Content Of Exchangeable Bases Research Articles

Título en español.

El abonamiento abundante y las aplicaciones variables de cal a un suelo Cialitos arcilloso (ultisol) durante 7 años consecutivos afectaron marcadamente las propiedades de este suelo y los rendimientos de la caña de azúcar que se sembró luego. Durante el período, las aplicaciones de abono por acre a todas las parcelas fueron 3,680 libras de nitrógeno, 480 de fósforo y 2,870 de potasa. Los rendimientos de la caña aumentaron de menos de 1 tonelada por acre cuando no se aplicó cal, a 40 toneladas cuando se aplicaron 20 toneladas de cal por acre, durante el período de 7 años. Los rendimientos aumentaron, según aumentó el contenido de bases intercambiables en el suelo, de menos de 10 toneladas por acre cuando el contenido era inferior a 3 meq./100 g. de suelo, a más de 40 toneladas cuando estas bases excedieron a 8 meq./100 g. de suelo (58 por ciento de saturación). Los rendimientos aumentaron, según fue disminuyendo el aluminio intercambiable en el suelo, de menos de 10 toneladas por acre, cuando este elemento excedió de 8 meq./100 g. de suelo, a más de 40 toneladas, cuando el contenido de aluminio fue menor de 2 meq./100 g. de suelo. Los rendimientos aumentaron según fue aumentando el pH del suelo, pero la presencia de sales solubles en este suelo, tan abundantemente abonado, hizo que el grado de pH fuera un criterio inadecuado para determinar la necesidad de aplicar cal. La aplicación de 8 toneladas de cal sobre la superficie de un suelo Cialitos arcilloso muy ácido, antes de sembrar la caña, aumentó el rendimiento de ésta de un promedio de 12.4 a 34.5 toneladas por acre y redujo el contenido de aluminio intercambiable de 7.3 a 0.5 meq./100 g. de suelo. Tanto la composición foliar de la caña de 9 meses, como su contenido de sacarosa, no fueron afectados por los factores de suelo que se estudiaron o por las aplicaciones de cal, y continuaron a niveles satisfactorios en las parcelas experimentales de las cuales se obtuvieron producciones, de aproximadamente 0 a más de 40 toneladas de caña por acre. En un reconocimiento que se hizo se encontró que muchos de los suelos que se dedican a la producción de la caña de azúcar en la Región Húmeda del País contenían una cantidad de aluminio intercambiable mayor que la que causó una reducción en el rendimiento de la caña en el experimento que aquí se describe y que se llevó a cabo en un suelo Cialitos arcilloso.

Sugarcane Yields as Related to Acidity of a Humid Tropic Ultisol1

AbstractSugarcane was grown in 40 plots with widely varying pH, base saturation, and exchangeable aluminum contents which resulted from applications of 0 to 45 metric tons of limestone per hectare over a previous 7‐year period while in other crops, receiving a total of 4,180 kg of N, 545 kg of P, and 3,860 kg of K per hectare. Cane yields, sucrose content of the juice, and foliar composition of the leaves were determined. Soil in all plots of this typical ultisol (Cialitos clay) was sampled at end of the experiment.Cane yields increased with increasing exchangeable base content in the upper 15 cm of soil from less than 25 metric tons per hectare when exchangeable bases dropped below 3 meq to over 100 metric tons when exchangeable bases exceeded 8 meq/100 g of soil (58% base saturation).Cane yields increased with decreasing exchangeable Al from less than 25 metric tons per hectare when exchangeable A1 exceeded 8 meq to over 100 metric tons per hectare when exchangeable AI was less than 2 meq/100 g of soil. Yields increased sharply with increasing soil pH. Foliar composition and sucrose content of the sugarcane was not affected by the soil factors studied.

