Relevant bibliographies by topics / Soil profiles

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  1. Journal articles
  2. Dissertations / Theses
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  4. Book chapters
  5. Conference papers
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Academic literature on the topic 'Soil profiles'

Author: Grafiati
Published: 4 June 2021
Last updated: 1 August 2024

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Journal articles on the topic "Soil profiles"

1

Salh, Qadri, Zhino Abdalla, Khasraw Rashid, and Shuela Sheikh-Abdullah. "Assessment of Fe, Ni, Zn, Cu, Cr, and Cd Migration in Soil Profiles Affected by Open Dump Leachate in Tanjero area." Journal of Zankoy Sulaimani - Part A 25, no. 2 (December 20, 2023): 12. http://dx.doi.org/10.17656/jzs.10917.

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The properties of an open dump area are important to the application of the elements to the soils and their migrations through soil depth; therefore this study was investigated to evaluate the migration of elements in an open dump area. Soil samples were taken from three soil profiles, one of them was at an open dump site, and the second and third profiles were taken at different distances from the open dump site. In total eighteen soil sample were collected. Some soil physical and chemical properties were determined for each horizon. Total concentrations of Fe, Ni, Zn, Cu, Cr, and Cd were determined in each soil sample. The results indicated that the Fe had the highest value and the Cd had the lowest values in all soil samples. The orders of profiles for the total heavy (Ni, Cd, and Cr) metals were as follows: Profile1 > profile3 > profile 2. The order of profiles for the total heavy (Zn and Cu) metals was as follows: Profile 1 > profile 2 > profile 3. The mean value of total Ni ranged between 9.17 and 11.13, Cd between 0.29 and 0.37, Cr between 2.67 and 3.36, Zn between 6.90 and 17.23, and Cu between 4.90 and 12.52. The highest amount of total Ni, Cd, Cr, Zn, and Cu were observed in open dump area (profile 1) with the mean value (11.13, 0.37, 3.36, 17.23, and 12.52) respectively, compared to the profile 2 and 3. In general, the heavy metals did not show a specific pattern of distribution with depth in the three soil profiles, because there are many factors affecting migration of heavy metals in soil depth. In both profile 2 and 3, some of the heavy metals migrated in soil depth.
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Mad Said, Mohd Jazlan, Adnan Zainorabidin, and Aziman Madun. "Soil Velocity Profile on Soft Soil Using Seismic Refraction." Applied Mechanics and Materials 773-774 (July 2015): 1549–54. http://dx.doi.org/10.4028/www.scientific.net/amm.773-774.1549.

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Soil velocity profile often used as subsurface characterization by using geophysical technic. Seismic refraction is one of geophysical technique to determine primary wave (p-wave) velocity of soil profile. In this paper, seismic refraction technique has been performed on two different types of soft soil (peat soil and RECESS clay) for comparison of its p-wave velocity soil profile. From p-wave velocity soil profile comparison, its show the peat soil has soil velocity range from 211 m/s – 534 m/s at depth of 0 – 4 m while the soft clay show soil velocity range from 248 m/s – 1842 m/s at depth of 0 – 5.5 m. The profiles of peat soils and RECESS clay have been verified using peat samplers and existing borehole data. Both of velocity soil profiles, indicated that peat soil have lower velocity compare with soft clay due to its unique and soft soil characteristics. The difference of p-wave velocity soil profile between peat soil and soft clay are clearly showed both soils have different soil p-wave velocity with different soils characteristics.
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Hidayat, Wahyu, Dyah Tjahyandari Suryaningtyas, and Budi Mulyanto. "Soil fertility based on mineralogical properties to support sustainable agriculture management." SAINS TANAH - Journal of Soil Science and Agroclimatology 21, no. 1 (June 30, 2024): 95. http://dx.doi.org/10.20961/stjssa.v21i1.85502.

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<p>Detailed information on soil mineral composition has been crucial in providing the basis for designing sustainable agricultural practices, as this information offers long-term insights into natural soil fertility. This research aimed to further investigate the characteristics of soil mineral composition as a basis for managing soil fertility. Three soil profiles representing three different parent materials have been examined in the field, and soil samples have been collected for laboratory analysis. Profile 1 originates from the Raung Volcano Rock Formation (Qhvr). Profile 2 originates from the Sukamade Formation (Toms). Profile 3 originates from Puger Formation (Tmp). The presence of Mount Raung volcanic influence results in distinct soil characteristics in Profiles 2 and 3 compared to typical sedimentary and karst rock soils. The sand fraction minerals in all three profiles are predominantly composed of opaque minerals, followed by rock fragments, ferromagnesian mineral series (olivine, augite, hypersthene, and hornblende), plagioclase minerals (anorthite, biotite, and labradorite), iron concretions, epidote, and tourmaline. The clay fraction minerals in all three profiles consist of illite, kaolinite, and quartz. The minerals illite and ferromagnesian groups in all three profiles play a significant role in increasing the availability of potassium, calcium, and magnesium nutrients, thereby reducing the need for fertilizers for these elements. The soils in all three profiles naturally possess good fertility; however, designing a sustainable agricultural system requires consideration of the morphology, landform, and climate of all three profiles.</p>
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O'Brien, Bernard John. "The Use of Natural and Anthropogenic 14C to Investigate the Dynamics of Soil Organic Carbon." Radiocarbon 28, no. 2A (1986): 358–62. http://dx.doi.org/10.1017/s0033822200007463.

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Radiocarbon has been measured in two soil profiles, one of which has been covered by a building since 1956. A comparison of the Δ14C values in horizons of each profile gives an estimate of the total input of atom bomb 14C into the soil profile. From the Δ14C and carbon density profile data, the carbon input rates, respiration rates, and diffusivity are calculated. The lack of vegetation on one soil affects the mobility and the respiration rate of the soil carbon in that soil. The data from this soil profile are also used to check the assumption, used in previous analyses, that there is a uniform distribution of ‘old’ carbon down the soil profile. The input rate, turnover time, and diffusivity parameters determined from the Δ14C profiles in these soils are compared with other published data on pasture and forest soils.
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Babayeva, A., S. Adygozelova, S. Mikailova, K. Abdullayeva, and A. Mamedova. "Factors Forming Soil Combinations and Comparative Geographical Approaches to the Study of Soil Cover Structure." Bulletin of Science and Practice, no. 8 (August 15, 2023): 27–38. http://dx.doi.org/10.33619/2414-2948/93/03.

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The comparative geographical approach to the study of soils consists in the parallel study of soils and soil formation factors at various points and in the analysis of their relationships. Compilation of profiles can be carried out in the office (if there is sufficient cartographic material) or on the basis of special field studies. Often both of these methods are combined: profiles of smaller scales are compiled in the office, and larger scales — on the basis of special field studies. Soil formation factors were also applied to these profiles (first of all, the relief that determined the profile line), while usually only those factors were applied that had a decisive influence on the differentiation of the soil cover, caused the emergence of soil combinations.
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Skvortsova, E. B., K. N. Abrosimov, and K. A. Romanenko. "CHANGES IN MICROMORPHOMETRIC PARAMETERS OF VOIDS ALONG THE PROFILE OF ZONAL SOILS IN EUROPEAN RUSSIA." Dokuchaev Soil Bulletin, no. 78 (May 1, 2015): 42–58. http://dx.doi.org/10.19047/0136-1694-2015-78-42-58.

