Structural decline of soils, assessment and prevention

Soil Research ◽  
1991 ◽  
Vol 29 (6) ◽  
pp. 905 ◽  
Author(s):  
WW Emerson
Keyword(s):  
Structural Damage ◽  
Soil Aggregates ◽  
Total Porosity ◽  
Field Capacity ◽  
The Other ◽  
Clay Soils ◽  
Particle Bonding ◽  
Remoulded Soil ◽  
Cracking Clays

Two extreme textural types of cultivated surface soils are mainly considered here, non-shrinking red-brown earths and highly shrinking cracking clays. Total porosity is used to assess the structural status of the former. Values are compared with the highest and lowest values found in the field. For the latter, the criterion used is the porosity of dry aggregates or clods. Values here are taken from the literature. To find out why inter-particle bonding in soil aggregates is insufficient to stop structural decline, a scheme has been developed which includes a modified version of Emerson's (1967) classification of soil aggregates. Slaking is carefully assessed. The bulk density of a cube made from soil at 'field capacity' is measured as well as testing another for dispersion. Class 3 is now divided into 3a and 3b, according to the degree of dispersion of remoulded soil in water. Also apart from soils which disperse spontaneously from dry, classes 1 and 2, the dispersion of all soils is assessed after remoulding at 'field capacity'. It has been found that the red-brown earth site which had the best visual structure also had the largest total porosity and aggregates in class 4. At the worst site, aggregates were in class 3a and the porosity had been reduced to that of the soil cube. For cracking clays, porosity is appreciably higher where the aggregates are in class 4 rather than class 3a. Water content/dispersion curves are presented for the clays showing the extent of the increase in OD apparently associated with the presence of carbonate. Dispersion of sheared, class 3a soil immersed in water is only an outward sign of the structural damage caused when the soil is sheared too wet. If the soil is dried instead, porosity is still lost. Mechanisms are suggested by which the structure of class 3a clay soils are improved by adding carbonate. The slumping of red-brown earths and the use of surface dressings of gypsum to prevent severe dispersion after cultivation wet are discussed. The structural stability of aggregates in the other five classes is briefly considered. Classes 1 and 2 require an ameliorant to be added, the rest pose few problems.

USE OF SOIL CORES IN SOIL CLASSIFICATION

1961 ◽  
Vol 41 (2) ◽  
pp. 241-246
Author(s):  
J. A. Toogood
Keyword(s):  
Statistical Study ◽  
Soil Classification ◽  
Total Porosity ◽  
Field Capacity ◽  
Soil Types ◽  
Soil Cores ◽  
Conductivity Measurements ◽  
Volume Weight ◽  
Tension Plate

The value of soil cores in soil classification was examined by a statistical study of the physical properties of five soil types, using 3 × 3-inch soil cores. Analyses of variance when five replicates were used showed that field capacity differences of about 5 per cent could be detected throughout the solum of these soils. Distinctions in volume weight and total porosity were readily made, significance differences (P = 0.95) being about 0.1 gram per cubic centimetre and 4 per cent respectively. Tension plate measurements were precise enough to show significant differences between some of the soils in the Ah horizon but between none in the Bt horizon. Hydraulic conductivity measurements seemed to be of little value as no differences in the five soils could be demonstrated statistically. The results obtained indicate that routine tests of this kind by soil surveyors would yield some useful information and assist in the classification of soils.

scholarly journals Soil Water Studies in Oxisols and Ultisols of Puerto Rico: I. Water Movement

1969 ◽  
Vol 60 ◽  
pp. 375-385
Author(s):  
James M. Wolf ◽  
Matthew Drosdoff
Keyword(s):  
Soil Water ◽  
Water Movement ◽  
Soil Aggregates ◽  
Flow Characteristics ◽  
Field Capacity ◽  
Water Infiltration ◽  
Clay Soils ◽  
Water Release ◽  
Soil Water Tension ◽  
Free Drainage