Effects of Liming and Fertilization on Yields and Foliar Composition of High-Yielding Sun-grown Coffee in Puerto Rico

The fertility requirements of high-yielding, intensively managed sungrown coffee growing under favorable climatic conditions in the Mountain Region of Puerto Rico were studied. About 3,000 pounds of market coffee per acre yearly wore produced when fertilization was adequate. Coffee responded strongly to the apnlinf of 300 pounds of nitrogen and 300 pounds of potassium per acre yearly, in three equal applications. Leaf-nitrogen and -potassium contents of 25 to 3.0 percent were associated with high yields. Coffee did not respond to phosphorus or magnesium applications. The effects of liming on yields and foliar composition of heavily fertilized, high-yielding, sun-grown coffee and on soil condition were determined in experiments at two locations in the Mountain Region of Puerto Rico. Soil types on which liming is likely to be especially critical were studied by analyzing soil samples obtained throughout the Mountain Region. Liming had no significant effect on yields of coffee on either Alonso clay near Adjuntas or Los Guineos clay near Jayuya. Liming increased the calcium content and decreased the manganese content, but had no effect on the N, P, K, or Mg content of the coffee leaves. Liming increased soil pH and exchangeable-base content and sharply decreased the exchangeable-aluminum content of both soils. Both soils had a very low, easily reducible manganese content. Severe symptoms of manganese toxicity in intensively managed coffee plantations on soils with a high manganese content were corrected by liming. The soils of the Coffee Region of Puerto Rico fall into three groups as to likelihood of manganese toxicity becoming a problem with intensively managed coffee: Soils low in easily reducible manganese where toxicity of this element is not a problem; soils high in easily reducible manganese, but high in bases and low in acidity where toxicity of this element is not an immediate problem; and acid soils high in easy reducible manganese where toxicity of this element is likely to be an immediate and serious problem.

SOME CHARACTERISTICS OF GRAY SOILS OF LOW BASE SATURATION FROM NORTHEASTERN BRITISH COLUMBIA

Very strongly acid soils of extremely low base saturation have developed under forest vegetation on Cretaceous marine shales in northeastern British Columbia. The soils have light-colored Ae horizons and fine-textured B horizons but the texture becomes finer in the C horizons. Particle size analyses, however, demonstrated that fine clay has accumulated in the B so that the soils have the requisite properties of Orthic Gray Wooded soils. The amount of clay accumulated in the Bt horizons appears to be small and the development of the Bt horizons, therefore, is minimal. The low exchangeable base content of the soils is due to the acidic nature of the parent materials.

Quantitative Evaluation of Soil Reaction and Base Status Changes Resulting from Field Application of Residually Acid-Forming Nitrogen Fertilizers

An evaluation was made of the changes in soil reaction and exchangeable base content of two Red-Yellow Podzolic soils and one alluvial soil resulting from high rates of application of ammonium nitrate and of ammonium sulfate. Severe reductions in exchangeable base level and lowering of soil pH occurred within a year after beginning N applications. The undesirable effects occurred deep in the soil profile where corrections would be difficult, if not impossible, from a practical standpoint. Exchangeable K was lost from the soil faster than other bases at the higher rates of N. No indication of a subsoil zone of accumulation of bases leached out of upper horizons was observed. The measured losses of exchangeable bases were appreciably lower than calculated CaCO3 equivalents of the residual acidity of the fertilizer except for the higher N rates on the Toa clay loam.

Physical and Chemical Properties of Some Iowa Soil Profiles with Clay‐Iron Bands

AbstractField and laboratory studies were made on some sandy soils of Iowa to determine the extent and nature of the clay‐iron bands which occur in some of these soils.Observations made in the field studies indicate that the iron and silicate clay enriched bands have a depth relation to the soil surface under virgin conditions. Also the bands occur often enough in loamy fine sand soils to indicate that the banding phenomenon is the usual rather than the exception in their genesis. Data obtained by fractionation of the < 2µ clay indicate differential movement of the clay fractions in 2 loamy fine sand profiles with iron and silicate clay enriched bands. In a sandy loam profile, no banding of iron and clay or movement of clay size particles was evident.Data from the chemical analyses indicate a very small quantity of bases held in the exchangeable form. Exchangeable base content of the iron band layers was of the order of twice as high as in the interband layers. Exchangeable Ca:Mg ratios were lower in the bands than in the interband layers. Exchangeable Ca:Mg ratios were higher in the profiles studied than those reported for other Gray‐Brown Podzolic and Brunizem soils which have developed from finer textured material. Total nitrogen was higher in the iron‐enriched bands than in the interband layers.In a laboratory experiment, iron bands were produced in a 1‐inch diameter, 4‐foot tube filled with iron containing fine sand by leaching with 0.01 N oxalic acid solution. Though visually evident, the bands were not sufficiently thick to sample for laboratory analysis. The development of bands in the laboratory is considered as additional proof that the bands of iron and clay enrichment observed in the field are the product of profile genesis. Upon drying, the sandy material in the upper part of the leaching tubes was quite strongly cemented.

