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1. Phosphate Fixation in Soils—A Critical Review

Author:
A. R. Midgley
Source:
Soil Science Society of America journal 1941 v.5 no.C pp. 24-30
ISSN:
0361-5995
Subject:
B horizons; acid soils; adsorption; alkaline soils; alkalinity; aluminum; aluminum oxide; anions; apatite; calcareous soils; calcium; chemical precipitation; citrates; citric acid; colloids; crystal structure; fertilizers; films (materials); fluorine; iron; iron oxides; iron phosphates; kaolinite; laterites; oxalates; sodium silicate; soil solution; soluble phosphates; superphosphate; tricalcium phosphate; water solubility
Abstract:
... Discussion and SummaryWhen phosphates are applied to soils they readily change to less soluble forms, the availability of which varies greatly depending upon the degree of fixation. It is difficult to distinguish between fixation by adsorption and chemical precipitation, especially in view of recent results obtained by Stout (26). He reports that the crystal structure of kaolinite changed to a new ...
DOI:
10.2136/sssaj1941.036159950005000C0004x

2. Iron Oxide Removal from Soils and Clays

Author:
N. H. Aguilera; M. L. Jackson
Source:
Soil Science Society of America journal 1953 v.17 no.4 pp. 359-364
ISSN:
0361-5995
Subject:
citrates; clay; coatings; crystals; dithionite; hematite; iron; magnetite; pH; sand; silicates; silt; sodium; soil; sulfides; sulfur
Abstract:
... Iron oxide coatings or crystals must be removed from soils in which they are found in many mineralogical techniques for identification of colloidal layer silicates as well as the identification of silt and sand grains with the polarizing microscope. A procedure is presented which employs sodium dithionite (Na₂S₂O₄, hyposulfite, or “hydrosulfite”) as the reductor, and 0.3 molar citrate with or with ...
DOI:
10.2136/sssaj1953.03615995001700040015x

3. The Plant Availability of Various Sources of Phosphate Rock

Author:
W. H. Armiger; Maurice Fried
Source:
Soil Science Society of America journal 1957 v.21 no.2 pp. 183-188
ISSN:
0361-5995
Subject:
alfalfa; ammonium; apatite; buckwheat; carbonates; citrates; citric acid; fluorine; greenhouse experimentation; phosphorus; plant growth; prediction; rock phosphate; rocks; solubility; Curacao; Florida; Idaho; South Carolina; Tennessee; Virginia
Abstract:
... Greenhouse experiments were conducted with buckwheat and alfalfa in which 10 sources of phosphate rock were compared as agronomic sources of phosphorus. Tunisian rock gave the largest plant growth response and supplied more phosphorus than other rocks of either foreign or domestic origin. Of the domestic sources, South Carolina land rock and 1 of 2 Florida land pebbles rated highest. However, Sout ...
DOI:
10.2136/sssaj1957.03615995002100020013x

4. The Reaction of Wool With Sodium Hydroxide in Concentrated Salt Solutions

Author:
J.R. McPhee
Source:
Textile research journal 1959 v.29 no.4 pp. 303-310
ISSN:
0040-5175
Subject:
acetates; anions; bromides; carbonates; cations; chlorides; citrates; fabrics; iodides; lithium; nitrites; potassium; reducing agents; sodium; sodium bisulfite; sodium hydroxide; sorption; textile fibers; thiocyanates; thiosulfates; wool
Abstract:
... The properties of wool after treatment with sodium hydroxide in a series of 2 M aqueous salt solutions show that anions protect from alkaline degradation in the order S₂O₃ ᶻ, SO₈ ᶻ, citrate > CO₃ ᶻ> 50₄ ᶻ > C₂H ₃O₂- > Cl- > Br- > NO₂- > I- > CNS-, while cations protect in the order Li⁺, Na⁺ > K⁺. The swelling of wool is decreased by some 2 M salt solutions (S₂O₂ ᶻ) but is unaffected by others (CNS ...
DOI:
10.1177/004051755902900403

5. Yield Response in Experiments With Phosphorus Fertilizers in Relation to: I. Meaningful Differences Among Sources on Acid Soils of the Southeastern States

Author:
G. L. Terman
Source:
Soil Science Society of America journal 1960 v.24 no.5 pp. 356-360
ISSN:
0361-5995
Subject:
acid soils; citrates; corn; cotton; crop yield; crops; forage; phosphorus; phosphorus fertilizers; probability; superphosphate
Abstract:
... Yield results from 174 phosphorus rate and source experiments conducted in the Southeast, each including a response curve with CSP (concentrated superphosphate), were examined in relation to the nature of the response and experimental error. In only a few of the tests with various crops showing yield response to P was it possible at the 5% probability level to measure differences among citrate- an ...
DOI:
10.2136/sssaj1960.03615995002400050016x

