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1

Soil Horizons  

NSDL National Science Digital Library

This activity involves previously collected soils from each horizon of a soil profile. The bags from one soil profile are given to a group and the students put the bags in the proper order. This involves student groups looking at each other's sample bags as well as their own and sharing information. After some discussion, during which the instructor makes certain that the students have gotten the soil samples into their correct horizon sequence, the bags are opened and examined to let the students see the different textures and properties of each horizon. Students will discover that each soil is different due to different bedrock and weathering conditions. Some soils may not show all of the above horizons, while other soils may clearly show the development of each layer. The thickness of the individual layers may vary greatly also.

2

Direct estimates of pedogenic magnetite as a tool to reconstruct past climates from buried soils  

Microsoft Academic Search

Variations in magnetic properties of buried soils can be used to reconstruct past climatic conditions during paleosol formation. Most methods, however, are based on comparisons between the magnetically enriched upper soil horizons and the magnetically unaltered parent material. In thin loess-paleosol sequences such a comparison can be problematic because all horizons, soil and underlying loess, may be affected to varying

Christoph E. Geiss; Ramon Egli; C. William Zanner

2008-01-01

3

Buried soils of Late Quaternary moraines of the Wind River Mountains, Wyoming  

SciTech Connect

Buried soils occur on kettle floors of four Pinedale moraine catenas of the western Wind River Mountains of Wyoming. Radiocarbon ages from bulk samples of Ab horizons indicate the soils were buried during the mid-Holocene. Soils on kettle floors have silty A and Bw horizons that overlie buried A and B horizons that also formed in silt-rich sediments. Crests and backslope soils also have A and Bw horizons of sandy loam formed over 2BCb and 2Cb horizons of stony coarse loamy sand. Recent data show the silty textures of the A and B horizons are due to eolian silt and clay from the Green River Basin just west of the mountains. The buried soils appear to represent alternate periods of erosion and deposition on the moraines during the Holocene. The original soils developed on higher slopes of the moraines were eroded during the mid-Holocene and the 2BC and 2C horizons exposed at the surface. Eroded soil sediments were transported downslope onto the kettle floors. Following erosion, silt-rich eolian sediments accumulated on all surfaces and mixed with the BC and C horizons (the mixed loess of Shroba and Birkeland). The present surface soils developed within this silt-rich material. Stone lines often occur at the Bw-2BCb/2Cb boundary, and mark the depth to which the earlier soils were eroded. Thus, soil profiles at the four localities result from two periods of soil formation, interrupted by an interval of erosion during the mid-Holocene. Moraines of this study are adjacent to the Fremont Lake type area for the Pinedale glaciation of the Rocky Mountains. Buried soils in kettles of the moraines indicates the soil characteristics of the Pinedale type region are not necessarily due to continuous post-Pinedale development, but may result from more than one episode of soil formation.

Dahms, D.E. (Univ. of Northern Iowa, Cedar Falls, IA (United States). Geography Dept.)

1992-01-01

4

Mineralization of soil organic matter initiated by the application of an available substrate to the profiles of surface and buried podzolic soils  

NASA Astrophysics Data System (ADS)

The priming effect (PE) initiated by the application of 14C-glucose was studied for copiotrophic microbial communities of organic horizons and for oligotrophic microbial communities of mineral soil horizons, as well as for mineral horizons of buried soils depleted in the input of fresh organic matter. The intensity of the PE depended on the reserves of Corg, the initial amount of the microbial biomass, and the enzymatic activity, which decreased from the organic to the mineral soil horizons. The ratio of the PE to the applied carbon was two times higher in the mineral horizons as compared with the organic horizons. This is explained by the predominance of K-strategists capable of decomposing difficultly available organic compounds in the mineral horizons, so that the turnover of the microbial biomass in the mineral horizons was more active than that in the organic horizons. The predominance of K-strategists was confirmed by the close correlation between the PE and the activity of the cellobiohydrolase enzyme decomposing cellulose ( R = 0.96). In general, the absolute value of the PE was controlled by the soil organic matter content, whereas the specific PE was controlled by the functional features of the microorganisms. It was shown that the functional features of the soil microorganisms remained unchanged under the conditions of their preservation in the buried soil.

Zhuravleva, A. I.; Yakimov, A. S.; Demkin, V. A.; Blagodatskaya, E. V.

2012-04-01

5

Discrimination of UXO buried under magnetic soil  

NASA Astrophysics Data System (ADS)

Electromagnetic induction (EMI) has become a promising technique for UXO detection and discrimination. In most studies the effect of the ground itself is assumed small and neglected. This assumption holds up relative to ground conductivity and corresponding induced electric currents. However experience shows that magnetic effects may sometimes be significant. Here we consider the case when the ground itself is mildly permeable, a common condition. Magnetic (i.e. permeable) soil could conceivably affect the EMI response of buried metallic targets in three ways: (1) the half space of soil itself produces a scattered field, dependent on the position of the sensor, which becomes part of the background; (2) The incident field that reaches the target and the response that reaches the sensor are altered by the air-ground interface; and (3) the frequency response of the target may be altered by changes in the ratio of its magnetic permeability to that of the ground in which it is buried. Regarding the first factor, analysis shows that the response of a half space to an above-ground dipole source should be flat across the EMI spectrum. By describing our actual sensor in terms of a collection of infinitesimal dipoles, we are thus able to calculate the response due to the ground alone as a function of antenna elevation and tilt. This can then be subtracted from the data as background. Examination of realistic ground parameters at UXO sites and reference to basic magneto-quasistatic solutions allows to discount the effects of the second and third factors. We then construct a forward model which takes the soil effect into account via the first factor, and apply the model in a pattern matching approach for UXO discrimination. Example results show that the effect of soil is important in some cases, and neglecting soil effect may cause quite significant difficulty or error in UXO discrimination.

Sun, K.; O'Neill, K.; Shubitidze, F.; Shamatava, I.; Paulsen, K. D.

2005-06-01

6

Phosphatase activity in the surface and buried chestnut soils of the Volga-Don interfluve  

NASA Astrophysics Data System (ADS)

The phosphatase activity (PA) was studied in the chestnut paleosols buried in 1718-1720 under the Anna Ivanovna rampart in the southern part of the Privolzhskaya Upland and in the middle of the third millennium BC under the burial mound of the Bronze Age on the Northern Yergeni Upland; the background analogues of these soils were also examined. The PA values in the fresh soil samples varied from 2.5 to 37 mg of P2O5/10 g of soil per h with maximums in the A1 horizon of the surface soils and in the B1 horizon of the paleosols. The PA values depended on the time of storage of the samples: with time, they increased by 2.6-2.9 times in the A1 horizon of the background surface soil and decreased by 20-60% in the other soil samples. The specific distribution patterns of the PA values in the soil profiles remained the same independently of the time of storage of the samples. Relatively small amounts of the soil samples were sufficient for the reliable determination of the PA: 1-2 g for the A1 horizon and 3-5 g for the B1 and B2 horizons. The time of incubation with the substrate had to be increased up to 4 h for the long-stored samples.

Khomutova, T. E.; Demkina, T. S.; Kashirskaya, N. N.; Demkin, V. A.

2012-04-01

7

50 Years of Soil Survey Horizons  

NASA Astrophysics Data System (ADS)

Soil Survey Horizons (SSH) started in 1960 as the newsletter of the North Central Soil Survey, United States, with an editorial board consisting of Francis D. Hole, O.C. Rogers, and Donald F. Post. SSH was started to provide an outlet for field observations of soils because the founders of SSH felt that other outlets for such communications were disappearing. Francis Hole's office at the University of Wisconsin served as the point of publication for SSH through its first 15 years, but in 1975 the Soil Science Society of America (SSSA) began handling its publication. Initially SSSA published SSH but did not assume ownership or editorial control of the publication until 2005. Over the years there has been a steady increase in the amount of material published in each volume of SSH. Significant improvements to Soil Survey Horizons over the years have included a move to full 8.5" x 11" pages and publication in color. Future improvements will include online publication and expansion to an international audience, including recruitement of international members for the editorial board.

Brevik, E. C.

2012-04-01

8

Pedogenesis in Lutitic Cr Horizons of Gypsiferous Soils  

Microsoft Academic Search

crystals. However, to properly understand the genesis and the properties of the soil horizons in areas with The weathering of lutites in aridic or near-aridic environments ubiquitous gypsum, one needs to take into account the leading to soil horizons is not well known. Lutites are a common soil generalized formation of gypsic pedofeatures, that can parent rock composed of silt

O. Artieda; J. Herrero

2003-01-01

9

Soil organic matter stabilization in buried paleosols of the Great Plains  

NASA Astrophysics Data System (ADS)

Understanding the mechanisms that control soil organic matter (SOM) stabilization is important for understanding how soil carbon is sequestered over millennia, and for predicting how future disturbances may affect soil carbon stocks. We are studying the mechanisms controlling SOM stabilization in the Brady Soil, a buried paleosol in Holocene loess deposits spanning much of the central Great Plains of the United States. The Brady Soil developed 9,000-13,500 years ago during a time of warming and drying that resulted in a shift from C3 to C4 dominated plants. The Brady soil is unusual in that it has very dark coloring, although it contains less than <1 % organic C. Although the Brady Soil has low C concentrations, it contains significant carbon stocks due to its thickness (~1 m) and wide geographic extent. We sampled the modern surface A horizon and multiple buried paleosol horizons from two roadcuts near Wauneta in southwestern Nebraska. We are using isotopic, spectroscopic, and geochemical techniques to examine what plant and microbially-derived compounds are have been preserved in the Brady Soil. We used a combined physical density and particle size fractionation method to separate particulate organic matter associated with minerals from that within and outside of soil aggregates. We found the largest and darkest amounts of organic C in aggregate-protected SOM greater than 20 µm in diameter. Density and textural fractionation revealed that much of the SOM is bound within aggregates, indicating that protection within aggregates is a major contributor to SOM- stabilization in the Brady Soil. We are conducting a long-term lab soil incubation with soils collected from the modern A horizon and the Brady Soil to determine if the buried SOM becomes microbially available when exposed to the modern atmosphere. We are measuring potential rates of respiration and production of CH4 and N2O. Results so far show respiration rates at field moisture for both modern and buried horizons are limited by water, suggesting dry environmental conditions may have helped to preserve SOM in the Brady Soil. We are investigating the potential for chemical stabilization of the dark SOM preserved in the buried paleosol by characterizing C chemistry using solid-state 13C-NMR spectroscopy. Furthermore, we plan to use lipid analyses and pyrolysis GC/MS to determine likely sources for the SOM: microbial vs plant. Combining information on the physical location of SOM in the soil, its chemical composition, decomposability, and radiocarbon based mean residence time estimates will allow us to determine (a) the source of the dark coloration in the Brady soil, (b) the mechanisms that have contributed to its preservation for the last 10,000 years, and (c) the likelihood this large soil C stock will be lost to the atmosphere if exposed during disturbance.

Chaopricha, N. T.; Marin-Spiotta, E.; Mason, J. A.; Mueller, C. W.

2010-12-01

10

Continuum soil modeling in the static analysis of buried structures  

SciTech Connect

Soil loading traditionally has been modeled as a hydrostatic pressure, a practice acceptable for many design applications. In the analyses of buried structure with predictive goals, soil compliance and load redistribution in the presence of soil plasticity are important factors to consider in determining the appropriate response of the structure. In the analysis of existing buried waste-storage tanks at the US Department of Energy`s Hanford Site, three soil-tank interaction modeling considerations are addressed. First, the soil interacts with the tank as the tank expands and contracts during thermal cycles associated with changes in the heat generated by the waste material as a result of additions and subtractions of the waste. Second, the soil transfers loads from the surface to the tank and provides support by resisting radial displacement of the tank haunch. Third, conventional finite-element mesh development causes artificial stress concentrations in the soil associated with differential settlement.

Julyk, L.J.; Marlow, R.S.; Moore, C.J. [Westinghouse Hanford Co., Richland, WA (United States); Day, J.P.; Dyrness, A.D. [Advent Engineering Services, Inc., San Ramon, CA (United States)

1993-10-01

11

Numerical analysis of an experimental pipe buried in swelling soil  

Microsoft Academic Search

This paper investigates the pipe–soil interaction for pipes buried in expansive soil when subjected to swelling soil movement due to increase in moisture content. A laboratory experiment has been undertaken on a plastic pipe in a large-scale pipe box. A three dimensional numerical model is developed to analyse the pipe response, using FLAC3D computer program. The pipe is assumed to

Pathmanathan Rajeev; Jayantha Kodikara

2011-01-01

12

Buried mine and soil temperature prediction by numerical model  

Microsoft Academic Search

The main disadvantage of applying IR thermal images for detection of buried mines, is the present of various false indications in thermograms together with strong influence of the environmental conditions for final results. A simple use of IRT equipment with better temperature resolution would not help in distinguishing mines, since noise does not come form camera but from the soil

Piotr Pregowski; Waldemar Swiderski; R. T. Walczak; K. Lamorski

2000-01-01

13

Buried soil organic inclusions in non-sorted circles fields in northern Sweden: Age and Paleoclimatic context  

NASA Astrophysics Data System (ADS)

Although burial of surface organic soil horizons into deeper mineral soil layers helps drive the long-term buildup of carbon in arctic soils, when and why buried horizons formed as result of cryoturbation in northern Sweden remain unclear. In this study, we used 14C and 210Pb dating to assess when organic matter was buried within non-sorted circles fields near Abisko in northern Sweden. In addition, we used aerial photos from 1959 and 2008 to detect eventual trends in cryogenic activities during this period. We found that organic matter from former organic horizons (stratigraphically intact or partly fragmented) corresponds to three major periods: 0-100 A.D., 900-1250 A.D., and 1650-1950 A.D. The latter two periods were indicated by several dated samples, while the extent of the oldest period is more uncertainty (indicated by only one sample). The aerial photos suggest a net overgrowth by shrub vegetation of previously exposed mineral soil surfaces since 1959. This overgrowth trend was seen in most of the studied fields (92 out of 137 analyzed fields), indicating that the cryogenic activity has mainly decreased in studied non-sorted circles fields since the 1950s. This latter interpretation is also supported by the absence of buried organic layers formed during the last decades. We suggest that the organic matter was buried during the transition from longer cold periods to warmer conditions. We believe these climatic shifts could have triggered regional scale burial of soil organic matter and thus affected how these soils sequestered carbon.

Becher, Marina; Olid, Carolina; Klaminder, Jonatan

2013-03-01

14

Soil science horizons: Progress and prospects  

NASA Astrophysics Data System (ADS)

The main tendencies in the development of Russian soil science after the previous congress (Novosibirsk, 2004) are analyzed. The major achievements of Russian pedologists in the field of the geography and cartography of soils are outlined, including the development of new small-scale maps of Russia and particular regions and the study of soils of northern territories. The latest data on the emission of greenhouse gases from soils of Russia are analyzed. It is shown that expectations of a sharp increase in the emission of greenhouse gases from the soils of northern territories in relation to the predicted climate warming are groundless. At the same time, the widespread development of soil degradation processes and the conversion of former agricultural lands into other land categories are the matters of deep concern of Russian soil scientists. The need in activation of the work of the Dokuchaev Soil Science Society in the field of the development of legislative regulations of soil management and rational use of land resources is stressed. The organization of the Soil Conservation Service in Russia, the adoption a federal law on soil conservation, the development of the national soil-geographic database, and the practical implementation of soil certification and soil-ecological monitoring are considered to be major challenges facing Russian soil scientists in the nearest future.

Shoba, S. A.

2009-05-01

15

Soil science horizons: Progress and prospects  

Microsoft Academic Search

The main tendencies in the development of Russian soil science after the previous congress (Novosibirsk, 2004) are analyzed. The major achievements of Russian pedologists in the field of the geography and cartography of soils are outlined, including the development of new small-scale maps of Russia and particular regions and the study of soils of northern territories. The latest data on

S. A. Shoba

2009-01-01

16

Soil science horizons: Progress and prospects  

Microsoft Academic Search

The main tendencies in the development of Russian soil science after the previous congress (Novosibirsk, 2004) are analyzed.\\u000a The major achievements of Russian pedologists in the field of the geography and cartography of soils are outlined, including\\u000a the development of new small-scale maps of Russia and particular regions and the study of soils of northern territories. The\\u000a latest data on

S. A. Shoba

2009-01-01

17

Molecular identification of ectomycorrhizal mycelium in soil horizons  

Microsoft Academic Search

Molecular identification techniques based on total DNA extraction provide a unique tool for identification of mycelium in soil. Using molecular identification techniques, the ectomycorrhizal (EM) fungal community under coniferous vegetation was analyzed. Soil samples were taken at different depths from four horizons of a podzol profile. A basidiomycete-specific primer pair (ITS1F-ITS4B) was used to amplify fungal internal transcribed spacer (ITS)

Renske Landeweert; Paula Leeflang; Thom W. Kuyper; Ellis Hoffland; Anna Rosling; Karel Wernars; Eric Smit

2003-01-01

18

The microbial biomass in paleosols buried under kurgans and in recent soils in the steppe zone of the Lower Volga region  

NASA Astrophysics Data System (ADS)

The total microbial biomass (TMB) was assessed in the chestnut and light chestnut soils and in the paleosols under burial mounds (steppe kurgans) in the Lower Volga region on the basis of data on the organic carbon content in the extracted microbial fraction supplemented with the data on the extraction completeness as a conversion coefficient. The completeness of the microbial fraction extraction was determined by direct counting of the microbial cells and colony-forming units (on plates with soil agar). The total microbial biomass varied from 400 to 6600 ?g of C/soil. Its values in the buried soils were 3-5 times lower than those in the surface soils. The TMB distribution in the buried chestnut soil profile was close to that in its modern analogue (with the minimum in the B1 horizon). In the buried light chestnut paleosols, the TMB values usually increased down the profile; in the recent light chestnut soils, the maximum TMB values were found in the uppermost horizon.

Kashirskaya, N. N.; Khomutova, T. E.; Demkina, T. S.; Demkin, V. A.

2009-05-01

19

Software for simulation of electromagnetic waves propagation through the soil with buried objects  

Microsoft Academic Search

The software for simulation of electrmagnetic waves propagation through the soil layered structure with shallow buried objects has been described in the paper. The simulation is based on the finite difference time domain (FDTD) method and allows to define ten layers of soil and four buried cubicoid objects. Such virtual ground penetrating radar (GPR) system seems to be useful for

Mateusz Pasternak; Dariusz Silko

2010-01-01

20

Merging Horizons—Soil Science and Soil Art  

Microsoft Academic Search

A collection of canvases caked in colorful arrangements of browns and grays competes for space alongside an extensive accumulation of soil samples, old lab equipment, and remnants of assorted research projects in the basement of the Gorbatschow Building of the Berlin University of Technology. Remains of an artistic field experiment conducted last summer, the canvases mark the Soil Protection Department’s

Alexandra Toland; Gerd Wessolek

21

Soil restraint on buckling oil and gas pipelines buried in lumpy clay fill  

Microsoft Academic Search

Offshore pipelines used for oil and gas transportation are often buried to avoid damage from fishing activities and to provide thermal insulation. The soil cover also provides resistance to upward movement of the pipe caused by thermally-induced axial loading, a phenomenon known as upheaval buckling. Previous research has been conducted to investigate the available uplift resistance of a buried object

C. Y. Cheuk; W. A. Take; M. D. Bolton; J. R. M. S. Oliveira

2007-01-01

22

Lanthanides in humic acids of soils, paleosols and cultural horizons (Southern Urals, Russia)  

NASA Astrophysics Data System (ADS)

In recent years, commercial interest in this element group increases. As consequence, their content may increase in environment, including soil and soil components. This requires quantitative estimations of rare metal accumulation by soils and their humic acids. The latter began to be actively used as fertilizers and it is alarming, because information about rare element participation (including lanthanides) in metabolism of live organisms is inconsistent. There was investigated lanthanide content in humic acids extracted from humus horizons of different objects of archaeological site Steppe 7 (Southern Urals, Russia). Humic acids were extracted from modern background soils and paleosols and cultural horizons of the Bronze Age as well. According to archaeological data burial of paleosols under a barrow and formation of the cultural layer (CL) took place 3600 and 3300-3200 years BP, respectively. The area of the site is located in the forest-steppe landscape, far from industrial plants. Lanthanides in soils are immobile elements, and such number of objects will allow to receive information about their content changing over time and to have more detailed basis for the future monitoring of this territory as well. Humic acids were precipitated from 0,1 n NaOH extraction after preliminary decalcification. Cleaning of humic acid preparations by 6N HCl or HF+HCl was not carried out. Determination of La, Ce, Sm, Eu, Tb, Yb and Lu was performed by multi-element neutron-activation analysis. According to carried out diagnostics and reconstruction of natural conditions of all object formation, all objects correspond to steppe type landscape with a different level of humidity. Analysis of received data has shown that cerium is presented in humic acid preparations in the largest quantities among lanthanides (on average 4,0-6,6 mg/kg of preparation mass). The average content of samarium, europium, ytterbium and lutetium in the humic acids in the order of magnitude ranges from 0.13 to 0.49 mg/kg, terbium and lutetium - two orders of magnitude. The quantities determined by us for lanthanum is also high at 1,9-3,3 mg/kg. In this case all lanthanides in modern soils have the degree of accumulation in humic acids distinguished from other objects: Ce>La>Sm>Yb>Eu>Tb>Lu. In the paleosols and cultural layer these series are identical: Ce>La>Yb>Sm>Eu>Lu>Tb. There is suggested the approach to direct estimation of share of the lanthanides connected by humic acids in the their total soil pool which includes recalculation of the content of separate elements in humic acid preparations on carbon of soil humic acids (in mg/kg) and the subsequent correlation of their quantities. The content of the total organic carbon in soil, a share of humic acids as a humus part, the lanthanide content and weight carbon percentage in humic acid preparations were considered during recalculations. The results have shown that the highest shares of all elements are found in modern background soils, the lowest - in the soils buried under barrows. The total percentage of all lanthanides in humic acids is 4.63% in relation to their content in modern soil, 1.56% - in CL and 1.36% - in buried paleosols.

Dergacheva, Maria; Nekrasova, Olga

2013-04-01

23

PH BUFFERING IN FOREST SOIL ORGANIC HORIZONS: RELEVANCE TO ACID PRECIPITATION  

EPA Science Inventory

Samples of organic surface horizons (Oi, Oe, Oa) from New York State forest soils were equilibrated with 0 to 20 cmol HNO3 Kg(-1) soil in the laboratory by a batch technique designed to simulate reactions of acid precipitation with forest floors. Each organic horizon retained a c...

24

A new compilation of depth to calcic horizons in soils for interpreting former rainfall from paleosols  

Microsoft Academic Search

Many studies since the seminal work of Hans Jenny in 1941 have demonstrated that the depth of the calcic horizon in soils can be related to mean annual rainfall during their development. Depth to calcic horizon is not the same as depth of leaching of carbonate, which increases with time, not rainfall. A new compilation of 381 soils of known

GJ Retallack

1992-01-01

25

Soil–structure interaction for deeply buried corrugated steel pipes Part II: Imperfect trench installation  

Microsoft Academic Search

The potential benefits of the imperfect trench installation method were studied for corrugated steel pipes. The imperfect trench installation method has mostly been used to reduce earth pressure on buried rigid pipes by inducing reverse soil arching over the pipe. Because corrugated steel pipes are relatively flexible, they induce a small amount of reverse soil arching. Therefore, there has been

Junsuk Kang; Frazier Parker; Chai H. Yoo

2008-01-01

26

Interactions of low-level, liquid radioactive wastes with soils. 3. Interaction of waste radionuclides with soil from horizons of two soil series  

Microsoft Academic Search

We interacted a low-level radioactive waste with the respective horizons of two soils series, the Fuquay and the Fayette. The sorption of the soluble radionuclides was determined by batch reaction methods. Cesium-137 was sorbed to a very high degree, greater than 95 percent, and that degree of sorption was independent of both the soil horizon and the soil series. Uranium

W. L. Polzer; E. B. Fowler; E. H. Essington

1981-01-01

27

Role and development of soil parameters for seismic responses of buried lifelines  

SciTech Connect

Buried lifelines, e.g. oil, gas, water and sewer pipelines have been damaged heavily in recent earthquakes such as 1971 San Fernando Earthquake, in U.S.A., 1976 Tangshan Earthquake, in China, and 1978 MiyagiKen-Oki Earthquake, in Japan, among others. Researchers on the seismic performance of these buried lifelines have been initiated in the United States and many other countries. Various analytical models have been proposed. However, only limited experimental investigations are available. The sources of earthquake damage to buried lifelines include landslide, tectonic uplift-subsidence, soil liquefaction, fault displacement and ground shaking (effects of wave propagation). This paper is concerned with the behavior of buried lifeline systems subjected to surface faulting and ground shaking. The role and development of soil parameters that significantly influence the seismic responses are discussed. The scope of this paper is to examine analytically the influence of various soil and soilstructure interaction parameters to the seismic responses of buried pipelines, to report the currently available physical data of these and related parameters for immediate applications, and to describe the experiments to obtain additional information on soil resistant characteristics to longitudinal pipe motions.

Wang, L.R.L.

1983-01-01

28

Soil Series Survey of Selected Study Areas in Thailand Appendix D: Soil Survey of the Pran Buri Area.  

National Technical Information Service (NTIS)

The soil survey conducted in the Pran Buri study area covered an area of approximately 570 sq km (220 sq mi). Reconnaissance was made along all accessible roads and tracks. Soils were studied at road cuts and at exposures along drainage channels. In areas...

L. Moncharoen S. Charoenpong F. J. Dent

1966-01-01

29

Soil Properties Influencing Stability of Structure of B-horizons of Ultisols in Semiarid Nsukka, Eastern Nigeria  

Microsoft Academic Search

The argillic B-horizons of some ultisols are dense, often limiting root growths and developing some poor physical properties. Knowledge of the soil properties that influence this poor structural development is needed for better management of the soils. Ten Bt-horizons from different soil profiles were sampled for determination of soil structural properties. The aim was to determine the influence of measurable

C. A. IGWE

2004-01-01

30

Buried black soils surrounding the white roof of Africa as regional carbon storage hotspot  

NASA Astrophysics Data System (ADS)

Mt. Kilimanjaro, the at least still "white roof" of Africa, attracts much attention because of its dramatically shrinking ice caps. By contrast, it was discovered only recently that intriguing paleosol sequences with buried and often strikingly black soils developed along the slopes of Mt. Kilimanjaro during the Late Quaternary. In our study we investigated in detail the soil organic carbon (SOC) contents and SOC stocks of soil profiles which are situated along two altitudinal transects; one along the humid southern slopes and the other one along the more arid northern slopes. We found up to 3 m thick paleosol sequences occurring almost area-wide particularly in the montane forest zone. SOC contents are remarkable high with values of up to more than 10%, indicating high preservation of soil organic matter (SOM). We suggest that the SOM preservation is favoured by several factors, such as (i) the burial by aeolian deposition, (ii) lower temperatures and (iii) more resistant Erica litter during glacial periods, (iv) formation of stable organo-mineral complexes and (v) high black carbon (BC) contents. The SOC-rich buried black soils account for mean SOC stocks of ~82 kg m-2 in the montane rainforest. Extrapolating this SOC storage and comparing it with the SOC storage achieved by the surrounding savannah soils of the Maasai Steppe highlights that the buried black soils are a prominent regional carbon storage hotspot.

Zech, M.; Hörold, C.; Leiber-Sauheitl, K.; Hemp, A.; Zech, W.

2012-04-01

31

Failure mechanisms of buried pipelines under fault movement and soil liquefaction  

Microsoft Academic Search

Lifelines, such as oil and gas transmission lines and water and sewer pipelines, have been damaged heavily in recent earthquakes. The damages of these lifelines have caused major, catastrophic disruption of essential service to human needs. Two seismic hazards are a) fault movement and b) soil liquefaction. In the investigation of fault movement, a non-linear analysis for a buried pipeline

Yeh

1983-01-01

32

Genetic identification of degraded DNA samples buried in different types of soil  

Microsoft Academic Search

Biological samples buried in different types of soil are often found in crime scenes. These samples are usually highly degraded which difficult their analysis. Several factors contribute to the degradation of biological material including temperature variation, humidity, UV light and especially the presence of microorganisms.Blood was collected from three non-related male donors and blood stains were made in fabrics such

V. Bogas; M. Carvalho; M. J. Anjos; M. F. Pinheiro; F. Corte-Real

2009-01-01

33

Explosives-related chemical concentrations in surface soils over buried land mines  

Microsoft Academic Search

Night Vision Electronic Sensors Directorate (NVESD) has initiated a program for land mine sensor development based upon explosives-related chemical (ERC) detection. As part of the NVESD ERC sensor program, we have sampled soils surrounding buried land mines at the experimental mine lanes, U.S. Army Test Site, with the assistance of the Army Corps of Engineers, Cold Regions Research and Engineering

Kira D. Hutchinson; Scott L. Grossman; Thomas F. Jenkins; Kelly D. Sherbondy

2002-01-01

34

Soil–structure interaction for deeply buried corrugated steel pipes Part I: Embankment installation  

Microsoft Academic Search

The strengths of buried corrugated steel pipes were studied. There are considerable differences in the fundamental mechanics of earth pressure distribution on rigid pipes and flexible pipes. Corrugated steel pipes are categorized as semi-flexible. The mechanics of soil arching for corrugated steel pipes, therefore, are slightly different from rigid or flexible pipes. Predictor equations for arching factors, deflections, and maximum

Junsuk Kang; Frazier Parker; Chai H. Yoo

2008-01-01

35

Sorption of acetochlor, S-metolachlor, and atrazine in surface and subsurface soil horizons of Argentina.  

PubMed

Understanding herbicide sorption within soil profiles is the first step to predicting their behavior and leaching potential. Laboratory studies were conducted to determine the influence of surface and subsurface soil properties on acetochlor, atrazine, and S-metolachlor sorption. Soil samples were taken from horizons A, B, and C of two loamy soils of the humid pampas of Argentina under no-till management; horizon A was divided into two layers, A(0) (0-5 cm) and A(1) (5 cm to the full thickness of an A horizon). Sorption isotherms were determined from each sampled horizon using the batch equilibrium method and seven concentrations (0, 0.1, 0.5, 2.0, 5.0, 10.0, and 20.0 mg?L(-1)). Sorption affinity of herbicides was approximated by the Freundlich equation. The sorption strength K(f) (mg(1 - 1/n) kg(-1) L(1/n) ) over the soils and horizons studied followed the order S-metolachlor (16.51-29.19)?>?atrazine (4.85-12.34) ? acetochlor (5.17-11.97), which was closely related to the hydrophobicity of herbicides expressed as octanol-water partition coefficient (K(OW) ). The K(f) values of the three herbicides were positively correlated with soil organic carbon, with a significance of p < 0.01. Values of K(f) for the three herbicides decreased with depth in the two soils, indicating greater sorption onto surficial soil horizons and possibly a delayed transport toward subsurface soils and subsequent pollution of groundwater. PMID:21692102

Bedmar, Francisco; Daniel, Peter E; Costa, José L; Giménez, Daniel

2011-07-13

36

Acidity of KCl extracts from organic horizons of podzolic soils: Sources and possible equilibria  

NASA Astrophysics Data System (ADS)

Samples from the organic horizons of taiga podzolic soils of the Komi Republic were studied, and the possible equilibria established in the soil-KCl solution system ( c = 1 mol/l) at the determination of the exchangeable acidity by the Sokolov method were examined. It was shown that the exchangeable acidity was due to aluminum(III) ions in 6% of the samples with pHKCl?4 and due to the H+ ions formed during the dissociation of water-soluble organic acids in the other samples. A group of samples from the horizons in which Fe3+ ions could appreciably contribute to the soil acidity was discriminated.

Shamrikova, E. V.

2010-07-01

37

14 C dating of buried soils in the volcanic chaine des puys (France)  

Microsoft Academic Search

Apparent ages of the paleosoils buried under ash deposits or lava flows cannot be used without a correct understanding of\\u000a the soil type buried by the volcanic event.\\u000a \\u000a Considering the apparent ages measured in the French «Massif Central» we can accept the rejuvenation of 500 years generally\\u000a used if mollisols (sol bruns) are concerned.\\u000a \\u000a \\u000a \\u000a The rejuvenation can reach 4,000 years

J. M. Hetier; B. Guillet; R. Brousse; G. Delibrajs; R. C. Maury

1983-01-01

38

The Experimental Earthwork at Wareham, Dorset After 33 Years: Changes to the Buried LFH and Ah Horizons  

Microsoft Academic Search

This paper reports upon the effects of 33 years of burial upon the micromorphology, chemistry and magnetic susceptibility of the topsoil of a lowland podzol, buried beneath the bank of the Experimental Earthwork built at Wareham, Dorset, U.K., in 1963. The turf-cored sand bank and associated ditch were constructed to replicate features of archaeological monuments found on acid heathland podzols.

Richard I. Macphail; John Crowther; Tim G. Acott; Martin G. Bell; Jill M. Cruise

2003-01-01

39

Concerning Genesis of the Buried Organic Matter in Tundra Soil.  

National Technical Information Service (NTIS)

Ever since the presence of a deep zone of concentrated organic matter was first reported in arctic Tundra soils of northern Alaska, there have been a number of questions relative to the origin of the organic material. It is well known that frost action in...

J. C. F. Tedrow

1964-01-01

40

Water and nitrate distributions as affected by layered-textural soil and buried dripline depth under subsurface drip fertigation  

Microsoft Academic Search

Laboratory experiments were conducted to investigate the distributions of water and nitrate from a buried dripline discharging\\u000a an ammonium nitrate solution in uniform and layered-textural soils. Two layered soils, a sandy-over-loam soil (SL) and a loam-sandy-loam\\u000a soil (LSL), and two uniform soils of sandy (S) and loam (L) were tested. The experimental results demonstrated that dripline\\u000a depth and layered-textural soil

Jiusheng LiYuchun Liu; Yuchun Liu

41

Chemical Soil Physics Phenomena for Chemical Sensing of Buried UXO  

SciTech Connect

Technology development efforts are under way to apply chemical sensors to discriminate inert ordnance and clutter from live munitions that remain a threat to reutilization of military ranges. However, the chemical signature is affected by multiple environmental phenomena that can enhance or reduce its presence and transport behavior, and can affect the distribution of the chemical signature in the environment. For example, the chemical can be present in the vapor, aqueous, and solid phases. The distribution of the chemical among these phases, including the spatial distribution, is key in designing appropriate detectors, e.g., gas, aqueous or solid phase sampling instruments. A fundamental understanding of the environmental conditions that affect the chemical signature is needed to describe the favorable and unfavorable conditions of a chemical detector based survey to minimize the consequences of a false negative. UXO source emission measurements are being made to estimate the chemical flux from a limited set of ordnance items. Phase partitioning analysis has been completed to show what the expected concentrations of chemical analytes would be fi-om total concentrations measured in the soil. The soil moisture content in the dry region has been shown to be critical in the attenuation of soil gas concentrations by increased sorption to soil particles. Numerical simulation tools have been adapted to include surface boundary conditions such as solar radiation, surface boundary layer (which is a function of wind speed), precipitation and evaporation, and plant cover/root density to allow transport modeling and evaluate long term processes. Results of this work will provide performance targets for sensor developers and support operational decisions regarding field deployments.

Phelan, James, M.; Webb, Stephen W.

1999-06-14

42

Thermal analysis of soil-buried oxo-biodegradable polyethylene based blends  

Microsoft Academic Search

Low-density polyethylene (LDPE) blended with poly(3-hydroxybutyrate) (PHB) and additivated with pro-oxidant were soil buried\\u000a for 180 days and characterized using thermogravimetry (TG) and differential scanning calorimetry (DSC). TG data showed that\\u000a both onset and maximum rate degradation temperatures decreased as a function of biodegradation time. Apparent activation energies\\u000a (E\\u000a a) using the Broido integral method decreased with the burial time increasing.

Sílvia Maria Martelli; Elizabeth Grillo Fernandes; Emo Chiellini

2009-01-01

43

Estimating depth to argillic soil horizons using apparent electrical conductivity  

Technology Transfer Automated Retrieval System (TEKTRAN)

Maps of apparent electrical conductivity (ECa) of the soil profile are widely used in precision agriculture practice and research. A number of ECa sensors are commercially available, each with a unique response function (i.e., the relative contribution of soil at each depth to the integrated ECa rea...

44

Effects of ecological succession on surface mineral horizons in Japanese volcanic ash soil  

Microsoft Academic Search

Japanese volcanic ash soils have very thick and dark-colored A horizons with large amounts of black humic acids which are characterized by their extremely high aromatic structure and stabilities such as black carbon. Nevertheless, the disappearance of the melanic epipedon with a decreasing aromatic C and increasing alkyl C proportion of humic acids was observed in ecological succession for only

Yasuo Iimura; Mari Fujimoto; Mitsuru Hirota; Kenji Tamura; Teruo Higashi; Koyo Yonebayashi; Nobuhide Fujitake

2010-01-01

45

Vapor-phase transport of explosives from buried sources in soils.  

PubMed

The fate and transport of explosives in the soil pore vapor spaces affects both the potential detection of buried ordnance by chemical sensors and vadose zone transport of explosives residues. The efficacy of chemical sensors and their potential usefulness for detecting buried unexploded ordnance (UXO) is difficult to determine without understanding how its chemical signatures are transported through soil. The objectives of this study were to quantify chemical signature transport through soils under various environmental conditions in unsaturated soils and to develop a model for the same. Flux chambers, large soil containers, and batch tests were used to determine explosives signature movement and process descriptors for model development. Low signatures were observed for explosives (2,4-dinitrotoluene, 2,6-dinitrotoluene, and 1,3-dinitrobenzene) under all environmental conditions. A diffusion model was used to describe the chemical transport mechanism in the soil pore air. The soil-air partition constant was treated as a fit parameter in the model owing to the uncertainty in its a priori estimation. The model predictions of the trends in experimental fluxes and the soil concentration were only marginal at best. It was concluded that better estimates of the partition constant are required for more accurate estimation of the chemical concentration at the soil-air interface. Chemical sensors will need to be very sensitive because of low signatures. However, this may result in many false alarms because of explosives residues not associated with UXO on firing ranges. Low explosives signatures also should result in insignificant air environmental exposures. PMID:15648390

Ravikrishna, Raghunathan; Valsaraj, Kalliat T; Price, Cynthia B; Brannon, James M; Hayes, Charolett A; Yost, Sally L

2004-12-01

46

Failure mechanisms of buried pipelines under fault movement and soil liquefaction  

SciTech Connect

Lifelines, such as oil and gas transmission lines and water and sewer pipelines, have been damaged heavily in recent earthquakes. The damages of these lifelines have caused major, catastrophic disruption of essential service to human needs. Two seismic hazards are a) fault movement and b) soil liquefaction. In the investigation of fault movement, a non-linear analysis for a buried pipeline subjected to tensile strike-slip fault is proposed with following conditions: 1) the conditions of using elastic foundation for the far end of the pipe and the ultimate passive soil pressure near the fault are used to derive the basic equations of a pipeline crossing an active fault; and 2) an iterative method is used to solve the non-linear equations induced from the non-linearity of material and soil characteristics and large displacement. This study also discusses the design criteria for buried pipelines subjected to various fault movement and other design parameters. An initial research effort to investigate the performance of a pipeline in a soil liquefaction environment during earthquakes is described. The pipeline is subjected to longitudinal wave propagation at the time of liquefaction of soil deposits. A simplified pipe model on a time dependent elastic foundation is proposed to stimulate a liquefaction situation of a liquefiable zone during earthquakes and the finite difference technique coupled with a time-increment computer solution is employed to determine the dynamic responses of the proposed model numerically.

Yeh, Y.H.

1983-01-01

47

Hydraulic and thermal properties of soil samples from the buried waste test facility  

SciTech Connect

In shallow land burial, the most common disposal method for low-level waste, waste containers are placed in shallow trenches and covered with natural sediment material. To design such a facility requires an in-depth understanding of the infiltration and evaporation processes taking place at the soil surface and the effect these processes have on the amount of water cycling through a burial zone. At the DOE Hanford Site in Richland, Washington, a field installation called the Buried Waste Test Facility (BWTF) has been constructed to study unsaturated soil water and contaminant transport. PNL is collecting data at the BWTF to help explain soil water movement at shallow depths, and specifically evaporation from bare sols. The data presented here represent the initial phase of a cooperative effort between PNL and Washington State University to use data collected at the BWFT.

Cass, A.; Campbell, G.S.; Jones, T.L.

1981-10-01

48

pH buffering in forest-soil organic horizons: relevance to acid precipitation  

SciTech Connect

Samples of organic surface horizons (Oi, Oe, Oa) from New York State forest soils were equilibrated with 0 to 20 cmol HNO/sub 3/ Kg(-1) soil in the laboratory by a batch technique designed to simulate reactions of acid precipitation with forest floors. Each organic horizon retained a constant percentage of added H(1+)(67-96%) regardless of quantity added and buffer capacities of the samples ranged from 18 to 36 cmol (H+)kg-1(pH unit) (-1), an order of magnitude higher than those measured in underlying mineral horizons. Calcium was the dominant cation in unacidified equilibrium solutions, and its concentration changed the most in response to acidification of the soils. Aluminum contributed <1% to total cationic charge in solution and Fe concentration decreased upon addition of up to at least 5 cmol (H+)kg-1. From 38 to 79% of H/sup +/ removed by the soils was not balanced by increased in soluble Ca, Mg, K, Mn, Fe, Zn, Al, and Cu, and buffering by soluble organic and inorganic constituents accounted for 8 to 58% of H/sup +/ removal.

James, B.R.; Riha, S.J.

1986-01-01

49

Production of CO2 by surface and buried soils of the steppe zone under native and moistened conditions  

Microsoft Academic Search

Modern light chestnut and chestnut soils and their analogues buried under steppe kurgans in the southeastern part of the Russian Plain were studied in order to determine the rates of the CO2 production by these soils under the native (with the natural moisture content) and moistened (60% of the total water capacity) conditions. It was found that the rates of

T. S. Demkina; A. V. Borisov; V. A. Demkin

2010-01-01

50

Functional assays and metagenomic analyses reveals differences between the microbial communities inhabiting the soil horizons of a Norway spruce plantation.  

PubMed

In temperate ecosystems, acidic forest soils are among the most nutrient-poor terrestrial environments. In this context, the long-term differentiation of the forest soils into horizons may impact the assembly and the functions of the soil microbial communities. To gain a more comprehensive understanding of the ecology and functional potentials of these microbial communities, a suite of analyses including comparative metagenomics was applied on independent soil samples from a spruce plantation (Breuil-Chenue, France). The objectives were to assess whether the decreasing nutrient bioavailability and pH variations that naturally occurs between the organic and mineral horizons affects the soil microbial functional biodiversity. The 14 Gbp of pyrosequencing and Illumina sequences generated in this study revealed complex microbial communities dominated by bacteria. Detailed analyses showed that the organic soil horizon was significantly enriched in sequences related to Bacteria, Chordata, Arthropoda and Ascomycota. On the contrary the mineral horizon was significantly enriched in sequences related to Archaea. Our analyses also highlighted that the microbial communities inhabiting the two soil horizons differed significantly in their functional potentials according to functional assays and MG-RAST analyses, suggesting a functional specialisation of these microbial communities. Consistent with this specialisation, our shotgun metagenomic approach revealed a significant increase in the relative abundance of sequences related glycoside hydrolases in the organic horizon compared to the mineral horizon that was significantly enriched in glycoside transferases. This functional stratification according to the soil horizon was also confirmed by a significant correlation between the functional assays performed in this study and the functional metagenomic analyses. Together, our results suggest that the soil stratification and particularly the soil resource availability impact the functional diversity and to a lesser extent the taxonomic diversity of the bacterial communities. PMID:23418476

Uroz, Stéphane; Ioannidis, Panos; Lengelle, Juliette; Cébron, Aurélie; Morin, Emmanuelle; Buée, Marc; Martin, Francis

2013-02-13

51

Functional Assays and Metagenomic Analyses Reveals Differences between the Microbial Communities Inhabiting the Soil Horizons of a Norway Spruce Plantation  

PubMed Central

In temperate ecosystems, acidic forest soils are among the most nutrient-poor terrestrial environments. In this context, the long-term differentiation of the forest soils into horizons may impact the assembly and the functions of the soil microbial communities. To gain a more comprehensive understanding of the ecology and functional potentials of these microbial communities, a suite of analyses including comparative metagenomics was applied on independent soil samples from a spruce plantation (Breuil-Chenue, France). The objectives were to assess whether the decreasing nutrient bioavailability and pH variations that naturally occurs between the organic and mineral horizons affects the soil microbial functional biodiversity. The 14 Gbp of pyrosequencing and Illumina sequences generated in this study revealed complex microbial communities dominated by bacteria. Detailed analyses showed that the organic soil horizon was significantly enriched in sequences related to Bacteria, Chordata, Arthropoda and Ascomycota. On the contrary the mineral horizon was significantly enriched in sequences related to Archaea. Our analyses also highlighted that the microbial communities inhabiting the two soil horizons differed significantly in their functional potentials according to functional assays and MG-RAST analyses, suggesting a functional specialisation of these microbial communities. Consistent with this specialisation, our shotgun metagenomic approach revealed a significant increase in the relative abundance of sequences related glycoside hydrolases in the organic horizon compared to the mineral horizon that was significantly enriched in glycoside transferases. This functional stratification according to the soil horizon was also confirmed by a significant correlation between the functional assays performed in this study and the functional metagenomic analyses. Together, our results suggest that the soil stratification and particularly the soil resource availability impact the functional diversity and to a lesser extent the taxonomic diversity of the bacterial communities.

Uroz, Stephane; Ioannidis, Panos; Lengelle, Juliette; Cebron, Aurelie; Morin, Emmanuelle; Buee, Marc; Martin, Francis

2013-01-01

52

A new compilation of depth to calcic horizons in soils for interpreting former rainfall from paleosols  

SciTech Connect

Many studies since the seminal work of Hans Jenny in 1941 have demonstrated that the depth of the calcic horizon in soils can be related to mean annual rainfall during their development. Depth to calcic horizon is not the same as depth of leaching of carbonate, which increases with time, not rainfall. A new compilation of 381 soils of known rainfall from all continents as well as New Zealand and Greenland, including only moderately developed soils on sedimentary parent materials, gave a relationship between depth to calcic horizon (D in cm) and precipitation (P in mm) of D = -40.49-0.0852P-0.002455P[sup 2] with a correlation coefficient (r) of 0.78 and standard error ([sigma]) of [+-]33 cm. For interpreting paleosols the converse relationships is more useful (P = 139.6--6.388D--0.01303D[sup 2], with r = 0.79 and [sigma] = [+-]141 mm). Also worth considering for the interpretation of paleosols are the carbon dioxide composition of the atmosphere at the time they formed, the degree to which they have been eroded before burial, and the amount of compaction during burial. These problems are illustrated with the example of Eocene and Oligocene paleosols of Badlands National Park, South Dakota, which shows stepwise drying of paleoclimate during mid-Tertiary time.

Retallack, G.J. (Univ. of Oregon, Eugene, OR (United States). Dept. of Geological Sciences)

1992-01-01

53

The origin of lead in the organic horizon of tundra soils: atmospheric deposition, plant translocation from the mineral soil or soil mineral mixing?  

PubMed

Knowledge of the anthropogenic contribution to lead (Pb) concentrations in surface soils in high latitude ecosystems is central to our understanding of the extent of atmospheric Pb contamination. In this study, we reconstructed fallout of Pb at a remote sub-arctic region by using two ombrotrophic peat cores and assessed the extent to which this airborne Pb is able to explain the isotopic composition ((206)Pb/(207)Pb ratio) in the O-horizon of tundra soils. In the peat cores, long-range atmospheric fallout appeared to be the main source of Pb as indicated by temporal trends that followed the known European pollution history, i.e. accelerated fallout at the onset of industrialization and peak fallout around the 1960s-70s. The Pb isotopic composition of the O-horizon of podzolic tundra soil ((206)Pb/(207)Pb=1.170 ± 0.002; mean ± SD) overlapped with that of the peat ((206)Pb/(207)Pb=1.16 ± 0.01) representing a proxy for atmospheric aerosols, but was clearly different from that of the parent soil material ((206)Pb/(207)Pb=1.22-1.30). This finding indicated that long-range fallout of atmospheric Pb is the main driver of Pb accumulation in podzolic tundra soil. In O-horizons of tundra soil weakly affected by cryoturbation (cryosols) however, the input of Pb from the underlying mineral soil increased as indicated by (206)Pb/(207)Pb ratios of up to 1.20, a value closer to that of local soil minerals. Nevertheless, atmospheric Pb appeared to be the dominant source in this soil compartment. We conclude that Pb concentrations in the O-horizon of studied tundra soils - despite being much lower than in boreal soils and representative for one of the least exposed sites to atmospheric Pb contaminants in Europe - are mainly controlled by atmospheric inputs from distant anthropogenic sources. PMID:21820157

Klaminder, Jonatan; Farmer, John G; MacKenzie, Angus B

2011-08-04

54

Macro- and micromorphological features of genetic horizons in a solonetzic soil complex at the Dzhanybek Research Station  

NASA Astrophysics Data System (ADS)

The comparative analysis of macro- and microfabrics of soil horizons in a trench crossing a solonetzic soil complex on a virgin plot has shown incomplete correspondence between the macro- and micromorphological features. Solonetzic and solodic horizons and features are differently manifested in different types of soils. The soils of the complex are subjected to continuous transformation dictated by the general trend of the landscape evolution in the Caspian Lowland and by the local changes related to the activity of burrowing animals and fluctuations in the groundwater level. The current trends of evolutionary changes are reflected in the soil microfabrics and salt pedofeatures, whereas more ancient processes are recorded in the properties of the clayey plasma. In the soil of the microlow, the most complete correspondence between the macro- and micromorphological features is observed. At the microlevel, the horizons of this soil resemble the humus-accumulative and metamorphic horizons of dark-colored chernozem-like soils of vast mesodepressions. A variant of the soil evolution within the solonetzic complex is discussed.