The Effects of Sodium Chloride on Some Turf Plants and Soils1

The effect of phosphorus and sodium chloride on some common turf plants and soils was studied in a series of greenhouse and laboratory experiments. Phosphorus stimulated the growth of the plants, but sodium chloride in the concentrations used was apparently toxic in some cases and stimulative in others. The toxicity of the sodium chloride was decreased somewhat by the phosphoric acid. Metropolitan bent grass was more tolerant to sodium chloride than Kentucky bluegrass, seaside bent grass, Bermuda grass, or Dutch white clover. Highly significant differences in the effect of phosphorus and sodium chloride on the growth of the different plants were obtained. The total exchangeable base content of the soil was decreased by the treatment with sodium chloride. The results indicate that sodium chloride alone or in combination with phosphate fertilizers may be used on sandy soils for metropolitan and seaside bent grass. However, these experiments are preliminary in nature and further work with nitrogen and potassium fertilizers applied along with salt and on different soil types is necessary to permit of broader conclusions and such work would certainly be very desirable.

MECHANICS OF ENAMEL SUSPENSION, I Exchangeable Base and Viscosity Measurements on Some Vallendar Clays*

ABSTRACTThe results of viscosity measurements upon untreated and electrodialyzed Vallendar clay slips, using borax as an electrolyte in varying concentrations, are set forth and discussed. Several Vallendar clays have been analyzed for exchangeable base content and the results are given.

Rapid methods of examining soils. II. The use of p–nitrophenol for assessing lime status

SummaryBy the use of a solution of p–nitrophenol in lime water a rapid and simple measurement can be made of the lime taken up by a soil sample in reaching neutrality. The same method applied to acid-washed samples gives the exchangeable base content at pH 7.

The Contribution of Clay and Organic Matter to the Base Exchange Capacity of Soils

1. The total exchangeable bases, clay, total carbon and carbon oxidisable by 4 per cent, hydrogen peroxide, have been determined for a number of carbonate soils.2. Assuming soils containing excess of carbonate under natural conditions to be base saturated, equations have been derived connecting exchange capacity with clay and (a) total or (b) “oxidisable” carbon content.3. When the organic matter of these soils was assumed to have a constant base exchange capacity, no correlation was found between the exchange capacity of their clay fractions and either their silica-alumina or their silica-sesquioxide ratios.4. Carbonate soils whose exchangeable base content was appreciably less than the calculated values were found to contain either small amounts of calcium carbonate (< 1 percent.), or the bulk of it was present in coarse form.

The relative proportions of exchangeable bases in some Scottish soils

1. The relative proportions of exchangeable bases in nine soils from the east of Scotland area and the changes effected by dilute chloride solutions have been examined.2. The changes due to N/50 solutions are large, and magnesium is displaced to a greater extent by calcium than by potassium.3. The changes due to N/500 solutions are very small, comparable to what might be expected in manurial practice, and not greater than field sampling error.4. The content of exchangeable bases and their relative proportions, therefore, seem to be fairly permanent for any soil under normal conditions, but vary considerably from soil to soil, and should prove useful as an additional characteristic of soil type as distinguished in the field.

The exchangeable bases in some Scottish soils

1. The exchangeable Fe, Al, Ca, Mg, K, Na have been determined in twenty soils from different parts of the East of Scotland, by extraction with N NH4Cl solution. Data on pH, “Lime Requirement” and loss on ignition are given for the sake of comparison.2. Only three soils were found to contain Fe and Al in exchangeable form.3. The content of exchangeable bases varies from 5·6 to 22·2 milligram-equivalents per 100 gm. air-dried soil.4. The evidence is insufficient to deduce any definite relationship between pH and “Lime Requirement” and the pH cannot be correlated with the content of exchangeable bases except in the case of soils similar in character.5. It is suggested that the differences in the relative proportions of the exchangeable bases indicate that there are on the one hand fundamental differences due to soil type and on the other hand fluctuating differences due to manurial treatment.6. Emphasis is laid on the fact that the degree of saturation of a soil is not necessarily indicated by the content of exchangeable bases. At present the absorptive capacities of the soils examined are not known.7. Until a sufficient number of soils have been examined and classified, it is unlikely that any satisfactory generalisation on the subject of exchangeable bases will be forthcoming.