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Adsor o de fósforo em dez solos do Estado de Pernambuco e suas rela es com parametros físicos e químicos = Phosphorus adsorption in ten soils from Pernambuco State and its relations with physical and chemical parameters
Rossini Mattos Corrêa,Clístenes Williams Araújo do Nascimento,Alexandre Tavares da Rocha
Acta Scientiarum : Agronomy , 2011,
Abstract: Um experimento foi conduzido para estudar a adsor o de fósforo (P) emamostras de dez solos do Estado de Pernambuco, Nordeste do Brasil. As rela es entre atributos físicos e químicos do solo e as isotermas de adsor o de P foram também avaliadas. Os resultados mostraram que a capacidade máxima de adsor o de fosfato (CMAP), o P-remanescente (P-rem) e a constante k de da equa o Freundlich s o variáveis confiáveis para se caracterizar a adsor o de P pelos solos. Pela sua praticidade de determina o, o Prem é a variável mais indicada. Os parametros de adsor o de P CMAP, P-rem e constante k de Freundlich apresentaram correla o (p < 0,01) com os atributos químicos acidezpotencial (H+Al), alumínio trocável (Al), capacidade de troca cati nica (CTC) e com os atributos físicos teor de argila e capacidade de campo (CC). As variáveis CC, P-rem, H+Al, Al, CTC e teor de argila, entre os atributos físicos e químicos avaliados, permitem para os solos estudados a estimativa do valor da CMAP. A energia de adsor o de fosfato e a constante n da isoterma de Freundlich n o foram indicadores confiáveis do poder de adsor o de fósforo dos solos. An experiment was carried out to study phosphorus (P) adsorption in ten soil samples from Pernambuco State, Northeastern Brazil. The relationship between physical and chemical soil attributes and P adsorption isotherms were also evaluated. The results showed that maximum phosphorus adsorption capacity (MPAC), remaining P (Rem-P) and the k constant of the Freundlich equation are reliable variables to characterize P adsorption by the soils. Due to its easy determination, Rem-P is the best indicated variable. The parameters of P adsorption MPAC, Rem-P and the k constant of the Freundlich equation showed correlation (p < 0.01) with the chemical attributes potential acidity (H+Al), exchangeable aluminum (Al), exchangeable cation capacity (ECC) and with the physical attributes clay and field capacity (FC). The variables FC, Rem-P, H+Al, Al, ECC and clay, among the chemical and physical attributes evaluated, allowed estimating the MPAC value on the studied soils. The P adsorption energy and the n constant of the Freundlich isotherm were not reliable indicators of the P soil adsorption power.
Phosphorus adsorption characteristics in paraiba state argisols, plinthite soils and cambisols, Brazil
Lucia Helena Garófalo Chaves,Iêde de Brito Chaves,Ana Kelliane Silva de Nascimento,Antonio Evami Cavalcante Sousa
Engenharia Ambiental : Pesquisa e Tecnologia , 2009,
Abstract: The objective of this paper was to determine the phosphorus (P) adsorption characteristics using the Langmuir isotherm and its relation with some chemical and physical properties of soils. The study was carried out in laboratory of Universidade Federal de Campina Grande, Paraiba State (PB), Brazil, with Argisols (PVAd; PVAe; PVd), two Plinthite soil (FTd-1 e FTd-2) and three Cambisols (CXbd-1; CXbd-2; CXbe) surface (0-20 cm) samples from Paraíba State. In these soils, remaining phosphorus was determined with a solution containing 60 mg L-1 of P. The phosphorus doses used were defined based on the remaining P values and corresponded to 10; 30; 50; 100 e 150 mg L-1 of P. To available the maximum P adsorption capacity (MPAC), the data of adsorbed P and the concentrations of equilibrium solutions were adjusted to Langmuir isotherm. Langmuir model offered a good fit for the experimental data. The highest MPAC value was observed in PVd soil. The CMAP and adsorption energy were negatively correlated with base saturation. The attributes closest correlated with soil of the same class MPAC were soil clay and organic matter content and pH value. Available P influenced the adsorption of the element in PVAe.Key-words: Langmuir, adsorption isotherm.
Organic residue, limestone, gypsum, and phosphorus adsorption by lowland soils
Andrade, Alex Teixeira;Fernandes, Luiz Arnaldo;Faquin, Valdemar;
Scientia Agricola , 2002, DOI: 10.1590/S0103-90162002000200022
Abstract: organic residue application is a low cost alternative to reduce the use of inorganic fertilizers and correctives. in order to study the effect of organic residues, limestone and gypsum application on phosphorus adsorption by lowland soils, four experiments were carried out. a mesic organosol (oy), a melanic gleysol (mg), a haplic gleysol (gx), and a fluvic neosol (ru) were used in a completely randomized design and factorial scheme (3 x 2), with five replicates: three soil amendment practices (limestone, gypsum and no corrective) and two levels of organic residue (with and without corral manure). soil samples were incubated for 60 days, with and without organic residue incorporation. after this period, we applied the corrective and incubated the soil for 30 days, then p and basic fertilization (macro and micronutrients) were applied and the soil was incubated for additional 60 days. equilibrium phosphorus, maximum phosphate adsorption capacity, ph, exchangeable al and phosphorus-buffering index were measured. organic residue and limestone application increased soil ph and reduced exchangeable al, decreasing p adsorption. gypsum application did not increase the ph but reduced exchangeable al and p adsorption.
