Determination of phosphorus in calcareous soils by mehlich 3, mehlich 2, cal,and egner extractants

Abstract

Acid extractants were found to be a problem when determining phosphorus in some soils especially in soils with a higher content of carbonates. Carbonate content, soil pH or extractable calcium cannot exactly predict the behavior of a particular soil. On the other hand, measurement of pH after extraction reflects the ability of soil to change the properties of an extractant. The objective of this study was to find the relationships between pH changes during the extraction and the extraction of phosphorus for Mehlich 3, Mehlich 2, CAL, and Egner extractants. Twelve soil samples from various regions of the Czech Republic were taken for investigation. The pH/KCl of the samples was in the range 4.9–7.3. Calcium carbonate was added into the extracting bottles to the soil samples before extraction. The CaCO₃/soil ratio was from 0 to 0.5. The content of phosphorus and pH were measured in filtrates after extraction. The ratio P₁ =P_meas /P_O was calculated for all measurements, all additions of calcium carbonate and all soils. P_meas is the measured value of phosphorus after extraction with the addition of calcium carbonate and P_o is the value of phosphorus determined after the extraction without addition of calcium carbonate. The ratio P_r reflects the changes in the extractability of phosphorus and it is independent of the absolute content of phosphorus in soil. The relationships between P_r and pH after extraction for CAL, Mehlich 2, and Mehlich 3 extractants were found. No such relationship was found for Egner extractant. Correction equations (x=pH after extraction, y=P_r):     

Evaluation of three calcium extractants for coastal plain soils

Abstract

Mehlich 1‐Ca is used as an index to predict the Ca requirement for peanut (Arachis hypogaea L.) fruit development in major peanut growing states. Recently, some concern has been raised about the inadequacy of Mehlich 1 extractable Ca for that purpose. Possible use of alternative extractants for soil Ca has been suggested. In this study, relationships among Mehlich 1, 0.2 M NH₄Cl and 0.01 M NaNO₃ extractable Ca were examined in several Coastal Plain soils to which gypsum or lime had been applied. Variability in extractable Ca was much greater following lime treatment than following gypsum treatment. In Bonifay soil, the quantity of Ca extractable by the three extractants was similar in a gypsum treatment, but in a lime treatment (at an application rate equivalent to the gypsum treatment) Mehlich 1‐Ca was 2 and 5‐fold greater than NH₄Cl‐ and NaNO₃‐Ca, respectively. In Greenville soil, Mehlich 1‐Ca was 3 to 4‐fold greater than NaNO₃‐Ca regardless of gypsum or lime amendment.

For soil samples from a field experiment on Lakeland sand, where lime or gypsum was applied prior to planting, Mehlich 1‐Ca was 7.5 and 2.2‐fold greater than NaNO₃‐Ca for the lime and gypsum treatments, respectively. Greater variability in Mehlich 1‐Ca in lime than in gypsum treatments was due to possible inclusion of undissolved limestone in the soil samples, resulting in overestimation of Ca available for peanut fruits. Mehlich 1‐Ca appears to be an adequate index of soil Ca for prediction of supplemental Ca requirement for peanut if lime has not been applied or has been applied well in advance of planting, thus minimizing the inclusion of undissolved limestone with the soil sample taken from the fruiting zone (0–8 cm depth) 10–14 d after planting.     

Variation of N,P, K,Ca, Mg,Mn, Zn,and al in slash pine foliage

Abstract

The seasonal patterns of foliage nutrient concentrations and contents were monitored for two growing seasons in an 11‐year—old Pinus el1iottii stand. In the first growing season after needle initiation, N, P, K, Mg, and Zn concentrations decreased, but this was followed by an increase in the fall and winter months. Another drop in concentration of all elements, except P, occurred in the second growing season. Decreases in total contents indicated that this drop was a result of translocation to other tissues. In contrast to the mobile elements, the concentration and fascicle contents of Ca, Mn, and Al increased with aging of the needles.

