Regional geochemical mapping in areas lacking surface drainages: Cu, Fe, Mn, and Zn content of overburden and soil in south-central Saskatchewan

1979 ◽  
Vol 16 (5) ◽  
pp. 1086-1093 ◽  
Author(s):  
P. J. Doyle ◽  
W. K. Fletcher
Keyword(s):  
Statistical Significance ◽  
Parent Material ◽  
Geochemical Mapping ◽  
Parent Materials ◽  
South Central ◽  
Zn Content ◽  
Mean And Variance ◽  
Mean Differences ◽  
Iron Manganese ◽  
Range Test

An approach to regional geochemical mapping is outlined utilizing differences among mean metal concentrations for soil associated with individual parent materials. Initially the area of study is divided into parent material-based subareas for soil collection. Separate mean and variance metal values are estimated for each parent material and Duncan's Multiple Range Test is used to evaluate the statistical significance of among mean differences. Results are summarized in map form showing only compositionally distinctive parent materials or parent material groups and their associated mean and range values.This approach was tested in the Rosetown–Outlook area of south-central Saskatchewan. Results suggest that, in total, fewer than 10 samples are required per parent material to produce stable maps for copper, iron, manganese, and zinc in this 10 000 km2 area. Because of the limited number of samples needed, the method is both rapid and relatively inexpensive. It is therefore ideally suited for regional geochemical surveying, particularly in relatively arid areas where conventional lake and stream sediment-based procedures are not applicable.

scholarly journals Morphology and Composition of Two Late Wisconsinan Soils Forming in Till and Lacustrine Deposits, Scarborough Bluffs Area, South-Central Ontario

2007 ◽  
Vol 39 (3) ◽  
pp. 307-314 ◽  
Author(s):  
William C. Mahaney
Keyword(s):  
Chemical Properties ◽  
Parent Material ◽  
Mineral Contents ◽  
Parent Materials ◽  
Lacustrine Deposits ◽  
South Central ◽  
Primary Mineral ◽  
Physical Attributes ◽  
Late Wisconsinan ◽  
Sand And Gravel

ABSTRACT Halton Till and Glacial Lake Iroquois lacustrine sand and gravel deposits are the major surficial materials exposed at the surface of Scarborough Bluffs in South-Central Ontario. Luvisols formed in these deposits have different morphologies, including depth of weathering, complexity of horizonation, and strength of structural grades which result from parent material differences and pedogenesis. Particle size variations between the two paleosols result, in part, from different modes of deposition, and show that variable amounts of clay were produced pedogenically in the two systems. Clay mineral genesis, involving the transformation of illite and illitesmectite to vermiculite, appears to be restricted to the Iroquois sand paleosol, while some chloritization of illite occurs in both profiles. Changes in the primary mineral contents in the two paleosols suggest a similar magnitude of weathering in both systems. Distributions of vermiculite and dithionite-extractable Fe suggest some preweathering effects in the Halton Till paleosol. Morphological, mineralogical and some soil chemical properties are closely related to the physical attributes of the two different parent materials (till vs lacustrine sand and gravel).

CARBONATE MINERALOGY OF LAKE SEDIMENTS AND SURROUNDING SOILS. 2. THE QU’APPELLE LAKES

1983 ◽  
Vol 63 (2) ◽  
pp. 259-269 ◽  
Author(s):  
K. GHEBRE-EGZIABHIER ◽  
R. J. ST. ARNAUD
Keyword(s):  
Lake Sediments ◽  
Particle Size Analysis ◽  
Parent Material ◽  
Size Analysis ◽  
Carbonate Content ◽  
Mineral Contents ◽  
Ionic Activity ◽  
South Central ◽  
Direct Precipitation ◽  
Lake Waters

The nature and distribution of carbonate minerals in the upper Qu’Appelle basin in south-central Saskatchewan were investigated. The equivalent carbonate content and calcite:dolomite ratios of the deposits reflect the mechanisms of glacial deposition and some differences in the sources of the original parent material. The particle size analysis shows that the Qu’Appelle Lake sediments are more clayey than the surrounding soils and till deposits. Mg-bearing calcites occur only in the fine-sized fraction of the carbonate accumulation horizons. However, most of the upper Qu’Appelle Lake sediments contain appreciable amounts of sand-sized Mg-bearing calcites. The marked increase in carbonate content of the sediments relative to the adjacent soils and deposits is partially due to direct precipitation of calcite from the supersaturated lake waters. In this respect, a good correlation exists between the lake water ionic activity products for CaCO3 and the relative equivalent carbonatic mineral contents of the sediments. Key words: Mg-bearing calcite, dolomite, IAP, erosion

