scholarly journals Iron oxides and organic matter on soil phosphorus availability

2016 ◽  
Vol 40 (4) ◽  
pp. 369-379 ◽  
Author(s):  
Jessé Rodrigo Fink ◽  
Alberto Vasconcellos Inda ◽  
Tales Tiecher ◽  
Vidal Barrón
Keyword(s):  
Organic Matter ◽  
Iron Oxides ◽  
Soil Phosphorus ◽  
Phosphorus Availability ◽  
Phosphorus Sorption ◽  
Effective Strategies ◽  
Phosphorus Sorption Capacity ◽  
Soil Components ◽  
Relationship Of ◽  
The Relationship

ABSTRACT Continuous crop expansion has led to a growing demand for phosphate fertilizers. A sound knowledge of the dynamics of phosphorus, and its interaction with iron oxides and organic matter, can be useful to develop effective strategies for sustainable management, especially in a scenario of increasing shortage of mineral phosphate resources. In this paper, we review the relationship of phosphate to iron oxides and organic matter, and its effect on phosphorus availability. Crops typically obtain phosphate from weathered minerals and dissolved fertilizers. However, the amount of phosphorus present in the soil solution depends on the extent to which it is adsorbed or desorbed by iron oxides, which may be influenced by interactions with organic matter. Therefore, systems for fertilizer recomendation based on methodologies considering interactions between soil components such as oxides and organic matter, and the phosphorus sorption capacity resulting from such interactions (e.g. residual P analysis), may be more reliable to ensure efficient, rational use of phosphate.

Commentary on Chaplain-Physician Interactions From the Chaplain’s Perspective: A Mixed Method Analysis

2021 ◽  
pp. 104990912110030
Author(s):  
Rev George Handzo ◽  
Rev Brian Hughes
Keyword(s):  
Best Practices ◽  
Health System ◽  
Patient Care ◽  
Health Systems ◽  
Mixed Method ◽  
Effective Strategies ◽  
Optimal Patient Care ◽  
Relationship Of ◽  
The Relationship ◽  
Method Analysis

Gomez and her colleagues have presented a helpful study of the relationship of the chaplains in her health system to physicians which highlights several barriers to a well-integrated relationship and thus to more optimal patient care. We have seen these same barriers as we have consulted with health systems nationally and have also identified many best practices that mediate or even eliminate many of these barriers. This commentary describes some of what we have seen as chaplain-generated causes of those barriers and effective strategies that have been employed to overcome them. We also provide some resources for chaplains who wish to institute some of these best practices themselves.

scholarly journals Fractionation of Heavy Metals in Multi-Contaminated Soil Treated with Biochar Using the Sequential Extraction Procedure

Biomolecules ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 448
Author(s):  
Mahrous Awad ◽  
Zhongzhen Liu ◽  
Milan Skalicky ◽  
Eldessoky S. Dessoky ◽  
Marian Brestic ◽  
...  
Keyword(s):  
Heavy Metals ◽  
Organic Matter ◽  
Soil Organic Matter ◽  
Soil Ph ◽  
Contaminated Soil ◽  
Contaminated Soils ◽  
Extraction Procedure ◽  
Sequential Fractionation ◽  
Relationship Of ◽  
The Relationship

Heavy metals (HMs) toxicity represents a global problem depending on the soil environment’s geochemical forms. Biochar addition safely reduces HMs mobile forms, thus, reducing their toxicity to plants. While several studies have shown that biochar could significantly stabilize HMs in contaminated soils, the study of the relationship of soil properties to potential mechanisms still needs further clarification; hence the importance of assessing a naturally contaminated soil amended, in this case with Paulownia biochar (PB) and Bamboo biochar (BB) to fractionate Pb, Cd, Zn, and Cu using short sequential fractionation plans. The relationship of soil pH and organic matter and its effect on the redistribution of these metals were estimated. The results indicated that the acid-soluble metals decreased while the fraction bound to organic matter increased compared to untreated pots. The increase in the organic matter metal-bound was mostly at the expense of the decrease in the acid extractable and Fe/Mn bound ones. The highest application of PB increased the organically bound fraction of Pb, Cd, Zn, and Cu (62, 61, 34, and 61%, respectively), while the BB increased them (61, 49, 42, and 22%, respectively) over the control. Meanwhile, Fe/Mn oxides bound represents the large portion associated with zinc and copper. Concerning soil organic matter (SOM) and soil pH, as potential tools to reduce the risk of the target metals, a significant positive correlation was observed with acid-soluble extractable metal, while a negative correlation was obtained with organic matter-bound metal. The principal component analysis (PCA) shows that the total variance represents 89.7% for the TCPL-extractable and HMs forms and their relation to pH and SOM, which confirms the positive effect of the pH and SOM under PB and BB treatments on reducing the risk of the studied metals. The mobility and bioavailability of these metals and their geochemical forms widely varied according to pH, soil organic matter, biochar types, and application rates. As an environmentally friendly and economical material, biochar emphasizes its importance as a tool that makes the soil more suitable for safe cultivation in the short term and its long-term sustainability. This study proves that it reduces the mobility of HMs, their environmental risks and contributes to food safety. It also confirms that performing more controlled experiments, such as a pot, is a disciplined and effective way to assess the suitability of different types of biochar as soil modifications to restore HMs contaminated soil via controlling the mobilization of these minerals.