Between‐tree variability was least for N, P, and Zn and the N, K, Mg, Mn, and Zn in the current foliage had consistently lower variation than that in the 1‐year‐old foliage. Between‐tree variation for K was lower in the winter than the spring.

For pine foliage, recommended sampling period for N, P, Mg, and Zn is mid to late summer and for the other elements it is late fall to late winter.

There are several sources of variation that influence the level of nutrients in tree foliage. The most important of these, apart from the tree nutrient status, are seasonal fluctuations, variation between trees, and age of needles . Smaller sources of variation are associated with position of the needles within the crown, diurnal changes, year to year variation, and analytical errors^1,2. These variables must be studied in order to develop suitable sampling techniques and in Pinus this has been undertaken for P. banksiana ¹, P. taeda ³, P. strobus ⁴, P. resinosa ⁴, P. sylvestris ⁵, and P. radiata ^6,7. However, foliage sampling has not been studied in detail for slash pine (Pinus elliottii Englem var. elliottii) and earlier studies with other pines have been largely confined to temperate or cool climates.

This study reports the variation in elemental concentrations with season, age of foliage, and between slash pine trees growing in a subtropical climate in Florida.     

Correlation of Mehlich 3, bray 1, and ammonium acetate extractable P,K, Ca,and Mg for Alaska agricultural soils

Abstract

Soil test recommendations currently used in Alaska are based on a limited amount of in‐state data along with consideration of data from other states. Recently, Mehlich 3 extractable P has been found to be highly correlated to yield on representative agricultural soils in Alaska. To fully use its multi‐element capability, a study was conducted to correlate Mehlich 3 extractable P and cations (K, Ca, and Mg) with the P and cations extracted by the Bray 1 and ammonium acetate methods respectively.

When Mehlich 3 extractable K and Mg were regressed with ammonium acetate extractable K and Mg respectively, the relationship was essentially one‐to‐one and the relationship held across all soils tested. Significant variation was observed among soils in the extraction of Mehlich 3‐P and Ca relative to Bray 1‐P and ammonium acetate‐Ca. Individual soil character appeared to affect the regressions for extractable P and Ca, even though the R² values were generally high. The regression slopes for Mehlich 3‐P versus Bray 1‐P ranged from 1.01 to 1.88 with Mehlich 3 extracting an average of 66% more P than Bray 1 in the volcanic ash soils, and 12% more in the loess soils. The regression slopes for Mehlich 3‐Ca versus ammonium acetate‐Ca ranged from 0.95 to 1.33, and the former extracted an average of 17% more Ca than the latter. It is suggested that the regression data of P and Ca can be extrapolated to other soils based on soil classification; to extend the soil test data over a geographic base.     

熔融制样—X射线荧光光谱法快速测定复合肥中的磷、钾、钙、镁、锰、铁、铜、钠、锌和铝

为实现复合肥样品中多元素的同时分析,采用熔融片法制样,有效地消除了试样的粒度效应,用X射线荧光光谱法测定复合肥样品中磷、钾、钙、镁、锰、铁、铜、钠、锌和铝10个元素,对仪器工作条件进行了试验并选定最佳条件,使各元素测定所要求的灵敏度和准确度得到满足,以8个合成的样品作为校准样品,采用固定理论α影响系数进行回归及基体效应校正,方法精密度(RSD,n=8)≤1.36%,分析结果与化学法进行对照基本一致。     

A comparison of methods for measuring extractable Ca,Mg, K,Na, Mn,Al, Fe,and P from New England forest soils

Abstract

An experiment was designed to evaluate several of the commonly used extractants and methods for determining “available”; elements in soils. The purpose of the study was to evaluate the suitability of these extraction procedures for use on forest soils typical for New England commercial forests. The extraction procedures selected included NH₄OAc pH 4.8, NH₄OAc pH 7.0, NH₄Cl, Double Acid, Bray, and Mehlich methods. The elements measured varied somewhat by procedure but included the base cations, Al, Fe, Mn, and P. As a bioassay of element availability, a greenhouse study was conducted using six forest soil materials from different horizon types (i.e. O, Ap, B) and three conifer seedling species (red spruce, balsam fir, and white pine). Relatively small differences among extraction procedures were found among the methods used for exchangeable Ca, Mg, K, and Na. Large differences, however, were found among the different horizon types in the amount of exchangeable base cations present. In contrast, significant differences were found among extraction procedures for Al, Fe, Mn, and P depending on the degree of buffering and acidity of the extracting solution. Of the elements measured in this study, only P appeared to be growth limiting with the NH₄OAc pH 4.8 being best correlated with P uptake by seedlings. Further work under field conditions over longer time periods is required to evaluate these methods for measuring P availability in forest soils     

