Spectroscopy (AAS. Data were statistically analyzed using the SPSS software version 17.0 for Windows. Correlation Matrix (CM, Principal Component Analyses (PCA and Factor Analyses (FA techniques were performed in order to identify the probable sources of HMs in the studied soils. Results and

  20. Estimation of Soil Moisture Content from the Spectral Reflectance of Bare Soils in the 0.4–2.5 µm Domain

    Directory of Open Access Journals (Sweden)

    Sophie Fabre

    2015-02-01

    Full Text Available This work aims to compare the performance of new methods to estimate the Soil Moisture Content (SMC of bare soils from their spectral signatures in the reflective domain (0.4–2.5 µm in comparison with widely used spectral indices like Normalized Soil Moisture Index (NSMI and Water Index SOIL (WISOIL. Indeed, these reference spectral indices use wavelengths located in the water vapour absorption bands and their performance are thus very sensitive to the quality of the atmospheric compensation. To reduce these limitations, two new spectral indices are proposed which wavelengths are defined using the determination matrix tool by taking into account the atmospheric transmission: Normalized Index of Nswir domain for Smc estimatiOn from Linear correlation (NINSOL and Normalized Index of Nswir domain for Smc estimatiOn from Non linear correlation (NINSON. These spectral indices are completed by two new methods based on the global shape of the soil spectral signatures. These methods are the Inverse Soil semi-Empirical Reflectance model (ISER, using the inversion of an existing empirical soil model simulating the soil spectral reflectance according to soil moisture content for a given soil class, and the convex envelope model, linking the area between the envelope and the spectral signature to the SMC. All these methods are compared using a reference database built with 32 soil samples and composed of 190 spectral signatures with five or six soil moisture contents. Half of the database is used for the calibration stage and the remaining to evaluate the performance of the SMC estimation methods. The results show that the four new methods lead to similar or better performance than the one obtained by the reference indices. The RMSE is ranging from 3.8% to 6.2% and the coefficient of determination R2 varies between 0.74 and 0.91 with the best performance obtained with the ISER model. In a second step, simulated spectral radiances at the sensor level are

  1. Sampling and analysis plan for assessment of beryllium in soils surrounding TA-40 building 15

    Energy Technology Data Exchange (ETDEWEB)

    Ruedig, Elizabeth [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-12-19

    Technical Area (TA) 40 Building 15 (40-15) is an active firing site at Los Alamos National Laboratory. The weapons facility operations (WFO) group plans to build an enclosure over the site in 2017, so that test shots may be conducted year-round. The enclosure project is described in PRID 16P-0209. 40-15 is listed on LANL OSH-ISH’s beryllium inventory, which reflects the potential for beryllium in/on soils and building surfaces at 40-15. Some areas in and around 40-15 have previously been sampled for beryllium, but past sampling efforts did not achieve complete spatial coverage of the area. This Sampling and Analysis Plan (SAP) investigates the area surrounding 40-15 via 9 deep (≥1-ft.) soil samples and 11 shallow (6-in.) soil samples. These samples will fill the spatial data gaps for beryllium at 40-15, and will be used to support OSH-ISH’s final determination of 40-15’s beryllium registry status. This SAP has been prepared by the Environmental Health Physics program in consultation with the Industrial Hygiene program. Industrial Hygiene is the owner of LANL’s beryllium program, and will make a final determination with regard to the regulatory status of beryllium at 40-15.

  2. Ecological risk assessment of heavy metals in soils surrounding oil waste disposal areas.

    Science.gov (United States)

    Xu, Jianling; Wang, Hanxi; Liu, Yuanyuan; Ma, Mengchao; Zhang, Tian; Zheng, Xiaoxue; Zong, Meihan

    2016-02-01

    More attention is being devoted to heavy metal pollution because heavy metals can concentrate in higher animals through the food chain, harm human health and threaten the stability of the ecological environment. In this study, the effects of heavy metals (Cu, Cr, Zn, Pb, Cd, Ni and Hg) emanating from oil waste disposal on surrounding soil in Jilin Province, China, were investigated. A potential ecological risk index was used to evaluate the damage of heavy metals and concluded that the degree of potential ecological damage of heavy metals can be ranked as follows: Hg > Cd > Pb > Cu > Ni > Cr > Zn. The average value of the potential ecological harm index (Ri) is 71.93, thereby indicating light pollution. In addition, this study researched the spatial distribution of soil heavy metals by means of ArcGIS (geographic information system) spatial analysis software. The results showed that the potential ecological risk index (R) of the large value was close to the distance from the oil waste disposal area; it is relatively between the degree of heavy metals in soil and the distance from the waste disposal area.

  3. Impact of mine tailings on surrounding soils and ground water: Case of Kettara old mine, Morocco

    Science.gov (United States)

    El Amari, K.; Valera, P.; Hibti, M.; Pretti, S.; Marcello, A.; Essarraj, S.

    2014-12-01

    The old ochre-pyrrhotite mine of Kettara, near Marrakech (Morocco) ceased operating some 30 years ago but its excavations, plants, and tailings have been totally abandoned since then. Geochemical analyses of the soils, stream sediments and waters of the surrounding area were carried out to assess the pollution impact of this mining site. Tailing characterization showed the presence of sulphide primary minerals, as well as secondary ones containing among others (Fe, S, Cu, Pb, Zn, Cd, Ni, Cr, Co, As, Se). In spite of the presence of theses pollutants in the Acid Mine Drainage (AMD) of Kettara, groundwater did not show significant levels of these metals probably related to the low ion circulation under the local dry climate with low annual rainfall that prevents metal ion circulation. The chemical analyses of soil and stream sediment samples included elements most of which are internationally considered as dangerous for human health (As, Cd, Co, Cr, Cu, Fe, Ni, Pb, S, Se and Zn). Geochemical maps of these elements showed that Cr and Ni were linked to mafic intrusions of Kettara sector. Sulphur is linked to the mining activity and the others are related both to lithological outcrops and mining activity. However, the levels of these contaminants did not exceed Italian Standards of soil pollution.

  4. Development and evaluation of an efficient soil-atmosphere model (FHAVeT) based on the Ross fast solution of the Richards equation for bare soil conditions

    Science.gov (United States)

    Tinet, A.-J.; Chanzy, A.; Braud, I.; Crevoisier, D.; Lafolie, F.

    2015-02-01

    In agricultural management, a good timing in operations, such as irrigation or sowing, is essential to enhance both economical and environmental performance. To improve such timing, predictive software are of particular interest. Optimal decision-software would require process modules which provide robust, efficient and accurate predictions while being based on a minimal amount of parameters easily available. The objective of this study is to assess the accuracy of a physically based model with high efficiency. To this aim, this paper develops a coupled model with climatic forcing based on the Ross fast solution for Richards' equation, heat transfer and detailed surface energy balance. The present study is limited to bare soil, but the impact of vegetation can be easily included. The developed model, FHAVeT (Fast Hydro Atmosphere Vegetation Temperature), is evaluated against the coupled model based on the Philip and De Vries (1957) description, TEC. The two models were compared for different climatic and soil conditions. Moreover, the model allows using various pedotransfer functions. The FHAVeT model showed better performance in regards to mass balance, mostly below 0.002 m, and generally improved computation time. In order to allow for a more precise comparison, six time windows were selected. The study demonstrated that the FHAVeT behaviour is quite similar to the TEC behaviour except under some dry conditions. The ability of the models to detect the occurrence of soil intermediate water content thresholds with a 1 day tolerance was also evaluated. Both models agreed in more than 90% of the cases.

  5. Lithological and land-use based assessment of heavy metal pollution in soils surrounding a cement plant in SW Europe.

    Science.gov (United States)

    Cutillas-Barreiro, Laura; Pérez-Rodríguez, Paula; Gómez-Armesto, Antía; Fernández-Sanjurjo, María José; Álvarez-Rodríguez, Esperanza; Núñez-Delgado, Avelino; Arias-Estévez, Manuel; Nóvoa-Muñoz, Juan Carlos

    2016-08-15

    We study the influence of phasing out a cement plant on the heavy metal (Hg, Pb and Cr) content in the surrounding soils, taking into account factors often neglected, such as contributions due to local lithology or land use. The range of total Hg was 10-144µg kg(-1), reaching up to 41 and 145mgkg(-1) for total contents of Pb and Cr, respectively. Forest soils showed higher concentration of Hg than prairie soils, indicating the importance of land use on the accumulation of volatile heavy metals in soils. In forest soils, total Hg showed a trend to decrease with soil depth, whereas in prairie soils the vertical pattern of heavy metal concentrations was quite homogeneous. In most cases, the distance to the cement plant was not a factor of influence in the soils content of the analyzed heavy metals. Total Pb and Cr contents in soils nearby the cement plant were quite similar to those found in the local lithology, resulting in enrichment factor values (EF's) below 2. This suggests that soil parent material is the main source of these heavy metals in the studied soils, while the contribution of the cement plant to Pb and Cr soil pollution was almost negligible. On the contrary, the soils surrounding the cement plant accumulate a significant amount of Hg, compared to the underlying lithology. This was especially noticeable in forest soils, where Hg EF achieved values up to 36. These results are of relevance, bearing in mind that Hg accumulation in soils may be an issue of environmental concern, particularly in prairie soils, where temporal flooding can favor Hg transformation to highly toxic methyl-Hg. In addition, the concurrence of acid soils and total-Cr concentrations in the range of those considered phytotoxic should be also stressed.

  6. Estimating photosynthetic vegetation, non-photosynthetic vegetation and bare soil fractions using Landsat and MODIS data: Effects of site heterogeneity, soil properties and land cover

    Science.gov (United States)

    Guerschman, J. P.; Scarth, P.; McVicar, T.; Malthus, T. J.; Stewart, J.; Rickards, J.; Trevithick, R.; Renzullo, L. J.

    2013-12-01

    Vegetation fractional cover is a key indicator for land management monitoring, both in pastoral and agricultural settings. Maintaining adequate vegetation cover protects the soil from the effects of water and wind erosion and also ensures that carbon is returned to soil through decomposition. Monitoring vegetation fractional cover across large areas and continuously in time needs good remote sensing techniques underpinned by high quality ground data to calibrate and validate algorithms. In this study we used Landsat and MODIS reflectance data together with field measurements from 1476 observations across Australia to produce estimates of vegetation fractional cover using a linear unmixing technique. Specifically, we aimed at separating fractions of photosynthetic vegetation (PV), non-photosynthetic vegetation (NPV) and bare soil (B). We used Landsat reflectance averaged over a 3x3 pixel window representing the area actually measured on the ground and also a 'degraded' Landsat reflectance 40x40 pixel window to simulate the effect of a coarser sensor. Using these two Landsat reflectances we quantified the heterogeneity of each site. We used data from two MODIS-derived reflectance products: the Nadir BRDF-Adjusted surface Reflectance product (MCD43A4) and the MODIS 8-day surface reflectance (MOD09A1). We derived endmembers from the data and estimated fractional cover using a linear unmixing technique. Log transforms and band interaction terms were added to account for non-linearities in the spectral mixing. For each reflectance source we investigated if the residuals were correlated with site heterogeneity, soil colour, soil moisture and land cover type. As expected, the best model was obtained when Landsat data for a small region around each site was used. We obtained root mean square error (RMSE) values of 0.134, 0.175 and 0.153 for PV, NPV and B respectively. When we degraded the Landsat data to an area of ~1 km2 around each site the model performance decreased to

  7. Research on the Horizontal Displacement Coefficient of Soil Surrounding Pile in Layered Foundations by Considering the Soil Mass’s Longitudinal Continuity

    Directory of Open Access Journals (Sweden)

    Yao Wen-Juan

    2013-01-01

    Full Text Available When utilizing the p-y curve to simulate the nonlinear characteristics of soil surrounding pile in layered foundations, due to having not taken into account the soil mass’s longitudinal continuity, the calculation deviation of horizontal displacement increases with the growth of a load. This paper adopted the layered elasticity system theory to consider the soil mass’s longitudinal continuity, as well as utilizing the research method for layered isotropic bodies, assuming that the horizontal resistance is evenly distributed around the perimeter of the pile's cross-section. Then an appropriate transfer matrix method of horizontal displacement coefficient for the soil surrounding pile in layered foundations was established. According to the calculation principle of finite element equivalent load, the horizontal displacement coefficient matrix was deduced as well as providing a corrected formula for the horizontal displacement of soil surrounding pile through the p-y curve method when the external load was increased. Following the established model, a program was created which was used for calculating and analyzing the horizontal displacement coefficient matrix of three-layered soil in order to verify this method’s validity and rationale. Where there is a relatively large discrepancy in the soil layers’ properties, this paper’s method is able to reflect the influence on the layered soil’s actual distributional difference as well as the nearby soil layers’ interaction.

  8. Concentrations, sources and spatial distribution of polycyclic aromatic hydrocarbons in soils from Beijing, Tianjin and surrounding areas, North China

    Energy Technology Data Exchange (ETDEWEB)

    Wang Wentao [Laboratory for Earth Surface Processes, College of Urban and Environmental Sciences, Peking University, Beijing 100871 (China); Department of Environmental and Molecular Toxicology, Oregon State University, Corvallis, OR 97331 (United States); Massey Simonich, Staci L. [Department of Environmental and Molecular Toxicology, Oregon State University, Corvallis, OR 97331 (United States); Department of Chemistry, Oregon State University, Corvallis, OR 97331 (United States); Xue Miao; Zhao Jingyu; Zhang Na; Wang Rong; Cao Jun [Laboratory for Earth Surface Processes, College of Urban and Environmental Sciences, Peking University, Beijing 100871 (China); Tao Shu, E-mail: taos@urban.pku.edu.c [Laboratory for Earth Surface Processes, College of Urban and Environmental Sciences, Peking University, Beijing 100871 (China)

    2010-05-15

    The concentrations, profiles, sources and spatial distribution of polycyclic aromatic hydrocarbons (PAHs) were determined in 40 surface soil samples collected from Beijing, Tianjin and surrounding areas, North China in 2007, and all sampling sites were far from industrial areas, roadsides and other pollution sources, and across a range of soil types in remote, rural villages and urban areas. The total concentrations of 16 PAHs ranged from 31.6 to 1475.0 ng/g, with an arithmetic average of 336.4 ng/g. The highest PAH concentrations were measured in urban soils, followed by rural village soils and soils from remote locations. The remote-rural village-urban PAH concentration gradient was related to population density, gross domestic product (GDP), long-range atmospheric transport and different types of land use. In addition, the PAH concentration was well correlated with the total organic carbon (TOC) concentration of the soil. The PAH profile suggested that coal combustion and biomass burning were primary PAH sources. - The concentration, profiles and possible sources of PAHs in Beijing, Tianjin and surrounding area soils were studied and related to population density and gross domestic product (GDP).

  9. Metagenomic analysis exploring taxonomic and functional diversity of soil microbial communities in Chilean vineyards and surrounding native forests

    Science.gov (United States)

    2017-01-01

    Mediterranean biomes are biodiversity hotspots, and vineyards are important components of the Mediterranean landscape. Over the last few decades, the amount of land occupied by vineyards has augmented rapidly, thereby increasing threats to Mediterranean ecosystems. Land use change and agricultural management have important effects on soil biodiversity, because they change the physical and chemical properties of soil. These changes may also have consequences on wine production considering that soil is a key component of terroir. Here, we describe the taxonomic diversity and metabolic functions of bacterial and fungal communities present in forest and vineyard soils in Chile. To accomplish this goal, we collected soil samples from organic vineyards in central Chile and employed a shotgun metagenomic approach to sequence the microbial DNA. Additionally, we studied the surrounding native forest to obtain a baseline of the soil conditions in the area prior to the establishment of the vineyard. Our metagenomic analyses revealed that both habitats shared most of the soil microbial species. The most abundant genera in the two habitats were the bacteria Candidatus Solibacter and Bradyrhizobium and the fungus Gibberella. Our results suggest that the soil microbial communities are similar in these forests and vineyards. Therefore, we hypothesize that native forests surrounding the vineyards may be acting as a microbial reservoir buffering the effects of the land conversion. Regarding the metabolic diversity, we found that genes pertaining to the metabolism of amino acids, fatty acids, and nucleotides as well as genes involved in secondary metabolism were enriched in forest soils. On the other hand, genes related to miscellaneous functions were more abundant in vineyard soils. These results suggest that the metabolic function of microbes found in these habitats differs, though differences are not related to taxonomy. Finally, we propose that the implementation of

  10. Brominated flame retardants in the surrounding soil of two manufacturing plants in China: Occurrence, composition profiles and spatial distribution.

    Science.gov (United States)

    Li, Wen-Long; Liu, Li-Yan; Zhang, Zi-Feng; Song, Wei-Wei; Huo, Chun-Yan; Qiao, Li-Na; Ma, Wan-Li; Li, Yi-Fan

    2016-06-01

    Surface soil samples were collected surrounding two brominated flame retardants (BFRs) manufacturing plants in China in August 2014 and analyzed for 23 polybrominated diphenyl ethers (PBDEs) and 8 novel brominated flame retardants (NBFRs). BDE209 and decabromodiphenylethane (DBDPE) were the predominant compounds in soil with the median levels of 1600 and 560 ng/g dw, respectively. The PBDEs profiles in soil samples were consistent with that of commercial product (comDecaBDE). The percentage contributions to total PBDEs decreased from higher to lower brominated homologues. Lower concentrations of NBFRs (excluding DBDPE) were detected in soil surrounding the two plants, suggesting they are byproducts or degradation products of the manufacturing activities. The concentrations of most BFRs dropped exponentially within 3-5 km of the manufacturing plants, suggesting recent deposition of these compounds to the soil. Directional distribution indicated that PBDEs and DBDPE concentrations were highest in the north direction of Plants 1. Three-day air parcel forward trajectories confirmed that the air parcel was responsible for the higher concentration of BFRs in the soil of north direction of the plant.

  11. 454 Pyrosequencing-based assessment of bacterial diversity and community structure in termite guts, mounds and surrounding soils.

    Science.gov (United States)

    Makonde, Huxley M; Mwirichia, Romano; Osiemo, Zipporah; Boga, Hamadi I; Klenk, Hans-Peter

    2015-01-01

    Termites constitute part of diverse and economically important termite fauna in Africa, but information on gut microbiota and their associated soil microbiome is still inadequate. In this study, we assessed and compared the bacterial diversity and community structure between termites' gut, their mounds and surrounding soil using the 454 pyrosequencing-based analysis of 16S rRNA gene sequences. A wood-feeder termite (Microcerotermes sp.), three fungus-cultivating termites (Macrotermes michaelseni, Odontotermes sp. and Microtermes sp.), their associated mounds and corresponding savannah soil samples were analyzed. The pH of the gut homogenates and soil physico-chemical properties were determined. The results indicated significant difference in bacterial community composition and structure between the gut and corresponding soil samples. Soil samples (Chao1 index ranged from 1359 to 2619) had higher species richness than gut samples (Chao1 index ranged from 461 to 1527). The bacterial composition and community structure in the gut of Macrotermes michaelseni and Odontotermes sp. were almost identical but different from that of Microtermes and Microcerotermes species, which had unique community structures. The most predominant bacterial phyla in the gut were Bacteroidetes (40-58 %), Spirochaetes (10-70 %), Firmicutes (17-27 %) and Fibrobacteres (13 %) while in the soil samples were Acidobacteria (28-45 %), Actinobacteria (20-40 %) and Proteobacteria (18-24 %). Some termite gut-specific bacterial lineages belonging to the genera Dysgonomonas, Parabacteroides, Paludibacter, Tannerella, Alistipes, BCf9-17 termite group and Termite Treponema cluster were observed. The results not only demonstrated a high level of bacterial diversity in the gut and surrounding soil environments, but also presence of distinct bacterial communities that are yet to be cultivated. Therefore, combined efforts using both culture and culture-independent methods are suggested to

  12. Shallow groundwater effect on land surface temperature and surface energy balance under bare soil conditions: modeling and description

    Directory of Open Access Journals (Sweden)

    F. Alkhaier

    2011-09-01

    Full Text Available Appreciating when and how groundwater affects surface temperature and energy fluxes is important for utilizing remote sensing in groundwater studies and for integrating aquifers within land surface models. To explore the shallow groundwater effect, we numerically exposed two soil profiles – one having shallow groundwater – to the same meteorological forcing, and inspected their different responses regarding surface soil moisture, temperature and energy balance. We found that the two profiles differed in the absorbed and emitted amounts of energy, in portioning out the available energy and in heat fluency within the soil. We conclude that shallow groundwater areas reflect less shortwave radiation due to their lower albedo and therefore they get higher magnitude of net radiation. When potential evaporation demand is high enough, a large portion of the energy received by these areas is spent on evaporation. This makes the latent heat flux predominant, and leaves less energy to heat the soil. Consequently, this induces lower magnitudes of both sensible and ground heat fluxes. The higher soil thermal conductivity in shallow groundwater areas facilitates heat transfer between the top soil and the subsurface, i.e. soil subsurface is more thermally connected to the atmosphere. In view of remote sensors' capability of detecting shallow groundwater effect, we conclude that this effect can be sufficiently clear to be sensed if at least one of two conditions is met: high potential evaporation and big contrast in air temperature between day and night. Under these conditions, most day and night hours are suitable for shallow groundwater depth detection.

  13. Application of a coupled microwave, energy and water transfer model to relate passive microwave emission from bare soils to near-surface water content and evaporation

    Directory of Open Access Journals (Sweden)

    L. P. Simmonds

    1999-01-01

    Full Text Available The paper examines the stability of the relation between microwave emission from the soil and the average near-surface water content in the case of relatively smooth, bare soils, and then considers the extent to which microwave radiometry can be used to estimate the effective surface resistance to vapour transfer, which is also related to the near-surface water status. The analysis is based on the use of a model (MICRO-SWEAT which couples a microwave radiative transfer model with a SVAT scheme that describes the exchanges of water vapour, energy and sensible heat at the land surface. Verification of MICRO-SWEAT showed good agreement (about 3K RMSE between predicted L band (1.4 GHz brightness temperature over soils with contrasting texture during a multi-day drydown, and those measured using a truck-mounted radiometer. There was good agreement between the measured and predicted relations between the average water content of the upper 2 cm of the soil profile and the brightness temperature normalised with respect to the radiometric surface temperature. Some of the scatter in this relationship was attributable to diurnal variation in the magnitude of near-surface gradients in temperature and water content, and could be accounted for by using the physically-based simulation model. The influence of soil texture on this relationship was well-simulated using MICRO-SWEAT. The paper concludes by demonstrating how MICRO-SWEAT can be used to establish a relationship between the normalised brightness temperature and the surface resistance for use in the prediction of evaporation using the Penman-Montheith equation.

  14. SOILS AND GEOENVIRONMENTS OF THE NATIONAL PARK OF VIRUÁ AND SURROUNDING, RORAIMA: INTEGRATED VISION OF THE LANDSCAPE AND ENVIRONMENTAL SERVICE

    Directory of Open Access Journals (Sweden)

    Bruno Araujo Furtado de Mendonça

    2013-06-01

    Full Text Available http://dx.doi.org/10.5902/198050989287The Viruá National Park (PARNA Viruá occupies 227.011ha, in the region of the low ‘Branco’ river, in Roraima state. This area includes an extensive mosaic of complex seasonally flooded forested and non-forested environments. The present work had as general objective to characterize the pedology aspects and the geo-environmental units of the Park and surroundings, in an integrated vision of the landscape and, additionally, estimate the carbon stocks in the soils and geo-environments. We described and collected 29 soil profiles in the main vegetation types of Campinaranas and Forests of PARNA Viruá and surroundings. The main soil classes are: Espodossolo Humilúvico, Neossolo Quartzarênico, Neossolo Flúvico, Neossolo Litólicos, Latossolo Vermelho-Amarelo, Latossolo Vermelho, Cambissolo Háplico, Cambissolo Flúvico, Gleissolo Háplico and Plintossolo Háplico. The soils present spatial distribution marked by abrupt limits and close association with the vegetation type. We identified three pedo-environments: (1 sandy soils of the Campinaranas; (2 soils associated with the inselbergs and adjacencies; and (3 alluvial soils. We mapped and described 18 geoenvironmental units in PARNA Viruá National Park. The main geo-environments are: i Sandy plains and Paleodunes with grassy and arborous Campinarana on ‘Neossolos Quartzarênicos hidromórficos’ and ‘Espodossolos’; and Floodplains and; ii Terraces with Igapó Forest on sandy hydromorphic soils, occupying 24.6% and 20.1% of the studied area, respectively. In terms of total soil carbon stocks, the geo-environments of the sandy complexes of Campinaranas and associations stand out, with 9450.9 Gg C. The great extension and representativeness of the sandy areas of Campinaranas characterize PARNA Viruá PArk as an important conservation unit for protection Amazonian sandy soil systems. The areas under the domain of ‘Espodossolos’ possess the

  15. Concentrations, sources and spatial distribution of polycyclic aromatic hydrocarbons in soils from Beijing, Tianjin and surrounding areas, North China

    Science.gov (United States)

    Wang, Wentao; Massey Simonich, Staci L.; Xue, Miao; Zhao, Jingyu; Zhang, Na; Wang, Rong; Cao, Jun; Tao, Shu

    2013-01-01

    The concentrations, profiles, sources and spatial distribution of polycyclic aromatic hydrocarbons (PAHs) were determined in 40 surface soil samples collected from Beijing, Tianjin and surrounding areas, North China in 2007, and all sampling sites were far from industrial areas, roadsides and other pollution sources, and across a range of soil types in remote, rural villages and urban areas. The total concentrations of 16 PAHs ranged from 31.6 to 1475.0 ng/g, with an arithmetic average of 336.4 ng/g. The highest PAH concentrations were measured in urban soils, followed by rural village soils and soils from remote locations. The remote–rural village–urban PAH concentration gradient was related to population density, gross domestic product (GDP), long-range atmospheric transport and different types of land use. In addition, the PAH concentration was well correlated with the total organic carbon (TOC) concentration of the soil. The PAH profile suggested that coal combustion and biomass burning were primary PAH sources. PMID:20199833

  16. Concentrations, sources and spatial distribution of polycyclic aromatic hydrocarbons in soils from Beijing, Tianjin and surrounding areas, North China

    Energy Technology Data Exchange (ETDEWEB)

    Wang, W.T.; Simonich, S.L.M.; Xue, M.A.; Zhao, J.Y.; Zhang, N.; Wang, R.; Cao, J.; Tao, S. [Peking University, Beijing (China)

    2010-05-15

    The concentrations, profiles, sources and spatial distribution of polycyclic aromatic hydrocarbons (PAHs) were determined in 40 surface soil samples collected from Beijing, Tianjin and surrounding areas, North China in 2007, and all sampling sites were far from industrial areas, roadsides and other pollution sources, and across a range of soil types in remote, rural villages and urban areas. The total concentrations of 16 PAHs ranged from 31.6 to 1475.0 ng/g, with an arithmetic average of 336.4 ng/g. The highest PAH concentrations were measured in urban soils, followed by rural village soils and soils from remote locations. The remote-rural village-urban PAH concentration gradient was related to population density, gross domestic product (GDP), long-range atmospheric transport and different types of land use. In addition, the PAH concentration was well correlated with the total organic carbon (TOC) concentration of the soil. The PAH profile suggested that coal combustion and biomass burning were primary PAH sources.

  17. Research on the stability analysis and design of soil tunnel surrounding rock

    Institute of Scientific and Technical Information of China (English)

    Zheng Yingren; Qiu Chenyu; Xiao Qiang

    2010-01-01

    The paper first analyzes the failure mechanism and mode of tunnel according to model experiments and mechanical calculation and then discusses the deficiency of taking the limit value of displacement around the tunnel and the size of the plastic zone of surrounding rock as the criterion of stability.So the writers put forward the idea that the safety factor of surrounding rock calculated through strength reduction FEM(finit element method)should be regarded as the criterion of stability,which has strict mechanical basis and unified standard and would not be influenced by other factors.The paper also studies the safety factors of tunnel surrounding rock(safety factors of shear and tension failure)and lining and some methods of designing and calculating tunnels.At last,the writers take the loess tunnel for instance and show the design and calculation results of two-lane railway tunnel.

  18. RELATIONSHIP AMONG EVAPORATION FLUX OF GROUNDWATER, DEPTH OF WATER TABLE AND NEGATIVE PRESSURE HEAD IN BARE SOIL

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Evaporation of ground water is a part of moisture circulation in the field.And it is a main natural form in which water transmits from the ground water to the soil water and atmosphere water.According to the simulated experiments, we study the relationship among the evaporation, depth of groundwater table and negative pressure.By theoretical analysis of the experimental results, the main conclusions are drawn as follows.There are two abrupt points in every Q-H curve.The locations of the abrupt points are separately in step with the height of top of the capillary fringe and the height of maximal capillary rise in the soil section.When the depth of ground water table H is small, the evaporation flux of ground water is large.While the depth of water table exceeds the maximal capillary rise of media in vadose zone, the capillary rise breaks up and evaporation flux of groundwater is small.The water content ratio in ground surface tends to be zero and the surface of soil tends to be drought.These conclusions show that the maximal capillary rise of media in vadose zone is an important value in regulating rational depth of ground water to reduce the evaporation of ground water and to increase effective quantity of water resources.In the meantime, these conclusions are of important theoretical and practical significance to reduce the evaporation of ground water, to prevent and cure the salinization of soil, and to make full use of and protect water resources in the northern plains in China.

  19. Regional differences and sources of organochlorine pesticides in soils surrounding chemical industrial parks

    NARCIS (Netherlands)

    Wang, G.; Lu, Y.L.; Li, J.; Wang, T.Y.; Han, Jingyi; Luo, W.; Shi, Y.J.; Jiao, W.T.

    2009-01-01

    Concentrations of organochlorine pesticides (OCPs; dichlorodiphenyltrichloroethanes (DDTs), hexachlorocyclohexanes (HCHs), hexachlorobenzene (HCB)) were investigated in 105 soil samples collected in vicinity of the chemical industrial parks in Tianjin, China. OCP concentrations significantly varied

  20. Bacterial diversity in the rhizosphere of maize and the surrounding carbonate-rich bulk soil.

    Science.gov (United States)

    García-Salamanca, Adela; Molina-Henares, M Antonia; van Dillewijn, Pieter; Solano, Jennifer; Pizarro-Tobías, Paloma; Roca, Amalia; Duque, Estrella; Ramos, Juan L

    2013-01-01

    Maize represents one of the main cultivar for food and energy and crop yields are influenced by soil physicochemical and climatic conditions. To study how maize plants influence soil microbes we have examined microbial communities that colonize maize plants grown in carbonate-rich soil (pH 8.5) using culture-independent, PCR-based methods. We observed a low proportion of unclassified bacteria in this soil whether it was planted or unplanted. Our results indicate that a higher complexity of the bacterial community is present in bulk soil with microbes from nine phyla, while in the rhizosphere microbes from only six phyla were found. The predominant microbes in bulk soil were bacteria of the phyla Acidobacteria, Bacteroidetes and Proteobacteria, while Gammaproteobacteria of the genera Pseudomonas and Lysobacter were the predominant in the rhizosphere. As Gammaproteobacteria respond chemotactically to exudates and are efficient in the utilization of plants exudate products, microbial communities associated to the rhizosphere seem to be plant-driven. It should be noted that Gammaproteobacteria made available inorganic nutrients to the plants favouring plant growth and then the benefit of the interaction is common.

  1. Continuum-scale investigation of evaporation from bare soil under different boundary and initial conditions: An evaluation of nonequilibrium phase change

    Science.gov (United States)

    Trautz, Andrew C.; Smits, Kathleen M.; Cihan, Abdullah

    2015-09-01

    Evaporation and condensation in bare soils govern water and energy fluxes between the land and atmosphere. Phase change between liquid water and water vapor is commonly evaluated in soil hydrology using an assumption of instantaneous phase change (i.e., chemical equilibrium). Past experimental studies have shown that finite volatilization and condensation times can be observed under certain environmental conditions, thereby questioning the validity of this assumption. A comparison between equilibrium and nonequilibrium phase change modeling approaches showed that the latter is able to provide better estimates of evaporation, justifying the need for more research on this topic. Several formulations based on irreversible thermodynamics, first-order reaction kinetics, or the kinetic theory of gases have been employed to describe nonequilibrium phase change at the continuum scale. In this study, results from a fully coupled nonisothermal heat and mass transfer model applying four different nonequilibrium phase change formulations were compared with experimental data generated under different initial and boundary conditions. Results from a modified Hertz-Knudsen formulation based on kinetic theory of gases, proposed herein, were consistently in best agreement in terms of preserving both magnitude and trends of experimental data under all environmental conditions analyzed. Simulation results showed that temperature-dependent formulations generally better predict evaporation than formulations independent of temperature. Analysis of vapor concentrations within the porous media showed that conditions were not at equilibrium under the experimental conditions tested.

  2. Hydrocarbon and Carbon Dioxide Fluxes from Natural Gas Well Pad Soils and Surrounding Soils in Eastern Utah.

    Science.gov (United States)

    Lyman, Seth N; Watkins, Cody; Jones, Colleen; Mansfield, Marc L; McKinley, Michael; Kenney, Donna; Evans, Jordan

    2017-09-07

    We measured fluxes of methane, non-methane hydrocarbons, and carbon dioxide from natural gas well pad soils and from nearby undisturbed soils in eastern Utah. Methane fluxes varied from less than zero to more than 38 g m-2 h-1. Fluxes from well pad soils were almost always greater than from undisturbed soils. Fluxes were greater from locations with higher concentrations of total combustible gas in soil and were inversely correlated with distance from well heads. Several lines of evidence show that the majority of emission fluxes (about 70%) were primarily due to subsurface sources of raw gas that migrated to the atmosphere, with the remainder likely caused primarily by re-emission of spilled liquid hydrocarbons. Total hydrocarbon fluxes during summer were only 39 (16, 97)% as high as during winter, likely because soil bacteria consumed the majority of hydrocarbons during summer months. We estimate that natural gas well pad soils account for 4.6×10-4 (1.6×10-4, 1.6×10-3)% of total emissions of hydrocarbons from the oil and gas industry in Utah's Uinta Basin. Our undisturbed soil flux measurements were not adequate to quantify rates of natural hydrocarbon seepage in the Uinta Basin.

  3. Determination of Total Chromium and Chromium Species in Kombolcha Tannery Wastewater, Surrounding Soil, and Lettuce Plant Samples, South Wollo, Ethiopia

    Directory of Open Access Journals (Sweden)

    Tilahun Belayneh Asfaw

    2017-01-01

    Full Text Available This research paper deals with the determination of total chromium (total Cr, Cr(III, and Cr(VI in Kombolcha leather industrial wastewater and the surrounding (soil and lettuce plant samples where the wastewater flows. The levels of total Cr, Cr(VI, and Cr(III in wastewater, soil, and lettuce plant samples were determined by FAAS, UV/Vis spectrophotometer, and difference (Cr(VI from total Cr, respectively. Among all samples taken, the maximum amounts of total Cr, Cr(III, and Cr(VI were obtained at the discharging point and the minimum amounts of total Cr and Cr(III were found downstream (400 m from the junction of Kombolcha leather industrial wastewater. On the other hand, the minimum concentration of Cr(VI was obtained in lettuce plant sample. The amounts of total Cr in all samples except soil sample were above the permissible limit as set by WHO/FAO. The concentrations of Cr(III in all wastewater samples were above the permissible level, whereas the concentration of Cr(VI in wastewater was above the permissible level except 400 m from the junction. The result showed that a remarkable elimination of total Cr and Cr species has not been achieved by this leather industry as its level was not much decreased when entered into the water systems. Therefore, effective treatment methods should be applied to the wastewater for the wellbeing of the surroundings.

  4. Activity and population dynamics of heterotrophic and ammonia-oxidizing microorganisms in soil surrounding sludge bands spiked with linear alkylbenzene sulfonate

    DEFF Research Database (Denmark)

    Brandt, K. K.; Sørensen, J.; Krogh, P. H.

    2003-01-01

    Recent research has documented soil microorganisms to be rather sensitive to linear alkylbenzene sulfonates (LAS), which may enter the soil environment in considerable quantities following sewage sludge disposal. We here report field effects of LAS on selected microbial populations present...... in a sandy soil surrounding well-defined sludge bands spiked with high but realistic LAS levels (7.1 or 31.3 g/kg). Surprisingly, LAS had no effect on heterotrophic respiration in the sludge compartment per se but stimulated activity and metabolic quotient (microbial activity per unit of biomass......) in the surrounding soil. By contrast, autotrophic ammonia oxidation was initially inhibited in the LAS-spiked sludge. This led to dramatic transient increases of NH+4 availability in the sludge and surrounding soil, subsequently stimulating soil ammonia oxidizers. As judged from a Nitrosomonas europaea...

  5. Geochemical properties of soils surrounding the Deliklitaş Au deposit, Turkey

    Science.gov (United States)

    Kirat, Güllü; Aydin, Nasuh

    2016-08-01

    The Deliklitaş gold deposit is in northwest Turkey, where a renowned gold province containing many major hydrothermal deposits related to Tertiary volcanic rocks. Because of the limited outcrops in the region, one of the most effective ways to prospect for new deposits is soil sampling. In this study, 183 soil samples were systematically collected from the area around the Deliklitaş Au deposit. Metal content of the samples, and their relationships and distribution according to distance away from the ore body were statistically investigated. The analysis of metals and metalloids in soil samples yielded the following metal ranges: Au from 0.005 to 0.54 mg/kg (average 0.04); Ag from 0.03 to 2.66 (average 0.22); As from 3.4 to 315 (average 30.3); Sb from 0.15 to 19.25 (average 1.62); Cu from 2.5 to 35 (average 11.73); Pb from 17.4 to 545 (average 73.76) and from Zn 14-1240 mg/kg of soil (average 106.71). For the areal distribution of metals 50%, 70%, 90% and 95% of the cumulative data were used for contouring element contents in the soils, using 50% as the baseline value and 95% as the anomalous value. Eigen values, Varimax Rotation method with Kaiser Normalization tested and determined the suitability of the number of data sets. Factor numbers were determined as 3, according to Eigen values determined for the soil samples. Factor 1 refers to ore minerals of epithermal system, Factor 2 refers to main rock sources of Pb and Zn and Factor 3 refers to environmental effects. Agsbnd Au, Pbsbnd Zn and Sbsbnd As pairs show high correlation in the cluster analysis indicating element relations. Please add an overarching sentence here, on implications etc.

  6. Extraction of Bare Soil Features from SPOT-5 Imagery Based on NDSI and NDISI%基于NDSI和NDISI指数的SPOT-5影像裸土信息提取

    Institute of Scientific and Technical Information of China (English)

    李霞; 徐涵秋; 李晶; 郭燕滨

    2016-01-01

    The accurate mapping of bare soil land is of vital significance to soil erosion treatment. Satellite remote sensing has become a popular technology used in bare soil mapping, owing to the capability of monitoring bare soil dynamics in a cost-effective manner. Nowadays, Landsat imagery with a spatial resolution of 30 m has been widely used in previous work for bare soil extraction. Nevertheless, due to the limitation of its spatial resolution, the Landsat image can hardly meet the requirement of fine-scale bare soil mapping. Thus, a method for higher resolution bare soil mapping was proposed in this paper using SPOT-5 imagery as the main data. The Normalized Difference Soil Index (NDSI) was firstly utilized to enhance the bare soil features from the SPOT-5multispectral 10 m image. However, the enhanced soil information was mixed with the built-up land features due to the confusion between the two categories. To solve this problem, the Normalized Difference Impervious Surface Index (NDISI) was further introduced to separate the built-up features from the bare soils. Due to the lack of a thermal band in SPOT-5 imagery, which is required in computing NDISI, a near synchronous Landsat TM thermal band 6 was fine-sharpened to 10 m resolution, and afterwards, it was added to the SPOT-5 bands to calculate NDISI. Accordingly, a model was used in mapping the bare soil, based on the NDSI and NDISI. Finally, the extraction results of bare soil at 10 m resolution were obtained through the model, which achieved an overall accuracy of 95.4%. It suggests that the two-index based method can effectively eli-minate the confusion between bare soil land and built-up land, and can extract the bare soil features with a higher accuracy. In addition, the bare soil features extracted from SPOT imagery and TM imagery respectively, were further compared. It is found that a higher spatial resolution can lead to a more accurate extraction result. Therefore, the 10 m resolution SPOT-5 image is

  7. Distribution coefficients of different soil types at Olkiluoto repository site and its surroundings, southwestern Finland

    Energy Technology Data Exchange (ETDEWEB)

    Lahdenperae, Anne-Maj [Saanio and Riekkola Oy, Laulukuja 4, FI-00420 Helsinki (Finland); Ikonen, Ari T.K. [Environmental Research and Assessment EnviroCase, Ltd., Hallituskatu 1 D 4, 28100 Pori (Finland)

    2014-07-01

    In Finland, the Olkiluoto Island on the western coast has been selected as a repository site for the spent nuclear fuel. Due to shallow sea areas around the island, the post-glacial crustal rebound (around 6 mm/y) is changing the landscape significantly; during the next thousands of years new soil types are emerging, the present bays will narrow and form future lakes and mires assumedly similar to those farther inland at present. The effects of terrain development are important in long-term safety assessments for the repository, especially in the biosphere assessments addressing radiation exposure of people and biota in scenarios of radionuclide releases. 'In situ' distribution coefficients, K{sub d} values are used to indicate the relevant mobility of radionuclides of concern from nuclear waste. These radionuclides have very long half-lives and long interaction times with soils, ranging from centuries to millennia. By measuring the desorption K{sub d} values of the indigenous stable elements (Ag, Cl, Cs, I, Mo, Nb, Ni, Se and Sr) from field moist samples are a valid description of slow retention processes. The 'in situ' K{sub d} desorption values are calculated for humus, peat and different mineral soil samples taken from the Olkiluoto Island and the Reference Area used as an analogue of the future terrain. The solids are extracted alternatively by HNO{sub 3}-HF and NH{sub 4}Ac (pH 4.5). The K{sub d} values are highly dependent on environmental factors, including but not limited to pH, soil type, soil horizon, soil body, texture, element chemical form, organic matter, carbon content and biological activity. This is discussed in the contribution; e.g., for several elements pH and K{sub d} values correlate - the finer the soil or sediment, the higher the K{sub d} values - and humus and peat samples have a clear correlation with the organic matter and carbon contents. The contribution also compares the 'in situ' K{sub d} values to

  8. Swelling soils monitoring through PSI and DINSAR interferometry : Applications on eastern Paris surroundings (France)

    Science.gov (United States)

    Kaveh, F.; Deffontaines, B.; Fruneau, B.; Cojean, R.; Audiguier, M.; Arnaud, A.; Duro, J.

    2009-04-01

    Swelling soils may induce small surface displacements under various climatic conditions, that may affect individual buildings. The aim of this work, funded by MAIF foundation (Insurance foundation), is to monitor those small seasonal-dependant displacements through DINSAR and persistent scatterer interferometric methods. The eastern paris basin is locally composed of outcropping Marne de Pantin and Argiles Vertes particularily sensible to swelling phenomena observed during for instance the last dryness event of 2003. Radar differential interferometry (DINSAR) method which enables one to map surface displacements from two radar images acquired on a specific area gives rather poor results and is not that efficient in the eastern Paris Basin highly due to the temporal decorrelation. On the contrary, interesting results are obtained with Persistent Scatterer Interferometry (PSI) which reveal precisely the surface displacements, continuous in time. This new application of interferometry presents high potential to better understand the swelling soil natural hazards and the induced geologic processes.

  9. Trace Metals in Surface Soil Contaminated by Release of Phosphate Industry in the Surroundings of Sfax-Tunisia

    Directory of Open Access Journals (Sweden)

    Ahmed Wali

    2013-10-01

    Full Text Available There is a worldwide growing concern about soil pollution caused by phosphate industry creating thus large amounts of phosphogypsum slurry. This slurry is piped from the processing facilities up into acidic wastewater ponds that sit atop the mountainous waste piles known as gypsum stacks. This issue is of special interest because of toxic metals threats to groundwater tables as well as to the surrounding environment.There is a worldwide growing concern about soil pollution caused by phosphate industry creating thus large amounts of phosphogypsum slurry. This slurry is piped from the processing facilities up into acidic wastewater ponds that sit atop the mountainous waste piles known as gypsum stacks. This issue is of special interest because of toxic metals threats to groundwater tables as well as to the surrounding environment.The aim of the present work is to assess the level of trace elements content in soil around stocked solid waste “a phosphogypsum” derived from a former phosphate fertilizers factory and to investigate their factors of variation. Twenty soil samples were collected at the depths of 20 cm and analyzed for their physicochemical properties, the content of their major elements (Ca, Mg, K, Na, Al, Fe, Mn, and some trace elements such as Zn, Pb, Cr, Cu, Co and Ni. Data were processed with multivariate statistical analysis in order to investigate relationships among the trace elements and the factors controlling their distribution in the phosphogypsum surrounding environment. Enrichment factors (EF were calculated to assess either natural and/or anthropogenic origins. The results indicate moderate levels of contamination and big differences in variability among elements. The maximal and mean concentrations found in soil, except the soil sample S5.1, were 95.2 and 36.5 mg Kg-1 for Zn, 75.2 and 30.23 mg Kg-1 for Pb, 28.4 and 17.5 mg Kg-1 for Cr, 61.9 and 15.6 mg Kg-1 for Cu, 5.28 and 2.7 mg Kg-1 for Co, and 13.2 and 6.4 mg Kg-1

  10. Diversity of microorganisms isolated from the soil sample surround Chroogomphus rutilus in the Beijing region

    DEFF Research Database (Denmark)

    Wang, P; Liu, Y; Yin, Y

    2011-01-01

    to isolate and classify beneficial microorganisms that could affect its growth, which could be used in future research on artificial cultivation. In total, 342 isolates were isolated from soil samples collected around a C. rutilus colony in the Beijing region. Of these, 22 bacterial and 14 fungal isolates....... Using internal transcribed spacer (ITS) sequence analysis, fungal isolates were divided into four monophyletic clusters: Penicillium, Trichoderma, Mortierella, and Bionectria. Moreover, the phylogenetic diversity of these isolates was analysed. The results indicated that numerous microorganisms were...

  11. Contents of metals Pb, Cd, Zn and Cu in Agricultural Soils of Zagreb and Its Surroundings

    Directory of Open Access Journals (Sweden)

    Marija Romić

    1998-09-01

    The highest average cadmium content of 0.93 mg/kg Cd per designated regions was recorded in the youngest river valley along the Sava. Anomalous values were also encountered in the youngest valley along the Sava watercourse, where the average zinc content amounted to 87.08 mg/kg Zn, which are classified as highly contaminated soils. Higher copper values were determined in the hilly area of Mt. Medvednica and Pleistocene of sloping terrains, which seems to be related to the manner of land use (vineyards, gardens at private holdings.

  12. [Concentration levels and spatial distribution of heavy metals in soil surrounding a municipal solid waste incineration plant (Shenzhen)].

    Science.gov (United States)

    Wang, Jun-Jian; Zhao, Hong-Wei; Zhong, Xiu-Ping; Liu, Yang-Sheng; Zeng, Hui

    2011-01-01

    The municipal solid waste (MSW) incineration has been well known among key sources of heavy metal (HM) emission. To investigate the multivariate relationships and spatial distribution of HMs from this source, 9 HMs (Hg, As, Cd, Cr, Cu, Ni, Pb, Se and Zn) were analysed by multivariate statistical analysis in 80 representative soil samples including surface soils and subsurface soils around the Shenzhen Qingshuihe MSW Incineration Plant (MSWIP). Results show that, the concentrations of Hg, As, Cd, Cr, Cu, Ni, Pb, Se and Zn range 0.012-0.136, 0.23-75.89, not detected (ND)-1.17, 21.7-116.0, ND-61.1, ND-47.0, ND-133.0, ND-16.4 and 8.6-246.9 mg x kg(-1), respectively. No significant elevation of concentrations of HMs in soils is observed, compared with the natural background. Based on the hierarchical cluster and historical analysis, the spatial correlations of HMs have been changed by the impact of MSWIP. According to the similarity of concentration, the HMs can be divided into 3 categories: (1) Cu, Ni, Cr, Se, Zn, Pb; (2) As, Cd; (3) Hg. Factors analysis was also performed and shows that the HM distribution patterns are dominantly affected by 3 principal components: local biogeochemical characteristics (48.6% of variance), impact of the MSWIP (16.6% of variance) as well as topographical characteristics (13.2% of variance). Subsequently the 3 maps of factor scores are calculated and exhibited. This study favors to estimate the long-term effects of HM emission from MSWIP on surrounding soil environment and facilitate the local health risk assessment.

  13. Superficial soil erosion assessment in agricultural land and bare land using {sup 7}Be fallout; Estudo da redistribuicao de solo superficial em areas cultivadas e nao cultivadas utilizando o fallout do {sup 7}Be

    Energy Technology Data Exchange (ETDEWEB)

    Marestoni, Luiz Diego

    2007-02-15

    Geologic and hydrologic phenomenon monitoring presents great environmental and financial interest and several radioisotopes, natural and artificial, have been used for this purpose. The more used are {sup 137}Cs, {sup 210}Pb not supported and {sup 7}Be. In the present work, {sup 7}Be was used to determine the soil erosion in three areas: one with soy ploughed at the direction of the slope, one with it perpendicular to the slope and one in an area with bare soil. {sup 7}Be is a cosmogenic radionuclide, with half-life of 53.3 days, produced by spallation of oxygen and nitrogen by cosmic rays in the troposphere and stratosphere. {sup 7}Be deposition occurs by dry and wet deposition, although wet deposition contributed by 95%. This can be verified through the measures of the {sup 7}Be inventory correlated with the precipitation, which resulted in a good linear adjustment. The experimental set up consisted of two HPGe detectors: one with 66% of relative efficiency and one with 10% of relative efficiency, both detectors coupled to standard gamma ray spectrometry nuclear electronic chain. Soil samples were packed in 1 liter Marinelli beckers. Sampling was accomplished until the depth where {sup 7}Be was present and it was possible to verify that its penetration in the soils could be very well adjusted by an exponential type function. The maximum beryllium-7 penetration in the bare soil without sign of soil erosion was 3 cm, that is, beryllium-7 is a useful tool as tracer for superficial soil erosion determination. The constant of mass relaxation h{sub 0} was determined as 4.71 {+-} 0.36, result that is in agreement with other works in the international literature. It was verified that when the soy is ploughed perpendicular to the slope, the soil redistribution rate is smaller, resulting in economic advantage. The bare soil is very exposed to the erosion, because does not exist any barrier to contain the soil that flows at the direction of the slope, such fact was verified

  14. Diversity of soil fungal communities of Cerrado and its closely surrounding agriculture fields.

    Science.gov (United States)

    de Castro, Alinne Pereira; Quirino, Betania Ferraz; Pappas, Georgios; Kurokawa, Adriane Silva; Neto, Eduardo Leonardecz; Krüger, Ricardo Henrique

    2008-08-01

    Cerrado is a savanna-like region that covers a large area of Brazil. Despite its biological importance, the Cerrado has been the focus of few microbial diversity studies. A molecular approach was chosen to characterize the soil fungal communities in four areas of the Cerrado biome: a native Cerrado, a riverbank forest, an area converted to a soybean plantation, and an area converted to pasture. Global diversity of fungal communities in each area was assessed through Ribosomal intergenic spacer analysis which revealed remarkable differences among the areas studied. Sequencing of approximately 200 clones containing 18S rDNA sequences from each library was performed and, according to the genetic distance between sequences, these were assigned to operational taxonomic units (OTUs). A total of 75, 85, 85, and 70 OTUs were identified for the native Cerrado, riverbank forest, pasture, and soybean plantation, respectively. Analysis of sequences using a similarity cutoff value of 1% showed that the number of OTUs for the native Cerrado area was reduced by 35%; for the soybean plantation, a reduction by more than 50% was observed, indicating a reduction in fungal biodiversity associated with anthropogenic activity. This is the first study demonstrating the anthropogenic impact on Cerrado soil fungal diversity.

  15. Mercury pollution in vegetables, grains and soils from areas surrounding coal-fired power plants

    Science.gov (United States)

    Li, Rui; Wu, Han; Ding, Jing; Fu, Weimin; Gan, Lijun; Li, Yi

    2017-05-01

    Mercury contamination in food can pose serious health risks to consumers and coal-fired power plants have been identified as the major source of mercury emissions. To assess the current state of mercury pollution in food crops grown near coal-fired power plants, we measured the total mercury concentration in vegetables and grain crops collected from farms located near two coal-fired power plants. We found that 79% of vegetable samples and 67% of grain samples exceeded the PTWI's food safety standards. The mercury concentrations of soil samples were negatively correlated with distances from the studied coal-fired power plants, and the mercury contents in lettuce, amaranth, water spinach, cowpea and rice samples were correlated with the mercury contents in soil samples, respectively. Also, the mercury concentrations in vegetable leaves were much higher than those in roots and the mercury content of vegetable leaves decreased significantly after water rinses. Our calculation suggests that probable weekly intake of mercury for local residents, assuming all of their vegetables and grains are from their own farmland, may exceed the toxicologically tolerable values allowed, and therefore long-term consumptions of these contaminated vegetables and grains may pose serious health risks.

  16. Factor analysis of rock, soil and water geochemical data from Salem magnesite mines and surrounding area, Salem, southern India

    Science.gov (United States)

    Satyanarayanan, M.; Eswaramoorthi, S.; Subramanian, S.; Periakali, P.

    2017-09-01

    Geochemical analytical data of 15 representative rock samples, 34 soil samples and 55 groundwater samples collected from Salem magnesite mines and surrounding area in Salem, southern India, were subjected to R-mode factor analysis. A maximum of three factors account for 93.8 % variance in rock data, six factors for 84 % variance in soil data, five factors for 71.2 % in groundwater data during summer and six factors for 73.7 % during winter. Total dissolved solids are predominantly contributed by Mg, Na, Cl and SO4 ions in both seasons and are derived from the country rock and mining waste by dissolution of minerals like magnesite, gypsum, halite. The results also show that groundwater is enriched in considerable amount of minor and trace elements (Fe, Mn, Ni, Cr and Co). Nickel, chromium and cobalt in groundwater and soil are derived from leaching of huge mine dumps deposited by selective magnesite mining activity. The factor analysis on trivalent, hexavalent and total Cr in groundwater indicates that most of the Cr in summer is trivalent and in winter hexavalent. The gradational decrease in topographical elevation from northern mine area to the southern residential area, combined regional hydrogeological factors and distribution of ultramafic rocks in the northern part of the study area indicate that these toxic trace elements in water were derived from mine dumps.

  17. Factor analysis of rock, soil and water geochemical data from Salem magnesite mines and surrounding area, Salem, southern India

    Science.gov (United States)

    Satyanarayanan, M.; Eswaramoorthi, S.; Subramanian, S.; Periakali, P.

    2016-04-01

    Geochemical analytical data of 15 representative rock samples, 34 soil samples and 55 groundwater samples collected from Salem magnesite mines and surrounding area in Salem, southern India, were subjected to R-mode factor analysis. A maximum of three factors account for 93.8 % variance in rock data, six factors for 84 % variance in soil data, five factors for 71.2 % in groundwater data during summer and six factors for 73.7 % during winter. Total dissolved solids are predominantly contributed by Mg, Na, Cl and SO4 ions in both seasons and are derived from the country rock and mining waste by dissolution of minerals like magnesite, gypsum, halite. The results also show that groundwater is enriched in considerable amount of minor and trace elements (Fe, Mn, Ni, Cr and Co). Nickel, chromium and cobalt in groundwater and soil are derived from leaching of huge mine dumps deposited by selective magnesite mining activity. The factor analysis on trivalent, hexavalent and total Cr in groundwater indicates that most of the Cr in summer is trivalent and in winter hexavalent. The gradational decrease in topographical elevation from northern mine area to the southern residential area, combined regional hydrogeological factors and distribution of ultramafic rocks in the northern part of the study area indicate that these toxic trace elements in water were derived from mine dumps.

  18. Diversity of microorganisms isolated from the soil sample surround Chroogomphus rutilus in the Beijing region

    DEFF Research Database (Denmark)

    Wang, P; Liu, Y; Yin, Y;

    2011-01-01

    to isolate and classify beneficial microorganisms that could affect its growth, which could be used in future research on artificial cultivation. In total, 342 isolates were isolated from soil samples collected around a C. rutilus colony in the Beijing region. Of these, 22 bacterial and 14 fungal isolates....... Using internal transcribed spacer (ITS) sequence analysis, fungal isolates were divided into four monophyletic clusters: Penicillium, Trichoderma, Mortierella, and Bionectria. Moreover, the phylogenetic diversity of these isolates was analysed. The results indicated that numerous microorganisms were......Artificially cultivating Chroogomphus rutilus is too inefficient to be commercially feasible. Furthermore, isolating C. rutilus mycelia in the wild is difficult. Thus, it is important to de-termine the natural habitat of its fruiting body. This study focused on the ecology of the C. rutilus habitat...

  19. Diversity of Microorganisms Isolated from the Soil Sample surround Chroogomphus rutilus in the Beijing Region

    Directory of Open Access Journals (Sweden)

    Peng Wang, Yu Liu, Yonggang Yin, Haojie Jin, Shouxian Wang, Feng Xu, Shuang Zhao, Xiaoli Geng

    2011-01-01

    Full Text Available Artificially cultivating Chroogomphus rutilus is too inefficient to be commercially feasible. Furthermore, isolating C. rutilus mycelia in the wild is difficult. Thus, it is important to determine the natural habitat of its fruiting body. This study focused on the ecology of the C. rutilus habitat to isolate and classify beneficial microorganisms that could affect its growth, which could be used in future research on artificial cultivation. In total, 342 isolates were isolated from soil samples collected around a C. rutilus colony in the Beijing region. Of these, 22 bacterial and 14 fungal isolates were selected for sequencing and phylogenetic analysis, based on their growth characteristics and colony morphology. Using 16S rRNA gene sequence analysis, the bacterial isolates were divided into two monophyletic clusters which had significant hits to the genera Bacillus and Pseudomonas, respectively. Using internal transcribed spacer (ITS sequence analysis, fungal isolates were divided into four monophyletic clusters: Penicillium, Trichoderma, Mortierella, and Bionectria. Moreover, the phylogenetic diversity of these isolates was analysed. The results indicated that numerous microorganisms were present in C. rutilus habitat. This was the first reported examination of the microbiological ecology of C. rutilus.

  20. Activity and population dynamics of heterotrophic and ammonia-oxidizing microorganisms in soil surrounding sludge bands spiked with linear alkylbenzene sulfonate: a field study.

    Science.gov (United States)

    Brandt, Kristian Koefoed; Krogh, Paul Henning; Sørensen, Jan

    2003-04-01

    Recent research has documented soil microorganisms to be rather sensitive to linear alkylbenzene sulfonates (LAS), which may enter the soil environment in considerable quantities following sewage sludge disposal. We here report field effects of LAS on selected microbial populations present in a sandy soil surrounding well-defined sludge bands spiked with high but realistic LAS levels (7.1 or 31.3 g/kg). Surprisingly, LAS had no effect on heterotrophic respiration in the sludge compartment per se but stimulated activity and metabolic quotient (microbial activity per unit of biomass) in the surrounding soil. By contrast, autotrophic ammonia oxidation was initially inhibited in the LAS-spiked sludge. This led to dramatic transient increases of NH4+ availability in the sludge and surrounding soil, subsequently stimulating soil ammonia oxidizers. As judged from a Nitrosomonas europaea bioluminescence toxicity assay, however, LAS or other sludge components never accumulated to toxic levels in the soil compartments and the LAS tolerance of the indigenous microbes further remained unchanged following LAS exposure. LAS effects on the investigated microbial populations largely occurred during the first two months and were confined to soil closer than 30 mm from LAS-spiked sludge. Our results strongly suggest that disposal of LAS-contaminated sludge does not pose a major risk to the function of the soil microbial community under field conditions.