Soil water experiments were conducted to determine the water supplying characteristics of two clayey Ultisols, a clayey Oxisol, and a sandy Oxisol. Water infiltration into all soils was very rapid, reaching 9 cm/hr after 1 hr of continuous flooding. The strong structural stability of the clay soils permitted infiltration rates in excess of that for the sandy soil. Lateral water movement, downslope, was a significant factor in observed high rates of water infiltration and may partially account for downslope movement of nitrates. Values of soil water tension after 2 to 3 days of free drainage did not exceed 20 to 80 cm of water (roughly 1/50 to 1/12 bar). Field capacity was established to be 1/15 bar for the sandy Oxisol and 1/20 bar for the clayey Oxisol and Ultisols. Two avenues of soil water movement were postulated: Capillary pores (between soil particles) and non-capillary pores (between soil aggregates). Because of water movement in non-capillary pores, flow characteristics of the clay soils resembled that of the sand. In terms of soil water release characteristics, the clays and the sand were similar.

scholarly journals Soil consistency as a factor determining the soil structure of clay soils.

1956 ◽  
Vol 4 (1) ◽  
pp. 122-125 ◽  
Author(s):  
P. Boekel ◽  
P.L. Peerlkamp
Keyword(s):  
Soil Structure ◽  
Soil Aggregates ◽  
Field Capacity ◽  
Clay Soils ◽  
Mechanical Forces ◽  
Plastic Limit ◽  
Top Soil ◽  
Moisture Percentage ◽  
Soil Conditioners ◽  
Plastic Transformation

The deterioration of the aggregation of several Dutch clay soils during the period after plowing seems to be caused by a plastic transformation of the soil aggregates under the influence of mechanical forces, even very weak ones such as the weight of the top soil. It depends on the consistency and moisture characteristics of the soil, the drainage of the top soil, etc. The location of the point pF 1.9 ("field capacity") on the moisture percentage scale with regard to the upper plastic limit, the sticky point and the lower plastic limit appears to be a better index for the structure of clay soils than figures obtained from a wet-sieving analysis, and some results of experiments on the effects of lime, gypsum and soil conditioners on soil structure illustrate this.-From authors' summary. (Abstract retrieved from CAB Abstracts by CABI’s permission)

Consistency in Latency Measurements and Interpretation of ABR Tracings

1997 ◽  
Vol 6 (1) ◽  
pp. 57-62 ◽  
Author(s):  
Wayne O. Olsen ◽  
Terri L. Pratt ◽  
Christopher D. Bauch
Keyword(s):  
The Other

Multichannel ABR recordings for 30 otoneurologic patients were reviewed independently by three audiologists to assess interjudge consistency in determining absolute latencies and overall interpretation of ABR results. Four months later, the tracings were reviewed a second time to evaluate intrajudge consistency in interpretation of ABR waveforms. Interjudge agreement in marking latencies for waves I, III, and V within 0.2 ms was on the order of 90% or better. Intrajudge consistency was slightly higher. Only rarely did inter- or intrajudge differences in latency measurements exceed 0.3 ms. Agreement in overall interpretation of ABR results as "normal" or "abnormal" was unanimous for 90% of the patients. Across pairs of judges, the agreement for "normal" and "abnormal" classification of the ABR tracings was 97%. Intrajudge consistency for "normal" and "abnormal" categorization of the ABR results was 100% for one judge, 97% for the other two judges.

