MORPHOLOGY AND GENESIS OF A CHERNOZEMIC TO PODZOLIC SEQUENCE OF SOIL PROFILES IN SASKATCHEWAN

1964 ◽  
Vol 44 (1) ◽  
pp. 88-99 ◽  
Author(s):  
R. J. St. Arnaud ◽  
E. P. Whiteside
Keyword(s):  
Particle Size ◽  
Particle Size Distribution ◽  
Iron Content ◽  
Clay Fraction ◽  
Glacial Till ◽  
Morphological Properties ◽  
Soil Profiles ◽  
Complex Particle ◽  
Fine Clay ◽  
Dominant Cation

Chemical, physical, and micropedological studies were made of Orthic Black, Orthic Dark Grey, Dark Grey Wooded, and Orthic Grey Wooded profiles developed from relatively uniform glacial till material. The general gradation of morphological properties observed for the Black to the Grey Wooded soils is reflected in the thickness of the Ah horizons and of the sola, the development of Ae and textural B horizons, and in the structure and microfabrics of the soil horizons.All four soils are highly base-saturated, calcium being the dominant cation on the exchange complex. Particle size distribution has been affected by both translocation of clay as well as by physical breakdown of coarse fractions particularly within surface horizons. Iron translocation within all four profiles appears to be closely associated with clay movement. The uniform iron content of the fine clay fraction indicates that iron may occur as an integral part of the clay structures and that the clays have undergone little alteration as a result of weathering.

PRE-EMERGENCE HERBICIDE APPLICATION IN CORN CROP

1970 ◽  
pp. 22-28 ◽  
Author(s):  
М. V. Kashukoev ◽  
М. М. Khutsinova ◽  
Zh. О. Kanukova
Keyword(s):  
Particle Size ◽  
Particle Size Distribution ◽  
Size Distribution ◽  
Clay Fraction ◽  
Exchange Reactions ◽  
Herbicide Application ◽  
Physical Clay ◽  
Warm Weather ◽  
Fine Clay ◽  
Environmental Requirements

Presents the results of a study of the effectiveness of herbicides from different chemical classes for pre-emergence control of weeds in maize crops. Investigations were carried out in 2014–2016 in Cherek-Kolos LLC, Urvansky District, Kabardino-Balkaria Republic. The time of studies was distinguished by favourable moisture: the level of fallen September precipitation varied by year: in 2014 – 48 mm, 2015 – 24.3 mm, in 2016 – 51.4 mm and fairly warm weather. The conditions complied with the environmental requirements established for corn. According to the particle-size distribution, the soil of the pilot site is light clay over the whole profile with the content of “physical clay” 51.8 ... 58.9%. Among the fractions of particle-size distribution dominates large dust (30.4-35.8%) and silt (23.6-29.7%), whose portion in physical clay near 51%. The accumulation of the silt fraction (< 0.001 mm) is clearly traced in the upper horizons of the soil profile, that is, silting occurs in the upper horizon, which is determined by the indicator of removal – accumulation, the coefficient of which in the chernozem typical residual meadow is equal to 121.6. The clay fraction is an active part of the soil, it is a colloidal and precolloidal mass consisting of fine clay minerals, hydrophilic and capable of equivalent exchange reactions with the liquid phase. In pre-emergence control, the maximum suppression of perennial dicotyledonous weeds of 82.9-100% is achieved using the herbicides Anaconda, CE (1.6 l / ha) and Adengo, KS (0.5 l / ha). The effectiveness in suppressing perennial cereal weeds when using the herbicide Trophy 90, EC (2.5 l / ha) is 91.0%. Efficiency in the fight against gumaem with the use of the herbicide Lyumaks, SC (4.0 l / ha) is 83%. The grain yield of corn for pre-emergence use of the herbicides Anaconda, CE (1.6 l / ha), Trophy 90, CE (2.5 l / ha), Lyumaks, SC (4.0 l / ha) increases by 29-47% .

