HIGH SOIL CALCIUM SATURATION LIMITS USE OF LEAF POTASSIUM DIAGNOSIS WHEN KCL IS APPLIED IN OIL PALM PLANTATIONS

2017 ◽  
Vol 54 (5) ◽  
pp. 794-804
Author(s):  
BERNARD DUBOS ◽  
VICTOR BARON ◽  
XAVIER BONNEAU ◽  
ALBERT FLORI ◽  
JEAN OLLIVIER

SUMMARYPotassium chloride (KCl) is the most widely used fertilizer in oil palm (Elaeis guineensis) plantations and the rates applied are based on interpretation of leaf K contents. When no positive response on leaf K contents can be detected, no optimum content can be established whatever the yield response to KCl rates. We used data from 13 fertilization trials conducted on several continents to study the responses of leaf K, leaf Cl, leaf Ca and yield to KCl rates as a function of the soil properties of each site. We found that the abundance of exchangeable Ca in the soil expressed as a percent of the cation exchange capacity (CEC) was the best soil variable to predict if leaf K content would increase with KCl rates. In addition, we found that the leaf K contents of unfertilized controls at the end of the trials were also correlated with Ca/CEC. This ratio thus appears to be a better index of soil K reserves than soil exchangeable K content.

1971 ◽  
Vol 51 (3) ◽  
pp. 405-410
Author(s):  
A. K. Ballantyne

Leaching a silt loam soil (cation exchange capacity 23 meq/100 g) with water containing increasing rates of potassium dust (KCl) indicated that high levels adversely affected germination and yields of wheat as well as response to fertilizer. Germination was greatly reduced by the treatment with 22.4 metric tons per hectare and nearly eliminated by 44.8 tons. The 44.8-ton/ha treatment also greatly reduced the yield of grain, but straw weights were affected very little by increasing rates of potassium dust. Response to fertilizer was also reduced by 22.4 and 44.8 tons. The exchangeable Ca and Mg decreased and K increased as increasing amounts of K dust were leached through the soil. The 44.8-ton treatment decreased the exchangeable Ca from 56.0 to 24.9% and the Mg from 21.2 to 4.9%, and increased the K from 7.2 to 51.9%. It would appear that K salts can be added to the soil, without any adverse effects, until the exchangeable K is increased to about 30%. With the soil under study this took more than 11.2 tons per ha (5 short tons/acre). The application of dolomite ameliorated the effect of excess K.


2002 ◽  
Vol 32 (10) ◽  
pp. 1829-1837 ◽  
Author(s):  
J Herbauts ◽  
V Penninckx ◽  
W Gruber ◽  
P Meerts

In a mixed forest stand on an ochreous brown earth in the Belgian Ardennes, pedunculate oak (Quercus robur L.) and European beech (Fagus sylvatica L.) have outwardly decreasing cation concentration profiles in wood. To test if these profiles can be ascribed to endogenous factors or to decreased availability of cations in the soil, radial profiles of water-soluble, exchangeable, and total cations and of cation exchange capacity (CEC) of wood were determined. In both species, [Formula: see text]75% of K is in the water-soluble form so is of little use for dendrochemical monitoring. About 80% of Mg is adsorbed on wood exchange sites. For Ca, 30 (beech) to 60% (oak) of total content cannot be extracted by SrCl2 and is, thus, relatively immobile in wood. Wood CEC decreases from pith to bark in European beech and from pith to outer heartwood in pedunculate oak. Decreasing profiles of exchangeable Ca and Mg in pedunculate oak and exchangeable Ca in European beech are strongly constrained by CEC and, thus, are not related to environmental change. Base cation saturation rate shows no consistent radial change in either species. European beech maintained much higher base cation saturation rate than pedunculate oak, although both species had similar CEC. In conclusion, the results do not provide convincing evidence for a significant change in nutritional status of pedunculate oak and European beech in the Belgian Ardennes due to atmospheric pollution.


1986 ◽  
Vol 58 (2) ◽  
pp. 47-51
Author(s):  
Raina Niskanen

The number of successive extractions with 1 M KCI needed for adequate estimation of effective cation-exchange capacity was studied with four mineral soils. The effective CEC estimated as the sum of equivalents of exchangeable Ca, Mg, Na, H and Al extracted by four successive treatments ranged from 57 to 206 meq/kg soil. In three cultivated soils, 63—90 % of CEC was saturated by Ca and Mg, in the fourth soil (a deeper layer virgin soil), 60 % of CEC by exchangeable H and Al. By two successive treatments often minutes duration with 50ml of 1 M KCI, the equivalent sum of exchangeable cations extracted amounted to 83—92 % of effective CEC in cultivated soils and 67 % of that in virgin soil; >90 % of exchangeable Ca and Mg, 78—97 % of Al, 48—62 % of H and 28—64 % of Na were extracted. By three successive treatments the equivalent sum amounted to 79—96 % of effective CEC, by the single treatment of 30 minutes duration with 100ml of 1 M KCI to 57—79 %. Two successive extractions with 1 M KCI may be enough for estimation of effective CEC in cultivated mineral soils with high degree of saturation by exchangeable Ca and Mg. Soils with high degree of saturation by exchangeable acidity require three successive extractions.


