Download or read book Effect of Exchangeable Potassium Level and Drying on Release and Fixation of Potassium by Selected Kentucky Soils written by Robert H. Dowdy and published by . This book was released on 1961 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Potassium Fixation and Release in Several Agricultural Soils of Georgia written by Marcus Michael Eichhorn and published by . This book was released on 1963 with total page 370 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Factors Affecting the Availability of Potassium Through Fixation and Release in Soils of Diverse Mineralogical Composition written by Gordon Lawrence Rees and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The management of soil potassium is complicated by sorption and release of K by soil minerals, with fixation of K by vermiculite removing it from the pool of readily-available exchangeable K. Several laboratory methods have been developed to characterize different pools of soil potassium, including ammonium acetate extraction of exchangeable K (XK), sodium tetraphenylboron extraction of exchangeable and some nonexchangeable K (TPB-K), and a method to estimate the potential of soils to fix K (Kfix). In order to understand the relationship of these methods to each other and to K uptake by plants, we undertook a series of experiments to evaluate the effect of K concentration, incubation time, soil moisture content, and mineralogy on soil K pools. Additions of K equal to initially measured Kfix values only partially reduced K fixation, and increased XK and TPB-K by less than the amount of K added, indicating that some K was fixed strongly enough to be removed from the nominally plant-available pool. Duration of incubation with K from 1 to 16 days did not significantly impact K fixation or availability as measured by these methods, indicating that fixation reactions took place within the first 24 hours. Incremental additions of potassium up to an amount equal to the cation exchange capacity resulted in increasing amounts of K fixed. For some soils, a plateau was reached indicating a maximum level of K fixation, but for other soils it is unclear if a maximum was achieved. Recovery of K by the TPB-K method was roughly twice as efficient as by the XK method. Approximately 50% of fixed K was plant-available nonexchangeable K (PANK), meaning it was recovered by the TPB-K method but not by the XK method. A single air-drying event, relative to soils maintained at field-moist water content, resulted in an increase in Kfix for all K-fixing soils by an average of 55 mg kg−1, but the change in Kfix for non-K-fixing soils was not consistent. The change in Kfix was not correlated with XK values. Changes in XK with drying were less than 20 mg kg−1 for most samples, with XK increasing for most K-fixing and low-XK soils, with less consistency for high-XK soils. Multiple cycles of wetting and drying did not result in further changes in soil K measurements. In a greenhouse pot study, K uptake by annual ryegrass (Lolium multiflorum) was best correlated with TPB-K (r=0.8966), and yield was best correlated with total K by aqua regia digestion (r=0.7465) followed by TPB-K (r=0.6692). The critical value for yield response determined by the TPB-K method was most successful in predicting significant responses to increased K rates. The XK method also performed well in this respect. K fixation by one soil resulted in reduced uptake of K, and in yield responses to higher K rates than predicted by critical values for all methods. For other soils, the effect of K fixation potential was unclear. Atomic force microscopy of clay grains from selected K-fixing soils and standard clays revealed complex surface morphology for most soils which made it impossible to delineate changes in layer spacing with K sorption or release. Nearly-flat surfaces and stacks of relatively few layers in smectite clays were more conducive to this analysis. For both montmorillonite and beidellite standards, layers collapsed with displacement of Na+ by K+, and re-expanded after extraction with a TPB solution. No zones of preferential K fixation or release were observed.
Download or read book Proceedings written by Soil Science Society of America and published by . This book was released on 1967 with total page 934 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Agrochimica written by and published by . This book was released on 1976 with total page 606 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Factors Affecting the Release of Soil Potassium to Exchangeable Form on Drying written by Harry Mikio Kunishi and published by . This book was released on 1963 with total page 200 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Proceedings Soil Science Society of America written by Soil Science Society of America and published by . This book was released on 1975 with total page 720 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Report written by Kentucky Agricultural Experiment Station and published by . This book was released on 1959 with total page 580 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Factors Influencing the Levels of Exchangeable Potassium in Gilpin and Cookport Soils written by W. B. Barrett and published by . This book was released on 1973 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Abstracts of Recent Published Material on Soil and Water Conservation written by and published by . This book was released on 1961 with total page 1026 pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstracts for Dec. 1954- issued in the Agricultural Research Service's series ARS-41.
Download or read book Fixed Soil Potassium written by Kenneth Paul Dubrovin and published by . This book was released on 1956 with total page 350 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Role of Potassium in Agriculture written by Victor James Kilmer and published by . This book was released on 1968 with total page 530 pages. Available in PDF, EPUB and Kindle. Book excerpt: Potassium reserves in the world. Potassium fertlizer technology. Preparation of finished fertilizers containing potassium. Agronomic evaluatin of potassium polyphosphate and potassium calcium pyrophosphates as sources of potassium. Mineralogy of soil potassium. Role of potassium in photosynthesis and respiration. Effect of potassium on carbohydrate metabolism and translocation. The effect of potassium on the organic acid and Nonprotein nitrogen content of plant tissue. The effect of potassium and other univalent cations on the conformation of enzymes. Role of potassium in human and animal nutrition. The effects of potassium on disease resistance. Effect of potassium on Quality factors - fruits and vegetables. Soil factors affecting potassium availability. Mechanism of potassium absorption by plants. Exchangeable cations of plant roots and potassium absorption by the plant. Interaction of potassium and other ions. Plant factors affecting potassium availability and uptake. Potassium nutrition of tropical crops. Potassium nutrition of forage crops with perennials. Potassium nutrition of soybeans and corn. Potassium nutrition of tree crops. Potassium nutrition of vegetable crops.
Download or read book The Effect of Different Rates Sources and Methods of Application of Potassium Upon the Potassium Status of Some New York Soils written by Joseph Talmadge Hood and published by . This book was released on 1954 with total page 318 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Effect of Drying on Exchangeable Potassium in Soils from Illinois and Kansas written by Robert Arthur Bohannon and published by . This book was released on 1957 with total page 200 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Annual Report written by Kentucky Agricultural Experiment Station and published by . This book was released on 1956 with total page 1012 pages. Available in PDF, EPUB and Kindle. Book excerpt: 1910 includes also: Report of the director of the Kentucky agricultural experiment station to the governer of Kentucky on the enforcement of the Food and drugs act for the years 1908 and 1909.
Download or read book The Potassium Supplying Power of Some New York Soils as Determined by Laboratory and Field Tests written by Coenraad Helmich Henri ter Kuile and published by . This book was released on 1950 with total page 224 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Annual Report for the Year Ending December 31 written by Kentucky Agricultural Experiment Station and published by . This book was released on 1961 with total page 838 pages. Available in PDF, EPUB and Kindle. Book excerpt:
