Consulta: subjectFacets:"Phosphorus fractionation"
Registros recuperados: 11
Data/hora: 12/06/2024 14:25:06

Organic compounds from plant extracts and their effect on soil phosphorus availability
Provedor de dados: 86
Autores: Pavinato,Paulo Sergio; Merlin,Alexandre; Rosolem,Ciro Antonio.
The objective of this work was to evaluate the effect of organic compounds from plant extracts of six species and phosphate fertilization on soil phosphorus availability. Pots of 30 cm height and 5 cm diameter were filled with Typic Hapludox. Each pot constituted a plot of a completely randomized design, in a 7x2 factorial arrangement, with four replicates. Aqueous extracts of black oat (Avena strigosa), radish (Raphanus sativus), corn (Zea mays), millet (Pennisetum glaucum), soybean (Glycine max), sorghum (Sorghum bicolor), and water, as control, were added in each plot, with or without soluble phosphate fertilization. After seven days of incubation, soil samples were taken from soil layers at various depths, and labile, moderately labile and nonlabile P...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Raphanus sativus; Cover crops; Crop rotation; Labile phosphorus; Low-molecular-weight organic acids; Phosphorus fractionation.
Ano: 2008
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-204X2008001000017

Ruzigrass affecting soil-phosphorus availability
Provedor de dados: 86
Autores: Merlin,Alexandre; He,Zhenli Li; Rosolem,Ciro Antonio.
The objective of this work was to evaluate the effectiveness of ruzigrass (Urochloaruziziensis) in enhancing soil-P availability in areas fertilized with soluble or reactive rock phosphates. The area had been cropped for five years under no-till, in a system involving soybean, triticale/black-oat, and pearl millet. Previously to the five-year cultivation period, corrective phosphorus fertilization was applied once on soil surface, at 0.0 and 80 kg ha-1 P2O5, as triple superphosphate or Arad rock phosphate. After this five-year period, plots received the same corrective P fertilization as before and ruzigrass was introduced to the cropping system in the stead of the other cover crops. Soil samples were taken (0-10 cm) after ruzigrass cultivation and...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Brachiaria ruziziensis; Urochloa ruziziensis; Cover crops; Crop rotation; P cycling; Phosphorus fractionation.
Ano: 2013
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-204X2013001200007

Soil phosphorus dynamics and availability and irrigated coffee yield
Provedor de dados: 90
Autores: Reis,Thiago Henrique Pereira; Guimarães,Paulo Tácito Gontijo; Furtini Neto,Antônio Eduardo; Guerra,Antônio Fernando; Curi,Nilton.
Research data have demonstrated that the P demand of coffee (Coffea arabica L.) is similar to that of short-cycle crops. In this context, the objective of this study was to evaluate the influence of annual P fertilization on the soil P status by the quantification of labile, moderately labile, low-labile, and total P fractions, associating them to coffee yield. The experiment was installed in a typical dystrophic Red Latosol (Oxisol) cultivated with irrigated coffee annually fertilized with triple superphosphate at rates of 0, 50, 100, 200, and 400 kg ha-1 P2O5. Phosphorus fractions were determined in two soil layers: 0-10 and 10-20 cm. The P leaf contents and coffee yield in 2008 were also evaluated. The irrigated coffee responded to phosphate...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Coffee arabica L.; Phosphate fertilization; Phosphorus fractionation.
Ano: 2011
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832011000200019

Phosphorus transformation in poultry litter and litter-treated Oxisol of Brazil assessed by 31P-NMR and wet chemical fractionation
Provedor de dados: 90
Autores: Souza,César Roriz de; Ghosh,Amlan Kumar; Silva,Ivo Ribeiro da; Alvarenga,Elson Santiago de; Novais,Roberto Ferreira; Jesus,Guilherme Luiz de.
Large quantities of poultry litter are being produced in Brazil, which contain appreciable amounts of phosphorus (P) that could be of environmental concern. To assess the immediate environmental threat, five poultry litters composed of diverse bedding material were incubated for 43 days under greenhouse conditions. The litters consisted of: coffee bean husk (CH); wood chips (WC); rice husk (RH); ground corn cobs (CC) and ground napier grass (NG) (Pennisetum purpureum Schum.), in which the change in forms of soluble P was evaluated using 31P NMR spectroscopy. On average, 80.2 and 19.8 % of the total P in the extract, respectively, accounted for the inorganic and organic forms before incubation and 48 % of the organic P was mineralized to inorganic P in 43...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Pyrophosphates; Organic phosphorus; Phosphorus fractionation; Bedding material.
Ano: 2012
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832012000500016