Lebedeva-Verba, M. P.; Gerasimova, M. I.

2009-03-01

55

A geophysical and biochemical investigation of buried remains in contrasting soil textures in southern Ontario  

NASA Astrophysics Data System (ADS)

Ground penetrating radar (GPR) is a non-invasive, geophysical tool used for the detection of clandestine graves. GPR operates by detecting density differences in soil by the transmission of high frequency electromagnetic (EM) waves from an antenna. A 500 Megahertz (MHz) frequency antenna is typically used for forensic investigations, as it provides a suitable compromise between depth of penetration and sub-surface resolution. Domestic pig (Sus scrofa) carcasses were clothed in 100% cotton t-shirts and 50% cotton/50% polyester briefs, and buried at a consistent depth at three field sites of contrasting soil texture (silty clay loam, fine sand and fine sandy loam) in southern Ontario. GPR was used to detect and monitor the graves for a period of 14 months post burial. Analysis of collected data revealed that GPR had applicability in the detection of clandestine graves containing remains in silty clay loam and fine sandy loam soils, but was not suitable for detection in fine sandy soil. Specifically, within a fine sandy loam soil, there is the potential to estimate the post burial interval (PBI), as hyperbolic grave response was well defined at the beginning of the 14 month burial duration, but became less distinctive near the completion of the study. Following the detection of a clandestine grave containing a carcass, collection of gravesoil, tissue and textile samples is important for the estimation of the stage of decomposition and the post burial interval (PBI) of the remains. Throughout the decomposition process of a carcass, adipose tissue is subjected to hydrolytic enzymes that convert triglycerides to their corresponding unsaturated, saturated and salts of fatty acids. The composition of fatty acids in the decomposed tissue will vary with the post mortem period, but it is unknown what affect the soil texture has on lipid degradation. As decomposition proceeds, fatty acids can leach from the tissues into the surrounding burial environment. Fatty acid analysis of gravesoil, tissue and textile samples, exhumed at two, eleven and fourteen month post burial intervals, was conducted using diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS), attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy and gas chromatography-mass spectrometry (GC-MS). Infrared (IR) spectroscopy analysis of the samples provided a qualitative profile of lipid degradation. Analysis of gravesoil samples did not reveal IR spectroscopy bands attributable to fatty acid degradation or adipocere formation. IR spectroscopy analysis of tissue samples is applicable for the estimation of carcass decomposition in all of the soil textures tested. Results of textile IR spectroscopy analysis revealed limited potential to estimate the stage of carcass decomposition in silty clay loam soil. GC-MS was used to quantify the peak area ratio (area/int std area) (PAR) of myristic (C14:0), palmitic (C16:0), palmitoleic (C16:1), stearic (C18:0) and oleic (C18:1) acids. GC-MS results revealed that analysis of both tissue and textile samples can be useful in the estimation of the stage of decomposition and the PBI of carcasses in all three of the soil textures tested. The results of this research may have applicability within forensic investigations involving decomposing bodies by aiding in the location of clandestine graves in silty clay loam and fine sandy loam soil through the use of GPR. Infrared spectroscopy and GC-MS analysis of the fatty acid composition of tissue and textile samples may also be incorporated into investigational protocols to aid in the estimation of the stage of decomposition and the PBI of a body. Key Words: forensic science, ground penetrating radar, soil texture, buried remains, fatty acids, gas chromatography-mass spectrometry (GC-MS), infrared spectroscopy

Lowe, Amanda C.

56

Survival of two enterobacteria in feces buried in soil under field conditions.  

PubMed Central

Feces samples, inoculated with 10(6) Escherichia coli resistant to streptomycin and nalidixic acid and with 10(5) Salmonella typhimurium per g, were buried at five mountain field sites ranging from 2,005 to 2,730 m in elevation. Counts of each bacterium rose initially and then declined to 10(3) or 10(4) per g of feces in 8 weeks. The survival pattern was similar at all sites regardless of marked differences in elevation, soil, moisture, exposure, and vegetation. S. typhimurium numbers were consistently higher than E. coli numbers after week 3. The test encompassed most of the time that the area is snow-free and accessible for hiking. The results were judged to discredit the recommendation for shallow burial of feces and to indicate a potential health hazard under intensive use.

Temple, K L; Camper, A K; McFeters, G A

1980-01-01

57

Improving evaluation of the heat losses from arrays of pipes or electric cables buried in homogeneous soil  

Microsoft Academic Search

The evaluation of the heat loss from finite arrays of horizontal buried cylinders is very interesting for many practical applications. A considerable effort has been done in the field of the electrical engineering to develop methods for calculating the thermal flux from the cables system to the ground surface through the soil. Nevertheless, the modeling hypothesis currently assumed for the

R. de Lieto Vollaro; L. Fontana; A. Quintino; A. Vallati

2011-01-01

58

Fungal colonization of soil-buried plasticized polyvinyl chloride (pPVC) and the impact of incorporated biocides  

Microsoft Academic Search

Plasticized polyvinyl chloride (pPVC) with or without incorporated biocides was buried in grassland and forest soil for up to 10 months. The change with time in viable counts of fungi on the plastic surface was followed, together with the percentage capable of clearing the two plasticizers dioctyl adipate (DOA) and dioctyl phthalate (DOP). With time fungal total viable counts (TVC)

H. A. Sabev; P. S. Handley; G. D. Robson

2006-01-01

59

The Experimental Earthwork at Wareham, Dorset after 33 Years: 3. Interaction of Soil Organisms with Buried Materials  

Microsoft Academic Search

The Wareham Experimental Earthwork was constructed in 1963 in an area of heathland in the south of England with acidic sandy soils to investigate the processes that occurred early in the establishment of the archaeological record. Amongst its objectives was monitoring the changes to various archaeological materials that were buried in the earthwork. In this paper we present data on

T Lawson; D. W Hopkins; J. A Chudek; R. C Janaway; M. G Bell

2000-01-01

60

Production of CO 2 by surface and buried soils of the steppe zone under native and moistened conditions  

Microsoft Academic Search

Modern light chestnut and chestnut soils and their analogues buried under steppe kurgans in the southeastern part of the Russian\\u000a Plain were studied in order to determine the rates of the CO2 production by these soils under the native (with the natural moisture content) and moistened (60% of the total water capacity)\\u000a conditions. It was found that the rates of

T. S. Demkina; A. V. Borisov; V. A. Demkin

2010-01-01

61

The role of organic matter in controlling aluminum solubility in acidic mineral soil horizons  

NASA Astrophysics Data System (ADS)

Despite the ecological importance of potentially phytotoxic Al, its solubility control in acidic mineral soils remains unresolved. We examined the solubility of Al in mineral horizons of two acidic forest soils (Inceptisol and Spodosol) in southern Sweden using a series of batch experiments. Dissolution of Al was found to consist of a rapid solubilization of reactive solid phase Al, which quickly reached an equilibrium state, superimposed on a slow dissolution of less reactive Al-containing phases (e.g., primary Al-silicates). Titration experiments in the pH range 3.2-4.7 using an equilibration time of 5 days showed that at pH < 4.1, all suspensions were undersaturated with respect to gibbsite (Al(OH) 3; log ?K SO = 8.85 at 8° C) . Under such conditions, the Al solubility could be explained qualitatively by equilibrium complexation reactions with soil organic matter. Quantitatively, our results could be reproduced reasonably well using the mechanistic model WHAM, which describes the binding of Al by humic substances in organic soils. This suggests that the pool of organically bound soil Al controls the Al solubility in suspensions of strongly acidic soils. Due to the kinetically constrained release of Al from primary and secondary minerals, the amount of organically bound Al, and therefore the Al solubility in the suspensions, gradually increases with time. Consequently, a quantitative evaluation of Al solubility data from long-term batch experiments should consider both equilibrium and kinetic processes.

Berggren, Dan; Mulder, Jan

1995-10-01

62

Laboratory investigations of groundwater interactions with buried radioactive sodium wastes and attendant release and migration of tritium in adjacent soil  

SciTech Connect

Shallow land burial of sodium-bearing low-level wastes requires an assessment of safety consequences relating to (1) groundwater interactions with the residual sodium in the event of a breach of containment and (2) release of tritium dissolved in sodium along with hydrogen (both of which will permeate through adjacent soil). This paper describes the tests and evaluations being performed to establish a data base on safety consequences of burying low-level radioactive sodium wastes (RSW). This data base can be used in establishing the amounts of sodium that may be tolerated in burying RSW and in establishing related criteria.

Subbaraman, G. (Rockwell International, Canoga Park, CA); Steele, O.P. III; Witbeck, L.C.; Abrams, C.S.

1983-01-01

63

Impact of spruce forest and grass vegetation cover on soil micromorphology and hydraulic properties of organic matter horizon  

Microsoft Academic Search

Two organic matter horizons developed under a spruce forest and grass vegetation were chosen to demonstrate the impact of\\u000a a different vegetation cover on the micromorphology, porous system and hydraulic properties of surface soils. Micromorphological\\u000a studies showed that the decomposed organic material in the organic matter horizon under the grass vegetation was more compact\\u000a compared to the decomposed organic material

Radka Kodešová; Lenka Pavl?; Vít Kodeš; Anna Žigová; Antonín Nikodem

2007-01-01

64

Thaw Characteristics of Soil around Buried Pipeline in Permafrost Regions Based on Numerical Simulation of Temperature Fields  

NASA Astrophysics Data System (ADS)

The freezing-thawing processes of the soil around the buried oil and gas pipelines in permafrost regions due to the effect of the pipe and atmospheric environment may bring about dangers to the pipelines as frost heave and thaw settlement occur and go on, and then the buried pipes may face huge challenges for safe operation. To analyze the thermal effect of the buried pipe on the surrounding soil, a two-dimensional computational model of the soil temperature fields was established based on the process of the heat transfer with phase change in the soil. The temperature fields and the thaw characteristics of the soil around the operating pipeline in permafrost regions were studied using numerical methods via the software FLUENT in this paper. The developments of the maximum thawed cylinders and corresponding thaw depths under the pipeline within operation life cycle were predicted and analyzed for various medium temperatures, water contents of soils, insulation layer thicknesses and imposed boundary conditions by climatic warming. In addition, the maximum thaw settlement of the soil under the pipeline in 5 typical permafrost areas along the Russia — China oil pipeline (the section in China) within operation life cycle was calculated. The medium temperatures were assumed to be constant and sinusoidal. The results indicated that the maximum thaw depths and thawed cylinders around the pipeline in permafrost regions enlarged with time elapse and the decrease in water content of the soils under the same boundary conditions. The maximum thaw depths and thawed cylinders increased with the increase of medium temperatures after the same operation time. The insulation layer weakened heat exchange between the pipeline and the surrounding soils and thus reduced the development of the thawed cylinders effectively during the early operation period. This research may provide an effective method for engineering application, and the results may provide references for predicting the thaw settlement of the soil and pipeline in permafrost regions.

Fu, Zaiguo; Yu, Bo; Zhu, Jie; Li, Wang

65

A disconnect between O horizon and mineral soil carbon - implications for soil C sequestration  

Microsoft Academic Search

Changing inputs of carbon to soil is one means of potentially increasing carbon sequestration in soils for the purpose of mitigating projected increases in atmospheric CO2 concentrations. The effect of manipulations of aboveground carbon input on soil carbon storage was tested in a temperate, deciduous forest in east Tennessee, USA. A 4.5-year experiment included exclusion of aboveground litterfall and supplemental

Charles T. Garten Jr.

2009-01-01

66

Using Magnetic Remanence Parameters to Reconstruct Past Precipitation From Buried Soils.  

NASA Astrophysics Data System (ADS)

Magnetic measurements that rely on the comparisons between magnetically enhanced paleosols and their unaltered parent materials have long been used to quantify magnetic enhancement and to reconstruct past climatic conditions. We present measurements of magnetic remanence parameters (ARM/IRM, magnetic coercivity distributions) which, for many sites, allow for the direct quantification of pedogenically produced magnetite and estimates of past climatic conditions. Since our method does not rely on comparisons between magnetically enhanced soil horizons and their presumably unaltered parent material, this method might be especially suited for the analysis of thin loess-paleosol sequences, where pedogenically unaltered loess is absent. To test our method we analyzed the Brady soil in several locations in eastern Colorado, southwestern Nebraska and northwestern Kansas. Our analyses yielded mean annual precipitation values of 450 mm/a (Wauneta, 40.4983 ° N, -101.404 ° W), 550 mm/a (Devil's Den, 41.4561 ° N, -100.192 ° W) and 575 mm/a (Harlan County Lake, 40.0709 ° N, -99.2737 ° W), which is slightly lower than present-day precipitation at these sites and correlates well with isotope-derived reconstructions of paleoprecipitation. These quantitative reconstructions should be considered minimum estimates of paleoprecipitation as the method assumes a relatively rapid formation of the magnetic signal and no significant alteration of the magnetic phase after burial.

Geiss, C. E.; Shakya, P.; Quinton, E.; Johnson, W. C.; Mason, J.

2008-12-01

67

Structural properties of dissolved organic carbon in deep soil horizons of an arable and temporarily grassland.  

NASA Astrophysics Data System (ADS)

It is commonly accepted that dissolved organic carbon (DOC) is the bio-available fraction of the largest amount of soil organic matter (SOM), even if it does represent only a very small proportion. Because most of the studies on DOC dynamics were mainly restricted to forest soils, studies on the factors governing the dynamics of DOC in deep soil horizons (>1 m) in arable system are still very little limited. The objective of this work is to better define the proportion of DOC in deep soil horizons and indicate their main characteristics and structural properties. The study was conducted on the long term observatory for environmental research- biogeochemical cycles and biodiversity Lusignan site). DOC collected using lysimeters plates inserted to a depth of 105 cm was fractionated into 3 fractions using the two column array of XAD-8 and XAD-4 resins. The HPO (hydrophobic) fraction (i.e. humic substances) isolated from the XAD-8 resin, the TPH (Transphilic) fraction from the XAD-4 resin and the HPI (hydrophilic) fraction which corresponds to the DOC that does not adsorbed onto the two resins under the acid condition used (pH 2). DOM adsorbed onto the resins is recovered with a 75%/25% acetonitrile/water mixture and lyophilized. Depend on the amount of material; the chemical composition of DOC was performed using UV254 nm, fluorescence EEM, NMR and HPSEC/UV/COD. The results show that the concentration and structural properties of DOC in deep soil horizon were similar to those of groundwater (low SUVA (1.2 m-1.L.mg C-1), structures composed mainly of low molecular weight). Because of the relatively recent establishment of the treatment, the monitoring of the dynamics of the DOC concentrations did not show significant differences between arable and grassland. However, the temporal dynamic shows a slight increase in the DOC content regardless of the of land use. DOC concentrations between winter and the middle of spring tend to double going from 1 to 2.5 mg / L and then to 4-5 mg / L in summer time. The structural analysis reveals significant input of terpenoid derived organic matter was confirmed in the HPO fraction of DOC a results supported by the data of 13C NMR, Infra Red and Micro Scale Sealed Vessel / pyrolysis GC / MS. The chromatographic profiles obtained by flash pyrolysis GC / MS highlight the presence of phenol and alkyl phenols, generally attributed to structures polyhydroxyaromatiques (lignin / tannins), but acetamide, pyrolysis product of amino sugars constituents of the wall microbial cells. The thermochimiolyse (TMAH) / GC / MS confirmed the presence of hydroxy aromatic structures in the extracts, however, their precise origin (lignin, tannins ...) remains uncertain. The results so far indicate that the DOC in deep soil horizons is marked by low aromaticity and dominated by small size molecules. This would consist of carbon derived from terpenoids, lignin degraded and amino sugars.

Lavaud, A.; Chabbi, A.; Croue, J. P.

2009-04-01

68

Soil degradation in Central North Cameroon: Water-dispersible clay in relation to surface charge in Oxisol A and B horizons  

Microsoft Academic Search

Water dispersible clay (WDC) is a good indicator for the risk of soil erosion by water. In this study, samples from the A and B horizons of Oxisols have been collected along a toposequence developed on basalt in Central North Cameroon. The aim was to determine the WDC of these horizons and to investigate the relation with soil physical and

Jean Pierre Nguetnkam; Stefan Dultz

2011-01-01

69

Ectomycorrhizal-Dominated Boreal and Tropical Forests Have Distinct Fungal Communities, but Analogous Spatial Patterns across Soil Horizons  

PubMed Central

Fungi regulate key nutrient cycling processes in many forest ecosystems, but their diversity and distribution within and across ecosystems are poorly understood. Here, we examine the spatial distribution of fungi across a boreal and tropical ecosystem, focusing on ectomycorrhizal fungi. We analyzed fungal community composition across litter (organic horizons) and underlying soil horizons (0–20 cm) using 454 pyrosequencing and clone library sequencing. In both forests, we found significant clustering of fungal communities by site and soil horizons with analogous patterns detected by both sequencing technologies. Free-living saprotrophic fungi dominated the recently-shed leaf litter and ectomycorrhizal fungi dominated the underlying soil horizons. This vertical pattern of fungal segregation has also been found in temperate and European boreal forests, suggesting that these results apply broadly to ectomycorrhizal-dominated systems, including tropical rain forests. Since ectomycorrhizal and free-living saprotrophic fungi have different influences on soil carbon and nitrogen dynamics, information on the spatial distribution of these functional groups will improve our understanding of forest nutrient cycling.

McGuire, Krista L.; Allison, Steven D.; Fierer, Noah; Treseder, Kathleen K.

2013-01-01

70

Premining evaluation of forage grass growth on mine soil materials from an east-central Texas lignite site: 2. soil profile horizons  

Microsoft Academic Search

Several warm-season forage grasses and a cool-season pasture mix of oats plus clover were grown in a greenhouse on mixtures of soil profile horizon materials from an unmined lignite site in east-central Texas and then evaluated as to the suitability of the various soil materials for selective placement over regraded lignite mine spoil during land reclamation. Mixtures of the clayey

F. W. CHICHESTER

1983-01-01

71

Vertical distribution of an ectomycorrhizal community in upper soil horizons of a young Norway spruce (Picea abies [L.] Karst.) stand of the Bavarian Limestone Alps.  

PubMed

The vertical niche differentiation of genera of ectomycorrhiza (ECM) was assessed in a 17-year-old Norway spruce (Picea abies [L.] Karst.) plantation on a mountainous dolomitic site (1,050 m above sea level) of the Bavarian Limestone Alps. We determined ECM anatomotypes, recorded the abundance of corresponding ECM root tips and classified them into groups of ECM exploration types, which refer to the organisation and the extent of their extramatrical mycelia. The abundance of ECM was highest in the organic soil layers, compared to the mineral soil horizon. The ordination of the ECM communities and of the exploration types revealed segregation related to soil horizon properties. While Cenococcum geophilum preferred the organic soil layers, Lactarius spp., Tomentella spp. and Craterellus tubaeformis were generally most abundant in the mineral soil horizons. Cenococcum geophilum was the predominant species, possibly based on enhanced competitiveness under the prevailing site conditions. The short-distance exploration types (e.g. C. geophilum) preferentially colonised the organic soil layer, whereas the contact types (e.g. most of the Tomentella spp., C. tubaeformis) together with medium-distance types (e.g. Amphinema byssoides) were primarily associated with the underlying A-horizons. Therefore, the soil horizons had an important effect on the distribution of ECM and on their community structure. The spatial niche differentiation of ECM genera and exploration types is discussed in regard to specific physico-chemical properties of soil horizon and the assumed ecophysiological strategies of ECM. PMID:16518613

Baier, Roland; Ingenhaag, Jan; Blaschke, Helmut; Göttlein, Axel; Agerer, Reinhard

2006-02-22

72

Buried stone lines in deserts - What can they tell us about landscape evolution?  

NASA Astrophysics Data System (ADS)

Stone pavements are typical features of climate-sensitive arid environments. They allow formation of cumulic soils, protected from erosion, which may be used as archives that recorded past geomorphologic and pedologic processes. Stone lines within the soil column resulted from buried stone pavements. These stone lines, situated between compound soil horizons were affected by postdepositional processes that may be attributed to specific palaeoenvironmental conditions. From Cima Volcanic Field, eastern Mojave Desert, California, we present detailed alignment measurements of buried stone stratae. Soils in the study area were developed on basalt flows of middle Pleistocene age and consist mainly of aeolian dust which was overprinted by several phases of soil formation and stone pavement development. Stones that were arranged in specific depth intervals between compound soil horizons showed prominent orientation patterns that may be attributed to geomorphic processes that created, distorted or reworked at least two ancient stone pavements, now covered by sediment and the modern pavement. We suggest fluvial (re-)orientation of surficial stones prior to burial. Furthermore, a lateral displacement of clasts within the sediment matrix is recorded. The stratigraphic position of realigned stone lines within soil horizons presumably formed, both, under humid and arid environmental conditions allows the description of geomorphic processes for discrete climatic frameworks. Buried stone pavements are thus a unique opportunity for investigating past landscape dynamics, not recorded in other archives.

Dietze, M.; Kleber, A.

2009-04-01

73

Acceleration of organic matter decomposition after the input of available substrate in subsoil horizons  

NASA Astrophysics Data System (ADS)

Input of available substrates to soil can alter microbial activity resulting in accelerated turnover of native soil organic matter (SOM), i.e. cause priming effects (PE). Following to Fountaine et al. (2007) we hypothesized that the stability of SOM in deep soil horizons is due to the lack of input of fresh organic substrates. We also hypothesized greater PE in mineral versus organic soil horizons. These hypotheses were checked by the comparison of priming effects induced by 14C-glucose in organic and mineral horizons of modern as well as of paleo-soils (podzol sandy soil Yamalo-Nenezky region, Tumen). The following variables were determined in 50-days incubation experiment: 1) dynamics of CO2 evolution; 2) 14CO2 originated from the added glucose; 3) microbial biomass C by substrate-induced respiration; 4) activities of extracellular enzymes (?-glucosidase, chitinase, cellobiogidrolase and xylanase) with fluorogenically labeled substrates. Maximal intensity of SOM mineralization as well as of enzyme activities was observed at 2 -7 days after glucose application. The absolute values of PE were 10 times greater in modern as compared with buried horizons of paleo-soils. However, the relative increase in carbon mineralization (as compared with control soil without glucose amendment) was greater in buried than in modern soils, especially in mineral soil horizons. In organic horizons the PE amounted for 20 and 50 % of untreated control in modern and in paleo-soils, respectively. In mineral horizons the PE amount (in % of control) reached 60 % for modern and 250 % for paleo-soils. We conclude that the input of fresh organic matter in paleo-soils as well as in deep soil horizons can induce greater PE as compared with topsoil layers. This conclusion was further confirmed by the increased activity of hydrolytic enzymes during PE in modern and in buried soils. Reference: Fontaine S, Barot S, Barre P, Bdioui N, Mary B, Rumpel C (2007) Stability of organic carbon in deep soil layers controlled by fresh carbon supply. Nature 450:277-280

Blagodatskaya, Evgenia; Zhuravleva, Anna; Blagodatsky, Sergey; Yakimov, Artem; Demkin, Vitaly; Kuzyakov, Yakov

2010-05-01

74

The structural state of buried and surface soils of solonetzic complexes in the dry steppe zone of the Lower Volga basin  

NASA Astrophysics Data System (ADS)

The structural state of modern (surface) soils and the soils buried under Anna Ioannovna's rampart (1718-1720) was studied. These soils are the components of solonetzic soil complexes in the southern Privolzhskaya Upland. The dehumification and the high content of calcium in the exchange complex determine the state of the macrostructure of the chestnut soil buried about 300 years ago. The dehumification drastically lowers the water stability of the soil aggregates, and the predominance of calcium ions in the soil exchange complex prevents the destruction of the chestnut paleosol aggregates and preserves their aggregate state upon moistening. For the last 300 years, no significant changes in the macrostructure of the solonetzes have been observed.

Zolotareva, B. N.; Bukhonov, A. V.; Demkin, V. A.

2012-07-01

75

Structural properties of dissolved organic carbon in deep horizons of an arable soil.  

NASA Astrophysics Data System (ADS)

The objective of this work is to quantity the DOC that percolates in deep horizons of an arable soil, and to characterize the structural properties of the main fractions. The study was conducted on the long term observatory for environmental research- biogeochemical cycles and biodiversity Lusignan site-France. DOC collected using lysimeter plates inserted to a depth of 105 cm was fractionated into 3 fractions using the two column array of XAD-8 and XAD-4 resins. The HPO (hydrophobic) fraction (i.e. humic substances) isolated from the XAD-8 resin, the TPH (Transphilic) fraction from the XAD-4 resin and the HPI (hydrophilic) fraction which corresponds to the DOC that does not adsorbed onto the two resins under the acid condition used (pH 2). DOM adsorbed onto the resins is recovered with a 75%/25% acetonitrile/water mixture and lyophilized. The hydrophilic fraction is purified according the protocol proposed by Aiken and Leenheer (1993). The isolated fractions were subjected to several characterization tools: UV/Vis, fluorescence EEM, HPSEC/UV/DOC, 13C NMR, 14C dating, FT-IR, pyrolysis, thermochemolysis and MSSV GC/MS. The DOC content ranged from 1 to 2.5 mg / L between winter and the middle of spring and then to 4-5 mg / L in summer time. For all isolated fractions HPSEC analyses indicated the predominance of low molecular structures with a low aromatic character. Fluorescence EEM confirmed the non-humic character of the DOM. 13C-NMR spectra showed that the aromatic character decreased from HPO to TPH, and HPI character. Molecular size follows the same trend. HPI DOM was found to be strongly enriched in carboxyl groups. The 14C concentration of the HPO fraction corresponds to an apparent calibrated age around AD 1500. For the same fraction isolated from the 0 - 30 cm horizon, the measured 14C concentration 131.9 pMC corresponds to that in the atmosphere around AD 1978. Significant input of terpenoid derived organic matter was confirmed in the HPO fraction of DOC, results supported by the data of 13C NMR, FT-IR and Micro Scale Sealed Vessel / pyrolysis GC / MS. Flash pyrolysis GC / MS chromatogram highlight the presence of phenol and alkyl phenols, generally attributed to structures polyhydroxyaromatic structures. Acetamide, a pyrolysis product of amino sugars constituents of microbial cell wall is also significantly present. The thermochimiolysis (TMAH)/GC/ MS confirmed the presence of hydroxy aromatic structures in the extracts; however, their precise origin (lignin, tannins ...) remains uncertain.

Lavaud, A.; Croué, Jp; Berwick, L.; Steffens, M.; Chabbi, A.

2010-05-01

76

Thermal analysis of underground electrical power cables buried in non-homogeneous soils  

Microsoft Academic Search

A numerical study based on a control-volume formulation of the finite-difference method is performed to determine the thermal resistance existing between an underground electrical power cable and the ground surface, assuming that the filling of the rectangular trench where the cable is buried consists of two superimposed horizontal layers of different materials, stacked above the cable bedding. A large number

Roberto de Lieto Vollaro; Lucia Fontana; Andrea Vallati

2011-01-01

77

Adsorption coefficients for TNT on soil and clay minerals  

Microsoft Academic Search

To understand the fate and transport mechanisms of TNT from buried landmines is it essential to determine the adsorption process of TNT on soil and clay minerals. In this research, soil samples from horizons Ap and A from Jobos Series at Isabela, Puerto Rico were studied. The clay fractions were separated from the other soil components by centrifugation. Using the

Rosángela Rivera; Julissa Pabón; Omarie Pérez; Miguel A. Muñoz; Nairmen Mina

2007-01-01

78

Effects of Future Warming and Fire Regime Change on Boreal Soil Organic Horizons and Permafrost Dynamics in Interior Alaska  

NASA Astrophysics Data System (ADS)

There is evidence that ongoing climate change is affecting fire frequency, extent, and severity in the interior boreal region of Alaska, and these changes are likely to continue into the future. In this study we couple a landscape fire dynamics model with an ecosystem model in an application to evaluate the long term effects of changes in climate and fire regime on soil organic horizons and permafrost dynamics in interior Alaska. Changes in fire regime were simulated by the Alaska Frame-based Ecosystem Code (ALFRESCO) model driven by downscaled GCM climate outputs from CCCMA-CGCM3.1 and MPI ECHAM5 models using the A1B scenario at 1km x 1 km resolution for the Yukon River Basin in Alaska. The outputs of ALFRESCO were used to drive the dynamic organic soil version of the Terrestrial Ecosystem Model (DOS-TEM). ALFRESCO simulated fire activity would be enhanced through the middle of the 21st Century, after which fire activity would revert to pre-1990 levels because of a shift in forest composition (i.e., fuels) to a greater fraction of deciduous forest. The model framework estimated that the fibrous organic horizon would lose C through the middle of the 21st Century for the warmer ECHAM5 scenario, but would gain C throughout the 21st Century for the CCCMA scenario. The amorphous organic horizon lost C through the 21st Century for both scenarios. The active layer deepened across the basin from about 1 m to between 1.6 and 1.8 m by the middle of the century and then returned to current depth by the end of the 21st Century. These results suggest that it is important to couple changes in the soil organic horizons of boreal ecosystems to permafrost dynamics in order to fully understand the effects of changes in climate and fire regime on regional boreal ecosystem C storage.

Yuan, F.; McGuire, A. D.; Yi, S.; Euskirchen, E. S.; Rupp, T. S.; Breen, A. L.; Kurkowski, T.; Kasischke, E. S.; Harden, J. W.

2011-12-01

79

Reconnaissance of soil gas composition over the buried fault and fracture zone in southern Taiwan  

Microsoft Academic Search

The soil-gas method is based on the principle that faults and\\/or fractures are highly permeable pathways in rock formation where gases can migrate upward from the deep crust and\\/or mantle and retain their deep-source signatures in the soil cover. This method is adopted because it can give results in short time and at low costs. In this work, soil-gas compositions

Ching-Chou Fu; Tsanyao Frank Yang; Vivek Walia; Cheng-Hong Chen

2005-01-01

80

Alluvial sediment or playas: What is the dominant source of sand and silt in desert soil vesicular A horizons, southwest USA  

NASA Astrophysics Data System (ADS)

Vesicular A (Av) soil horizons form beneath desert pavements from the accretion of aeolian sediment (dust) commonly thought to be derived primarily from desiccating pluvial lakes and playas, with contributions from ephemeral washes and alluvial fans. Particle size distributions of Av horizons are typically bimodal with primary modes of very fine silt and fine sand, suggesting that the horizon matrix is derived from multiple sources. Here we conduct detailed chemical and physical analysis of both Av horizon soil samples and potential sources of aeolian sediment to better constrain the relative contributions of dust associated with the development of Av horizons. Geochemical data from both sand (125-250 µm) and silt (2-32 µm) fractions in Av horizons and potential dust sources in the eastern Mojave Desert and western Sonora Desert, USA, point to large contributions from nearby sources including distal alluvial fans and washes, and comparably lower contributions from regional sources such as playas. The silt mode is derived from suspension transport of dust, and the fine sand mode is derived from saltating sand. The desiccation of pluvial lakes in the Mojave Desert is commonly believed to have driven episodes of aeolian activity, contributing to sand dunes and Av horizon formation. We propose that alluvial fans and washes are underappreciated as desert dust sources and that pulses of dust from late Pleistocene and Holocene alluvial fans dwarfed pulses of dust from desiccating pluvial lakes in the eastern Mojave Desert.

Sweeney, Mark R.; McDonald, Eric V.; Markley, Christopher E.

2013-03-01

81

Contribution of separate solid-phase components to the formation of the cation exchange capacity in the main genetic horizons of meadow-chestnut soils  

NASA Astrophysics Data System (ADS)

Different types of cation exchange capacity (CEC) and related chemical properties were determined in the main genetic horizons of meadow-chestnut soils in the mesodepressions at the Dzhanybek Research Station of the Institute of Forestry of the Russian Academy of Sciences. In the A horizon, the CEC is mainly due to the organic matter from the clay and coarse fractions, which provides 36% of the soil CEC, and to labile silicates and other clay minerals of the clay fraction. In the Bt horizon, the CEC is mainly provided by the labile minerals of the clay fraction and organic matter of the clay and coarse fractions. The standard soil CEC was found to be significantly higher than the sum of the exchangeable cations in the A horizon and slightly lower than the sum of the exchangeable cations in the Bt and Bca2 horizons. This difference can be related to the fact that the NH{4/+} ion, which is selectively adsorbed by clay minerals, is used as a displacing cation during the determination of the exchangeable bases, while the Ba2+ ion, which is more selectively adsorbed by organic matter, is used during the determination of the standard CEC. In all the genetic horizons, the experimentally determined value of the standard CEC almost coincides with the CEC value obtained by summing the standard CECs of the different particle-size fractions with account for their contents; hence, this parameter is additive in nature.

Shashkova, G. V.; Tolpeshta, I. I.; Sizemskaya, M. L.; Sokolova, T. A.

2009-12-01

82

Organic Matter Stabilization in Surface and Subsurface Soil Horizons: C Mineralization and Early Formation of Water-Stable Macroaggregates  

NASA Astrophysics Data System (ADS)

Fine-textured Gleysolic soils in Eastern Canada are widespread and productive. Their high silt and clay content (>80%) suggests that they may have a high C storage capacity. Recent research has shown that while the absence of tillage increases the level of macroaggregation and the amount of C stored in surface soil, incorporation of crop residues by full inversion tillage commonly practiced in Eastern Canada can increase the level of organo-mineral interaction and the amount of C retained in deeper soil layers. The objective of this experiment was to evaluate the intrinsic potential of surface and subsurface horizons of fine-textured Gleysolic soils to retain additional C input. Topsoil (0-20 cm) and subsoil (30-70 cm) samples were taken from a cultivated clayey soil profile of the Kamouraska serie located near Québec and incubated with 0, 2.5, 5.0, 10.0, 20.0, and 40.0 g C kg-1 soil of 13C-15N-labelled corn residues. Large amounts of residues were added to the soils in order to saturate SOC pools. Soils and residues were mixed and incubated under optimal temperature (25°C), water potential (-38 kPa), and nutrient (C:N = 10) conditions for 52 d. More C was lost as CO2 in the topsoil than in the subsoil for all residue-C treatment, except of the highest level (40 g C kg-1 soil). At each level of C input, the ratio of C lost to C added was lower in the subsoil than in the topsoil indicating higher C protection in the subsoil than in the topsoil, especially with lower plant C input rates. The effect of C input on macroaggregate formation and stabilization was greater in subsoil than topsoil, but both soils reach a plateau of 90% macroaggregates in the 20 g C kg-1 soil treatment. The formation of new water-stable macroaggregates was greater in the subsoil than topsoil, and was related to lower C lost through respiration. These preliminary results clearly show that the subsoil is responding differently to C additions than does the topsoil. Upcoming results on isotopic signature will give us more information on the incorporation of added-C within specific soil fractions. Moreover, the use of molecular analytical techniques to trace biomarkers within specific soil fractions could help us elucidate preferential stabilization mechanisms operating under C saturated and unsaturated conditions, and during the early C stabilization period.

Poirier, V.; Angers, D. A.; Rochette, P.; Whalen, J. K.

2009-05-01

83

Soil compensation techniques for the detection of buried metallic objects using electromagnetic sensors  

NASA Astrophysics Data System (ADS)

Magnetic soils are a major source of false positives when searching for landmines or unexploded ordnance (UXO) with electromagnetic induction sensors. In adverse areas up to 30% of identified electromagnetic (EM) anomalies are attributed to geology. The main source of the electromagnetic response is the magnetic viscosity of the ferrimagnetic minerals magnetite and maghaemite. The EM phenomena that give rise to the response of magnetically viscous soil and metal are fundamentally different. The viscosity effects of magnetic soil can be accurately modelled by assuming a ferrite relaxation with a log-uniform distribution of time constants. The EM response of a metallic target is due to eddy currents induced in the target and is a function of the target's size, shape, conductivity and magnetic susceptibility. In this presentation, we consider different soil compensation techniques for time domain and frequency domain EM data. For both types of data we exploit the EM characteristics of viscous remnantly magnetized soil. These techniques will be demonstrated with time domain and frequency domain data collected on Kaho'olawe Island, Hawaii. A frequency domain technique based on modeling a negative log-linear in-phase and constant quadrature component was found to be very effective at suppressing false-alarms due to magnetic soils.

Pasion, Leonard R.; Oldenburg, Douglas W.; Billings, Stephen D.; Sinex, David

2007-05-01

84

Laser ablation ICP-MS and traditional micromorphological techniques applied to the study of different genetic horizons in thin sections: soil genesis and trace element distribution  

NASA Astrophysics Data System (ADS)

This work focuses on an innovative methodological approach to investigate in situ chemical composition of trace and rare earth (REE) elements in discrete soil features from different soil horizons: laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) was applied to clay coatings, pedogenic matrix and skeletal parent rock fragments in thin sections, coupled with traditional pedological investigations, specially clay mineralogy and micromorphology. Analyses were performed on 80 ?m-thick sections obtained from undisturbed soil samples, which represent three reddish argillic (Bt) horizons from an Alfisol developed on late Pleistocene slope deposits and three brown organic-mineral (A) horizons from an Entisol formed on Holocene aggrading fluvial sediments in the Muravera area (southeast Sardinia, Italy). Validation of the LA-ICP-MS technique provides in situ accurate and reproducible (RSD 13-18%) analysis of low concentration trace elements in the studied soil samples (0.001-0.1 ppm). Our results showed a high reliability of this method on soil thin sections and revealed that concentrations of trace and rare earth elements in the different portions of a soil profile can be used to investigate their distribution, as a response to soil-forming processes. A general trend of increase of most trace elements from rock fragments to (both clayey and organic-rich) soil matrix, to clay coatings in argillic horizons is clearly highlighted. On this basis a prominent role of pedogenetic processes in element fractionation and distribution during weathering can be supposed. In particular, element adsorption onto reactive sites of organic matter and clay particles (and possibly Fe-oxyhydroxides) and clay illuviation appear the main pedogenetic processes able to promote element enrichment after their release from the weathering of primary minerals. As clay coatings exhibit the highest concentration of trace elements, and specifically of REEs, and represent the most mobile solid phase in the soil profile, this tool can be used as a reliable indicator of soil weathering after a preliminary assessment of illuvial clay pedofeatures. This feature is consistent with a progressively increasing time of soil development, testified by the older age of the Alfisol than the Entisol profile. Such a result is also supported by a comparison of trace element concentrations between the clay and the fine earth fractions of the bulk soil horizons performed with ICP-MS in solution, showing REE enrichment in the clays from the former soil. Moreover, trace element patterns show some discontinuous trends among soil features of different horizons, coherently with erosive and/or depositional discontinuities described in the field.

Scarciglia, Fabio; Barca, Donatella; de Rosa, Rosanna; Pulice, Iolanda; Vacca, Andrea

2010-05-01

85

Mineralization of organic-matter labile fragments in the humus-accumulative horizon of soddy-podzolic soil  

NASA Astrophysics Data System (ADS)

The mineralization rate of the 14C-labeled organic matter (OM) in the humus-accumulative AE horizon of a soddy-podzolic soil was determined in a laboratory experiment. The labeling was performed in a field experiment when microamounts of 14C-labeled glucose, glycine, and uracil were added to tree waste in sacks embedded in the upper layer of the forest litter. Samples containing 14C were taken from the AE horizon (above which the sacks with the labeled material were placed) 7 and 20 months after the beginning of the experiment. The soil samples were wetted to a water content corresponding to ˜80% of the total water capacity and placed in hermetic vessels containing vials with a periodically renewed alkali solution. The incubation was performed at room temperature for 3.5 months; the alkali solutions in the vials were replaced and titrated 12 times during this period. Mineralization curves were plotted from the amounts of carbon dioxide absorbed by a 0.3 N NaOH solution, which were calculated for each time interval; its 14C content was determined by the scintillation method. The experimental treatments also included the determination of the OM mineralization rate in material from the AE horizon pretreated with a heavy liquid or a heavy liquid and a 0.1 N NaOH solution. The differences between the mineralization rates of the labeled organic matter applied to the soil in the form of glucose, glycine, and uracil under the field conditions after the interaction for 7 and 20 months were revealed. The changes in the mineralization rate after the successive extraction of the labile organic matter with a heavy liquid and a 0.1 N NaOH solution were studied. It was shown that the transformation of the labeled low-molecular-weight organic compounds in the soil over 20 months included their strong inclusion into the humus composition, which was confirmed by the similar values of the mineralization constants of the native and 14C-labeled OM. In addition, the treatments with the heavy liquid or the heavy liquid and the NaOH solution had almost identical effects on the mineralization of the native and 14C-labeled OM. The mineralization constants of the native and 14C-labeled OM in the samples taken after 7 months of the field experiment differed significantly.

Trofimov, S. Ya.; Lazarev, A. S.; Fokin, A. D.

2012-12-01

86

Anion retention in soil: Possible application to reduce migration of buried technetium and iodine  

SciTech Connect

Before testing the performance characteristics of andisols for retention of anions in the near-field environment of Low Level Wastes (LLW) disposal facilities it is necessary to locate one or more sufficiently extensive bodies of natural soil with the highest possible natural anion exchange capacity. For this purpose we developed a rugged, portable semiquantitative field test for anion exchange capacity based on short-term sorption of iodide by soil samples. We validated the iodide sorption field test against a well established quantitative laboratory test based on anion exchange of chloride and nitrate, then carried out an initial survey of volcanic terrain in northern California using the field test.

Schulz, R.K.; Duckart, E.C. (California Univ., Berkeley, CA (United States). Dept. of Soil Science); O'Donnell, E. (Nuclear Regulatory Commission, Washington, DC (United States))

1992-12-01

87

A geophysical and biochemical investigation of buried remains in contrasting soil textures in southern Ontario  

Microsoft Academic Search

Ground penetrating radar (GPR) is a non-invasive, geophysical tool used for the detection of clandestine graves. GPR operates by detecting density differences in soil by the transmission of high frequency electromagnetic (EM) waves from an antenna. A 500 Megahertz (MHz) frequency antenna is typically used for forensic investigations, as it provides a suitable compromise between depth of penetration and sub-surface

Amanda C. Lowe

2010-01-01

88

Degradation of different polystyrene\\/thermoplastic starch blends buried in soil  

Microsoft Academic Search

Blends of PS and TPS were prepared using two different plasticizers: glycerol or buriti oil by solvent casting technique. PS\\/TPS blends were submitted to degradation by soil burial tests in perforated boxes for 6 months and later analyzed by TG and CPMAS 13C NMR. After degradation, blends with glycerol presented less stages of thermal degradation and NMR signals of minor

Daniela Schlemmer; Maria J. A. Sales; Inês S. Resck

2009-01-01

89

Soil compensation techniques for the detection of buried metallic objects using electromagnetic sensors  

Microsoft Academic Search

Magnetic soils are a major source of false positives when searching for landmines or unexploded ordnance (UXO) with electromagnetic induction sensors. In adverse areas up to 30% of identified electromagnetic (EM) anomalies are attributed to geology. The main source of the electromagnetic response is the magnetic viscosity of the ferrimagnetic minerals magnetite and maghaemite. The EM phenomena that give rise

Leonard R. Pasion; Douglas W. Oldenburg; Stephen D. Billings; David Sinex

2007-01-01

90

Effect of Dissemination of 2,4-Dichlorophenoxyacetic Acid (2,4-D) Degradation Plasmids on 2,4-D Degradation and on Bacterial Community Structure in Two Different Soil Horizons  

Microsoft Academic Search

Transfer of the 2,4-dichlorophenoxyacetic acid (2,4-D) degradation plasmids pEMT1 and pJP4 from an introduced donor strain, Pseudomonas putida UWC3, to the indigenous bacteria of two different horizons (A horizon, depth of 0 to 30 cm; B horizon, depth of 30 to 60 cm) of a 2,4-D-contaminated soil was investigated as a means of bioaugmentation. When the soil was amended with

WINNIE DEJONGHE; JOHAN GORIS; S. El Fantroussi; M. Hofte; P. De Vos; W. Verstraete; E. M. Top

2000-01-01

91

Geochemistry of a buried paleosol of Eemian age at Asklev, Denmark  

NASA Astrophysics Data System (ADS)

Buried soil surfaces are rich sources of information about past fauna, vegetation development, glacier dynamics, and climate variations However, in Denmark such former surfaces are very rare, as they rarely have escaped the intensive erosion below and in front of the Scandinavian ice sheets during the previous cold stages. Here we present a well-drained paleosol found extensively in a large gravel pit in the central part of Jutland, Denmark. The paleosol is suggested denoted the "Asklev paleosol". The Asklev paleosol is a well developed Podzol in sandy till of late Saalian age - the Asklev Till. The Asklev podsol is covered by fluvial sand in which another weaker podsol is present. Thermo-luminescense dating of the sand layer revealed an age of c. 100 ka BP, i.e. that the soil surface was buried in the early Weichelian. The surface was thus stable during the entire Eemain interglacial and subject to pedogenesis for >15.000 years. Discordantly resting on the fluvial sand is about 1.5 m of sandy till with an undisturbed grey lower part and a brown cryoturbated upper part. Fabric analyses from the lower grey part of the till reveal an ice movement from the SSE. This till is deposited during MIS 4 in middle Weichselian Thin sections from the Podzol' show that the buried A-horizons micromorphology is not fully comparable to present-day Podzols in the region as it has a well developed argillic horizon below despite the parent material low in clay (< 3%). In contrast to modern Danish Podzols it also retain ample evidence of burning (charcoal) and frost features (capping). The Asklev paleosol classify as a Placic Podzol, but is a typical bi-sequum with a Bt-horizon at depth. Its content of organic C is up to 38 mg C/g soil in the A-horizon, 8.4 mg C/g soil in the Bhs-horizon, which decreases to <1 mg C/g soil in the C-horizon. Carbon-to-nitrogen ratios range from 80 in the E-horizon to 25 in the C-horizon. Concentrations of heavy metals is low with maximums of 3.7 mg Ni/kg soil, 16.4 mg Cr/kg soil, <0.05 mg Cd/kg soil, 6.7 mg Pb/kg soil and 33 mg Cu/kg soil. Arsenic concentrations vary from <0.1 mg/kg soil in the E-horizon to 4.7 mg/kg soil in the Bt-horizon. Comparing the geochemistry of the Asklev paleosol with a modern analogue Podzol in a nearby natural, ancient woodland reveal a general higher content of heavy metals in the paleosol. These differences reflect a combination of different parent materials, modern-day pollution rates, losses/additions during the c. 90 ka where the soil has experienced permafrost, and the c. 10 ka with moist conditions during the present interglacial. The combined methods together reflect a soil surface from the previous interglacial which may act as an important reference for modern-day soil chemical status and e.g. pollution rates, especially if enough sites with the Asklev paleosol is analysed. Keywords Soil, Paleosol, heavy metal, Geochemical background concentration, Glacial stratigraphy

Kristiansen, S. M.; Dalsgaard, K.; Kronborg, C.

2009-04-01

92

Soil morphology of a debris flow chronosequence in a coniferous forest, southern California, USA  

USGS Publications Warehouse

Soils on a series of debris flow deposits, ranging from < 1 to 244??years old, were described and sampled in order to investigate the early stages of soil development. The parent material at the site is debris flow regolith, composed mainly of gneiss, the soil moisture regime is xeric, and the vegetation is mixed coniferous forest. Ages of the deposits were assessed using dendrochronology. Morphologic trends in the organic horizons included a thickening of the humus form over time, along with the development of Fm and Hr horizons. The humus forms underwent a progression from Mormodors (20??years old), to Hemimors (26-101??years old), and finally Lignomors (163??years old) and Resimors (184-244??years old). Changes in physical properties of the uppermost mineral horizons as a function of increasing age included a decrease in the volume of coarse fragments, a linear decrease in bulk density, and a darkening and reddening of the soil color. No significant soil development took place in the subsoil during the time span of this chronosequence. The soils described were classified as Typic Xerofluvents and Typic Xerorthents (Regosols and Leptosols). Buried A horizons were observed in many of the soils. Where the A horizons could be linked to dendrochronology to assess the age of the buried surface, we found that the properties of the buried A horizons do not serve as a good indicator of the age of the surface. This study suggests rapid development of the humus form profile (organic horizons and A horizon) following debris flow deposition and rapid degradation of these horizons when the debris flow surface is buried. ?? 2008 Elsevier B.V.

Turk, J. K.; Goforth, B. R.; Graham, R. C.; Kendrick, K. J.

2008-01-01

93

Estimating Depth to Argillic Soil Horizons using Apparent Electrical Conductivity Response Functions  

Technology Transfer Automated Retrieval System (TEKTRAN)

Maps of apparent electrical conductivity (ECa) of the soil profile are widely used in precision agriculture practice and research. A number of ECa sensors are commercially available, each with a unique response function (i.e., the relative contribution of soil at each depth to the integrated ECa rea...

94

SULFUR DYNAMICS IN MINERAL HORIZONS OF TWO NORTHERN HARDWOOD SOILS A COLUMN STUDY WITH 35S  

EPA Science Inventory

Sulfur dynamics of two Spodosols were ascertained using soil columns constructed from homogenized mineral soil from northern hardwood ecosystems at the Huntington Forest (HF) in the Adirondack Mountains of New York and Bear Brook Watershed in Maine (BBWM). olumns were leached for...

