scholarly journals Effect of different pH levels on adsorption and desorption of Pb in contrasting parent materials of south eastern agro climatic zone of Nigeria

2021 ◽  
pp. 102-108
Author(s):  
Nkwopara U. N ◽  
Onwudike S.U ◽  
Ihem E.E ◽  
Osisi A.F ◽  
Egboka N.T
Keyword(s):  
Organic Matter ◽  
Soil Ph ◽  
Coastal Plain ◽  
Significant Positive Correlation ◽  
Olivine Basalt ◽  
The Other ◽  
Solution Ph ◽  
Adsorption And Desorption ◽  
Parent Materials ◽  
Positive Correlation

Lead adsorption and desorption at different pH levels in acid soils of diverse parent materials were evaluated. The soil samples were collected from soils underlain by olivine basalt (Ikom), coastal plain sands (Ihiagwa) and false bedded sandstone (Ishiagu). The collected samples were air -dried, crushed, sieved with a 2 mm sieve and analyzed in the laboratory. The adsorption of lead (Pb) increased with increasing solution pH. At pH 3, 4 and 6, the adsorption of Pb was higher in false bedded sandstone than the other soils. At pH 5, adsorption of Pb was higher in olivine basalt than the other soils. Except at pH 3, desorption of Pb was higher in coastal plain sands than the other soils. At the same time it was lower in false bedded sand stone than the other soils at all pH. At pH 5, adsorption of Pb had a significant positive correlation with organic matter (r =0.774481, p≤ 0.05), while at pH 6, it had a significant positive correlation with soil pH (r =0.738401, p ≤ 0.05). Organic matter and soil pH are the most critical soil properties affecting adsorption-desorption of Pb on these soils.

scholarly journals European survey shows poor association between soil organic matter and crop yields

2020 ◽  
Vol 118 (3) ◽  
pp. 325-334
Author(s):  
Wytse J. Vonk ◽  
Martin K. van Ittersum ◽  
Pytrik Reidsma ◽  
Laura Zavattaro ◽  
Luca Bechini ◽  
...  
Keyword(s):  
Organic Matter ◽  
Soil Organic Matter ◽  
Sugar Beet ◽  
Significant Positive Correlation ◽  
Agricultural Land ◽  
Crop Yields ◽  
Carbon Sink ◽  
Significant Negative Correlation ◽  
Positive Correlation ◽  
Farm Survey

AbstractA number of policies proposed to increase soil organic matter (SOM) content in agricultural land as a carbon sink and to enhance soil fertility. Relations between SOM content and crop yields however remain uncertain. In a recent farm survey across six European countries, farmers reported both their crop yields and their SOM content. For four widely grown crops (wheat, grain maize, sugar beet and potato), correlations were explored between reported crop yields and SOM content (N = 1264). To explain observed variability, climate, soil texture, slope, tillage intensity, fertilisation and irrigation were added as co-variables in a linear regression model. No consistent correlations were observed for any of the crop types. For wheat, a significant positive correlation (p < 0.05) was observed between SOM and crop yields in the Continental climate, with yields being on average 263 ± 4 (95% CI) kg ha−1 higher on soils with one percentage point more SOM. In the Atlantic climate, a significant negative correlation was observed for wheat, with yields being on average 75 ± 2 (95%CI) kg ha−1 lower on soils with one percentage point more SOM (p < 0.05). For sugar beet, a significant positive correlation (p < 0.05) between SOM and crop yields was suggested for all climate zones, but this depended on a number of relatively low yield observations. For potatoes and maize, no significant correlations were observed between SOM content and crop yields. These findings indicate the need for a diversified strategy across soil types, crops and climates when seeking farmers’ support to increase SOM.

Morpho-Biochemical Characteristics of Brinjal Germplasms Affect the Abundance And Infestation of Jassid

2021 ◽  
Vol 19 (1) ◽  
pp. 81-91
Author(s):  
F Yasmin ◽  
MR Amin ◽  
M Afroz ◽  
MAH Swapon ◽  
MM Hossain
Keyword(s):  
Protein Content ◽  
Chlorophyll Content ◽  
Negative Correlation ◽  
Significant Positive Correlation ◽  
Significant Negative Correlation ◽  
Reducing Sugar ◽  
Total Sugar ◽  
The Other ◽  
Biochemical Characteristics ◽  
Positive Correlation