Growth and uptake rates of P,K, Ca and Mg in wheat 1

The relation between plant age and nutrient absorption properties of red winter wheat (Triticum aestivum L.) roots were investigated. Understanding the change in ion uptake parameters with increasing plant age is helpful in devising efficient fertilization systems. Such information can be used to determine the nutrient levels needed in the soil to supply nutrients rapidly enough to the root surface to minimize deficiencies. Wheat was grown for periods up to 40 days in solution culture in a controlled climate chamber. Sequential harvest and nutrient influx measurements were made. Shoot growth was exponential with time to 30 days and linear thereafter. Root dry weight increased linearly with time at a slower rate than shoot dry weight. Root length increased linearily with time. With increasing plant age there was a reduction in average P and K uptake rate while average uptake rates for Ca and Mg remained relatively unchanged. With increasing plant age, the maximum influx, I_max. for P and Mg remained constant, but for K and Ca, there was a decrease. For the Michael is constant, Km, no change was observed for P, an increase occurred for K, and a decrease for Ca and Mg, as the wheat plant grew from 5 to 40 days.     

Comparing tests for soil fertility: 1. Conversion equations between olsen and mehlich 3 as phosphorus extractants for 120 soils of south italy

Abstract

The multiple‐element extractant Mehlich 3 (M3) has not been tested extensively in Europe. In this Land, soil‐P test recommendations are based, since decades, on the evaluation of the Olsen‐extractable P, and the optimal soil‐P levels have been established to range between 1.5 and 3.0 mg of Olsen‐P per 100 g of soil. A research programme was started in order to assess the suitability of M3 as routine soil‐P test in European laboratories. As a first approach, we develop conversion equations from Olsen‐P to M3‐P, in order to assess the agreement and the consistency of the measurements under a wide range of chemical and physical soil properties. To this aim, 120 samples with drastically contrasting features were selected within 206 soils collected from all the regions of South Italy. Soil‐P ranges were 0.07–60.53 for M3, and 0.08–21.47 mg/100 g for Olsen. The results showed that M3‐P was a P extractant more efficient than Olsen. The amounts of M3‐P were, on the average, twice as large as the Olsen‐P ones, with mean values of 5.70 and 2.75 mg/100g, respectively. The soil properties exerted a great influence, as well as showed a contrasting effect, on the extraction efficiency of each method. For neutral‐alkaline calcareous soils, the average M3‐P/Olsen‐P ratio increased to 2.52, and the efficiency of M3 poorly varied according to soil pH and CaCO₃ content. On the contrary, in CaCO₃‐free acidic soils, the M3‐P/Olsen‐P ratio decreased to 1.63. In particular, anomalous ratio values less than 1.0 were observed for acidic soils with high content of organo‐mineral complexes with be shifted to 3.7–7.7 for calcareous soils, and to 2.7–4.9 for CaCO₃‐free soils. Field calibrations would give more information to establish the proper values according to either the soil properties and plant requirements. The results encourage the introduction of M3 as routine soil‐P test in our Countries. One must take into account, however, that some soil properties, in particular the CaCO₃ content, migth be considered for a more precise comparative evaluation with existing laboratory data.     