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The soils are distinguished by the presence and the profile distribution pattern of such pedogenic parameters as the organic matter content, available pedofeatures, structural state of the soil mass, etc. They differ in the organization of the pore space throughout the soil profile as well. Under discussion are results of computer micromorphometric analysis of fine macropores d = 0.2-2.0 mm in thin sections of vertical orientation from samples taken in genetic horizons of podzolic, soddy podzolic, gray forest soils and chernozems at the territory of European Russia. The profile changes in voids were analyzed using the most informative morphometric parameters such as the total area of the studied voids in thin sections, the content of fissure-like voids and those of vertical and/or horizontal orientation. The soil types under study showed differences in profile distribution of the above parameters. By analogy with the profile of carbonates, salts, organic matter it is proposed to recognize diagnostic profiles of the pore space represented as a system of voids in genetic horizons of the soil profile. Empiric profiles of the pore space reveal a great diversity. The most complicated organization of the pore space is inherent to soddy podzolic soils, the most simple “smoothed” profiles are characteristic of typical chernozems. The expert qualitative typization showed that the eluvial-illuvial and accumulative-eluvial-illuvial types are dominant among the studied empiric profiles of the pore space (42 and 30% respectively), what is explained by prevailing texture-differentiated soils. On the other hand, it makes possible to use the profile of the pore space as a diagnostic parameter of soils and soil formation processes.
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Yu, Dandan, Feilong Hu, Kun Zhang, Li Liu, and Danfeng Li. "Available water capacity and organic carbon storage profiles in soils developed from dark brown soil to boggy soil in Changbai Mountains, China." Soil and Water Research 16, No. 1 (December 11, 2020): 11–21. http://dx.doi.org/10.17221/150/2019-swr.

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The available water capacity (AWC) is the most commonly used parameter for quantifying the amount of soil water that is readily available to plants. Specific AWC and soil organic carbon storage (SOCS) profiles are consequences of the soil development process. Understanding the distributions of AWC and SOCS in soil profiles is crucial for modelling the coupling between carbon and water cycle processes, and for predicting the consequences of global change. In this study, we determined the variations in the AWC and SOCS from the surface to a depth of 100 cm in soils developed from dark brown soil, skeletal dark brown soil, meadow dark brown soil, white starched dark brown soil, meadow soil, and boggy soil in the Changbai Mountains area of China. The AWC and SOCS profiles were calculated for each main soil group/subgroup using only the readily available variables for the soil texture and organic matter with the soil water characteristic equations. The results showed the following. (1) The AWC and SOCS decreased initially and then increased, before decreasing again in soils developed from dark brown soil to boggy soil, where the maximum SOCS occurred in the white starched dark brown soil, and the maximum AWC in the dark brown soil. (2) The SOCS was decreased by deforestation and concomitant soil erosion, but the negative impact of this decrease in the SOCS in the Changbai Mountains area was not caused completely by reductions in AWC. (3) In the soil development process from dark brown soil to boggy soil in response to deforestation, the AWC distribution differed in the profile and even among individual layers, whereas the SOCS was mainly present in the upper layer.
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Durak, Alper, and Mehmet Erdem Aydın. "Yeşilırmak Nehir Teraslarında Toprakların Oluşumu ve Sınıflandırılması." Turkish Journal of Agriculture - Food Science and Technology 2, no. 2 (February 27, 2014): 98. http://dx.doi.org/10.24925/turjaf.v2i2.98-105.97.

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In this study, the soils of which parent material is alluvial and formed Yeşilırmak river terraces were investigated. For this purposes four different profiles were excavated in the study area. Then twenty-seven soil samples were taken from horizons of four profiles and their physical and chemical analyses were done for soil taxonomy research. Profile of Kumocagi and Cakil were classified in subgroup as Typic Ustipsamments, Havaalanı and Mera profiles were classified Typic Haplustolls and Typic Argiustolls subgroups respectively. The pH values of soils varied between 7.38-8.41. These soils can be classified as low and highly basic. Most of the soil series had an irregular pH distribution in the profile. The range of carbonate content of the soils was 0.8-25.4%. Although carbonate content of soils showed a very wide range, majority of them can be classified as highly calcareous. In most of soils carbonate content was distributed irregulary in the profile. Organic matter content were between 0.14-6.11% in the soils. Although organic matter contents of the soils changed in a wide range most of them had low organic matter content. Organic matter content was over 4% in the surface horizon of only two profiles. Research result showed that, alluvial parent material, particle size, topograpy and time have different effect on investigation soils.
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P. GURUMURTHY and T. SREELATHA. "CHEMICAL COMPOSITION AND PEDOGENESIS OF SOILS OF AGRICULTURAL COLLEGE FARM, NAIRA, ANDHRA PRADESH." Journal of Research ANGRAU 51, no. 3 (October 5, 2023): 14–23. http://dx.doi.org/10.58537/jorangrau.2023.51.3.02.

