Dissolution of phosphate rock fertilisers in some soils of Okinawa, Japan

Soil Research ◽  
1999 ◽  
Vol 37 (1) ◽  
pp. 115 ◽  
Author(s):  
Daniel E. Dodor ◽  
Yoshihiro Tokashiki ◽  
Kazuhiro Oya ◽  
Moritaka Shimo
Keyword(s):  
South Africa ◽  
Regression Analysis ◽  
Regression Model ◽  
Soil Properties ◽  
Phosphate Rock ◽  
Soil Samples ◽  
Direct Application ◽  
Primary Concern ◽  
Rapid Estimation ◽  
Rate Of Dissolution

The ability of phosphate rock (PR) to dissolve rapidly in soil is a primary concern in its direct application as P fertiliser. The dissolution of 4 PR materials (Togo, South Africa, Florida, Morocco PRs) in 15 soil samples in Okinawa was investigated in a closed-incubation system for 7 days. The fertilisers were mixed with the soils at rates of addition of 600–1200 µg Ca/g soil. The extent and rate of dissolution of the PRs were determined by measuring the increase in extractable Ca of the fertilised soils compared with unfertilised soils, i.e. the delta Ca (ΔCa) technique. Generally, the amounts of dissolution of 3 of the PRs were very low (mean 6·7% for Togo PR, 13·6% for South Africa PR, and 20·8% for Florida PR). However, Morocco PR dissolved to an appreciable extent (mean 60·8%), suggesting that it can be an alternative P source, especially in the red and yellow soils of Okinawa. Soil properties identified as affecting dissolution were different for the different PRs. In order to predict the suitability of Morocco PR for Okinawan soils, the extent of its dissolution was related to soil properties in a multiple regression analysis. Results indicated that the best regression model for predicting the amount of dissolution was the combination of pH, Ca saturation, and Truog P (r2 = 0·55**). Measured values of percentage dissolution of Morocco PR were significantly correlated with calculated percentages (r = 0·844***), indicating that the equation obtained could offer a rapid estimation of amount of dissolution of Morocco PR in Okinawan soils.

scholarly journals Specification of the beechwood soil environment based on chosen soil properties, aiming at the Fageta paupera habitat

2011 ◽  
Vol 57 (No. 5) ◽  
pp. 185-191
Author(s):  
A. Kučera ◽  
K. Rejšek ◽  
P. Dundek ◽  
K. Marosz ◽  
P. Samec ◽  
...  
Keyword(s):  
Regression Analysis ◽  
Soil Properties ◽  
Chemical Properties ◽  
European Beech ◽  
Soil Samples ◽  
Soil Environment ◽  
Laboratory Assessment ◽  
Definition Of ◽  
Properties Of Soil ◽  
And Chemical Properties

ABSTRACT: This paper deals with a specific type of homogeneous beechwood called Fageta paupera. The aim is to acquire information about the heterogeneity of soil environment. As a material we used 20 research plots of semi-natural European beech stands, where the sampling of soil profile and the observation of floristic conditions were realized. Laboratory assessment of soil samples was focused on physicochemical and chemical properties of soil: pH/CaCl<sub>2</sub>, K<sup>+</sup>, Ca<sup>2+</sup>, Mg<sup>2+</sup>, CEC (T, S, V), C<sub>ox</sub>, N<sub>t</sub>, C/N, C-FA, C-HA, C-CHL, C-HA/FA. Data processing was done with the aim to discover a variability of soils, observing soil genetic horizons individually (H, A, B, C). Research plots were divided into biotopes with the cover of understory vegetation &lt; 15% and &gt; 15% (in accordance with the definition of Fageta paupera) and the variability of soil properties in each horizon for the two above-mentioned biotopes and furthermore for all plots together was investigated. Results show the highest variability of soil properties in the biotope of Fageta paupera, especially in its holorganic (H) and organomineral (A) horizons. Furthermore, regression analysis showed the strongest dependence of the variability of soil properties in the biotope of Fageta paupera.

scholarly journals Direct application of reactive phosphate rock on improving maize yield in tidal swampland