95

Detecting buried remains in Florida using ground-penetrating radar  

NASA Astrophysics Data System (ADS)

This research tested the applicability of using ground-penetrating radar (GPR) in Florida to detect buried bodies; and assessed the effect of body size, depth, antenna type, time, and soil type on grave detection. Furthermore, because of the emphasis on decomposition, it was possible to address the role of depth, body size, time, and soil type on decomposition. The site was located in an open pasture, where 20 pig (Sus scrofa) cadavers of two average weights (29.7 and 63.8 kg) were buried at two depths (50 to 60 or 100 to 110 cm). The cadavers were monitored monthly for durations up to 21 months with GPR using 900- and 500-MHz antennae. Two different soil types were used: one composed solely of sand horizons and one composed of sand with clay horizons at approximately 1.00 m. The graves were excavated at the termination of each monitoring period to collect soil samples and score decomposition. Overall, depth was the most significant factor controlling decomposition, followed by time. Body size and soil type were not major factors. Ground-penetrating radar can be a very effective tool for grave detection in Florida. Salient anomalies were produced for the duration of this study due to a strong enough contrast between the skeleton, or decomposing body, and the surrounding soil with that of the undisturbed soil. While cadaver size and time were not major factors in grave detection, soil type and antenna choice were. Although it was possible to detect a decomposing body and a skeleton in both shallow and deep sand graves, it was difficult to image large pig cadavers retaining extensive soft tissue buried in proximity to the clay horizon in as little as six months. The clay masked the contrast of the cadavers by reducing their relative dielectric permittivity. Pig cadaver size was not a major factor in grave detection. The imagery of the 500-MHz antenna was preferred over the higher resolution of the 900-MHz, because the increased detail may result in difficulty differentiating the cadaver anomalies from general background noise. Postprocessing of the profile was not needed unless excessive horizontal banding was noted.

Schultz, John Joseph

96

Laboratory Load Tests on Buried Flexible Pipe.  

National Technical Information Service (NTIS)

As part of a study on soil factors affecting the behavior of buried pipe, research is being conducted on the soil-structure interaction of buried flexible pipe; earlier tests dealt with rigid pipe. The main items of investigation on flexible pipe are soil...

A. K. Howard

1968-01-01

97

Early season nitrogen limitation of microbial respiration in the organic horizon of tussock tundra soils  

NASA Astrophysics Data System (ADS)

Low nitrogen (N) availability is a key constraint to decomposition of organic matter in arctic ecosystems. In tussock tundra soils, we have previously observed relatively high N availability early in the growing season followed by a crash in N availability later in the season. This crash led us to hypothesize that N is less limiting to microbial respiration early in the season and more limiting later in the season. To test this hypothesis, we incubated tussock tundra soils for one week in mason jars at three temperatures (5,10,15°C) with either ambient N levels or additional N (112.5 ug N g-1 dry soil). We made early season measurements at the beginning of June and late season measurements at the end of July in both 2010 and 2011. Contrary to our hypothesis, the laboratory incubations suggest that soil respiration is N-limited at both times of the season. The size of the limitation varied with temperature, with the most consistent effect of added N observed at 10°C. Reductions in the C:N ratio of the microbial biomass shows that they readily took up the added N in both the early and late season. We also saw that more carbon overall was respired in the warmer treatments in 2011. Rapid reductions in the respiration rate over the course of the one week incubation, particularly in 2011, suggest that labile carbon is also strongly limiting to microbial respiration in these soils. These data suggest that both carbon and nitrogen limitation to decomposition can occur very early in the growing season, even shortly after the onset of soil thaw. The results of this study reinforce the role of nutrient limitation as an important constraint on the loss of large stocks of carbon from the organic-rich upper layers of tussock tundra soils.

Darrouzet-Nardi, A.; Wallenstein, M. D.; Steltzer, H.; Sullivan, P.; Melle, C.; Segal, A. D.; Weintraub, M. N.

2011-12-01

98

Soil structure interaction analysis of buried tank subjected to vertical excitations  

SciTech Connect

Underground High Level Waste Storage Tanks are subjected to strigent seismic requirements At some DOE sites, many existing waste storage tanks are of the double-shell tank design. In this configuration, the concrete outer structure acts as the vault and provides secondary confinement for the primary steel waste storage tank. To ensure the safety of the design and a good understanding of the seismic response of the concrete confinement structure, seismic analysis, including the effects of Soil-Structure Interaction (SSI), is generally performed with special purpose SSI computer analysis programs. Generally, the seismic SSI response due to vertical excitation is considered to be secondary to those of the horizontal excitation. In this paper, a detailed evaluation of the SSI response due to vertical excitation is presented and is shown to merit equal consideration relative to the horizontal excitation. The geometry and relative dimensions (i.e. flexibility) of the structure can have significant influence on the vertical seismic SSI response in local region(s) of the concrete structure.

Wong, C.K. [ICF Kaiser Engineers, Inc., Oakland, CA (United States); Stine, M.; Wagenblast, G. [ICF Kaiser Hanford Co., Richland, WA (United States); Farnworth, S. [Westinghouse Hanford Co., Richland, WA (United States)

1995-09-01

99

IIB horizons  

NASA Astrophysics Data System (ADS)

We solve the Killing spinor equations for all near-horizon IIB geometries which preserve at least one supersymmetry. We show that generic horizon sections are eight-dimensional almost Hermitian spinc manifolds. Special cases include horizon sections with a Spin(7) structure and those for which the Killing spinor is pure. We also explain how the common sector horizons and the horizons with only 5-form flux are included in our general analysis. We investigate several special cases mainly focusing on the horizons with constant scalars admitting a pure Killing spinor and find that some of these exhibit a generalization of the 2-SCYT condition that arises in the horizons with 5-form fluxes only. We use this to construct new examples of near-horizon geometries with both 3-form and 5-form fluxes.

Gran, U.; Gutowski, J.; Papadopoulos, G.

2013-10-01

100

Non-cellulosic neutral sugar contribution to mineral associated organic matter in top- and subsoil horizons of two acid forest soils  

NASA Astrophysics Data System (ADS)

It is generally accepted now that chemically recalcitrant plant-derived molecules, such as lignin, are not preserved in high amounts in soil for more than a few decades. In contrast, labile polysaccharides may be stabilised in greater proportions and for longer timescales probably due to their ability to interact with the mineral phase. The aim of the study was to investigated sugar composition of density fractions of a whole soil profile and to related total sugar content and composition to 14C age of SOM. We investigated the polysaccharide composition of bulk soil and mineral-bound (density fractions > 2g cm-3) organic matter in topsoil and subsoil horizons of a Podzol and a Cambisol. Our results showed that total sugar contents were generally higher in the Cambisol than in the Podzol. For most horizons of both soils, the sugars were enriched in the mineral-bound organic matter fraction. This fraction showed a monosaccharide distribution typical for microbial sugars, whereas in bulk soil horizons higher contributions of plant-derived sugars were observed. A strong relationship with the 14C activity of the dense fraction suggests that microbial-derived polysaccharides are most likely stabilized preferentially by mineral interactions compared to plant-derived polysaccharides.

Rumpel, Cornelia; Eusterhues, Karin; Kögel-Knabner, Ingrid

2010-05-01

101

Buried Bones  

NSDL National Science Digital Library

This site contains an activity in which students create make-believe dig sites by burying chicken bones in plaster of Paris. Then they try to excavate the "fossils." Students discover that fossilized bones are usually very delicate and deeply buried in rocks. Removing them in a lab takes skill, patience, and the right tools. This activity may be done at school or at home with a friend and adult supervision.

102

Wavenumber prediction and measurement of axisymmetric waves in buried fluid-filled pipes: Inclusion of shear coupling at a lubricated pipe/soil interface  

NASA Astrophysics Data System (ADS)

Acoustic methods have been widely used to detect water leaks in buried fluid-filled pipes, and these technologies also have the potential to locate buried pipes and cables. Relatively predictable for metal pipes, there is considerably more uncertainty with plastic pipes, as the wave propagation behaviour becomes highly coupled between the pipe wall, the contained fluid and surrounding medium. Based on the fully three-dimensional effect of the surrounding soil, pipe equations for n=0 axisymmetric wave motion are derived for a buried, fluid-filled pipe. The characteristics of propagation and attenuation are analysed for two n=0 waves, the s=1 wave and s=2 wave, which correspond to a predominantly fluid-borne wave and a compressional wave predominantly in the shell, respectively. At the pipe/soil interface, two extreme cases may be considered in order to investigate the effects of shear coupling: the "slip" condition representing lubricated contact; and the "no slip" condition representing compact contact. Here, the "slip" case is considered, for which, at low frequencies, analytical expressions can be derived for the two wavenumbers, corresponding to the s=1 and s=2 waves. These are both then compared with the situations in which there is no surrounding soil and in which the pipe is surrounded by fluid only, which cannot support shear. It is found that the predominant effect of shear at the pipe/soil interface is to add stiffness along with damping due to radiation. For the fluid-dominated wave, this causes the wavespeed to increase and increases the wave attenuation. For the shell-dominated wave there is little effect on the wavespeed but a marked increase in wave attenuation. Comparison with experimental measurements confirms the theoretical findings.

Muggleton, J. M.; Yan, J.

2013-03-01

103

Modeling Overland Flow Contamination by Chemicals Mixed in Shallow Soil Horizons Under Variable Source Area Hydrology  

NASA Astrophysics Data System (ADS)

Agricultural chemicals (fertilizers, nutrients, pesticides, etc.) are frequently mixed into the shallow soil layers so that they may be leached down during water applications (rainfall/irrigation). These events often generate overland flows which cause the release and migration of these chemicals into surface waters. In many such applications, overland flow does not immediately develop as a sheet over the whole plane, but gradually increases in extent in accordance with the variable source area (VSA) concept. This paper deals with the modeling of surface contamination under such circumstances. Results were obtained for a single hypothetical agricultural plot. Some comparisons were made regarding the relative amounts of solute lost to overland flow and to those leached into the soil as a function of time.

Govindaraju, Rao S.

1996-03-01

104

New Observations on the Interactions Between Evidence and the Upper Horizons of the Soil  

Microsoft Academic Search

Since Darwin's work on the movement of objects in the soil due to earthworm action, interest has continued in determining\\u000a how bioturbation affects the archaeological record. The work of Darwin is being continued with an additional focus on forensic\\u000a implications of evidence moving over time. The actions of earthworms and the rates at which they cause small objects to sink

Ian Hanson; Jessica Djohari; Jennifer Orr; Patricia Furphy; Claire Hodgson; Georgina Cox; Gemma Broadbridge

105

AFM Observations of Weathering and Microbiological Alterations on the Surface of Calcite Buried in Arctic Soil (Spitsbergen)  

NASA Astrophysics Data System (ADS)

This study focused on the direct observation of chemical weathering and biological activity on mineral surfaces in the newly forming arctic soil of West Spitsbergen . Chemical weathering and soil forming processes associated with glaciers may affect several geochemical cycles including global carbon cycle and as a result have negative feedbacks on the global climate. Study areas are the foreland of the Werenskiold glacier, continuously retreating by several meters a year. Several samples of freshly cleaved calcite had been buried in the soils for one year. Samples were analyzed with the use of Atomic Force Microscopy (AFM). Results of AFM investigation show changes observed on a calcite samples located respectively about 2500 meters (sample calcite 1) and 100 m (sample calcite 2) from the glacier front as compared to a control sample calcite 0, that has never been exposed to glacier environment. Samples calcite 1 and calcite 2 were recovered from Spitsbergen after 1 year. Compared to the control sample calcite 0, which displays sharp edges and smooth surfaces, both field-treated samples calcite 1 and calcite 2 display rounded edges, irregular surfaces, numerous dissolution features and rounded pitches associated with bacterial activities. The observations suggest that both samples calcite 1 and 2 undergo intensive and rapid chemical and biological weathering when exposed to relatively unsaturated with respect to calcite glacial meltwaters. Several types of analyses have been applied to various regions and lines on the calcite surface. Selected regions on the calcite surface included (a) the entire area of the observed surface (b) top step region roughness, and (c) bottom step region roughness. Selected line parameters have been calculated along: (a) three randomly selected parallel lines, (b) top step line roughness, and (c) bottom step line roughness. Both surface area roughness and line roughness are calculated as the mean deviation of the height. Significant differences have been observed between the samples in calculated roughness parameters, with increase of these parameters ranging from 28% to 241% in calcite 1 located 2500 m from the glacier front and from 100% to 486% in calcite 2 located 100m from the glacier front, as compared to calcite 0. Roughness of the entire surface area for the control calcite 0 was 5.73nm, which increased by 28% in calcite 1 and by 100% in calcite 2. Top step edge roughness increases from calcite 0 (1.82 nm) by 241% to 6.2 nm in calcite 1 and by 486% to 8.84 nm in calcite 2. Bottom step edge roughness increases from 2.08 in calcite 0 by 98% to 4.52nm in calcite 1 and by 149% to 5.67 nm in calcite 2. Line roughness for calcite 0 is 3.26, which increased by 102% in calcite 1 and by 217% in calcite 2. Top step line roughness increases from 2.04 nm in calcite 0 by 191 % to 5.93 nm in calcite 1 and by 276% to 7.67nm in calcite 2. Bottom step line roughness increases from 2.28 nm in calcite 0 by 198% to 4.52 nm in calcite 1and by 249% to 5.67 nm in calcite 2. In calcite 0

Summers, S.; Matyjasik, M.; Inglefield, C.; Manecki, M.; Plonka, A.; Paget, C.; Park, C.

2008-12-01

106

Preliminary systems design study assessment report. [Evaluation of using specific technologies and system concepts for testing the buried waste and the surrounding contaminated soil  

SciTech Connect

The System Design Study (SDS), part of the Waste Technology Development Department at the Idaho National Engineering Laboratory (INEL), examined techniques available for the remediation of hazardous and transuranic waste stored at the Radioactive Waste Management Complex's Subsurface Disposal Area at the INEL. Using specific technologies, system concepts for treating the buried waste and the surrounding contaminated soil were evaluated. Evaluation included implementability, effectiveness, and cost. The SDS resulted in the development of technology requirements including demonstration, testing, and evaluation activities needed for implementing each concept.

Mayberry, J.L. (EG and G Idaho, Inc., Idaho Falls, ID (United States)); Feizollahi, F. (Bechtel National, Inc., San Francisco, CA (United States)); Del Signore, J.C. (Ebasco Environmental, Richland, WA (United States))

1991-09-01

107

Comparison of elemental contents in O- and C-horizon soils from the surroundings of Nikel, Kola Peninsula, using different grain size fractions and extractions  

Microsoft Academic Search

Forty-five soil samples from the O- and C-horizons were taken in a 12,000 km2 area on the borders of Finland, Norway and Russia. The nickel smelter at Nikel, the ore roasting plant at Zapoljarnij, both in Russia, and the iron ore mine and processing plant at Kirkenes in Norway, are all situated within this area. Element levels and variation in

Clemens Reimann; Patrice de Caritat; Heikki Niskavaara; Tor Erik Finne; Galina Kashulina; Vladimir A Pavlov

1998-01-01

108

Laboratory Load Tests on Buried Flexible Pipe.  

National Technical Information Service (NTIS)

In an effort to lower construction costs of closed conduit systems, the Bureau of Reclamation has been investigating the soil-structure interaction of buried flexible pipe. The test pipes are buried in a large container by placing a lean clay soil at opti...

A. K. Howard

1970-01-01

109

Soil Taxonomy and Soil Properties.  

National Technical Information Service (NTIS)

The 16 papers in this report deal with the following areas: soil taxonomy; an overview; diagnostic soil horizons in soil taxonomy; soil moisture and temperature regimes in soil taxonomy; particle size and mineralogy in soil taxonomy; soil series and soil ...

1977-01-01

110

Buried Bones  

NSDL National Science Digital Library

In this activity, pairs of learners will create two make-believe dig sites by burying chicken bones in plaster of Paris--a powder that hardens when wet. Then, learners try to excavate (dig out) their partner's "fossils." Learners will discover that excavating fossils requires skill, patience, and the right tools. Note: this activity requires adult supervision as working with plaster of Paris can be dangerous if not done properly.

History, American M.

2012-06-26

111

Soils  

NSDL National Science Digital Library

The purpose of the handout is to identify the three major types of soils: pedalfer, pedocal, and laterite, and to understand the soil profile. This is accomplished with brief descriptions of the soil horizons and the designation of common elements to pedalfers, pedocals, and laterite soils. The handout is concluded with a discussion of soil erosion. Links are provided to the online Physical Geology resources at Georgia Perimeter College.

Gore, Pamela

1995-08-29

112

HORIZON SENSING  

SciTech Connect

Real-time horizon sensing (HS) on continuous mining (CM) machines is becoming an industry tool. Installation and testing of production-grade HS systems has been ongoing this quarter at Oxbow Mining Company, Monterey Coal Company (EXXON), FMC Trona, Twentymile Coal Company (RAG America), and SASOL Coal. Detailed monitoring of system function, user experience, and mining benefits is ongoing. All horizon sensor components have finished MSHA (United States) and IEC (International) certification.

Larry G. Stolarczyk, Sc.D.

2002-07-31

113

HORIZON SENSING  

Microsoft Academic Search

With the aid of a DOE grant (No. DE-FC26-01NT41050), Stolar Research Corporation (Stolar) developed the Horizon Sensor (HS) to distinguish between the different layers of a coal seam. Mounted on mining machine cutter drums, HS units can detect or sense the horizon between the coal seam and the roof and floor rock, providing the opportunity to accurately mine the section

Larry G. Stolarczyk

2003-01-01

114

Modeling of buried explosions  

SciTech Connect

Los Alamos National Laboratory has been and continues developing techniques for modeling buried explosions using a large geotechnical centrifuge. When fully developed, the techniques should permit the accurate modeling of large explosions in complex geometries. Our intentional application is to study the phenomena of explosive cavity formation and collapse. However, the same methods should also be applicable to simulation of bursts shallow enough to produce craters, and perhaps even of airbursts in situations where soil overburden is important. We have placed primary emphasis on test bed construction methods and on accurate measurement of the ground shock produced by the explosions. 8 refs., 7 figs.

Gaffney, E.S.; Wohletz, K.H.; House, J.W.; Brown, J.A.

1987-01-01

115

The chronological position of the Lohne Soil in the Nussloch loess section - re-evaluation for a European loess-marker horizon  

NASA Astrophysics Data System (ADS)

The loess section of Nussloch in southwestern Germany is a key profile for the reconstruction of the terrestrial palaeo-environment of central Europe at the time of the Last Glacial and Interglacial. Recently, the significance of the site for palaeo-environmental and geoarchaeological research increased additionally, with the discovery of unique Palaeolithic cultural remains from anatomically and culturally modern humans that invaded southwestern Germany during the Weichselian (Würmian) Pleniglacial period. At Nussloch, a chrono-stratigraphical key position is taken by a Middle Pleniglacial Cambisol remain which, under the designation Lohne Soil, serves as an important pedostratigraphic marker horizon for the greater area. Repeatedly, Greenland interstadial (GIS) 8 was suggested as a likely period of soil formation for the Lohne Soil. This interpretation is yet not justified on the basis of published chronometric data. Critical assessment of the data points to a later period of soil formation, likely during GIS7 to GIS5. This conclusion is supported by a new set of radiocarbon ages for the Nussloch site which are presented here for the first time. Consequences of a revised chronology for correlations of Pleniglacial Cryosols below and above the Lohne Soil with Greenland interstadials are discussed. The implications are important for European loess research as the Nussloch section serves as a reference base for loess sections throughout Europe.

Kadereit, Annette; Kind, Claus-Joachim; Wagner, Günther A.

2013-01-01

116

Accumulation of heavy metals in dietary vegetables and cultivated soil horizon in organic farming system in relation to atmospheric deposition in a seasonally dry tropical region of India.  

PubMed

Increasing consciousness about future sustainable agriculture and hazard free food production has lead organic farming to be a globally emerging alternative farm practice. We investigated the accumulation of air-borne heavy metals in edible parts of vegetables and in cultivated soil horizon in organic farming system in a low rain fall tropical region of India. The factorial design of whole experiment consisted of six vegetable crops (tomato, egg plant, spinach, amaranthus, carrot and radish) x two treatments (organic farming in open field and organic farming in glasshouse (OFG)) x seven independent harvest of each crop. The results indicated that except for Pb, atmospheric deposition of heavy metals increased consistently on time scale. Concentrations of heavy metals in cultivated soil horizon and in edible parts of open field grown vegetables increased over time and were significantly higher than those recorded in OFG plots. Increased contents of heavy metals in open field altered soil porosity, bulk density, water holding capacity, microbial biomass carbon, substrate-induced respiration, alkaline phosphatase and fluorescein diacetate hydrolytic activities. Vegetable concentrations of heavy metal appeared in the order Zn > Pb > Cu > Ni > Cd and were maximum in leaves (spinach and amaranths) followed by fruits (tomato and egg plant) and minimum in roots (carrot and radish). Multiple regression analysis indicated that the major contribution of most heavy metals to vegetable leaves was from atmosphere. For roots however, soil appeared to be equally important. The study suggests that if the present trend of atmospheric deposition is continued, it will lead to a destabilizing effect on this sustainable agricultural practice and will increase the dietary intake of toxic metals. PMID:18202901

Pandey, J; Pandey, Usha

2008-01-17

117

HORIZON SENSING  

SciTech Connect

With the aid of a DOE grant (No. DE-FC26-01NT41050), Stolar Research Corporation (Stolar) developed the Horizon Sensor (HS) to distinguish between the different layers of a coal seam. Mounted on mining machine cutter drums, HS units can detect or sense the horizon between the coal seam and the roof and floor rock, providing the opportunity to accurately mine the section of the seam most desired. HS also enables accurate cutting of minimum height if that is the operator's objective. Often when cutting is done out-of-seam, the head-positioning function facilitates a fixed mining height to minimize dilution. With this technology, miners can still be at a remote location, yet cut only the clean coal, resulting in a much more efficient overall process. The objectives of this project were to demonstrate the feasibility of horizon sensing on mining machines and demonstrate that Horizon Sensing can allow coal to be cut cleaner and more efficiently. Stolar's primary goal was to develop the Horizon Sensor (HS) into an enabling technology for full or partial automation or ''agile mining''. This technical innovation (R&D 100 Award Winner) is quickly demonstrating improvements in productivity and miner safety at several prominent coal mines in the United States. In addition, the HS system can enable the cutting of cleaner coal. Stolar has driven the HS program on the philosophy that cutting cleaner coal means burning cleaner coal. The sensor, located inches from the cutting bits, is based upon the physics principles of a Resonant Microstrip Patch Antenna (RMPA). When it is in proximity of the rock-coal interface, the RMPA impedance varies depending on the thickness of uncut coal. The impedance is measured by the computer-controlled electronics and then sent by radio waves to the mining machine. The worker at the machine can read the data via a Graphical User Interface, displaying a color-coded image of the coal being cut, and direct the machine appropriately. The Horizon Sensor program began development in 1998 and experienced three major design phases. The final version, termed HS-3, was commissioned in 2000 with the assistance of the DOE-Mining Industry of the Future program, commercialized in 2002, and has been used 14 times in 12 different mines within the United States. The Horizon Sensor has applications in both underground and surface mining operations. This technology is primarily used in the coal industry, but is also used to mine trona and potash. All horizon sensor components have Mine Safety and Health Administration (MSHA) (United States) and IEC (International) certification. Horizon Sensing saves energy by maximizing cutting efficiency, cutting only desired material. This desired material is cleaner fuel, therefore reducing pollutants to the atmosphere when burned and burning more efficiently. Extracting only desired material increases productivity by reducing or eliminating the cleaning step after extraction. Additionally, this technology allows for deeper mining, resulting in more material gained from one location. The remote sensing tool allows workers to operate the machinery away from the hazards of cutting coal, including noise, breathing dust and gases, and coal and rock splintering and outbursts. The HS program has primarily revolved around the development of the technology. However, the end goal of the program has always been the commercialization of the technology and only within the last 2 years of the program has this goal been realized. Real-time horizon sensing on mining machines is becoming an industry tool. Detailed monitoring of system function, user experience, and mining benefits is ongoing.

Larry G. Stolarczyk

2003-03-18

118

Joint application of geophysical methods and Direct Push-soil gas surveys for the improved delineation of buried fault zones  

NASA Astrophysics Data System (ADS)

This study provides an example of fault structure delineation using both geophysical measurements and soil-gas surveys. Seismic refraction and electrical resistivity tomography investigations were performed in combination with Direct Push (DP) soil gas concentration measurements, with the main objective being the characterization of an assumed permeable fault structure which is covered by sediments that are over 20 m thick. Geophysical methods were used to locate a potential fault zone and to provide an insight into the structural features of the covering sediments. Methods for quantifying the soil-gas concentration were applied to evaluate the permeability of the fault zone. The positioning of gas sampling points was based on results of a geophysical survey undertaken beforehand. Gas sampling was performed using DP-technology to obtain concentration profiles for the inert gas Radon-222 and its carrier gas CO2 along the profile at different depths. Joint interpretation of the spatial distribution of geogenic gases and results from the geophysical survey allowed us to produce a representative model image of the fault structure consisting of two fault branches. Based on this image, it was possible to interpret the observed gas concentration patterns.

Schütze, Claudia; Vienken, Thomas; Werban, Ulrike; Dietrich, Peter; Finizola, Anthony; Leven, Carsten

2012-07-01

119

Organic Matter Stabilization in Surface and Subsurface Soil Horizons: C Mineralization and Early Formation of Water-Stable Macroaggregates  

Microsoft Academic Search

Fine-textured Gleysolic soils in Eastern Canada are widespread and productive. Their high silt and clay content (>80%) suggests that they may have a high C storage capacity. Recent research has shown that while the absence of tillage increases the level of macroaggregation and the amount of C stored in surface soil, incorporation of crop residues by full inversion tillage commonly

V. Poirier; D. A. Angers; P. Rochette; J. K. Whalen

2009-01-01

120

Effects of forest clear-cutting on the sulphur, phosphorus and base cations fluxes through podzolic soil horizons  

Microsoft Academic Search

Clear-cutting considerably alters the flow of nutrients through the forest ecosystem. These changes are reflected in soil solution concentrations and fluxes. The effects of clear-cutting (stems only) on the fluxes of water soluble phosphorus (P), sulphur (S) and base cations (Ca, Mg and K) through a podzolic soil were studied in a Norway spruce dominated mixed boreal forest in eastern

Sirpa Piirainen; Leena Finér; Hannu Mannerkoski; Michael Starr

2004-01-01

121

Preliminary Systems Design Study assessment report. [Evaluation of using specific technologies, system concepts for treating the buried waste and the surrounding contaminated soil  

SciTech Connect

The System Design Study (SDS), part of the Waste Technology Development Department at the Idaho National Engineering Laboratory (INEL), examined techniques available for the remediation of hazardous and transuranic waste stored at the Radioactive Waste Management Complex's Subsurface Disposal Area at the INEL. Using specific technologies, system concepts for treating the buried waste and the surrounding contaminated soil were evaluated. Evaluation included implementability, effectiveness, and cost. The SDS resulted in the development of technology requirements including demonstration, testing, and evaluation activities needed for implementing each concept. This volume of the Systems Design Study contain four Appendixes that were part of the study. Appendix A is an EG G Idaho, Inc., report that represents a review and compilation of previous reports describing the wastes and quantities disposed in the Subsurface Disposal Area of the Idaho National Engineering Laboratory. Appendix B contains the process flowsheets considered in this study, but not selected for detailed analysis. Appendix C is a historical tabulation of radioactive waste incinerators. Appendix D lists Department of Energy facilities where cementation stabilization systems have been used.

Mayberry, J.L.; Feizollahi, F.; Del Signore, J.C.

1992-01-01

122

Preliminary Systems Design Study assessment report. [Evaluation of using specific technologies, system concepts for treating the buried waste and the surrounding contaminated soil  

SciTech Connect

The System Design Study (SDS), part of the Waste Technology Development Department at the Idaho National Engineering Laboratory (INEL), examined techniques for the remediation of hazardous and transuranic waste stored at Radioactive Waste Management Complex's Subsurface Disposal Area at the INEL. Using specific technologies, system concepts for treating the buried waste and the surrounding contaminated soil were evaluated. Evaluation included implementability, effectiveness, and cost. The SDS resulted in the development of technology requirements including demonstration, testing, and evaluation activities needed for implementing each concept. This volume contains introduction section containing a brief SDS background and lists the general assumptions and considerations used during the development of the system concepts. The introduction section is followed by sections describing two system concepts that produce a waste form in compliance with the Waste Isolation Pilot Plant (WIPP) Waste Acceptance Criteria (WAC) and transportation package (TRAMPAC) requirements. This system concept category is referred to as Waste Form 4, WIPP and TRAMPAC Acceptable.'' The following two system concepts are under this category: Sort, Treat, and Repackage System (4-BE-2); Volume Reduction and Packaging System (4-BE-4).

Mayberry, J.L.; Feizollahi, F.; Del Signore, J.C.

1992-01-01

123

Variation of MCPA, metribuzine, methyltriazine-amine and glyphosate degradation, sorption, mineralization and leaching in different soil horizons  

Microsoft Academic Search

Pesticide mineralization and sorption were determined in 75 soil samples from 15 individually drilled holes through the vadose zone along a 28km long transect of the Danish outwash plain. Mineralization of the phenoxyacetic acid herbicide MCPA was high both in topsoils and in most subsoils, while metribuzine and methyltriazine-amine was always low. Organic matter and soil pH was shown to

Carsten S. Jacobsen; Peter van der Keur; Bo V. Iversen; Per Rosenberg; Heidi C. Barlebo; Søren Torp; Henrik Vosgerau; René K. Juhler; Vibeke Ernstsen; Jim Rasmussen; Ulla Catrine Brinch; Ole Hørbye Jacobsen

2008-01-01

124

American Burying Beetle Research.  

National Technical Information Service (NTIS)

The American burying beetle, (Nicrophorus americanus) is a member of the carrion beetle family Silphidae, an important group of detritivores that recycle decaying materials into the ecosystem. The American burying beetle is the largest carrion-feeding ins...

W. W. Hoback

2008-01-01

125

Digital Horizons  

NSDL National Science Digital Library

Digital Horizons was established in 2007 by a consortium that includes Prairie Public Broadcasting, the State Historical Society of North Dakota, and several other organizations. The goal of their work is to provide and maintain access to "a wide range of historical and significant content related to North Dakota and Minnesota." Visitors can use the search engine here to look for items by general subject heading or collection. All told, there are over fifteen collections included in this archive, including "Korean War Propaganda Leaflets", "Dakota Lithographs and Engravings", and "North Dakota Blue Books". For those looking for a place to start, they can take advantage of the "Popular Searches" list, which includes topical headings such as "floods", "bonanza farms", and "homesteading". This last heading is a great place to check out, as visitors will find evocative (and sometimes quite lonely) photographs of 19th century homesteads.

126

Molecular Investigation of the Short-term Sequestration of Natural Abundance 13C -labelled Cow Dung in the Surface Horizons of a Temperate Grassland Soil  

NASA Astrophysics Data System (ADS)

An adequate understanding of the carbon (C) sequestration potential of grasslands requires that the quantity and residence times of C inputs be measured. Herbivore dung is largely comprised of plant cell wall material, a significant source of stable C in intensively grazed temperate grassland ecosystems that contributes to the soil carbon budget. Our work uses compound-specific isotope analysis to identify the pattern of input of dung-derived compounds from natural abundance 13C/-labelled cow dung into the surface horizons of a temperate grassland soil over one year. C4 dung (? 13C \\-12.6 ‰ ) from maize fed cows was applied to a temperate grassland surface (? 13C \\-29.95 ‰ ) at IGER-North Wyke (Devon, UK), and dung remains and soil cores beneath the treatments collected at ? = 7, 14, 28, 56, 112, 224 and 372 days. Bulk dung carbon present in the 0\\-1 cm and 1\\-5 cm surface horizons of a grassland soil over one year was estimated using ? 13C between C4 dung and C3 dung, after Bol {\\et al.} (2000). The major biochemical components of dung were quantified using proximate forage fibre analyses, after Goering and Van Soest (1970) and identified using `wet' chemical and GC-MS methods. Plant cell wall polysaccharides and lignin were found to account for up to 67 {%} of dung dry matter. Hydrolysed polysaccharides were prepared as alditol acetates for analyses (after Docherty {\\et al.}, 2001), and a novel application of an off-line pyrolysis method applied to measure lignin-derived phenolic compounds (after Poole & van Bergen, 2002). This paper focuses on major events in the incorporation of dung carbon, estimated using natural abundance 13C&-slash;labelling technique. This revealed a major bulk input of dung carbon after a period of significant rainfall with a consequent decline in bulk soil ? 13C values until the end of the experiment (Dungait {\\et al.}, submitted). Findings will be presented revealing contribution of plant cell wall polysaccharides and lignin to these bulk ? 13C values, and their potential for sequestration considered. References: Bol, R., Amelung, W., Friedrich, C. Ostle, N. (2000). Tracing dung-derived carbon in temperate grassland using 13C natural abundance measurements. Soil Biology and Biochemistry, 32, 1337-1343. Goering and Van Soest (1970). Forage fibre analysis (apparatus, reagents, procedures and some applications). In: USDA-ARS Agricultural Handbook, 379. U. S. Government Printing Office, Washington D.C. Docherty, G., Jones, V. and Evershed, R.P. (2001). Practical and theoretical considerations in the gas chromatography/combustion/isotope ratio mass spectrometry ? 13C analysis of small polyfunctional compounds. Rapid Communications in Mass Spectrometry, 15, 730-738. Poole, I. & van Bergen, P. F. (2002). Carbon isotope ratio analysis of organic moieties from fossil mummified wood: establishing optimum conditions for off-line pyrolysis extraction using gas chromatography/mass spectrometry. Rapid Communications in Mass Spectrometry, 16, 1976-1981. Dungait, J. A. J., Bol, R. and Evershed, R.P. (submitted). The Fate of Dung Carbon in Temperate Grassland Soil: 1. Preliminary Findings Based on Bulk Stable Carbon Isotope Determinations. Isotopes in Health and Environmental Studies

Dungait, J.; Bol, R.; Evershed, R. P.

2004-12-01

127

Ionic charge, radius, and potential control root/soil concentration ratios of fifty cationic elements in the organic horizon of a beech (Fagus sylvatica) forest podzol.  

PubMed

The root/organic soil concentration ratio; R/S) of 50 cationic mineral elements was related to their ionic properties, including ionic radius (r), ionic charge (z), and ionic potential (z/r or z2/r). The materials studied were ectomycorrhizal beech (Fagus sylvatica L.) roots and their almost purely organic soil substrate, the O-horizon (mor; raw humus) of a Podzol in South Sweden, developed in a site which has been untouched by forestry or other mechanical disturbance since at least 50 years and located in an area with no local sources of pollution. Elements determined by ICP-AES were aluminium, barium, calcium, iron, potassium, magnesium, manganese, sodium and strontium. Determined by ICP-MS were silver, beryllium, bismuth, cadmium, cerium, cobalt, chromium, caesium, copper, dysprosium, erbium, europium, gallium, gadolinium, hafnium, mercury, holmium, indium, lanthanum, lithium, lutetium, niobium, neodymium, nickel, lead, praseodymium, rubidium, scandium, samarium, tin, terbium, thorium, titanium, thallium, thulium, uranium, vanadium, yttrium, ytterbium, zinc and zirconium. The R/S ratios were most clearly related to the ionic potential of the cationic elements studied, which accounted for approximately 60% of the variability in R/S among elements. The ionic charge of an element was more important than the ionic radius. Elements with high ionic charge had low R/S ratios and vice versa. No clear differences in R/S between essential and non-essential plant nutrients were observed, especially when ions of similar charge were compared. PMID:15262169

Tyler, Germund

2004-08-15

128

Changes in Fungal Community Composition in Response to Elevated Atmospheric CO2 and Nitrogen Fertilization Varies with Soil Horizon  

PubMed Central

Increasing levels of atmospheric carbon dioxide (CO2) and rates of nitrogen (N)-deposition to forest ecosystems are predicted to alter the structure and function of soil fungal communities, but the spatially heterogeneous distribution of soil fungi has hampered investigations aimed at understanding such impacts. We hypothesized that soil physical and chemical properties and fungal community composition would be differentially impacted by elevated atmospheric CO2 (eCO2) and N-fertilization in spatially separated field samples, in the forest floor, 0–2, 2–5, and 5–10?cm depth intervals in a loblolly pine Free-Air Carbon Dioxide Enrichment (FACE) experiment. In all soils, quantitative PCR-based estimates of fungal biomass were highest in the forest floor. Fungal richness, based on pyrosequencing of the fungal ribosomal large subunit gene, increased in response to N-fertilization in 0–2?cm and forest floor intervals. Composition shifted in forest floor, 0–2 and 2–5?cm intervals in response to N-fertilization, but the shift was most distinct in the 0–2?cm interval, in which the largest number of statistically significant changes in soil chemical parameters (i.e., phosphorus, organic matter, calcium, pH) was also observed. In the 0–2?cm interval, increased recovery of sequences from the Thelephoraceae, Tricholomataceae, Hypocreaceae, Clavicipitaceae, and Herpotrichiellaceae families and decreased recovery of sequences from the Amanitaceae correlated with N-fertilization. In this same depth interval, Amanitaceae, Tricholomataceae, and Herpotriciellaceae sequences were recovered less frequently from soils exposed to eCO2 relative to ambient conditions. These results demonstrated that vertical stratification should be taken into consideration in future efforts to elucidate environmental impacts on fungal communities and their feedbacks on ecosystem processes.

Weber, Carolyn F.; Vilgalys, Rytas; Kuske, Cheryl R.

2013-01-01

129

Spatial and temporal distribution of soil organic carbon in nonsorted striped patterned ground of the High Arctic  

Microsoft Academic Search

The role of periglacial processes on soil carbon distribution is examined at a High Arctic site in northwest Greenland. A 16-m trench dug across a series of nonsorted stripes at Thule Air Base revealed sand-rich wedges underlying striped, vegetated troughs, and organic-rich soil horizons buried at depth. The site has sparse prostrate vegetation and is estimated to contain 9.4 kg\\/m2

Jennifer L. Horwath; Ronald S. Sletten; Birgit Hagedorn; Bernard Hallet

2008-01-01

130

Variability of organic material in surface horizons of the hyper-arid Mars-like soils of the Atacama Desert  

NASA Astrophysics Data System (ADS)

The objective of this work was to investigate the variability of surface organic carbon within the hyper-arid Yungay region of the Atacama Desert. The fraction of Labile Organic Carbon (LOC) in these samples varied from 2 to 73 ?g per gram of soil with a bi-modal distribution with average content of 17 ± 9 ?g LOC and 69 ± 3 ?g LOC for "low" and "high" samples, respectively. Interestingly, there was no relation between organic levels and geomorphologic shapes. While organics are deposited and distributed in these soils via eolic processes, it is suggested that fog is the dynamic mechanism that is responsible for the variability and peaks in organic carbon throughout the area, where a "high" LOC content sample could be indicative of a biological process. It was determined that there was no significant difference between topological feature or geographical position within the hyper-arid samples and LOC. This very curious result has implications for the investigation of run-off gullies on the planet Mars as our work suggests a need for careful consideration of the expectation of increases in concentrations of organic materials associated with following aqueous altered topology.

Fletcher, Lauren E.; Valdivia-Silva, Julio E.; Perez-Montaño, Saul; Condori-Apaza, Renee M.; Conley, Catharine A.; McKay, Christopher P.

2012-01-01

131

Remote technologies for buried waste retrieval  

SciTech Connect

The DOE is evaluating what should be done with this buried waste. Although the radioactive waste is not particularly mobile unless airborne, some of it was buried with volatile organics and/or other substances that tend to spread easily to surrounding soil or water tables. Volatile organics are hazardous materials (such as trichloroethylene) and require clean-up at certain levels in drinking water. There is concern that the buried volatile organics will spread into the water table and contaminate drinking water. Because of this, the DOE is considering options for handling this buried waste and reducing the risks of spreading or exposure. There are two primary options: containment and stabilization, or retrieval. Containment and stabilization systems would include systems that would leave the waste where it is, but contain and stabilize it so that the radioactive and hazardous materials would not spread to the surrounding soil, water, or air. For example, an in situ vitrification system could be used to melt the waste into a composite glass-like material that would not leach into the surrounding soil, water, or air. Retrieval systems are those that would remove the waste from its burial location for treatment and/or repackaging for long term storage. The objective of this project was to develop and demonstrate remote technologies that would minimize dust generation and the spread of airborne contaminants during buried waste retrieval. Remote technologies are essential for the retrieval of buried waste because they remove workers from the hazardous environment and provide greater automation, reducing the chances of human error. Minimizing dust generation is also essential to increased safety for the workers and the environment during buried waste retrieval. The main contaminants within the waste are micron-sized particles of plutonium and americium oxides, chlorides, and hydroxides, which are easily suspended in air and spread if disturbed.

Smith, A.M.; Rice, P.

1995-10-01

132

Chemical detection of buried landmines  

SciTech Connect

Of all the buried landmine identification technologies currently available, sensing the chemical signature from the explosive components found in landmines is the only technique that can classify non-explosive objects from the real threat. In the last two decades, advances in chemical detection methods has brought chemical sensing technology to the foreground as an emerging technological solution. In addition, advances have been made in the understanding of the fundamental transport processes that allow the chemical signature to migrate from the buried source to the ground surface. A systematic evaluation of the transport of the chemical signature from inside the mine into the soil environment, and through the soil to the ground surface is being explored to determine the constraints on the use of chemical sensing technology. This effort reports on the results of simulation modeling using a one-dimensional screening model to evaluate the impacts on the transport of the chemical signature by variation of some of the principal soil transport parameters.

Phelan, J.M.; Webb, S.W.

1998-03-01

133

A Numerical Model for Cathodic Protection of Buried Pipes  

Microsoft Academic Search

A mathematical modeling of large, cathodically protected, buried pipe networks was undertaken. The resulting model, OKAPPI, an abbreviation for the Dutch Ondergrondse Kathodische Protectie Pijpleidingen'', coupled the boundary element method (BEM) and the finite element method (FEM) for the cathodic protection of buried pipes. The approach was based on the assumption that the soil was homogeneous, and the local earth

F. Brichau; J. Deconinck

1994-01-01

134

Comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometry for the forensic study of cadaveric volatile organic compounds released in soil by buried decaying pig carcasses.  

PubMed

This article reports on the use of comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometry (GC×GC-TOFMS) for forensic geotaphonomy application. Gravesoil samples were collected at various depths and analyzed for their volatile organic compound (VOC) profile. A data processing procedure was developed to highlight potential candidate marker molecules related to the decomposition process that could be isolated from the soil matrix. Some 20 specific compounds were specifically found in the soil sample taken below the carcass and 34 other compounds were found at all depths of the gravesoil samples. The group of the 20 compounds consisted of ketones, nitriles, sulfurs, heterocyclic compounds, and benzene derivatives like aldehydes, alcohols, ketones, ethers and nitriles. The group of the 34 compounds consisted of methyl-branched alkane isomers including methyl-, dimethyl-, trimethyl-, tetramethyl-, and heptamethyl-isomers ranging from C(12) to C(16). A trend in the relative presence of these alkanes over the various layers of soils was observed, with an increase in the amount of the specific alkanes when coming from the carcass to the surface. Based on the specific presence of these methyl-branched alkanes in gravesoils, we created a processing method that applies a specific script to search raw data for characteristic mass spectral features related to recognizable mass fragmentation pattern. Such screening of soil samples for cadaveric decomposition signature was successfully applied on two gravesoil sites and clearly differentiates soils at proximity of buried decaying pig carcasses from control soils. PMID:22520639

Brasseur, Catherine; Dekeirsschieter, Jessica; Schotsmans, Eline M J; de Koning, Sjaak; Wilson, Andrew S; Haubruge, Eric; Focant, Jean-Francois

2012-04-03

135

Soils and cultural layers in Velikii Novgorod  

NASA Astrophysics Data System (ADS)

Urban pedosediments (cultural layers) dating back to the 10th-11th centuries AD and soddypodzolic soils buried under them were studied in two archaeological excavations in Velikii Novgorod. Stages of their development were described. It was found that the buried soddy-podzolic soils at the latest stages of their development were cultivated or were formed under meadow vegetation. Weakly developed garden soils were described in the thickness of urban pedosediments. The lowermost organic cultural layers in Velikii Novgorod were waterlogged and represented peatlike mass with well-preserved wood remains. The oxidation of organic matter, gleyzation, and vivianite formation were described in them. The upper mineral layers were enriched in brick debris and building lime. The processes of organic matter mineralization, alkalization, calcification, zoogenic turbation, and biogenic structuring were clearly manifested in this part. Soil solutions infiltrated from the cultural layers caused some alkalization of the buried soddy-podzolic soil. Diagenetic carbonates and vivianite appeared in some loci within the eluvial and the upper part of the illuvial horizon of this soil. The entire cultural layer was subjected to contamination with heavy metals.

Dolgikh, A. V.; Aleksandrovskii, A. L.

2010-05-01

136

Temporal change in molecular weight distribution of hot-water extractable organic nitrogen from cattle manure compost buried in soil using high-performance size exclusion chromatography with chemiluminescent nitrogen detection  

NASA Astrophysics Data System (ADS)

The application of compost can improve the fertility of the agricultural soils. The compost organic nitrogen is absorbed by plants after degradation and mineralization. To investigate the degradation process of compost organic nitrogen in soil, we conducted soil burial test of compost and observed the molecular weight distribution of hot-water extractable organic nitrogen from the compost. The cattle manure compost (1g) was mixed with soil (25g), put into glass fiber-filter paper bag and buried in 15 cm under surface of the ground for 6 months. The soils used were Andosol, Gray Lowland soil, and Yellow soil without organic matter application for 25 years in Tsukuba, Japan. Organic matter was extracted from the buried sample with 80° C of water for 16 hours. The molecular weight distribution of the hot-water extractable organic matter (HWEOM) was measured by high-performance size exclusion chromatography and chemiluminescent nitrogen detection (HPSEC/CLND). In this system, N-containing compound eluted from a SEC column was introduced into a furnace at 1050° C, and N in the compound was oxidized to nitric oxide and then detected using a chemiluminescent reaction with ozone. The N chromatogram showed that N in the HWEOM from the soil with compost had various molecular weights ranging from 0.1 to 100 kDa. A void peak (>100 kDa), a broad peak around 30 kDa, and several sharp peaks less than 30 kDa were observed in the chromatogram. The broad peak (~ 30kDa) was likely to be derived from the compost, because it was not observed in the chromatogram of HWEOM from soil alone. The N intensities of all peaks decreased with burial time, especially, the broad peak (~30 kDa) intensity rapidly decreased by 10 - 50 % in only first 2 months. The decreasing rates of the broad peak were higher than that of the sharp peaks, indicating that the organic nitrogen with a larger molecular weight decomposed faster. The broad peak (~ 30 kDa) had visible (420nm) absorption and less fulvic acid like florescence (Ex340nm, Em440 nm). The several sharp peaks had small visible absorption and intense florescence. Further studies are needed to assign the chemical forms for each peak.

Moriizumi, M.; Mutsunaga, T.

2012-04-01

137

Improved thermal analysis of buried landmines  

Microsoft Academic Search

In this paper, we address the problem of the detection and identification of surface-laid and shallowly buried landmines from measured infrared images. A three-dimensional thermal model has been developed to study the effect of the presence of landmines in the thermal signature of the bare soil. Based on this model, a target identification procedure is proposed aiming at detecting and

Paula López Martínez; Luc van Kempen; Hichem Sahli; Diego Cabello Ferrer

2004-01-01

138

Nonlinear vibrations of buried landmines.  

PubMed

The seismo-acoustic method is one of the most promising emerging techniques for the detection of landmines. Numerous field tests have demonstrated that buried landmines manifest themselves at the surface through linear and nonlinear responses to acoustic/seismic excitation. The present paper describes modeling of the nonlinear response in the framework of the mass-spring model of the soil-mine system. The perturbation method used in the model allows for the derivation of an analytical solution describing both quadratic and cubic acoustic interactions at the soil-mine interface. This solution has been compared with actual field measurements to obtain nonlinear parameters of the buried mines. These parameters have been analyzed with respect to mine types and burial depths. It was found that the cubic nonlinearity could be a significant contributor to the nonlinear response. This effect has led to the development of a new intermodulation detection algorithm based on dual-frequency excitation. Both quadratic and intermodulation nonlinear algorithms were evaluated at the U.S. Army outdoor testing facilities. The algorithms appear to complement each other in improving the overall detection performance. PMID:15759689

Donskoy, Dimitri; Reznik, Alexander; Zagrai, Andrei; Ekimov, Alexander

2005-02-01

139

The 2011 Horizon Report  

ERIC Educational Resources Information Center

The internationally recognized series of "Horizon Reports" is part of the New Media Consortium's Horizon Project, a comprehensive research venture established in 2002 that identifies and describes emerging technologies likely to have a large impact over the coming five years on a variety of sectors around the globe. This volume, the "2011 Horizon

Johnson, L.; Smith, R.; Willis, H.; Levine, A.; Haywood, K.

