Test of possible standard samples for soil physical analyses

2020 ◽  
Author(s):  
Aurore Degré ◽  
Alexandre Pomes-Bordedebat ◽  
Imène Belazereg
Keyword(s):  
Soil Sample ◽  
Chemical Analyses ◽  
Soil Physics ◽  
Standard Samples ◽  
Retention Curve ◽  
Undisturbed Samples ◽  
Measurement Devices ◽  
Structured Soil ◽  
Physics Labs ◽  
Reference Samples

<p>As they mostly deal with undisturbed samples, soil hydrophysics analyses often present variability in their results. No one can deny that soil, and particularly structured soil, is a very complex and challenging media to describe. But it remains that the lab measurements themselves deserve attention. To what extent are they reproducible? To what extent different labs following the same protocol do they provide the same results for a given soil sample? Is this uncertainty quantifiable? Is there a way to standardize or harmonize the analyses? And of course, to what extent does it really matter when it comes to produce reliable information about i.e. drought consequences?</p><p>When most of the labs related to chemical analyses can rely on ring tests to improve their capacity, soil physics labs can’t. Building reference samples that could fit into classical measurement devices is one of the options that could allow to run ring tests in soil physics measurements.</p><p>The poster will present an attempt to develop reference samples in view to measure the wet end of the retention curve.</p>

Chemical Analyses of Canadian Reference Samples: SY-2 and SY-3

1974 ◽  
Vol 7 (8-9) ◽  
pp. 621-626 ◽  
Author(s):  
N. W. Tetley ◽  
A. Turek
Keyword(s):  
Chemical Analyses ◽  
Reference Samples

scholarly journals Samples of concrete of small sizes

2019 ◽  
Vol 91 ◽  
pp. 02043
Author(s):  
Andrew Varlamov ◽  
Sergey Tverskoi ◽  
Vadim Gavrilov
Keyword(s):  
Reinforced Concrete ◽  
Strain State ◽  
Concrete Structures ◽  
Small Samples ◽  
Reinforced Concrete Structures ◽  
Standard Samples ◽  
Stress Strain ◽  
Strength And Deformation ◽  
Loss Of Strength ◽  
Reference Samples

The article analyzes the sizes of concrete samples. We revealed a possibility to reduce sizes of samples. We simultaneously carried out tests of standard and small (25x25x100 mm) concrete samples. Small samples were obtained by cutting standard samples. In the course of study, the density, strength, and deformation of standard and small specimens were measured. The results are presented in tables and graphs. The strength of small samples was lower than the strength of reference samples. We identified loss of strength of the samples when cutting concrete. The average characteristics of deformation of concrete remained. Small samples are recommended for use in assessing the stress-strain state of reinforced concrete structures.

scholarly journals Physical-hydraulic soil attributes in an integrated production system with different “paricá” forest component arrangements

2018 ◽  
Vol 53 (3) ◽  
pp. 351-360 ◽  
Author(s):  
Wellington de Azambuja Magalhães ◽  
Onã da Silva Freddi ◽  
Anderson Lange ◽  
Flávio Jesus Wruck ◽  
Wininton Mendes da Silva ◽  
...  
Keyword(s):  
Production System ◽  
Water Retention ◽  
Water Retention Curve ◽  
Structural Quality ◽  
Soil Water Retention Curve ◽  
Soil Water Retention ◽  
Retention Curve ◽  
Integrated Production ◽  
Soil Penetration Resistance ◽  
Undisturbed Samples

Abstract: The objective of this work was to compare the structural quality and water retention curve of a Haplustox under single, double, and triple “paricá” (Ochroma pyramidale) lines in an integrated production system at 50 months of implantation. Soil was collected from five sampling points considering the distances from the tree lines. Undisturbed samples were collected from the 0.00-0.10 and 0.10-0.20-m layers in order to assess porosity, density, soil penetration resistance, soil water retention curve, and the “S” index. The forest arrangement based on three paricá lines promoted better soil physical conditions than the system using single lines. The main changes were recorded in the 0.10-0.20-m layer, with increased microporosity and decreased cryptoporosity and resistance to penetration. The arrangements using single and double paricá lines result in higher volume of available water and greater soil compaction.

scholarly journals Um panorama das propriedades físicas e químicas de substratos utilizados em horticultura no sul do Brasil

2015 ◽  
Vol 21 (3) ◽  
pp. 299 ◽  
Author(s):  
Gilmar Schafer ◽  
Paulo Vitor Dutra de Souza ◽  
Claudimar Sidnei Fior
Keyword(s):  
Electrical Conductivity ◽  
Total Porosity ◽  
Chemical Characteristic ◽  
Physical Characteristics ◽  
Water Retention Curve ◽  
Chemical Analyses ◽  
Retention Curve ◽  
Commercial Laboratory ◽  
Wide Range ◽  
Physical And Chemical

The cultivation in greenhouse and containers culminated with the necessity to use substrates with formulations as well as distinguished chemical and physical characteristics, the last ones assuming a key role in cultivation of horticultural plants. The aim of this study is to present results of physical and chemical analyses of substrates forwarded to an commercial laboratory (Laboratório de Substratos para Plantas - UFRGS) for the last three years, aiming to establishing a panorama of the substrates area and comparing them with reference values cited in the literature. In this period were performed 307 physical and 479 chemical analyses, which were the basis for this study. Physical analyses performed were the density in dry basis and the water retention curve (total porosity, air space, available water and remaining water). Chemical analyses were the electrical conductivity (EC) and the pH. The main results concerning physical characteristics, demonstrate that the substrates present wide range of density in dry basis and may be used for different sized containers; however most substrates analyzed is out of ideal range for the other physical characteristics of the substrate. For the chemical characteristic the substrates in cultivation in southern Brazil are mostly alkaline and the electrical conductivity of the substrates in cultivation is very diverse, with considerable number of samples above the recommended.

