EXISTING AND POSSIBLE NEW GLEYSOLIC ORDER CRITERIA APPLIED TO FIVE PEDONS FROM BRITISH COLUMBIA

1986 ◽  
Vol 66 (2) ◽  
pp. 323-336 ◽  
Author(s):  
J. A. McKEAGUE ◽  
C. TARNOCAI ◽  
H. A. LUTTMERDING
Keyword(s):  
British Columbia ◽  
Thin Sections ◽  
Soil Water Regime ◽  
Reducing Conditions ◽  
Current Classification ◽  
Bulk Chemical ◽  
Iron Manganese ◽  
Iron And Manganese ◽  
Do So

Use of the current criteria for distinguishing Gleysolic soils from gleyed intergrades to other soil classes resulted in the apparent misclassification of some soils in British Columbia. Pedologists of the area selected five pedons encompassing several degrees of expression of gley features. Current classification criteria based on soil color and possible new differentiating features based on chemical and micromorphological analyses were applied in considering the classification of the soils. Application of the current specific color criteria involving low chromas and prominent mottling result in the classification of three pedons in the Gleysolic order and two in gleyed subgroups of other orders. This classification was appropriate in the view of B.C. pedologists except for one Gleysolic pedon in which the water table is rarely within 1 m of the surface. Prior to drainage, however, the soil was probably saturated to the surface and under reducing conditions for prolonged periods each year. Thus, classification as a Gleysolic soil is appropriate as it probably reflects the prevailing conditions and processes during most of the period of soil genesis.Segregation of iron and manganese as nodules and coatings was most marked in the Gleysolic pedons. Walls of some voids were bleached due to depletion of iron oxides. Though study of thin sections, bulk chemical analysis and analysis of specific features by scanning electron microscopy-energy dispersive X-ray analysis (SEM-EDXRA) were useful in providing information on soil properties, they did not indicate an improved basis for differentiating Gleysolic soils from others. The color criteria used to distinguish soils of the Gleysolic order do not necessarily reflect the current soil water regime, and they are not intended to do so. The current criteria resulted in the appropriate classification of the five soils. Key words: Gleying, reduction, iron, manganese, micromorphology, SEM-EDXRA

Iron and manganese release in coal mine drainage wetland microcosms

1995 ◽  
Vol 32 (3) ◽  
pp. 187-192 ◽  
Author(s):  
W. J. Tarutis ◽  
R. F. Unz
Keyword(s):  
Metal Oxides ◽  
Constructed Wetlands ◽  
Metal Ion ◽  
Manganese Oxides ◽  
Mine Drainage ◽  
Organic Substrate ◽  
Mushroom Compost ◽  
Reducing Conditions ◽  
Iron Manganese ◽  
Iron And Manganese

The primary mechanisms responsible for the removal and retention of iron, manganese, and sulfate in constructed wetlands receiving acidic mine drainage (AMD) include the formation of metal oxides and sulfides within the sediments. This study was initiated to determine the kinetics of metal ion liberation, under reducing conditions, from synthetic and naturally occurring iron and manganese oxides typically found in AMD precipitates. Rates of metal ion liberation were determined during time series incubations of an organic substrate (spent mushroom compost) to which five metal oxides of varying crystallinity (amorphous and crystalline oxides of iron and manganese; natural AMD oxide) were added. All experiments were carried out in silicone-sealed polycarbonate centrifuge tubes incubated at 22°C for a period of 3, 7, 10, 14, 21 or 28 days. Tubes were sacrificed after each incubation period and were analyzed for redox potential, pH, sulfide, and metals. All tubes exhibited reducing potentials within 3 days coupled with rapidly increasing concentrations of iron and manganese. Liberation of iron and manganese decreased with increasing mineral crystallinity (amorphous > natural AMD ≫ crystalline). The results suggest that metal ion liberation from oxide minerals may be an important source of iron and manganese within constructed wetlands receiving AMD.