THE INFLUENCE OF SOME PHYSICAL AND CHEMICAL PROPERTIES ON SOIL AGGREGATION AND RESPONSE TO VAMA

1966 ◽  
Vol 46 (2) ◽  
pp. 155-160 ◽  
Author(s):  
G. R. Saini ◽  
A. A. MacLean ◽  
J. J. Doyle
Keyword(s):  
Organic Matter ◽  
Soil Properties ◽  
Chemical Properties ◽  
Correlation Coefficients ◽  
Multiple Correlation Coefficient ◽  
Mean Weight Diameter ◽  
The Mean ◽  
Relationship Of ◽  
Physical And Chemical ◽  
The Relationship

The relationship of the mean weight diameter of water-stable aggregates to certain soil properties (clay, organic matter, free iron, free aluminum, and polysaccharide contents) and the relationship of the increase in aggregation caused by VAMA to the same properties of 24 New Brunswick soils were evaluated by correlation and regression analyses.Simple correlation coefficients relating aggregation to soil properties indicated that organic matter (r = 0.627), polysaccharides (r = 0.602), and aluminum (r = 0.679) were the most important factors. However, when the influence of each factor was separated by partial correlation, the coefficients were not significant. On the other hand, the combined effects of all factors as indicated by the multiple correlation coefficient (r = 0.743) was significant at the 1% level. The effect of the same soil properties on response to VAMA, as shown by increase in mean weight diameter, indicated that clay exerted the greatest influence. The relationship with other factors was nonsignificant.

Life Stress and Performance Impairment: The Role of Off-Task Thinking

1995 ◽  
Vol 39 (13) ◽  
pp. 873-877
Author(s):  
Kitty Klein
Keyword(s):  
Life Stress ◽  
Poor Performance ◽  
Personality Variables ◽  
Mediating Role ◽  
Effective Strategies ◽  
Performance Impairment ◽  
Verbal Problem ◽  
And Performance ◽  
Relationship Of ◽  
The Relationship

In previous research (Baradell & Klein, 1993; Klein & Barnes, 1994) self-focused attention has moderated the relationship of life stress and verbal problem solving. Stressed individuals highly aware of internal bodily changes made the most errors and used the least effective strategies. How life stress affects information processing on such tasks has not been investigated. In theories (e. g. Humphreys & Revelle, 1984; Eysenck, 1992) that relate personality variables to cognitive processes, off-task thinking is presumed to mediate the relationship between individual differences and performance. In the present study, 35 students who varied in life stress and self-focus solved complex verbal analogies. The results indicated that high levels of stress and self-focus were related to off-task thinking and that off-task thinking was negatively related to performance. However, regression analyses did not support a mediating role for off-task thinking. Rather, off-task thinking may result from poor performance, rather than vice-versa as is assumed in current models.

scholarly journals Organic matter and mineralization of river waters in mountains of Russia and adjacent countries

2019 ◽  
pp. 99-106
Author(s):  
M. P. Smirnov
Keyword(s):  
Organic Matter ◽  
Experimental Studies ◽  
The Arctic ◽  
Mountain Rivers ◽  
River Waters ◽  
Taiga Forest ◽  
Salinity Water ◽  
Cis Countries ◽  
Relationship Of ◽  
The Relationship

The article examines general regularities of the formation of dissolved organic matter (DOM), salinity (∑), the acid-alkaline indicators (pH) river waters in the mountains with various types of altitudinal zonation in Russia and CIS countries. The analysis is based on the results of many years of experimental studies in the network of the Roshydromet. The reaction of water of rivers in a southerly direction in accordance with changes in landscape-geochemical conditions are sequentially changed from acidic in the tundra of the Arctic to neutral in the tundra and taiga, slightly alkaline in forest-meadow and alkaline in a desert and subtropical mountains. The average annual salinity water of the mountain rivers in two Northern types of vertical zones is 42 and 74 mg/l, in two Southern types – 140 and 450 mg/l. The average annual values of permanganate (PO) and bichromate (BO) oxidation, and color of river water in xerophytic desert-subtropical mountains are small (3 and 7), and increase to medium and slightly increased grades into humid tundra and taiga, tundra of the Arctic, and the forest meadow mountains (7–8 and 13–18 mg O/l). Relationships PO:BO change from 62% in the tundra of the Arctic up to 50%, 41% and 35% in the tundra and taiga, forest-meadow and desert-subtropical mountains. The content of humic (HA) and fulvic (FA) acids is also maximum in two Northern types of vertical zones (0.224 and 1.80 mg/l) and decreases in the two Southern types to 0.013 and 0.067, 0.373 and 0.637 mg/l. The relationship of contents of HA and FA decreases to the South in forest-grassland and desert-subtropical mountains in 1.3 and 3.7 times.

