Download or read book The Effect of Particle Size on the Fixation and Availability of Phosphate Fertilizers in Soils Differing in Reaction written by Malcolm Walker Wilding and published by . This book was released on 1949 with total page 152 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Availability of Rock Phosphate Fertilizer as Affected by Particle Size Incubation and Soil Reaction written by Lloyd L. Joos and published by . This book was released on 1949 with total page 128 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Water Solubility of Phosphate Fertilizers written by Orvis P. Engelstad and published by . This book was released on 1993 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Effects of Water soluble Phosphorus Content and Granule Size of Mixed Fertilizers on Phosphorus Availability to Plants written by Lowell Davis Owens and published by . This book was released on 1955 with total page 148 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Proceedings written by Soil Science Society of America and published by . This book was released on 1968 with total page 984 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Particle size Effects of Water soluble Phosphate Fertilizer written by George Robert Burns and published by . This book was released on 1962 with total page 270 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Effect of Sulfur and Manure on Availability of Rock Phosphate in Soil written by Percy Edgar Brown and published by . This book was released on 1917 with total page 40 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Movement Fixation and Availability of Phosphates in Relation to Permanent Pasture Fertilization written by Alvin Rees Midgley and published by . This book was released on 1929 with total page 120 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Residual Effects of Phosphate Fertilizers written by Ivor Keith Edwards and published by . This book was released on 1963 with total page 152 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Effects of Particle Size on the Properties and Efficiency of Fertilizers written by and published by . This book was released on 1935 with total page 32 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Effect of Phosphate Rock Particle Size on Recovery of Uranium from Superphosphate written by William Wayne Davis and published by . This book was released on 1955 with total page 32 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Fertilizer Abstracts written by and published by . This book was released on 1969 with total page 514 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Phosphate Fixation and the Response of Maize to Fertilizer Phosphate in Kenyan Soils written by D. v. d EIJK and published by . This book was released on 1997 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: In tropical soils, plant growth is often limited by a low P availability. In addition, these soils often have high P-fixation capacities due to high amounts of iron and aluminum oxyhydroxides. Furthermore, small-scale farming systems in which subsistence crops are produced for local markets are common in the tropics. Such conditions exit in South West Kenya, in the Kish area, where this study was carried out. The overall aim of the study was to improve our understanding of fertilizer P - soil - maize crop interactions and, hereby, to increase the yield response and improve the P recovery and utilization in plants. Initial and residual yield responses to fertilizer P applications; P uptake in plants, as well as P distribution and utilization within the plants; apparent fertilizer P recovery; and dissolution, transport and sorption of fertilizer P in the soils were studied under field conditions during three successive growing seasons. This was done within the concept of the low-input strategy, whereby the high-input strategy was used as a reference. The soils were classified as Ultisols and Mollisols, or as Nitisols and Luvic Phaeozems. They were low in available native P (P-Olsen 1.6 to 3.2 mg/kg) and had medium to high P sorption capacities (445 to 870 mg/kg) measured under laboratory conditions. Total P ranged from 490 to 1,035 mg/kg. Triple superphosphate was used as P fertilizer and hybrid maize as test crop. Good initial and residual yield responses were found in all soils even at low P application rates. The concept of P-fixation, as defined in this study, was not appropriate for the soils in the Kisii area. The second 'slow' phase of the fixation process was shown to proceed at a very slow rate under field conditions. Thus, P fixation is much less of a problem for farmers than expected. When P limited grain yield, the relationship between grain yield (z) and P in plant (y) could be described by the equation: z=620(y-0.50). The efficiency of utilization increased with P application to about 550 kg/kg at P rates of 22 to 131 kg/ha and decreased at higher rates due to a luxurious P uptake. Granular fertilizer residues with P in the form of Fluorapatite, Brushite and an amorphous P compound could be recovered in the soil until the end of the trials, about 600 days after application. Fertilizer P was retained in the soil immediately surrounding the residual fertilizer granules to total P values up to > 8,000 mg/kg, which was much higher than predicted from the P-sorption studies in the laboratory. Available P levels (P-Olsen) in the P-enriched soil volume were high, up to > 800 mg/kg. The available fertilizer P fraction (P-Olsen/P total) remained fairly constant with time. It was suggested that the number of roots, i.e. root surface area, present in the small P-enriched volume was the limiting factor in fertilizer P uptake. As a result, the apparent P recoveries per crop were low. They were about 10 % each growing season at a P rate of 22 kg/ha. Subseed placement at the start of each growing season is recommended, either placed alone or together with small amounts of cow dung. Then, plants benefit highly from both the startereffect of freshly-applied fertilizer and the residual effect of previously-applied (residual) fertilizer. P application rates of 20 to 40 kg/ha (in P2O5: 45 to 90 kg/ha) are advised for maize. At these rates, slightly more P is applied than plants require for producing maximum grain yields and the P availability of the soils will gradually increase by enlarging the soil volume enriched with fertilizer P. This repeated subseed placement fits in well with the low-input strategy and is probably easily adaptable in tropical small-scale farming systems.

Download or read book Iowa State College Journal of Science written by and published by . This book was released on 1950 with total page 632 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Superphosphate written by Keith Stanley Mayberry and published by . This book was released on 1967 with total page 88 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 1974 with total page 528 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Phosphate in Soils written by H. Magdi Selim and published by CRC Press. This book was released on 2018-10-08 with total page 381 pages. Available in PDF, EPUB and Kindle. Book excerpt: Edited by One of the Best Specialists in Soil Science Recent studies reveal that Phosphorus (P) in the form of phosphate, a macronutrient essential for plant growth, and crop yields can influence the bioavailability, retention, and mobility of trace elements, metal(loid)s, and radio nuclides in soils. When this occurs, phosphates can affect the dynamics of heavy metals and influence soil characteristics, impacting soil mobility and toxicity. Phosphate in Soils: Interaction with Micronutrients, Radionuclides and Heavy Metals utilizes the latest research to emphasize the role that phosphate plays in enhancing or reducing the mobility of heavy metals in soil, and the soil-water-plant environment. It provides an in-depth understanding of each heavy metal species, and expands on phosphate interactions in geological material. Composed of 12 chapters, this text: Provides an overview of the reactions of metal(loid)s and common P compounds that are used as fertilizer in soils Emphasizes the effect of phosphorus on copper and zinc adsorption in acid soils Discusses findings on the influence of phosphate compounds on speciation, mobility, and bioavailability of heavy metals in soils as well as the role of phosphates on in situ and phytoremediation of heavy metals for contaminated soils Places emphasis on the influence of phosphate on various heavy metals species in soils, and their solubility/mobility and availability Provides extensive information on testing various high phosphate materials for remediation of heavy metal, micronutrients, and radionuclides contaminated sites Explores the reactivity of heavy metals, micronutrients and radionuclides elements in several soils Presents a case study illustrating various remediation efforts of acidic soils and remediation of Cu, Zn, and lead (Pb) contaminated soils around nonferrous industrial plants Emphasizes the significance of common ions (cations and anions) on phosphate mobility and sorption in soils, and more The author includes analytical and numerical solutions along with hands-on applications, and addresses other topics that include the transport and sorption modeling of heavy metals in the presence of phosphate at different scales in the vadose zone.