scholarly journals Fixation of potassium by soil samples under various conditions

1965 ◽  
Vol 37 (3) ◽  
pp. 195-206
Author(s):  
Armi Kaila

The fixation of added potassium under various conditions was studied using soil samples collected from three layers of ten mineral soils. The type of soil ranged from finesand to heavy clay, the soil reaction from pH 3.3 to pH 6.4 (in 0.01 M CaCl2), and the total potassium content from 1.99 to 3.41 per cent. The fixation against an extraction with neutral ammonium acetate distinctly depended on the conditions used for the application of potassium: on the average, without drying the samples fixed during one hour somewhat more than 80 per cent of the amount fixed during 18 hours, when the samples were treated with KCI-solutions corresponding to 2.5 me K/100 g soil. Drying the suspension at 80°C resulted in a fixation 1.2 to 4.1 times as high as that under the »wet» conditions within one hour. The results of these two methods were not particularly closely correlated (r = 0.73***). The results of the »dry» method were found to be of the same order as the fixation of potassium in samples incubated for three months at room temperature. The results of the »dry» fixation were positively correlated with the pH (r = 0.75***) and negatively correlated with the contents of organic carbon (r = —0.63***) and exchangeable potassium (r = —0.40*), but they were not correlated with the contents of clay or the acid soluble potassium. Under the »wet» conditions the relative fixation generally decreased with an increase in the application of potassium, but there were samples which fixed a rather low but almost equal portion of all the applications from 0.625 to 40 me K/100 g soil. The fixation from the highest addition was correlated with the clay fraction

1973 ◽  
Vol 45 (2) ◽  
pp. 121-215
Author(s):  
Johan Korkman

A method for determining total sulphur in plant material and soil samples using the induction furnace technique and subsequent turbidimetric determination of sulphate sulphur was discussed. A procedure for extracting sulphur from soil samples with ammonium acetate (pH 4.65), the interference of the organic matter being reduced by oxidation of the extract with H2O2, was proposed. Sulphur balance in Finnish cultivated soils was estimated by taking into account the average amounts of emitted (8 kg S/ha/yr.), precipitated (8 kg S/ha/yr.) and leached (8 kg S/ha/yr.) sulphur. The actual situation in the cultivated soils seems thus to be depending, on an average, on the uptake by plants and the sulphur applied (12 kg S/ha/yr. in the early 1970s). In 104 samples of cultivated soil, the content of total sulphur showed a slight correlation with the content of organic carbon. The amounts of sulphur extracted in various ways were not predictable by means of the soil characteristics used (pHCaCl2, org. C and texture). Extracted sulphur did not correlate sufficiently with the development and sulphur uptake of plants. Under field conditions in northern Finland, sulphur application produced a relatively distinct result in respect both to the ley yields on Carex peat, and their sulphur content. On mineral soils in southern Finland the yields were unaffected by supplementary fertilization with sulphur. In the pot experiments performed a fairly close relationship between sulphur and nitrogen was demonstrated.


1973 ◽  
Vol 45 (3) ◽  
pp. 319-324
Author(s):  
Armi Kaila ◽  
Helinä Kettunen

Uptake of magnesium from a sand, fine sand, muddy clay, silty clay and heavy clay soil under exhaustive cropping with perennial rye grass was studied in green house. An application of 0.5 g Mg as MgSO4 ∙ 7 H2O per the 5-liter pots increased slightly the total yield of rye grass shoots and markedly the amount of Mg harvested in the shoots from the sand and fine sand soils with an initial content of only 14 and 37 ppm exchangeable Mg, respectively. No respond to the application of Mg was detected in the silty clay and heavy clay soils which contained exchangeable Mg 226 and 910 ppm, respectively. The muddy clay soil contained 137 ppm exchangeable Mg, and the application of Mg markedly increased the amount of Mg harvested in the shoots, but brought about a decrease in the yield of shoots. The amount of Mg harvested in the shoots without the application of Mg was only in the sand and fine sand soils higher than the original content of exchangeable Mg. Yet, in all soils except in the muddy clay, the decrease in the content of exchangeable Mg during the cropping was lower than the amount of Mg harvested. This was taken to indicate that some release of nonexchangeable Mg did occur during this trial. According to a rough estimation this mobilization of Mg varied from 0 to 60 ppm, whereas the corresponding release of nonexchangeable K was 500–1000 ppm, except in the sand soil. The »exhaustion Mg», or the sum of Mg harvested in the shoots of rye grass and the exchangeable Mg in the soil after cropping, was in all soils of the same order as the amount of Mg extracted by 0.05 N or 0.1 N HCI from the original soil samples.