Organic residue, limestone, gypsum, and phosphorus adsorption by lowland soils  [cached]
Andrade Alex Teixeira,Fernandes Luiz Arnaldo,Faquin Valdemar
Scientia Agricola , 2002,
Abstract: Organic residue application is a low cost alternative to reduce the use of inorganic fertilizers and correctives. In order to study the effect of organic residues, limestone and gypsum application on phosphorus adsorption by lowland soils, four experiments were carried out. A Mesic Organosol (OY), a Melanic Gleysol (MG), a Haplic Gleysol (GX), and a Fluvic Neosol (RU) were used in a completely randomized design and factorial scheme (3 x 2), with five replicates: three soil amendment practices (limestone, gypsum and no corrective) and two levels of organic residue (with and without corral manure). Soil samples were incubated for 60 days, with and without organic residue incorporation. After this period, we applied the corrective and incubated the soil for 30 days, then P and basic fertilization (macro and micronutrients) were applied and the soil was incubated for additional 60 days. Equilibrium phosphorus, maximum phosphate adsorption capacity, pH, exchangeable Al and phosphorus-buffering index were measured. Organic residue and limestone application increased soil pH and reduced exchangeable Al, decreasing P adsorption. Gypsum application did not increase the pH but reduced exchangeable Al and P adsorption.
Phosphorus Fractions and Sorption Characteristics in Selected Overfertilized Soils in Northern Iran
Hamidreza Memarian,Mehdi Emadi,Mehrdad Safaei
Research Journal of Biological Sciences , 2008,
Abstract: Characterization of Phosphorus (P) in soils is important both agronomically and environmentally, although the outcome may depend on the technique applied. Phosphorus desorption from overfertilized soils is significant for agriculture and the environmental pollution in northern Iran as in the world. Different P fractions viz. total, organic, inorganic (easily soluble P, Fe-P, Al-P, Ca-P and occluded P), PW (water extractable) and NH4-lactate extractable P (PAL) varied widely among the soils studied, indicating a wide variability of P supplying capacity of these soils. Soluble P was positively correlated to Ca-P (r = 0.7; p<0.05), PW (r = 0.68; p<0.05) and pH (r = 0.6; p<0.05). Iron-P was only positively related to Alo (r = 0.67; p<0.05), whereas it was not related to any of the other parameters tested. The PAL was highly correlated with PW (r = 0.82; p<0.01), Ca-P (r = 0.69; p<0.05), total P (r = 0.75; p<0.05), inorganic P (r = 0.81; p<0.01) and pH (r = 0.83; p<0.01). Results indicated that Freundlich equation gave a better fit of the equilibrium P sorption data than did the Langmuir equations. However, adsorption data fitted approximately well to the Langmuir equation for most soils. The P affinity constant (K), adsorption maximum (b) and thus maximum buffering capacity (MPBC) and adsorption isotherm of P were highest in the sandy clay soil from Jamaleddinkola, which also contained high amounts of Fe, Al and clay particles and the lowest in sandy soil from Deseleh, which contained very high initial PAL and the lowest content of Fe, Al, silt and clay among all the soils studied. The P affinity constant (K) was correlated positively and significantly to clay content (r = 0.67; p<0.05). Whereas, MPBC was correlated positively and significantly to clay content (r = 0.65; p<0.05) and Feo(r = 0.63; p<0.05). The results from this investigation give useful data to the work for optimizing P supply and to minimize P runoff. A positive correlation between equilibrium P concentration and PAL can be used to estimate the potential environmental risk related to a high soil P level.
Mutual Adsorption of Lead and Phosphorus onto Selected Soil Clay Minerals  [PDF]
Mohammed Abdalla Elsheikh, Pardon Muchaonyerwa, Erni Johan, Naoto Matsue, Teruo Henmi
Advances in Chemical Engineering and Science (ACES) , 2018, DOI: 10.4236/aces.2018.82005
Abstract:
Mutual adsorption of lead (Pb) and phosphorus (P) at pH 5 onto three soil clays materials (kaolinite, montmorillonite, and allophane) was studied to know interaction of the anion and the cation at surface of the clays. Adsorption of Pb was determined on montmorillonite, kaolinite and allophane with the following pretreatments; 1) untreated clay (control), 2) phosphate treated clay (P-clay) and 3) clay pre-treated with both P and Pb (P-Pb-clay). Adsorption of P was determined on montmorillonite, kaolinite and allophane with the following pretreatments; 1) control 2) Pb treated clay (Pb-clay) and 3) P-Pb-clay. The adsorption of Pb on the untreated clays was in the order: montmorillonite > allophane > kaolinite. On allophane and kaolinite Pb adsorption was in the order P-clay > P-Pb-clay > control. For montmorillonite, the trend was: P-Pb-clay = control > P-clay. Phosphorus adsorption was in the order Pb-clay = P-Pb-clay > control for montmorillonite and kaolinite, Pb-clay > control > P-Pb-clay for allophane. The findings suggested that pre-treatment with phosphate increases Pb adsorption on kaolinite and allophane, and decrease on montmorillonite, while pretreatment with Pb increases phosphate sorption on all clays, and both Pb and P increased adsorption on montmorillonite and kaolinite and decrease on allophane.
Study on adsorption and desorption characteristics of soils and phosphorus requirement under oxidized and reduced conditions
氧化还原条件下红壤磷吸附与解吸特性及需磷量探讨