The tropical vegetable, brinjal is cultivated throughout the year in Bangladesh but the crop is infested by a number of insects including jassid. This study investigated the effects of different biophysical and biochemical characteristics of twelve brinjal germplasms on the abundance and infestation of jassid. The experiment was conducted during September 2018 to March 2019 in Gazipur, Bangladesh with twelve brinjal germplasms namely BD-7320, BD-7328, BD-9952, BD-10154, BD-10158, BARI Begun-1, BARI Begun-4, BARI Begun-5, BARI Begun- 6, BARI Begun-7, BARI Begun-8 and BARI Begun-9. The incidence of jassid was recorded from 3rd December to 26th March, and the lowest population was found on BARI Begun- 6. Among the biophysical traits, plant height, number of branch and leaf per plant, and leaf area exerted significant positive correlation; whereas trichome on lower and upper surfaces of leaf, spine per stem and leaf showed significant negative correlation with the abundance of jassid. On the other hand, moisture, reducing sugar, total sugar and protein content of the leaves and fruits, chlorophyll content of the leaves exerts significant positive correlation but ash and pH contents of the leaves and fruits were negatively correlated with the abundance of jassid. Jassids showed the lowest level of leaf infestation on BARI Begun-6, which could be for further analysis to develop jassid resistant brinjal. SAARC J. Agric., 19(1): 81-91 (2021)

scholarly journals Efektivitas Investasi dan Pembiayaan Internal: Fenomena Manajer Terlalu Percaya Diri di Pasar Modal Indonesia

2021 ◽  
Vol 3 (2) ◽  
pp. 115-125
Author(s):  
Deni Ramdani
Keyword(s):  
Significant Positive Correlation ◽  
Stock Exchange ◽  
Dual Role ◽  
The Other ◽  
Investment Efficiency ◽  
Positive Correlation ◽  
Other Hand ◽  
Internal Financing ◽  
Internal Funding

Overconfident managers create biases that make them overvalue their company and its investments. This study takes a sample of companies that are listed in the Indonesia Stock Exchange, for the years 2013-2017. Companies that are listed on the LQ 45 index have high liquidity so that the stock is active so it doesn't interfere with the accuracy of the research being carried out. The results showed that internal funding has a significant posi-tive relationship with company investment. This shows that the more internal financing, the greater the scale of the investment the company will make. Internal financing and overinvestment have a significant positive correlation. So that companies tend to over-invest. Internal finance has a dual role to play in investment. One side of the bias to im-prove investment efficiency by increasing the scale of investment and reducing the scale of investment, on the other hand it can cause excessive investment.DOI: https://doi.org/10.26905/afr.v3i2.3834

Water repellency of post-boggy soils with a various content of organic matter

Biologia ◽  
2009 ◽  
Vol 64 (3) ◽  
Author(s):  
Andrzej Lachacz ◽  
Monika Nitkiewicz ◽  
Barbara Kalisz
Keyword(s):  
Organic Matter ◽  
Organic Carbon ◽  
Significant Positive Correlation ◽  
C:N Ratio ◽  
Organic Matter Content ◽  
Water Repellency ◽  
Matter Content ◽  
Organic Soils ◽  
Mineral Matter ◽  
Positive Correlation

AbstractThe objective of this study was to estimate the water repellency of post-boggy soils in north-eastern Poland. Potential water repellency was determined based on the water drop penetration time (WDPT) test and the molarity of an ethanol droplet (MED) test. A total of 276 soil samples with a varied organic carbon (OC) content, ranging from trace amounts in sandy subsoils to 44.4% in organic soils, were analyzed. The investigated material represents peat-muck soils (Eutri-Sapric Histsols) and muck-like soils (Arenic Gleysols, Areni-Humic Gleysols, Gleyic Arenosols). The mineral matter of the analyzed soils comprised loose sand. The obtained results indicate that peat soil formations are marked by higher potential water repellency than muck soil formations. The highest WDPT values (16 390 s) were reported in respect of an alder peat sample with 41.9% OC content, collected at a depth of 55–60 cm. In the group of muck soils, a sample with 36.7% OC content, collected at a depth of 15–20 cm, was marked by the highest water repellency (WDPT 10 492 s). The water repellency of the studied soils is dependent on organic matter content, and it is manifested only when organic matter content is higher than 20%. Soils with OC content of up to 12% show low water repellency or are hydrophilic. Organic soil formations (>12% OC) are characterized by a varied degree of water repellency, but WDPT values in excess of 2000 s are reported only in respect of soils containing more than 35% OC. A significant positive correlation between the content of organic matter, organic carbon, total nitrogen and water repellency was observed in the entire studied population (n = 276). A significant positive correlation was also found between WDPT values and the C:N ratio, while a significant negative correlation was reported in respect of $$ pH_{H_2 O} $$.