  1. 红壤裸露坡地次降雨土壤侵蚀规律%Regularity of individual rainfall soil erosion in bare slope land of red soil

    Institute of Scientific and Technical Information of China (English)

    秦伟; 左长清; 晏清洪; 王昭艳; 杜鹏飞; 燕楠

    2015-01-01

    It is valuable for soil and water loss control and its benefits evaluation to understand the relationship between rainfall and soil erosion process. In order to make clear what rainfall type accelerates soil erosion on slopes of red soil in south part of China, and to ascertain the response of soil erosion intensity to rainfall characteristic under various rainfall types, data of meteorology and hydrology of 134 individual rainfalls in experimental plots on bare slopes of red soil in north part of Jiangxi Province were collected and analyzed. The amount, duration and intensity of rainfall were selected as the characteristic indices for erosive rainfall. Two methods including quick clustering and discriminant clustering were introduced to classify the rainfall types resulting in soil erosion. Pearson correlation analysis was then used to find the main indices that contributed the most to the slope soil erosion. Further, Mann-Kendall test and the other statistics method were used to determine the relationship between soil erosion intensity and the rainfall characteristic indices under different rainfall types. The results showed that the erosive rainfall in north part of Jiangxi Province could be classified into three types: type A (high frequency, short duration, minor amount of rainfall, and strong rainfall intensity), type B (medium frequency, medium duration, medium amount of rainfall, and medium rainfall intensity) and type C (low frequency, long duration, great amount of rainfall, and low rainfall intensity). Soil erosion on bare slopes of red soil in south part of China was mainly caused by type A. During the process of individual rainfall, soil erosion on bare slopes of red soil was mainly affected by the joint influences of rainfall intensity and amount, the former resulted in erosion change directly through the closest index - maximum 30 min rainfall intensity, the latter had indirectly effects by changing the former. With the increase of maximum 30 min

  2. Radioactive influence of some phosphogypsum piles located at the SW Spain in their surrounding soils and salt-marshes

    Science.gov (United States)

    Bolivar, J. P.; Mosqueda, F.; Vaca, F.; Garcia-Tenorio, R.; Martinez-Sanchez, M. J.; Perez-Sirvent, C.; Martinez-Lopez, S.

    2012-04-01

    In the SW of Spain, just in the confluence of the mouths of the Tinto and Odiel River and in the vicinity of Huelva town, there is a big industrial complex which includes between others an industry devoted during more than 40 years to the production of phosphoric acid, by treating sedimentary phosphate rock by the so-called "wet acid method". As a by-product of the mentioned process it have been produced historically huge amounts of a compound called phosphogypsum, which composition is mostly di-hydrate calcium sulphate containing some of the impurities of heavy metals and natural radionuclides originally present in the raw material. Due to the lack of market for this by-product, it has been mostly piled over some salt-marshes located in the vicinity of the industry, on the bank of the Tinto River. About 100 million tons of phosphogypsum have been piled in an area covering more than 1000 hectares, constituting a clear environmental and radiological anomaly in the zone. The phosphogypsum piles set do not conform obviously a close system. They are interacting with the nearby environment mostly by leaching waters releases from the waters accumulated in them either for its previous use in transporting in suspension the PG from the factory or by rainfall. These waters leaks contain in solution enhanced amounts of heavy metals and radionuclides that can provoke the chemical and radioactive contamination in surroundings soil and salt-marshes areas. In this communication the radioactive influence by the phosphogypsum piles in the surrounding terrestrial environment is evaluated. This contamination is mostly due to radionuclides belonging to the uranium series, which are present originally in the raw material treated in the industry, and afterwards in the generated phosphogypsum, in enhanced amounts in relation to typical soils. In addition, the different dynamics and behavior of different radionuclides will be discussed and analyzed. The gained information in this study

  3. Lead, arsenic, and polycyclic aromatic hydrocarbons in soil and house dust in the communities surrounding the Sydney, Nova Scotia, tar ponds.

    OpenAIRE

    Lambert, Timothy W; Lane, Stephanie

    2004-01-01

    This study evaluated lead, arsenic, and polycyclic aromatic hydrocarbon (PAH) contamination in the residential communities adjacent to the Sydney, Nova Scotia, tar ponds, the area considered Canada's worst contaminated site. The tar pond remediation policy has been limited to the site and some residential properties. We compared background concentrations in 91 soil samples taken 5-20 km from the coke oven site with those in soil samples from the three communities surrounding the tar ponds: Wh...

  4. On barely continuous functions

    Directory of Open Access Journals (Sweden)

    Richard Stephens

    1988-01-01

    Full Text Available The term barely continuous is a topological generalization of Baire-1 according to F. Gerlits of the Mathematical Institute of the Hungarian Academy of Sciences, and thus worthy of further study. This paper compares barely continuous functions and continuous functions on an elementary level. Knowing how the continuity of the identity function between topologies on a given set yields the lattice structure for those topologies, the barely continuity of the identity function between topologies on a given set is investigated and used to add to the structure of that lattice. Included are certain sublattices generated by the barely continuity of the identity function between those topologies. Much attention is given to topologies on finite sets.

  5. Study of enhanced bare land index using Landsat ETM+ image

    Science.gov (United States)

    Dou, P.; Chen, Y.

    2016-12-01

    For most bare land index without considering the spectrum similarity between high reflectivity buildings and bare land on the ETM+ remote sensing image, this paper has proposed bareness area index(BAI) and short bareness area index(SBAI) by analysing the spectrum characteristics of high reflectivity buildings and bare land. The impact of vegetation and water body to BAI and SBAI was decreased by using SAVI(Soil Adjusted Vegetation Index) and MNDWI(Modified Normalized Difference Water Index). Based on BAI and SBAI, we also used IBI(Index-based Built-up Index) to build enhanced bare land index. Bare land differences between BAI and IBI, SBAI and IBI were stretched by using an exponential function. Imitating NDVI, EBAI(Enhanced Bareness Area Index) and ESBAI(Enhanced Short Bareness Area Index) was constructed. And finally a statistical analysis indicates that EBAI and ESBAI can make bare land positive and background object negative, and comparing most other bare land index, these tow index have higher accuracy and are more easier to find a threshold to separate bare land and other land use type while effectively suppressing noise.

  6. Dispersion of Short- and Medium-Chain Chlorinated Paraffins (CPs) from a CP Production Plant to the Surrounding Surface Soils and Coniferous Leaves.

    Science.gov (United States)

    Xu, Jiazhi; Gao, Yuan; Zhang, Haijun; Zhan, Faqiang; Chen, Jiping

    2016-12-06

    Chlorinated paraffin (CP) production is one important emission source for short- and medium-chain CPs (SCCPs and MCCPs) in the environment. In this study, 48 CP congener groups were measured in the surface soils and coniferous leaves collected from the inner and surrounding environment of a CP production plant that has been in operation for more than 30 years to investigate the dispersion and deposition behavior of SCCPs and MCCPs. The average concentrations of the sum of SCCPs and MCCPs in the in-plant coniferous leaves and surface soils were 4548.7 ng g(-1) dry weight (dw) and 3481.8 ng g(-1) dw, which were 2-fold and 10-fold higher than those in the surrounding environment, respectively. The Gaussian air pollution model explained the spatial distribution of CPs in the coniferous leaves, whereas the dispersion of CPs to the surrounding surface soils fits the Boltzmann equation well. Significant fractionation effect was observed for the atmospheric dispersion of CPs from the production plant. CP congener groups with higher octanol-air partitioning coefficients (KOA) were more predominant in the in-plant environment, whereas the ones with lower KOA values had the elevated proportion in the surrounding environment. A radius of approximately 4 km from the CP production plant was influenced by the atmospheric dispersion and deposition of CPs.

  7. Application of ecological risk assessment based on a novel TRIAD-tiered approach to contaminated soil surrounding a closed non-sealed landfill.

    Science.gov (United States)

    Gutiérrez, Laura; Garbisu, Carlos; Ciprián, Estela; Becerril, José M; Soto, Manu; Etxebarria, Javier; Madariaga, Juan M; Antigüedad, Iñaki; Epelde, Lur

    2015-05-01

    The Ecological Risk Assessment (ERA) is a reliable tool for communicating risk to decision makers in a comprehensive and scientific evidence-based way. In this work, a site-specific ERA methodology based on the TRIAD approach was applied to contaminated soil surrounding a closed non-sealed landfill, as a case study to implement and validate such ERA methodology in the Basque Country (northern Spain). Initially, the procedure consisted of the application of a Parameter Selection Module aimed at selecting the most suitable parameters for the specific characteristics of the landfill contaminated soil, taking into consideration the envisioned land use, intended ecosystem services and nature of contaminants. Afterwards, the selected parameters were determined in soil samples collected from two sampling points located downstream of the abovementioned landfill. The results from these tests were normalized to make them comparable and integrable in a risk index. Then, risk assessment criteria were developed and applied to the two landfill contaminated soil samples. Although the lack of a proper control soil was evidenced, a natural land use was approved by the ERA (at Tier 2) for the two landfill contaminated soils. However, the existence of a potential future risk resulting from a hypothetical soil acidification must be considered.

  8. The Globe laid bare

    CERN Multimedia

    Fortunati, Lucien

    2015-01-01

    If you’re at CERN at the moment, you will certainly have noticed the work under way on the Globe. The structure, which has been in pride of place opposite the Laboratory for over ten years, has never been so completely laid bare. But, as we explained in a previous article (see here), it is all for a good cause. The Globe is built entirely from wood and certain parts of it need to be replaced.

  9. The Globe laid bare

    CERN Multimedia

    Fortunati, Lucien

    2015-01-01

    If you’re at CERN at the moment, you will certainly have noticed the work under way on the Globe. The structure, which has been in pride of place opposite the Laboratory for over ten years, has never been so completely laid bare. But, as we explained in a previous article (see here), it is all for a good cause. The Globe is built entirely from wood and certain parts of it need to be replaced.

  10. Multi-factors influencing the spatial distribution of polycyclic aromatic hydrocarbons in soils surrounding drinking water protection zone.

    Science.gov (United States)

    Jiao, Wentao; Wang, Tieyu; Lu, Yonglong; Chang, Andrew; Chen, Weiping

    2013-08-01

    We selected the Guanting Reservoir in Beijing, China as a case where an industrial area locates on the upwind corner to study the influence of human activities and natural processes on the distribution of polycyclic aromatic hydrocarbons (PAHs) in soils. Soil PAH concentrations in the study area follow a log-normal probability distribution function, suggesting that distribution of PAH in soils was affected by human activities. Distribution of PAHs in soils was significantly affected by the point source that high PAH concentrations were observed in near industrial area with an obvious declining trend from the northwest to the southeast which was the prevailing wind direction in this area. Away from the influence of point source, distribution of PAHs in soils was found to significantly correlate with total organic carbon content, while the influences of agricultural land uses and type of soil texture on the total soil PAHs contents and ring compositions were quite limited. The results can provide some evidences and data on the pollutant accumulation in drink water protection area influenced by natural processes and human activities.

  11. Variations of Heavy Metals from Geothermal Spring to Surrounding Soil and Mangifera Indica–Siloam Village, Limpopo Province

    Directory of Open Access Journals (Sweden)

    Olatunde S. Durowoju

    2016-01-01

    Full Text Available Assessment of seasonal variation in concentration of heavy metals–As, Cd, Co, Cr, Cu, Ni, Pb, and Zn from the Siloam Geothermal Spring and their impacts on surface soils and Mangifera indica were undertaken during winter and summer seasons in South Africa. This was done to determine the environmental pollution status of surface soils and Mangifera indica around the geothermal spring. The geothermal spring water, surface soil (0–15 cm and Mangifera indica (bark and leaves samples were collected during 2014 winter and summer seasons. Soil and Mangifera indica samples were treated and digested using microwave and block digestion methods, respectively. The heavy metal concentrations were determined with inductively coupled plasma-mass spectrometer (ICP-MS (Agilent 7700. The result from this study showed that levels of heavy metals were higher in summer compared to winter season for geothermal spring water, surface soil, and Mangifera indica (barks and leaves. In two-tailed tests (Mann–Whitney U-test, geothermal spring water alone showed significant differences (Z = −2.1035, p < 0.05, whereas the surface soil and barks and leaves of Mangifera indica showed no significant differences (Z = 0.053; 0; −0.524, p > 0.05 in both seasons. Some heavy metals concentrations were above the standard guidelines for drinking water and typical soil, making the soil contaminated. This is a cause for concern as it can affect the environment and the health of the inhabitants of Siloam village, who depend on the geothermal spring as their source of domestic water, irrigation, and other uses. This study also showed that Mangifera indica has a phytoremediative property, which lessens the heavy metal concentrations absorbed from the contaminated soil.

  12. Scattering of a CO2 laser beam at 10.6 microns by bare soils: Experimental study of the polarized bidirectional scattering coefficient - Model and comparison with directional emissivity measurements

    Science.gov (United States)

    Nerry, Francoise; Stoll, Marc P.; Kologo, Noaga

    1991-09-01

    The bistatic polarized scattering by bare soil samples of a CO2 laser beam at 10.6 microns has been experimentally studied. Large differences between HH and VV curves are usually observed, particularly in the forward plane. A simple phenomenological parameterization is proposed, based on the assumption of totally incoherent scattering by a rough medium. The normalized function F(theta)/F(0) accounting for slope distribution and shadowing is found from angular backscatter to be of the form cos super m(theta), with m = 5.24 for all samples. This result is generalized to account for the bistatic case. The index of refraction of the medium is obtained from the ratio of HH and VV curves in the forward plane. Good agreement is found between experimental and calculated curves in the case of sand. The directional reflectivity and emissivity are calculated and compare well with experimental data.

  13. The partitioning behavior of trace element and its distribution in the surrounding soil of a cement plant integrated utilization of hazardous wastes.

    Science.gov (United States)

    Yang, Zhenzhou; Chen, Yan; Sun, Yongqi; Liu, Lili; Zhang, Zuotai; Ge, Xinlei

    2016-07-01

    In the present study, the trace elements partitioning behavior during cement manufacture process were systemically investigated as well as their distribution behaviors in the soil surrounding a cement plant using hazardous waste as raw materials. In addition to the experimental analysis, the thermodynamic equilibrium calculations were simultaneously conducted. The results demonstrate that in the industrial-scale cement manufacture process, the trace elements can be classified into three groups according to their releasing behaviors. Hg is recognized as a highly volatile element, which almost totally partitions into the vapor phase. Co, Cu, Mn, V, and Cr are considered to be non-volatile elements, which are largely incorporated into the clinker. Meanwhile, Cd, Ba, As, Ni, Pb, and Zn can be classified into semi-volatile elements, as they are trapped into clinker to various degrees. Furthermore, the trace elements emitted into the flue gas can be adsorbed onto the fine particles, transport and deposit in the soil, and it is clarified here that the soil around the cement plant is moderately polluted by Cd, slightly polluted by As, Cr, Ba, Zn, yet rarely influenced by Co, Mn, Ni, Cu, Hg, and V elements. It was also estimated that the addition of wastes can efficiently reduce the consumption of raw materials and energy. The deciphered results can thus provide important insights for estimating the environmental impacts of the cement plant on its surroundings by utilizing wastes as raw materials.

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

    Energy Technology Data Exchange (ETDEWEB)

    Critto, Andrea; Carlon, Claudio; Marcomini, Antonio

    2003-04-01

    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{sub 4}{sup 2-} and Cl{sup -} 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.

  15. Soil data for a thermokarst bog and the surrounding permafrost plateau forest, located at Bonanza Creek Long Term Ecological Research Site, Interior Alaska

    Science.gov (United States)

    Manies, Kristen L.; Fuller, Christopher C.; Jones, Miriam C.; Waldrop, Mark P.; McGeehin, John P.

    2017-01-19

    Peatlands play an important role in boreal ecosystems, storing a large amount of soil organic carbon. In northern ecosystems, collapse-scar bogs (also known as thermokarst bogs) often form as the result of ground subsidence following permafrost thaw. To examine how ecosystem carbon balance changes with the loss of permafrost, we measured carbon and nitrogen storage within a thermokarst bog and the surrounding forest, which continues to have permafrost. These sites are a part of the Bonanza Creek Long Term Ecological Research (LTER) site and are located within Interior Alaska. Here, we report on methods used for core collection analysis as well as the cores’ physical, chemical, and descriptive properties.

  16. [Rare earth elements content in farmland soils and crops of the surrounding copper mining and smelting plant in Jiangxi province and evaluation of its ecological risk].

    Science.gov (United States)

    Jin, Shu-Lan; Huang, Yi-Zong; Wang, Fei; Xu, Feng; Wang, Xiao-Ling; Gao, Zhu; Hu, Ying; Qiao Min; Li, Jin; Xiang, Meng

    2015-03-01

    Rare earth elements content in farmland soils and crops of the surrounding copper mining and smelting plant in Jiangxi province was studied. The results showed that copper mining and smelting could increase the content of rare earth elements in soils and crops. Rare earth elements content in farmland soils of the surrounding Yinshan Lead Zinc Copper Mine and Guixi Smelting Plant varied from 112.42 to 397.02 mg x kg(-1) and 48.81 to 250.06 mg x kg(-1), and the average content was 254.84 mg x kg(-1) and 144.21 mg x kg(-1), respectively. The average contents of rare earth elements in soils in these two areas were 1.21 times and 0.68 times of the background value in Jiangxi province, 1.36 times and 0.77 times of the domestic background value, 3.59 times and 2.03 times of the control samples, respectively. Rare earth elements content in 10 crops of the surrounding Guixi Smelting Plant varied from 0.35 to 2.87 mg x kg(-1). The contents of rare earth elements in the leaves of crops were higher than those in stem and root. The contents of rare earth elements in Tomato, lettuce leaves and radish leaves were respectively 2.87 mg x kg(-1), 1.58 mg x kg(-1) and 0.80 mg x kg(-1), which were well above the hygienic standard limit of rare earth elements in vegetables and fruits (0.70 mg x kg(-1)). According to the health risk assessment method recommended by America Environmental Protection Bureau (USEPA), we found that the residents' lifelong average daily intake of rare earth elements was 17.72 mg x (kg x d)(-1), lower than the critical value of rare earth elements damage to human health. The results suggested that people must pay attention to the impact of rare earth elements on the surrounding environment when they mine and smelt copper ore in Jiangxi.

  17. Fate of hazardous elements in agricultural soils surrounding a coal power plant complex from Santa Catarina (Brazil).

    Science.gov (United States)

    Rodriguez-Iruretagoiena, Azibar; Fdez-Ortiz de Vallejuelo, Silvia; Gredilla, Ainara; Ramos, Claudete G; Oliveira, Marcos L S; Arana, Gorka; de Diego, Alberto; Madariaga, Juan Manuel; Silva, Luis F O

    2015-03-01

    Hazard element contamination coming from coal power plants is something obvious, but when this contamination is accompanied by other contamination sources, such as, urban, coal mining and farming activities the study gets complicated. This is the case of an area comprised in the southern part of Santa Catarina state (Brazil) with the largest private power plant generator. After the elemental analysis of 41 agricultural soils collected in an extensive area around the thermoelectric (from 0 to 47 km), the high presence of As, Co, Cr, Cu, Fe, Mn, Mo, Pb, Sb, Sn, Tl, V and Zn was found in some specific areas around the power plant. Nevertheless, as the NWAC (Normalized-and-Weighted Average Concentration) confirmed, only soils from one site were classified as of very high concern due to the presence of potential toxic elements. This site was located within the sedimentation basin of the power plant. The spatial distribution obtained by kriging in combination with the analysis of the data by Principal Component Analysis (PCA) revealed three important hotspots in the area according to soil uses and geographic localization: the thermoelectric, its area of influence due to volatile compound deposition, and the area comprised between two urban areas. Farming practice turn out to be an important factor too for the quantity of hazard element stored in soils.

  18. Use of a culture independent method to analyze the diversity of soil fungi surrounding Chroogomphus rutilus in the Beijing region of China

    DEFF Research Database (Denmark)

    Liu, Yu; Wang, Shouxian; Yin, Yonggang

    2012-01-01

    Large-scale cultivation of Chroogomphus rutilus is too inefficient to be commercially feasible. In addition, isolating C. rutilus mycelia in the wild is difficult. Thus, determining the natural habitat of its fruiting body is important. The present study focused on the ecology of the C. rutilus...... habitat to facilitate its large-scale cultivation. A culture-independent molecular approach—a powerful technology for microbiological ecology studies—was used to investigate the diversity of soil fungal communities in samples surrounding C. rutilus from the Beijing region of China. Metagenomic DNA...... was isolated from soil samples collected around C. rutilus, and an internal transcribed spacer (ITS) gene library was constructed. Subsequently, polymerase chain reaction products were digested with HinfI, HaeIII, MspI, TaqI, or MboI. Clones were selected and sequenced based on their restriction fragment...

  19. Levels and distribution of methoxylated and hydroxylated polybrominated diphenyl ethers in plant and soil samples surrounding a seafood processing factory and a seafood market.

    Science.gov (United States)

    Sun, Jianteng; Liu, Jiyan; Liu, Yanwei; Jiang, Guibin

    2013-05-01

    Polybrominated diphenyl ethers (PBDEs) along with hydroxylated polybrominated diphenyl ethers (OH-PBDEs) and methoxylated polybrominated diphenyl ethers (MeO-PBDEs) were found in plant and soil samples collected surrounding a seafood processing factory and a seafood market in China. The profiles of MeO-PBDE congeners were different between seafood processing factory and seafood market. The detection frequency and concentration of 6-OH-BDE-47 were lower than that of MeO-PBDEs. Near seafood processing factory, a decreasing trend of analyte concentrations in plants was found downstream the river where factory wastewater was discharged. Concentrations of ΣMeO-PBDEs in plant and soil samples showed difference as root > soil > leaf. However, at seafood market, the concentrations of ΣMeO-PBDEs were much higher in leaves than those in soil. The concentration of ΣMeO-PBDEs in leaves showed a remarkable difference between Calystegia soldanella (Linn.) R. Br. and Setaira viridis (L.) Beauv.

  20. Occurrence, sources, and potential human health risks of polycyclic aromatic hydrocarbons in agricultural soils of the coal production area surrounding Xinzhou, China.

    Science.gov (United States)

    Zhao, Long; Hou, Hong; Shangguan, Yuxian; Cheng, Bin; Xu, Yafei; Zhao, Ruifen; Zhang, Yigong; Hua, Xiaozan; Huo, Xiaolan; Zhao, Xiufeng

    2014-10-01

    A comprehensive investigation of the levels, distribution patterns, and sources of polycyclic aromatic hydrocarbons (PAHs) in agricultural soils of the coal production area surrounding Xinzhou, China, was conducted, and the potential human health risks associated with the levels observed were addressed. A total of 247 samples collected from agricultural soils from the area were analyzed for sixteen PAHs, including highly carcinogenic isomers. The PAH concentrations had a range of n.d. to 782ngg(-1), with a mean value of 202ngg(-1). The two-three ring PAHs were the dominant species, making up 60 percent of total PAHs. Compared with the pollution levels and carcinogenic potential risks reported in other studies, the soil PAH concentrations in the study area were in the low to intermediate range. A positive matrix factorization model indicates that coal/biomass combustion, coal and oil combustion, and coke ovens are the primary PAH sources, accounting for 33 percent, 26 percent, and 24 percent of total PAHs, respectively. The benzo[a]pyrene equivalent (BaPeq) concentrations had a range of n.d. to 476ngg(-1) for PAH7c, with a mean value of 34ngg(-1). The BaPeq concentrations of PAH7c accounted for more than 99 percent of the ∑PAH16, which suggests that seven PAHs were major carcinogenic contributors of ∑PAH16. According to the Canadian Soil Quality Guidelines, only six of the soil samples had concentrations above the safe BaPeq value of 600ngg(-1); the elevated concentrations observed at these sites can be attributed to coal combustion and industrial activities. Exposure to these soils through direct contact probably poses a significant risk to human health as a result of the carcinogenic effects of PAHs. Copyright © 2014 Elsevier Inc. All rights reserved.

  1. Accumulation of sulfur and heavy metals in soil and tree leaves sampled from the surroundings of Tuncbilek Thermal Power Plant.

    Science.gov (United States)

    Cicek, A; Koparal, A S

    2004-11-01

    In this study, the quantities of sulfur and heavy metals, resulting from the Tuncbilek Thermal Power Plant (TPP) in Turkey, have been assessed in tree leaves and soil samples within a 10 km radius of the plant. Leaves of Salix alba L., Populus tremula L., Robinia pseudoacacia L., Quercus infectoria L., Pinus nigra Arn. ssp. pallasiana (Lamb) Holmboe. trees have been used with the aim of determining how far the gas and particles emitted from the TPP are carried, and for assessment of environmental impact. The results obtained from locations chosen at various distances to the TPP, indicate that the contaminating agents are very dense and effective; particularly in the prevailing wind direction and within 10 km of the plant. They gradually lose their density and effect beyond this distance. The sulfur and heavy metal analyses made in soils taken from these locations indicate a similarity with the data obtained from the leaves.

  2. Multivariate spatial analyses of the distribution and origin of trace and major elements in soils surrounding a secondary lead smelter.

    Science.gov (United States)

    Schneider, Arnaud R; Morvan, Xavier; Saby, Nicolas P A; Cancès, Benjamin; Ponthieu, Marie; Gommeaux, Maxime; Marin, Béatrice

    2016-08-01

    Major and trace elements in soils originate from natural processes and different anthropogenic activities which are difficult to discriminate. On a 17-ha impacted site in northern France, two industrial sources of soil contamination were xidentified: a former iron foundry and a current secondary lead smelter. To discriminate and map natural and anthropogenic sources of major and trace elements on this site, the rarely applied MULTISPATI-principal component analysis (PCA) method was used. Using a 20-m × 20-m grid, 247 topsoil horizons were sampled and analysed with a field-portable X-ray fluorescence analyser for screening soil contamination. The study site was heavily contaminated with Pb and, to a lesser degree, with Sn. Summary statistics and enrichment factors allowed the differentiation of the main lithogenic or anthropogenic origin of the elements. The MULTISPATI-PCA method, which explained 73.9 % of the variability with the three first factors, evidenced strong spatial structures. Those spatial structures were attributed to different natural and artificial processes in the study area. The first axis can be interpreted as a lithogenic effect. Axes 2 and 3 reflect the two different contamination sources. Pb, Sn and S originated from the secondary lead smelter while Fe and Ca were mainly derived from the old iron foundry activity and the old railway built with foundry sand. This study demonstrated that the MULTISPATI-PCA method can be successfully used to investigate multicontaminated sites to discriminate the various sources of contamination.

  3. Releases of phosphate fertilizer industry in the surrounding environment: investigation on heavy metals and polonium-210 in soil.

    Science.gov (United States)

    Aoun, M; El Samrani, A G; Lartiges, B S; Kazpard, V; Saad, Z

    2010-01-01

    Distribution of Cu, Zn, Pb, Cr, Ni, Mn concentrations and the activity of polonium-210 in the surrounding area of a phosphate fertilizer industry located on the eastern coast of the Mediterranean Sea has been determined. Nineteen sampling sites were distributed around the industrial zone on a surface area of about 100,000 m2. Atomic absorption spectroscopy and Alpha spectroscopy were used to quantify the heavy elements and polonium-210, respectively. Investigation on a particle scale was conducted by TEM and SEM coupled to EDX and X-ray cartography to determine the nature of heavy elements carriers and their distribution. Heavy elements were mainly concentrated inside the particle size fraction Polonium-210 with an enrichment factor of about 56, showed the same behavior of the spatial distribution of the trace elements.

  4. The Globe laid bare

    CERN Multimedia

    Anaïs Schaeffer

    2015-01-01

    If you’re at CERN at the moment, you will certainly have noticed the work under way on the Globe. The structure, which has been in pride of place opposite the Laboratory for over ten years, has never been so completely laid bare. But, as we explained in a previous article (see here), it is all for a good cause. The Globe is built entirely from wood and certain parts of it need to be replaced.   The Globe after the removal of all the sun baffles. Image: Lucien Fortunati. Picture the general structure of the Globe. In simple terms, the building consists of two spheres, one inside the other. The inner sphere houses the Universe of Particles exhibition and the conference room and is connected to the outer sphere by two access ramps. “Each of these two spheres is made up of eighteen large supporting arcs,” explains Amaya Martínez García of the GS department, who is supervising the Globe renovation project. “These eighteen arcs are ...

  5. Landslide susceptibility assessment in ash-fall pyroclastic deposits surrounding Mount Somma-Vesuvius: Application of geophysical surveys for soil thickness mapping

    Science.gov (United States)

    De Vita, P.; Agrello, D.; Ambrosino, F.

    2006-06-01

    Along the steep slopes of the carbonate mountains that surround the Campanian Plain and Mount Somma-Vesuvius, rainfall-triggered debris slides occur in unconsolidated ash-fall pyroclastic deposits. The initial debris slides evolve into debris flows that often cause significant property damage and loss of human life in the towns located at the foot of the slopes. In this particular geological situation, the pyroclastic soil thickness, the slope angle, and the morphological variations of the slope profile are the most important factors that contribute to landslide susceptibility. In this paper, the results of an experimental application of shallow resistivity and refraction seismic soundings in mapping the thickness of pyroclastic soils are presented. These geophysical methods are proposed as low-cost and versatile methods to be used in the difficult morphological conditions of the steep slopes in which debris-slides initiate. The methods have been used experimentally in a sample area located on the upper slope of Mount Pizzo d'Alvano, from which debris flows initiated that dramatically hit the town of Sarno on 5-6 May 1998. The inversion of geoelectrical soundings has been calibrated with resistivity values measured directly on pyroclastic outcrops and with soil thickness estimations derived from refraction seismic soundings and from the application of a mobile dynamic penetrometer. The results of the field experimentation can be summarised as follows: (i) unconsolidated ash-fall pyroclastic deposits, ranging in particle size from fine ash to lapilli, can be differentiated from fractured carbonate bedrock by means of electrical resistivity and velocity values of longitudinal seismic waves; (ii) thickness of ash-fall pyroclastic soils can be empirically related to the slope angle using an inverse relationship; and (iii) the empirical model has been applied to Digital Elevation Model data, allowing pyroclastic soil thickness mapping in the sample area.

  6. Long-term assessment of airborne radiocesium after the Fukushima nuclear accident. Re-suspension from bare soil and forest ecosystems

    Energy Technology Data Exchange (ETDEWEB)

    Kajino, Mizuo [Japan Meteorological Agency (JMA), Ibaraki (Japan). Meteorological Research Inst. (MRI); RIKEN Advanced Institute for Computational Science (AICS), Hyogo (Japan); Ishizuka, Masahide [Kagawa Univ. (Japan). Faculty of Engineering; Igarashi, Yasuhito [Japan Meteorological Agency (JMA), Ibaraki (Japan). Meteorological Research Inst. (MRI); Kita, Kazuyuki [Ibaraki Univ. (Japan). Faculty of Science; Yoshikawa, Chisato [Japan Agency for Marine-Earth Science and Technology (JAMSTEC), Kanagawa (Japan); Inatsu, Masaru [Hokkaido Univ., Sapporo (Japan). Faculty of Science

    2016-07-01

    The long-term effect of {sup 137}Cs re-suspension from contaminated soil and forests due to the Fukushima nuclear accident has been quantitatively assessed by numerical simulation, a field experiment on dust emission flux in a contaminated area (town of Namie, Fukushima prefecture), and air concentration measurements inside (Namie) and outside (city of Tsukuba, Ibaraki prefecture) the contaminated area. In order to assess the long-term effect, the full year of 2013 was selected to study just after the start of the field experiments. The {sup 137}Cs concentrations at Namie and Tsukuba were approximately 10{sup -1}-1 and 10{sup -2}-10{sup -1} mBq m{sup -3}, respectively. The observed monthly median concentration at Namie was 1 to 2 orders of magnitude larger than that at Tsukuba. This observed difference between the two sites was consistent with the simulated difference, indicating successful modeling of {sup 137}Cs re-suspension and atmospheric transport. The estimated re-suspension rate was approximately 10{sup -6} day{sup -1}, which was significantly lower than the decreasing rate of the ambient gamma dose rate in Fukushima prefecture (10{sup -4}-10{sup -3} day{sup -1}) as a result of radioactive decay, migration in the soil and biota, and decontamination. Consequently, re-suspension contributed negligibly in reducing ground radioactivity. The dust emission model could reproduce the air concentration of {sup 137}Cs in winter, whereas the summer air concentration was underestimated by 1 to 2 orders of magnitude. Re-suspension from forests at a constant rate of 10{sup -7} h{sup -1}, multiplied by the green area fraction, could explain the air concentration of {sup 137}Cs at Namie and its seasonal variation. The simulated contribution of dust re-suspension to the air concentration was 0.7-0.9 in the cold season and 0.2-0.4 in the warm season at both sites; the remainder of the contribution was re-suspension from forest. The re-suspension mechanisms, especially

  7. Long-term assessment of airborne radiocesium after the Fukushima nuclear accident: re-suspension from bare soil and forest ecosystems

    Science.gov (United States)

    Kajino, Mizuo; Ishizuka, Masahide; Igarashi, Yasuhito; Kita, Kazuyuki; Yoshikawa, Chisato; Inatsu, Masaru

    2016-10-01

    The long-term effect of 137Cs re-suspension from contaminated soil and forests due to the Fukushima nuclear accident has been quantitatively assessed by numerical simulation, a field experiment on dust emission flux in a contaminated area (town of Namie, Fukushima prefecture), and air concentration measurements inside (Namie) and outside (city of Tsukuba, Ibaraki prefecture) the contaminated area. In order to assess the long-term effect, the full year of 2013 was selected to study just after the start of the field experiments. The 137Cs concentrations at Namie and Tsukuba were approximately 10-1-1 and 10-2-10-1 mBq m-3, respectively. The observed monthly median concentration at Namie was 1 to 2 orders of magnitude larger than that at Tsukuba. This observed difference between the two sites was consistent with the simulated difference, indicating successful modeling of 137Cs re-suspension and atmospheric transport. The estimated re-suspension rate was approximately 10-6 day-1, which was significantly lower than the decreasing rate of the ambient gamma dose rate in Fukushima prefecture (10-4-10-3 day-1) as a result of radioactive decay, migration in the soil and biota, and decontamination. Consequently, re-suspension contributed negligibly in reducing ground radioactivity. The dust emission model could reproduce the air concentration of 137Cs in winter, whereas the summer air concentration was underestimated by 1 to 2 orders of magnitude. Re-suspension from forests at a constant rate of 10-7 h-1, multiplied by the green area fraction, could explain the air concentration of 137Cs at Namie and its seasonal variation. The simulated contribution of dust re-suspension to the air concentration was 0.7-0.9 in the cold season and 0.2-0.4 in the warm season at both sites; the remainder of the contribution was re-suspension from forest. The re-suspension mechanisms, especially through the forest ecosystems, remain unknown. This is the first study that provides a crude

  8. Comparation of the Uptake and Accumulation of Heavy Metals by Rape Species Grown in Contaminated Soil Surrounding Mining Tails in Chenzhou, China

    Directory of Open Access Journals (Sweden)

    YANG Yang

    2015-08-01

    Full Text Available The rape is usually used for phytoremediation of metal-contaminated soils, because it has the characteristics of rapid growth, large biomass, and high potential to tolerate and accumulate large quantities of heavy metals. In this work, accumulation and transformation of Cu, Zn, Pb, Cd in four rape species(B. juncea L.(BJ, Brassica napus L.(BL, Canadian Brassica napus L.(CBL, local rape(LRwere investigated in soils surrounding mine area contaminated by lead-zinc ore tailings in Chenzhou, Hunan Province. The results showed a significantly high accumulation of Cu, Zn and Cd in leaves and roots of four rape species. However, the concentration of Pb in roots of all rape species was usually one or two orders of magnitude than other parts, and the concentration of heavy metals in stems and fruits was lower. The accumulation of heavy metals in leaves parts was in the order: Zn >Cu >Pb >Cd, and in roots was as: Pb >Zn >Cu >Cd; the order of bioconcentration factor(BCFof heavy metals in above-ground parts(leavesof rape species was: Cu: BJ ≥LR >BL >CBL, Zn: BL >CBL >BJ >LR, Pb: BJ≈LR > BL≈CBL, Cd: BL >CBL >BJ >LR; and the order of translocation factor(TFfrom stems to leaves was: Cu: LR >BJ≈CBL >BL,Zn: BL >LR > BJ >CBL, Pb: BJ >CBL≈LR >BL,Cd: BJ >BL >CBL >LR. It indicated there were significant differences among the species. The results of the field experiment suggested that B. juncea L. was suitable for phytoextraction of Cu, Pb contaminated soil, Brassica napus L. could be used to remediate Zn, Cd or heavy metal combined polluted soils.

  9. Scattering of a CO(2) laser beam at 10.6 microm by bare soils: experimental study of the polarized bidirectional scattering coefficient; model and comparison with directional emissivity measurements.

    Science.gov (United States)

    Nerry, F; Stoll, M P; Kologo, N

    1991-09-20

    The bistatic polarized scattering by bare soil samples of a CO(2) laser beam at 10.6 microm has been experimentally studied. Large differences between HH and VV curves are usually observed, particularly in the forward plane. A simple phenomenological parameterization is proposed, based on the assumption of totally incoherent scattering by a rough medium. The normalized function F(theta)/F(0) accounting for slope distribution and shadowing is found from angular backscatter to be of the form cos(m)(theta), with m = 5.24 for all samples. This result is generalized to account for the bistatic case. The index of refraction of the medium is obtained from the ratio of HH and VV curves in the forward plane. Good agreement is found between experimental and calculated curves in the case of sand. The directional reflectivity and emissivity are calculated and compare well with experimental data. The calculated emissivity at nadir, for lambda = 10.6 microm, is within 0.5% of the value directly measured from emitted radiation. The backscattered peak has not yet been addressed in detail, therefore preventing relating in a semiquantitative manner the intensity of the backscattered light and the emissivity.

  10. Solid Bare Strange Quark Stars

    CERN Document Server

    Xu, R X

    2003-01-01

    The reason, we need three terms of `strange', `bare', and `solid' before quark stars, is presented concisely though some fundamental issues are not certain. Observations favoring these stars are introduced.

  11. Validation of numeric methods for calculating interactions between district heating pipelines and the surrounding soil; Validierung numerischer Verfahren zur Berechnung des Interaktionsverhaltens 'Fernwaermeleitung - Baugrund'

    Energy Technology Data Exchange (ETDEWEB)

    Salveter, G.

    2000-07-01

    In this thesis, the results of experimental research work on global bearing behaviour with respect to the existing theoretical basis are systematically analysed for the evaluation and interpretation of measuring results. Among other things, the geometry of the pipeline route, the compactness of the backfilling material and the temperature dependence are considered. The mutual influence of friction and bedding resistances in the region of bends could not yet be determined for a local analysis by existing numerical models. This requires the determination of the induced stress distribution on the pipe perimeter due to lateral displacement of the pipe. The influence is therefore described by a numerical consideration of relative displacements between the pipe and the surrounding soil. Ultimately, relative displacements are verified on the basis of our own complementary results from experimental research carried out in a laboratory for soil mechanics with specially designed test equipment. The global analysis of bearing loads and displacements is done with a numerical model, in which the plastic jacked pipe is idealized as a beam, and the effect of the soil is idealized by spring elements with non-linear force displacement characteristics. An existing numerical model is extended with regard to the new findings and while taking vertical displacements into account. It is used for numerical simulations of selected tests on the global bearing behaviour of underground district heating pipelines which were carried out as part of the research cooperation project. Apart from a good correspondence between calculated results and test results this also provides a plausible description of interrelations. At the same time, however, it also makes itclear that further research is necessary. This thesis provides a contribution to the validation of recent methods for the calculated modelling of the interaction between a district heating pipeline and the subsoil on the basis of

  12. 基于可见光-短波红外波谱反射率的裸土土壤含水量反演建模%Bare Soil Moisture Inversion Model Based on Visible-Shortwave Infrared Reflectance

    Institute of Scientific and Technical Information of China (English)

    郑小坡; 孙越君; 秦其明; 任华忠; 高中灵; 吴伶; 孟庆野; 王金梁; 王建华

    2015-01-01

    artificially prepared ,and soil reflectance spectra was consequently measured using spectroradiometer produced by ASD Company .Secondly ,the moisture ab‐sorption spectral feature located at shortwave wavelengths and the spectral slope of visible wavelengths were calculated after ana‐lyzing the regular spectral feature change patterns of different soil at different moisture conditions .Then advantages of the two features at reducing soil types’ effects was synthesized to build the NSSAI .Thirdly ,a linear relationship between NSSAI and soil moisture was established .The result showed that NSSAI worked better (correlation coefficient is 0 .93) than most of other traditional methods in soil moisture extraction .It can weaken the influences caused by soil types at different moisture levels and improve the bare soil moisture inversion accuracy .

  13. Acquisition of Structure and Interpretation: Cases from Mandarin Bare and Non-Bare Noun Phrases

    Science.gov (United States)

    Chang, Hsiang-Hua

    2011-01-01

    Children's production of bare nominals is universal. When acquiring languages disallowing bare nominals, children will develop from the bare to the non-bare stage. However, Mandarin nominals may appear bare or non-bare in various positions with all kinds of interpretations. This dissertation conducts two acquisition studies to examine the…

  14. Metal concentrations in the soils and native plants surrounding the old flotation tailings pond of the copper mining and smelting complex Bor (Serbia).

    Science.gov (United States)

    Antonijević, M M; Dimitrijević, M D; Milić, S M; Nujkić, M M

    2012-03-01

    In this study concentrations of metals in the native plants and soils surrounding the old flotation tailings pond of the copper mine were determined. It has been established that the soil is heavily contaminated with copper, iron and arsenic, the mean concentrations being 1585.6, 29,462.5 and 171.7 mg kg(-1) respectively. All the plants, except manganese, accumulated metallic elements in concentrations which were either in the range of critical and phytotoxic values (Pb and As) or higher (Zn), and even much higher (Cu and Fe) than these values. Otherwise, the accumulation of Mn, Pb and As was considerably lower than that of Cu, Fe and Zn. In most plants the accumulation of target metals was highest in the root. Several plant species showed high bioaccumulation and translocation factor values, which classify them into species for potential use in phytoextraction. The BCF and TF values determined in Prunus persica were 1.20 and 3.95 for Cu, 1.5 and 6.0 for Zn and 1.96 and 5.44 for Pb. In Saponaria officinalis these values were 2.53 and 1.27 for Zn, and in Juglans regia L. they were 8.76 and 17.75 for Zn. The translocation factor in most plants, for most metals, was higher than one, whereas the highest value was determined in Populus nigra for Zn, amounting to 17.8. Among several tolerant species, the most suitable ones for phytostabilization proved to be Robinia pseudoacacia L. for Zn and Verbascum phlomoides L., Saponaria officinalis and Centaurea jacea L. for Mn, Pb and As. This journal is © The Royal Society of Chemistry 2012

  15. Taxa de emissão de CO2 de um latossolo fertirrigado com ácido fosfórico por gotejamento CO2 emission rate from a fertigated bare soil with phosphoric acid by dripping

    Directory of Open Access Journals (Sweden)

    José R. Zanini

    2005-04-01

    Full Text Available A aplicação de fertilizantes fosfatados por meio de fertirrigação com sistemas de irrigação localizada pode causar obstrução de emissores. Para evitar esse problema, pode ser utilizado o ácido fosfórico como fonte de fósforo às plantas. Porém, têm sido pouco investigados os efeitos da irrigação relacionados às perdas de CO2 do solo para a atmosfera, em conseqüência da decomposição do carbono orgânico e da infiltração de água no solo. Neste trabalho, investigou-se, no período de um mês, o efeito da fertirrigação com ácido fosfórico nas taxas de emissão de CO2 de um latossolo desprovido de vegetação, na Área Experimental de Irrigação da UNESP, Câmpus de Jaboticabal - SP. Utilizou-se de um sistema de irrigação por gotejamento, com delineamento experimental em blocos casualizados, constando de cinco repetições e cinco tratamentos (0; 30; 60; 90 e 120 kg ha-1de P2O5, aplicados via fertirrigação com ácido fosfórico. Verificou-se que as taxas de emissão de CO2 aumentaram significativamente após as fertirrigações, porém não houve efeito da dose do ácido fosfórico sobre as taxas. A umidade do solo mostrou-se um fator importante na relação entre as variações das taxas de emissão e a temperatura do solo ao longo do período estudado.The application of phosphoric fertilizers through fertigation, with localized irrigation systems, can cause emitters obstruction. In order to avoid this problem, the phosphoric acid can be used as phosphorus source to the plants. However, it has been little investigations on the effects of the irrigation practices, related to the CO2 transference to the atmosphere, due to organic matter decomposition in the soil and its water infiltration. At this work, the rates of emissions of CO2 from a bare soil without vegetation, and fertigated along one month were investigated. The experiment was conducted with randomized blocks design in São Paulo State University - UNESP

  16. Emission of SO2 and SO42- from copper smelter and its influence on the level of total s in soil and moss in Bor and the surroundings

    Directory of Open Access Journals (Sweden)

    Šerbula Snežana M.

    2015-01-01

    Full Text Available Bor and the surroundings (Eastern Serbia have been known for exploitation and processing of sulphide copper ores for more than 100 years. Emissions of waste gases and particulate matter rich in heavy metals are characteristic for pyrometallurgical production of copper. Long-term measurement results (2005-2008 indicate an increased sulphur dioxide level in the urban-industrial zone of Bor since it is closest to the copper smelter which is a dominant source of air pollution in the studied area. Average annual sulphur dioxide concentrations at four measuring sites in the urban-industrial zone exceeded the maximum allowable value of 50 μg/m3. However the maximum allowable value of the total atmospheric depositions (200 mg/m2/day on an annual basis exceeded only at two of 15 measuring sites in the urban-industrial and rural zone. The highest annual deposition rate of sulphates from deposition was detected in the urban-industrial zone. Since the maximum permitted value for sulphates is not defined by the Serbian Regulations, the extent of the pollution cannot be discussed. Since the environment can continuously be polluted through the wet and dry deposition, biomonitoring by moss was conducted, which revealed significantly higher concentrations of total sulphur in moss in the urban-industrial zone, compared to the background zone. The obtained results confirm the reliability of moss as a bioindicator of ambient pollution. Higher total S concentration in soil samples was noted at the rural site (Ostrelj located in the close vicinity of two tailing ponds. [Projekat Ministarstva nauke Republike Srbije, br. 46010, br. 33038 i br. 172037

  17. Planting Rice on the Surrounding Dry Land Soil Salinity and Soil Moisture Content Influence the Research%种稻对周围旱地土壤盐分和土壤水分含量的影响

    Institute of Scientific and Technical Information of China (English)

    田生昌; 陈新会; 马建军; 田慧萍; 冒海军

    2012-01-01

    为了研究种稻对周围旱地影响的程度和范围,选择稻旱田之间无沟和有沟相隔型两种类型,以不受种稻影响的老旱田作对照,在距稻田50.、80、150和200 m处各埋设定位观测井,监测种稻对地下水埋深、土壤水分含量和土壤盐分含量的影响.结果表明,耕层土壤水分含量与地下水埋深相关极显著,耕层土壤盐分含量与地下水埋深相关极显著,在上升期,旱田距稻田距离与地下水埋深相关极显著.因此,稻旱田之间无沟相隔时,种稻对周围旱地的影响表现为稻田水直接向旱田侧渗,而使距稻田附近旱田的地下水位上升,在距稻田220.7 m内地下水位会上升到危害旱作物生长的程度;稻旱田之间有沟相隔时,种稻会导致稻旱田之间排水沟水位上升,从而对周围旱田产生不利影响,这种影响即可通过沟水向旱田的侧渗发生,又表现在阻止旱田的排水上,其不利影响范围在200 m以内.%In order to study the impact of rice growing on surrounding dry land, we choose two types of rice fields, non-ditch separated, ditch separated and dry land as the control to monitor the ground-water depth, soil moisture and soil salt content at different distances (50, 80, 150 and 200 m) away from the rice fields by observation wells. The results showed that: topsoil moisture content was significantly related to groundwater depth. Topsoil soil salt content was significantly related to groundw-ater depth. In the rising period the distances away from the rice fields was significantly associated with groundwater depth. In conclusion, for the dry land and the non-ditch separated rice field, the lateral water seepage from rice field to dry land can increase the ground water level of dry land and in the distance away from the rice fields of 220. 7 m it can cause damage to the growth of dry land crops; for the dry land and ditch separated rice field, it will lead to the ditch water level rising, which

  18. Radioactivity measurements in soils surrounding four coal-fired power plants in Serbia by gamma-ray spectrometry and estimated dose

    Directory of Open Access Journals (Sweden)

    Vukašinović Ivana Ž.

    2014-01-01

    Full Text Available The study of spatial distribution of activity concentration of 238U, 226Ra, 210Pb, 232Th, 40K, and 137Cs radionuclides in the surface soil samples (n = 42 collected in the vicinity of four coal-fired power plants in Serbia is presented. Radioactivity measurements in soils performed by gamma-ray spectrometry showed values [Bqkg-1] in the range: 15-117 for 238U, 21-115 for 226Ra, 33-65 for 210Pb, 20-69 for 232Th, 324-736 for 40K, and 2-59 for 137Cs. Surface soil radio-activity that could have resulted from deposition of radionuclides from airborne discharges or resuspension of ash from disposal sites showed no enhanced levels. It was found that variation of soil textural properties, pH values, and carbonate content influenced activity levels of natural radionuclides while radiocesium activities were associated with soil organic matter content. Modification of some soil properties was observed in the immediate vicinity (<1 km of power plants where the soil was more alkaline with coarser particles (0.2-0.05 mm and carbonates accumulated. Calculated average values of the absorbed gamma dose rate and annual external effective dose originating from the terrestrial radionuclides were 69.4 nGy/h and 0.085 mSv, respectively. [Projekat Ministarstva nauke Republike Srbije, br. 4007: Studying climate change and its influence on the environment: impacts, adaptation and mitigation

  19. Climatic controls on carbon storage in seasonally frozen soils

    Science.gov (United States)

    Schultz, Colin

    2013-05-01

    When soil goes through an annual freeze-thaw cycle, the expansion and shrinkage of underground water causes a second cycle, one of heaving and sinking, that can produce unusual geometric patterns on the surface. Known as cryoturbation, this process drives buried boulders to the surface and lets fine particles settle in the holes left behind. In some regions, cryoturbation gives rise to circles on the surface (some a few meters wide): patches of bare soil ringed by rocks. In others, such as a site in northern Sweden analyzed by Becher et al., cryoturbation creates nonsorted circles: bare soil surrounded by trees or shrubs. The churning soil is inhospitable for the plants' roots, and if anything, only a light dusting of moss or lichen covers the centers of the circles.

  20. Activity and population dynamics of heterotrophic and ammonia-oxidizing microorganisms in soil surrounding sludge bands spiked with linear alkylbenzene sulfonate

    DEFF Research Database (Denmark)

    Brandt, K. K.; Sørensen, J.; Krogh, P. H.

    2003-01-01

    bioluminescence toxicity assay, however, LAS or other sludge components never accumulated to toxic levels in the soil compartments and the LAS tolerance of the indigenous microbes further remained unchanged following LAS exposure. LAS effects on the investigated microbial populations largely occurred during...

  1. Matrix methods for bare resonator eigenvalue analysis.

    Science.gov (United States)

    Latham, W P; Dente, G C

    1980-05-15

    Bare resonator eigenvalues have traditionally been calculated using Fox and Li iterative techniques or the Prony method presented by Siegman and Miller. A theoretical framework for bare resonator eigenvalue analysis is presented. Several new methods are given and compared with the Prony method.

  2. Bare strange quark stars formation and emission

    CERN Document Server

    Xu, R X

    2002-01-01

    Recent achievements of bare strange stars are briefly reviewed. A nascent protostrange star should be bare because of strong mass ejection and high temperature after the supernova detonation flame, and a crust can also hardly form except for a super-Eddington accretion. The magnetosphere of a bare strange star is composed mainly of electron-positron pair plasma, where both inner and outer vacuum gaps work for radio as well as high energy nonthermal emission. A featureless thermal spectrum is expected since no ion is above the quark surface, whilst electron cyclotron lines could appear in some bare strange stars with suitable magnetic fields. Various astrophysical implications of bare strange stars are discussed.

  3. Geochemistry of natural radionuclide in soils surrounding a mining and plant uranium concentration;Geoquimica de radionuclindeos naturais em solos de areas circunvizinhas a uma unidade de mineracao e atividade de uranio

    Energy Technology Data Exchange (ETDEWEB)

    Cardoso, Gildevan Viana, E-mail: gildevan.cardoso@vta.incra.gov.b [Instituto Nacional de Colonizacao e Reforma Agraria (INCRA), Rio de Janeiro, RJ (Brazil); Amaral Sobrinho, Nelson Moura Brasil do; Mazur, Nelson, E-mail: nelmoura@ufrrj.b, E-mail: nelmazur@ufrrj.b [Universidade Federal Rural do Rio de Janeiro (UFRRJ), Seropedica, RJ (Brazil). Inst. de Agronomia. Dept. de Solos; Wasserman, Maria Angelica Vergara, E-mail: angelica@ird.gov.b [Instituto de Radioprotecao e Dosimetria (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil)

    2009-11-15

    The environmental impacts resulting from uranium exploration and processing are to a great extent identical to those caused by extractive mining activities in general. This study aimed to determine the geochemical partitioning of the natural radionuclides {sup 238}U, {sup 226}Ra and {sup 210}Pb in areas surrounding the Uranium Mining and Concentration Plant (URA) of the Brazilian Nuclear Industries S.A., in the uranium deposit region of Lagoa Real, in Caetite, southwestern Bahia state. Representative soil samples of the main regional soil classes were collected from the layer 0-20 cm, in five areas around the URA. The level of total activity and geochemical fractionation (F1 slightly acidic, F2 reducible, F3 oxidisable, F4 alkaline, and F5 residual) were determined for the five areas. The average total radioactivity levels were, in Bq kg{sup -1} soil: 50 for {sup 238}U, 51 for {sup 226}Ra, and 159 for {sup 210}Pb. During the potentially bioavailable phase (F1) 11 % were extracted for {sup 238}U, 13 % for {sup 226}Ra and 3 % for {sup 210}Pb. The bioavailability of {sup 238}U was higher in more acidic soils and the affinity for iron oxides was greater, unlike in the case of {sup 226}Ra, with the greatest bioavailability. {sup 210}Pb was predominantly associated with F5. The high percentage of {sup 238}U, {sup 226}Ra and {sup 210}Pb in the geochemical fraction F5 indicates that the concentrations observed in the five soils are predominantly associated to the parent material of these soils, rather than to an artificial contamination caused by the URA activity. (author)

  4. The assessment of source attribution of soil pollution in a typical e-waste recycling town and its surrounding regions using the combined organic and inorganic dataset.

    Science.gov (United States)

    Luo, Jie; Qi, Shihua; Xie, Xianming; Gu, X W Sophie; Wang, Jinji

    2017-01-01

    Guiyu is a well-known electronic waste dismantling and recycling town in south China. Concentrations and distribution of the 21 mineral elements and 16 polycyclic aromatic hydrocarbons (PAHs) collected there were evaluated. Principal component analyses (PCA) applied to the data matrix of PAHs in the soil extracted three major factors explaining 85.7% of the total variability identified as traffic emission, coal combustion, and an unidentified source. By using metallic or metalloid element concentrations as variables, five principal components (PCs) were identified and accounted for 70.4% of the information included in the initial data matrix, which can be denoted as e-waste dismantling-related contamination, two different geological origins, anthropogenic influenced source, and marine aerosols. Combining the 21 metallic and metalloid element datasets with the 16 PAH concentrations can narrow down the coarse source and decrease the unidentified contribution to soil in the present study and therefore effectively assists the source identification process.

  5. Natural radioactivity levels in soils, rocks and water at a mining concession of Perseus gold mine and surrounding towns in Central Region of Ghana.

    Science.gov (United States)

    Faanu, A; Adukpo, O K; Tettey-Larbi, L; Lawluvi, H; Kpeglo, D O; Darko, E O; Emi-Reynolds, G; Awudu, R A; Kansaana, C; Amoah, P A; Efa, A O; Ibrahim, A D; Agyeman, B; Kpodzro, R; Agyeman, L

    2016-01-01

    Levels of naturally occurring radioactive materials prior to processing of gold ore within and around the new eastern concession area of Perseus Mining (Ghana) Limited were carried out to ascertain the baseline radioactivity levels. The study was based on situ measurements of external gamma dose rate at 1 m above ground level as well as laboratory analysis by direct gamma spectrometry to quantify the radionuclides of interest namely; (238)U, (232)Th and (40)K in soil, rock, ore samples and gross alpha/beta analysis in water samples. The average absorbed dose rate in air at 1 m above sampling point using a radiation survey metre was determined to be 0.08 ± 0.02 μGyh(-1) with a corresponding average annual effective dose calculated to be 0.093 ± 0.028 mSv. The average activity concentrations of (238)U, (232)Th, and (40)K in the soil, rock, and ore samples were 65.1 ± 2.2, 71.8 ± 2.2 and 1168.3 Bqkg(-1) respectively resulting in an average annual effective dose of 0.91 ± 0.32 mSv. The average Radium equivalent activity value was 257.8 ± 62.4 Bqkg(-1) in the range of 136.6-340.2 Bqkg(-1). The average values of external and internal indices were 0.7 ± 0.2 and 0.9 ± 0.2 respectively. The average gross alpha and gross beta activity concentrations in the water samples were determined to be 0.0032 ± 0.0024 and 0.0338 ± 0.0083 Bql(-1) respectively. The total annual effective dose from the pathways considered for this study (gamma ray from the soil, rock and ore samples as well as doses determined from the gross alpha/beta activity concentration in water samples) was calculated to be 0.918 mSv. The results obtained in this study shows that the radiation levels are within the natural background radiation levels found in literature and compare well with similar studies for other countries and the total annual effective dose is below the ICRP recommended level of 1 mSv for public exposure control.

  6. Assessment of the impact of an old MSWI. Part 1. Level of PCDD/Fs and PCBs in surrounding soils and eggs

    Energy Technology Data Exchange (ETDEWEB)

    Pirard, C.; Focant, J.F.; Massart, A.C.; Pauw, E. De [Mass Spectrometry Lab., Univ. of Liege (Belgium)

    2004-09-15

    This paper reports dioxin and PCB concentrations in soils and chicken eggs collected near an old municipal solid waste incinerator (MSWI). The specimens were collected in 11 homes from Maincy (France), a rural area located 60km south of Paris and 5km from Melun, a 40000 inhabitants industrial city. Less than 2km away from Maincy stands the Vaux-le-Penil MSWI. It began to operate in 1974 and was closed in June 2002 following a dioxin measures campaign of atmospheric emission. The facility with a capacity of 4 t/h, handled approximately 40000 tons of domestic waste per year, without any specific dioxin removal. Measured dioxin level was 226 ngTEQ/Nm{sup 3}, more than 2000 fold higher than the actual European norm of 0.1ngTEQ/Nm{sup 3}.

  7. Sub-soil contamination due to oil spills in zones surrounding oil pipeline-pump stations and oil pipeline right-of-ways in Southwest-Mexico.

    Science.gov (United States)

    Iturbe, Rosario; Flores, Carlos; Castro, Alejandrina; Torres, Luis G

    2007-10-01

    Oil spills due to oil pipelines is a very frequent problem in Mexico. Petroleos Mexicanos (PEMEX), very concerned with the environmental agenda, has been developing inspection and correction plans for zones around oil pipelines pumping stations and pipeline right-of-way. These stations are located at regular intervals of kilometres along the pipelines. In this study, two sections of an oil pipeline and two pipeline pumping stations zones are characterized in terms of the presence of Total Petroleum Hydrocarbons (TPHs) and Polycyclic Aromatic Hydrocarbons (PAHs). The study comprehends sampling of the areas, delimitation of contamination in the vertical and horizontal extension, analysis of the sampled soils regarding TPHs content and, in some cases, the 16 PAHs considered as priority by USEPA, calculation of areas and volumes contaminated (according to Mexican legislation, specifically NOM-EM-138-ECOL-2002) and, finally, a proposal for the best remediation techniques suitable for the contamination levels and the localization of contaminants.

  8. Genetics Home Reference: bare lymphocyte syndrome type I

    Science.gov (United States)

    ... Home Health Conditions bare lymphocyte syndrome type I bare lymphocyte syndrome type I Enable Javascript to view ... boxes. Download PDF Open All Close All Description Bare lymphocyte syndrome type I (BLS I) is an ...

  9. Notes on dematiaceous hyphomycetes from soil in Mount Taibai and its surrounding area Ⅱ%太白山及其周围地区土壤中的暗色丝孢菌Ⅱ

    Institute of Scientific and Technical Information of China (English)

    于金凤; 宋伟; 吴悦明; 张天宇

    2008-01-01

    In this sequel of report on soil dernatiaceous hyphomycetes from Mount Taibai and its surrounding area,18 species in 10 additional genera are included.The fungi were identified from 96 isolates.Among them Scolecobasidium pallescens is a new species,while Myrothecium inundatum,Oidiodendron flavum,Oidiodendron truncatum,Scopulariopsis chartarum are new records to China.Scolecobasidium pallescens is characterized by its relatively light coloured(pale brown)conidia and conidiophores,differing from its similar species,S.microspora.Latin diagnosis is given for the new species.Brief descriptions and illustrations of the new records are provided based on Chinese isolates.The other 13 species being previously known from China in several genera are also listed.All specimens(dried cultures and slides)and living cultures studied have been deposited in the Herbarium of Shandong Agricultural University:Plant Pathology(HSAUP).