CORD ◽  
1988 ◽  
Vol 4 (01) ◽  
pp. 34
Author(s):  
Doah Dekok Tarigans

This study was conducted to investigate the effects of six co­conut cropping patterns on the soil properties and nutrient element status of coconut leaves. The experiments were carried out from August 1984 to May 1985 in Silang, Cavite, Philippines. Data on‑soil properties and nutrient element starus of coconut leaves were statistically analyzed in Randomized Block Design with three replications. Six cropping patterns in coconut with four species of perennial crops as intercrops, namely: banana, papaya, coffee and pineapple were used in this study. The organic matter, pH and cation exchange capacity of the soils did not differ significantly with cropping pattern although intensively cropped farms tended to have higher organic matter' and cation exchange capacity values. Nitrogen, phosphorus and potassium in the top soil were significantly higher in most intensive intercropped farms, but calcium and magnesium did not vary significantly. Moisture content, waterholding capacity, bulk density and particle density of the soil did not show significant difference with cropping patterns. Likewise, the number of bacteria, fungi and actinomycetes in the soil remained statistically the same. Leaf nitrogen and calcium, in­creased while potassium decreased with intensity of cropping. Phosphorus and magnesium showed no definite trend.


1986 ◽  
Vol 58 (1) ◽  
pp. 1-7
Author(s):  
Raina Niskanen ◽  
Antti Jaakkola

The efficiency of the soil testing method used in Finland for predicting the effective cation-exchange capacity was studied in a material of 430 topsoil samples. The effective cation-exchange capacity was estimated 1) by summation of exchangeable Ca, Mg and acidity displaced by unbuffered 1 M KCI and 2) by summation of exchangeable Ca, Mg, K and Na displaced by neutral 1 M ammonium acetate and exchangeable acidity. In soil testing, Ca, Mg and K were extracted by acid ammonium acetate and soil pH measured in water-suspension. The estimates of the effective CEC were highly correlated and dependent on the clay and organic carbon content and pH(CaCl2) of the soil, the coefficient of multiple determination being over 80 %. Exchangeable Ca was the dominating cation. The proportion of Ca of the effective CEC was about 80 %. Acid ammonium acetate-extractable Ca together with pH(H2O) explained over 80 % of the variation in the effective CEC. For the whole material consisting of mineral soils with great variations in texture, organic carbon content and properties under evaluation, the regression equation predicting the effective CEC (KCI method) was CEC (mval/kg) = 309—56.8pH(H2O) + 0.085Ca(mg/l). Only 16 % of the estimates of the effective CEC calculated with this regression equation deviated more than 15 % from the measured values.


1995 ◽  
Vol 25 (6) ◽  
pp. 997-1007 ◽  
Author(s):  
S. Brais ◽  
C. Camiré ◽  
D. Paré

To assess the impact of forest operations on soil nutrient status, modifications to forest floor, to 0–10 and 10–20 cm mineral soil base status, and to pH were evaluated 5–12 years following whole-tree harvesting and winter windrowing on dry to fresh and moist clayey sites in the clay belt region of northwestern Quebec. Whole-tree harvesting had few impacts on base concentrations and soil pH of dry to fresh sites. On moist sites, significant decreases in pH (−0.60 to −0.84 units), exchangeable Ca, total Ca, and, exchangeable Mg concentrations, base saturation, and effective cation exchange capacity were observed following harvesting. On dry to fresh sites, a decrease in the forest floor weight (−55%) accounted for significant reductions in exchangeable Ca (−55%), total Ca (−61%), and exchangeable K (−40%) pools in this layer, while reserves of both mineral layers were not affected. On moist sites, significant decreases in exchangeable Ca (−42 to −65%) and Mg (−35 to −56%) reserves occurred in all soil layers, while forest floor reserves of total Ca, Mg, and K decreased by 67, 48, and 40%, respectively. These reductions were caused by a loss of substrate in the forest floor (−44%) and a decrease in effective cation exchange capacity, exchangeable Ca saturation, and total Ca concentrations. Impacts of windrowing following whole-tree harvesting were limited to a reduction in reserves of exchangeable Ca (−22%), exchangeable Mg (−27%), total Ca (−20%), and total Mg (−29%) pools of the forest floor of moist sites. Values reported here are much greater than values generally predicted by a balance sheet approach and underline the need for more process-oriented studies. Impacts of these losses on long-term site productivity remain to be investigated.