6. Properties of Intergradient Chlorite-Expansible Layer Silicates of Soils

Author:
J. B. Dixon; M. L. Jackson
Source:
Soil Science Society of America journal 1962 v.26 no.4 pp. 358-362
ISSN:
0361-5995
Subject:
aluminum; aluminum oxide; cation exchange capacity; citrates; clay; clay fraction; fluorides; heat stability; iron; silicates; silicon; temperature
Abstract:
... Clay fractions of soils which contain intergrades of chlorite-expansible 2:1 layer silicates from three states were studied. The citrate, fluoride, and 400° and 500°C. dehyroxylation-NaOH methods of removing the interlayer materials were compared. The latter method removed more interlayer material than either of the other two methods as indicated by greater collapse of potassium-saturated samples ...
DOI:
10.2136/sssaj1962.03615995002600040016x

7. Relative Availability of Phosphorus in Fertilizers Varying in Solubility of the Phosphorus

Author:
Bill C. Wright; B. C. Murphy; J. W. Gilliam
Source:
Soil Science Society of America journal 1965 v.29 no.4 pp. 423-426
ISSN:
0361-5995
Subject:
NPK fertilizers; Zea mays; ammonium; citrates; corn; crops; greenhouses; phosphorus; phosphorus fertilizers; superphosphate; water solubility; Netherlands
Abstract:
... Twenty-eight NPK fertilizers varying in solubility of the phosphorus were compared by band application and cropping to corn (Zea mays L.) in the greenhouse. Phosphorus uptake and per cent superphosphate equivalent were determined for each of two crops and for a combination of both crops. The per cent superphosphate equivalent ranged from 14 to 135 in the first crop, from 15 to 98 in the second cro ...
DOI:
10.2136/sssaj1965.03615995002900040023x

8. Use of Amorphous Material to Identify Spodic Horizons

Author:
D. P. Franzmeier; B. F. Hajek; C. H. Simonson
Source:
Soil Science Society of America journal 1965 v.29 no.6 pp. 737-743
ISSN:
0361-5995
Subject:
B horizons; Podzols; aluminum; cation exchange capacity; citrates; coatings; diagnostic horizons; dithionite; heat; heat treatment; iron; pellets; reducing agents; spodic horizons; total organic carbon; New York
Abstract:
... The illuvial amorphous material that occurs as pellets or grain coatings in the B horizons of some New York Podzols contains much carbon, iron, and aluminum. This amorphous material has high cation-exchange capacity (CEC) that can be destroyed by heat treatment or extraction with solutions of a complexing agent (citrate or pyrophosphate) combined with a reducing agent (dithionite). Most of the car ...
DOI:
10.2136/sssaj1965.03615995002900060038x

9. Colorimetric Determination of Iron of Mixed Valency by Orthophenanthroline

Author:
G. S. R. Krishna Murti; V. V. Volk; M. L. Jackson
Source:
Soil Science Society of America journal 1966 v.30 no.5 pp. 663-664
ISSN:
0361-5995
Subject:
citrates; color; colorimetry; hydroxylamine; hydroxylation; iron; pH; sodium acetate
Abstract:
... A colorimetric method for the determination of Fe in a mixed Fe³⁺ and Fe²⁺ valency system has been proposed. Complete reduction of Fe³⁺ to Fe²⁺, which was essential for the formation of a stable colored complex with orthophenanthroline, was obtained when the iron solution, buffered at pH 3.5 with sodium acetate, was heated for 1 hr at 65C with 5% hydroxylamine hydrochloride. This reduction procedu ...
DOI:
10.2136/sssaj1966.03615995003000050037x

10. Effect of Partial Acidulation and Elemental Sulfur on Availability of Phosphorus in Rock Phosphate

Author:
D. L. Ashby; W. E. Fenster; O. J. Attoe
Source:
Agronomy journal 1966 v.58 no.6 pp. 621-625
ISSN:
0002-1962
Subject:
Lolium; acidification; agronomy; citrates; fertilizers; greenhouses; phosphorus; rock phosphate; silt; soil pH; sulfur; water solubility
Abstract:
... A study was made of the effect of partial acidulation of rock phosphate, coating with elemental S, granule size, placement, and soil pH on yield and uptake of P and S by ryegrass grown on Miami (pH 6.7) and Dubuque (pH 6.0 and 7.0) silt loams in the greenhouse. In most cases, both yield and P uptake increased with each increase in level of acidulation; however, the results for the 50 and 100% leve ...
DOI:
10.2134/agronj1966.00021962005800060021x