  10. Study of the Lead Source in the Surrounding Soil of the Lead-zinc Smelters by Isotope Tracing%铅锌冶炼厂周边土壤铅源的铅同位素示踪

    Institute of Scientific and Technical Information of China (English)

    于凯; 李旭祥; 支泽林; 王海波; 郑刘孙

    2014-01-01

    Taken the soil samples nearby a lead-zinc smelter as the research object,the lead content of the lead-zinc ore,the metallurgical coal and the nearby soil were detected.It was concluded that lead content in the soil surrounding the lead-zinc smelter varied from 22.73 mg/kg to 126.51 mg/kg,and the average content was 42.68 mg/kg which was higher by a factor of 1.85 than the local soil background level.Meanwhile the possible contamination sources were analyzed by means of the spatial variability analysis and the lead isotope mixed model formula.It was concluded that the spatial distribution of soil heavy metal nearby the lead-zinc smelter and the lead isotope rates were close to the metallurgical coal and so that the metallurgical coal was the largest contribu-tion to the soil pollution.%以某铅锌冶炼厂周边土壤为研究对象,通过对其原料及周边土壤中铅含量的检测,结果显示:该冶炼厂周边土壤铅质量比在22.73 mg/kg~126.51 mg/kg之间,平均值为42.68 mg/kg,是当地土壤铅背景值的1.85倍。采用铅质量比空间分布分析和同位素混合模型计算分析了冶炼厂周边土壤中铅的可能来源,分析表明:土壤铅质量比的空间分布及铅同位素比值与冶炼厂的焦化原料煤相近,焦化原料煤对周边土壤铅污染贡献最大。

  11. Notes on soil dematiaceous hyphomycetes from Mount Taibai and its surrounding area, China Ⅰ%太行山及其周围地区土壤中的暗色丝孢菌Ⅰ

    Institute of Scientific and Technical Information of China (English)

    宋伟; 于金凤; 张天宇

    2008-01-01

    A total of 103 isolates of soil dematiaceous hyphomycetes belonging to 27 species in 15 genera were obtained from soil samples of Mount Taibai and its surrounding area, Shaanxi Province, China. Among them Eladia pachyphialis and Gliomastix pallescens are new species, while Acremoniula sarcinellae, Allescheriella crocea, Chrysosporium merdarium, Chrysosporium pannorum are new records to China. The main distinction between E. pachyphialis and its similar species E. saccula is that the phialide of the former is wider and the conidia are smaller than those of the latter. Gliomastix pallescens is characterized by having light colored, long and unbranched conidiophores by which it can be separated from its similar species, G. cerealis. Latin descriptions are given for the new species. Brief descriptions and illustrations of the new records are also provided based on Chinese isolates. The other 21 species being previously known from China in several genera are also listed. All specimens (dried cultures and slides) and living cultures studied have been deposited in the Herbarium of Shandong Agricultural University: Plant Pathology (HSAUP).

  12. Shallow Subsurface Soil Moisture Dynamics in the Root-Zone and Bulk Soil of Sparsely Vegetated Land Surfaces as Impacted by Near-Surface Atmospheric State

    Science.gov (United States)

    Trautz, A.; Illangasekare, T. H.; Tilton, N.

    2015-12-01

    Soil moisture is a fundamental state variable that provides the water necessary for plant growth and evapotranspiration. Soil moisture has been extensively studied in the context of bare surface soils and root zones. Less attention has focused on the effects of sparse vegetation distributions, such as those typical of agricultural cropland and other natural surface environments, on soil moisture dynamics. The current study explores root zone, bulk soil, and near-surface atmosphere interactions in terms of soil moisture under different distributions of sparse vegetation using multi-scale laboratory experimentation and numerical simulation. This research is driven by the need to advance our fundamental understanding of soil moisture dynamics in the context of improving water conservation and next generation heat and mass transfer numerical models. Experimentation is performed in a two-dimensional 7.3 m long intermediate scale soil tank interfaced with a climate-controlled wind tunnel, both of which are outfitted with current sensor technologies for measuring atmospheric and soil variables. The soil tank is packed so that a sparsely vegetated soil is surrounded by bulk bare soil; the two regions are separated by porous membranes to isolate the root zone from the bulk soil. Results show that in the absence of vegetation, evaporation rates vary along the soil tank in response to longitudinal changes in humidity; soil dries fastest upstream where evaporation rates are highest. In the presence of vegetation, soil moisture in the bulk soil closest to a vegetated region decreases more rapidly than the bulk soil farther away. Evapotranspiration rates in this region are also higher than the bulk soil region. This study is the first step towards the development of more generalized models that account for non-uniformly distributed vegetation and land surfaces exhibiting micro-topology.

  13. Speciation analysis and pollution risk assessment of heavy metals in the soils surrounding mine area%矿区周边土壤中重金属形态分析及污染风险评价

    Institute of Scientific and Technical Information of China (English)

    龙海洋; 王维生; 韦月越; 应成璋; 黄雪芬; 蒙敏

    2016-01-01

    为了解某矿区周边土壤的重金属污染状况及污染程度,以广西河池市某矿区周边6处矿山和农田土壤为研究对象,采用湿法消解和BCR连续提取法研究了土壤中重金属( Cd、Zn、Pb和Cu)的总量及形态分布,并用次生相与原生相比值法( RSP)评价了土壤中重金属潜在的生态风险。结果表明,样品中重金属呈现一定的富集效应,总量超过当地土壤背景值和土壤环境质量标准值,从总量超标倍数看,其污染程度为Cd>Zn>Pb抑Cu。 BCR结果显示,离矿山较近的5个采样点的可提取态重金属均占总量的50%以上,有较强的生物有效性和毒性,最远的采样点的重金属主要存在于残渣态中(>60%),可提取态低于40%。 RSP结果显示,离矿山较近的两个采样点的重金属污染风险最高( RSP在1.62~3.20),矿山周边3个采样点有轻度或中度的的污染风险(RSP在1.11~2.16),离矿山最远的采样点几乎没有污染风险(RSP在0.42~0.67)。说明该矿区周边土壤重金属活性较大,离矿区越近,污染风险越高。%In order to understand the pollution condition and level of heavy metals in a mining area and surrounding soils, the contents and speciation distribution of heavy metals ( Cd, Zn, Pb and Cu) in six mine/farmland soils surrounding mine area in Hechi city of Guangxi province were stud-ied by the wet digestion method and BCR sequential extraction procedure . The potential ecological risk of heavy metals in the soils was evaluated by the ratio of secondary phase and primary phase ( RSP) . The results showed that the enrichment of heavy metals in the soils was observed, and the contents of heavy metals were higher than the background values of the local soils, and the values of soil environmental quality standard ( SEQS) . According to the total contents of heavy metals in the soil, the sequence of heavy metal pollution level was obtained as Cd>Zn>Pb-Cu. The results of

  14. Diurnal emissivity dynamics in bare versus biocrusted sand dunes

    Science.gov (United States)

    Rozenstein, O.

    2015-12-01

    Land surface emissivity (LSE) in the thermal infrared depends mainly on the ground cover and on changes in soil moisture. The LSE is a critical variable that affects the prediction accuracy of geophysical models requiring land surface temperature as an input, highlighting the need for an accurate derivation of LSE. The primary aim of this study was to test the hypothesis that diurnal changes in emissivity, as detected from space, are larger for areas mostly covered by biocrusts (composed mainly of cyanobacteria) than for bare sand areas. The LSE dynamics were monitored from geostationary orbit by the Spinning Enhanced Visible and Infrared Imager (SEVIRI) over a sand dune field in a coastal desert region extending across both sides of the Israel-Egypt political borderline. Different land-use practices by the two countries have resulted in exposed, active sand dunes on the Egyptian side (Sinai), and dunes stabilized by biocrusts on the Israeli side (Negev). Since biocrusts adsorb more moisture from the atmosphere than bare sand does, and LSE is affected by the soil moisture, diurnal fluctuations in LSE were larger for the crusted dunes in the 8.7 μm channel. This phenomenon is attributed to water vapor adsorption by the sand / biocrust particles. The results indicate that LSE is sensitive to minor changes in soil water content caused by water vapor adsorption and can, therefore, serve as a tool for quantifying this effect, which has a large spatial impact. As biocrusts cover vast regions in deserts worldwide, this discovery has repercussions for LSE estimations in deserts around the globe, and these LSE variations can potentially have considerable effects on geophysical models from local to regional scales.

  15. Diurnal emissivity dynamics in bare versus biocrusted sand dunes.

    Science.gov (United States)

    Rozenstein, Offer; Agam, Nurit; Serio, Carmine; Masiello, Guido; Venafra, Sara; Achal, Stephen; Puckrin, Eldon; Karnieli, Arnon

    2015-02-15

    Land surface emissivity (LSE) in the thermal infrared depends mainly on the ground cover and on changes in soil moisture. The LSE is a critical variable that affects the prediction accuracy of geophysical models requiring land surface temperature as an input, highlighting the need for an accurate derivation of LSE. The primary aim of this study was to test the hypothesis that diurnal changes in emissivity, as detected from space, are larger for areas mostly covered by biocrusts (composed mainly of cyanobacteria) than for bare sand areas. The LSE dynamics were monitored from geostationary orbit by the Spinning Enhanced Visible and Infrared Imager (SEVIRI) over a sand dune field in a coastal desert region extending across both sides of the Israel-Egypt political borderline. Different land-use practices by the two countries have resulted in exposed, active sand dunes on the Egyptian side (Sinai), and dunes stabilized by biocrusts on the Israeli side (Negev). Since biocrusts adsorb more moisture from the atmosphere than bare sand does, and LSE is affected by the soil moisture, diurnal fluctuations in LSE were larger for the crusted dunes in the 8.7 μm channel. This phenomenon is attributed to water vapor adsorption by the sand/biocrust particles. The results indicate that LSE is sensitive to minor changes in soil water content caused by water vapor adsorption and can, therefore, serve as a tool for quantifying this effect, which has a large spatial impact. As biocrusts cover vast regions in deserts worldwide, this discovery has repercussions for LSE estimations in deserts around the globe, and these LSE variations can potentially have considerable effects on geophysical models from local to regional scales.

  16. Practices Surrounding Event Photos

    NARCIS (Netherlands)

    Vyas, Dhaval; Nijholt, Antinus; van der Veer, Gerrit C.; Kotzé, P.; Marsden, G.; Lindgaard, G.; Wesson, J.; Winckler, M.

    Sharing photos through mobile devices has a great potential for creating shared experiences of social events between co-located as well as remote participants. In order to design novel event sharing tools, we need to develop indepth understanding of current practices surrounding these so called

  17. Electron beam control for barely separated beams

    Science.gov (United States)

    Douglas, David R.; Ament, Lucas J. P.

    2017-04-18

    A method for achieving independent control of multiple beams in close proximity to one another, such as in a multi-pass accelerator where coaxial beams are at different energies, but moving on a common axis, and need to be split into spatially separated beams for efficient recirculation transport. The method for independent control includes placing a magnet arrangement in the path of the barely separated beams with the magnet arrangement including at least two multipole magnets spaced closely together and having a multipole distribution including at least one odd multipole and one even multipole. The magnetic fields are then tuned to cancel out for a first of the barely separated beams to allow independent control of the second beam with common magnets. The magnetic fields may be tuned to cancel out either the dipole component or tuned to cancel out the quadrupole component in order to independently control the separate beams.

  18. Hvorfor siger vi ikke bare ugh?!

    DEFF Research Database (Denmark)

    Pálfi, Loránd-Levente

    2009-01-01

    Det danske sprog er ramt af en flerdobbelt katastrofe: De unge i folkeskolerne og gymnasierne taler og skriver et stadigt dårligere dansk, og forskningen i dansk sprog går i stå. Og Dansk Sprognævn, som burde stå vagt om sproget, lader ikke bare stå til, men ophæver forfaldet til lov. Er en "B-fi...

  19. Fishbone Instability Excited by Barely Trapped Electrons

    Institute of Scientific and Technical Information of China (English)

    WANG Zhong-Tian; LONG Yong-Xing; DONG Jia-Qi; WANG Long; Fulvio Zonca

    2006-01-01

    Fishbone instability excited by barely trapped suprathermal electrons (BTSEs) in tokamaks is investigated theoretically. The frequency of the mode is found to close to procession frequency of BTSEs. The growth rate of the mode is much smaller than that of the ideal magnetohytrodynamic (MHD) internal kink mode that is in contrast to the case of trapped ion driven fishbone instability. The analyses also show that spatial density gradient reversal is necessary for the instability. The correlation of the results with experiments is discussed.

  20. 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...

  1. Water Accommodation on Bare and Coated Ice

    Science.gov (United States)

    Kong, Xiangrui

    2015-04-01

    A good understanding of water accommodation on ice surfaces is essential for quantitatively predicting the evolution of clouds, and therefore influences the effectiveness of climate models. However, the accommodation coefficient is poorly constrained within the literature where reported values vary by up to three orders of magnitude. In addition, the complexity of the chemical composition of the atmosphere plays an important role in ice phase behavior and dynamics. We employ an environmental molecular beam (EMB) technique to investigate molecular water interactions with bare and impurity coated ice at temperatures from 170 K to 200 K. In this work, we summarize results of water accommodation experiments on bare ice (Kong et al., 2014) and on ice coated by methanol (Thomson et al., 2013), butanol (Thomson et al., 2013) and acetic acid (Papagiannakopoulos et al., 2014), and compare those results with analogous experiments using hexanol and nitric acid coatings. Hexanol is chosen as a complementary chain alcohol to methanol and butanol, while nitric acid is a common inorganic compound in the atmosphere. The results show a strong negative temperature dependence of water accommodation on bare ice, which can be quantitatively described by a precursor model. Acidic adlayers tend to enhance water uptake indicating that the system kinetics are thoroughly changed compared to bare ice. Adsorbed alcohols influence the temperature dependence of the accommodation coefficient and water molecules generally spend less time on the surfaces before desorbing, although the measured accommodation coefficients remain high and comparable to bare ice for the investigated systems. We conclude that impurities can either enhance or restrict water uptake in ways that are influenced by several factors including temperature and type of adsorbant, with potential implications for the description of ice particle growth in the atmosphere. This work was supported by the Swedish Research Council and

  2. 30 CFR 57.12080 - Bare conductor guards.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Bare conductor guards. 57.12080 Section 57... Underground Only § 57.12080 Bare conductor guards. Trolley wires and bare power conductors shall be guarded at... conductors are less than 7 feet above the rail, they shall be guarded at all points where persons work...

  3. 30 CFR 57.12012 - Bare signal wires.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Bare signal wires. 57.12012 Section 57.12012 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE... and Underground § 57.12012 Bare signal wires. The potential on bare signal wires accessible to contact...

  4. 30 CFR 56.12012 - Bare signal wires.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Bare signal wires. 56.12012 Section 56.12012 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE... Bare signal wires. The potential on bare signal wires accessible to contact by persons shall not exceed...

  5. Ikke bare porno på mobilen

    DEFF Research Database (Denmark)

    Andersen, Tem Frank

    2013-01-01

    Den britiske børne- og ungdomsforsker professor Sonia Livingstone ved London School of Economics viser gennem en række interviews, at billeder af eksplicitte sexhandlinger er en velkendt del af den ungdommelige cirkulation af ’hverdagspornografisk’ materiale (Ringrose et al. 2012). ’Sexting’ er...... altså ikke bare porno på en mobilplatform. Det er handlinger og værgestrategier, som unge piger er nødt til at forholde sig til i hverdagen, mens drengene umiddelbart ser ud til at slippe relativt let udenom den chikane, der kan ligge i ’sexting’....

  6. Chirality in Bare and Passivated Gold Nanoclusters

    CERN Document Server

    Garzon, I L; Rodrigues-Hernandez, J I; Sigal, I; Beltran, M R; Michaelian, K

    2002-01-01

    Chiral structures have been found as the lowest-energy isomers of bare (Au$_{28}$ and Au$_{55}) and thiol-passivated (Au$_{28}(SCH$_{3})$_{16}$ and Au$_{38}$(SCH$_{3}$)$_{24}) gold nanoclusters. The degree of chirality existing in the chiral clusters was calculated using the Hausdorff chirality measure. We found that the index of chirality is higher in the passivated clusters and decreases with the cluster size. These results are consistent with the observed chiroptical activity recently reported for glutahione-passivated gold nanoclusters, and provide theoretical support for the existence of chirality in these novel compounds.

  7. Do Bare Rocks Exist on the Moon?

    Science.gov (United States)

    Allen, Carlton; Bandfield, Joshua; Greenhagen, Benjamin; Hayne, Paul; Leader, Frank; Paige, David

    2017-01-01

    Astronaut surface observations and close-up images at the Apollo and Chang'e 1 landing sites confirm that at least some lunar rocks have no discernable dust cover. However, ALSEP (Apollo Lunar Surface Experiments Package) measurements as well as astronaut and LADEE (Lunar Atmosphere and Dust Environment Explorer) orbital observations and laboratory experiments possibly suggest that a fine fraction of dust is levitated and moves across and above the lunar surface. Over millions of years such dust might be expected to coat all exposed rock surfaces. This study uses thermal modeling, combined with Diviner (a Lunar Reconnaissance Orbiter experiment) orbital lunar eclipse temperature data, to further document the existence of bare rocks on the lunar surface.

  8. Analysing land cover and land use change in the Matobo National Park and surroundings in Zimbabwe

    Science.gov (United States)

    Scharsich, Valeska; Mtata, Kupakwashe; Hauhs, Michael; Lange, Holger; Bogner, Christina

    2016-04-01

    Natural forests are threatened worldwide, therefore their protection in National Parks is essential. Here, we investigate how this protection status affects the land cover. To answer this question, we analyse the surface reflectance of three Landsat images of Matobo National Park and surrounding in Zimbabwe from 1989, 1998 and 2014 to detect changes in land cover in this region. To account for the rolling countryside and the resulting prominent shadows, a topographical correction of the surface reflectance was required. To infer land cover changes it is not only necessary to have some ground data for the current satellite images but also for the old ones. In particular for the older images no recent field study could help to reconstruct these data reliably. In our study we follow the idea that land cover classes of pixels in current images can be transferred to the equivalent pixels of older ones if no changes occurred meanwhile. Therefore we combine unsupervised clustering with supervised classification as follows. At first, we produce a land cover map for 2014. Secondly, we cluster the images with clara, which is similar to k-means, but suitable for large data sets. Whereby the best number of classes were determined to be 4. Thirdly, we locate unchanged pixels with change vector analysis in the images of 1989 and 1998. For these pixels we transfer the corresponding cluster label from 2014 to 1989 and 1998. Subsequently, the classified pixels serve as training data for supervised classification with random forest, which is carried out for each image separately. Finally, we derive land cover classes from the Landsat image in 2014, photographs and Google Earth and transfer them to the other two images. The resulting classes are shrub land; forest/shallow waters; bare soils/fields with some trees/shrubs; and bare light soils/rocks, fields and settlements. Subsequently the three different classifications are compared and land changes are mapped. The main changes are

  9. 浑善达克沙地光合/非光合植被及裸土光谱混合机理分析%Spectral Mixing Mechanism Analysis of Photosynthetic/Non-Photosynthetic Vegetation and Bared Soil Mixture in the Hunshandake (Otindag) Sandy Land

    Institute of Scientific and Technical Information of China (English)

    郑国雄; 李晓松; 张凯选; 王金英

    2016-01-01

    研究浑善达克沙地光合/非光合植被(photosynthetic/non‐photosynthetic vegetation ,PV/NPV)及裸土(bared soil ,BS )光谱混合机理,对于构建沙地最佳光谱混合模型、准确估算沙地地表植被覆盖信息具有重要意义。本研究通过两景覆盖研究区的Hyperion高光谱影像获取47个典型混合样地对应混合光谱信息,利用地面实测获取PV/N PV及BS端元光谱和每个样地各端元丰度信息,然后分别尝试采用线性光谱混合模型和非线性光谱混合模型对所有样地混合光谱进行分解计算光合植被覆盖度(fractional cover of photosyn‐thetic vegetation , fpv )和非光合植被覆盖度(fractional cover of non‐photosynthetic vegetation , fnpv ),通过比较不同模型分解均方根误差及PV/N PV覆盖度估算精度来探索浑善达克沙地PV/N PV及BS之间光谱混合形成机理,寻求适合其 fpv与 fnpv估算的最佳光谱混合模型。结果表明:对于浑善达克沙地来说,基于PV/NPV及BS的线性光谱混合模型可以实现 fpv与 fnpv的较好估算, fpv估算的均方根误差为0.12(R2=0.84), fnpv估算的均方根误差为0.13(R2=0.66);考虑多重散射影响的非线性光谱混合模型无论在模型分解精度还是在 f pv与 f npv估算精度上均没有明显提升,其中各端元之间的多重散射作用对 f pv估算精度的影响不大,但会导致 f npv估算精度的明显降低。%Analysis of spectral mixing mechanism of photosynthetic vegetation (PV)/non‐photosynthetic vegetation (NPV) and bared soil (BS) mixture would be essential to establish the optimal spectral mixture model and further improve the estimation ac‐curacy of sparse vegetation coverage in Hunshandake (Otindag) sandy land ,Inner Mongolia of China .Over the past several dec‐ades ,remote sensing has been widely utilized for estimating the fractional cover of vegetation .However ,most

  10. Analysing land cover and land use change in the Ruma National Park and surroundings in Kenya

    Science.gov (United States)

    Scharsich, Valeska; Ochuodho Otieno, Dennis; Bogner, Christina

    2017-04-01

    The change of land use and land cover (LULC) is often driven by the growth of human population. In the Lambwe valley, Kenya, the most important reason for accelerated settlement in the last decades was the control of the tsetse fly, the biological vector of trypanosomes. Since the huge efforts of tsetse control in the 1970s, the population of the Lambwe valley in Kenya increased rapidly and therefore the cultivated area expanded. This amplified the pressure on the forested areas at higher elevations and the Ruma National Park which occupies one third of the Lambwe valley. Here, we investigate possible effects of this pressure on the land cover in the Lambwe valley and in particular in the Ruma National Park. To answer this question, we analysed the surface reflectance of three Landsat images of Ruma National Park and its surroundings from 1984, 2002 and 2014. To compensate for the lack of ground data we inferred past land use and land cover from recent observations combining Google Earth images and change detection. By supervised classification with Random Forests, we identified four land use and land cover types, namely the forest dominant at the high elevation; dense shrub land; savanna; and sparsely covered soil including bare light soils with little vegetation, fields and settlements. Subsequently, we compared the three classifications and identified LULC changes that occurred between 1984 and 2014. We observed an increase of agricultural area in the western part of the Lambwe valley, where high elevation vegetation was dominant. This goes hand in hand with farming on higher slopes and a decrease of forest. In the National Park itself the savanna increased by about 8% and the proportion of sparsely covered soil decreased by about 10%. This might be due to the fire management in the park and the recovering of burned areas.

  11. Fire testing of bare uranium hexafluoride cylinders

    Energy Technology Data Exchange (ETDEWEB)

    Pryor, W.A. [PAI Corp., Oak Rige, TN (United States)

    1991-12-31

    In 1965, the Oak Ridge Gaseous Diffusion Plant (ORGDP), now the K-25 Site, conducted a series of tests in which bare cylinders of uranium hexafluoride (UF{sub 6}) were exposed to engulfing oil fires for the US Atomic Energy Commission (AEC), now the US Department of Energy (DOE). The tests are described and the results, conclusions, and observations are presented. Two each of the following types of cylinders were tested: 3.5-in.-diam {times} 7.5-in.-long cylinders of Monel (Harshaw), 5.0-in.-diam {times} 30-in.-long cylinders of Monel, and 8-in.-diam {times} 48-in.-long cylinders of nickel. The cylinders were filled approximately to the standard UF{sub 6} fill limits of 5, 55, and 250 lb, respectively, with a U-235 content of 0.22%. The 5-in.- and 8-in.-diam cylinders were tested individually with and without their metal valve covers. For the 3.5-in.-diam Harshaw cylinders and the 5.0-in.-diam cylinder without a valve cover the valves failed and UF{sub 6} was released. The remaining cylinders ruptured explosively in time intervals ranging from about 8.5 to 11 min.

  12. Fire testing of bare uranium hexafluoride cylinders

    Energy Technology Data Exchange (ETDEWEB)

    Pryor, W.A. [PAI Corp., Oak Ridge, TN (United States)

    1991-12-31

    In 1965, the Oak Ridge Gaseous Diffusion Plant (ORGDP), now the K-25 Site, conducted a series of tests in which bare cylinders of uranium hexafluoride (UF{sub 6}) were exposed to engulfing oil fires for the US Atomic Energy Commission (AEC), now the US Department of Energy (DOE). The tests are described and the results, conclusions, and observations are presented. Two each of the following types of cylinders were tested: 3.5-in.-diam {times} 7.5-in.-long cylinders of Monel (Harshaw), 5.0-in.-diam {times} x 30-in.-long cylinders of Monel, and 8-in.-diam {times} 48-in.-long cylinders of nickel. The cylinders were filled approximately to the standard UF{sub 6} fill limits of 5, 55, and 250 lb, respectively, with a U-235 content of 0.22%. The 5-in.- and 8-in.-diam cylinders were tested individually with and without their metal valve covers. For the 3.5-in.-diam Harshaw cylinders and the 5.0-in.-diam cylinder without a valve cover, the valves failed and UF{sub 6} was released. The remaining 6 cylinders ruptured explosively in time intervals ranging from about 8.5 to 11 min.

  13. Clinical Application of Surrounding Puncture

    Institute of Scientific and Technical Information of China (English)

    GUO Yao-jie; HAN Chou-ping

    2003-01-01

    Surrounding puncture can stop pathogenic qi from spreading, consolidate the connection between local meridians and enrich local qi and blood, which can eventually supplement anti-pathogenic qi and remove pathogenic qi, and consequently remedy diseases. The author of this article summrized and analyzed the clinical application of surrounding puncture for the purpose of studying this technique and improving the therapeutic effect.

  14. Role of water in the tribochemical removal of bare silicon

    Science.gov (United States)

    Chen, Cheng; Xiao, Chen; Wang, Xiaodong; Zhang, Peng; Chen, Lei; Qi, Yaqiong; Qian, Linmao

    2016-12-01

    Nanowear tests of bare silicon against a SiO2 microsphere were conducted in air (relative humidity [RH] = 0%-89%) and water using an atomic force microscope. Experimental results revealed that the water played an important role in the tribochemical wear of the bare silicon. A hillock-like wear trace with a height of 0.7 nm was generated on the bare silicon surface in dry air. As the RH increased, the wear depth increased and reached the maximum level in water. Analysis of frictional dissipated energy suggested that the wear of the bare silicon was not dominated by mechanical interactions. High-resolution transmission electron microscopy detection demonstrated that the silicon atoms and crystal lattice underneath the worn area maintained integral perfectly and thus further confirmed the tribochemical wear mechanism of the bare silicon. Finally, the role of water in the tribochemical wear of the bare silicon may be explained by the following three aspects: the hydroxylation by hydroxyl ions auto-ionized in water, the hydrolytic reaction of water molecules, and the dissolution of the tribochemical product SiOmHn in liquid water. With increasing RH, a greater water amount would adsorb to the Si/SiO2 interface and induce a more serious tribochemical wear on the bare silicon surface. The results of this paper may provide further insight into the tribochemical removal mechanism of bare monocrystalline silicon and furnish the wider reaction cognition for chemical mechanical polishing.

  15. The Semantics of Proper Names and Other Bare Nominals

    Science.gov (United States)

    Izumi, Yu

    2012-01-01

    This research proposes a unified approach to the semantics of the so-called bare nominals, which include proper names (e.g., "Mary"), mass and plural terms (e.g., "water," "cats"), and articleless noun phrases in Japanese. I argue that bare nominals themselves are monadic predicates applicable to more than one…

  16. Enhanced Built-Up and Bareness Index (EBBI for Mapping Built-Up and Bare Land in an Urban Area

    Directory of Open Access Journals (Sweden)

    I Wayan Arthana

    2012-10-01

    Full Text Available Remotely sensed imagery is a type of data that is compatible with the monitoring and mapping of changes in built-up and bare land within urban areas as the impacts of population growth and urbanisation increase. The application of currently available remote sensing indices, however, has some limitations with respect to distinguishing built-up and bare land in urban areas. In this study, a new index for transforming remote sensing data for mapping built-up and bare land areas is proposed. The Enhanced Built-Up and Bareness Index (EBBI is able to map built-up and bare land areas using a single calculation. The EBBI is the first built-up and bare land index that applies near infrared (NIR, short wave infrared (SWIR, and thermal infrared (TIR channels simultaneously. This new index was applied to distinguish built-up and bare land areas in Denpasar (Bali, Indonesia and had a high accuracy level when compared to existing indices. The EBBI was more effective at discriminating built-up and bare land areas and at increasing the accuracy of the built-up density percentage than five other indices.

  17. Isolation and biocontrol potential of bacteria and actinomycetes from soils suppressive to Rhizoctonia bare-patch disease in South Australia%南澳大利亚丝核菌抑病土中细菌与放线菌的分离及其对病害的生物防治作用

    Institute of Scientific and Technical Information of China (English)

    杨合同; Maarten RYDER; 唐文华

    2005-01-01

    Bacteria and actinomycetes were quantitatively isolated from a soil collected from Avon, South Australia, which is suppressive to wheat bare-patch disease caused by Rhizoctonia solani anastomosis group 8. The percentage of isolates antagonistic to R. solani AG-8 isolate 21 was measured from the total population of bacteria and actinomycetes. Heat treatment (60℃, 10min.), a process previously shown to remove the suppressive qualities of this soil, significantly reduced the counts of total bacteria and actinomycetes on agar plates, but did not reduce the percentage of antagonists. Nine isolates were chosen from 2700 isolates, based on their strong inhibition of R. solani AG-8 isolate 21, Gaeumannomyces graminis var. tritici (Ggt) isolate 8, Fusarium graminearum isolate Fg, Verticillium dahliae isolate Vd5, Bipolaris sorokiniana isolate Bs, Pythium irregulare isolate BH40, and Rhizoctonia solani AG-4 isolate 1664 causing damping-off of cotton. Seven of the nine antagonistic isolates were either chitinase-or endoglucanase-positive, with strong chitinase production appearing to be associated with strong biocontrol activity.The nine antagonistic isolates were identified as Bacillus megaterium (isolate Ap25), B. subtilis (isolate Ap113), Streptomyces spp. (isolate Ap117), Bacillus coagulans (isolate Ap123), Streptoverticillium reticulum (isolate Ap89), Cellulomonas flavigena (isolate Ap75) or were actinomycetes (isolates Ap116, Ap111 and Ap139).B. megaterium Ap25 and B. subtilis Ap113 were the most effective in disease reduction and seedling growth promotion.These two isolates were inhibitory in vitro to a beneficial Trichoderma pseudokoningii isolate A5MH, which was isolated from the same soil sample, but did not significantly reduce the efficacy of A5MH in disease control and seedling growth promotion.%从南澳大利亚埃文采集的土壤样品中计数分离了细菌和放线菌,该土壤对Rhizoctonia solani 融合群8引起的小麦根腐病具有抑制作

  18. Visual surround suppression in schizophrenia

    Directory of Open Access Journals (Sweden)

    Marc Samuel Tibber

    2013-02-01

    Full Text Available Compared to unaffected observers patients with schizophrenia show characteristic differences in visual perception, including a reduced susceptibility to the influence of context on judgements of contrast - a manifestation of weaker surround suppression. To examine the generality of this phenomenon we measured the ability of 24 individuals with schizophrenia to judge the luminance, contrast, orientation and size of targets embedded in contextual surrounds that would typically influence the target’s appearance. Individuals with schizophrenia demonstrated weaker surround suppression compared to matched controls for stimuli defined by contrast or size, but not for those defined by luminance or orientation. As perceived luminance is thought to be regulated at the earliest stages of visual processing our findings are consistent with a suppression deficit that is predominantly cortical in origin. In addition, we propose that preserved orientation surround suppression in schizophrenia may reflect the sparing of broadly tuned mechanisms of suppression. We attempt to reconcile these data with findings from previous studies.

  19. Educational Success and Surrounding Culture

    Science.gov (United States)

    Walters, Garrison

    2016-01-01

    The curriculum, instruction, and services we provide in schools, colleges, and universities matter a lot, but if we continue to ignore our students' "surrounding culture," progress toward a more educated nation will continue to be disappointing.

  20. Educational Success and Surrounding Culture

    Science.gov (United States)

    Walters, Garrison

    2016-01-01

    The curriculum, instruction, and services we provide in schools, colleges, and universities matter a lot, but if we continue to ignore our students' "surrounding culture," progress toward a more educated nation will continue to be disappointing.

  1. Multichannel spatial surround sound system

    Institute of Scientific and Technical Information of China (English)

    RAO Dan; XIE Bosun

    2004-01-01

    Based on the consideration of being compatible with 5.1 channel horizontal surround sound system, a spatial surround sound system is proposed. Theoretical and experimental results show that the system has a wide listening area. It can not only recreate stable image in the front and rear direction, but also eliminate the defect of poor lateral image of 5.1 channel system. The system can be used to reproduce special 3D sound effect and the spaciousness of hall.

  2. Emission of SO2 and SO4 2-: From copper smelter and its influence on the level of total S in soil and moss in Bor, Serbia, and the surroundings

    OpenAIRE

    Šerbula Snežana M.; Ţivković Dragana T.; Radojević Ana A.; Kalinović Tanja S.; Kalinović Jelena V.

    2015-01-01

    Bor and the surroundings (Eastern Serbia) have been known for exploitation and processing of sulphide copper ores for more than 100 years. Emissions of waste gases and particulate matter rich in heavy metals are characteristic for pyrometallurgical production of copper. Long-term measurement results (2005-2008) indicate an increased sulphur dioxide level in the urban-industrial zone of Bor since it is closest to the copper smelter which is a dominant source...

  3. A Syntactic Study on Bare Infinitive and Infinitival to

    Institute of Scientific and Technical Information of China (English)

    LIU Jing

    2014-01-01

    Infinitives which consist of bare infinitive and infinitival to are imperative in linguistic studies. And both of the two kinds of infinitives do not indicate person, tense and number. This research aims to analyze the properties, similarities and differ-ences between bare infinitive and infinitival to from the perspective of syntax. Thus, it enables us to attain a uniform characteriza-tion of the infinitival to and bare infinitive on the syntactic level and help us to understand these two kinds of infinitives better.

  4. Models for calculating phreatic water evaporation on bare and Tamarix-vegetated lands

    Institute of Scientific and Technical Information of China (English)

    HU Shunjun; TIAN Changyan; SONG Yudong; CHEN Xiaobing; LI Yuetan

    2006-01-01

    Groundwater is the main source of water consumption of natural vegetation in arid regions.It is an effective approach to study ecological water demand of natural vegetation by phreatic evaporation.In order to study the ecological water demand of Tarim river basin, based on the observation data of phreatic evaporation on bare lands at the Aksu Water Balance Experimental station from 1989 to 1996, by analyzing the relationship of phreatic evaporation,depth of phreatic surface and evaporation of water,taking the limit rate of phreatic evaporation as the control condition, and based on the objective law that the relation between phreatic evaporation and evaporation of water is nonlinear, we establish models for calculating phreatic evaporation on bare land,which can fully reflect the law of phreatic evaporation in the Tarim river basin. According to the data of depth of phreatic surface and soil moisture when pheratic level decline is caused just by evapotranspiration on Tamarix-vegetated land from 2003 to 2004, we calculate the amount of phreatic evaporation and set up models for calculating phreatic evaporation on Tamarix- vegetated land. Phreatic evaporation on bare land and Tamarix-vegetated land could be transformed each other by a Tamarix vegetation conversion coefficient. The test results show that the calculation accuracy of the models is high and the models are suitable for Tarim river basin.

  5. EAARL Coastal Topography--Pearl River Delta 2008: Bare Earth

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — A bare earth elevation map (also known as a Digital Elevation Model, or DEM) of the Pearl River Delta in Louisiana and Mississippi was produced from remotely sensed,...

  6. EAARL Coastal Topography--Northeast Barrier Islands 2007: Bare Earth

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — A bare earth elevation map (also known as a Digital Elevation Model, or DEM) of the northeast coastal barrier islands in New York and New Jersey was produced from...

  7. EAARL Coastal Topography - Northern Gulf of Mexico, 2007: Bare earth

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — A bare earth elevation map (also known as a Digital Elevation Model, or DEM) of the northern Gulf of Mexico barrier islands and Naval Live Oaks was produced from...

  8. EAARL Coastal Topography--Pearl River Delta 2008: Bare Earth

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — A bare earth elevation map (also known as a Digital Elevation Model, or DEM) of the Pearl River Delta in Louisiana and Mississippi was produced from remotely sensed,...

  9. EAARL Coastal Topography--Chandeleur Islands, Louisiana, 2010: Bare Earth

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — A bare-earth digital elevation map (also known as a Digital Elevation Model, or DEM) of a portion of the Chandeleur Islands, Louisiana, was produced from remotely...

  10. EAARL Bare Earth Topography-Fire Island National Seashore

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — A bare earth elevation map (also known as a Digital Elevation Model or DEM) of Fire Island National Seashore was produced from remotely-sensed,...

  11. EAARL Coastal Topography--Northeast Barrier Islands 2007: Bare Earth

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — A bare earth elevation map (also known as a Digital Elevation Model, or DEM) of the northeast coastal barrier islands in New York and New Jersey was produced from...

  12. EAARL Topography-Vicksburg National Millitary Park 2008: Bare Earth

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — A bare earth elevation map (also known as a Digital Elevation Model, or DEM) of the Vicksburg National Military Park in Mississippi was produced from remotely...

  13. EAARL Coastal Topography - Northern Gulf of Mexico, 2007: Bare earth

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — A bare earth elevation map (also known as a Digital Elevation Model, or DEM) of the northern Gulf of Mexico barrier islands and Naval Live Oaks was produced from...

  14. Temporal construals of bare predicates in Mandarin Chinese

    NARCIS (Netherlands)

    Sun, Hongyuan

    2014-01-01

    This dissertation contributes to the research on tense and eventualities across languages. It presents the first systematic investigation and detailed theoretical analysis of the temporal interpretations of sentences with bare (aspectually unmarked) predicates in Mandarin. Traditionally considered

  15. EAARL Coastal Topography--Chandeleur Islands, Louisiana, 2010: Bare Earth

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — A bare-earth digital elevation map (also known as a Digital Elevation Model, or DEM) of a portion of the Chandeleur Islands, Louisiana, was produced from remotely...

  16. EAARL Bare Earth Topography-Fire Island National Seashore

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — A bare earth elevation map (also known as a Digital Elevation Model or DEM) of Fire Island National Seashore was produced from remotely-sensed,...

  17. EAARL Topography-Vicksburg National Millitary Park 2008: Bare Earth

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — A bare earth elevation map (also known as a Digital Elevation Model, or DEM) of the Vicksburg National Military Park in Mississippi was produced from remotely...

  18. Bare and effective fluid description in brane world cosmology

    Energy Technology Data Exchange (ETDEWEB)

    Cruz, Norman [Universidad de Santiago, Departamento de Fisica, Facultad de Ciencia, Casilla 307, Santiago (Chile); Lepe, Samuel; Saavedra, Joel [Pontificia Universidad Catolica de Valparaiso, Instituto de Fisica, Casilla 4950, Valparaiso (Chile); Pena, Francisco [Universidad de La Frontera, Departamento de Ciencias Fisicas, Facultad de Ingenieria, Ciencias y Administracion, Avda. Francisco Salazar 01145, Casilla 54-D, Temuco (Chile)

    2010-03-15

    An effective fluid description, for a brane world model in five dimensions, is discussed for both signs of the brane tension. We found several cosmological scenarios where the effective equation differs widely from the bare equation of state. For universes with negative brane tension, with a bare fluid satisfying the strong energy condition, the effective fluid can cross the barrier {omega} {sub eff}=-1. (orig.)

  19. Growth and nutrition of Tetraclinis articulata (Vahl Mast. cultivated in different rhizosphere soils collected from Tetraclinis stand

    Directory of Open Access Journals (Sweden)

    Abbas, Y.

    2013-01-01

    Full Text Available Five representative plant species (Withania frutescens Pauquy, Lavandula multifida L., Pistacia atlantica Desf., Olea europaea L. subsp. oleaster (Hoffmanns. & Link Negodi and Tetraclinis articulata [Vahl] Mast. were selected from Moroccan Tetraclinis woodland in order to evaluate their mycorrhizal potential and to compare the impact of their rhizosphere soil on growth and nutrition of Tetraclinis articulata seedlings. We observed that roots of selected plants were highly colonized by Arbuscular Mycorrhizal (AM fungi. Lavandula multifida roots showed the highest colonization percentage (100%. We recovered AM fungal spores from the rhizosphere soils of the five plant species and we found that the spores number from L. multifida and T. articulata rhizosphere was significantly different from that of other plants. We assessed the mycorrhizal potential of the indigenous soils by using the Most Probable Number (MPN approach. We found that MPN in soils collected near the five plant species was significantly higher than the one in the bare soil. The average of MPN per 100 g of dry soil was 11.8 (from 5.6 to 25.0 in the bare soil and 228.5 (from 108.0 to 476.0 in L. multifida rhizosphere. This result indicates that the soil surrounding the target plants can be used as inoculum for mycorrhization. We conducted a nursery experiment in which L. multifida soil yielded a high mycorrhizal percentage in T. articulata plants, thus contributing to improve the plant growth. However, the highest formation of arbuscules in T. articulata grown in Lavandula soil did not significantly affect the growth or the nutrition of plants compared to Tetraclinis soil, except for potassium concentration. Our investigation clearly showed that L. multifida soil can be used as biofertilizer to inoculate nurseries for T. articulata production. This will greatly contribute to sustain Tetraclinis woodland.

  20. Killing, letting die and the bare difference argument.

    Science.gov (United States)

    Perrett, Roy W

    1996-04-01

    I believe that there is no intrinsic moral difference between killing and letting die. That is, there is no difference that depends solely on the distinction between an act and an omission. I also believe that we can reasonably establish this thesis by appeal to the Bare Difference Argument. The form of this argument involves considering two imaginary cases in which there are no morally relevant differences present, save the bare difference that one is a case of killing and one a case of letting die. But in the pair of cases under consideration this bare difference makes no moral difference. Hence it cannot be that the bare difference between killing and letting die is in itself a morally important difference. Winston Nesbitt has recently argued that the Bare Difference Argument fails because "the examples produced typically possess a feature which makes their use in this context illegitimate, and that when modified to remove this feature, they provide support for the view which they were designed to undermine". I argue that Nesbitt misunderstands the logic of the Bare Difference Argument and that accordingly his objections are mistaken.

  1. Visual Surround Suppression in Schizophrenia

    Science.gov (United States)

    Tibber, Marc S.; Anderson, Elaine J.; Bobin, Tracy; Antonova, Elena; Seabright, Alice; Wright, Bernice; Carlin, Patricia; Shergill, Sukhwinder S.; Dakin, Steven C.

    2013-01-01

    Compared to unaffected observers patients with schizophrenia (SZ) show characteristic differences in visual perception, including a reduced susceptibility to the influence of context on judgments of contrast – a manifestation of weaker surround suppression (SS). To examine the generality of this phenomenon we measured the ability of 24 individuals with SZ to judge the luminance, contrast, orientation, and size of targets embedded in contextual surrounds that would typically influence the target’s appearance. Individuals with SZ demonstrated weaker SS compared to matched controls for stimuli defined by contrast or size, but not for those defined by luminance or orientation. As perceived luminance is thought to be regulated at the earliest stages of visual processing our findings are consistent with a suppression deficit that is predominantly cortical in origin. In addition, we propose that preserved orientation SS in SZ may reflect the sparing of broadly tuned mechanisms of suppression. We attempt to reconcile these data with findings from previous studies. PMID:23450069

  2. Semantic coherence in English accusative-with-bare-infinitive constructions

    DEFF Research Database (Denmark)

    Jensen, Kim Ebensgaard

    2013-01-01

    Drawing on usage-based cognitively oriented construction grammar, this paper investigates the patterns of coattraction of items that appear in the two VP positions (the VP in the matrix clause, and the VP in the infinitive subordinate clause) in the English accusative-with-bare-infinitive constru......Drawing on usage-based cognitively oriented construction grammar, this paper investigates the patterns of coattraction of items that appear in the two VP positions (the VP in the matrix clause, and the VP in the infinitive subordinate clause) in the English accusative......-with-bare-infinitive construction. The main methodological framework is that of covarying collexeme analysis, which, through statistical corpus analysis, allows for the analyst to address the semantics of a construction. Using this method on data from the BNC, the ultimate purpose of the paper is to address the underlying semantic...... relations of English accusatives-with-bare-infinitives through the relations of semantic coherence between the two VPs....

  3. The role of termites and mulch in the rehabilitation of crusted Sahelian soils.

    NARCIS (Netherlands)

    Mando, A.

    1997-01-01

    During recent decades Sahelian soils have gone through various forms of degradation, the most spectacular one being the extension of bare and crusted soils. Mulch, when placed on a crusted and bare soil, triggers termite activity within a few months. Many burrows are opened through the sealed surfac

  4. Survival of Ancylostoma caninum on bare ground, pea gravel, and concrete.

    Science.gov (United States)

    Mark, D L

    1975-12-01

    Studies were done to determine the survival of infective Ancylostoma caninum 3rd-stage larvae on 3 ground covers commonly used in dog run construction: bare ground, pea gravel, and concrete. Changes in numbers of recovered larvae were compared to meterologic data and the most significant weather variables were determined. Larvae were recovered 1 to 7 days on bare ground. Larvae survived longer in the fecal mass (mean of 3 days) than on the bare ground (mean of 2 days). Rain was the most significant variable, in that it was positive in its effects (higher larval count) early in the experiment (causing fecal mass breakdown and release of larvae) and negative (lower larval count) later in the experiment (spreading larvae away from test site). Larvae were also recovered 1 to 7 days on pea gravel. They were recovered for a mean 2.6 days from the fecal sample, a mean of 1.5 days from the rocks directly below the fecal mass, and a mean of 1.3 days from the remaining rocks. Here also, rain was the most significant weather factor. It was negatively significant (lower larval count) for the fecal mass (spreading of the larvae) and positive for those in the pebbles (increasing the moisture in the pebbles). Survival time of larvae on concrete was shorter than that on the other 2 substrates: from 0 to 2 days. Larvae were recovered a mean of 1.3 days from the fecal mass and a mean of 0., days from the surrounding concrete. Rain was positively significant early in the experiments in that it released trapped larvae from the fecal mass. Sunlight consistently was negatively significant (lower larval count) due to its lethality to the unprotected larvae.

  5. Semantic coherence in English accusative-with-bare-infinitive constructions

    DEFF Research Database (Denmark)

    Jensen, Kim Ebensgaard

    2013-01-01

    Drawing on usage-based cognitively oriented construction grammar, this paper investigates the patterns of coattraction of items that appear in the two VP positions (the VP in the matrix clause, and the VP in the infinitive subordinate clause) in the English accusative-with-bare-infinitive constru......Drawing on usage-based cognitively oriented construction grammar, this paper investigates the patterns of coattraction of items that appear in the two VP positions (the VP in the matrix clause, and the VP in the infinitive subordinate clause) in the English accusative...... relations of English accusatives-with-bare-infinitives through the relations of semantic coherence between the two VPs....

  6. Discovery Of Transient Iron Fluorescence In The Bare Seyfert Ark 120

    Science.gov (United States)

    Nardini, Emanuele; Porquet, D.; Reeves, J.; Braito, V.; Lobban, A.; Matt, G.

    2016-10-01

    We present the results from an X-ray observational campaign on the bare Seyfert galaxy Ark 120 jointly carried out with XMM- Newton, Chandra, and NuSTAR. The favourable line of sight to this source, devoid of any significant absorbing material, provides an incomparably clean view to the nuclear regions of an AGN, down to the the immediate surroundings of the radiatively efficient, accreting supermassive black hole. Here we focus on the nature, properties, and variability of the emission-line complex due to iron fluorescence detected in the 6-7 keV band. The narrow K-alpha feature from neutral iron at 6.4 keV is resolved by Chandra/HETG to a width of 5000 km/s, consistent with origin from the optical broad-line region. However, excess components are seen on both sides of this core. The excess emission map computed over the 7.5 days of XMM-Newton monitoring and the following, time-resolved spectral analysis show that both the red and blue features are highly variable on timescales of 10-15 hours. Any explanation (orbiting hotspots, coronal clumps, disc instabilities) requires a highly dynamic, inhomogeneous disc/coronal system. These observations thus prove the unique potential of a bare source like Ark 120 to better understand the physics of the accretion disc/X-ray corona system in AGN.

  7. Phospholipid bilayer formation at a bare Si surface

    DEFF Research Database (Denmark)

    Gutberlet, T.; Steitz, R.; Fragneto, G.

    2004-01-01

    Neutron reflectivity was applied to monitor in situ the adsorption of small unilamellar phospholipid vesicles on a solid bare hydrophilic Si interface. The obtained reflectivity curves are consistent with the rupture and fusion model for the adsorption of phosphatidylcholine vesicles to solid...

  8. Het paracervicale block tijdens de baring

    NARCIS (Netherlands)

    P.K. Flu (Peter Kalev)

    1977-01-01

    textabstractDe baring is het enige fysiologische gebeuren dat met pijn gepaard gaat. Dit wordt reeds aangeduid door het Nederlandse woord 11wee" en equivalente woorden in vele andere talen (dolor, douleur, pains, Wehe e.a.). De pijn is aanvankelijk vooral gelocaliseerd in de onderbuik en onder in de

  9. BARE retrotransposons are translated and replicated via distinct RNA pools.

    Directory of Open Access Journals (Sweden)

    Wei Chang

    Full Text Available The replication of Long Terminal Repeat (LTR retrotransposons, which can constitute over 80% of higher plant genomes, resembles that of retroviruses. A major question for retrotransposons and retroviruses is how the two conflicting roles of their transcripts, in translation and reverse transcription, are balanced. Here, we show that the BARE retrotransposon, despite its organization into just one open reading frame, produces three distinct classes of transcripts. One is capped, polyadenylated, and translated, but cannot be copied into cDNA. The second is not capped or polyadenylated, but is destined for packaging and ultimate reverse transcription. The third class is capped, polyadenylated, and spliced to favor production of a subgenomic RNA encoding only Gag, the protein forming virus-like particles. Moreover, the BARE2 subfamily, which cannot synthesize Gag and is parasitic on BARE1, does not produce the spliced sub-genomic RNA for translation but does make the replication competent transcripts, which are packaged into BARE1 particles. To our knowledge, this is first demonstration of distinct RNA pools for translation and transcription for any retrotransposon.

  10. Basic science of nuclear medicine the bare bone essentials

    CERN Document Server

    Lee, Kai H

    2015-01-01

    Through concise, straightforward explanations and supporting graphics that bring abstract concepts to life, the new Basic Science of Nuclear Medicine—the Bare Bone Essentials is an ideal tool for nuclear medicine technologist students and nuclear cardiology fellows looking for an introduction to the fundamentals of the physics and technologies of modern day nuclear medicine.

  11. 北京市平谷应急水源地周边农业土壤中重金属分布及风险评价%Distribution and Ecological Risk Assessment of Heavy Metals in Agricultural Soils Surrounding a Contingency Water Source, Beijing

    Institute of Scientific and Technical Information of China (English)

    唐磊; 张会昌; 季宏兵; 冯金国; 姚俊; 闫广新

    2015-01-01

    采用ArcGIS空间分析技术和多元统计方法研究了北京市平谷应急水源地周边农业土壤中重金属空间分布及来源,并基于潜在生态危害指数法进行了生态风险评价。结果表明,土壤中重金属含量均值由大到小为Mn﹥Pb﹥Cr﹥As﹥Hg﹥Cd,所有重金属含量均值都高于北京市土壤背景值。Pb、Cd和As污染较为严重,含量均值分别为96.78、0.25、28.40 mg·kg-1,且主要是人为来源;Mn和Cr元素平均含量稍高于北京市土壤背景值,主要来源为自然源;Hg元素的平均含量也稍高于北京市土壤背景值,是自然源和人为源共同作用的结果。重金属元素单项污染潜在生态风险系数从大到小依次为Cd﹥Hg﹥As﹥Pb﹥Cr﹥Mn,6种重金属综合潜在生态风险指数RI值为169.29,为中等生态危害,东南方向土壤重金属生态危害高于西北方向。综上所述,该水源地的土壤已经受到重金属的潜在威胁,其生态风险不容忽视。%Heavy metals in soils surrounding water source area pose direct risks to the water safety. Here the spatial distribution and sources of heavy metals in agricultural soils around a contingency water source of Pinggu, Beijing, were elucidated by ArcGIS and multivariate anal-ysis. The ecological risk assessment of soil heavy metals was also performed using potential ecological risk index(RI). The mean concentra-tions of heavy metals in soils were in order of [Mn]﹥[Pb]﹥[Cr]﹥[As]﹥[Hg]﹥[Cd], all exceeding the soil background values of Beijing. The soils were seriously polluted by Pb, Cd and As, with the mean concentrations of 96.78, 0.25 and 28.40 mg·kg-1, respectively. These metals mainly came from the human activities via mineral exploitation and transportation. The concentrations of Mn, Cr and Hg were slightly higher than the soil background values. Manganese and Cr were derived from the natural sources by weathering of rock and soil parent materials

  12. Plant Cover and Soil Biochemical Properties in a Mine Tailing Pond Five Years After Application of Marble Wastes and Organic Amendments

    Institute of Scientific and Technical Information of China (English)

    R. ZORNOZA; A. FAZ; D. M. CARMONA; S. KABAS; S. MART(I)NEZ-MART(I)NEZ; J. A. ACOSTA

    2012-01-01

    Tailing ponds pose environmental hazards,such as toxic metals which can contaminate the surroundings through wind and water erosions and leaching.Various chemical and biochemical properties,together with extractable and soluble metals were measured five years after reclamation of a polluted soil affected by former mining activities.This abandoned mine site contains large amounts of Fe-oxyhydroxides,sulphates,and heavy metals.As a consequence,soils remain bare and the soil organic matter content is low (< 3 g kg-1).Marble waste,pig manure and sewage sludge were applied in 2004.Plant cover and richness,and soil chemical,biochemical and biological parameters were analysed five years later.Results showed that all soil biochemical properties as well as vegetation cover and richness were higher in treated soils than in the untreated contaminated plots (control),although organic matter,pH values and extractable metals concentrations were similar among treatments.Soluble cadmium and zinc were lower in the amended plots than in control.As a general pattern,soil amended with pig manure showed higher values of most biochemical properties compared to sewage sludge application,while the doses did not have a great effect,being only significant for β-glucosidase,phosphodiesterase and arylsulfatase.Significant correlations were found between vegetation cover,richness and soil biochemical properties,suggesting a high interdependence between plant colonization and reactivation of biogeochemical cycles during five years.This study confirms the high effectiveness of an initial application of the amendments tested to initialize the recovery of ecosystems in bare mine soils under Mediterranean semiarid conditions. This research also shows the high sensitivity of certain biochemical properties in order to evaluate soil quality and reactivation of nutrients cycles in reclaimed mine soils.

  13. 黄土高原及周边地区土壤有机质对现代土壤磁化率的影响%Impact of soil organic matter on modern soil magnetic susceptibility in Loess Plateau and its surrounding areas

    Institute of Scientific and Technical Information of China (English)

    张博; 刘卫国

    2016-01-01

    Background, aim, and scope Magnetic susceptibility of soils can provide paleoclimatic information. In Chinese Loess Plateau, susceptibility enhancement is usually considered as a proxy of monsoon intensity. Several hypotheses were used to explain variations of this proxy. Here, we present a study on how soil magnetic susceptibility is related with soil organic matters. We analyzed magnetic susceptibility, organic carbon content, organic carbon isotopic composition, and C/N ratio of modern soils from Chinese Loess Plateau, in order to obtain the relationship between soil magnetic susceptibility and other parameters, as well as how soil organic matters affect soil magnetic susceptibility. Materials and methods Fifty modern soil samples were collected from the Loess Platform, forest areas at the Huangling and Huanglong Mount, and loess-desert area near the Tengger Desert. These soil samples represent modern soil types in the Loess Plateau. Samples were collected 2—3 cm below the surface. The sampling sites are at least 40 km away from any industrialized centers that could generate artificial, air-borne magnetic material. In this way, we minimized the effect of human and livestock activity. We tested magnetic susceptibility (χlf), organic carbon isotopic composition (δ13C), and organic carbon and nitrogen contents of these samples. Results The magnetic susceptibility varied from 26.6×10−8 m3∙kg−1 to 61.4×10−8 m3∙kg−1 for soils from the loess platform, and from 68.6×10−8 m3∙kg−1 to 107.5×10−8 m3∙kg−1 for soils from forest areas. The value of soil from forest areas is apparently higher than that from the loess platform. The magnetic susceptibility of soil samples from loess-desert area varied from 8.5×10−8 m3∙kg−1 to 44.4×10−8 m3∙kg−1.δ13C values of soil samples from the loess platform varied from−22‰to−24.4‰.δ13C values of soil samples from loess-desert area varied from−20.66‰to−24.69‰, whose range is

  14. Binaural Rendering in MPEG Surround

    Directory of Open Access Journals (Sweden)

    Kristofer Kjörling

    2008-04-01

    Full Text Available This paper describes novel methods for evoking a multichannel audio experience over stereo headphones. In contrast to the conventional convolution-based approach where, for example, five input channels are filtered using ten head-related transfer functions, the current approach is based on a parametric representation of the multichannel signal, along with either a parametric representation of the head-related transfer functions or a reduced set of head-related transfer functions. An audio scene with multiple virtual sound sources is represented by a mono or a stereo downmix signal of all sound source signals, accompanied by certain statistical (spatial properties. These statistical properties of the sound sources are either combined with statistical properties of head-related transfer functions to estimate “binaural parameters” that represent the perceptually relevant aspects of the auditory scene or used to create a limited set of combined head-related transfer functions that can be applied directly on the downmix signal. Subsequently, a binaural rendering stage reinstates the statistical properties of the sound sources by applying the estimated binaural parameters or the reduced set of combined head-related transfer functions directly on the downmix. If combined with parametric multichannel audio coders such as MPEG Surround, the proposed methods are advantageous over conventional methods in terms of perceived quality and computational complexity.

  15. Reduced surround inhibition in musicians.

    Science.gov (United States)

    Shin, Hae-Won; Kang, Suk Y; Hallett, Mark; Sohn, Young H

    2012-06-01

    To investigate whether surround inhibition (SI) in the motor system is altered in professional musicians, we performed a transcranial magnetic stimulation (TMS) study in 10 professional musicians and 15 age-matched healthy non-musicians. TMS was set to be triggered by self-initiated flexion of the index finger at different intervals ranging from 3 to 1,000 ms. Average motor evoked potential (MEP) amplitudes obtained from self-triggered TMS were normalized to average MEPs of the control TMS at rest and expressed as a percentage. Normalized MEP amplitudes of the abductor digiti minimi (ADM) muscles were compared between the musicians and non-musicians with the primary analysis being the intervals between 3 and 80 ms (during the movement). A mixed-design ANOVA revealed a significant difference in normalized ADM MEPs during the index finger flexion between groups, with less SI in the musicians. This study demonstrated that the functional operation of SI is less strong in musicians than non-musicians, perhaps due to practice of movement synergies involving both muscles. Reduced SI, however, could lead susceptible musicians to be prone to develop task-specific dystonia.

  16. Binaural Rendering in MPEG Surround

    Science.gov (United States)

    Breebaart, Jeroen; Villemoes, Lars; Kjörling, Kristofer

    2008-12-01

    This paper describes novel methods for evoking a multichannel audio experience over stereo headphones. In contrast to the conventional convolution-based approach where, for example, five input channels are filtered using ten head-related transfer functions, the current approach is based on a parametric representation of the multichannel signal, along with either a parametric representation of the head-related transfer functions or a reduced set of head-related transfer functions. An audio scene with multiple virtual sound sources is represented by a mono or a stereo downmix signal of all sound source signals, accompanied by certain statistical (spatial) properties. These statistical properties of the sound sources are either combined with statistical properties of head-related transfer functions to estimate "binaural parameters" that represent the perceptually relevant aspects of the auditory scene or used to create a limited set of combined head-related transfer functions that can be applied directly on the downmix signal. Subsequently, a binaural rendering stage reinstates the statistical properties of the sound sources by applying the estimated binaural parameters or the reduced set of combined head-related transfer functions directly on the downmix. If combined with parametric multichannel audio coders such as MPEG Surround, the proposed methods are advantageous over conventional methods in terms of perceived quality and computational complexity.