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The study on elemental composition and pedogenesis of soils of Agricultural College farm, Naira of Srikakulam district was carried-out during 2021. The soils were developed from granite-gneiss parent material. Total silica (SiO2) content of soils ranged from 50.5 to 74.6 percentage. Silica content in general decreased with soil depth, while sesquioxides (R2O3), alumina (Al2O3), iron oxide (Fe2O3), CaO, K2O, Na2O, MnO were found increasing with depth. High silica/ sesquioxide ratio of soils indicated siliceous nature of soils. The aluminum oxide content of the profiles varied from 15.80% to 26.25%. Highest value was reported in lowland profile, whereas, the lowest value was recorded in rainfed upland profile. Iron oxide content varied from 5.04% to 8.50%. Iron oxide content showed slight variation within profiles. Among the other oxides, CaO > MgO > K2O > Na2O was of the order as the soils were developed under semi-arid climate, wherein, basic cations have accumulated in these soil profiles due to limited leaching. The molar concentration of silica (SiO2) ranged from 0.841 to 1.24 moles, and molar concentration of sesquioxide ranged from 0.191 to 0.313 moles. The molar ratio of SiO2 / R2O3 varied from 2.68 to 6.51 in different soil profiles. The SiO2 / Al2O3 ratio varied from 3.33 to 8.02. These wider molar ratios indicated salacious nature of parent material and due to dominance of silica among chemical fractions. Midland (P3) and lowland (P4) soil profiles showed silt/clay ratio of less than 0.45 and upland profiles showed more than 0.45 indicating relatively advanced weathering in mid and lowland profiles while it was moderate weathering in upland profiles. The Weathering Index of Parker (WIP) values of the soils of study area ranged between 2.8 and 32.4. The lower WIP values (2.8 to 8.1) were associated with rainfed uplands and higher values of 14.7- 32.4 with irrigated low lands. The PIA values ranged from 67 to 97 tend to decrease with the depth in all profiles. The profiles examined have the CIA values varied from 66 to 95 indicating high to intense weathering. The CIA values decreased with depth in all the profiles. The surface horizons of P1 and P2 soil profiles were classified as moderately weathered. On the other hand, all subsurface horizons of these two profiles were highly weathered. However, in profiles P3 and P4 the CIA values ranged between 68 to 90 indicating that these soils were highly weathered. CIW values closely followed the trend of CIA values. The bases/R2O3 values of all profiles ranged from 0.061 to 0.608 and found increased with soil depth in all the profiles. Relatively higher values of bases/R2O3 were found in P4 (low lands) indicating base rich character. Middle land and lowland black soil profiles showed silt/clay ratio of less than 0.45 and upland profiles showed morethan 0.45 indicating relatively advanced weathering in mid and lowland profiles while moderate weathering in upland profiles.
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CICŞA, Avram, Gheorghe Marian TUDORAN, Maria BOROEANU, Alexandru C. DOBRE, and Gheorghe SPÂRCHEZ. "Influence of Soil Genesis Factors on Gurghiu Mountain Forest Soils’ Physical and Chemical Properties." Series II: Forestry • Wood Industry • Agricultural Food Engineering 14(63), no. 2 (December 22, 2021): 1–14. http://dx.doi.org/10.31926/but.fwiafe.2021.14.63.2.1.

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This research aimed to determine the values of chemical properties and the relationships between the main pedoecological factors that characterize the soils in the Gurghiu Mountains. The mapping surveys were carried out on an area of 4,647.36 ha located in the mixed mountain forest sites (FM2) (1,000–1,400 m altitude). The area was stratified into homogeneous site units in terms of climate, hydricity, and trophicity. At the level of the elementary site units, 35 main soil profiles and 46 control profiles were placed. The number of profiles was determined statistically to ensure an error of no more than 10%. Soil samples collected from the main profiles were analyzed in the laboratory. Soil’s properties values decreased on the soil’s profile (humus content from 15 to 2%, nitrogen from 1.1 to 0.5%, sum of exchangeable hydrogen from 20 to 9 me/100 g soil, and total cationic exchange capacity from 38 to 20 me/100 g soil), except the pH and the base saturation degree (the pH increased on profile from 4.5 to 6, and the base saturation degree from 40 to 70%). The soil properties, except for moisture, were significantly affected by altitude, and decreased when the altitude increased. Soil trophicity can be characterized by a soil index, the values of which were between 17 and 42 for the analyzed soils. These values indicated soil-specific trophicity levels from oligotrophic to eutrophic.
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Dissertations / Theses on the topic "Soil profiles"

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Jones, Edward. "Proximal sensing in soil profiles." Thesis, The University of Sydney, 2017. http://hdl.handle.net/2123/18722.

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Objective and quantitative soil information is crucial for pedological investigations and to inform diverse decision making processes. New techniques are required so that soil information can be ascertained in a timely manner to support sampling at finer spatial and temporal resolutions. Currently, no single technique can provide information on all of the properties of interest. This research investigated the conjoint use of visible near-infrared diffuse reflectance spectroscopy (VisNIR) and portable X-ray fluorescence spectroscopy (pXRF) for the in situ investigation of soil properties, profile variability and description. Fifteen soil pits across New South Wales, Australia, were selected for their diverse representation of soil properties. Sampling at these sites involved scanning three vertical with sensor readings taken at 2.5 cm intervals to a depth of 1 m within each transect. Soils were described by traditional pit description techniques and horizon based sampling was conducted to characterise the soil in terms of mineral composition, OC, TC, TN, CEC, EC, pH and PSA. A data fusion approach involving model averaging, and a mass balance was implemented to characterise the mineral composition of soils, including phyllosilicates sesquioxides, carbonate, gypsum, quartz and feldspars. Results were validated against X-ray diffraction analysis. To explore the predictive capability of scans taken in situ, existing spectral libraries were used to calibrate VisNIR and pXRF models and identify the best use of proximal sensor data to maximise soil information gain. As not all properties of interest have detectable spectral activity by either VisNIR or pXRF, a spectral soil inference system (SPEC-SINFERS) to augment the number of predicted properties. This system involved the propagation of sensor and model uncertainties through one hundred independent simulations for each calculation, and allowed the integration of both regression models and machine learning techniques.
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Eaton, Frank Edward. "Generation of predetermined soil profiles in a soil bin." Diss., The University of Arizona, 2001. http://hdl.handle.net/10150/290268.

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The soil preparation in soil bins must be capable of generating a number of soil density profiles varying from uniform to heavily compacted layers lying below more friable soil. A subsurface rotating rod firmed the soil beneath the rod and repeated passes produced desired profiles. Retrofitting the existing instrumentation with virtual instrumentation methods resulted in measurements that were more precise and improved repeatability. A Wheatstone bridge force transducer measured Cone Index pressure as a function of soil penetration depth. Soil surface elevation and implement depths were located with ratiometric linear transducers. Speed and distance were measured with an optical encoder. Prime mover hydraulic oil temperatures and pressures were gauged with current loop sensors. Three Null Hypotheses were tested: a horizontal subsurface rotating rod will not cause an increase in soil cone index; repeated operation of the horizontal rotating rod will not result in increased soil cone indexes; and soil water content is not relevant to the resultant compaction level. The first two Null Hypotheses were rejected at the 5% level in the overall case although not in each case while the third Null Hypotheses was rejected at the 5% level in all cases.
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Wickremesinghe, Damika Sampath. "Statistical characterization of soil profiles using in situ tests." Thesis, University of British Columbia, 1989. http://hdl.handle.net/2429/29319.