1963 ◽  
Vol 43 (1) ◽  
pp. 123-134 ◽  
Author(s):  
A. J. MacLean ◽  
J. E. Brydon

The average amount of non-exchangeable potassium removed by H-resin and boiling 1 N HNO3 from the clay in eleven Canadian soils was about twice that in the fine silt, about four times that in the medium silt, and about eleven times that in the coarse silt and sand. Continuous leaching with 0.01 N HCl also removed four times as much potassium from the clay as from the medium silt. The amounts released were usually less from the clay of four Podzols than from the clays of a Brown Chernozemic, a Brown Podzolic, a Brown Forest, and three Dark Grey Gleysolic soils.The percentage of total potassium released from K-bearing minerals by the above procedures was usually in the following order: feldspar < illite < muscovite < biotite.Although fixation of added potassium against extraction with ammonium acetate usually decreased with increasing particle-size, there was considerable fixation in the fine and medium silts. The clays of two Dark Grey Gleysolic and a Brown Forest soil fixed the highest amounts of potassium.Differences in the release and fixation of potassium were not related to the contents of feldspar, illite, vermiculite and mixed-layer minerals in the clays, nor to the amounts of feldspar and mica in the non-clay fractions.


2012 ◽  
Vol 36 (4) ◽  
pp. 1131-1148 ◽  
Author(s):  
Thayse Aparecida Dourado ◽  
Laura Fernanda Simões da Silva ◽  
Mara de Andrade Marinho

The dispersion of the samples in soil particle-size analysis is a fundamental step, which is commonly achieved with a combination of chemical agents and mechanical agitation. The purpose of this study was to evaluate the efficiency of a low-speed reciprocal shaker for the mechanical dispersion of soil samples of different textural classes. The particle size of 61 soil samples was analyzed in four replications, using the pipette method to determine the clay fraction and sieving to determine coarse, fine and total sand fractions. The silt content was obtained by difference. To evaluate the performance, the results of the reciprocal shaker (RSh) were compared with data of the same soil samples available in reports of the Proficiency testing for Soil Analysis Laboratories of the Agronomic Institute of Campinas (Prolab/IAC). The accuracy was analyzed based on the maximum and minimum values defining the confidence intervals for the particle-size fractions of each soil sample. Graphical indicators were also used for data comparison, based on dispersion and linear adjustment. The descriptive statistics indicated predominantly low variability in more than 90 % of the results for sand, medium-textured and clay samples, and for 68 % of the results for heavy clay samples, indicating satisfactory repeatability of measurements with the RSh. Medium variability was frequently associated with silt, followed by the fine sand fraction. The sensitivity analyses indicated an accuracy of 100 % for the three main separates (total sand, silt and clay), in all 52 samples of the textural classes heavy clay, clay and medium. For the nine sand soil samples, the average accuracy was 85.2 %; highest deviations were observed for the silt fraction. In relation to the linear adjustments, the correlation coefficients of 0.93 (silt) or > 0.93 (total sand and clay), as well as the differences between the angular coefficients and the unit < 0.16, indicated a high correlation between the reference data (Prolab/IAC) and results obtained with the RSh. In conclusion, the mechanical dispersion by the reciprocal shaker of soil samples of different textural classes was satisfactory. The results allowed recommending the use of the equipment at low agitation for particle size- analysis. The advantages of this Brazilian apparatus are its low cost, the possibility to simultaneously analyze a great number of samples using ordinary, easily replaceable glass or plastic bottles.