  17. Assembling Bare Au Nanoparticles at Positively Charged Templates

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Wenjie; Zhang, Honghu; Kuzmenko, Ivan; Mallapragada, Surya; Vaknin, David

    2016-05-26

    In-situ X-ray reflectivity (XRR) and grazing incidence X-ray small-angle scattering (GISAXS) reveal that unfunctionalized (bare) gold nanoparticles (AuNP) spontaneously adsorb to a cationic lipid template formed by a Langmuir monolayer of DPTAP (1,2-dihexadecanoyl-3-trimethylammonium-propane) at vapor/aqueous interfaces. Analysis of the XRR yields the electron density profile across the chargedinterfaces along the surface normal showing the AuNPs assemble with vertical thickness comparable to the particle size. The GISAXS analysis indicates that the adsorbed mono-particle layer exhibits shortrange in-plane correlations. By contrast, single-stranded DNA-functionalized AuNPs, while attracted to the positively charged surface (more efficiently with the addition of salt to the solution), display less in-plane regular packing compared to bare AuNPs.

  18. Low cost bare-plate solar air collector

    Energy Technology Data Exchange (ETDEWEB)

    Maag, W.L.; Wenzler, C.J.; Rom, F.E.; VanArsdale, D.R.

    1980-09-01

    The purpose of this project was to develop a low cost, bare-plate collector, determine its performance for a variety of climatic conditions, analyze the economics of this type of solar collector and evaluate specific applications. Two prototype collectors were designed, fabricated and installed into an instrumented test system. Tests were conducted for a period of five months. Results of the tests showed consistent operating efficiencies of 60% or greater with air preheat temperature uses up to 20/sup 0/F for one of the prototypes. The economic analyses indicated that an installed cost of between $5 and $10 per square foot would make this type of solar system economically viable. For the materials of construction and the type of fabrication and installation perceived, these costs for the bare-plate solar collector are believed to be attainable. Specific applications for preheating ventilation air for schools were evaluated and judged to be economically viable.

  19. Terrain classification of ladar data for bare earth determination

    Science.gov (United States)

    Neuenschwander, Amy L.; Magruder, Lori A.

    2011-06-01

    Terrain classification, or bare earth extraction, is an important component to LADAR data analysis. The terrain classification approach presented in this effort utilizes an adaptive lower envelope follower (ALEF) with an adaptive gradient operation for accommodations of local topography and roughness. In order to create a more robust capability, the ALEF was modified to become a strictly data driven process that facilitates a quick production of the data product without the subjective component associated with user inputs. This automated technique was tested on existing LADAR surveys over Wyoming's Powder River Basin and the John Starr Memorial Forest in Mississippi, both locations with dynamic topographic features. The results indicate a useful approach in terms of operational time and accuracy of the final bare earth recovery with the advantage of being fully data driven.

  20. Assembling Bare Au Nanoparticles at Positively Charged Templates

    Science.gov (United States)

    Wang, Wenjie; Zhang, Honghu; Kuzmenko, Ivan; Mallapragada, Surya; Vaknin, David

    2016-05-01

    In-situ X-ray reflectivity (XRR) and grazing incidence X-ray small-angle scattering (GISAXS) reveal that unfunctionalized (bare) gold nanoparticles (AuNP) spontaneously adsorb to a cationic lipid template formed by a Langmuir monolayer of DPTAP (1,2-dihexadecanoyl-3-trimethylammonium-propane) at vapor/aqueous interfaces. Analysis of the XRR yields the electron density profile across the charged-interfaces along the surface normal showing the AuNPs assemble with vertical thickness comparable to the particle size. The GISAXS analysis indicates that the adsorbed mono-particle layer exhibits short-range in-plane correlations. By contrast, single-stranded DNA-functionalized AuNPs, while attracted to the positively charged surface (more efficiently with the addition of salt to the solution), display less in-plane regular packing compared to bare AuNPs.

  1. Nuda vida y goce. // Bare life and jouissance.

    OpenAIRE

    Laura Arias.

    2010-01-01

    From the point of view that connects politics and psychoanalysis, the aim of this essay is to investigate the causes of the annihilation of the subject in the totalitarian regimes, making him a victim of power, reduced to a bare life. This question leads us to analyze the jouissance within the frame of a regime that proposes the unification of a universal jouissance. These questions are considered to be relevant in the field that makes possible the intersection between politics and subjectivi...

  2. The Political Animal: Species-Being and Bare Life

    Directory of Open Access Journals (Sweden)

    Laura Hudson

    2008-01-01

    Full Text Available Marxism has been justifiably skeptical of animal rights. Indeed, deep ecology and animal-rights discourse are, in their native habitats, deeply problematic and self-contradictory. But recent theories of “bare life,” when brought into dialogue with Marx’s concept of species-being, offer a perspective from which animal rights discourse and Marxism share a common political horizon.

  3. Bare-Hand Volume Cracker for Raw Volume Data Analysis

    Directory of Open Access Journals (Sweden)

    Bireswar Laha

    2016-09-01

    Full Text Available Analysis of raw volume data generated from different scanning technologies faces a variety of challenges, related to search, pattern recognition, spatial understanding, quantitative estimation, and shape description. In a previous study, we found that the Volume Cracker (VC 3D interaction (3DI technique mitigated some of these problems, but this result was from a tethered glove-based system with users analyzing simulated data. Here, we redesigned the VC by using untethered bare-hand interaction with real volume datasets, with a broader aim of adoption of this technique in research labs. We developed symmetric and asymmetric interfaces for the Bare-Hand Volume Cracker (BHVC through design iterations with a biomechanics scientist. We evaluated our asymmetric BHVC technique against standard 2D and widely used 3D interaction techniques with experts analyzing scanned beetle datasets. We found that our BHVC design significantly outperformed the other two techniques. This study contributes a practical 3DI design for scientists, documents lessons learned while redesigning for bare-hand trackers, and provides evidence suggesting that 3D interaction could improve volume data analysis for a variety of visual analysis tasks. Our contribution is in the realm of 3D user interfaces tightly integrated with visualization, for improving the effectiveness of visual analysis of volume datasets. Based on our experience, we also provide some insights into hardware-agnostic principles for design of effective interaction techniques.

  4. Effects of vegetation coverage on the spatial distribution of soil nematode trophic groups

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The spatial variability of total soil nematodes and trophic groups in bare and fallow plots in Shenyang Experi-mental Station of Ecology, Chinese Academy of Sciences was examined using geostatistics combined with classic statistics. Results showed that the soil pH value had a negative effect on plant-parasites in both bare and fallow plots; the mean number of total nematodes was significantly higher in fallow plots than in bare plots, which was 1485.3 and 464.0 individuals per 100 g dry soil in fallow and bare plots, respectively; the nugget (C0)/sill (C0+C) ratio of total nematodes, plant-parasites and bacterivores were lower in fallow plots (27.3%-45.6%) than in bare plots (49.5%-100%); the spatial distribution of total nematodes and trophic groups was found to be different between fallow and bare plots, which indicated that vegetation coverage had an effect on soil nematodes.

  5. Mapping soil water content under sparse vegetation and changeable sky conditions: comparison of two thermal inertia approaches

    Science.gov (United States)

    Maltese, Antonino; Capodici, Fulvio; Ciraolo, Giuseppe; La Loggia, Goffredo

    2013-01-01

    A critical analysis of a thermal inertia approach to map surface soil water content on bare and sparsely vegetated soils by means of remotely sensed data is reported. The study area is an experimental field located in Barrax, Spain. In situ data were acquired within the Barrax 2011 research project. An advanced hyperspectral scanner airborne imager provides images in the visible/near-infrared and thermal infrared bands. Images were acquired both in day and night times by the Instituto Nacional de Técnica Aeroespacial between 12th and 13th of June 2011. The scene covers a corn irrigation pivot surrounded by bare soil, where a set of in situ data have been collected both previously and simultaneously to overpasses. To validate remotely sensed estimations, an ad hoc dataset has been produced by measuring spectra, radiometric temperatures, surface soil water content, and soil thermal properties. These data were collected on two transects covering bare and sparsely vegetated soils. This ground dataset was used (1) to verify if a thermal inertia method can be applied to map the water content on soil covered by sparse vegetation and (2) to quantify a correction factor accounting for solar radiation reduction due to sky cloudiness. The experiment intended to test a spatially constant and a spatially distributed approach to estimate the phase difference. Both methods were then applied to the airborne images collected during the following days to obtain the spatial distribution of surface soil water content. Results confirm that the thermal inertia method can be applied to sparsely vegetated soil characterized by low fractional cover if the solar radiation reaching the ground is accurately estimated. A spatially constant value of the phase difference allows a good assessment of thermal inertia, whereas the comparison with the three-temperature approach did not give conclusive responses. Results also show that clear sky, only at the time of the acquisition, does not provide

  6. Impacts of grass removal on wetting and actual water repellency in a sandy soil

    National Research Council Canada - National Science Library

    Klaas Oostindie; Louis W. Dekker; Jan G. Wesseling; Violette Geissen; Coen J. Ritsema

    2017-01-01

    Soil water content and actual water repellency were assessed for soil profiles at two sites in a bare and grasscovered plot of a sand pasture, to investigate the impact of the grass removal on both properties...

  7. Geoquímica de radionuclídeos naturais em solos de áreas circunvizinhas a uma Unidade de Mineração e Atividade de Urânio Geochemistry of natural radionuclide in soils surrounding a Mining and Plant Uranium Concentration

    Directory of Open Access Journals (Sweden)

    Gildevan Viana Cardoso

    2009-12-01

    Full Text Available Os impactos ambientais advindos da exploração e do beneficiamento de U são, em grande parte, idênticos àqueles causados por atividades minero-extrativistas em geral. Este trabalho teve o objetivo de determinar a partição geoquímica dos radionuclídeos naturais 238U, 226Ra e 210Pb em áreas circunvizinhas à Unidade de Mineração e Atividade de Urânio (URA das Indústrias Nucleares do Brasil S.A., localizada na Província Uranífera de Lagoa Real, no município de Caetité, na região sudoeste do Estado da Bahia. Foram coletadas amostras de solo em cinco áreas circunvizinhas à URA, representando as principais classes de solos da região, na profundidade de 0-20 cm. Nas cinco áreas, foram determinados o teor de atividade total e o fracionamento geoquímico nas frações: F1 - levemente ácida, F2 - reduzível, F3 - oxidável, F4 - alcalina e F5 - residual. As atividades totais médias foram, em Bq kg-1 de solo, de 50 para 238U, 51 para 226Ra e 159 para 210Pb. Os extraídos na fase potencialmente biodisponível (F1 foram: 11 % para 238U, 13 % para 226Ra e 3 % para 210Pb. O 238U apresentou maior biodisponibilidade nos solos mais ácidos e maior afinidade pelos óxidos de Fe, o que não ocorreu para o 226Ra, tendo este apresentado a maior biodisponibilidade. O 210Pb apresentouse predominantemente associado a F5. As percentagens elevadas de 238U, 226Ra e 210Pb na fração geoquímica F5 indicam que as atividades observadas nos cinco solos estão, predominantemente, associadas ao material que deu origem a esses solos, e não a um processo de contaminação artificial em função da atividade da URA.The environmental impacts resulting from uranium exploration and processing are to a great extent identical to those caused by extractive mining activities in general. This study aimed to determine the geochemical partitioning of the natural radionuclides 238U, 226Ra and 210Pb in areas surrounding the Uranium Mining and Concentration Plant (URA

  8. Nitrogen losses in vineyards under different types of soil groundcover. A field runoff simulator approach in central Spain

    NARCIS (Netherlands)

    García-Díaz, Andrés; Bienes, Ramón; Sastre, Blanca; Novara, Agata; Gristina, Luciano; Cerda Bolinches, Artemio

    2017-01-01

    The soils of Mediterranean vineyards are usually managed with continuous tillage, resulting in bare soil, low infiltration and high soil erosion rates. Soil nutrients, such as nitrogen, could be lost dissolved in the runoff, causing a decrease in soil fertility on such degraded soils and producing e

  9. 30 CFR 56.12066 - Guarding trolley wires and bare powerlines.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Guarding trolley wires and bare powerlines. 56... Electricity § 56.12066 Guarding trolley wires and bare powerlines. Where metallic tools or equipment can come in contact with trolley wires or bare powerlines, the lines shall be guarded or deenergized. ...

  10. 30 CFR 57.12066 - Guarding trolley wires and bare powerlines.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Guarding trolley wires and bare powerlines. 57... MINES Electricity Surface Only § 57.12066 Guarding trolley wires and bare powerlines. Where metallic tools or equipment can come in contact with trolley wires or bare powerlines, the lines shall be guarded...

  11. 30 CFR 77.515 - Bare signal or control wires; voltage.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Bare signal or control wires; voltage. 77.515... COAL MINES Electrical Equipment-General § 77.515 Bare signal or control wires; voltage. The voltage on bare signal or control wires accessible to personal contact shall not exceed 40 volts. ...

  12. Supersonic Bare Metal Cluster Beams. Technical Progress Report, March 16, 1984 - April 1, 1985

    Science.gov (United States)

    Smalley, R. E.

    1985-01-01

    There have been four major areas of concentration for the study of bare metal cluster beams: neutral cluster, chemical reactivity, cold cluster ion source development (both positive and negative), bare cluster ion ICR (ion cyclotron resonance) development, and photofragmentation studies of bare metal cluster ions.

  13. 30 CFR 75.517-2 - Plans for insulation of existing bare power wires and cables.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Plans for insulation of existing bare power... Equipment-General § 75.517-2 Plans for insulation of existing bare power wires and cables. (a) On or before December 31, 1970, plans for the insulation of existing bare power wires and cables installed prior to...

  14. Soil CO 2 Flux in Hövsgöl National Park, Northern Mongolia

    Directory of Open Access Journals (Sweden)

    Avirmed Otgonsuren

    2008-06-01

    Full Text Available We investigated soil CO 2 fl ux and bare soil respiration in grasslands that are located at the southern edge of the Siberian boreal forest in Northern Mongolia. The study area has warmed by almost 1.8 o C over the last 40 years, and the soil and vegetation covers have been changed due to intense nomadic grazing pressure. Bare soil respiration is decreased with increasing grazing pressure, but there was no consistent pattern of total soil CO 2 fl ux under three distinct grazing levels. Bare soil respiration and soil CO 2 fl ux were higher on north-facing slopes than on south-facing slopes, due to high organic matter accumulation and the presence of permafrost. Both bare soil respiration and soil CO 2 fl ux were signi fi cantly higher in riparian areas compared with the lower and upper portions of the south-facing slope. Topography has a stronger effect on variability of soil CO 2 fl ux and bare soil respiration than variability induced by grazing. Inter-annual variability in soil CO 2 fl ux and bare soil respiration was very high, because of high variability in climate conditions.

  15. Effect of rain enrichment on soil respiration of Nitraria sphaerocarpa community in a hyperarid area

    Institute of Scientific and Technical Information of China (English)

    DianJun Liu; Bo Wu; YongHua Li; GuangHui Lin; ShiPing Chen; YaJuan Zhu; Qi Lu; Bin Yao

    2013-01-01

    In order to analyze the effect of rain enrichment on soil respiration rate of a Nitraria sphaerocarpa community, we measured soil respiration rate in bare and vegetated areas in a hyperarid area (Dunhuang) during the growing season. Results show that rain enrichment can increase bare and vegetated soil respiration rates. The more rainfall enrichment, the greater the increment and the longer duration time effect for soil respiration rate. 200%(16 mm) and 300%(24 mm) of rain enrichment can significantly increase bare soil respiration rates by 90%and 106%(P<0.01), respectively. By contrast, areas with 100%(8 mm), 200%(16 mm) and 300% (24 mm) of rain enrichment can significantly increase shrub area respiration rates by 68%, 157%and 205%(P<0.01), respectively. The response time of bare and vegetated soil respiration to rainfall enrichment is asynchronous. Response variable of soil respiration in vegetated soil is higher (118%) than in bare soil. There was significant positive correlation between soil respiration rate and soil water content during the growing season (P<0.01). For every 1 mm increment of precipitation, soil respiration rate increased by 0.01 and 0.04μmol/(m2·s), respectively in vegetated and bare soils.

  16. Wave energy resource in the Estaca de Bares area (Spain)

    Energy Technology Data Exchange (ETDEWEB)

    Iglesias, G.; Carballo, R. [Univ. of Santiago de Compostela, EPS, Hydraulic Eng., Campus Univ. s/n, 27002 Lugo (Spain)

    2010-07-15

    The area around Cape Estaca de Bares (the northernmost point of Iberia) presents a great potential for wave energy exploitation owing to its prominent position, with average deepwater wave power values exceeding 40 kW/m. The newly available SIMAR-44 dataset, composed of hindcast data spanning 44 years (1958-2001), is used alongside wave buoy data and numerical modelling to assess this substantial energy resource in detail. Most of the energy is provided by waves from the IV quadrant, generated by the prevailing westerlies blowing over the long Atlantic fetch. Combined scatter and energy diagrams are used to characterise the wave energy available in an average year in terms of the sea states involved. The lion's share is shown to correspond to significant wave heights between 2 and 5 m and energy periods between 11 and 14 s. The nearshore energy patterns are then examined using a coastal wave model (SWAN) with reference to four situations: average wave energy, growing wave energy (at the approach of a storm), extreme wave energy (at the peak of the storm) and decaying wave energy (as the storm recedes). The irregular bathymetry is found to produce local concentrations of wave energy in the nearshore between Cape Prior and Cape Ortegal and in front of Cape Estaca de Bares, with similar patterns (but varying wave power) in the four cases. These nearshore areas of enhanced wave energy are of the highest interest as prospective sites for a wave energy operation. The largest of them is directly in the lee of a large underwater mount west of Cape Ortegal. In sum, the Estaca de Bares area emerges as one of the most promising for wave energy exploitation in Europe. (author)

  17. Rethinking biopower: posthumanism, bare life, and emancipatory work.

    Science.gov (United States)

    Cloyes, Kristin G

    2010-01-01

    This article answers a call, recently published in Advances in Nursing Science, to more fully explore the use of Italian political philosopher Giorgio Agamben's theory of biopower in nursing research and scholarship. Giorgio Agamben argues that biopower is not a modern phenomenon, and critical analysis of the historical origins of Western political practice shows how humanist discourse has been complicit in a long tradition of marginalization and violence, accomplished in each era by designating certain classes of human beings as "bare life." I discuss how I have used Agamben's theory to frame my own research, and the challenges of applying this theory in emancipatory work.

  18. Phospholipid bilayer formation at a bare Si surface

    DEFF Research Database (Denmark)

    Gutberlet, T.; Steitz, R.; Fragneto, G.;

    2004-01-01

    Neutron reflectivity was applied to monitor in situ the adsorption of small unilamellar phospholipid vesicles on a solid bare hydrophilic Si interface. The obtained reflectivity curves are consistent with the rupture and fusion model for the adsorption of phosphatidylcholine vesicles to solid...... interfaces. The results show details of the adsorbed bilayer system at ångström resolution and indicate the presence of a thin ∼6 Å thick water leaflet that separates the bilayer from the Si surface. The resolved structural details provide the basis for further investigation of processes such as adsorption...

  19. 江西铜矿及冶炼厂周边土壤和农作物稀土元素含量与评价%Rare Earth Elements Content in Farmland Soils and Crops of the Surrounding Copper Mining and Smelting Plant in Jiangxi Province and Evaluation of Its Ecological RisK

    Institute of Scientific and Technical Information of China (English)

    金姝兰; 向猛; 黄益宗; 王斐; 徐峰; 王小玲; 高柱; 胡莹; 乔敏; 李季

    2015-01-01

    研究江西省铜矿开采和冶炼对周边农田土壤、农作物稀土元素含量的影响.结果表明,铜矿开采和冶炼可提高土壤及农作物稀土元素的含量.德兴银山铅锌铜矿和贵溪冶炼厂周边农田土壤中总稀土元素含量范围分别为112.42~397.02 mg·kg-1和48.81~250.06 mg·kg-1,总稀土元素平均值分别为254.84 mg·kg-1和144.21 mg·kg-1,分别是江西省背景值的1.21倍和0.68倍,全国背景值的1.36倍和0.77倍,对照样点的3.59倍和2.03倍.贵溪冶炼厂周边10种农作物样品中总稀土元素含量范围为0.35~2.87 mg·kg-1,作物叶子中的稀土元素含量高于茎和块根.番茄、空心菜叶和萝卜叶中总稀土元素含量分别为2.87、1.58和0.80 mg·kg-1,均超过我国蔬菜和水果卫生标准的总稀土元素含量限值(0.70 mg·kg-1).矿区居民终身摄入稀土元素的总量为17.72μg·( kg·d)-1,低于安全剂量和临界值,对人体还不构成健康风险.研究结果说明在江西进行铜矿开采和冶炼时必须重视稀土元素对周边环境的影响.%Rare earth elements content in farmland soils and crops of the surrounding copper mining and smelting plant in Jiangxi province was studied. The results showed that copper mining and smelting could increase the content of rare earth elements in soils and crops. Rare earth elements content in farmland soils of the surrounding Yinshan Lead Zinc Copper Mine and Guixi Smelting Plant varied from 112. 42 to 397. 02 mg·kg -1 and 48. 81 to 250. 06 mg·kg-1 , and the average content was 254. 84 mg · kg -1 and 144. 21 mg·kg-1 , respectively. The average contents of rare earth elements in soils in these two areas were 1. 21 times and 0. 68 times of the background value in Jiangxi province, 1. 36 times and 0. 77 times of the domestic background value, 3. 59 times and 2. 03 times of the control samples, respectively. Rare earth elements content in 10 crops of the surrounding Guixi Smelting Plant varied from 0. 35

  20. Military installation sequestered more carbon than surrounding areas

    Science.gov (United States)

    Zhao, S.; Liu, S.; Li, Z.; Sohl, T.

    2008-12-01

    Land use activities greatly affect the temporal trends and spatial patterns of regional land-atmospheric exchange of carbon. Military installations generally have drastically different land management strategies from surrounding areas, and the carbon consequences have never been quantified and assessed. Here, we used the General Ensemble Biogeochemical Modeling System (GEMS) to simulate and compare ecosystem carbon dynamics between Fort Benning and surrounding areas from 1992 to 2050. GEMS was driven by unique combinations of spatial and temporal dynamics of major driving forces, such as climate, soil properties, nitrogen deposition, and land use and land cover changes (predicted by FOREcasting SCEnarios of land cover change (FORE-SCE)). Our results indicated that the military installation sequestered more carbon than surrounding areas (0.77 vs. 0.16 Mg C ha-1 y-1 averaged from 1992 to 2007). Differences in land use activities were the primary cause behind the difference in carbon sequestration rates. From 1992 to 2007, no urban/residential expansion occurred at the installation, and transitional barren (primarily caused by forest harvesting) slightly increased from 0 to 0.2%. In contrast, urban land increased from 5.6 to 7.6% and transitional barren increased from 0.1 to 0.7% in the surrounding areas. Live biomass accumulation accounted for most of the carbon sink in both Fort Benning and surrounding areas (0.75 vs. 0.15 Mg C ha-1 y-1), while soil organic carbon accumulation was small (0.02 vs. 0.01 Mg C ha- 1 y-1), suggesting biomass removal caused by urbanization and harvesting resulted in much less carbon sequestration in surrounding areas. Fort Benning is likely to sequester more carbon in the future, although the rate of carbon sequestered per year will gradually reduce. The future carbon source/sink strength in the surrounding areas varied greatly, from a small sink to a strong source, depending on the path of land use change (e.g., increase of clear

  1. Application of multispectral remote sensing to soil survey research in Indiana

    Science.gov (United States)

    Zachary, A. L.; Cipra, J. E.; Diderickson, R. I.; Kristof, S. J.; Baumgardner, M. F.

    1972-01-01

    Computer-implemented mappings based on spectral properties of bare soil surfaces were compared with mapping units of interest to soil surveyors. Some soil types could be differentiated by their spectral properties. In other cases, soils with similar surface colors and textures could not be distinguished spectrally. The spectral maps seemed useful for delineating boundaries between soils in many cases.

  2. Bare ground as a crucial habitat feature for a rare terrestrially foraging farmland bird of Central Europe

    Science.gov (United States)

    Tagmann-Ioset, Aline; Schaub, Michael; Reichlin, Thomas S.; Weisshaupt, Nadja; Arlettaz, Raphaël

    2012-02-01

    Most farmland birds have declined significantly throughout the world due to agricultural intensification. Agri-environmental policies could not halt the decline of ground-foraging insectivorous farmland birds in Europe, indicating a gap in knowledge of species' ecological requirements. This represents a major impediment to the development of efficient, evidence-based agri-environmental measures. Using radio-tracking we studied habitat selection by farmland Hoopoes, a rare terrestrially foraging bird in Central Europe, and assessed habitat preferences of their main prey (Molecrickets), with the aim to identify optimal foraging habitat profiles in order to guide farmland management. Hierarchical logistic regression modelling of habitat descriptors at actual foraging locations vs. random locations within the home ranges of 13 males showed that the availability of bare ground was the principal determinant of foraging activity, with an optimum of 60-70% bare ground at patch scale. This ideal habitat configuration, which facilitates birds' terrestrial hunting, was found primarily in intensively farmed fruit tree plantations which dominated the landscape matrix: this habitat offers extensive strips of bare ground due to systematic removal of ground vegetation along tree rows. In contrast, dense grassland and cropland were avoided. Another important habitat feature was the availability of nongravelly soil, which enabled Hoopoes to probe the earth with their long, curved bill in search of underground invertebrates. The role of Molecrickets, however, appeared secondary to foraging patch selection, suggesting that prey accessibility was per se more important than prey abundance. Creating patches of bare ground within modern farmland where sufficient supplies of suitable invertebrate prey exist will support Hoopoe populations.

  3. Bare-Bones Teaching-Learning-Based Optimization

    Directory of Open Access Journals (Sweden)

    Feng Zou

    2014-01-01

    Full Text Available Teaching-learning-based optimization (TLBO algorithm which simulates the teaching-learning process of the class room is one of the recently proposed swarm intelligent (SI algorithms. In this paper, a new TLBO variant called bare-bones teaching-learning-based optimization (BBTLBO is presented to solve the global optimization problems. In this method, each learner of teacher phase employs an interactive learning strategy, which is the hybridization of the learning strategy of teacher phase in the standard TLBO and Gaussian sampling learning based on neighborhood search, and each learner of learner phase employs the learning strategy of learner phase in the standard TLBO or the new neighborhood search strategy. To verify the performance of our approaches, 20 benchmark functions and two real-world problems are utilized. Conducted experiments can been observed that the BBTLBO performs significantly better than, or at least comparable to, TLBO and some existing bare-bones algorithms. The results indicate that the proposed algorithm is competitive to some other optimization algorithms.

  4. High-performance, bare silver nanowire network transparent heaters.

    Science.gov (United States)

    Ergun, Orcun; Coskun, Sahin; Yusufoglu, Yusuf; Unalan, Husnu Emrah

    2016-11-04

    Silver nanowire (Ag NW) networks are one of the most promising candidates for the replacement of indium tin oxide (ITO) thin films in many different applications. Recently, Ag-NW-based transparent heaters (THs) showed excellent heating performance. In order to overcome the instability issues of Ag NW networks, researchers have offered different hybrid structures. However, these approaches not only require extra processing, but also decrease the optical performance of Ag NW networks. So, it is important to investigate and determine the thermal performance limits of bare-Ag-NW-network-based THs. Herein, we report on the effect of NW density, contact geometry, applied bias, flexing and incremental bias application on the TH performance of Ag NW networks. Ag-NW-network-based THs with a sheet resistance and percentage transmittance of 4.3 Ω sq(-1) and 83.3%, respectively, and a NW density of 1.6 NW μm(-2) reached a maximum temperature of 275 °C under incremental bias application (5 V maximum). With this performance, our results provide a different perspective on bare-Ag-NW-network-based transparent heaters.

  5. Laser impingement on bare and encased high explosives: safety limits

    Energy Technology Data Exchange (ETDEWEB)

    Roeske, F

    1999-03-15

    During the course of experiments involving high explosives, (HE), alignment lasers are often employed where the laser beam impinges upon a metal encased HE sample or on the bare HE itself during manned operations. While most alignment lasers are of low enough power so as not to be of concern, safety questions arise when considering the maximum credible power output of the laser in a failure mode, or when multiple laser spots are focused onto the experiment simultaneously. Safety questions also arise when the focused laser spot size becomes very small, on the order of 100 {micro}m or less. This paper addresses these concerns by describing a methodology for determining safety margins for laser impingement on metal encased HE as well as one for bare HE. A variety of explosives encased in Al, Cu, Ta and stainless steel were tested using the first of these techniques. Additional experiments were performed using the second method where the laser beam was focused directly on eight different samples of pressed-powder HE.

  6. Bare Metal Stenting for Endovascular Exclusion of Aortic Arch Thrombi

    Energy Technology Data Exchange (ETDEWEB)

    Mahnken, Andreas H., E-mail: mahnken@med.uni-marburg.de [University Hospital Giessen and Marburg, Philipps University of Marburg, Department of Diagnostic Radiology (Germany); Hoffman, Andras; Autschbach, Ruediger; Damberg, Anneke L. M., E-mail: anneke.damberg@rwth-aachen.de [University Hospital RWTH Aachen, Department of Thoracic, Cardiac and Vascular Surgery (Germany)

    2013-08-01

    BackgroundAortic thrombi in the ascending aorta or aortic arch are rare but are associated with a relevant risk of major stroke or distal embolization. Although stent grafting is commonly used as a treatment option in the descending aorta, only a few case reports discuss stenting of the aortic arch for the treatment of a thrombus. The use of bare metal stents in this setting has not yet been described.MethodsWe report two cases of ascending and aortic arch thrombus that were treated by covering the thrombus with an uncovered stent. Both procedures were performed under local anesthesia via a femoral approach. A femoral cutdown was used in one case, and a total percutaneous insertion was possible in the second case.ResultsBoth procedures were successfully performed without any periprocedural complications. Postoperative recovery was uneventful. In both cases, no late complications or recurrent embolization occurred at midterm follow-up, and control CT angiography at 1 respectively 10 months revealed no stent migration, freely perfused supra-aortic branches, and no thrombus recurrence.ConclusionTreating symptomatic thrombi in the ascending aorta or aortic arch with a bare metal stent is feasible. This technique could constitute a minimally invasive alternative to a surgical intervention or complex endovascular therapy with fenestrated or branched stent grafts.

  7. Iron line profiles in Suzaku spectra of bare Seyfert galaxies

    CERN Document Server

    Patrick, A R; Porquet, D; Markowitz, A G; Lobban, A P; Terashima, Y

    2010-01-01

    We methodically model the broad-band Suzaku spectra of a small sample of six 'bare' Seyfert galaxies: Ark 120, Fairall 9, MCG-02-14-009, Mrk 335, NGC 7469 and SWIFT J2127.4+5654. The analysis of bare Seyferts allows a consistent and physical modelling of AGN due to a weak amount of any intrinsic warm absorption, removing the degeneracy between the spectral curvature due to warm absorption and the red-wing of the Fe K region. Through effective modelling of the broad-band spectrum and investigating the presence of narrow neutral or ionized emission lines and reflection from distant material, we obtain an accurate and detailed description of the Fe K line region using models such as laor, kerrdisk and kerrconv. Results suggest that ionized emission lines at 6.7 keV and 6.97 keV (particularly Fe XXVI) are relatively common and the inclusion of these lines can greatly affect the parameters obtained with relativistic models i.e. spin, emissivity, inner radius of emission and inclination. Moderately broad components...

  8. Contour detection by surround suppression of texture

    NARCIS (Netherlands)

    Petkov, Nicolai; Tavares, JMRS; Jorge, RMN

    2007-01-01

    Based on a keynote lecture at Complmage 2006, Coimbra, Oct. 20-21, 2006, an overview is given of our activities in modelling and using surround inhibition for contour detection. The effect of suppression of a line or edge stimulus by similar surrounding stimuli is known from visual perception studie

  9. Heavy Metals Pollution and Eco-security Evaluation in the Surrounding Soil of An Untapped Lead-zinc Mining%一个未开采的铅锌矿周边土壤重金属含量及生态安全评价

    Institute of Scientific and Technical Information of China (English)

    张广胜; 徐文彬; 李俊翔; 韦金莲

    2015-01-01

    金属污染情况大不相同,该拟开采铅锌矿在其后续的开采、选矿活动中,应高度重视重金属污染的研究和防治,采取合理措施,防止加剧周边土壤的重金属累积。%In order to comprehand the content and potential ecological risk of haavy metals in the surrounding soil of Jianbidong lead-zinc mining in Fengshun Guangdong, adopting the methods of field sampling and laboratory analysis test, regarding four different surface soil areas as analyzing case studies, the heavy metal contents (Pb、Zn、Cu、Cd、Cr、As) of the surrounding surface soil from the lead-zinc mining were determined.The analyzing methodologies include single factor evaluation, Nemerow comprehensive index method, evaluation of Hakanson potential ecological risk assessment and health risk assessment so that to assess the level and potential ecological risk of heavy metals from the soil. The result shows that: under the undeveloped situation of this lead-zinc mining, the soil around the mining area has occourred somewhat pollution of heavy metals, and most of the soil samples with Pb(average of 106.77 mg·kg-1), Cd(average of 0.27 mg·kg-1), Zn(average 55.75 mg·kg-1) from the four research areas were over the background value of Guangdong Province;The polluted index shows Pb(maximum value of 4.57), Cd(maximum value of 2.98), Zn(maximum value of 1.41) pollutions are the most common;Comprehensive index shows polluted degree of the soil of Laohuge paddy field area is the most serious and the value is accounting 3.47. Meanwhile, the number of the soil samples which have medium degree of pollution is equal 51.02% of the number of the whole;While the Hakanson potential ecological risk assessment indicated that the mining potential ecological risk at low level, the four area of potential ecological risk index (RI) was less than 150, the average value was 110.67, probably due to the fact that the mine area were still undeveloped, and influence of human

  10. [Effects of different planting modes on the soil permeability of sloping farmlands in purple soil area].

    Science.gov (United States)

    Li, Jian-Xing; He, Bing-Hui; Mei, Xue-Mei; Liang, Yan-Ling; Xiong, Jian

    2013-03-01

    Taking bare land as the control, this paper studied the effects of different planting modes on the soil permeability of sloping farmlands in purple soil area. For the test six planting modes, the soil permeability was in the order of Eriobotrya japonica > Citrus limon > Vetiveria zizanioides hedgerows +corn >Leucaena leucocephala hedgerows + corn> Hemerocallis fulva > corn> bare land, and decreased with increasing depth. The eigenvalues of soil infiltration were in the order of initial infiltration rate> average infiltration rate> stable infiltration rate. The soil permeability had significant positive linear correlations with soil total porosity, non-capillary porosity, initial moisture content, water holding capacity, and organic matter content, and significant negative linear correlation with soil bulk density. The common empirical infiltration model could well fit the soil moisture infiltration processes under the six planting modes, while the Kostiakov equation could not.

  11. Critical analysis of the thermal inertia approach to map soil water content under sparse vegetation and changeable sky conditions

    Science.gov (United States)

    Maltese, Antonino; Capodici, Fulvio; Corbari, Chiara; Ciraolo, Giuseppe; La Loggia, Goffredo; Sobrino, José Antonio

    2012-09-01

    The paper reports a critical analysis of the thermal inertia approach to map surface soil water content on bare and sparsely vegetated soils by means of remotely sensed data. The study area is an experimental area located in Barrax (Spain). Field data were acquired within the Barrax 2011 research project. AHS airborne images including VIS/NIR and TIR bands were acquired both day and night time by the INTA (Instituto Nacional de Técnica Aeroespacial) between the 11th and 13rd of June 2011. Images cover a corn pivot surrounded by bare soil, where a set of in situ data have been collected previously and simultaneously to overpasses. To validate remotely sensed estimations, a preliminary proximity sensing set up has been arranged, measuring spectra and surface temperatures on transects by means of ASD hand-held spectroradiometer and an Everest Interscience radiometric thermometer respectively. These data were collected on two transects: the first one on bare soil and the second from bare to sparsely vegetated soil; soil water content in both transects ranged approximately between field and saturation values. Furthermore thermal inertia was measured using a KD2Pro probe, and surface water content of soil was measured using FDR and TDR probes. This ground dataset was used: 1) to verify if the thermal inertia method can be applied to map water content also on soil covered by sparse vegetation, and 2) to quantify a correction factor of the downwelling shortwave radiation taking into account sky cloudiness effects on thermal inertia assessment. The experiment tests both Xue and Cracknell approximation to retrieve the thermal inertia from a dumped value of the phase difference and the three-temperature approach of Sobrino to estimate the phase difference spatial distribution. Both methods were then applied on the remotely sensed airborne images collected during the following days, in order to obtain the spatial distribution of the surface soil moisture on bare soils and

  12. Corrosion of bare and galvanized steel in gypsum

    Directory of Open Access Journals (Sweden)

    Gómez, Mercedes

    1988-12-01

    Full Text Available Gypsum is a relatively low-cost building material much abounding in our country. When it is put in contact with steel, it may produce high corrosion rates due to its pH value (close to 7. This work reports the results obtained in studying the corrosion rates of bare and galvanized steel in contact with gypsum and plaster, as well as the influence curing thermal treatment applied to gypsum, enviromental relative humidity and addition of compounds with different natures and purposes may have in such process. In-situ observations, as well as the measurement of the Polarization Resistance and the weight loss have been used as measurement technics. From the results obtained it has been possible to deduce that galvanized steel has better behaviour in dry enviroments than bare steel in the same conditions and moist atmosphere induces proportionally more corrosion in galvanized steel than in bare one. Additions to gypsum do not modified these conclusions, though it may be pointed out that addition of nitrites or lime improves the behaviour of bare steel, while galvanized behaviour is not modified. The addition of lime is not recommended because phenomena of dilated along time expansion may take place.

    El yeso es un material de construcción de relativo bajo coste y que, además, es muy abundante en nuestro país. Debido a su pH cercano a la neutralidad, cuando entra en contacto con el acero, este puede corroerse a elevadas velocidades. En esta comunicación se presentan los resultados de un estudio sobre la velocidad de corrosión del acero desnudo y galvanizado en contacto con yeso y escayola y la influencia que tienen: el tratamiento térmico del curado del yeso, la humedad relativa ambiental y la adición de aditivos de diversa naturaleza y finalidad. Como técnicas de medida se han utilizado la medida de la Resistencia de Polarización y de la pérdida de peso, así como observaciones visuales. De los resultados se puede deducir que en

  13. Achievement of a superpolish on bare stainless steel

    Science.gov (United States)

    Howells, Malcolm R.; Casstevens, John M.

    1997-11-01

    We report the achievement of a superpolished surface, suitable for x-ray reflection, on bare stainless steel. The rms roughness obtained on various samples varied from 2.2 to 4.2 angstroms, as measured by an optical profiler with a bandwidth 0.29 - 100 mm-1. The type 17-4 PH precipitation-hardening stainless steel used to make the mirrors is also capable of ultrastability and has good manufacturability. This combination of properties makes it an excellent candidate material for mirror substrates. We describe the successful utilization of this type of steel in making elliptical-cylinder mirrors for a soft-x-ray microprobe system at the Advanced Light Source, and discuss possible reasons for its unusual stability and polishability.

  14. Radiative Capture of Twisted Electrons by Bare Ions

    CERN Document Server

    Matula, Oliver; Serbo, Valeriy G; Surzhykov, Andrey; Fritzsche, Stephan

    2014-01-01

    Recent advances in the production of twisted electron beams with a subnanometer spot size offer unique opportunities to explore the role of orbital angular momentum (OAM) in basic atomic processes. In the present work, we address one of these processes: radiative recombination of twisted electrons with bare ions. Based on the density matrix formalism and the non-relativistic Schr\\"odinger theory, analytical expressions are derived for the angular distribution and the linear polarization of photons emitted due to the capture of twisted electrons into the ground state of (hydrogen-like) ions. We show that these angular and polarization distributions are sensitive to both, the transverse momentum and the topological charge of the electron beam. To observe in particular the value of this charge, we propose an experiment that makes use of the coherent superposition of two twisted beams.

  15. Interaction of Hg Atom with Bare Si(111) Surface

    Institute of Scientific and Technical Information of China (English)

    LIU Yong-Jun; LIU Ying

    2006-01-01

    To evaluate the interaction between Hg atom and bare Si(111) surface, three types of silicon cluster models of Si4H7, Si7H10 and Si16H20 together with their Hg complexes were studied by using hybrid (U)B3LYP density functional theory method. Optimized geometries and energies for Hg atom on different adsorption sites indicate that: 1) the binding energies at different adsorption sites are small (ranging from ~3 to 8 kJ/mol dependent on the adsorption sites), suggesting a weak interaction between Hg atom and silicon surface; 2) the most favorable adsorption site is the on top (T) site. By analyzing their natural bonding orbitals, the possible reason of this difference is suggested.

  16. Bird community in an Araucaria forest fragment in relation to changes in the surrounding landscape in Southern Brazil

    Directory of Open Access Journals (Sweden)

    Pedro Scherer-Neto

    2012-12-01

    Full Text Available The dynamics of the bird community in a small forest fragment was evaluated along seven years in relation to changes in the surrounding landscape. The study area is an Araucaria forest fragment in Southern Brazil (state of Paraná. The sampling period covered the years 1988 through 1994 and the mark-release-recapture method was utilized. The landscape analysis was based on Landsat TM images, and changes in exotic tree plantations, native forest, open areas (agriculture, pasture, bare soil, and abandoned field, and "capoeira"(native vegetation < 2 m were quantified. The relationship between landscape changes and changes in abundance diversity of forest birds, open-area birds, forest-edge birds, and bamboo specialists was evaluated. Richness estimates were run for each year studied. The richness recorded in the study area comprised 96 species. The richness estimates were 114, 118 and 110 species for Chao 1, Jackknife 1 and Bootstrap, respectively. The bird community varied in species richness, abundance and diversity from year to year. As for species diversity, 1991, 1993 and 1994 were significantly different from the other years. Changes in the landscape contributed to the increase in abundance and richness for the groups of forest, open-area and bamboo-specialist species. An important factor discussed was the effect of the flowering of "taquara" (Poaceae, which contributed significantly to increasing richness of bamboo seed eaters, mainly in 1992 and 1993. In general, the results showed that landscape changes affected the dynamics and structure of the bird community of this forest fragment over time, and proved to have an important role in conservation of the avian community in areas of intensive forestry and agricultural activities.

  17. SPOT5 imagery for soil salinity assessment in Iraq

    Science.gov (United States)

    Teggi, S.; Costanzini, S.; Despini, F.; Chiodi, P.; Immordino, F.

    2012-10-01

    Soil salinization is a form of topsoil degradation due to the formation of soluble salts at deleterious levels. This phenomenon can seriously compromise vegetation health and agricultural productivity, and represents a worldwide environmental problem. Remote sensing is a very useful tool for soil salinization monitoring and assessment. In this work we show some results of a study aimed to define a methodology for soil salinity assessment in Iraq based on SPOT 5 imagery. This methodology allows the identification of salinized soils primarily on bare soils. Subsequently some soil salinity assessment can be done on vegetated soils. On bare soil the identification of salt is based on spectral analysis, using the Minimum Noise Fraction transformation and several indexes found in literature. In case of densely vegetated soils the methodology for the discrimination of salinized soils has been integrated with the results obtained from the classification of vegetation coverage.

  18. Field-measured, hourly soil water evaporation stages in relation to reference evapotranspiration rate and soil to air temperature ratio

    Science.gov (United States)

    Soil water evaporation takes critical water supplies away from crops, especially in areas where both rainfall and irrigation water are limited. This study measured bare soil water evaporation from clay loam, silt loam, sandy loam, and fine sand soils. It found that on average almost half of the ir...

  19. Bacterial Community Structure in a Mollisol Under Long-Term Natural Restoration, Cropping, and Bare Fallow History Estimated by PCR-DGGE

    Institute of Scientific and Technical Information of China (English)

    WANG Guang-Hua; JIN Jian; LIU Jun-Jie; CHEN Xue-Li; LIU Ju-Dong; LIU Xiao-Bing

    2009-01-01

    Soil microbial biomass and community structures are commonly used as indicators for soil quality and fertility.A investigation was performed to study the effects of long-term natural restoration,cropping,and bare fallow managements on the soil microbial biomass and bacterial community structures in depths of 0-10,20-30,and 40-50 cm in a black soil (Mollisol).Microbial biomass was estimated from chloroform fumigation-extraction,and bacterial community structures were determined by analysis of 16S rDNA using polymerase chain reaction-denaturing gradient gel electrophoresis (PCRDGGE).Experimental results showed that microbial biomass significantly declined with soil depth in the managements of restoration and cropping,but not in the bare fallow.DGGE profiles indicated that the band number in top 0-10 cm soils was less than that in depth of 20-30 or 40-50 cm.These suggested that the microbial population was high but the bacterial community structure was simple in the topsoil.Cluster and principle component analysis based on DGGE banding patterns showed that the bacterial community structure was affected by soil depth more primarily than by managements,and the succession of bacterial community as increase of soil depth has a similar tendency in the three managements.Fourteen predominating DGGE bands were excised and sequenced,in which 6 bands were identified as the taxa of Verrucomicrobia,2 bands as Actinobacteria,2 bands as α-Proteobacteria,and the other 4 bands as δ-Proteobacteria,Acidobacteria,Nitrospira,and unclassified bacteria.In addition,the sequences of 11 DGGE bands were closely related to uncultured bacteria.Thus,the bacterial community structure in black soil was stable,and the predominating bacterial groups were uncultured.

  20. Agroforestry practice in villages surrounding Nyamure former ...

    African Journals Online (AJOL)

    cntaganda

    Key words: Agroforestry, fuel wood, tree products, woodlot, forest plantation. INTRODUCTION ... The study area included three administrative cells in the surroundings of Nyamure ..... Table 6: Distance and time spent on firewood collection.

  1. Explaining preferences for home surroundings and locations

    Directory of Open Access Journals (Sweden)

    Hans Skifter Andersen

    2011-01-01

    Full Text Available This article is based on a survey carried out in Denmark that asked a random sample of the population about their preferences for home surroundings and locations. It shows that the characteristics of social surroundings are very important and can be divided into three independent dimensions: avoiding social nuisances, preferring social homogeneity and living close to one’s social network and place of origin. The study shows that most people have many detailed preferences, whereas some have very few. This confirms an earlier theory that some people are very connected to certain places with given characteristics and thus do not have priorities regarding home surroundings and locations. For others, mostly young people and singles, home is just a place to sleep and relax, whereas life is lived elsewhere. For this group, there are only preferences for location and there are few specific preferences for surroundings.

  2. Impacts of grass removal on wetting and actual water repellency in a sandy soil

    Directory of Open Access Journals (Sweden)

    Oostindie Klaas

    2017-03-01

    Full Text Available Soil water content and actual water repellency were assessed for soil profiles at two sites in a bare and grasscovered plot of a sand pasture, to investigate the impact of the grass removal on both properties. The soil of the plots was sampled six times in vertical transects to a depth of 33 cm between 23 May and 7 October 2002. On each sampling date the soil water contents were measured and the persistence of actual water repellency was determined of field-moist samples. Considerably higher soil water contents were found in the bare versus the grass-covered plots. These alterations are caused by differences between evaporation and transpiration rates across the plots. Noteworthy are the often excessive differences in soil water content at depths of 10 to 30 cm between the bare and grass-covered plots. These differences are a consequence of water uptake by the roots in the grass-covered plots. The water storage in the upper 19 cm of the bare soil was at least two times greater than in the grass-covered soil during dry periods. A major part of the soil profile in the grass-covered plots exhibited extreme water repellency to a depth of 19 cm on all sampling dates, while the soil profile of the bare plots was completely wettable on eight of the twelve sampling dates. Significant differences in persistence of actual water repellency were found between the grass-covered and bare plots.

  3. Effect of Different Vegetation Systems on Soil Erosion and Soil Nutrients in Red Soil Region of Southeastern China

    Institute of Scientific and Technical Information of China (English)

    TIAN GUANGMING; WANG FEIER; CHEN YINGXU; HE YUNFENG; FU QINGLIN; S.KUMAR; LIN QI

    2003-01-01

    The effect of different vegetation systems including bamboo plantation (BP), forest ecosystem (CF),citrus orchard (Ctr) and farmland (FL) on erosion and nutrients of red soil were investigated in hilly region of southeastern China to find effective control measures for soil erosion. The results showed that all the vegetation systems could significantly reduce soil erosion and nutrient losses compared to bare land (Br).The ability of different vegetation systems to conserve soil and water was in the order of Ctr > BP > CF > FL > Br. Vegetation could also improve soil fertility. The soil organic matter, total N and total P contents were much higher in all the vegetation systems than in bare land, especially for the top soils. Vegetation systems improved soil physical properties remarkably. Compared to the bare land, soil organic matter, TP,TK and available K, especially soil microbial biomass C, N and P, increased under all the vegetation covers.However, they were still much lower than expected, thus these biological measurements are still needed to be carried out continuously.

  4. Surround-Masking Affects Visual Estimation Ability

    Science.gov (United States)

    Jastrzebski, Nicola R.; Hugrass, Laila E.; Crewther, Sheila G.; Crewther, David P.

    2017-01-01

    Visual estimation of numerosity involves the discrimination of magnitude between two distributions or perceptual sets that vary in number of elements. How performance on such estimation depends on peripheral sensory stimulation is unclear, even in typically developing adults. Here, we varied the central and surround contrast of stimuli that comprised a visual estimation task in order to determine whether mechanisms involved with the removal of unessential visual input functionally contributes toward number acuity. The visual estimation judgments of typically developed adults were significantly impaired for high but not low contrast surround stimulus conditions. The center and surround contrasts of the stimuli also differentially affected the accuracy of numerosity estimation depending on whether fewer or more dots were presented. Remarkably, observers demonstrated the highest mean percentage accuracy across stimulus conditions in the discrimination of more elements when the surround contrast was low and the background luminance of the central region containing the elements was dark (black center). Conversely, accuracy was severely impaired during the discrimination of fewer elements when the surround contrast was high and the background luminance of the central region was mid level (gray center). These findings suggest that estimation ability is functionally related to the quality of low-order filtration of unessential visual information. These surround masking results may help understanding of the poor visual estimation ability commonly observed in developmental dyscalculia.

  5. EAARL Coastal Topography - Northern Gulf of Mexico, 2007: Bare Earth

    Science.gov (United States)

    Smith, Kathryn E.L.; Nayegandhi, Amar; Wright, C. Wayne; Bonisteel, Jamie M.; Brock, John C.

    2009-01-01

    These remotely sensed, geographically referenced elevation measurements of Lidar-derived bare earth (BE) topography were produced as a collaborative effort between the U.S. Geological Survey (USGS), Florida Integrated Science Center (FISC), St. Petersburg, FL; the National Park Service (NPS), Gulf Coast Network, Lafayette, LA; and the National Aeronautics and Space Administration (NASA), Wallops Flight Facility, VA. The purpose of this project is to provide highly detailed and accurate datasets of select barrier islands and peninsular regions of Louisiana, Mississippi, Alabama, and Florida, acquired on June 27-30, 2007. The datasets are made available for use as a management tool to research scientists and natural resource managers. An innovative airborne Lidar instrument originally developed at the NASA Wallops Flight Facility, and known as the Experimental Advanced Airborne Research Lidar (EAARL), was used during data acquisition. The EAARL system is a raster-scanning, waveform-resolving, green-wavelength (532-nanometer) Lidar designed to map near-shore bathymetry, topography, and vegetation structure simultaneously. The EAARL sensor suite includes the raster-scanning, water-penetrating full-waveform adaptive Lidar, a down-looking red-green-blue (RGB) digital camera, a high-resolution multi-spectral color infrared (CIR) camera, two precision dual-frequency kinematic carrier-phase GPS receivers, and an integrated miniature digital inertial measurement unit which provide for submeter georeferencing of each laser sample. The nominal EAARL platform is a twin-engine Cessna 310 aircraft, but the instrument may be deployed on a range of light aircraft. A single pilot, a Lidar operator, and a data analyst constitute the crew for most survey operations. This sensor has the potential to make significant contributions in measuring sub-aerial and submarine coastal topography within cross-environmental surveys. Elevation measurements were collected over the survey area using

  6. EAARL Coastal Topography - Northeast Barrier Islands 2007: Bare Earth

    Science.gov (United States)

    Nayegandhi, Amar; Brock, John C.; Sallenger, A.H.; Wright, C. Wayne; Yates, Xan; Bonisteel, Jamie M.

    2008-01-01

    These remotely sensed, geographically referenced elevation measurements of Lidar-derived bare earth (BE) topography were produced collaboratively by the U.S. Geological Survey (USGS), Florida Integrated Science Center (FISC), St. Petersburg, FL, and the National Aeronautics and Space Administration (NASA), Wallops Flight Facility, VA. This project provides highly detailed and accurate datasets of the northeast coastal barrier islands in New York and New Jersey, acquired April 29-30 and May 15-16, 2007. The datasets are made available for use as a management tool to research scientists and natural resource managers. An innovative airborne Lidar instrument originally developed at the NASA Wallops Flight Facility, and known as the Experimental Advanced Airborne Research Lidar (EAARL), was used during data acquisition. The EAARL system is a raster-scanning, waveform-resolving, green-wavelength (532-nanometer) Lidar designed to map near-shore bathymetry, topography, and vegetation structure simultaneously. The EAARL sensor suite includes the raster-scanning, water-penetrating full-waveform adaptive Lidar, a down-looking red-green-blue (RGB) digital camera, a high-resolution multi-spectral color infrared (CIR) camera, two precision dual-frequency kinematic carrier-phase GPS receivers and an integrated miniature digital inertial measurement unit, which provide for submeter georeferencing of each laser sample. The nominal EAARL platform is a twin-engine Cessna 310 aircraft, but the instrument may be deployed on a range of light aircraft. A single pilot, a Lidar operator, and a data analyst constitute the crew for most survey operations. This sensor has the potential to make significant contributions in measuring sub-aerial and submarine coastal topography within cross-environmental surveys. Elevation measurements were collected over the survey area using the EAARL system, and the resulting data were then processed using the Airborne Lidar Processing System (ALPS), a custom

  7. EAARL Topography - Vicksburg National Military Park 2008: Bare Earth

    Science.gov (United States)

    Nayegandhi, Amar; Brock, John C.; Wright, C. Wayne; Segura, Martha; Yates, Xan

    2008-01-01

    These remotely sensed, geographically referenced elevation measurements of Lidar-derived bare earth (BE) topography were produced as a collaborative effort between the U.S. Geological Survey (USGS), Florida Integrated Science Center (FISC), St. Petersburg, FL; the National Park Service (NPS), Gulf Coast Network, Lafayette, LA; and the National Aeronautics and Space Administration (NASA), Wallops Flight Facility, VA. This project provides highly detailed and accurate datasets of the Vicksburg National Military Park in Mississippi, acquired on March 6, 2008. The datasets are made available for use as a management tool to research scientists and natural resource managers. An innovative airborne Lidar instrument originally developed at the NASA Wallops Flight Facility, and known as the Experimental Advanced Airborne Research Lidar (EAARL), was used during data acquisition. The EAARL system is a raster-scanning, waveform-resolving, green-wavelength (532-nanometer) Lidar designed to map near-shore bathymetry, topography, and vegetation structure simultaneously. The EAARL sensor suite includes the raster-scanning, water-penetrating full-waveform adaptive Lidar, a down-looking red-green-blue (RGB) digital camera, a high-resolution multi-spectral color infrared (CIR) camera, two precision dual-frequency kinematic carrier-phase GPS receivers, and an integrated miniature digital inertial measurement unit, which provide for submeter georeferencing of each laser sample. The nominal EAARL platform is a twin-engine Cessna 310 aircraft, but the instrument may be deployed on a range of light aircraft. A single pilot, a Lidar operator, and a data analyst constitute the crew for most survey operations. This sensor has the potential to make significant contributions in measuring sub-aerial and submarine coastal topography within cross-environmental surveys. Elevation measurements were collected over the survey area using the EAARL system, and the resulting data were then processed

  8. EAARL Coastal Topography-Chandeleur Islands, Louisiana, 2010: Bare Earth

    Science.gov (United States)

    Nayegandhi, Amar; Bonisteel-Cormier, Jamie M.; Brock, John C.; Sallenger, A.H.; Wright, C. Wayne; Nagle, David B.; Vivekanandan, Saisudha; Yates, Xan; Klipp, Emily S.

    2010-01-01

    These remotely sensed, geographically referenced elevation measurements of lidar-derived bare-earth (BE) and submerged topography datasets were produced collaboratively by the U.S. Geological Survey (USGS), St. Petersburg Coastal and Marine Science Center, St. Petersburg, FL, and the National Aeronautics and Space Administration (NASA), Wallops Flight Facility, VA. This project provides highly detailed and accurate datasets of a portion of the Chandeleur Islands, acquired March 3, 2010. The datasets are made available for use as a management tool to research scientists and natural-resource managers. An innovative airborne lidar instrument originally developed at the NASA Wallops Flight Facility, and known as the Experimental Advanced Airborne Research Lidar (EAARL), was used during data acquisition. The EAARL system is a raster-scanning, waveform-resolving, green-wavelength (532-nanometer) lidar designed to map near-shore bathymetry, topography, and vegetation structure simultaneously. The EAARL sensor suite includes the raster-scanning, water-penetrating full-waveform adaptive lidar, a down-looking red-green-blue (RGB) digital camera, a high-resolution multispectral color-infrared (CIR) camera, two precision dual-frequency kinematic carrier-phase GPS receivers, and an integrated miniature digital inertial measurement unit, which provide for sub-meter georeferencing of each laser sample. The nominal EAARL platform is a twin-engine Cessna 310 aircraft, but the instrument may be deployed on a range of light aircraft. A single pilot, a lidar operator, and a data analyst constitute the crew for most survey operations. This sensor has the potential to make significant contributions in measuring sub-aerial and submarine coastal topography within cross-environmental surveys. Elevation measurements were collected over the survey area using the EAARL system, and the resulting data were then processed using the Airborne Lidar Processing System (ALPS), a custom

  9. EAARL Coastal Topography-Pearl River Delta 2008: Bare Earth

    Science.gov (United States)

    Nayegandhi, Amar; Brock, John C.; Wright, C. Wayne; Miner, Michael D.; Yates, Xan; Bonisteel, Jamie M.

    2009-01-01

    These remotely sensed, geographically referenced elevation measurements of Lidar-derived bare earth (BE) topography were produced as a collaborative effort between the U.S. Geological Survey (USGS), Florida Integrated Science Center (FISC), St. Petersburg, FL; the University of New Orleans (UNO), Pontchartrain Institute for Environmental Sciences (PIES), New Orleans, LA; and the National Aeronautics and Space Administration (NASA), Wallops Flight Facility, VA. This project provides highly detailed and accurate datasets of a portion of the Pearl River Delta in Louisiana and Mississippi, acquired March 9-11, 2008. The datasets are made available for use as a management tool to research scientists and natural resource managers. An innovative airborne Lidar instrument originally developed at the NASA Wallops Flight Facility, and known as the Experimental Advanced Airborne Research Lidar (EAARL), was used during data acquisition. The EAARL system is a raster-scanning, waveform-resolving, green-wavelength (532-nanometer) Lidar designed to map near-shore bathymetry, topography, and vegetation structure simultaneously. The EAARL sensor suite includes the raster-scanning, water-penetrating full-waveform adaptive Lidar, a down-looking red-green-blue (RGB) digital camera, a high-resolution multi-spectral color infrared (CIR) camera, two precision dual-frequency kinematic carrier-phase GPS receivers, and an integrated miniature digital inertial measurement unit, which provide for submeter georeferencing of each laser sample. The nominal EAARL platform is a twin-engine Cessna 310 aircraft, but the instrument may be deployed on a range of light aircraft. A single pilot, a Lidar operator, and a data analyst constitute the crew for most survey operations. This sensor has the potential to make significant contributions in measuring sub-aerial and submarine coastal topography within cross-environmental surveys. Elevation measurements were collected over the survey area using the

  10. Effect of sheet and rill erosion on overland flow connectivity in bare agricultural plots

    Science.gov (United States)

    Penuela Fernandez, Andres; Rocio Rodriguez Pleguezuelo, Carmen; Javaux, Mathieu; Bielders, Charles L.

