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Chemical, physical, physiological and agronomic aspects of soil acidity and liming of 10 organic soils from South-West Quebec.Van Lierop, William J. C. M. January 1973 (has links)
No description available.
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Properties of clays and soils after acid treatment /Yeoh, Ngoh Sum. January 1979 (has links) (PDF)
Thesis (M.Ag.Sci. 1980) from the Department of Soil Science, University of Adelaide.
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Responses of accessions of Austrodanthonia spp. to factors associated with soil acidityIslam, Mohammed Anowarul. January 2002 (has links)
Thesis (Ph. D.)--University of Sydney, 2003. / Title from title screen (viewed Apr. 28, 2008). Submitted in fulfilment of the requirements for the degree of Doctor of Philosophy to the Dept. of Land, Water and Crop Sciences, Faculty of Agriculture, Food and Natural Resources. Degree awarded 2003; thesis submitted 2002. Includes bibliography. Also available in print form.
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Some aspects of buffering of acid soils of the Lower Fraser ValleyWiens, John H. January 1970 (has links)
A study was made to: i) determine the nature of acidity and buffering in acid soils of the Lower Fraser Valley of British Columbia, ii) evaluate and develop methods of predicting buffer capacities of these soils. Results of this study are described in a series of four papers, each describing different phases of this study.
The Woodruff and Shoemaker, McLean and Pratt buffer methods proved to be unsuitable for use with these soils when compared to Ca(OH)₂ titration because the buffer pH depression was too small per unit lime requirement and there was considerable scatter about the regression calibration lime.
Measurements of lime potential and corrected lime potential as well as pH were found to be significantly correlated with measures of exchangeable acidity but not with measures of pH-dependent acidity. The pH-dependent component of potential acidity was found to be highest for horizons highest in organic matter and in acid ammonium oxalate extractable Al and Fe.
Regression equations derived for predicting buffer capacities explained the largest degree of variation of titrable acidity in the pH ranges below pH 5 and above pH 6. The model developed, combining these equations for prediction of buffer capacities to selected end pH values predicted buffer capacities as determined by a Ca(OH)₂ titration reasonably well.
Comparison of NaOCl with H₂O₂ for oxidation of organic matter prior to acid ammonium oxalate extraction showed the former to be less destructive to sesquioxides, while at the same time as good or better for the oxidation of organic matter. Results of titrations of soils before and after oxalate extraction following treatment with NaOCl gave inconclusive results with respect to acidity due to the oxalate extractable component. This was due not to the method of removal of organic matter, however, but to uncertainties with respect to the nature of the exchange phase. / Land and Food Systems, Faculty of / Graduate
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Chemical, physical, physiological and agronomic aspects of soil acidity and liming of 10 organic soils from South-West Quebec.Van Lierop, William J. C. M. January 1973 (has links)
No description available.
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The Determination and Interpretation of Soil PH ValuesMcGeorge, W. T. 15 October 1944 (has links)
This item was digitized as part of the Million Books Project led by Carnegie Mellon University and supported by grants from the National Science Foundation (NSF). Cornell University coordinated the participation of land-grant and agricultural libraries in providing historical agricultural information for the digitization project; the University of Arizona Libraries, the College of Agriculture and Life Sciences, and the Office of Arid Lands Studies collaborated in the selection and provision of material for the digitization project.
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Liming requirement of selected Willamette Valley soilsPeterson, Paul William 01 September 1971 (has links)
There are two major problems associated with soil acidity and
lime response investigations:
A. Determining how much lime (100% "available" CaCO��� equivalent)
is required to raise a soil pH (or degree of acidity) from its
existing level to a specified level - presumably where need for
lime is eliminated.
B. Determining responses of different crops on different soils to
lime; and defining some chemical measurement of the soil that
will predict the response of a specified crop.
Investigations in this study were limited to the first problem.
Liming characteristics of 45 acid Willamette Valley soils, representing
the major agricultural soil associations, were determined by incubating
the soils with increments of CaCO���. The lime required to
bring the soils to the specified pH levels of 6.8, 6.4 and 6.0 varied
widely within the respective pH levels. Relationships between soils,
however, as determined by the value of the incubation curve slope
(meq. of CaCO��� /100g of soil required to raise soil pH by one unit),
were improved by grouping into related soils. Laboratory measurements
of other soil chemistry parameters were compared with
changes in pH to determine if a satisfactory quick laboratory procedure
could be developed to measure the incubation lime requirement
of soils with different chemical characteristics.
Measurements of soil pH were made by three different methods:
(1) in the supernatant of a 1:2 soil to water suspension; (2) in the
sedimented paste of the 1:2 soil to water suspension; and (3) in the
supernatant of a 1:2 soil to 1 N KCl suspension. Lime requirement
with a buffered solution was measured in limed and unlimed
soils by use of the SMP (Shoemaker, McLean, and Pratt) buffer
method. Soil samples treated with increments of lime were analyzed
for extractable Al and exchange acidity by titration and the unincubated
soils were analyzed for exchange acidity determined by subtracting
exchangeable bases from CEC measured at pH 7. 0 and pH 6. 0.
