Data/hora: 06/06/2024 15:12:45

Biblioteca(s): | Embrapa Cerrados; Embrapa Gado de Corte; Embrapa Solos.
Data corrente: | 11/02/1993
Data da última atualização: | 22/10/1999
Autoria: | LINS, I. D. G.
Título: | Improvement of soil test interpretations for phosphorus and zinc.
Ano de publicação: | 1987
Fonte/Imprenta: | Raleigh: North Carolina State University, 1987.
Páginas: | 317p.
Idioma: | Inglês
Notas: | Ph.D. Thesis.
Conteúdo: | Soil test interpretations may be improved by including at least one soil property in addition to the extractable nutrient concentration. This improves the accuracy of the interpretation over a range of soil conditions. Greenhouse and field studies were conducted to evaluate the best properties to include in the phosphorus soil test for soybeans [Glycine max (L.) Merr.] and zinc soil test for corn (Zea mays L. ). Properties evaluated for P were clay content, surface area, adsorption maximum, adsorption energy, buffering coefficients by three methods and quantities of specific clay types. Extractable P was also determined by four techniques; Mehlich-1, Mehlich-3, Bray-1 and Resin. Seven and five soil that varied in clay content and type were used in the greenhouse and field, respectively. Inclusion of na additional soil property related to the capacity factor improved the soil test interpretation for all the soil P tests. Clay content and surface area were the best properties to include. The P buffering coefficients also did quite well. It was noted, however, that while the interpretation could be validated on kaolinitic soils, it could not be applied to coarse textured soils in which gibbsite was the dominate clay mineral. Improved soil test interpretations for P were developed for all four extractants that could be applied for the majority of acid soils which are kaolinitic. With Mehlich-3, Bray-1 and Resin, however, these soil test interpretations were not only applicable to kaolinitic soils, but also to clayey gibbsitic ones. Similar, but less extensive, studies were conducted for Zn. Four soils varying in clay content were evaluated in the greenhouse and one soil was studied in the field. The other variables were soil Zn concentration and soil pH. Soil testure had no effect, but inclusion of soil pH improved the soil test interepretation for Zn. It appears that the critical Mehlich-1 extractable level of Zn increases with na increase in soil PH.
Palavras-Chave: | Cultivation; Cultivo; Maize; Soybens.
Thesagro: | Adsorção; Adubação; Cerrado; Fósforo; Glycine Max; Milho; Reconhecimento do Solo; Soja; Solo; Zea Mays; Zinco.
Thesaurus Nal: | adsorption; fertilizer application; phosphorus; soil; soybeans; zinc.
Categoria do assunto: | --
Registro original: | Embrapa Cerrados (CPAC)

Exemplares:

CNPGC - (8295-1) - ADD - TS - PP - T593/87 - LIN - T593/87 - DIS
CNPS - (3996-1) - ADD - TS - -- - 87001 - LIN/87 - 1997.00365 - DIS
CPAC - (4858-1) - ADD - TS - -- - CRI3385 -  - CRI3385 - DIS
CPAC - (15928-1) - ADD - TS - -- - T023/87 - LIN - T023/87 - DIS