    2014-05-01

    Rill erosion processes generate preferential flow paths that may increase the degree of connectivity of the soil surface and hence strongly modify its hydrological response. However, few studies have tried to quantify the effect of rill development on overland flow connectivity. For this purpose, changes in surface microtopography were monitored on three bare agricultural plots (3 m wide x 10 m long and 11% of slope) in Louvain-la-Neuve (Belgium) under natural rainfall conditions. Digital elevation models of these plots were obtained on a monthly basis over a 1-year period by photogrammetry using the Micmac software. Runoff was collected at the plot outlets. To characterize the hydrological connectivity, a functional connectivity indicator was used, called the relative surface connection function (RSCf). This indicator, which relates the area connected to the outflow boundary to the degree of filling of maximum depression storage (MDS), is fast to compute and was previously shown to be able to capture runoff-relevant connectivity properties. The RSC function was calculated for each DEM and the evolution of overland flow connectivity was quantified and compared to the measured runoff. The results of this study showed that the changes in microtopography resulting from sheet and rill erosion have a strong impact on the hydrological connectivity as reflected in the RSCf. A higher volume of runoff was generated as a consequence of surface sealing and the decrease of the MDS. More rapid runoff initiation was observed as the RSCf evolved from a concave to a convex shape.

  11. Improvement in the biochemical and chemical properties of badland soils by thorny bamboo

    Science.gov (United States)

    Shiau, Yo-Jin; Wang, Hsueh-Ching; Chen, Tsai-Huei; Jien, Shih-Hau; Tian, Guanglong; Chiu, Chih-Yu

    2017-01-01

    Badland soils—which have high silt and clay contents, bulk density, and soil electric conductivity— cover a large area of Southern Taiwan. This study evaluated the amelioration of these poor soils by thorny bamboo, one of the few plant species that grows in badland soils. Soil physiochemical and biological parameters were measured from three thorny bamboo plantations and nearby bare lands. Results show that bamboo increased microbial C and N, soil acid-hydrolysable C, recalcitrant C, and soluble organic C of badland soils. High microbial biomass C to total organic C ratio indicates that soil organic matter was used more efficiently by microbes colonizing bamboo plantations than in bare land soils. High microbial respiration to biomass C ratio in bare land soils confirmed environmentally induced stress. Soil microbes in bare land soils also faced soil organic matter with the high ratio of recalcitrant C to total organic C. The high soil acid-hydrolysable C to total organic C ratio at bamboo plantations supported the hypothesis that decomposition of bamboo litter increased soil C in labile fractions. Overall, thorny bamboo improved soil quality, thus, this study demonstrates that planting thorny bamboo is a successful practice for the amelioration of badland soils.

  12. Improvement in the biochemical and chemical properties of badland soils by thorny bamboo

    Science.gov (United States)

    Shiau, Yo-Jin; Wang, Hsueh-Ching; Chen, Tsai-Huei; Jien, Shih-Hau; Tian, Guanglong; Chiu, Chih-Yu

    2017-01-01

    Badland soils—which have high silt and clay contents, bulk density, and soil electric conductivity— cover a large area of Southern Taiwan. This study evaluated the amelioration of these poor soils by thorny bamboo, one of the few plant species that grows in badland soils. Soil physiochemical and biological parameters were measured from three thorny bamboo plantations and nearby bare lands. Results show that bamboo increased microbial C and N, soil acid-hydrolysable C, recalcitrant C, and soluble organic C of badland soils. High microbial biomass C to total organic C ratio indicates that soil organic matter was used more efficiently by microbes colonizing bamboo plantations than in bare land soils. High microbial respiration to biomass C ratio in bare land soils confirmed environmentally induced stress. Soil microbes in bare land soils also faced soil organic matter with the high ratio of recalcitrant C to total organic C. The high soil acid-hydrolysable C to total organic C ratio at bamboo plantations supported the hypothesis that decomposition of bamboo litter increased soil C in labile fractions. Overall, thorny bamboo improved soil quality, thus, this study demonstrates that planting thorny bamboo is a successful practice for the amelioration of badland soils. PMID:28102291

  13. A Density Functional Study of Bare and Hydrogenated Platinum Clusters

    CERN Document Server

    Sebetci, A

    2006-01-01

    We perform density functional theory calculations using Gaussian atomic-orbital methods within the generalized gradient approximation for the exchange and correlation to study the interactions in the bare and hydrogenated platinum clusters. The minimum-energy structures, binding energies, relative stabilities, vibrational frequencies and the highest occupied and lowest unoccupied molecular-orbital gaps of Pt_nH_m (n=1-5, m=0-2) clusters are calculated and compared with previously studied pure platinum and hydrogenated platinum clusters. We investigate any magic behavior in hydrogenated platinum clusters and find that Pt_4H_2 is more stable than its neighboring sizes. Our results do not agree with a previous conclusion that 3D geometries of Pt tetramer and pentamer are unfavored. On the contrary, the lowest energy structure of Pt_4 is found to be a distorted tetrahedron and that of Pt_5 is found to be a bridge site capped tetrahedron which is a new global minimum for Pt_5 cluster. The successive addition of H ...

  14. AMQ Protocol Based Performance Analysis of Bare Metal Hypervisors

    Directory of Open Access Journals (Sweden)

    Dr Deepak Arora

    2014-06-01

    Full Text Available Cloud computing is one of the most exciting technology because of its cost-reducing approach, flexibility, and scalability. Hypervisor is the essential part of cloud technology; it is a component of software that provides a virtualized hardware environment to support running multiple operating systems concurrently using one physical server. In this paper we took KVM, XEN, Hyper-V and ESXi as hypervisors. We have compared the performance of Virtual Machines (VMs by RabbitMQ message broker server that uses Advanced Message Queuing Protocol(AMQP for breaking messages. We establish the setup on bare metal hypervisor that is installed directly on the hardware of the system. We took SAN (Shared Storage Network server for maintaining the storage of all VMs. By the evaluation of these hyperviosrs we got a brief idea about their performance on different parameters. These results will be beneficial to small enterprise, social group or any private IT firm which is choosing to build small cloud infrastructure with optimal benefits. Experiment results of checking the performance of VMs for all the hypervisors shows that there is performance variation on different applications and workloads of the hypervisors. None of the hypervisors outperform another at every aspect of our comparison.

  15. Late thrombosis of coronary bare-metal stent: Case report

    Directory of Open Access Journals (Sweden)

    Apostolović Svetlana

    2006-01-01

    Full Text Available Stent thrombosis remains the primary cause of death after percutaneous coronary interventions (PCI. Despite modern concepts of PCI, stent thrombosis occurs in 0.5% -2% of elective procedures and even 6% of patients with the acute coronary syndrome (ACS. Stent thrombosis most often develops within the first 48 hours after the PCI, and rarely after a week of stent implantation. Angiographically documented late (>6 months thrombosis of coronary bare-metal stent (BMS is rare, because the stent endothelialization is considered to be completed after four weeks of the intervention. Our patient is a 41 year old male and he had BMS thrombosis 345 days after the implantation, which was clinically manifested as an acute myocardial infarction in the inferoposterolateral localization. Stent Clinical Centre of Serbia, Belgrade thrombosis occurred despite a long term dual antiplatelet therapy and control of known risk factors. Thrombolytic therapy (Streptokinase in a dose of 1 500 000 IU was not successful in reopening the occluded vessel, so the flow through the coronary artery was achieved by rescue balloon angioplasty, followed by implantation of drug eluting stent in order to prevent restenosis.

  16. Electron capture by bare ions on water molecules

    Science.gov (United States)

    Rivarola, Roberto; Montenegro, Pablo; Monti, Juan; Fojón, Omar

    2016-05-01

    Single electron capture from water molecules by impact of bare ions is theoretically investigated at intermediate and high collision energies. This reaction is of fundamental importance to determine the deposition of energy in biological matter irradiated with ion beams (hadrontherapy), dominating other ionizing processes of the target at low-intermediate impact velocities and giving principal contributions to the energetic region where electronic stopping power maximizes. The dynamics of the interaction between the aggregates is described within the one active-electron continuum distorted wave-eikonal initial state theory. The orbitals of the target in the ground state are represented using the approximate self-consistent complete neglect of differential orbitals (SC-CNDO) model. The contribution of different molecular orbitals on the partial cross sections to selected n-principal quantum number projectile states is discriminated as well as the collaboration of these n-states on total cross sections. The latter ones are dominated by capture to n=1 states at high enough energies decreasing their contribution as n increases.

  17. Fortissimo: A Japanese Space Test Of Bare Wire Anode Tethers

    Science.gov (United States)

    Johnson, Les; Fujii, H. A.; Sanmartin, J. R.

    2008-01-01

    A Japanese led international team is developing a suborbital test of orbital-motion-limited (OML) bare wire anode current collection for application to electrodynamic tether (EDT) propulsion. The tether is a tape with a width of 25 mm, thickness of 0.05 mm, and is 300 m in length. This will be the first space test of OML theory. The mission will launch in the summer of 2009 using an S520 Sounding Rocket. During ascent, and above approx. 100 km in attitude, the tape tether will be deployed at a rate of approx. 8 m/s. Once deployed, the tape tether will serve as an anode, collecting ionospheric electrons. The electrons will be expelled into space by a hollow cathode device, thereby completing the circuit and allowing current to flow. The total amount of current collected will be used to assess the validity of OML theory. This paper will describe the objectives of the proposed mission, the technologies to be employed, and the application of the results to future space missions using EDTs for propulsion or power generation.

  18. Analysis of thermionic bare tether operation regimes in passive mode

    Science.gov (United States)

    Sanmartín, J. R.; Chen, Xin; Sánchez-Arriaga, G.

    2017-01-01

    A thermionic bare tether (TBT) is a long conductor coated with a low work-function material. In drag mode, a tether segment extending from anodic end A to a zero-bias point B, with the standard Orbital-motion-limited current collection, is followed by a complex cathodic segment. In general, as bias becomes more negative in moving from B to cathodic end C, one first finds space-charge-limited (SCL) emission covering up to some intermediate point B*, then full Richardson-Dushman (RD) emission reaching from B* to end C. An approximate analytical study, which combines the current and voltage profile equations with results from asymptotic studies of the Vlasov-Poisson system for emissive probes, is carried out to determine the parameter domain covering two limit regimes, which are effectively controlled by just two dimensionless parameters involving ambient plasma and TBT material properties. In one such limit regime, no point B* is reached and thus no full RD emission develops. In an opposite regime, SCL segment BB* is too short to contribute significantly to the current balance.

  19. Effect of Barely flour on jaundice in full-term neonates

    Directory of Open Access Journals (Sweden)

    azam Mohsenzadeh

    2005-08-01

    Conclusions: Our study indicated that phototherapy in conjuction with barely flour therapy is more effective than phototherapy alone. But, people must be informed that affected neonates have to be underwent medical therapy, and barely flour therapy alone is not a reliable treatment.

  20. Hydrodynamic behavior of a bare rod bundle. [LMFBR

    Energy Technology Data Exchange (ETDEWEB)

    Bartzis, J.G.; Todreas, N.E.

    1977-06-01

    The temperature distribution within the rod bundle of a nuclear reactor is of major importance in nuclear reactor design. However temperature information presupposes knowledge of the hydrodynamic behavior of the coolant which is the most difficult part of the problem due to complexity of the turbulence phenomena. In the present work a 2-equation turbulence model--a strong candidate for analyzing actual three dimensional turbulent flows--has been used to predict fully developed flow of infinite bare rod bundle of various aspect ratios (P/D). The model has been modified to take into account anisotropic effects of eddy viscosity. Secondary flow calculations have been also performed although the model seems to be too rough to predict the secondary flow correctly. Heat transfer calculations have been performed to confirm the importance of anisotropic viscosity in temperature predictions. All numerical calculations for flow and heat have been performed by two computer codes based on the TEACH code. Experimental measurements of the distribution of axial velocity, turbulent axial velocity, turbulent kinetic energy and radial Reynolds stresses were performed in the developing and fully developed regions. A 2-channel Laser Doppler Anemometer working on the Reference mode with forward scattering was used to perform the measurements in a simulated interior subchannel of a triangular rod array with P/D = 1.124. Comparisons between the analytical results and the results of this experiment as well as other experimental data in rod bundle array available in literature are presented. The predictions are in good agreement with the results for the high Reynolds numbers.

  1. Sense and nonsense of bare metal stents below the knee.

    Science.gov (United States)

    Caradu, Caroline; Brizzi, Vincenzo; Auque, Heloise; Midy, Dominique; Ducasse, Eric

    2016-10-01

    Critical limb ischemia (CLI) is increasingly present in daily practice, and diabetes is responsible for a preferential below the knee (BTK) localization of the disease. The objective was to determine if there is still a sense to BTK implantation of bare metal stents (BMSs) in CLI patients in the era of drug eluting strategies. An extensive review of the literature was carried out over the last 15 years on the use of BMSs in BTK revascularization based on a PubMed (Medline), EMBASE and PubMed Central search. The Chromis Deep® (Invatec, Roncadelle, Italy) was the first dedicated stent in BTK lesions, followed by passive coated BMSs developed in an attempt to inhibit platelets deposition. Comparative results showed no advantage of primary BMS implantation over peripheral transluminal angioplasty (PTA) in improving primary patency rates, Rutherford classification or wound healing and the place of BMSs was restricted to bailout spot stenting. The fear of patency loss in connection with possible stent fractures led to an interest towards nitinol stents, but results were disappointing, especially in patients with severely calcified lesions. Drug-eluting stents (DESs) were then developed and showed better long-term primary patency, restenosis and freedom from target lesion revascularization (TLR) rates, even in long calcified lesions against BMS or drug eluting balloons (DEB). However, limb salvage and wound healing rates were not significantly improved. Primary BMS implantation showed no advantage over PTA and as of today DES trials have not shown enough clinical or economic benefit. Thus, BMSs are recommended over DESs, and only as a bailout strategy in case of flow limiting dissection or recoil. Quality trials assessing long-term clinically relevant outcomes, evolution in stents designs and vessel preparation could lead to a change in those recommendations.

  2. A framework for sourcing of evaporation between saturated and unsaturated zone in bare soil condition

    NARCIS (Netherlands)

    Balugani, E.; Lubczynski, M.W.; Metselaar, Klaas

    2016-01-01

    Sourcing subsurface evaporation (Ess) into groundwater (Eg) and unsaturated zone (Eu) components has received little scientific attention so far, despite its importance in water management and agriculture. We propose a novel sourcing framework, with its implementa

  3. Study of the anisotropy of thermal infrared emissivity of inorganic bare soils at different moisture levels

    OpenAIRE

    García Santos, Vicente

    2013-01-01

    I. Introducción La técnica responsable de obtener información de un objeto lejano si contacto físico con éste, se llama Teledetección. Esta técnica ha demostrado ser una alternativa muy ventajosa frente a otros métodos cuya adquisición de datos es más lenta y costosa. La Teledetección usa sensores a bordo de satélites, para medir la radiación emitida por las superficies terrestres en diferentes partes del espectro electromagnético, con la intención de entender mejor los procesos físicos oc...

  4. Soil Strength Criteria for Operation of Fighter Aircraft on Unsurfaced Airfields; Bare Base Support.

    Science.gov (United States)

    performance jet fighter aircraft on unsurfaced airfields. Two specially prepared test sections were constructed with four test items in each section...Test section 1 consisted of two lean clay test items and two heavy clay test items . Test section 2 consisted of four items: clayey sand, lean clay

  5. [The bare area of the proximal ulna : An anatomical study on optimizing olecranon osteotomy].

    Science.gov (United States)

    Hackl, M; Lappen, S; Neiss, W F; Scaal, M; Müller, L P; Wegmann, K

    2016-10-01

    Olecranon osteotomy is an established approach for the treatment of distal humerus fractures. It should be performed through the bare area of the proximal ulna to avoid iatrogenic cartilage lesions. The goal of this study was to analyze the anatomy of the proximal ulna with regard to the bare area and, thereby, to optimize the hitting area of the bare area when performing olecranon osteotomy. The bare areas of 30 embalmed forearm specimens were marked with a radiopaque wire and visualized three-dimensionally with a mobile C‑arm. By means of 3D reconstructions of the data sets, the following measurements were obtained: height of the bare area; span of the bare area-hitting area in transverse osteotomy; ideal angle for olecranon osteotomy to maximize the hitting area of the bare area; distance of the posterior olecranon tip to the entry point of the transverse osteotomy and the ideal osteotomy. The height of the bare area was 4.92 ± 0.81 mm. The hitting area of the transverse osteotomy averaged 3.73 ± 0.89 mm. The "ideal" angle for olecranon osteotomy was 30.7° ± 4.19°. The distance of the posterior olecranon tip to the entry point was 14.08 ± 2.75 mm for the transverse osteotomy and 24.21 ± 3.15 mm for the ideal osteotomy. The hitting area of the bare area in the ideal osteotomy was enhanced significantly when compared to the transverse osteotomy (p osteotomy of the olecranon. Moreover, a 30° angulation of the osteotomy can significantly increase the hitting area of the bare area.

  6. Smart Chips for Smart Surroundings - 4S

    NARCIS (Netherlands)

    Schuler, Eberhard; König, Ralf; Becker, Jürgen; Rauwerda, Gerard; Burgwal, van de Marcel; Smit, Gerard J.M.; Cardoso, João M.P.; Hübner, Michael

    2011-01-01

    The overall mission of the 4S project (Smart Chips for Smart Surroundings) was to define and develop efficient flexible, reconfigurable core building blocks, including the supporting tools, for future Ambient System Devices. Reconfigurability offers the needed flexibility and adaptability, it provid

  7. [Effects of soil crusts on surface hydrology in the semiarid Loess hilly area].

    Science.gov (United States)

    Wei, Wei; Wen, Zhi; Chen, Li-Ding; Chen, Jin; Wu, Dong-Ping

    2012-11-01

    Soil crusts are distributed extensively in the Chinese Loess Plateau and play key roles in surface hydrological processes. In this study, a typical loess hilly region in Anjiagou catchment, Dingxi city, Gansu province was selected as the study region, and soil crusts in the catchment were investigated. Then, the hydrological effect of soil crusts was studied by using multi-sampling and hydrological monitoring experiments. Several key results were shown as follows. Firstly, compared with bared soil without crust cover, soil crusts can greatly reduce the bulk density, improve the porosity of soil, and raise the holding capacity of soil moisture which ranges from 1.4 to 1.9 times of that of bared soil. Secondly, the role of soil crust on rainfall interception was very significant. Moss crust was found to be strongest on rainfall interception, followed by synantectic crusts and lichen crusts. Bared soil without covering crusts was poorest in resisting rainfall splash. Thirdly, hydrological simulation experiments indicate that soil crusts play a certain positive role in promoting the water infiltration capacity, and the mean infiltration rate of the crusted soil was 2 times higher than that of the no-crust covered soils. While the accumulated infiltrated water amounts was also far higher than that of the bared soil.

  8. POLYCHLORINATED BIPHENYLS IN HOUSE DUST AND YARD SOIL NEAR A SUPERFUND SITE. (R825173)

    Science.gov (United States)

    Polychlorinated biphenyls (PCBs) were measured in house dust and yard soil at 34 homes surrounding New Bedford Harbor during dredging of highly contaminated harbor sediments. PCBs can volatilize from sediments and seawater and subsequently deposit on surrounding soil, resulting i...

  9. The roles of nematodes in nitrogen and phosphorous availability, plant uptake and growth in organically amended soils

    Science.gov (United States)

    Gebremikael, Mesfin; Buchan, David; De Neve, Stefaan

    2017-04-01

    Several studies have shown that soil biota contributes significantly to the crucial ecosystem functions and services such as organic matter decomposition and nutrient cycling. The contribution of each group of soil organisms may vary depending primarily on their feeding behavior. The magnitude of the ecosystem services by the biota may also depend on the interactions amongst the soil biota groups and their surrounding environment, for instance, biochemical characteristics of the externally added organic material. However, only a few studies considered these interactions concurrently. Here, we investigated the effects of fauna-microbe-plant interactions on organic matter decomposition and nutrient cycling by applying different organic materials spanning a range of C:N ratios and presumed N availability. Nematodes were selected as model fauna because they are the most abundant soil metazoans that have a diversified feeding strategy and interact very intimately with microbes, other fauna, and plants. A series of incubation experiments were conducted in bare and planted microcosms under controlled conditions using fresh soil collected from an agricultural field and defaunated by gamma irradiation. In the first experiment without plants, the defaunated soil cores were either left unamended (UNA) or received lignin-rich low N compost (COI), N-rich compost (COV), fresh manure (MAN) or chopped clover (CLO). The entire free-living soil nematode community was extracted from unirradiated fresh soil and reinoculated into half of the soil cores that had been defaunated by gamma irradiation. Two treatments: with (+Nem) and without (-Nem) nematodes were compared for soil nitrogen and phosphorus availability, plant uptake, and PLFA signatures over time during a 105-days incubation. The same experimental setup was used to investigate further the CLO amendment in the presence of plants (rye grass was used as a model plant). Nematodes were extracted and assigned to feeding groups

  10. Clinical and angiographic outcomes after intracoronary bare-metal stenting.

    Directory of Open Access Journals (Sweden)

    I-Chang Hsieh

    Full Text Available BACKGROUND: Data from a large patient population regarding very long-term outcomes after BMS implantation are inadequate. This study aimed to evaluate the very long-term (8-17 years clinical and long-term (3-5 years angiographic outcomes after intracoronary bare-metal stenting (BMS. METHODS AND RESULTS: From the Cardiovascular Atherosclerosis and Percutaneous TrAnsluminal INterventions (CAPTAIN registry, a total of 2391 patients with 2966 lesions treated with 3190 BMSs between November 1995 and May 2004 were evaluated. In total, 1898 patients with 2364 lesions, and 699 patients with 861 lesions underwent 6-month and 3- to 5- year angiographic follow-up, respectively. During a mean follow-up period of 149 ± 51 months, 18.6% of the patients died (including 10.8% due to cardiac death, 6.1% developed reinfarction, 16.2% had target lesion revascularization (including 81% of the patients within the first year, 14.5% underwent new lesion stenting (including 72% of the patients after 3 years, 2.4% underwent coronary bypass surgery, and 1.6% had definite stent thrombosis. The overall cardiovascular event-free survival rate was 58.5%. The 6-month angiographic study indicated a 20% restenosis rate. The minimal luminal diameter increased from 0.65 ± 0.44 mm to 3.02 ± 0.46 mm immediately after stenting, decreased to 2.06 ± 0.77 mm at the 6-month follow-up, and increased to 2.27 ± 0.68 mm at the 3- to 5-year follow-up. CONCLUSIONS: This study provides clinical and angiographic results from a large population of patients who underwent BMS implantations after a long-term follow-up period (149 ± 51 months. The progression of coronary atherosclerosis developed over time, and presented with new lesion required stent implantation. The follow-up angiographic findings reconfirmed the late and sustained improvement in luminal diameter between 6 months and 3-5 years.

  11. Nuda vida y goce. // Bare life and jouissance.

    Directory of Open Access Journals (Sweden)

    Laura Arias.

    2010-06-01

    Full Text Available From the point of view that connects politics and psychoanalysis, the aim of this essay is to investigate the causes of the annihilation of the subject in the totalitarian regimes, making him a victim of power, reduced to a bare life. This question leads us to analyze the jouissance within the frame of a regime that proposes the unification of a universal jouissance. These questions are considered to be relevant in the field that makes possible the intersection between politics and subjectivity. The direct proposal of this essay is related to thought, by trying to bring thought into play, in conjunction with the concepts of jouissance and the annihilation of the subject in the totalitarian regimes. It deals with the articulation between thought and jouissance and uses these ideas like conceptual tools, with the aim of considering the subjectivity of the time. // Desde el punto de vista que relaciona la política con el psicoanálisis, la propuesta de este ensayo trata de interrogar qué produce la aniquilación del sujeto en los regímenes totalitarios, al convertirlo en víctimas del poder, reducido a nuda vida. Este cuestionamiento nos conduce a preguntarnos sobre el goce en el marco de un régimen que propone la unificación de un goce universal. Consideramos pertinentes estos cuestionamientos en la vertiente que posibilita el cruce entre política y subjetividad. La propuesta expresa de este ensayo se relaciona con el pensar; con la posibilidad de recuperar una reflexión sobre el pensar, tratando de ponerlo en escena, en conjunción con el goce y la aniquilación del sujeto en los regímenes totalitarios. Se trata de una articulación entre pensar y goce y toma estas nociones como herramientas conceptuales, en el interés por considerar la subjetividad de la época.

  12. The Interstellar Cloud Surrounding the Solar System

    Science.gov (United States)

    Frisch, P. C.

    Ultraviolet spectral data of nearby stars indicate that the cloud surrounding the solar system has an average neutral density n(HI)~0.1 cm-3, temperature ~6800 K, and turbulence ~1.7 km/s. Comparisons between the anomalous cosmic ray data and ultraviolet data suggest that the electron density is in the range n(e-)~0.22 to 0.44 cm-3. This cloud is flowing past the Sun from a position centered in the Norma-Lupis region. The cloud properties are consistent with interstellar gas which originated as material evaporated from the surfaces of embedded clouds in the Scorpius-Centaurus Association, and which was then displaced towards the Sun by a supernova event about 4 Myrs ago. The Sun and surrounding cloud velocities are nearly perpendicular in space, and this cloud is sweeping past the Sun. The morphology of this cloud can be reconstructed by assuming that the cloud moves in a direction parallel to the surface normal. With this assumption, the Sun entered the surrounding cloud 2000 to 8000 years ago, and is now about 0.05 to 0.16 pc from the cloud surface. Prior to its recent entry into the surrounding cloud complex, the Sun was embedded in a region of space with average density lower than 0.0002 cm-3. If a denser cloud velocity component seen towards alpha Cen A,B is real, it will encounter the solar system within 50,000 yr. The nearby magnetic field seen upwind has a spatial orientation that is parallel to the cloud surface. The nearby star Sirius is viewed through the wake of the solar system, but this direction also samples the hypothetical cloud interface. Comparisons of anomalous cosmic ray and interstellar absorption line data suggest that trace elements in the surrounding cloud are in ionization equilibrium. Data towards nearby white dwarfs indicate partial helium ionization, N(N(HI)(/N(HeI)>~13.7, which is consistent with pickup ion data within the solar system if less than 40% hydrogen ionization occurs in the heliopause region. However, the white dwarfs may

  13. Soil Albedo in Relation to Soil Color, Moisture and Roughness

    Science.gov (United States)

    Fontes, Adan Fimbres

    Land surface albedo is the ratio of reflected to incident solar radiation. It is a function of several surface parameters including soil color, moisture, roughness and vegetation cover. A better understanding of albedo and how it changes in relation to variations in these parameters is important in order to help improve our ability to model the effects of land surface modifications on climate. The objectives of this study were (1) To determine empirical relationships between smooth bare soil albedo and soil color, (2) To develop statistical relationships between albedo and ground-based thematic mapper (TM) measurements of spectral reflectances, (3) To determine how increased surface roughness caused by tillage reduces bare soil albedo and (4) To empirically relate albedo with TM data and other physical characteristics of mixed grass/shrubland sites at Walnut Gulch Watershed. Albedos, colors and spectral reflectances were measured by Eppley pyranometer, Chroma Meter CR-200 and a Spectron SE-590, respectively. Measurements were made on two field soils (Gila and Pima) at the Campus Agricultural Center (CAC), Tucson, AZ. Soil surface roughness was measured by a profile meter developed by the USDA/ARS. Additional measurements were made at the Maricopa Agricultural Center (MAC) for statistical model testing. Albedos of the 15 smooth, bare soils (plus silica sand) were determined by linear regression to be highly correlated (r^2 = 0.93, p > 0.01) with color values for both wet and dry soil conditions. Albedos of the same smooth bare soils were also highly correlated (r^2>=q 0.86, p > 0.01) with spectral reflectances. Testing of the linear regression equations relating albedo to soil color and spectral reflectances using the data from MAC showed a high correlation. A general nonlinear relationship given by y = 8.366ln(x) + 37.802 r^2 = 0.71 was determined between percent reduction in albedo (y) and surface roughness index (x) for wet and dry Pima and Gila field soils

  14. Persistent Confusion and Controversy Surrounding Gene Patents

    Science.gov (United States)

    Guerrini, Christi J.; Majumder, Mary A.; McGuire, Amy L.

    2016-01-01

    There is persistent confusion and controversy surrounding basic issues of patent law relevant to the genomics industry. Uncertainty and conflict can lead to the adoption of inefficient practices and exposure to liability. The development of patent-specific educational resources for industry members, as well as the prompt resolution of patentability rules unsettled by recent U.S. Supreme Court decisions, are therefore urgently needed. PMID:26849516

  15. Dynamics of soil organic matter in primary and secondary forest succession on sandy soils in The Netherlands: An application of the ROMUL model

    NARCIS (Netherlands)

    Nadporozhskaya, M.A.; Mohren, G.M.J.; Chertov, O.G.; Komarov, A.S.; Mikhailov, A.V.

    2006-01-01

    We applied the simulation model ROMUL of soil organic matter dynamics in order to analyse and predict forest soil organic matter (SOM) changes following stand growth and also to identify gaps of data and modelling problems. SOM build-up was analysed (a) from bare sand to forest soil during a primary

  16. Dynamics of soil organic matter in primary and secondary forest succession on sandy soils in The Netherlands: An application of the ROMUL model

    NARCIS (Netherlands)

    Nadporozhskaya, M.A.; Mohren, G.M.J.; Chertov, O.G.; Komarov, A.S.; Mikhailov, A.V.

    2006-01-01

    We applied the simulation model ROMUL of soil organic matter dynamics in order to analyse and predict forest soil organic matter (SOM) changes following stand growth and also to identify gaps of data and modelling problems. SOM build-up was analysed (a) from bare sand to forest soil during a primary

  17. Multilayer soil model for improvement of soil moisture estimation using the small perturbation method

    Science.gov (United States)

    Song, Kaijun; Zhou, Xiaobing; Fan, Yong

    2009-12-01

    A multilayer soil model is presented for improved estimation of soil moisture content using the first-order small perturbation method (SPM) applied to measurements of radar backscattering coefficient. The total reflection coefficient of the natural bare soil including volume scattering contribution is obtained using the multilayer model. The surface reflection terms in SPM model are replaced by the total reflection coefficient from the multilayer soil surface in estimating soil moisture. The difference between the modified SPM model and the original SPM surface model is that the modified SPM model includes both the surface scattering and the volumetric scattering of the natural bare soil. Both the modified SPM model and the original SPM model are tested in soil moisture retrievals using experimental microwave backscattering coefficient data in the literature. Results show that the mean square errors between the measured data and the values estimated by the modified SPM model from all samples are 5.2%, while errors from the original SPM model are 8.4%. This indicates that the capability of estimating soil moisture by the SPM model is improved when the surface reflection terms are replaced by the total reflection coefficients of multilayer soil model over bare or very sparsely vegetation covered fields.

  18. Irrigation scheduling, freeze warning and soil salinity detecting. [in Cameron County Texas

    Science.gov (United States)

    Wiegand, C. L. (Principal Investigator)

    1975-01-01

    The author has identified the following significant results. Correlations of multispectral scanner (MSS) digital data differences between vegetated and bare soil areas with salinity levels from the eight saline areas using MSS bands seven and ten in the infrared region were significant. Correlations were derived for Cameron County, Texas. Detection of saline soils may be possible, using either film density readings or multispectral scanner data, when the lower reflectance of vegetation on highly saline soil and the higher reflectance of vegetation on lower saline soil are considered by using film on MSS contrasts between vegetation and bare soil.

  19. Spatial variability of soil salinity in coastal saline soil at different scales in the Yellow River Delta, China.

    Science.gov (United States)

    Wang, Zhuoran; Zhao, Gengxing; Gao, Mingxiu; Chang, Chunyan

    2017-02-01

    The objectives of this study were to explore the spatial variability of soil salinity in coastal saline soil at macro, meso and micro scales in the Yellow River delta, China. Soil electrical conductivities (ECs) were measured at 0-15, 15-30, 30-45 and 45-60 cm soil depths at 49 sampling sites during November 9 to 11, 2013. Soil salinity was converted from soil ECs based on laboratory analyses. Our results indicated that at the macro scale, soil salinity was high with strong variability in each soil layer, and the content increased and the variability weakened with increasing soil depth. From east to west in the region, the farther away from the sea, the lower the soil salinity was. The degrees of soil salinization in three deeper soil layers are 1.14, 1.24 and 1.40 times higher than that in the surface soil. At the meso scale, the sequence of soil salinity in different topographies, soil texture and vegetation decreased, respectively, as follows: depression >flatland >hillock >batture; sandy loam >light loam >medium loam >heavy loam >clay; bare land >suaeda salsa >reed >cogongrass >cotton >paddy >winter wheat. At the micro scale, soil salinity changed with elevation in natural micro-topography and with anthropogenic activities in cultivated land. As the study area narrowed down to different scales, the spatial variability of soil salinity weakened gradually in cultivated land and salt wasteland except the bare land.

  20. Changes in Mercury Volatilization between Planted and Unplanted Soils

    Science.gov (United States)

    Briggs, C.; Gustin, M. S.

    2010-12-01

    An important question with respect to the Hg biogeochemical cycle is how does the presence of plants affect the flux of Hg from a soil? Previous research has shown that with leaf development over a growing season and increased soil shading Hg emission decreases, while others have suggested that increased activity of rhizosphere bacteria due to the presence of plants would result in the increased Hg emission from soils. This study examined Hg release to the air associated with low Hg containing soils from three states—Indiana, Alabama, and Ohio over 24 h periods. Hg flux was quantified on a seasonal time step over one year for bare soil and for soil when planted with perennial rye grass (Lolium perennel). For the latter fluxes were measured 5 and 10 weeks after planting. Preliminary data assessment suggests that both planted and unplanted substrates in the summer are generally a net source of Hg to the atmosphere with total daily flux ranging from -50 to 1000 ng/m2 day. Fluxes observed for planted soils exhibited diel trends that were the opposite of that measured for bare soils, that is maximum Hg flux was observed during the night instead of at midday. Planted Indiana and Ohio soils emitted a lower Hg flux than the bare soils while the Alabama soils were not consistent. Good correlations were observed between flux versus soil moisture, soil temperature, local ozone concentration, and solar radiation for bare soils however correlation coefficients were not as strong for the planted materials. Mercury concentration of foliar material showed that plant uptake could not account for reduced flux at midday. This work suggests that the presence of plants does alter the flux of Hg occurring from soils.

  1. Identification of -SiC surrounded by relatable surrounding diamond medium using weak Raman surface phonons

    Indian Academy of Sciences (India)

    Mohan Kumar Kuntumalla; Harish Ojha; Vadali Venkata Satya Siva Srikanth

    2013-11-01

    It is difficult to detect -SiC using micro-Raman scattering, if it is surrounded by carbon medium. Here, -SiC is identified in the presence of a relatable surrounding diamond medium using subtle, but discernible Raman surface phonons. In this study, diamond/-SiC nanocomposite thin film system is considered in which nanosized -SiC crystallites are surrounded by a relatable nanodiamond medium that leads to the appearance of a weak Raman surface phonon band at about 855 cm-1. Change in the nature of the surrounding material structure and its volume content when relatable, will affect the resultant Raman response of -SiC phase as seen in the present case of diamond/-SiC nanocomposite thin films.

  2. Homogenization of the soil surface following fire in semiarid grasslands

    Science.gov (United States)

    Carleton S. White

    2011-01-01

    Semiarid grasslands accumulate soil beneath plant "islands" that are raised above bare interspaces. This fine-scale variation in microtopographic relief is plant-induced and is increased with shrub establishment. Research found that fire-induced water repellency enhanced local-scale soil erosion that reduced variation in microtopographic relief, suggesting...

  3. 30 CFR 77.1802 - Insulation of trolley wires, trolley feeder wires and bare signal wires; guarding of trolley...

    Science.gov (United States)

    2010-07-01

    ... wires and bare signal wires; guarding of trolley wires and trolley feeder wires. 77.1802 Section 77.1802... Wires and Trolley Feeder Wires § 77.1802 Insulation of trolley wires, trolley feeder wires and bare..., and bare signal wires shall be adequately guarded: (a) At all points where men are required to work or...

  4. 30 CFR 75.1003 - Insulation of trolley wires, trolley feeder wires and bare signal wires; guarding of trolley...

    Science.gov (United States)

    2010-07-01

    ... wires and bare signal wires; guarding of trolley wires and trolley feeder wires. 75.1003 Section 75.1003... Insulation of trolley wires, trolley feeder wires and bare signal wires; guarding of trolley wires and trolley feeder wires. Trolley wires, trolley feeder wires, and bare signal wires shall be insulated...

  5. 2010 USGS/NASA Experimental Advanced Airborne Research Lidar (EAARL): Chandeleur Islands, Louisiana (Bare-Earth)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A bare-earth digital elevation map (also known as a Digital Elevation Model, or DEM) of a portion of the Chandeleur Islands, Louisiana, was produced from remotely...

  6. LiDAR Derived Bare Earth Digital Elevation Model: Camas National Wildlife Refuge

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This dataset represents the Camas National Wildlife Refuge survey area in Jefferson and Clark County, ID. This bare earth digital elevation model (DEM) represent...

  7. LiDAR Derived Bare Earth Digital Elevation Model: Camas National Wildlife Refuge

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This dataset represents the Camas National Wildlife Refuge survey area in Jefferson and Clark County, ID. This bare earth digital elevation model (DEM) represent the...

  8. EAARL Coastal Topography--Assateague Island National Seashore, 2008: Bare Earth

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — A bare-earth elevation map (also known as a Digital Elevation Model, or DEM) of the Assateague Island National Seashore in Virginia and Maryland was produced from...

  9. EAARL Coastal Topography--Eastern Florida, Post-Hurricane Frances, 2004: Bare Earth

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — A bare-earth digital elevation map (also known as a Digital Elevation Model, or DEM) of a portion of the eastern Florida coastline was produced from remotely sensed,...

  10. EAARL Coastal Topography--Western Florida, Post-Hurricane Charley, 2004: Seamless (Bare Earth and Submerged)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — A seamless (bare-earth and submerged) elevation map (also known as a Digital Elevation Model, or DEM) of a portion of western Florida, post-Hurricane Charley, was...

  11. EAARL Coastal Topography--Assateague Island National Seashore, 2008: Bare Earth

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — A bare-earth elevation map (also known as a Digital Elevation Model, or DEM) of the Assateague Island National Seashore in Virginia and Maryland was produced from...

  12. EAARL Coastal Topography--Assateague Island National Seashore, Maryland and Virginia, 2005: Bare Earth

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — A bare-earth topography Digital Elevation Model (DEM) mosaic for the Assateague Island National Seashore was produced from remotely sensed, geographically referenced...

  13. Galvanic effects on electrochemical behaviors of bare surface of 304 stainless steel

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    The bare surface of 304 stainless steel is produced by the fast fracture method. The influence of the surfacegalvanic cell on the electrochemical behaviors of bare surface of 304 stainless steel has been investigated in H2SO4 solutionswith different concentrations. The results show that the solution corrosivity level and the area ratio influence the surfacegalvanic effects caused by the inhomogeneity between the free-film surface of alloy and the passive surface. The surfacegalvanic effects can speed up the dissolution rate of the bare surface of the alloy and will change the electrochemical behav-ior of bare surface. With the increase of the area ratio between passive surface and fractured surface, the galvanic potentialbecomes more positive and, in the range of passive potential, both galvanic current and the peak fracture current increase

  14. EAARL Coastal Topography--Western Florida, Post-Hurricane Charley, 2004: Seamless (Bare Earth and Submerged)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — A seamless (bare-earth and submerged) elevation map (also known as a Digital Elevation Model, or DEM) of a portion of western Florida, post-Hurricane Charley, was...

  15. Assessing the adequacy of the bare optical potential in near-barrier fusion calculation

    Energy Technology Data Exchange (ETDEWEB)

    Canto, L.F. [Universidade Federal do Rio de Janeiro, Instituto de Fisica, CP 68528, Rio de Janeiro (Brazil); Gomes, P.R.S.; Lubian, J. [Universidade Federal Fluminense, Instituto de Fisica, Niteroi, R.J. (Brazil); Hussein, M.S. [Universidade de Sao Paulo, Instituto de Estudos Avancados, C. P. 72012, Sao Paulo-SP (Brazil); Universidade de Sao Paulo, Instituto de Fisica, C. P. 66318, Sao Paulo (Brazil); Lotti, P. [INFN, Padova (Italy)

    2014-05-15

    We critically examine the differences among the different bare nuclear interactions used in near-barrier heavy-ion fusion analysis and coupled-channels calculations, and discuss the possibility of extracting the barrier parameters of the bare potential from above-barrier data. We show that the choice of the bare potential may be critical for the analysis of the fusion cross sections. Although this may seem trivial, several recent papers use different bare potentials and reach different conclusions, especially when weakly bound systems are considered and possible relatively small fusion cross section enhancements or suppressions are found. We show also that the barrier parameters taken from above-barrier data may be very wrong. (orig.)

  16. EAARL Coastal Topography--Eastern Florida, Post-Hurricane Frances, 2004: Bare Earth

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — A bare-earth digital elevation map (also known as a Digital Elevation Model, or DEM) of a portion of the eastern Florida coastline was produced from remotely sensed,...

  17. EAARL Coastal Topography--Northern Assateague Island National Seashore, Maryland and Virginia, 2003: Bare Earth

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — A bare-earth topography Digital Elevation Model (DEM) mosaic for the northern half of Assateague Island National Seashore was produced from remotely sensed,...

  18. Biolimus-eluting stents with biodegradable polymer versus bare-metal stents in acute myocardial infarction

    DEFF Research Database (Denmark)

    Räber, Lorenz; Kelbæk, Henning; Taniwaki, Masanori

    2014-01-01

    BACKGROUND: This study sought to determine whether the 1-year differences in major adverse cardiac event between a stent eluting biolimus from a biodegradable polymer and bare-metal stents (BMSs) in the COMFORTABLE trial (Comparison of Biolimus Eluted From an Erodible Stent Coating With Bare Meta...... to improve cardiovascular events compared with BMS beyond 1 year. CLINICAL TRIAL REGISTRATION URL: http://www.clinicaltrials.gov. Unique identifier: NTC00962416....

  19. Explaining preferences for home surroundings and locations

    DEFF Research Database (Denmark)

    Andersen, Hans Skifter

    2011-01-01

    : avoiding social nuisances, preferring social homogeneity and living close to one’s social network and place of origin. The study shows that most people have many detailed preferences, whereas some have very few. This confirms an earlier theory that some people are very connected to certain places...... with given characteristics and thus do not have priorities regarding home surroundings and locations. For others, mostly young people and singles, home is just a place to sleep and relax, whereas life is lived elsewhere. For this group, there are only preferences for location and there are few specific...

  20. Effects of temperature, moisture and soil type on seedling emergence and mortality of riparian plant species

    NARCIS (Netherlands)

    Heerdt, ter Gerard N.J.; Veen, Ciska G.F.; Putten, van der Wim H.; Bakker, Jan P.

    2017-01-01

    Restoration of riparian plant communities on bare soil requires germination of seeds and establishment of seedlings. However, species that are present in the soil seed bank do not always establish in the vegetation. Temperature, moisture conditions and soil type could play a major role in the

  1. Effects of temperature, moisture and soil type on seedling emergence and mortality of riparian plant species

    NARCIS (Netherlands)

    Ter Heerdt, Gerard N.J.; Veen, Ciska G.F.; Van der Putten, Wim H.; Bakker, Jan P.

    Abstract Restoration of riparian plant communities on bare soil requires germination of seeds and establishment of seedlings. However, species that are present in the soil seed bank do not always establish in the vegetation. Temperature, moisture conditions and soil type could play a major role in

  2. Effects of temperature, moisture and soil type on seedling emergence and mortality of riparian plant species

    NARCIS (Netherlands)

    ter Heerdt, Gerard N. J.; Veen, Ciska G.F.; van der Putten, Wim H.; Bakker, Jan P.

    Restoration of riparian plant communities on bare soil requires germination of seeds and establishment of seedlings. However, species that are present in the soil seed bank do not always establish in the vegetation. Temperature, moisture conditions and soil type could play a major role in the

  3. Comparison of buried soil sensors, surface chambers and above ground measurements of carbon dioxide fluxes

    Science.gov (United States)

    Soil carbon dioxide (CO2) flux is an important component of the terrestrial carbon cycle. Accurate measurements of soil CO2 flux aids determinations of carbon budgets. In this study, we investigated soil CO2 fluxes with time and depth and above ground CO2 fluxes in a bare field. CO2 concentrations w...

  4. Physical characterization, spectral response and remotely sensed mapping of Mediterranean soil surface crusts

    NARCIS (Netherlands)

    Jong, S.M. de; Addink, E.A.; Duijsing, D.; Beek, L.P.H. van

    2011-01-01

    Soil surface crusting and sealing are frequent but unfavorable processes in Mediterranean areas. Soil crust and seals form on bare soil subject to high-intensity rainfall, resulting in a hard, impenetrable layer that impedes infiltration and hampers the germination and establishment of plants. The a

  5. Residue cover effects on soil erosion and the infiltration in black soil under simulated rainfall experiments

    Science.gov (United States)

    Xin, Yan; Xie, Yun; Liu, Yuxin; Liu, Hongyuan; Ren, Xiaoyu

    2016-12-01

    Residue cover is widely used in the Northeastern China Black Soil Region for soil erosion control due to the large annual production of crop residues. Quantitative evaluations of the residue cover effects on preventing soil loss and on the cumulative infiltration amount are thus desirable. Herein, rainfall simulation experiments were conducted using simulators and soil flumes to study the effects of residue cover on soil erosion and infiltration under various rainfall events. Laboratory experiments were designed utilizing five levels of residue cover (bare, 15%, 35%, 55% and 75%), four rainfall intensities (30 mm/h, 60 mm/h, 90 mm/h and 120 mm/h), two soil moistures (dry and wet run) and a fixed slope of 7%. The results indicated that residue cover strongly affects runoff, soil loss and infiltration. Equations for predicting the soil loss ratio and infiltration ratio (the ratio of residue cover soil to bare soil) are herein proposed based on nonlinear curve regression. An empirical approach presented as the infiltration ratios multiplied Philip's equation derived from bare soil was established for estimating the cumulative infiltration amounts under various residue covers. The equation was demonstrated to be suitable for infiltration prediction for black soil by the root mean square error value and 1:1 line method. In addition, the relationship between the residue cover and biomass of corn residues was provided in order to enable accurate measurement of the residue coverage. These derived equations could be used for soil erosion and infiltration prediction under no-till and residue cover management conditions in the black soil region.

  6. Extraction of two kinds of bare lands around cities and its significance to city development

    Science.gov (United States)

    Li, R.; Yue, Y. M.; Liu, Bo; Zhang, X.; Tian, X.

    2014-05-01

    In china, especially in the North and Northwest, many cities suffer sand-dust or sand-storm attacks in winter and spring. There are two sand sources forming the bad weather, local sand source and other source out of local area. The second kind source needs state level activities to control sand movement and recover local ecological environment. For the local government, it should pay much attention to decreasing its inner sand & dust source, because the sand-stormy or sand-dusty weather causing by the local sand source usually comes abruptly and brings much damage frequently, and it is also hard to forecast it. However, people always emphasize all-year bare land controlling and pay less attention to seasonal bare land (especially in winter and spring seasons) which caused by unreasonable agricultural pattern. In this paper, taking Beijing as the test area, using MODIS vegetation index time-series data, all-year and seasonal bare land had been classified. The data set used was 16-day composited EVI time-series with a 250m spatial resolution. After filtered and reconstructed, this paper applied the parallelepiped classification algorithm to the data set, and emphasized the all-year bare land with lower EVI value and seasonal bare land with lower EVI value just in spring and winter. Taking accord of local terrain, infield was the main part of seasonal bare land. The experiment result showed that all-year bare land mainly distributes in northwest Beijing, the joint area of Beijing, Shanxi and Inner Mongolia, especially in Inner Mongolia. Seasonal bare land mainly distributes in northwest and west Beijing, gathering in northwest Hebei, east Shanxi; there are also some ones in Daxing, fangshan, changpin, yanqing, miyun, shunyi, and tongzhou areas of Beijing. These two kind bare lands were all possible contributor to sand storm or sand dust weather in Beijing. Considering wind direction and terrain information of Beijing area, some possible sand source could be found

  7. Bacterial communities involved in soil formation and plant establishment triggered by pyrite bioweathering on arctic moraines.

    Science.gov (United States)

    Mapelli, Francesca; Marasco, Ramona; Rizzi, Agostino; Baldi, Franco; Ventura, Stefano; Daffonchio, Daniele; Borin, Sara

    2011-02-01

    In arctic glacier moraines, bioweathering primed by microbial iron oxidizers creates fertility gradients that accelerate soil development and plant establishment. With the aim of investigating the change of bacterial diversity in a pyrite-weathered gradient, we analyzed the composition of the bacterial communities involved in the process by sequencing 16S rRNA gene libraries from different biological soil crusts (BSC). Bacterial communities in three BSC of different morphology, located within 1 m distance downstream a pyritic conglomerate rock, were significantly diverse. The glacier moraine surrounding the weathered site showed wide phylogenetic diversity and high evenness with 15 represented bacterial classes, dominated by Alphaproteobacteria and pioneer Cyanobacteria colonizers. The bioweathered area showed the lowest diversity indexes and only nine bacterial families, largely dominated by Acidobacteriaceae and Acetobacteraceae typical of acidic environments, in accordance with the low pH of the BSC. In the weathered BSC, iron-oxidizing bacteria were cultivated, with counts decreasing along with the increase of distance from the rock, and nutrient release from the rock was revealed by environmental scanning electron microscopy-energy dispersive X-ray analyses. The vegetated area showed the presence of Actinomycetales, Verrucomicrobiales, Gemmatimonadales, Burkholderiales, and Rhizobiales, denoting a bacterial community typical of developed soils and indicating that the lithoid substrate of the bare moraine was here subjected to an accelerated colonization, driven by iron-oxidizing activity.

  8. Characterizing the Microenvironment Surrounding Phosphorylated Protein Sites

    Institute of Scientific and Technical Information of China (English)

    Shi-Cai Fan; Xue-Gong Zhang

    2005-01-01

    Protein phosphorylation plays an important role in various cellular processes. Due to its high complexity, the mechanism needs to be further studied. In the last few years, many methods have been contributed to this field, but almost all of them investigated the mechanism based on protein sequences around protein sites. In this study, we implement an exploration by characterizing the microenvironment surrounding phosphorylated protein sites with a modified shell model, and obtain some significant properties by the rank-sum test, such as the lack of some classes of residues, atoms, and secondary structures. Furthermore, we find that the depletion of some properties affects protein phosphorylation remarkably. Our results suggest that it is a meaningful direction to explore the mechanism of protein phosphorylation from microenvironment and we expect further findings along with the increasing size of phosphorylation and protein structure data.

  9. Opportunity's Surroundings After Sol 1820 Drive

    Science.gov (United States)

    2009-01-01

    NASA's Mars Exploration Rover Opportunity used its navigation camera to take the images combined into this full-circle view of the rover's surroundings during the 1,820th to 1,822nd Martian days, or sols, of Opportunity's surface mission (March 7 to 9, 2009). South is at the center; north at both ends. The rover had driven 20.6 meters toward the northwest on Sol 1820 before beginning to take the frames in this view. Tracks from that drive recede southwestward. For scale, the distance between the parallel wheel tracks is about 1 meter (about 40 inches). The terrain in this portion of Mars' Meridiani Planum region includes dark-toned sand ripples and small exposures of lighter-toned bedrock. This view is presented as a cylindrical projection with geometric seam correction.

  10. Exploiting Surrounding Text for Retrieving Web Images

    Directory of Open Access Journals (Sweden)

    S. A. Noah

    2008-01-01

    Full Text Available Web documents contain useful textual information that can be exploited for describing images. Research had been focused on representing images by means of its content (low level description such as color, shape and texture, little research had been directed to exploiting such textual information. The aim of this research was to systematically exploit the textual content of HTML documents for automatically indexing and ranking of images embedded in web documents. A heuristic approach for locating and assigning weight surrounding web images and a modified tf.idf weighting scheme was proposed. Precision-recall measures of evaluation had been conducted for ten queries and promising results had been achieved. The proposed approach showed slightly better precision measure as compared to a popular search engine with an average of 0.63 and 0.55 relative precision measures respectively.

  11. The Impact of Nesting Socotra Cormorants on Soil Chemistry and Vegetation in a Large Colony in the United Arab Emirates

    Directory of Open Access Journals (Sweden)

    Taoufik Saleh Ksiksi

    2015-03-01

    Full Text Available Socotra Cormorants (Phalacrocorax nigrogularis are regionally endemic seabirds with restricted distribution. To better understand their nest selection, we assessed vegetation and soil elements in their nesting areas at Siniya Island of United Arab Emirates. Field sampling was done from three areas (2011 nesting area, 2012 nesting area and control area in February and March in 2013. Sampling consisted of vegetation assessment in the field and close-range photography. Ground cover within quadrats was classified into the percent of (1 living cover, (2 dead cover, (3 droppings, (4 bare ground and (5 other. Soil samples were analyzed for thirteen elements. Multivariate stepwise discriminant analysis was performed to determine the importance of the attributes on nest sites. The contribution of Function 1 to the discriminant model was estimated to be 77.4%, whereas Function 2 contributed 22.6% to the discriminant model (P ≤ 0:05. Sites could not be classified adequately using ground cover alone; however, discriminant analysis using soil attributes could better distinguish sites. We noted that Fe and Mn had high discriminant ability in Function 1, whereas Al and Cr showed high discriminant roles for Function 2. The contribution of Function 1 to the model, using soil attributes, was estimated to be 90.7% (P ≤ 0:05. The combination of ground cover and soil attributes did not improve discrimination of nest sites. Furthermore, some soil variables (Ca, Na, Cd and Cr were much higher than normal levels in soil, indicating high transport of marine nutrients to nesting sites, which could detrimentally affect surrounding vegetation.

  12. Application of pyrolysis-gas chromatography/mass spectrometry to study changes in the organic matter of macro- and microaggregates of a Mediterranean soil upon heating

    NARCIS (Netherlands)

    Campo, J.; Nierop, K.G.J.; Cammeraat, E.; Andreu, V.; Rubio, J.L.

    2011-01-01

    The heating effect on the soil organic matter (SOM) of a Mediterranean soil was studied in two fractions (macro- and microaggregates) and in two environments (soil under canopy of Quercus coccifera and bare soil between plants). Samples were heated under laboratory conditions at different temperatur

  13. The potential of cover crops for improving soil function

    Science.gov (United States)

    Stoate, Chris; Crotty, Felicity

    2017-04-01

    Cover crops can be grown over the autumn and winter ensuring green cover throughout the year. They have been described as improving soil structure, reducing soil erosion and potentially even a form of grass weed control. These crops retain nutrients within the plant, potentially making them available for future crops, as well as increasing soil organic matter. Over the last three years, we have investigated how different cover crop regimes affect soil quality. Three separate experiments over each autumn/winter period have investigated how different cover crops affect soil biology, physics and chemistry, with each experiment building on the previous one. There have been significant effects of cover crops on soil structure, as well as significantly lower weed biomass and increased yields in the following crop - in comparison to bare stubble. For example, the effect of drilling the cover crops on soil structure in comparison to a bare stubble control that had not been driven on by machinery was quantified, and over the winter period the soil structure of the cover crop treatments changed, with compaction reduced in the cover crop treatments, whilst the bare stubble control remained unchanged. Weeds were found in significantly lower biomass in the cover crop mixes in comparison to the bare stubble control, and significantly lower weed biomass continued to be found in the following spring oat crop where the cover crops had been, indicating a weed suppressive effect that has a continued legacy in the following crop. The following spring oats have shown similar results in the last two years, with higher yields in the previous cover crop areas compared to the bare stubble controls. Overall, these results are indicating that cover crops have the potential to provide improvements to soil quality, reduce weeds and improve yields. We discuss the economic implications.

  14. Employing UAVs to Acquire Detailed Vegetation and Bare Ground Data for Assessing Rangeland Health

    Science.gov (United States)

    Rango, A.; Laliberte, A.; Herrick, J. E.; Winters, C.

    2007-12-01

    Because of its value as a historical record (extending back to the mid 1930s), aerial photography is an important tool used in many rangeland studies. However, these historical photos are not very useful for detailed analysis of rangeland health because of inadequate spatial resolution and scheduling limitations. These issues are now being resolved by using Unmanned Aerial Vehicles (UAVs) over rangeland study areas. Spatial resolution improvements have been rapid in the last 10 years from the QuickBird satellite through improved aerial photography to the new UAV coverage and have utilized improved sensors and the more simplistic approach of low altitude flights. Our rangeland health experiments have shown that the low altitude UAV digital photography is preferred by rangeland scientists because it allows, for the first time, their identification of vegetation and land surface patterns and patches, gap sizes, bare soil percentages, and vegetation type. This hyperspatial imagery (imagery with a resolution finer than the object of interest) is obtained at about 5cm resolution by flying at an altitude of 150m above the surface of the Jornada Experimental Range in southern New Mexico. Additionally, the UAV provides improved temporal flexibility, such as flights immediately following fires, floods, and other catastrophic disturbances, because the flight capability is located near the study area and the vehicles are under the direct control of the users, eliminating the additional steps associated with budgets and contracts. There are significant challenges to improve the data to make them useful for operational agencies, namely, image distortion with inexpensive, consumer grade digital cameras, difficulty in detecting sufficient ground control points in small scenes (152m by 114m), accuracy of exterior UAV information on X,Y, Z, roll, pitch, and heading, the sheer number of images collected, and developing reliable relationships with ground-based data across a broad

  15. Effects of soil management techniques on soil water erosion in apricot orchards.

    Science.gov (United States)

    Keesstra, Saskia; Pereira, Paulo; Novara, Agata; Brevik, Eric C; Azorin-Molina, Cesar; Parras-Alcántara, Luis; Jordán, Antonio; Cerdà, Artemi

    2016-05-01

    Soil erosion is extreme in Mediterranean orchards due to management impact, high rainfall intensities, steep slopes and erodible parent material. Vall d'Albaida is a traditional fruit production area which, due to the Mediterranean climate and marly soils, produces sweet fruits. However, these highly productive soils are left bare under the prevailing land management and marly soils are vulnerable to soil water erosion when left bare. In this paper we study the impact of different agricultural land management strategies on soil properties (bulk density, soil organic matter, soil moisture), soil water erosion and runoff, by means of simulated rainfall experiments and soil analyses. Three representative land managements (tillage/herbicide/covered with vegetation) were selected, where 20 paired plots (60 plots) were established to determine soil losses and runoff. The simulated rainfall was carried out at 55mmh(-1) in the summer of 2013 (erosion were significantly higher in herbicide treated plots compared to the others. Runoff sediment concentration was significantly higher in tilled plots. The lowest values were identified in covered plots. Overall, tillage, but especially herbicide treatment, decreased vegetation cover, soil moisture, soil organic matter, and increased bulk density, runoff coefficient, total runoff, sediment yield and soil erosion. Soil erosion was extremely high in herbicide plots with 0.91Mgha(-1)h(-1) of soil lost; in the tilled fields erosion rates were lower with 0.51Mgha(-1)h(-1). Covered soil showed an erosion rate of 0.02Mgha(-1)h(-1). These results showed that agricultural management influenced water and sediment dynamics and that tillage and herbicide treatment should be avoided.

  16. 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.

  17. The lithosphere-asthenosphere Italy and surroundings

    CERN Document Server

    Panza, G F; Chimera, G; Pontevivo, A; Raykova, R

    2003-01-01

    The velocity-depth distribution of the lithosphere-asthenosphere in the Italian region and surroundings is imaged, with a lateral resolution of about 100 km, by surface wave velocity tomography and non-linear inversion. Maps of the Moho depth, of the thickness of the lithosphere and of the shear-wave velocities, down to depths of 200 km and more, are constructed. A mantle wedge, identified in the uppermost mantle along the Apennines and the Calabrian Arc, underlies the principal recent volcanoes, and partial melting can be relevant in this part of the uppermost mantle. In Calabria a lithospheric doubling is seen, in connection with the subduction of the Ionian lithosphere. The asthenosphere is shallow in the Southern Tyrrhenian Sea. High velocity bodies, cutting the asthenosphere, outline the Adria-lonian subduction in the Tyrrhenian Sea and the deep-reaching lithospheric root in the Western Alps. Less deep lithospheric roots are seen in the Central Apennines. The lithosphere-asthenosphere properties delineat...