2021 ◽  
Vol 648 (1) ◽  
pp. 012175
Author(s):  
A F Siregar ◽  
Husnain ◽  
I W Suastika ◽  
N P S Ratmini ◽  
I A Sipahutar ◽  
...  
Keyword(s):  
Phosphate Rock ◽  
Maize Yield ◽  
Direct Application ◽  
Reactive Phosphate ◽  
Reactive Phosphate Rock

Correlation of pH on Soil Physicochemical Properties using Linear Regression Model for Spectral Data Analysis

2021 ◽  
Vol 10 (1) ◽  
pp. 3492-3500
Author(s):  
Vipin Y. Borole ◽  
◽  
Sonali B. Kulkarni ◽  
Keyword(s):  
Linear Regression ◽  
Plant Growth ◽  
Physicochemical Properties ◽  
Regression Model ◽  
Soil Properties ◽  
Spectral Data ◽  
Linear Regression Model ◽  
Soil Analysis ◽  
Soil Physicochemical Properties ◽  
Analytical Technique

Soil properties may be varied by spatially and temporally with different agricultural practices. An accurate and reliable soil properties assessment is challenging issue in soil analysis. The soil properties assessment is very important for understanding the soil properties, nutrient management, influence of fertilizers and relation between soil properties which are affecting the plant growth. Conventional laboratory methods used to analyses soil properties are generally impractical because they are time-consuming, expensive and sometimes imprecise. On other hand, Visible and infrared spectroscopy can effectively characterize soil. Spectroscopic measurements are rapid, precise and inexpensive. Soil spectroscopy has shown to be a fast, cost-effective, environmentally friendly, non-destructive, reproducible and repeatable analytical technique. In the present research, we use spectroscopy techniques for soil properties analysis. The spectra of agglomerated farming soils were acquired by the ASD Field spec 4 spectroradiometer. Different fertilizers treatment applied soil samples are collected in pre monsoon and post monsoon season for 2 year (4 season) for banana and cotton crops in the form of DS-I and DS-II respectively. The soil spectra of VNIR region were preprocessed to get pure spectra. Then process the acquired spectral data by statistical methods for quantitative analysis of soil properties. The detected soil properties were carbon, Nitrogen, soil organic matter, pH, phosphorus, potassium, moisture sand, silt and clay. Soil pH is most important chemical properties that describe the relative acidity or alkalinity of the soil. It directly effect on plant growth and other soil properties. The relationship between pH properties on soil physical and chemical parameters and their influence were analyses by using linear regression model and show the performance of regression model with R2 and RMSE. Keywords soil; physicochemical properties; spectroscopy; pH

EFFECTS OF LIME ON EXTRACTABLE ALUMINUM AND OTHER SOIL PROPERTIES AND ON BARLEY AND ALFALFA GROWN IN POT TESTS

1972 ◽  
Vol 52 (3) ◽  
pp. 427-438 ◽  
Author(s):  
A. J. MacLEAN ◽  
R. L. HALSTEAD ◽  
B. J. FINN
Keyword(s):  
Plant Growth ◽  
Soil Properties ◽  
Soil Ph ◽  
Acid Soil ◽  
Soil Samples ◽  
Neutral Salt ◽  
Incubation Experiment ◽  
Pot Experiments ◽  
P Content ◽  
Mn Content

Liming of six acid soil samples in an incubation experiment with rates to raise the soil pH to 6.0 or above eliminated Al soluble in 0.01 M CaCl2, reduced soluble Mn and Zn, increased NO3-N markedly, and at the highest pH increased the amounts of NaHCO3-soluble P in some of the soils. In corresponding pot experiments, liming increased the yield of alfalfa and in three of the soils the yield of barley also. Liming reduced the concentrations of the metals in the plants and at the highest pH tended to increase the P content of the plants. Liming to a pH of about 5.3 eliminated or greatly reduced soluble Al and the soils were base saturated as measured by the replacement of Al, Ca, and Mg by a neutral salt. There was some evidence that liming to reduce soluble Al and possibly Mn was beneficial for plant growth. Gypsum increased the concentrations of Al, Mn, and Zn in 0.01 M CaCl2 extracts of the soils whereas phosphate reduced them. The changes in the Mn content of the plants following these treatments were in agreement with the amounts of Mn in the CaCl2 extracts.