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Several statistical procedures that would enhance the site characterization capabilities of insitu test data with special emphasis on the cone penetrometer test have been proposed and presented. Two methods to identify different soil layers from a profile have been described. One of these procedures is based on the effects of the individual parameters, namely, cone bearing, sleeve friction and pore pressure, while the other method employs a multivariate scheme of analysis, which has the capability of handling all three or any two parameters, simultaneously. The advantages of these statistical methods over the conventional methods of soil layer identification, have also been highlighted. Critical levels of the values of the Intraclass Correlation coefficient and the D statistic have been proposed for the identification of layer boundaries as primary or secondary for both sand and clay type soils. Methods of trend analysis have been proposed while the complications arising from the presence of correlations have been discussed. The role played by methods of statistical filtering and smoothing, in the identification of trends, have also been illustrated. Statistical procedures have been proposed, for the purpose of verification of non-stationarity or stationarity, in the event it cannot be determined from a visual inspection. The need for the consideration of geotechnical data as random has been emphasized, together with applications of random field theory in the determination of exceedance probabilities of given threshold values over spatial averages of a soil layer. A computationally more convenient method for the determination of the scale of fluctuation has been proposed while emphasizing its importance in several areas of applications, with respect to the cone penetration test. Time Series methods have been employed in order to model the stationary component of soil profiles and also have been extended to obtain the measurement noise of different test methods. A comparison of the measurement noise of different insitu testing devices, obtained by the time series method has been compared to a procedure based solely on the autocorrelation function of the data, resulting in a good agreement. The relatively low value of measurement noise obtained for the cone penetration test confirms its superiority over other insitu testing methods like the field vane test which gave fairly high estimates of the measurement noise. A two dimensional interpolation procedure considering the correlation between data points has been recommended. This procedure which uses the autocorrelation function, has been applied to a set of cone penetrometer test data and the results of which have been compared with the actual profile at that location. The reasonable comparison of the predicted with the actual, clearly indicate the need for the consideration of correlations if they do exist, in interpolating geotechnical data in two or three dimensions. IBM - PC compatible interactive micro computer programs have been developed in order to perform most of the techniques proposed in the thesis. These programs cater to any type of data format and have several inbuilt options available to the user. Detailed user manuals for these programs are also available.
Applied Science, Faculty of
Civil Engineering, Department of
Graduate
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Ketteringham, Wayne Stuart. "Transient flow of water in saturated-unsaturated soil profiles." Master's thesis, University of Cape Town, 1990. http://hdl.handle.net/11427/8296.

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Includes bibliography.
In this thesis tile transient flow of water, during tile drainage process in saturated-unsaturated soil profiles, was studied. Drainage experiments were performed on two different soil profiles. The first experiment undertaken was tile drainage of a vertical column of sand. This experiment was performed on two sands of differing grain size and grading. The second experiment undertaken was the drainage towards a well from a wedge of sand (cake slice) using yet a different coarse sand.
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Lorz, C. "Ein substratorientiertes Boden-Evolutions-Konzept für geschichtete Bodenprofile : Genese und Eigenschaften von lithologisch diskontinuierlichen Böden /." Berlin : Gebrüder Borntraeger, 2008. http://d-nb.info/987000470/04.

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Timmenga, Hubert J. "The transport of mineral and organic matter into the soil profile by Lumbricus rubellus Hoffmeister." Thesis, University of British Columbia, 1987. http://hdl.handle.net/2429/27551.

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The biology and ecology of the earthworm Lumbricus rubellus Hoffmeister, 1843, and its effects on the turn-over of organic matter and soil are not well known. To gather this information, the ingestion and egestion rates were measured using a litterbag technique and the transport of organic matter was quantified with a newly developed method, using soil columns to which ¹⁴C labelled plant material was added. The feeding habits of the worm were positively influenced by temperature in wet soils (> -15m of water) and were negatively influenced in dry soil (< -15 m of water). The total egestion rate changed from 0.3 g.g⁻¹.day⁻¹ at 5 °C to 1.0 g.g⁻¹. day⁻¹ at 20° C in moist soil (- 5 m of water). The egestion rate at medium range temperatures, 10 and 15° C, was less affected by drought stress than at 5 and 20 °C. The egestion rate of carbon was a more stable parameter than the total egestion rate, and ranged from approximately 20 mg.g⁻¹.day⁻¹ at 5 °C, to 50 mg.g⁻¹.day⁻¹ at 20 °C. The moisture and temperature effects were apparent in the Q₁₀ of the total egestion rate and of the egestion rate of carbon. The Q₁₀ ranged from 1.66 in wet soils to 3.27 in dry soils in the 5-15 °C interval and from 1.98 to 0.32 in the 10-20 °C range. For the egestion rate of carbon, the Q₁₀ ranged from 1.92 to 3.21 and from 1.28 to 0.47, respectively. The body water content of the worm varied considerably with the soil water potential, and reached a maximum level of 5.5 kg.kg⁻¹ (dwt) between -15 metres of water and -30 metres of water. When under drought stress, worms stopped ingesting large quantities of soil, switched to a diet high in organic matter and lowered their activity. In the ¹⁴C column experiment, the total cast production was significantly related to depth. L. rubellus produced 15 % of the cast on the surface of the soil, 46 % in the 0-5 cm layer, 22 % in the 5-10 cm layer and 16 % in the 10-15 cm layer. Independent calculations from a) the uptake of ¹⁴C labelled carbon in earthworms, b) removal of litter from the surface and c) ¹⁴C label recovered from cast, showed that the worms ingested 78-82 % of the offered organic matter as shoot litter and 18-22 % as root litter. ¹⁴C originating from shoot and root litter was recovered in casts throughout the profile, indicating that the worms mixed food from all layers. The total egestion rate found in the column experiment was 5.2 times higher than was found in the litterbag technique under comparable conditions (2.34 vs 0.45 g.g⁻¹.day⁻¹). The egestion rate of carbon was similar in both techniques (37.1 vs. 46.1 mg.g⁻¹.day⁻¹, 10 °C). In preliminary litterbag trials, it was found that L. rubellus egested 15.5 mg.g⁻¹.day⁻¹ of carbon (5 °C) for each of four food types offered. The 5 °C temperature trial of the litterbag technique, showed a similar amount of carbon egested. It was concluded that the worm needed a constant amount of carbon to provide nutrients and energy, of which a part or all may originate from ingested microorganisms. Based on the distribution of cast in the profile and the feeding strategies of L. rubellus, it was concluded that this earthworm cannot be classified as an epigeic worm. A new strategy class was proposed: eurygeic worms, earthworms living in the litter-soil interface, mixing organic matter into the profile and mineral soil into the litter layer. Based on the literature and results from the present study, a computer model was developed to simulate the longterm effects of earthworms on an agricultural soil system. Simulations of the mixing of soil and organic matter in a limited-till agricultural system, showed that earthworms negatively affected the accumulation rate of surface litter and positively affected the organic matter content of the mineral soil. The model can be used to predict the trends in organic matter in soils, important in soil conservation, mine reclamation and reforestation.
Land and Food Systems, Faculty of
Graduate
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7

Jafarzadeh, Aliasghar. "Experimental studies of gypsum migration and deposition in soil profiles." Thesis, Imperial College London, 1991. http://hdl.handle.net/10044/1/46842.

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Henderson, Rachel A. "Partitioning Soil CO2 Efflux through Vertical Profiles of Manipulated Forests in MOFEP." University of Toledo / OhioLINK, 2007. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1177701393.

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Schaap, James Cornelis. "Nitrogen fertilization and tree species effect on the soil microbial communities and consequences for soil carbon." Thesis, University of Canterbury. School of Biological Sciences, 2011. http://hdl.handle.net/10092/6582.