2011-01-01

140

Security of Shallow-buried Oil-pipeline in the freeze-thaw processes of frost-soil bed in cold-region  

Microsoft Academic Search

According to the particularity of cold-region for its geographical and climatic environments where the oil-pipeline is laid, the author adopts suitably physical parameters and mathematical-physical models involved in the oil-pipeline system, to simulate the boundary conditions of ground surfaces and the region where oil-pipeline is located, constructing finite element (FE) analysis models of the coupled freezing process of shallow buried

Nansheng Li; Yu Wang

2011-01-01

141

EVALUATION OF ROOT GROWTH LIMITING FACTORS IN SPODIC HORIZONS OF SPODOSOLS  

Microsoft Academic Search

Spodic horizon in Spodosols often restricts growth of plant roots. Generally the Spodic horizon is acidic with high levels of aluminum (Al). In this study soil solution Al was characterized in the Spodic horizon and the respective surface horizon of three Spodosols in the major citrus production region in Florida. The soil pH ranged from 4.92 to 5.14, and 4.82

A. K. Alva; B Huang; S Paramasivam; K. S. Sajwan

2002-01-01

142

Pedogenesis of Vesicular Horizons, Cima Volcanic Field, Mojave Desert, California  

Microsoft Academic Search

the underlying vesicular horizon coevolves with pavement formation. Results presented here support this model and provide a mechanism understood. Chemical, physical, and micromorphologi- whereby eolian material is transported from the ground surface to cal data on vesicular soil peds are presented here that ped interiors, thereby increasing the thickness of the vesicular horizon help identify the processes of dust translocation

K. Anderson; S. Wells; R. Graham

2002-01-01

143

Analysis of IR signatures of surface and buried antitank landmines  

Microsoft Academic Search

The thermal signatures of surface and buried land mines vary widely with time of day, weather, soil type, soil moisture content, and mine burial depth. There have been recent advances in modeling these effects, but until these models are fully developed and validated we will continue to rely on measured data. This paper witll present signatures in the medium-and long-wavelength

Meghan A. McGovern; Hilda I. Aponte

2001-01-01

144

Spherically symmetric quantum horizons  

SciTech Connect

Isolated horizon conditions specialized to spherical symmetry can be imposed directly at the quantum level. This answers several questions concerning horizon degrees of freedom, which are seen to be related to orientation, and its fluctuations at the kinematical as well as dynamical level. In particular, in the absence of scalar or fermionic matter the horizon area is an approximate quantum observable. Including different kinds of matter fields allows to probe several aspects of the Hamiltonian constraint of quantum geometry that are important in inhomogeneous situations.

Bojowald, Martin; Swiderski, Rafal [Max-Planck-Institut fuer Gravitationsphysik, Albert-Einstein-Institut, Am Muehlenberg 1, D-14476 Potsdam (Germany); Max-Planck-Institut fuer Gravitationsphysik, Albert-Einstein-Institut, Am Muehlenberg 1, D-14476 Potsdam (Germany)

2005-04-15

145

30 CFR 823.14 - Soil replacement.  

Code of Federal Regulations, 2010 CFR

...minimum, physical and chemical characteristics of reconstructed soils and soil descriptions containing soil-horizon depths, soil densities, soil pH, and other specifications such that reconstructed soils will have the capability of achieving...

2010-07-01

146

30 CFR 823.14 - Soil replacement.  

Code of Federal Regulations, 2010 CFR

...minimum, physical and chemical characteristics of reconstructed soils and soil descriptions containing soil-horizon depths, soil densities, soil pH, and other specifications such that reconstructed soils will have the capability of achieving...

2009-07-01

147

Soil stratigraphy and plant soil interactions on a Late Glacial Holocene fluvial terrace sequence, Sierra Nevada National Park, northern Venezuelan Andes  

NASA Astrophysics Data System (ADS)

Analysis of a flight of alluvial terraces in the Sierra Nevada National Park near Pico Mucuñuque in the Eastern Mérida Andes has yielded information on geomorphic, pedogenic, and vegetational changes from Late Glacial time to the present. The terraces formed in large part due to stream incision/migration triggered by neotectonic uplift (>7000 yr BP) of a Late Glacial/Early Holocene glaciolacustrine lithosequence and, with the exception of the oldest/highest terrace, exhibit near-uniform lithology/parent materials. Soils developed in the terrace materials range from thin, weakly developed profiles (O/C/Cu horizons) to Entisols with O/Ah/Cox/Cu horizons and similar buried counterparts representing former short periods of floodplain stability or slow aggradation. The buried soils provide organic-rich material that yields radiocarbon ages, which provide time constraints on individual pedons and the geomorphic development of the site. Iron and aluminum extracts of soil matrix material provide information on the formation and accumulation of goethite and hematite, the relative accumulation of ferrihydrite (gain/loss), and the downward translocation of organically complexed Al as a function of soil development and age. SEM analysis of heavy mineral grains indicates varying material sources and degrees of weathering in the soil chronosequence. A qualitative study of plant functional types across the terrace sequence shows that older surfaces support greater plant diversity. The study also suggests ways in which the plant communities influence soil development at the site through varying organic matter inputs and varying soil moisture use by specific species (e.g., ferns on the oldest terrace), which may explain the absence of B horizons in the Late Pleistocene/Early Holocene soils.

Mahaney, William C.; Dirszowsky, Randy W.; Milner, Michael W.; Harmsen, Rudolf; Finkelstein, Sarah A.; Kalm, Volli; Bezada, Maximilano; Hancock, R. G. V.

2007-01-01

148

Laboratory Load Tests on Buried Flexible Pipe. Progress Report No. 5. Fiberglass Reinforced Plastic (FRP), Polyethylene (PE), and Polyvinyl Chloride (PVC) Pipe.  

National Technical Information Service (NTIS)

Laboratory tests were conducted to investigate the behavior of buried flexible pipes. Kinds of pipe tested were fiberglass reinforced plastic (FRP), polyvinyl chloride (PVC), and polyethylene (PE). The pipes were buried in a large, steel, soil container i...

A. K. Howard

1973-01-01

149

Sensor feature fusion for detecting buried objects  

SciTech Connect

Given multiple registered images of the earth`s surface from dual-band sensors, our system fuses information from the sensors to reduce the effects of clutter and improve the ability to detect buried or surface target sites. The sensor suite currently includes two sensors (5 micron and 10 micron wavelengths) and one ground penetrating radar (GPR) of the wide-band pulsed synthetic aperture type. We use a supervised teaming pattern recognition approach to detect metal and plastic land mines buried in soil. The overall process consists of four main parts: Preprocessing, feature extraction, feature selection, and classification. These parts are used in a two step process to classify a subimage. Thee first step, referred to as feature selection, determines the features of sub-images which result in the greatest separability among the classes. The second step, image labeling, uses the selected features and the decisions from a pattern classifier to label the regions in the image which are likely to correspond to buried mines. We extract features from the images, and use feature selection algorithms to select only the most important features according to their contribution to correct detections. This allows us to save computational complexity and determine which of the sensors add value to the detection system. The most important features from the various sensors are fused using supervised teaming pattern classifiers (including neural networks). We present results of experiments to detect buried land mines from real data, and evaluate the usefulness of fusing feature information from multiple sensor types, including dual-band infrared and ground penetrating radar. The novelty of the work lies mostly in the combination of the algorithms and their application to the very important and currently unsolved operational problem of detecting buried land mines from an airborne standoff platform.

Clark, G.A.; Sengupta, S.K.; Sherwood, R.J.; Hernandez, J.E.; Buhl, M.R.; Schaich, P.C.; Kane, R.J.; Barth, M.J.; DelGrande, N.K.

1993-04-01

150

Liquefaction hazards and their effects on buried pipelines. Technical report  

SciTech Connect

This research involves the evaluation of liquefaction-induced ground movements and their effects on buried pipelines. The work is divided into three components: review of liquefaction phenomena and associated ground displacements; characterization of liquefaction-induced lateral spreading through observations and measurements of lateral spread deformations during past earthquakes; parametric study to evaluate buried pipeline response as a function of soil properties and geometric characteristics of lateral spreads. Case studies of four earthquakes were reviewed in which occurrences of lateral spreading have been reported. The results of the case studies indicate a close relationship between geologic and morphologic conditions and the occurrence and pattern of lateral spreading. The parametric study demonstrates the strong influence of geometric characteristics of the soil displacements on buried pipeline response. The delineation of zones of potentially large ground movement and the estimation of displacement patterns can be useful in the design of future pipeline systems, and the modification of existing ones, to limit earthquake damage.

O'Rourke, T.D.; Lane, P.A.

1989-02-01

151

High water-loss rates and rapid dehydration in the burying beetle, Nicrophorus marginatus  

Microsoft Academic Search

During the summer months, there is a high mortality of burying beetle (Coleoptera: Silphidae) species in pitfall traps containing dry soil. The present study investigated the possibility that the burying beetle Nicrophorus marginatus is highly susceptible to death from desiccation. In the laboratory, adult beetles lose 1-5% body mass per hour in low humidity conditions (25-30% relative humid- ity), depending

JON C. B EDICK; W. W Y ATT; C. A LBRECHT

152

Buried object characterization via ground-penetrating radar and Huynen polarimetric parameters  

Microsoft Academic Search

A known target buried underground and illuminated from the air on its top flat surface by a ground-penetrating radar (GPR) is used to verify the results of a polarization approach that uses the Huynen parameters. The target is a dielectric cylinder of diameter d and height h that simulates a land mine buried in soil, flat top surface looking up.

Firooz A. Sadjadi; Cornell S. L. Chun; Anders J. Sullivan; Guillermo C. Gaunaurd

2005-01-01

153

Buried, viable seeds in two California bunchgrass sites and their bearing on the definition of a flora  

Microsoft Academic Search

A complete description of a plant community must include the buried viable seeds in the soil. The plants occurring in this form are a part of the flora, which helps to determine the community, even though they are not readily evident. The importance of defining an ecosystem's flora is reviewed. When the soil's buried viable seed population is used to

Jack Major; William T. Pyott

1966-01-01

154

Filial cannibalism in burying beetles  

Microsoft Academic Search

Infanticide is a common phenomenon in many animal groups, but filial cannibalism, the deliberate killing and consumption by parents of their own young, is extremely unusual. The burying beetle Nicrophorus vespilloides Herbst has a limited food supply, in the form of a buried corpse, on which to raise its young. On corpses weighing 10–15 g, clutch size in the lab

J. Bartlett

1987-01-01

155

Mt. Blanco revisited: Soil-geomorphic implications for the ages of the upper Cenozoic Blanco and Blackwater Draw Formations  

NASA Astrophysics Data System (ADS)

Mt. Blanco, on the eastern edge of the Southern High Plains of Texas, contains stratigraphic features significant in interpreting the late Cenozoic history of the region and the vertebrate paleontology of the Great Plains; however, the stratigraphic relations are confused in the literature or are unreported. Mt. Blanco is the type locality for the Blanco Formation and the Blanco Local Fauna, which occurs throughout North America and is the type fauna for the Blancan Land Mammal Age in North America. Here also occur exposures of the Blackwater Draw Formation, an extensive (˜120000 km2) eolian sheet that is the surficial cover of the region and contains the 1.4 Ma Guaje Ash and several buried soils. A reexamination of the section shows that (1) the Blackwater Draw Formation, an eolian deposit, contains three well-expressed buried soils (5 YR hues, argillic horizons ?1 m thick, Stages III and IV calcic horizons) and the similar regional surface soil (Paleustalf); (2) the Guaje Ash is within the lower Blackwater Draw Formation but is separated from the Blanco Formation, a lacustrine unit, by about 1 m of sediment, including the lowest buried soil; and (3) the lowest buried soil shows a Stage IV calcrete formed at the top of the Blanco Formation and the base of the Black-water Draw Formation and probably took about 200 ka to form. These new data suggest that deposition of the type Blanco sediments may have ended by about 1.6 Ma or earlier. Since that time, the Blackwater Draw Formation has accumulated episodically; periods of nondeposition are characterized by landscape stability and pedogenesis.

Holliday, Vance T.

1988-06-01

156

Mt. Blanco revisited: soil-geomorphic implications for the ages of the upper Cenozoic Blanco and Blackwater Draw Formations  

SciTech Connect

Mt. Blanco, on the eastern edge of the Southern High Plains of Texas, contains stratigraphic features significant in interpreting the late Cenozoic history of the region and the vertebrate paleontology of the Great Plains; however, the stratigraphic relations are confused in the literature or are unreported. Mt. Blanco is the type locality for the Blanco Formation and the Blanco Local Fauna, which occurs throughout North America and is the type fauna for the Blancan Land Mammal Age in North America. Here also occur exposures of the Blackwater Draw Formation, an extensive (120,000 km/sup 2/) eolian sheet that is the surficial cover of the region and contains the 1.4 Ma Guaje Ash and several buried soils. A reexamination of the section shows that (1) the Blackwater Draw Formation, an eolian deposit, contains three well-expressed buried soils (5 YR hues, argillic horizons greater than or equal to 1 m thick, Stages III and IV calcic horizons) and the similar regional surface soil (Paleustalf); (2) the Guaje Ash is within the lower Blackwater Draw Formation but is separated from the Blanco Formation, a lacustrine unit, by about 1 m of sediment, including the lowest buried soil; and (3) the lowest buried soil shows a Stage IV calcrete formed at the top of the Blanco Formation and the base of the Blackwater Draw Formation and probably took about 200 ka to form. These new data suggested that deposition of the type Blanco sediments may have ended by about 1.6 Ma or earlier. Since that time, the Blackwater Draw Formation has accumulated episodically; periods of nondeposition are characterized by landscape stability and pedogenesis.

Holliday, V.T.

1988-06-01

157

Soil Composition  

NSDL National Science Digital Library

Soil is essential for life on Earth. It is needed for food, air, clothing and so much more. Discussion topics include the terms 'soil', 'dirt', and 'sediment', factors affecting the formation of soils, soil horizons, and the twelve orders of soils. In a hands-on activity, students will collect soil samples from three different locations, use online resources to determine texture and particle makeup, and record their observations.

Fox, Chris; Pratte, John

158

Assessment of the living and total biomass of microbial communities in the background chestnut soil and in the paleosols under burial mounds  

NASA Astrophysics Data System (ADS)

The contents of phospholipids and carbon of the total microbial biomass were determined in the modern chestnut soil and in the paleosols buried under mounds of the Bronze and Early Iron Ages (5000-1800 years ago) in the dry steppe of the Lower Volga River basin. Judging from data on the ratio between the contents of phospholipids and organic carbon in the microbial cells, the carbon content of the living microbial biomass was calculated and compared with the total microbial biomass and total organic carbon in the studied soils. In the background chestnut soil, the content of phospholipids in the A1, B1, and B2 horizons amounted to 452, 205, and 189 nmol/g, respectively; in the paleosols, it was 28-130% of the present-day level. The maximum content was measured in the paleosols buried 5000 and 2000 years ago, in the periods with an increased humidity of the climate. In the background chestnut soil, the total microbial biomass was estimated at 5680 (the A1 horizon), 3380 (B1), and 4250 (B2) ?g C/g; in the paleosols, it was by 2.5-7.0 times lower. In the upper horizons of the background soil, the portion of the living microbial biomass in the total biomass was much less than that in the paleosols under the burial mounds; it varied within 8.5-15.3% and 15-81%, respectively. The portion of living microbial biomass in the total organic carbon content of the background chestnut soil was about 4-8%. In the paleosols buried in the Early Iron Age (2000 and 1800 years ago), this value did not exceed 3-8%; in the paleosols of the Bronze Age (5000-4000 years ago), it reached 40% of the total organic carbon.

Khomutova, T. E.; Kashirskaya, N. N.; Demkin, V. A.

2011-12-01

159

HIGHER HORIZONS PROGRAM.  

ERIC Educational Resources Information Center

|THE HIGHER HORIZONS PROGRAM GREW OUT OF THE DEMONSTRATION GUIDANCE PROJECTS, A 6-YEAR PROGRAM TO HELP PREVENT DROPOUTS. EXTENSION OF THESE SERVICES TO OTHER JUNIOR HIGH AND ELEMENTARY SCHOOLS OF VARIED ECONOMIC STANDING AND TO ALL STUDENTS WITHIN THESE SCHOOLS WAS PLANNED. THE PROGRAM IN 1960-61 INVOLVED 13 JUNIOR HIGH SCHOOLS AND 52 ELEMENTARY…

New York City Board of Education, Brooklyn, NY.

160

How to detect buried structures through electrical measurements  

Microsoft Academic Search

The experiment reported here, performed by advanced undergraduates as a final laboratory work, was intended as an example of the application of the electricity theory to solve problems related to environmental physics. In particular, the aim of the work was to show how we can get the electrical image of the soil and detect the presence of buried structures from

Ana Osella; Gabriel Chao; Federico Sánchez

2001-01-01

161

Spacetimes containing slowly evolving horizons  

SciTech Connect

Slowly evolving horizons are trapping horizons that are ''almost'' isolated horizons. This paper reviews their definition and discusses several spacetimes containing such structures. These include certain Vaidya and Tolman-Bondi solutions as well as (perturbatively) tidally distorted black holes. Taking into account the mass scales and orders of magnitude that arise in these calculations, we conjecture that slowly evolving horizons are the norm rather than the exception in astrophysical processes that involve stellar-scale black holes.

Kavanagh, William; Booth, Ivan [Department of Physics and Physical Oceanography, Memorial University of Newfoundland St. John's, Newfoundland and Labrador, A1B 3X7 (Canada); Department of Mathematics and Statistics, Memorial University of Newfoundland St. John's, Newfoundland and Labrador, A1C 5S7 (Canada)

2006-08-15

162

Insect arrival pattern and succession on buried carrion in Michigan.  

PubMed

This study examined pig carcasses buried at two different depths, 30 and 60 cm, to determine if insects were able to colonize buried carcasses, when they arrive at each depth, and what fauna were present over seven sampling dates to establish an insect succession database on buried carrion in East Lansing, MI. Thirty-eight pigs were buried, 18 at 30 cm and 20 at 60 cm. Four control carcasses were placed on the soil surface. Three replicates at each depth were exhumed after 3, 7, 14, 21, 30, and 60 d, respectively. One pig also was exhumed from 60 cm after 90 d and another after 120 d. Sarcophaga bullata (Parker) (Diptera: Sarcophagidae) and Hydrotaea sp. (Diptera: Muscidae) were found colonizing buried carrion 5 d after burial at 30 cm. Insect succession at 30 cm proceeded with flesh and muscid flies being the first to colonize, followed by blow flies. Insects were able to colonize carcasses at 60 cm and Hydrotaea sp. and Megaselia scalaris (Loew) (Diptera: Phoridae) were collected 7 d after burial. Insect succession at 60 cm did not proceed similarly, instead muscid and coffin flies were the only larvae collected. Overall these results reveal postburial interval estimates for forensic investigations in mid-Michigan during the summer, depending on climatic and soil conditions. PMID:23540133

Pastula, E C; Merritt, R W

2013-03-01

163

Method and apparatus for constructing buried pipeline systems  

SciTech Connect

A method and apparatus for mitigating or eliminating the frost heave of refrigerated pipelines buried in frost-susceptible soil are provided. A blanket of heat absorbent material is placed over the pipeline on the surface of the soil to increase the flow of heat into the region surrounding the pipeline. This technique may be used in combination with other frost heave mitigation techniques, such as insulating the pipeline and supporting the pipeline with a heave resistant bedding material.

Heuer, C.E.; Hsu, H.; Jahns, H.O.

1982-11-09

164

Hard-pan soils - Management  

Technology Transfer Automated Retrieval System (TEKTRAN)

Hard pans, hard layers, or compacted horizons, either surface or subsurface, are universal problems that limit crop production. Hard layers can be caused by traffic or soil genetic properties that result in horizons with high density or cemented soil particles; these horizons have elevated penetrati...

165

Field-Measured Infiltration Properties of Mojave Desert Soils  

NASA Astrophysics Data System (ADS)

Characteristics typical of alluvial desert soils, such as depositional stratification, desert pavement, biotic crusts, and vesicular horizons strongly influence soil moisture and its variability. Knowledge of infiltration capacity, water retention, and unsaturated hydraulic conductivity is central to the assessment of water availability to plants and animals after infiltration events. These hydraulic parameters are directly related to the degree of soil development. The frequency and magnitude of storm events in conjunction with degree of soil development also affect runoff and erosion. Our purpose is to examine field soil-water behavior and determine unsaturated hydraulic properties needed for large-scale modeling of soil moisture. The results of this study will be used in conjunction with surficial geologic mapping of the Mojave Desert in evaluations of ecological habitat quality. We conducted infiltration/redistribution experiments on three different-aged deposits in the Mojave National Preserve: (1) recently deposited wash sediments, (2) a soil of early Holocene age, and (3) a highly developed soil of late Pleistocene age. In each experiment we ponded water in a 1-m-diameter infiltration ring for 2.3 hr. For several weeks we monitored water content and matric pressure to depths of 1.5 m, and distances of 6 m from the infiltration ring. Measuring techniques included surface electrical resistance tomography, dielectric-constant probes, heat-dissipation probes, and tensiometers. Analysis of the subsurface measurements using an instantaneous-profile technique gives the retention and K properties that will be used in predictive modeling. In each experiment the infiltration rate was nearly constant in time, with infiltration capacity 4 times greater in the youngest than in the oldest soil. Average infiltration flux densities within the ring during the period of ponding were 0.80 m/hr in the active wash, 0.45 m/hr in the Holocene soil, and 0.21 m/hr in the Pleistocene soil. All three deposits have significant gravel (30-70% within the uppermost 1.5 m) with the percentage of silt and clay increasing with deposit age. The low infiltration capacity in the oldest soil is consistent with the presence of the more highly developed vesicular horizon and accumulation of illuvial silt. Depositional stratification in the active wash did not impede downward flow to the same degree as in the early Holocene-age soil, which has some soil horizon development and sparse biotic crust. Infiltrated water spread laterally to at least 1 m beyond the ring perimeter at all sites; the presence of a buried clay-rich horizon in the active wash enhanced spreading at depth to 2 m.

Perkins, K. S.; Nimmo, J. R.; Winfield, K. A.; Schmidt, K. M.; Miller, D. M.; Stock, J. D.; Singha, K.

2005-12-01

166

Landscape evolution and soil hydrological change: new insights from sandy soils in the Campine area, Northern Belgium  

NASA Astrophysics Data System (ADS)

Hydrological properties of soils and sediments as they can be measured today may evolve according to their environmental context during landscape evolution. Linking soil profile development with hydrological changes of particular soil horizons over time scales of several hundreds to thousands of years is a typical example of emerging hydropedological research and is the subject of the current study. For this purpose, a dry podzol profile buried under younger drift sands was investigated using advanced hydrological (Beerten et al., this volume (a)) and geomorphological techniques (Beerten et al., this volume (b)). The principal results suggest that during the last 10 000 years, geomorphological and pedological processes have induced changes in saturated hydraulic conductivity values (Ksat) across the podzol profile resulting in present-day differences of up to four orders of magnitude. The highest values (Ksat ~ 10-3 m/s) are found in ~ 250 year old uncompacted drift sand deposits, while low values are typical for the illuviation horizon (Bh) of podzol soils that developed in Weichselian cover sands (Ksat ~ 10-7 m/s). Detailed investigations show that landscape stabilisation and podzolisation in such sandy substrates under pine and/or heather may lower Ksat-values by an order of magnitude in less than 100 years while higher order changes may take several 1 000 years. It is concluded that soil hydrological properties display large spatial variability even within the same soil profile; this variation was shown to have a strong correlation with the development stage and thus age of the soil horizon. The established relationships may help explain past hydrological changes and improve predictions of future hydrological changes of soils in the Campine area.

Beerten, K.; Mallants, D.

2012-04-01

167

Quadratic Lagrangians and horizons  

SciTech Connect

It has been known for some time that the standard isotropic cosmological model with an {ital R}{sup 2} Lagrangian has horizon-breaking solutions in the {ital t}{r arrow}0 singularity limit. We search for horizonless power-law solutions in the vacuum Bianchi type-I and orthogonal type-V cosmological models. We find that type V with an {ital R}{sup 2} Lagrangian does contain such solutions. At first glance this would suggest that quadratic theories might provide an alternative resolution to the horizon problem. However, for both the horizonless isotropic and type-V solutions we show that the eigenvalues of the linear vector field near the stationary points in phase space have opposite signs, demonstrating that such solutions are not Lyapunov stable. The addition of free quantum fields may stabilize the solutions.

Rothman, T.; Anninos, P. (Department of Physics and Center for Relativity, The University of Texas at Austin, Austin, Texas (USA))

1991-11-15

168

Cosmological apparent and trapping horizons  

NASA Astrophysics Data System (ADS)

The dynamics of particle, event, and apparent horizons in Friedmann-Lemaitre-Robertson-Walker space are discussed. The apparent horizon is trapping when the Ricci curvature is positive. This simple criterion coincides with the condition for the Kodama-Hayward apparent horizon temperature to be positive and also discriminates between the timelike and spacelike character of the apparent horizon. We discuss also the entropy of apparent cosmological horizons in extended theories of gravity and we use the generalized 2nd law to discard an exact solution of Brans-Dicke gravity as unphysical.

Faraoni, Valerio

2011-07-01

169

Numerical Modeling for Impact-resistant Pipes Buried at Shallow Depth  

NASA Astrophysics Data System (ADS)

The plastic pipes buried at shallow depth are popular for underground telecommunication lines. To assess their impact-worthiness under loads from heavy traffics, the study establishes a numerical model to correlate with field data. Field impact tests were carried out where a 50-kg mass free-falling at 2.2 m height was dropped onto the soil backfill directly above a buried pipe. A contact-impact model incorporating finite elements of disjoined material regions is developed to simulate the phenomena of mass-soil-pipe interaction and soil dent. Plastic soil deformations are accounted for. Also implemented is a new erosion scheme for dealing with numerical instability caused by crumpled elements during heavy impact. Reasonable agreements can be observed between the analyzed and measured soil dent. This model is versatile in making design evaluations for buried pipes to withstand impact loads. It has potential applications to cemented soil fills and blast loads.

Wang, Ching-Jong; Hsu, Jung-Fu

2010-05-01

170

Lay, bury method proves effective  

SciTech Connect

The best way to lay and bury a pipeline offshore is to perform both operations simultaneously. Historically these two operations have been separate but recently a simultaneous lay and bury technique has been developed that is technically feasible and cost effective. The technique employs a patented Sea Plow that cuts a trench in the ocean floor into which the pipeline is laid. The operation and performance of the Sea Plow are described.

Fulton, R.N.

1984-08-01

171

Prediction of the TNT signature from buried UXO/landmines  

SciTech Connect

The detection and removal of buried unexploded ordnance (UXO) and landmines is one of the most important problems facing the world today. Numerous detection strategies are being developed, including infrared, electrical conductivity, ground-penetrating radar, and chemical sensors. Chemical sensors rely on the detection of TNT molecules, which are transported from buried UXO/landmines by advection and diffusion in the soil. As part of this effort, numerical models are being developed to predict TNT transport in soils including the effect of precipitation and evaporation. Modifications will be made to TOUGH2 for application to the TNT chemical sensing problem. Understanding the fate and transport of TNT in the soil will affect the design, performance and operation of chemical sensors by indicating preferred sensing strategies.

Webb, S.W.; Phelan, J.M. [Sandia National Labs., Albuquerque, NM (United States); Finsterle, S.A.; Pruess, K. [Lawrence Berkeley National Lab., CA (United States)

1998-06-01

172

Gravitational Horizon(3)  

NASA Astrophysics Data System (ADS)

Anomalous decelerations of spacecraft Pioneer-10,11,etc could be interpreted as signal delay effect between speed of gravity and that of light as reflected in virtual scale, similar to covarying virtual scale effect in relative motion (http://arxiv.org/html/math-ph/0001019v5).A finite speed of gravity faster than light could be inferred (http://arXiv.org/html/physics/0001034v2). Measurements of gravitational variations by paraconical pendulum during a total solar eclipse infer the same(http://arXiv.org/html/physics/0001034v9). A finite Superluminal speed of gravity is the necessary condition to imply that there exists gravitational horizon (GH). Such "GH" of our Universe would stretch far beyond the cosmic event horizon of light. Dark energy may be owing to mutually interactive gravitational horizons of cousin universes. Sufficient condition for the conjecture is that the dark energy would be increasing with age of our Universe since accelerated expansion started about 5 Gyr ago, since more and more arrivals of "GH" of distant cousin universes would interact with "GH" of our Universe. The history of dark energy variations between then and now would be desirable(http://arXiv.org/html/physics/0001034). In "GH" conjecture, the neighborhood of cousin universes would be likely boundless in 4D-space-time without begining or end. The dark energy would keep all universes in continually accelerated expansion to eventual fragmentation. Fragments would crash and merge into bangs, big or small, to form another generation of cousin universes. These scenarios might offer a clue to what was before the big bang.

Yang, Chao Yuan

2012-05-01

173

Degradation of carbohydrates and lignins in buried woods  

USGS Publications Warehouse

Spruce, alder, and oak woods deposited in coastal sediments were characterized versus their modern counterparts by quantification of individual neutral sugars and lignin-derived phenols as well as by scanning electron microscopy, 13C NMR, and elemental analysis. The buried spruce wood from a 2500 yr old deposit was unaltered whereas an alder wood from the same horizon and an oak wood from an open ocean sediment were profoundly degraded. Individual sugar and lignin phenol analyses indicate that at least 90 and 98 wt% of the initial total polysaccharides in the buried alder and oak woods, respectively, have been degraded along with 15-25 wt% of the lignin. At least 75% of the degraded biopolymer has been physically lost from these samples. This evidence is supported by the SEM, 13C NMR and elemental analyses, all of which indicate selective loss of the carbohydrate moiety. The following order of stability was observed for the major biochemical constituents of both buried hardwoods: vanillyl and p-hydroxyl lignin structural units > syringyl lignin structural units > pectin > ??-cellulose > hemicellulose. This sequence can be explained by selective preservation of the compound middle lamella regions of the wood cell walls. The magnitude and selectivity of the indicated diagenetic reactions are sufficient to cause major changes in the chemical compositions of wood-rich sedimentary organic mixtures and to provide a potentially large in situ nutrient source. ?? 1985.

Hedges, J. I.; Cowie, G. L.; Ertel, J. R.; James, Barbour, R.; Hatcher, P. G.

1985-01-01

174

Sensor system for buried waste containment sites  

DOEpatents

A sensor system is disclosed for a buried waste containment site having a bottom wall barrier and/or sidewall barriers, for containing hazardous waste. The sensor system includes one or more sensor devices disposed in one or more of the barriers for detecting a physical parameter either of the barrier itself or of the physical condition of the surrounding soils and buried waste, and for producing a signal representing the physical parameter detected. Also included is a signal processor for receiving signals produced by the sensor device and for developing information identifying the physical parameter detected, either for sounding an alarm, displaying a graphic representation of a physical parameter detected on a viewing screen and/or a hard copy printout. The sensor devices may be deployed in or adjacent the barriers at the same time the barriers are deployed and may be adapted to detect strain or cracking in the barriers, leakage of radiation through the barriers, the presence and leaking through the barriers of volatile organic compounds, or similar physical conditions.

Smith, Ann Marie (Pocatello, ID); Gardner, Bradley M. (Idaho Falls, ID); Kostelnik, Kevin M. (Idaho Falls, ID); Partin, Judy K. (Idaho Falls, ID); Lancaster, Gregory D. (Idaho Falls, ID); Pfeifer, May Catherine (Idaho Falls, ID)

2000-01-01

175

Buried oxide layer in silicon  

DOEpatents

A process for forming Silicon-On-Insulator is described incorporating the steps of ion implantation of oxygen into a silicon substrate at elevated temperature, ion implanting oxygen at a temperature below 200.degree. C. at a lower dose to form an amorphous silicon layer, and annealing steps to form a mixture of defective single crystal silicon and polycrystalline silicon or polycrystalline silicon alone and then silicon oxide from the amorphous silicon layer to form a continuous silicon oxide layer below the surface of the silicon substrate to provide an isolated superficial layer of silicon. The invention overcomes the problem of buried isolated islands of silicon oxide forming a discontinuous buried oxide layer.

Sadana, Devendra Kumar (Pleasantville, NY); Holland, Orin Wayne (Lenoir, TN)

2001-01-01

176

Thin film buried anode battery  

DOEpatents

A reverse configuration, lithium thin film battery (300) having a buried lithium anode layer (305) and process for making the same. The present invention is formed from a precursor composite structure (200) made by depositing electrolyte layer (204) onto substrate (201), followed by sequential depositions of cathode layer (203) and current collector (202) on the electrolyte layer. The precursor is subjected to an activation step, wherein a buried lithium anode layer (305) is formed via electroplating a lithium anode layer at the interface of substrate (201) and electrolyte film (204). The electroplating is accomplished by applying a current between anode current collector (201) and cathode current collector (202).

Lee, Se-Hee (Lakewood, CO); Tracy, C. Edwin (Golden, CO); Liu, Ping (Denver, CO)

2009-12-15

177

Resolving Lifshitz Horizons  

SciTech Connect

Via the AdS/CFT correspondence, ground states of field theories at finite charge density are mapped to extremal black brane solutions. Studies of simple gravity + matter systems in this context have uncovered wide new classes of extremal geometries. The Lifshitz metrics characterizing field theories with non-trivial dynamical critical exponent z {ne} 1 emerge as one common endpoint in doped holographic toy models. However, the Lifshitz horizon exhibits mildly singular behaviour - while curvature invariants are finite, there are diverging tidal forces. Here we show that in some of the simplest contexts where Lifshitz metrics emerge, Einstein-Maxwell-dilaton theories, generic corrections lead to a replacement of the Lifshitz metric, in the deep infrared, by a re-emergent AdS{sub 2} x R{sup 2} geometry. Thus, at least in these cases, the Lifshitz scaling characterizes the physics over a wide range of energy scales, but the mild singularity is cured by quantum or stringy effects.

Harrison, Sarah; Kachru, Shamit; Wang, Huajia; /Stanford U., ITP /Stanford U., Phys. Dept. /SLAC

2012-04-24

178

Gravitational Horizon (2)  

NASA Astrophysics Data System (ADS)

The anomalous deceleration of spacecraft Pioneer 10,11,etc could be interpreted as signal delay effect reflected in virtual scale, in analogy to a scale conversion in relative motion between the co-varying virtual and the invariant real scales( http://arxiv.org/html/math-ph/0001019v5). A finite speed of gravity faster than light was implied ( http://arXiv.org/html/physics/0001034v2 ). A lower limit for a speed of gravity was derived by pluging in the ratio of nominal to anomalous decelerations via scale conversion ( http://arXiv.org/html/physics/0001034 ). Here we suggest a few possible ways including some astronomical events of planetary alignments. If we can measure the precise time of the event in gravitational effect, and that of the equivalent optical effect, then through time difference between these two effects for the same event we may derive speed of gravity. A ball-borne pendulum seems to be a good instrument to serve for this purpose in the well defined gravitational variation in azimuthal precession during Sun-Mercury-Earth conjunction. A directly measured speed of gravity faster than light is the necessary condition to infer that there exists a gravitational horizon. Dark energy may be owing to mutually interactive gravitational horizons of neighbors in the neighborhood of universes.Our Universe may not be alone.The sufficient condition for this conjecture is that the dark energy would be increasing with the age of Universe. ( http://cyyang.multiply.com/journal/item/2/geo_astronomers_home_ )

Yang, Chao Yuan; Li, J.; Olenici, D.

2010-01-01

179

The New Horizons Spacecraft  

NASA Astrophysics Data System (ADS)

The New Horizons spacecraft was launched on 19 January 2006. The spacecraft was designed to provide a platform for seven instruments designated by the science team to collect and return data from Pluto in 2015. The design meets the requirements established by the National Aeronautics and Space Administration (NASA) Announcement of Opportunity AO-OSS-01. The design drew on heritage from previous missions developed at The Johns Hopkins University Applied Physics Laboratory (APL) and other missions such as Ulysses. The trajectory design imposed constraints on mass and structural strength to meet the high launch acceleration consistent with meeting the AO requirement of returning data prior to the year 2020. The spacecraft subsystems were designed to meet tight resource allocations (mass and power) yet provide the necessary control and data handling finesse to support data collection and return when the one-way light time during the Pluto fly-by is 4.5 hours. Missions to the outer regions of the solar system (where the solar irradiance is 1/1000 of the level near the Earth) require a radioisotope thermoelectric generator (RTG) to supply electrical power. One RTG was available for use by New Horizons. To accommodate this constraint, the spacecraft electronics were designed to operate on approximately 200 W. The travel time to Pluto put additional demands on system reliability. Only after a flight time of approximately 10 years would the desired data be collected and returned to Earth. This represents the longest flight duration prior to the return of primary science data for any mission by NASA. The spacecraft system architecture provides sufficient redundancy to meet this requirement with a probability of mission success of greater than 0.85. The spacecraft is now on its way to Pluto, with an arrival date of 14 July 2015. Initial in-flight tests have verified that the spacecraft will meet the design requirements.

Fountain, Glen H.; Kusnierkiewicz, David Y.; Hersman, Christopher B.; Herder, Timothy S.; Coughlin, Thomas B.; Gibson, William C.; Clancy, Deborah A.; Deboy, Christopher C.; Hill, T. Adrian; Kinnison, James D.; Mehoke, Douglas S.; Ottman, Geffrey K.; Rogers, Gabe D.; Stern, S. Alan; Stratton, James M.; Vernon, Steven R.; Williams, Stephen P.

2008-10-01

180

Markov Games: Receding Horizon Approach.  

National Technical Information Service (NTIS)

The authors consider a receding horizon approach as an approximate solution to two-person, zero-sum Markov games with infinite horizon discounted cost and average cost criteria. They first present error bounds from the optimal equilibrium value of the gam...

H. S. Chang S. I. Marcus

2001-01-01

181

The Horizon Report. 2007 Edition  

ERIC Educational Resources Information Center

|This fourth edition of the New Media Consortium's (NMC) annual "Horizon Report" describes the continuing work of the Horizon Project, a research-oriented effort that seeks to identify and describe emerging technologies likely to have a large impact on teaching, learning, or creative expression within higher education. Drawing on ongoing…

New Media Consortium, 2007

2007-01-01

182

Common causes of material degradation in buried piping  

SciTech Connect

Buried pipe may fail for innumerable reasons. Causes can be mechanical damage/breakage, chemically initiated corrosion, or a combination. Failures may originate either internally or externally on the pipe. They may be related to flaws in the design, to excessive or unanticipated internal pressure or ground level loading, and/or to poor or uncertain installation practice. Or the pipe may simply ``wear out`` in service. Steel is strong and very forgiving in underground applications, especially with regard to backfill. However, soil support developed through densification or compaction is critical for brittle concrete and vitrified clay tile pipe, and is very important for cast iron and plastic pipe. Chemistry of the soil determines whether or not it will enhance corrosion or other types of degradation. Various causes and mechanisms for deterioration of buried pipe are indicated. Some peculiarities of the different materials of construction are characterized. Repair methods and means to circumvent special problems are described.

Jenkins, C.F.

1997-01-20

183

Effect of Antiseptics on Soil Microflora During Soil Burial Testing.  

National Technical Information Service (NTIS)

Specific ecological conditions are created in soil containing antiseptics, which determine the nature of the microflora which develop. Examination of soil surrounding buried antiseptic-treated wood has revealed that the toxicity of antiseptics is maximal ...

I. A. Petrenko

1969-01-01

184

Overhead and buried conductor system  

Microsoft Academic Search

In this paper a novel computer code for the analysis of both aerial and buried system of conductors in wide frequency range is presented. A hybrid approach has been applied enabling incorporation into a single linear system both lumped circuit parameters and distributed parameters evaluated through a rigorous electromagnetic field analysis. The system of discretised conductors is replaced by a

R. Andolfato; L. Bernardi; L. Fellin

1998-01-01

185

UHF Propagation from Buried Antennas.  

National Technical Information Service (NTIS)

The paper poses, and attempts to answer, some of the questions involved when a UHF antenna is buried in the ground. A description of the basic theory is given, together with illustrative calculations for many situations of interest. Graphs are presented f...

G. A. Hufford

1969-01-01

186

Locating a Buried Magnetic Dipole  

Microsoft Academic Search

Five measurements of the magnetic-field vector near the surface of the earth are shown to be sufficient to determine the orientation and location of a buried magnetic dipole. A discussion of field experiments which demonstrate the location concept is included.

Thurlow W. H. Caffey; Louis Romero

1982-01-01

187

Performance of buried flexible conduits  

Microsoft Academic Search

An extensive review was made of the performance of buried flexible culverts, with special emphasis on buckling failure modes. All known theories on elastic buckling of rings and cylinders with radial support subjected to external radial pressures were analyzed and compared with each other, and with the results of controlled experiments on small and full-scale culverts. Some relevant field measurements

G. A. Leonards; R. A. Stetkar

1978-01-01

188

Test plan for buried waste containment system materials  

SciTech Connect

The objectives of the FY 1997 barrier material work at the Idaho National Engineering and Environmental Laboratory are to (1) select a waste barrier material and verify that it is compatible with the Buried Waste Containment System Process, and (2) determine if, and how, the Buried Waste Containment System emplacement process affects the material properties and performance (on proof of principle scale). This test plan describes a set of measurements and procedures used to validate a waste barrier material for the Buried Waste Containment System. A latex modified proprietary cement manufactured by CTS Cement Manufacturing Company will be tested. Emplacement properties required for the Buried Waste Containment System process are: slump between 8 and 10 in., set time between 15 and 30 minutes, compressive strength at set of 20 psi minimum, and set temperature less than 100{degrees}C. Durability properties include resistance to degradation from carbonate, sulfate, and waste-site soil leachates. A set of baseline barrier material properties will be determined to provide a data base for comparison with the barrier materials when tested in the field. The measurements include permeability, petrographic analysis to determine separation and/or segregation of mix components, and a set of mechanical properties. The measurements will be repeated on specimens from the field test material. The data will be used to determine if the Buried Waste Containment System equipment changes the material. The emplacement properties will be determined using standard laboratory procedures and instruments. Durability of the barrier material will be evaluated by determining the effect of carbonate, sulfate, and waste-site soil leachates on the compressive strength of the barrier material. The baseline properties will be determined using standard ASTM procedures. 9 refs., 1 fig., 2 tabs.

Weidner, J.; Shaw, P.

1997-03-01

189

In situ vitrification on buried waste  

Microsoft Academic Search

In situ vitrification (ISV) is being evaluated as a remedial treatment technology for buried mixed and transuranic (TRU) wastes at the Subsurface Disposal Area (SDA) at Idaho National Engineering Laboratory (INEL) and can be related to buried wastes at other Department of Energy (DOE) sites. There are numerous locations around the DOE Complex where wastes were buried in the ground

1992-01-01

190

Mechanics of rotating isolated horizons  

SciTech Connect

Black hole mechanics was recently extended by replacing the more commonly used event horizons in stationary space-times with isolated horizons in more general space-times (which may admit radiation arbitrarily close to black holes). However, so far the detailed analysis has been restricted to nonrotating black holes (although it incorporated arbitrary distortion, as well as electromagnetic, Yang-Mills, and dilatonic charges). We now fill this gap by first introducing the notion of isolated horizon angular momentum and then extending the first law to the rotating case.

Ashtekar, Abhay; Beetle, Christopher; Lewandowski, Jerzy

2001-08-15

191

Technology status report: In situ vitrification applied to buried wastes  

SciTech Connect

This document is a technical status report on In Situ Vitrification (ISV) as applied to buried waste; the report takes both technical and institutional concerns into perspective. The ISV process involves electrically melting such contaminated solid media as soil, sediment, sludge, and mill tailings. The resultant product is a high-quality glass-and-crystalline waste form that possesses high resistance to corrosion and leaching and is capable of long-term environmental exposure without significant degradation. The process also significantly reduces the volume of the treated solid media due to the removal of pore spaces in the soil.

Thompson, L.E. [Pacific Northwest Lab., Richland, WA (United States); Bates, S.O. [EG and G Idaho, Inc., Idaho Falls, ID (United States); Hansen, J.E. [Geosafe Corp., Richland, WA (United States)

1992-09-01

192

Numerical Model for Predicting Two Dimensional Infiltrations and Solute Travel Time in Heterogeneous Layered Soil  

Microsoft Academic Search

Field soils are usually composed of at least two horizons. Different than independent geological layers, soil horizons are spatially dependent on each other as they were formed under pedogenic process acting on the same parent material. Dyck (2008) tested the influence of soil horizon on the hydraulic behavior of the entire soil profile and found that the influence is scale

Y. S. Song; G. Kachanoski; M. F. Dyck

2010-01-01

193

New horizons in osteoarthritis.  

PubMed

Osteoarthritis (OA), also known as degenerative joint disease, is the most frequent chronic musculoskeletal disease and the leading cause of disability in elderly persons. There are currently at least 27 million persons afflicted with OA in the United States, and the annual cost to society in medical care and wage loss is expected to reach nearly $100 billion dollars by 2020, with consequent increased spending on its diagnosis and treatment, side effect prevention, and loss of productivity. Despite this enormous burden, many aspects of OA are still unknown, with implications not only in terms of diagnosis and assessment but also with regard to therapy. Awareness of this state of affairs has attracted many researchers to this field, making OA one of the most actively studied sectors of rheumatology. Although some clinicians are unaware of recent advances, there is a large body of publications indicating that much has been achieved. Major progress has been made in formulating better definitions of risk factors, in particular in indicating the responsibility of biomechanical and genetic factors, and, with regard to pathogenesis, underlining the role of subchondral bone, cytokines and proteinases. Assessment of OA activity and its progression has been improved with the advent of biomarkers and new imaging procedures, in particular sonography and magnetic resonance imaging (MRI), but also of better clinical instruments, including more reliable patient questionnaires. Information from ongoing studies may improve the to some extent incomplete definition of OA phenotypes. Finally, promising new horizons have been opened up even with regard to the treatment of OA, which is still for the most part unsatisfactory except for surgical replacement therapy. Numerous new substances have been formulated and the findings of trials studying their effects are encouraging, although much has yet to be done. PMID:20458653

Oliviero, F; Ramonda, R; Punzi, L

2010-09-17

194

Odor analysis of decomposing buried human remains  

SciTech Connect

This study, conducted at the University of Tennessee's Anthropological Research Facility (ARF), lists and ranks the primary chemical constituents which define the odor of decomposition of human remains as detected at the soil surface of shallow burial sites. Triple sorbent traps were used to collect air samples in the field and revealed eight major classes of chemicals which now contain 478 specific volatile compounds associated with burial decomposition. Samples were analyzed using gas chromatography-mass spectrometry (GC-MS) and were collected below and above the body, and at the soil surface of 1.5-3.5 ft. (0.46-1.07 m) deep burial sites of four individuals over a 4-year time span. New data were incorporated into the previously established Decompositional Odor Analysis (DOA) Database providing identification, chemical trends, and semi-quantitation of chemicals for evaluation. This research identifies the 'odor signatures' unique to the decomposition of buried human remains with projected ramifications on human remains detection canine training procedures and in the development of field portable analytical instruments which can be used to locate human remains in shallow burial sites.

Vass, Arpad Alexander [ORNL; Smith, Rob R [ORNL; Thompson, Cyril V [ORNL; Burnett, Michael N [ORNL; Dulgerian, Nishan [ORNL; Eckenrode, Brian A [ORNL

2008-01-01

195

Odor analysis of decomposing buried human remains.  

PubMed

This study, conducted at the University of Tennessee's Anthropological Research Facility (ARF), lists and ranks the primary chemical constituents which define the odor of decomposition of human remains as detected at the soil surface of shallow burial sites. Triple sorbent traps were used to collect air samples in the field and revealed eight major classes of chemicals which now contain 478 specific volatile compounds associated with burial decomposition. Samples were analyzed using gas chromatography-mass spectrometry (GC-MS) and were collected below and above the body, and at the soil surface of 1.5-3.5 ft. (0.46-1.07 m) deep burial sites of four individuals over a 4-year time span. New data were incorporated into the previously established Decompositional Odor Analysis (DOA) Database providing identification, chemical trends, and semi-quantitation of chemicals for evaluation. This research identifies the "odor signatures" unique to the decomposition of buried human remains with projected ramifications on human remains detection canine training procedures and in the development of field portable analytical instruments which can be used to locate human remains in shallow burial sites. PMID:18366571

Vass, Arpad A; Smith, Rob R; Thompson, Cyril V; Burnett, Michael N; Dulgerian, Nishan; Eckenrode, Brian A

2008-03-01

196

HORIZON SENSING (PROPOSAL No.51)  

SciTech Connect

Real-time horizon sensing on continuous mining machines is becoming an industry tool. Installation and testing of production-grade HS systems has been ongoing this quarter at Monterey Coal Company (EXXON), FMC Trona, Twentymile Coal Company (RAG America), and SASOL Coal. Detailed monitoring of system function, user experience, and mining benefits is ongoing. All horizon sensor components have finished MSHA (U.S.) and IEC (International) certification.

Larry G. Stolarczyk, Sc.D.

2002-04-30

197

Physicochemical and mineralogical diagnostic features of solonetzic process in soils of the Lower Volga region in the late holocene  

NASA Astrophysics Data System (ADS)

Modern solonetzes and paleosolonetzes buried under steppe kurgans 3800-600 years ago were studied in the Lower Volga region. Overall, 28 quantitative parameters used in the description of the solonetzic process were examined. These parameters included the textural (the clay content, the ratio of the clay (<0.001 mm) content in the B horizon to that in the A horizon, the degree of the textural differentiation of the profile, the degree of illuviation of the profile, the content of particles <0.005 mm, and the particle size of clay minerals) and the physicochemical and mineralogical (the cation exchange capacity; the contents of exchangeable Na, Mg, and Ca; the contents of soluble salts, smectites, hydromica, and fine-dispersed quartz particles; the specific surface area; the contents of elements in the bulk soil samples and in the clay fraction; the Al/(K + Ca + Na + Mg) and SiO2/R2O3 ratios; the morphology of sand-size quartz particles; the magnetic susceptibility of the soils; etc.) characteristics. It was shown that the studied soils are characterized by different intensities of the solonetzic process. The asynchronous development of solonetzes in the Lower Volga region and the polygenetic nature of these soils may be the reasons for the absence of a correlation between the degree of manifestation of solonetzic features in the soils and the soil age.