2013 ◽  
Vol 27 (1) ◽  
pp. 57-67 ◽  
Author(s):  
S.E. Obalum ◽  
J. Oppong ◽  
C.A. Igwe ◽  
Y. Watanabe ◽  
M.E. Obi

Abstract The spatial variability of some physicochemical properties of topsoils/subsoils under secondary forest, grassland fallow, and bare-soil fallow of three locations was evaluated. The data were analyzed and described using classical statistical parameters. Based on the coefficient of variation, bulk density, total porosity, 60-cm-tension moisture content, and soil pH were of low variability. Coarse and fine sand were of moderate variability. Highly variable soil properties included silt, clay, macroporosity, saturated hydraulic conductivity, organic matter concentration, and cation exchange capacity. Overall, soil pH and silt varied the least and the most, respectively. Relative weighting showed that location dominantly influenced the soil variability, except for soil porosity and organic matter concentration influenced mostly by land use. Most of the soil data were normally distributed; others were positively skewed and/or kurtotic. The minimum number of samples (at 25 samples ha-1) required to estimate mean values of soil properties was highly soil property-specific, ranging from 1 (topsoil pH-H2O) to 246 (topsoil silt). Cation exchange capacity of subsoils related fairly strongly with cation exchange capacity of topsoils (R2 = 0.63). Spatial variability data can be used to extrapolate dynamic soil properties across a derived-savanna landscape.


Solid Earth ◽  
2017 ◽  
Vol 8 (4) ◽  
pp. 827-843 ◽  
Author(s):  
Sunday Adenrele Adeniyi ◽  
Willem Petrus de Clercq ◽  
Adriaan van Niekerk

Abstract. Cocoa agroecosystems are a major land-use type in the tropical rainforest belt of West Africa, reportedly associated with several ecological changes, including soil degradation. This study aims to develop a composite soil degradation assessment index (CSDI) for determining the degradation level of cocoa soils under smallholder agroecosystems of southwestern Nigeria. Plots where natural forests have been converted to cocoa agroecosystems of ages 1–10, 11–40, and 41–80 years, respectively representing young cocoa plantations (YCPs), mature cocoa plantations (MCPs), and senescent cocoa plantations (SCPs), were identified to represent the biological cycle of the cocoa tree. Soil samples were collected at a depth of 0 to 20 cm in each plot and analysed in terms of their physical, chemical, and biological properties. Factor analysis of soil data revealed four major interacting soil degradation processes: decline in soil nutrients, loss of soil organic matter, increase in soil acidity, and the breakdown of soil textural characteristics over time. These processes were represented by eight soil properties (extractable zinc, silt, soil organic matter (SOM), cation exchange capacity (CEC), available phosphorus, total porosity, pH, and clay content). These soil properties were subjected to forward stepwise discriminant analysis (STEPDA), and the result showed that four soil properties (extractable zinc, cation exchange capacity, SOM, and clay content) are the most useful in separating the studied soils into YCP, MCP, and SCP. In this way, we have sufficiently eliminated redundancy in the final selection of soil degradation indicators. Based on these four soil parameters, a CSDI was developed and used to classify selected cocoa soils into three different classes of degradation. The results revealed that 65 % of the selected cocoa farms are moderately degraded, while 18 % have a high degradation status. The numerical value of the CSDI as an objective index of soil degradation under cocoa agroecosystems was statistically validated. The results of this study reveal that soil management should promote activities that help to increase organic matter and reduce Zn deficiency over the cocoa growth cycle. Finally, the newly developed CSDI can provide an early warning of soil degradation processes and help farmers and extension officers to implement rehabilitation practices on degraded cocoa soils.


1974 ◽  
Vol 54 (2) ◽  
pp. 195-204 ◽  
Author(s):  
B. KLOOSTERMAN ◽  
L. M. LAVKULICH ◽  
M. K. JOHN

The potential application of a computer soil data file to the study of soil concepts is discussed. This method aids the pedologist to analyze, summarize and correlate large quantities of data. For applied objectives the data file allows the prediction of soil properties for interpretive purposes. The computerized soil data file was used to explore its usefulness in studying the concept of the modal profile, confirmation of definitions of the Podzolic and Gleysolic Great Groups, derivation of equations for estimating soil drainage and cation-exchange capacity, and studying some interrelationships among soil properties. Soil parameters used to define soils at the Order and Great Group levels did trend toward normal distributions for Gleysolic but less for Podzolic soils. The prediction equations for cation-exchange capacity accounted for a higher percentage of the variation than did equations for soil drainage. Many soil property interrelationships were confirmed. The study illustrates some of the weaknesses of using routine soil survey data collected over a 10-yr period.


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