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In the face of ever increasing atmospheric CO₂ a better understanding of soil properties and processes and the effect of management practices, such as the application of nitrogen fertilizer is of importance and could potentially improve our ability to sustainably manage forestry systems. With that in mind this study was conducted in order to investigate the effects of tree species and fertilization on soil carbon and the soil microbial community. To this end, soil from fertilized and unfertilized plots at Berwick forest, under stands of Pinus radiata and Sequoia sempervirens at Hanmer and under six different tree species at Holt forest was sampled. Two glasshouse pot trials were established using soil collected from the Hanmer and Berwick forest sites and seedlings of Pinus radiata, Sequoia sempervirens, and Eucalyptus nitens were grown. Soil properties were determined from both the field sites and pot trials including soil organic matter, carbon, nitrogen, and microbial biomass by chloroform fumigation extraction. Biolog ecoplates were used to determine the relative differences in diversity based on substrate utilization patterns of the soil microbial communities in soil sampled from the glasshouse pot trials. Soil microbial biomass carbon, nitrogen and the ratio of microbial biomass carbon:nitrogen differed significantly between Pinus radiata and the other tree species sampled at Holt forest. Significant effects of fertilization and tree species on soil carbon and microbial biomass were observed in both pot trials. Soil carbon differed significantly between Eucalyptus nitens and both Pinus radiata and Sequoia sempervirens in the first pot trial and relative to both, E. nitens contributed significantly more carbon. No significant effect of either fertilization or tree species on the catabolic diversity of the soil microbial community in both glasshouse pot trials was observed. The results demonstrated the effects that fertilization and tree species can have. Particularly notable was the short-time period in which tree species effects became apparent coupled with the absence of any aboveground inputs to the soil.
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He, Qingping. "Interpretation of fallout radionuclide profiles in sediments from lake and floodplain environments." Thesis, University of Exeter, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.358000.

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Books on the topic "Soil profiles"

1

Remmelzwaal, A. Botswana soil database: Guidelines for soil profile description. Gaborone: Food and Agriculture Organization of the United Nations, 1988.

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Daniels, Raymond Bryant. Soil systems in North Carolina. Raleigh, N.C: North Carolina State University, Soil Science Dept., 1999.

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Food and Agriculture Organization of the United Nations., ed. Guidelines for soil description. 4th ed. Rome: Food and Agriculture Organization of the United Nations, 2006.

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Mitsuchi, Masanori. Outline of soils of the Northeast Plateau, Thailand: Their characteristics and constraints. Khon Kaen, Thailand: Agricultural Development Research Center in Northeast Thailand, 1986.

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Mbuvi, J. P. Explanations and profile description to reconnaissance soil survey of the upper Ewaso Ng'iro basin (Laikipia East and slopes west to north of Mount Kenya). [Nanyuki, Kenya]: Laikipia Research Programme, Natural Resource Monitoring, Modelling, and Management, 1994.

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G, Milne J. D., ed. Soil description handbook. Lincoln, N.Z: Manaaki Whenua Press, 1995.

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Luis, Mejía Vallejo, Ecuador. Dirección de Areas Naturales y Vida Silvestre., Proyecto Plan Maestro para la Protección de la Biodiversidad Mediante el Fortalecimiento del Sistema Nacional de Areas Protegidas (Ecuador), and Proyecto INEFAN-GEF para la Protección de la Biodiversidad., eds. Diagnóstico regional del recurso suelo: Geología, geomorfología, suelos : estudio del uso potencial del suelo en áreas especiales Parque Nacional Yasuní. [Quito?]: Plan Maestro para la Protección de la Biodiversidad Mediante el Fortalecimiento del Sistema Nacional de Areas Protegidas, 1998.

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P, Lof, Van Baren J, International Soil Reference and Information Centre., Food and Agriculture Organization of the United Nations., and Unesco, eds. Soils of the world. Amsterdam, The Netherlands: Elsevier Science Publishers, 1987.

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Hewitt, A. E. Soil properties for plant growth: A guide to recognising soil attributes relevant to plant growth and plant selection. Lincoln, N.Z: Manaaki Whenua Press, 2004.

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Tew, Ronald K. Soil survey--Desert Experimental Range, Utah. Ogden, UT: Intermountain Research Station, 1997.

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Book chapters on the topic "Soil profiles"

1

Holliday, Vance T., Leslie D. McFadden, E. Arthur Bettis, and Peter W. Birkeland. "Soil Survey and Soil-Geomorphology." In Profiles in the History of the U.S. Soil Survey, 233–74. Ames, Iowa, USA: Iowa State Press, 2008. http://dx.doi.org/10.1002/9780470376959.ch9.

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Chesworth, Ward, Marta Camps Arbestain, Felipe Macías, Otto Spaargaren, Otto Spaargaren, Y. Mualem, H. J. Morel‐Seytoux, et al. "Classification of soils: World Reference Base (WRB) soil profiles." In Encyclopedia of Soil Science, 122. Dordrecht: Springer Netherlands, 2008. http://dx.doi.org/10.1007/978-1-4020-3995-9_105.

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Watanabe, Makiko, Nobuo Sakagami, and Kiminori Tonosaki. "Dating of Sclerotia Grains in Andosol Profiles." In Progress in Soil Science, 119–37. Singapore: Springer Singapore, 2021. http://dx.doi.org/10.1007/978-981-33-4252-1_7.

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Andrews, D. F., and A. M. Herzberg. "Particle Size Distribution of Soil Profiles." In Springer Series in Statistics, 119–22. New York, NY: Springer New York, 1985. http://dx.doi.org/10.1007/978-1-4612-5098-2_17.

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Duncan, D. W., and R. J. Oshima. "1,2-Dibromoethane (EDB) in Two Soil Profiles." In ACS Symposium Series, 282–93. Washington, DC: American Chemical Society, 1986. http://dx.doi.org/10.1021/bk-1986-0315.ch014.

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Levin, Maxine J. "Opening Opportunities: Women in Soil Science and the Soil Survey." In Profiles in the History of the U.S. Soil Survey, 149–68. Ames, Iowa, USA: Iowa State Press, 2008. http://dx.doi.org/10.1002/9780470376959.ch5.

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Ali Maroof, M., Danial Rezazadeh Eidgahee, and Ahmad Mahboubi. "Particle Morphology Effect on the Soil Pore Structure." In Lecture Notes in Civil Engineering, 1–10. Singapore: Springer Singapore, 2022. http://dx.doi.org/10.1007/978-981-19-1260-3_1.

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AbstractThe soil fabric can be expressed as a network model. Granular media voids connectivity and constriction size distribution may lead to movement of air, fluids, and solids in the soil, and therefore affect the chemical, physical and mechanical properties of soils. Understanding the soil voids areas and their interconnection might be helpful in understanding different phenomena such as transport in porous media, water retention, fluid flow in the soil, soil contamination, internal erosion, suffusion, and filtration. In addition, specifying the soil voids interconnectivity can help researchers and practical engineers to provide the best rehabilitation and remediation approaches. The pore network was investigated in the current study, assuming the soil particles to be similar to discrete spheres and particles with different shapes. Also, based on the modelling techniques, the profiles of pore connectivity and constriction size distribution were assessed.
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Nichols, Joe D. "Memoirs of a Soil Correlator." In Profiles in the History of the U.S. Soil Survey, 101–48. Ames, Iowa, USA: Iowa State Press, 2008. http://dx.doi.org/10.1002/9780470376959.ch4.