scholarly journals Blend of natural waxes as a matrix for aroma encapsulation

2017 ◽  
Vol 15 (2) ◽  
pp. 103-111
Author(s):  
Jelena Milanovic ◽  
Gordana Ilic-Sevic ◽  
Marijana Gavrilovic ◽  
Milutin Milosavljevic ◽  
Branko Bugarski
Keyword(s):  
Particle Size ◽  
Particle Size Distribution ◽  
Size Distribution ◽  
Elevated Temperatures ◽  
Thermal Characteristics ◽  
Feed Additives ◽  
Morphological Properties ◽  
Particle Size Range ◽  
Carnauba Wax ◽  
Potential Applications

In this study, the possibility of using a blend of natural waxes (bees and carnauba) for encapsulation of some aroma compounds was investigated. Melt dispersion/melt solidification technique was applied for microbeads production. Since one of the most important characteristics of the particles are the size and shape, particle size distribution as well as morphological properties are tested. Thermal characteristics are also examined as significant properties for thermal behavior at elevated temperatures, important for application of encapsulated particles in food production processes. Different contents of the carnauba wax in the mixture with beeswax are investigated, from 10% to 50% (w/w). Since one of the potential applications of the encapsulated aroma is in feed additives production, the targeted particle size range was under 300 ?m to be suitable for handling and mixing with other powder substances. According to the obtained results, a higher carnauba wax content in the wax blend had an impact on particle size distribution. Also, it had an impact on the surface morphology and thermal properties. The obtained results may contribute to the development of methods of encapsulation of hydrophobic aromas in the natural wax matrix.

Comparison of soil texture determined by two dispersion units of Mastersizer 2000

2012 ◽  
Vol 26 (1) ◽  
pp. 99-102 ◽  
Author(s):  
A. Sochan ◽  
A. Bieganowski ◽  
M. Ryżak ◽  
R. Dobrowolski ◽  
P. Bartmiński
Keyword(s):  
Particle Size ◽  
Soil Texture ◽  
Clay Fraction ◽  
Laser Diffraction ◽  
Size Distributions ◽  
Particle Size Distributions ◽  
Clay Particles ◽  
Fine Clay

Comparison of soil texture determined by two dispersion units of Mastersizer 2000The comparison of particle size distributions measured by sedimentation methods and laser diffraction shows the underestimation of the fine (clay) fraction. This is attributed mainly to the shape of clay particles being different than spherical. The objective of this study was to demonstrate differences in the results of particle size distributions of soils determined with the method of laser diffraction using two different dispersion units of the Malvern Mastersizer 2000.

STUDIES ON THE DYNAMICS OF "RECENTLY" CLAY-FIXED NH4+ USING 15N

1980 ◽  
Vol 60 (1) ◽  
pp. 61-70 ◽  
Author(s):  
C. G. KOWALENKO ◽  
G. J. ROSS
Keyword(s):  
Particle Size ◽  
Clay Fraction ◽  
Extraction Methods ◽  
Size Fractions ◽  
Particle Size Fractions ◽  
Fine Clay ◽  
Tracer Methods ◽  
Field And Laboratory Conditions ◽  
The Relationship ◽  
Fast Release