Pronamide Phytotoxicity in Ten Wisconsin Soils

Weed Science ◽  
1980 ◽  
Vol 28 (4) ◽  
pp. 429-432 ◽  
Author(s):  
T. E. Dutt ◽  
R. G. Harvey
Keyword(s):  
Organic Matter ◽  
Chemical Properties ◽  
Clay Content ◽  
Exchange Capacity ◽  
Fresh Weight ◽  
Relationship Of ◽  
Physical And Chemical ◽  
Mg Content ◽  
The Relationship ◽  
And Chemical Properties

Pronamide [3,5-dichloro-(N-1, 1-dimethyl-2-propynyl) benzamide] phytotoxicity was compared in 10 Wisconsin soils and the relationship of activity to soil physical and chemical properties appraised. Twelve soil properties were measured and correlated with pronamide I50(50% fresh weight inhibition) values using oats (Avena sativaL. ‘Portal’) as the indicator plant in bioassays conducted under greenhouse conditions. Organic matter was the soil variable most inversely correlated with pronamide phytotoxicity. Cation exchange capacity, field moisture capacity, and Mg content were also inversely correlated with pronamide phytotoxicity, but probably reflect changes in soil organic matter levels. Clay content did not significantly affect pronamide phytotoxicity.

scholarly journals Boron sorption in soils and its extractability by soil tests (Mehlich 3, ammonium acetate and water extraction)

2009 ◽  
Vol 55 (No. 1) ◽  
pp. 42-49 ◽  
Author(s):  
J. Matula
Keyword(s):  
Organic Matter ◽  
Soil Organic Matter ◽  
Ammonium Acetate ◽  
Ph Value ◽  
Exchange Capacity ◽  
Soil Test ◽  
Soil Tests ◽  
Background Data ◽  
Relationship Of ◽  
The Relationship

The aim of the paper was to contribute to the acquisition of background data for the specification of safe boron levels in soils in relation to diagnostics by multi-nutrient soil tests and to CEC (cation exchange capacity) value of soil, pH and soil organic matter. The research was conducted on 24 soils. Sorption was determined after 97 days from the application of B at the rates of 0, 1, 2.5, 5 mg B/kg in H<sub>3</sub>BO<sub>3</sub>. The closest regression of B-sorption was with the CEC value of soil in NH<sub>4</sub>-acetate and water tests and it increased with the increasing application of B (regression at a rate of 5 ppm B; NH<sub>4</sub>-acetate: linear <I>R</I><sup = 0.632, polynomial 2<sup>nd</sup> <I>R</I><sup = 0.644; water: linear R<sup = 0.644, polynomial 2<sup>nd</sup> <I>R</I><sup = 0.599). No relationship was found in the Mehlich 3 test. Regressions of B sorption on pH value were substantially lower. The relationship of B sorption with soil organic matter was similar to CEC, but less close. In the NH<sub>4</sub>-acetate soil test, after the correction of CEC value of soil by pH deviations from the optimum, regression was improved (linear <I>R</I><sup = 0.821, polynomial 2<sup>nd</sup> <I>R</I><sup = 0.837).

scholarly journals Relationship of Work Context and Work Stress among Sonographers in Riyadh, KSA

2017 ◽  
Author(s):  
Uzma Zaidi ◽  
Lena F. Hammad ◽  
Salwa S. Awad ◽  
Safaa M. A. Elkholi ◽  
Hind D. Qasem
Keyword(s):  
Work Stress ◽  
Good Health ◽  
Strong Positive Correlation ◽  
Work Context ◽  
Effective Strategies ◽  
Significant Difference ◽  
Gender Based ◽  
Stress At Work ◽  
Relationship Of ◽  
The Relationship

Work context is essential to understand in relation to handle the stress at work that ultimately creates a feeling of satisfaction or dissatisfaction among health professionals. The current study was conducted to investigate the relationship of work context and work stress among sonographers (n=153) in Riyadh, Saudi Arabia. Additionally, the study provided a gender-based comparison of both variables among sonographers. Work context was measured by administering subscale of work context derived from Work Design Questionnaire. Whereas, work stress was measured by Job Stress Scale. In addition, relationship of lifestyle was explored with work context and work stress. Data was collected through survey research forms. Results revealed the significant relationship of work context and work stress (r=.251, p=.002). Among lifestyle variables, perceived good health (r= .214, p=.008) and sleep (r=.242. p=.003) were found positively related with satisfaction toward work. Whereas, the strong positive correlation was found between work context and frequency of physical activity (r=.255, p=.005). No significant difference was found among male and female sonographers. The findings of this study contributed to evaluating the working condition of sonographers in relation to work stress. Effective strategies for better working settings as well as strategies for achieving satisfaction in work will be discussed to enhance the performance of sonographers.

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