RHYNCHOLITES AND THE PROBLEM OF NARROW AND BROAD CONCEPTION OF TAXONS

2018 ◽  
pp. 12-17 ◽  
Author(s):  
I. R. Khuzina ◽  
V. N. Komarov
Keyword(s):  
Sexual Dimorphism ◽  
Morphological Characteristics ◽  
Mass Scale ◽  
Individual Variability ◽  
Point Of View ◽  
The Other ◽  
New Taxon ◽  
Artificial System ◽  
Broad Understanding

The paper considers a point of view, based on the conception of the broad understanding of taxons. According to this point of view, rhyncholites of the subgenus Dentatobeccus and Microbeccus are accepted to be synonymous with the genus Rhynchoteuthis, and subgenus Romanovichella is considered to be synonymous with the genus Palaeoteuthis. The criteria, exercising influence on the different approaches to the classification of rhyncholites, have been analyzed (such as age and individual variability, sexual dimorphism, pathological and teratological features, degree of disintegration of material), underestimation of which can lead to inaccuracy. Divestment of the subgenuses Dentatobeccus, Microbeccus and Romanovichella, possessing very bright morphological characteristics, to have an independent status and denomination to their synonyms, has been noted to be unjustified. An artificial system (any suggested variant) with all its minuses is a single probable system for rhyncholites. The main criteria, minimizing its negative sides and proving the separation of the new taxon, is an available mass-scale material. The narrow understanding of the genus, used in sensible limits, has been underlined to simplify the problem of the passing the view about the genus to the other investigators and recognition of rhyncholites for the practical tasks.

Somatoform disorders: diseases of the civilization

2020 ◽  
pp. 25-30
Author(s):  
I. Kukhtevich
Keyword(s):  
Health Professionals ◽  
Somatoform Disorders ◽  
Neuropsychiatric Disorders ◽  
The Other ◽  
Significant Part ◽  
Organic Basis ◽  
Autonomic Disorders ◽  
The One ◽  
Somatic Diseases

Functional autonomic disorders occupy a significant part in the practice of neurologists and professionals of other specialties as well. However, there is no generally accepted classification of such disorders. In this paper the authors tried to show that functional autonomic pathology corresponds to the concept of somatoform disorders combining syndromes manifested by visceral, borderline psychopathological, neurological symptoms that do not have an organic basis. The relevance of the problem of somatoform disorders is that on the one hand many health professionals are not familiar enough with manifestations of borderline neuropsychiatric disorders, often forming functional autonomic disorders, and on the other hand they overestimate somatoform symptoms that are similar to somatic diseases.

STUDY OF ORNAMENTS IN HUNTO SULTAN AMAY MOSQUE GORONTALO

ARTic ◽  
2019 ◽  
Vol 4 ◽  
pp. 167-176
Author(s):  
Risti Puspita Sari Hunowu
Keyword(s):  
Qualitative Method ◽  
The Other ◽  
Visual Form ◽  
Research Material ◽  
Other Hand ◽  
The World ◽  
Existing Form ◽  
The City ◽  
Dutch Colonial

This research is aimed at studying the Hunto Sultan Amay Mosque located in Gorontalo City. Hunto Sultan Amay Mosque is the oldest mosque in the city of Gorontalo The Hunto Sultan Amay Mosque was built as proof of Sultan Amay's love for a daughter and is a representation of Islam in Gorontalo. Researchers will investigate the visual form of the Hunto Sultan Amay Mosque which was originally like an ancient mosque in the archipelago. can be seen from the shape of the roof which initially used an overlapping roof and then converted into a dome as well as mosques in the world, we can be sure the Hunto Sultan Amay Mosque uses a dome roof after the arrival of Dutch Colonial. The researcher used a qualitative method by observing the existing form in detail from the building of the mosque with an aesthetic approach, reviewing objects and selecting the selected ornament giving a classification of the shapes, so that the section became a reference for the author as research material. Based on the analysis of this thesis, the form  of the Hunto Sultan Amay mosque as well as the mosques located in the archipelago and the existence of ornaments in the Hunto Sultan Amay Mosque as a decorative structure support the grandeur of a mosque. On the other hand, Hunto Mosque ornaments reveal a teaching. The form of a teaching is manifested in the form of motives and does not depict living beings in a realist or naturalist manner. the decorative forms of the Hunto Sultan Sultan Mosque in general tend to lead to a form of flora, geometric ornaments, and ornament of calligraphy dominated by the distinctive colors of Islam, namely gold, white, red, yellow and green.