The effect of 0.01% atropine on ocular axial elongation for myopia children: a meta-analysis

2021 ◽  
Author(s):  
Yan Yu ◽  
Jiasu Liu
Keyword(s):  
Publication Bias ◽  
Meta Analysis ◽  
Statistical Significance ◽  
Cochrane Library ◽  
Axial Elongation ◽  
Funnel Plots ◽  
Mean Differences ◽  
Q Statistic ◽  
Regression Tests ◽  
Review Manager

Objectives: This meta-analysis aimed to identify the therapeutic effect of 0.01% atropine with on ocular axial elongation for myopia children. Methods: We searched PubMed, Cochrane Library, and CBM databases from inception to July 2021. Meta-analysis was conducted using STATA version 14.0 and Review Manager version 5.3 softwares. We calculated the weighted mean differences(WMD) to analyze the change of ocular axial length (AL) between orthokeratology combined with 0.01% atropine (OKA) and orthokeratology (OA) alone. The Cochran's Q-statistic and I2 test were used to evaluate potential heterogeneity between studies. To evaluate the influence of single studies on the overall estimate, a sensitivity analysis was performed. We also performed sub group and meta-regression analyses to investigate potential sources of heterogeneity. We conducted Begger's funnel plots and Egger's linear regression tests to investigate publication bias. Results: Nine studies that met all inclusion criteria were included in this meta-analysis. A total of 191 children in OKA group and 196 children in OK group were assessed. The pooled summary WMD of AL change was -0.90(95%CI=-1.25~-0.55) with statistical significance(t=-5.03, p<0.01), which indicated there was obvious difference between OKA and OK in myopic children. Subgroup analysis also showed that OKA treatment resulted in significantly less axial elongation compared to OK treatment alone according to SER. We found no evidence for publication bias. Conclusions:  Our meta-analysis indicates 0.01% atropine atropine is effective in slowing axial elongation in myopia children with orthokeratology.

scholarly journals FRACTIONATION OF THE HUMUS OF SOME CHERNOZEMIC SOILS OF SOUTHERN ALBERTA

1964 ◽  
Vol 44 (2) ◽  
pp. 232-236 ◽  
Author(s):  
J. F. Dormaar
Keyword(s):  
Humic Acid ◽  
Carbon Content ◽  
Black Soil ◽  
Parent Material ◽  
Glacial Till ◽  
Total Carbon ◽  
Total Carbon Content ◽  
Parent Materials ◽  
Southern Alberta ◽  
Alcohol Benzene

Two orthic profiles, widely separated geographically, of each of four parent materials—lacustrine, alluvial–lacustrine, glacial till, and Aeolian—were selected at undisturbed sites within each of the Brown, Dark Brown, and Thin Black soil zones. Material from the Ah and Bm horizons was subjected to solvent extraction, and for each sample the total organic carbon of seven different fractions was determined.The efficiency of the procedure in extracting humus carbon decreased as the total carbon content of the soil increased. Total organic matter, the first humic acid fraction, and the combined total of the three humic acid fractions showed significant differences between soil zones. The only significant separation between all four parent materials was made by the alcohol-benzene fraction. Other parent material separations were possible only following the summation of data of several fractions, such as the three humic acid fractions or the two fulvic acid fractions. A simplification of the procedure in case of soils of one Order and a modification to overcome the impeding effect of increased carbon content are requisite.

Influence of parent material on clay minerals formation in Podzols of Trentino, Italy

Clay Minerals ◽  
2002 ◽  
Vol 37 (4) ◽  
pp. 699-707 ◽  
Author(s):  
A. Mirabella ◽  
M. Egli ◽  
S. Carnicelli ◽  
G. Sartori
Keyword(s):  
Organic Carbon ◽  
Clay Minerals ◽  
Clay Mineral ◽  
Parent Material ◽  
Soil Horizons ◽  
Parent Materials ◽  
Subalpine Belt ◽  
Mineral Assemblages ◽  
Mineral Components ◽  
Interstratified Mineral