Results of the correlation analyses showed that the SMP buffer
method should prove useful for predicting the incubation lime requirement.
Correlation coefficients for these two values were .89, .90
and 86, respectively, to reach pH levels of 6.8, 6.4 and 6.0. Soil
pH measurements, extractable Al, and exchange acidity determinations
did not provide as good a basis for determining incubation lime requirements,
Regression equations were calculated for the SMP
buffer/incubation lime requirement relationships.
The purpose of this study was to identify the changes in soil
chemical measurements that take place with application of lime. No
attempt was made to determine whether a crop might respond to an
application of lime on an acid soil. The assumption was made that
yield could be related to specific pH or soil acidity levels that could
be measured in the laboratory. Therefore, the problem was approached
by studying procedures that might determine the application of lime
required to reach a specified pH or soil acidity measurement. It
anticipated that field trials for evaluating lime response will be
carried out in the future to evaluate the usefulness of the SMP buffer
method which showed promise in this regard. / Graduation date: 1972
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The use of gypsum and a coal desulfurization by-product to ameliorate subsoil acidity for alfalfa growthChessman, Dennis John 30 September 2004 (has links)
Acid soils limit the growth of aluminum-(Al) sensitive crops such as alfalfa (Medicago sativa L.). Management of acid subsoils can be difficult due to physical and economic constraints. Field experiments were conducted at two locations to evaluate the effectiveness of surface-applied gypsum and a flue gas desulfurization by-product for reducing the toxic effects of acid subsoils on alfalfa. The materials were applied at rates of 0, 5, 10, and 15 Mg ha-1. In addition, a glasshouse experiment was conducted that used 0, 5, and 10 Mg ha-1 of gypsum only. Field studies were concluded 41 and 45 months after treatment application at the two locations. No effect of material on alfalfa yield or tissue mineral concentration was observed. Also, rate did not affect yield. However, there were differences in plant tissue mineral concentration in several harvests that were related to rate. Soil was sampled periodically to 120 cm and indicated movement of Ca and S into the soil profile to depths of 60 and 120 cm, respectively. Subsoil pHH2O and pHCaCl2 were not affected by treatment. Extractable and exchangeable Al were not reduced by movement of Ca and S into the soil. In the glasshouse study, alfalfa yields and root growth were not affected by gypsum rate. As gypsum rate increased, plant tissue S increased, but K and Mg decreased. Alfalfa roots did not grow below 60 cm, even though there was indication of material movement to 90 cm in the soil. Although sulfur moved to 75 cm, no effect on soil Al was observed. Leachate collected from the bottoms of columns indicated that soil cations were leached as a result of gypsum application. Gypsum and the flue gas desulfurization by-product did not significantly affect the acid soils used in these studies or improve alfalfa growth.
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The use of gypsum and a coal desulfurization by-product to ameliorate subsoil acidity for alfalfa growthChessman, Dennis John 30 September 2004 (has links)
Acid soils limit the growth of aluminum-(Al) sensitive crops such as alfalfa (Medicago sativa L.). Management of acid subsoils can be difficult due to physical and economic constraints. Field experiments were conducted at two locations to evaluate the effectiveness of surface-applied gypsum and a flue gas desulfurization by-product for reducing the toxic effects of acid subsoils on alfalfa. The materials were applied at rates of 0, 5, 10, and 15 Mg ha-1. In addition, a glasshouse experiment was conducted that used 0, 5, and 10 Mg ha-1 of gypsum only. Field studies were concluded 41 and 45 months after treatment application at the two locations. No effect of material on alfalfa yield or tissue mineral concentration was observed. Also, rate did not affect yield. However, there were differences in plant tissue mineral concentration in several harvests that were related to rate. Soil was sampled periodically to 120 cm and indicated movement of Ca and S into the soil profile to depths of 60 and 120 cm, respectively. Subsoil pHH2O and pHCaCl2 were not affected by treatment. Extractable and exchangeable Al were not reduced by movement of Ca and S into the soil. In the glasshouse study, alfalfa yields and root growth were not affected by gypsum rate. As gypsum rate increased, plant tissue S increased, but K and Mg decreased. Alfalfa roots did not grow below 60 cm, even though there was indication of material movement to 90 cm in the soil. Although sulfur moved to 75 cm, no effect on soil Al was observed. Leachate collected from the bottoms of columns indicated that soil cations were leached as a result of gypsum application. Gypsum and the flue gas desulfurization by-product did not significantly affect the acid soils used in these studies or improve alfalfa growth.
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THE PHYSIOLOGICAL BASIS FOR CALCICOLY OF LARREA DIVARICATAMusick, Hugh Bradley, 1947- January 1977 (has links)
No description available.
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