Congo grass grown in rotation with soybean affects phosphorus bound to soil carbon
Provedor de dados: 90
Autores: Merlin,Alexandre; He,Zhenli L.; Rosolem,Ciro Antonio.
The phosphorus supply to crops in tropical soils is deficient due to its somewhat insoluble nature in soil, and addition of P fertilizers has been necessary to achieve high yields. The objective of this study was to examine the mechanisms through which a cover crop (Congo grass - Brachiaria ruziziensis) in rotation with soybean can enhance soil and fertilizer P availability using long-term field trials and laboratory chemical fractionation approaches. The experimental field had been cropped to soybean in rotation with several species under no-till for six years. An application rate of no P or 240 kg ha-1 of P2O5 had been applied as triple superphosphate or as Arad rock phosphate. In April 2009, once more 0.0 or 80.0 kg ha-1 of P2O5 was applied to the same...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Crop rotation; No-till; Organic P; Phosphorus fractionation.
Ano: 2014
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832014000300020

Phosphorus Forms in Sediments as Indicators of Anthropic Pressures in an Agricultural Catchment in Southern Brazil
Provedor de dados: 90
Autores: Tiecher,Tales; Schenato,Ricardo Bergamo; Santanna,Maria Alice; Caner,Laurent; Santos,Danilo Rheinheimer dos.
ABSTRACT Phosphorus (P) fractionation is a suitable procedure to ascertain P lability in sediments and is able to distinguish sources of P under different soil management practices in a catchment. Brazil is the second largest producer and the largest exporter of tobacco in the world. Inadequate management of cultivated areas exposes the soil to erosion processes, accelerating the transfer of sediment and P to water bodies, which leads to eutrophication. We evaluated the P forms in suspended sediments collected at two rainfall events in the stream of a small catchment in the state of Rio Grande do Sul. The samples were collected upstream and downstream areas in three sub-catchments with different degrees of anthropogenic pressure and in three phases of the...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Phosphorus fractionation; Watershed; Nonpoint source pollution; Eutrophication; Land use.
Ano: 2017
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832017000100431

Forms of inorganic phosphorus in soil under different long term soil tillage systems and winter crops
Provedor de dados: 90
Autores: Tiecher,Tales; Santos,Danilo Rheinheimer dos; Kaminski,João; Calegari,Ademir.
The cultivation of crops with different capacity of P uptake and use under long-term soil tillage systems can affect the distribution of P cycling and inorganic forms in the soil, as a result of higher or lower use efficiency of P applied in fertilizers. The purpose of this study was to evaluate the effect of long-term cultivation of different winter species under tillage systems on the distribution of inorganic P forms in the soil. In 1986, the experiment was initiated with six winter crops (blue lupin, hairy vetch, oat, oilseed radish, wheat and fallow) on a Rhodic Hapludox in southwestern Paraná, under no-tillage (NT) and conventional tillage (CT). The application of phosphate fertilizer in NT rows increased inorganic P in the labile and moderately...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: No tillage; Conventional tillage; Lability; Phosphorus fractionation; Cover crops; Soil management.
Ano: 2012
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832012000100028