Evaluating Indirectly the X-Ray Tube Spectra on the Basis of the Fundamental Parameter Method in Wavelength-Dispersive X-Ray Spectrometry

1993 ◽  
Vol 37 ◽  
pp. 689-696 ◽  
Author(s):  
I. Szalóki ◽  
B. Magyar
Keyword(s):  
Parameter Method ◽  
Fundamental Parameter ◽  
Standard Samples ◽  
Efficiency Function ◽  
Simultaneous Application ◽  
X Ray ◽  
Calibration Methods ◽  
The Relationship ◽  
Fundamental Parameter Method ◽  
Reference Samples

Several calibration methods and empirical formulae have been developed so far for analyzing materials quantitatively in XRF spectrometry. Many of them require reference samples to determine the relationship between the characteristic intensities of the elements and their concentrations. In order to eliminate empirical and semiempirical procedures, the fundamental parameter method (FPM) has been developed, which is one of the most helpful evaluating tools in quantitative XRF analysis. Some interpretations of this approach have the advantage that no standard samples are needed. The simultaneous application of FPM and polychromatic excitation demand an exact mathematical description of the primary spectral distribution as well as the efficiency function of the detector system.

scholarly journals Laboratory assay of aluminium transport through intact soil sample under controlled conditions

2010 ◽  
Vol 5 (No. 2) ◽  
pp. 69-74 ◽  
Author(s):  
M. Batysta ◽  
L. Borůvka ◽  
O. Drábek ◽  
V. Tejnecký ◽  
O. Šebek
Keyword(s):  
Soil Sample ◽  
European Beech ◽  
Beech Forest ◽  
Al Content ◽  
Undisturbed Samples ◽  
Aluminium Speciation ◽  
Fagus Sylvatica L ◽  
Acid Rainfall ◽  
Intact Soil ◽  
Different Soils

Aluminium (Al) mobilisation in the forest soils is a serious problem due to the soil acidification. The rate and magnitude of leaching of Al and other elements and compounds from soils can be examined by means of percolation experiments. Aluminium elutriation was studied under laboratory conditions using undisturbed samples of forest topsoil from the Paličník area in the Jizera Mountains (Czech Republic), which originated under two different vegetation covers: European beech (Fagus sylvatica L.) and Norway spruce (Picea abies (L.) Karst). Ponding infiltration was performed using three subsequently applied solutions. KCl solution was used to simulate the soil solution. Solutions with sulphates and nitrates addition (of two different pH values) were used to simulate acid rainfall. Passing liquid phase was analysed with respect to Al content and aluminium speciation. Differences were found in Al content and transport between different soils under spruce and beech covers. The soil sample under the spruce forest (SF sample) had a higher initial Al content than the soil sample under the beech forest (BF sample). As a result, the aluminium leaching from the spruce soil sample and the final content of water-extractable Al in the soil (Al content after the leaching experiment) were higher compared to the beech soil sample. This suggests that Al mobility and potential toxicity in the beech forest are grater than those in the spruce monoculture when studied in the acidification endangered areas.

scholarly journals Dependence of the water retention curve of snow on snow characteristics

2012 ◽  
Vol 53 (61) ◽  
pp. 6-12 ◽  
Author(s):  
Satoru Yamaguchi ◽  
Kunio Watanabe ◽  
Takafumi Katsushima ◽  
Atsushi Sato ◽  
Toshiro Kumakura
Keyword(s):  
Grain Size ◽  
Snow Cover ◽  
Water Retention ◽  
Water Movement ◽  
Column Experiment ◽  
Water Retention Curve ◽  
Dry Density ◽  
Soil Physics ◽  
Retention Curve ◽  
Physics Model

AbstractThe water retention curve (WRC), which shows the relationship between the volumetric liquid water content,θv, and suction,h, is a fundamental part of the characterization of hydraulic properties. Therefore, the formulation of the WRC as a function of snow characteristics is essential for establishing a model of water movement through the snow cover. In this study, we measured the WRC of several snow samples, which had different characteristics (grain size, bulk dry density and grain type), using a gravity drainage column experiment and then analysed these data using the Van Genuchten soil physics model (VG model). The shape of the WRC depended strongly on both the sample grain size,d, and bulk dry density,ρ. Therefore, we introduced the parameterρ/dto model the WRC of snow. The relationships between the parametersαandnof the VG model andρ/dchange with grain type. For melt forms,α, which is related to the inverse value of the air-entry suction, increases quickly asρ/ddecreases, whereasn, which is related to the gradient ofθvvsh, increases withρ/d. Conversely, neither of these parameters of the VG model for rounded grains showed obvious dependence onρ/d. These results suggest that water movement through snow cover can be modelled using grain size, bulk dry density and grain type based on the soil physics model.

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