ASI法测定土壤有效P、K、Zn、Cu、Mn与我国常规化学方法的相关性研究

比较了土壤养分状况系统研究法 (ASI法 )测定土壤有效P、K、Zn、Cu、Mn与我国常规化学方法的相关性 ,结果表明ASI法与我国常规化学方法呈显著相关 .盆栽试验进一步验证了ASI方法的土壤磷、钾测定值与作物反应具有良好的相关性     

光倒剌鲃肌肉中钙、磷、铁、锰、锌、铜、硒的初步测定

用常规方法对光倒剌 Spinibarbushollandi Oshima肌肉中几种矿物元素 (亦称生命元素 )进行分析 ,结果表明 :每 1 0 0 g干样中含钙 85.6mg,磷 1 0 0 .4 mg,铁 3.51 mg,锰 2 .4 5mg,锌 5.37mg,铜0 .2 8mg,硒 34 6.3μg。认为光倒剌是一种营养价值较高 ,具有重要开发价值的优质淡水鱼类     

光倒剌繴肌肉中钙、磷、铁、锰、锌、铜、硒的初步测定

用常规方法对光倒剌繵Spinibarbus hollandi Oshima肌肉中几种矿物元素（亦称生命元素）进行分析，结果表明每100g干样中含钙85.6mg,磷100.4mg,铁3.51mg,锰2.45mg,锌5.37mg,铜0.28mg,硒346.3μg。认为光倒剌繵是一种营养价值较高，具有重要开发价值的优质淡水鱼类。     

施肥结构对砂质潮土中微量营养元素空间变化的影响

本文通过长期定位施肥试验 ,分析了不同施肥结构对砂质潮土交换性钙、镁及有效硫、锌、锰、铜、铁等在 0～ 1 2 0cm土体中空间分布变化的影响 .结果表明 ,磷肥明显提高土壤交换性钙的含量 ,而有机肥与氮肥对土壤钙含量无明显影响 .但有机肥显著增加土壤交换性镁含量 ,各层镁含量与有机肥用量呈显著或极显著正相关 ,磷肥同样对土壤镁有提高作用 ,但氮肥无论是否与有机肥配施均降低了土壤各层交换性镁含量 .土壤 0～ 4 0cm有效锌、锰、铁均随有机肥增加而增加 ,并与有机肥用量呈极显著正相关 .而化肥无论是否与有机肥配施均降低土壤有效锌含量 ,但却增加了有效铁含量 .氮肥单施降低土壤有效锰含量 .在无有机肥情况下 ,施磷提高土壤有效铁含量 ,而在施有机肥条件下磷肥则降低耕层有效铁含量 .磷肥只在单施化肥时增加土壤有效锰含量     

Effect of liming on extractable Zn, Cu, Fe and Mn in selected Scottish soils

Ten naturally acidic Scottish soils have been limed with CaCO₃ at 0,0.25, 0.50, 0.75, 1.00 and 1.25 times the recommended lime requirement, and then subjected to three cycles of alternate wetting to field capacity at 20°C for 1 month and drying for 1 month. The Zn, Cu, Fe and Mn extracted by DTPA solution, both at pH 7.3 and also after adjustment to match the final soil pH, were measured by flame AAS. The same elements were determined in ammonium acetate extracts, for extractants buffered at pH 4.8, pH 7.0 or at the final soil pH. The effect of extractant pH upon the amounts of trace elements removed is discussed for the two extractants, with particular reference to Zn. The influence of soil pH upon the amounts of trace elements extracted is also considered. There appears to be a distinct relationship between rate of decrease of DTPA-extractable Fe with increasing soil pH and the effect of pH upon DTPA-extractable Zn, high rates of decrease of extractable Fe being associated with a more continuous decline in extractable Zn with increasing soil pH. Possible reasons for this relationship are discussed, in the light of an experiment conducted to examine the effect of Fe and A1 on loss of Zn from solution at high pH. DTPA-extractable Cu varied little with increasing soil pH.     

