Phosphorus forms in cultivated indian black earth (anthrosols) of varying texture in the Brazilian Amazon.

• Autor(a) principal: SOUZA, K. W. de
• Data de Publicação: 2009
• Outros Autores: LIMA, H. N., SCHAEFER, C. E. G. R., TEIXEIRA, W. G., PULROLNIK, K., CORRÊA, G. R.
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Institucional da EMBRAPA (Repository Open Access to Scientific Information from EMBRAPA - Alice)
• Texto Completo: http://www.alice.cnptia.embrapa.br/alice/handle/doc/577957
• topic: Amazônia Brasileira; Amazon black earth; Soil P fractionation; Amazon soils; Anthropogenic soils; Solo; Fósforo; Química; Textura; Anthrosols; soil; terra preta; soil chemistry; upland soils

Despite the agricultural importance of India Black Earth (IBE) in the Amazon region, there are few studies that report on the relation between soil texture and chemical fertility of IBE. These soils of pre-Colobian origin, with high contents of P, Ca and other nutrients are found across the Amazon valley. IBE profiles were studied to evaluate the total contents of P, its primary chemical forms and the P transformation phases in areas with IBE soils of variable texture and in adjacent reference soils. The soil texture strongly influenced soil fertility, changing in terms of transformation of the primary P forms and, consequently, predominant P forms in IBE. Soils with texture varying between clay and heavy clay had higher total P contents and primary Ca-P forms. Highest P-Al and lowest total P amounts werw observed at the site Rio Preto da Eva, where texture varies from sandy, loam to sandy clay loam. In the IBE with clay texture the amounts of soluble P, extracted with NH4CI were highest, although different from Mehlich 1-extractable amounts.