Alekseeva, T. V.; Alekseev, A. O.; Demkin, V. A.; Alekseeva, V. A.; Sokolowska, Z.; Hajnos, M.; Kalinin, P. I.

2010-10-01

198

Time as An Important Soil-Forming Factor Influencing Modern and Ancient Magnetic Susceptibility Enhancement Along the Delaware River Valley, USA  

NASA Astrophysics Data System (ADS)

Magnetic susceptibility is an increasingly popular low-cost method for rapidly assessing paleoclimate and paleoenvironmental impact on buried soils. The goal of this study is to determine the primary influence(s) on soil magnetic susceptibility along floodplain, terrace and upland soils in the middle Delaware River Valley, USA, using environmental magnetic, pedologic, and stratigraphic techniques. Two-hundred thirty samples were collected from age-constrained sandy, quartz-rich, floodplain, terrace, and upland soils (Entisols, Inceptisols). A Kruskal-Wallis (K-W) and post-hoc Tukey-Kramer (T-K) (?=0.05) multiple comparisons analysis on 176 mass-specific low-field susceptibility (Xlf) assays show that A and B horizons are magnetically enhanced compared to C and E horizons (p<0.0001). Results of descriptive soil micromorphology show that A and B horizons contain anywhere from 10-50% more amorphous organic matter and clay films along pores than do C and E horizons. Enhanced Xlf values also correlate positively (R^2=0.63) with the soil molecular weathering ratio of Alumina/Bases, suggesting that increased weathering likely results in the formation of pedogenic magnetic minerals and enhanced magnetic susceptibility signal. Additional K-W and T-K testing show that Xlf results, when grouped by floodplain-terrace designation (i.e., chronofunction) are significantly different (p<0.0001). The older T3 terrace and upland Xlf values (0.34±0.14 10^-6 m^3 kg^-1) are greater than the younger T2 terrace (0.18±0.06 10^-6 m^3 kg^-1) values, which are greater than modern floodplain (0.09±0.01 10^-6 m^3 kg^-1) Xlf values. These data suggest that longer intervals of soil formation enhance the ?lf value. This hypothesis is further supported when 159 Xlf values are plotted vs. age for the entire Holocene. A locally-weighted regression smoothing curve (LOESS) shows two distinct intervals of magnetic enhancement during previously established dry intervals, the early and late-middle Holocene. We hypothesize that prolonged drought during the early and middle Holocene reduced flood frequency and magnitude and the likelihood of soil burial, resulting in longer soil forming intervals and higher Xlf values. Although precipitation influences the Xlf signature, the results from this study suggest that the magnetic susceptibility values of well-drained buried floodplain soils along the Delaware River Valley are partly a function of time.

Stinchcomb, G. E.; Peppe, D. J.; Driese, S. G.

2011-12-01

199

Electromagnetic response of buried cylindrical structures for line current excitation  

NASA Astrophysics Data System (ADS)

The Cylindrical-Wave Approach (CWA) rigorously solves, in the spectral domain, the electromagnetic forward scattering by a finite set of buried two-dimensional perfectly-conducting or dielectric objects [1]-[2]. In this technique, the field scattered by underground objects is represented in terms of a superposition of cylindrical waves. Use is made of the plane-wave spectrum [1] to take into account the interaction of such waves with the planar interface between air and soil, and between different layers eventually present in the ground [3]. Obstacles of general shape can be simulated through the CWA with good results, by using a suitable set of small circular-section cylinders [4]. Recently, we improved the CWA by facing the fundamental problem of losses in the ground [5]: this is of significant importance in remote-sensing applications, since real soils often have complex permittivity and conductivity, and sometimes also a complex permeability. While in previous works concerning the CWA a monochromatic or pulsed plane-wave incident field was considered, in the present work a different source of scattering is present: a cylindrical wave radiated by a line source. Such a source is more suitable to model the practical illumination field used in GPR surveys. The electric field radiated by the line current is expressed by means of a first-kind Hankel function of 0-th order. The theoretical solution to the scattering problem is developed for both dielectric and perfectly-conducting cylinders buried in a dielectric half-space. The approach is implemented in a Fortran code; an accurate numerical evaluation of the involved spectral integrals is performed, the highly-oscillating behavior of the homogeneous waves is correctly followed and evanescent contributions are taken into account. The electromagnetic field scattered in both air and ground can be obtained, in near- and far-field regions, for arbitrary radii and permittivity of the buried cylinders, as well as for arbitrary arrangements of cylinders in the soil. As future work, the presented analysis, carried out in the spectral domain, will be extended to a time-domain solution following an approach analogous to the one developed in [6] for pulsed plane-wave excitation. [1] M. Di Vico, F. Frezza, L. Pajewski, and G. Schettini, "Scattering by a Finite Set of Perfectly Conducting Cylinders Buried in a Dielectric Half-Space: a Spectral-Domain Solution," IEEE Transactions Antennas and Propagation, vol. 53(2), 719-727, 2005. [2] M. Di Vico, F. Frezza, L. Pajewski, and G. Schettini, "Scattering by Buried Dielectric Cylindrical Structures," Radio Science, vol. 40(6), RS6S18, 2005. [3] F. Frezza, L. Pajewski, C. Ponti, and G. Schettini, "Scattering by Perfectly-Conducting Cylinders Buried in a Dielectric Slab through the Cylindrical Wave Approach," IEEE Transactions Antennas and Propagation, vol. 57(4), 1208-1217, 2009. [4] F. Frezza, L. Pajewski, C. Ponti, and G. Schettini, "Accurate Wire-Grid Modeling of Buried Conducting Cylindrical Scatterers," Nondestructive Testing and Evaluation (Special Issue on "Civil Engineering Applications of Ground Penetrating Radar"), vol. 27(3), pp. 199-207, 2012. [5] F. Frezza, L. Pajewski, C. Ponti, G. Schettini, and N. Tedeschi, "Electromagnetic Scattering by a Metallic Cylinder Buried in a Lossy Medium with the Cylindrical Wave Approach," IEEE Geoscience and Remote Sensing Letters, vol. 10(1), pp. 179-183, 2013. [6] F. Frezza, P. Martinelli, L. Pajewski, and G. Schettini, "Short-Pulse Electromagnetic Scattering from Buried Perfectly-Conducting Cylinders," IEEE Geoscience and Remote Sensing Letters, vol. 4(4), pp. 611-615, 2007.

Pajewski, Lara; Ponti, Cristina

2013-04-01

200

Soil  

NSDL National Science Digital Library

Soil is an example of a non-living thing. Soil contains nutrients and living organisms, but the soil itself is not alive. Soil is important in plant growth because soil gives plants a place to anchor their roots and it also provides the plant with essential nutrients.

Scott Bauer (USDA-ARS;)

2006-05-23

201

Centrifuge modeling of PGD response of buried pipe  

NASA Astrophysics Data System (ADS)

A new centrifuge based method for determining the response of continuous buried pipe to PGD is presented. The physical characteristics of the RPI's 100 g-ton geotechnical centrifuge and the current lifeline experiment split-box are described: The split-box contains the model pipeline and surrounding soil and is manufactured such that half can be offset, in flight, simulating PGD. In addition, governing similitude relations which allow one to determine the physical characteristics, (diameter, wall thickness and material modulus of elasticity) of the model pipeline are presented. Finally, recorded strains induced in two buried pipes with prototype diameters of 0.63 m and 0.95 m (24 and 36 inch) subject to 0.6 and 2.0 meters (2 and 6 feet) of full scale fault offsets and presented and compared to corresponding FE results.

O'Rourke, Michael; Gadicherla, Vikram; Abdoun, Tarek

2005-06-01

202

In situ grouting of buried transuranic waste with polyacrylamide  

SciTech Connect

This project is a demonstration and evaluation of the in situ hydrologic stabilization of buried transuranic waste at a humid site via grout injection. Two small trenches, containing buried transuranic waste, were filled with 34.000 L of polyacrylamide grout. Initial field results have indicated that voids within the trenches were totally filled by the grout and that the intratrench hydraulic conductivity was reduced to below field-measurable values. No evidence of grout constituents were observed in twelve perimeter groundwater monitoring wells indicating that grout was contained completely within the two trenches. Polyacrylamide grout was selected for field demonstration over the polyacrylate grout due to its superior performance in laboratory degradation studies. Also supporting the selection of polyacrylamide was the difficulty in controlling the set time of the acrylate polymerization. Based on preliminary degradation monitoring, the polyacrylamide was estimated to have a microbiological half-life of 362 years in the test soil. 15 refs., 9 figs., 12 tabs.

Spalding, B.P.; Lee, S.Y.; Farmer, C.D.; Hyder, L.K.; Supaokit, P.

1987-01-01

203

Genesis of pedons with discontinuous argillic horizons in the Holocene loess mantle of the southern Pampean landscape, Argentina  

NASA Astrophysics Data System (ADS)

Soil development in the plain landscape of the southern Argentinean Pampa is related to pulses of aeolian accretion of calcareous loess during the Holocene epoch. Such plain relief is associated with landform stability that favors pedogenesis. In some sectors of the Holocene loess mantle, detailed soil surveys show a great variability of soil morphology in short distances (<7 m), such that pedons with Bt horizon (Ap-Bt-C-2Ckm) coexist with pedons with an AC horizon (Ap-AC-C-2Ckm) in a plain landscape, within identical loess parent material over a tosca layer (2Ckm-calcrete-petrocalcic horizon), and in a similar pedoclimate. This article studies the origin of this spatial variation. Loess parent materials directly overlie the relic tosca layer, exhumed after erosion of preexisting soils of the Late Pleistocene. The contrast in soil morphology between the petrocalcic horizon and the overlying Holocene soils reflects the effect of polygenesis. The complex soil spatial distribution pattern over the tosca layer appears unrelated to its paleomicrotopography, because soils with Bt horizons are identified in positive and depressed microlandforms of the tosca. The absence of Bt horizons might be caused by formerly intense biological activity related to a stable pattern of two natural vegetation covers or a surface paleomicrotopography that supported distinct vegetation types depending on the soil moisture in each paleomicrolandform.

Blanco, M. Del C.; Stoops, G.

2007-01-01

204

A study of the effect of buried biomass on ground-penetrating radar performance  

NASA Astrophysics Data System (ADS)

It is widely acknowledged that tree roots and other forms of buried biomass have an adverse effect on the performance of ground-penetrating radars (GPRs). In this work we present experimental and theoretical work that quantifies that effect. Test sites containing extensive root infiltration at Eglin Air Force Base, FL were probed with a GPR. After completing the measurements, the sites were excavated, and the root structure and soil were thoroughly characterized. Supplemental GPR measurements of simple cylindrical objects in a laboratory setting were performed to investigate the basic scattering behavior of buried roots. A numerical simulator based on the Discrete Dipole Approximation (DDA), an integral-equation-based method, was developed, validated and subsequently used to compute scattering from root structures modeled by an ensemble of buried cylinders. A comparison of the measurements and numerical calculations is presented that quantifies the potential for false alarms and increased clutter due to buried roots.

Niltawach, Nakasit; Chen, Chi-Chih; Johnson, Joel T.; Baertlein, Brian A.

2003-08-01

205

BATATA: a buried muon hodoscope  

SciTech Connect

Muon hodoscopes have several applications, ranging from astrophysics to fundamental particle physics. In this work, we present a detector dedicated to the study, at ground level, of the main signals of cosmic-ray induced showers above 6 PeV. The whole detector is composed by a set of three parallel dual-layer scintillator planes buried at fix depths ranging from 120 g/cm{sup 2} to 600 g/cm{sup 2} and by a triangular array of water cerenkov detectors located nearby on ground.

Sanchez, F.; Supanitsky, A. D.; Medina-Tanco, G.; Paic, G.; Salazar, M. E. Patino; D'Olivo, J. C. [Departamento de Fisica de Altas Energias, Instituto de Ciencias Nucleares, Universidad Nacional Autonoma de Mexico, A. P. 70-543, 04510, Mexico, D. F. (Mexico); Molina, R. Alfaro [Instituto de Fisica, Universidad Nacional Autonoma de Mexico, A. P. 70-543, 04510, Mexico, D. F. (Mexico)

2009-04-20

206

Buried Waste Integrated Demonstration Plan  

SciTech Connect

This document presents the plan of activities for the Buried Waste Integrated Demonstration (BWID) program which supports the environmental restoration (ER) objectives of the Department of Energy (DOE) Complex. Discussed in this plan are the objectives, organization, roles and responsibilities, and the process for implementing and managing BWID. BWID is hosted at the Idaho National Engineering Laboratory (INEL), but involves participants from throughout the DOE Complex, private industry, universities, and the international community. These participants will support, demonstrate, and evaluate a suite of advanced technologies representing a comprehensive remediation system for the effective and efficient remediation of buried waste. The processes for identifying technological needs, screening candidate technologies for applicability and maturity, selecting appropriate technologies for demonstration, field demonstrating, evaluation of results and transferring technologies to environmental restoration programs are also presented. This document further describes the elements of project planning and control that apply to BWID. It addresses the management processes, operating procedures, programmatic and technical objectives, and schedules. Key functions in support of each demonstration such as regulatory coordination, safety analyses, risk evaluations, facility requirements, and data management are presented.

Kostelnik, K.M.

1991-12-01

207

Generic isolated horizons in loop quantum gravity  

NASA Astrophysics Data System (ADS)

Isolated horizons model equilibrium states of classical black holes. A detailed quantization, starting from a classical phase space restricted to spherically symmetric horizons, exists in the literature and has since been extended to axisymmetry. This paper extends the quantum theory to horizons of arbitrary shape. Surprisingly, the Hilbert space obtained by quantizing the full phase space of all generic horizons with a fixed area is identical to that originally found in spherical symmetry. The entropy of a large horizon remains one-quarter its area, with the Barbero-Immirzi parameter retaining its value from symmetric analyses. These results suggest a reinterpretation of the intrinsic quantum geometry of the horizon surface.

Beetle, Christopher; Engle, Jonathan

2010-12-01

208

Redistribution of soil nitrogen, carbon and organic matter by mechanical disturbance during whole-tree harvesting in northern hardwoods  

USGS Publications Warehouse

To investigate whether mechanical mixing during harvesting could account for losses observed from forest floor, we measured surface disturbance on a 22 ha watershed that was whole-tree harvested. Surface soil on each 10 cm interval along 81, randomly placed transects was classified immediately after harvesting as mineral or organic, and as undisturbed, depressed, rutted, mounded, scarified, or scalped (forest floor scraped away). We quantitatively sampled these surface categories to collect soil in which preharvest forest floor might reside after harvest. Mechanically mixed mineral and organic soil horizons were readily identified. Buried forest floor under mixed mineral soil occurred in 57% of mounds with mineral surface soil. Harvesting disturbed 65% of the watershed surface and removed forest floor from 25% of the area. Mechanically mixed soil under ruts with organic or mineral surface soil, and mounds with mineral surface soil contained organic carbon and nitrogen pools significantly greater than undisturbed forest floor. Mechanical mixing into underlying mineral soil could account for the loss of forest floor observed between the preharvest condition and the second growing season after whole-tree harvesting. ?? 1992.

Ryan, D. F.; Huntington, T. G.; Wayne, Martin, C.

1992-01-01

209

Common Ground: Expanding Our Horizons.  

ERIC Educational Resources Information Center

In "Common Ground: Dialogue, Understanding, and the Teaching of Composition," Kurt Spellmeyer seeks to familiarize students and teachers with the linguistic and cultural no-man's-land separating them. Reinstating the value of two writing conventions often used by traditional students--expressive and commonplaces--can help expand on the horizons of…

McDevitt, Michele J.

210

Joint breeding in female burying beetles  

Microsoft Academic Search

Summary Burying beetles (Nicrophorus) exhibit advanced parental care, by feeding and guarding their offspring on buried vertebrate carrion. Till now, interactions between two conspecific females on a carcass have been thought to be mostly competitive, and parental care was thought to be provided by single females or male-female pairs exclusively. Here we demonstrate that cooperative brood care occurs in this

Anne-Katrin Eggert; Josef K. Miiller

1992-01-01

211

Seismic risk analysis of buried pipelines--  

Microsoft Academic Search

A procedure is described for the seismic risk analysis of buried pipelines that provides an estimation of the annual probability of occurrence of different damage states, called damage indexes, in a component segment of the general network system of buried pipelines. The damage indexes are obtained by combining a damage probability matrix (DPM) with the annual probability of occurrence of

El-Sayed A. Mashaly; Tushar K. Datta

1989-01-01

212

Output structure for buried-channel CCD  

Microsoft Academic Search

An output structure for buried-channel charge coupled devices (CCD) is presented which permits output voltage swings of several volts without restricting the design of the buried-channel or requiring excessive drain voltage. Its application to experimental CCD imaging devices is discussed.

E. S. Schlig; S. G. Chamberlain

1984-01-01

213

Output structure for buried-channel CCD  

NASA Astrophysics Data System (ADS)

An output structure for buried-channel charge coupled devices (CCD) is presented which permits output voltage swings of several volts without restricting the design of the buried-channel or requiring excessive drain voltage. Its application to experimental CCD imaging devices is discussed.

Schlig, E. S.; Chamberlain, S. G.

1984-12-01

214

Theory Underlying the Peripheral Vision Horizon Device.  

National Technical Information Service (NTIS)

A simple statement of the Peripheral Vision Horizon Device (PVHD) theory is that the likelihood of pilot disorientation in flight can be much reduced by providing a new kind of artificial horizon that will provide orientation information to peripheral vis...

K. E. Money

1982-01-01

215

A full coupled numerical analysis approach for buried structures subjected to subsurface blast  

Microsoft Academic Search

The physical processes during an explosion in soil and the subsequent response of buried structures are extremely complex. Combining all these processes into a single analysis model involves several numerical difficulties but such a model will enable more realistic reproduction of the underlying physical processes. This paper presents a full coupled numerical analysis approach, in which the SPH (smooth particle

Zhongqi Wang; Yong Lu; Hong Hao; Karen Chong

2005-01-01

216

Spin and its relation to the Horizon  

Microsoft Academic Search

The author had previously suggested the the CMBR was not necessarily the result of just the big-bang, but may in fact be the Horizon of the Universe. This conclusion was reached by noting the fact that Horizons of curved surfaces, unlike flat surfaces are non-magnifiable. If one looks at the Horizon of the earth, say on a beach by the

Richard Kriske

2010-01-01

217

Receding horizon control of nonlinear systems  

Microsoft Academic Search

The receding horizon control strategy provides a relatively simple method for determining feedback control for linear or nonlinear systems; the method is especially useful for the control of slow nonlinear systems, such as chemical batch processes, where it is possible to solve, sequentially, open-loop, fixed-horizon, optimal control problems online. The authors show that receding horizon control stabilizes a wide class

H. Michalska; D. Q. Mayne

1989-01-01

218

Distribution of Active Ectomycorrhizal Short Roots in Forest Soils of the Inland Northwest: Effects of Site and Disturbance.  

National Technical Information Service (NTIS)

Approximately 75 percent of ectomycorrhizal activities that occurred in soils from eight undisturbed and six variously disturbed sites occurred in shallow organic horizons. These horizons represented only the first 4 cm of soil depth. This disproportionat...

A. E. Harvey M. F. Jurgensen M. J. Larsen J. A. Schlieter

1986-01-01

219

In-situ vitrification of soil  

DOEpatents

A method of vitrifying soil at or below a soil surface location. Two or more conductive electrodes are inserted into the soil for heating of the soil mass between them to a temperature above its melting temperature. Materials in the soil, such as buried waste, can thereby be effectively immobilized.

Brouns, Richard A. (Kennewick, WA); Buelt, James L. (Richland, WA); Bonner, William F. (Richland, WA)

1983-01-01

220

Modelling the buried human body environment in upland climes using three contrasting field sites.  

PubMed

Despite an increasing literature on the decomposition of human remains, whether buried or exposed, it is important to recognise the role of specific microenvironments which can either trigger or delay the rate of decomposition. Recent casework in Northern England involving buried and partially buried human remains has demonstrated a need for a more detailed understanding of the effect of contrasting site conditions on cadaver decomposition and on the microenvironment created within the grave itself. Pigs (Sus scrofa) were used as body analogues in three inter-related taphonomy experiments to examine differential decomposition of buried human remains. They were buried at three contrasting field sites (pasture, moorland, and deciduous woodland) within a 15 km radius of the University of Bradford, West Yorkshire, UK. Changes to the buried body and the effect of these changes on hair and associated death-scene textile materials were monitored as was the microenvironment of the grave. At recovery, 6, 12 and 24 months post-burial, the extent of soft tissue decomposition was recorded and samples of fat and soil were collected for gas chromatography mass spectrometry (GCMS) analysis. The results of these studies demonstrated that (1) soil conditions at these three burial sites has a marked effect on the condition of the buried body but even within a single site variation can occur; (2) the process of soft tissue decomposition modifies the localised burial microenvironment in terms of microbiological load, pH, moisture and changes in redox status. These observations have widespread application for the investigation of clandestine burial and time since deposition, and in understanding changes within the burial microenvironment that may impact on biomaterials such as hair and other associated death scene materials. PMID:16973322

Wilson, Andrew S; Janaway, Robert C; Holland, Andrew D; Dodson, Hilary I; Baran, Eve; Pollard, A Mark; Tobin, Desmond J

2006-09-14

221

Describing Soils: Calibration Tool for Teaching Soil Rupture Resistance  

ERIC Educational Resources Information Center

|Rupture resistance is a measure of the strength of a soil to withstand an applied stress or resist deformation. In soil survey, during routine soil descriptions, rupture resistance is described for each horizon or layer in the soil profile. The lower portion of the rupture resistance classes are assigned based on rupture between thumb and…

Seybold, C. A.; Harms, D. S.; Grossman, R. B.

2009-01-01

222

New Horizons Launch Contingency Effort  

Microsoft Academic Search

On 19 January 2006 at 2:00 PM EST, the NASA New Horizons spacecraft (SC) was launched from the Cape Canaveral Air Force Station (CCAFS), FL, onboard an Atlas V 551\\/Centaur\\/STAR™ 48B launch vehicle (LV) on a mission to explore the Pluto Charon planetary system and possibly other Kuiper Belt Objects. It carried a single Radioisotope Thermoelectric Generator (RTG). As part

Yale Chang; Matthew H. Lear; Brian E. McGrath; Gene A. Heyler; Naruhisa Takashima; W. Donald Owings

2007-01-01

223

1986 WIPP horizon permeability measurements  

SciTech Connect

A series of permeability measurements in the WIPP facility have been planned for fiscal year 1986. These measurements are to be made by S-Cubed and SNL and follow from and supplement previous measurements. These measurements are part of the overall WIPP horizon permeability testing and are justified and described in general terms in the previously published test plan; this paper discusses the technical motivation and test design concepts of these particular measurements.

Stormont, J.

1985-12-16

224

Penrose inequality and apparent horizons  

SciTech Connect

A spherically symmetric spacetime is presented with an initial data set that is asymptotically flat, satisfies the dominant energy condition, and such that on this initial data M<{radical}(A/16{pi}), where M is the total mass and A is the area of the apparent horizon. This provides a counterexample to a commonly stated version of the Penrose inequality, though it does not contradict the true Penrose inequality.

Ben-Dov, Ishai [Enrico Fermi Institute and Department of Physics, University of Chicago, 5640 S. Ellis Avenue, Chicago, Illinois 60637-1433 (United States)

2004-12-15

225

The effects of feeding by Oniscus asellus (Isopoda) on nutrient cycling in an incubated hardwood forest soil  

Microsoft Academic Search

Oniscus asellus produced changes in the nutrients leached from Oie and Oa horizons of a hardwood forest soil. Soil with isopods lost more K+ (54%) from the Oie horizon and more Ca2+ (25%), Mg2+ (40%), and water-extractable S (23%) from the Oa horizon than soil without isopods. In contrast, soils with isopods lost less Ca2+ (39076) from the Oie horizon

C. R. Morgan; S. C. Schindler; M. J. Mitchell

1989-01-01

226

Horizons cannot save the landscape  

NASA Astrophysics Data System (ADS)

Solutions with anti-D3 branes in a Klebanov-Strassler geometry with positive charge dissolved in fluxes have a certain singularity corresponding to a diverging energy density of the Ramond-Ramond and Neveu-Schwarz-Neveu-Schwarz three-form fluxes. There are many hopes and arguments for and against this singularity, and we attempt to settle the issue by examining whether this singularity can be cloaked by a regular event horizon. This is equivalent to the existence of asymptotically Klebanov-Tseytlin or Klebanov-Strassler black holes whose charge measured at the horizon has the opposite sign to the asymptotic charge. We find that no such Klebanov-Tseytlin solution exists. Furthermore, for a large class of Klebanov-Strassler black holes we considered, the charge at the horizon must also have the same sign as the asymptotic charge and is completely determined by the temperature, the number of fractional branes and the gaugino masses of the dual gauge theory. Our result suggests that antibrane singularities in backgrounds with charge in the fluxes are unphysical, which in turn raises the question as to whether antibranes can be used to uplift anti-de Sitter vacua to deSitter ones. Our results also point to a possible instability mechanism for the antibranes.

Bena, Iosif; Buchel, Alex; Dias, Óscar J. C.

2013-03-01

227

The role of soil-forming processes in the definition of taxa in Soil Taxonomy and the World Soil Reference Base  

Microsoft Academic Search

Modern soil taxonomic systems, including Soil Taxonomy (ST) and the World Reference Base (WRB) for Soil Resources, classify soils using diagnostic horizons, properties, and materials. Although these systems are based on genetic principles, the approaches used have de-emphasized the role of soil processes in soil taxonomic systems. Meanwhile, a consideration of soil processes is important for understanding the genetic underpinnings

J. G. Bockheim; A. N. Gennadiyev

2000-01-01

228

Corrosion rates of buried pipelines caused by geomagnetic storms  

SciTech Connect

Telluric effects associated with geomagnetic field variations caused currents to flow in buried pipelines, which present a continuing problem for monitoring cathodic protection. Protection methods involving the application of a noncorrosive coating with cathodic protection should present the circulation of erratic currents. Nevertheless, often these currents cannot be compensated. During days of high geomagnetic activity, an excess of current that cannot be drained circulates along the pipe. This effect has a strong dependence on the electrical resistivity of the host soil, produces a strong current channeling along the pipes, and increases the risk of corrosion. A method was proposed to quantify the corrosion effects over the pipelines, assuming the geomagnetic field as the external source responsible for the erratic currents. Nondisturbed fields and geomagnetic storms were modeled and pipeline currents were calculated as a function of the characteristics of the soils and pipe sizes using a numerical code previously developed.

Osella, A.; Favetto, A.; Lopez, E.

1999-07-01

229

Synthetic aperture radar performance in detecting shallow buried targets  

NASA Astrophysics Data System (ADS)

A radar performance model is developed to analyze the capability of wide-band, high- resolution airborne synthetic aperture radar detection of shallow buried targets such as metallic M-20 mines and utility cables. Feasible target detection depths are estimated as functions of radar polarization, depression angle, and frequency in UHF and VHF bands. The performance model has incorporated wave propagation loss, due to wave attenuation inside the soil medium, wave reflection, and divergence at the air-ground interface, radar target cross section estimation via method of moments, radar interference, including both ambient man-made noise and empirical backscattered ground surface clutter, which is determined from existing clutter measurements for bare soil, rocks, and desert terrain.

Jao, Jen King; Lee, Check F.; Merchant, Barbara L.

1996-05-01

230

Latex-modified grouts for in-situ stabilization of buried transuranic/mixed waste  

SciTech Connect

The Department of Applied Science at Brookhaven national Laboratory was requested to investigate latex-modified grouts for in-situ stabilization of buried TRU/mixed waste for INEL. The waste exists in shallow trenches that were backfilled with soil. The objective was to formulate latex-modified grouts for use with the jet grouting technique to enable in-situ stabilization of buried waste. The stabilized waste was either to be left in place or retrieved for further processing. Grouting prior to retrieval reduces the potential release of contaminants. Rheological properties of latex-modified grouts were investigated and compared with those of conventional neat cement grouts used for jet grouting.

Allan, M.L.

1996-06-01

231

Periglacial morphogenesis in the Paris basin: insight from geophysical survey and consequences for the fate of soil pollution  

NASA Astrophysics Data System (ADS)

Geophysical survey by Automatic Resistivity Profiling (ARP©) system of the Pierrelaye-Bessancourt area revealed remarkable conductive polygon patterns of 20- to 30-m diameter detected between 0.5- and 1.7-m depth. Trenches dug down to the limestone substrate allowed detailing of the pedological and lithological units that compose such polygonal features. The patterns are formed by greenish glauconite and carbonated sand hollows where clay-rich pedological horizons bend downward, forming narrow tongs extending up to 2- to 3-m depth. Such structures were interpreted as a buried polygonal ice-wedge network (thermokarst depressions). Geometrical relationships between the lithological units and consecutive erosional surfaces allowed the identification of successive landscape events and a landscape chronology. The sequence started during the Saalian glaciation with (1) the development of patterned grounds by thermokarstic cryoturbation; (2) the consecutive deflation/erosion during post-permafrost aridity; (3) the loess and eolian sand deposits; (4) the weathering of the former deposits with development of pedogenic horizons during the Eemian interglacial; (5) the recurrent cryoturbation and thermal cracking leading to infolding of the pedogenic horizons during the Pleniglacial optimum (Weichselian); and finally (5) the erosion that levelled the periglacial microreliefs, most probably during the last glacial stage (Weichselian), leading to the modern landscape. In this agricultural area, urban waste water has been spread for more than 100 years by flooding irrigation for food crop production and has led to high levels of metal pollution in the surface horizons of the soils. The polygonal cryogenic structures have major impacts on soil hydrology and dispersion/distribution of heavy metals toward the geological substrate. Such structures are essential to consider when conceiving proposals for future soil management of this polluted area.

Thiry, Médard; van Oort, Folkert; Thiesson, Julien; Van Vliet-Lanoe, Brigitte

2013-09-01

232

7 CFR 1755.505 - Buried services.  

Code of Federal Regulations, 2013 CFR

...accepted or RUS technically accepted. The conductor size for two and three pair buried...wire including neutral and grounding conductors: Open 4 [102] In conduit ...television antennas, Lead-in and grounding conductors 4 [102] Lightning rods and...

2013-01-01

233

TNX Burying Ground: Environmental information document  

SciTech Connect

The TNX Burying Ground, located within the TNX Area of the Savannah River Plant (SRP), was originally built to dispose of debris from an experimental evaporator explosion at TNX in 1953. This evaporator contained approximately 590 kg of uranyl nitrate. From 1980 to 1984, much of the waste material buried at TNX was excavated and sent to the SRP Radioactive Waste Burial Grounds for reburial. An estimated 27 kg of uranyl nitrate remains buried at TNX. The TNX Burying Ground consists of three sites known to contain waste and one site suspected of containing waste material. All four sites are located within the TNX security fenceline. Groundwater at the TNX Burying Ground was not evaluated because there are no groundwater monitoring wells installed in the immediate vicinity of this waste site. The closure options considered for the TNX Burying Ground are waste removal and closure, no waste removal and closure, and no action. The predominant pathways for human exposure to chemical and/or radioactive constituents are through surface, subsurface, and atmospheric transport. Modeling calculations were made to determine the risks to human population via these general pathways for the three postulated closure options. An ecological assessment was conducted to predict the environmental impacts on aquatic and terrestrial biota. The relative costs for each of the closure options were estimated.

Dunaway, J.K.W.; Johnson, W.F.; Kingley, L.E.; Simmons, R.V.; Bledsoe, H.W.

1987-03-01

234

Spacetime near isolated and dynamical trapping horizons  

NASA Astrophysics Data System (ADS)

We study the near-horizon spacetime for isolated and dynamical trapping horizons (equivalently marginally outer trapped tubes). The metric is expanded relative to an ingoing Gaussian null coordinate and the terms of that expansion are explicitly calculated to second order. For the spacelike case, knowledge of the intrinsic and extrinsic geometry of the (dynamical) horizon is sufficient to determine the near-horizon spacetime, while for the null case (an isolated horizon) more information is needed. In both cases spacetime is allowed to be of arbitrary dimension and the formalism accommodates both general relativity as well as more general field equations. The formalism is demonstrated for two applications. First, spacetime is considered near an isolated horizon and the construction is both checked against the Kerr-Newman solution and compared to the well-known near-horizon limit for stationary extremal black hole spacetimes. Second, spacetime is examined in the vicinity of a slowly evolving horizon and it is demonstrated that there is always an event horizon candidate in this region. The geometry and other properties of this null surface match those of the slowly evolving horizon to leading order and in this approximation the candidate evolves in a locally determined way. This generalizes known results for Vaidya as well as certain spacetimes known from studies of the fluid-gravity correspondence.

Booth, Ivan

2013-01-01

235

Simulation of the environmental fate and transport of chemical signatures from buried land mines  

NASA Astrophysics Data System (ADS)

The fate and transport of chemical signature molecules that emanate from buried landmines is strongly influenced by physical chemical properties and by environmental conditions of the specific chemical compounds. Published data have been evaluated as the input parameters that are used in the simulation of the fate and transport processes. A one- dimensional model developed for screening agricultural pesticides was modified and used to simulate the appearance of a surface flux above a buried landmine and estimate the subsurface total concentration. The physical chemical properties of TNT cause a majority of the mass released to the soil system to be bound to the solid phase soil particles. The majority of the transport occurs in the liquid phase with diffusion and evaporation driven advection of soil water as the primary mechanisms for the flux to the ground surface. The simulations provided herein should only be used for initial conceptual designs of chemical pre-concentration subsystems or complete detection systems. The physical processes modeled required necessary simplifying assumptions to allow for analytical solutions. Emerging numerical simulation tools will soon be available that should provide more realistic estimates that can be used to predict the success of landmine chemical detection surveys based on knowledge of the chemical and soil properties, and environmental conditions where the mines are buried. Additional measurements of the chemical properties in soils are also needed before a fully predictive approach can be confidently applied.

Phelan, James M.; Webb, Stephen W.

1998-09-01

236

Simulation of the environmental fate and transport of chemical signatures from buried landmines  

SciTech Connect

The fate and transport of chemical signature molecules that emanate from buried landmines is strongly influenced by physical chemical properties and by environmental conditions of the specific chemical compounds. Published data have been evaluated as the input parameters that are used in the simulation of the fate and transport processes. A one-dimensional model developed for screening agricultural pesticides was modified and used to simulate the appearance of a surface flux above a buried landmine and estimate the subsurface total concentration. The physical chemical properties of TNT cause a majority of the mass released to the soil system to be bound to the solid phase soil particles. The majority of the transport occurs in the liquid phase with diffusion and evaporation driven advection of soil water as the primary mechanisms for the flux to the ground surface. The simulations provided herein should only be used for initial conceptual designs of chemical pre-concentration subsystems or complete detection systems. The physical processes modeled required necessary simplifying assumptions to allow for analytical solutions. Emerging numerical simulation tools will soon be available that should provide more realistic estimates that can be used to predict the success of landmine chemical detection surveys based on knowledge of the chemical and soil properties, and environmental conditions where the mines are buried. Additional measurements of the chemical properties in soils are also needed before a fully predictive approach can be confidently applied.

Phelan, J.M.; Webb, S.W.

1998-03-01

237

Topological deformation of isolated horizons  

SciTech Connect

We show that the Gauss-Bonnet term can have physical effects in four dimensions. Specifically, the entropy of a black hole acquires a correction term that is proportional to the Euler characteristic of the cross sections of the horizon. While this term is constant for a single black hole, it will be a nontrivial function for a system with dynamical topologies such as black-hole mergers: it is shown that for certain values of the Gauss-Bonnet parameter, the second law of black-hole mechanics can be violated.

Liko, Tomas [Department of Physics and Physical Oceanography, Memorial University of Newfoundland, St. John's, Newfoundland, A1B 3X7 (Canada)

2008-03-15

238

Secondary metabolites released by the burying beetle Nicrophorus vespilloides: chemical analyses and possible ecological functions.  

PubMed

Burying beetles of the genus Nicrophorus localize small vertebrate carcasses by emitted volatiles. The carcass that serves as reproduction and breeding site is buried in the soil by the beetles. Biparental care for offspring includes both preservation of the carrion and its preparation as diet and nursery. Buried carcasses show no signs of microbial decay, and those experimentally treated with Nicrophorus secretions are known to grow fewer bacteria and fungi. In order to investigate the chemical composition of these secretions, we used GC-MS for analysis of methanolic extracts of anal and oral secretions released by adult N. vespilloides. Furthermore, we analyzed the headspace of adult N. vespilloides by SPME-GC-MS and searched for compounds with known antimicrobial activity. We identified 34 compounds in the headspace, and anal and oral secretions, 26 of which occurred consistently. We discuss the ecological relevance of these compounds with respect to both their antimicrobial activity and ecological relevance. PMID:21667150

Degenkolb, Thomas; Düring, Rolf-Alexander; Vilcinskas, Andreas

2011-06-11

239

Horizon dynamics of distorted rotating black holes  

SciTech Connect

We present numerical simulations of a rotating black hole distorted by a pulse of ingoing gravitational radiation. For strong pulses, we find up to five concentric marginally outer trapped surfaces. These trapped surfaces appear and disappear in pairs, so that the total number of such surfaces at any given time is odd. The world tubes traced out by the marginally outer trapped surfaces are found to be spacelike during the highly dynamical regime, approaching a null hypersurface at early and late times. We analyze the structure of these marginally trapped tubes in the context of the dynamical horizon formalism, computing the expansion of outgoing and incoming null geodesics, as well as evaluating the dynamical horizon flux law and the angular momentum flux law. Finally, we compute the event horizon. The event horizon is well-behaved and approaches the apparent horizon before and after the highly dynamical regime. No new generators enter the event horizon during the simulation.

Chu, Tony; Cohen, Michael I. [Theoretical Astrophysics 350-17, California Institute of Technology, Pasadena, California 91125 (United States); Pfeiffer, Harald P. [Canadian Institute for Theoretical Astrophysics, 60 St. George Street, University of Toronto, Toronto, ON M5S 3H8 (Canada)

2011-05-15

240

Extremality conditions for isolated and dynamical horizons  

SciTech Connect

A maximally rotating Kerr black hole is said to be extremal. In this paper we introduce the corresponding restrictions for isolated and dynamical horizons. These reduce to the standard notions for Kerr but in general do not require the horizon to be either stationary or rotationally symmetric. We consider physical implications and applications of these results. In particular we introduce a parameter e which characterizes how close a horizon is to extremality and should be calculable in numerical simulations.

Booth, Ivan; Fairhurst, Stephen [Department of Mathematics and Statistics, Memorial University of Newfoundland St. John's, Newfoundland and Labrador, A1C 5S7 (Canada); Department of Physics, University of Wisconsin-Milwaukee Milwaukee, Wisconsin, 53201 (United States); LIGO-California Institute of Technology, Pasadena, California 91125 (United States); School of Physics and Astronomy, Cardiff University, Cardiff, CF2 3YB (United Kingdom)

2008-04-15

241

Area products for stationary black hole horizons  

NASA Astrophysics Data System (ADS)

Area products for multihorizon stationary black holes often have intriguing properties, and are often (though not always) independent of the mass of the black hole itself (depending only on various charges, angular momenta, and moduli). Such products are often formulated in terms of the areas of inner (Cauchy) horizons and outer (event) horizons, and sometimes include the effects of unphysical “virtual” horizons. But the conjectured mass independence sometimes fails. Specifically, for the Schwarzschild–de Sitter [Kottler] black hole in (3+1) dimensions it is shown by explicit exact calculation that the product of event horizon area and cosmological horizon area is not mass independent. (Including the effect of the third “virtual” horizon does not improve the situation.) Similarly, in the Reissner-Nordstrom–anti-de Sitter black hole in (3+1) dimensions the product of the inner (Cauchy) horizon area and event horizon area is calculated (perturbatively), and is shown to be not mass independent. That is, the mass independence of the product of physical horizon areas is not generic. In spherical symmetry, whenever the quasilocal mass m(r) is a Laurent polynomial in aerial radius, r=A/4?, there are significantly more complicated mass-independent quantities, the elementary symmetric polynomials built up from the complete set of horizon radii (physical and virtual). Sometimes it is possible to eliminate the unphysical virtual horizons, constructing combinations of physical horizon areas that are mass independent, but they tend to be considerably more complicated than the simple products and related constructions currently being mooted in the literature.

Visser, Matt

2013-08-01

242

Field-scale permeation testing of jet-grouted buried waste sites  

SciTech Connect

The Idaho National Engineering Laboratory (INEL) conducted field-scale hydraulic conductivity testing of simulated buried waste sites with improved confinement. The improved confinement was achieved by jet grouting the buried waste, thus creating solid monoliths. The hydraulic conductivity of the monoliths was determined using both the packer technique and the falling head method. The testing was performed on simulated buried waste sites utilizing a variety of encapsulating grouts, including high-sulfate-resistant Portland cement, TECT, (a proprietary iron oxide cement) and molten paraffin. By creating monoliths using in-situ jet grouting of encapsulating materials, the waste is simultaneously protected from subsidence and contained against further migration of contaminants. At the INEL alone there is 56,000 m{sup 3} of buried transuranic waste commingled with 170,000--224,000 m{sup 3} of soil in shallow land burial. One of the options for this buried waste is to improve the confinement and leave it in place for final disposal. Knowledge of the hydraulic conductivity for these monoliths is important for decision-makers. The packer tests involved coring the monolith, sealing off positions within the core with inflatable packers, applying pressurized water to the matrix behind the seal, and observing the water flow rate. The falling head tests were performed in full-scale 3-m-diameter, 3-m-high field-scale permeameters. In these permeameters, both water inflow and outflow were measured and equated to a hydraulic conductivity.

Loomis, G.G. [Lockheed Idaho Technologies Co., Idaho Falls, ID (United States); Zdinak, A.P. [MSE Technology Applications Inc., Butte, MT (United States)

1996-12-31

243

Spatial arrangement of soil mantle in Glacis de Buenavista, Mexico as a product and record of landscape evolution  

NASA Astrophysics Data System (ADS)

Factors controlling spatial soil organization have recently attracted the attention of soil scientists because they can contribute to regional management of soil resources. We present here a case study in the Glacis de Buenavista (Mexico), an extended volcanic piedmont, in order to develop an integral understanding of its soil cover as a product and, at the same time, as a record of the main stages of landscape evolution. Three phenomena were considered: Luvisol and Vertisol type soils, and pedosediments, all of them analyzed in terms of their development degree (clay content, macro and micromorphology, selective extractions of Fe (Fed, Feo), silicon (Sio) and aluminum (Alo), weathering index and clay mineralogy). Luvisols, represented in the Ahuatenco, Mexicapa and Buenavista sections, are located in the northern and central part of the area. They are red-clayey, polygenetic soils that show strong weathering (with high kaolinitic clay content and high weathering index values), clay illuviation, and reductomorphic processes, combined with vertic features in some parts of the profiles. Vertisols dominate the central and southern portion of the Glacis. They exhibit cracking, angular blocks with wedge-like shapes, slickensides and stress-cutans. The pedogenesis of the Vertisol type is clearly associated with the presence of smectitic minerals in the clay fraction as a product of neoformation. Factors controlling this pedodiversity are: relief, which affects bioclimatic differentiation within the studied landsurface and defines the lateral redistribution of moisture and dissolved substances; and time. Luvisols represent a longer pedogenetic phase that started in the Late Pleistocene, according to the age of buried paleosols, while Vertisols mainly originated in the Late Holocene (according to the age of buried organic horizons). Pedosediments are located in the central area of the Glacis. Here, past and present geomorphic processes interact to produce the greatest soil diversity. The recent human-induced erosion partly destroyed polycyclic Luvisols and exposed ancient subsurface pedosedimentary strata. At the same time it produced patches of unconsolidated pedosediments consisting mostly of redeposited Luvisol materials.

Díaz-Ortega, J.; Solleiro-Rebolledo, E.; Sedov, S.

2011-12-01

244

Buried object detection with parametric sonar  

NASA Astrophysics Data System (ADS)

Detection of buried objects with parametric sonar is studied using time-frequency methods. The sonar equation is used as a framework to assess the sonar system characteristics, the sediment response, and the buried object response. Field tests were conducted to measure the source levels of difference frequencies in the nearfield and spectral components at different ranges. The results of these tests were compared with the predicted values from the Moffett-Mellen model in the nearfield. The analysis reveals the nonstationary and nonlinear behavior of the sonar system and environment and shows that a linear systems approach is not realistic. Analysis of sediment variability and attenuation quantifies the nonstationarity of the media and motivates the use of gain correction techniques presented in this dissertation. The response of buried objects was found to exhibit resonances and time- frequency dependence. Acoustic resonance theory is used to explain the target response and is shown to be effective in estimating target size. The use of time- frequency techniques for object detection in such a system is discussed and it is shown that the Wigner-Ville distribution and the wavelet transform are particularly well suited to the interpretation of the data and detection of buried objects. Results are given for several buried objects and gas bubbles in sediment.

Kalcic, Maria Theresa

2000-10-01

245

78 FR 54298 - Horizons ETFs Management (USA) LLC and Horizons ETF Trust; Notice of Application  

Federal Register 2010, 2011, 2012, 2013

...Horizons ETFs Management (USA) LLC (``Horizons...17, 2013 and amended on August 27, 2013. Hearing or...Horizons ETFs Management (USA) LLC, One Bryant Park...TBA Transactions,\\11\\ short positions and other...its primary market. \\11\\ A TBA Transaction...

2013-09-03

246

Identification of immunity-related genes in the burying beetle Nicrophorus vespilloides by suppression subtractive hybridization.  

PubMed

Burying beetles reproduce on small vertebrate cadavers which they bury in the soil after localization through volatiles emitted from the carcass. They then chemically preserve the carcass and prepare it as a diet for the adults and their offspring. It is predicted that exposure to high loads of soil and/or carrion-associated microbes necessitates an effective immune system. In the present paper, we report experimental screening for immunity-related genes in the burying beetle Nicrophorus vespilloides using the suppression subtractive hybridization approach. A total of 1179 putative gene objects were identified in the Nicrophorus cDNA library, which was enriched for transcripts differentially expressed upon challenge with heat-inactivated bacteria. In addition to genes known to be involved in immunity-related recognition and signalling, we found transcripts encoding for antimicrobial peptides and for an array of enzymes that can be linked to immunity or to stress-induced pathways. We also determined proteins that may contribute to detoxification of toxins produced by microbial competitors. In addition, factors involved in mRNA stability determination and central components of the RNA interference machinery were identified, implying transcriptional reprogramming and potential stress-induced retrotransposon elimination. The identified candidate immune effector and stress-related genes may provide important information about the unusual ecology and evolution of the burying beetles. PMID:21929718

Vogel, H; Badapanda, C; Vilcinskas, A

2011-09-19

247

Tests of a system to exclude roots from buried radioactive waste in a warm, humid climate  

SciTech Connect

Vegetation is commonly used to stabilize the ground covering buried waste sites. However, constituents of buried waste can be brought to the surface if the waste is penetrated by plant roots. An ideal waste burial system would allow the use of vegetation to stabilize the soil above the buried waste but would exclude roots from the waste. One system that shows considerable promise is a slow release encapsulation of a root growth inhibitor (Trifluralin). Projected lifetimes of the capsule are in the order of 100 years. The capsule is bonded to a geotextile, which provides an easy means of distributing the capsule evenly over the area to be protected. Vegetation grown in the soil above the barrier has provided good ground cover, although some decrease in growth has been found in some species. Of the species tested the sensitivity to the biobarrier, as measured by the distance root growth stops near the barrier, is bamboo> bahia grass> bermuda grass> soybean. Potential uses for the biobarrier at the Savannah River Site (SRS) include the protection of clay caps over buried, low-level saltstone and protection of gravel drains and clay caps over decommissioned seepage basins. Trails of the biobarrier as part of waste site caps are scheduled to begin during the next 12 months.

Murphy, C.E. Jr.; Corey, J.C. [Westinghouse Savannah River Co., Aiken, SC (United States); Adriano, D.C. [Savannah River Ecology Lab., Aiken, SC (United States); Decker, O.D.; Griggs, R.D. [Lilly Research Laboratories, Greenfield, IN (United States)

1989-12-31

248

Tests of a system to exclude roots from buried radioactive waste in a warm, humid climate  

SciTech Connect

Vegetation is commonly used to stabilize the ground covering buried waste sites. However, constituents of buried waste can be brought to the surface if the waste is penetrated by plant roots. An ideal waste burial system would allow the use of vegetation to stabilize the soil above the buried waste but would exclude roots from the waste. One system that shows considerable promise is a slow release encapsulation of a root growth inhibitor (Trifluralin). Projected lifetimes of the capsule are in the order of 100 years. The capsule is bonded to a geotextile, which provides an easy means of distributing the capsule evenly over the area to be protected. Vegetation grown in the soil above the barrier has provided good ground cover, although some decrease in growth has been found in some species. Of the species tested the sensitivity to the biobarrier, as measured by the distance root growth stops near the barrier, is bamboo> bahia grass> bermuda grass> soybean. Potential uses for the biobarrier at the Savannah River Site (SRS) include the protection of clay caps over buried, low-level saltstone and protection of gravel drains and clay caps over decommissioned seepage basins. Trails of the biobarrier as part of waste site caps are scheduled to begin during the next 12 months.