Effect of grinding variables on the NH4HCO3 –dtpa soil test values for Fe,Zn, Mn,Cu, P,and K

Abstract

The effect of grinding force, time, and weight of soil on the NH₄HCO₃ ‐DTPA extractable levels of Fe, Zn, Mn, Cu, P and K from 10 Colorado soils were studied. It was found that the amount of extractable iron and zinc increased, with an increase in force or time of grinding. The significant interaction between time and force of grinding indicates that the combined effect of the larger force and the longer time in increasing the extractable levels of Fe and Zn was greater than the additive effects of these factors. The weight of soil being ground had a small effect on extractable Fe (significant at 10% level) and no effect on other elements. Extractable levels of Mn, Cu, P, and K were not affected by the grinding treatments. Iron was increased 112% and zinc was increased 44% due to the combined effects of the larger force and the longer time of grinding in soils averaging 12.8 and 1.1 ppm in Fe and Zn, respectively. It is concluded that grinding variables should be standardized, otherwise interlaboratory comparisons and standardized interpretations of results are not possible.     

Carbon-nitrogen interaction related to P,K, Ca,and Mg nutrients in field crops

Carbon (dry matter)-nitrogen relationship was expressed as DM_t = DM₀ × exp(CNI × N_t) in Gramineae crops (including root crops), and DM_t = DM₀ + CNF × N_t in Leguminosae crops, where DM_t is the amount of dry matter at various growth stages, N_t is the amount of nitrogen absorbed at various growth stages, DM₀ is the initial value, and CNI and CNI′ are coefficients. Thus, since the carbon-nitrogen relationship was different between Gramineae and Leguminosae crops, it is expected that the accumulation processes of other minerals such as phosphorus (P), potassium (K), calcium (Ca), or magnesium (Mg) during growth would be different between Gramineae and Leguminosae crops if these nutrients are closely related to the carbon and nitrogen metabolism. As nitrogen is the most important nutrient for plant growth, the relationship between N_t and the amount of other minerals such as phosphorus (P_t), potassium (K_t), calcium (Ca_t), or magnesium (Mg_t) absorbed in plants at various growth stages was examined in field crops.

In Gramineae crops, the P_t-N_t, K_t-N_t, and Mg_t-N_t relationships during growth were described as follows:

where P₀ and Mg₀ are initial values, and PNI, KNI, K_max, and MgNI are coefficients. Since the P_t-N_t and K_t-N_t relationships changed according to the growing conditions, the values of PNI and KNI were statistically estimated from the data of various growth stages at each treatment. As PNI showed a linear regression with CNI, P_t and also K_t was expressed by the equation which included CNI. Thus both phosphorus and potassium accumulation were closely related to the carbon-nitrogen interaction. While the Mg_t-N_t relationship was less affected by various growing conditions, MgNI was estimated from the data including all treatments, indicating that Mg accumulation was regulated only by nitrogen nutrient. Ca_t was not related to N_t.

In Leguminosae crops, the P_t-N_t, K_t-N_t, and Mg_t-N_t relationships were described as follows:

where P_0, K₀, and Mg₀ are initial values, and PNI′ and KNI′ are coefficients. Since the P_t-N_t, K_t-N_t, and Mg_t-N_t relationships were less affected by various growing conditions as in the case of DM_t-N_t, the values of PNI′ and KNI′, and MgNI were estimated from the data including all treatments. Thus, P, K, and Mg accumulation was closely regulated by N nutrient. Ca_t was not related to N_t.

Consequently, in Gramineae crops, P and K accumulation was assumed to be related to the carbon-nitrogen interaction, while in Leguminosae crops, P and K accumulation was assumed to be related to only nitrogen nutrient, indicating that the role of P and K nutrients differed according to differences in the balance of the carbon-nitrogen metabolism. Since MgNI was estimated from the same form of Mg_t-N_t regression regardless of Gramineae and Leguminosae crops, Mg accumulation was assumed to be closely regulated by only nitrogen nutrient. Ca accumulation was neither related to N nutrient nor carbon-nitrogen interaction.     