AbstractThe formation of clay minerals was investigated in Spodosols developed in the subalpine belt, with similar exposure, climate and age, but deriving from different parent materials. All the soils were classified as Haplic Podzols and showed the characteristic eluviation and illuviation features of Fe, Al and organic carbon. However, varying parent material lithology led to different clay mineral assemblages in the soil. Smectite could be found in the E horizons of soils developed from granodiorite and tonalite materials. Its formation was strongly dependent on the presence of chlorite in the parent material. If nearly no other 2:1 mineral components, such as chlorite, are present in the lower soil horizons, then a residual micaceous mineral becomes the dominant clay mineral. The latter derives from a mica-vermiculite interstratified mineral.

scholarly journals Interactions between organisms and parent materials of a constructed Technosol shape its hydrostructural properties

SOIL ◽  
2016 ◽  
Vol 2 (2) ◽  
pp. 163-174 ◽  
Author(s):  
Maha Deeb ◽  
Michel Grimaldi ◽  
Thomas Z. Lerch ◽  
Anne Pando ◽  
Agnès Gigon ◽  
...  
Keyword(s):  
Parent Material ◽  
Material Composition ◽  
Positive Role ◽  
Parent Materials ◽  
Positive Effects ◽  
Available Water ◽  
Set Up ◽  
Full Factorial ◽  
Positive Effect ◽  
Better Than

Abstract. There is no information on how organisms influence hydrostructural properties of constructed Technosols and how such influence will be affected by the parent-material composition factor. In a laboratory experiment, parent materials, which were excavated deep horizons of soils and green waste compost (GWC), were mixed at six levels of GWC (from 0 to 50 %). Each mixture was set up in the presence/absence of plants and/or earthworms, in a full factorial design (n  =  96). After 21 weeks, hydrostructural properties of constructed Technosols were characterized by soil shrinkage curves. Organisms explained the variance of hydrostructural characteristics (19 %) a little better than parent-material composition (14 %). The interaction between the effects of organisms and parent-material composition explained the variance far better (39 %) than each single factor. To summarize, compost and plants played a positive role in increasing available water in macropores and micropores; plants were extending the positive effect of compost up to 40 and 50 % GWC. Earthworms affected the void ratio for mixtures from 0 to 30 % GWC and available water in micropores, but not in macropores. Earthworms also acted synergistically with plants by increasing their root biomass, resulting in positive effects on available water in macropores. Organisms and their interaction with parent materials positively affected the hydrostructural properties of constructed Technosols, with potential positive consequences on resistance to drought or compaction. Considering organisms when creating Technosols could be a promising approach to improve their fertility.

scholarly journals Prevention of Delayed Nausea: A University of Rochester Cancer Center Community Clinical Oncology Program Study of Patients Receiving Chemotherapy

2012 ◽  
Vol 30 (27) ◽  
pp. 3389-3395 ◽  
Author(s):  
Joseph A. Roscoe ◽  
Charles E. Heckler ◽  
Gary R. Morrow ◽  
Supriya G. Mohile ◽  
Shaker R. Dakhil ◽  
...  
Keyword(s):  
Statistical Significance ◽  
Cancer Center ◽  
Double Blind ◽  
Group 4 ◽  
Community Clinical Oncology Program ◽  
Delayed Nausea ◽  
Group 3 ◽  
Group 2 ◽  
Mean Differences ◽  
Group 1

Purpose We conducted a double-blind randomized clinical trial of the following four regimens for controlling delayed nausea (DN): group 1: palonosetron + dexamethasone on day 1 with prochlorperazine on days 2 and 3; group 2: granisetron + dexamethasone on day 1 with prochlorperazine on days 2 and 3; group 3: aprepitant + palonosetron + dexamethasone on day 1 with aprepitant + dexamethasone on days 2 and 3; and group 4: palonosetron + dexamethasone on day 1 with prochlorperazine + dexamethasone on days 2 and 3. Patients and Methods Chemotherapy-naive patients received doxorubicin, epirubicin, cisplatin, carboplatin, or oxaliplatin. The primary end point was average nausea assessed four times daily on days 2 and 3. Primary analyses were whether nausea control would be improved by using palonosetron versus granisetron on day 1 (group 1 v group 2); by adding dexamethasone on days 2 and 3 (group 1 v group 4); and by using aprepitant versus prochlorperazine (group 3 v group 4). Statistical significance was set at P = .017. Results Two hundred thirty-four, 234, 241, and 235 evaluable patients were accrued to groups 1, 2, 3, and 4, respectively. Adjusted mean differences for the three planned analyses were as follows: palonosetron versus granisetron: −0.01 (95% CI, −0.23 to 0.20; P = .72); adding dexamethasone on days 2 and 3: 0.20 (95% CI, −0.02 to 0.41; P = .01); and using aprepitant versus prochlorperazine: −0.03 (95% CI, −0.24 to 0.19; P = .56). Conclusion The addition of dexamethasone on days 2 and 3 reduced DN. Palonosetron and granisetron have similar effects on DN. The beneficial effect of adding aprepitant for control of DN was the same as adding prochlorperazine.