SHAO Xing-hu,ZHANG Jian-zhong,MAO Yong,WANG Zhong-min,
邵兴华
,张建忠,毛 勇,王中敏

土壤 , 2010,
Abstract: Phosphate requirement of paddy or upland were investigated by adsorption/desorption experiment under oxidized and reduced conditions in five red soils. Results showed that P adsorption capacity increased with the increase of added P concentration. Phosphate adsorption curves of soils fitted well with Langmuir equation. The range of the maximum capacities of P adsorption (Qm) ranged from 794.22 to 956.75 mg/kg under oxidized condition and from 867.31 to 1 195.62 mg/kg under reduced condition. The capacity of desorption P increased with the increase of the capacity of P adsorption, P desorption rate of soils was lower under reduced condition than that under oxidized condition. Phosphorus requirement was calculated from the Langumir equation on the basis of P concentration in soil solution at 0.2 mg/kg. Phosphorus requirement of soils increased after water logging.
Remaining phosphorus and sodium fluoride pH in soils with different clay contents and clay mineralogies
Alves, Marcelo Eduardo;Lavorenti, Arquimedes;
Pesquisa Agropecuária Brasileira , 2004, DOI: 10.1590/S0100-204X2004000300006
Abstract: the remaining phosphorus (prem) has been used for estimating the phosphorus buffer capacity (pbc) of soils of some brazilian regions. furthermore, the remaining phosphorus can also be used for estimating p, s and zn soil critical levels determined with pbc-sensible extractants and for defining p and s levels to be used not only in p and s adsorption studies but also for the establishment of p and s response curves. the objective of this work was to evaluate the effects of soil clay content and clay mineralogy on prem and its relationship with ph values measured in saturated naf solution (ph naf). ammonium-oxalate-extractable aluminum exerts the major impacts on both prem and ph naf, which, in turn, are less dependent on soil clay content. although prem and ph naf have consistent correlation, the former has a soil-pbc discriminatory capacity much greater than ph naf.
Effects of flooding on iron transformation and phosphorus adsorption - desorption properties in different layers of the paddy soils
水稻土淹水过程中不同土层铁形态的变化及对磷吸附解吸特性的影响

SU Ling,LIN Xian yong,ZHANG Yong song,YANG Yu ai,
苏玲
,林咸永,章永松,杨玉爱

浙江大学学报(农业与生命科学版) , 2001,
Abstract: A soil column simulated experiment was carried out to estimate the effect of flooding on iron transformation and phosphorus adsorption desorption properties in different layers of the paddy soils The results showed that the content of amorphous Fe oxides of the soils increased significantly with the decreasing of crystalline Fe oxides content during the flooding process, and the maximum capacity of P adsorption increased remarkably, while desorbed P/adsorbed P ratio decreased More notable changes of Fe forms and phosphorus adsorption and desorption properties were observed in the reduced layer of Ultisol, compared with those in the oxidized layer But there was no significant difference between the two layers in Entisol
Relation between Fe-oxides transformation and phosphorus adsorption in the oxic and anoxic layers of two paddy soils as affected by flooding
淹水对两种水稻土氧化层和还原层铁氧化物转化和磷吸附的影响

Abstract,
章永松
,林咸永

浙江大学学报(农业与生命科学版) , 2002,
Abstract: The changes of total reducing substances (TRS), oxalate extractable Fe (Fe o), dithionite citrate bicarbonate extractable Fe (Fe DCB ) and phosphorus adsorption (P adsorption) in oxic and anoxic layers of two paddy soils during 6 week flooding were examined under laboratory conditions. It was found that TRS, Fe o, and P adsorption in fresh samples were sharply increased by flooding, and significantly higher in anoxic layers than in oxic layers of the submerged soils. The significant correlation (at 1% level) between TRS, Fe o and P adsorption suggested that the substantial increase of P adsorption caused by flooding was ascribed to the reducing process of soil Eh resulting from flooding, transformation of Fe DCB to Fe o, and poor crystallinity of soil iron oxide induced by low Eh.
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