1966 ◽  
Vol 38 (1) ◽  
pp. 49-58
Author(s):  
Armi Kaila

The nonexchangeable or fixed NH4-N was determined by the method of SCHACHTSCHABEL in 130 samples of Finnish mineral soils. In this relatively heterogeneous material consisting of 44 samples from the surface layer down to 20 cm and 86 samples from the deeper layers, the pH values ranged from 3.3 to 7.5, the contents of clay from 0 to 96 per cent, organic C from 0.03 to 6.6 per cent, and Kjeldahl-N from 0.13 to 4.53 mg/g. In the 46 finesand, loam and silt soil samples, the content of nonexchangeable NH4-N was, on the average, 90 ± 30 ppm ranging from 0 to 190 ppm. In the 84 clay soil samples it ranged from 40 to 620 ppm, with an average of 290 ± 30 ppm. The heavy clay soils of the deeper layers were particularly rich in fixed NH4-N containing it averagely 400 ± 40 ppm. Because of these soils the mean value in the samples of the deeper layers was as high as 260 ± 30 ppm and thus significantly higher than the corresponding figure in the surface soils, 140 ± 40 ppm. In the clay soils the amount of nonexchangeable ammonium was correlated with the clay fraction less than 0.6 μ (r = 0.74***), but not at all with the coarser clay. In the finesand, loam, and silt soils no correlation between the contents of fixed ammonium and clay was detected. No close relationship existed between the indigenous fixed ammonium and the capacity of the soil to fix applied ammonium. If the sum of these quantities would represent the total ammonium fixing capacity of the soil, about one half of this capacity would be saturated by the native fixed ammonium in the topsoil. In the subsoils the rate of saturation would be much lower. In the topsoil samples the amount of nonexchangeable NH4-N corresponded in the non-clay soils to 4 ± 2 per cent and in the clay soils to 9 ± 3 per cent of the Kjeldahl-N. In the subsoil samples the corresponding average percentage was 52 ± 5. The rather low ratios of organic C to Kjeldahl-N in the clay soils of the deeper layers may be taken to indicate that a part of the Kjeldahl-N was not in organic compounds. The C/N-ratios obtained when the amount of nonexchangeable NH4-N is subtracted from the Kjeldahl-N may be too high to characterize the soil organic matter, since it is likely that all the fixed NH4-N was not determined by the Kjeldahl-procedure.


2017 ◽  
Vol 48 (2) ◽  
Author(s):  
R. A. Al-Tamimi

This research was conducted to study potassium status and forms in some desert Torrifluvents soil, from south of Libya and to clarify the effect of cultivation on its forms. Composite soil samples were collected from surface soils (0-30 cm) of some cultivated fields and from larva regions besides these fields. Various forms of potassium were determined i.e. soluble-K, NH4OAC extractable-K, reserve-K, sulphuric acid-K, boiling nitric acid-K to determine primary step-K and total step-K, and total K. Results indicated that all soils have high content of soluble and exchangeable potassium, and within the range of arid and semi–arid soils. Reserve-K was ranged between 0.359– 3.422 cmol kg-1 with an average of 1.702 and 2.637 cmol kg-1 in cultivated and virgin soils respectively. All soils had low content of primary step which ranged between 0.214-1.294 cmol kg-1 with an average of 0.522 and 0.926 cmol kg-1 in cultivated and virgin soils respectively. Total step potassium was ranged between 0.982–5.995 cmol kg-1 with average of 2.480 and 3.765 cmol kg-1 for cultivated and larva soils respectively. Total potassium concentration was between 15.16–36.71 and 23.53-30.06 cmol kg-1 with average of 24.52 and 26.38 in cultivated and virgin soils respectively. All forms of potassium were decreased as a result of cultivation. Apart from K-HCl and total K, the rest forms of potassium were significantly correlated with each other's.


Soil Research ◽  
1972 ◽  
Vol 10 (1) ◽  
pp. 95 ◽  
Author(s):  
IF Fergus ◽  
AE Martin ◽  
IP Little ◽  
KP Haydock

Setaria (Setaria sphacelata cv. Nandi) was grown in 10 surface soils, of contrasting properties, in pots until (after repeated harvesting of tops) plant growth virtually ceased. Uptake of potassium by tops and roots was correlated with change in exchangeable potassium during cropping, initial exchangeable potassium, and with quantities of potassium predicted from the immediate Q/I relations of the soils. Some initially non-exchangeable potassium was absorbed from seven of the soils by the plants, such that these soil quantity parameters (which were statistically equivalent) predicted two-thirds of the total potassium uptake averaged over all soils. Potassium uptake was also correlated with soil potassium soluble in constant-boiling hydrochloric acid, and with potassium extracted by a cation exchange resin (both of which predicted about twice the plant absorption). For six of the soils, uptake of initially non-exchangeable potassium was correlated with the quantity of total potassium present in each pot in the 1 0 . 1 pm clay fraction. The intensity of soil potassium (measured in dilute calcium chloride solution from the immediate Q/I relation) was reduced on all soils by exhaustive cropping to a mean value for the equilibrium activity ratio (AR0) of 4.7 10-4 mole1/2 L.-1/2 (�G = -4500 cal equiv.-1); it was suggested that the observed variations in this value were unlikely to prohibit its use for practical soil testing, except for the prediction of the quantity parameter for those soils for which the form of the isotherm is altered by cropping. A tentative value for the potential of soil potassium at which setaria has an adequate average potassium concentration in its tops was - 3600 cal equiv.-1 (AR0 2.1 x 10-4 mole1/2 L.-1/2).