鸡粪等有机肥料的养分释放及对土壤有效铜、锌、铁、锰含量的影响

采用室内培养法研究鸡粪、牛粪和猪粪等畜禽有机肥料的矿化率和速效氮、磷、钾养分释放特性,并探讨施用有机肥料对土壤有效铜、锌、铁、锰含量的影响。结果表明,鸡粪、牛粪和猪粪等畜禽有机肥料当季(120d)有机碳矿化率分别为87．5％、71．9％和55．4％,碱解氮释放量分别为39．9％、20．6％和35．3％,速效磷释放量分别为24．6％、61．3％和34．8％,速效钾释放量分别为78．8％、36．8％和41．5％。供试条件下土壤有效铜、锰含量增加,但有效锌含量降低,施用鸡粪可使土壤有效铁含量增加,而施用牛粪和猪粪则使土壤有效铁含量降低。     

鸡粪等有机肥料的养分释放及土壤有效铜、锌、铁、锰含量的影响

采用室内培养法研究鸡粪、牛粪和猪粪等畜禽有机肥料的矿化率和速效氮、磷、钾养分释放特性,并探讨施用有机肥料对土壤有效铜、锌、铁、锰含量的影响.结果表明,鸡粪、牛粪和猪粪等畜禽有机肥料当季(120d)有机碳矿化率分别为87.5%、71.9%和55.4%,碱解氮释放量分别为39.9%、20.6%和35.3%,速效磷释放量分别为24.6%、61.3%和34.8%,速效钾释放量分别为78.8%、36.8%和41.5%.供试条件下土壤有效铜、锰含量增加,但有效锌含量降低,施用鸡粪可使土壤有效铁含量增加,而施用牛粪和猪粪则使土壤有效铁含量降低.     

Influence of organic amendments on Fe,Cu, Mn,and Zn availability and clay minerals of different soils

The effects of application of composted olive mill wastewater sludge (A) and depotassified sugarbeet vinasse (V) on total diethylenetriaminepentaacetic acid (DTPA) and sequential extracted micronutrients were investigated. The mineralogy of the fine fraction of soils was also studied. The soils used were a Typic Rhodoxeralf (soil R), a Typic Xeropsamment (soil S), and a Typic Xerorthent (soil C). Fertilization with A and V during 3 years, in general did not significantly affect the total concentration of Fe, Cu, Mn, and Zn versus the control. However, the elements extracted with DTPA generally increased with the organic amendments, more with A than with V. The BCR (European Community Bureau of Reference) sequential extraction indicated that the addition of organic matter generally increased Zn and Mn in the two more available fractions. A great amount of Fe was found in the second and third fractions from the unamended and amended soils. Nevertheless, the sum of the three fractions was enhanced for the organic amendment, except for calcareous soil. The distribution of these elements in the different fractions was significantly affected by the type of soil. The addition of both fertilizers caused modifications in particle size and consequence redistribution of the calcite content between the different fractions.     

Bragg soybeans grown on a southern coastal plain soil III. Seasonal changes in nodal Fe,Zn, and Mn concentrations

Determinate soybean [Glyclne max (L.) Merr.] has been characterized by few detailed micronutrlent partitioning studies. Knowledge of the variation in mlcronutrient concentrations with plant part, nodal position, and plant age is needed for a better understanding of plant functions. In this field study, ‘Bragg’ soybean were grown on an Aquic Paleudult soil (Series Goldsboro loamy sand). Plants were sampled at 10–14 day intervals beginning 44 days after planting (July 7) until harvest. Maximum observed Fe concentrations were 152, 276, 259, and 191 ppm for stem internodes, petioles (+ branches), leaf blades, and pods, respectively. Maximum observed Zn concentrations were 118, 91, 95, and 112 ppm for the same respective plant parts. Maximum observed Mn concentrations were 41, 73, 134, and 63 ppm for the same respective plant parts. Nodal and temporal mean concentra tlons of Fe, Zn, and Mn generally varied considerably due to plant age and nodal position, respectively, in all plant parts. These data document that for plant analysis, mean concentrations of elements in all four plant parts can vary by several fold depending upon plant age and nodal composition of the sample. Regression equations and associated response surfaces will be extremely useful in the development of accurate plant growth models which describe Fe, Zn, and Mn concentrations and translocations among parts of determinate soybean.