scholarly journals Soil diversity and properties in mountainous subtropical areas, in Sierra Sur de Oaxaca, Mexico

2006 ◽  
Vol 86 (1) ◽  
pp. 61-76 ◽  
Author(s):  
N. E. García Calderón ◽  
A. Ibáñez Huerta ◽  
G. Alvarez Arteaga ◽  
P. V. Krasilnikov ◽  
A. Hernández Jiménez
Keyword(s):  
Mass Movement ◽  
Clay Fraction ◽  
Chemical Properties ◽  
Mineralogical Composition ◽  
Parent Material ◽  
Soil Types ◽  
Soil Diversity ◽  
Parent Materials ◽  
Soil Groups ◽  
And Chemical Properties

Agroforestry is a new practice of sustainable soil use in the mountainous Sierra Sur de Oaxaca area of Mexico. Coffee is also a common cash crop grown in the region. The objective of this study was to investigate the pedodiversity in the area. Soil development is very complex, and is influenced by slope parameters and parent materials. Several soil groups are found in the area investigated: Alisols, Umbrisols, and Cambisols. Morphology, chemical properties, and mineralogical composition of the clay fraction of these soils were studied. The soils vary in the extent of weathering, morphology, and chemical properties, which are important to farming in the area. Most of the soils have heterogeneous parent material. The distribution of major soil types of the area is related to mass movement along the slopes, both past and present. The studied soils represent a chronosequence from unleached and unweathered Cambisols to Alisols, characterized by strong clay illuviation and dominance of kaolinite and gibbsite in clay fraction. A mosaic of landslides and gullies of various ages, formed by catastrophic events such as earthquakes and hurricanes, form the pedodiversity of the area studied. Key words: Landslides, chronosequence, pedodiversity, Cambisols, Umbrisols, Alisols

Geochemical Evidence of Saharan Dust Parent Material for Soils Developed on Quaternary Limestones of Caribbean and Western Atlantic Islands

1990 ◽  
Vol 33 (2) ◽  
pp. 157-177 ◽  
Author(s):  
Daniel R. Muhs ◽  
Charles A. Bush ◽  
Kathleen C. Stewart ◽  
Tracy R. Rowland ◽  
Russell C. Crittenden
Keyword(s):  
Volcanic Ash ◽  
Florida Keys ◽  
External Source ◽  
Parent Material ◽  
Saharan Dust ◽  
Caribbean Island ◽  
Trade Winds ◽  
Western Atlantic ◽  
Parent Materials ◽  
External Sources

AbstractMost previous workers have regarded the insoluble residues of high-purity Quaternary limestones (coral reefs and oolites) as the most important parent material for well-developed, clay-rich soils on Caribbean and western Atlantic islands, but this genetic mechanism requires unreasonable amounts of limestone solution in Quaternary time. Other possible parent materials from external sources are volcanic ash from the Lesser Antilles island arc and Saharan dust carried across the Atlantic Ocean on the northeast trade winds. Soils on Quaternary coral terraces and carbonate eolianites on Barbados, Jamaica, the Florida Keys (United States), and New Providence Island (Bahamas) were studied to determine which, if either, external source was important. Caribbean volcanic ashes and Saharan dust can be clearly distinguished using ratios of relatively immobile elements (Al2O3/TiO2, Ti/Y, Ti/Zr, and Ti/Th). Comparison of these ratios in 25 soils, where estimated ages range from 125,000 to about 870,000 yr, shows that Saharan dust is the most important parent material for soils on all islands. These results indicate that the northeast trade winds have been an important component of the regional climatology for much of the Quaterary. Saharan dust may also be an important parent material for Caribbean island bauxites of much greater age.

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