The composition of whole casein from the milk of Ayrshire cows

1977 ◽  
Vol 44 (3) ◽  
pp. 447-454 ◽  
Author(s):  
D. T. Davies ◽  
A. J. R. Law
Keyword(s):  
Significant Positive Correlation ◽  
The Other ◽  
Percentage Composition ◽  
Positive Correlation ◽  
Stage Of Lactation ◽  
The Individual

SummaryThe composition of whole casein of 5 herd-bulk and 42 individual-cow milks from a single herd of Ayrshire cows has been determined. The percentage composition of the herd-bulk samples varied relatively little over a period of more than a year with the whole casein consisting on average of 38·4 % αs1,0-casein, 36·5 % β-casein, 12·5 % κ-casein, 10·5 % minor αs-caseins and 2·1 % γ-casein. For the individual-cow samples from mid-lactation, casein composition also was relatively constant, but in early and late lactation composition varied more with the relative amount of β-casein often being lower and those of κ- and γ-caseins often higher than in mid-lactation, these differences tending to be more marked in samples from older cows. Stage of lactation appeared to have little effect on the relative amounts of αs1,0-and minor αs-caseins.The concentrations of all casein fractions were significantly positively correlated (P < 0·001) with the concentration of whole casein in the milk. Also, there were significant negative correlations (P < 0·001) between the percentages of whole casein present as β- and κ-caseins, β- and γ-caseins and minor αs- and γ-caseins, and a significant positive correlation (P < 0·001) between the relative amounts of κ- and γ-caseins. The relative amount of the major αs1,0-casein fraction, however, was not closely related to those of any of the other fractions.Generally, milks with high lactose and low Na values yielded casein which was comparatively rich in β-casein and comparatively poor in κ- and γ-caseins.

Fur increases the parasite drag for flying bats

1995 ◽  
Vol 73 (5) ◽  
pp. 837-842 ◽  
Author(s):  
Z. Hassanloo ◽  
M. B. Fenton ◽  
J. D. DeLaurier ◽  
J. L. Eger
Keyword(s):  
Significant Positive Correlation ◽  
The Other ◽  
Positive Correlation ◽  
Aspect Ratios ◽  
Significant Tendency

We measured the drag (in grams) generated by air flowing at 5.02 m/s over blank plates and test plates to which bat skin and fur was glued, comparing drag values when air flowed with and against the "set" of the fur. Our samples included 37 specimens representing 27 species. There was a significant positive correlation between fur length and drag and significantly higher drag values when air flowed against rather than with the set of the fur. We found a significant tendency for bats with higher aspect ratios and higher wing loadings to have shorter fur, and the data from a naked bat (Cheiromeles torquatus) show that from an aerodynamic standpoint, bats would be better without fur. We conclude that the other benefits of fur, such as those relating to thermoregulation, communication, and crypsis, outweigh the costs of the drag it generates.

Effect of soil pH and organic matter on the adsorption and desorption of pentachlorophenol

2017 ◽  
Vol 25 (6) ◽  
pp. 5269-5279 ◽  
Author(s):  
Shui-Wen Chang Chien ◽  
Shou-Hung Chen ◽  
Chi-Jui Li
Keyword(s):  
Organic Matter ◽  
Soil Ph ◽  
Adsorption And Desorption

The Impact of Organizational Justice on Climate and Trust in High Schools

2009 ◽  
Vol 19 (4) ◽  
pp. 382-405 ◽  
Author(s):  
Michael Dipaola ◽  
Stephanie Guy
Keyword(s):  
High Schools ◽  
School Climate ◽  
Organizational Justice ◽  
Significant Positive Correlation ◽  
The Other ◽  
Independent Effect ◽  
Faculty Trust ◽  
Positive Correlation ◽  
Collegial Leadership ◽  
The Impact