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Arriaga, Francisco J., Birl Lowery, Dalvan J. Reinert, and Kevin McSweeney. "Cone Penetrometers as a Tool for Distinguishing Soil Profiles and Mapping Soil Erosion." In Progress in Soil Science, 401–10. Cham: Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-28295-4_25.

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Miller, D. E. "Water Retention and Flow in Layered Soil Profiles." In SSSA Special Publications, 107–17. Madison, WI, USA: Soil Science Society of America, 2015. http://dx.doi.org/10.2136/sssaspecpub5.c6.

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Conference papers on the topic "Soil profiles"

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JL Eweg, PWL Lyne, and CN Bezuidenhout. "Measuring Soil Pressure Distributions in Undisturbed Soil Profiles." In 2006 Portland, Oregon, July 9-12, 2006. St. Joseph, MI: American Society of Agricultural and Biological Engineers, 2006. http://dx.doi.org/10.13031/2013.20614.

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Spirina, V. Z., L. V. Khotskova, and E. A. Zharikova. "PROPERTIES AND ELEMENT COMPOSITION OF SOILS OF THE DENDROLOGICAL TERRITORY OF THE SIBERIAN BOTANICAL GARDEN." In Prirodopol'zovanie i ohrana prirody: Ohrana pamjatnikov prirody, biologicheskogo i landshaftnogo raznoobrazija Tomskogo Priob'ja i drugih regionov Rossii. Izdatel'stvo Tomskogo gosudarstvennogo universiteta, 2020. http://dx.doi.org/10.17223/978-5-94621-954-9-2020-55.

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The properties, content and profile distribution of macroelements in the soils of the dendrological territory of the Siberian Botanical Garden were studied. The nature of the distribution of chemical elements in soil profiles is revealed depending on the intensity of sod, podzolic and glue soil formation processes.
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Mayne, Paul W., and Mark Styler. "Soil Liquefaction Screening Using CPT Yield Stress Profiles." In Geotechnical Earthquake Engineering and Soil Dynamics V. Reston, VA: American Society of Civil Engineers, 2018. http://dx.doi.org/10.1061/9780784481455.056.

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Sarikin Samari, Labib, Zhongqi Cheng, Vargas Olga, Kaitlin McLaughlin, Kohinoor Begum, Seidemann David, Salvado Engel-Dimauro, Peter Groffman, Richard K. Shaw, and Elena Timchenko. "SOIL PROFILES IN BIOSWALE: IMPLICATIONS ON SOIL DEVELOPMENT AND BIOSWALE MANAGEMENT." In Northeastern Section - 57th Annual Meeting - 2022. Geological Society of America, 2022. http://dx.doi.org/10.1130/abs/2022ne-375302.

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Голодная, О. М., and Е. А. Жарикова. "FEATURES OF TEXURE OF SOILS OF THE KHANKAISKIY NATURE RESERVE." In Геосистемы Северо-Восточной Азии. Crossref, 2021. http://dx.doi.org/10.35735/tig.2021.41.82.013.

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Изучение гранулометрического состава почв Ханкайского заповедника показало, что профили почв представляют собой многослойные спектры различного литологического сложения. Сложность почвенных профилей по гранулометрическому составу определяется степенью проявления поемного и аллювиального процессов, литологическими особенностями почвообразующего материала. По типу сложения выделено несколько литологических групп. Темно-гумусовые глеевые, аллювиальные луговые глеевые почвы и буроземы глееватые отличаются резкой дифференциацией профиля по гранулометрическому составу на верхнюю легкую и нижнюю глинистую толщу. Для этих почв отмечено наибольшее содержание фракций физической глины и ила по всему почвенному профилю. Буроземы типичные и аллювиальные луговые глееватые, вышедшие из зоны затопления, характеризуются литологически однородным легким составом. В этих почвах выявлено высокое содержание фракций мелкого песка. The soil profiles the Khankaiskiy Nature Reserve represent multilayer spectra of various lithological addition. The complexity of soil profiles in terms of particle-size distribution is determined by the degree of manifestation of soil and alluvial processes, lithological features of soil-forming material. Several lithological groups are distinguished by the type of texture. Dark humus gley, alluvial meadow gley soils and burozem gleyic shrouds are distinguished by a sharp differentiation of the profile by granulometric composition into an upper light and lower clay thickness. The largest content of fractions of physical clay and silt was noted throughout the profiles for these soils. Burozem typical and alluvial meadow gleyic soils that have emerged from the flood zone characterize this with a lithologically homogeneous light composition. A high content of fine sand fractions was revealed in these soils.
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Michaels, P. "Establishing Confidence in Surface Wave Determined Soil Profiles." In Georisk 2011. Reston, VA: American Society of Civil Engineers, 2011. http://dx.doi.org/10.1061/41183(418)88.

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Sandu, C., A. Sandu, and L. Li. "Stochastic Modeling of Terrain Profiles and Soil Parameters." In 2005 SAE Commercial Vehicle Engineering Conference. 400 Commonwealth Drive, Warrendale, PA, United States: SAE International, 2005. http://dx.doi.org/10.4271/2005-01-3559.

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Sullivan, W. Griffin, Tim Cost, and Isaac L. Howard. "Measurement of Cementitiously Stabilized Soil Slurry Thermal Profiles." In GeoCongress 2012. Reston, VA: American Society of Civil Engineers, 2012. http://dx.doi.org/10.1061/9780784412121.099.

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Totani, F., and V. Toemi. "SDMT VS profiles in heterogeneous granular soil deposits." In 7th International Conference on Geotechnical and Geophysical Site Characterization. CIMNE, 2024. http://dx.doi.org/10.23967/isc.2024.312.

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Fernandez, J. Alfredo, Glenn J. Rix, and Savannah Gowdy. "Inversion Algorithm to Evaluate Velocity Profiles from Downhole Seismic Tests." In Geotechnical Earthquake Engineering and Soil Dynamics Congress IV. Reston, VA: American Society of Civil Engineers, 2008. http://dx.doi.org/10.1061/40975(318)60.

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Reports on the topic "Soil profiles"

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Watt, P. M. Preliminary Report on Uncontaminated Soil Profiles, Los Alamos National Laboratory, New Mexico. Office of Scientific and Technical Information (OSTI), January 1995. http://dx.doi.org/10.2172/763032.

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Klassen, R. A., I. Girard, and C. Gregoire. Trace-metal concentrations and mercury speciation in two soil profiles, Thunder Bay, Ontario. Natural Resources Canada/ESS/Scientific and Technical Publishing Services, 2002. http://dx.doi.org/10.4095/213206.