Murphy, C.E. Jr.; Corey, J.C. (Westinghouse Savannah River Co., Aiken, SC (United States)); Adriano, D.C. (Savannah River Ecology Lab., Aiken, SC (United States)); Decker, O.D.; Griggs, R.D. (Lilly Research Laboratories, Greenfield, IN (United States))

1989-01-01

249

Understanding the toxicity of buried radioactive waste and its impacts.  

PubMed

The oral ingestion toxicities of buried high level radioactive waste from nuclear power plants and of the natural radioactivity in the ground are calculated and expressed as cancer doses, the number of fatal cancers predicted by the linear no-threshold theory if all of the material were fed to people. Unless the size of the U.S. nuclear power industry is greatly expanded, there will probably never be more than 2 trillion cancer doses (CD) in U.S. repositories, as compared with 31 trillion CD in the ground above them. Measurements of the uranium, thorium, and radium in human bodies indicate that the latter cause 500 deaths per year in U.S. The great majority of this material is derived from the top few meters of soil that are penetrated by plant roots. It is concluded that the annual number of U.S. deaths from buried nuclear wastes will be about 1.0 (or less), orders of magnitude less than the number from coal burning electricity generation, the principal competitor of nuclear power. PMID:16155457

Cohen, Bernard L

2005-10-01

250

Sensor System Fo4r Buried Waste Containment Sites  

DOEpatents

A sensor system for a buried waste containment site having a bottom wall barrier and sidewall barriers, for containing hazardous waste. The sensor system includes one or more sensor devices disposed in one or more of the barriers for detecting a physical parameter either of the barrier itself or of the physical condition of the surrounding soils and buried waste, and for producing a signal representing the physical parameter detected. Also included is a signal processor for receiving signals produced by the sensor device and for developing information identifying the physical parameter detected, either for sounding an alarm, displaying a graphic representation of a physical parameter detected on a viewing screen and/or a hard copy printout. The sensor devices may be deployed in or adjacent the barriers at the same time the barriers are deployed and may be adapted to detect strain or cracking in the barriers, leakage of radiation through the barriers, the presence and leaking through the barriers of volatile organic compounds, or similar physical conditions.

Smith, Ann Marie (Pocatello, ID); Gardner, Bradley M. (Idaho Falls, ID); Kostelnik, Kevin M. (Idaho Falls, ID); Partin, Judy K. (Idaho Falls, ID); Lancaster, Gregory D. (Idaho Falls, ID); Pfeifer, Mary Catherine (San Antonio, NM)

2003-11-18

251

Sensor System Fo4r Buried Waste Containment Sites  

DOEpatents

A sensor system for a buried waste containment site having a bottom wall barrier and/or sidewall barriers, for containing hazardous waste. The sensor system includes one or more sensor devices disposed in one or more of the barriers for detecting a physical parameter either of the barrier itself or of the physical condition of the surrounding soils and buried waste, and for producing a signal representing the physical parameter detected. Also included is a signal processor for receiving signals produced by the sensor device and for developing information identifying the physical parameter detected, either for sounding an alarm, displaying a graphic representation of a physical parameter detected on a viewing screen and/or a hard copy printout. The sensor devices may be deployed in or adjacent the barriers at the same time the barriers are deployed and may be adapted to detect strain or cracking in the barriers, leakage of radiation through the barriers, the presence and leaking through the barriers of volatile organic compounds, or similar physical conditions.

Smith, Ann Marie (Pocatello, ID); Gardner, Bradley M. (Idaho Falls, ID); Kostelnik, Kevin M. (Idaho Falls, ID); Partin, Judy K. (Idaho Falls, ID); Lancaster, Gregory D. (Idaho Falls, ID); Pfeifer, Mary Catherine (San Antonio, NM)

2005-09-27

252

Radar detection of simulant mines buried in frozen ground  

NASA Astrophysics Data System (ADS)

We are investigating the environmental effects on radar detection of simulant mines (SIMs). SIMs are standard test targets developed by the US Army Project Manager-Mines, Countermine and Demolitions, and VSE Corporation for testing and evaluation of mine detection equipment. These test targets are filed with RTV silicone rubber, which has similar dielectric properties as TNT and Composition B. Therefore, they interact with radar sensors in a way representative of live mines. We are using broadband frequency modulated continuous wave (FMCW) and impulse radars to obtain signatures of SIMs buried under controlled laboratory conditions and at a test site instrumented with sensors to monitor the state of the ground. We find that anti-tank SIMs buried in frozen soil, in our case a common, silty sand are easy to detect. The dominant resonances included within SIMs by a broadbeam, 1.5 GHz impulse radar are of-nadir responses that appear unique and not predictable by simple ray theories of diffraction. A narrow beam, 2-6 GHz bandwidth FMCW radar induced reflections from the top and bottom of SIMs that were clearly resolved due to the broad bandwidth of the FMCW radar.

Koh, Gary; Arcone, Steven A.

1999-08-01

253

Preservation of daily tidal cycles and stacked alluvial swamp deposits: Depositional response to early compaction of buried peat bodies  

SciTech Connect

The character of the clastic depositional environments represented in the lower Mary Lee coal zone of the Pennsylvanian Pottsville Formation in the Warrior basin Alabama (tidally influenced mud flats and alluvial swamps) was controlled by the compaction of buried peat bodies. The lowest mineable coal in the Mary Lee coal zone, the Jagger, is overlain by laminated shale and sandstone exhibiting pronounced cycle bedding. This bedding records daily tidal cyclicity in the form of sand-mud couplets. These correspond to flood-current deposition of the coarser fraction followed by fallout of the finer grained fraction during ensuing slack-water periods. These couplets are cyclically bundled-sandier bundles corresponding to spring tides and muddier bundles to neap tides (lamination counts suggest a 24-30-day cycle). The clastic sequence above the overlying Blue Creek coal is characterized by a series of stacked alluvial swamp horizons. These can be identified by autochthonous fossil plants and pedological features indicative of gleyed paleosols. Catastrophic flooding buried and preserved these horizons. The rapid, early compaction of the buried Jagger and Blue Creek peat bodies created accommodation space that allowed both the preservation of tidalites in the Jagger coal to Blue Creek coal interval and the stacking of alluvial swamp paleosols above the Blue Creek seam. Carboniferous peats were comprised of highly compressible plant parts and hence, were sensitive to sediment loading. Once the peat bodies had compressed to a certain extent, stability of the overlying sediment surface created conditions amenable to resumption of peat accumulation.

Demko, T.M.; Gastaldo, R.A. (Auburn Univ., AL (USA))

1990-05-01

254

Relationships Between Soil Moisture-Holding Properties and Soil Texture, Organic Matter Content, and Bulk Density.  

National Technical Information Service (NTIS)

Specimens from the surface horizon and the subsoil of 62 soil horizons in Hedmark and Oppland were investigated to study how the mechanical composition of the soil, the organic matter content and the bulk density affect their porosity and air capacity and...

H. C. F. Riley

1981-01-01

255

Development of three-dimensional maps of eroded soil with data from a profile cone penetrometer  

Microsoft Academic Search

Erosion of the productive surface soil from a landscape reduces crop production and alters chemical and physical properties of the soil, especially the thickness of the effective rooting depth and surface horizon thickness. Fast and reliable tools are needed to detect and map the thickness of soil horizons of eroded landscapes to allow for proper management of eroded soil for

256

Ballistic electron spectroscopy of individual buried molecules  

NASA Astrophysics Data System (ADS)

A theoretical study is presented of the ballistic electron emission spectra (BEES) of individual insulating and conducting organic molecules chemisorbed on a silicon substrate and buried under a thin gold film. It is predicted that ballistic electrons injected into the gold film from a scanning tunneling microscope tip should be transmitted so weakly to the silicon substrate by alkane molecules of moderate length (decane, hexane) and their thiolates that individual buried molecules of this type will be difficult to detect in BEES experiments. However, resonant transmission by molecules containing unsaturated C-C bonds or aromatic rings is predicted to be strong enough for BEES spectra of individual buried molecules of these types to be measured. Calculated BEES spectra of molecules of both types are presented and the effects of some simple interstitial and substitutional gold defects that may occur in molecular films are also briefly discussed.

Kirczenow, George

2007-01-01

257

Hairy black holes, horizon mass and solitons  

Microsoft Academic Search

Properties of the horizon mass of hairy black holes are discussed with emphasis on certain subtle and initially unexpected features. A key property suggests that hairy black holes may be regarded as `bound states' of ordinary black holes (without hair) and coloured solitons. This model is then used to predict the qualitative behaviour of the horizon properties of hairy black

Abhay Ashtekar; Alejandro Corichi; Daniel Sudarsky

2001-01-01

258

Horizon UV Program (HUP) atmospheric radiance measurements  

Microsoft Academic Search

Spectrometric observations (1100 A to 1800 A) of the ultraviolet radiance of Earth's atmosphere have been obtained by the Horizon Ultraviolet Program (HUP) sensor from Space Shuttle altitude at two different points in the solar cycle. Most of the radiance measurements were made during horizon scans of the earthlimb or while the HUP field of view was directed toward nadir.

F. J. Leblanc; F. P. Delgreco; J. A. Welsh; R. E. Huffman

1993-01-01

259

Reconceptualizing Knowledge at the Mathematical Horizon  

ERIC Educational Resources Information Center

|This article extends the notion of "knowledge at the mathematical horizon" or "horizon knowledge" introduced by Ball and colleagues as a part of teachers' subject matter knowledge. Our focus is on teachers' mathematical knowledge beyond the school curriculum, that is, on mathematics learnt during undergraduate college or university studies. We…

Zazkis, Rina; Mamolo, Ami

2011-01-01

260

Cosmological event horizons, thermodynamics, and particle creation  

Microsoft Academic Search

It is shown that the close connection between event horizons and thermodynamics which has been found in the case of black holes can be extended to cosmological models with a repulsive cosmological constant. An observer in these models will have an event horizon whose area can be interpreted as the entropy or lack of information of the observer about the

G. W. Gibbons; S. W. Hawking

1977-01-01

261

Surveyor observations of lunar horizon-glow  

Microsoft Academic Search

Each of the Surveyor 7, 6, and 5 spacecraft observed a line of light along its western lunar horizon following local sunset. It has been suggested that this horizon-glow (HG) is sunlight, which is forward-scattered by dust grains (~ 10µ in diam, ~ 50 grains cm-2) present in a tenuous cloud formed temporarily (? 3 h duration) just above sharp

J. J. Rennilson; D. R. Criswell

1974-01-01

262

Silicon on insulator with active buried regions  

DOEpatents

A method for forming patterned buried components, such as collectors, sources and drains, in silicon-on-insulator (SOI) devices. The method is carried out by epitaxially growing a suitable sequence of single or multiple etch stop layers ending with a thin silicon layer on a silicon substrate, masking the silicon such that the desired pattern is exposed, introducing dopant and activating in the thin silicon layer to form doped regions. Then, bonding the silicon layer to an insulator substrate, and removing the silicon substrate. The method additionally involves forming electrical contact regions in the thin silicon layer for the buried collectors.

McCarthy, Anthony M. (Menlo Park, CA)

1998-06-02

263

Silicon on insulator with active buried regions  

DOEpatents

A method for forming patterned buried components, such as collectors, sources and drains, in silicon-on-insulator (SOI) devices. The method is carried out by epitaxially growing a suitable sequence of single or multiple etch stop layers ending with a thin silicon layer on a silicon substrate, masking the silicon such that the desired pattern is exposed, introducing dopant and activating in the thin silicon layer to form doped regions. Then, bonding the silicon layer to an insulator substrate, and removing the silicon substrate. The method additionally involves forming electrical contact regions in the thin silicon layer for the buried collectors.

McCarthy, Anthony M. (Menlo Park, CA)

1996-01-01

264

Silicon on insulator with active buried regions  

DOEpatents

A method is disclosed for forming patterned buried components, such as collectors, sources and drains, in silicon-on-insulator (SOI) devices. The method is carried out by epitaxially growing a suitable sequence of single or multiple etch stop layers ending with a thin silicon layer on a silicon substrate, masking the silicon such that the desired pattern is exposed, introducing dopant and activating in the thin silicon layer to form doped regions. Then, bonding the silicon layer to an insulator substrate, and removing the silicon substrate. The method additionally involves forming electrical contact regions in the thin silicon layer for the buried collectors. 10 figs.

McCarthy, A.M.

1998-06-02

265

Silicon on insulator with active buried regions  

DOEpatents

A method is disclosed for forming patterned buried components, such as collectors, sources and drains, in silicon-on-insulator (SOI) devices. The method is carried out by epitaxially growing a suitable sequence of single or multiple etch stop layers ending with a thin silicon layer on a silicon substrate, masking the silicon such that the desired pattern is exposed, introducing dopant and activating in the thin silicon layer to form doped regions. Then, bonding the silicon layer to an insulator substrate, and removing the silicon substrate. The method additionally involves forming electrical contact regions in the thin silicon layer for the buried collectors. 10 figs.

McCarthy, A.M.

1996-01-30

266

EFFECT OF ACID TREATMENT ON DISSOLVED ORGANIC CARBON RETENTION BY A SPODIC HORIZON  

EPA Science Inventory

Processes involving the movement of organic substances in forest soils are not well understood. This study was conducted to examine the role of acidic inputs on dissolved organic carbon (DOC) mobility, processes affecting the retention of DOV by a B horizon, and SO2-4 adsorption....

267

Acidification and Recovery of a Spodosol Bs Horizon from Acidic Deposition.  

National Technical Information Service (NTIS)

A laboratory study was conducted to examine acidification and recovery of a Spodosol Bs horizon from acidic deposition in the Bear Brook Watershed (BBW) in central Maine. A mechanical vacuum extractor was used to draw solutions through a soil column at th...

R. A. Dahlgren D. C. McAvoy C. T. Driscoll

1990-01-01

268

In situ method to determine depth distribution of buried activity.  

PubMed

A method is described to determine the depth distribution of buried activity offering an alternative to conventional soil sampling and laboratory analysis by in situ measurements with small detectors inserted into the ground. As a demonstration of the method small-scale variations in the distribution of (137)Cs in a riparian marsh in central-eastern Sweden are determined using lanthanum bromide detectors (LaBr?). The results show variations of the activity ranging between 400 and 2200 kBq/m² over an area not exceeding 350 m². The decrease of the average activity since 2003 coincides with the physical decay indicating that no net redistribution of activity into this part of the marsh has occurred during the intervening years. PMID:21295985

Kastlander, J; Bargholtz, Chr

2011-01-13

269

Apparent horizon and event horizon thermodynamics of a Vaidya black hole using Damour-Ruffini method  

NASA Astrophysics Data System (ADS)

Using Damour-Ruffini method, Hawking radiation from the apparent horizon of a Vaidya black hole is calculated. The thermodynamics can be built successfully on the apparent horizon. In the meantime, when a time-dependent perturbation is given to the apparent horizon, the first law of thermodynamics can also be constructed successfully at a new supersurface near the apparent horizon. The expressions of the characteristic position and temperature are consistent with the previous results. It is concluded that the thermodynamics should be constructed on the apparent horizon exactly while the event horizon thermodynamics is just one of the perturbations near the apparent horizon. These conclusions can be regarded as providing some new evidences for our previous viewpoint.

Liu, Xianming; Liu, Wenbiao

2011-01-01

270

Development stages of Holocene soils formed in loess and loess bearing sediments at the Roman wall (Limes) in the Wetterau (Hesse, Germany)  

NASA Astrophysics Data System (ADS)

About 2000 years ago the Romans built a wall through Europe - named Limes (lat. border) in Middle Europe and Hadrian's wall in UK - with the aim to protect the borders of their empire. In many parts the Limes was constructed by digging a trench and by accumulating the excavated soil material at one side of the trench. The upper decimetres of the wall are mainly made of calcareous sediments, because the trench was dug to a depth of C horizons which are composed of loess with high carbonate content. One prerequisite for research on pedogenesis is to obtain most precise data about the age of the parent material of soil formation. Regarding this, the Limes gives an excellent opportunity to distinguish different stages of Late Holocene soil development. The study area is part of the soilscape of the Wetterau (100 - 250 m asl) situated between Taunus and Vogelsberg in Hesse, Germany. The precipitation is around 500 mm per year. Wetterau's gentle rolling hills were originally covered with loess and periglacial slope deposits. The soilscape is characterized by (Albic) Luvisols, Haplic Phaeozems, Luvic Phaeozems as well as Calcaric Regosols on upper slopes and Anthrosols in footslope positions. Particulary Haplic Phaeozems and Luvic Phaeozems have been of a wider interest of pedogenic research, since they have been formed in the Early and Mid-Holocene and, therefore, they are relic. It is supposed that the Wetterau was a Chernozem soilscape during the Early Holocene changing to a soilscape characterised by (Luvic) Phaeozems and Luvisols during the Atlantic period. Results of archaeological research on the Roman wall in the Wetterau showed that the wall was constructed in the 2nd century AD and that it had different functions over time. In this context soil investigations revealed three different stages of Holocene soil development: (i) a youngest (recent) soil situated in the wall, (ii) a paleosol conserved below the wall and (iii) a soil developed in the area nearby the wall A section through the Roman wall in the northern part of the Wetterau reveals (i) a Luvisol with limpid to dusty yellow brown and brown clay coatings in the Bt horizon developed in the sediments of the wall during the last 1800 to 1900 years. A trampling horizon can be inferred from platy microplates and horizontally oriented organ residues in a depth of around 160 cm representing the old land surface. The former Ah horizon was most possibly removed before building up the wall. Below the wall (ii) a Luvic Phaeozem was found with dark brown and yellow brown clay coatings in the upper AhBt horizon. The lower humic Bt horizon reveals numerous fragments of clay coatings beside undisturbed yellow brown clay coatings. The buried Luvic Phaeozem is an archetype of the soil development stage at Roman times in that area. Since calcareous material was put on the upper decimetres of the wall, the following decalcification led to precipitation of carbonate in the humic Bt horizon of the Luvic Phaeozem and so conserved this stage of soil formation. The investigated (iii) Albic Luvisol situated about 30 m next to the wall section represents the present stage of soil development with (meanwhile) no macroscopic signs of the Chernozem/Phaeozem predecessors. To figure out soil development stages micromorphological data were combined with soil physical and chemical data as well as results from clay mineralogy. Due to secondary calcification the pH of the paleosol is around 7, whereas the occurrence of secondary chlorites in the upper part of the paleosol points at pH values ranging from 4-5 at Roman times.

Kühn, P.; Felix-Henningsen, P.

2009-04-01

271

Surface acoustic wave devices as passive buried sensors  

NASA Astrophysics Data System (ADS)

Surface acoustic wave (SAW) devices are currently used as passive remote-controlled sensors for measuring various physical quantities through a wireless link. Among the two main classes of designs-resonator and delay line-the former has the advantage of providing narrow-band spectrum informations and hence appears compatible with an interrogation strategy complying with Industry-Scientific-Medical regulations in radio-frequency (rf) bands centered around 434, 866, or 915 MHz. Delay-line based sensors require larger bandwidths as they consists of a few interdigitated electrodes excited by short rf pulses with large instantaneous energy and short response delays but is compatible with existing equipment such as ground penetrating radar (GPR). We here demonstrate the measurement of temperature using the two configurations, particularly for long term monitoring using sensors buried in soil. Although we have demonstrated long term stability and robustness of packaged resonators and signal to noise ratio compatible with the expected application, the interrogation range (maximum 80 cm) is insufficient for most geology or geophysical purposes. We then focus on the use of delay lines, as the corresponding interrogation method is similar to the one used by GPR which allows for rf penetration distances ranging from a few meters to tens of meters and which operates in the lower rf range, depending on soil water content, permittivity, and conductivity. Assuming propagation losses in a pure dielectric medium with negligible conductivity (snow or ice), an interrogation distance of about 40 m is predicted, which overcomes the observed limits met when using interrogation methods specifically developed for wireless SAW sensors, and could partly comply with the above-mentioned applications. Although quite optimistic, this estimate is consistent with the signal to noise ratio observed during an experimental demonstration of the interrogation of a delay line buried at a depth of 5 m in snow.

Friedt, J.-M.; Rétornaz, T.; Alzuaga, S.; Baron, T.; Martin, G.; Laroche, T.; Ballandras, S.; Griselin, M.; Simonnet, J.-P.

2011-02-01

272

Numerical simulation of thermal signatures of buried mines over a diurnal cycle  

Microsoft Academic Search

3D thermal and radiometric models have been developed to study the passive IR signature of a land mine buried under a rough soil surface. A finite element model is used to describe the thermal phenomena, including temporal variations, the spatial structure of the signature, and environmental effects. The Crank-Nicholson algorithm is used for time-stepping the simulation. The mine and the

Ibrahim K. Sendur; Brian A. Baertlein

2000-01-01

273

Wave-induced uplift force on a submarine pipeline buried in a compressible seabed  

Microsoft Academic Search

A two-dimensional finite-element simulation of the wave-induced hydrodynamic uplift force acting on a submarine pipeline buried in sandy seabed sediments subject to continuous loading of sinusoidal surface waves is presented. Neglecting inertia forces, a linear-elastic stress-strain relationship for the soil and Darcy's law for the flow of pore fluid are assumed. The model takes into account the compressibility of both

Waldemar Magda

1997-01-01

274

3D numerical simulation of the transport of chemical signature compounds from buried landmines  

Microsoft Academic Search

The transport of the chemical signature compounds from buried landmines in a three-dimensional (3D) array has been numerically modeled using the finite-volume technique. Compounds such as trinitrotoluene, dinitrotoluene, and their degradation products, are semi volatile and somewhat soluble in water. Furthermore, they can strongly adsorb to the soil and undergo chemical and biological degradation. Consequently, the spatial and temporal concentration

Maik Irrazabal; Ernesto Borrero; Julio G. Briano; Miguel Castro; Samuel P. Hernandez

2005-01-01

275

Numerical simulation of a buried hot crude oil pipeline during shutdown  

Microsoft Academic Search

In this paper a mathematical model is built for a buried hot crude oil pipeline during shutdown, and an unstructured grid\\u000a and polar coordinate grid are respectively applied to generating grids for the soil region and the three layers in the pipe\\u000a (wax layer, pipe wall, and corrosion-inhibiting coating). The governing equations are discretized using the finite volume\\u000a method. The

Cheng Xu; Bo Yu; Zhengwei Zhang; Jinjun Zhang; Jinjia Wei; Shuyu Sun

2010-01-01

276

Female-coerced monogamy in burying beetles  

Microsoft Academic Search

The reproductive interests of the sexes often do not coincide, and this fundamental conflict is believed to underlie a variety of sex-specific behavioral adaptations. Sexual conflict in burying beetles arises when a male and female secure a carcass that can support more offspring than a single female can produce. In such a situation, any male attracting a second female sires

Anne-Katrin Eggert; Scott K. Sakaluk

1995-01-01

277

THE ECOLOGY AND BEHAVIOR OF BURYING BEETLES  

Microsoft Academic Search

Burying beetles conceal small vertebrate carcasses underground and prepare them for consumption by their young. This review places their complex social behavior in an ecological context that focuses on the evolution of biparental care and communal breeding. Both males and females provide extensive parental care, and the major benefit of male assistance is to help defend the brood and carcass

Michelle Pellissier Scott

1998-01-01

278

Nestmate recognition in burying beetles: the \\  

Microsoft Academic Search

Burying beetles use small vertebrate carcasses as food for their larvae and defend these carcasses against intra- and interspecific competitors. Breeding associations on carcasses can consist of single females, heterosexual pairs, or various combinations of males and females. When a heterosexual pair collaborate in a breeding attempt, they do not typically exhibit aggressive behavior toward each other, but do attack

Anne-Katrin Eggert; Tobias Elsnera

2003-01-01

279

Stress Relaxation Phenomena in Buried Quantum Dots  

Microsoft Academic Search

We report on the results of experimental and theoretical investigation of mechanical stress relaxation in heterostructures with buried quantum dots. Quan- tum dot is viewed as a dilatational inclusion with eigenstrain (transformation strain) caused by crystal lattice mismatch between the dot and matrix materials. Stresses and energies for spheroid inclusions in an infinite medium, in a half-space, and in a

N. A. Bert; V. V. Chaldyshev; A. L. Kolesnikova; A. E. Romanov

280

Common trenching reduces damage to buried utilities  

Microsoft Academic Search

Since 1972 Niagara Mohawk Power Co. has established a utility corridor, installing 503 miles of buried gas mains and electric cables in a common trench. Their guidelines for common trenching included (1) the developer's responsibility for providing a subdivision map showing the location of each sidewalk, lot, and roadway, (2) an easement strip paralleling the front lot (street) line that

Alfiere

1982-01-01

281

In situ vitrification on buried waste  

SciTech Connect

In situ vitrification (ISV) is being evaluated as a remedial treatment technology for buried mixed and transuranic (TRU) wastes at the Subsurface Disposal Area (SDA) at Idaho National Engineering Laboratory (INEL) and can be related to buried wastes at other Department of Energy (DOE) sites. There are numerous locations around the DOE Complex where wastes were buried in the ground or stored for future burial. The Buried Waste Program (BWP) is conducting a comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) remedial investigation/feasibility study (RI/FS) for the Department of Energy - Field Office Idaho (DOE-ID). As part of the RI/FS, an ISV scoping study on the treatability of the SDA mixed low-level and mixed TRU waste is being performed for applicability to remediation of the waste at the Radioactive Waste Management Complex (RWMC). The ISV project being conducted at the INEL by EG&G Idaho, Inc. consists of a treatability investigation to collect data to satisfy nine CERCLA criteria with regards to the SDA. This treatability investigation involves a series of experiments and related efforts to study the feasibility of ISV for remediation of mixed and TRU waste disposed of at the SDA.

Bates, S.O.

1992-08-01

282

In situ vitrification on buried waste  

SciTech Connect

In situ vitrification (ISV) is being evaluated as a remedial treatment technology for buried mixed and transuranic (TRU) wastes at the Subsurface Disposal Area (SDA) at Idaho National Engineering Laboratory (INEL) and can be related to buried wastes at other Department of Energy (DOE) sites. There are numerous locations around the DOE Complex where wastes were buried in the ground or stored for future burial. The Buried Waste Program (BWP) is conducting a comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) remedial investigation/feasibility study (RI/FS) for the Department of Energy - Field Office Idaho (DOE-ID). As part of the RI/FS, an ISV scoping study on the treatability of the SDA mixed low-level and mixed TRU waste is being performed for applicability to remediation of the waste at the Radioactive Waste Management Complex (RWMC). The ISV project being conducted at the INEL by EG G Idaho, Inc. consists of a treatability investigation to collect data to satisfy nine CERCLA criteria with regards to the SDA. This treatability investigation involves a series of experiments and related efforts to study the feasibility of ISV for remediation of mixed and TRU waste disposed of at the SDA.

Bates, S.O.

1992-01-01

283

Nondestructive testing methods of detecting buried wastes  

Microsoft Academic Search

The hazardous materials waste problem has become critical: many buried waste disposal sites have been discovered and additional problems are being discovered daily. The U.S. Environmental Protection Agency (EPA) recently estimated that the cost of cleaning up hazardous chemical waste dumps in the U.S. might be as high as $50 billion. With such magnitudes, it is incumbent upon the technological

R. M. Koerner; A. E. Lord

1985-01-01

284

Present status of buried contact solar cells  

Microsoft Academic Search

Recent years have seen substantially increased performance for laboratory Silicon solar cells. The standard commercial screen-printing cell process sequence appears unable to take advantage of many of these improvements. Consequently, until recently, the efficiency of commercial cells has lagged considerably. The buried contact cell provides a commercial approach able to bridge this gap. During 1990 and 1991, the first results

M. A. Green; S. R. Wenham; J. Zhao; S. Bowden; A. M. Milne; M. Taouk; F. Zhang

1991-01-01

285

Helium Emanometry as an Indicator of Deeply Buried Uranium Deposits.  

National Technical Information Service (NTIS)

Helium emanometry has considerable potential for locating deeply buried uranium deposits. In order to determine whether near surface helium-4 anomalies are present over and in close proximity to deeply buried uranium deposits, helium measurements were car...

L. A. Pogorski G. S. Quirt

1979-01-01

286

Integrated Low Noise Buried Channel MOSFET Preamplifier Technology.  

National Technical Information Service (NTIS)

The objective of the effort was to establish the device design and processing guidelines necessary to fabricate an integrated buried channel MOS preamplifier using the current Texas Instruments buried channel MOSFET/CCD processing technology. Geometric, p...

D. G. Carrigan T. F. Cheek H. S. Fu W. F. Stephens A. F. Tasch

1977-01-01

287

Elementary GLOBE: Getting to Know Soil  

NSDL National Science Digital Library

A learning activity for the Scoop on Soils book in the Elementary GLOBE Series. Each student will make predictions about the properties of various soil samples. Then they will examine several types of soils and record their observations. Next, they will learn about soil profiles and horizons by both examining a soil sample in a jar and by creating a soil profile flip chart. The purpose of the activity is to provide the opportunity for students to ask questions and make observations about soil and introduce students to the properties of soil and to the concept of soil profiles and horizons. After completing this activity, students will know about soil's different properties and about soil profiles. Students will know that soils have different properties including texture, color, and size. They will know that soil forms layers based on these properties.

2008-12-01

288

Impact of Holocene dust aggradation on A horizon characteristics and carbon storage in loess-derived Mollisols of the Great Plains, USA  

Microsoft Academic Search

The amount and vertical distribution of soil organic carbon (SOC) storage is primarily a function of vegetation type and climate, with influence from soil and landscape properties and human activities. The influence of dust aggradation on landscapes during the Holocene has largely been ignored as a factor in long-term SOC storage. Dust aggradation is important to soil horizonation and C

Peter M. Jacobs; Joseph A. Mason

2005-01-01

289

Experimental Evaluation of the Apparent Temperature Contrast Created by Buried Mines as Seen by an IR Imager.  

National Technical Information Service (NTIS)

The detection of buried mines is a problem of prime interest internationally. One potential method to succeed in this task is to use passive IR imaging to form thermal images of the soil surface. Even though this technique has been intensively investigate...

J. R. Simard

1994-01-01

290

Laboratory Load Tests on Buried Flexible Pipe. Progress Report No. 6. Steel and Fiberglass Reinforced Resin Pipe in Sand Backfill.  

National Technical Information Service (NTIS)

Two steel pipe, one reinforced plastic mortar, and one fiberglass reinforced plastic pipe, each about 18 inches (46 centimeters) in diameter and 71 inches long were load-tested in a laboratory soil container. All pipe were buried in a sand backfill. Incre...

A. K. Howard

1973-01-01

291

Production and decay of evolving horizons  

NASA Astrophysics Data System (ADS)

We consider a simple physical model for an evolving horizon that is strongly interacting with its environment, exchanging arbitrarily large quantities of matter with its environment in the form of both infalling material and outgoing Hawking radiation. We permit fluxes of both lightlike and timelike particles to cross the horizon, and ask how the horizon grows and shrinks in response to such flows. We place a premium on providing a clear and straightforward exposition with simple formulae. To be able to handle such a highly dynamical situation in a simple manner we make one significant physical restriction—that of spherical symmetry—and two technical mathematical restrictions: (1) we choose to slice the spacetime in such a way that the spacetime foliations (and hence the horizons) are always spherically symmetric. (2) Furthermore, we adopt Painlevé Gullstrand coordinates (which are well suited to the problem because they are nonsingular at the horizon) in order to simplify the relevant calculations. Of course physics results are ultimately independent of the choice of coordinates, but this particular coordinate system yields a clean physical interpretation of the relevant physics. We find particularly simple forms for surface gravity, and for the first and second law of black hole thermodynamics, in this general evolving horizon situation. Furthermore, we relate our results to Hawking's apparent horizon, Ashtekar and co-worker's isolated and dynamical horizons, and Hayward's trapping horizon. The evolving black hole model discussed here will be of interest, both from an astrophysical viewpoint in terms of discussing growing black holes and from a purely theoretical viewpoint in discussing black hole evaporation via Hawking radiation.

Nielsen, Alex B.; Visser, Matt

2006-07-01

292

Improvement of Whitish Oasis Soil, Part 2: Preliminary Soil Bin Experiments with a Four-stage Subsoil Inverting Plough  

Microsoft Academic Search

The objective of this work was to develop a special machine, a four-stage subsoil inverting plough which would improve the permeability of whitish oasis soil by inverting the second horizon (Bca) and the third horizon (C) underground and by lowering the percentage of calcium carbonate (CaCO3) in the subsoil horizon. Specifically, the Bca horizon (with its high content of CaCO3)

G. Guo; K. Araya

2003-01-01

293

Pharmacologically Distinctive Behaviors other than Burying Marbles during the Marble Burying Test in Mice  

Microsoft Academic Search

In the marble burying test, we focused on the 5 distinctive behavioral parameters of mice other than burying marbles, i.e. digging, latency to the first digging, exploration around marbles, rearing and locomotor activity. Typical anxiolytics or antidepressants with different mechanisms, fluvoxamine (30 mg\\/kg, selective serotonin reuptake inhibitor), bupropion (60 mg\\/kg, noradrenaline and dopamine reuptake inhibitor), imipramine (60 mg\\/kg, tricyclic antidepressant)

Etsuko Hayashi; Kazuyoshi Kuratani; Mine Kinoshita; Hideaki Hara

2010-01-01

294

Speciation and distribution of cadmium and lead in salinized horizons of antrosols  

NASA Astrophysics Data System (ADS)

The utilization of intensive technologies for the vegetable cultivation in glass houses by the administration of high doses of organic fertilizes, the supra-dimensional irrigation and the maintaining of soil at high humidity state, in special in case of vicious drainage have as result the rapid degradation of morphological, chemical and physical characteristics of soils, concretized by: (i) decrease of structural aggregates stability; (ii) more dense packing of soil; (iii) accumulation of easy soluble salts (in special at superior horizons level); (iv) limitation of organic compounds and micro-elements biodisponibility. All these determined a significant reduction of productivity and of exploitation duration of soils from glass houses. These phenomena modified continuously the dynamic of speciation processes and inter-phases distribution, of heavy metals in soils from glass houses, and can determined a non-controlled accumulation of heavy metals, in special as mobile forms with high biodisponibility. Ours studied have been performed using soil profiles drawing from Copou-glass house, Iasi (Romania). Has been followed the modification of distribution for speciation forms of cadmium and lead (two heavy metals with high toxicity degree), between hortic antrosol horizons, and between chemical-mineralogical components of this, with the progressive salinization of superior horizons, in 2007-2008 period. The separation, differentiation and determination of cadmium and lead speciation forms was done by combined solid-liquid sequential extraction (SPE) and extraction in aqueous polymer-inorganic salt two-phase systems (ABS) procedure, presented in some of ours previous studies. After extraction, the total contents of the two heavy metals and fractions from these differential bonded by mineral and organic components of hortic antrosol have been determined by atomic absorption spectrometry. The specific interaction mechanisms of Cd and Pb with organic-mineral components of soils have been estimated on the basis of Raman and FT-IR spectra, recorded for fractions obtained after each extraction step. These data were correlated with those obtained by chemical analysis and UV-VIS spectrometry, and were used for to establish the type and weight of Cd and Pb speciation forms in studied antrosol. Our studies have been show that in medium and inferior horizons of hortic antrosols, the heavy metals have a general accumulation tendency, preferential by binding on organic matter and organic-mineral complexes, components with higher abundance in such type of soils. The selectivity and complexation mechanisms are controlled by speciation forms of the two metals. This phenomenon has two important consequences, the strong fixation of heavy metals in hortic antrosol and significant modification of structure and conformation of organic macromolecules. A specific phenomenon of hortic antrosols is that the accumulation rate of heavy metals is higher than levigation rate, and the mobile forms of these have a higher biodisponibility, being relative easy assimilated by plants. The progressive salinization of superior horizons of soils from glass houses, determined a sever perturbation of equilibrium between Cd and Pb speciation forms. In consequence these will have an accentuated migration tendency in superior horizons, as complexes with inorganic ligands, with a high mobility and biodsiponibility. The accumulation of soluble salts in superior horizons, and the formation of frangipane horizon (horizon of geochemical segregation of hortic antrosols) modified the ionic strength from soil solution and the thermodynamic activity of cadmium and lead species. Under these conditions, the levigation rate of cadmium and lead is higher than the accumulation rate, which means that the migration of these metals in soil solution occurs fast and in high concentrations. Acknowledgments The authors would like to acknowledge the financial support from Romanian Ministry of Education and Research (Project PNCDI 2-D5 no. 51045/07 an Project PNCDI 2-D5 no. 52141 / 08).

Bulgariu, D.; Bulgariu, L.; Astefanei, D.

2009-04-01

295

Black Hole Entropy and Isolated Horizons Thermodynamics  

NASA Astrophysics Data System (ADS)

We present a statistical mechanical calculation of the thermodynamical properties of (nonrotating) isolated horizons. The introduction of the Planck scale allows for the definition of a universal horizon temperature (independent of the mass of the black hole) and a well-defined notion of energy (as measured by suitable local observers) proportional to the horizon area in Planck units. The microcanonical and canonical ensembles associated with the system are introduced. Black hole entropy and other thermodynamical quantities can be consistently computed in both ensembles and results are in agreement with Hawking’s semiclassical analysis for all values of the Immirzi parameter.

Ghosh, Amit; Perez, Alejandro

2011-12-01

296

Occurrence of perched saturation and interflow over an argillic horizon in a low relief hillslope.  

SciTech Connect

Abstract. Many of the soils in the south-eastern US are characterized by an argillic, or clay horizon, that largely parallels the soil surface at depths ranging from a few centimeters to 100 cen-timeters. The degree to which these argillic horizons alter subsurface movement of infiltrated water is not well known. Interflow, or throughflow, is shallow lateral subsurface flow that moves over a horizon that restricts percolation. This research investigates how often and under what conditions a relatively deep (20-150+cm) argillic horizon on low slope (2-6%) hillsides causes interflow to oc-cur. Research is being conducted at the Savannah River Site, Aiken, South Carolina, on a small zero-order watershed. In the first phase of this research, a high resolution topographic map of the clay layer was developed. This map will be used to instrument designated “low” spots with max rise piezo-meters in order to determine if there is channelized subsurface flow. In situ conductivities of the clay layer and the surface horizons were measured using an Amoozegar meter, and bulk density samples were taken and measured. Along with soil topographic measurements, data-logging piezometers have been installed to measure the piezometric head above, in, and below the argillic horizon to further investigate interflow as a potential hydraulic routing mechanism. The stream that drains the catchment was instrumented with a 2’ H flume and data-logging pressure transducer to measure stream flow. Climate data including precipitation, barometric pressure and temperature, are being continuously collected in an open area approximately ¼ mile from the study site. Combining the shallow surface and subsurface piezometric heads with stream flow rates, we should be able to determine if and when the clay layer is contributing to inter-flow.

Greco, James; Jackson, Rhett, C.

2009-03-01

297

The effects of vegetation and burning on the chemical composition of soil organic matter in a volcanic ash soil as shown by 13C NMR spectroscopy. I. Whole soil and humic acid fraction  

Microsoft Academic Search

Soil samples were collected from the surface mineral horizon (Ah horizon) of four adjacent soils (sites I, II, III, IV) and one remote soil (site V) derived from volcanic ash in Japan. The four adjacent sites were managed as Miscanthus sinensis grassland for several hundred years by the use of annual burning to prevent the regrowth of native forest species.

A. Golchin; P. Clarke; J. A. Baldock; T. Higashi; J. O. Skjemstad; J. M. Oades

1997-01-01

298

[Viability of buried plant seeds from alpine plant communities (Northwest Caucasus): results of a five year experiment].  

PubMed

The experiment with seeds buried in soil has been carried out for 63 alpine plant species from the Northwest Caucasus. Seeds were mixed with native soils and placed in soil at the depth of 8-10 cm for five years. After excavation, seeds of 45 species did not germinate at all. Viability of eight species, four Carex species among them, exceeded 10%. These species are typical of Geranium-Hedysarum meadows and alpine snowbeds and form the main part of soil seed banks in these communities. PMID:23330400

Adzhiev, R K; Onipchenko, V G; Tekeev, D K

299

Static Massive Fields and the Horizon Surface.  

National Technical Information Service (NTIS)

The static massive scalar and vector fields are proved to be incompatible with the horizon surface. It points out the impossibility of the ''black holes'' creation in the presence of such fields. (Atomindex citation 09:376916)

G. V. Isaev

1976-01-01

300

Lessons Learned from the Deepwater Horizon Response.  

National Technical Information Service (NTIS)

Following the unprecedented federal response to the Deepwater Horizon (DWH) disaster, the National Institute for Occupational Safety and Health (NIOSH) conducted a review of the Institute's response activities. The purpose of this report is to evaluate th...

A. Tepper B. Bernard B. King D. Reissman G. DeBord J. Decker J. Gibbins J. Spahr L. Delaney M. Kitt M. H. Sweeney R. Funk T. Seitz V. Castranova

2011-01-01

301

Expanding Your Horizons in Science and Mathematics.  

National Technical Information Service (NTIS)

Through the presentation of its Expanding Your Horizons in Science and Mathematics career education conferences for secondary school young women, the Math/Science Network continues its efforts to remove the educational, psychological, and cultural barrier...

1985-01-01

302

Chinese-Made Horizon Display System.  

National Technical Information Service (NTIS)

After a successful flight test, a series of improvements on the horizon Display Fire Control System developed by the Electro Optical Research Institute of the Chinese Aeronautic Industrial Department were conducted. The three components are pilot display ...

L. Xi F. Xu

1987-01-01

303

Dynamic boundaries of event horizon magnetospheres  

Microsoft Academic Search

This Letter analyses three-dimensional (3D) simulations of Kerr black hole magnetospheres that obey the general relativistic equations of perfect magnetohydrodynamics (MHD). Particular emphasis is on the event horizon magnetosphere (EHM) which is defined as the the large-scale poloidal magnetic flux that threads the event horizon of a black hole. (This is distinct from the poloidal magnetic flux that threads the

Brian Punsly

2007-01-01

304

Numerical Simulations of Detonation of Buried and Flushed Anti-Tank Mines  

NASA Astrophysics Data System (ADS)

In order to determine the loads on mine-clearing devices generated by detonations of anti-tank mines, knowledge about the incident impulse and pressure generated in the air are needed. Dependent factors includes the mine’s depth of burial and the properties of the soil. Practical testing show that buried and flushed mines often result in more severe damages on vehicles than surface mines. Numerical simulations were performed to determine incident impulse and pressure history from detonations of fully buried and flushed anti-tank mines for dry porous soil and fully saturated soil. A multi-material Euler processor was used for the numerical studies, and the mine was modelled as a high explosive charge only. By using the Jones-Wilkins-Lee equation of state (EOS) the energy release was modelled. The air was modelled as an ideal gas EOS, and the dry porous soil were represented by a porous EOS together with pressure hardening yield surface. Finally, the fully saturated soil was modelled by shock EOS with a non-pressure hardening yield surface.

Laine, Leo; Ranestad, Øyvind; Sandvik, Andreas; Snekkevik, Asbjørn

2001-06-01

305

Burying by rats in response to aversive and nonaversive stimuli.  

PubMed

Previous investigations have shown that rats bury a variety of conditioned and unconditioned aversive stimuli. Such burying has been considered as a species-typical defensive reaction. In the present studies, rats buried spouts filled with Tabasco sauce, or condensed milk to which a taste aversion was conditioned, but did not bury water-filled spouts or spouts filled with a palatable novel food (apple juice) to which a taste aversion was not conditioned. However, in other experiments rats consistently and repeatedly buried Purina Rat Chow, Purina Rat Chow coated with quinine, and glass marbles. This indicates that a variety of stimuli, not all aversive or novel, evoke burying by rats. Whereas the behavior may reasonably be considered as a species-typical defensive behavior in some situations, the wide range of conditions that occasion burying suggests that the behavior has no single biological function. PMID:16812198

Poling, A; Cleary, J; Monaghan, M

1981-01-01

306

The Insects Colonisation of Buried Remains  

Microsoft Academic Search

\\u000a In our society, burial of a deceased person is a common habit in a normal situation. In opposition, manmade burial by authors\\u000a of homicide and\\/or their accomplices to hide the body of their victim is more seldom.\\u000a \\u000a \\u000a Exhumation of a buried corpse can be ordered by legal decision (second expert conclusion). It can also be accidental or required\\u000a by authorities

Emmanuel Gaudry

307

Buried caldera of mauna kea volcano, hawaii.  

PubMed

An elliptical caldera (2.1 by 2.8 kilometers) at the summit of Mauna Kea volcano is inferred to lie buried beneath hawaiite lava flows and pyroclastic cones at an altitude of approximately 3850 meters. Stratigraphic relationships indicate that hawaiite eruptions began before a pre-Wisconsin period of ice-cap glaciation and that the crest of the mountain attained its present altitude and gross form during a glaciation of probable Early Wisconsin age. PMID:17842285

Porter, S C

1972-03-31

308

Layerwise reaction at a buried interface  

SciTech Connect

X-ray diffraction was used to monitor the {ital in} {ital situ} reaction of Pd deposited on Si(111) at room temperature. An ordered silicide forms spontaneously beneath a poorly ordered overlayer. It is commensurate and strained at low coverage, but relaxes to an unstrained state above a critical thickness of 18 A. During both phases of growth sustained intensity oscillations are seen that correspond to a layerwise consumption of the substrate at the buried interface.

Bennett, P.A.; DeVries, B. (Department of Physics, Arizona State University, Tempe, Arizona 85287 (United States)); Robinson, I.K.; Eng, P.J. (AT T Bell Laboratories, Murray Hill, New Jersey 07974 (United States))

1992-10-26

309

Uncovering buried volcanoes at Yucca Mountain  

NASA Astrophysics Data System (ADS)

The hazard posed by small-volume basaltic volcanism to the proposed Yucca Mountain nuclear waste repository in Nevada has been a topic of scientific debate for well over a decade. In the past few years, debate has focused on the extent and age of buried volcanoes in alluvial-filled basins of the Yucca Mountain region (YMR) and their potential impact on volcanic hazard estimates.To address this issue, the U.S. Department of Energy (DOE) has sponsored an exceptionally high resolution aeromagnetic survey completed in 2004, and a presently ongoing drilling program to characterize the location, age, volume, and chemistry of buried basalt in the YMR (Figure 1). DOE has convened an expert panel that will use this information to update probabilistic volcanic hazard estimates originally obtained by experts in 1996. Partly on the basis of the unknown extent of buried volcanoes, Smith and Keenan [2005] suggested that volcanic hazard estimates might be 1-2 orders of magnitude higher than estimated by the 1996 expert elicitation.

Perry, Frank V.; Cogbill, Allen H.; Kelley, Richard E.

310

Simulation of Infiltration Into Organic-covered Permafrost Soils  

Microsoft Academic Search

Infiltration into frozen or unfrozen soils is critical in permafrost hydrology, controlling active layer soil water dynamics and influencing runoff. Quantifying the infiltration process in permafrost soils is made difficult by variable ground thawing and freezing and the layered soil profile that frequently has organic soils atop mineral horizons. Moreover, harsh environments impose technical and logistic difficulties in accurately monitoring

Y. Zhang; S. K. Carey; W. L. Quinton; J. R. Janowicz; G. N. Flerchinger

2008-01-01

311

Hydrogen soil dynamics in northern boreal and subarctic Sweden  

NASA Astrophysics Data System (ADS)

Wetland ecosystems store a large amount of organic carbon in the form of peat and are the largest natural source of CH4. Thawing of northern wetland permafrost results in an increase in the pool of soil carbon that is made available for decomposition processes and CH4 production. Some subarctic mire sites are also getting wetter as the climate warms. An increase in inundated areas in conjunction with increased amounts of organic matter could give rise to potential feedbacks to warming temperatures via increased emissions of reduced trace gases, such as CH4 and H2, to the atmosphere. H2 soil dynamics in peatlands and forests are complex because of the many microbial-mediated reactions driving H2 production and consumption. H2 couples oxidative and reductive processes in anaerobic environments. The aim of this project was to determine if high-latitude boreal and subarctic soils can change from a sink to a source of H2 to the atmosphere by identifying the microbial processes controlling the production and consumption of H2. Does H2 production and emissions to the atmosphere occur under temporary anoxia in organic -rich soils and soil horizons and do episodic weather events, particularly rain and freeze-thaw cycles, drive H2 production and release from natural soils due to the release of labile organic material and anaerobic conditions. Porewater soil gas profiles from different sub-habitats were determined in Stordalen mire in subarctic Sweden using buried ePTFE tubing and samples manually obtained using a stainless steel sipper. Trends in H2 concentration between the microporous tubing and sipper samples generally agree. The H2 concentration is higher in the tubing possibly due to preferential diffusion into the air-filled tubing by H2, which has a low solubility in water. The wettest site dominated by Eriophorum had the highest concentration of H2 with a maximum of 39.3 ppmv H2 at a depth of 30 cm. A mesic site dominated by Sphagnum had the next highest H2 concentration with 37.6 ppmv H2 at 20 cm below the ground surface. A Carex-dominated site also had increasing H2 concentration with depth. The concentrations of soil H2 in the dry palsa site were lower than ambient air indicating consumption at this site. Soil H2 was also measured in boreal forest soils, which typically act as a sink of atmospheric H2. Manual field sampling revealed that H2 concentrations were higher above the surface of the ground than at the base of the O horizon suggesting H2 deposition. An incubation experiment designed to test the interactions between soil moisture, temperature, and substrate addition indicated that warm, dry forest soils with added glucose are the highest consumers of H2 while warm, dry forest soils with no substrate addition produce the most H2. With the exception of the soil with the greatest glucose addition, the soils incubated at 20°C produced more H2 than soils at 12°C and 4°C.

