Data/hora: 21/09/2024 10:16:12

Biblioteca(s): 	Embrapa Solos.	
Data corrente: 	21/09/2021	
Data da última atualização: 	21/09/2021	
Autoria: 	ALLEONI, L. R. F.; PEIXOTO, R. T. dos G.; AZEVEDO, A. C. de; MELO, L. C. A.	
Afiliação: 	LUIS REYNALDO FERRACCIU ALLEONI, ESALQ/USP; RICARDO TRIPPIA DOS G PEIXOTO, CNPS; ANTONIO CARLOS DE AZEVEDO, USP; LEONIDAS CARRIJO AZEVEDO MELO, USP.	
Título: 	Components of surface charge in tropical soils with contrasting mineralogies.	
Ano de publicação: 	2009	
Fonte/Imprenta: 	Soil Science, v. 174, n. 11, p. 629-638, Nov. 2009.	
DOI: 	http://doi.org/10.1097/SS.0b013e3181c17a93	
Idioma: 	Inglês	
Conteúdo: 	Study of surface electric charges of soil colloids helps in understanding the physicochemical phenomena that influence the capacity of retaining nutrients and their availability to plants. The structural charge (sigma(0), (min)), the variable charge (sigma(q, min)), and the organic matter (OM) charge (sigma(total) (OM)) of 12 tropical soils with contrasting mineralogies were evaluated based on the difference of selectivity for Cs+ and Li+ between the functional ionizable surfaces groups and the mineral 2:1 siloxane surface. Soils were divided into three groups: G1, soils with a predominance of kaolinite and gibbsite in the clay fraction; G2, soils with hydroxy-interlayered 2:1 minerals; and G3, soils with smectite but without hydroxy-interlayered 2:1 minerals. The Cs absorption method was efficient for detecting the charge components in tropical soils. The mineral structural charge contributed 11% and 16%, 28% and 31%, and 52% and 59% of total soil charge of A and B horizons of soils from groups G 1, G2, and G3, respectively. On the other hand, OM contributed 53% and 37%, 48% and 41%, and 21% and 20% of total charge for the same samples, respectively, In highly weathered soils of group G I and, to a lesser extent, in soils in group G2, surface charges depended mainly on their variable components, resulting from the OM (sigma(toal) (OM)), as well as from imperfections found in 1:1 minerals (sigma(q, min)). The importance of OM in determining the magnitude of electric charges in humid tropical soils is highlighted.	
Thesagro: 	Matéria Orgânica; Solo.	
Thesaurus Nal: 	Soil organic matter.	
Categoria do assunto: 	P Recursos Naturais, Ciências Ambientais e da Terra	
Registro original: 	Embrapa Solos (CNPS)	
Exemplares: 	CNPS - (20765-1) - UPC - AP - DD -  -  -  - DIS