1967 ◽  
Vol 39 (2) ◽  
pp. 107-118
Author(s):  
Armi Kaila

Release of nonexchangeable potassium by treatment with 1 N HCI at 50°C was studied on basis of a material consisting of 330 samples of Finnish mineral soils. The results ranged from 1 to 830mg K/100g. The mean content of nonexchangeable acid-soluble potassium was in the surface samples of sand and fine sand soils 95±26 mg/100 g, in loam soils 165±31 mg/100 g, in silt soils 195±52 mg/100 g, in clay loam soils 258±32 mg/100 g, in silty clay soils 283±43 mg/100 g, and in heavy clay soils 345±126 mg/100 g. In the subsoil samples of loam, clay loam, silty clay and heavy clay soils the mean content was significantly higher than in the surface samples, or 283±51 mg/100 g, 404±56 mg/100 g, 535±53 mg/100 g, and 580±37 mg/100 g, respectively. The results seem to be high as compared with data reported from Sweden, Norway and Germany. The content of nonexchangeable potassium released by acid was to some extent connected with the clay content: the correlation coefficient in the whole material was r = 0.74***, but only about 0.5*** both in the separate groups of the 178 nonclay samples and the 152 clay samples. There was only a very low correlation between the contents of nonexchangeable acid-soluble potassium and readily exchangeable potassium. A somewhat higher correlation, r = 0.65***, was found for the relationship between the former and fixation of added potassium under »wet» conditions, but it was markedly decreased by the elimination of the effect of the clay content. Nonexchangeable acid-soluble potassium usually represented a lower part of the total potassium in the surface samples than in the subsoil samples, and also the proportion tended to be higher in the clay soils than in the coarser soils. It varied from 0.2 to 26.3 per cent in the small material studied. In most cultivated soils less nonexchangeable potassium was released from the samples of plough layer than from samples of deeper layers. In a podsol profile the minimum content of nonexchangeable and exchangeable potassium and the maximum of fixation of added potassium was found in the A2 horizon; in a brown podsolic soil all these test values decreased fairly regularly with depth. From some silt and silty clay soils incubated for three months at room temperature a large part, even more than 40 per cent of the added potassium was not recovered by the acid extraction. Ammonium acetate extracted from 9 to 85 per cent of the potassium applied before incubation, and the part of added potassium found as nonexchangeable acid-soluble form varied from 5 to 53 per cent. The equilibrium between the different potassium fractions in soil was discussed. It was supposed that differences in the ability of plants to utilize nonexchangeable potassium may partly depend on the level to which plant roots are able to decrease potassium concentration in the solution around the minerals.


1986 ◽  
Vol 58 (2) ◽  
pp. 43-46
Author(s):  
Helinä Hartikainen

The base-neutralizing capacity, BMC7 (OH- as meq kg-1 needed to raise soil pH to 7), was determined graphically from curves obtained in KOH titration (at a constant ionic strength of I = 0.1). In 84 soil samples, BMC7 amounted to 0—316 meq kg-1, being highest in the heavy clay soils and lowest in the non-clay soils. In different textural groups, BMC7 seemed most markedly to be dependent on the initial soil pH, followed by organic C or oxalate soluble Al, in the coarser clays also on clay content. The results evidence that in determination of lime requirement, attention should be paid to the capacity of soil acidity. In routine soil testing, detailed lime recommendations for various soil types are needed.


1969 ◽  
Vol 41 (1) ◽  
pp. 60-67
Author(s):  
Mikko Sillanpää ◽  
Esko Lakanen

The use of acid ammonium acetate (pH 4.65) as an extractant for plant available trace elements (Mg included) was studied on a total of 216 soil samples and of timothy samples from corresponding sites. Significant correlations between the results of soil and plant analyses were obtained for the eight elements studied in following soil groups: (1) Clay soils: Ni, Co, Cu (2) Coarse mineral soils: Ni, Co, Pb, Mg, Mo (3) Mineral soils (Groups 1 + 2): Ni, Co, Pb, Cu, Mo, Zn (4) Organogenic soils: Ni, Co, Pb, Mg, Mn (5) Whole material: Ni, Co, Pb, Cu, Mg, Mn, Mo, Zn.


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