Animal manure phosphorus characterization by sequential chemical fractionation, release kinetics and 31P-NMR analysis
Provedor de dados: 90
Autores: Tiecher,Tales; Zafar,Mohsin; Mallmann,Fábio Joel Kochem; Bortoluzzi,Edson Campanhola; Bender,Marcos Antonio; Ciotti,Lucas Henrique; Santos,Danilo Rheinheimer dos.
Phosphate release kinetics from manures are of global interest because sustainable plant nutrition with phosphate will be a major concern in the future. Although information on the bioavailability and chemical composition of P present in manure used as fertilizer are important to understand its dynamics in the soil, such studies are still scarce. Therefore, P extraction was evaluated in this study by sequential chemical fractionation, desorption with anion-cation exchange resin and 31P nuclear magnetic resonance (31P-NMR) spectroscopy to assess the P forms in three different dry manure types (i.e. poultry, cattle and swine manure). All three methods showed that the P forms in poultry, cattle and swine dry manures are mostly inorganic and highly...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Organic amend; Phosphorus bioavailability; Phytate; Phosphorus fractionation.
Ano: 2014
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832014000500016

Bioavailability of phosphorus from composts and struvite in acid soils
Provedor de dados: 91
Autores: Horta,Carmo.
ABSTRACT The objective of this study was to assess the type and fractions of phosphorus (P) forms in composts and struvite and how these P forms affect the bioavailability of P in the soil. P fertilization was performed with compost from sewage sludge (CSS), compost from poultry litter (CPL) and struvite (SV) and compared with single superphosphate (SSP). P forms were quantified through a sequential fractionation scheme. The first extraction was performed with H2O, the second with 0.5 M NaHCO3, the third with 0.1 M NaOH and the fourth with 1 M HCl. The release of P over time, after soil P fertilization, was assessed by incubating the fertilizers with a low-P acid soil. P bioavailability was assessed through a micro-pot experiment with the incubated soils...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Olsen P; Phosphorus fractionation; Phosphorus sustainability; Phosphorus use efficiency.
Ano: 2017
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-43662017000700459

Rhizosphere pH and phosphorus forms in an Oxisol cultivated with soybean, brachiaria grass, millet and sorghum
Provedor de dados: 63
Autores: Schoninger,Evandro Luiz; Gatiboni,Luciano Colpo; Ernani,Paulo Roberto.
Plants have shown different responses to fertilization with rock phosphate, including responses through alteration of the attributes of rhizospheric soil. The objective of this study was to evaluate soil pH alterations and alterations in the contents of forms of phosphorus in the rhizosphere of soil fertilized with rock phosphate as a result of cultivation of species of plants. An experiment was developed under greenhouse conditions to evaluate alterations in the pH and in the forms of phosphorus in the rhizosphere of an Oxisol fertilized with rock phosphate and cultivated with four species. Treatments consisted of the cultivation of four species of soybean - Glycine max (L.) Merrill, brachiaria grass - Brachiaria brizantha Hochst Stapf, millet -...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Brazilian savanna soils; Phosphorus fractionation; Cover plants; Rock phosphate; Rhizospheric soil.
Ano: 2012
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162012000400004

Phosphorus fractions in soil after successive crops of Pinus taeda L. without fertilization
Provedor de dados: 65
Autores: Gatiboni,Luciano Colpo; Vargas,Cristiane Ottes; Albuquerque,Jackson Adriano; Almeida,Jaime Antonio; Stahl,James; Chaves,Djalma Miller; Brunetto,Gustavo; Dall’Orsoletta,Daniel João; Rauber,Luiz Paulo.
ABSTRACT: Pinus cultivation without fertilization is a common practice in southern Brazil, which can induce a decline in the availability of phosphorus (P) in the soil. The purpose of this study was to evaluate the changes in phosphorus fractions in a Humic Cambisol subjected to continuous Pinus taeda L. cultivation without fertilization. Two forest stands were evaluated, after 16 years of Pinus cultivation (1st crop) and 49 years (3rd crop), when soil samples were collected (layers 0-10, 10-20, 20-40, 40-60, and 60-80cm) from six trenches per forest. In soil samples, the P contained in organic (Po) and inorganic (Pi) forms was determined by sequential chemical fractionation. Labile inorganic P fractions remained unchanged after the different cultivation...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Forest rotations; Successive crops; Phosphorus fractionation; Labile phosphorus.
Ano: 2017
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-84782017000700302