In the private sector, organizational justice has consistently demonstrated a strong correlation with trust in management, employee commitment, and performance. The purpose of this study was to investigate whether organizational justice has a similar relationship with social processes in the educational arena. This study examined the relationship between organizational justice and school climate and sought to replicate earlier findings of a significant link between perceptions of justice and faculty trust in schools at a different level. In the representative sample of 36 high schools, a significant positive relationship was found between organizational justice and school climate. Additional analysis revealed a significant positive correlation between justice and each school climate dimension: collegial leadership, teacher professionalism, academic press, and community engagement. When regressed with the other climate dimensions, collegial leadership alone demonstrated a significant independent effect on organizational justice. A significant positive correlation was also found between organizational justice and all three faculty trust dimensions: trust in principal, trust in colleagues, and trust in clients. However, only trust in the principal demonstrated a significant and independent effect on organizational justice when regressed with the other trust dimensions.

Concentration of calcium, zinc, magnesium, potassium and sodium in the bovine cervical mucus during normal oestrus and oestrus induced by progesterone and/or PGF2α

2002 ◽  
Vol 14 (7) ◽  
pp. 427 ◽  
Author(s):  
T. Tsiligianni ◽  
A. Karagiannidis ◽  
N. Roubies ◽  
P. Saratsis ◽  
P. Brikas
Keyword(s):  
Negative Correlation ◽  
Significant Positive Correlation ◽  
Significant Negative Correlation ◽  
Cervical Mucus ◽  
The Other ◽  
Positive Correlation ◽  
Friesian Cows

Ninety-two healthy Friesian cows were used to determine the concentration of calcium (Ca), zinc (Zn), magnesium (Mg), potassium (K) and sodium (Na) in bovine cervical mucus and to compare these concentrations in cervical mucus collected during spontaneous and induced oestrus. Cows were assigned to four groups: (1) no treatment (2) PRID for 12 days plus pregnant mare's serum gonadotrophin (PMSG; 1000 IU, i.m.) at the removal of the PRID (3) PGF2α , two doses (6 mg, i.m.) 11 days apart, and (4) PRID for 7 days plus one dose of PGF2α (6 mg, i.m.) 24 h before removal of the PRID. The cows of the three induced-oestrus groups received two artificial inseminations (AI), whereas those in the spontaneous-oestrus group received only one. Cervical mucus samples were collected from all cows 5 to 30 min before the first AI. The results of this study can be summarized as follows: (1) viscosity was significantly lower (P<0.001) and crystallization was significantly (P<0.001) higher in the cervical mucus of cows in the spontaneous-oestrus group compared with cows in the induced-oestrus groups; (2)�Na concentration was similar in all groups; (3) concentration of all the other elements in the spontaneous-oestrus group was significantly lower (P<0.05) than in the induced-oestrus groups; (4) there was significant positive correlation (P<0.001) between viscosity and all elements, and significant negative correlation (P<0.05–P<0.001) between crystallization and all elements.

scholarly journals Samvariation mellan systematiska räkningar och spontan rapportering av rastande vadare i Getteröns naturreservat

Ornis Svecica ◽  
2021 ◽  
Vol 31 ◽  
pp. 34-43
Author(s):  
Reino Andersson
Keyword(s):  
Quantitative Data ◽  
Significant Positive Correlation ◽  
Spontaneous Reporting ◽  
Nature Reserve ◽  
The Other ◽  
Autumn Migration ◽  
Positive Correlation ◽  
Calidris Alpina ◽  
Other Hand

This paper is an attempt to describe how strong the covariation is between systematic counts and spontaneous reporting of staging waders at the Getterön Nature Reserve in southwestern Sweden. The material is based on systematic and spontaneous observations of twelve species of waders, made on the same days during the autumn migration in July–October 2010–2019. There is a significant positive correlation between the two methods for nine of twelve species. However, there is a large variation in the strength of the correlations, with the strongest correlation seen for Dunlin Calidris alpina. The Wood Sandpiper Tringa glareola, Green Sandpiper Tringa ochropus, and Little Stint Calidris minuta, on the other hand, show no significant correlations. This shows the difficulties in evaluating quantitative data of the wader occurrence at stopover areas such as Getterön. The variation in correlation between count methods between different species entails an uncertainty, which is probably due to low reliability in the spontaneous reporting. Thus, in the case of studies of staging waders based solely on spontaneous data, caution should be exercised.

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