Optimizing available phosphorus in calcareous soils fertilized with diammonium phosphate and phosphoric acid using Freundlich adsorption isotherm.
ScientificWorldJournal
; 2013: 680257, 2013.
Article
em En
| MEDLINE
| ID: mdl-24307878
ABSTRACT
In calcareous soils, phosphorus (P) retention and immobilization take place due to precipitation and adsorption. Since soil pH is considered a major soil variable affecting the P sorption, an acidic P fertilizer could result in low P adsorption compared to alkaline one. Therefore, P adsorption from DAP and phosphoric acid (PA) required to produce desired soil solution P concentration was estimated using Freundlich sorption isotherms. Two soils from Faisalabad and T. T. Singh districts were spiked with 0, 10, and 20 % CaCO3 for 15 days. Freundlich adsorption isotherms (P = aC(b/a)) were constructed, and theoretical doses of PA and DAP to develop a desired soil solution P level (i.e., 0.20 mg L(-1)) were calculated. It was observed that P adsorption in soil increased with CaCO3. Moreover, at all the levels of CaCO3, P adsorption from PA was lower compared to that from DAP in both the soils. Consequently, lesser quantity of PA was required to produce desired solution P, 0.2 mg L(-1), compared to DAP. However, extrapolating the developed relationship between soil CaCO3 contents and quantity of fertilizer to other similar textured soils needs confirmation.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Fosfatos
/
Fósforo
/
Solo
/
Carbonato de Cálcio
/
Adjuvante de Freund
/
Fertilizantes
/
Modelos Químicos
Tipo de estudo:
Prognostic_studies
Idioma:
En
Ano de publicação:
2013
Tipo de documento:
Article