11. Contributions of Fixed Charge and Mobile Complexing Agents to the Diffusion of Zinc

Author:
J. F. Hodgson; W. L. Lindsay; W. D. Kemper
Source:
Soil Science Society of America journal 1967 v.31 no.3 pp. 410-413
ISSN:
0361-5995
Subject:
calcium carbonate; citrates; gels; moieties; polygalacturonic acid; zinc
Abstract:
... Zinc was allowed to diffuse from a ZnCO₃ precipitate through an agar-agar gel to a stream of continuously flowing water. In one treatment, part of the agar-agar was replaced by Ca-poly-galacturonate to incorporate fixed negative charges in the gel in the form of carboxyl groups. In a second treatment, Cacitrate was introduced into the flowing stream of water. In every case, all phases of the syste ...
DOI:
10.2136/sssaj1967.03615995003100030033x

12. Efficient and Inefficient Use of Iron by Two Soybean Genotypes and Their Isolines

Author:
J. C. Brown; C. R. Weber; B. E. Caldwell
Source:
Agronomy journal 1967 v.59 no.5 pp. 459-462
ISSN:
0002-1962
Subject:
absorption; agronomy; citrates; culture media; iron; isogenic lines; pH; soybeans
Abstract:
... Iron-efficient ‘Hawkeye’ and iron-inefficient PI-54619-5-1 soybean genotypes and their isolines A62-9 (iron efficient) and A62-10 (iron inefficient) were grown comparatively on soils and solution cultures. There was a differentfal response in the iron-efficient soybeans. A62-9 was less efficient than Hawkeye. This loss in efficiency was related to a loss in the ability of A62-9 to reduce Fe⁺⁺⁺ to ...
DOI:
10.2134/agronj1967.00021962005900050024x

13. Influence of Nitrogen and Potassium on Variations in Content of Malate, Citrate, and Malonate in Non-Nodulating Soybeans (Glycine max)

Author:
H. E. Pattee; M. R. Teel
Source:
Agronomy journal 1967 v.59 no.2 pp. 187-189
ISSN:
0002-1962
Subject:
Glycine max; acetyl coenzyme A; acidity; agronomy; citrates; malates; metabolism; nitrogen; nonprotein nitrogen; potassium
Abstract:
... The influence of nitrogen and potassium on metabolism in non-nodulating soybeans was studied. Nonprotein nitrogen was increased by high nitrogen rates but markedly reduced with increasing potassium levels. Malate decreased with increased potassium at low nitrogen fertility but increased at high nitrogen fertility. Citrate was reduced by additional potassium, irrespective of nitrogen level. Malonat ...
DOI:
10.2134/agronj1967.00021962005900020020x

14. Uses of Metalizable Dyes to Minimize the Phosphate Sorption of Cecil Soil

Author:
K. S. LaFleur; G. R. Craddock
Source:
Soil Science Society of America journal 1967 v.31 no.3 pp. 324-327
ISSN:
0361-5995
Subject:
anions; citrates; dyes; phosphates; quercetin; soil; soil solution; sorption; water soluble phosphates
Abstract:
... Native phosphate and added water-soluble phosphate are “immobilized” to a high degree by Cecil soil. Addition of high-affinity anions (e.g., citrate and humate ions) which compete with the phosphate anion for cationic soil sites reduces the amount of phosphate immobilized by Cecil soil and increases the amount of phosphate in the soil solution. Quercetin, Gallein, and Mordant Violet 39 (anionic me ...
DOI:
10.2136/sssaj1967.03615995003100030013x

15. Desorption of Phosphate from Kaolinite by Citrate and Bicarbonate

Author:
S. Nagarajah; A. M. Posner; J. P. Quirk
Source:
Soil Science Society of America journal 1968 v.32 no.4 pp. 507-510
ISSN:
0361-5995
Subject:
adsorption; bicarbonates; chlorides; citrates; clay; desorption; ionic strength; kaolinite; pH; phosphates
Abstract:
... Phosphate which cannot be desorbed from kaolinite by chloride at the same pH and ionic strength at which adsorption took place is significantly desorbed by citrate and bicarbonate. In the presence of citrate or bicarbonate, phosphate adsorption by kaolinite is reduced. The extent of reduction depends on the way in which phosphate and citrate or bicarbonate are added to the clay. Maximum reduction ...
DOI:
10.2136/sssaj1968.03615995003200040025x