The dynamics of fixation and release of NH4+ in soils were studied using tracer N under field and laboratory conditions. Field data showed that release of fixed NH4+ was relatively slow after an initial moderately fast release. Forty months of field weathering of Bainsville soil left 3.48 kg 15N/ha in the 75-cm profile of the 13.5 kg 15N/ha applied and most (76%) of this recovered 15N was fixed NH4+–N. The relative quantitative importance of recently fixed NH4+ in the various particle size fractions was not in the same order as the native fixed NH4+. The fine silt fraction (2–5 μm) fixed a larger amount (whole soil basis) than the fine clay fraction (< 0.2 μm). The coarse clay fraction (0.2–2 μm) fixed the most NH4+ added as well as being the fraction containing the most native fixed NH4+. Sand size fractions were shown to contain native fixed NH4+ and were capable of fixing a small amount of added NH4+. Measurements of recently fixed NH4+–N in various particle sizes covering four time intervals (up to 40 mo) of field weathering under fallow showed that the 0.2 to 2-μm fraction was quantitatively most important, the < 0.2-μm fraction most readily released recently fixed NH4+ and the 2 to 5-μm fraction was the most stable with respect to recently fixed NH4+. Plant growth affected the relative stability of the recently fixed NH4+ in the various particle size fractions. Laboratory studies of three Brookston soil samples revealed higher estimates of fixation of NH4+ by direct tracer methods than by indirect extraction methods. This discrepancy was assumed to have been caused by some exchange of added NH4+ with native fixed NH4+ and by some NH4+ being fixed on other sites. The relationship between mineralogical and related analyses to fixation of NH4+ was discussed.

Effect of drainage on characteristics of some soils of the Orkney Islands

Soil Research ◽  
1994 ◽  
Vol 32 (3) ◽  
pp. 519 ◽  
Author(s):  
R Naidu ◽  
BD Mitchell ◽  
RC MacKenzie
Keyword(s):  
Salt Spray ◽  
Clay Fraction ◽  
Clay Mineralogy ◽  
Glacial Till ◽  
Soil Profiles ◽  
Red Sandstone ◽  
Orkney Islands ◽  
Drainage Class ◽  
Aluminosilicate Gel ◽  
Poorly Drained Soils

Three soil profiles with different degrees of drainage impedance developed on glacial till derived from Middle Old Red Sandstone sediments in the Orkney Islands were characterized texturally, chemically and mineralogically. Particular features of these soils were the high organic matter contents (9-50%) of the surface horizon soils resulting from high rainfall and cool temperatures. The high exchangeable Na+ and K+ contents in surface horizons of two of the pedons are a result of salt spray. The clay mineralogy and the nature and amount of aluminosilicate gel were affected by drainage class. In general, chlorite dominates the clay fraction of the imperfectly drained soil. However, with increasing impedence it was gradually displaced by mica which ultimately predominates in the very poorly drained saline gley. Vermiculitization occurred in the better drained soils. The poorly drained soils were distinguished by the absence of chlorite. Goethite was present in all soils but lepidocrocite occurred only when drainage was strongly impeded. Hematite was never present in these soils.

scholarly journals Particle Size Distribution of Natural Clayey Soils: A Discussion on the Use of Laser Diffraction Analysis (LDA)

Geosciences ◽  
2020 ◽  
Vol 10 (2) ◽  
pp. 55
Author(s):  
Aleksandra Gorączko ◽  
Szymon Topoliński
Keyword(s):  
Particle Size ◽  
Particle Size Distribution ◽  
Diffraction Analysis ◽  
Size Distribution ◽  
Clay Fraction ◽  
Laser Diffraction ◽  
Pedotransfer Functions ◽  
Clayey Soils ◽  
Selection Of

Particle size distribution is one of the most significant factors determining physical soil properties. Laser diffraction analysis (LDA) is an alternative method to the traditional hydrometric methods (HM) used to determine particle size distribution in soils. However, significant differences in fraction content are found in relation to the applied methods of a particle size test. Above all, measurements performed by LDA for clayey soils usually produce different results to those based on Stokes’ equation. Methodical problems, such as an appropriate method of dispersing the sample and the selection of LDA calculation theory, also play a significant role in fine soils. This paper contains the results of analyses of Neogene clays from Poland, which are characterized by differentiation with regard to the content of clay fraction particles. In this article, the validity of using laser diffraction analysis (LDA) for the identification and characterization of clayey sediments with common genesis is assessed. The possibility of finding reliable pedotransfer functions to the convert LDA results to a hydrometric analysis is discussed.

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