| |
|
|
|
Registro Completo |
|
Biblioteca(s): |
Embrapa Gado de Corte; Embrapa Mandioca e Fruticultura; Embrapa Solos. |
|
Data corrente: |
13/11/1997 |
|
Data da última atualização: |
15/01/2014 |
|
Autoria: |
VOLKWEISS, S. J. |
|
Título: |
factors affecting phosphate sorption by soils and minerals. |
|
Ano de publicação: |
1973 |
|
Fonte/Imprenta: |
University of Wisconsin, 1973. |
|
Idioma: |
Inglês
Português |
|
Notas: |
Tese Doutorado. |
|
Conteúdo: |
The objectives of this research were to study the P sorption characteristics of soils and the effects of pH and of cation type and concentration on P sorption by soils and minerals. In an attempt to characterize the nature and properties of P sorption sites of soils, P sorption isotherms in a 0.1 N NaC1 system were obtained for six limed and unlimed agricultural soils from Rio Grande do Sul, Brazil. The equilibration time was 48 hours and the concentration of P in the final solution varied from near zero to 20 ugP/ml. Langmuir plots (c/x vs c) of the data resulted in curvilinear and/or multi-straight line relationships suggesting the presence of 2 or more populations of sites with different affinities for P. An iterative multiple regression analysis computer program that assumes that each population of site follows the Langmuir equation was used to analyze the sorption data. Three populations of sites with different affinities for P were detected and the Langmuir constants, k (binding energy term) and b (sorption maximum) were estimated for each population of sites. The median and range for values of k (ml/ug P) and b (ugP/g) for the three populations of site were in decreasing order of affinity for P:K1 = 140, (40-2870) and b1=120 (8-370); K2=2.4, (0.63-10) and b2=174, (25-704); and K3 =0.095, (0.051-0.27) and b3=763 (131-1460). On the average, the total number of P sorption sites (total) was made up of 10% of sites with high affinity for P, 22% with moderate and 68% with low affinity.............................. MenosThe objectives of this research were to study the P sorption characteristics of soils and the effects of pH and of cation type and concentration on P sorption by soils and minerals. In an attempt to characterize the nature and properties of P sorption sites of soils, P sorption isotherms in a 0.1 N NaC1 system were obtained for six limed and unlimed agricultural soils from Rio Grande do Sul, Brazil. The equilibration time was 48 hours and the concentration of P in the final solution varied from near zero to 20 ugP/ml. Langmuir plots (c/x vs c) of the data resulted in curvilinear and/or multi-straight line relationships suggesting the presence of 2 or more populations of sites with different affinities for P. An iterative multiple regression analysis computer program that assumes that each population of site follows the Langmuir equation was used to analyze the sorption data. Three populations of sites with different affinities for P were detected and the Langmuir constants, k (binding energy term) and b (sorption maximum) were estimated for each population of sites. The median and range for values of k (ml/ug P) and b (ugP/g) for the three populations of site were in decreasing order of affinity for P:K1 = 140, (40-2870) and b1=120 (8-370); K2=2.4, (0.63-10) and b2=174, (25-704); and K3 =0.095, (0.051-0.27) and b3=763 (131-1460). On the average, the total number of P sorption sites (total) was made up of 10% of sites with high affinity for P, 22% with moderate and 68% with l... Mostrar Tudo |
|
Palavras-Chave: |
Solos. |
|
Thesagro: |
Fertilidade; Física; Química. |
|
Categoria do assunto: |
-- |
|
Marc: |
LEADER 01965nam a2200169 a 4500
001 1321690
005 2014-01-15
008 1973 bl uuuu m 00u1 u #d
100 1 $aVOLKWEISS, S. J.
245 $afactors affecting phosphate sorption by soils and minerals.
260 $aUniversity of Wisconsin$c1973
500 $aTese Doutorado.
520 $aThe objectives of this research were to study the P sorption characteristics of soils and the effects of pH and of cation type and concentration on P sorption by soils and minerals. In an attempt to characterize the nature and properties of P sorption sites of soils, P sorption isotherms in a 0.1 N NaC1 system were obtained for six limed and unlimed agricultural soils from Rio Grande do Sul, Brazil. The equilibration time was 48 hours and the concentration of P in the final solution varied from near zero to 20 ugP/ml. Langmuir plots (c/x vs c) of the data resulted in curvilinear and/or multi-straight line relationships suggesting the presence of 2 or more populations of sites with different affinities for P. An iterative multiple regression analysis computer program that assumes that each population of site follows the Langmuir equation was used to analyze the sorption data. Three populations of sites with different affinities for P were detected and the Langmuir constants, k (binding energy term) and b (sorption maximum) were estimated for each population of sites. The median and range for values of k (ml/ug P) and b (ugP/g) for the three populations of site were in decreasing order of affinity for P:K1 = 140, (40-2870) and b1=120 (8-370); K2=2.4, (0.63-10) and b2=174, (25-704); and K3 =0.095, (0.051-0.27) and b3=763 (131-1460). On the average, the total number of P sorption sites (total) was made up of 10% of sites with high affinity for P, 22% with moderate and 68% with low affinity..............................
650 $aFertilidade
650 $aFísica
650 $aQuímica
653 $aSolos
Download
Esconder MarcMostrar Marc Completo |
|
Registro original: |
Embrapa Gado de Corte (CNPGC) |
|
|
Biblioteca |
ID |
Origem |
Tipo/Formato |
Classificação |
Cutter |
Registro |
Volume |
Status |
URL |
Voltar
|
|
|
| Registros recuperados : 7 | |
| Registros recuperados : 7 | |
|
| Nenhum registro encontrado para a expressão de busca informada. |
|
|