scholarly journals ENRICHMENT FACTORS OF HEAVY METALS IN IRON - MANGANESE CONCRETIONS FROM IMPERFECTLY DRAINED SOILS

2018 ◽  
Vol 36 (1) ◽  
pp. 158 ◽  
Author(s):  
Δ. Γασπαράτος ◽  
Κ. Χαϊντούτη ◽  
Δ. Ταρενίδης ◽  
Α. Τσαγκαλίδης
Keyword(s):  
Heavy Metals ◽  
Manganese Oxides ◽  
Enrichment Factors ◽  
Soil System ◽  
Charged Surfaces ◽  
Lead And Cadmium ◽  
Reducing Conditions ◽  
Iron Manganese ◽  
Mn Oxides ◽  
Iron And Manganese

The Fe-Mn concretions are morphological features of soils under alternating oxidizing and reducing conditions. They have a high adsorption capacity for many inorganic pollutants, like heavy metals. This study determines the enrichment factors of Fe, Μη, Ni, Co, Pb and Cd in Fe-Mn concretions collected from imperfectly -drained soils in Central Greece. The data show that the concretions absorbed significant amounts of heavy metals and especially of lead and cadmium from the soil system. According to the enrichment factors, the affinity of heavy metals for the concretions due to the charged surfaces of iron and manganese oxides, follow the order Pb>Cd>Mn>Co>Ni>Fe. McKenzie (1980) also found adsorption of cobalt, manganese, nickel and lead at the same order on nine synthetic manganese oxides while Nimfopoulos et al. (1997) showed that the mobility of the metals at karst cavities enriched with Mn oxides followed the order Na>K>Mg>Sr>Mn>As>Zn>Ba>AI>Fe>Cu>Cd>Pb.

MICROSCOPIC FEATURES OF CERTAIN ALBERTA COALS

1936 ◽  
Vol 14b (8) ◽  
pp. 275-298
Author(s):  
I. W. Jones
Keyword(s):  
British Columbia ◽  
Microscopic Examination ◽  
Resin Content ◽  
Wide Field ◽  
Southwestern Part ◽  
Thin Sections ◽  
Coal Deposits ◽  
Microscopic Features

Microscopic examination of Alberta coals shows that they are composed principally of materials derived from the woody parts of plants. Many woody structures are visible in thin sections and on polished and etched surfaces. Spores are present in the coals, but are relatively few in number. The resin content varies considerably, attaining a high proportion in the cannel coals of the Crowsnest Pass region in British Columbia, bordering the southwestern part of Alberta. The correlation of seams in the Alberta coal deposits on the basis of their microscopical characters has not yet proved to be feasible. A wide field is open here for palaeobotanical research on the nature and classification of the plant structures visible in these coals by means of the microscope. The investigation described here may be considered as being relatively only a beginning to further work that should be done in the study of the microscopical features of Alberta coals by the geologist, chemist and botanist.

THE SEC PREEMPTS THE ACCOUNTING PRINCIPLES BOARD IN 1965: THE CLASSIFICATION OF THE DEFERRED TAX CREDIT RELATING TO INSTALLMENT SALES

2007 ◽  
Vol 34 (1) ◽  
pp. 1-23 ◽  
Author(s):  
Stephen A. Zeff
Keyword(s):  
Securities And Exchange Commission ◽  
Accounting Practice ◽  
Slow Pace ◽  
Accounting Principles ◽  
Private And Public ◽  
Deferred Tax ◽  
Accounting Procedure ◽  
The U.S ◽  
Do So

In 1959, the Accounting Principles Board (APB) replaced the Committee on Accounting Procedure because the latter was unable to deal forthrightly with a series of important issues. But during the APB's first half-dozen years, its record of achievement was no more impressive than its predecessor's. The chairman of the Securities and Exchange Commission (SEC), Manuel F. Cohen, criticized the APB's slow pace and unwillingness to tackle difficult issues. This article discusses the circumstances attending the SEC's issuance of an Accounting Series Release in late 1965 to demonstrate forcefully to the APB that, when it is unable to carry out its responsibility to “narrow the areas of difference” in accounting practice, the SEC is prepared to step in and do so itself. In this sense, the article deals with the tensions between the private and public sectors in the establishment of accounting principles in the U.S. during the mid-1960s. The article makes extensive use of primary resource materials in the author's personal archive, which have not been used previously in published work.