Wood Ash Improved Soil Properties and Crop Yield for Nine Years and Saved Fertilizer

2015 ◽  
Vol 7 (12) ◽  
pp. 72 ◽  
Author(s):  
Kabal S. Gill ◽  
Sukhdev S. Malhi ◽  
Newton Z. Lupwayi
Keyword(s):  
Soil Properties ◽  
Seed Yield ◽  
Crop Production ◽  
Soil Acidity ◽  
Crop Yields ◽  
Wood Ash ◽  
Soil Samples ◽  
Residual Effects ◽  
Contribution Margin ◽  
Seed Yields

<p>Wood ash may be used to mitigate soil acidity and improve crop production. We compared effects of wood ash and recommended fertilizers on soil properties of a Gray Luivsol, crop yields and contribution margins in southeast Peace, Alberta, Canada. The CHK (no fertilizer, inoculation or wood ash), FRT (recommended fertilizers or inoculation), ASH (wood ash rate to supply amounts of phosphorus equivalent to the FRT treatment); and ASH+N (same as ASH + N fertilizer or inoculation) treatments were applied in 2006 and 2007. Their effects were studied from 2006 to 2014. Wood ash had all the essential plant nutrients, except nitrogen. Soil samples collected in 2007, 2008 and 2013 had or tended to have higher pH, P, K, Ca, Ca:Mg ratio, S, Cu, Zn and B levels for the ASH and ASH+N treatments than the CHK and FRT treatments. In the 2006 and 2007, the seed yields were ASH+N &gt; FRT &gt; ASH &gt; CHK. The seed yields in 2008, 2010, 2012, 2013 and 2014 were greater from both the wood ash treatments than other treatments. Extra contribution margin from the ASH+N over the FRT treatment was $751/ha, i.e. $97 Mg<sup>-1</sup> of applied wood ash. Overall, wood ash reduced fertilizer expenditure and improved seed yield, contribution margin and soil properties, with residual effects observed up to seven years and likely for few more years.</p>

scholarly journals Prognosis of chronic lymphocytic leukemia: a multivariate regression analysis of 325 untreated patients

Blood ◽  
1987 ◽  
Vol 69 (3) ◽  
pp. 929-936 ◽  
Author(s):  
JS Lee ◽  
DO Dixon ◽  
HM Kantarjian ◽  
MJ Keating ◽  
M Talpaz
Keyword(s):  
Alkaline Phosphatase ◽  
Uric Acid ◽  
Regression Analysis ◽  
Lactate Dehydrogenase ◽  
Chronic Lymphocytic Leukemia ◽  
Regression Model ◽  
Multivariate Regression ◽  
Risk Groups ◽  
Multivariate Regression Analysis ◽  
Lymphocytic Leukemia

Three hundred twenty-five previously untreated patients with chronic lymphocytic leukemia were analyzed to identify significant prognostic factors for survival. Univariate analysis identified the following characteristics associated with survival: (1) clinical characteristics: age, race, sex, performance status, lymphadenopathy, and hepatosplenomegaly; (2) hematologic parameters: WBC count, absolute lymphocyte and granulocyte counts, hemoglobin level, and platelet count; and (3) biochemical parameters: serum albumin, calcium, uric acid, lactate dehydrogenase, alkaline phosphatase, BUN, and creatinine. Multivariate regression analysis in a randomly selected training subset of 217 patients demonstrated that the combination of uric acid, alkaline phosphatase, lactate dehydrogenase, external lymphadenopathy, and age had the strongest predictive relation to survival time. The resulting model was validated in the remaining independent subset of 108 patients and led to classification of patients into low, intermediate, and high-risk groups with five-year survival rates of 75%, 59%, and 14%, respectively, and with distinctively different annual mortality rates (P less than .01). Both the regression model and Rai staging were highly effective in identifying risk groups among the entire patient population (P less than 0.001). Overall the regression model was superior to Rai staging in defining prognostic risk groups. In addition, it was able to separate patients into significantly different risk categories within each Rai stage, thus improving on the prognostic prediction of individual patients with chronic lymphocytic leukemia.

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