  18. The lithosphere-asthenosphere: Italy and surroundings

    Institute of Scientific and Technical Information of China (English)

    GiulianoF.Panza; AntonellaPontevivo; GiordanoChimera; RenetaRaykova; AbdelkrimAoudia

    2003-01-01

    The velocity-depth distribution of the lithosphere-asthenosphere in the Italian region and surroundings is imaged, with a lateral resolution of about 100 km, by sur-face wave velocity tomography and non-linear inversion.Maps of the Moho depth, of the thickness of the lithos-phere and of the shear-wave velocities, down to depths of 200 km and more, are constructed. A mantle wedge, iden-tified in the uppermost mantle along the Apennines and the Calabrian Arc, underlies the prmctpat recent votca-noes, and partial melting can be relevant in this part of the uppermost mantle. In Calabria, a lithospheric dou-bling is seen, in connection with the subduction of the Ionian lithosphere. The asthenosphere is shallow in the Southern Tyrrhenian Sea. High velocity bodies, cutting the asthenosphere, outline the Adria-lonian subduction in the Tyrrhenian Sea and the deep-reaching lithospheric root in the Western Alps. Less deep lithospheric roots are seen in the Central Apennines. The lithosphere-asthenos-phere properties delineate a differentiation between the northern and the southern sectors of the Adriatic Sea,likely attesting the fragmentation of Adria.

  19. Preliminary design of surrounding heliostat fields

    Energy Technology Data Exchange (ETDEWEB)

    Collado, Francisco J. [Zaragoza University, Dpto. de Ingenieria Mecanica, CPS-B, Maria de Luna 3, 50018 Zaragoza (Spain)

    2009-05-15

    Recently, the author has shown elsewhere a simplified model that allows quick evaluations of the annual overall energy collected by a surrounding heliostat field. This model is the combination of an analytical flux density function produced by a heliostat, developed by the own author, and an optimized mirror density distribution developed by University of Houston for the Solar One Project. As main conclusion of this previous work, it was recognized that such pseudo-continuous simplified model should not substitute much more accurate discrete evaluations, which manage thousands of individual heliostat coordinates. Here in this work, the difficulty of generating a preliminary discrete layout of a large number of heliostats is addressed. The main novelty is the direct definition of thousands of heliostat coordinates through basically two parameters i.e. a simplified blocking factor and an additional security distance. Such procedure, which was formerly theoretically suggested by the author, is put into practice here, showing examples and commenting their problems and advantages. Getting a previous set of thousands of heliostat coordinates would be a major first step in the complex process of designing solar power tower (SPT). (author)

  20. Soil vulnerability for cesium transfer.

    Science.gov (United States)

    Vandenhove, Hildegarde; Sweeck, Lieve

    2011-07-01

    The recent events at the Fukushima Daiichi nuclear power plant in Japan have raised questions about the accumulation of radionuclides in soils and the possible impacts on agriculture surrounding nuclear power plants. This article summarizes the knowledge gained after the nuclear power plant accident in Chernobyl, Ukraine, on how soil parameters influence soil vulnerability for radiocesium bioavailability, discusses some potential agrochemical countermeasures, and presents some predictions of radiocesium crop concentrations for areas affected by the Fukushima accident.

  1. The Comparison of Bare Sclera and Rotational Flap Methods in Primary Pterygium Surgery

    Directory of Open Access Journals (Sweden)

    N. Bazazi

    2005-01-01

    Full Text Available The objective of this study was the comparison of Bare Sclera and Rotational Flap methods in primary pterygium surgery. This study was retrospective Cohort and studied population were 80 patients (40 patients in each group with primary pterygium in stage II and III operated in Hamadan Emam Khomeini hospital , during 2001-2003. All of the patients followed up 48 hours , 1 week , 1,3 and 6 months after operative surgery. In this study , complications and recurrences of both methods (Bare Sclera and Rotational Flap were compared and the results were as follows : Recurrence rate in Bare Sclera method was 22.5% and in rotational flap method 11.1% , that obtained no significant relationship between two groups. Also there was not significant difference in complications.

  2. Patches of bare ground as a staple commodity for declining ground-foraging insectivorous farmland birds.

    Science.gov (United States)

    Schaub, Michael; Martinez, Nicolas; Tagmann-Ioset, Aline; Weisshaupt, Nadja; Maurer, Melanie L; Reichlin, Thomas S; Abadi, Fitsum; Zbinden, Niklaus; Jenni, Lukas; Arlettaz, Raphaël

    2010-10-06

    Conceived to combat widescale biodiversity erosion in farmland, agri-environment schemes have largely failed to deliver their promises despite massive financial support. While several common species have shown to react positively to existing measures, rare species have continued to decline in most European countries. Of particular concern is the status of insectivorous farmland birds that forage on the ground. We modelled the foraging habitat preferences of four declining insectivorous bird species (hoopoe, wryneck, woodlark, common redstart) inhabiting fruit tree plantations, orchards and vineyards. All species preferred foraging in habitat mosaics consisting of patches of grass and bare ground, with an optimal, species-specific bare ground coverage of 30-70% at the foraging patch scale. In the study areas, birds thrived in intensively cultivated farmland where such ground vegetation mosaics existed. Not promoted by conventional agri-environment schemes until now, patches of bare ground should be implemented throughout grassland in order to prevent further decline of insectivorous farmland birds.

  3. Impact of the soil hydrology scheme on simulated soil moisture memory in a GCM

    Science.gov (United States)

    Hagemann, Stefan; Stacke, Tobias

    2013-04-01

    Soil moisture-atmosphere feedback effects play an important role in several regions of the globe. For some of these regions, soil moisture memory may contribute significantly to the development of the regional climate. Identifying those regions can help to improve predictability in seasonal to decadal climate forecasts. The present study investigates how different setups of the soil hydrology scheme affect soil moisture memory simulated by the global climate model of the Max Planck Institute for Meteorology (MPI-M), ECHAM6/JSBACH. First, the standard setup applied for the CMIP5 exercise is used, in which soil water is represented by a single soil moisture reservoir. Second, a new five soil layer hydrology scheme is utilized where the previous bucket soil moisture now corresponds to the root zone soil moisture. In the standard setup, transpiration may access the whole soil moisture that is exceeding the wilting point over vegetated areas. However, in the five layer scheme, soil water below the root zone cannot be accessed by transpiration directly, but only be transported upwards into the root zone by diffusion following the Richard's equation. Thus, this below the root zone, which is not present in the standard setup, can act as buffer in the transition between wet and dry periods. A second notable difference between the two setups is the formulation of bare soil evaporation. In the standard setup, it may only occur if the whole soil moisture bucket is almost completely saturated, while in the new setup, it depends only on the saturation of the upper most soil layer. As the latter is much thinner than the root zone (bucket), bare soil evaporation can occur more frequently, especially after rainfall events. For the second setup, two further variants are considered: one where the bare soil evaporation was modified and one where a new parameter dataset of soil water holding capacities was used. Soil moisture memory of the different setups will be analysed from global

  4. Estimating Vegetation Height and Bare-Earth Topography from SRTM Data using Fourier Spectral Decomposition

    Science.gov (United States)

    Gangodagamage, C.; Liu, D.; Alsdorf, D.

    2010-12-01

    In this study, LiDAR vegetation topography (bare-earth + vegetation height), LiDAR bare-earth topography, the National Elevation Data (NED) set, and Shuttle Radar Terrain Mission (SRTM) measurements are used to develop a statistical model to explore the possibility of extracting vegetation height measurements and accurate high resolution bare-earth topography from SRTM data. The key innovation is to obtain the statistical signature of the vegetation height measurements in the Fourier domain by taking advantage of the well-known linearity in additive properties of the Fourier transform. We demonstrate that the power-law relationship, P(k) α k^(-β), as shown by the bare-earth topography, breaks down approximately at a cross-over wavenumber, k=k_c, due to the vegetation height effect using four different topographic and vegetation study locations in the United States. We document that the vegetation effect mainly dominates the high-frequency contents of the vegetation topography from 2-180 m, 1-60 m, and 1-70 m for the South Fork Eel River, California; Flathead Lake, Montana; and Tenderfoot Creek, Montana, LiDAR data, respectively, and from 1-240 m for 30 m SRTM data for the Jesup, Georgia site. Finally, we demonstrate our ability to obtain a high resolution bare-earth topography with RMSE of 9.6 m, 2.2 m, and 2.9 m and vegetation height with RMSE of 11.0 m (11% error), 4.5 m (12% error), and 1.6 m (8% error) for LiDAR data study sites, whereas for the SRTM data, bare-earth topography and vegetation height are obtained with RMSE values of 5.4 m and 3.1 m, respectively, for the Jesup site. Model Vegetation height

  5. Criticality analysis for weapon disassembly at the Pantex Plant - part I: Bare pits

    Energy Technology Data Exchange (ETDEWEB)

    Knief, R.A. [Ogden Environmental & Energy Services, Albuquerque, NM (United States)

    1997-06-01

    This paper briefly describes criticality investigations for weapon assembly and dismantlement at the Pantex Plant. Results are summarized for calculations performed for safety analyses, radiological hazards assessments, and a study to justify the criticality alarm exemption. Pits and pits in containers were modeled in their most reactive configuration. Criticality calculations were performed with the KENO and MCNP code packages. Configurations involving bare pits were subcritical by a substantial amount even with very conservative model assumptions. Thus, it is concluded that a critical configuration involving the bare pits is not credible.

  6. Bare PCB inspection system with SV-GMR sensor eddy-current testing probe

    OpenAIRE

    Chomsuwan, K.; Yamada, Sotoshi; Iwahara, Masayoshi

    2007-01-01

    This paper describes bare printed circuit board (PCB) inspection based on eddy-current testing (ECT) technique with high scanning speed. A high-frequency ECT probe composed of a meander coil as an exciting coil and the spin-valve giant magnetoresistance (SV-GMR) sensor was fabricated and is proposed. The ECT probe was designed based on crack inspection over flat surface, especially suitable for microdefect detection on high-density bare PCB. The ECT signal detected by the SV-GMR sensor was ac...

  7. Bare Fiber Bragg Gratings embedded into concrete buffer Supercontainer concept for nuclear waste storage

    Energy Technology Data Exchange (ETDEWEB)

    Kinet, Damien; Chah, Karima; Megret, Patrice; Caucheteur, Christophe [Electromagnetism and Telecommunications Department of the University of Mons, 31 Boulevard Dolez, 7000 Mons, (Belgium); Gusarov, Andrei [Belgian Nuclear Research Center, Boeretang 200, 2400 Mol, (Belgium); Faustov, Alexey [Belgian Nuclear Research Center, Boeretang 200, 2400 Mol, (Belgium); Electromagnetisme and Telecommunication Department of the University of Mons, 31 Boulevard Dolez, 7000 Mons, (Belgium); Areias, Lou [Mechanics of Materials and Constructions Department of the Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussels, (Belgium); European Underground Research Infrastructure for Disposal of nuclear waste In Clay Environment, Boeretang 200, 2400 Mol, (Belgium)

    2015-07-01

    We present the preliminary results obtained with bare fiber Bragg grating-based sensors embedded into half-scale Belgian Supercontainer concept. Being temperature and strain sensitive, some sensors were placed into aluminum tubes to monitor only temperature and results were compared with thermocouples data. The utility of using bare fiber Bragg gratings, knowing that these ones are very fragile, is to have a direct contact between the high alkaline environment of the concrete and silica fibers and to determine its impact over a very long time. (authors)

  8. Correlations between soil microbial and physicochemical variations in a rice paddy: implications for assessing soil health

    Indian Academy of Sciences (India)

    Ryoichi Doi; Senaratne Leelananda Ranamukhaarachchi

    2009-12-01

    This study was conducted to test the hypothesis that spatial variations in soil microbial variables in a Thai rice paddy are accurately described by multivariate profiles of the soil bacterial communities. We found that community-level physiological profiles of soil bacterial communities could better describe the population density of Rhizoctonia solani in soil than the physicochemical profiles do. However, soil dehydrogenase levels were closely correlated with soil fertility ( < 0.05), and these were better described by the physicochemical profiles. Hence, the hypothesis was rejected, and we suspect that soil microbial variables react differently to the same physicochemical changes. The average population density of R. solani (35 colony-forming units/g dry soil) was relatively high in the soil we studied, and the soil fertility was found to be among the poorest in Thailand. The soil quality was comparable to the most degraded bare ground soil in an adjacent bioreserve in terms of Shannon diversity index based on the community-level physiological profile as well as values of soil fertility indices. Overall, the soil microbial and physicochemical indicators showed that the paddy soil needs to be supplemented with soil nutrients. Otherwise, R. solani may cause a significant reduction in rice production.

  9. Mercury Content and Pollution Assessment of Soil and Cabbage Surrounding Yangshuo Pb-Zn Mining District in Guangxi%广西阳朔铅锌矿周边土壤和白菜汞含量及污染评价

    Institute of Scientific and Technical Information of China (English)

    莫福金; 钱建平; 王远炜; 张藜

    2016-01-01

    Yangshuo Pb-Zn mine is a relatively large mine in Guangxi. The article tries to understand the mercury pollution in soil and cabbage, as well as the transition and transform rule of mercury in soil-vegetables system. Investigation and research about the mercury content distribution and mercury pollution of soil and cabbage in the sourrouding farming area and residential area of Yangshuo Pb-Zn mine was done, in order to provide a scientific basis for mercury pollution prevention and remediation. In the research, 66 soil samples and 35 cabbage samples were collected in farming area of the downstream of Pb-Zn mine, 38 soil samples and 20 cabbage samples were collected in control farming area; 17 soil samples were collected in residential area. All soil and plant samples were digested by MDS-2003F-type pressure-controlled microwave digestion system and were analyzed with atomic fluorescence mercury analyzer. The result showed that the mercury concentration in the downstream arming area of Pb-Zn mine was (0.5674±0.2683) mg·kg-1, the mercury concentration in control farming area was (0.1471±0.0395) mg·kg-1, the mercury concentration in residential area was (0.1880±0.0972) mg·kg-1, which is 7.99, 2.07, 2.65 times higher compared with the natural content (0.071 mg·kg-1) of soil Mercury in some areas. In the downstream farming area of Pb-Zn mine, the soil mercury levels is decreasing when the distance from the mine is increasing. In the downstream farming area of Pb-Zn mine, the average mercury concentration at cabbage root was 27600 ng·kg-1, the average mercury concentration at Cabbage stem was 7100 ng·kg-1, the average mercury concentration at Cabbage leaf was 19300 ng·kg-1; in the control farming area, the average mercury concentration at cabbage root was 12500 ng·kg-1, the average mercury concentration at Cabbage stem was 4800 ng·kg-1, the average mercury concentration at Cabbage leaf was 10000 ng·kg-1. Cabbage mercury distribution characteristics is

  10. Soil dehydrogenase in a land degradation-rehabilitation gradient: observations from a savanna site with a wet/dry seasonal cycle.

    Science.gov (United States)

    Doi, Ryoichi; Ranamukhaarachchi, Senaratne Leelananda

    2009-01-01

    Soil dehydrogenase activity is a good indicator of overall microbial activity in soil, and it can serve as a good indicator of soil condition. However, seasonal changes in soil moisture content may have an effect on soil dehydrogenase activity, making an accurate assessment of soil condition difficult. In this study, we attempted to determine the significance of soil dehydrogenase activity for assessing soil condition, and we attempted to find a way to account for the influence of soil moisture content on soil dehydrogenase activity.' Soils were sampled in dry evergreen forest (original vegetation), bare ground (severely degraded) and Acacia plantation plots established on bare ground in 1986 and 1987 in Sakaerat, Thailand. Soil physico-chemical characteristics and dehydrogenase activity in the Acacia plantation soil had few differences from those in the evergreen forest soil. Soil dehydrogenase activity varied significantly between the bare ground and the forests regardless of the season (wet or dry), while the season did not produce a significant variation in soil dehydrogenase activity, as determined by repeated measures analysis of variance (p=0.077). The physico-chemical data provided the first principal component as a good measure of soil fertility. Values of soil dehydrogenase activity significantly correlated to scores of the soil samples of the first principal component (R=0.787, pThailand.

  11. Seasonal variation in soil seed bank size and species composition of selected habitat types in Maputaland, South Africa

    Directory of Open Access Journals (Sweden)

    M. J. S. Kellerman

    2007-12-01

    Full Text Available Seasonal variation in seed bank size and species composition of five selected habitat types within the Tembe Elephant Park. South Africa, was investigated. At three-month intervals, soil samples were randomly collected from five different habitat types: a, Licuati forest; b, Licuati thicket; c, a bare or sparsely vegetated zone surrounding the forest edge, referred to as the forest/grassland ecotone; d, grassland; and e, open woodland. Most species in the seed bank flora were either grasses, sedges, or forbs, with hardly any evidence of woody species. The Licuati forest and thicket soils produced the lowest seed densities in all seasons.  Licuati forest and grassland seed banks showed a two-fold seasonal variation in size, those of the Licuati thicket and woodland a three-fold variation in size, whereas the forest/grassland ecotone maintained a relatively large seed bank all year round. The woodland seed bank had the highest species richness, whereas the Licuati forest and thicket soils were poor in species. Generally, it was found that the greatest correspondence in species composition was between the Licuati forest and thicket, as well as the forest/grassland ecotone and grassland seed bank floras.

  12. Drug-eluting versus bare-metal stents in large coronary arteries

    DEFF Research Database (Denmark)

    Kaiser, Christoph; Galatius, Soeren; Erne, Paul

    2010-01-01

    Recent data have suggested that patients with coronary disease in large arteries are at increased risk for late cardiac events after percutaneous intervention with first-generation drug-eluting stents, as compared with bare-metal stents. We sought to confirm this observation and to assess whether...

  13. TARGET EXCITATION IN BARE ION XE/AR COLLISIONS STUDIED BY ELECTRON TARGET ION COINCIDENCES

    NARCIS (Netherlands)

    DENIJS, G; HOEKSTRA, R; MORGENSTERN, R

    We present electron spectra resulting from collisions of bare ions N-15(7+) and C-13(6+) on Ar and the charge state distribution of target ions resulting from C-13(6+)-Xe collisions. From both type of experiments we find evidence that electron capture accompanied by target excitation is an important

  14. Comparative measurements with seven rainfall simulators on uniform bare fallow land

    NARCIS (Netherlands)

    Iserloh, T.; Ries, J.B.; Cerda, A.; Echeverria, M.T.; Fister, W.; Geissler, C.; Kuhn, N.J.; Leon, F.J.; Peters, P.; Schindewolf, M.; Schmidt, J.; Scholten, T.; Seeger, K.M.

    2013-01-01

    To assess the influence of rainfall simulator type and plot dimensions on runoff and erosion, seven small portable rainfall simulators from Freiberg, Tubingen, Trier (all Germany), Valencia, Zaragoza (both Spain), Basel (Switzerland) and Wageningen (the Netherlands) were compared on a prepared bare

  15. A new notion of soundness in bare public-key model

    Institute of Scientific and Technical Information of China (English)

    ZHAO Yunlei; ZHU Hong

    2003-01-01

    A new notion of soundness in bare public-key (BPK) model is presented. This new notion just lies in between one-time soundness and sequential soundness and its reasonableness is justified in the context of resettable zero-knowledge when resettable zero-knowledge prover is implemented by smart card.

  16. Graph segmentation and support vector machines for bare earth classification from lidar

    Science.gov (United States)

    Shorter, Nicholas S.; Smith, O'Neil; Smith, Philip; Rahmes, Mark

    2014-06-01

    A novel approach using a support vector machine (SVM) is proposed to classify bare earth points in LiDAR point clouds. Using graph based segmentation, the LiDAR point cloud is segmented into a set of topological components. Several features establishing relationships from those components to their neighboring components are formulated. The SVM is then trained on the segment features to establish a model for the classification of bare earth and non bare earth points. Quantitative results are presented for training and testing the proposed SVM classifier on the ISPRS data set. Using the ISPRS data set as a training set, qualitative results are presented by testing the proposed SVM classifier on data downloaded from Open Topography; which covers a variety of different landscapes and building structures in Frazier Park, California. Despite the data being captured from different sensors, and collected from scenes with different terrain types and building structures, the results shown were processed with no parameter changes. Furthermore, a confidence value is returned indicating how well the unforeseen data fits the SVM's trained model for bare earth recognition.

  17. Patients' perceptions of doctors' clothing: should we really be 'bare below the elbow'?

    Science.gov (United States)

    Bond, L; Clamp, P J; Gray, K; Van Dam, V

    2010-09-01

    In September 2007, the Department of Health published Uniforms and Workwear: an Evidence Base for Guiding Local Policy. Following this, most National Health Service trusts imposed a 'bare below the elbow' dress code policy, with clinical staff asked to remove ties, wristwatches and hand jewellery and to wear short-sleeved tops. There is currently no evidence linking dress code to the transmission of hospital-acquired infection. We designed the current survey to assess patients' perceptions of doctors' appearance, with specific reference to the 'bare below the elbow' policy. A questionnaire showing photographs of a doctor in three different types of attire ('scrubs', formal attire and 'bare below the elbow') were used to gather responses from 80 in-patients and 80 out-patients in the ENT department. Patients were asked which outfit they felt was the most hygienic, the most professional and the easiest identification of the person as a doctor. They were also asked to indicate their overall preference. Formal attire was considered most professional and the easiest identification that the person was a doctor. Scrubs were considered most hygienic. Respondents' overall preference was divided between scrubs and formal clothes. 'Bare below the elbow' attire received the lowest votes in all categories. This finding raises significant questions about the Department of Health policy in question. The authors suggest that an alternative policy should be considered, with scrubs worn for in-patient situations and formal attire during out-patient encounters.

  18. EAARL-B coastal topography: Chandeleur Islands, Louisiana, 2012: seamless (bare earth and submerged)

    Science.gov (United States)

    Wright, C. Wayne; Klipp, Emily S.; Kranenburg, Christine J.; Troche, Rodolfo J.; Fredericks, Alexandra M.; Masessa, Melanie L.; Nagle, David B.

    2015-01-01

    These remotely sensed, geographically referenced elevation measurements of light detection and ranging (lidar)-derived seamless (bare-earth and submerged) topography datasets were produced by the U.S. Geological Survey (USGS), St. Petersburg Coastal and Marine Science Center, St. Petersburg, Florida.

  19. Bare Forms and Lexical Insertions in Code-Switching: A Processing-Based Account

    Science.gov (United States)

    Owens, Jonathan

    2005-01-01

    Bare forms (or [slashed O] forms), uninflected lexical L2 insertions in contexts where the matrix language expects morphological marking, have been recognized as an anomaly in different approaches to code-switching. Myers-Scotton (1997, 2002) has explained their existence in terms of structural incongruity between the matrix and embedded…

  20. Bare Pedagogy and the Scourge of Neoliberalism: Rethinking Higher Education as a Democratic Public Sphere

    Science.gov (United States)

    Giroux, Henry A.

    2010-01-01

    A new form of bare pedagogy is emerging in higher education focused on market-driven competitiveness and even militaristic goal-setting, while critical pedagogy, with its emphasis on the hard work of critical analysis, moral judgments, and social responsibility (critical pedagogy that goes to the very heart of what it means to address real…

  1. Characterization of diamond film and bare metal photocathodes as a function of temperature and surface preparation

    Energy Technology Data Exchange (ETDEWEB)

    Shurter, R.P.; Moir, D.C.; Devlin, D.J.

    1996-07-01

    High current photocathodes using bare metal and polycrystalline diamond films illuminated by ultraviolet lasers are being developed at Los Alamos for use in a new generation of linear induction accelerators. These photocathodes must be able to produce multiple 60 ns pulses separated by several to tens of nanoseconds. The vacuum environment in which the photocathodes must operate is 10{sup -5} torr.

  2. EAARL Coastal Topography—Northern Assateague Island National Seashore, Maryland and Virginia, 2003: Bare earth

    Science.gov (United States)

    Kranenburg, Christine; Fredericks, Alexandra M.; Nagle, David B.

    2017-01-01

    These datasets, prepared by the U.S. Geological Survey St. Petersburg Coastal and Marine Science Center in collaboration with the National Park Service, provide lidar-derived bare-earth topography for Northern Assateague Island National Seashore, Maryland and Virginia. Elevation measurements were acquired by the Experimental Advanced Airborne Research Lidar (EAARL) during February 2003.

  3. Bare Quark Stars or Naked Neutron Stars: The Case of RX J1856.5-3754

    CERN Document Server

    Turolla, R; Drake, J J; Turolla, Roberto; Zane, Silvia; Drake, Jeremy J.

    2004-01-01

    In a cool neutron star (T 10^13 G), a phase transition may occur in the outermost layers. As a consequence the neutron star becomes `bare', i.e. no gaseous atmosphere sits on the top of the crust. The surface of cooling, bare neutron stars not necessary gives off blackbody radiation because of the strong suppression in the emissivity at energies below the electron plasma frequency \\omega_p. Since \\omega_p~1 keV under the conditions typical of the dense electron gas in the condensate, the emission from a T~100 eV bare neutron star will be substantially depressed with respect to that of a perfect Planckian radiator at most energies. Here we present a detailed analysis of the emission properties of a bare neutron star. In particular, we derive the surface emissivity for a Fe composition in a range of magnetic fields and temperatures representative of cooling isolated neutron stars, like RX J1856.5-3754. We find that the emitted spectrum is strongly dependent on the electron conductivity in the solid surface lay...

  4. Drug-eluting versus bare-metal stents in large coronary arteries

    DEFF Research Database (Denmark)

    Kaiser, Christoph; Galatius, Soeren; Erne, Paul

    2010-01-01

    Recent data have suggested that patients with coronary disease in large arteries are at increased risk for late cardiac events after percutaneous intervention with first-generation drug-eluting stents, as compared with bare-metal stents. We sought to confirm this observation and to assess whether...... this increase in risk was also seen with second-generation drug-eluting stents....

  5. Long-Term Safety of Drug-Eluting and Bare-Metal Stents

    DEFF Research Database (Denmark)

    Palmerini, Tullio; Benedetto, Umberto; Biondi-Zoccai, Giuseppe;

    2015-01-01

    BACKGROUND: Previous meta-analyses have investigated the relative safety and efficacy profiles of different types of drug-eluting stents (DES) and bare-metal stents (BMS); however, most prior trials in these meta-analyses reported follow-up to only 1 year, and as such, the relative long-term safe...

  6. Introducing the Notion of Bare and Effective Mass via Newton's Second Law of Motion

    Science.gov (United States)

    Pinto, Marcus Benghi

    2007-01-01

    The concepts of bare and effective mass are widely used within modern physics. Their meaning is discussed in advanced undergraduate and graduate courses such as solid state physics, nuclear physics and quantum field theory. Here I discuss how these concepts may be introduced together with the discussion of Newton's second law of motion. The…

  7. Drug-eluting stents versus bare-metal stents for acute coronary syndrome

    DEFF Research Database (Denmark)

    Feinberg, Joshua; Nielsen, Emil Eik; Greenhalgh, Janette

    2017-01-01

    not included all relevant randomised clinical trials. OBJECTIVES: To assess the benefits and harms of drug-eluting stents versus bare-metal stents in people with acute coronary syndrome. SEARCH METHODS: We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, LILACS, SCI-EXPANDED...

  8. Analyses of protein corona on bare and silica-coated gold nanorods against four mammalian cells.

    Science.gov (United States)

    Das, Minakshi; Yi, Dong Kee; An, Seong Soo A

    2015-01-01

    The purpose of this study was to investigate the mechanisms responsible for the toxic effects of gold nanorods (AuNRs). Here, a comprehensive study was performed by examining the effects of bare (uncoated) AuNRs and AuNRs functionalized with silica (SiO2-AuNRs) against various mammalian cell lines, including cervical cancer cells, fibroblast cells, human umbilical vein endothelial cells, and neuroblastoma cells. The interactions between AuNRs and mammalian cells were investigated with cell viability and mortality assays. Dihydrorhodamine-123 assay was carried out for evaluating reactive oxygen species (ROS) generation, along with mass spectroscopy analysis for determining the composition of the protein corona. Our results suggest that even the lowest concentrations of AuNRs (0.7 μg/mL) induced ROS production leading to cell mortality. On the other hand, cellular viability and ROS production were maintained even at a higher concentration of SiO2-coated AuNRs (12 μg/mL). The increased production of ROS by AuNRs seemed to cause the toxicity observed in all four mammalian cell types. The protein corona on the bare AuNRs did not appear to reduce ROS generation; however, different compositions of the protein corona on bare and SiO2-coated AuNRs may affect cellular behavior differently. Therefore, it was determined that SiO2-coated AuNRs would be more advantageous than bare AuNRs for cellular applications.

  9. Impacts of Artificial Reefs on Surrounding Ecosystems

    Science.gov (United States)

    Manoukian, Sarine

    Artificial reefs are becoming a popular biological and management component in shallow water environments characterized by soft seabed, representing both important marine habitats and tools to manage coastal fisheries and resources. An artificial reef in the marine environment acts as an open system with exchange of material and energy, altering the physical and biological characteristics of the surrounding area. Reef stability will depend on the balance of scour, settlement, and burial resulting from ocean conditions over time. Because of the unstable nature of sediments, they require a detailed and systematic investigation. Acoustic systems like high-frequency multibeam sonar are efficient tools in monitoring the environmental evolution around artificial reefs, whereas water turbidity can limit visual dive and ROV inspections. A high-frequency multibeam echo sounder offers the potential of detecting fine-scale distribution of reef units, providing an unprecedented level of resolution, coverage, and spatial definition. How do artificial reefs change over time in relation to the coastal processes? How accurately does multibeam technology map different typologies of artificial modules of known size and shape? How do artificial reefs affect fish school behavior? What are the limitations of multibeam technology for investigating fish school distribution as well as spatial and temporal changes? This study addresses the above questions and presents results of a new approach for artificial reef seafloor mapping over time, based upon an integrated analysis of multibeam swath bathymetry data and geoscientific information (backscatter data analysis, SCUBA observations, physical oceanographic data, and previous findings on the geology and sedimentation processes, integrated with unpublished data) from Senigallia artificial reef, northwestern Adriatic Sea (Italy) and St. Petersburg Beach Reef, west-central Florida continental shelf. A new approach for observation of fish

  10. Validity of arthroscopic measurement of glenoid bone loss using the bare spot

    Directory of Open Access Journals (Sweden)

    Miyatake K

    2014-03-01

    Full Text Available Katsutoshi Miyatake, Yoshitsugu Takeda, Koji Fujii, Tomoya Takasago, Toshiyuki Iwame Department of Orthopaedic Surgery, Tokushima Red Cross Hospital, Komatsushima, Tokushima, Japan Purpose: Our aim was to test the validity of using the bare spot method to quantify glenoid bone loss arthroscopically in patients with shoulder instability. Methods: Twenty-seven patients with no evidence of instability (18 males, nine females; mean age 59.1 years were evaluated arthroscopically to assess whether the bare spot is consistently located at the center of the inferior glenoid. Another 40 patients with glenohumeral anterior instability who underwent shoulder arthroscopy (30 males, ten females; mean age 25.9 years were evaluated for glenoid bone loss with preoperative three-dimensional computed tomography (3D-CT and arthroscopic examination. In patients without instability, the distances from the bare spot of the inferior glenoid to the anterior (Da and posterior (Dp glenoid rim were measured arthroscopically. In patients with instability, we compared the percentage glenoid bone loss calculated using CT versus arthroscopic measurements. Results: Among patients without instability, the bare spot could not be identified in three of 27 patients. Da (9.5±1.2 mm was smaller than Dp (10.1±1.5 mm, but it was not significantly different. However, only 55% of glenoids showed less than 1 mm of difference between Da and Dp, and 18% showed more than 2 mm difference in length. The bare spot could not be identified in five of 40 patients with instability. Pearson's correlation coefficient showed significant (P<0.001 and strong (R2=0.63 correlation in percentage glenoid bone loss between the 3D-CT and arthroscopy method measurements. However, in ten shoulders (29%, the difference in percentage glenoid bone loss between 3D-CT and arthroscopic measurements was greater than 5%. Conclusion: The bare spot was not consistently located at the center of the inferior glenoid

  11. Niche filtering of bacteria in soil and rock habitats of the Colorado Plateau Desert, Utah, USA

    Directory of Open Access Journals (Sweden)

    Kevin Lee

    2016-09-01

    Full Text Available A common feature of microbial colonisation in deserts is biological soil crusts, and these comprise a complex community dominated by cyanobacteria. Rock substrates, particularly sandstone, are also colonised by microbial communities. These are separated by bare sandy soil that also supports microbial colonisation. Here we report a high-throughput sequencing study of biological soil crust and cryptoendolith plus adjacent bare soil communities in the Colorado Plateau Desert, Utah, USA. Bare soils supported a community with low levels of recoverable DNA and high evenness, whilst biological soil crust yielded relatively high recoverable DNA, and reduced evenness compared to bare soil due to specialized crust taxa. The cryptoendolithic community displayed the greatest evenness but the lowest diversity, reflecting the highly specialised nature of these communities. A strong substrate-dependent pattern of community assembly was observed, and in particular cyanobacterial taxa were distinct. Soils were virtually devoid of photoautotrophic signatures, biological soil crust was dominated by a closely related group of Microcoleus/Phormidium taxa, whilst cryptoendolithic colonisation in sandstone supported almost exclusively a single genus, Chroococcidiiopsis. We interpret this as strong evidence for niche filtering of taxa in communities. Local inter-niche recruitment of photoautotrophs may therefore be limited and so communities likely depend significantly on cyanobacterial recruitment from distant sources of similar substrate. We discuss the implication of this finding in terms of conservation and management of desert microbiota.

  12. Spatial distribution of the radon concentration in soil and subterranean water in the Nuclear Center of Mexico and its surrounding using a geographical information system; Distribucion espacial de la concentracion de radon en suelo y agua subterranea en el Centro Nuclear de Mexico y sus alrededores utilizando un sistema de informacion geografica

    Energy Technology Data Exchange (ETDEWEB)

    Cardenas, S.; Pena, P.; Lopez, M.B.E.; Balcazar, M. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico); Madrigal, D. [UAEM, Facultad de Geografia, 50000 Toluca, estado de Mexico (Mexico)

    2003-07-01

    The radon concentration in soil of the Nuclear Center of Mexico using solid detectors of nuclear traces (LR 115, type ll) and in water of two aquifers of the Asuncion Tepexoyuca, by means of the liquid scintillation technique it was determined; both places located in the Ocoyoacac municipality, Estado de Mexico. The analysis of spatial distribution it was supported by means of a Geographic Information System. The results of the radon concentration in soil, they registered an average of 2. 64 kBq m{sup -3} in the study area, the more high average value it was of 5. 25 kBq m{sup -3} in the station 12-ZM (Military Area) and the minimum value was of 0. 54 kBq m{sup -3} in the point 7-CO (Dining room). In the radon concentration in water of La Perita it was observed an average value 0.52 Bq L{sup -1} and in El Tunel it was of 0.7 Bq L{sup -1}. (Author)

  13. Estimation of Soil Erosion Rates in Oil Palm Plantation with Different Land Cover

    Science.gov (United States)

    Sahat, S.; Yusop, Z.; Askari, M.; Ziegler, A. D.

    2016-07-01

    Soil losses from hill slopes in oil palm plantation in Sedenak Estate, Johor were measured using runoff plot and rainfall simulator. The plot was designed to be removable but the size was fixed at 8 x 3.75m. Four types of surface covers were investigated for the plots, i.e. half bare soil and half grass cover (HGC), half bare soil and half dry frond (HDF), fully grass cover (FG), and fully bare soil (BS). The influence of initial soil moisture, saturated hydraulics conductivity, Ks, bulk density and slope on rates of soil loss were also evaluated. The rainfall simulator produced rainfall intensities between 90 and 160 mm/hr with durations from 45 to 60 min per run. BS plot exhibited the highest Ks value among all plots but the percentage of initial soil moisture on this surface was low. BS plot recorded the highest runoff coefficient (C) and soil loss values of 73.6 ± 4 percent and 5.26 ± 3.2 t/ha respectively, while the lowest was from plot FG with 41.7 ± 5.7 percent and soil loss of 2.85 ± 2.1 t/ha. Meanwhile, the results suggested that the ground cover had the ability to reduce soil loss by 67% and 17%, respectively for plots BS-HGC and BS-HDF. Overall, soil erosion control such as surface is effective measures in reducing level of runoff and soil erosion.

  14. Measurement of soil moisture using gypsum blocks

    DEFF Research Database (Denmark)

    Friis Dela, B.

    the building. Consequently, measuring the moisture of the surrounding soil is of great importance for detecting the source of moisture in a building. Up till now, information has been needed to carry out individual calibrations for the different types of gypsum blocks available on the market and to account......For the past 50 years, gypsum blocks have been used to determine soil moisture content. This report describes a method for calibrating gypsum blocks for soil moisture measurements. Moisture conditions inside a building are strongly influenced by the moisture conditions in the soil surrounding...

  15. Measurement of soil moisture using gypsum blocks

    DEFF Research Database (Denmark)

    Friis Dela, B.

    For the past 50 years, gypsum blocks have been used to determine soil moisture content. This report describes a method for calibrating gypsum blocks for soil moisture measurements. Moisture conditions inside a building are strongly influenced by the moisture conditions in the soil surrounding...... the building. Consequently, measuring the moisture of the surrounding soil is of great importance for detecting the source of moisture in a building. Up till now, information has been needed to carry out individual calibrations for the different types of gypsum blocks available on the market and to account...

  16. Long-term effects of soil management on ecosystem services and soil loss estimation in olive grove top soils.

    Science.gov (United States)

    Parras-Alcántara, Luis; Lozano-García, Beatriz; Keesstra, Saskia; Cerdà, Artemi; Brevik, Eric C

    2016-11-15

    Soil management has important effects on soil properties, runoff, soil losses and soil quality. Traditional olive grove (OG) management is based on reduced tree density, canopy size shaped by pruning and weed control by ploughing. In addition, over the last several decades, herbicide use has been introduced into conventional OG management. These management strategies cause the soil surface to be almost bare and subsequently high erosion rates take place. To avoid these high erosion rates several soil management strategies can be applied. In this study, three strategies were assessed in OG with conventional tillage in three plots of 1ha each. Soil properties were measured and soil erosion rates were estimated by means of the RUSLE model. One plot was managed with no amendments (control), and the other two were treated with olive leaves mulch and oil mill pomace applied yearly from 2003 until 2013. The control plot experienced the greatest soil loss while the use of olive leaves as mulch and olive mill pomace as an amendment resulted in a soil loss reduction of 89.4% and 65.4% respectively (assuming a 5% slope). In addition, the chemical and physical soil properties were improved with the amendments. This combined effect will created a higher quality soil over the long term that it is more resilient to erosion and can provide better ecosystem services, as its functions are improved.

  17. Soil erosion dynamics response to landscape pattern.

    Science.gov (United States)

    Ouyang, Wei; Skidmore, Andrew K; Hao, Fanghua; Wang, Tiejun

    2010-02-15

    Simulating soil erosion variation with a temporal land use database reveals long-term fluctuations in landscape patterns, as well as priority needs for soil erosion conservation. The application of a multi-year land use database in support of a Soil Water Assessment Tool (SWAT) led to an accurate assessment, from 1977 to 2006, of erosion in the upper watershed of the Yellow River. At same time, the impacts of land use and landscape service features on soil erosion load were assessed. A series of supervised land use classifications of Landsat images characterized variations in land use and landscape patterns over three decades. The SWAT database was constructed with soil properties, climate and elevation data. Using water flow and sand density data as parameters, regional soil erosion load was simulated. A numerical statistical model was used to relate soil erosion to land use and landscape. The results indicated that decadal decrease of grassland areas did not pose a significant threat to soil erosion, while the continual increase of bare land, water area and farmland increased soil erosion. Regional landscape variation also had a strong relationship with erosion. Patch level landscape analyses demonstrated that larger water area led to more soil erosion. The patch correlation indicated that contagious grassland patches reduced soil erosion yield. The increased grassland patches led to more patch edges, in turn increasing the sediment transportation from the patch edges. The findings increase understanding of the temporal variation in soil erosion processes, which is the basis for preventing local pollution.

  18. Effects of Vegetation Removal and Soil Disturbance on Soil Organic and Inorganic Carbon Dynamics in California Desert Ecosystems

    Science.gov (United States)

    Swanson, A. C.; Allen, E. B.; Allen, M. F.; Hernandez, R. R.

    2015-12-01

    Solar energy developments are projected to be deployed over desert wildland areas with deep soil inorganic carbon (SIC) deposits, which often involves elimination of deep-rooted vegetation. This land cover change may systemically alter SIC pools since respired CO2 is the carbon (C) source during SIC formation. We sought to understand how removal of creosote bush scrub affects soil C pools. We hypothesized that vegetation is important for maintaining SIC and soil organic C (SOC) pools and that disturbance to the vegetation and soil will change CO2 flux with increased losses from SIC. Soils were collected from sites that had intact creosote bush scrub habitat adjacent to disturbed, bare areas where the native vegetation had been previously removed. Samples were taken from beneath shrub canopies and interspaces in intact areas, and from random points in the disturbed area. Soils were analyzed for SIC, SOC, microbial and labile C, and δ13C. Soils were also incubated to determine the potential CO2 flux from disturbed and undisturbed soils along with the sources of CO2. Three replicates per soil underwent a control and water addition treatment and flux and δ13C of CO2 were measured continuously. Control replicates yielded no significant CO2 flux. CO2 flux from watered soils was higher beneath shrub canopy (18.57µmol g soil-1 day-1±1.86) than the interspace soils (0.86 µmol g soil-1 day-1±0.17). Soils collected from bare areas had an intermediate flux (5.41 µmol g soil-1 day-1±2.68 and 3.68 µmol g soil-1 day-1±0.85, respectively) lying between shrub canopy and interspace soils. There was no significant difference between the δ13C values of CO2 from shrub canopy and interspace soils, both of which had a very low δ13C values (-22.60‰±0.64 and -23.88‰±0.89, respectively), resembling that of organic C. However, the isotopic values of CO2 from disturbed soils were significantly higher (-16.68‰±1.36 and -15.22‰±2.12, respectively) suggesting that these

  19. Soil carbon sequestration by three perennial legume pastures is greater in deeper soil layers than in the surface soil

    Directory of Open Access Journals (Sweden)

    X.-K. Guan

    2015-07-01

    Full Text Available Soil organic carbon (SOC plays a vital role as both a sink for and source of atmospheric carbon. Revegetation of degraded arable land in China is expected to increase soil carbon sequestration, but the role of perennial legumes on soil carbon stocks in semiarid areas has not been quantified. In this study, we assessed the effect of alfalfa (Medicago sativa L. and two locally adapted forage legumes, bush clover (Lespedeza davurica S. and milk vetch (Astragalus adsurgens Pall. on the SOC concentration and SOC stock accumulated annually over a 2 m soil profile, and to estimate the long-term potential for SOC sequestration in the soil under the three forage legumes. The results showed that the concentration of SOC of the bare soil decreased slightly over the 7 years, while 7 years of legume growth substantially increased the concentration of SOC over the 0–2.0 m soil depth measured. Over the 7 year growth period the SOC stocks increased by 24.1, 19.9 and 14.6 Mg C ha−1 under the alfalfa, bush clover and milk vetch stands, respectively, and decreased by 4.2 Mg C ha−1 under bare soil. The sequestration of SOC in the 1–2 m depth of soil accounted for 79, 68 and 74 % of SOC sequestered through the upper 2 m of soil under alfalfa, bush clover and milk vetch, respectively. Conversion of arable land to perennial legume pasture resulted in a significant increase in SOC, particularly at soil depths below 1 m.

  20. Atmospheric mercury emissions from mine wastes and surrounding geologically enriched terrains

    Science.gov (United States)

    Gustin, M.S.; Coolbaugh, M.F.; Engle, M.A.; Fitzgerald, B.C.; Keislar, R.E.; Lindberg, S.E.; Nacht, D.M.; Quashnick, J.; Rytuba, J.J.; Sladek, C.; Zhang, H.; Zehner, R.E.

    2003-01-01

    Waste rock and ore associated with Hg, precious and base metal mining, and their surrounding host rocks are typically enriched in mercury relative to natural background concentrations (soil:air interface, and photo reduction of mercury containing phases. To determine the need for and effectiveness of regulatory controls on short-lived anthropogenic point sources the contribution of mercury from geologic non-point sources to the atmospheric mercury pool needs to be quantified. The atmospheric mercury contribution from small areas of mining disturbance with relatively high mercury concentrations are, in general, less than that from surrounding large areas of low levels of mercury enrichment. In the arid to semi-arid west-ern United States volatilization is the primary means by which mercury is released from enriched sites.

  1. Winter soil respiration from different vegetation patches in the Yellow River Delta, China.

    Science.gov (United States)

    Han, Guangxuan; Yu, Junbao; Li, Huabing; Yang, Liqiong; Wang, Guangmei; Mao, Peili; Gao, Yongjun

    2012-07-01

    Vegetation type and density exhibited a considerable patchy distribution at very local scales in the Yellow River Delta, due to the spatial variation of soil salinity and water scarcity. We proposed that soil respiration is affected by the spatial variations in vegetation type and soil chemical properties and tested this hypothesis in three different vegetation patches (Phragmites australis, Suaeda heteroptera and bare soil) in winter (from November 2010 to April 2011). At diurnal scale, soil respiration all displayed single-peak curves and asymmetric patterns in the three vegetation patches; At seasonal scale, soil respiration all declined steadily until February, and then increased to a peak in next April. But, the magnitude of soil respiration showed significant differences among the three sites. Mean soil respiration rates in winter were 0.60, 0.45 and 0.17 μmol CO(2) m(-2) s(-1) for the Phragmites australis, Suaeda heteroptera and bare soil, respectively. The combined effect of soil temperature and soil moisture accounted for 58-68 % of the seasonal variation of winter soil respiration. The mean soil respiration revealed positive and linear correlations with total N, total N and SOC storages at 0-20 cm depth, and plant biomass among the three sites. We conclude that the patchy distribution of plant biomass and soil chemical properties (total C, total N and SOC) may affect decomposition rate of soil organic matter in winter, thereby leading to spatial variations in soil respiration.

  2. Sub-pixel estimation of tree cover and bare surface densities using regression tree analysis

    Directory of Open Access Journals (Sweden)

    Carlos Augusto Zangrando Toneli

    2011-09-01

    Full Text Available Sub-pixel analysis is capable of generating continuous fields, which represent the spatial variability of certain thematic classes. The aim of this work was to develop numerical models to represent the variability of tree cover and bare surfaces within the study area. This research was conducted in the riparian buffer within a watershed of the São Francisco River in the North of Minas Gerais, Brazil. IKONOS and Landsat TM imagery were used with the GUIDE algorithm to construct the models. The results were two index images derived with regression trees for the entire study area, one representing tree cover and the other representing bare surface. The use of non-parametric and non-linear regression tree models presented satisfactory results to characterize wetland, deciduous and savanna patterns of forest formation.

  3. Proposal to observe half-bare electrons on a 45-MeV linac

    Science.gov (United States)

    Trofymenko, S. V.; Shul'ga, N. F.; Delerue, N.; Jenzer, S.; Khodnevych, V.; Migayron, A.

    2017-07-01

    The experimental investigation of the transition radiation (TR) generated by a “half-bare” electron having the proper field different from the Coulomb one is proposed. The electrons in half-bare state are intended to be obtained in the result of their crossing of a conducting screen. We propose to investigate the influence of the half-bare state of electron in this process upon TR generated by such electron on a downstream OTR screen situated on some distance along the direction of the electron beam from the upstream screen which “undresses” the particle. Calculations are presented for the case of a 45 MeV linac and the distance between the screens in the region between 100 mm and 300 mm. The proposed experiment is expected to reveal new features of TR signal in such process comparing to previous measurements.

  4. Oceanic corrosion test of bare and zinc-protected aluminum alloys for seawater heat exchangers

    Energy Technology Data Exchange (ETDEWEB)

    Sasscer, D.S.; Ernst, R.; Morgan, T.O.; Rivera, C.; Scott, A.C.; Summerson, T.J.

    1984-01-01

    In a cooperative research effort between The Puerto Rico Center of Energy and Environment Research, Kaiser Aluminum and Chemical Corporation and The Trane Company, a six month study was made of the seawater corrosion performance of various aluminum materials to test their suitability for use in seawater heat exchangers. The materials tested included bare 3004 tubes, 7072 Alclad 3004 tubes and bare and zinc diffusion treated 3003 extrusions from a brazed aluminum, plate-fin heat exchanger extrusions from a brazed aluminium, plate-fin heat exchanger developed by The Trane Company. The test materials were exposed to 1.8 m/sec flowing seawater aboard an open ocean test facility moored 3.4 km off the southeast coast of Puerto Rico. After six months exposure, the average corrosion rates for most varieties of aluminum materials converged to a low value of 0.015 mm/yr (0.6 mils/yr).

  5. Effects of lidar point density on bare earth extraction and DEM creation

    Science.gov (United States)

    Puetz, Angela M.; Olsen, R. Chris; Anderson, Brian

    2009-05-01

    Data density has a crucial impact on the accuracy of Digital Elevation Models (DEMs). In this study, DEMs were created from a high point-density LIDAR dataset using the bare earth extraction module in Quick Terrain Modeler. Lower point-density LIDAR collects were simulated by randomly selecting points from the original dataset at a series of decreasing percentages. The DEMs created from the lower resolution datasets are compared to the original DEM. Results show a decrease in DEM accuracy as the resolution of the LIDAR dataset is reduced. Some analysis is made of the types of errors encountered in the lower resolution DEMs. It is also noted that the percentage of points classified as bare earth decreases as the resolution of the LIDAR dataset is reduced.

  6. Long-term continuous atmospheric CO2 measurements at Baring Head, New Zealand

    Directory of Open Access Journals (Sweden)

    S. E. Nichol

    2012-12-01

    Full Text Available We present descriptions of the in situ instrumentation, calibration procedures, intercomparison efforts, and data filtering methods used in a 39-yr record of continuous atmospheric carbon dioxide (CO2 observations made at Baring Head, New Zealand. Located on the southern coast of the North Island, Baring Head is exposed to extended periods of strong air flow from the south with minimal terrestrial influence resulting in low CO2 variability. The site is therefore well suited for sampling air masses that are representative of the Southern Ocean region. Instrumental precision is better than 0.015 ppm (1-σ on 1-Hz values. Comparisons to over 600 co-located flask samples, as well as laboratory based flask and cylinder comparison exercises, suggest that over recent decades compatibility with respect to the Scripps Institution of Oceanography (SIO and World Meteorological Organisation (WMO CO2 scales has been 0.3 ppm or better.

  7. Linking plants, fungi and soil mechanics

    Science.gov (United States)

    Yildiz, Anil; Graf, Frank

    2017-04-01

    Plants provide important functions in respect soil strength and are increasingly considered for slope stabilisation within eco-engineering methods, particularly to prevent superficial soil failure. The protective functions include hydrological regulation through interception and evapo-transpiration as well as mechanical stabilisation through root reinforcement and, to a certain extent, chemical stabilisation through sticky metabolites. The ever-growing application of plants in slope stabilisation demanded more precise information of the vegetation effects and, concomitant, led the models for quantifying the reinforcement shoot up like mushrooms. However, so far, the framework and interrelationships for both the role of plants and the quantification concepts have not been thoroughly analysed and comprehensively considered, respectively, often resulting in unsatisfactory results. Although it seems obvious and is implicitly presupposed that the plant specific functions related to slope stability require growth and development, this is anything but given, particularly under the often hostile conditions dominating on bare and steep slopes. There, the superficial soil layer is often characterised by a lack of fines and missing medium-sized and fine pores due to an unstable soil matrix, predominantly formed by coarse grains. Low water retention capacity and substantial leaching of nutrients are the adverse consequences. Given this general set-up, sustainable plant growth and, particularly, root development is virtually unachievable. At exactly this point mycorrhizal fungi, the symbiotic partners of almost all plants used in eco-engineering, come into play. Though, they are probably well-known within the eco-engineering community, mycorrhizal fungi lead a humble existence. This is in spite of the fact that they supply their hosts with water and nutrients, improving the plant's ability to master otherwise unbridgeable environmental conditions. However, in order to support

  8. Transportable Waste-to-Energy System (TWES) Energy Recovery From Bare Base Waste

    Science.gov (United States)

    2008-02-01

    removed and/or partially burned. Instead the furnace, coupled with a shredder , will completely burn the waste and provide heat for water or other...Photos from Ali Al Salem, AF bare base Nov 1998, FOUO-for official use only 8 8 TWES Fuel Processing Bulk Trash Shredder Shredded Fuel TWES Furnace...Program (FEMP) to initiate the conversion. • Will install and test electricity production at Tyndall AFB 15 15 TWES Process Diagram Shredders Useful

  9. Optical coupling of bare optoelectronic components and flexographically printed polymer waveguides in planar optronic systems

    Science.gov (United States)

    Wang, Yixiao; Wolfer, Tim; Lange, Alex; Overmeyer, Ludger

    2016-05-01

    Large scale, planar optronic systems allowing spatially distributed functionalities can be well used in diverse sensor networks, such as for monitoring the environment by measuring various physical quantities in medicine or aeronautics. In these systems, mechanically flexible and optically transparent polymeric foils, e.g. polymethyl methacrylate (PMMA) and polyethylene terephthalate (PET), are employed as carrier materials. A benefit of using these materials is their low cost. The optical interconnections from light sources to light transmission structures in planar optronic systems occupy a pivotal position for the sensing functions. As light sources, we employ the optoelectronic components, such as edgeemitting laser diodes, in form of bare chips, since their extremely small structures facilitate a high integration compactness and ensure sufficient system flexibility. Flexographically printed polymer optical waveguides are deployed as light guiding structures for short-distance communication in planar optronic systems. Printing processes are utilized for this generation of waveguides to achieve a cost-efficient large scale and high-throughput production. In order to attain a high-functional optronic system for sensing applications, one of the most essential prerequisites is the high coupling efficiency between the light sources and the waveguides. Therefore, in this work, we focus on the multimode polymer waveguide with a parabolic cross-section and investigate its optical coupling with the bare laser diode. We establish the geometrical model of the alignment based on the previous works on the optodic bonding of bare laser diodes and the fabrication process of polymer waveguides with consideration of various parameters, such as the beam profile of the laser diode, the employed polymer properties of the waveguides as well as the carrier substrates etc. Accordingly, the optical coupling of the bare laser diodes and the polymer waveguides was simulated

  10. Bare-State Time-Evolving Operator Solution to Raman Model in A Configuration

    Institute of Scientific and Technical Information of China (English)

    WUYing; NIEYi-Zhen; YANGXiao-Xue

    2003-01-01

    We derive exact analytical expressions of time-evolving bare-state operators of level occupation numbers and the photon numbers for a composite system consisting of a three-level atom interacting with two modes ofa quantized electromagnetic field in A configuration. These results demonstrate the oscillations with three-family frequencies for a nonzero detuning, which dramatically differ from the previous results showing only single-family Rabi oscillations.

  11. Bare-State Time-Evolving Operator Solution to Raman Model in A Configuration

    Institute of Scientific and Technical Information of China (English)

    WU Ying; NIE Yi-Zhen; YANG Xiao-Xue

    2003-01-01

    We derive exact analytical expressions of time-evolving bare-state operators of level occupation numbers and the photon numbers for a composite system consisting of a three-level atom interacting with two modes of a quantized electromagnetic field in A configuration. These results demonstrate the oscillations with three-family frequencies for a nonzero detuning, which dramatically differ from the previous results showing only single-family Rabi oscillations.

  12. Maps of averaged spectral deviations from soil lines and their comparison with traditional soil maps

    Science.gov (United States)

    Rukhovich, D. I.; Rukhovich, A. D.; Rukhovich, D. D.; Simakova, M. S.; Kulyanitsa, A. L.; Bryzzhev, A. V.; Koroleva, P. V.

    2016-07-01

    The analysis of 34 cloudless fragments of Landsat 5, 7, and 8 images (1985-2014) on the territory of Plavsk, Arsen'evsk, and Chern districts of Tula oblast has been performed. It is shown that bare soil surface on the RED-NIR plots derived from the images cannot be described in the form of a sector of spectral plane as it can be done for the NDVI values. The notion of spectral neighborhood of soil line (SNSL) is suggested. It is defined as the sum of points of the RED-NIR spectral space, which are characterized by spectral characteristics of the bare soil applied for constructing soil lines. The way of the SNSL separation along the line of the lowest concentration density of points on the RED-NIR spectral space is suggested. This line separates bare soil surface from vegetating plants. The SNSL has been applied to construct soil line (SL) for each of the 34 images and to delineate bare soil surface on them. Distances from the points with averaged RED-NIR coordinates to the SL have been calculated using the method of moving window. These distances can be referred to as averaged spectral deviations (ASDs). The calculations have been performed strictly for the SNSL areas. As a result, 34 maps of ASDs have been created. These maps contain ASD values for 6036 points of a grid used in the study. Then, the integral map of normalized ASD values has been built with due account for the number of points participating in the calculation (i.e., lying in the SNSL) within the moving window. The integral map of ASD values has been compared with four traditional soil maps on the studied territory. It is shown that this integral map can be interpreted in terms of soil taxa: the areas of seven soil subtypes (soddy moderately podzolic, soddy slightly podzolic, light gray forest. gray forest, dark gray forest, podzolized chernozems, and leached chernozems) belonging to three soil types (soddy-podzolic, gray forest, and chernozemic soils) can be delineated on it.

  13. Bare below elbows: does this policy affect handwashing efficacy and reduce bacterial colonisation?

    Science.gov (United States)

    Burger, A; Wijewardena, C; Clayson, S; Greatorex, R A

    2011-01-01

    UK Department of Health guidelines recommend that clinical staff are 'bare below the elbows'. There is a paucity of evidence to support this policy. One may hypothesise that absence of clothing around wrists facilitates more effective handwashing: this study aims to establish whether dress code affects bacterial colonisation before and after handwashing. Sixty-six clinical staff volunteered to take part in the study, noting whether they were bare below the elbows (BBE) or not bare (NB). Using a standardised technique, imprints of left and right fingers, palms, wrists and forearms were taken onto mini agar plates. Imprints were repeated after handwashing. After incubation, colonies per plate were counted, and subcultures taken. Thirty-eight staff were BBE and 28 were not. A total of 1112 plates were cultured. Before handwashing there was no significant difference in number of colonies between BBE and NB groups (Mann-Whitney, P < 0.05). Handwashing reduced the colony count, with greatest effect on fingers, palms and dominant wrists (t-test, P < 0.05). Comparing the two groups again after handwashing revealed no significant difference (Mann-Whitney, P < 0.05). Subcultures revealed predominantly skin flora. There was a large variation in number of colonies cultured. Handwashing resulted in a statistically significant reduction in colony count on fingers, palms and dominant wrist regardless of clothing. We conclude that handwashing produces a significant reduction in number of bacterial colonies on staff hands, and that clothing that is not BBE does not impede this reduction.

  14. Percutaneous Creation of Bare Intervascular Tunnels for Salvage of Thrombosed Hemodialysis Fistulas Without Recanalizable Outflow

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Matt Chiung-Yu, E-mail: jjychen@gmail.com [Yuan’s General Hospital, Department of Interventional Radiology (China); Wang, Yen-Chi [E-Da Hospital, Department of Radiology (China); Weng, Mei-Jui [Kaohsiung Veterans General Hospital, Department of Radiology (China)

    2015-08-15

    PurposeThis study aimed to retrospectively assess the efficacy of a bare intervascular tunnel for salvage of a thrombosed hemodialysis fistula. We examined the clinical outcomes and provided follow-up images of the bare intervascular tunnel.Materials and MethodsEight thrombosed fistulas lacked available recanalizable outflow veins were included in this study. These fistulas were salvaged by re-directing access site flow to a new outflow vein through a percutaneously created intervascular tunnel without stent graft placement. The post-intervention primary and secondary access patency rates were calculated using the Kaplan–Meier method.ResultsThe procedural and clinical success rates were 100 %. Post-intervention primary and secondary access patency at 300 days were 18.7 ± 15.8 and 87.5 ± 11.7 %, respectively. The mean follow-up period was 218.7 days (range 10–368 days). One patient died of acute myocardial infarction 10 days after the procedure. No other major complications were observed. Minor complications, such as swelling, ecchymosis, and pain around the tunnel, occurred in all of the patients.ConclusionsPercutaneous creation of a bare intervascular tunnel is a treatment option for thrombosed hemodialysis fistulas without recanalizable outflow in selected patients.