scholarly journals PoreAnalyzer—An Open-Source Framework for the Analysis and Classification of Defects in Additive Manufacturing

2021 ◽  
Vol 11 (13) ◽  
pp. 6086
Author(s):  
Nils Ellendt ◽  
Fabian Fabricius ◽  
Anastasiya Toenjes
Keyword(s):  
Additive Manufacturing ◽  
Open Source ◽  
Total Porosity ◽  
Shape Accuracy ◽  
Process Maps ◽  
Defect Type ◽  
Open Source Framework ◽  
New Material ◽  
High Cooling Rates

Additive manufacturing processes offer high geometric flexibility and allow the use of new alloy concepts due to high cooling rates. For each new material, parameter studies have to be performed to find process parameters that minimize microstructural defects such as pores or cracks. In this paper, we present a system developed in Python for accelerated image analysis of optical microscopy images. Batch processing can be used to quickly analyze large image sets with respect to pore size distribution, defect type, contribution of defect type to total porosity, and shape accuracy of printed samples. The open-source software is independent of the microscope used and is freely available for use. This framework allows us to perform such an analysis on a circular area with a diameter of 5 mm within 10 s, allowing detailed process maps to be obtained for new materials within minutes after preparation.

scholarly journals A taxonomy of antonymy in Arabic: Egyptian and Saudi proverbs in comparison

2021 ◽  
Vol 7 (1) ◽  
pp. 200-222
Author(s):  
Hamada Hassanein ◽  
Mohammad Mahzari
Keyword(s):  
Main Clause ◽  
The Other ◽  
Subordinate Clause ◽  
Future Research ◽  
Case Marking ◽  
News Discourse ◽  
Discourse Functions ◽  
Syntactic Frames

Abstract This study has set out to identify, quantify, typify, and exemplify the discourse functions of canonical antonymy in Arabic paremiography by comparing two manually collected datasets from Egyptian and Saudi (Najdi) dialects. Building upon Jones’s (2002) most extensive and often-cited classification of the discourse functions of antonyms as they co-occur within syntactic frames in news discourse, the study has substantially revised this classification and developed a provisional and dynamic typology thereof. Two major textual functions are found to be quantitatively significant and qualitatively preponderant: ancillarity (wherein an A-pair of canonical antonyms project their antonymicity onto a more important B-pair) and coordination (wherein one antonym holds an inclusive or exhaustive relation to another antonym). Three new functions have been developed and added to the retrieved classification: subordination (wherein one antonym occurs in a subordinate clause while the other occurs in a main clause), case-marking (wherein two opposite cases are served by two antonyms), and replacement (wherein one antonym is substituted with another). Semicanonical and noncanonical guises of antonymy are left and recommended for future research.

Individual and Community: The Changing Role of Megaliths in the Orcadian Neolithic

1985 ◽  
Vol 51 (1) ◽  
pp. 59-74 ◽  
Author(s):  
Niall Sharples
Keyword(s):  
The Other ◽  
Significant Problem ◽  
Neolithic Period ◽  
Size Type ◽  
The Individual ◽  
Changing Role

This paper is an exploration of the chronological development of a series of elaborate and architecturally distinctive chambered tombs on the Islands of Orkney. It begins with a short critique of the present views of the Orcadian Neolithic and highlights a failure to understand chronological developments as the most significant problem. Thus after a brief classification of the monuments there is a detailed discussion of the chronological evidence which consciously avoids typological assumptions. This is followed by an examination of the various uses the tombs were put to and involves an assessment of the location and architectural visibility of the monuments and the remains found in the chamber. When combined with the chronological evidence a series of changes in monument size, type, location and use can be hypothesized for the neolithic period. This culminates in a shift away from burial monuments to physically defined spaces, presumably used for ceremonial purposes. These changes can be interpreted as deliberate manipulation by groups within that society to change the ideological concepts which defined the role of the individual in relation to the other members of the society.

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