Steele, K. J.; Crill, P. M.; Oquist, M. G.; Varner, R. K.

2011-12-01

312

Dynamics and relationships of Ca, Mg, Fe in litter, soil fauna and soil in Pinus koraiensis broadleaf mixed forest  

Microsoft Academic Search

The Liangshui Natural Reserve in Heilongjiang Province of China was selected as the study area. The authors collected the\\u000a samples of forest litter (Tilia amurensis, Fraxinus mandshurica, Pinus koraiensis, Acer mono, Betula costata, and mixed litter), soil in humus horizon (0–5cm) and soil horizon (5–20cm), and soil macrofauna (Oligochaeta, Geophiloporpha\\u000a and Juliformia) from 2001 to 2002. The role of soil

Bo Song; Xiuqin Yin; Yu Zhang; Weihua Dong

2008-01-01

313

The Q 10 relationship of microbial respiration in a temperate forest soil  

Microsoft Academic Search

Our objective was to study the effect of temperature on rates of soil respiration in the A-, E- and B-horizons of a temperate forest (Durham, North Carolina, USA). Soil samples were incubated for several months at 4, 15, 22 and 38°C and respiration was measured frequently during incubation. For each soil horizon, rates of CO2 evolution varied significantly with time

Julia Palmer Winkler; Robert S. Cherry; William H. Schlesinger

1996-01-01

314

Short-term Effects of Sewage-Sludge Compost on a Degraded Mediterranean Soil  

Microsoft Academic Search

In Mediterranean areas, often characterized by degraded soil due to recurrent fires and violent precipitation events, sewage sludge com- post could improve soil properties and stimulate plant succession pro- cesses. Most of the studies dealing with compost effects on soil properties only take into account the mineral horizon compartment, without studying compost effects on organic horizon properties. In this study,

Marie Larchevêque; Virginie Baldy; Nicolas Montès; Catherine Fernandez; Gilles Bonin; Christine Ballini

2006-01-01

315

In situ vitrification application to buried waste: Interim report of intermediate field tests at Idaho National Engineering Laboratory. Revision 1  

SciTech Connect

This report describes the two in situ vitrification field tests conducted in June and July 1990 at Idaho National Engineering Laboratory. In situ vitrification, an emerging technology for in- place conversion of contaminated soils into a durable glass and crystalline waste form, is being investigated as a potential remediation technology for buried waste. The overall objective of the two tests was to assess the general suitability of the process to remediate waste structures representative of buried waste found at Idaho National engineering Laboratory. In particular, these tests, as part of a treatability study, were designed to provide essential information on the field performance of the process under conditions of significant combustible and metal wastes and to test a newly developed electrode feed technology. The tests were successfully completed, and the electrode feed technology successfully processed the high metal content waste, indicating the process is a feasible technology for application to buried waste.

Callow, R.A.; Weidner, J.R. [EG and G Idaho, Inc., Idaho Falls, ID (United States); Thompson, L.E. [Pacific Northwest Lab., Richland, WA (United States)

1991-02-01

316

In situ vitrification application to buried waste: Interim report of intermediate field tests at Idaho National Engineering Laboratory  

SciTech Connect

This report describes the two in situ vitrification field tests conducted in June and July 1990 at Idaho National Engineering Laboratory. In situ vitrification, an emerging technology for in- place conversion of contaminated soils into a durable glass and crystalline waste form, is being investigated as a potential remediation technology for buried waste. The overall objective of the two tests was to assess the general suitability of the process to remediate waste structures representative of buried waste found at Idaho National engineering Laboratory. In particular, these tests, as part of a treatability study, were designed to provide essential information on the field performance of the process under conditions of significant combustible and metal wastes and to test a newly developed electrode feed technology. The tests were successfully completed, and the electrode feed technology successfully processed the high metal content waste, indicating the process is a feasible technology for application to buried waste.

Callow, R.A.; Weidner, J.R. (EG and G Idaho, Inc., Idaho Falls, ID (United States)); Thompson, L.E. (Pacific Northwest Lab., Richland, WA (United States))

1991-02-01

317

In situ vitrification application to buried waste: Interim report of intermediate field tests at Idaho National Engineering Laboratory  

SciTech Connect

This report describes the two in situ vitrification field tests conducted in July and July 1990 at Idaho National Engineering Laboratory. In situ vitrification, an emerging technology for in-place conversion of contaminated soils into a durable glass and crystalline waste form, is being investigated as a potential remediation technology for buried waste. The overall objective of the two tests was to assess the general suitability of the process to remediate waste structures representative of buried waste found at Idaho National Engineering Laboratory. In particular, these tests, as part of a treatability study, were designed to provide essential information field performance of the process under conditions of significant combustible and metal wastes and to test a newly developed electrode feed technology. The tests were successfully completed, and the electrode feed technology successfully processed the high metal content waste, indicating the process is a feasible technology for application to buried waste. 8 refs., 91 figs., 13 tabs.

Callow, R.A.; Weidner, J.R. (EG and G Idaho, Inc., Idaho Falls, ID (USA)); Thompson, L.E. (Pacific Northwest Lab., Richland, WA (USA))

1991-01-01

318

Near-field discrete-frequency microwave holographic imaging of buried ordnance  

NASA Astrophysics Data System (ADS)

Images of buried ordnance can accelerate remediation through identification. This paper presents images of a buried, inert projectile. The images are plan views, at fixed but variable depths. The images were formed by processing measured reflectance through Fourier transformation, backward propagation, and inverse transformation. Data were measured in two tests. Both tests utilized a towed array of seven antennas. One test, in 1995, used frequencies between 187.5 and 487.5 MHz; the best images were from the 387.5 MHz data. An earlier test, in 1994, used frequencies 200, 350, and 500 MHz; the best images were formed from the 500 MHz data. The procedures for the two sets of data differed in relative orientation of the sensor antennas and projectile; in addition, soil dielectric constant values differed. Image displays also differed in image data interpolation.

Nilles, James T.; Tricoles, Gus P.; Vance, Gary L.

1996-05-01

319

Field investigation and analysis of buried pipelines under various seismic environments. Technical report  

SciTech Connect

A research project is proposed in which the behavior of oil, water, sewer, and gas pipelines under various seismic environments, including seismic shaking and large ground deformation would be investigated. It is suggested that the investigation be conducted in the Beijing and Tangshan areas. Three major hazards to underground pipelines are identified: the effect of wave propagation; ground rupture and differential movement along fault lines; and soil liquefaction induced by ground shaking. Ruptures or severe distortions of the pipe are most often associated with fault movements, landslides, or ground squeeze associated with fault zones. A model is presented to evaluate the general longitudinal responses of buried pipelines, both segmented and continuous, subjected to ground shakings and vibrations. The results of these tests will be used to develop aseismic codes for buried pipelines.

Wang, L.R.L.

1982-08-01

320

Digital Horizons: A Plains Media Resource  

NSDL National Science Digital Library

The Digital Horizons website "provides, maintains, and preserves a wide range of historical and significant content related specifically to Fargo-Moorhead and broadly to North Dakota and Minnesota." In the "About Digital Horizons" link, visitors can read the foregoing purpose of the project, as well as the vision statement. The goals of the project, the audiences it's intended for--students, educators, internal staff, commercial users; and how to become a member of the project, are also in the "About Digital Horizons" link. The homepage has sections on "Managing Your Collection", about preserving or donating the photos, film, audio and textual materials one might have in one's home, and "Contributing Organizations", the list of which institutions have contributed to the project, which include Concordia College Archives, Prairie Public Broadcasting and the State Historical Society of North Dakota. Visitors can browse by "General Subject", "Collection", or "Popular Searches", via the homepage or the right hand side of any other main page.

321

Buried waste integrated demonstration configuration management plan  

SciTech Connect

This document defines plans for the configuration management requirements for the Buried Waste Integrated Demonstration (BWID) Program. Since BWID is managed programmatically by the Waste Technology Development Department (WTDD), WTDD Program Directive (PD) 1.5 (Document Preparation, Review, Approval, Publication, Management and Change Control) is to be followed for all internal EG&G Idaho, Inc., BWID programmatic documentation. BWID documentation generated by organizations external to EG&G Idaho is not covered by this revision of the Configuration Management Plan (CMP), but will be addressed in subsequent revisions.

Cannon, P.G.

1992-02-01

322

Early Presentation of Buried Bumper Syndrome  

PubMed Central

Percutaneous endoscopic gastrostomy (PEG) is a relatively safe and effective method of providing nutrition to patients with neurologic deficits or proximal gastrointestinal pathology. Complications that follow this common procedure include dislodgement, dysfunction, infection and aspiration. The “Buried Bumper Syndrome” (BBS) is an infrequent and late complication of PEG tubes that can result in tube dysfunction, gastric perforation, bleeding, peritonitis or death. The emergency physician should be aware of historical and exam features that suggest BBS and distinguish it from other, more benign, PEG-tube related complaints. We report a case of a woman presenting with BBS 3 weeks after having a PEG tube placed.

Geer, Walter; Jeanmonod, Rebecca

2013-01-01

323

Virtual environmental applications for buried waste characterization technology evaluation report  

SciTech Connect

The project, Virtual Environment Applications for Buried Waste Characterization, was initiated in the Buried Waste Integrated Demonstration Program in fiscal year 1994. This project is a research and development effort that supports the remediation of buried waste by identifying and examining the issues, needs, and feasibility of creating virtual environments using available characterization and other data. This document describes the progress and results from this project during the past year.

NONE

1995-05-01

324

SOIL AIR CARBON DIOXIDE CONCENTRATIONS IN A NEW ENGLAND SPRUCE-FIR FORESTS  

EPA Science Inventory

Research and modeling efforts to evaluate soil-soil solution chemical interactions must take into account solution equilibria with soil air CO2. Measurements of soil air CO2 and soil temperature were made in the major horizons of a forest soil in eastern Maine through the 1985 gr...

325

Soil Air Carbon Dioxide Concentrations in a New England Spruce-Fir Forests.  

National Technical Information Service (NTIS)

Research and modeling efforts to evaluate soil-soil solution chemical interactions must take into account solution equilibria with soil air CO2. Measurements of soil air CO2 and soil temperature were made in the major horizons of a forest soil in eastern ...

I. J. Fernandex P. A. Kosian

1987-01-01

326

Adsorption of pentachlorophenol by natural soils  

Microsoft Academic Search

The adsorption of pentachlorophenol, a listed hazardous substance, by natural soils was investigated at pH values of 4, 7, and 10 using various soils collected from the surface horizon. The effects of soil properties, such as organic carbon and fines content, were also studied and were found to have a significant positive correlation with the amount of solute adsorbed. Although

Christos Christodoulatos; George P. Korfiatis; Nazmi M. Talimcioglu; Mohammed Mohiuddin

1994-01-01

327

Classification of Near-Horizon Geometries of Extremal Black Holes  

NASA Astrophysics Data System (ADS)

Any spacetime containing a degenerate Killing horizon, such as an extremal black hole, possesses a well-defined notion of a near-horizon geometry. We review such near-horizon geometry solutions in a variety of dimensions and theories in a unified manner. We discuss various general results including horizon topology and near-horizon symmetry enhancement. We also discuss the status of the classification of near-horizon geometries in theories ranging from vacuum gravity to Einstein-Maxwell theory and supergravity theories. Finally, we discuss applications to the classification of extremal black holes and various related topics. Several new results are presented and open problems are highlighted throughout.

Kunduri, Hari K.; Lucietti, James

2013-09-01

328

Soil Science Education Homepage  

NSDL National Science Digital Library

This site covers numerous aspects of soil science and addresses many soil related issues at a level that can be presented to school age children. Several sections are devoted to the relationship between humans and soil in terms of agriculture, society, ecosystems, and why soil should be studied. Also included are photographs of different soil types or soil horizons with descriptions that explain what is being seen and what processes may have contributed to the soil characteristics. There are a host of activities that can be performed in the classroom or out in the field. The features of this site appear to be updated frequently and present different issues, activities, and discussions relating to soil.

2002-03-19

329

Laboratory data and model comparisons of the transport of chemical signatures from buried land mines/UXO  

NASA Astrophysics Data System (ADS)

Sensing the chemical signature emitted from the main charge explosives from buried landmines and unexploded ordnance (UXO) is being considered for field applications with advanced sensors of increased sensitivity and specificity. The chemical signature, however, may undergo many interactions with the soil system, altering the signal strength at the ground surface by many orders of magnitude. The chemidynamic processes are fairly well understood from many years of agricultural and industrial pollution soil physics research. Due to the unique aspects of the surface soil environment, computational simulation is being used to examen the breadth of conditions that impact chemical signature transport, from the buried location to a ground surface release. To provide confidence in the information provided by simulation modeling, laboratory experiments have been conducted to provide validation of the model under well-constrained laboratory testing conditions. A soil column was constructed with soil moisture monitoring ports, a bottom porous plate to regulate the soil moisture content, and a top plenum to collect the surface flux of explosive chemicals. The humidity of the air flowing through the plenum was set at about 50 percent RH to generate an upward flux of soil moisture. A regulated flux of aqueous phase 2,4-DNT was injected into the soil at about ten percent of the upward water flux. Chemical flux was measured by sampling with solid phase microextraction devices and analysis by gas chromatography/electron capture detection. Data was compared to model results from the T2TNT code, specifically developed to evaluate the buried landmine chemical transport issues. Data and model results compare exceptionally well providing additional confidence in the simulation tool.

Phelan, James M.; Gozdor, Matthew; Webb, Stephen W.; Cal, Mark

2000-08-01

330

Buried Waste Integrated Demonstration Plan. Revision 1  

SciTech Connect

This document presents the plan of activities for the Buried Waste Integrated Demonstration (BWID) program which supports the environmental restoration (ER) objectives of the Department of Energy (DOE) Complex. Discussed in this plan are the objectives, organization, roles and responsibilities, and the process for implementing and managing BWID. BWID is hosted at the Idaho National Engineering Laboratory (INEL), but involves participants from throughout the DOE Complex, private industry, universities, and the international community. These participants will support, demonstrate, and evaluate a suite of advanced technologies representing a comprehensive remediation system for the effective and efficient remediation of buried waste. The processes for identifying technological needs, screening candidate technologies for applicability and maturity, selecting appropriate technologies for demonstration, field demonstrating, evaluation of results and transferring technologies to environmental restoration programs are also presented. This document further describes the elements of project planning and control that apply to BWID. It addresses the management processes, operating procedures, programmatic and technical objectives, and schedules. Key functions in support of each demonstration such as regulatory coordination, safety analyses, risk evaluations, facility requirements, and data management are presented.

Kostelnik, K.M.

1991-12-01

331

Computational methods for shape restoration of buried objects in Compton backscatter imaging  

SciTech Connect

Image restoration techniques are studied for Compton backscatter imaging as applied to identification of a land mine buried in soil. Mathematical methods are developed to restore images, which include artifacts due to photon noise, soil surface irregularity, and vertical motion of the imaging system. The image restoration is formulated as an inverse photon transport problem. The forward photon transport is modeled by using a two-collision response function. The inverse problem then is solved by applying an iterative minimization algorithm, resulting in an estimation of characteristic parameters of objects. Mathematical relations among detector responses are derived by experimentally analyzing the detector response characteristics when there are soil surface irregularity and vertical motion of the imaging system. These are used to remove the artifacts from the images. The method successfully restores the geometrical feature of the object under simulated battlefield imaging conditions.

Watanabe, Yoichi; Monroe, J.; Keshavmurthy, S.; Jacobs, A.M.; Dugan, E.T. [Univ. of Florida, Gainesville, FL (United States). Dept. of Nuclear Engineering Sciences

1996-01-01

332

Adaptive Receding Horizon Control of Tubular Bioreactors  

Microsoft Academic Search

This paper presents a case study of application of an adaptive nonlinear predictive control algorithm to tubular bioreactors. According to the control strategy proposed, the system of PDEs describing the reactor is approximated by a lumped parameter model obtained using the Orthogonal Collocation Method. An adaptive receding horizon controller is then designed using Control Lyapunov Function methods. The design procedure

J. M. Igreja; J. M. Lemos; R. N. Silva

2005-01-01

333

Three Dimensional Receding Horizon Control for UAVs  

Microsoft Academic Search

This paper presents a receding horizon controller (RHC) that can be used to design trajectories for an aerial vehicle flying through a three dimensional terrain with obstacles and no-fly zones. To avoid exposure to threats, the paths are chosen to stay as close to the terrain as possible, but the vehicle can choose to pop-up over the obstacles if neces-

Yoshiaki Kuwata

2004-01-01

334

Euthanasia and distinctive horizons of moral reason  

Microsoft Academic Search

Rather than articulating and defending a particular normative stance concerning assisted suicide and euthanasia, attention here is directed toward the background, often tacit, interpretive horizons within which such judgements are formulated. Historical transformations can alter the contours of moral reflection, so that what is construed as “reasonable” and “common sensical” can shift over time. When core presuppositions constituting the public

Leigh Turner

1997-01-01

335

Receding Horizon Control for Airport Capacity Management  

Microsoft Academic Search

A major goal of air traffic management is to strategically control the flow of traffic so that the demand at an airport meets but does not exceed the operational capacity in a dynamic environment. This paper uses the concept of receding horizon control (RHC) to conduct real-time planning for airport capacity management (ACM). It is shown that RHC provides a

Wen-Hua Chen; Xiao-Bing Hu

2007-01-01

336

NIOSH Deepwater Horizon Roster Summary Report.  

National Technical Information Service (NTIS)

The explosion on the Deepwater Horizon oil rig on April 20, 2010, resulted in the deaths of 11 workers and injuries to another 17 workers. In the weeks and months afterward, large amounts of crude oil were emitted from the Macondo Well. As a result, tens ...

2011-01-01

337

CARBON DIOXIDE EMISSIONS FROM EXHUMED PETROCALCIC HORIZONS  

Technology Transfer Automated Retrieval System (TEKTRAN)

The second largest pool of terrestrial carbon is pedogenic CaCO3. In addition to being an important sink of atmospheric CO2, pedogenic carbonate has the potential to be an important source of atmospheric CO2. The cemented form of pedogenic carbonate (the petrocalcic horizon) develops in geomorphical...

338

Agriculture’s Ethical Horizon, book review  

Technology Transfer Automated Retrieval System (TEKTRAN)

Roughly 6.5 billion people inhabit the earth, but over 1 billion people regularly go hungry. This food shortfall poses an ethical dilemma for agriculture, and Agriculture's Ethical Horizon grapples with this dilemma. It argues that agricultural productivity has been the quintessential value of agr...

339

The stretched horizon and black hole complementarity  

Microsoft Academic Search

Three postulates asserting the validity of conventional quantum theory, semiclassical general relativity, and the statistical basis for thermodynamics are introduced as a foundation for the study of black-hole evolution. We explain how these postulates may be implemented in a ``stretched horizon'' or membrane description of the black hole, appropriate to a distant observer. The technical analysis is illustrated in the

Leonard Susskind; Lárus Thorlacius; John Uglum

1993-01-01

340

Thermal processing system concepts and considerations for RWMC buried waste  

SciTech Connect

This report presents a preliminary determination of ex situ thermal processing system concepts and related processing considerations for application to remediation of transuranic (TRU)-contaminated buried wastes (TRUW) at the Radioactive Waste Management Complex (RWMC) of the Idaho National Engineering Laboratory (INEL). Beginning with top-level thermal treatment concepts and requirements identified in a previous Preliminary Systems Design Study (SDS), a more detailed consideration of the waste materials thermal processing problem is provided. Anticipated waste stream elements and problem characteristics are identified and considered. Final waste form performance criteria, requirements, and options are examined within the context of providing a high-integrity, low-leachability glass/ceramic, final waste form material. Thermal processing conditions required and capability of key systems components (equipment) to provide these material process conditions are considered. Information from closely related companion study reports on melter technology development needs assessment and INEL Iron-Enriched Basalt (IEB) research are considered. Five potentially practicable thermal process system design configuration concepts are defined and compared. A scenario for thermal processing of a mixed waste and soils stream with essentially no complex presorting and using a series process of incineration and high temperature melting is recommended. Recommendations for applied research and development necessary to further detail and demonstrate the final waste form, required thermal processes, and melter process equipment are provided.

Eddy, T.L.; Kong, P.C.; Raivo, B.D.; Anderson, G.L.

1992-02-01

341

Contribution of organic matter and clay minerals to the cation exchange capacity of soils  

Microsoft Academic Search

The cation exchange capacity (CEC) at pH 7 was measured for samples of 347 A horizons and 696 B horizons of New Zealand soils. The mean CEC was 22.1 cmolc\\/kg for the A horizons and 15.2 cmolc\\/kg for the B horizons. Multiple regressions were carried out for CEC against organic carbon (C), clay content, and the content of seven groups

R. L. Parfitt; D. J. Giltrap; J. S. Whitton

1995-01-01

342

New France, New Horizons: On French Soil in America  

NSDL National Science Digital Library

Almost 400 years ago, France created its first permanent settlement in what would later become Canada. In doing so, the French embarked on a pattern of discovery and extended settlement that would continue until Britain eventually took control of the region in the late 18th century. Designed to celebrate and explore this rich history, this site was created by the Library and Archives Canada and the Direction des Archives de France in order to bring together over one million digitized images of documents, maps, plans, and other visual material related to this long period of French involvement in this part of North America. Here visitors can view a virtual exhibition, browse a list of other institutional links, and last (but certainly not least) search the massive database. The database is quite user-friendly, as visitors can elect to search by year (or time period), institutional location of document, or collection. For example, typing in Montreal returns 2900 documents alone, including numerous maps, government correspondence, and a number of city plans. The SVG Viewer plug-in allows users to zoom in, rotate, and manipulate documents in a number of ways, and is a welcome addition to this already remarkable online resource.

343

Stopping Rule for Forecast Horizons in Nonhomogeneous Markov Decision Processes.  

National Technical Information Service (NTIS)

A mixed integer program is formulated to determine whether a finite time horizon is a forecast horizon in a nonhomogeneous Markov decision process. A Bender's decomposition approach is used to solve this problem that evaluates the stopping rule, eliminate...

J. C. Bean W. J. Hopp I. Duenyas

1989-01-01

344

Eolian sedimentation and soil development on a semiarid to subhumid grassland, Tertiary Ogallala and Quaternary Blackwater Draw Formations, Texas and New Mexico High Plains  

SciTech Connect

Eolian sediments have accumulated as non-glacigenic loess and thin sand sheets on the Central and Southern High Plains grasslands of Texas and new mexico since the late Miocene. Locally as much as 110 m of eolian sediments with numerous paleosols are preserved in the Quaternary Blackwater Draw formation and the upper part of the Miocene-Pleiocene Ogallala formation. These sediments and paleosols, which cover more than 130,000 km{sup 2}, are similar to recent surface sediments and soils and record a long period of episodic eolian transport and sedimentation, and pedogenesis on a stable low-relief grass-covered landscape. Eolian sections, which comprise the fine sand to coarse silt lithofacies of the Ogallala formation, and the very fine to fine sand and sandy mud lithofacies of the Blackwater Draw formation, generally lack primary sedimentary structures. Grain size of Ogallala sediments decreases from west to east and grain size of Blackwater Draw sediments decreases from southwest to northeast. Soil horizonation is well developed in most sections, and buried calcic and argillic horizons are common. Calcic horizons are characterized by sharply increased CaCO{sub 3} content in the form of filaments, nodules, and petrocalcic horizons (calcretes). Argillic horizons are characterized by increased illuvial clay, pedogenic structure, and darker reddish hues. Rhizocretions are common locally. Open root tubules, which are typically less than 1 mm in diameter and characteristic of small plants like grasses, are present in all Ogallala and Blackwater Draw eolian sediments. Paleosols preserved in eolian sediments of the High Plains reflect periods of sedimentation followed by episodes of landscape stability and pedogenesis, and negligible sedimentation. Episodes of sedimentation and soil development likely resulted from cyclic decreases and increases in available moisture and vegetative cover. Eolian sediments were eroded and transported eastward during dry periods when vegetation was sparse in source areas, such as the western High Plains and the Pecos Valley. During humid periods more abundant vegetation probably protected source areas from deflation, and resulted in landscape stability across the High Plains.

Gustavson, T.C. [Univ. of Texas, Austin, TX (United States). Texas Archeological Research Lab.; Holliday, V.T. [Univ. of Wisconsin, Madison, WI (United States). Dept. of Geography

1999-05-01

345

Buried Craters In Isidis Planitia, Mars  

NASA Astrophysics Data System (ADS)

We have produced a topographic map of Isidis Planitia, which includes the Beagle 2 landing site, using interpolated Mars Orbiter Laser Altimeter (MOLA) data from the Mars Global Surveyor (MGS) spacecraft currently orbiting Mars. MOLA data have a vertical precision of 37.5 cm, a footprint size of 130 m, an along-track shot spacing of 330 m, and an across-track spacing that is variable and may be several kilometres. This has revealed subtle topographic detail within the relatively smooth basin of Isidis Planitia. Analysis of this map shows apparent wrinkle ridges that could be the volcanic basement to the basin and also several circular depressions with diameters of several to tens of kilometres which we interpreted as buried impact craters, comparable to the so-called stealth craters recognised elsewhere in the northern lowlands of Mars[1]. Stealth craters are considered to be impact craters subjected to erosion and/or burial. Some of these features in Isidis have depressions that are on the order of tens metres lower than their rims and are very smooth, and so are often not visible in MGS Mars Orbiter Camera (MOC) or Viking images of the basin. The Isidis stealth craters are not restricted to the Hesperian Vastitas Borealis formations like those detected elsewhere in the northern lowlands by Kreslavsky and Head [1], but are also found in a younger Amazonian smooth plains unit. It is generally believed that Isidis Planitia has undergone one or more episodes of sedi- ment deposition, and so these buried craters most likely lie on an earlier surface, which could be the postulated volcanic basement to the basin. Analysis of the buried craters may give some understanding of the thickness, frequencies and ages of sedimentation episodes within the basin. This information will be important in developing a context in which information from the Beagle 2 lander can be analysed when it arrives on Mars in December 2003. [1] Kreslavsky M. A. and Head J. W. (2001) LPS XXXII

Seabrook, A. M.; Rothery, D. A.; Wallis, D.; Bridges, J. C.; Wright, I. P.

346

Properties and Agricultural Potential of Skeletal Soils in Southern Thailand  

Microsoft Academic Search

A study on properties and agricultural potential of skeletal soils in Southern Thailand placed a major emphasis on representative skeletal soils that can be found in large extent, moderate extent and limited extent in the region. Study method included field investigation and pedon analysis of the representative soils and collecting soil samples from their genetic horizons, and laboratory analysis on

Irb Kheoruenromne; Sumitra Watana

347

Soil Warming and Carbon Loss from a Lake States Spodosol  

Microsoft Academic Search

Elevated soil temperatures may increase C loss from soils by accelerating microbial respiration and dissolved organic C leaching. We evaluated the effect of elevated soil temperatures on C losses from a forest Spodosol by incubating soil cores from surface (Oa + A + E) and subsurface (Bhs) horizons at two seasonal temperature regimes. One regime simulated the normal course of

Neil W. MacDonald; Diana L. Randlett; Donald R. Zak

1999-01-01

348

Development of a mechanistic model for the movement of chemical signatures from buried land mines/UXO  

NASA Astrophysics Data System (ADS)

The detection and removal of buried landmines and unexploded ordnance (UXO) is one of the most important problems facing the world today. Numerous detection strategies are being developed, including IR, electrical conductivity, ground- penetrating radar, and chemical sensor. Chemical sensor rely on the detection of explosive chemical molecules, which are transported from buried UXO/landmines by advection and diffusion in the soil. As part of this effort, numerical models are being developed to predict explosive chemical signature transport in soils. Modifications have been made to TOUGH2, a general-purpose porous media flow simulator, for application to the chemical sensing problem resulting in the T2TNT code. Understanding the fate and transport of explosive signature compounds in the solid will affect the design, performance, timing and operation of chemical sensing campaigns by indicating preferred sensing strategies.

Webb, Stephen W.; Pruess, Karsten; Phelan, James M.; Finsterle, Stefan A.

1999-08-01

349

Index theory and dynamical symmetry enhancement of M-horizons  

NASA Astrophysics Data System (ADS)

We show that near-horizon geometries of 11-dimensional supergravity preserve an even number of supersymmetries. The proof follows from Lichnerowicz type theorems for two horizon Dirac operators, the field equations and Bianchi identities, and the vanishing of the index of a Dirac operator on the 9-dimensional horizon sections. As a consequence of this, we also prove that all M-horizons with non-vanishing fluxes admit a sl( {2,{R}} ) subalgebra of symmetries.

Gutowski, J.; Papadopoulos, G.

2013-05-01

350

LOADING ON SIMULATED BURIED STRUCTURES AT HIGH INCIDENT OVERPRESSURES  

Microsoft Academic Search

A study was made of the factors affecting transmission of air-induced ; ground pressures and loadings produced on buried structures by such pressures. ; The test involved 68 devices composed of rigid cylinders with deformablediaphragm ; ends. Five diaphragm thicknesses were used to simulate structures of different ; flexmbilities. The drums were buried at depths ranging from 0 to 20

E. H. Jr. Bultmann; G. F. McDonough; G. K. Sinnamon

1960-01-01

351

Loading on simulated buried structures at high incident overpressures  

Microsoft Academic Search

This project was conducted to study the factors affecting transmission of air-induced ground pressures and loadings produced on buried structures by such pressures. The field test program involved 68 devices (drums) composed of rigid cylinders with deformable-diaphragm ends. Five diaphragm thicknesses were used to simulate structures of different flexibilities. The drums were buried at depths ranging from 0 to 20

E. H. Jr. Bultmann; G. F. McDonough; G. K. Sinnamon

1960-01-01

352

Habitat Fragmentation and Burying Beetle Abundance and Success  

Microsoft Academic Search

Four species of burying beetle (Nicrophorus marginatus F., N. tomentosus Weber, N. orbicollis Say and N. defodiens Mannerheim) are attracted to small, fresh mouse carcasses in northern Michigan. The number of burying beetles and their success (burial of a carcass) were greater in woodlands than in edge or field habitats. Species diversity was least in open fields as assessed by

Stephen T. Trumbo; Philip L. Bloch

2000-01-01

353

Buried waste remediation: A new application for in situ vitrification  

Microsoft Academic Search

Buried wastes represent a significant environmental concern and a major financial and technological challenge facing many private firms, local and state governments, and federal agencies. Numerous radioactive and hazardous mixed buried waste sites managed by the US Department of Energy (DOE) require timely clean up to comply with state or federal environmental regulations. Hazardous wastes, biomedical wastes, and common household

C. H. Kindle; L. E. Thompson

1991-01-01

354

Test plan for buried waste containment system materials  

Microsoft Academic Search

The objectives of the FY 1997 barrier material work at the Idaho National Engineering and Environmental Laboratory are to (1) select a waste barrier material and verify that it is compatible with the Buried Waste Containment System Process, and (2) determine if, and how, the Buried Waste Containment System emplacement process affects the material properties and performance (on proof of

J. Weidner; P. Shaw

1997-01-01

355

Acute buried bumper syndrome: an endoscopic peg tube salvage approach.  

PubMed

Acute buried bumper syndrome is an uncommon complication of percutaneous endoscopic gastrostomy (PEG) tube placement. If not recognized and treated appropriately, it can lead to serious complications including death. We report a case of an acute buried bumper syndrome, successfully managed with PEG tube repositioning through the original tract, without the need of replacement. PMID:22842323

Bhat, Ganesh; Suvarna, Deepak; Pai, Cannanore Ganesh

2010-05-01

356

Preliminary evaluation of the laser scalar gradiometer for buried minehunting  

Microsoft Academic Search

Fusion concepts using a magnetic sensor in combination with acoustic and optical sensors operating onboard an unmanned underwater vehicle (UUV) are under consideration to reacquire and confirm buried contacts detected in an initial sonar search. Two magnetic sensors are currently being developed by the Office of Naval Research for buried minehunting (BMH): Polatomic's Laser Scalar Gradiometer (LSG) and Quantum Magnetics'

T. R. Clem; P. S. Davis; R. J. McDonald; D. I. Overway; J. W. Purpura; L. Vaizer; D. King

2005-01-01

357

Uniphase buried-channel charge-coupled devices  

Microsoft Academic Search

The Uniphase operation of buried-channel CCDs with a single electrode system is described and practical structures are proposed. A stepped-oxide approach using strongly doped\\/thin-lightly doped\\/thick regions for the buried layer appears to be best suited for building a uniphase bulk-channel CCD with available technology.

R. M. BARSAN

1979-01-01

358

Physical Aspects of Quasi-Local Black Hole Horizons  

NASA Astrophysics Data System (ADS)

We discuss some of the physical aspects expected to be associated with black holes. These include Hawking radiation, horizon entropy and cosmic censorship. In particular we focus on whether these properties are more naturally associated to causally defined horizons or quasi-local horizons.

Nielsen, Alex B.

359

Some spacetimes containing non-rotating extremal isolated horizons  

NASA Astrophysics Data System (ADS)

Well-known results demonstrate the uniqueness of extremal isolated horizons (equivalently near-horizon spacetimes) in (3 + 1) dimensions. This paper briefly reviews some of these results and then explicitly constructs families of non-asymptotically flat, non-spherically symmetric spacetimes that nevertheless contain spherically symmetric extremal horizons that are isomorphic to those found in Reissner-Nordström spacetimes.

Booth, Ivan; Wenjie Tian, David

2013-07-01

360

Conditions for optimality of Naïve quantized finite horizon control  

Microsoft Academic Search

This paper presents properties of a control law which quantizes the unconstrained solution to a unitary horizon quadratic programme. This naïve quantized control law underlies many popular algorithms, such as ??-converters and decision feedback equalities, and is easily shown to be globally optimal for horizon one. However, the question arises as to whether it is also globally optimal for horizons

D. E. Quevedo; C. Müller; G. C. Goodwin

2007-01-01

361

Quantum Geometry of Isolated Horizons and Black Hole Entropy  

Microsoft Academic Search

Using the earlier developed classical Hamiltonian framework as the point of departure, we carry out a non-perturbative quantization of the sector of general relativity, coupled to matter, admitting non-rotating isolated horizons as inner boundaries. The emphasis is on the quantum geometry of the horizon. Polymer excitations of the bulk quantum geometry pierce the horizon endowing it with area. The intrinsic

Abhay Ashtekar; John C. Baez; Kirill Krasnov

2000-01-01

362

Integrated test schedule for buried waste integrated demonstration  

SciTech Connect

The Integrated Test Schedule incorporates the various schedules the Buried Waste Integrated Demonstration (BWID) supports into one document. This document contains the Federal Facilities Agreement and Consent Order schedules for the Idaho National Engineering Laboratory, Hanford Reservation, Oak Ridge Reservation, and Fernald Environmental Materials Center. Included in the Integrated Test Schedule is the Buried Waste Integrated Demonstration windows of opportunity'' schedule. The windows of opportunity'' schedule shows periods of time in which Buried Waste Integrated Demonstration Program-sponsored technology demonstrations could support key decisions in the Federal Facilities Agreement and Consent Order. Schedules for the Buried Waste Integrated Demonstration-sponsored technology task plans are categorized by technology area and divided by current fiscal year and out-year. Total estimated costs for Buried Waste Integrated Demonstration-sponsored Technology Task Plans for FY-92 through FY-97 are $74.756M.

Brown, J.T.; McDonald, J.K.

1992-05-01

363

Integrated test schedule for buried waste integrated demonstration  

SciTech Connect

The Integrated Test Schedule incorporates the various schedules the Buried Waste Integrated Demonstration (BWID) supports into one document. This document contains the Federal Facilities Agreement and Consent Order schedules for the Idaho National Engineering Laboratory, Hanford Reservation, Oak Ridge Reservation, and Fernald Environmental Materials Center. Included in the Integrated Test Schedule is the Buried Waste Integrated Demonstration ``windows of opportunity`` schedule. The ``windows of opportunity`` schedule shows periods of time in which Buried Waste Integrated Demonstration Program-sponsored technology demonstrations could support key decisions in the Federal Facilities Agreement and Consent Order. Schedules for the Buried Waste Integrated Demonstration-sponsored technology task plans are categorized by technology area and divided by current fiscal year and out-year. Total estimated costs for Buried Waste Integrated Demonstration-sponsored Technology Task Plans for FY-92 through FY-97 are $74.756M.

Brown, J.T.; McDonald, J.K.

1992-05-01

364

The ecology and behavior of burying beetles.  

PubMed

Burying beetles conceal small vertebrate carcasses underground and prepare them for consumption by their young. This review places their complex social behavior in an ecological context that focuses on the evolution of biparental care and communal breeding. Both males and females provide extensive parental care, and the major benefit of male assistance is to help defend the brood and carcass from competitors. As intensity and type of competition vary, so do the effectiveness and duration of male care. In many species, a single brood may be reared on large carcasses by more than one male and/or female. Limited reproductive opportunities, the greater effectiveness of groups in preventing the probability of brood failure (especially that caused by competing flies), and the superabundance of food on large carcasses have contributed to the evolution of this cooperative behavior. PMID:15012399

Scott, M P

1998-01-01

365

The horizon-entropy increase law for causal and quasi-local horizons and conformal field redefinitions  

NASA Astrophysics Data System (ADS)

We explicitly prove the horizon-entropy increase law for both causal and quasi-locally defined horizons in scalar-tensor and f(R) gravity theories. Contrary to causal event horizons, future outer trapping horizons are not conformally invariant and we provide a modification of trapping horizons to complete the proof, using the idea of generalized entropy. This modification means that they are no longer foliated by marginally outer trapped surfaces but fixes the location of the horizon under a conformal transformation. We also discuss the behaviour of horizons in 'veiled' general relativity and show, using this new definition, how to locate cosmological horizons in flat Minkowski space with varying units, which is physically identified with a spatially flat FLRW spacetime.

Faraoni, Valerio; Nielsen, Alex B.

2011-09-01

366

Organic and inorganic sulfur constituents of a forest soil and their relationship to microbial activity  

SciTech Connect

Sulfur (S) constituents, microbial biomass, and sulfohydrolase activity were determined for each soil horizon at both hardwood and conifer sites in a Becket soil (Adirondack Mountains, New York). Drying of soil before analysis altered the S constituents. There was a threefold increase (p<0.05) in sulfate in the organic horizons. Total S was greatest in the O horizons with 2,010 and 1,690 ..mu..g S/g in conifer and hardwood solums, respectively. Mineral soil had a maximum S concentration in the B21h horizon. Sulfate concentrations were a small proportion (<15%) of total S in B horizons. Organic S was dominant (93% of total S) in all horizons. Carbon-bonded S and ester sulfate were 74 and 18% of total S, respectively. Microbial biomass was greatest in the O1 horizon of both hardwood and conifer solums (59 and 70 mg biomass C per 100 g/sup -1/ dry mass, respectively). The B21h horizon contained the greatest biomass in the mineral soil. Sulfohydrolase activity exhibited the same distribution. Total S, carbon-bonded S, and ester sulfate were all positively correlated (p<0.05) to percent organic matter in the soil horizons. Correlations between microbial biomass and sulfohydrolase activity with organic S indicate the potential for microbial S transformations. Sulfate formation by mineralization may be more important than exogenous inputs. This has major implications for assessing the impact of atmospheric S deposition on soils.

David, M.B.; Mitchell, M.J.; Nakas, J.P.

1982-07-01

367

Wave-induced uplift force acting on a submarine buried pipeline: Finite element formulation and verification of computations  

Microsoft Academic Search

This paper describes a two-dimensional finite element model developed to simulate the wave-induced hydrodynamic uplift force acting on a submarine pipeline buried in sandy seabed sediments subjected to continuous loading of sinusoidal surface waves. Neglecting inertia forces, a linear-elastic stress-strain relationship for the soil, and Darcy's law for the flow of pore fluid are assumed. The model takes into account

W. Magda

1996-01-01

368

Viscous flow lobes in central Taylor Valley, Antarctica: Origin as remnant buried glacial ice  

NASA Astrophysics Data System (ADS)

Viscous flow lobes are common throughout the McMurdo Dry Valleys (MDV) of Antarctica. These features have been described as rock glaciers, gelifluction lobes, solifluction lobes, talus mobilized by pore ice and/or segregation ice, and debris-covered glaciers. We investigate the origin, modification, and flow of a 2-km-long lobe (East Stocking Lobe or ESL) along the north wall of central Taylor Valley using field mapping techniques, shallow seismic surveys, time-dependent displacement surveys, and isotopic analyses of buried-ice samples. On the basis of these integrated analyses, we show that the ESL is cored with remnant glacier ice, most probably derived from an advance of nearby Stocking Glacier ˜ 130 kyr BP. Seismic data, coupled with results from ice-flow modeling assuming plastic flow of clean ice, suggest that the buried core of glacier ice is ˜ 14- to 30-m thick. Near its terminus, the ESL flows at a rate of ˜ 2.4 to 6.7 mm a - 1 . The loose drift that caps the buried ice (typically < 1 m thick) is composed of moderately stratified sand- and gravel-sized clasts; it is dry (1-3% soil gravimetric water content; GWC), except near ephemeral stream channels and the margins of melting snow banks (6-25% GWC). Stable isotopic analyses of samples from the upper 30 cm of the ice lie on a slope of ˜ 5.8 (when plotted on a ?D vs. ?18O graph), well below the local meteoric water line of 7.75, suggesting modification by freeze/thaw processes and evaporation/sublimation. Measured air and soil temperatures show that intermittent melting is most likely possible during summer months where buried ice is ? 35 cm below the ground surface. Morphological comparisons with ice-cored deposits in upland regions of the Dry Valleys, e.g., Mullins and Beacon Valleys (30 km inland and ˜ 500 m higher in elevation), and near the coast (40 km distant and ˜ 500 m lower) reveal marked contrasts in the style of near-surface ice degradation and cryoturbation. From these morphological comparisons, we infer that buried-ice deposits in the stable upland zone have not experienced the relatively warm climate conditions now found at the ESL and at lower elevations in the Dry Valleys region (e.g. sustained summertime temperatures of ?-4 °C) for the last several million years.

Swanger, Kate M.; Marchant, David R.; Kowalewski, Douglas E.; Head, James W., III

2010-08-01

369

Amazon soils : a reconnaissance of the soils of the Brazilian Amazon region  

Microsoft Academic Search

The study deals with soils of the Brazilian part of the Amazon basin. Most soils are Latosols, some with soft or hardened plinthite. The Latosols are characterized by a latosolic B horizon as defined in Brazil.Plinthite, its formation and morphology were extensively described. Five main types of hard plinthite were distinguished. The rather uniform soils of the Amazon Planalto proved

W. G. Sombroek

1966-01-01

370

Testing soil for corrosiveness  

SciTech Connect

This article discusses soil conditions and elements that are common to most types of buried or submerged structures. It provides an overview of the parameters which determine the corrosiveness of a soil. Soil resistivity test data is the best data available for determining soil corrosiveness. Analysis of resistivity data should concentrate on changes in resistivity rather than absolute values of resistivity. Chloride concentrations, pH, and total acidity should be known for soil evaluation for most construction materials. Sulfate concentrations and hydroxyl ion concentrations are of concern in dealing with concrete structures. Redox potential sulfides and moisture values should not be used indiscriminately in soil analysis. An experienced corrosion engineer can identify the need for the tests and should supervise testing to ensure a high degree of accuracy.

Robinson, W.C. (Intermountain Corrosion Service, Inc., Tacoma, WA (United States))

1993-04-01

371

Phosphorus fertilization by active dust deposition in a super-humid, temperate environment—Soil phosphorus fractionation and accession processes  

NASA Astrophysics Data System (ADS)

The inventory of soil phosphorus (P) is subject to significant changes over time. The main primary form, bedrock-derived apatite P, becomes progressively lost through leaching, or transformed into more immobile and less plant-accessible, secondary organic and mineral forms. Here we studied the rejuvenating effect of dust deposition on soil P along an active dust flux gradient downwind of a braided river. Along the gradient, we measured soil P fractions to 50 cm depth of six Spodosols and one Inceptisol, supplemented by tree foliage P concentrations. While an increasing dust flux correlates with a twofold increase of foliar P and soil organic P along the gradient, apatite P declines from ~50 to 3 g m-2 and total P shows no response. Compared to dust-unaffected Spodosols, depth distribution of total P becomes increasingly uniform and organic P propagates deeper into the soil under dust flux. Further, the effect of topsoil P eluviation attenuates due to higher organic P content and the zone of high apatite P concentrations associated with un-weathered subsoil becomes progressively removed from the upper 50 cm. We interpret these patterns as being consistent with upbuilding pedogenesi and conclude that dust-derived mineral P is assimilated in the organic surface horizon and does not reach the mineral soil. Dust-derived mineral P is temporarily stored in the living biomass and returns to the soil with plant and microbial detritus as organic P, which is subsequently buried by further dust increments. We further conclude that (1) the efficiency of P fertilization of the ecosystem by dust accession is higher than through P advection in dust-unaffected Spodosols and (2) organic P may serve as an important source of labile P in a high-leaching environment.

Eger, Andre; Almond, Peter C.; Condron, Leo M.

2013-01-01

372

Fate and Speciation of Gasoline-Derived Lead in Organic Horizons of the Northeastern USA  

SciTech Connect

Although legislation in the late 1970s significantly reduced atmospheric lead (Pb) inputs to ecosystems in North America, organic (O) horizons in forests of the northeastern USA still contain up to 30 kg of gasoline-derived Pb ha{sup -1}. The residence time, geochemical behavior, and fate of this contaminant Pb in soils is poorly understood. Here we use forest floor time series data and synchrotron-based X-ray techniques to examine the mobility and speciation of Pb in O horizons collected from remote sites across the northeastern USA. At high elevation (>800 m) sites in Vermont and New York, samples collected from similar locations in 1980, 1990, and early 2000 had indistinguishable Pb contents, ranging ({+-}1{sigma}) from 11 to 29 kg Pb ha{sup -1}. However, at lower elevation and lower latitude sites with mixed vegetation, significant decreases in Pb amount were observed during the two-decade study period. Lower elevation sites ranged from 10 to 20 kg Pb ha{sup -1} in 1980, and from 2 to 10 kg Pb ha{sup -1} 20 yr later. Lead-enriched soil grains were determined to be amorphous with microfocused X-ray diffraction, and Pb concentrations correlated well with Fe on maps generated via microfocused X-ray fluorescence. Bulk Pb L{sub III}-edge X-ray absorption spectroscopy of coniferous O horizon samples indicate that Pb is binding to iron-rich soil particles by inner-sphere complexes, most likely to amorphous Fe oxides. Based on our paired regional and microscopic observations, we conclude that Pb is strongly retained in well-drained O horizons, and mobility is governed by decomposition and colloidal transport.

Kaste,J.; Bostick, B.; Friedland, A.; Schroth, A.; Siccama, T.

2006-01-01

373

Laboratory Load Tests on Buried Flexible Pipe-Progress Report No. 6. Steel and Fiberglass Reinforced Resin Pipe in Sand Backfill.  

National Technical Information Service (NTIS)

Two steel pipe, one reinforced plastic mortar, and one fiberglass reinforced plastic pipe, each about 18 inches (46 centimeters) in diameter and 71 inches long were load-tested in a laboratory soil container. All pipe were buried in a sand backfill. Incre...

A. K. Howard

1973-01-01

374

The Experimental Earthwork at Wareham, Dorset after 33 Years: Retention and Leaching of Phosphate Released in the Decomposition of Buried Bone  

Microsoft Academic Search

The 33-year section of the Wareham Experimental Earthwork provided a unique opportunity to investigate the retention and leaching of phosphate released as bone rapidly decomposes in a lowland heath environment. The soils are extremely acidic, sandy, Fe-deficient podzols, with naturally very low, though variable, phosphate concentrations. Phosphate released from bone buried (i) on the old ground surface beneath the bank

J. Crowther

2002-01-01

375

Soil organic carbon and CO2 respiration at subzero temperature in soils of Arctic Alaska  

Microsoft Academic Search

Carbon dioxide respiration rates were measured in the laboratory at -2°C for 88 arctic Alaska soil horizon samples. Soil horizon samples represented most ATLAS C-flux study sites to a 1-m depth. Sites represented extend across the Alaska Arctic, from tundra at Prudhoe Bay (70°N, 149°W) in the northeast to the tundra-forest transition zone of the Seward Peninsula (64°N, 163°W) in

G. J. Michaelson; C. L. Ping

2003-01-01

376

Soil organic carbon and CO2 respiration at subzero temperature in soils of Arctic Alaska  

Microsoft Academic Search

Carbon dioxide respiration rates were measured in the laboratory at ?2°C for 88 arctic Alaska soil horizon samples. Soil horizon samples represented most ATLAS C-flux study sites to a 1-m depth. Sites represented extend across the Alaska Arctic, from tundra at Prudhoe Bay (70°N, 149°W) in the northeast to the tundra–forest transition zone of the Seward Peninsula (64°N, 163°W) in

G. J. Michaelson; C. L. Ping

2003-01-01

377

Holography and hydrodynamics: diffusion on stretched horizons  

Microsoft Academic Search

We show that long-time, long-distance fluctuations of plane-symmetric horizons exhibit universal hydrodynamic behavior. By considering classical fluctuations around black-brane backgrounds, we find both diffusive and shear modes. The diffusion constant and the shear viscosity are given by simple formulas, in terms of metric components. For a given metric, the answers can be interpreted as corresponding kinetic coefficients in the holographically

Pavel Kovtun; Dam T. Son; Andrei O. Starinets

2003-01-01

378

Quantum amplification effect in a horizon fluctuation  

NASA Astrophysics Data System (ADS)

The appearance of a few unevenly spaced bright flashes of light on top of Hawking radiation is the sign of the amplification effect in black hole horizon fluctuations. Previous studies on this problem suffer from the lack of considering all emitted photons in the theoretical spectroscopy of these fluctuations. In this paper, we include all of the physical transition weights and present a consistent intensity formula. This modifies a black hole radiation pattern.