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Furey, John, Austin Davis, and Jennifer Seiter-Moser. Natural language indexing for pedoinformatics. Engineer Research and Development Center (U.S.), September 2021. http://dx.doi.org/10.21079/11681/41960.

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The multiple schema for the classification of soils rely on differing criteria but the major soil science systems, including the United States Department of Agriculture (USDA) and the international harmonized World Reference Base for Soil Resources soil classification systems, are primarily based on inferred pedogenesis. Largely these classifications are compiled from individual observations of soil characteristics within soil profiles, and the vast majority of this pedologic information is contained in nonquantitative text descriptions. We present initial text mining analyses of parsed text in the digitally available USDA soil taxonomy documentation and the Soil Survey Geographic database. Previous research has shown that latent information structure can be extracted from scientific literature using Natural Language Processing techniques, and we show that this latent information can be used to expedite query performance by using syntactic elements and part-of-speech tags as indices. Technical vocabulary often poses a text mining challenge due to the rarity of its diction in the broader context. We introduce an extension to the common English vocabulary that allows for nearly-complete indexing of USDA Soil Series Descriptions.
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Ziegler, Nancy, Nicholas Webb, Adrian Chappell, and Sandra LeGrand. Scale invariance of albedo-based wind friction velocity. Engineer Research and Development Center (U.S.), May 2021. http://dx.doi.org/10.21079/11681/40499.

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Obtaining reliable estimates of aerodynamic roughness is necessary to interpret and accurately predict aeolian sediment transport dynamics. However, inherent uncertainties in field measurements and models of surface aerodynamic properties continue to undermine aeolian research, monitoring, and dust modeling. A new relation between aerodynamic shelter and land surface shadow has been established at the wind tunnel scale, enabling the potential for estimates of wind erosion and dust emission to be obtained across scales from albedo data. Here, we compare estimates of wind friction velocity (u*) derived from traditional methods (wind speed profiles) with those derived from the albedo model at two separate scales using bare soil patch (via net radiometers) and landscape (via MODIS 500 m) datasets. Results show that profile-derived estimates of u* are highly variable in anisotropic surface roughness due to changes in wind direction and fetch. Wind speed profiles poorly estimate soil surface (bed) wind friction velocities necessary for aeolian sediment transport research and modeling. Albedo-based estimates of u* at both scales have small variability because the estimate is integrated over a defined, fixed area and resolves the partition of wind momentum be-tween roughness elements and the soil surface. We demonstrate that the wind tunnel-based calibration of albedo for predicting wind friction velocities at the soil surface (us*) is applicable across scales. The albedo-based approach enables consistent and reliable drag partition correction across scales for model and field estimates of us* necessary for wind erosion and dust emission modeling.
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Klassen, R. A. Soil profiles in naturally metal-rich terrains of eastern Canada: physical properties and geochemical data. Natural Resources Canada/ESS/Scientific and Technical Publishing Services, 2003. http://dx.doi.org/10.4095/214638.

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Haneberg, William C. Use of seismic reflection profiles to characterize soil deformation associated with earth fissures and groundwater withdrawal near Deming, New Mexico. New Mexico Bureau of Geology and Mineral Resources, 1990. http://dx.doi.org/10.58799/ofr-367.

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Harris, Kathleen, and Travis Dahl. Technical assessment of the Old, Mississippi, Atchafalaya, and Red (OMAR) Rivers : HEC-RAS BSTEM analysis of the Atchafalaya River. Engineer Research and Development Center (U.S.), August 2022. http://dx.doi.org/10.21079/11681/45174.

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This report documents the bank erosion modeling performed under Task 6 (HEC-RAS Sediment Modeling) of the Old, Mississippi, Atchafalaya, and Red (OMAR) Rivers System Technical Assessment. The objectives of the bank erosion modeling effort were to compare the relative impact various flow scenarios might have on bank retreat on a stretch of the Atchafalaya River between Simmesport, LA, and the Whiskey Bay Pilot Channel. The effort included compilation of field and soil boring data, selection of bank retreat sites, creation of representative soil profiles for the reach, calibration of soil parameters to measured retreat rates, and modeling bank retreat and volume of material eroded under various flow scenarios. This modeling effort was intended for scenario comparison and should not be used as a prediction of exact rates of bank erosion. The study found that varying the amount of flow entering the Atchafalaya River from the Mississippi River could increase dramatically or significantly reduce the extent of bank erosion, relative to the current management scenario.
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Banin, Amos, Joseph Stucki, and Joel Kostka. Redox Processes in Soils Irrigated with Reclaimed Sewage Effluents: Field Cycles and Basic Mechanism. United States Department of Agriculture, July 2004. http://dx.doi.org/10.32747/2004.7695870.bard.

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The overall objectives of the project were: (a) To measure and study in situ the effect of irrigation with reclaimed sewage effluents on redox processes and related chemical dynamics in soil profiles of agricultural fields. (b) To study under controlled conditions the kinetics and equilibrium states of selected processes that affect redox conditions in field soils or that are effected by them. Specifically, these include the effects on heavy metals sorption and desorption, and the effect on pesticide degradation. On the basis of the initial results from the field study, increased effort was devoted to clarifying and quantifying the effects of plants and water regime on the soil's redox potential while the study of heavy metals sorption was limited. The use of reclaimed sewage effluents as agricultural irrigation water is increasing at a significant rate. The relatively high levels of suspended and, especially, dissolved organic matter and nitrogen in effluents may affect the redox regime in field soils irrigated with them. In turn, the changes in redox regime may affect, among other parameters, the organic matter and nitrogen dynamics of the root zone and trace organic decomposition processes. Detailed data of the redox potential regime in field plots is lacking, and the detailed mechanisms of its control are obscure and not quantified. The study established the feasibility of long-term, non-disturbing monitoring of redox potential regime in field soils. This may enable to manage soil redox under conditions of continued inputs of wastewater. The importance of controlling the degree of wastewater treatment, particularly of adding ultrafiltration steps and/or tertiary treatment, may be assessed based on these and similar results. Low redox potential was measured in a field site (Site A, KibutzGivat Brenner), that has been irrigated with effluents for 30 years and was used for 15 years for continuous commercial sod production. A permanently reduced horizon (Time weighted averaged pe= 0.33±3.0) was found in this site at the 15 cm depth throughout the measurement period of 10 months. A drastic cultivation intervention, involving prolonged drying and deep plowing operations may be required to reclaim such soils. Site B, characterized by a loamy texture, irrigated with tap water for about 20 years was oxidized (Time weighted average pe=8.1±1.0) throughout the measurement period. Iron in the solid phases of the Givat Brenner soils is chemically-reduced by irrigation. Reduced Fe in these soils causes a change in reactivity toward the pesticide oxamyl, which has been determined to be both cytotoxic and genotoxic to mammalian cells. Reaction of oxamyl with reduced-Fe clay minerals dramatically decreases its cytotoxicity and genotoxicity to mammalian cells. Some other pesticides are affected in the same manner, whereas others are affected in the opposite direction (become more cyto- and genotoxic). Iron-reducing bacteria (FeRB) are abundant in the Givat Brenner soils. FeRB are capable of coupling the oxidation of small molecular weight carbon compounds (fermentation products) to the respiration of iron under anoxic conditions, such as those that occur under flooded soil conditions. FeRB from these soils utilize a variety of Fe forms, including Fe-containing clay minerals, as the sole electron acceptor. Daily cycles of the soil redox potential were discovered and documented in controlled-conditions lysimeter experiments. In the oxic range (pe=12-8) soil redox potential cycling is attributed to the effect of the daily temperature cycle on the equilibrium constant of the oxygenation reaction of H⁺ to form H₂O, and is observed under both effluent and freshwater irrigation. The presence of plants affects considerably the redox potential regime of soils. Redox potential cycling coupled to the irrigation cycles is observed when the soil becomes anoxic and the redox potential is controlled by the Fe(III)/Fe(II) redox couple. This is particularly seen when plants are grown. Re-oxidation of the soil after soil drying at the end of an irrigation cycle is affected to some degree by the water quality. Surprisingly, the results suggest that under certain conditions recovery is less pronounced in the freshwater irrigated soils.
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Wang, Yao, Jeehee Lim, Rodrigo Salgado, Monica Prezzi, and Jeremy Hunter. Pile Stability Analysis in Soft or Loose Soils: Guidance on Foundation Design Assumptions with Respect to Loose or Soft Soil Effects on Pile Lateral Capacity and Stability. Purdue University, 2022. http://dx.doi.org/10.5703/1288284317387.