  15. Clinical utility of platinum chromium bare-metal stents in coronary heart disease

    Directory of Open Access Journals (Sweden)

    Jorge C

    2015-08-01

    Full Text Available Claudia Jorge,1 Christophe Dubois1,2 1Department of Cardiovascular Medicine, University Hospitals Leuven, 2Department of Cardiovascular Sciences, Katholieke Universiteit Leuven, Leuven, Belgium Abstract: Coronary stents represent a key development for the treatment of obstructive coronary artery disease since the introduction of percutaneous coronary intervention. While drug-eluting stents gained wide acceptance in contemporary percutaneous coronary intervention practice, further developments in bare-metal stents remain crucial for patients who are not candidates for drug-eluting stents, or to improve metallic platforms for drug elution. Initially, stent platforms used biologically inert stainless steel, restricting stent performance due to limitations in flexibility and strut thickness. Later, cobalt chromium stent alloys outperformed steel as the material of choice for stents, allowing latest generation stents to be designed with significantly thinner struts, while maintaining corrosion resistance and radial strength. Most recently, the introduction of the platinum chromium alloy refined stent architecture with thin struts, high radial strength, conformability, and improved radiopacity. This review will provide an overview of the novel platinum chromium bare-metal stent platforms available for coronary intervention. Mechanical properties, clinical utility, and device limitations will be summarized and put into perspective. Keywords: bare metal stent, coronary stent alloys, coronary artery disease

  16. Charge-exchange cross sections and beam lifetimes for stored and decelerated bare uranium ions

    Energy Technology Data Exchange (ETDEWEB)

    Stoehlker, T. [Frankfurt Univ. (Germany). Inst. fuer Kernphysik]|[Gesellschaft fuer Schwerionenforschung mbH, Darmstadt (Germany); Ludziejewski, T.; Reich, H.; Bosch, F.; Franzke, B.; Kozhuharov, C.; Menzel, G.; Mokler, P.H.; Nolden, F.; Steck, M. [Frankfurt Univ. (Germany). Inst. fuer Kernphysik; Dunford, R.W. [Argonne National Lab., IL (United States). Physics Div.; Eichler, J. [Hahn-Meitner-Institut Berlin GmbH (Germany). Bereich Theoretische Physik]|[Freie Univ. Berlin (Germany). Fachbereich Physik; Rymuza, P. [Soltan Inst. for Nuclear Studies, Otwock-Swierk (Poland); Stachura, Z. [Institute of Nuclear Physics, Cracow (Poland); Swiat, P.; Warczak, A. [Uniwersytet Jagiellonski, Cracow (Poland). Inst. Fizyki; Winkler, T. [Gesellschaft fuer Schwerionenforschung mbH, Darmstadt (Germany)

    1998-08-01

    Charge-exchange cross sections and beam lifetimes are studied for decelerated bare uranium ions at the ESR storage ring. By deceleration from the initial energy of 358 MeV/u down to various energies as low as 49 MeV/u, i.e. far below the production energy of bare ionic species, the electron pick-up cross sections were obtained for collisions with N{sub 2}, Ar, CH{sub 4} and Kr gaseous targets. The measured cross sections and beam lifetimes are compared with the theoretical results for radiative and non-radiative electron capture. The present data along with the theoretical approximations discussed, provide a solid basis for the estimation of beam lifetimes for decelerated bare high-Z ions. Moreover, a normalization procedure is proposed, in which absolute total charge-exchange cross sections are derived by normalizing the simultaneously measured yield of K-REC photons to rigorously calculated relativistic cross sections. This method along with the unprecedented beam conditions at the ESR storage ring, allows a significant improvement in the accuracy of cross section data. (orig.)

  17. Patches of bare ground as a staple commodity for declining ground-foraging insectivorous farmland birds.

    Directory of Open Access Journals (Sweden)

    Michael Schaub

    Full Text Available Conceived to combat widescale biodiversity erosion in farmland, agri-environment schemes have largely failed to deliver their promises despite massive financial support. While several common species have shown to react positively to existing measures, rare species have continued to decline in most European countries. Of particular concern is the status of insectivorous farmland birds that forage on the ground. We modelled the foraging habitat preferences of four declining insectivorous bird species (hoopoe, wryneck, woodlark, common redstart inhabiting fruit tree plantations, orchards and vineyards. All species preferred foraging in habitat mosaics consisting of patches of grass and bare ground, with an optimal, species-specific bare ground coverage of 30-70% at the foraging patch scale. In the study areas, birds thrived in intensively cultivated farmland where such ground vegetation mosaics existed. Not promoted by conventional agri-environment schemes until now, patches of bare ground should be implemented throughout grassland in order to prevent further decline of insectivorous farmland birds.

  18. Bare Shear Viscosity and Anomalous Fall Rate of Oil Droplets in Nitrogen

    Science.gov (United States)

    Varley, Rodney

    2011-11-01

    Experimental evidence of Kim and Fedele (1982) indicates a breakdown of the Millikan Law for the fall rate of oil droplets in Nitrogen gas over a pressure range of 1-15 atm. The discrepancy is most pronounced for smallest, 0.1 micron radius droplets for which the fall rate increases with pressure. The opposite behavior was observed by Millikan with larger drops in air of pressure at most one atm. We explain these results by arguing that the particle's motion, in particular Stokes' drag formula, is determined by the so-called bare shear viscosity which applies to micro fluid flows. This is in contrast with the usual theory which uses a renormalized shear viscosity and which is well approximated by the Enskog value. A mode coupling formula for the bare shear viscosity is discussed and a graphical comparison is made with the experimental results. Basically an increase in gas pressure produces a decrease in the bare shear viscosity and thus the fall rate increases. The idea that the shear viscosity is smaller for micro flows is consistent with the intuitive belief that on small enough spatial and time scales, fluid flows are conservative without dissipation.

  19. Estimating soil moisture using the Danish polarimetric SAR

    DEFF Research Database (Denmark)

    Jiankang, Ji; Thomsen, A.; Skriver, Henning

    1995-01-01

    The results of applying data from the Danish polarimetric SAR (EMISAR) to estimate soil moisture for bare fields are presented. Fully calibrated C-band SAR images for hh, vv and cross polarizations have been used in this study. The measured surface roughness data showed that classical roughness...... autocorrelation functions (Gaussian and Exponential) were not able to fit natural surfaces well. A Gauss-Exp hybrid model which agreed better with the measured data has been proposed. Theoretical surface scattering models (POM, IEM), as well as an empirical model for retrieval of soil moisture and surface rms...... height from coand cross-polarized ratio, have been examined, but the results are less satisfactory. As soil moisture response to backscattering coefficient σo is mainly coupled to surface roughness effect for bare fields, a bilinear model coupling volumetric soil moisture mv and surface rms height σ...

  20. THE CLASSIFICATION OF THE SURROUNDINGS OF COAL MINING ROADWAYS

    Institute of Scientific and Technical Information of China (English)

    邹喜正; 侯朝炯; 李华祥

    1996-01-01

    This introduces the calculation of opaper the deformationg .the Surroundings of coaowaysand the divisi of surroundings into 5 levels by means or !fuzzy integral assess mairrx, wnlcnserves-asthe scientific basis for selecting supporting pattern of roadways and determining the, pa-rameters of support.

  1. Soil-Pile Interaction in the Pile Vertical Vibration Based on Fictitious Soil-Pile Model

    OpenAIRE

    Guodong Deng; Jiasheng Zhang; Wenbing Wu; Xiong Shi; Fei Meng

    2014-01-01

    By introducing the fictitious soil-pile model, the soil-pile interaction in the pile vertical vibration is investigated. Firstly, assuming the surrounding soil of pile to be viscoelastic material and considering its vertical wave effect, the governing equations of soil-pile system subjected to arbitrary harmonic dynamic force are founded based on the Euler-Bernoulli rod theory. Secondly, the analytical solution of velocity response in frequency domain and its corresponding semianalytical solu...

  2. Physical geography of the Nete basin and surroundings; Fysische geografie van het Netebekken en omgeving

    Energy Technology Data Exchange (ETDEWEB)

    Beerten, K.

    2011-05-15

    The report briefly describes the main features of the physical geography of the Nete basin (Campine region, Belgium) and its immediate surroundings. First, an integrated overview of the topography, morphology and hydrography is given. This overview serves as the basis for the assessment of the morphological stability of the region and also explains the relationship between the topography and the hydrology. Furthermore, special attention is paid to soil science including a quantitative survey of some soil characteristics data. Another part of this report deals with erosion processes caused by water and wind action, and the (potential) impact on the morphology. Finally, the palaeogeographical evolution during the Quaternary is discussed. This evolution shows that the environment is stable over 10 000 years or more in the current and similar climatic conditions. Altering climatic conditions, notably glacial-interglacial periods, have impacted erosion with periods of strong erosion.

  3. Metal biomonitoring with mosses in the surroundings of an oil-fired power plant in Italy

    Energy Technology Data Exchange (ETDEWEB)

    Genoni, P.; Parco, V. [Presidio Multizonale di Igiene e Prevenzione, Parabiago, MI (Italy); Santagostino, A. [Unversita degli Studi di Milano-Bicocca, Milan (Italy). Dip. di Scienze dell' Ambiente e del Territorio

    2000-09-01

    Levels of 12 trace elements were measured in samples of the bryophyte Hypnum cupressiforme Hedw. and in soil collected in the surroundings of an oil-fired power plant in Northern Italy. Metal bioaccumulation in moss was estimated after soil correction in order to obtain deposition patterns and individuate potentially toxic metals emitted from the plant. V and Ni, occurring together in fuel oil, showed highest bioaccumulation values near the stacks. Mean contamination of the study area for these elements is 5.5 (V) and 3.3 (Ni) times the background levels of the reference site. Other elements showed only limited alterations of bioaccumulation values, in relation to agricultural and industrial activity in the study area. (Author)

  4. The effects of different soil cover management practices on plant biodiversity and soil properties in Mediterranean ancient olive orchards

    Science.gov (United States)

    Madzaric, Suzana; Aly, Adel; Ladisa, Gaetano; Calabrese, Generosa

    2014-05-01

    The effects of different soil cover management practices on plant biodiversity and soil properties in Mediterranean ancient olive orchards Madzaric S., Aly A., Ladisa G. and Calabrese G. The loss of natural plant cover due to the inappropriate soil cover management is often a decisive factor for soil degradation in Mediterranean area. This accompanied with typical climate, characterized by cool, wet winters and hot and dry summers leads to soil erosion and loss of productivity. Due to simplification of agricultural practice and to the attempt to decrease cost of production, keeping soil bare is a widespread agricultural practice in Mediterranean ancient olive orchards (AOOs). The consequences of this are degradation of soil quality and reduction of plant biodiversity. In last year's some alternative practices are proposed in order to protect soil and biodiversity. One of these practices is the "grassing" i.e. covering the soil by selected autochthonous plant species. Objectives of our study are: (1) to evaluate impact of different soil cover management practices on soil properties and plant biodiversity in AOOs and (2) to define a minimum indicators' set (Minimum Data Set - MDS) to evaluate the effectiveness of different agricultural practices in environmental performance of AOOs. A comparison was carried on considering two management systems (conventional vs. organic) and three agricultural practices: conventional with bare soil (CON), organic with soil covered by selected autochthonous species (MIX) and organic left to the native vegetation (NAT). In general a clear positive influence of organic management system was recognized. Some soil quality indicators (physical, chemical and biological) showed responsiveness in describing the effects of management system and agricultural practices on soil properties. The both approaches with vegetation cover on the soil surface (either sowing of mixture or soil left to the natural plant cover) performed better than

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

    Directory of Open Access Journals (Sweden)

    Linares Rubén

    2014-01-01

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

  6. Plant-mediated effects on extracellular enzyme activities in distinct soil aggregate size classes in field

    Science.gov (United States)

    Kumar, Amit; Dorodnikov, Maxim; Splettstößer, Thomas; Kuzyakov, Yakov; Pausch, Johanna

    2017-04-01

    Soil aggregation and microbial activities within the aggregates are important factors regulating soil carbon (C) turnover. A reliable and sensitive proxy for microbial activity is activity of extracellular enzymes (EEA). In the present study, effects of soil aggregates on EEA were investigated under three maize plant densities (Low, Normal, and High). Bulk soil was fractionated into three aggregate size classes (>2000 µm large macroaggregates; 2000-250 µm small macroaggregates; moisture sieving. Microbial biomass and EEA (β-1,4-glucosidase (BG), β-1,4-N-acetylglucosaminidase (NAG), L-leucine aminopeptidase (LAP) and acid phosphatase (acP)) catalyzing soil organic matter (SOM) decomposition were measured in rooted soil of maize and soil from bare fallow. Microbial biomass C (Cmic) decreased with decreasing aggregate size classes. Potential and specific EEA (per unit of Cmic) increased from macro- to microaggregates. In comparison with bare fallow soil, specific EEA of microaggregates in rooted soil was higher by up to 73%, 31%, 26%, and 92% for BG, NAG, acP and LAP, respectively. Moreover, high plant density decreased macroaggregates by 9% compared to bare fallow. Enhanced EEA in three aggregate size classes demonstrated activation of microorganisms by roots. Strong EEA in microaggregates can be explained by microaggregates' localization within the soil. Originally adhering to surfaces of macroaggregates, microaggregates were preferentially exposed to C substrates and nutrients, thereby promoting microbial activity.

  7. Iodine in soil

    Energy Technology Data Exchange (ETDEWEB)

    Johanson, Karl Johan [Swedish Univ. of Agricultural Sciences, Uppsala (Sweden). Dept. of Forest Mycology and Pathology

    2000-12-01

    A literature study of the migration and the appearance of iodine isotopes in the bio-sphere particularly in soil is presented. Some important papers in the field of iodine appearance in soil and the appearance of {sup 129}I in the surroundings of reprocessing plants are discussed. The most important conclusions are: 1. Iodine binds to organic matter in the soil and also to some oxides of aluminium and iron. 2. If the iodine is not bound to the soil a large fraction of added {sup 129}I is volatilized after a rather short period. 3. The binding and also the volatilisation seems to be due to biological activity in the soil. It may take place within living microorganisms or by external enzymes excreted from microorganisms. 4. Due to variations in the composition of soil there may be a large variation in the distribution of {sup 129}I in the vertical profile of soil - usually most of the {sup 129}I in the upper layer - which also results in large variations in the {sup 129}I uptake to plants.

  8. Black hole solutions surrounded by perfect fluid in Rastall theory

    Science.gov (United States)

    Heydarzade, Y.; Darabi, F.

    2017-08-01

    In this work, we obtain uncharged∖charged Kiselev-like black holes as a new class of black hole solutions surrounded by perfect fluid in the context of Rastall theory. Then, we study the specific cases of the uncharged∖charged black holes surrounded by regular matter like dust and radiation, or exotic matter like quintessence, cosmological constant and phantom fields. By comparing the Kiselev-like black hole solutions in Rastall theory with the Kiselev black hole solutions in GR, we find an effective perfect fluid behavior for the black hole's surrounding field. It is shown that the corresponding effective perfect fluid has interesting characteristic features depending on the different ranges of the parameters in Rastall theory. For instance, Kiselev-like black holes surrounded by regular matter in Rastall theory may be considered as Kiselev black holes surrounded by exotic matter in GR, or Kiselev-like black holes surrounded by exotic matter in Rastall theory may be considered as Kiselev black holes surrounded by regular matter in GR.

  9. Surround suppression and sparse coding in visual and barrel cortices

    Directory of Open Access Journals (Sweden)

    Robert N S Sachdev

    2012-07-01

    Full Text Available During natural vision the entire retina is stimulated. Likewise, during natural tactile behaviors, spatially extensive regions of the somatosensory surface are co-activated. The large spatial extent of naturalistic stimulation means that surround suppression, a phenomenon whose neural mechanisms remain a matter of debate, must arise during natural behavior. To identify common neural motifs that might instantiate surround suppression across modalities, we review models of surround suppression and compare the evidence supporting the competing ideas that surround suppression has either cortical or sub-cortical origins in visual and barrel cortex. In the visual system there is general agreement lateral inhibitory mechanisms contribute to surround suppression, but little direct experimental evidence that intracortical inhibition plays a major role. Two intracellular recording studies of V1, one using naturalistic stimuli (Haider et al., 2010, the other sinusoidal gratings (Ozeki et al., 2009, sought to identify the causes of reduced activity in V1 with increasing stimulus size, a hallmark of surround suppression. The former attributed this effect to increased inhibition, the latter to largely balanced withdrawal of excitation and inhibition. In rodent primary somatosensory barrel cortex, multi-whisker responses are generally weaker than single whisker responses, suggesting multi-whisker stimulation engages similar surround suppressive mechanisms. The origins of suppression in S1 remain elusive: studies have implicated brainstem lateral/internuclear interactions and both thalamic and cortical inhibition. Although the anatomical organization and instantiation of surround suppression in the visual and somatosensory systems differ, we consider the idea that one common function of surround suppression, in both modalities, is to remove the statistical redundancies associated with natural stimuli by increasing the sparseness or selectivity of sensory

  10. Drug-eluting stents versus bare-metal stents for acute coronary syndrome.

    Science.gov (United States)

    Feinberg, Joshua; Nielsen, Emil Eik; Greenhalgh, Janette; Hounsome, Juliet; Sethi, Naqash J; Safi, Sanam; Gluud, Christian; Jakobsen, Janus C

    2017-08-23

    Approximately 3.7 million people died from acute coronary syndrome worldwide in 2012. Acute coronary syndrome, also known as myocardial infarction or unstable angina pectoris, is caused by a sudden blockage of the blood supplied to the heart muscle. Percutaneous coronary intervention is often used for acute coronary syndrome, but previous systematic reviews on the effects of drug-eluting stents compared with bare-metal stents have shown conflicting results with regard to myocardial infarction; have not fully taken account of the risk of random and systematic errors; and have not included all relevant randomised clinical trials. To assess the benefits and harms of drug-eluting stents versus bare-metal stents in people with acute coronary syndrome. We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, LILACS, SCI-EXPANDED, and BIOSIS from their inception to January 2017. We also searched two clinical trials registers, the European Medicines Agency and the US Food and Drug Administration databases, and pharmaceutical company websites. In addition, we searched the reference lists of review articles and relevant trials. Randomised clinical trials assessing the effects of drug-eluting stents versus bare-metal stents for acute coronary syndrome. We included trials irrespective of publication type, status, date, or language. We followed our published protocol and the methodological recommendations of Cochrane. Two review authors independently extracted data. We assessed the risks of systematic error by bias domains. We conducted Trial Sequential Analyses to control the risks of random errors. Our primary outcomes were all-cause mortality, major cardiovascular events, serious adverse events, and quality of life. Our secondary outcomes were angina, cardiovascular mortality, and myocardial infarction. Our primary assessment time point was at maximum follow-up. We assessed the quality of the evidence by the GRADE approach. We included 25

  11. Influence of disturbance on soil respiration in biologically crusted soil during the dry season.

    Science.gov (United States)

    Feng, Wei; Zhang, Yu-qing; Wu, Bin; Zha, Tian-shan; Jia, Xin; Qin, Shu-gao; Shao, Chen-xi; Liu, Jia-bin; Lai, Zong-rui; Fa, Ke-yu

    2013-01-01

    Soil respiration (Rs) is a major pathway for carbon cycling and is a complex process involving abiotic and biotic factors. Biological soil crusts (BSCs) are a key biotic component of desert ecosystems worldwide. In desert ecosystems, soils are protected from surface disturbance by BSCs, but it is unknown whether Rs is affected by disturbance of this crust layer. We measured Rs in three types of disturbed and undisturbed crusted soils (algae, lichen, and moss), as well as bare land from April to August, 2010, in Mu Us desert, northwest China. Rs was similar among undisturbed soils but increased significantly in disturbed moss and algae crusted soils. The variation of Rs in undisturbed and disturbed soil was related to soil bulk density. Disturbance also led to changes in soil organic carbon and fine particles contents, including declines of 60-70% in surface soil C and N, relative to predisturbance values. Once BSCs were disturbed, Q 10 increased. Our findings indicate that a loss of BSCs cover will lead to greater soil C loss through respiration. Given these results, understanding the disturbance sensitivity impact on Rs could be helpful to modify soil management practices which promote carbon sequestration.

  12. Thermal Conductivity Prediction of Soil in Complex Plant Soil System using Artificial Neural Networks

    Science.gov (United States)

    Wardani, A. K.; Purqon, A.

    2016-08-01

    Thermal conductivity is one of thermal properties of soil in seed germination and plants growth. Different soil types have different thermal conductivity. One of soft-computing promising method to predict thermal conductivity of soil types is Artificial Neural Network (ANN). In this study, we estimate the thermal conductivity of soil prediction in a soil-plant complex systems using ANN. With a feed-forward multilayer trained with back-propagation with 4, 10 and 1 on the input, hidden and output layers respectively. Our input are heating time, temperature and thermal resistance with thermal conductivity of soil as a target. ANN prediction demonstrates a good agreement with Mean Squared Error-testing (MSEte) of 9.56 x 10-7 for soils with green beans and those of bare soils is 7.00 × 10-7 respectively Green beans grow only on black-clay soil with a thermal conductivity of 0.7 W/m K with a sufficient water content. Our results demonstrate that temperature, moisture content, colour, texture and structure of soil are greatly affect to the thermal conductivity of soil in seed germination and plant growth. In future, it is potentially applied to estimate more complex compositions of plant-soil systems.

  13. Influence of Disturbance on Soil Respiration in Biologically Crusted Soil during the Dry Season

    Directory of Open Access Journals (Sweden)

    Wei Feng

    2013-01-01

    Full Text Available Soil respiration (Rs is a major pathway for carbon cycling and is a complex process involving abiotic and biotic factors. Biological soil crusts (BSCs are a key biotic component of desert ecosystems worldwide. In desert ecosystems, soils are protected from surface disturbance by BSCs, but it is unknown whether Rs is affected by disturbance of this crust layer. We measured Rs in three types of disturbed and undisturbed crusted soils (algae, lichen, and moss, as well as bare land from April to August, 2010, in Mu Us desert, northwest China. Rs was similar among undisturbed soils but increased significantly in disturbed moss and algae crusted soils. The variation of Rs in undisturbed and disturbed soil was related to soil bulk density. Disturbance also led to changes in soil organic carbon and fine particles contents, including declines of 60–70% in surface soil C and N, relative to predisturbance values. Once BSCs were disturbed, Q10 increased. Our findings indicate that a loss of BSCs cover will lead to greater soil C loss through respiration. Given these results, understanding the disturbance sensitivity impact on Rs could be helpful to modify soil management practices which promote carbon sequestration.

  14. Semiquantitative color profiling of soils over a land degradation gradient in Sakaerat, Thailand.

    Science.gov (United States)

    Doi, Ryoichi; Wachrinrat, Chongrak; Teejuntuk, Sakhan; Sakurai, Katsutoshi; Sahunalu, Pongsak

    2010-11-01

    In this study, we attempted multivariate color profiling of soils over a land degradation gradient represented by dry evergreen forest (original vegetation), dry deciduous forest (moderately disturbed by fire), and bare ground (severely degraded) in Sakaerat, Thailand. The soils were sampled in a dry-to-wet seasonal transition. Values of the red-green-blue (RGB), cyan-magenta-yellow-key black (CMYK), L*a*b*, and hue-intensity-saturation (HIS) color models were determined using the digital software Adobe Photoshop. Land degradation produced significant variations (pland degradation gradient, due to effects of fire that darkened the deciduous forest soil, masking the nature of the soil as the intermediate between the evergreen forest and the bare ground soils. Taking these findings into account, the utilization of color profiling of soils in land conservation and rehabilitation is discussed.

  15. EAARL-B coastal topography: Fire Island, New York, pre-Hurricane Sandy, 2012: seamless (bare earth and submerged)

    Science.gov (United States)

    Wright, C. Wayne; Kranenburg, Christine J.; Klipp, Emily S.; Troche, Rodolfo J.; Fredericks, Alexandra M.; Masessa, Melanie L.; Nagle, David B.

    2014-01-01

    These remotely sensed, geographically referenced elevation measurements of lidar-derived seamless (bare-earth and submerged) topography datasets were produced by the U.S. Geological Survey (USGS), St. Petersburg Coastal and Marine Science Center, St. Petersburg, Florida.

  16. Benthic metabolism and denitrification in a river reach: a comparison between vegetated and bare sediments

    Directory of Open Access Journals (Sweden)

    Pierluigi VIAROLI

    2009-02-01

    Full Text Available This study aims at comparing biogeochemical processes in a Vallisneria spiralis meadow and in unvegetated sediments in the upper reach of the Mincio River (Northern Italy. The main hypothesis of this work is that meadows of rooted macrophytes affect benthic metabolism, enhancing capacity to retain nutrients (assimilation and dissipate (denitrification nitrogen loadings. In order to highlight how plants affect benthic processes in the riverbed, oxygen, dissolved inorganic carbon (DIC, soluble reactive phosphorus (SRP and inorganic nitrogen fluxes, together with denitrification rates, were measured from February to November 2007 in intact cores collected from stands of V. spiralis and bare sediments. V. spiralis biomass, elemental composition and growth rates were concurrently measured. Macrophyte biomass ranged from 60 to 120 g m-2 (as dry matter; growth rates followed a seasonal pattern from 0.001 in winter up to 0.080 d-1 in summer. On an annual basis, the macrophyte meadow was autotrophic with net O2 production and dissolved inorganic carbon uptake, while the bare sediment was net heterotrophic. The concurrent N assimilation by macrophytes and losses through denitrification led to similar N uptake/dissipation rates, up to 2500 mmol m-2 y-1. Under the very high NO3 - concentrations of the Mincio River, the competition between primary production and denitrification processes was also avoided. A significant ammonium regeneration from sediments to the water column occurred in the V. spiralis meadow, where plant debris and particulate matter accumulated. Here, SRP was also released into the water column, whilst in the bare sediment SRP fluxes were close to zero. Overall, V. spiralis affected the benthic metabolism enhancing the ecosystem capacity to control nitrogen contamination. However, the actual N removal rates were not sufficient to mitigate the pollution discharge.

  17. Clinical outcomes with drug-eluting and bare-metal stents in patients with ST-segment elevation myocardial infarction

    DEFF Research Database (Denmark)

    Palmerini, Tullio; Biondi-Zoccai, Giuseppe; Della Riva, Diego

    2013-01-01

    The authors investigated the relative safety and efficacy of different drug-eluting stents (DES) and bare metal stents (BMS) in patients with ST-segment elevation myocardial infarction (STEMI) using a network meta-analysis.......The authors investigated the relative safety and efficacy of different drug-eluting stents (DES) and bare metal stents (BMS) in patients with ST-segment elevation myocardial infarction (STEMI) using a network meta-analysis....

  18. Space demostration of bare electrodynamic tape-tether technology on the sounding rocket S520-25

    OpenAIRE

    Fujii, Hironori; Watanabe, Takeo; Sahara, Hironori; Kojima, Hirohisa; Takehara, Shoichiro; Yamagiwa, Yoshiki; Sasaki, Susumu; Abe, Takumi; Tanaka, Koji; Oyama, Khoichiro; Jhonson, Les; Khazanov, V.; Sanmartín Losada, Juan Ramón; Charro, Mario; Kruijff, Michiel

    2011-01-01

    A spaceflight validation of bare electro dynamic tape tether technology was conducted. A S520-25 sounding rocket was launched successfully at 05:00am on 31 August 2010 and successfully deployed 132.6m of tape tether over 120 seconds in a ballistic flight. The electrodynamic performance of the bare tape tether employed as an atmospheric probe was measured. Flight results are introduced through the present progressive report of the demonstration and the results of flight experiment are ex...

  19. T-REX: Bare electro-dynamic tape-tether technology experimetn on sounding rocket S520

    OpenAIRE

    Watanabe, Takeo; Fujii, Hironori; Kusagaya, Tairo; Sahara, Hironori; Kojima, Hirohisa; Takehara, Shoichiro; Yamagiwa, Yoshiki; Sasaki, Susumu; Abe, Takumi; Tanaka, Koji; Oyama, Khoichiro; Ebinuma, Takuji; Johson, Les; Khazanov, George; Sanmartín Losada, Juan Ramón

    2012-01-01

    The project to verify the performance of space tether technology was successfully demonstrated by the launch of the sounding rocket S520 the 25tu. The project is the space demonstration of science and engineering technologies of a bare tape electrodynamic tether (EDT) in the international campaign between Japan, USA, Europe and Australia. Method of "Inverse ORIGAMI (Tape tether folding)" was employed in order to deploy the bare tape EDT in a short period time of the suborbital flight. The ...

  20. Outcomes of Prosthetic Hemodialysis Grafts after Deployment of Bare Metal versus Covered Stents at the Venous Anastomosis

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Charles Y., E-mail: charles.kim@duke.edu; Tandberg, Daniel J.; Rosenberg, Michael D.; Miller, Michael J.; Suhocki, Paul V.; Smith, Tony P. [Duke University Medical Center, Division of Vascular and Interventional Radiology (United States)

    2012-08-15

    Purpose: To compare postintervention patency rates after deployment of bare metal versus covered stents across the venous anastomosis of prosthetic arteriovenous (AV) grafts. Methods: Review of our procedural database over a 6 year period revealed 377 procedures involving stent deployment in an AV access circuit. After applying strict inclusion criteria, our study group consisted of 61 stent deployments in 58 patients (median age 58 years, 25 men, 33 women) across the venous anastomosis of an upper extremity AV graft circuit that had never been previously stented. Both patent and thrombosed AV access circuits were retrospectively analyzed. Within the bare metal stent group, 20 of 32 AV grafts were thrombosed at initial presentation compared to 18 of 29 AV grafts in the covered stent group. Results: Thirty-two bare metal stents and 29 covered stents were deployed across the venous anastomosis. The 3, 6, and 12 months primary access patency rates for bare metal stents were not significantly different than for covered stents: 50, 41, and 22 % compared to 59, 52, and 29 %, respectively (p = 0.21). The secondary patency rates were also not significantly different: 78, 78, and 68 % for bare metal stents compared to 76, 69, and 61 % for covered stents, respectively (p = 0.85). However, covered stents demonstrated a higher primary stent patency rate than bare metal stents: 100, 85, and 70 % compared to 75, 67, and 49 % at 3, 6, and 12 months (p < 0.01). Conclusion: The primary and secondary access patency rates after deployment of bare metal versus covered stents at the venous anastomosis were not significantly different. However, bare metal stents developed in-stent stenoses significantly sooner.

  1. Surrounding Moving Obstacle Detection for Autonomous Driving Using Stereo Vision

    Directory of Open Access Journals (Sweden)

    Hao Sun

    2013-06-01

    Full Text Available Detection and tracking surrounding moving obstacles such as vehicles and pedestrians are crucial for the safety of mobile robotics and autonomous vehicles. This is especially the case in urban driving scenarios. This paper presents a novel framework for surrounding moving obstacles detection using binocular stereo vision. The contributions of our work are threefold. Firstly, a multiview feature matching scheme is presented for simultaneous stereo correspondence and motion correspondence searching. Secondly, the multiview geometry constraint derived from the relative camera positions in pairs of consecutive stereo views is exploited for surrounding moving obstacles detection. Thirdly, an adaptive particle filter is proposed for tracking of multiple moving obstacles in surrounding areas. Experimental results from real‐world driving sequences demonstrate the effectiveness and robustness of the proposed framework.

  2. Surrounding Moving Obstacle Detection for Autonomous Driving Using Stereo Vision

    Directory of Open Access Journals (Sweden)

    Hao Sun

    2013-06-01

    Full Text Available Detection and tracking surrounding moving obstacles such as vehicles and pedestrians are crucial for the safety of mobile robotics and autonomous vehicles. This is especially the case in urban driving scenarios. This paper presents a novel framework for surrounding moving obstacles detection using binocular stereo vision. The contributions of our work are threefold. Firstly, a multiview feature matching scheme is presented for simultaneous stereo correspondence and motion correspondence searching. Secondly, the multiview geometry constraint derived from the relative camera positions in pairs of consecutive stereo views is exploited for surrounding moving obstacles detection. Thirdly, an adaptive particle filter is proposed for tracking of multiple moving obstacles in surrounding areas. Experimental results from real-world driving sequences demonstrate the effectiveness and robustness of the proposed framework.

  3. Traditional Indian custOInS surrounding birth

    African Journals Online (AJOL)

    traditional custOIns surrounding birth in Indian culture. ... conception, pregnancy, birth and the early months ofparenthood. .... house attended by a traditional birth attendant of a ..... Spiritual components play a dominant role in traditional.

  4. Glow phenomenon surrounding the vertical stabilizer and OMS pods

    Science.gov (United States)

    1994-01-01

    This 35mm frame, photographed as the Space Shuttle Columbia was orbiting Earth during a 'night' pass, documents the glow phenomenon surrounding the vertical stabilizer and the Orbital Maneuvering System (OMS) pods of the spacecraft.

  5. VARIABILITY OF ATMOSPHERIC CO2 OVER INDIA AND SURROUNDING OCEANS AND CONTROL BY SURFACE FLUXES

    Directory of Open Access Journals (Sweden)

    R. K. Nayak

    2012-08-01

    Full Text Available In the present study, seasonal and inter-annual variability of atmospheric CO2 concentration over India and surrounding oceans during 2002–2010 derived from Atmospheric InfrarRed Sounder observation and their relation with the natural flux exchanges over terrestrial Indian and surrounding oceans were analyzed. The natural fluxes over the terrestrial Indian in the form of net primary productivity (NPP were simulated based on a terrestrial biosphere model governed by time varying climate parameters (solar radiation, air temperature, precipitation etc and satellite greenness index together with the land use land cover and soil attribute maps. The flux exchanges over the oceans around India (Tropical Indian Ocean: TIO were calculated based on a empirical model of CO2 gas dissolution in the oceanic water governed by time varying upper ocean parameters such as gradient of partial pressure of CO2 between ocean and atmosphere, winds, sea surface temperature and salinity. Comparison between the variability of atmospheric CO2 anomaly with the anomaly of surface fluxes over India and surrounding oceans suggests that biosphere uptake over India and oceanic uptake over the south Indian Ocean could play positive role on the control of seasonal variability of atmospheric carbon dioxide growth rate. On inter-annual scale, flux exchanges over the tropical north Indian Ocean could play positive role on the control of atmospheric carbon dioxide growth rate.

  6. Experiencias de mujeres migrantes que trabajan en bares de la frontera Chiapas-Guatemala

    Directory of Open Access Journals (Sweden)

    Carmen FERNÁNDEZ-CASANUEVA

    2009-01-01

    Full Text Available Se presenta una exploración de la experiencia migratoria de las mujeres centroamericanas que laboran en bares en la frontera sur de México, entre Chiapas y Guatemala, desde el momento en que toman la decisión de migrar, hasta el momento en que han cruzado la frontera y se encuentran trabajando en ese sector. Se busca comprender la relación dinámica que estas mujeres tienen con su contexto, y también el rol de las redes sociales durante el proceso.

  7. Soft food&drink, sistema para restaurantes bares y cafeterías

    OpenAIRE

    Correa Barrera, Alexandra; Solano Veloz, Seila; Freire Cobo, Lenin Eduardo

    2009-01-01

    El documento que se presenta a continuación, contiene el plan de negocios realizado por la empresa Innova Software S.A. empresa desarrolladora de software, encaminada a proveer soluciones a problemas existentes en diversos campos de la industria, a través del diseño y desarrollo de sistemas informáticos. El plan de negocios ofrece información del primer producto desarrollado por nuestra empresa denominado Soft Food&Drink, Sistema de Control de Restaurantes, Bares y Cafeterías; el cual fu...

  8. Numerical solution of uncertain neutron diffusion equation for imprecisely defined homogeneous triangular bare reactor

    Indian Academy of Sciences (India)

    S Nayak; S Chakraverty

    2015-10-01

    In this paper, neutron diffusion equation of a triangular homogeneous bare reactor with uncertain parameters has been investigated. Here the involved parameters viz. geometry of the reactor, diffusion coefficient and absorption coefficient, etc. are uncertain and these are considered as fuzzy. Fuzzy values are handled through limit method which was defined for interval computations. The concept of fuzziness is hybridised with traditional finite element method to propose fuzzy finite element method. The proposed fuzzy finite element method has been used to obtain the uncertain eigenvalues of the said problem. Further these uncertain eigenvalues are compared with the traditional finite element method in special cases.

  9. Low-frequency noise in bare SOI wafers: Experiments and model

    Science.gov (United States)

    Pirro, L.; Ionica, I.; Cristoloveanu, S.; Ghibaudo, G.

    2016-11-01

    Low-frequency noise (LFN) measurements are largely used for interface quality characterization in MOSFETs. In this work, a detailed investigation of LFN technique applied to pseudo-MOSFETs in bare silicon-on-insulator (SOI) substrates is provided. A physical model capable to describe the experimental results is proposed and validated using different die areas and inter-probe distances. The effective silicon area contributing to the noise signal, the impact of defects induced by probes and the possibility to extract interface trap density are addressed.

  10. Safety and efficacy of everolimus-eluting stents for bare-metal in-stent restenosis

    Energy Technology Data Exchange (ETDEWEB)

    Ota, Hideaki [Division of Interventional Cardiology, MedStar Washington Hospital Center, Washington, DC 20010 (United States); Mahmoudi, Michael [University of Surrey, Guildford Road, Surrey, GU2-7XH (United Kingdom); Torguson, Rebecca; Satler, Lowell F.; Suddath, William O.; Pichard, Augusto D. [Division of Interventional Cardiology, MedStar Washington Hospital Center, Washington, DC 20010 (United States); Waksman, Ron, E-mail: ron.waksman@medstar.net [Division of Interventional Cardiology, MedStar Washington Hospital Center, Washington, DC 20010 (United States)

    2015-04-15

    Objective: The aim of this study was to compare the safety and efficacy of the everolimus-eluting stents (EES) with the paclitaxel-eluting stent (PES) and sirolimus-eluting stent (SES) for the treatment of bare-metal in-stent restenosis. Background: The optimal treatment for bare-metal in-stent restenosis remains controversial. Methods: The study cohort comprised 322 consecutive patients (543 lesions) who presented with bare-metal in-stent restenosis to our institution and underwent coronary artery stent implantation with EES (114 patients; 181 lesions), PES (65 patients; 116 lesions) and SES (143 patients; 246 lesions). The analyzed clinical parameters were the 1-year rates of death, Q-wave myocardial infarction (MI), target lesion revascularization (TLR), target vessel revascularization (TVR), definite stent thrombosis (ST) and major adverse cardiac events (MACE) defined as the composite of death, MI, or TLR at 1-year. Results: The three groups were well matched for the conventional risk factors except for age and chronic kidney disease. The 1-year analyzed clinical parameters were similar in the three groups: death (EES = 3.5%, PES = 4.6%, SES = 4.2%; p = 0.94), MI (EES = 3.5%, PES = 6.3%, SES = 2.1%; p = 0.31), TLR (EES = 9.8%, PES = 9.5%, SES = 5.7%; p = 0.42), TVR (EES = 14.3%, PES = 11.1%, SES = 11.3%; p = 0.74), definite ST (EES = 0.9%, PES = 3.1%, SES = 3.5%; p = 0.38) and MACE (EES = 14.0%, PES = 15.4%, SES = 10.5%; p = 0.54). Male gender (hazard ratio = 0.47; 95% confidence interval = 0.25–0.88) and number of treated lesions (hazard ratio = 1.47; 95% confidence interval = 1.06–2.05) were found to be independent predictors of MACE. Conclusion: The results of the present study indicate that EES may provide similar safety and efficacy as first generation DES for the treatment of patients presenting with bare-metal in-stent restenosis.

  11. Low-Energy Rate Enhancement in Recombination Processes of Electrons into Bare Uranium Ions

    Institute of Scientific and Technical Information of China (English)

    WU Yong; ZENG Si-Liang; DUAN Bin; YAN Jun; WANG Jian-Guo; DONG Chen-Zhong; MA Xin-Wen

    2007-01-01

    Based on the Dirac-Fork-Slater method combined with the multichannel quantum defect theory, the recombination processes of electrons into bare uranium ions (U92+) are investigated in the relative energy range close to zero, and the x-ray spectrum emitted in the direct radiative recombination and cascades processes are simulated. Compared with the recent measurement, it is found that the rate enhancement comes from the additional populations on high Rydberg states. These additional populations may be produced by other recombination mechanisms, such as the external electric-magnetic effects and the many-body correlation effects, which still remains an open problem.

  12. Introducing the notion of bare and effective mass via Newton's second law of motion

    CERN Document Server

    Pinto, M B

    2005-01-01

    The concepts of bare and effective mass are widely used within modern physics. Their meaning is discussed in advanced undergraduate and graduate courses such as solid state physics, nuclear physics and quantum field theory. Here, I discuss how these concepts may be introduced, at a very early stage, together with the discussion of Newton's second law of motion for a sliding block. The setting up of a simple equation for the effective mass will allow instructors to discuss how external parameters, such as the temperature, influence this quantity. By developing the same equation as a power series one may also discuss perturbation theory and introduce Feynman diagrams.

  13. Cultura de calidad en centros nocturnos y bares en México. Caso puerto de Veracruz

    OpenAIRE

    Herrera, Carlos; Universidad Popular Autónoma del Estado de Puebla; Vargas-Hernández, José G.; Universidad de Guadalajara

    2016-01-01

    El sector turismo ha tenido un auge creciente en fechas recientes y en este ámbito la competitividad ha sido un asunto ampliamente analizado. La calidad es un elemento importante para incrementar la competitividad en bares y centros nocturnos y en ella el personal de la empresa es una pieza clave. Su participación en el diseño de elementos de ambiente, servicio y mercadotecnia induce un incremento en la competitividad de las empresas del sector industrial al influir directamente en la experie...

  14. Bare metal or drug-eluting stent implantation in last remaining vessel PCI? A serious dilemma.

    Science.gov (United States)

    Zhang, Lei; Zhu, Jianhua; Kiemeneij, Ferdinand

    2009-04-01

    This case report describes the treatment of an old male diabetic patient with last remaining vessel coronary artery disease and poor left ventricular function. In presence of an old occlusion of the left main coronary artery, a subtotal stenosis of a dominant right coronary artery required angioplasty. After ample consideration it was decided to implant a bare metal stent (BMS) instead of a drug-eluting stent (DES). The major reason was the fear for early discontinuation of clopidogrel in case a drug-eluting stent was placed. The procedure and follow-up are described followed by an overview of current literature concerning similar pathology.

  15. Surrounding Moving Obstacle Detection for Autonomous Driving Using Stereo Vision

    OpenAIRE

    Hao Sun; Huanxin Zou; Shilin Zhou; Cheng Wang; Naser El-Sheimy

    2013-01-01

    Detection and tracking surrounding moving obstacles such as vehicles and pedestrians are crucial for the safety of mobile robotics and autonomous vehicles. This is especially the case in urban driving scenarios. This paper presents a novel framework for surrounding moving obstacles detection using binocular stereo vision. The contributions of our work are threefold. Firstly, a multiview feature matching scheme is presented for simultaneous stereo correspondence and motion correspondence searc...

  16. "Tilt" in color space: Hue changes induced by chromatic surrounds.

    Science.gov (United States)

    Klauke, Susanne; Wachtler, Thomas

    2015-01-01

    The perceived color of a chromatic stimulus is influenced by the chromaticity of its surround. To investigate these influences along the dimension of hue, we measured hue changes induced in stimuli of different hues by isoluminant chromatic surrounds. Generally, induced hue changes were directed in color space away from the hue of the inducing surround and depended on the magnitude on the hue difference between stimulus and surround. With increasing difference in hue between stimulus and surround, induced hue changes increased up to a maximum and then decreased for larger differences. This qualitative pattern was similar for different inducers, but quantitatively, induction was weaker along some directions in cone-opponent color space than along other directions. The strongest induction effects were found along an oblique, blue-yellow axis that corresponds to the daylight axis. The overall pattern of the induction effect shows similarities to the well-known tilt effect, where shifts in perceived angle of oriented stimuli are induced by oriented surrounds. This suggests analogous neural representations and similar mechanisms of contextual processing for different visual features such as orientation and color.

  17. Control of Formation of Lithological Reservoirs by Surrounding Mudstone

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Taking the Jiyang depression as an example, this paper discusses the control of the formation of lithological reservoir by surrounding rocks by integrated application of geological analysis, physical simulation, and the analysis of oil & gas accumulation mechanism. Geological statistical shows that the major burial depth and interval of lithological reservoirs in the Jiyang depression are related to the hydrocarbon generation in and expulsion from the Lower Tertiary source rocks and the time of the formation of most lithological reservoirs coincides with the peak of hydrocarbon generation and expulsion. The lithological traps located in the center of effective source rocks are propitious to high oil saturation than those located on the margin of effective source rocks. The hydrocarbon charge degree of the lithological reservoir has a positive correlation with the intensity of hydrocarbon expulsion from surrounding source rocks.Geological analyses and NMR experiments also show that the oil saturation of surrounding source rocks control the hydrocarbon potential of lithological traps, and a critical value for oil saturation of surrounding mudstone is required, that is, when the oil saturation of surrounding mudstone is lower than this critical value, no oil and gas accumulate in the lithological trap. The control of surrounding mudstone on the oil-bearing properties of lithological reservoirs is also analyzed by the mechanisms of hydrocarbon generation and expulsion as well as accumulation.

  18. Response of Surface Soil Hydrology to the Micro-Pattern of Bio-Crust in a Dry-Land Loess Environment, China.

    Science.gov (United States)

    Wei, Wei; Yu, Yun; Chen, Liding

    2015-01-01

    The specific bio-species and their spatial patterns play crucial roles in regulating eco-hydrologic process, which is significant for large-scale habitat promotion and vegetation restoration in many dry-land ecosystems. Such effects, however, are not yet fully studied. In this study, 12 micro-plots, each with size of 0.5 m in depth and 1 m in length, were constructed on a gentle grassy hill-slope with a mean gradient of 8° in a semiarid loess hilly area of China. Two major bio-crusts, including mosses and lichens, had been cultivated for two years prior to the field simulation experiments, while physical crusts and non-crusted bare soils were used for comparison. By using rainfall simulation method, four designed micro-patterns (i.e., upper bio-crust and lower bare soil, scattered bio-crust, upper bare soil and lower bio-crust, fully-covered bio-crust) to the soil hydrological response were analyzed. We found that soil surface bio-crusts were more efficient in improving soil structure, water holding capacity and runoff retention particularly at surface 10 cm layers, compared with physical soil crusts and non-crusted bare soils. We re-confirmed that mosses functioned better than lichens, partly due to their higher successional stage and deeper biomass accumulation. Physical crusts were least efficient in water conservation and erosion control, followed by non-crusted bare soils. More importantly, there were marked differences in the efficiency of the different spatial arrangements of bio-crusts in controlling runoff and sediment generation. Fully-covered bio-crust pattern provides the best option for soil loss reduction and runoff retention, while a combination of upper bio-crust and lower bare soil pattern is the least one. These findings are suggested to be significant for surface-cover protection, rainwater infiltration, runoff retention, and erosion control in water-restricted and degraded natural slopes.

  19. Estimating preseason irrigation losses by characterizing evaporation of effective precipitation under bare soil conditions using large weighing lysimeters

    Science.gov (United States)

    Irrigation scheduling is one of the most cost effective means of conserving limited groundwater resources, particularly in semi-arid regions. Effective precipitation, or the net amount of water from precipitation that can be used in field water balance equations, is essential to accurate and effecti...

  20. Characteristics and diversity of Rhizoctonia spp. population in soil of selected forest bare-root nurseries in Poland

    Directory of Open Access Journals (Sweden)

    Marta Bełka

    2014-12-01

    Full Text Available Fourty three Rhizoctonia isolates obtained from four forest nurseries situated in the Wielkopolska region (central-western Poland has been proved as multinucleate (anamorph – R. solani. They represented four anastomosis groups (AG: AG1-IC, AG-5, AG4-HG2 and AG2-1. Three AGs were found in Jarocin nursery (AG-5, AG4-HG2 and AG2-1, two in Łopuchówko (AG-5 and AG4-HG2 and one in Konstantynowo (AG1-IC and Pniewy (AG-5. All isolates were highly pathogenic to Scots pine (Pinus sylvestris seedlings and pose a large damping-off threat to the seedlings in the nurseries with single AG and in those where more AGs exists.

  1. Role of nutrient amendments in the success of half-moon soil and water conservation practice in semiarid Burkina Faso

    NARCIS (Netherlands)

    Zougmoré, R.; Kambou, N.F.; Zida, Z.

    2003-01-01

    The half-moon technique has been recently introduced in northern Burkina Faso as a method for the rehabilitation of sealed and crusted bare soils locally called zipellé. As this technique, like zaï and mulching practices, interested many farmers, a trial was conducted to study the effect on soil pro

  2. Niche Filtering of Bacteria in Soil and Rock Habitats of the Colorado Plateau Desert, Utah, USA

    Science.gov (United States)

    Lee, Kevin C.; Archer, Stephen D. J.; Boyle, Rachel H.; Lacap-Bugler, Donnabella C.; Belnap, Jayne; Pointing, Stephen B.

    2016-01-01

    A common feature of microbial colonization in deserts is biological soil crusts (BSCs), and these comprise a complex community dominated by Cyanobacteria. Rock substrates, particularly sandstone, are also colonized by microbial communities. These are separated by bare sandy soil that also supports microbial colonization. Here we report a high-throughput sequencing study of BSC and cryptoendolith plus adjacent bare soil communities in the Colorado Plateau Desert, Utah, USA. Bare soils supported a community with low levels of recoverable DNA and high evenness, whilst BSC yielded relatively high recoverable DNA, and reduced evenness compared to bare soil due to specialized crust taxa. The cryptoendolithic community displayed the greatest evenness but the lowest diversity, reflecting the highly specialized nature of these communities. A strong substrate-dependent pattern of community assembly was observed, and in particular cyanobacterial taxa were distinct. Soils were virtually devoid of photoautotrophic signatures, BSC was dominated by a closely related group of Microcoleus/Phormidium taxa, whilst cryptoendolithic colonization in sandstone supported almost exclusively a single genus, Chroococcidiopsis. We interpret this as strong evidence for niche filtering of taxa in communities. Local inter-niche recruitment of photoautotrophs may therefore be limited and so communities likely depend significantly on cyanobacterial recruitment from distant sources of similar substrate. We discuss the implication of this finding in terms of conservation and management of desert microbiota. PMID:27725810

  3. Forest Fragments Surrounded by Sugar Cane Are More Inhospitable to Terrestrial Amphibian Abundance Than Fragments Surrounded by Pasture

    Directory of Open Access Journals (Sweden)

    Paula Eveline Ribeiro D’Anunciação

    2013-01-01

    Full Text Available In recent years, there has been increasing interest in matrix-type influence on forest fragments. Terrestrial amphibians are good bioindicators for this kind of research because of low vagility and high philopatry. This study compared richness, abundance, and species composition of terrestrial amphibians through pitfall traps in two sets of semideciduous seasonal forest fragments in southeastern Brazil, according to the predominant surrounding matrix (sugar cane and pasture. There were no differences in richness, but fragments surrounded by sugar cane had the lowest abundance of amphibians, whereas fragments surrounded by pastures had greater abundance. The most abundant species, Rhinella ornata, showed no biometric differences between fragment groups but like many other amphibians sampled showed very low numbers of individuals in fragments dominated by sugar cane fields. Our data indicate that the sugar cane matrix negatively influences the community of amphibians present in fragments surrounded by this type of land use.

  4. Investigating soil controls on soil moisture spatial variability: Numerical simulations and field observations

    Science.gov (United States)

    Wang, Tiejun; Franz, Trenton E.; Zlotnik, Vitaly A.; You, Jinsheng; Shulski, Martha D.

    2015-05-01

    Due to its complex interactions with various processes and factors, soil moisture exhibits significant spatial variability across different spatial scales. In this study, a modeling approach and field observations were used to examine the soil control on the relationship between mean (θ bar) and standard deviation (σθ) of soil moisture content. For the numerical experiments, a 1-D vadose zone model along with van Genuchten parameters generated by pedotransfer functions was used for simulating soil moisture dynamics under different climate and surface conditions. To force the model, hydrometeorological and physiological data that spanned over three years from five research sites within the continental US were used. The modeling results showed that under bare surface conditions, different forms of the θ bar -σθ relationship as observed in experimental studies were produced. For finer soils, a positive θ bar -σθ relationship gradually changed to an upward convex and a negative one from arid to humid conditions; whereas, a positive relationship existed for coarser soils, regardless of climatic conditions. The maximum σθ for finer soils was larger under semiarid conditions than under arid and humid conditions, while the maximum σθ for coarser soils increased with increasing precipitation. Moreover, vegetation tended to reduce θ bar and σθ, and thus affected the θ bar -σθ relationship. A sensitivity analysis was also conducted to examine the controls of different van Genuchten parameters on the θ bar -σθ relationship under bare surface conditions. It was found that the residual soil moisture content mainly affected σθ under dry conditions, while the saturated soil moisture content and the saturated hydraulic conductivity largely controlled σθ under wet conditions. Importantly, the upward convex θ bar -σθ relationship was mostly caused by the shape factor n that accounts for pore size distribution. Finally, measured soil moisture data from a

  5. Determining soil moisture and soil properties in vegetated areas by assimilating soil temperatures

    Science.gov (United States)

    Dong, Jianzhi; Steele-Dunne, Susan C.; Ochsner, Tyson E.; van de Giesen, Nick

    2016-06-01

    This study addresses two critical barriers to the use of Passive Distributed Temperature Sensing (DTS) for large-scale, high-resolution monitoring of soil moisture. In recent research, a particle batch smoother (PBS) was developed to assimilate sequences of temperature data at two depths into Hydrus-1D to estimate soil moisture as well as soil thermal and hydraulic properties. However, this approach was limited to bare soil and assumed that the cable depths were perfectly known. In order for Passive DTS to be more broadly applicable as a soil hydrology research and remote sensing soil moisture product validation tool, it must be applicable in vegetated areas. To address this first limitation, the forward model (Hydrus-1D) was improved through the inclusion of a canopy energy balance scheme. Synthetic tests were used to demonstrate that without the canopy energy balance scheme, the PBS estimated soil moisture could be even worse than the open loop case (no assimilation). When the improved Hydrus-1D model was used as the forward model in the PBS, vegetation impacts on the soil heat and water transfer were well accounted for. This led to accurate and robust estimates of soil moisture and soil properties. The second limitation is that, cable depths can be highly uncertain in DTS installations. As Passive DTS uses the downward propagation of heat to extract moisture-related variations in thermal properties, accurate estimates of cable depths are essential. Here synthetic tests were used to demonstrate that observation depths can be jointly estimated with other model states and parameters. The state and parameter results were only slightly poorer than those obtained when the cable depths were perfectly known. Finally, in situ temperature data from four soil profiles with different, but known, soil textures were used to test the proposed approach. Results show good agreement between the observed and estimated soil moisture, hydraulic properties, thermal properties, and

  6. Photo-physical properties enhancement of bare and core-shell quantum dots

    Energy Technology Data Exchange (ETDEWEB)

    Mumin, Md Abdul, E-mail: pcharpentier@eng.uwo.ca; Akhter, Kazi Farida, E-mail: pcharpentier@eng.uwo.ca; Charpentier, Paul A., E-mail: pcharpentier@eng.uwo.ca [Chemical and Biochemical Engineering, Western University, London Ontario (Canada)

    2014-03-31

    Semiconductor nanocrystals (NCs) (also known as quantum dots, QDs) have attracted immense attention for their size-tunable optical properties that makes them impressive candidates for solar cells, light emitting devices, lasers, as well as biomedical imaging. However monodispersity, high and consistent photoluminescence, photostability, and biocompatibility are still major challenges. This work focuses on optimizing the photophysical properties and biocompatibility of QDs by forming core-shell nanostructures and their encapsulation by a carrier. Highly luminescent CdS and CdS-ZnS core-shell QDs with 5 nm sizes were synthesized using a facile approach based on pyrolysis of the single molecule precursors. After capping the CdS QDs with a thin layer of ZnS to reduce toxicity, the photoluminescence and photostability of the core-shell QDs was significantly enhanced. To make both the bare and core/shell structure QDs more resistant against photochemical reactions, a mesoporous silica layer was grown on the QDs through a reverse microemulsion technique based on hydrophobic interaction. This encapsulation enhanced the quantum yield and photostability compared to the bare QDs by providing much stronger resistance to oxidation and Oswald ripening of QDs. Encapsulation also improved biocompatibility of QDs that was evaluated with human umbilical vein endothelial cell lines (HUVEC)

  7. Synthesis and Characterizations of Bare CdS Nanocrystals Using Chemical Precipitation Method for Photoluminescence Application

    Directory of Open Access Journals (Sweden)

    H. L. Lee

    2009-01-01

    Full Text Available Bare cadmium sulfide (CdS nanocrystals were successfully synthesized by the thermolysis of a single-source organometallic precursor, cadmium chloride hemipentahydrate (CdCl2⋅2.5H2O with thiourea in ethanol. The microstructure of the CdS samples was characterized using XRD, TEM, and Raman spectroscopy. The XRD's results showed that there was a transformation from cubic to hexagonal crystalline phase when higher mass of CdCl2⋅2.5H2O was used. Further experimental with different Cd2+ source showed ion Cl− originated from CdCl2⋅2.5H2O attributed to this crystalline phase transformation. The UV-Visible analysis indicated that quantum confinement effect took place when compared to the bulk CdS. However, the photoluminescence experiments revealed that the red-light emission was observed in all samples. This finding could be ascribed to deep trap defects that were due to sulfur vacancies as suggested by XPS and also the fact that the bare CdS nanoparticles are in contact with each other as shown in the TEM images.

  8. "O complô da torcida": futebol e performance masculina em bares

    Directory of Open Access Journals (Sweden)

    Édison Gastaldo

    2005-12-01

    Full Text Available Este artigo busca discutir aspectos da interação social ocorrente em bares onde são transmitidas partidas de futebol, em particular aqueles relacionados a performances de gênero. Os dados analisados referem-se a pesquisa etnográfica em curso desde o início de 2004, em bares da região metropolitana de Porto Alegre. São destacadas três modalidades performáticas ocorrentes no setting pesquisado: a presença no bar, os desafios verbais entre participantes e a teatralização jocosa. Considero que esses elementos - entre outros - revelam aspectos do complexo campo de significados relativos à masculinidade em nossa sociedade, compondo parte do fenômeno a que denomino "relações jocosas futebolísticas".This paper issues some topics of the social interaction occurrant in bars where football matches are transmitted, particularly aspects of gender performance. The data analysed refer to an ethnographic fieldwork being held since the beginning of 2004 in bars of the Greater Porto Alegre area, in Brazil. Three performatic modalities are discussed: the presence on the setting as performance, verbal challenges between the participants and joking dramatizations. I consider that these elements - among others - reveal part of the complex field of meanings related to masculinity in Brazilian society, being a constitutive part of the phenomenon that I call "football joking relationships".

  9. Photo-physical properties enhancement of bare and core-shell quantum dots

    Science.gov (United States)

    Mumin, Md Abdul; Akhter, Kazi Farida; Charpentier, Paul A.

    2014-03-01

    Semiconductor nanocrystals (NCs) (also known as quantum dots, QDs) have attracted immense attention for their size-tunable optical properties that makes them impressive candidates for solar cells, light emitting devices, lasers, as well as biomedical imaging. However monodispersity, high and consistent photoluminescence, photostability, and biocompatibility are still major challenges. This work focuses on optimizing the photophysical properties and biocompatibility of QDs by forming core-shell nanostructures and their encapsulation by a carrier. Highly luminescent CdS and CdS-ZnS core-shell QDs with 5 nm sizes were synthesized using a facile approach based on pyrolysis of the single molecule precursors. After capping the CdS QDs with a thin layer of ZnS to reduce toxicity, the photoluminescence and photostability of the core-shell QDs was significantly enhanced. To make both the bare and core/shell structure QDs more resistant against photochemical reactions, a mesoporous silica layer was grown on the QDs through a reverse microemulsion technique based on hydrophobic interaction. This encapsulation enhanced the quantum yield and photostability compared to the bare QDs by providing much stronger resistance to oxidation and Oswald ripening of QDs. Encapsulation also improved biocompatibility of QDs that was evaluated with human umbilical vein endothelial cell lines (HUVEC).

  10. Ice Formation via Deposition Mode Nucleation on Bare and Alcohol-covered Graphite Surfaces

    CERN Document Server

    Kong, Xiangrui; Thomson, Erik S; Pettersson, Jan B C

    2013-01-01

    Deposition of water on aerosol particles contributes to ice cloud formation in the atmosphere with implications for the water cycle and climate on Earth. The heterogeneous ice nucleation process is influenced by physico-chemical properties of the substrate, but the mechanisms remain incompletely understood. Here, we report on ice formation on bare and alcohol-covered graphite at temperatures from 175 to 213 K, probed by elastic helium and light scattering. Water has a low wettability on bare and butanol-covered graphite resulting in the growth of rough ice surfaces. In contrast, pre-adsorbed methanol provides hydrophilic surface sites and results in the formation of smooth crystalline ice; an effect that is pronounced also for sub-monolayer methanol coverages. The alcohols primarily reside at the ice surface and at the ice-graphite interface with a minor fraction being incorporated into the growing ice structures. Methanol has no observable effect on gas/solid water vapor exchange whereas butanol acts as a tr...