Ansari, Mohammad H.

2010-05-01

379

Gribov horizon beyond the Landau gauge  

NASA Astrophysics Data System (ADS)

Gribov and Zwanziger proposed a modification of Yang–Mills theory in order to cure the Gribov copy problem. We employ field-dependent BRST transformations to generalize the Gribov–Zwanziger model from the Landau gauge to general R? gauges. The Gribov horizon functional is presented in explicit form, in both the non-local and local variants. Finally, we show how to reach any given gauge from the Landau one.

Lavrov, Peter M.; Lechtenfeld, Olaf

2013-10-01

380

Chemical Sensing for Buried Landmines - Fundamental Processes Influencing Trace Chemical Detection  

SciTech Connect

Mine detection dogs have a demonstrated capability to locate hidden objects by trace chemical detection. Because of this capability, demining activities frequently employ mine detection dogs to locate individual buried landmines or for area reduction. The conditions appropriate for use of mine detection dogs are only beginning to emerge through diligent research that combines dog selection/training, the environmental conditions that impact landmine signature chemical vapors, and vapor sensing performance capability and reliability. This report seeks to address the fundamental soil-chemical interactions, driven by local weather history, that influence the availability of chemical for trace chemical detection. The processes evaluated include: landmine chemical emissions to the soil, chemical distribution in soils, chemical degradation in soils, and weather and chemical transport in soils. Simulation modeling is presented as a method to evaluate the complex interdependencies among these various processes and to establish conditions appropriate for trace chemical detection. Results from chemical analyses on soil samples obtained adjacent to landmines are presented and demonstrate the ultra-trace nature of these residues. Lastly, initial measurements of the vapor sensing performance of mine detection dogs demonstrates the extreme sensitivity of dogs in sensing landmine signature chemicals; however, reliability at these ultra-trace vapor concentrations still needs to be determined. Through this compilation, additional work is suggested that will fill in data gaps to improve the utility of trace chemical detection.

PHELAN, JAMES M.

2002-05-01

381

Foliar free polyamine and inorganic ion content in relation to soil ...  

Treesearch

Author: Minocha, Rakesh; Long, Stephanie; Magill, Alison H.; Aber, John; ... Total N content was positively correlated with polyamines in the needles (P ? 0.05). ... soil horizons and positively correlated with Ca and Mg in the soil solution (P ...

382

New Horizons At Jupiter: Overview Of Results  

NASA Astrophysics Data System (ADS)

NASA's New Horizons spacecraft has provided new data on the Jupiter system, acquiring new perspectives of the giant planet's atmosphere, rings, moons and magnetosphere. These new views include the closest look yet at the Earth-sized "Little Red Spot" storm churning materials through Jupiter's cloud tops; detailed images of small satellites herding dust and boulders through Jupiter's faint rings; and of volcanic eruptions and circular mega- troughs on the planet's largest moons. New Horizons came to within 2.3 million kilometers of Jupiter on February 28 of this year, using the planet's gravity to trim three years from its travel time to Pluto. For several weeks before and after this closest approach, the spacecraft trained its seven instruments on Jupiter and its four largest moons, storing data from nearly 700 observations and gradually sending that information back to Earth. New Horizons completed its visit to the Jupiter system with its unprecedented flight down Jupiter's enormous magnetotail. The presentation will cover a number of Jupiter system studies - observations such as Jovian meteorology, studies of the great and little red spots, auroral studies, and magnetospheric sampling. Surface mapping, compositional mapping and atmospheric studies of Jupiter's largest moons are to be covered as well. A detailed report of the findings for the volcanic moon Io will be given in a companion presentation.

Moore, J. M.

2007-12-01

383

Effects of soil water content and soil texture on radar and infrared landmine sensors: implications for sensor fusion  

Microsoft Academic Search

The performance of most, if not all, sensors for the detection of buried landmines is influenced by the properties of the soil that surrounds the mine. Most field soils are highly heterogeneous, in terms of texture, pore space quantity and distribution, composition, or water content. Soil heterogeneity can affect different modalities of landmine sensors and the temporal and spatial variability

R. L. Van Dam; B. Borchers; J. M. H. Hendrickx; R. S. Harmon

384

Comparison of groundwater colloids in adjoining soils of Florida flatwoods  

SciTech Connect

Colloids in soil water are a constituent of natural geochemical fluxes and have the potential to facilitate contaminant transport, but few data are available on their composition and concentration. This study addresses how the composition and concentration of groundwater solids relate to hydrological and soil morphological variables of the Florida flatwoods landscape. Groundwater from saturated soil horizons was sampled biweekly for 1 year along an Aquod/Udult boundary using piezometers designed specifically to minimize disturbance and to permit the valid assessment of suspended solids. Readily dispersible clay from core samples of soil horizons was collected and quantified. Groundwater and soil colloids were analyzed physically, chemically, and mineralogically. Aquod groundwater had consistently lower pH, higher electrical conductivity, and more total solids (TS) and organic carbon (OC) than did Udult groundwater. Significant decreases in both TS and OC concentrations in groundwater occurred with depth for both soils. In contrast, the mineralogy of groundwater colloids was insensitive to soil and horizon differences. Quartz dominated inorganic colloid fractions in groundwater samples from all horizons, even in argillic horizons where clay fractions contained little or no quartz. No statistical correlations were found between masses of groundwater colloids and soil water-dispersible clay. However, the proportion of organic carbon was higher in groundwater than in soil matrices. Results are consistent with carbon and colloidal quartz movement in shallow groundwater of the soil studied and document that natural colloid and solute fluxes can be highly soil specific.

Tan, Z.X.; Harris, W.G.; Ma, L.Q.

2000-02-01

385

Conservation of soil organic matter through cryoturbation in arctic soils in Siberia  

Microsoft Academic Search

Cryoturbation (mixing of soil layers due to repeated freeze-thaw processes) is a major soil forming process in arctic regions, which may contribute to long-term storage of C in soils of northern latitudes. Our goal was to determine the effect of subduction of organic matter by cryoturbation on microbial decomposition processes in tundra soils. Buried layers were situated at 30-60 cm

Christina Kaiser; Hildegard Meyer; Christina Biasi; Olga Rusalimova; Pavel Barsukov; Andreas Richter

2007-01-01

386

Conservation of soil organic matter through cryoturbation in arctic soils in Siberia  

Microsoft Academic Search

Cryoturbation (mixing of soil layers due to repeated freeze-thaw processes) is a major soil forming process in arctic regions, which may contribute to long-term storage of C in soils of northern latitudes. Our goal was to determine the effect of subduction of organic matter by cryoturbation on microbial decomposition processes in tundra soils. Buried layers were situated at 30–60 cm

Christina Kaiser; Hildegard Meyer; Christina Biasi; Olga Rusalimova; Pavel Barsukov; Andreas Richter

2007-01-01

387

Effects of acid rain on ion leaching in a danish forest soil  

Microsoft Academic Search

The mobility of major cations (H+, ammonium, Al, Ca, Na, Mg, K, Fe), heavy metals (Mn, Zn, Ni, Cd) and anions (chloride, sulphate and nitrate) was studied in the laboratory in an acidified brown soil from a Norway spruce forest. Lysimeters containing undisturbed soil columns of the A-horizon and the A- plus B-horizon were watered with 540 mm of throughfall

N. E. v. Freiesleben; L. Rasmussen

1986-01-01

388

Experimental evidence for mobility of Zr and other trace elements in soils  

Microsoft Academic Search

A Soxhlet extraction was carried out over a period of 27 d on a column comprising 3 cm of quartz overlain by 4 cm of soil from the B horizon and then 1 cm of soil from the A horizon of a granitic podzol. Major and trace elements were leached from the column and accumulated in a reservoir at the

Mark E Hodson

2002-01-01

389

Mineral magnetic properties of acid gleyed soils under oak and Corsican Pine  

Microsoft Academic Search

A comparison is made of the magnetic properties of acid gleyed soils under two woodland stands, oak (Quercus robur) and Corsican Pine (Pinus laricio). Twenty-five soil profiles under each type were sampled and analysed in three layers within designated horizons. The results show that in the surface (organic) horizon the main magnetic component is probably derived from fly-ash, and that

J. A. Dearing; J. A. Lees; C. White

1995-01-01

390

Validation of surface soil moisture from AMSR-E using auxiliary spatial data in the transboundary Indus Basin  

Microsoft Academic Search

Information on soil moisture is vital to describe various hydrological processes. Soil moisture parameters are normally measured using buried sensors in the soil. Alternatively, spatial and temporal characteristics of surface soil moisture are estimated through satellites. Advanced Microwave Scanning Radiometer on the Earth Observing System (AMSR-E) is one of such satellites that estimate surface soil moisture in an operational context.

M. J. M. Cheema; W. G. M. Bastiaanssen; M. M. Rutten

2011-01-01

391

Stabilized soil organic carbon pools in subsoils under forest are potential sinks for atmospheric CO2  

Technology Transfer Automated Retrieval System (TEKTRAN)

The soil organic carbon (SOC) pool stored in sub-soil horizons in forests plays an important role in the global C cycle. Strategies are needed to increase the sub-soil SOC pool in forests because the turnover time of SOC increases with increase in soil depth as sub-soil SOC is chemically and physica...

392

Soil warming and carbon loss from a lake states Spodosol  

SciTech Connect

Elevated soil temperatures may increase C loss from soils by accelerating microbial respiration and dissolved organic C leaching. The authors evaluated the effect of elevated soil temperatures on C losses from a forest Spodosol by incubating soil cores from surface (Oa + A + E) and subsurface (Bhs) horizons at two seasonal temperature regimes. One regime simulated the normal course of soil temperatures in northern lower Michigan, and the other simulated soil temperatures representing an amount of warming the might occur under some global warming theory calculations. The authors measured the amounts of CO{sub 2}-C respired and dissolved organic C leached from the soil cores during a 33-wk period. Microbial respiration rates, after adjustment for variation in initial rates, were significantly increased by soil warming and were greater in surface than in subsurface horizons. Warming significantly increased cumulative C respired, with greater losses from surface soils as compared with subsurface soils. Mean quantities of dissolved organic C leached, ranging from 2.3 to 3.2 mg C g{sup {minus}1} C, did not differ significantly by soil horizon or temperature regime. Increased microbial respiration in surface soil horizons was the process most responsive to soil warming in the Spodosol samples examined. Whether this is a short-term effect that would disappear once pools of labile C are exhausted, or represents a long-term response to soil warming, remains uncertain.

MacDonald, N.W. [Grand Valley State Univ., Allendale, MI (United States). Dept. of Biology; Randlett, D.L.; Zak, D.R. [Univ. of Michigan, Ann Arbor, MI (United States). School of Natural Resources and Environment

1999-01-01

393

SWBCM: a soil water balance capacity model for environmental applications in the UK  

Microsoft Academic Search

The paper presents a daily-time step, multi-horizon capacity model of soil-water balance (SWBCM—Soil Water Balance Capacity Model) suitable for ecological and environmental applications investigating the spatial and temporal variability of soil water content determined by changes in soil hydraulic conductivity, soil water storage capacity and the pathways of water movement through the soil and across soil types. SWBCM simulates soil

Samuel P. Evans; Thomas R. Mayr; John M. Hollis; Colin D. Brown

1999-01-01

394

Soils - Part 1: The Origin and Development of Soil(How Soil Gets a Life and a Name)  

NSDL National Science Digital Library

 In this lesson, you will gain an understanding of the five soil forming factors and will be able to describe how each influences soil development. You will learn to identify common parent materials, determine the age of a soil, identify the types of native vegetation associated with different soils in Nebraska and define soil horizons.[This lesson, as well as the other nine lessons in the Soils series, is taken from the "Soils Home Study Course," published in 1999 by the University of Nebraska Cooperative Extension.

395

Using atmospheric fallout to date organic horizon layers and quantify metal dynamics during decomposition  

NASA Astrophysics Data System (ADS)

High concentrations of metals in organic matter can inhibit decomposition and limit nutrient availability in ecosystems, but the long-term fate of metals bound to forest litter is poorly understood. Controlled experiments indicate that during the first few years of litter decay, Al, Fe, Pb, and other metals that form stable complexes with organic matter are naturally enriched by several hundred percent as carbon is oxidized. The transformation of fresh litter to humus takes decades, however, such that current datasets describing the accumulation and release of metals in decomposing organic matter are timescale limited. Here we use atmospheric 210Pb to quantify the fate of metals in canopy-derived litter during burial and decay in coniferous forests in New England and Norway where decomposition rates are slow and physical soil mixing is minimal. We measure 210Pb inventories in the O horizon and mineral soil and calculate a 60-630 year timescale for the production of mobile organo-metallic colloids from the decomposition of fresh forest detritus. This production rate is slowest at our highest elevation (˜1000 m) and highest latitude sites (>63°N) where decomposition rates are expected to be low. We calculate soil layer ages by assuming a constant supply of atmospheric 210Pb and find that they are consistent with the distribution of geochemical tracers from weapons fallout, air pollution, and a direct 207Pb application at one site. By quantifying a gradient of organic matter ages with depth in the O horizon, we describe the accumulation and loss of metals in the soil profile as organic matter transforms from fresh litter to humus. While decomposition experiments predict that Al and Fe concentrations increase during the initial few years of decay, we show here that these metals continue to accumulate in humus for decades, and that enrichment occurs at a rate higher than can be explained by quantitative retention during decomposition alone. Acid extractable Al and Fe concentrations are higher in the humus layer of the O horizon than in the mineral soil immediately beneath this layer: it is therefore unlikely that physical soil mixing introduces significant Al and Fe to humus. This continuous enrichment of Al and Fe over time may best be explained by the recent suggestion that metals are mined from deeper horizons and brought into the O horizon via mycorrhizal plants. In sharp contrast to Al and Fe, we find that Mn concentrations in decomposing litter layers decrease exponentially with age, presumably because of leaching or rapid uptake, which may explain the low levels of acid extractable Mn in the mineral soil. This study quantifies how metals are enriched and lost in decomposing organic matter over a longer timescale than previous studies have been able to characterize. We also put new limits on the rate at which metals in litter become mobile organo-metallic complexes that can migrate to deeper soil horizons or surface waters.

Kaste, James M.; Bostick, Benjamin C.; Heimsath, Arjun M.; Steinnes, Eiliv; Friedland, Andrew J.

2011-03-01

396

Statistical analyses of field corrosion data for ductile cast iron pipes buried in sandy marine sediments  

SciTech Connect

Field corrosion studies were conducted on bare, ductile cast iron pipes buried 17 y in sandy marine sediment classified as sandy soil and containing iron bacteria, sulfate-reducing bacteria (SRB), and other bacteria. Chemical and biochemical analyses of the sediment were performed in the laboratory. Correlation between the maximum corrosion depth (P{sub max}) and 21 environmental factors was evaluated by applying a correlation analysis. On that basis, the factors controlling corrosion damage were considered by quantification theory analysis. A corrosion mechanism was presented to explain the corrosion phenomena. The corrosion site had a positive correlation with the anaerobic site, characterized by particularly high levels of water content and ferrous sulfide generated by SRB. Corrosion was classified as graphitic and attributed to formation of extensive tubercles resulting from high activity of iron bacteria in the bicarbonate enriched soil.

Kajiyama, F.; Koyama, Y. [Tokyo Gas Co., Ltd. (Japan). Fundamental Technology Research Lab.

1997-02-01

397

Geomorphic Analysis of Soils  

NSDL National Science Digital Library

Students are taken to a former plantation along a tidal river near Charleston, SC. The students are then shown how to sample and describe soils using an push-auger sampler, similar to those used in industry. After the demonstration, the students are taken to various locations on the plantation, including upland areas, wetlands, former agricultural areas, lowlands, and tidal marshes, to sample and make field descriptions of the various soils encountered. Students describe depths to horizons, soil color using Munsell Color Charts, soil texture, and any other pertinent properties. Students then prepare a formal technical write-up on the soils, their distribution, and how their sampling results compare to published soil data for the area. Designed for a geomorphology course Uses online and/or real-time data

Doyle, Briget

398

A methodology to determine soil moisture movement due to thermal gradients  

Microsoft Academic Search

Moisture and heat migration through the soil mass is an important consideration for the safety of electrical gadgets buried in the soil mass. Continuous passage of current through these gadgets increases their temperature, which may result in redistribution or migration of the moisture in the surrounding soil mass. Excessive changes in the soil moisture may lead to its thermal instability,

S. Krishnaiah; D. N. Singh

2003-01-01

399

Identification of buried structures (aerial surveillance and analysis of buried waste) long-range project plan  

SciTech Connect

This long-range plan presents the plan (i.e., budget, schedule, justification, and plans for technology deployment) for implementation of the Identification of Buried Structures project. Two subcontractors will test and demonstrate their technologies at the Idaho National Engineering Laboratory during October and November 1991, and will analyze their data and submit final reports to EG G Idaho, Inc., by the end of December 1991. By February 21, 1992, EG G Idaho will present a final report to the Department of Energy, assessing the subcontractor's results and recommending further action.

Williams, K.L.

1991-11-01

400

Identification of buried structures (aerial surveillance and analysis of buried waste) long-range project plan  

SciTech Connect

This long-range plan presents the plan (i.e., budget, schedule, justification, and plans for technology deployment) for implementation of the Identification of Buried Structures project. Two subcontractors will test and demonstrate their technologies at the Idaho National Engineering Laboratory during October and November 1991, and will analyze their data and submit final reports to EG&G Idaho, Inc., by the end of December 1991. By February 21, 1992, EG&G Idaho will present a final report to the Department of Energy, assessing the subcontractor`s results and recommending further action.

Williams, K.L.

1991-11-01

401

Mars - Paleostratigraphic restoration of buried surfaces in Tharsis montes  

SciTech Connect

Volcanism in the Tharsis province of Mars occurred in several different areas and was generally continuous without large time intervals between eruptive episodes. Major lava flow units are numerous and extensive, but relatively thin. In many places, impact craters on buried surfaces project above younger flows that overlie them. A new application of crater dating methods has been developed to aid in the identification of these buried surfaces and to determine their lateral extent. The technique is especially adaptable to the Tharsis region where the stratigraphic succession of major flow units has been established by detailed geologic mapping. Knowledge of the overall stratigraphy allows correlations to be made between known and unknown surfaces by comparing their crater frequencies at diameters large enough to insure their recognition on the buried unit. The method has been applied to aid in the restoration of buried rock units and to construct a series of paleostratigraphic maps showing the sequence of major eruptive events in the Tharsis region.

Scott, D.H.; Tanaka, K.L.

1981-01-01

402

Corrosion and Corrosion Prevention in Buried Pipelines and Containers.  

National Technical Information Service (NTIS)

Summaries are presented of papers on the underground corrosion behavior of metals and methods for prevention of corrosion in buried pipes and containers. The summaries included are: corrosion behavior of metallic materials; corrosion behavior of copper an...

1979-01-01

403

Detection of Buried Mines and Unexploded Ordnance (UXO).  

National Technical Information Service (NTIS)

Most military and commercial detectors sense the presence of metal casings or components of buried mines or explosive ordnance; however, this traditional approach to mine and unexploded ordnance (UXO) detection is prone to high false alarm rates. Explosiv...

B. Balko D. Heberlein I. Chappell J. Biddle

2007-01-01

404

Standard KDFOC4 Fallout Calculations for Buried Nuclear Detonations.  

National Technical Information Service (NTIS)

The collateral damage caused by fallout from shallow-buried nuclear devices is of considerable interest. In this paper, we present results for 'standard' calculations using the KDFOC4 fallout computer code. Results are presented for a parametric range of ...

F. Serduke

2001-01-01

405

Charge transfer in buried-channel charge-coupled devices  

Microsoft Academic Search

A detailed numerical simulation of the charge-transfer process in buried-channel CCDs will be presented. The limitations on the device performance due to incomplete free charge transfer, device parameters and clocking waveforms will be discussed.

Yoshiak Daimon; Amr M. Mohsen; Thomas C. McGill

1974-01-01

406

Assessment of soil contamination by the content of heavy metals in the soil profile  

NASA Astrophysics Data System (ADS)

A new soil-ecological definition of the maximal permissible concentration (MPC) of heavy metals in soils is suggested that regulates the sampling in contaminated territories. Instead of the shallow pits usually used for collecting surface samples for soil-hygienic and other investigations, it is proposed to fulfill a detailed analysis along the entire soil profile including not only the determination of the heavy element content in certain horizons but also the soil density in these horizons. For the polyelemental contamination Zc (according to the Saet equation) based on the background (clarke) excess, the established Zc values ranging from 1 to 128, may reach absurd values of 800-900 upon taking into consideration only one surface layer. At the same time, the use of the weighted average content of the metals in the soil profile adjusts the Zc values for the existing natural conditions. Upon aerial impact, the consideration of the heavy metal contents along the soil profile instead of their contents in the surface horizon only leads to a decrease in the indices of the soil contamination degree. Upon the hydrogenic impact, the transition from the heavy metal contents in the surface horizon to their contents in the soil profile gives higher values of the soil contamination.

Vodyanitskii, Yu. N.; Yakovlev, A. S.

2011-03-01

407

A long-term soil leaching column experiment investigating the effect of variable sulphate loads on soil solution and soil drainage chemistry  

Microsoft Academic Search

A series of leaching column experiments were set-up to investigate the effects of increasing and decreasing the sulphate load on the uppermost mineral horizon of an acidified podzolic soil from NE Scotland. The soils showed signs of recovery when the sulphate load was reduced and acidified further when the sulphate load was increased. For the soils in which simulated precipitation

M. E Hodson; S. J Langan

1999-01-01

408

Data fusion for the detection of buried land mines  

SciTech Connect

The authors conducted experiments to demonstrate the enhanced delectability of buried land mines using sensor fusion techniques. Multiple sensors, including imagery, infrared imagery, and ground penetrating radar, have been used to acquire data on a number of buried mines and mine surrogates. The authors present this data along with a discussion of the application of sensor fusion techniques for this particular detection problem. The authors describe the data fusion architecture and discuss some relevant results of these classification methods.

Clark, G.A.; Sengupta, S.K.; Schaich, P.C.; Sherwood, R.J.; Buhl, M.R.; Hernandez, J.E.; Kane, R.J.; Barth, M.J.; Fields, D.J.; Carter, M.R.

1993-10-01

409

Conditioned defensive burying in rats free to escape  

Microsoft Academic Search

Rats shocked once by a stationary, wire-wrapped prod bury it if suitable materials are available. Does this conditioned defensive\\u000a burying occur when rats have the opportunity to flee from the source of aversive stimulation, or is it limited to situations\\u000a such as those in which it had previously been studied—those in which the relatively small test chamber confined each rat

John P. J. Pinel; Dallas Treit; Ferial Ladak; A. J. MacLennan

1980-01-01

410

Uniphase buried-channel charge-coupled devices  

Microsoft Academic Search

Single-electrode uniphase buried-channel CCDs exhibit attractive capabilities such as reduced power consumption, increased density and fabrication yield, and simpler driving circuitry requirements compared to multiple-phase devices. The present paper discusses this type of CCDs and proposes several structures. Preliminary results indicate that the stepped-oxide approach using strongly doped\\/thin lightly doped\\/thick regions for the buried layer is best suited for this

R. M. Barsan

1979-01-01

411

Buried object remote detection technology for law enforcement  

Microsoft Academic Search

A precise airborne temperature-sensing technology to detect buried objects for use by law enforcement is developed. Demonstrations have imaged the sites of buried foundations, walls and trenches; mapped underground waterways and aquifers; and been used to locate underground military objects. The methodology is incorporated in a commercially available, high signal-to-noise, dual-band infrared scanner with real-time, 12-bit digital image processing software

Nancy K. del Grande; Gregory A. Clark; Philip F. Durbin; David J. Fields; Jose E. Hernandez; Robert J. Sherwood

1991-01-01

412

Time Horizon and Social Scale in Communication  

NASA Astrophysics Data System (ADS)

In 2009 our center (CRED) published a first version of The Psychology of Climate Change Communication. In it, we attempted to summarize facts and concepts from psychological research that could help guide communication. While this work focused on climate change, most of the ideas are at least partly applicable for communication about a variety of natural hazards. Of the many examples in this guide, I mention three. Single-action bias is the human tendency to stop considering further actions that might be needed to deal with a given hazard, once a single action has been taken. Another example is the importance of group affiliation in motivating voluntary contributions to joint action. A third concerns the finding that group participation enhances understanding of probabilistic concepts and promotes action in the face of uncertainty. One current research direction, which goes beyond those included in the above publication, focuses on how time horizons arise in the thinking of individuals and groups, and how these time horizons might influence hazard preparedness. On the one hand, individuals sometimes appear impatient, organizations look for immediate results, and officials fail to look beyond the next election cycle. Yet under some laboratory conditions and in some subcultures, a longer time horizon is adopted. We are interested in how time horizon is influenced by group identity and by the very architecture of planning and decision making. Institutional changes, involving long-term contractual relationships among communities, developers, insurers, and governments, could greatly increase resilience in the face of natural hazards. Communication about hazards, in the context of such long-term contractual relationships might look very different from communication that is first initiated by immediate threat. Another new direction concerns the social scale of institutions and of communication about hazards. Traditionally, insurance contracts share risk among a large number of insurees: each contributes a small premium toward a fund that is adequate to cover the large losses that occasionally occur. Participatory processes are needed that extend risk sharing to larger social scales and that reduce adversarial relationships between insurers, insurees, insurance regulators, and governments that intervene or fail to intervene on an ad hoc rather than a contractual basis.

Krantz, D. H.

2010-12-01

413

Black hole thermodynamics from Euclidean horizon constraints.  

PubMed

To explain black hole thermodynamics in quantum gravity, one must introduce constraints to ensure that a black hole is actually present. I show that for a large class of black holes, such "horizon constraints" allow the use of conformal field theory techniques to compute the density of states, reproducing the Bekenstein-Hawking entropy in a nearly model-independent manner. One standard string theory approach to black hole entropy arises as a special case, lending support to the claim that the mechanism may be "universal." I argue that the relevant degrees of freedom are Goldstone-boson-like excitations arising from the weak breaking of symmetry by the constraints. PMID:17678209

Carlip, S

2007-07-10

414

European scientists' proposals for HORIZON 2000+  

NASA Astrophysics Data System (ADS)

This programme, which has been given the name Horizon 2000+, will be presented to the press at 0900h on Monday 17 October 1994 at ESA Headquarters in Paris by Professor Lodewijk Woltjer, who chaired the committee of European scientific community representatives set up to consider the proposals submitted, and Professor Roger Bonnet, ESA's Science Programme Director. Journalists wishing to attend this press breakfast are requested to complete and return the attached form, if possible by fax: (33.1) 42.73.76.90.

1994-10-01

415

New horizons mapping of Europa and Ganymede.  

PubMed

The New Horizons spacecraft observed Jupiter's icy satellites Europa and Ganymede during its flyby in February and March 2007 at visible and infrared wavelengths. Infrared spectral images map H2O ice absorption and hydrated contaminants, bolstering the case for an exogenous source of Europa's "non-ice" surface material and filling large gaps in compositional maps of Ganymede's Jupiter-facing hemisphere. Visual wavelength images of Europa extend knowledge of its global pattern of arcuate troughs and show that its surface scatters light more isotropically than other icy satellites. PMID:17932288

Grundy, W M; Buratti, B J; Cheng, A F; Emery, J P; Lunsford, A; McKinnon, W B; Moore, J M; Newman, S F; Olkin, C B; Reuter, D C; Schenk, P M; Spencer, J R; Stern, S A; Throop, H B; Weaver, H A

2007-10-12

416

Prolate horizons and the Penrose inequality  

SciTech Connect

The Penrose inequality has so far been proven in cases of spherical symmetry and in cases of zero extrinsic curvature. The next simplest case worth exploring would be nonspherical, nonrotating black holes with nonzero extrinsic curvature. Following Karkowski et al.'s construction of prolate black holes, we define initial data on an asymptotically flat spacelike 3-surface with nonzero extrinsic curvature that may be chosen freely. This gives us the freedom to define the location of the apparent horizon such that the Penrose inequality is violated. We show that the dominant energy condition is violated at the poles for all cases considered.

Tippett, Benjamin K. [Department of Mathematics and Statistics, University of New Brunswick, Fredericon, New Brunswick, E3B 5A3 (Canada)

2009-05-15

417

Odor analysis of decomposing buried human remains  

Microsoft Academic Search

This study, conducted at the University of Tennessee's Anthropological Research Facility (ARF), lists and ranks the primary chemical constituents which define the odor of decomposition of human remains as detected at the soil surface of shallow burial sites. Triple sorbent traps were used to collect air samples in the field and revealed eight major classes of chemicals which now contain

Arpad Alexander Vass; Rob R. Smith; Cyril V. Thompson; Michael N. Burnett; Nishan Dulgerian; Brian A. Eckenrode

2008-01-01

418

Main features of anthropogenic inner-urban soils in Szeged, Hungary  

NASA Astrophysics Data System (ADS)

At the beginning of the 21st century, due to the intensive urbanization it is necessary to gather more and more information on altered physical, chemical and biological parameters of urban soils in order to ensure their suitable management and protection for appropriate living conditions. Nowadays, these measures are very relevant since negative environmental effects can modify the soil forming factors in cities. Szeged, the 4th largest city of Hungary, proved to be an ideal sampling area for the research of urban soils since its original surface has been altered by intensive anthropogenic activities. The main objectives of my research are the investigation, description and evaluation of the altered soils in Szeged. For the physical and chemical analysis (humus, nitrogen, carbonate content, heavy metals, pH, artefacts etc.) of soils 124 samples were taken from the horizons of 25 profiles in Szeged and its peripherals (as control samples). The profiles were sampled at sites affected by different extent of artificial infill according to infill maps (1. profiles fully made up of infill; 2. so-called mixed profiles consisting of considerable amount of infill material and buried soil horizons; 3. natural profiles located in the peripherals of the city). With the help of the above-mentioned parameters, the studied soils of Szeged were assigned into the classification system of WRB(2006), which classifies the soils of urban and industrial areas as an individual soil group (under the term Technosols) for the first time. In accordance with the WRB(2006) nomenclature three main soil types can be identified in Szeged with respect to the degree of human influence: profiles slightly influenced, strongly modified, completely altered by human activities. During this poster, we present the peculiarities of typical urban profiles strongly and completely altered by human influence. Most profiles were placed into the group of Technosols due to the considerable transformation of their diagnostic properties (e.g. coverage by artificial objects, intensive compaction, horizontal and vertical variability, abrupt colour and textural changes usually high amount of artefacts, irregular fluctuation of diagnostic properties along the profiles, anthropogenic parent material, high pH and carbonate content, poor humus quality, mainly sand, sandy loam texture etc.). Transformations were best reflected by suffixes such as Ekranic, Urbic, Linic. Among the suffix qualifiers Calcaric, Ruptic, Densic and Arenic were used the most frequently. Furthermore, we found that some of the studied profiles were not situated in the city centre. Consequently, the location of these profiles in the city centre is not necessary since local influences can overwhelm the effect of artificial infill. Considering all the profiles, two of them in city centre can be consider to be the most anthropogenic: profile No. 11 [Ekranic Technosol (Ruptic, Toxic, Endoclayic)] and profile No. 22 [Urbic Technosol (Calcaric, Ruptic, Densic, Arenic)]. It can be claimed that profile No. 11 with "technic hard rock" has the least chance to experience pedogenetic processes since the horizons are covered by thick, surface artificial object, and isolated from the outside world. However, in case of profile No. 22 with dense vegetation and without surface artificial object, the high amount of artefact inhibits pedogenesis.

Puskás, Irén.; Farsang, Andrea

2010-05-01

419

Black hole horizons from within loop quantum gravity  

NASA Astrophysics Data System (ADS)

In general relativity, the fields on a black hole horizon are obtained from those in the bulk by pullback and restriction. Similarly, in quantum gravity, the quantized horizon degrees of freedom should result from restricting, or pulling back, the quantized bulk degrees of freedom. This is not yet fully realized in the—otherwise very successful—quantization of isolated horizons in loop quantum gravity. In this work we outline a setting in which the quantum horizon degrees of freedom are simply components of the quantized bulk degrees of freedom. There is no need to quantize them separately. We present evidence that for a horizon of sphere topology, the resulting horizon theory is remarkably similar to what has been found before.

Sahlmann, Hanno

2011-08-01

420

Decomposition of forest products buried in landfills.  

PubMed

The objective of this study was to investigate the decomposition of selected wood and paper products in landfills. The decomposition of these products under anaerobic landfill conditions results in the generation of biogenic carbon dioxide and methane, while the un-decomposed portion represents a biogenic carbon sink. Information on the decomposition of these municipal waste components is used to estimate national methane emissions inventories, for attribution of carbon storage credits, and to assess the life-cycle greenhouse gas impacts of wood and paper products. Hardwood (HW), softwood (SW), plywood (PW), oriented strand board (OSB), particleboard (PB), medium-density fiberboard (MDF), newsprint (NP), corrugated container (CC) and copy paper (CP) were buried in landfills operated with leachate recirculation, and were excavated after approximately 1.5 and 2.5yr. Samples were analyzed for cellulose (C), hemicellulose (H), lignin (L), volatile solids (VS), and organic carbon (OC). A holocellulose decomposition index (HOD) and carbon storage factor (CSF) were calculated to evaluate the extent of solids decomposition and carbon storage. Samples of OSB made from HW exhibited cellulose plus hemicellulose (C+H) loss of up to 38%, while loss for the other wood types was 0-10% in most samples. The C+H loss was up to 81%, 95% and 96% for NP, CP and CC, respectively. The CSFs for wood and paper samples ranged from 0.34 to 0.47 and 0.02 to 0.27gOCg(-1) dry material, respectively. These results, in general, correlated well with an earlier laboratory-scale study, though NP and CC decomposition measured in this study were higher than previously reported. PMID:23942265

Wang, Xiaoming; Padgett, Jennifer M; Powell, John S; Barlaz, Morton A

2013-08-12

421

SOIL AND LAND CLASSIFICATION IN SWAZILAND  

Microsoft Academic Search

The Swaziland soil classification, originally devised by Murdoch, has been revised to allowits use for the intensive soil surveys now required within the sugar industry. The original set groupings (which are themselves broad units of land potential) and most of the soilserieshavebeenretained, with the addition of new series where required. However, they are now defined using diagnostic horizons from the

M. WORKMAN

422

Status of soil acidification in North America  

Treesearch

Description: Forest soil acidification and depletion of nutrient cations have ... area growth of sugar maple and levels of calcium and magnesium in soil and foliage. ... Mountains in southern California near the west coast, the pH of the A horizon ...

423

Radiation from quantum weakly dynamical horizons in loop quantum gravity.  

PubMed

We provide a statistical mechanical analysis of quantum horizons near equilibrium in the grand canonical ensemble. By matching the description of the nonequilibrium phase in terms of weakly dynamical horizons with a local statistical framework, we implement loop quantum gravity dynamics near the boundary. The resulting radiation process provides a quantum gravity description of the horizon evaporation. For large black holes, the spectrum we derive presents a discrete structure which could be potentially observable. PMID:23031096

Pranzetti, Daniele

2012-07-02

424

Apparent horizons in the quasispherical Szekeres models  

NASA Astrophysics Data System (ADS)

The notion of an apparent horizon (AH) in a collapsing object can be carried over from the Lemaître-Tolman to the quasispherical Szekeres models in three ways: 1. Literally by the definition—the AH is the boundary of the region, in which every bundle of null geodesics has negative expansion scalar. 2. As the locus, at which null lines that are as nearly radial as possible are turned toward decreasing areal radius R. These lines are in general nongeodesic. The name “absolute apparent horizon” (AAH) is proposed for this locus. 3. As the boundary of a region, where null geodesics are turned toward decreasing R. The name “light collapse region” is proposed for this region (which is three-dimensional in every space of constant t); its boundary coincides with the AAH. The AH and AAH coincide in the Lemaître-Tolman models. In the quasispherical Szekeres models, the AH is different from (but not disjoint with) the AAH. Properties of the AAH and light collapse region are investigated, and the relations between the AAH and the AH are illustrated with diagrams using an explicit example of a Szekeres metric. It turns out that an observer who is already within the AH is, for some time, not yet within the AAH. Nevertheless, no light signal can be sent through the AH from the inside. The analogue of the AAH for massive particles is also considered.

Krasi?ski, Andrzej; Bolejko, Krzysztof

2012-06-01

425

Cool horizons lead to information loss  

NASA Astrophysics Data System (ADS)

There are two evidences for information loss during black hole evaporation: (i) a pure state evolves to a mixed state and (ii) the map from the initial state to final state is non-invertible. Any proposed resolution of the information paradox must address both these issues. The firewall argument focuses only on the first and this leads to order one deviations from the Unruh vacuum for maximally entangled black holes. The nature of the argument does not extend to black holes in pure states. It was shown by Avery, Puhm and the author that requiring the initial state to final state map to be invertible mandates structure at the horizon even for pure states. The proof works if black holes can be formed in generic states and in this paper we show that this is indeed the case. We also demonstrate how models proposed by Susskind, Papadodimas et al. and Maldacena et al. end up making the initial to final state map non-invertible and thus make the horizon "cool" at the cost of unitarity.

Chowdhury, Borun D.

2013-10-01

426

Gribov's horizon and the ghost dressing function  

NASA Astrophysics Data System (ADS)

We study a relation recently derived by K. Kondo at zero momentum between the Zwanziger’s horizon function, the ghost dressing function and Kugo’s functions u and w. We agree with this result as far as bare quantities are considered. However, assuming the validity of the horizon gap equation, we argue that the solution w(0)=0 is not acceptable since it would lead to a vanishing renormalized ghost dressing function. On the contrary, when the cutoff goes to infinity, u(0)??, w(0)?-? such that u(0)+w(0)?-1. Furthermore w and u are not multiplicatively renormalizable. Relaxing the gap equation allows w(0)=0 with u(0)?-1. In both cases the bare ghost dressing function, F(0,?), goes logarithmically to infinity at infinite cutoff. We show that, although the lattice results provide bare results not so different from the F(0,?)=3 solution, this is an accident due to the fact that the lattice cutoffs lie in the range 1-3GeV-1. We show that the renormalized ghost dressing function should be finite and nonzero at zero momentum and can be reliably estimated on the lattice up to powers of the lattice spacing; from published data on a 804 lattice at ?=5.7 we obtain FR(0,?=1.5GeV)?2.2.

Boucaud, Ph.; Leroy, J. P.; Le Yaouanc, A.; Micheli, J.; Pène, O.; Rodríguez-Quintero, J.

2009-11-01

427

Gribov's horizon and the ghost dressing function  

SciTech Connect

We study a relation recently derived by K. Kondo at zero momentum between the Zwanziger's horizon function, the ghost dressing function and Kugo's functions u and w. We agree with this result as far as bare quantities are considered. However, assuming the validity of the horizon gap equation, we argue that the solution w(0)=0 is not acceptable since it would lead to a vanishing renormalized ghost dressing function. On the contrary, when the cutoff goes to infinity, u(0){yields}{infinity}, w(0){yields}-{infinity} such that u(0)+w(0){yields}-1. Furthermore w and u are not multiplicatively renormalizable. Relaxing the gap equation allows w(0)=0 with u(0){yields}-1. In both cases the bare ghost dressing function, F(0,{lambda}), goes logarithmically to infinity at infinite cutoff. We show that, although the lattice results provide bare results not so different from the F(0,{lambda})=3 solution, this is an accident due to the fact that the lattice cutoffs lie in the range 1-3 GeV{sup -1}. We show that the renormalized ghost dressing function should be finite and nonzero at zero momentum and can be reliably estimated on the lattice up to powers of the lattice spacing; from published data on a 80{sup 4} lattice at {beta}=5.7 we obtain F{sub R}(0,{mu}=1.5 GeV){approx_equal}2.2.

Boucaud, Ph.; Leroy, J. P.; Le Yaouanc, A.; Micheli, J.; Pene, O. [Laboratoire de Physique Theorique1 Universite de Paris XI, Batiment 210, 91405 Orsay Cedex (France); Rodriguez-Quintero, J. [Dpto. Fisica Aplicada, Fac. Ciencias Experimentales, Universidad de Huelva, 21071 Huelva (Spain)

2009-11-01

428

30 CFR 823.12 - Soil removal and stockpiling.  

Code of Federal Regulations, 2013 CFR

...materials. Where combinations of such soil materials created by mixing have been shown to be equally or more favorable for plant growth than the B horizon, separate handling is not necessary. (d) Stockpiles shall be placed within the permit...

2013-07-01

429

Modeling Storm Water Runoff and Soil Interflow in a Managed ...  

Treesearch

Washington, D.C. ... Interflow (shallow subsurface lateral flow) can short-circuit rainfall infiltration, preventing deep seepage and ... The soil series at the site ( Wagram, Dothan, Fuquay, Ogeechee, and Vaucluse) each have a clay-rich B horizon ...

430

Slicing dependence of nonspherically symmetric quasilocal horizons in Vaidya spacetimes  

NASA Astrophysics Data System (ADS)

It is well known that quasilocal black hole horizons depend on the choice of a time coordinate in a spacetime. This has implications for notions such as the surface of the black hole and also on quasilocal physical quantities such as horizon measures of mass and angular momentum. In this paper, we compare different horizons on nonspherically symmetric slicings of Vaidya spacetimes. The spacetimes we investigate include both accreting and evaporating black holes. For some simple choices of the Vaidya mass function corresponding to collapse of a hollow shell, we compare the area for the numerically found axisymmetric trapping horizons with the area of the spherically symmetric trapping horizon and event horizon. We find that, as expected, both the location and area are dependent on the choice of foliation. However, the area variation is not large, of order 0.017% for a slowly evolving horizon with m?=0.02. We also calculate analytically the difference in area between the spherically symmetric quasilocal horizon and event horizon for a slowly accreting black hole. We find that the difference can be many orders of magnitude larger than the Planck area for sufficiently large black holes.

Nielsen, Alex B.; Jasiulek, Michael; Krishnan, Badri; Schnetter, Erik

2011-06-01

431

Gravitational anomaly and Hawking radiation near a weakly isolated horizon  

NASA Astrophysics Data System (ADS)

Based on the idea of the work by Wilczek and his collaborators, we consider the gravitational anomaly near a weakly isolated horizon. We find that there exists a universal choice of tortoise coordinate for any weakly isolated horizon. Under this coordinate, the leading behavior of a quite arbitrary scalar field near a horizon is a 2-dimensional chiral scalar field. This means we can extend the idea of Wilczek and his collaborators to more general cases and show the relation between gravitational anomaly and Hawking radiation is a universal property of a black hole horizon.

Wu, Xiaoning; Huang, Chao-Guang; Sun, Jia-Rui

2008-06-01

432

Dynamics of diffeomorphism degrees of freedom at a horizon  

SciTech Connect

We define a set of boundary conditions that ensure the presence of a null hypersurface with the essential characteristics of a horizon, using the formalism of weakly isolated horizons as a guide. We then determine the diffeomorphisms that preserve these boundary conditions, and derive a dynamical action for these diffeomorphisms in a neighborhood of the horizon. The action is similar to that of the Liouville theory, and the equation of motion of the gravitational degrees of freedom approaches that of a free two-dimensional conformal field in the near-horizon region.

Chung, Hyeyoun [Jefferson Physical Laboratory, Harvard University, 17 Oxford Street, Cambridge, Massachusetts 02138 (United States)

2011-04-15

433

Temporal horizon: modulation by smoking status and gender  

PubMed Central

Recently, delay discounting has been argued to be conceptually consistent with the notion of temporal horizon (Bickel et al., 2008). Temporal horizon refers to the temporal distance over which behavioral events or objects can influence behavior. Here we examine the results on two putative measures of temporal horizon, future time perspective (FTP) and delay discounting, collected over three separate studies (n = 227), to determine the influence of smoking and gender on temporal horizon. By comparing the results on these temporal horizon measures we address our population of interest: women who smoke. One of the measures of FTP indicates that smoking women have a shorter temporal horizon than their nonsmoking counterparts. Additionally, the story completion measures of FTP are positively correlated with delay discounting. In contrast, results of delay discounting measures showed no difference between smoking women and nonsmoking women, while results of delay discounting measures indicated smoking men have a shorter temporal horizon than non-smoking men. Additionally, the results of the FTP story completion measure indicated that lower third income earners had a shortened temporal horizon compared to upper third income earners. A possible explanation for these results is explored, and the implications of the modulation of temporal horizon by gender and smoking are discussed.

Jones, Bryan A.; Landes, Reid D.; Yi, Richard; Bickel, Warren K.

2009-01-01

434

Soils with complex organic profiles on the Vasyugan Plain  

NASA Astrophysics Data System (ADS)

Soils with intricate patterns of their humus profiles developing in the neutral-calcium landscapes of the southern taiga of Western Siberia under highly dynamic paleogeographic, climatic, and weather conditions are characterized. The specific features of these soils comprise the diverse modern humus horizons along with the relic ones of different preservation rates, shallow leaching of carbonates, and a weak development of the middle-profile soil horizons. Specifying these organo-accumulative soils is substantiated by their high humus content against the geochemical background of the clayey calcareous parent rocks. The conjugated series of soils reflect different stages of the soil evolution (the humus profile degradation, the development of eluvial process, and the increase of contrasts in the acid-base conditions) and the hydromorphic transformation accompanied by the formation of organic horizons making the humus profile more complicated. In accordance with the diagnostic horizons, the position of the soils studied was determined in the Classification and Diagnostics of Soils of Russia. The relic enrichment of the humus horizon is proposed to be used as a specific feature of these soils.

Dyukarev, A. G.; Pologova, N. N.

2011-05-01

435

Soil Carbon and Nitrogen, and Characteristics of Soil Active Layer in Siberian Permafrost Region  

Microsoft Academic Search

\\u000a Permafrost region of Siberia is mostly covered with larch forest or forest tundra. The permafrost-affected soils were generally\\u000a classified as Cambisols (moderately developed soils) on plain topography and Leptosols (shallow and high gravel content soils)\\u000a in mountainous topography (FAO 1993). The latest revision of soil classification systems of both USDA and FAO adopted permafrost\\u000a as a diagnostic horizon, and created

Y. Matsuura; M. Hirobe

436

CROP MANAGEMENT EFFECTS ON WATER INFILTRATION FOR CLAYPAN SOILS  

Technology Transfer Automated Retrieval System (TEKTRAN)

Plant water and nutrient use for claypan soils are restricted by an argillic horizon (clay content > 500 g/kg) that typically occurs 20 to 40 cm below the soil surface. Identifying water infiltration characteristics for claypan soils under different management provides crucial information needed to ...

437

Comparison of groundwater colloids in adjoining soils of Florida flatwoods  

Microsoft Academic Search

Colloids in soil water are a constituent of natural geochemical fluxes and have the potential to facilitate contaminant transport, but few data are available on their composition and concentration. This study addresses how the composition and concentration of groundwater solids relate to hydrological and soil morphological variables of the Florida flatwoods landscape. Groundwater from saturated soil horizons was sampled biweekly

Z. X. Tan; W. G. Harris; L. Q. Ma

2000-01-01

438

Viable and robust system for infrared detection of buried land mines  

NASA Astrophysics Data System (ADS)

An IR mine detection system has been developed which reliably detects buried land miens in certain environmental conditions. The system uses two commercial IR cameras, one using the 3-5 micron band and the other using the 8-12 micron band. The cameras are mounted above a HMMWV and are tilted down to look 2.5 to 7 meters ahead of the vehicle, covering almost a four meter wide swath. Software algorithms are used to de-warp the raw images to remove keystoning and lens curvature effects, producing rectilinear images of the terrain. The mines are observed in the images as cool spots or hot spots on the surface of the soil, with temperatures depending upon the mine type, the recent temperature history of the soil, and the moisture content and soil type. Raw video images are presented which show some of these effects, including when the contrast is so low to be visibly hidden in the background. Filtering algorithms are utilized to perform background identification and removal, producing an equalized image, which enhances the contrast of the buried mines. Statistical order filters are employed that further enhance the mines, with examples again shown. Threshold and object detection algorithms have been developed that autonomously detect mine-like objects in the images without operator intervention. Feature extraction algorithms then search for features that distinguish the mines sought, including such features as size and shape. The objects are classified as a mine or a non-mine and this decision passed on to the registration and hi-level inference detection subsystems of the mine detection platform.

Kilgore, Roger; Swinehart, Steve

1999-08-01

439

Black soils, sediments and brown calcic luvisols: A pedological description of a newly discovered neolithic ring ditch system at Stephansposching, Eastern Bavaria, Germany  

Microsoft Academic Search

Because soils reflect past physical and chemical formation conditions, they are valuable geoarchives, but the knowledge of past soil patterns is restricted. Thus, buried soils of different ages are often used to reconstruct soil development stages. Soils were analyzed at a newly discovered and excavated Neolithic ring ditch system that was constructed some 6700 years ago in east Bavaria, Germany.

Matthias Leopold; Kerstin Hürkamp; Jörg Völkel; Karl Schmotz

2011-01-01