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The design of laterally loaded piles is often done in practice using the p-y method with API p-y curves representing the behavior of soil at discretized points along the pile length. To account for pile-soil-pile interaction in pile groups, AASHTO (2020) proposes the use of p-multipliers to modify the p-y curves. In this research, we explored, in depth, the design of lateral loaded piles and pile groups using both the Finite Element (FE) method and the p-y method to determine under what conditions pile stability problems were likely to occur. The analyses considered a wide range of design scenarios, including pile diameters ranging from 0.36 m (14.17 inches) to 1.0 m (39.37 inches), pile lengths ranging from 10 m (32.81 ft) to 20 m (65.62 ft), uniform and multilayered soil profiles containing weak soil layers of loose sand or normally consolidated (NC) clay, lateral load eccentricity ranging from 0 m to 10 m (32.81 ft), combined axial and lateral loads, three different pile group configurations (1×5, 2×5, and 3×5), pile spacings ranging from 3 to 5 times the pile diameter, two different load directions (“strong” direction and “weak” direction), and two different pile cap types (free-standing and soil-supported pile caps). Based on the FEA results, we proposed new p-y curve equations for clay and sand. We also examined the behavior of the individual piles in the pile groups and found that the moment applied to the pile cap is partly transferred to the individual piles as moments, which is contrary to the assumption often made that moments are fully absorbed by axial loads on the group piles. This weakens the response of the piles to lateral loading because a smaller lateral pressure is required to produce a given deflection when moments are transferred to the head of the piles as moments. When the p-y method is used without consideration of the transferred moments, unconservative designs result. Based on the FEA results, we proposed both a new set of p-multipliers and a new method to use when moment distribution between piles is not known, using pile efficiency instead to calculate the total capacity of pile groups.
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Crowley, David E., Dror Minz, and Yitzhak Hadar. Shaping Plant Beneficial Rhizosphere Communities. United States Department of Agriculture, July 2013. http://dx.doi.org/10.32747/2013.7594387.bard.

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PGPR bacteria include taxonomically diverse bacterial species that function for improving plant mineral nutrition, stress tolerance, and disease suppression. A number of PGPR are being developed and commercialized as soil and seed inoculants, but to date, their interactions with resident bacterial populations are still poorly understood, and-almost nothing is known about the effects of soil management practices on their population size and activities. To this end, the original objectives of this research project were: 1) To examine microbial community interactions with plant-growth-promoting rhizobacteria (PGPR) and their plant hosts. 2) To explore the factors that affect PGPR population size and activity on plant root surfaces. In our original proposal, we initially prqposed the use oflow-resolution methods mainly involving the use of PCR-DGGE and PLFA profiles of community structure. However, early in the project we recognized that the methods for studying soil microbial communities were undergoing an exponential leap forward to much more high resolution methods using high-throughput sequencing. The application of these methods for studies on rhizosphere ecology thus became a central theme in these research project. Other related research by the US team focused on identifying PGPR bacterial strains and examining their effective population si~es that are required to enhance plant growth and on developing a simulation model that examines the process of root colonization. As summarized in the following report, we characterized the rhizosphere microbiome of four host plant species to determine the impact of the host (host signature effect) on resident versus active communities. Results of our studies showed a distinct plant host specific signature among wheat, maize, tomato and cucumber, based on the following three parameters: (I) each plant promoted the activity of a unique suite of soil bacterial populations; (2) significant variations were observed in the number and the degree of dominance of active populations; and (3)the level of contribution of active (rRNA-based) populations to the resident (DNA-based) community profiles. In the rhizoplane of all four plants a significant reduction of diversity was observed, relative to the bulk soil. Moreover, an increase in DNA-RNA correspondence indicated higher representation of active bacterial populations in the residing rhizoplane community. This research demonstrates that the host plant determines the bacterial community composition in its immediate vicinity, especially with respect to the active populations. Based on the studies from the US team, we suggest that the effective population size PGPR should be maintained at approximately 105 cells per gram of rhizosphere soil in the zone of elongation to obtain plant growth promotion effects, but emphasize that it is critical to also consider differences in the activity based on DNA-RNA correspondence. The results ofthis research provide fundamental new insight into the composition ofthe bacterial communities associated with plant roots, and the factors that affect their abundance and activity on root surfaces. Virtually all PGPR are multifunctional and may be expected to have diverse levels of activity with respect to production of plant growth hormones (regulation of root growth and architecture), suppression of stress ethylene (increased tolerance to drought and salinity), production of siderophores and antibiotics (disease suppression), and solubilization of phosphorus. The application of transcriptome methods pioneered in our research will ultimately lead to better understanding of how management practices such as use of compost and soil inoculants can be used to improve plant yields, stress tolerance, and disease resistance. As we look to the future, the use of metagenomic techniques combined with quantitative methods including microarrays, and quantitative peR methods that target specific genes should allow us to better classify, monitor, and manage the plant rhizosphere to improve crop yields in agricultural ecosystems. In addition, expression of several genes in rhizospheres of both cucumber and whet roots were identified, including mostly housekeeping genes. Denitrification, chemotaxis and motility genes were preferentially expressed in wheat while in cucumber roots bacterial genes involved in catalase, a large set of polysaccharide degradation and assimilatory sulfate reduction genes were preferentially expressed.
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