16. Determination of Silica in Citrate-Bicarbonate-Dithionite Extracts of Soils

Author:
R. M. Weaver; J. K. Syers; M. L. Jackson
Source:
Soil Science Society of America journal 1968 v.32 no.4 pp. 497-501
ISSN:
0361-5995
Subject:
absorbance; aluminum; aluminum oxide; citrates; dithionite; drainage; ferric oxide; iron; molybdates; montmorillonite; silica; silicic acid; silicon; soil; soil parent materials; tartaric acid; water solubility
Abstract:
... A procedure was developed for the determination of Si directly in citrate-dithionite extracts of soils. The procedure, which provides for noninterference by citrate, dithionite, Fe, and P was developed for measurement of the absorbance of the reduced β-molybdosilicic acid in the working range of 5 to 25 µg of Si in 50 ml. Interference by unoxidized dithionite was eliminated by bubbling air through ...
DOI:
10.2136/sssaj1968.03615995003200040023x

17. Fractionation of Phosphorus in Lake Sediments: Analytical Evaluation

Author:
C. R. Frink
Source:
Soil Science Society of America journal 1969 v.33 no.2 pp. 326-328
ISSN:
0361-5995
Subject:
citrates; fractionation; inorganic phosphorus; iron; lakes; organic matter; oxidation; potassium permanganate; sediments; soil
Abstract:
... Methods for the fractionation of P in soils were evaluated in the fractionation of P in lake sediments. Both Al-P and Fe-P may be determined readily and precisely by the Chang and Jackson procedure. Reductant-soluble P was more difficult: modifications of a citrate oxidation procedure utilizing KMnO₄ produced an acceptable method. Large amounts of Fe in the Ca-P extracts caused low results, but th ...
DOI:
10.2136/sssaj1969.03615995003300020046x

18. Further Characterization of Iron Uptake in Two Genotypes of Corn

Author:
J. C. Brown; J. E. Ambler
Source:
Soil Science Society of America journal 1970 v.34 no.2 pp. 249-252
ISSN:
0361-5995
Subject:
Zea mays; calcium carbonate; citrates; corn; culture media; homozygosity; iron; leaves; nutrient solutions; pH; roots; sap
Abstract:
... Two genotypes of corn, (Zea mays L.) homozygous yellow stripe ys₁/ys₁ (Fe-inefficient) and Pa 54 (Fe-efficient), were grown in nutrient solution with two levels of CaCO₃ using two plant populations. The nutrient solution and plant population were varied to evaluate and compare the two genotypes relative to modifications in their growth medium favorable to Fe transport. Plant factors recognized as ...
DOI:
10.2136/sssaj1970.03615995003400020021x

19. An Application of Autoradiography to Study the Spacial Distribution of 33P-Labelled Orthophosphate Added to Soil Crumbs

Author:
T. D. Evans; J. K. Syers
Source:
Soil Science Society of America journal 1971 v.35 no.6 pp. 906-909
ISSN:
0361-5995
Subject:
autoradiography; bicarbonates; chlorides; citrates; desorption; energy; orthophosphates; phosphorus; soil; sorption; stable isotopes; sulfates
Abstract:
... The penetration of orthophosphate (P) into soil crumbs was studied semiquantitatively using ³¹P, the low energy isotope ³³P, autoradiography on a medium grained film, and solution analysis. Sorption of added P by the soil crumbs was rapid and was followed by penetration. Phosphate was not concentrated in discrete areas, suggesting that it was retained by a sorption rather than a precipitation mech ...
DOI:
10.2136/sssaj1971.03615995003500060019x

20. Fractionation of Inorganic Phosphate in Calcareous Lake Sediments

Author:
J. D. H. Williams; J. K. Syers; R. F. Harris; D. E. Armstrong
Source:
Soil Science Society of America journal 1971 v.35 no.2 pp. 250-255
ISSN:
0361-5995
Subject:
aluminum; calcareous soils; calcium; calcium carbonate; citrates; fluorides; fractionation; hydrochloric acid; inorganic phosphorus; iron; iron oxides; lakes; orthophosphates; sediments; sodium hydroxide; Wisconsin
Abstract:
... Inorganic orthophosphate (inorganic P) added with NH₄F reagent to calcareous Wisconsin lake sediments was recovered in the NH₄F (0–32%), citrate-dithionite-bicarbonate (18–23%), and first HCl (38–63%) reagents of an inorganic P fractionation scheme. Calcium fluoride, formed during NH₄F extraction of calcareous materials, sorbed inorganic P, presumably resulting in the formation of a CaF₂-orthophos ...
DOI:
10.2136/sssaj1971.03615995003500020023x