  11. Performance of bare high-purity germanium detectors in liquid argon for the GERDA experiment

    CERN Document Server

    Heider, Marik Barnabé; Chkvorets, Oleg; Di Vacri, Assunta; Gusev, Konstantin; Schönert, Stefan; Shirchenko, Mark

    2008-01-01

    The GERmanium Detector Array, GERDA, will search for neutrinoless double beta decay in 76Ge at the National Gran Sasso Laboratory of the INFN. Bare high-purity germanium detectors enriched in 76Ge will be submerged in liquid argon serving simultaneously as a shield against external radioactivity and as a cooling medium. In GERDA Phase-I, reprocessed enriched-Ge detectors, which were previously operated by the Heidelberg-Moscow and IGEX collaborations, will be redeployed. Before operating the enriched detectors, tests are performed with non-enriched bare HPGe detectors in the GERDA underground Detector Laboratory to test the Phase-I detector assembly, the detector handling protocols, the refurbishment technology and to study the long-term stability in liquid argon. The leakage currents in liquid argon and liquid nitrogen have been extensively studied under varying gamma irradiation conditions. In total three non-enriched high-purity p-type prototype germanium detectors have been operated successfully. The dete...

  12. Probing the Surfaces of Interstellar Dust Grains: The Adsorption of CO at Bare Grain Surfaces

    CERN Document Server

    Fraser, H J; Pontoppidan, K M; Van Dishoeck, A G; Fraser, Helen J.; Bisschop, Suzanne E.; Pontoppidan, Klaus M.; Dishoeck, Alexander G.G.M. Tielens & Ewine F. van

    2004-01-01

    A solid-state feature was detected at around 2175 cm-1 towards 30 embedded young stellar objects in spectra obtained using the ESO VLT-ISAAC. We present results from laboratory studies of CO adsorbed at the surface of Zeolite wafers, where absorption bands were detected at 2177 and 2168 cm-1 (corresponding to CO chemisorbed at the Zeolite surface), and 2130 cm-1 (corresponding to CO physisorbed at the Zeolite surface), providing an excellent match to the observational data. We propose that the main carrier of the 2175-band is CO chemisorbed at bare surfaces of dust grains in the interstellar medium. This result provides the first direct evidence that gas-surface interactions do not have to result in the formation of ice mantles on interstellar dust. The strength of the 2175-band is estimated to be ~ 4 x 10-19 cm molecule-1. The abundance of CO adsorbed at bare grain surfaces ranges from 0.06 to 0.16 relative to H2O ice, which is, at most, half of the abundance (relative to H2O ice) of CO residing in H2O-domin...

  13. Imparting Barely Visible Impact Damage to a Stitched Composite Large-Scale Pressure Box

    Science.gov (United States)

    Lovejoy, Andrew E.; Przekop, Adam

    2016-01-01

    The Pultruded Rod Stitched Efficient Unitized Structure (PRSEUS) is a concept that was developed by The Boeing Company to address the complex structural design aspects associated with a pressurized hybrid wing body (HWB) aircraft configuration, which has been a focus of the NASA Environmentally Responsible Aviation Project. The NASA-Boeing structural development for the HWB aircraft culminated in testing of the multi-bay box, which is an 80%-scale representation of the pressurized center-body section. This structure was tested in the NASA Langley Research Center Combined Loads Test System facility. As part of this testing, barely visible impact damage was imparted to the interior and exterior of the test article to demonstrate compliance with a condition representative of the requirements for Category 1 damaged composite structure as defined by the Federal Aviation Regulations. Interior impacts were imparted using an existing spring-loaded impactor, while the exterior impacts were imparted using a newly designed, gravity-driven impactor. This paper describes the impacts to the test article, and the design of the gravitydriven guided-weight impactor. The guided-weight impactor proved to be a very reliable method to impart barely visible impact damage in locations which are not easily accessible for a traditional drop-weight impactor, while at the same time having the capability to be highly configurable for use on other aircraft structures.

  14. Genetic relationships between dagginess, breech bareness, and wool traits in New Zealand dual-purpose sheep.

    Science.gov (United States)

    Pickering, N K; Blair, H T; Hickson, R E; Dodds, K G; Johnson, P L; McEwan, J C

    2013-10-01

    Genetic and phenotypic parameters were estimated for dagginess, breech, wool, and fiber traits from approximately 29,500 progeny born in 2009 and 2010 in New Zealand dual-purpose ram breeding sheep flocks. Dagginess is adherence of fecal matter to the wool, and this study investigates the genetic and phenotypic correlations between dagginess and breech and wool traits. Estimates for heritability were moderate (0.21 to 0.44) for the following traits: dag score at 3 and 8 mo (DAG3, DAG8), breech bareness, wool length, wool bulk (BULK), mean fiber diameter, mean fiber diameter SD, mean fiber diameter CV, curvature (CURV), weaning weight at 3 mo, and autumn BW. Heritability estimates for fleece weight at 12 mo and proportion of medullated fibers were high (0.49 and 0.53, respectively). Dag score at 3 mo and DAG8 had low genetic and phenotypic correlations with all traits. Breech bareness had positive genetic and phenotypic correlations with CURV and BULK and mostly negative genetic correlations with all other wool traits. In summary the quantity and attributes of wool were not primary causative factors in fecal accumulation, leaving fecal consistency and composition as the major factors.

  15. Necrotizing meningoencephalitis caused by Sarcocystis falcatula in bare-faced ibis (Phimosus infuscatus).

    Science.gov (United States)

    Konradt, Guilherme; Bianchi, Matheus Viezzer; Leite-Filho, Ronaldo Viana; da Silva, Bruna Zafalon; Soares, Rodrigo Martins; Pavarini, Saulo Petinatti; Driemeier, David

    2017-02-01

    The infection by S. falcatula is commonly associated with respiratory disease in captive psittacine birds, with a few case reports of this protozoan causing encephalitis in wild birds. We describe the clinical, pathological, and molecular aspects of an infection by S. falcatula in a bare-faced ibis (Phimosus infuscatus). Clinically, wing paralysis and mild motor incoordination were observed. At necropsy, the telencephalic cortex showed multifocal to coalescing yellowish soft areas. Histologically, multifocal to coalescent nonsuppurative necrotizing meningoencephalitis of telencephalic cortex, cerebellum, and brainstem was observed. Necrotic areas showed multiple protozoan organism characteristics of Sarcocystis sp. schizonts in the cytoplasm of endothelial cells or lying free in the neuropil. Partial genetic sequences of the gene encoding cytochrome b (CYTB), the gene encoding the beta subunit of RNA polymerase (RPOB) and the first internal transcribed spacer (ITS-1) from Sarcocystis sp. schizonts revealed that the parasite had ITS-1 sequences that were 100% identical to the homologous alleles from Sarcocystis sp. shed by Didelphis albiventris in Brazil. RPOB and CYTB sequences were 100% identical to homologous of S. falcatula available in Genbank. Thus, this is the first report of necrotizing meningoencephalitis caused by S. falcatula in bare-faced ibis (P. infuscatus).

  16. Characterization of stainless steel assisted bare gold nanoparticles and their analytical potential.

    Science.gov (United States)

    López-Lorente, A I; Simonet, B M; Valcárcel, M; Eppler, S; Schindl, R; Kranz, C; Mizaikoff, B

    2014-01-01

    A simple, environmentally friendly, one-pot method to synthesize highly stable bare gold nanoparticles (AuNPs) has been developed. AuNPs have been synthesized from tetrachloroauric acid solution using steel or stainless steel as solid reducing agent, which can be reused. The proposed method yields bare gold nanoparticles at atmospheric pressure and room temperature for potentially producing large quantities. The obtained AuNPs have been characterized by SEM, TEM and AFM finding an average diameter of around 20 nm, polygonal yet nearly spherical shape and a narrow size distribution. The mechanism of reaction has been investigated by UV-vis spectroscopy, ICP-OES and EDX analysis. The obtained dispersed gold nanoparticles proved to be stable if stored a 4 °C for over four months without the addition of a stabilizing agent. Their analytical potential as SERS substrate has been demonstrated and their performance compared with that showed by citrate-coated gold nanoparticles. Thanks to their unique properties, their use as analytical tools provides analytical processes with enhanced selectivity and precision.

  17. Oralloy (93.2 235U) Bare Metal Annuli And Disks

    Energy Technology Data Exchange (ETDEWEB)

    Hummel, Andrew John [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2015-09-01

    A multitude of critical experiments with highly enriched uranium metal were conducted in the 1960s and 1970s at the Oak Ridge Critical Experiments Facility (ORCEF) in support of criticality safety operations at the Y-12 Plant. These experiments served to evaluate the storage, casting, and handling limits for the Y-12 Plant while also providing data for verification of different calculation methods and associated cross-sections for nuclear criticality safety applications. These included both solid cylinders and annuli of various diameters, interacting cylinders of various diameters, parallelepipeds, and reflected cylinders and annuli. The experiments described here involve a series of delayed critical stacks of bare oralloy HEU annuli and disks. Three of these experiments consist of stacking bare HEU annuli of varying diameters to obtain critical configurations. These annuli have nominal inner and outer diameters (ID/OD) including: 7 inches (") ID – 9" OD, 9" ID – 11" OD, 11" ID – 13" OD, and 13? ID – 15" OD. The nominal heights range from 0.125" to 1.5". The three experiments themselves range from 7" – 13", 7" – 15", and 9" – 15" in diameter, respectively. The fourth experiment ranges from 7" – 11", and along with different annuli, it also includes an 11" disk and several 7" diameter disks. All four delayed critical experiments were configured and evaluated by J. T. Mihalczo, J. J. Lynn, and D. E. McCarty from December of 1962 to February 1963 with additional information in their corresponding logbook.

  18. Spartina alterniflora invasion alters soil microbial community composition and microbial respiration following invasion chronosequence in a coastal wetland of China

    Science.gov (United States)

    Yang, Wen; Jeelani, Nasreen; Leng, Xin; Cheng, Xiaoli; An, Shuqing

    2016-05-01

    The role of exotic plants in regulating soil microbial community structure and activity following invasion chronosequence remains unclear. We investigated soil microbial community structure and microbial respiration following Spartina alterniflora invasion in a chronosequence of 6-, 10-, 17-, and 20-year-old by comparing with bare flat in a coastal wetland of China. S. alterniflora invasion significantly increased soil moisture and salinity, the concentrations of soil water-soluble organic carbon and microbial biomass carbon (MBC), the quantities of total and various types of phospholipid fatty acids (PLFAs), the fungal:bacterial PLFAs ratio and cumulative microbial respiration compared with bare flat. The highest MBC, gram-negative bacterial and saturated straight-chain PLFAs were found in 10-year-old S. alterniflora soil, while the greatest total PLFAs, bacterial and gram-positive bacterial PLFAs were found in 10- and 17-year-old S. alterniflora soils. The monounsaturated:branched PLFAs ratio declined, and cumulative microbial respiration on a per-unit-PLFAs increased following S. alterniflora invasion in the chronosequence. Our results suggest that S. alterniflora invasion significantly increased the biomass of soil various microbial groups and microbial respiration compared to bare flat soil by increasing soil available substrate, and modifying soil physiochemical properties. Soil microbial community reached the most enriched condition in the 10-year-old S. alterniflora community.

  19. 不同覆盖措施对减少枣林休眠期土壤水分损失的影响%Effects of typical mulching patterns on soil water loss in jujube land during dormancy period

    Institute of Scientific and Technical Information of China (English)

    靳姗姗; 汪星; 汪有科; 佘檀

    2016-01-01

    To promote development of the forestry and alleviate soil water depletion in forest land, a better understanding of the effects of different mulching patterns on soil moisture region, and further seeking reasonable soil conservation measures in loess hilly-gully are paramount important. As the severe soil water depletion existed in forest land in the semiarid area of the Loess Plateau, the soil water contents under 3 different mulching patterns in jujube orchard were measured using a neutron probe (CNC100 DR, ChaoNeng, China) that had been calibrated using standard methods. From March 2012 to October 2015, volumetric soil water content was measured 3 times per month. Measurements were made at the depth increment of 0.1 and 0.2 m in the 0–1 and 1–5 m soil layer, respectively. Meanwhile, the meteorological data were collected from meteorological station near the experimental plots. The objective of this study was to investigate the effects of mulching patterns on soil water loss in jujube orchard during dormancy period. The test plots were located at Yuanzhi Mount in Mizhi County, Shaanxi Province. The test plots were selected in the 11-aged dwarf close planting jujube forest in October 2011. Three level-terraces with similar slope and aspect were established on a hillslope. For each level-terrace, 4 treatments (straw mulching, plastic film mulching, gravel mulching, and bare land) were set to explore the effects of mulching patterns on soil moisture. The plot scale for 4 treatments was 2 m × 3 m and the area for each plot was thus 6 m2. The 20 cm wide and 5 m deep ditch all around each plot was excavated for each plot. To isolate the surrounding soil water and root on the test plot, about 1 mm thick plastic was used. There was no irrigation during the experiment. The thickness of the straw mulching was 10-12 cm, while the particle size of gravel mulching was 0.5-1.0 cm with a thickness about 5 cm. In the plastic film mulching treatment plot, the terrain around

  20. Effects of sulfadiazine on soil bacterial communities

    DEFF Research Database (Denmark)

    Hangler, Martin

    as fertilizers on agricultural lands they represent a route for antibiotics into the soil environment where they may persist and affect levels of antibiotic resistance in soil microbial communities over time. In this work the level of tolerance to the antibiotic sulfadiazine (SDZ) was studied in a number......-threshold, of a non-contaminated soil environment at various pH of which to compare other soils. Soil samples representing a broad range of natural pH were collected from the pH gradient at the Hoosfield acid strip, part of the long-term field experiment at the Rothamstead Research Station (UK) and exposed...... and transport of SDZ at the interphase between dewatered SDZ-amended sewage sludge and soil. SDZ was not mineralized within sludge aggregates and travelled more than 10 mm into the surrounding soil. The strongest PICT response was observed in soils fertilized with organic fertilizers or inorganic NPK fertilizer...

  1. Migraine increases centre-surround suppression for drifting visual stimuli.

    Directory of Open Access Journals (Sweden)

    Josephine Battista

    Full Text Available BACKGROUND: The pathophysiology of migraine is incompletely understood, but evidence points to hyper-responsivity of cortical neurons being a key feature. The basis of hyper-responsiveness is not clear, with an excitability imbalance potentially arising from either reduced inhibition or increased excitation. In this study, we measure centre-surround contrast suppression in people with migraine as a perceptual analogue of the interplay between inhibition and excitation in cortical areas responsible for vision. We predicted that reduced inhibitory function in migraine would reduce perceptual surround suppression. Recent models of neuronal surround suppression incorporate excitatory feedback that drives surround inhibition. Consequently, an increase in excitation predicts an increase in perceptual surround suppression. METHODS AND FINDINGS: Twenty-six people with migraine and twenty approximately age- and gender-matched non-headache controls participated. The perceived contrast of a central sinusoidal grating patch (4 c/deg stationary grating, or 2 c/deg drifting at 2 deg/sec, 40% contrast was measured in the presence and absence of a 95% contrast annular grating (same orientation, spatial frequency, and drift rate. For the static grating, similar surround suppression strength was present in control and migraine groups with the presence of the surround resulting in the central patch appearing to be 72% and 65% of its true contrast for control and migraine groups respectively (t(44 = 0.81, p = 0.42. For the drifting stimulus, the migraine group showed significantly increased surround suppression (t(44 = 2.86, p<0.01, with perceived contrast being on average 53% of actual contrast for the migraine group and 68% for non-headache controls. CONCLUSIONS: In between migraines, when asymptomatic, visual surround suppression for drifting stimuli is greater in individuals with migraine than in controls. The data provides evidence for a

  2. Precipitation Depth-Duration-Frequency Analysis for the Nevada National Security Site and Surrounding Areas

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Li [Desert Research Inst. (DRI), Las Vegas, NV (United States). Division of Hydrologic Sciences; Miller, Julianne J. [Desert Research Inst. (DRI), Las Vegas, NV (United States). Division of Hydrologic Sciences

    2016-08-01

    Accurate precipitation frequency data are important for Environmental Management Soils Activities on the Nevada National Security Site (NNSS). These data are important for environmental assessments performed for regulatory closure of Soils Corrective Action Unit (CAU) Sites, as well as engineering mitigation designs and post-closure monitoring strategies to assess and minimize potential contaminant migration from Soils CAU Sites. Although the National Oceanic and Atmospheric Administration (NOAA) Atlas 14 (Bonnin et al., 2011) provides precipitation frequency data for the NNSS area, the NNSS-specific observed precipitation data were not consistent with the NOAA Atlas 14 predicted data. This is primarily due to the NOAA Atlas 14 products being produced from analyses without including the approximately 30 NNSS precipitation gage records, several of which approach or exceed 50 year of record. Therefore, a study of precipitation frequency that incorporated the NNSS precipitation gage records into the NOAA Atlas 14 dataset, was performed specifically for the NNSS to derive more accurate site-specific precipitation data products. Precipitation frequency information, such as the depth-duration-frequency (DDF) relationships, are required to generate synthetic standard design storm hydrographs and assess actual precipitation events. In this study, the actual long-term NNSS precipitation gage records, some of which are the longest gage records in southern and central Nevada, were analyzed to allow for more accurate precipitation DDF estimates to be developed for the NNSS. Gridded maps of precipitation frequency for the NNSS and surrounding areas were then produced.

  3. [Mercury pollution investigation in predominant plants surrounding Shenzhen Qingshuihe municipal solid waste incineration plant].

    Science.gov (United States)

    Zhao, Hong-Wei; Zhong, Xiu-Ping; Liu, Yang-Sheng; Wang, Jun-Jian; Hong, Yuan; Zhao, Kang-Sai; Zeng, Hui

    2009-09-15

    In order to investigate the effects of mercury emission from municipal solid waste incineration (MSWI) on the surrounding plants and soils, the mercury concentrations were examined in the plant samples including leaves and stems and the soil samples around Shenzhen Qingshuihe MSWI Plant. Results show that, these plants are significantly polluted by mercury, the mercury concentrations of the plant leaves are 0.030 9-0.246 7 mg x kg(-1), with the mean value 0.094 8 mg x kg(-1), among the local prominent plants, the mercury concentrations in the leaves are in the order of: Acacia confuse > Litsea rotundifolia > Acacia mangium > Acacia auriculaeformis > Schima superb > Ilex asprella. The mercury concentrations of the plant stems are 0.007 4-0.119 6 mg x kg(-1), with the mean value 0.041 7 mg x kg(-1). For the same plant, the mercury concentration in its leaf correlates positively with that in its stem, but presents little correlation with that in the soil where it grows. Under the direction of the dominant wind, the concentration of smoke diffusion is often influenced by the distance from the stack and the difference of terrain. The mercury concentrations of the plant leaves and stems vary almost in accordance with spatial heterogeneity patterns of smoke diffusion. These results demonstrate that the interaction of the smoke and plant leaves play the leading role in the mercury exchange between plants and environment.

  4. Soil erosion in Slovene Istria

    Directory of Open Access Journals (Sweden)

    Matjaž Mikoš

    2009-12-01

    Full Text Available From the end of nineties of the 20th century, intense hydrologic and geomorphologic research is taking place in the Slovene Istria. As a part of this research also studies on soil erosion were undertaken in the period from 2005 to 2008. The field measurements were under taken onclosed 1m2 large erosion plots under three different land uses (on bare soils in an olive grove, on an overgrown meadow, in a forest, placed south of the Marezige village in the Rokava River basin.We show weekly measurements of surface erosion (interrill erosion for the period of 13 months (the end of March 2005 – the end of April 2006, as well as monthly and seasonal averages together with selected linear statistical correlations between soil erosion and weather parameters.From May 2005 to April 2006 the interrill erosion on bare soils in an olive grove with an inclination of 5.5° amounted to 9013 g/m2 (90 t/ha that corresponds to surface lowering rate of 8.5 mm/yr; on an overgrown meadow with an inclination of 9.4° it amounted to 168 g/m2 (1,68 t/ha that corresponds to surface lowering rate of 0.16 mm//yr; and in a forest with an inclination of 7.8° it amounted to 391 g/m2 (3,91 t/ha and in a forest with an inclination of 21.4° it amounted to 415 g/m2 (4,15 t/ha, respectively, that corresponds to surface lowering rate of 0.4 mm/yr.

  5. Soft Landing of Bare PtRu Nanoparticles for Electrochemical Reduction of Oxygen

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, Grant E.; Colby, Robert J.; Engelhard, Mark H.; Moon, DaeWon; Laskin, Julia

    2015-08-07

    Magnetron sputtering of two independent Pt and Ru targets coupled with inert gas aggregation in a modified commercial source has been combined with soft landing of mass-selected ions to prepare bare 4.5 nm diameter PtRu alloy nanoparticles on glassy carbon electrodes with controlled size and morphology for electrochemical reduction of oxygen in solution. Employing atomic force microscopy (AFM) it is shown that the nanoparticles bind randomly to the glassy carbon electrode at a relatively low coverage of 7 x 104 ions µm-2 and that their average height is centered at 4 nm. Scanning transmission electron microscopy images obtained in the high-angle annular dark field mode (STEM-HAADF) further confirm that the soft-landed PtRu alloy nanoparticles are uniform in size and have a Ru core decorated with small regions of Pt on the surface. Wide-area scans of the electrodes using X-ray photoelectron spectroscopy (XPS) reveal the presence of both Pt and Ru in relative atomic concentrations of ~9% and ~33%, respectively. Deconvolution of the high energy resolution XPS spectra in the Pt4f and Ru3d regions indicates the presence of both oxidized Pt and Ru. The substantially higher loading of Ru compared to Pt and enrichment of Pt at the surface of the alloy nanoparticles is confirmed by wide-area analysis of the electrodes using time-of-flight medium energy ion scattering (TOF-MEIS) employing both 80 keV He+ and O+ ions. The activity of electrodes containing 7 x 104 ions µm-2 of bare 4.5 nm PtRu nanoparticles toward the electrochemical reduction of oxygen was evaluated employing cyclic voltammetry (CV) in 0.1 M HClO4 and 0.5 M H2SO4 solutions. In both electrolytes a pronounced reduction peak was observed during O2 purging of the solution that was not evident during purging with Ar. Repeated electrochemical cycling of the electrodes revealed little evolution in the shape or position of the voltammograms indicating high stability of the alloy nanoparticles supported on glassy

  6. Analysis of the Temporal Response of Coupled Asymmetrical Zero-Power Subcritical Bare Metal Reactor Systems

    Energy Technology Data Exchange (ETDEWEB)

    Klain, Kimberly L. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-06-21

    The behavior of symmetrical coupled-core systems has been extensively studied, yet there is a dearth of research on asymmetrical systems due to the increased complexity of the analysis of such systems. In this research, the multipoint kinetics method is applied to asymmetrical zeropower, subcritical, bare metal reactor systems. Existing research on asymmetrical reactor systems assumes symmetry in the neutronic coupling; however, it will be shown that this cannot always be assumed. Deep subcriticality adds another layer of complexity and requires modification of the multipoint kinetics equations to account for the effect of the external neutron source. A modified set of multipoint kinetics equations is derived with this in mind. Subsequently, the Rossi-alpha equations are derived for a two-region asymmetrical reactor system. The predictive capabilities of the radiation transport code MCNP6 for neutron noise experiments are shown in a comparison to the results of a series of Rossi-alpha measurements performed by J. Mihalczo utilizing a coupled set of symmetrical bare highly-enriched uranium (HEU) cylinders. The ptrac option within MCNP6 can generate time-tagged counts in a cell (list-mode data). The list-mode data can then be processed similarly to measured data to obtain values for system parameters such as the dual prompt neutron decay constants observable in a coupled system. The results from the ptrac simulations agree well with the historical measured values. A series of case studies are conducted to study the effects of geometrical asymmetry in the coupling between two bare metal HEU cylinders. While the coupling behavior of symmetrical systems has been reported on extensively, that of asymmetrical systems remains sparse. In particular, it appears that there has been no previous research in obtaining the coupling time constants for asymmetrically-coupled systems. The difficulty in observing such systems is due in part to the inability to determine the

  7. 6.1 channel general planar surround sound system

    Institute of Scientific and Technical Information of China (English)

    XIE Bosun

    2001-01-01

    A new 6.1 channel surround sound system and its two signal mixing methods are proposed. Theoretical and experimental results show that the system is able to recreate 360°sound image in horizontal plane. Especially, compared with current 5.1 channel system, lateral and rear image of the new system is improved obviously. Therefore it is suitable to be used as a general surround sound system. It is also proved that, the new system is fully compatible with 5.1 channel system, and current methods are available to record 6.1 channel signals.

  8. Linking disadvantaged housing areas to the surrounding city

    DEFF Research Database (Denmark)

    Stender, Marie

    Several disadvantaged social housing areas in Denmark are currently undergo-ing thorough physical refurbishments, aiming to integrate them better with the surrounding city. The ambition is to attract new users and residents by opening up the borders of the area and establish attractive, new...... that especially eve-ryday-route strategies adding new public functions within the area can pave the way for integration with the surroundings. The applicability of such strategies is however highly dependent on the context, location and existing image of the ar-ea. Social distance may sustain though physical...

  9. Effects of extreme drought on agriculture soil and sustainability of different drought soil

    Directory of Open Access Journals (Sweden)

    S. M. Geng

    2014-01-01

    Full Text Available Content of microbial biomass carbon was selected as indicator for identifying effects of extreme drought on agriculture soil ecosystem. Through a series of prototype observation experiments, changing tendencies of microbial biomass carbon content and the proportion of microbial biomass carbon in soil organic carbon were identified. The optimum mass water content of soil for microbial biomass carbon was 19.5% and the demarcation point of microbial biomass carbon to drought was 14.3%, which could be used to demonstrate alters and degradation of soil ecosystem as well as the irrigation requirement of crops. We evaluated sustainability of different drought soil ecosystems after experiencing rainstorm with rehabilitation. The results suggested that soil ecosystem which was interfered by moderate drought could recover and its tolerance to drought was improved, as well as its function and activity. Soil ecosystem could barely recover from severe drought and could not adapt to severe drought stress. Soil ecosystem could not restore from extreme drought within a few days, the function and structure were damaged. We came to the conclusion that mass water content of soil should kept above 10% to avoid destroying function and structure while soil ecosystem would better be watered when mass water content was lower than 14.3% in order to maintain high productivity.

  10. EFFECT OF SOIL SOLARIZATION ON THERMAL REGIME OF PLASTIC GREENHOUSE SOIL

    OpenAIRE

    Nereu Augusto Streck; Flavio Miguel Schneider; Galileo Adeli Buriol

    1994-01-01

    SUMMARY Temperature modification in soil of plastic greenhouse caused by solarization was measured during the summer in the Subtropical Central Region of the Rio Grande do Sul State, Brazil. The experiment was carried out in a 10m x 25m greenhouse covered with low density transparent polyethylene (PE). Four 6m x 4m plots were mulched with 100µm thickness PE sheets, from December 12, 1992 to March 7, 1993. Four other plots (same size) without the cover were used as control (bare soil). Results...

  11. Soils - NRCS Web Soil Survey

    Data.gov (United States)

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

  12. Root-associated fungal communities in three Pyroleae species and their mycobiont sharing with surrounding trees in subalpine coniferous forests on Mount Fuji, Japan.

    Science.gov (United States)

    Jia, Shuzheng; Nakano, Takashi; Hattori, Masahira; Nara, Kazuhide

    2017-07-13

    Pyroleae species are perennial understory shrubs, many of which are partial mycoheterotrophs. Most fungi colonizing Pyroleae roots are ectomycorrhizal (ECM) and share common mycobionts with their Pyroleae hosts. However, such mycobiont sharing has neither been examined in depth before nor has the interspecific variation in sharing among Pyroleae species. Here, we examined root-associated fungal communities in three co-existing Pyroleae species, including Pyrola alpina, Pyrola incarnata, and Orthilia secunda, with reference to co-existing ECM fungi on the surrounding trees in the same soil blocks in subalpine coniferous forests. We identified 42, 75, and 18 fungal molecular operational taxonomic units in P. alpina, P. incarnata, and O. secunda roots, respectively. Mycobiont sharing with surrounding trees, which was defined as the occurrence of the same mycobiont between Pyroleae and surrounding trees in each soil block, was most frequent among P. incarnata (31 of 44 plants). In P. alpina, sharing was confirmed in 12 of 37 plants, and the fungal community was similar to that of P. incarnata. Mycobiont sharing was least common in O. secunda, found in only 5 of 32 plants. Root-associated fungi of O. secunda were dominated by Wilcoxina species, which were absent from the surrounding ECM roots in the same soil blocks. These results indicate that mycobiont sharing with surrounding trees does not equally occur among Pyroleae plants, some of which may develop independent mycorrhizal associations with ECM fungi, as suggested in O. secunda at our research sites.

  13. [Spacial variation and eco-environmental risk of heavy metals in soil surrounding Guanting Reservoir].

    Science.gov (United States)

    Wang, Tie-Yu; Luo, Wei; Lü, Yong-Long; Shi, Ya-Juan; Wang, Xiao-Long

    2007-02-01

    Topsoil samples around the Guanting Reservoir ranging from 2 - 10km were measured for heavy metals concentrations. GIS and geostatistical techniques were applied to analyze the special variation and eco-environmental risk of heavy metals. The results show that Cd is the major contamination in this area, 3.4 fold higher than the national background level, with a mean of 0.68 mg/kg and a standard deviation of 0.17. The area in which Cd concentration is higher than the second level of national standard accounts for about 40% of the whole study area. Spacial variation of heavy metals (except Ni) mainly is induced by the stochastic factors-mostly anthropogenic activities, e.g. fertilizer application, cultivation and planting modes, etc. The spatial pattern of heavy metals approximately declines in the W-N and N-S direction, with the highest value in the region between Yanghe River and Huailai County. The complex contamination index of heavy metals has the same distribution as their concentrations. However, the complex eco-risk index with higher value mainly occurs in vicinities of Huailai County, Yanqing County and Beixinpu town. It suggests that the town with higher population density and industrialization will induce both environmental pollution and ecological risk.

  14. Factors Influencing the Spatial Distribution of Organochlorine Pesticides in Soils surrounding Chemical Industrial Parks

    NARCIS (Netherlands)

    Wang, G.; Lu, Y.L.; Wang, T.Y.; Zhang, X.; Han, J.Y.; Luo, W.; Shi, Y.J.; Li, J.; Jiao, W.T.

    2009-01-01

    Topsoil samples (n = 105) were collected to Study the distribution of dichlorodiphenyltrichloroethane (DDT) and hexachlorocyclohexane (HCH) residues in the vicinity of chemical industrial parks in Tianjin, China. The occurrence and distribution of target organochlorine pesticides (OCPs) were mapped

  15. Factors Influencing the Spatial Distribution of Organochlorine Pesticides in Soils surrounding Chemical Industrial Parks

    NARCIS (Netherlands)

    Wang, G.; Lu, Y.L.; Wang, T.Y.; Zhang, X.; Han, J.Y.; Luo, W.; Shi, Y.J.; Li, J.; Jiao, W.T.

    2009-01-01

    Topsoil samples (n = 105) were collected to Study the distribution of dichlorodiphenyltrichloroethane (DDT) and hexachlorocyclohexane (HCH) residues in the vicinity of chemical industrial parks in Tianjin, China. The occurrence and distribution of target organochlorine pesticides (OCPs) were mapped

  16. Assessment of some heavy metals in the surrounding soils of an ...

    African Journals Online (AJOL)

    OYELEKE PETER

    Vol. 10(1), pp. 1-8, January, 2016 ... 1Department of Science Laboratory Technology, Federal College of Animal Health and Production Technology, Moor .... maintained at 100°C and allowed to boil for 2 h with intermittently ... and pharmaceutical industrial sites in Suleja and Minna, ..... Heavy Metal Concentrations in Top.

  17. Temperature sensitivity of soil organic matter decomposition was strongly affected by land use under low temperature

    Science.gov (United States)

    Zang, Huadong; Blagodatskaya, Evgenia; Xu, Xingliang; Kuzyakov, Yakov

    2017-04-01

    The temperature sensitivity of soil organic matter (SOM) decomposition (often measured as Q10 value) is important for predicting global carbon (C) stocks under warming scenarios. However, the effects of land use and labile substrates on Q10 value remain unclear. We investigated CO2 emission from soils of three land use types (i.e. grassland, cropland and bare fallow) at five temperatures (0, 10, 20, 30 and 40 °C) with or without labile C (14C-glucose) addition. The CO2 efflux from SOM increased with temperature and was 43, 21 and 9 times higher at 40 °C than at 0 °C in grassland, cropland and bare fallow soils, respectively. High temperature strongly increased the cumulative priming effect (PE) in grassland soil (from 0.1 to 4.7 mg g-1 SOC), while the PE in cropland and bare fallow was not sensitive to warming. The Q10 of SOM (2.3-6) was higher at low temperature (0-10 °C) and decreased strongly to Q10 = 1.7-2.0 with temperature increase. The Q10 of SOM in grassland was 1.6 and 2.7 times higher than cropland and bare fallow at low temperature, respectively. Labile C addition decreased the Q10 of SOM in grassland and cropland, but increased it in bare fallow, especially under low temperature. Overall, temperature sensitivity of SOM was strongly affected by land use at low temperature and was relatively stable in high temperature (> 10°C). Labile C addition mainly affected temperature sensitivity of SOM at lower temperature, which decreased in grassland and cropland, and increased in bare fallow. These findings indicate that global warming may result in regionally variable responses in soil respiration, with colder climates being considerably more responsive to increased ambient temperatures.

  18. Responses of soil microbial respiration to plantations depend on soil properties in subtropical China

    Institute of Scientific and Technical Information of China (English)

    ZHANG Yan-jie; YAN Yue; FU Xiang-ping; YANG Jie; ZHANG Su-yan; XU Shan; TANG Zheng; LI Zhong-fang; LU Shun-bao

    2016-01-01

    Assessing the impact of plantation on microbial respiration (MR) is vitaly important to understand the interactions between belowground metabolism and land use change. In this study, cumulative MR was determined by alkali absorption method in 1, 3, 7, 14, 21, 28, 35, 42, 49, and 56 days from the soil in a representative plantations in the subtropical region of China. The treatment of plantations contained no plant (CK), orange trees (Citrus reticulata)+Bahia grass (Paspalum notatum) (GB), orange trees (C. reticulata)+Bahia grass (P.notatum)+soybean (Giycine max(L.)Merril) (GBH). Results showed that plantation had signiifcant effects on microbial respiration and the responses of microbial respiration to plantation from different soil layers and topographies were different: in 0–20 cm in uphil: GB>GBH>CK; in 20–40 cm in uphil: GBH>CK>GB; in 0–20 cm in downhil: GBH>CK>GB; in 20–40 cm in downhil: GB>CK>GBH. Furthermore, plantation also altered the relationships between MR and soil properties. In CK, microbial respiration was positively correlated with NH4+ and soil total N, and negatively correlated with soil moisture, pH, NO3–, and microbial biomass carbon (MBC). In GB, microbial respira-tion under GB signiifcantly negatively correlated with dissolved organic carbon (DOC). In GBH, microbial respiration under GBH was positively correlated with NH4+, MBC, total soil carbon (TC), and total soil nitrogen (TN), and negatively correlated with soil moisture (SM), pH, NO3–, and DOC. The underlying mechanisms could be attributed to soil heterogeneity and the effects of plantation on soil properties. Our results also showed that plantation signiifcantly increased soil C storage, which suggested plantation is a key measure to enhance soil C sequestration and mitigate global CO2 emission, especialy for the soil with low initial soil carbon content or bared soil.

  19. Heterogeneity of soil surface temperature induced by xerophytic shrub in a revegetated desert ecosystem, northwestern China

    Indian Academy of Sciences (India)

    Ya-Feng Zhang; Xin-Ping Wang; Yan-Xia PAN; Rui Hu; Hao Zhang

    2013-06-01

    Variation characteristics of the soil surface temperature induced by shrub canopy greatly affects the nearsurface biological and biochemical processes in desert ecosystems. However, information regarding the effects of shrub upon the heterogeneity of soil surface temperature is scarce. Here we aimed to characterize the effects of shrub (Caragana korshinskii) canopy on the soil surface temperature heterogeneity at areas under shrub canopy and the neighbouring bare ground. Diurnal variations of soil surface temperature were measured at areas adjacent to the shrub base (ASB), beneath the midcanopy (BMC), and in the bare intershrub spaces (BIS) at the eastern, southern, western and northern aspects of shrub, respectively. Results indicated that diurnal mean soil surface temperature under the C. korshinskii canopy (ASB and BMC) was significantly lower than in the BIS, with the highest in the BIS, followed by the BMC and ASB. The diurnal maximum and diurnal variations of soil surface temperatures under canopy vary strongly with different aspects of shrub with the diurnal variation in solar altitude, which could be used as cues to detect safe sites for under-canopy biota. A significant empirical linear relationship was found between soil surface temperature and solar altitude, suggesting an empirical predicator that solar altitude can serve for soil surface temperature. Lower soil surface temperatures under the canopy than in the bare intershrub spaces imply that shrubs canopy play a role of ‘cool islands’ in the daytime in terms of soil surface temperature during hot summer months in the desert ecosystems characterized by a mosaic of sparse vegetation and bare ground.

  20. Bremsstrahlung from relativistic bare heavy ions: Nuclear and electronic contributions in amorphous and crystalline materials

    DEFF Research Database (Denmark)

    Jensen, Tue Vissing; Sørensen, Allan Hvidkjær

    2013-01-01

    A charged particle emits bremsstrahlung while traversing matter. We calculate the radiation cross section for bare heavy ions penetrating amorphous materials and single crystals at highly relativistic energies. The main component originates in scattering of the virtual photons of screened target...... at a very low value. Incoherent interaction with single target electrons gives rise to two additional bremsstrahlung components, a modest component due to scattering of virtual photons of the electrons on the projectile and a strong low-energy component due to scattering of the virtual photons...... of the projectile on the electrons. The difference in radiation levels can be traced to the mass of the scatterer. Since target electrons are more widely distributed than nuclei in a crystal channel the variation of the electron component of the bremsstrahlung with incidence angle to a major crystallographic...

  1. Self-Assembly of Graphene Nanoblisters Sealed to a Bare Metal Surface.

    Science.gov (United States)

    Larciprete, Rosanna; Colonna, Stefano; Ronci, Fabio; Flammini, Roberto; Lacovig, Paolo; Apostol, Nicoleta; Politano, Antonio; Feulner, Peter; Menzel, Dietrich; Lizzit, Silvano

    2016-03-09

    The possibility to intercalate noble gas atoms below epitaxial graphene monolayers coupled with the instability at high temperature of graphene on the surface of certain metals has been exploited to produce Ar-filled graphene nanosized blisters evenly distributed on the bare Ni(111) surface. We have followed in real time the self-assembling of the nanoblisters during the thermal annealing of the Gr/Ni(111) interface loaded with Ar and characterized their morphology and structure at the atomic scale. The nanoblisters contain Ar aggregates compressed at high pressure arranged below the graphene monolayer skin that is decoupled from the Ni substrate and sealed only at the periphery through stable C-Ni bonds. Their in-plane truncated triangular shapes are driven by the crystallographic directions of the Ni surface. The nonuniform strain revealed along the blister profile is explained by the inhomogeneous expansion of the flexible graphene lattice that adjusts to envelop the Ar atom stacks.

  2. Radiative recombination of twisted electrons with bare nuclei: going beyond the Born approximation

    CERN Document Server

    Zaytsev, V A; Shabaev, V M

    2016-01-01

    We present a fully relativistic investigation of the radiative recombination of a twisted electron with a bare heavy nucleus. The twisted electron is described by the wave function which accounts for the interaction with the nucleus in all orders in $\\alpha Z$. We use this wave function to derive the probability of the radiative recombination with a single ion being shifted from the twisted electron propagation direction. We also consider more realistic experimental scenarios where the target is either localized (mesoscopic) or infinitely wide (macroscopic). The situation when the incident electron is a coherent superposition of two vortex states is considered as well. For the nonrelativistic case we present analytical expressions which support our numerical calculations. We study in details the influence of the electron twistedness on the polarization and angular distribution of the emitted photon. It is found that these properties of the outgoing photon might be very sensitive to the total angular momentum ...

  3. The Integrity bare-metal stent made by continuous sinusoid technology.

    Science.gov (United States)

    Turco, Mark A

    2011-05-01

    The Integrity Coronary Stent System (Medtronic Vascular, CA, USA) is a low-profile, open-cell, cobalt-chromium-alloy advanced bare-metal iteration of the well-known Driver/Micro-Driver Coronary Stent System (Medtronic Vascular). The Integrity stent is made with a process called continuous sinusoid technology. This process allows stent construction via wrapping a single thin strand of wire around a mandrel in a sinusoid configuration, with laser fusion of adjacent crowns. The wire-forming process and fusion pattern provide the stent with a continuous preferential bending plane, intended to allow easier access to, and smoother tracking within, distal and tortuous vessels while radial strength is maintained. Continuous sinusoid technology represents innovation in the design of stent platforms and will provide a future stent platform for newer technology, including drug-eluting stent platforms, drug-filled stents and core wire stents.

  4. Comparison of Bare metal Vs Drug eluting stents for in-stent Restenosis among Diabetics

    Directory of Open Access Journals (Sweden)

    Kakhaber Etsadashvili

    2011-06-01

    Full Text Available Background: Diabetes mellitus is associated with an increased risk of restenosis, stent thrombosis, and death afterpercutaneous coronary interventions. Little is known about the late outcome of patients with diabetes mellitus whoreceive drug-eluting stents (DES or bare metal stents (BMS.Methods: From January 2008 to January 2010, six patients with DES and 20 with BMS, ISR were identified at ourinstitution.Results: The median age of our diabetic cohort was 63 years, and 87 of the patients were male. For two years, ratesof repeat target-vessel revascularization were significantly lower among diabetic patients treated with DEScompared with those treated with BMS (5.8% vs. 17.0%, p=0.003.Conclusions: DES is effective among diabetic patients in substantially reducing the need for repeat TVR.

  5. Highly nonlinear optical regime in graphene-assisted cavities: lasing threshold bares graphene nonlinearity

    CERN Document Server

    Ciattoni, Alessandro

    2014-01-01

    Strong nonlinear optical mechanisms operating in a miniaturized environment have a key role in photonics since they allow complex and versatile light manipulation within subwavelength devices. On the other hand, due to its two-dimensional planar geometry, graphene can easily be embedded within miniaturized structures and has fascinating linear and nonlinear optical properties arising from its relativistic electron dynamics. However, very few light steering graphene-based setups with a strong nonlinear behavior have been proposed since, due to its intrinsic planar localization, graphene nonlinearity has to be exploited through novel schemes not available in standard bulk nonlinear optics. Here we show that an active cavity hosting a graphene sheet, when tuned near its lasing threshold, is able to isolate the spatially localized graphene nonlinearity thus producing a very strong nonlinear device response with multi-valued features. The proposed strategy for exploiting graphene nonlinearity through its baring co...

  6. Electron-positron pair creation in low-energy collisions of heavy bare nuclei

    CERN Document Server

    Maltsev, I A; Tupitsyn, I I; Bondarev, A I; Kozhedub, Y S; Plunien, G; Stoehlker, Th

    2014-01-01

    A new method for calculations of electron-positron pair-creation probabilities in low-energy heavy-ion collisions is developed. The approach is based on the propagation of all one-electron states via the numerical solving of the time-dependent Dirac equation in the monopole approximation. The electron wave functions are represented as finite sums of basis functions constructed from B-splines using the dual-kinetic-balance technique. The calculations of the created particle numbers and the positron energy spectra are performed for the collisions of bare nuclei at the energies near the Coulomb barrier with the Rutherford trajectory and for different values of the nuclear charge and the impact parameter. To examine the role of the spontaneous pair creation the collisions with a modified velocity and with a time delay are also considered. The obtained results are compared with the previous calculations and the possibility of observation of the spontaneous pair creation is discussed.

  7. Intravascular ultrasound assessment of very late bare-metal stent thrombosis: a case report

    Institute of Scientific and Technical Information of China (English)

    Ji Hyun Lee; Kyung Min Kim; Jun Won Lee; Sung Gyun Ahn; Young Jin Youn

    2012-01-01

    Very late stent thrombosis (VLST) is increasingly being regarded as a complication of drug-eluting stents (DES),and delayed endothelization,local hypersensitivity reactions,and late stent malapposition due to excessive positive remodeling have been postulated as mechanisms.Considering that stent endothelialization seems to be completed within 4 weeks following bare-metal stent (BMS) placement and that BMS do not possess antiproliferative coating,the mechanism of VLST may differ between patients with DES and those with BMS.We report a case of VLST 9 years after BMS implantation,in which thrombus from the ruptured neointima was confirmed by intravascular ultrasound.This finding suggests that de novo plaque rupture at the neointimal layer within the stent may be one of the explanations for VLST.

  8. Atomistic electrodynamics simulations of bare and ligand-coated nanoparticles in the quantum size regime.

    Science.gov (United States)

    Chen, Xing; Moore, Justin E; Zekarias, Meserret; Jensen, Lasse

    2015-11-10

    The optical properties of metallic nanoparticles with nanometre dimensions exhibit features that cannot be described by classical electrodynamics. In this quantum size regime, the near-field properties are significantly modified and depend strongly on the geometric arrangements. However, simulating realistically sized systems while retaining the atomistic description remains computationally intractable for fully quantum mechanical approaches. Here we introduce an atomistic electrodynamics model where the traditional description of nanoparticles in terms of a macroscopic homogenous dielectric constant is replaced by an atomic representation with dielectric properties that depend on the local chemical environment. This model provides a unified description of bare and ligand-coated nanoparticles, as well as strongly interacting nanoparticle dimer systems. The non-local screening owing to an inhomogeneous ligand layer is shown to drastically modify the near-field properties. This will be important to consider in optimization of plasmonic nanostructures for near-field spectroscopy and sensing applications.

  9. A rare-earth-magnet ion trap for confining low-Z, bare nuclei

    Science.gov (United States)

    Brewer, Samuel M.; Tan, Joseph N.

    2009-05-01

    Simplifications in the theory for Rydberg states of hydrogenlike ions allow a substantial improvement in the accuracy of predicted levels, which can yield information on the values of fundamental constants and test theory if they can be compared with precision frequency measurements.[1] We consider the trapping of bare nuclei (fully-stripped) to be used in making Rydberg states of one-electron ions with atomic number 1earth permanent magnets, and to model the capture of charge-state-selected ions extracted from an electron beam ion trap (EBIT). An experimental apparatus adapted to the NIST EBIT will also be discussed. Reference: [1] U.D. Jentschura, P.J. Mohr, J.N. Tan, and B.J. Wundt, ``Fundamental constants and tests of theory in Rydberg states of hydrogenlike ions,'' Phys. Rev. Lett. 100, 160404 (2008).

  10. Non-destructive testing of barely visible impact damage in polymer matrix composites

    Institute of Scientific and Technical Information of China (English)

    ZHANG Z Y; M. O. W. Richardson

    2004-01-01

    Barely visible impact damage (BVID) is developed when polymer matrix composites are subjected to impact loading. The damage has an adverse effect on structural integrity, and potentially leads to catastrophic failure.Thus it is important to employ a variety of advanced non-destructive testing (NDT) techniques in parallel to unambiguously determine the integrity of composite systems. This study deals with damage evaluation using visual inspection, ultrasonic C-scan, electronic speckle pattern interferometry (ESPI), electronic shearography (ES) and optical deformation and strain measurement system (ODSMS). Internal damage was introduced using an instrumented falling weight impact test (IFWIT) machine by controlling the combination of striker mass and releasing height. It was found that different NDT techniques were successfully employed to identify and visualise the impact induced internal damage. Experimental results generated from these techniques show a good agreement in damage identification and determination. The features, capabilities and limitations associated with these techniques were briefly discussed.

  11. Fabrication and characterization of bare Ge-Sb-Se chalcogenide glass fiber taper

    Science.gov (United States)

    Luo, Baohua; Wang, Yingying; Sun, Ya'nan; Dai, Shixun; Yang, Peilong; Zhang, Peiqing; Wang, Xunsi; Chen, Feifei; Wang, Rongping

    2017-01-01

    In this work, Ge15Sb20Se65 bare glass fiber with a diameter of 500 μm was fabricated, and then tapered with different tapering parameters. The analysis of Raman and energy dispersive X-ray spectra (EDS) indicated that, a slight change in the chemical composition of the glass, fiber and tapering fiber has negligible effect on the glass structure. It was found that, the waist diameter decreases exponentially with increasing tapering length and speed, and high quality taper fiber with the cone diameter of 2.65 μm can be achieved under the optimal tapering conditions. Finally, the simulated and experimental results of the output transmission under different waist length and taper ratio show that the transmission decreases with increasing waist length and taper ratio.

  12. Cytotoxicity testing of bare CdSe quantum dots and their encapsulated structure

    Science.gov (United States)

    Kumari, Asha; Singh, Ragini Raj

    2017-07-01

    In this work we have synthesized CdSe quantum dots (QDs) and their polymer encapsulated structures by wet chemical method for cytotoxicity testing. These QDs were synthesized by using aqueous solvent to make them hydrophilic because we want to use these for bioimaging purpose. The cytotoxicity is major concern to use these quantum dots in bio application because these are made up of heavy metal ions so to make these QDs nontoxic and to improve their optical properties we encapsulated these QDs by polymers. Thereafter we have studied the cytotoxicity of CdSe QDs and their polymer encapsulated structure.MTT method (3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide method) was used to study toxicity of QDs toward MDCK epithelial cell line. Effect of encapsulation on optical properties was analyzed by Photoluminescence spectroscopy. QDs encapsulated with polymer possess improved optical properties with greater fluorescence intensity and lesser cytotoxicity as compare to bare CdSe.

  13. Nanosecond electrical explosion of bare and dielectric coated tungsten wire in vacuum

    Science.gov (United States)

    Wang, Kun

    2017-02-01

    Experiments of the electrical explosion of tungsten wire with and without insulating coatings demonstrate that the insulating coatings exert a significant influence on the exploding characteristics. The shadowgraphy and interferometry diagnostics are applied to present the morphology of the exploding products. In the experiments, energy of ˜3.2 eV/atom is deposited into the bare tungsten wire at the instant of voltage breakdown, giving a velocity of 0.38 km/s for the high density core. The value and structure of the energy deposition for the tungsten wire explosions are substantially improved by employing the thin dielectric coatings. Energy of ˜15.2 eV/atom is deposited into the coated tungsten wire transforming the wire into gaseous state and the expanding velocity of the high density core is 5.64 km/s. The interference phase shift and atomic density are reconstructed from the interferogram for the exploding coated tungsten wire.

  14. Moss cushions facilitate water and nutrient supply for plant species on bare limestone pavements

    DEFF Research Database (Denmark)

    Jensen, Kaj Sand; Hammer, Kathrine

    2012-01-01

    Dense moss cushions of different size are distributed across the bare limestone pavements on Øland, SE Sweden. Increasing cushion size is predicted to physically protect and improve performance and colonization by vascular plants. Therefore, we tested water balance, phosphorus supply, and species...... richness, and evaluated duration of plant activity during desiccation as a function of ground area, for a large collection of moss cushions. We found that lower evaporation and higher water storage contributed equally to extending the desiccation period with increasing cushion size. Evaporation rates...... under stagnant conditions. One moss species was added to the species pool for every nine-fold increase in cushion area. Vascular plants were absent from the smallest cushions, whereas one or two species, on average, appeared in 375- and 8,500-cm(2) cushions with water available for 6 and 10 days during...

  15. Reliability Optimization of Radial Distribution Systems Employing Differential Evolution and Bare Bones Particle Swarm Optimization

    Science.gov (United States)

    Kela, K. B.; Arya, L. D.

    2014-09-01

    This paper describes a methodology for determination of optimum failure rate and repair time for each section of a radial distribution system. An objective function in terms of reliability indices and their target values is selected. These indices depend mainly on failure rate and repair time of a section present in a distribution network. A cost is associated with the modification of failure rate and repair time. Hence the objective function is optimized subject to failure rate and repair time of each section of the distribution network considering the total budget allocated to achieve the task. The problem has been solved using differential evolution and bare bones particle swarm optimization. The algorithm has been implemented on a sample radial distribution system.

  16. Vertical and horizontal soil CO2 transport and its exchanges with the atmosphere

    Science.gov (United States)

    Sánchez-Cañete, Enrique P.; Serrano-Ortíz, Penélope; Kowalski, Andrew S.; Curiel Yuste, Jorge; Domingo, Francisco; Oyonarte, Cecilio

    2015-04-01

    The CO2 efflux from soils to the atmosphere constitutes one of the major fluxes of the terrestrial carbon cycle and is a key determinant for sources and sinks of CO2 in land-atmosphere exchanges. Because of their large global magnitude, even small changes in soil CO2 effluxes directly affect the atmospheric CO2 content. Despite much research, models of soil CO2 efflux rates are highly uncertain, with the positive or negative feedbacks between underground carbon pools and fluxes and their temperature sensitivities in future climate scenarios largely unknown. Now it is necessary to change the point of view regarding CO2 exchange studies from an inappropriately conceived static system in which all respired CO2 is directly emitted by molecular processes to the atmosphere, to a dynamic system with gas transport by three different processes: convection, advection and molecular diffusion. Here we study the effects of wind-induced advection on the soil CO2 molar fraction during two years in a shrubland plateau situated in the Southeast of Spain. A borehole and two subterranean profiles (vertical and horizontal) were installed to study CO2 transport in the soil. Exchanges with the atmosphere were measured by an eddy covariance tower. In the vertical profile, two CO2 sensors (GMP-343, Vaisala) were installed at 0.15m and 1.5m along with soil temperature and humidity probes. The horizontal profile was designed to measure horizontal movements in the soil CO2 molar fraction due to down-gradient CO2 from the plant, where the majority CO2 is produced, towards bare soil. Three CO2 sensors (GMM-222, Vaisala) were installed, the first below plant (under-plant), the second in bare soil separated 25 cm from the first sensor (near-plant) and the third in bare soil at 25 cm from the second sensor (bare soil). The results show how the wind induces the movement of subterranean air masses both horizontally and vertically, affecting atmospheric CO2 exchanges. The eddy covariance tower

  17. Spectral Analysis Related to Bare-Metal and Drug-Eluting Coronary Stent Implantation

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Rose Mary Ferreira Lisboa da, E-mail: roselisboa@cardiol.br [Faculdade de Medicina da UFMG, Divinópolis, MG (Brazil); Silva, Carlos Augusto Bueno [Faculdade de Medicina da UFMG, Divinópolis, MG (Brazil); Belo Horizonte, Hospital São João de Deus, Divinópolis, MG (Brazil); Greco, Otaviano José [Belo Horizonte, Hospital São João de Deus, Divinópolis, MG (Brazil); Moreira, Maria da Consolação Vieira [Faculdade de Medicina da UFMG, Divinópolis, MG (Brazil)

    2014-08-15

    The autonomic nervous system plays a central role in cardiovascular regulation; sympathetic activation occurs during myocardial ischemia. To assess the spectral analysis of heart rate variability during stent implantation, comparing the types of stent. This study assessed 61 patients (mean age, 64.0 years; 35 men) with ischemic heart disease and indication for stenting. Stent implantation was performed under Holter monitoring to record the spectral analysis of heart rate variability (Fourier transform), measuring the low-frequency (LF) and high-frequency (HF) components, and the LF/HF ratio before and during the procedure. Bare-metal stent was implanted in 34 patients, while the others received drug-eluting stents. The right coronary artery was approached in 21 patients, the left anterior descending, in 28, and the circumflex, in 9. As compared with the pre-stenting period, all patients showed an increase in LF and HF during stent implantation (658 versus 185 ms2, p = 0.00; 322 versus 121, p = 0.00, respectively), with no change in LF/HF. During stent implantation, LF was 864 ms2 in patients with bare-metal stents, and 398 ms2 in those with drug-eluting stents (p = 0.00). The spectral analysis of heart rate variability showed no association with diabetes mellitus, family history, clinical presentation, beta-blockers, age, and vessel or its segment. Stent implantation resulted in concomitant sympathetic and vagal activations. Diabetes mellitus, use of beta-blockers, and the vessel approached showed no influence on the spectral analysis of heart rate variability. Sympathetic activation was lower during the implantation of drug-eluting stents.

  18. Microtopography of bare peat: an objective classification from high-resolution topographic survey data

    Science.gov (United States)

    Smith, Mark; Warburton, Jeff

    2017-04-01

    Peatlands globally are at risk of degradation through increased susceptibility to erosion as a result of climate change. For peatland restoration practices to be designed efficiently and evaluated effectively, quantification of eroded peat volumes is required alongside an understanding of the processes responsible for their degradation. Owing to the unique material properties of peat, fine-scale microtopographic expressions of surface processes are especially pronounced and present a potentially rich source of geomorphological information; providing valuable insights into the stability and dominant surface process regimes. Bare peat is highly responsive to changing environmental forces acting at the near surface and characteristic microtopographies emerge in response to rainfall, surface wash, wind action and fluctuations in surface temperature (both drying and freezing). Spatial and temporal variations in surface roughness reflect contrasts in the physical properties of the peat and key erosion processes acting in combination. We present the first conceptual framework to rigorously describe bare peat microtopography and use Structure-from-Motion (SfM) surveys to quantify roughness for different peat surfaces. Through application of a survey-grade structured-light hand-held 3D imager (Mantis Vision F5-Short Range) which can represent sub-millimetre topographic variability in field conditions, we present the most reliable field validation of SfM at the plot scale (classification system derived from decision tree analysis. After training on 66% of the data, the decision tree correctly classified 85% of plots into microtopographic types using 5 roughness metrics each of which quantified a different aspect of the surface variability. We show that through a combination of roughness metrics, microtopographic types can be identified objectively from high resolution survey data, aiding the interpretation of sediment budgets and providing a much-needed geomorphological

  19. Spectral Analysis Related to Bare-Metal and Drug-Eluting Coronary Stent Implantation

    Directory of Open Access Journals (Sweden)

    Rose Mary Ferreira Lisboa da Silva

    2014-08-01

    Full Text Available Background: The autonomic nervous system plays a central role in cardiovascular regulation; sympathetic activation occurs during myocardial ischemia. Objective: To assess the spectral analysis of heart rate variability during stent implantation, comparing the types of stent. Methods: This study assessed 61 patients (mean age, 64.0 years; 35 men with ischemic heart disease and indication for stenting. Stent implantation was performed under Holter monitoring to record the spectral analysis of heart rate variability (Fourier transform, measuring the low-frequency (LF and high-frequency (HF components, and the LF/HF ratio before and during the procedure. Results: Bare-metal stent was implanted in 34 patients, while the others received drug-eluting stents. The right coronary artery was approached in 21 patients, the left anterior descending, in 28, and the circumflex, in 9. As compared with the pre-stenting period, all patients showed an increase in LF and HF during stent implantation (658 versus 185 ms2, p = 0.00; 322 versus 121, p = 0.00, respectively, with no change in LF/HF. During stent implantation, LF was 864 ms2 in patients with bare-metal stents, and 398 ms2 in those with drug-eluting stents (p = 0.00. The spectral analysis of heart rate variability showed no association with diabetes mellitus, family history, clinical presentation, beta-blockers, age, and vessel or its segment. Conclusions: Stent implantation resulted in concomitant sympathetic and vagal activations. Diabetes mellitus, use of beta-blockers, and the vessel approached showed no influence on the spectral analysis of heart rate variability. Sympathetic activation was lower during the implantation of drug-eluting stents.

  20. Ecological mechanisms linking protected areas to surrounding lands.

    Science.gov (United States)

    Hansen, Andrew J; DeFries, Ruth

    2007-06-01

    Land use is expanding and intensifying in the unprotected lands surrounding many of the world's protected areas. The influence of this land use change on ecological processes is poorly understood. The goal of this paper is to draw on ecological theory to provide a synthetic framework for understanding how land use change around protected areas may alter ecological processes and biodiversity within protected areas and to provide a basis for identifying scientifically based management alternatives. We first present a conceptual model of protected areas embedded within larger ecosystems that often include surrounding human land use. Drawing on case studies in this Invited Feature, we then explore a comprehensive set of ecological mechanisms by which land use on surrounding lands may influence ecological processes and biodiversity within reserves. These mechanisms involve changes in ecosystem size, with implications for minimum dynamic area, species-area effect, and trophic structure; altered flows of materials and disturbances into and out of reserves; effects on crucial habitats for seasonal and migration movements and population source/sink dynamics; and exposure to humans through hunting, poaching, exotics species, and disease. These ecological mechanisms provide a basis for assessing the vulnerability of protected areas to land use. They also suggest criteria for designing regional management to sustain protected areas in the context of surrounding human land use. These design criteria include maximizing the area of functional habitats, identifying and maintaining ecological process zones, maintaining key migration and source habitats, and managing human proximity and edge effects.