scholarly journals Insights into phylogenetic relationships and genome evolution of subfamily Commelinoideae (Commelinaceae Mirb.) inferred from complete chloroplast genomes

BMC Genomics ◽  
2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Joonhyung Jung ◽  
Changkyun Kim ◽  
Joo-Hwan Kim
Keyword(s):  
Nucleotide Diversity ◽  
Structural Variations ◽  
Protein Coding ◽  
Protein Coding Genes ◽  
Chloroplast Protein ◽  
Genome Data ◽  
Plastid Genomes ◽  
Chloroplast Genomes ◽  
Current Classification

Abstract Background Commelinaceae (Commelinales) comprise 41 genera and are widely distributed in both the Old and New Worlds, except in Europe. The relationships among genera in this family have been suggested in several morphological and molecular studies. However, it is difficult to explain their relationships due to high morphological variations and low support values. Currently, many researchers have been using complete chloroplast genome data for inferring the evolution of land plants. In this study, we completed 15 new plastid genome sequences of subfamily Commelinoideae using the Mi-seq platform. We utilized genome data to reveal the structural variations and reconstruct the problematic positions of genera for the first time. Results All examined species of Commelinoideae have three pseudogenes (accD, rpoA, and ycf15), and the former two might be a synapomorphy within Commelinales. Only four species in tribe Commelineae presented IR expansion, which affected duplication of the rpl22 gene. We identified inversions that range from approximately 3 to 15 kb in four taxa (Amischotolype, Belosynapsis, Murdannia, and Streptolirion). The phylogenetic analysis using 77 chloroplast protein-coding genes with maximum parsimony, maximum likelihood, and Bayesian inference suggests that Palisota is most closely related to tribe Commelineae, supported by high support values. This result differs significantly from the current classification of Commelinaceae. Also, we resolved the unclear position of Streptoliriinae and the monophyly of Dichorisandrinae. Among the ten CDS (ndhH, rpoC2, ndhA, rps3, ndhG, ndhD, ccsA, ndhF, matK, and ycf1), which have high nucleotide diversity values (Pi > 0.045) and over 500 bp length, four CDS (ndhH, rpoC2, matK, and ycf1) show that they are congruent with the topology derived from 77 chloroplast protein-coding genes. Conclusions In this study, we provide detailed information on the 15 complete plastid genomes of Commelinoideae taxa. We identified characteristic pseudogenes and nucleotide diversity, which can be used to infer the family evolutionary history. Also, further research is needed to revise the position of Palisota in the current classification of Commelinaceae.

scholarly journals Morphological and Ultrastructural Characterization of Hemocytes in an Insect Model, the Hematophagous Dipetalogaster maxima (Hemiptera: Reduviidae)

Insects ◽  
2021 ◽  
Vol 12 (7) ◽  
pp. 640
Author(s):  
Natalia R. Moyetta ◽  
Fabián O. Ramos ◽  
Jimena Leyria ◽  
Lilián E. Canavoso ◽  
Leonardo L. Fruttero
Keyword(s):  
Cell Biology ◽  
Cell Types ◽  
Transmission Electron ◽  
Ultrastructural Characterization ◽  
Current Classification ◽  
Contrast Microscopy ◽  
First Time ◽  
Controversial Aspect

Hemocytes, the cells present in the hemolymph of insects and other invertebrates, perform several physiological functions, including innate immunity. The current classification of hemocyte types is based mostly on morphological features; however, divergences have emerged among specialists in triatomines, the insect vectors of Chagas’ disease (Hemiptera: Reduviidae). Here, we have combined technical approaches in order to characterize the hemocytes from fifth instar nymphs of the triatomine Dipetalogaster maxima. Moreover, in this work we describe, for the first time, the ultrastructural features of D. maxima hemocytes. Using phase contrast microscopy of fresh preparations, five hemocyte populations were identified and further characterized by immunofluorescence, flow cytometry and transmission electron microscopy. The plasmatocytes and the granulocytes were the most abundant cell types, although prohemocytes, adipohemocytes and oenocytes were also found. This work sheds light on a controversial aspect of triatomine cell biology and physiology setting the basis for future in-depth studies directed to address hemocyte classification using non-microscopy-based markers.

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